CN110635671B

CN110635671B - Print head control circuit and printer

Info

Publication number: CN110635671B
Application number: CN201810646408.4A
Authority: CN
Inventors: 梅�明; 高选全; 陈艳
Original assignee: Senda Shenzhen Technology Co Ltd
Current assignee: Senda Shenzhen Technology Co Ltd
Priority date: 2018-06-21
Filing date: 2018-06-21
Publication date: 2025-05-13
Anticipated expiration: 2038-06-21
Also published as: CN110635671A

Abstract

The present invention discloses a nozzle control circuit and a printer, wherein the nozzle control circuit comprises: a nozzle power supply circuit and a power failure detection automatic discharge circuit; the nozzle power supply circuit supplies power to the nozzle and the power failure detection automatic discharge circuit; the power failure detection automatic discharge circuit receives a first reference voltage transmitted by the nozzle power supply circuit, and releases the electric energy of the high-voltage end of the nozzle according to the voltage change of the first reference voltage when the nozzle power supply circuit fails, so as to reduce the falling time of the voltage of the high-voltage end of the nozzle. The present invention has the advantages of low cost and can protect the nozzle from being damaged.

Description

Spray head control circuit and printer

Technical Field

The invention relates to the technical field of printing, in particular to a spray head control circuit and a printer.

Background

In the field of printers, power supply of a spray head is an important technology, the printer comprises the spray head and a spray head control circuit for controlling the spray head to supply power, the spray head control circuit supplies power for the high-voltage end of the spray head and the low-voltage end of the spray head respectively, the low-voltage end voltage of the spray head is required to rise before the high-voltage end voltage of the spray head in the power-on process when the spray head works, the low-voltage end voltage of the spray head is reduced after the high-voltage end voltage of the spray head is powered down, the circuit meets the normal use condition of the spray head, the spray head can be protected from being damaged, and the service life of the spray head is prolonged.

However, in the existing spray head control circuit at present, the high-voltage end and the low-voltage end of the spray head are directly connected with the power supply voltage, when the power supply is disconnected, the voltage on the high-voltage end and the low-voltage end of the spray head is directly reduced, the voltage on the low-voltage end of the spray head is reduced before the voltage on the high-voltage end of the spray head is reduced or the residual voltage on the high-voltage end of the spray head is still remained after the voltage on the low-voltage end of the spray head is reduced, the power-down state can not meet the power-down requirement of the spray head, the spray head is easy to damage, and the repair cost is expensive after the spray head is damaged, so how to solve the problem of power-down time sequence control of the spray head circuit is needed to be solved by those skilled in the art.

Disclosure of Invention

The invention solves the technical problem of providing a spray head control circuit which has low cost and can protect a spray head from being damaged when power is lost.

On one hand, the invention discloses a spray head control circuit which comprises a spray head power supply circuit and a power failure detection automatic discharge circuit, wherein the spray head power supply circuit supplies power to a spray head and the power failure detection automatic discharge circuit, and the power failure detection automatic discharge circuit receives a first reference voltage transmitted by the spray head power supply circuit and releases electric energy of a high-voltage end of the spray head according to voltage change of the first reference voltage when the spray head power supply circuit is powered down.

Preferably, the automatic discharging circuit for power failure detection comprises a reference voltage setting circuit, a switching circuit and a power failure discharging circuit, wherein the reference voltage setting circuit receives the first reference voltage transmitted by the spray head power supply circuit and outputs a reference voltage, the switching circuit receives the reference voltage transmitted by the reference voltage setting circuit and outputs a second reference voltage when the spray head power supply circuit is powered down, and the power failure discharging circuit receives the second reference voltage transmitted by the switching circuit and releases electric energy of a high voltage end of the spray head.

Preferably, the reference voltage setting circuit comprises a first capacitor, a first end of the first capacitor is electrically connected with the sprayer power supply circuit and the switch circuit, and a second end of the first capacitor is grounded.

Preferably, the reference voltage setting circuit further comprises a first resistor, a second resistor and a voltage stabilizing module, wherein the first end of the first resistor is electrically connected with the spray head power supply circuit, the second end of the first resistor is electrically connected with the first end of the second resistor, the first end of the second resistor is electrically connected with the third end of the voltage stabilizing module, the second end of the second resistor is grounded, the first end of the voltage stabilizing module is electrically connected with the spray head power supply circuit and the first end of the first capacitor, and the second end of the voltage stabilizing module is grounded.

Preferably, the switch circuit includes a first triode and a third resistor, an emitter of the first triode is electrically connected with a first end of the first capacitor, a base of the first triode is electrically connected with a first end of the third resistor, a collector of the first triode is electrically connected with the power-down discharge circuit, and a second end of the third resistor is electrically connected with a high-voltage end of the spray head.

Preferably, the power-down discharging circuit comprises a second triode, a first field effect tube and a fourth resistor, wherein a collector electrode of the second triode is electrically connected with the switching circuit, a base electrode of the second triode is electrically connected with a first end of the fourth resistor, an emitter electrode of the second triode is grounded, a grid electrode of the first field effect tube is electrically connected with the collector electrode of the second triode, a drain electrode of the first field effect tube is electrically connected with the high-voltage end of the spray head, a source electrode of the first field effect tube is electrically connected with the first end of the fourth resistor, and a second end of the fourth resistor is grounded.

Preferably, the sprayer power supply circuit includes an adjustable buck module that receives a supply voltage and outputs a third reference voltage to a low voltage end of the sprayer.

Preferably, the power supply circuit of the spray head further comprises a second field effect transistor, wherein a source electrode of the second field effect transistor receives the power supply voltage, and a drain electrode of the second field effect transistor outputs the first reference voltage to the automatic power-down discharge circuit for power-down detection.

Preferably, the power supply circuit of the spray head further comprises a third triode and a power failure detection module, wherein a base electrode of the third triode receives a power supply voltage, an emitter electrode of the third triode is grounded, and a collector electrode of the third triode outputs a first control voltage to the power failure detection module. The power failure detection module comprises an editable gate logic unit and a fourth triode, wherein the editable gate logic unit receives the first control voltage and outputs a second control voltage to the fourth triode, the base electrode of the fourth triode receives the second control voltage, the collector electrode of the fourth triode outputs a third control voltage to the grid electrode of the second field effect transistor, and the emitter electrode of the fourth triode is grounded.

On the other hand, the invention also discloses a printer which comprises a spray head and a spray head control circuit for controlling the spray head, wherein the spray head control circuit is any one of the spray head control circuits in the first aspect.

The spray head control circuit and the printer have the advantages that the printer comprises the spray head and the spray head control circuit, the spray head control circuit comprises the spray head power supply circuit and the automatic power-down discharging circuit for power-down detection, the spray head power supply circuit supplies power to the spray head in the power-up process of the printer and the automatic power-down discharging circuit for power-down detection, and the automatic power-down discharging circuit for power-down detection releases electric energy of the high-voltage end of the spray head in the power-down process of the spray head so as to reduce the time for reducing the voltage of the high-voltage end of the spray head and lead the voltage of the high-voltage end of the spray head to be reduced before the voltage of the low-voltage end of the spray head, so that the spray head can be protected from being damaged in the power-down process. In addition, the circuit has simple structure and low cost.

Drawings

FIG. 1 is a circuit diagram of a first embodiment of the present invention when a spray head control circuit is mated with a spray head;

fig. 2 is a circuit diagram of a second embodiment of the present invention when the spray head control circuit is mated with a spray head.

Detailed Description

The invention will now be described in detail with reference to the drawings and examples. It should be noted that, if not conflicting, the embodiments of the present invention and the features of the embodiments may be combined with each other, which are all within the protection scope of the present invention.

Example 1

Referring to fig. 1, the invention discloses a spray head control circuit for controlling a spray head to work, wherein the spray head comprises a high voltage end VH and a low voltage end VCC, the spray head control circuit comprises a spray head power supply circuit 1 and a power failure detection automatic discharge circuit 2, the spray head power supply circuit 1 supplies power to the spray head P and the power failure detection automatic discharge circuit 2, the power failure detection automatic discharge circuit 2 receives a first reference voltage transmitted by the spray head power supply circuit 1, and electric energy of the high voltage end VH of the spray head P is released according to voltage change of the first reference voltage when the spray head power supply circuit 1 is powered down, so that the falling time of the voltage of the high voltage end VH of the spray head P is reduced.

In this embodiment, the emitter of the third triode K1 is electrically connected with the low voltage end VCC through an eleventh resistor R11, the base of the third triode K1 is electrically connected with the power supply through a twelfth resistor R12, a thirteenth resistor R13 is connected between the base and the emitter of the third triode K1, and the thirteenth resistor R13 is used for pulling down the voltage of the third triode K1 to reduce interference and avoid the third triode K1 from being opened by mistake under the condition that the third triode K1 needs to be turned off.

The shower nozzle power supply circuit 1 still includes power failure detection module 11, power failure detection module 11 includes but the logical unit F of gate and fourth triode K2, but the collecting electrode of third triode K1 outputs first control voltage to gate logical unit F, but gate logical unit F receives first control voltage and output second control voltage to fourth triode K2, fourth triode K2's base receives the second control voltage, fourth triode K2's projecting pole ground, fourth triode K2's collecting electrode outputs third control voltage to second field effect transistor Q4's grid. In this embodiment, the Programmable gate logic unit F is an FPGA (Field-Programmable GATE ARRAY, i.e., a Field-Programmable gate array), and of course, the Programmable logic unit F may also be a CPLD (Complex Programmable Logic Device, i.e., a complex Programmable logic device) or the like. The programmable gate logic unit F is connected to the first port M, a second end of the programmable gate logic unit F is connected to the base of the fourth triode K2 through a fourteenth resistor R14, a collector of the fourth triode K2 is connected to the gate of the second field effect transistor Q4 through a seventeenth resistor R17, the base of the fourth triode K2 is electrically connected to a first end of a fifteenth resistor R15, a second end of the fifteenth resistor is grounded, and the fifteenth resistor R15 is used for pulling down the voltage of the fourth triode K2. It is understood that in one embodiment, the fourteenth resistor R14 and the seventeenth resistor R17 may not be required.

The sprayer power supply circuit 1 further comprises a second field effect transistor Q4, when the sprayer power supply circuit 1 is powered on, a source electrode of the second field effect transistor Q4 receives the power supply voltage VIN, and a drain electrode of the second field effect transistor Q4 outputs the first reference voltage to the automatic discharging circuit 2 for power failure detection and the high voltage end VH. In this embodiment, the second fet Q4 is turned on to provide the voltage for the automatic discharging circuit 2 for power failure detection when the power supply circuit 1 is powered on, and the second fet Q4 is turned off when the power supply circuit is powered off, at this time, the high voltage terminal VH supplies power to the power supply through the second fet Q4, in this embodiment, the type of the element adopted by the second fet Q4 is IRF9540, and it can be understood that the type of the element adopted by the second fet Q4 is not specifically limited herein.

The automatic discharging circuit 2 for power failure detection comprises a reference voltage setting circuit 21, a switch circuit 22 and a power failure discharging circuit 23, wherein the reference voltage setting circuit 21 receives the first reference voltage transmitted by the spray head power supply circuit 1 and outputs the reference voltage to the power failure discharging circuit 23, the reference voltage setting circuit 21 comprises a first capacitor C1, a first end of the first capacitor C1 is electrically connected with the spray head power supply circuit 1 and the switch circuit 22, and a second end of the first capacitor C1 is grounded. The first capacitor C1 receives the first reference voltage signal and charges when the power supply circuit 1 is powered on, and when the power supply circuit 1 is powered off, the first capacitor C1 starts to discharge and outputs the reference voltage.

The reference voltage setting circuit 21 further includes a first resistor R1, a second resistor R2, and a voltage stabilizing module L, where a first end of the first resistor R1 is electrically connected to the sprayer power supply circuit 1, a second end of the first resistor R1 is electrically connected to a first end of the second resistor R2, a first end of the second resistor R2 is electrically connected to a third end of the voltage stabilizing module L, a second end of the second resistor R2 is grounded, a first end of the voltage stabilizing module L is electrically connected to the sprayer power supply circuit 1 and a first end of the first capacitor C1, and a second end of the voltage stabilizing module L is grounded. The first resistor R1, the second resistor R2 and the voltage stabilizing module L are matched to control the reference voltage, and meanwhile, the output reference voltage is kept stable for a period of time, in this embodiment, a resistor exists between the first end of the first resistor R1 and the nozzle power supply circuit 1, the voltage stabilizing module L adopts a voltage stabilizer with a model of KIA431, it is understood that the voltage stabilizing module L can be replaced by other circuit elements, so long as the reference voltage is stabilized and controllable, and the specific limitation is not made herein.

The switch circuit 22 includes a first triode Q1 and a third resistor R3, where an emitter of the first triode Q1 is electrically connected to a first end of the first capacitor C1, a base of the first triode Q1 is electrically connected to a first end of the third resistor R3, a collector of the first triode Q1 is electrically connected to the power-down discharge circuit 23, and a second end of the third resistor R3 is electrically connected to the spray head P. The switch circuit 22 is used for controlling the power-down discharging circuit 23 to be turned on and off, the first triode Q1 is turned off when the power-up of the spray head power supply circuit 1 is performed, the power-down discharging circuit 23 does not work, the first triode Q1 is turned on when the power-down of the spray head power supply circuit 1 is performed, the power-down discharging circuit 23 starts to work, and the third resistor R3 is used for voltage division protection of the switch circuit 22.

The power-down discharging circuit 23 comprises a second triode Q2, a first field effect transistor Q3 and a fourth resistor R4, wherein a collector electrode of the second triode Q2 is electrically connected with the switch circuit 22, a base electrode of the second triode Q2 is electrically connected with a first end of the fourth resistor R4, an emitter electrode of the second triode Q2 is grounded, a grid electrode of the first field effect transistor Q3 is electrically connected with the collector electrode of the second triode Q2, a drain electrode of the first field effect transistor Q3 is electrically connected with the spray head power supply circuit 1, a source electrode of the first field effect transistor Q3 is electrically connected with a first end of the fourth resistor R4, and a second end of the fourth resistor R4 is grounded.

The power-down discharging circuit 23 discharges the high voltage terminal VH when the power supply circuit 1 is powered down, so as to accelerate the voltage drop speed of the high voltage terminal VH, after the gate of the first field effect transistor Q3 receives the second reference voltage, the first field effect transistor Q3 is turned on to discharge the high voltage terminal VH, and when the voltage of the high voltage terminal VH is greater than a preset value, the second triode Q2 is turned on, so that the current of the first field effect transistor Q3 can be prevented from being excessively large.

The working principle of the invention is that when the spray head power supply circuit 1 is powered on, the adjustable voltage reduction module N receives the power supply voltage VIN and outputs the power supply voltage VIN to the low voltage end VCC, the third triode K1 is turned on to output the first control voltage to the power failure detection module 11, the power failure detection module 11 receives the first control voltage and outputs the second control voltage to the fourth triode K2, the fourth triode K2 receives the second control voltage and outputs the third control voltage to the second field effect transistor Q4, the second field effect transistor Q4 is conducted to receive the power supply voltage VIN and outputs the first reference voltage to the reference voltage setting module, and the first capacitor C1 starts to charge.

When the power supply circuit 1 of the spray head is powered down, the third triode K1 outputs a first control voltage to the power-down detection module 11, the power-down detection module 11 receives the first control voltage and outputs a second control voltage to the fourth triode K2, the fourth triode K2 is closed, the second field effect transistor Q4 is closed, the first capacitor C1 outputs a reference voltage to the first triode Q1, the first triode Q1 receives the reference voltage and outputs a second reference voltage to the first field effect transistor Q3, so that the first field effect transistor Q3 is turned on, and the high voltage end VH discharges through the first field effect transistor Q3. Therefore, when the power-on of the sprayer power supply circuit 1 is performed, the voltage of the low-voltage end VCC is established before the voltage of the high-voltage end VH, and when the power-off of the sprayer power supply circuit 1 is performed, the voltage of the low-voltage end VCC is reduced after the voltage of the high-voltage end VH, so that the protection of the sprayer P from damage in the use process can be realized, and the circuit is low in cost and convenient to popularize and use.

As can be seen from the above, since the spray head control circuit of the present invention includes the spray head power supply circuit 1 and the power-down detection automatic discharge circuit 2, the spray head power supply circuit 1 supplies power to the spray head and the power-down detection automatic discharge circuit 2 during the power-up process of the printer, and the power-down detection automatic power-down discharge circuit 2 releases the power of the high voltage terminal VH of the spray head during the power-down process of the spray head P, so as to reduce the voltage drop time of the high voltage terminal VH of the spray head P, and make the voltage of the high voltage terminal VH of the spray head drop before the voltage of the low voltage terminal VCC of the spray head, thereby protecting the spray head from being damaged during the power-down process. In addition, the circuit has simple structure and low cost.

Example two

Referring to fig. 2, the present embodiment is similar to the first embodiment in structure, and is mainly different in that the spray head control circuit further includes a first filter capacitor C2, a second filter capacitor C3, and a sixteenth resistor R16, and the power failure detection circuit includes a diode D, an eighteenth resistor R18, a nineteenth resistor R19, and a twentieth resistor R20.

The first end of the first filter capacitor C2 is electrically connected with the power supply and the adjustable voltage reduction module N, the second end of the first filter capacitor C2 is grounded, the first end of the second filter capacitor C3 is electrically connected with the drain electrode of the second field effect transistor Q4 and the high voltage end VH, and the second end of the second filter capacitor C3 is grounded. The first filter capacitor C2 is configured to filter the power supply voltage VIN received by the adjustable buck module N, and the second filter capacitor C3 is configured to filter the first reference voltage received by the high voltage terminal VH.

The first end of the sixteenth resistor R16 is electrically connected to the source electrode of the second field effect transistor Q4, the second end of the sixteenth resistor R16 is electrically connected to the gate electrode of the second field effect transistor Q4, and the sixteenth resistor R16 is used for pulling down the voltage and reducing the interference.

The anode of the diode D is electrically connected with the drain electrode of the second field effect transistor Q4, and the cathode of the diode D is electrically connected with the first end of the first resistor R1, the first end of the voltage stabilizing module L and the first end of the first capacitor C1; in this embodiment, when the shower head control circuit is powered on, the first capacitor C1 receives the first reference voltage through the diode D to start charging, when the shower head control circuit is powered off, the first capacitor C1 starts discharging, the diode D is turned on unidirectionally, and the switch circuit 22 receives the reference voltage.

The first end of the eighteenth resistor R18 is electrically connected with the collector of the first triode Q1, the second end of the eighteenth resistor R18 is electrically connected with the collector of the second triode Q2 and the gate of the first field effect transistor Q3, the first end of the nineteenth resistor R19 is electrically connected with the second end of the fourth resistor R4 and the source of the first field effect transistor Q3, the second end of the nineteenth resistor R19 is electrically connected with the emitter of the second triode Q2, the first end of the twentieth resistor R20 is electrically connected with the collector of the second triode Q2, and the second end of the twentieth resistor R20 is electrically connected with the emitter of the second triode Q2. The current value of the discharge of the first field effect transistor Q3 can be set by setting the resistance values of the fourth resistor R4 and the nineteenth resistor R19, so as to precisely control the voltage of the high voltage terminal VH.

Example III

The invention also discloses a printer, which comprises a nozzle and a nozzle control circuit for controlling the nozzle, wherein the nozzle control circuit can be the nozzle control circuit in the first embodiment or the second embodiment, and the detailed description is referred to the first embodiment and the second embodiment and is not repeated here. In this embodiment, the structure of the head control circuit of this embodiment is the same as that of the head control circuit of the first embodiment, and thus the same technical effects are achieved.

While the invention has been described in detail in terms of the nozzle control circuit and printer provided herein, specific examples are provided herein to illustrate the principles and embodiments of the invention, the above examples are provided to assist in understanding the method and core ideas thereof, and modifications in terms of specific embodiments and application scope are intended to be included in the scope of the invention as defined by the following claims. And should not be construed as limiting the invention.

Claims

1. A nozzle control circuit, characterized in that it comprises: a nozzle power supply circuit and a power-off detection automatic discharge circuit; the nozzle power supply circuit supplies power to the nozzle and the power-off detection automatic discharge circuit; the power-off detection automatic discharge circuit receives a first reference voltage transmitted from the nozzle power supply circuit, and releases the electric energy at the high-voltage end of the nozzle according to the voltage change of the first reference voltage when the nozzle power supply circuit is powered off; the power-off detection automatic discharge circuit comprises a reference voltage setting circuit, a switch circuit and a power-off discharge circuit, the reference voltage setting circuit receives the first reference voltage transmitted from the nozzle power supply circuit and outputs a reference voltage, the switch circuit is connected The reference voltage setting circuit receives the reference voltage transmitted by the reference voltage setting circuit and outputs a second reference voltage when the power supply circuit of the nozzle is powered off, and the power-off discharge circuit receives the second reference voltage transmitted by the switch circuit and releases the electric energy at the high-voltage end of the nozzle; the reference voltage setting circuit also includes a first capacitor, a first resistor, a second resistor and a voltage stabilizing module, the first end of the first resistor is electrically connected to the power supply circuit of the nozzle, the second end of the first resistor is electrically connected to the first end of the second resistor, the first end of the second resistor is electrically connected to the third end of the voltage stabilizing module, and the second end of the second resistor is grounded; the first end of the voltage stabilizing module is electrically connected to the nozzle power supply circuit .... The first end of the first capacitor is electrically connected to the power circuit, and the second end of the voltage stabilizing module is grounded; the switching circuit includes a first transistor and a third resistor, the emitter of the first transistor is electrically connected to the first end of the first capacitor, the base of the first transistor is electrically connected to the first end of the third resistor, the collector of the first transistor is electrically connected to the power-off discharge circuit, and the second end of the third resistor is electrically connected to the high-voltage end of the nozzle; the power-off discharge circuit includes a second transistor, a first field effect transistor and a fourth resistor, the collector of the second transistor is electrically connected to the switching circuit, and the base of the second transistor is electrically connected to the first end of the fourth resistor; The emitter of the second triode is grounded, the gate of the first field effect tube is electrically connected to the collector of the second triode, the drain of the first field effect tube is electrically connected to the high voltage end of the nozzle, and the source of the first field effect tube is electrically connected to the first end of the fourth resistor; the second end of the fourth resistor is grounded; the nozzle power supply circuit includes an adjustable step-down module, which receives the power supply voltage and outputs a third reference voltage to the low voltage end of the nozzle; the nozzle power supply circuit also includes a second field effect tube, the source of the second field effect tube receives the power supply voltage, and the drain of the second field effect tube outputs the first reference voltage to the power-off detection automatic discharge circuit;

The nozzle control circuit also includes a first filter capacitor, a second filter capacitor and a sixteenth resistor; the first end of the first filter capacitor is electrically connected to the power supply and the adjustable step-down module, and the second end of the first filter capacitor is grounded; the first end of the second filter capacitor is electrically connected to the drain of the second field effect transistor and the high voltage end, and the second end of the second filter capacitor is grounded; the first end of the sixteenth resistor is electrically connected to the source of the second field effect transistor, and the second end of the sixteenth resistor is electrically connected to the gate of the second field effect transistor.

2 . The nozzle control circuit according to claim 1 , wherein a first end of the first capacitor is electrically connected to the nozzle power supply circuit and the switch circuit, and a second end of the first capacitor is grounded.

3. The nozzle control circuit according to claim 1 is characterized in that the nozzle power supply circuit also includes a third transistor and a power-off detection module, the base of the third transistor receives the power supply voltage, the emitter of the third transistor is grounded, and the collector of the third transistor outputs a first control voltage to the power-off detection module; the power-off detection module includes an editable gate logic unit and a fourth transistor, the editable gate logic unit receives the first control voltage and outputs a second control voltage to the fourth transistor, the base of the fourth transistor receives the second control voltage, the collector of the fourth transistor outputs the third control voltage to the gate of the second field effect transistor, and the emitter of the fourth transistor is grounded.

4. A printer, comprising a nozzle and a nozzle control circuit for controlling the nozzle, wherein the nozzle control circuit is the nozzle control circuit according to any one of claims 1 to 3.