CN110063670B - A motor safety circuit and mixer - Google Patents

Abstract

The embodiment of the invention relates to the technical field of control circuits, and particularly discloses a motor safety circuit and a stirrer, wherein the motor safety circuit comprises a first resistance-capacitance voltage reduction circuit, a motor control circuit, a blocking circuit and a second resistance-capacitance voltage reduction circuit which are connected with each other; the first resistance-capacitance voltage reduction circuit comprises a first voltage stabilizing diode, the second resistance-capacitance voltage reduction circuit comprises a second voltage stabilizing diode, the motor control circuit comprises a switch circuit, a controller and a charging circuit, and the controller is respectively connected with the blocking circuit, the switch circuit and the charging circuit; the charging circuit is connected with the switch circuit, and the second resistance-capacitance voltage reduction circuit is connected with the charging circuit; when the switching circuit is in a disconnected state, the motor is in a non-working state, the first voltage stabilizing diode is connected with the charging circuit in parallel, and the controller controls the on-off of the blocking circuit by outputting a square wave signal. By the mode, the power consumption of the household appliance in the standby state can be reduced.

Description

A motor safety circuit and mixer

technical field

Embodiments of the present invention relate to the technical field of control circuits, and in particular, to a motor safety circuit and a mixer.

Background technique

The common mixer in kitchen appliances, its working principle is to drive the sharp cutter head to rotate through the AC electric motor safety circuit, thereby cutting or crushing food, so the mixer has high safety requirements in small household appliances.

During the process of implementing the present invention, the inventor of the present invention found that due to circuit design and other reasons in the existing mixer, during use, the power consumption in the standby state is relatively large.

SUMMARY OF THE INVENTION

In view of the above-mentioned defects of the prior art, the main purpose of the embodiments of the present invention is to provide a motor safety circuit and a mixer, so as to reduce the power consumption of household appliances in a standby state.

In order to solve the above technical problem, a technical solution adopted in the embodiment of the present invention is to provide a motor safety circuit, which includes: a first resistance-capacitance step-down circuit, a motor control circuit and a blocking circuit connected to each other; Capacitance and step-down circuit, the second resistance-capacitance step-down circuit is connected to the motor control circuit; the motor control circuit is used to control the start and stop of the motor; the first resistance-capacitance step-down circuit includes a first Zener diode, so The motor control circuit includes a switch circuit, a controller and a charging circuit, the controller is respectively connected with the blocking circuit, the switch circuit and the charging circuit; the charging circuit is connected with the switch circuit; the The first Zener diode is connected to the charging circuit; when the switch circuit is in an off state, the motor is in a non-working state, the first Zener diode charges the charging circuit, and the control The device controls the on-off of the blocking circuit by outputting a square wave signal; when the blocking circuit is connected, the first Zener diode is short-circuited; the second resistance-capacitance step-down circuit includes a second Zener diode , the Zener diode is connected to the charging circuit; when the switch circuit is in an on state, the motor is in a working state, and the second resistance-capacitance step-down circuit charges the charging circuit, and the charging circuit The switch circuit is powered.

Optionally, the motor safety circuit further includes a bidirectional thyristor, the bidirectional thyristor is connected to the controller, the bidirectional thyristor is connected in series with the motor, and is used to control the start and stop of the motor.

Optionally, the switch circuit includes a control switch, a relay and a first switch assembly, the control switch is connected to one end of the charging circuit; the first end of the relay is connected to one end of the power supply, and the first end of the relay is connected to one end of the power supply. The two ends are connected to the motor and one end of the second resistance-capacitance step-down circuit, and the other end of the motor and the second resistance-capacitance step-down circuit is connected to the other end of the power supply, wherein the first end of the relay One end and the second end are two ends of the switch of the relay; the third end of the relay is connected to the control switch, and the fourth end of the relay is connected to the first end of the first switch assembly, The control end of the first switch assembly is connected to the controller, the second end of the first switch assembly is connected to the charging circuit, wherein the third end and the fourth end of the relay are the relay When the control switch is turned on, the third end of the relay is connected to the charging circuit, and the charging circuit supplies power to the coil of the relay.

Optionally, the charging circuit includes a first charging capacitor, the first charging capacitor is connected in parallel with the second resistance-capacitance step-down circuit, and when the control switch is turned off, the first charging capacitor is connected to the second charging capacitor in parallel. A Zener diode is connected in parallel; when the control switch is turned on, the first charging capacitor and the coil of the relay are connected in parallel.

Optionally, the charging circuit further includes a second charging capacitor, the first resistance-capacitance step-down circuit further includes a third Zener diode, the third Zener diode is connected in series with the first Zener diode, so The third Zener diode is connected in parallel with the second charging capacitor, and both ends of the second charging capacitor are respectively connected to two power ports of the controller.

Optionally, the blocking circuit includes a second switch assembly, and the controller includes a third output end; the control end of the second switch assembly is connected to the third output end; the second switch assembly is connected to The first Zener diodes are connected in parallel; when the control switch is turned off, the third output terminal outputs a square wave with alternating high and low levels.

Optionally, the blocking circuit further includes a third switch assembly; the third output end is connected to the control end of the third switch assembly; the first end of the third switch assembly is connected to the second switch The control end of the assembly is connected, and the second end of the third switch assembly is grounded.

Optionally, the first resistance-capacitance step-down circuit further includes a first step-down resistor, a first step-down capacitor, a first forward diode and a first reverse diode; one end of the first step-down capacitor is connected to the first step-down capacitor. The first step-down resistor is connected, the other end of the first step-down capacitor is connected to the first forward diode and one end of the first reverse diode respectively; the other end of the first reverse diode is connected to One end of the first zener diode is connected; when the control switch is turned off, the first zener diode is connected to the charging circuit; the other end of the first step-down resistor is connected to one end of the power supply, the The first forward diode and the other end of the first Zener diode are connected to the other end of the power supply; the second resistance-capacitance step-down circuit also includes a second step-down resistor, a second step-down capacitor, a second forward voltage diode and a second reverse diode; two ends of the second step-down resistor are respectively connected to the second end of the relay and one end of the second step-down capacitor, and the other end of the second step-down capacitor is respectively is connected with one end of the second forward diode and the second reverse diode; the other end of the second reverse diode is connected with one end of the second Zener diode; the second Zener diode is connected to The charging circuits are connected in parallel; the other ends of the second forward diode and the second Zener diode are connected to the other end of the power supply.

Optionally, the first resistance-capacitance step-down circuit further includes an auxiliary charging capacitor, and the auxiliary charging capacitor is connected in parallel with the first Zener diode.

In order to solve the above technical problem, an embodiment of the present invention also provides a mixer, which includes the above-mentioned motor safety circuit.

The beneficial effect of the embodiment of the present invention is: different from the situation in the prior art, in the embodiment of the present invention, when the switch circuit is turned on, the controller receives the switch circuit turn-on information, so that the switch circuit is charged by the charging circuit. In addition, when the switch circuit is charged by the charging circuit, the motor and the second resistance-capacitance step-down circuit are both connected to the power supply. At this time, the motor is turned on and in a working state, and the charging circuit starts to be powered by the second resistance-capacitance step-down circuit. When the switch circuit is turned off, the charging circuit is charged by the first Zener diode in the first resistance-capacitance step-down circuit. At this time, the controller outputs square waves with alternating high and low levels to the blocking circuit. When the blocking circuit is connected, the first Zener diode is short-circuited, so that it is not supplied with power, thereby reducing standby power consumption. Further, in this embodiment of the present invention, the time interval for restoring the power supply of the first Zener diode can be controlled by adjusting the duty ratio of the square wave output by the controller with alternating high and low levels, so that power consumption can be controlled.

The above description is only an overview of the technical solutions of the present invention, in order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand , the following specific examples of the present invention are given.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are for purposes of illustrating preferred embodiments only and are not to be considered limiting of the invention. Also, the same components are denoted by the same reference numerals throughout the drawings. In the attached image:

1 is a structural block diagram of a motor safety circuit according to an embodiment of the present invention;

FIG. 2 is a circuit schematic diagram of a motor safety circuit according to an embodiment of the present invention.

Detailed ways

Embodiments of the technical solutions of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only used to more clearly illustrate the technical solutions of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

It should be noted that, unless otherwise specified, the technical or scientific terms used in this application should have the usual meanings understood by those skilled in the art to which the present invention belongs.

In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. In the description of the present invention, "plurality" means two or more, unless otherwise expressly and specifically defined.

Please refer to FIG. 1 , the motor safety circuit 100 includes a motor control circuit 200 , a first RC step-down circuit 300 , a second RC step-down circuit 400 and a blocking circuit 500 . Wherein, the motor control circuit 200 , the first resistance-capacitance step-down circuit 300 and the blocking circuit 500 are connected to each other, and the motor control circuit 200 is used to control the start and stop of the motor 20 . In addition, the first RC step-down circuit 300 includes a first Zener diode 305 , the second RC step-down circuit 400 includes a second Zener diode 405 , and the motor control circuit 200 includes a switch circuit 210 , a controller 230 and a charger In the circuit 220 , the controller 230 is respectively connected with the blocking circuit 500 , the switch circuit 210 and the charging circuit 220 , the charging circuit 220 is connected with the switching circuit 210 , and the second Zener diode 405 is connected with the charging circuit 220 .

When the switch circuit 210 is in an off state, the switch circuit 210 disconnects the motor 20 and the second resistance-capacitance step-down circuit 400 from the power source. At this time, the motor 20 is in a non-working state, and the first Zener diode 305 is connected in parallel with the charging circuit 220 for charging the charging circuit 220 . Meanwhile, the controller 230 controls the on-off of the blocking circuit 500 by outputting a square wave signal. In one embodiment, when the blocking circuit 500 receives a low level, the blocking circuit 500 is connected. When the blocking circuit 500 is connected, the blocking circuit 500 can control the first Zener diode 305 to short-circuit, so that the first Zener diode 305 is not powered, thereby reducing power consumption.

When the switch circuit 210 is in the on state, the motor 20 and the second resistance-capacitance step-down circuit 400 are connected to the power supply 10. At this time, the motor 20 is in a working state, and the second resistance-capacitance step-down circuit 400 charges the charging circuit 220, and the charging circuit 200 supplies power to switching circuit 210 .

In the embodiment of the present invention, when the motor 20 is in a non-working state, the controller 230 outputs a square wave with alternating high and low levels to the blocking circuit 500, so that the first Zener diode 305 is intermittently powered, thereby reducing power consumption. Further, in this embodiment of the present invention, the time interval for restoring the power supply of the first Zener diode 305 can be controlled by adjusting the duty ratio of the square wave output by the controller 230 with alternating high and low levels, so as to control how much power consumption is reduced.

When the switch circuit 210 is in an off state, the charging circuit 200 is connected in parallel with the first Zener diode 305 , and the first Zener diode 305 charges the charging circuit 200 . At the same time, the connection between the switch circuit 210 and the charging circuit 200 is disconnected. When the switch circuit 210 is in an off state, the switch circuit 210 will disconnect the motor 20 from the power source 10 , so that the motor 20 is in a non-working state.

When the switch circuit 210 is in the on state, the charging circuit 200 is disconnected from the first voltage regulator diode 305, the switch circuit 210 and the charging circuit 200 are connected and closed, and the charging circuit 200 provides power to the switching circuit 210. When power is supplied, the switch circuit 210 connects the second resistance-capacitance step-down circuit 400, the motor 20 and the power supply 10, so that the motor 20 is in a working state, and at the same time, the second Zener diode 405 of the second resistance-capacitance step-down circuit 400 can be connected to the power supply. The charging circuit 200 charges.

When the switch circuit 210 is turned on and the power source 10 is cut off, the motor 20 stops running, the charging circuit 200 also loses power supply, and the switch circuit 210 also loses power supply, so that the second resistance-capacitance step-down circuit 400 is disconnected from the power source 10 . After that, when the power supply 10 is reconnected, the charging circuit 200 has neither the first Zener diode 305 nor the second Zener diode 405 to supply power, so the motor 20 cannot work again. The switch circuit 210 needs to be turned back to the off state first, the charging circuit 200 is powered first, and then the switch circuit 210 is turned back on, so that the motor 20 can work again. In the above manner, the embodiment of the present invention realizes that when the motor 20 is reconnected after power interruption, it will not continue to work, thereby avoiding potential safety hazards for users and realizing the function of a safety protection circuit.

In some embodiments, a triac 600 may also be added to the circuits of the above-mentioned embodiments. Specifically, referring to FIG. 2 , the control end of the triac 600 is connected to the controller 230 , and the triac 600 is connected in series with the motor 20 to control the start and stop of the motor 20 . When the switch circuit 200 is turned on, the controller 230 receives the information that the switch circuit 200 is turned on, and then outputs information to the triac 600 to close the triac 600 , so that the motor 20 is connected to the power supply 10 . On the contrary, when the switch circuit 200 is turned off, the controller 230 controls the triac 600 to be disconnected, so that the motor 20 is disconnected from the power source 10 . In the above manner, the control of the start and stop of the motor 20 by the triac 600 can be realized.

In this embodiment, the triac 600 is added to the solution of the previous embodiment, so that the user can adjust the distance between the two thyristors in the triac 600 through the controller 230, thereby changing the current flowing through the motor 20, and achieving the purpose of changing the rotational speed of the motor 20. In addition, the triac 600 also improves the safety of the circuit. When the switch circuit 210 fails, the motor 20 can still be turned off through the triac 600 .

For the above-mentioned controller 230 , referring to FIG. 2 , the controller 230 includes an input terminal 231 , a first output terminal 232 , a second output terminal 233 and a third output terminal 234 . The input terminal 231 is connected to the charging circuit 220 , and the on and off states of the switch circuit 210 are determined by detecting the voltage information of the charging circuit 220 . The first output terminal 232 is connected to the switch circuit 210 . The second output terminal 233 is connected to the control terminal of the triac 600 to control the opening and closing of the triac 600 according to the working state of the motor control circuit 200 . The triac 600 is also used for connecting with the motor 20 to control the disconnection and connection between the motor 20 and the power supply 10 , and can also control the magnitude of the current passing through the motor 20 to adjust the working state of the motor 20 . The third output terminal 234 is connected to the blocking circuit 500 , and the third output terminal 234 can output a square wave with alternating high and low levels to control the connection and disconnection of the blocking circuit 500 according to the working state of the motor control circuit 200 .

For the above-mentioned switch circuit 210 and charging circuit 220 , referring to FIG. 2 , the switch circuit 210 includes a control switch 211 , a relay 212 and a first switch component 213 . The charging circuit 220 includes a first charging capacitor 221, a third discharging resistor 222 and a second charging capacitor 223'. The control switch 211 can be a single-pole double-throw switch, the fixed end of which is connected to one end of the first charging capacitor 221 . The active end of the control switch 211 may have a closed end (end A in FIG. 2 ) and an open end (end B in FIG. 2 ), which respectively indicate the closing and opening of the control switch 211 , and the closing and opening of the control switch 211 . On means the switch circuit 210 is turned off and on. The close end is connected to the first Zener diode 305 in the first resistance-capacity step-down circuit 300 , the open end is connected to the third end of the relay 212 , and the fourth end of the relay 212 is connected to the first switch component 213 The first end of the first switch assembly 213 is connected to the controller 230, the second end of the first switch assembly 213 is connected to the charging circuit 220, and the third end and the fourth end of the relay 212 The terminals are both ends of the coil of the relay 212 . The first end of the relay 212 is connected to one end of the power supply 10 , the second end of the relay 212 is connected to the motor 20 and one end of the second resistance-capacitance step-down circuit 400 , and the other end of the motor 20 and the second resistance-capacitance step-down circuit 400 is connected. One end is connected to the other end of the power supply 10 , wherein the first end and the second end of the relay 212 are two ends of the switch of the relay 212 .

The other end of the first charging capacitor 221 is respectively connected to one end of the second charging capacitor 223, and the second charging capacitor 223 and the first charging capacitor 221 connected in series are also connected in parallel to the second resistance-capacitor step-down circuit 400 and the series-connected second charging capacitor 223. The first switch assembly 213 and the coil of the relay 212 are used to supply power to the coil of the relay 500 . The other end of the second charging capacitor 223 is connected to the input end 231 of the controller 230 , and both ends of the second charging capacitor 223 are respectively connected to two power ports of the controller 230 for supplying the controller 230 powered by. The third pressure relief resistor 222 is connected in parallel with the first charging capacitor 221, and is used to rapidly discharge the first charging capacitor 221 when the power is turned off, so as to prevent the first charging capacitor 221 from still in There is residual power.

When the control switch 211 is turned off, that is, when the active end of the control switch 211 is at the B end, the first charging capacitor 221 and the second charging capacitor 223 connected in series are connected in parallel to the first resistance-capacitor step-down circuit 300, and the first charging capacitor 221 and the second charging capacitor 223 are connected in parallel to The resistance-capacitance step-down circuit 300 is charged to store electricity. At this time, the controller 230 is powered by the second charging capacitor 223 and starts to operate. The controller 230 obtains the signal that the control switch 211 is turned off through the voltage received by its input terminal 231, and then the controller 230 controls the first switch assembly 213 to turn off through the control terminal of the first switch assembly 213, so that the first charging capacitor 221 and the The second charging capacitor 223 cannot supply power to the coil of the relay 212 , so that the controller 230 controls the switch circuit 210 to disconnect from the charging circuit 200 . Therefore, the switch of the relay 212 is in an off state, so that the connection between the motor 20 and the power source 10 is disconnected, so that the power cannot be supplied, and the operation is stopped.

When the motor 20 needs to be started, the active end of the control switch 211 can be adjusted to the open end. At this time, the voltage received by the input terminal 231 of the controller 230 changes, the controller 230 obtains the signal that the control switch 211 is turned on, and then the controller 230 controls the first switch component 213 to conduct, so that the coil of the relay 212 is connected to the first switch 213. The charging capacitor 221 and the second charging capacitor 223 form a loop, so that the controller 230 controls the switch circuit 210 to communicate with the charging circuit 200 . The electricity stored by the first charging capacitor 221 and the second charging capacitor 223 when the control switch 211 is turned off can supply power to the coil of the relay 212, so that the switch of the relay 212 is turned on. After that, the motor 20 can be connected to the power source 10 and start running. At the same time, the second RC step-down circuit 400 is also connected to the power supply 10, and the second RC step-down circuit 400 starts to supply power to the first charging capacitor 221 and the second charging capacitor 223 to ensure that the switch of the relay 212 is continuously turned on. In the above manner, when the control switch 211 is turned off, the motor 20 stops running, and when the control switch 211 is turned on, the motor 20 continues to run.

When the control switch 211 is turned on and the power supply 10 is cut off, the motor 20 stops running, and the first charging capacitor 221 and the second charging capacitor 223 lose power supply at the same time. When the power of the first charging capacitor 221 and the second charging capacitor 223 is exhausted, the switch of the relay 212 is turned off. When the power supply 10 is reconnected, the power of the first charging capacitor 221 and the second charging capacitor 223 has been exhausted, so that the switch of the relay 212 is turned off, so the second resistance-capacitance step-down circuit 400 cannot be connected to the power supply 10, so The first charging capacitor 221 and the second charging capacitor 223 cannot be charged. Therefore, the first charging capacitor 221 and the second charging capacitor 223 cannot supply power to the coil of the relay 212 , so that the switch of the relay 212 is continuously turned off, and the motor 20 cannot be connected to the power supply 10 . The motor 20 can only be restarted by adjusting the active end of the control switch 211 to the off end, charging the first charging capacitor 221 and the second charging capacitor 223 first, and then adjusting the active end of the control switch 211 to the on end. In the above manner, the motor 20 will not continue to run when the power is turned off and the power is turned on again, thereby avoiding the safety hazard caused thereby.

It can be understood that: the control switch 211 is not limited to the above description, and can also be other devices with the same control effect, which will not be repeated here. In addition, in other embodiments, the third bleeder resistor 222 and/or the second charging capacitor 223 in the charging circuit 220 can be omitted, the coil of the relay 212 is only powered by the first charging capacitor 221, and the controller 230 also Can be powered by a separate power supply. The switch circuit 210 and the charging circuit 220 are not limited to the above description, and may also be other circuits with the same switching or charging effect, which will not be described here.

For the above-mentioned first switch assembly 213, the first switch assembly 213 can be selected from a triode. The base of the triode is the control terminal of the first switch component 213 . When the first output terminal 232 of the controller 230 outputs a high level or a low level to the base of the triode, the short circuit or open circuit of the collector and the emitter of the triode can be controlled, thereby realizing the switching of the first switch component 213 . Of course, in other embodiments, the first switch component 213 may also be other devices having the same switching effect, and details are not described herein again.

For the above-mentioned first RC step-down circuit 300, referring to FIG. 2, the first RC step-down circuit 300 further includes a first step-down resistor 301, a first step-down capacitor 302, a first forward diode 303, a A reverse diode 304 , a third Zener diode 306 , a first bleeder resistor 307 , an auxiliary charging capacitor 308 and an anti-discharge diode 309 . Two ends of the first step-down resistor 301 are respectively connected to the other end of the power source 10 and one end of the first step-down capacitor 302 . The other ends of the first step-down capacitor 302 are respectively connected to one ends of the first forward diode 303 and the first reverse diode 304 . The other end of the first reverse diode 304 is connected to one end of the first Zener diode 305, the other end of the first Zener diode 305 is connected to one end of the third Zener diode 306, and the first Zener diode 305 is also The blocking circuit 500 is connected in parallel. The blocking circuit 500 can intermittently short-circuit the first Zener diode 305 through the square wave with alternating high and low levels output by the third output terminal 234 of the controller 230, thereby achieving the purpose of reducing standby power consumption. The other ends of the third Zener diode 306 and the first forward diode 303 are connected to one end of the power supply 10 , so that the first resistance-capacitance step-down circuit 300 is connected to the power supply 10 . In addition, when the control switch 211 is turned off, the first Zener diode 305 and the third Zener diode 306 are respectively connected in parallel with the first charging capacitor 221 and the second charging capacitor 223 to charge them.

Wherein, the power supply 10 outputs alternating current, and the voltage is stepped down through the first step-down resistor 301 and the first step-down capacitor 302 . Afterwards, the forward current in the alternating current is blocked by the first reverse diode 304, and a fluctuating direct current is formed to flow through the first Zener diode 305 and the third Zener diode 306, and the first Zener diode 305 and the third Zener diode 305 and the third Zener diode 306. The Zener diode 306 converts the fluctuating DC power into a stable DC power to stably charge the first charging capacitor 221 and the second charging capacitor 223 . In addition, the blocked forward current can also flow back to the power supply 10 through the first forward diode 303, so that the first step-down capacitor 302 can be smoothly charged and discharged.

In the above manner, the embodiment of the present invention can step-down and stabilize the AC power output by the power supply 10, and finally form a stable low-voltage DC power to supply power to the first charging capacitor 221 and the second charging capacitor 223, thereby preventing the first charging capacitor 221 and the second charging capacitor 223. The second charging capacitor 223 is burned out by the high voltage, which plays a protective role.

For the above-mentioned first pressure relief resistor 307, the first pressure relief resistor 307 is connected in parallel with the first step-down capacitor 302, so that when the power supply 10 is disconnected, the first step-down capacitor 302 can quickly drain power.

For the above-mentioned auxiliary charging capacitor 308 , the auxiliary charging capacitor 308 is also connected in parallel with the first Zener diode 305 , so that it can be charged through the first Zener diode 305 . When the first charging capacitor 221 is connected in parallel with the first Zener diode 305, the fully charged auxiliary charging capacitor 308 can simultaneously charge the first charging capacitor 221 to achieve the effect of fast charging.

For the above-mentioned anti-discharge diode 309 , the anti-discharge diode 309 is connected in series between the auxiliary charging capacitor 308 and the first Zener diode 305 . It can prevent that the power of the auxiliary charging capacitor 308 is also consumed when the first Zener diode 305 is short-circuited by the blocking circuit 500, so that the first charging capacitor 221 cannot be charged.

It can be understood that in other embodiments, the first bleeder resistor 307 and/or the auxiliary charging capacitor 308 and/or the anti-discharge diode 309 can also be omitted, and the first charging capacitor 221 can be charged only by the first Zener diode 305 For the controller circuit without the second charging capacitor 223, the third Zener diode 306 can also be omitted. In addition, the first resistance-capacitance step-down circuit 300 is not limited to the above description, and may also be other circuits having the same step-down and voltage-stabilizing effects, which will not be repeated here.

For the second RC step-down circuit 400, referring to FIG. 2, the second RC step-down circuit 400 further includes a second step-down resistor 401, a second step-down capacitor 402, a second forward diode 403, a Two reverse diodes 404 , a second bleeder resistor 406 , a first protection resistor 407 and a third reverse diode 408 . Two ends of the second step-down resistor 401 are respectively connected to one end of the switch of the relay 212 and one end of the second step-down capacitor 402 , and the other end of the switch of the relay 212 is used to connect the other end of the power supply 10 . The other ends of the second step-down capacitor 402 are respectively connected to one ends of the second forward diode 403 and the second reverse diode 404 . The other end of the second reverse diode 404 is connected to one end of the second Zener diode 405, and the second Zener diode 405 is connected in parallel with the first charging capacitor 221 and the second charging capacitor 223 in series. The other end of the switch of the relay 212 is used to connect to the other end of the power supply 10 , and the other ends of the second forward diode 403 and the second Zener diode 405 are used to connect to one end of the power supply 10 .

When the switch of the relay 212 is closed, the power supply 10 is connected to the second resistance-capacitance step-down circuit 400 . The alternating current output from the power supply 10 will first be stepped down by the second voltage reducing resistor 401 and the second voltage reducing capacitor 402, and then the forward current in the alternating current will be blocked by the second reverse diode 404 to form a fluctuating direct current and then flow through the second reverse diode 404. The two Zener diodes 405 stabilize the voltage to form a stable direct current, so as to stably charge the first charging capacitor 221 and the second charging capacitor 223 . In addition, the blocked forward current can also flow back to the power supply 10 through the second forward diode 403, so that the second step-down capacitor 402 can be smoothly charged and discharged.

Similar to the first resistance-capacitance step-down circuit 300 , the second step-down resistor 401 can also convert the alternating current output from the power supply 10 into a low-voltage stable direct current to protect the first charging capacitor 221 and the second charging capacitor 223 .

It can be understood that in other embodiments, the motor control circuit 200 may not include the second charging capacitor 223 , and the second Zener diode 405 may only be connected in parallel with the first charging capacitor 221 .

For the above-mentioned second pressure relief resistor 406, the second pressure relief resistor 406 is connected in parallel with the second step-down capacitor 402, so that when the power supply 10 is disconnected, the second step-down capacitor 402 can quickly drain power.

For the above-mentioned first protection resistor 407, the first protection resistor 407 is also connected in parallel with the second Zener diode 405 to reduce the current of the second Zener diode 405 to protect it.

For the above-mentioned third reverse diode 408, two ends of the third reverse diode 408 are respectively connected to one end of the first charging capacitor 221 and one end of the second Zener diode 405, so as to prevent the electricity of the first charging capacitor 221 from flowing back to the second Resistor-capacitor step-down circuit 400 .

It can be understood that: in other embodiments, the second pressure relief resistor 406 and/or the first protection resistor 407 and/or the third reverse diode 408 may also be omitted, which will not be repeated here. The second resistance-capacitance step-down circuit 400 is not limited to the above description, and may also be other circuits with the same step-down and voltage-stabilizing effects, which will not be repeated here.

For the above blocking circuit 500 , referring to FIG. 2 , the blocking circuit 500 includes a second switch component 501 , a third switch component 502 , a first voltage limiting resistor 503 , a second voltage limiting resistor 504 and a second protection resistor 505 . The third switch assembly 502 is connected to the third output end 234 of the controller 230, the first end of the third switch assembly 502 is connected to the control end of the second switch assembly 501, and the second end of the third switch assembly 502 is connected to the control end of the second switch assembly 501. One end of the power supply 10 is connected to the ground wire. The second switch component 501 is connected in parallel with the first Zener diode 305 .

Wherein, the third switch assembly 502 and the second switch assembly 501 may be selected as PNP type triodes and NPN type triodes, respectively. When the input terminal 231 of the controller 230 detects that the control switch 211 is closed, the third output terminal 234 outputs a square wave with alternating high and low levels. When the third output terminal 234 outputs a low level to the base of the third switch element 502, the collector and the emitter of the third switch element 502 are short-circuited, so that the base of the second switch element 501 receives a high level, The collector and the emitter of the second switch component 501 are short-circuited, so that the first Zener diode 305 is short-circuited, so that it is not supplied with power, thereby reducing power consumption. When the output of the third output terminal 234 is a high level, the collector and the emitter of the third switch element 502 are disconnected, so that the base of the second switch element 501 cannot receive a high level, thereby causing the second switch element The collector and emitter of 501 are disconnected. Further, the first Zener diode 305 restores the power supply to ensure that the power of the first charging capacitor 221 is not consumed, and meets the power supply requirement of the relay 212 after the control switch 211 is turned on. At present, all small household appliances exported to Europe must comply with the EuP certification. EuP certification is the EU's eco-design directive for energy-consuming products. Most household products exported to Europe must meet the 0.5W standby power consumption requirement. In the future, the standby power under the Eup directive The power consumption will be lower, even less than 0.3W. In the present invention, by adjusting the duty ratio of the third output terminal 234, the time interval for restoring the power supply of the first Zener diode 305 can be controlled, thereby reducing the power consumption of the first Zener diode 305 to less than 0.3W.

It should be noted that: the controller 230 controls the mode of the first output terminal 232, the second output terminal 233 and the mode of the third output terminal 234 to output a high level or a low level through the received voltage information of the input terminal 231 All of them can be implemented using the prior art, and the controller 230 can be a single-chip microcomputer or a processor in the prior art, such as an Intel Core i7 processor, an AMD Ryzen 3 processor, and the like.

It can be understood that, in other embodiments, the third switch assembly 502 and the second switch assembly 501 are not limited to the above description, and may also be other switch elements with the same switch function, which will not be described herein again. The third switch assembly 502 may also be omitted, and the control end of the second switch assembly 501 may be directly connected to the third output end 234 of the controller 230 .

For the first voltage limiting resistor 503 and the second voltage limiting resistor 504 , both ends of the first voltage limiting resistor 503 are connected to the third output end 234 and the control end of the third switch component 502 , respectively. Two ends of the second voltage limiting resistor 504 are respectively connected to the first end of the third switch component 502 and the control end of the second switch component 501 . The first voltage limiting resistor 503 and the second voltage limiting resistor 504 are respectively used to reduce the voltages received by the control terminals of the third switch assembly 502 and the second switch assembly 501, so as to protect them.

For the above-mentioned second protection resistor 505 , both ends of the second protection resistor 505 are respectively connected to the other end of the first Zener diode 305 and the second end of the second switch component 501 . The second protection resistor 505 is used for buffering when the second switch element 501 short-circuits the first Zener diode 305 to prevent the second switch element 501 from being burned out.

It can be understood that: in other embodiments, the first voltage limiting resistor 503 and/or the second voltage limiting resistor 505 and/or the second protection resistor 505 may also be omitted, which will not be repeated here.

In the embodiment of the present invention, when the control switch 211 is turned off, the first charging capacitor 221 is charged by the first resistance-capacitance step-down circuit 300 . When the control switch 211 is turned on, the input terminal 231 of the controller 230 detects a voltage change, and the first output terminal 232 outputs a control signal to close the first switch component 213 , so that the coil of the relay 212 and the first charging capacitor 221 form a loop , so that the coil of the relay 212 is powered by the first charging capacitor 221 , and at this time, the first charging capacitor 221 is no longer charged by the first resistance-capacitance step-down circuit 300 . The switch of the relay 212 is connected in series with the motor 20 , and when the coil of the relay 212 is powered, the switch of the relay 212 is closed to make the motor 20 run. At the same time, when the switch of the relay 212 is closed, the first charging capacitor 221 is charged by the second resistance-capacitance step-down circuit 400 to ensure that the coil of the relay 212 is continuously powered. In addition, when the electric motor 20 is powered off after running, the power of the first charging capacitor 221 is exhausted when the power is off, so the coil of the relay 212 is not powered, so the switch of the relay 212 is turned off, so that the first charging capacitor 221 is turned off. The capacitor 221 cannot be charged by the second resistance-capacitance step-down circuit 400, and the motor 20 will not re-run, thereby avoiding the safety problem caused by the motor 20 continuing to run when the power is turned off again. In addition, during the standby process, that is, when the control switch 211 is turned off, the blocking circuit 500 can reduce the power consumption of the first RC step-down circuit 300 without affecting the first RC step-down circuit 300 to the first charging capacitor 221 charging, thus making this circuit more affordable and competitive.

The present invention also provides a mixer, including a motor safety circuit 100 . The motor safety circuit 100 has the same structure and function as the motor safety circuit 100 in the above-mentioned embodiment. For the structure and function of the motor safety circuit 100, reference may be made to the above-mentioned embodiment, which will not be repeated here.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. The scope of the invention should be included in the scope of the claims and description of the present invention. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any manner. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims (9)

1. A motor safety circuit, characterized in that, comprising: The first resistance-capacitance step-down circuit, the motor control circuit and the blocking circuit are connected to each other; it also includes a second resistance-capacitance step-down circuit and a bidirectional thyristor, and the second resistance-capacitance step-down circuit is connected with the motor control circuit; The motor control circuit is used to control the start and stop of the motor; The first resistance-capacitance step-down circuit includes a first Zener diode, the motor control circuit includes a switch circuit, a controller and a charging circuit, the controller is respectively connected with the blocking circuit, the switch circuit and the charging circuit. the charging circuit is connected; the charging circuit is connected with the switch circuit; the first Zener diode is connected with the charging circuit; the bidirectional thyristor is connected with the controller, and the bidirectional thyristor is connected in series with the motor to control the start and stop of the motor; When the switch circuit is in an off state, the motor is in a non-working state, the first Zener diode charges the charging circuit, and the controller controls the blocking by outputting a square wave signal On-off of the circuit; when the blocking circuit is connected, the first Zener diode is short-circuited; The second resistance-capacitance step-down circuit includes a second Zener diode, and the Zener diode is connected to the charging circuit; when the switch circuit is in an on state, the motor is in a working state, and the second resistor is in a working state. The capacitor and step-down circuit charges the charging circuit, and the charging circuit supplies power to the switching circuit. 2. motor safety circuit according to claim 1, is characterized in that, The switch circuit includes a control switch, a relay and a first switch assembly, and the control switch is connected to one end of the charging circuit; The first end of the relay is connected to one end of the power supply, and the second end of the relay is connected to the motor and one end of the second resistance-capacitance step-down circuit, the motor and the second resistance-capacitance step-down circuit The other end of the circuit is connected to the other end of the power supply, wherein the first end and the second end of the relay are two ends of the switch of the relay; The third end of the relay is connected to the control switch, the fourth end of the relay is connected to the first end of the first switch assembly, and the control end of the first switch assembly is connected to the controller, The second end of the first switch assembly is connected to the charging circuit, wherein the third end and the fourth end of the relay are two ends of the coil of the relay; When the control switch is turned on, the third end of the relay is connected to a charging circuit, and the charging circuit supplies power to the coil of the relay. 3. The motor safety circuit according to claim 2, characterized in that, The charging circuit includes a first charging capacitor, the first charging capacitor is connected in parallel with the second resistance-capacitance step-down circuit, and when the control switch is turned off, the first charging capacitor and the first Zener diode are connected in parallel. Parallel connection; when the control switch is turned on, the first charging capacitor and the coil of the relay are connected in parallel. 4. The motor safety circuit according to claim 3, wherein the charging circuit further comprises a second charging capacitor, the first resistance-capacitance step-down circuit further comprises a third Zener diode, and the third voltage regulator The voltage regulator diode is connected in series with the first voltage regulator diode, the third voltage regulator diode is connected in parallel with the second charging capacitor, and both ends of the second charging capacitor are respectively connected to two power supply ports of the controller. 5. The motor safety circuit of claim 1, wherein the blocking circuit comprises a second switch assembly, and the controller comprises a third output; The control terminal of the second switch component is connected to the third output terminal; the second switch component is connected in parallel with the first Zener diode; when the control switch is turned off, the third output terminal outputs high and low A square wave with alternating levels. 6 . The motor safety circuit according to claim 5 , wherein the blocking circuit further comprises a third switch component; the third output terminal is connected to the control terminal of the third switch component; the first The first end of the three-switch assembly is connected to the control end of the second switch assembly, and the second end of the third switch assembly is grounded. 7. The motor safety circuit according to claim 2, wherein, The first resistance-capacitance step-down circuit further includes a first step-down resistor, a first step-down capacitor, a first forward diode and a first reverse diode; One end of the first step-down capacitor is connected to the first step-down resistor, and the other end of the first step-down capacitor is respectively connected to one end of the first forward diode and the first reverse diode; The other end of the first reverse diode is connected to one end of the first Zener diode; When the control switch is turned off, the first Zener diode is connected to the charging circuit; The other end of the first step-down resistor is connected to one end of the power supply, and the other ends of the first forward diode and the first Zener diode are connected to the other end of the power supply; The second resistance-capacitance step-down circuit further includes a second step-down resistor, a second step-down capacitor, a second forward diode and a second reverse diode; Two ends of the second step-down resistor are respectively connected with the second end of the relay and one end of the second step-down capacitor, and the other end of the second step-down capacitor is respectively connected with the second forward diode connected with one end of the second reverse diode; The other end of the second reverse diode is connected to one end of the second Zener diode; the second Zener diode is connected in parallel with the charging circuit; The other ends of the second forward diode and the second Zener diode are connected to the other end of the power supply. 8 . The motor safety circuit according to claim 7 , wherein the first resistance-capacitance step-down circuit further comprises an auxiliary charging capacitor, and the auxiliary charging capacitor is connected in parallel with the first Zener diode. 9 . 9. A mixer, characterized in that it comprises the motor safety circuit of any one of claims 1-8.

Images