CN111356888B

CN111356888B - Temperature controlled dispensing drawer

Info

Publication number: CN111356888B
Application number: CN201880074315.7A
Authority: CN
Inventors: 赫伯特·劳森·费什尔; 伊迪丝·威尔逊; 狄恩·法布勒; 布莱恩·阿诺德; 布拉德·巴斯勒; 维哈·卡帕迪亚; 苏尼尔·贝利冈迪
Original assignee: Omnicell Inc
Current assignee: Omnicell Inc
Priority date: 2017-11-17
Filing date: 2018-11-16
Publication date: 2024-02-06
Anticipated expiration: 2038-11-16
Also published as: EP3710764A4; KR20200090808A; JP7301825B6; AU2018368950B2; BR112020008858A2; JP2021503588A; CN111356888A; AU2018368950A1; KR102592222B1; WO2019099767A1; CA3079749A1; JP7301825B2; EP3710764A1

Abstract

An apparatus for dispensing items includes a cabinet and a drawer within the cabinet. The drawer includes one or more compartments for storing items and a cooling system within the drawer. The cooling system is configured to maintain the one or more compartments in the drawer at a temperature that is less than an ambient temperature surrounding the cabinet. The drawer also includes thermal insulation on the drawer side and thermal insulation below the one or more compartments. The refrigeration system may be a thermoelectric cooling system.

Description

Temperature controlled dispensing drawer

The present application claims priority from U.S. patent application Ser. No. 15/816,775, entitled "dispensing System with temperature controlled drawer" filed on 11/17/2017, and U.S. patent application Ser. No. 16/129,579, entitled "temperature controlled dispensing drawer", filed on 9/2018. The entire disclosure of the above application is incorporated by reference for all purposes as if fully set forth herein.

Background

Many industries rely on accurate inventory and distribution of security items. For example, in a hospital setting, it is critical that the correct medication be administered to the patient at the correct dose. Furthermore, law requires protection and accurate tracking of controlled substances, and tracking of inventory of medications and supplies is also important in order to be able to implement proper business control.

Different drugs may have different storage requirements. For example, some medications or supplies may require refrigeration, while others do not. Articles requiring refrigeration may experience particular difficulties because they are typically simply stored in a refrigerator. Even though the refrigerator may have been locked, once the refrigerator is opened, all items in the refrigerator are available and can cause erroneous retrieval, transfer, or other problems.

Disclosure of Invention

According to one aspect, an apparatus for dispensing items includes a cabinet and a drawer within the cabinet. The drawer includes more than one compartment for storing items. The apparatus also includes a refrigeration system within the drawer. The refrigeration system is configured to maintain one or more compartments in the drawer at a temperature below the temperature of the cabinet's surrounding environment. The drawer also includes thermal insulation on the sides of the drawer and thermal insulation below the one or more compartments. In some embodiments, the apparatus further comprises a computer controller coupled to the drawer, the controller controlling access to the drawer. In some embodiments, the device further comprises a temperature probe within the drawer, the temperature probe providing a signal to the computer controller indicative of the temperature within the drawer, and the computer controller providing information to a user of the device regarding the temperature in the drawer. In some embodiments, the apparatus further comprises a temperature buffer surrounding the temperature probe. In some embodiments, the device further comprises one or more actuators controllable by the computer controller and coupled to the covers of respective ones of the one or more compartments, wherein the one or more actuators are disposed outside an interior of the drawer defined by thermal insulation at sides of the drawer and thermal insulation below the one or more compartments. In some embodiments, the one or more actuators comprise one or more solenoids. In some embodiments, the one or more actuators are mounted to one or more printed circuit boards that are also disposed outside the interior of the drawer defined by thermal insulation on the sides of the drawer and thermal insulation below the one or more compartments. In some embodiments, the apparatus further comprises one or more lights respectively corresponding to at least some of the one or more compartments, and the controller is configured to, upon determining to access a particular compartment: actuating one of the actuators corresponding to the particular compartment to unlock the particular compartment; and illuminating one of the lamps corresponding to the particular compartment. In some embodiments, the device further comprises an override mechanism accessible from outside the drawer, the override mechanism mechanically moving the one or more actuators to manually unlock the compartment. In some embodiments, the device further comprises an insulating plate within the cabinet, wherein the insulating plate is positioned at a top side of the drawer when the drawer is closed and within the cabinet, and wherein the insulating plate remains within the cabinet when the drawer is open. In some embodiments, the device further comprises a top insulating plate coupled to the drawer, wherein the top insulating plate is slidable relative to the drawer to expose more than one compartment. In some embodiments, the refrigeration system includes a compressor and a condenser disposed at a rear of the drawer, and an evaporator disposed between one or more compartments in the drawer and insulation below the one or more compartments. In some embodiments, the evaporator is a roll-to-roll evaporator. In some embodiments, the device further comprises a fan, wherein the fan pushes air from outside the drawer through the condenser. In some embodiments, the drawer defines an air flow path through which the fan pushes air, the air flow path being open to the environment surrounding the cabinet at the front side of the cabinet such that air enters the air flow path at the front of the cabinet and the fan causes air to be expelled from the rear of the cabinet. In some embodiments, the air flow path is at least partially defined within the thermal insulation below the one or more compartments. In some embodiments, the device further comprises one or more additional drawers, at least one of which is uncooled.

According to another aspect, a drawer includes a housing; insulation defining a climate controlled interior of the drawer; and a refrigeration system having a compressor and a condenser disposed within the drawer but outside the climate controlled interior of the drawer, and having an evaporator disposed within the climate controlled interior of the drawer. The drawer also includes a divider defining one or more compartments within the climate controlled interior of the drawer; one or more covers covering one or more compartments; an electrical interface for receiving power and control signals; and one or more actuators coupled to the one or more covers to lock and unlock the one or more compartments in response to control signals received via the electrical interface. In some embodiments, the one or more actuators are disposed outside of the climate controlled interior of the drawer. In some embodiments, the drawer further includes one or more lights corresponding to one or more compartments, the lights being responsive to control signals received via the electrical interface. In some embodiments, the drawer further comprises an air inlet at a front of the drawer; an air flow channel disposed at least partially within the insulating panel below the climate controlled interior of the drawer; and a fan sucking air to the air inlet, through the air flow passage and through the condenser, and discharging the air from the rear side of the drawer. In some embodiments, the air inlet is hidden within the handle on the front side of the drawer.

According to another aspect, a drawer includes a housing; an insulator defining an insulating interior of the drawer; an air inlet at a first side of the drawer; an air outlet on a second side of the drawer; a fan. The fan draws air into the air inlet and expels air from the air outlet and between the air inlet and the air outlet, the air flowing through an air flow path defined at least in part by the insulator. In some embodiments, the drawer further comprises a refrigeration system that cools the insulated interior of the drawer, wherein the fan flows air from outside the drawer through a condenser of the refrigeration system. In some embodiments, the first side of the drawer is a front of the drawer, and wherein the air inlet is hidden within a handle of the front side of the drawer.

According to another aspect, an apparatus for dispensing items includes a cabinet and a drawer within the cabinet. The drawer includes more than one compartment for storing items. The apparatus also includes a cooling system within the drawer. The cooling system is configured to maintain one or more compartments in the drawer at a temperature below the ambient temperature of the cabinet. The drawer also includes thermal insulation on the sides of the drawer and thermal insulation below the one or more compartments. In some embodiments, the cooling system includes a compressor, a condenser, and an evaporator. In some embodiments, the cooling system is a thermoelectric cooling system. In some embodiments, the thermoelectric cooling system further comprises a fan configured to circulate air within the drawer. In some embodiments, the thermoelectric cooling system further comprises a fan configured to both remove heat from the thermoelectric cooling unit and induce air flow under or around the thermal insulation of the drawer. In some embodiments, at least some of the compartments are defined by perforated walls that allow circulated air to pass through the walls and through the compartments. In some embodiments, the lid of at least some of the compartments in which the wall is perforated includes a descending rib that protrudes into the compartment when the lid is closed. In some embodiments, the apparatus further comprises a computer controller coupled to the drawer, the controller controlling access to the drawer. In some embodiments, the apparatus further comprises a temperature probe within the drawer, and the temperature probe provides a signal to the computer controller indicative of the temperature within the drawer. In some embodiments, the device further comprises one or more actuators controllable by the computer controller and coupled to the lids of respective ones of the one or more compartments, and the one or more actuators are disposed outside an interior of the drawer defined by thermal insulation at sides of the drawer and thermal insulation below the one or more compartments. In some embodiments, the device further comprises magnetic latches on at least some of the compartments, the magnetic latches being controlled by the computer controller to lock and unlock the covers of their respective compartments. In some embodiments, each of the magnetic latches includes a permanent magnet secured to the lid of the respective compartment, and an electromagnet secured to the wall of the compartment such that the permanent magnet contacts the electromagnet when the lid is closed, and the controller unlocks the compartment by passing an electric current through the electromagnet, causing the electromagnet to repel the permanent magnet. In some embodiments, the one or more actuators comprise one or more solenoids. In some embodiments, the apparatus further comprises one or more sensors configured to sense the position of the covers of respective compartments of the one or more compartments. In some embodiments, each of the sensors is disposed outside an interior of the drawer defined by thermal insulation at a side of the drawer and thermal insulation below the one or more compartments and coupled to its respective lid. In some embodiments, each of the sensors is coupled to its respective lid via a link through the thermal insulation of the drawer. In some embodiments, each of the sensors is coupled to its respective cover via a jacketed cable that passes through the thermal insulation of the drawer. In some embodiments, the apparatus further comprises one or more lights respectively corresponding to at least some of the one or more compartments, and the controller is configured to, upon determining to access a particular compartment: actuating one of the actuators corresponding to the particular compartment to unlock the particular compartment; and illuminating one of the lamps corresponding to the particular compartment. In some embodiments, the device further comprises an override mechanism accessible from outside the drawer, the override mechanism mechanically moving the one or more actuators to manually unlock one or more of the compartments. In some embodiments, the thermoelectric cooling system includes a closed cooling loop that contains a heat transfer fluid. In some embodiments, the heat transfer fluid is maintained under pressure such that its boiling point approaches the desired temperature of the interior of the drawer. In some embodiments, the heat transfer fluid is maintained under pressure such that its boiling point is between 2 ℃ and 8 ℃. The heat transfer fluid may be carbon dioxide. In some embodiments, the thermoelectric cooling system including the closed cooling loop and the heat transfer fluid forms a heat pipe that operates by natural convection.

According to another aspect, a drawer includes a housing; insulation defining a climate controlled interior of the drawer; and a thermoelectric cooling system disposed in a side wall of the drawer. The thermoelectric cooling system is configured to maintain the interior of the drawer at a temperature that is less than the temperature of the drawer's surrounding environment. The drawer also includes a set of walls defining one or more compartments within the climate controlled interior of the drawer; one or more covers covering one or more compartments; an electrical interface for receiving power and control signals; and one or more actuators coupled to the one or more covers to lock and unlock the one or more compartments in response to control signals received via the electrical interface. In some embodiments, the one or more actuators are disposed outside of the climate controlled interior of the drawer. In some embodiments, the drawer further includes one or more lights corresponding to one or more compartments, the lights being responsive to control signals received via the electrical interface. In some embodiments, the thermoelectric cooling system is configured to circulate cooled air in the interior of the drawer. In some embodiments, the thermoelectric cooling system includes a closed cooling loop that contains a heat transfer fluid. In some embodiments, the heat transfer fluid is carbon dioxide, which is maintained at a pressure such that its boiling point is between 2 ℃ and 8 ℃.

Drawings

Fig. 1 shows a dispensing cabinet in which the invention may be embodied.

Fig. 2 shows a portable dispensing device in which the invention may be embodied.

Fig. 3 shows a front upper oblique view of a drawer according to an embodiment of the present invention.

Fig. 4 illustrates a rear upper oblique view of the drawer of fig. 3, according to an embodiment of the present invention.

Fig. 5 illustrates an upper exploded view of the drawer of fig. 3, according to an embodiment of the present invention.

Fig. 6 illustrates a lower exploded view of the drawer of fig. 3, according to an embodiment of the present invention.

Fig. 7 shows a lower oblique view of the drawer of fig. 3 with its bottom cover removed.

Fig. 8 illustrates an upper rear oblique view of the drawer of fig. 3, according to an embodiment of the present invention.

Fig. 9 shows a partial view of the cabinet of fig. 1 with the insulating panels in place, according to an embodiment of the invention.

Fig. 10 shows another embodiment of the cabinet of fig. 1 with the insulating panels in place, according to an embodiment of the invention.

FIG. 11 illustrates an upper oblique view of the top of the drawer of FIG. 3 with many components removed to expose a computer controlled mechanism for enabling access to individual storage bins within the drawer, in accordance with an embodiment of the invention.

Fig. 12 shows a portion of fig. 11 in more detail.

Fig. 13 shows a lid of a compartment of the drawer of fig. 3 in an open position according to an embodiment of the invention.

FIG. 14 shows an upper rear oblique view of the drawer of FIG. 3 with several components removed, in accordance with an embodiment of the present invention.

Fig. 15 shows an enlarged view of a portion of fig. 14.

Fig. 16 illustrates installation of an insulation plate in the drawer of fig. 3 according to an embodiment of the present invention.

Fig. 17 shows an override mechanism according to an embodiment of the invention.

Fig. 18 shows a portion of fig. 17 in more detail.

Fig. 19 illustrates a basic thermoelectric module according to an embodiment of the present invention.

Fig. 20 illustrates a cooling unit including the thermoelectric module of fig. 19 according to an embodiment of the present invention.

FIG. 21 illustrates a drawer cooled inside the drawer using the thermoelectric cooling unit of FIG. 20 according to an embodiment of the present invention.

Fig. 22 shows an exploded view of the drawer of fig. 21.

Fig. 23 shows an exploded view of a drawer with a cooling system according to other embodiments.

Fig. 24 illustrates one manner of allowing the opening of the lid in the drawer according to an embodiment of the invention.

Fig. 25 shows the system of fig. 24 with one lid open.

Fig. 26 shows the arrangement of fig. 24 in more detail.

Fig. 27 illustrates another technique for locking and unlocking a lid of a dispensing drawer in accordance with other embodiments of the present invention.

Fig. 28 shows the system of fig. 27 with the lid in an open position.

Fig. 29 shows a refrigerated drawer according to other embodiments of the invention.

Fig. 30 shows a partial underside view of the drawer of fig. 29.

Fig. 31 shows a refrigerated drawer according to other embodiments of the invention.

Fig. 32 shows how two actuators may be mounted on the outside of an insulator in a drawer according to an embodiment of the invention.

Fig. 33 shows a compartment with a lid and a magnetic latch according to an embodiment of the invention.

Detailed Description

Fig. 1 shows a dispensing cabinet 100 according to an embodiment of the invention. The cabinet 100 includes a plurality of compartments including drawers 101a, 101b, and 107; and compartments accessible through doors 102a and 102 b. The dispensing cabinet 100 also includes a computer controller 103 and one or more data entry devices, such as a keyboard 104 and a keypad 105. The display 106 enables communication of information with a user of the dispenser cabinet 100. According to an embodiment of the present invention, the drawer 107 includes a refrigeration system as discussed in more detail below. In some embodiments, the dispensing cabinet may also include other devices.

While devices embodying the present invention may be used in a variety of applications, embodiments may be particularly useful in the medical field. For example, the dispensing cabinet 100 may contain medications or medical supplies and may facilitate accurate dispensing and tracking of medications or other medical supplies.

The computer controller 103 may include a processor, memory, input/output interfaces, and other components. The controller 103 can communicate remotely with other computer systems, such as medical record systems, inventory and accounting systems.

Various storage compartments, such as drawers 101a, 101b, and 107, may be under the control of controller 103. For example, each of drawers 101a, 101b, and 107 may include an electronically controllable locking mechanism, and may only operate under the control of controller 103. In addition, the controller 103 may store information about what supplies are stored in which compartments of the medication storage cabinet 100. In a typical basic use case, the healthcare worker may use the keyboard 104 or another input device to enter an identification of the patient under the care of the healthcare worker or who will need to be dosed during the worker's current tour. The controller 103 may access the patient's medical profile and determine what medications have been prescribed for the patient. The controller 103 may then only allow access to the drawer or drawers containing the medication prescribed for the patient. Specific compartments within the correct drawer, such as boxes, may also be highlighted, for example, with a lighted indicator, to attract the healthcare worker to the correct medication. The healthcare worker may then remove the patient's prescribed medication. The level of control performed by the controller 103 may help prevent medication and dosage errors by reducing the likelihood that a healthcare worker will remove incorrect medications from the medication dispensing cabinet 100. In addition, the controller 103 may archive and record which medications were dispensed and may forward this information to the inventory and accounting system via a wired or wireless electronic network.

Many other features and functions are possible. For example, the healthcare worker may also enter his or her identification, and the controller 103 may provide access to only those medications and supplies that the worker is authorized to access.

Although the medication dispensing cabinet 100 is shown as a fixture, the invention is not so limited. Cabinets according to other embodiments may be portable, for example, to transport medications and supplies from a central supply warehouse to a particular ward or department of an institution. It will be appreciated that the particular arrangement of drawers, doors or other features of a cabinet according to embodiments of the invention may vary. For example, some cabinets or dispensing carts embodying the present invention may use only drawers. Many different sizes and styles of compartments may be used, depending on the size of the material to be dispensed and its desired level of safety.

A cabinet embodying the invention may include guides or mounting features that are spaced apart at standard distances, and different drawers may span different multiples of the spacing distance. Drawers that span only a single separation distance may be referred to as "single" height drawers. Drawers that span two spaced distances may be referred to as "dual" height drawers. Three-level and higher drawers are also possible. A cabinet, such as cabinet 100, may be configured with a combination of drawer heights, depending on the size of the items to be stored. In the example of fig. 1, drawer 101b is a single-height drawer, while drawer 107 is a three-height drawer.

Fig. 2 illustrates a portable dispensing device 200 in which the present invention may be embodied. Preferably, the portable dispensing device 200 may perform functions similar to those described above with respect to the dispensing cabinet 100. The dispensing device 200 includes wheels 201 to enable a healthcare worker to push the device from one room to another. The dispensing device 200 may include more than one battery to power a computer controller that performs similar tasks as the controller 103 discussed above, and to power other functions of the dispensing device 200. In addition, the dispensing device 200 may preferably be connected to a mains power supply at a convenient time to charge and power the battery without using the battery when the device is in a particular position for a period of time. Various input/output devices 202 may be provided and may be particularly adapted to be portable, for example, in order to minimize power consumption. The dispensing device 200 also includes a plurality of drawers 203 having different heights. Each drawer 203 may include a visual indicator 204 for guiding a user to a particular drawer 203, as explained in more detail below. More than one of drawers 203 may include a refrigeration system according to embodiments of the invention. Other drawers within the cabinet 100 may not be refrigerated.

Other types of dispensing units that may embody the present invention or include features that may be used with embodiments of the present invention are described in the following commonly owned U.S. patents and patent applications, the contents of which are incorporated herein by reference: U.S. Pat. No. 6,272,394 to Lipps at 7 of 2001, U.S. Pat. No. 6,385,505 to Lipps at 5 of 2002, U.S. Pat. No. 6,760,643 to Lipps at 6 of 2004, U.S. Pat. No. 5,805,455 to Lipps at 9 of 1998, U.S. Pat. No. 6,609,047 to Lipps at 19 of 2003, U.S. Pat. No. 5,805,456 to Higham et al at 9 of 1998, U.S. Pat. No. 5,745,366,1999 to Higham et al at 5 of 28 of 1998, U.S. Pat. No. 5,905,653 to Higham et al at 18 of 1999, U.S. Pat. No. 5,927,540 to Godlewski at 7 of 1999, U.S. Pat. No. 6,039,467 to Holmes at 21 of 2000, U.S. Pat. No. 6,640,159 to Holmes et al at 10 of 2003, U.S. Pat. No. 6,760,643 to Ard et al at 11 of 2000, U.S. patent No. 5,377,864 issued 1/3/1995 to Blechl et al, U.S. patent No. 5,190,185 issued 3/2/1993 to Blechl, U.S. patent No. 6,975,922 issued 12/13/2005 to Duncan et al, U.S. patent No. 7,571,024 issued 8/4/2009 to Duncan et al, U.S. patent No. 7,835,819 issued 11/16/2010 to Duncan et al, U.S. patent No. 6,011,999 issued 1/4/2000 to Holmes, U.S. patent No. 7,348,884 issued 3/25/2008 to Higham, U.S. patent No. 6,170,929/9/2010/3/9 to Higham, U.S. patent No. 6,170,929/2012/2/28 to Wilson et al, U.S. patent No. 8,126,590 issued to Vahlberg et al, U.S. patent No. 8,280,550/2012/10/2/8/2012/published by Levy et al.

Fig. 3 shows a front upper oblique view of the drawer 107 in more detail, according to an embodiment of the invention. As viewed from the front side 301, the drawer 107 has a front side 301, a rear side 302, and right and left sides 303 and 304. The front side 301 is the side that is displayed on the front of the cabinet once the drawer 107 is installed in the cabinet and is the side from which the user accesses the drawer 107. The drawer 107 may include guides 305 for mounting the drawer 107 into a cabinet such as the cabinet 100 and enabling the drawer to slide open (in the direction of the front side 301) and closed (with the drawer 107 substantially entirely within the cabinet). One or more panel plates 306 provide a decorative appearance to the front of the drawer 107, may provide an undercut handle to a user to grasp in opening the drawer 107, and may include other features as described in more detail below.

The front 307 of the drawer 107 includes a plurality of compartments, which in fig. 3 are covered by a lid 308. The rear 309 houses various components of the refrigeration system, as will be described in more detail below.

Fig. 4 shows a rear upper oblique view of the drawer 107. A mechanical latch 401 may be provided that may interact with the cabinet 100. For example, the controller 103 may control the latch such that the drawer 107 may be opened only when the worker requesting access to the drawer 107 has provided the appropriate credentials. The cover 308 similarly may be controllable such that only the storage location containing the desired medication or product is operable by the worker.

Various electrical connectors 402 may be provided, and a cable (not shown) may be attached to the electrical connectors 402 such that the drawer 107 may receive power from the cabinet 100 and may communicate with the controller 103.

Fig. 5 and 6 show upper and lower partial exploded views of the drawer 107 according to an embodiment of the present invention. The interior of the drawer 107 is substantially surrounded by insulation comprising a side insulation plate 501, a rear insulation plate 502, a front insulation plate 503 and a bottom insulation plate 504. Insulation plates 501-504 may be made of any suitable insulating material, such as a moldable foam insulation, such as polyisocyanurate, polystyrene, polyurethane, or another insulation. Although four different insulating plates are shown, the insulating members may be formed of more or fewer different segments. For example, the front insulating plate 503 may be integrally molded with the bottom insulating plate 504. Other combinations are also possible. (insulation at the top of the drawer 107 will be discussed below).

The compartment 505 is located in a room formed by the insulating plates 501 to 504. The compartment 505 may be defined by a divider made of any suitable material and formed by any suitable process, but may also be conveniently molded from a polymer, such as polycarbonate, ABS, another polymer, or a blend of polymers. In other embodiments, the compartment 505 may be made of a metal, such as stainless steel, aluminum, or another suitable metal. The compartments 505 may be integrally formed from a single piece of material, or may be separate from each other and placed in the drawer 107 in any feasible combination. The compartment 505 is covered by a cover 308.

An evaporator 506 is disposed between the compartment 505 and the bottom insulating plate 504. The evaporator 506 is part of a refrigeration system integrated into the drawer 107. The evaporator 506 may be, for example, a roll-to-roll evaporator formed by roll bonding two sheets of metal with a pattern of channels marked thereon, and then inflating the channels to form a network or serpentine path through the channels to flow the refrigerant. The evaporator 506 absorbs thermal energy from the interior of the drawer 107 by virtue of its low temperature and brings it out of the interior of the drawer 107, thereby cooling the interior of the drawer 107, including the compartment 505.

Other components of the refrigeration system include a compressor 507 and a condenser 508, as well as an expansion valve (not shown). These components form an assembly that implements a conventional refrigeration cycle. The refrigeration system preferably uses a refrigerant that does not contain a chlorofluorocarbon (CFC).

After the refrigerant has been heated in the evaporator 506 and compressed in the compressor 507, a fan 509 draws air through the condenser 508 to cool the refrigerant to discharge thermal energy to the exterior of the cabinet 100.

A glycol bottle 510 may be provided and the glycol bottle 510 with its own lid 512 may be fitted in a special compartment 511 in the interior of the drawer 107. Preferably, the temperature sensor is immersed in the glycol within the bottle 510 and is connected to the controller 103 such that the controller 103 is able to monitor the temperature inside the drawer 107. The glycol serves to buffer the sensor from rapid fluctuations in apparent temperature that may be caused, for example, by opening the drawer 107 from the cabinet 100. In some embodiments, the controller 103 may signal the refrigeration system to turn on and off the cycle based on the temperature as sensed by the temperature sensor.

Fig. 7 shows a lower oblique view of the drawer 107 with its bottom cover removed, thereby exposing the bottom insulating plate 504. In this example embodiment, the bottom insulating plate 504 has a funnel-shaped air flow path 701 molded into it. When the drawer 107 is fully assembled, a bottom panel (not shown) forms the remaining side of the air flow path 701. Air may enter the air flow path 701 through an opening in the front side of the drawer 107, such as an opening hidden in one of the panel plates 306. The funnel shape of the air flow path 701 directs air to the condenser 508 under the urging of a fan 509 (not visible in fig. 7). After flowing through the condenser 508, the air is discharged to the environment at the rear of the cabinet 100.

This air flow arrangement serves multiple purposes. First, as part of a refrigeration cycle, it provides cooling air to the condenser 508 to cool the refrigerant in the refrigeration system. Air is exhausted from the rear of the cabinet 100 instead of the front, which may be preferable for user comfort. And second, the air flow under the insulating plate 504 may evaporate and drain any condensate that may form under the insulating plate 504. The standoffs 702 may hold the rear cover away from the insulator plate 504, allowing at least a small amount of air 703 to flow over substantially the entire underside of the insulator plate 504.

Fig. 8 shows an upper rear oblique view of the drawer 107 according to an embodiment of the invention. The view of fig. 8 is similar to the view of fig. 4 with the addition of a top insulating plate 801. The top insulating plate 801 may be shaped and sized to slide into an open recess left in the top of the drawer 107 by other components. For example, the top insulating plate 801 may be fitted between the tops of the side insulating plates 501 and contact the front insulating plate 503 when the top insulating plate 801 is completely mounted on the drawer 107. The top insulating plate 801 may also contact the rear insulating plate 502 (not visible in fig. 8) such that the interior of the drawer 107 is substantially enclosed in insulation. The top insulating plate 108 is preferably mounted in the cabinet 100 such that when the drawer 107 is open, the top insulating plate 801 remains inside the cabinet 100 so as not to interfere with access to the compartments in the drawer 107. When the drawer 107 is closed, the top insulating plate 801 automatically covers the drawer 107 again.

In other embodiments, the top insulating plate 801 may travel with the drawer 107 when the drawer 107 is open, and the user may simply slide the top insulating plate 801 back toward the cabinet 100 to gain access to the interior of the drawer 107.

Top insulating plate 801 may be made of any suitable material, such as a material similar to the other insulating plate materials or a different material.

Fig. 9 shows a partial view of the cabinet 100 with the insulating plate 801 in place over the drawer 107. The drawer immediately above the drawer 107 has been removed. When the drawer 107 is opened and closed, the insulating plate 801 remains in place so that the interior of the drawer 107 is accessible when the drawer 107 is opened, but when the drawer 107 is closed, the drawer 107 is completely insulated. In the example of fig. 9, brackets 901 hold insulating plate 801 in place within cabinet 100 and drawer 108 slides under insulating plate 801. However, other arrangements are also possible.

For example, fig. 10 shows another embodiment in which an insulating plate 801 is slidingly captured within a recess 1001 in the side of the drawer 107. The insulating plate 801 may be attached to the rear wall of the cabinet 100 such that the insulating plate 801 does not slide out of the cabinet 100 when the drawer 107 is opened. In other embodiments, when the drawer 107 is open, the user may simply push back the insulating plate 801 to expose the interior of the drawer 107.

Because the interior of the drawer 107 is at a cold temperature, it may be desirable to keep the electronic and electromechanical components out of the interior of the drawer 107 to the extent possible to avoid potential cold-induced problems. For example, FIG. 11 shows an upper oblique view of the top of the drawer 107 with many components removed to expose a computer controlled mechanism for enabling access to individual storage bins within the drawer 107. Fig. 12 shows a portion of fig. 11 in more detail. In this example, the lid 1101 includes a lever 1102 configured to rotate with the lid 1101 about an axis 1103. In the position shown, the blade 1104 connected to the armature of the solenoid 1105 prevents the lever 1102 and thus the cover 1101 from rotating. In this condition, the bin under the lid 1101 is locked.

However, when solenoid 1105 is energized, for example under the control of controller 103, blade 1104 is withdrawn, allowing lever 1102 and cover 1101 to rotate to an open position. Fig. 13 shows the lid 1101 in an open position. For example, once the solenoid 1105 has released the lid, the user may use a finger pull 1301 to lift the lid 1101. Once the user has completed accessing the bin under the lid 1101, the user may simply push the lid 1101 back to the closed position. The lever 1102 interacts with the angled top of the vane 1104 to deflect the vane 1104 downward to allow the lever 1102 to pass. Once the lever 1102 has passed the vane 1104, the vane 1104 may return to its normal upward position under the influence of a spring (not visible in fig. 13) to lock the lid 1101 in the closed position.

Solenoid 1105 is but one example of one type of actuator that may be used to control intermittent access to drawer 107, and other types of actuators may be used, such as magnetic actuators, motors with suitable linkages, or other types of actuators.

The architecture of the drawer 107 may at least partially protect the solenoid 1105 and its drive electronics from the cold environment within the drawer 107. Fig. 14 shows an upper rear oblique view of the drawer 107 with several components removed, and fig. 15 shows an enlarged view of a portion of fig. 14. The printed circuit board 1401 is mounted to a side 1402 of the drawer 107. A plurality of solenoids 1105 are mounted to a circuit board 1401 and connected to other circuits (not shown) via a connector 1501, and ultimately to the controller 103. Similar components may also be attached to the inner face of the other side 1403 of the drawer 107, but are not visible in fig. 14.

A plurality of sensors 1502 may be provided to provide positive feedback when the lever 1102 of one of the covers 308 is in the closed position. A Light Emitting Diode (LED) 1503 may be present and may also be controlled by the controller 103 to visually indicate the status of a particular compartment through a light pipe 1504 extending to the top of the drawer 107.

With the printed circuit board 1401 including the solenoid 1105 in place, the insulation of the drawer 107 may be placed in place, as shown in fig. 16. For example, side insulating plate 501 includes a plurality of recesses 1601 for receiving printed circuit board 1401 and components thereon, including solenoid 1105. Once the side insulating panels 501 are in place in the drawer 107, the printed circuit board 1401 and its associated components are positioned outside the refrigerated interior of the drawer 107. The various slots 1602 in the insulating plate 501 provide access to components on the circuit board 101 and are as small as possible so as not to unnecessarily compromise the insulating effect of the insulating plate 501.

In some embodiments, a manual override mechanism is provided for manually unlocking the compartments in the drawer 107 without reliance on the controller 103. This capability may be useful, for example, during a power outage or other situation when the controller 103 is unable to open a compartment. Fig. 17 and 18 illustrate an example override mechanism. The override board 1701 is fitted under an insulator (not shown) at the bottom of the drawer 107, and includes a riser 1702 corresponding to the solenoid 1105 at the side of the drawer 107. The risers 1702 can extend within the temperature controlled interior of the drawer 107 so as to pass through slots in the lower insulator plate. The override pad 1701 is accessible from the bottom of the drawer 107. For example, a user may insert a finger through an aperture 1703 in the floor 1704 of the drawer 107 to actuate the override plate 1701 against the spring 1705.

As best seen in fig. 18, when the override paddle 1701 is actuated, the ramp feature 1801 in each riser 1702 interacts with the pin 1802 on the armature 1803 of the corresponding solenoid 1105, pulling the armature 1803 and blade 1104 downward. With the blade 1104 extracted, the corresponding cover is unlocked, as described above and shown in fig. 13.

In another embodiment, the distribution device uses a thermoelectric refrigeration system, rather than the refrigeration system having a compressor and condenser as described above.

Fig. 19 shows a basic thermoelectric module 1900. The plurality of pillars 1901 are made of alternating N-type and P-type semiconductors. The pillars 1901 are electrically connected in series between the electrodes 1902, and in thermal parallel between the hot side plate 1903 and the cold side plate 1904. When a DC voltage is applied across the electrode 1902, heat is transferred from the cold side plate 1904 to the hot side plate 1903, thereby cooling the cold side plate 1904 and heating the hot side plate 1903. The plates 1903 and 1904 are made of a thermally conductive material. The module 1900 may be used to cool or heat a space alone or in combination with other similar modules. Thermoelectric cooling has the advantage of not requiring moving parts. For a module per square inch, a thermoelectric module, such as module 1900, can transfer up to about 15 to 30 watts or more of heat, measured at zero temperature differential.

Fig. 20 shows a cooling unit 2000 according to an embodiment of the present invention for cooling a space 2001 on one side of a panel 2002. A plurality of thermoelectric modules 1900 are sandwiched in thermal contact between a fin cold side heat sink 2003 and a fin hot side heat sink 2004. Thermoelectric module 1900 is positioned and energized to transfer heat from cold side heat sink 2003 to hot side heat sink 2004 to cool cold side heat sink 2003. The cold side fan 2005 is arranged to force air from the cooling space 2001 into the fins of the cold side radiator 2003. The air is cooled by its contact with the cold side heat sink 2003 (the cold side heat sink 2003 is in turn cooled by the thermoelectric module 1900), and is discharged back into the cooling space 2001 by the fins of the cold side heat sink 2003. Thus, the air in the cooling space 2001 is further cooled.

The hot side fan 2006 is arranged to draw air from the fins of the hot side radiator 2004. The air is heated by contact with the hot side heat sink 2004 and is discharged into the space on the hot side of the system through the fins of the hot side heat sink 2004.

It will be appreciated that the direction of air flow through one or both of fans 2005 and 2006 may be reversed from the orientation shown in fig. 20.

Fig. 21 illustrates a drawer 2100 for cooling the inside of the drawer using a thermoelectric cooling unit 2000 according to an embodiment of the present invention. Drawer 2100 is similar to drawer 107 described above in many ways, with drawer 2100 being configured to be inserted into a dispensing cabinet, such as dispensing cabinet 100. Drawer 2100 has a plurality of compartments for storing items and the compartments are covered by individually lockable lids 2101. Any suitable number of compartments may be provided, depending on the size of the drawer 2100 and the size of the items to be stored in the drawer 2100. The compartments may be of different sizes or may all be of the same size.

Fig. 22 shows an exploded view of the drawer 2100. The interior of drawer 2100 is preferably lined with insulation 2201 to reduce the amount of energy required to cool the interior space. Thermoelectric cooling unit 2000 is mounted in any convenient wall of drawer 2100, in this example rear wall 2202. The thermoelectric cooling unit 2000 draws power from the electronics (not shown) of the drawer 2100 and ultimately from the cabinet 100. The thermoelectric cooling unit 2000 is positioned to transfer heat from the interior of the drawer 2100 to a space external to the drawer 2100. The fan of the thermoelectric cooling unit 2000 serves to circulate air inside the drawer 2100 to cool the inside of the drawer 2100, and to provide an air flow to the external heat sink of the thermoelectric cooling unit 2000 to discharge heat to the outside of the drawer 2100.

In some embodiments, fans of the cooling unit 2000 external to the drawer 2100 may be positioned, directed, or otherwise arranged to also provide air flow under or around the insulating space of the drawer 2100. For example, in addition to providing air flow above the heat sink of thermoelectric cooling unit 2000, a fan may provide air flow below the insulating space of drawer 2100 similar to the air flow shown in fig. 7 to help prevent condensation from occurring at the bottom of drawer 2100. Fig. 29 and 30 illustrate an embodiment in which the cooling unit 2000 is enclosed in a protective cover 2901, which protective cover 2901 is connected at its bottom end 2902 to a plenum 3001 below the insulation 2201. An external fan of the cooling unit 2000 generates an air flow 2903 outside the protective cover 2901. Fig. 30 illustrates an underside view of the drawer 2100 with its bottom cover removed. As can be seen in fig. 29 and 30, the air flow 2903 passes under the insulation 2201 before being directed up to the protective cover 2901 and out to the surrounding environment.

Any other suitable arrangement may be used to create an air flow under or around the insulating space of the drawer 2100. For example, in other embodiments, two separate fans may be provided-one for creating an air flow under or around the insulating space and one for exhausting heat from the cooling unit 2000.

Referring again to fig. 22, compartment 2203 is individually enclosed. In the example drawer 2100, the compartments 2203 are molded into the unit 2204, but any suitable manner of defining the respective compartment spaces may be used. The walls of the compartment 2203 may be perforated by openings, such as opening 2205, so that air may circulate within the drawer 2100, passing through the walls and the compartment. The underside of the cover 2101 may include a descending rib 2206, the descending rib 2206 protruding into the compartment when the cover 2101 is closed. The ribs 2206 thus prevent the compartment 2203 from being completely filled. The top of the compartment remains substantially open, allowing air flow throughout the drawer 2100.

As in other embodiments, a temperature sensor within the drawer 2100 preferably provides a signal to a controller, such as the controller 103, indicative of the temperature within the drawer 2100. The temperature sensor may be immersed in a glycol bottle or other buffer, if desired. The controller 103 may circulate electrical power to the thermoelectric cooling unit 2000 as needed to maintain a substantially constant temperature within the drawer 2100.

Although the drawer embodying the invention may be used for any purpose, it may be particularly suitable for storing vaccines. The federal guidelines in the united states state specify that vaccines should be stored at temperatures of 2 ℃ to 8 ℃.

The arrangement of fig. 21 and 22 may have several beneficial aspects. For example, thermoelectric cooling systems are easy to install and operate, have no moving parts other than fans, and do not contain any liquids that may leak and cause damage in the event of a failure. In addition, thermoelectric cooling unit 2000 may be smaller than the compressor-based systems described above, and thus thermoelectric cooled drawers may have a greater storage capacity than an equally sized drawer cooled using a compressor-based system.

Fig. 23 shows an exploded view of a drawer 2300 with a cooling system according to other embodiments. The drawer 2300 includes a thermoelectric cooling unit 2301 similar to the thermoelectric cooling unit 2000, but may not have a fan inside the drawer 2300. Rather than cooling the interior of the drawer with circulated cooling air, the drawer 2300 includes a cooling circuit 2302 filled with a heat transfer fluid. For example, the cooling circuit 2302 may be a closed circuit of copper or other piping filled with carbon dioxide (CO) at a pressure ₂ ) So that CO ₂ About at or slightly below a desired temperature inside the drawer 2300. In some embodiments, the CO within cooling circuit 2302 ₂ May be at a pressure of about 40bar (about 40 atmospheres) such that the CO ₂ The boiling point of (2) is about 5 ℃. The cooling circuit 2302 may thus form a passive heat pipe cooler.

When CO ₂ Upon cooling in thermoelectric cooling unit 2301 (via an appropriate heat exchanger), CO ₂ Condensate by gravity and descend to a circuit disposed in the floor of the drawer 2300. When CO ₂ As it circulates through the drawer 2300, it absorbs heat from the interior of the drawer 2300 and boils, thereby cooling the interior of the drawer 2300. Gaseous CO ₂ And rises again toward thermoelectric cooling unit 2301 where it cools again, continuing the cycle. As in other embodiments, a temperature sensor within the drawer 2300 may provide a signal indicative of the temperature within the drawer 2300 such that the controller may cycle the thermoelectric cooling unit 2301 on and off to maintain a desired temperature.

Although somewhat more complex than the air cooling system of drawer 2100 described above, the system of drawer 2300 may have certain advantages. For example, because it does not rely on air circulation throughout the drawer 2300, the compartment 2303 may not need perforations and may be filled to a higher level, resulting in less dead space and higher capacity for the drawer 2300. Thus, the lid 2304 may not require ribs on its bottom side to prevent complete filling of the compartment 2303.

Although it is possible to useOther cooling fluids, but CO ₂ Or the like may have the following advantages: any leakage in the system will only result in the release of harmless gases into the atmosphere and thus will not result in damage to the electronics of the storage cabinet or the materials stored in the drawer 2300. Furthermore, placement of the cooling circuit 2302 in the bottom of the drawer 2300 is merely one example of a suitable circuit placement. In other embodiments, the cooling circuit 2302 may include lines passing between the compartments 2303 along the sides of the drawer 2300 or in another location or combination of locations. In some embodiments, the cooling circuit 2302 may be formed as a roll-bond unit similar to the evaporator 506 described above.

Regardless of how the drawer according to embodiments of the invention is cooled, during design of the drawer, care may be taken that condensate may be present within the drawer or at cold surfaces near the drawer. Condensate may tend to form on cold surfaces exposed to air and may be detrimental to electronics, electromechanical actuators, or other electrical or mechanical components. Preferably, the insulation surrounding the interior of the drawer is substantially insulating, with its outer surface maintained above the dew point of the surrounding atmosphere. In that case, any circuit board, electromechanical actuator or other electrical or mechanical component outside the cooling space will remain substantially safe from condensation as long as cold air leakage and other insulation gaps are minimized.

However, a cover, such as cover 2101 or 2304, must operate in the cooling space and must be automatically actuated. In an embodiment of the invention, measures are taken to position any electromechanical actuator outside the cooling space, and to couple the actuator to a cover within the cooling space, preferably in a manner that minimizes cold leakage.

Fig. 24 illustrates one manner of allowing the opening of the lid in the drawer according to an embodiment of the invention. Some support structures, wiring, etc. have been omitted from the figures for clarity. In this example, an actuator, such as a solenoid 2401, may be positioned outside of a cooling space 2402 defined by an insulator 2403. Each solenoid 2401 has a plunger 2404 that is electrically actuated in response to a signal from a controller and is associated with a linear potentiometer 2405. In the "locked" position, plunger 2404 protrudes from solenoid 2401 and prevents movement of slider 2406 of linear potentiometer 2405. A link 2407 connects the slider 2406 to a rod 2408 on the cover 2409. In the case where the slider 2406 is prevented from moving, the cover 2409 cannot be opened.

Fig. 25 shows the system of fig. 24 with the cover 2409 open. The plunger 2404 of the solenoid 2401 has been retracted by the solenoid 2401, releasing the slider 2406 so that it can be moved by the link 2407 when the user lifts the cover 2409. A signal from the linear potentiometer 2405 may be sent to a controller that indicates that the cover 2409 is open.

Each cover may be equipped with a similar solenoid-potentiometer-linkage arrangement. In this arrangement, the solenoid 2401 and potentiometer 2405 remain outside of the cooling space 2402 and are therefore substantially protected from possible condensation. Only the link 2407 penetrates the insulator 2403 such that any opening in the insulator 2403 is small and may not significantly affect the insulating effectiveness of the insulator 2403.

Linear potentiometer 2405 may have the advantage of indicating the precise state of its associated cover, such as the degree to which the cover is open. In other embodiments, a simple photointerrupter or other simple binary indicator that indicates whether the cover is open or closed may be used.

Fig. 26 shows the solenoid arrangement of fig. 24 in more detail. The ramp 2601 on each plunger 2404 allows the slider 2406 to push the plunger 2404 back into the solenoid 2401 when the corresponding lid is closed, thereby latching the lid closed. In addition, a manual release lever 2602 may be provided on each solenoid to enable a user to override the locking mechanism of the lid and manually open the lid in the event of a power outage or other malfunction. Preferably, the manual release lever 2602 is accessible from outside the drawer.

Fig. 27 illustrates another technique for locking and unlocking a lid of a dispensing drawer in accordance with other embodiments of the present invention. The system of fig. 27 uses sheath cable 2701 to connect cover 2409 to other components of the system, rather than using mechanical linkages having rigid components. Sheath cable 2701 includes sheath 2702, which may be penetrated and secured to insulator 2403. Sheath cable 2701 also includes a movable inner wire or cable 2703 that is axially movable within sheath 2702. The sheath cable 2701 may be of the type commonly used for bicycle transmissions and brake cables. In fig. 27, the cover 2409 is in a closed position. A stop 2704 on the cable 2703 is held behind the plunger 2404 of the solenoid 2401 so that the cover 2409 is prevented from being opened. The end of the cable 2703 is wound around a capstan 2705, the capstan 2705 being in turn connected to a constant force spring 2706 and a rotary encoder 2707. The constant force spring 2706 maintains tension on the cable 2703, thereby holding the cover 2409 in its closed position.

Upon receiving a command to unlock the cover 2409, the solenoid 2401 is energized to retract the plunger 2404. The user may then lift the cover 2409 against the tension of the constant force spring 2706 and retrieve the desired item from the compartment below the cover 2409. The encoder 2707 may send a signal to the controller indicating the position of the winch 2705 and thus the position of the cover 2409. In other embodiments, a simple photointerrupter or other binary sensor may be used. An encoder, such as encoder 207, may have the following advantages: for example, when the drawer is returned to the interior of the cabinet, encoder readings for the closed position of the lid may be recorded after each use. This accommodates drift in cable length or other effects, for example, in firmware.

Fig. 28 shows the system of fig. 27 with the cover 2409 in an open position. Plunger 2404 of solenoid 2401 has been retracted allowing stop 2704 to pass through plunger 2404 when cover 2409 is opened. Some of the cable 2703 has been unwound from the winch 2705. When the user closes the cover 2409, the spring 2706 assists in retracting the cable 2703. The stop 2704 may rest behind the plunger 2404, preventing the cover 2409 from opening until the solenoid 2401 is again actuated. Preferably, each cover 2409 has a mechanical detent that will retain the cover in its open position, although the spring 2706 will cause any tension in the cable 2703.

Although only one solenoid 2401 and sheath cable 2701 are shown in fig. 27 and 28, it will be appreciated that a similar arrangement may be provided for any lockable lid of a dispensing drawer. In addition, support structures, fasteners, and other items have been omitted from fig. 27 and 28 for clarity of illustration.

The systems of fig. 27 and 28 using a jacketed cable, such as jacketed cable 2701, may have the following advantages: sheath 2702 need not move relative to insulator 2403 and thus can be tightly sealed to insulator 2403. Additionally, the flexibility of sheath cable 2701 may provide design freedom in the positioning of other components, such as solenoid 2401 or other actuators.

Fig. 31 shows an exploded view of a refrigerated drawer 3100 according to other embodiments of the invention. In some of the above embodiments, for example, as shown in fig. 14 and 15, a separate actuator is placed alongside each compartment in the drawer. As can be seen in fig. 22, this may result in the compartments being spaced apart from each other in the front-rear direction of the drawer with unused space therebetween. The use of a remote actuator of the type shown in fig. 24 or 27 may bring the compartments closer together than in some other embodiments, resulting in more storage space being available in the drawer 3100.

In the example embodiment of fig. 31, the bin is formed from a tray 3101 with a simple thin divider 3102. The divider 3102 may slide into a groove or recess 3106 in the tray 3101, or may be positioned in some other manner. The divider 3102 may be permanently secured to the tray 3101, for example, by solvent bonding or permanent snap fit, or may be removable. In other embodiments, the tray 3101 may be formed with integrated dividers, for example, by injection molding.

The tray 3101 and dividers 3102 are preferably perforated by openings, such as openings 3103, so that air can circulate within the drawers 3100, through the walls and compartments in the tray 3101. The lid 3104 of the drawer 3100 can include a descending rib 3105 that protrudes into the compartment 2206 when the lid 3104 is closed. The ribs 3105 thus prevent the compartment from being completely filled. The top of the compartment remains substantially open, allowing air flow throughout the drawer 3100.

The covers 3104 may be positioned closer together in the front-to-back direction of the drawer 3100 than in some other embodiments. The thinness of the divider 3102 allows for larger compartments to be created within the tray 3101 than in other embodiments, thereby increasing the storage capacity of the drawer 3100.

Fig. 32 shows how two actuators may be mounted on the exterior of the insulator 3201 of the drawer 3100 to actuate two of the lids 3104.

In other embodiments, the magnetic latch system may be used to refrigerate a lid in a drawer. Fig. 33 shows a compartment 3301 with a lid 3302. An electromagnet 3303 is mounted on one corner of the compartment 3301, and a permanent magnet 3304 is mounted in the cover 3302. When the lid 3302 is closed, the permanent magnet 3304 is positioned above and preferably in contact with the electromagnet 3303. In the absence of current through electromagnet 3303, cover 3302 remains closed by magnetic attraction between permanent magnet 3304 and electromagnet 3303. The permanent magnet 3304 is preferably strong enough so that the cover 3302 may be considered locked. For example, the permanent magnet 3304 may be attracted to the electromagnet 3303 with a force of up to five pounds or more, making it difficult to open the lid 3302 without tools.

To unlock the lid 3302, a controller, such as the controller 103, causes current to flow through the electromagnet 3303 in one direction to generate a repulsive force against the permanent magnet 3304. With sufficient current, attraction of the permanent magnet 3304 to the electromagnet 3303 can be overcome, and the lid 3302 can be easily lifted. In some embodiments, the current level may be selected to be slightly less than the current required to fully overcome the attractive force, such that the lid 3302 may be opened with only a small amount of lifting force. In other embodiments, the current is high enough to completely overcome the attraction between the two magnets, and the lid 3302 may open due to the repulsive force of the electromagnet 3303.

In some embodiments, the positions of the electromagnet 3303 and the permanent magnet 3304 may be reversed. In other embodiments, permanent magnets may not be required. Conversely, the permanent magnet 3304 may be replaced by a simple plate made of ferromagnetic material, and the cover 3302 may be locked by passing an electric current through the electromagnet 3303. To unlock the lid 3302 in this arrangement, the current flow is simply stopped. However, while this alternative arrangement is possible, it has the following disadvantages: except that current is always drawn when the lid is unlocked. In addition, the cover may be unlocked during a power failure. In the preferred embodiment of fig. 33, which includes permanent magnet 3304, the cover is locked by default and does not draw current in its locked state.

As mentioned above, it is possible to use a tool to force the lid 3302 open from its locked state. Preferably, detection circuitry is provided to detect such intrusion. For example, a hall effect sensor may be positioned near the electromagnet 3303 to detect the magnetic field of the permanent magnet 3304 when the lid 3302 is closed. If the sensor detects that the magnetic field has disappeared (or sufficiently weakened) without the electromagnet 3303 energized, it may be assumed that the cover 3302 has been pried open and an alarm or warning may be raised. For example, an audible alarm may be raised at the cabinet location, or an electronic message may be forwarded via the controller 103 to the appropriate contacts for investigation.

In other embodiments, the electromagnet 3303 may be loosely mounted to the compartment 3301 such that the lid 3302 may be lifted slightly while the compartment 3301 remains locked. The allowed travel is preferably sufficient to be detected by any inspection circuit, but insufficient to allow access to the locked compartment. This capability may be used during the "restocking" mode. A user authorized to do so, for example, a pharmacist tasked with restocking a compartment, may place the cabinet in a restocking mode. In this mode, a slight lifting of one of the lids signals the controller via the sensor that the technician wishes to open that particular compartment for restocking. The controller then unlocks the compartment. This capability allows the restocking technician to quickly open the compartment as needed without entering information into the controller. Once restocking is complete, the technician preferably terminates the restocking mode so that the compartments remain locked until the user correctly requests dispensing of the items.

The arrangement of fig. 33 positions at least some of the electrical or electronic components within the refrigerated space. For example, the electromagnet 3303 is within a refrigerated drawer and may be mounted to a printed circuit board below the compartment 3301. The plate may also house any closure sensors, lights or other elements. Preferably, any printed circuit board and associated electronic components are encapsulated with a water-resistant conformal coating to avoid degradation or damage due to moisture condensation.

It is to be understood that all possible combinations of features disclosed herein are also to be considered as disclosed.

The present invention has now been described in detail for purposes of clarity and understanding. It will be understood, however, that certain changes and modifications may be practiced within the scope of the appended claims.

Claims

1. An apparatus for dispensing items, comprising:

a cabinet;

a drawer within the cabinet, the drawer comprising one or more compartments for storing items, wherein the drawer comprises a housing and a thermal insulation inside the housing;

a thermal insulator at a side of the drawer and a thermal insulator below the one or more compartments, the thermal insulator and the housing of the drawer together defining a plenum;

A refrigeration system within the drawer, the refrigeration system comprising a thermoelectric cooling unit (TEC) enclosed in a protective enclosure, the protective enclosure having a top and a bottom, the bottom of the protective enclosure being connected to the plenum, the refrigeration system configured to maintain the one or more compartments in the drawer at a temperature less than a temperature of an ambient environment of the cabinet; and

a fan, wherein the fan pushes air from outside the drawer through the refrigeration system,

wherein the drawer defines an air flow path through the plenum and the protective cover, and the fan pushes air through the air flow path, the plenum being open to the environment surrounding the cabinet on the front side of the cabinet such that air enters the air flow path at the front of the drawer and into the plenum, and the fan vents the air from the protective cover at the rear of the drawer, and wherein the air flow path is defined at least in part between the thermal insulation and the housing and below the one or more compartments.

2. The device of claim 1, further comprising a computer controller coupled to the drawer, the controller controlling access to the drawer.

3. The device of claim 2, further comprising a temperature probe within the drawer, wherein the temperature probe provides a signal to the computer controller indicative of the temperature within the drawer, and wherein the computer controller provides information to a user of the device regarding the temperature in the drawer.

4. The apparatus of claim 3, further comprising a temperature buffer surrounding the temperature probe.

5. The device of claim 2, further comprising one or more actuators controllable by the computer controller and coupled to lids of respective ones of the one or more compartments, wherein the one or more actuators are disposed outside an interior of the drawer defined by the thermal insulation at the sides of the drawer and the thermal insulation below the one or more compartments.

6. The device of claim 5, wherein the more than one actuator comprises more than one solenoid.

7. The device of claim 5, wherein the one or more actuators are mounted to one or more printed circuit boards that are also disposed outside the interior of the drawer defined by the thermal insulation at the sides of the drawer and the thermal insulation below the one or more compartments.

8. The apparatus of claim 7, further comprising one or more lights respectively corresponding to at least some of the one or more compartments, and wherein the controller is configured to, upon determining that a particular compartment is to be accessed:

actuating one of the actuators corresponding to the particular compartment to unlock the particular compartment; and

one of the lamps corresponding to the particular compartment is illuminated.

9. The device of claim 8, further comprising an override mechanism accessible from outside the drawer that mechanically moves the one or more actuators to manually unlock the compartment.

10. The device of claim 1, further comprising an insulating plate within the cabinet, wherein the insulating plate is positioned at a top side of the drawer when the drawer is closed and within the cabinet, and remains within the cabinet when the drawer is open.

11. The device of claim 1, further comprising a top insulating plate coupled to the drawer, wherein the top insulating plate is slidable relative to the drawer to expose the one or more compartments.

12. The device of claim 1, further comprising one or more additional drawers, at least one of which is uncooled.

13. A drawer, comprising:

a housing;

a thermal insulator inside the enclosure and defining a climate controlled interior of the drawer, the thermal insulator and the enclosure together defining a plenum;

a refrigeration system within the drawer, the refrigeration system comprising a thermoelectric cooling unit (TEC) enclosed in a protective enclosure, the protective enclosure having a top and a bottom, the bottom of the protective enclosure being connected to the plenum, the refrigeration system configured to maintain one or more compartments in the drawer at a temperature below a temperature of an ambient environment of the drawer;

a fan, wherein the fan pushes air through the refrigeration system from outside the drawer;

a divider defining one or more compartments within the climate controlled interior of the drawer;

one or more covers covering the one or more compartments;

an electrical interface for receiving power and control signals; and

one or more actuators coupled to the one or more lids to lock and unlock the one or more compartments in response to control signals received via the electrical interface;

Wherein the drawer defines an air flow path through the plenum and the protective cover, and the fan pushes air through the air flow path, the plenum being open to the environment surrounding the drawer on the front side of the drawer such that air enters the plenum at the front of the drawer and into the drawer, and the fan vents the air from the protective cover at the rear of the drawer, and wherein the air flow path is defined at least in part between the thermal insulation and the housing and below the climate-controlled interior of the drawer.

14. The drawer of claim 13, wherein the one or more actuators are disposed outside of the climate controlled interior of the drawer.

15. The drawer of claim 13, further comprising one or more lights corresponding to the one or more compartments, the lights being responsive to control signals received via the electrical interface.

16. The drawer according to claim 13, further comprising:

an air inlet at a front of the drawer;

an air flow channel disposed at least partially within an insulating panel below the climate controlled interior of the drawer, the air flow channel defining the air flow path; and

Wherein the fan draws air into the air inlet, through the air flow passage and through the condenser.

17. The drawer of claim 16, wherein the air inlet is hidden within a handle of the front side of the drawer.

18. A drawer, comprising:

a housing;

a thermal insulator inside the housing and defining an insulated interior of the drawer, the thermal insulator and the housing together defining a plenum;

an air inlet on a first side of the drawer;

an air outlet on a second side of the drawer, the air outlet being located on the protective cover; and

a fan;

wherein the fan draws air into the air inlet and expels air from the air outlet and between the air inlet and the air outlet, the air flowing through an air flow path through the plenum and the protective cover; and is also provided with

Wherein the drawer defines the air flow path through the plenum and the protective cover, and the fan pushes air through the air flow path, the plenum being open to the environment surrounding the drawer on the front side of the drawer such that air enters the air flow path at the front of the drawer and into the plenum, and the fan vents the air from the protective cover on the rear of the drawer, and wherein the air flow path is at least partially defined between the thermal insulation and the housing and below the insulating interior of the drawer.

19. The drawer of claim 18, wherein the first side of the drawer is a front of the drawer, and wherein the air inlet is hidden within a handle of the front side of the drawer.

20. The apparatus of claim 1, wherein the refrigeration system further comprises a fan configured to circulate air within the drawer.

21. The apparatus of claim 1, wherein the refrigeration system further comprises a fan configured to both remove heat from the thermoelectric cooling unit and induce air flow under or around the thermal insulation of the drawer.

22. The device of claim 20, wherein at least some of the compartments are defined in part by perforated walls that allow circulated air to pass through the perforated walls and through the compartments.

23. The device of claim 22, wherein the cover of at least some compartments whose walls are perforated includes a descending rib that protrudes into the compartment when the cover is closed.

24. The device of claim 23, further comprising a computer controller coupled to the drawer, the controller controlling access to the drawer.

25. The device of claim 24, further comprising a temperature probe within the drawer, wherein the temperature probe provides a signal to the computer controller indicative of the temperature within the drawer.

26. The device of claim 24, further comprising one or more actuators controllable by the computer controller and coupled to lids of respective ones of the one or more compartments, wherein the one or more actuators are disposed outside an interior of the drawer defined by the thermal insulation at the sides of the drawer and the thermal insulation below the one or more compartments.

27. The device of claim 24, further comprising magnetic latches on at least some of the compartments, the magnetic latches controlled by the computer controller to lock and unlock the covers of their respective compartments.

28. The device of claim 27, wherein each of the magnetic latches comprises a permanent magnet fixed to the lid of the respective compartment, and an electromagnet fixed to a wall of the compartment such that the permanent magnet contacts the electromagnet when the lid is closed;

and wherein the controller unlocks the compartment by passing an electric current through the electromagnet, thereby causing the electromagnet to repel the permanent magnet.

29. The device of claim 26, wherein the more than one actuator comprises more than one solenoid.

30. The device of claim 26, further comprising one or more sensors configured to sense a position of a lid of a respective compartment of the one or more compartments.

31. The device of claim 30, wherein each of the sensors is disposed outside the interior of the drawer defined by the thermal insulation at the side of the drawer and the thermal insulation below the one or more compartments and is coupled to its respective lid.

32. The device of claim 31, wherein each of the sensors is coupled to its respective lid via a link through the thermal insulation of the drawer.

33. The device of claim 31, wherein each of the sensors is coupled to its respective cover via a jacketed cable passing through the thermal insulation of the drawer.

34. The apparatus of claim 26, further comprising one or more lights respectively corresponding to at least some of the one or more compartments, and wherein the controller is configured to, upon determining that a particular compartment is to be accessed:

one of the lamps corresponding to the particular compartment is illuminated.

35. The device of claim 26, further comprising an override mechanism accessible from outside the drawer that mechanically moves the one or more actuators to manually unlock one or more of the compartments.

36. The apparatus of claim 1, wherein the refrigeration system comprises a closed cooling circuit containing a heat transfer fluid.

37. The apparatus of claim 36, wherein the heat transfer fluid is maintained under pressure such that its boiling point approaches a desired temperature of the interior of the drawer.

38. The apparatus of claim 37, wherein the heat transfer fluid is maintained under pressure such that its boiling point is between 2 ℃ and 8 ℃.

39. The apparatus of claim 36, wherein the heat transfer fluid is carbon dioxide.

40. The apparatus of claim 36 wherein the refrigeration system including the closed cooling loop and the heat transfer fluid forms a heat pipe operating by natural convection.

41. A drawer, comprising:

a housing;

a thermal insulation inside the enclosure, the thermal insulation defining a climate controlled interior of the drawer, the thermal insulation of the drawer and the enclosure together defining a plenum;

a thermoelectric cooling system disposed in a side wall of the drawer and configured to maintain an interior of the drawer at a temperature less than an ambient temperature surrounding the drawer, the thermoelectric cooling system enclosed in a protective enclosure having a top and a bottom, the bottom of the protective enclosure being connected to the plenum;

A set of walls defining one or more compartments within the climate controlled interior of the drawer;

one or more covers covering the one or more compartments;

an electrical interface for receiving power and control signals;

one or more actuators coupled to the one or more lids to lock and unlock the one or more compartments in response to control signals received via the electrical interface; and

a fan, wherein the fan pushes air from outside the drawer through the thermoelectric cooling system,

wherein the drawer defines an air flow path through the plenum and the protective cover, and the fan pushes air through the air flow path, the plenum being open to the environment surrounding the drawer on the front side of the drawer such that air enters the air flow path at the front of the drawer and into the plenum, and the fan vents the air from the protective cover on the rear of the drawer, and wherein the air flow path is at least partially defined between the thermal insulation and the housing and below the one or more compartments.

42. The drawer of claim 41, wherein the one or more actuators are disposed outside of the climate controlled interior of the drawer.

43. The drawer of claim 41, further comprising one or more lights corresponding to the one or more compartments, the lights being responsive to control signals received via the electrical interface.

44. The drawer of claim 41, wherein the thermoelectric cooling system is configured to circulate cooled air in the interior of the drawer.

45. The drawer of claim 41, wherein the thermoelectric cooling system comprises a closed cooling loop containing a heat transfer fluid.

46. The drawer of claim 45, wherein the heat transfer fluid is carbon dioxide, which is maintained at a pressure such that its boiling point is between 2 ℃ and 8 ℃.