JP7569290B2 - Vacuum cleaner - Google Patents

Description

An embodiment of the present invention relates to a vacuum cleaner.

There is a known vacuum cleaner equipped with a switch that automatically stops the rotation of the rotating brush when the suction mouth body is separated from the surface to be cleaned. When the suction mouth body is in contact with the surface to be cleaned, the switch is on, and when the suction mouth body is separated from the surface to be cleaned, the switch is off.

When the suction mouth body is grounded to the surface to be cleaned, the power supplied to the motor is controlled to be the second power. If the suction mouth body is separated from the surface to be cleaned while this control is being executed, the switch is turned off and the power supply to the motor is cut off. At this time, the current flowing through the motor falls below the reference current. When the current flowing through the motor falls below the reference current, the power supplied to the motor is controlled to be the first power which is smaller than the second power. When the suction mouth body is grounded to the surface to be cleaned while this control is being executed and the switch is turned on, the power supplied to the motor is controlled to be the first power. When the current flowing through the motor reaches the first current and exceeds the reference current, the power supplied to the motor is controlled to be the second power which is larger than the first power.

In other words, in conventional vacuum cleaners, when the rotating brush is restarted following the grounding of the suction mouth body, the power supplied to the motor is reduced from the second power to the first power, thereby suppressing the inrush current generated in the motor.

JP 2019-92831 A

Typical examples of contact surfaces with which the rotating cleaning body comes into contact are flooring and carpets, including rugs and bath mats. Flooring is smoother than carpets, while rugs and bath mats have long naps and are uneven. As a result, the rotational resistance between the flooring and the rotating cleaning body is relatively small, while the rotational resistance between the carpet and the rotating cleaning body is extremely large compared to the rotational resistance between the flooring and the rotating cleaning body. Therefore, the electric motor must rotate the rotating cleaning body on multiple types of contact surfaces that have different properties in terms of the magnitude of the rotational resistance of the rotating cleaning body.

However, when the power to start the motor is temporarily reduced, as in conventional vacuum cleaners, depending on the type of surface it comes into contact with, the rotational resistance of the rotating cleaning body may be too great, resulting in an insufficient ability for the motor to sweep away dust at low speeds or even a failure to start.

The present invention aims to provide a vacuum cleaner that can reliably start the motor that generates the rotational drive of the rotating cleaning body, regardless of the rotational resistance between the contact surface and the rotating cleaning body.

In order to solve the above-mentioned problems, an electric vacuum cleaner according to an embodiment of the present invention comprises a rotating cleaning body that is rotatably supported, an electric motor that generates a rotational driving force for the rotating cleaning body, a detection unit that detects a physical quantity that can distinguish the magnitude of the rotational resistance of the rotating cleaning body relative to a contacted surface with which the rotating cleaning body is in contact, and a control unit that controls the second input to be larger than the first input, when an input of the electric motor at a first contacted surface having a smaller rotational resistance is defined as a first input and an input of the electric motor at a second contacted surface having a larger rotational resistance than the first contacted surface is defined as a second input, and when the control unit starts the rotating cleaning body that has come into contact with the contacted surface, it temporarily starts the motor with a third input that is larger than the first input, and when the rotating cleaning body separates from the contacted surface while the motor is rotating, it stops the motor, and when the rotating cleaning body comes into contact with the contacted surface again within a predetermined time, it restarts the motor with the input before the stop, and when the rotating cleaning body comes into contact with the contacted surface again after the time has elapsed, it restarts the motor with the third input .

1 is a perspective view of a vacuum cleaner according to an embodiment of the present invention; FIG. 2 is a control block diagram of a suction head body of the vacuum cleaner according to the embodiment of the present invention. 5 is a flowchart showing an example of motor input control executed by the electric vacuum cleaner according to the embodiment of the present invention. 5 is a flowchart showing an example of a restart control of the electric motor executed by the electric vacuum cleaner according to the embodiment of the present invention. 5A to 5C are schematic diagrams for comparing restart control of an electric motor according to an embodiment of the present invention with restart control of a comparative example; 5A to 5C are schematic diagrams for comparing restart control of an electric motor according to an embodiment of the present invention with restart control of a comparative example; 5A to 5C are schematic diagrams for comparing restart control of an electric motor according to an embodiment of the present invention with restart control of a comparative example; 5A to 5C are schematic diagrams for comparing restart control of an electric motor according to an embodiment of the present invention with restart control of a comparative example;

An embodiment of the vacuum cleaner according to the present invention will be described with reference to Figures 1 to 8.

Figure 1 is a perspective view of a vacuum cleaner according to an embodiment of the present invention.

As shown in FIG. 1, the electric vacuum cleaner 1 according to this embodiment is, for example, a stick type or a handheld type. The electric vacuum cleaner 1 includes a handheld vacuum cleaner main body 2, an extension tube 3 that can be attached and detached to the vacuum cleaner main body 2, and a suction port body 5 that can be attached and detached to the extension tube 3.

When a user holds the vacuum cleaner 1 in his/her hand and places the suction mouth body 5 on the floor surface, which is the contact surface, FIG. 1 corresponds to a view of the vacuum cleaner 1 seen from diagonally forward and to the left of the user.

The vacuum cleaner 1 can also be used as a handheld vacuum cleaner with only the vacuum cleaner body 2, with the extension tube 3 and suction mouth body 5 removed. In other words, the vacuum cleaner body 2 can be used alone as a handheld vacuum cleaner. The vacuum cleaner 1 can also be used with a nozzle that is much shorter than the extension tube 3, instead of the extension tube 3 and suction mouth body 5.

The vacuum cleaner body 2 includes a body case 12 having a handle portion 11, an electric blower 13 housed in the body case 12 and generating a negative suction pressure, a dust separation unit 15 removably attached to the body case 12 and fluidly connected to the suction side of the electric blower 13, a suction pipe 16 fluidly connected to the suction side of the electric blower 13 via the dust separation unit 15, a body control unit 17 that mainly controls the electric blower 13, a secondary battery 18 removably attached to the body case 12, and a holding mechanism that removably holds the dust separation unit 15 to the body case 12.

The vacuum cleaner body 2 drives the electric blower 13 using the power stored in the secondary battery 18, generates negative pressure by driving the electric blower 13, and applies the generated negative suction pressure to the separation dust collection section 15. The negative suction pressure acting on the separation dust collection section 15 acts sequentially on the suction pipe 16, the extension pipe 3, and the suction port body 5. The negative suction pressure that reaches the suction port body 5 acts on the suction port 19 of the suction port body 5. The negative suction pressure acting on the suction port 19 sucks air containing dust (hereinafter referred to as "dust-containing air") from the floor surface into the suction port 19. The dust-containing air sucked into the suction port 19 flows into the separation dust collection section 15 through the suction port body 5, the extension pipe 3, and the suction pipe 16. The dust separation and collection unit 15 separates dust from the dust-containing air sucked in by the negative suction pressure, collects and accumulates the dust after separation, and sends the air from which the dust has been separated to the electric blower 13. The electric blower 13 exhausts the air from which the dust has been separated out of the main body case 12.

The vacuum cleaner 1 and vacuum cleaner body 2 are used in various positions depending on the user holding the vacuum cleaner body 2 in their hand. In FIG. 1, the view in the direction of solid arrow P is the plan view (top view), and the view in the opposite direction of solid arrow P is the bottom view. In FIG. 1, the view in the direction of solid arrow F is the front view (front view), and the view in the opposite direction of solid arrow F is the rear view. In FIG. 1, the view in the direction of solid arrow L is the left side view, and the view in the opposite direction of solid arrow L is the right side view. In other words, when a user holds the vacuum cleaner 1 with the extension tube 3 protruding horizontally in front of the user, the front-to-back, up-down, and left-to-right directions of the vacuum cleaner 1 correspond to those of the user.

The main body case 12 houses the electric blower 13 and the control circuit board 21 on which the main body control unit 17 is mounted. The main body case 12 is disposed on the extension line of the extension tube 3 and has a columnar front portion 12a extending along the extension line of the extension tube 3, a central portion 12b hanging diagonally downward and rearward from the front portion 12a, a cylindrical rear portion 12c extending rearward from the lower half of the back surface of the central portion 12b, and a handle portion 11 extending rearward from the upper half of the back surface of the central portion 12b, curving in an arc shape and connecting to the rear end of the upper surface of the rear portion 12c.

The main body case 12 also has a charging socket that supplies charging power to the secondary battery 18. The charging socket is connected to the secondary battery 18 via a charging circuit.

Furthermore, the main body case 12 is equipped with an input unit 22 that is positioned within the range in which a user holding the handle 11 can move their fingers.

The front part 12a and the central part 12b cooperate to detachably hold the separation dust collecting part 15. The separation dust collecting part 15 has a cylindrical appearance overall. The front part 12a and the central part 12b hold the separation dust collecting part 15 with the center line C of the separation dust collecting part 15 parallel to the extension line of the center line of the extension tube 3. When the extension tube 3 and the separation dust collecting part 15 are attached to the main body case 12, the extension line of the center line of the extension tube 3 and the center line C of the separation dust collecting part 15 are arranged on a central vertical section that divides the main body case 12 substantially equally into left and right. This central vertical section passes through the center line of the longitudinal front part 12a and the center line of the cylindrical separation dust collecting part 15. In other words, the longitudinal front part 12a and the cylindrical separation dust collecting part 15 are arranged side by side so that their center lines are parallel.

The front part 12a of the main body case 12 houses the suction pipe 16. The suction pipe 16 is arranged in the longitudinal direction of the extension pipe 3, i.e., on the extension direction of the extension pipe 3, and extends in a tubular shape.

The rear portion 12c of the main body case 12 houses the electric blower 13 and the control circuit board 21. The rear portion 12c has an exhaust port 25 that discharges exhaust air from the electric blower 13 out of the main body case 12.

The central portion 12b of the main body case 12 covers and holds a portion of the rear end of the dust separation and collection unit 15 attached to the front portion 12a, and houses an air passage (not shown) that connects the dust separation and collection unit 15 and the electric blower 13. The central portion 12b is connected to the rear end of the front portion 12a, which extends in a substantially straight line, and bulges diagonally downward and toward the rear of the main body case 12. The central portion 12b has an appearance that slopes downward toward the rear of the main body case 12.

The suction pipe 16 is housed in the front part 12a of the main body case 12 and is supported by the main body case 12. When the separation dust collection unit 15 is attached to the main body case 12, the suction pipe 16 is aligned parallel to the separation dust collection unit 15. The suction pipe 16 is a straight pipe that extends substantially straight without bending. The direction along the center line of the suction pipe 16, the extension direction of the suction pipe 16, and the longitudinal direction of the suction pipe 16 are substantially the same and substantially coincide with the front-to-rear direction of the main body case 12.

The suction pipe 16 has a joint structure to which the extension pipe 3 can be attached and detached. This joint structure is provided at the open end of the suction pipe 16. The suction pipe 16 is the fluid inlet of the vacuum cleaner body 2 and is also a joint that fluidly connects the extension pipe 3 and the separation dust collection section 15. By removing the extension pipe 3 from the vacuum cleaner body 2, the suction pipe 16 functions as a suction port when the vacuum cleaner body 2 is used alone as a handheld vacuum cleaner. The tip of the suction pipe 16 is open to the front of the vacuum cleaner body 2.

The rear end of the suction pipe 16 has a second opening connected to the separation dust collecting section 15. The second opening opens toward the radially outward direction of the suction pipe 16. The second opening opens toward the bottom of the main body case 12 toward the separation dust collecting section 15. The second opening is provided on the bottom surface of the front part 12a of the main body case 12. When the separation dust collecting section 15 is attached to the main body case 12, the bottom surface of the front part 12a closely follows the separation dust collecting section 15. In this state, the second opening is fluidly connected to the separation dust collecting section 15.

The dust separation section 15 is disposed in an L-shaped storage space formed by the front part 12a and the center part 12b of the main body case 12. The dust separation section 15 separates, collects, and accumulates dust from the dust-laden air flowing into the vacuum cleaner body 2, while sending clean air from which dust has been removed to the electric blower 13. The dust separation section 15 is of a centrifugal separation type that separates dust and air by centrifugal separation using the difference in mass between the dust and the air. A filtration separation type filter that filters out dust from the dust-laden air may be provided downstream of the dust separation section 15.

The separation dust collecting section 15 also extends in a cylindrical shape along the front-rear direction of the main body case 12. In other words, the separation dust collecting section 15 is a cylindrical container having a center line C extending in the front-rear direction of the main body case 12. The direction along the center line C of the separation dust collecting section 15, the extension direction of the separation dust collecting section 15, and the longitudinal direction of the separation dust collecting section 15 are substantially the same and substantially coincide with the front-rear direction of the main body case 12. Therefore, the center line C of the separation dust collecting section 15 is substantially parallel to the center line of the suction pipe 16. The separation dust collecting section 15 is also provided next to the suction pipe 16. In other words, the longitudinal direction of the separation dust collecting section 15 follows the longitudinal direction of the suction pipe 16. The diameter of the separation dust collecting section 15 is larger than the diameter of the suction pipe 16, and the separation dust collecting section 15 protrudes in the left-right direction (width direction) of the vacuum cleaner main body 2 beyond the suction pipe 16 and the front part 12a of the main body case 12. The left-right direction (width direction) of the vacuum cleaner body 2 corresponds to the normal direction of an imaginary plane that substantially includes the center line C of the cylindrical separation dust collection unit 15 and the center line of the suction pipe 16, or the normal direction of an imaginary plane that substantially passes through the center line C of the cylindrical separation dust collection unit 15 and the center line of the suction pipe 16. This imaginary plane also corresponds to the central vertical cross section of the vacuum cleaner body 2.

The holding mechanism includes a first mechanism that detachably connects one end of the separation dust collecting unit 15 to the main body case 12, and a second mechanism that detachably connects the other end of the separation dust collecting unit 15 to the main body case 12.

The first mechanism is a mechanism that connects the separation dust collecting unit 15 and the main body case 12 by hooking a protrusion provided on the main body case 12 onto a recess provided on the separation dust collecting unit 15. The recess and protrusion of the first mechanism become hooked or detached depending on the change in the relative positions of the separation dust collecting unit 15 and the main body case 12.

The convex portion of the first mechanism is provided at the front end of the bottom surface of the front portion 12a of the main body case 12. The concave portion of the first mechanism is located at one end of the dust separation and collection unit 15, in a position that fits the convex portion.

The second mechanism is a locking mechanism that connects the separation dust collecting unit 15 and the main body case 12 by hooking a convex portion provided on the separation dust collecting unit 15 with a concave portion provided on the main body case 12. Unlike the first mechanism, the second mechanism has an operating piece that can remove the convex portion from the concave portion while maintaining the relative positions of the separation dust collecting unit 15 and the main body case 12. The operating piece is provided on the separation dust collecting unit 15, and the convex portion of the second mechanism is integrated with the operating piece.

The recess of the second mechanism is provided at the bottom of the central portion 12b of the main body case 12, that is, at the portion furthest from the suction pipe 16 in the radial direction of the suction pipe 16. The protrusion of the second mechanism is located at the other end of the separation dust collecting section 15, in a position that fits the recess. The recess of the first mechanism and the protrusion of the second mechanism are both provided in the separation dust collecting section 15, and are disposed substantially symmetrically with respect to the longitudinal center and the lateral center of the separation dust collecting section 15. In addition, the protrusion of the second mechanism is disposed at the portion furthest from the recess of the first mechanism within the separation dust collecting section 15.

The operating piece is capable of performing operations involving mechanical movement, including sliding and swinging, and is part of various mechanisms that convert the movement associated with this operation into a movement that disengages the convex portion from the concave portion. For example, the user can slide the operating piece to disengage the convex portion of the second mechanism from the concave portion. Furthermore, when the operating piece is not being operated by the user, it moves the convex portion of the second mechanism to a position where it hooks into the concave portion.

When the dust separation unit 15 is attached to the main body case 12, the first mechanism hooks the convex part on the concave part to connect the dust separation unit 15 to the main body case 12, and the second mechanism hooks the convex part on the concave part to connect the dust separation unit 15 to the main body case 12. When the operating piece is operated and the convex part of the second mechanism comes out of the concave part of the second mechanism, the second mechanism is unlocked. At this time, the convex part of the first mechanism remains hooked on the concave part. Then, with the second mechanism unlocked, the user uses the first mechanism as a fulcrum to move the other end of the dust separation unit 15 away from the main body case 12. Then, the dust separation unit 15 moves away from the main body case 12, and eventually the convex part of the first mechanism comes out of the concave part and the first mechanism is unlocked.

When the dust separation unit 15 is detached from the main body case 12, first the convex part of the first mechanism is hooked into the concave part. With the first mechanism locked, the user uses the first mechanism as a fulcrum to bring the other end of the dust separation unit 15 closer to the main body case 12. Then, the dust separation unit 15 is attached to the main body case 12, and eventually the convex part of the second mechanism is hooked into the concave part, and the second mechanism is also locked.

In this embodiment, the dust collector 15 is attached to and detached from the main case 12 while moving along an arcuate path, but may be attached and detached while moving along a straight path in the radial direction of the suction pipe 16. In this case, it is preferable that the first mechanism and the second mechanism are locked and unlocked substantially simultaneously. The direction in which the dust collector 15 moves when the dust collector 15 is attached to and detached from the main case 12 may be a direction intersecting the longitudinal direction of the suction pipe 16. Therefore, when the dust collector 15 is attached to the main case 12, the dust collector 15 moves toward the suction pipe 16 in the radial direction of the suction pipe 16, and when the dust collector 15 is detached from the main case 12, the dust collector 15 moves away from the suction pipe 16 in the radial direction of the suction pipe 16.

The central portion 12b of the main body case 12 is provided with a connection port that is fluidly connected to the exhaust side of the separation dust collection unit 15, and a separation unit downstream air duct that fluidly connects the connection port to the electric blower 13. The central portion 12b includes a portion that is sandwiched between the separation dust collection unit 15 and the rear portion 12c of the main body case 12. The connection port and the separation unit downstream air duct are located in this portion.

The connecting port is located at a position facing the front of the central portion 12b. When the separation dust collecting unit 15 is attached to the main body case 12, the connecting port faces directly at the rear end face of the separation dust collecting unit 15. Therefore, when the separation dust collecting unit 15 is attached to the main body case 12, the connecting port is located on an extension of the center line C of the separation dust collecting unit 15.

The suction side of the electric blower 13 is connected to the separation dust collection section 15 via a connecting port and a separation section downstream air duct. The electric blower 13 draws in air from the separation dust collection section 15 to generate suction negative pressure. The electric blower 13 includes an impeller, an electric motor that generates a rotational driving force for the impeller, and a rotating shaft that transmits the rotational driving force from the electric motor to the impeller.

The impeller is, for example, a turbofan, and is equipped with multiple blades. Each blade has a twisted shape that gradually rises in the radial direction of the hub from the center of the conical hub toward the outer edge of the hub. In other words, each blade is a so-called three-dimensional blade, in which the airfoil or wing section changes from the leading edge to the trailing edge. The impeller is covered by a case that has an intake port.

The electric blower 13 has a cylindrical or columnar shape with the rotation axis at its center. It is housed in the main body case 12 with the center line of the rotation axis facing the front-to-rear direction of the main body case 12 and the suction port facing forward. In addition, the center line of the rotation axis of the electric blower 13 is substantially positioned on the extension line C of the separation dust collection section 15.

The rear portion 12c of the main body case 12 houses the control circuit board 21 on which the main body control unit 17 is mounted. The control circuit board 21 is located directly behind the electric blower 13.

The main body control unit 17 includes a microprocessor and a storage device that stores various calculation programs executed by the microprocessor, parameters, and the like. The storage device stores various settings, i.e., arguments, related to a number of pre-set operating modes. The multiple operating modes are associated with the output of the electric blower 13. Each operating mode is set with a different input value, i.e., an input value for the electric blower 13, which is a target value of the current flowing through the electric blower 13. Each operating mode is associated with an operation input received by the input unit 22. The main body control unit 17 selects an arbitrary operating mode corresponding to the operation input to the input unit 22 from a number of pre-set operating modes, reads out the setting of the selected operating mode from the storage device, and operates the electric blower 13 according to the setting of the read operating mode.

The rear portion 12c of the main body case 12 is positioned on an extension of the center line C of the separation dust collection unit 15 when the separation dust collection unit 15 is attached to the main body case 12.

The secondary battery 18 is also called a storage battery, a rechargeable battery, and a rechargeable battery. The secondary battery 18 stores the power consumed by the electric blower 13 and the main body control unit 17. The secondary battery 18 is removably attached to the bottom of the rear part 12c of the main body case 12. The secondary battery 18 may be fixed so that it cannot be removed. By preparing multiple secondary batteries 18, the removable secondary battery 18 can be replaced as needed. If the charge rate of the secondary battery 18 attached to the vacuum cleaner 1 decreases, the secondary battery 18 can be replaced with a charged secondary battery 18, allowing the vacuum cleaner 1 to continue operating.

The vacuum cleaner 1 may also use a primary battery as a power source instead of the secondary battery 18.

The handle portion 11 is integrally provided on the main body case 12. The handle portion 11 is the part that the user holds with his/her hand in order to clean the floor surface with the vacuum cleaner 1. Therefore, it is preferable that the handle portion 11 has an appropriate shape that is easy to hold with human fingers.

The handle 11 is installed between the front 12a and rear 12c of the main case 12. The handle 11 extends from the rear end of the front 12a in the extension direction of the extension tube 3 and is curved in an arc to connect to the rear end of the rear 12c. A continuous space runs through the main case 12 in the left-right direction (width direction) between the handle 11 and the back surface of the central portion 12b of the main case 12, and between the handle 11 and the top surface of the rear 12c of the main case 12. The fingers of the user gripping the handle 11, primarily the index finger, middle finger, ring finger, and little finger, are positioned in this space.

The input unit 22 is provided on the top surface of the front end of the handle 11 so that a user holding the handle 11 can easily operate it with their thumb.

The input unit 22 includes an operation start switch 22a that receives an operation to start the electric blower 13, and an operation stop switch 22b that receives an operation to stop the electric blower 13. The operation start switch 22a and the operation stop switch 22b are electrically connected to the main body control unit 17. The user of the electric vacuum cleaner 1 can select one of the operation modes of the electric blower 13 by operating the input unit 22. The operation start switch 22a also functions as a changeover switch for the operation mode while the electric blower 13 is in operation. In this case, the main body control unit 17 switches the operation mode in the following order each time it receives an operation signal from the operation start switch 22a. In other words, the operation start switch 22a commands at least one of starting the electric blower 13 and changing the operation output of the electric blower 13. Instead of the operation start switch 22a, the input unit 22 may be provided with a strong operation switch (not shown), a medium operation switch (not shown), and a weak operation switch (not shown) separately.

The extension tube 3 and suction port body 5 suck in dust on the floor surface together with air using the negative pressure applied by the electric blower 13 and guide it to the vacuum cleaner body 2.

The extension tube 3 is fluidly connected to the suction side of the electric blower 13 via the suction tube 16 and the separation dust collection section 15 of the vacuum cleaner body 2. The extension tube 3 has a length that substantially reaches the floor surface when the user is holding the handle section 11 of the vacuum cleaner body 2. One end of the extension tube 3 is provided with a joint structure that can be attached and detached to the suction tube 16 of the vacuum cleaner body 2. The other end of the extension tube 3 is provided with a joint structure that can be attached and detached to the suction port body 5. The extension tube 3 may or may not be extendable.

The suction mouth body 5 can run or slide freely on a floor surface such as a wooden floor or carpet, and has a suction mouth 19 on the bottom surface that faces the floor surface when running or sliding. The suction mouth body 5 also has a rotatable rotating cleaning body 28 arranged at the suction mouth 19, and an electric motor 29 as a drive source for driving the rotating cleaning body 28. One end of the suction mouth body 5 is provided with a joint structure that can be attached and detached to the other end of the extension tube 3. The suction mouth body 5 is fluidly connected to the suction side of the electric blower 13 via the extension tube 3, the suction tube 16, and the separation dust collection unit 15. The suction mouth body 5, the extension tube 3, the suction tube 16, and the separation dust collection unit 15 are an intake air passage that runs from the suction mouth 19 to the electric blower 13.

When the operation start switch 22a is operated, the vacuum cleaner 1 starts the electric blower 13. For example, when the operation start switch 22a is operated while the electric blower 13 is stopped, the vacuum cleaner 1 first starts the electric blower 13 in strong operation mode, and when the operation start switch 22a is operated again, the operation mode of the electric blower 13 is changed to medium operation mode, and when the operation start switch 22a is operated a third time, the operation mode of the electric blower 13 is changed to weak operation mode, and so on. The strong operation mode, medium operation mode, and weak operation mode are a plurality of operation modes that are set in advance. The input value for the electric blower 13 is the largest in the strong operation mode and the smallest in the weak operation mode. When the electric blower 13 is started, it sucks air from the separation dust collection section 15 and creates a negative pressure in the separation dust collection section 15.

The negative pressure in the dust separation section 15 acts on the suction port 19 through the suction pipe 16, extension pipe 3, and suction port body 5 in sequence. The vacuum cleaner 1 uses the negative pressure acting on the suction port 19 to suck in dust on the floor together with air, cleaning the floor. The dust separation section 15 separates and accumulates dust from the dust-containing air sucked into the vacuum cleaner 1, while sending the air separated from the dust-containing air to the electric blower 13. The electric blower 13 exhausts the air sucked in from the dust separation section 15 to the outside of the vacuum cleaner body 2.

Figure 2 is a control block diagram of the suction mouth body of a vacuum cleaner according to an embodiment of the present invention.

As shown in FIG. 2, the suction mouth body 5 according to this embodiment drives an electric motor 29 with power supplied from a secondary battery 18 attached to the vacuum cleaner body 2. The suction mouth body 5 includes a rotating cleaning body 28, an electric motor 29 that generates a driving force for rotating the rotating cleaning body 28, and a suction mouth body control unit 41 that controls the operation of the electric motor 29.

The rotating cleaning body 28 has a shaft and numerous brush bristles extending radially from the shaft. When the suction port body 5 is in contact with the floor surface, a part of the rotating cleaning body 28 that protrudes outward from the suction port 19 of the suction port body 5, i.e., some of the brush bristles, come into contact with the floor surface. Therefore, when the suction port body 5 is in contact with the floor surface and the motor 29 rotates the rotating cleaning body 28, the tips of the brush bristles wipe the floor surface one after another due to the rotation of the rotating cleaning body 28. When the suction port body 5 is away from the floor surface, the rotating cleaning body 28 also moves away from the floor surface.

The suction port body control unit 41 is electrically connected to the secondary battery 18 by two electric wires 45 that pass through the extension tube 3 and reach the vacuum cleaner body 2. One of the two electric wires 45 is a grounded electric wire 46, and the other of the two electric wires 45 is a non-grounded electric wire 47. The suction port body control unit 41 may be mounted on the control circuit board 21 in the body case 12 together with the body control unit 17. In other words, the suction port body control unit 41 may be provided in the vacuum cleaner body 2.

The suction port body control unit 41 starts the electric motor 29 when the operation start switch 22a is operated. The vacuum cleaner 1 may be provided with a motor switch separate from the operation start switch 22a that commands at least one of starting the electric motor 29 and changing the operating output of the electric motor 29. In that case, the suction port body control unit 41 starts the electric motor 29 when the motor switch is operated.

The suction port body control unit 41 includes a control power generation circuit 51 that steps down the power supplied from the secondary battery 18 and outputs power for control, a reference voltage generation circuit 52 that outputs a reference voltage, a drive circuit 53 for the electric motor 29, a current detection circuit 55 that detects the current flowing through the electric motor 29, a current limiting circuit 56 that limits the current flowing through the electric motor 29, and a switch 57 that opens and closes the power supply path connected to the electric motor 29.

The reference voltage generating circuit 52 is a square wave that instructs the current limiting circuit 56 to rise.

The current detection circuit 55 outputs a voltage value that correlates with the detection result of the current flowing through the electric motor 29 to the current limiting circuit 56. The current detection circuit 55 includes a shunt resistor that converts the current flowing through the electric motor 29 into a voltage, and an amplifier circuit that amplifies the voltage converted by the shunt resistor and outputs it to the corresponding current limiting circuit 56. The amplifier circuit is a so-called differential amplifier circuit.

The current limiting circuit 56 generates a square wave for switching the switching element of the drive circuit 53 based on the falling voltage value timing of the square wave based on the output voltage of the current detection circuit 55 and the rising timing of the square wave output by the reference voltage generation circuit 52. In other words, the current limiting circuit 56 increases or decreases the duty ratio of the PWM signal for driving the drive circuit 53.

The drive circuit 53 includes a switching element that switches the power input to the electric motor 29. The drive circuit 53 opens and closes the switching element using pulse width modulation control. The switching element opens and closes the non-grounded electric wire 47 that supplies drive power from the secondary battery 18 to the corresponding electric motor 29. The switching element is an element such as a metal-oxide-semiconductor field-effect transistor (MOSFET). The switching element has a gate that is connected to a corresponding current limiting circuit 56. The switching element changes the input (drive current) of the electric motor 29 in response to changes in the gate current or gate voltage.

The switch 57 is part of a safety device 58 that cuts off the power supply to the motor 29 and stops the rotation of the rotary cleaning body 28 when the suction mouth body 5 is separated from the floor surface. The safety device 58 includes the switch 57 and a ground detection unit 61 that can change the amount of protrusion of the suction mouth body 5 from the bottom surface and detects whether the suction mouth body 5 is grounded on the floor surface. When the ground detection unit 61 detects that the bottom surface of the suction mouth body 5 is grounded on the floor surface, the safety device 58 closes the switch 57 to allow the power supply to the motor 29, and when the ground detection unit 61 detects that the suction mouth body 5 is separated from the bottom surface, the safety device 58 opens the switch 57 to cut off the power supply to the motor 29. The safety device 58 also opens the switch 57 to cut off the power supply to the motor 29 when the bottom surface of the suction mouth body 5 is facing upward.

Now, flooring and carpet are known as typical examples of floor surfaces that are contact surfaces with which the rotating cleaning body 28 comes into contact. Flooring is smoother than carpet, which is generally fuzzy and uneven. Therefore, the rotational resistance between the flooring and the rotating cleaning body 28 is relatively small, and the rotational resistance between the carpet and the rotating cleaning body 28 is extremely large compared to the rotational resistance between the flooring and the rotating cleaning body 28. Therefore, the electric motor 29 must rotate the rotating cleaning body 28 on multiple types of floor surfaces that have different properties in terms of the magnitude of the rotational resistance of the rotating cleaning body 28.

Figure 3 is a flowchart showing an example of motor input control performed by an electric vacuum cleaner according to an embodiment of the present invention.

As shown in FIG. 3, the current limiting circuit 56 of the vacuum cleaner 1 according to this embodiment estimates the magnitude of the rotational resistance of the rotating cleaning body 28, i.e., the load torque of the motor 29, from the output result of the current detection circuit 55, i.e., the current value flowing through the motor 29, when the motor 29 is rotating and driving, and increases or decreases the power supplied to the motor 29 by estimating the type of floor surface with which the rotating cleaning body 28 is in contact. The current detection circuit 55 functions as a detection unit that detects the current value flowing through the motor 29 as a physical quantity that can determine the magnitude of the rotational resistance of the rotating cleaning body 28 relative to the contact surface with which the rotating cleaning body 28 is in contact. For example, in the case of flooring with low rotational resistance, the current limiting circuit 56 keeps the power supplied to the motor 29 low, and in the case of carpet with high rotational resistance, the current limiting circuit 56 increases the power supplied to the motor 29.

Here, the flooring, which has a small rotational resistance of the rotating cleaning body 28, is the first contacted surface, the carpet, which has a large rotational resistance of the rotating cleaning body 28, is the second contacted surface, the input of the electric motor 29 when rotating the rotating cleaning body 28 in contact with the flooring is the first input, and the input of the electric motor 29 when rotating the rotating cleaning body 28 in contact with the carpet is the second input. At that time, the rotational resistance between the rotating cleaning body 28 and the second contacted surface is greater than the rotational resistance between the rotating cleaning body 28 and the first contacted surface, and the second input of the electric motor 29 that rotates the rotating cleaning body 28 in contact with the second contacted surface is greater than the first input of the electric motor 29 that rotates the rotating cleaning body 28 in contact with the first contacted surface.

Specifically, the current limiting circuit 56 determines whether the current value of the motor 29 is greater than zero (step S1). If the motor 29 is rotating the rotating cleaning body 28, step S1 is answered yes. If the switch 57 of the safety device 58 is open and power is not being supplied to the motor 29, or if the suction port body 5 is not attached, step S1 is answered no (step S1 No), and the process is repeated.

If step S1 is positive (step S1 Yes), the current limiting circuit 56 estimates the type of floor surface that the rotating cleaning body 28 is in contact with based on the current value flowing through the motor 29 (step S2). The type of floor surface in step S2 is estimated based on multiple conditions. For example, the first condition is the current magnitude of the current value flowing through the motor 29. The second condition is the magnitude of the change in the current value flowing through the motor 29 from a time going back a predetermined floor surface estimation time to the present, for example, 3 seconds. If the current value of the current value flowing through the motor 29 continues to be equal to or greater than a predetermined threshold value for a certain period of time as the first condition, and if the change in the current value flowing through the motor 29 from a time going back a predetermined floor surface estimation time to the present is equal to or greater than a predetermined second threshold value as the second condition, the type of floor surface that the rotating cleaning body 28 is in contact with is estimated to be carpet, which is the second surface to be cleaned. If either one of the conditions is not met, the type of floor surface that the rotating cleaning body 28 is in contact with is estimated to be flooring, which is the first surface to be cleaned.

In other words, the current limiting circuit 56 distinguishes between floor surfaces with different rotational resistances under multiple conditions and controls the magnitude of the input to the motor 29.

The method of estimating the type of floor surface that the rotating cleaning body 28 is in contact with is not limited to the method based on the current flowing through the motor 29. The current limiting circuit 56 can use a known floor surface estimation method. For example, a method of estimating the type of floor surface that the suction body 5 is in contact with by capturing an image of the periphery of the suction body 5 with a camera and analyzing the captured image may be adopted. Because flooring reflects light more easily than carpeting, the type of floor surface can be estimated by analyzing the image captured by the camera. In addition, a method of arranging a light transmitter and a light receiver around the suction body 5 and estimating the type of floor surface from the amount of light received by the light receiver may be adopted. Because flooring reflects light more easily than carpeting, the type of floor surface can be estimated from the reflectance.

If the type of floor surface estimated in step S2 is the second contact surface (step S3 Yes), the current limiting circuit 56 sets the power supplied to the motor 29 to the second input (step S4) and returns to step S1 to repeat the process. In other words, it determines that the rotating cleaning body 28 is in contact with carpet, which is the second contact surface with high rotational resistance, and sets the power supplied to the motor 29 to a large value. On the other hand, if the type of floor surface estimated in step S2 is not the second contact surface (step S3 No), the current limiting circuit 56 sets the power supplied to the motor 29 to the first input (step S5) and returns to step S1 to repeat the process. In other words, it determines that the rotating cleaning body 28 is in contact with flooring, which is the first contact surface with low rotational resistance, and sets the power supplied to the motor 29 to a small value.

The magnitude relationship between the rotational resistance of the first contacted surface, the rotational resistance of the second contacted surface, the first input, and the second input is not limited to flooring and carpet, which are specific examples of contacted surfaces. In other words, the current limiting circuit 56 sets the input of the motor 29 to be larger as the rotational resistance of the rotating cleaning body 28 increases. Such input control of the motor 29 may target three or more types of contacted surfaces. In addition, the input control of the motor 29 may be changed in stages for each type of contacted surface, or may be changed continuously and linearly according to the rotational resistance of the rotating cleaning body 28.

Also, if step S1 is negative (step S1 No) and a predetermined stop duration has elapsed, the current limiting circuit 56 may control the switching element of the drive circuit 53 to cut off the power supply to the electric motor 29.

When the suction mouth body 5 leaves the floor surface and the switch 57 of the safety device 58 opens, the power supply to the motor 29 is cut off and the motor stops. When the suction mouth body 5 touches the floor surface again and the switch 57 of the safety device 58 closes, the motor receives power and restarts.

In conventional vacuum cleaners, the power supplied to the motor is reduced to a first power smaller than the reference current in order to prevent the inrush current from becoming excessive when the motor is restarted. Therefore, for example, if the rotating cleaning body is in contact with a floor surface with high rotational resistance such as a carpet, the restart of the motor is hindered, and the motor may rotate at a low speed and may not be able to sufficiently scrape out dust, or may remain stopped. If the restart of the motor is hindered, the current value flowing through the motor instantly rises to several times higher than the reference current, exceeding the abnormal current that may lead to the motor burning out if left unattended, so the control unit forcibly cuts off the power supply to the motor. Therefore, the second power larger than the first power is not supplied, making it increasingly difficult to restart the motor. Moreover, the suction port body 5 once separated from the floor surface is not necessarily grounded again on a floor surface of the same nature. For example, after leaving flooring with low rotational resistance, it may be grounded again on carpet with high rotational resistance.

Figure 4 is a flowchart showing an example of motor restart control executed by an electric vacuum cleaner according to an embodiment of the present invention.

As shown in FIG. 4, when starting the rotating cleaning body 28 that is in contact with the contacted surface, the suction port body control unit 41 of the vacuum cleaner 1 according to this embodiment starts the motor 29 temporarily with a third input that is greater than the first input.

The suction port body control unit 41 also stops the motor 29 if the rotating cleaning body 28 leaves the floor surface while the motor 29 is rotating, and restarts the motor 29 with the input before it was stopped if the rotating cleaning body 28 touches the contact surface again within a predetermined first time, while restarting the motor 29 with a third input if the rotating cleaning body 28 touches the floor surface again after the first time has elapsed.

Furthermore, the suction port body control unit 41 distinguishes floor surfaces with different rotational resistances under multiple conditions and controls the magnitude of the input to the motor 29, while relaxing the conditions to distinguish floor surfaces with different rotational resistances within a second predetermined time period after starting the motor with a third input.

Specifically, when the suction port body 5 is lifted off the floor and the switch 57 of the safety device 58 opens (step S11: Yes), the suction port body control unit 41 starts timing the first timer (step S12). At this time, the power supply to the electric motor 29 is cut off and the electric motor 29 stops.

Next, when the first timer exceeds a predetermined first time (step S13: Yes), the suction port body control unit 41 sets the input supplied to the electric motor 29 to the third input (step S14). When step S14 is executed, information indicating that the input supplied to the electric motor 29 has been set to the third input, a so-called flag, is set.

The third input preferably encompasses the properties of floor surfaces that may come into contact with the rotating cleaning body 28, and is preferably an input value that allows the motor 29 to start even on a floor surface with the greatest rotational resistance. For example, if one considers only flooring as the first contact surface and carpet as the second contact surface, it is sufficient if the motor 29 can be started with the rotating cleaning body 28 in contact with the carpet. In such a case, if the third input is equal to or greater than the second input, the motor 29 can be reliably started regardless of whether the rotating cleaning body 28 is in contact with flooring or carpet.

In addition, if the first timer is within the predetermined first time (No in step S13), the suction port body control unit 41 does not change the input supplied to the electric motor 29, and maintains the input immediately before the electric motor 29 was stopped in step S11.

Next, when the suction port body 5 touches the floor surface and the switch 57 of the safety device 58 closes (step S15: Yes), the suction port body control unit 41 starts the second timer (step S16). At this time, the supply of power to the electric motor 29 is resumed and the electric motor 29 restarts.

In other words, if the suction mouth body 5 is lifted up unintentionally due to unevenness of the floor surface (unevenness of a rug or bath mat) or is temporarily lifted to avoid erroneous suction and then touches the floor surface again within a predetermined first hour, the suction mouth body control unit 41 does not change the input to the motor 29 and restarts the motor 29 with the first input or second input, which is the input value immediately before the suction mouth body 5 left the floor surface, whereas if the suction mouth body 5 leaves the floor surface, moves, etc., and then touches the floor surface again after the predetermined first hour has elapsed, the input to the motor 29 is changed to the third input and the motor 29 is restarted.

Note that the first timer and the second timer do not count simultaneously. Therefore, the first timer and the second timer may be the same timer.

The suction port body control unit 41 may also gradually increase the input power of the motor 29 toward the third input power in order to suppress the inrush current to the motor 29 immediately after the switch 57 of the safety device 58 is closed. In this case, it is preferable that the input power of the motor 29 reaches the third input power from a level capable of suppressing the inrush current to the motor 29 within, for example, 0.5 seconds.

Immediately after the electric motor 29 is restarted, the suction port body control unit 41 determines whether information has been set indicating that the input supplied to the electric motor 29 has been set to the third input (step S17).

If the flag indicating that the input supplied to the electric motor 29 is set to the third input is not set (step S17: No), the suction port body control unit 41 transitions to the input control of the electric motor 29 shown in FIG. 3 (step S18) and ends the restart control.

On the other hand, if a flag is set indicating that the input supplied to the electric motor 29 has been set to the third input (step S17: Yes), the suction port body control unit 41 relaxes the floor surface type estimation condition in step S2 of the input control of the electric motor 29 shown in FIG. 3 and executes the input control of the electric motor 29 (step S20) until the second timer passes the predetermined second time (step S19: Yes). Also, when the second timer passes the predetermined second time (step S19: No), the suction port body control unit 41 transitions to the input control of the electric motor 29 shown in FIG. 3 (step S18) and ends the restart control.

Relaxing the estimation conditions in step S20 means excluding at least one of the multiple conditions to determine the type of floor surface. In normal step S2, if the first condition is that the current value of the electric current flowing through the motor 29 remains equal to or greater than a predetermined threshold for a certain period of time, and if the second condition is that the amount of change in the electric current flowing through the motor 29 from a time going back a certain floor surface estimation time to the present time is equal to or greater than a predetermined second threshold, the type of floor surface that the rotating cleaning body 28 is in contact with is estimated to be carpet, which is the second surface to be cleaned. Relaxed estimation conditions, for example, exclude the second condition and estimate the floor surface based only on the first condition. In other words, if the current value of the current flowing through the motor 29 remains equal to or greater than a predetermined threshold value for a certain period of time as the first condition until the second timer reaches a predetermined second time (step S19 Yes), the suction port body control unit 41 estimates that the type of the floor surface that the rotating cleaning body 28 is in contact with is carpet, which is the second surface to be cleaned, and if the first condition is not met, it estimates that the type of the floor surface that the rotating cleaning body 28 is in contact with is hardwood flooring, which is the first surface to be cleaned. Also, when the second timer reaches a predetermined second time (step S19 No), the suction port body control unit 41 returns the estimated conditions of step S2 to the original multiple conditions.

It is preferable that the second time be set to the same as the floor surface estimation time in the second condition of step S2.

Figures 5 to 8 are schematic diagrams comparing the restart control of an electric motor according to an embodiment of the present invention with the restart control of a comparative example.

The restart control in the comparative example starts the motor 29 with a low current to suppress inrush current when the suction mouth body 5 touches the floor surface again, for example, with the first input of the motor 29 when rotating the rotating cleaning body 28 that contacts the flooring in this embodiment.

In addition, in the restart control according to this embodiment shown in Figures 5 to 8, the third input and the second input are set to the same input value.

Figure 5 shows a case where the suction mouth body 5, which is in contact with the carpet, which is the second contact surface, leaves the second contact surface, and then comes back into contact with the flooring, which is the first contact surface, after the first timer exceeds the first time, and the motor 29 restarts.

As shown in FIG. 5, in the comparative example, when the suction mouth body 5 comes back into contact with the first contact surface (flooring), the input power of the motor 29 is reduced from the second input to the first input, and the motor 29 is restarted. In this case, the rotating cleaning body 28 easily restarts against the rotational resistance of the flooring.

In addition, in the vacuum cleaner 1 of this embodiment, when the suction mouth body 5 comes back into contact with the first contact surface (flooring), the input of the motor 29 is changed from the second input to the third input (third input = second input) and the motor 29 is restarted. In this case, too, the rotating cleaning body 28 easily restarts against the rotational resistance of the flooring.

Figure 6 shows a case where the suction mouth body 5, which is in contact with the carpet, which is the second contact surface, leaves the second contact surface, and then comes back into contact with the carpet, which is the second contact surface, after the first timer exceeds the first time, and the motor 29 restarts.

As shown in FIG. 6, in the comparative example, when the suction mouth body 5 touches the second contact surface (carpet) again, the input power of the motor 29 is reduced from the second input to the first input and the motor 29 is restarted. In this case, the rotating cleaning body 28 must be restarted against the rotational resistance of the carpet. Therefore, in the comparative example, the rotating cleaning body 28 cannot rotate against the rotational resistance, and there is a risk that the motor 29 will fail to restart.

On the other hand, in the vacuum cleaner 1 of this embodiment, when the suction mouth body 5 touches the second contact surface (carpet) again, the input of the motor 29 is changed from the second input to the third input (third input = second input) and the motor 29 is restarted. In the vacuum cleaner 1 of this embodiment, the rotating cleaning body 28 easily restarts against the rotational resistance with the carpet.

Figure 7 shows a case where the suction mouth body 5, which is in contact with the first contact surface (flooring), moves away from the first contact surface, and then comes back into contact with the first contact surface (flooring) after the first timer exceeds the first time, causing the motor 29 to restart.

As shown in FIG. 7, in the comparative example, when the suction mouth body 5 comes back into contact with the first contact surface (flooring), the input of the motor 29 is kept at the first input and the motor 29 is restarted. In this case, the rotating cleaning body 28 easily restarts against the rotational resistance of the flooring.

In addition, in the vacuum cleaner 1 of this embodiment, when the suction mouth body 5 comes back into contact with the first contact surface (flooring), the input of the motor 29 is changed from the second input to the third input (third input = second input) and the motor 29 is restarted. In this case, too, the rotating cleaning body 28 restarts very easily against the rotational resistance of the flooring.

Figure 8 shows a case where the suction mouth body 5, which is in contact with the first contact surface (flooring), leaves the first contact surface, and then comes back into contact with the second contact surface (carpet) after the first timer exceeds the first time, causing the motor 29 to restart.

As shown in FIG. 8, in the comparative example, when the suction mouth body 5 touches the second contact surface (carpet) again, the input of the motor 29 is kept at the first input and the motor 29 is restarted. In this case, the rotating cleaning body 28 must be restarted against the rotational resistance of the carpet. Therefore, in the comparative example, the rotating cleaning body 28 cannot rotate against the rotational resistance, and there is a risk that the motor 29 will fail to restart.

On the other hand, in the vacuum cleaner 1 of this embodiment, when the suction mouth body 5 touches the second contact surface (carpet) again, the input of the motor 29 is changed from the first input to the third input (third input = second input) and the motor 29 is restarted. In the vacuum cleaner 1 of this embodiment, the rotating cleaning body 28 easily restarts against the rotational resistance with the carpet.

As described above, in the electric vacuum cleaner 1 according to this embodiment, when the input supplied to the electric motor 29 when the first contacted surface with a small rotational resistance is detected is the first input, and when the input supplied to the electric motor 29 when the second contacted surface with a larger rotational resistance is detected is the second input, the second input is controlled to be larger than the first input, and when starting the rotating cleaning body 28 in contact with the floor surface, the electric vacuum cleaner 1 temporarily starts the electric motor 29 with a third input larger than the first input. Therefore, the electric vacuum cleaner 1 can reliably start the electric motor 29 against the rotational resistance between the floor surface and the rotating cleaning body 28, and can achieve both dust removal performance and power saving that are suitable for the properties of the floor surface. Note that when the electric motor 29 starts, the rotating cleaning body 28 rotates in a direction that moves the suction port body 5 forward. And, by temporarily starting the electric motor 29 with a third input larger than the first input when the electric motor 29 starts, the electric vacuum cleaner 1 can assist the suction port body 5 in starting to move in a cleaning that is generally started by pushing the suction port body 5 forward.

In addition, when starting the rotating cleaning body 28 in contact with the floor surface, the vacuum cleaner 1 according to this embodiment starts the motor 29 temporarily with a third input equal to or greater than the second input. This allows the vacuum cleaner 1 to start the motor 29 more reliably against the rotational resistance between the floor surface and the rotating cleaning body 28, and also achieves both dust removal performance suited to the properties of the floor surface and power saving.

Furthermore, the vacuum cleaner 1 according to this embodiment starts the electric motor 29 when the rotating cleaning body 28 comes into contact with the floor surface. Therefore, the vacuum cleaner 1 can easily stop the electric motor 29 when the rotating cleaning body 28 leaves the floor surface, and can easily restart the electric motor 29 when the rotating cleaning body 28 comes into contact with the floor surface again.

In addition, the vacuum cleaner 1 according to this embodiment stops the motor 29 if the rotating cleaning body 28 leaves the floor surface while the motor 29 is rotating, and restarts the motor 29 with the input before it was stopped if the rotating cleaning body 28 touches the floor surface again within a predetermined first time, while restarting the motor 29 with a third input if the rotating cleaning body 28 touches the floor surface again after the first time. Therefore, the vacuum cleaner 1 can avoid frequent input switching in a situation where the suction mouth body 5 frequently leaves the floor surface or where the suction mouth body 5 is temporarily erroneously detected as having left the floor surface due to, for example, unevenness in the carpet.

Furthermore, the electric vacuum cleaner 1 according to this embodiment starts the electric motor 29 in response to at least one of the start of the electric blower 13 and the change in the operating output of the electric blower 13. Therefore, the electric vacuum cleaner 1 can easily restart the rotating cleaning body 28 in accordance with the user's intention to start cleaning with the electric vacuum cleaner 1.

In addition, the electric vacuum cleaner 1 according to this embodiment starts the electric motor 29 in response to a motor switch that receives an operation command for the rotating cleaning body 28. Therefore, the electric vacuum cleaner 1 can easily restart the rotating cleaning body 28 in accordance with the user's intention to start cleaning with the electric vacuum cleaner 1.

Furthermore, the electric vacuum cleaner 1 according to this embodiment distinguishes floor surfaces with different rotational resistances under a plurality of conditions and controls the magnitude of the input to the motor 29, while, within a predetermined second time period after the electric vacuum cleaner 1 leaves the floor surface and re-contacts the floor surface to start the electric motor 29 with a third input, the floor surface distinguishing condition is relaxed to distinguish floor surfaces with different rotational resistances. First, distinguishing floor surfaces with different rotational resistances under a plurality of conditions improves the accuracy of floor surface distinguishing. As in the electric vacuum cleaner 1 according to this embodiment, in the case where the first condition is whether or not a state in which the current value of the electric current flowing through the electric motor 29 is equal to or greater than a predetermined threshold value has continued for a certain period of time or more, and the second condition is whether or not the magnitude of the change in the electric current value flowing through the electric motor 29 from a time going back a predetermined floor surface estimation time to the present is equal to or greater than a predetermined second threshold value, the change over time in the second condition is monitored to avoid the first condition being suddenly satisfied and the floor surface being erroneously determined. On the other hand, if the motor 29 is started by the third input after it comes into contact with the floor surface again after leaving the floor surface, the floor surface discrimination conditions can be relaxed and limited to the first condition only, so that the type of floor surface after the motor 29 is quickly determined and the input of the motor 29 can be reduced, thereby improving power saving.

Therefore, with the electric vacuum cleaner 1 according to this embodiment, the motor 29 that generates the rotational drive of the rotating cleaning body 28 can be reliably started regardless of the rotational resistance between the floor surface and the rotating cleaning body 28.

Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

1... electric vacuum cleaner, 2... vacuum cleaner body, 3... extension tube, 5... suction port body, 11... handle, 12... body case, 12a... front part, 12b... center part, 12c... rear part, 13... electric blower, 15... dust separation and collection part, 16... suction pipe, 17... body control part, 18... secondary battery, 19... suction port, 21... control circuit board, 22... input part, 22a... operation start switch, 22b... operation stop switch, 25... exhaust port, 28... rotating cleaning body, 29... electric motor, 41... suction port body control part, 45... electric wire, 46... ground side electric wire, 47... non-ground side electric wire, 51... control power supply generation circuit, 52... reference voltage generation circuit, 53... drive circuit, 55... current detection circuit, 56... current limiting circuit, 57... switch, 58... safety device, 61... ground detection part.

Claims (6)

A rotating cleaning body that is rotatably supported;
an electric motor that generates a rotational driving force for the rotary cleaning body;
a detection unit that detects a physical quantity that can distinguish the magnitude of the rotational resistance of the rotary cleaning body relative to a contact surface with which the rotary cleaning body is in contact;
a control unit that controls the second input to be larger than the first input when an input supplied to the electric motor when a first contacted surface having a smaller rotational resistance is detected is defined as a first input, and when an input supplied to the electric motor when a second contacted surface having a larger rotational resistance than the first contacted surface is detected is defined as a second input,
When starting the rotating cleaning body that has come into contact with the contacted surface, the control unit temporarily starts the motor with a third input that is greater than the first input , and when the rotating cleaning body separates from the contacted surface while the motor is rotating, stops the motor, and when the rotating cleaning body comes back into contact with the contacted surface within a predetermined time, restarts the motor with the input before the motor was stopped, and when the rotating cleaning body comes back into contact with the contacted surface after the time has elapsed, restarts the motor with the third input . The vacuum cleaner of claim 1, wherein the third input is equal to or greater than the second input. a ground contact detection unit that detects when the rotary cleaning body comes into contact with the contact surface,
The electric vacuum cleaner according to claim 1 or 2, wherein the control unit starts the electric motor when the rotary cleaning body comes into contact with the contact surface. An electric blower that generates a negative pressure;
a switch for issuing a command to at least one of starting the electric blower and changing the operating output of the electric blower,
The electric vacuum cleaner according to claim 1 , wherein the control unit starts the electric motor with the third input when the switch is operated. a second switch for instructing at least one of starting the motor and changing the operating output of the motor;
The electric vacuum cleaner according to claim 1 , wherein the control unit starts the electric motor with the third input when the second switch is operated. The vacuum cleaner according to any one of claims 1 to 5, wherein the control unit distinguishes the contacted surfaces having different rotational resistances based on a plurality of conditions and controls the magnitude of the input to the motor, while relaxing the conditions to distinguish the contacted surfaces having different rotational resistances within a predetermined second time period after starting the motor with the third input.

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