Control circuit and microwave oven

Abstract

The utility model provides a control circuit and a microwave oven. The circuit comprises an MCU, a driving chip U2, a gate circuit module, a relay module and an optocoupler module. The MCU is electrically connected with one end of the driving chip U2 and one end of the optocoupler module, the gate circuit module is arranged on the driving chip U2 in parallel, the other end of the driving chip U2 is connected with one end of the relay module, and the other ends of the relay module and the optocoupler module are connected with the power supply; according to the control circuit and the microwave oven, the structure of the circuit can be simplified, the sound generated when the control circuit drives a load to operate is reduced, the stability of the circuit can be improved, and the service life of the microwave oven is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of microwave oven, specifically, control circuit and microwave oven. BACKGROUND

[0002] With the increasing of people's quality of life, the use of microwave oven becomes more and more common. At present, most of the electric control scheme of microwave oven uses relay to control all loads. Too many relays will cause the sound of multiple relays to be too loud during the starting process of the microwave oven, resulting in poor user experience. Moreover, when the number of times of attracting the relay contact is too large, the relay will gradually reach the service life of the device, which will further cause the user to be unable to normally use the microwave oven. Therefore, it is of great significance to study how to improve the stability of the electric control device driving the load operation, reduce the sound of the electric control device driving the load operation, and prolong the service life of the electric control device.

[0003] In the patent with publication number CN117212850A, a new microwave oven with low-power zero-crossing detection circuit and control method are mentioned. The circuit includes a zero-crossing detection circuit, a main controller, an N-line controller, and a heating load. The zero-crossing detection circuit is used to receive an AC signal and send a zero-crossing signal to the main controller when the AC signal crosses zero. The main controller controls the on-off function of the heating load according to the zero-crossing signal. The N-line controller includes a relay switch connected to the N-line of the microwave oven power supply. The N-line input of the zero-crossing detection circuit is connected to the relay switch, and the relay switch controls the on-off of the N-line input of the zero-crossing detection circuit power supply. In this way, the service life of the optocoupler can be extended. However, on the one hand, since the circuit uses the switch of the oven lamp relay as the condition for enabling the zero-crossing detection circuit, the problem of excessive loud sound during the starting of the microwave oven cannot be solved by the circuit. On the other hand, since the gate circuit and the relay are directly connected in the circuit, it can be seen that the patent still uses the relay to drive all loads. During the starting process of the microwave oven, not only is the sound loud, but also the number of times of attracting the relay is large, which can easily cause the service life of the microwave oven to be shortened. SUMMARY

[0004] Therefore, the utility model aims at providing a control circuit and a microwave oven to solve the problem of excessive loud sound during the starting of the microwave oven caused by the use of relays to control all loads in the prior art, and to solve the problem of shortened service life of the microwave oven caused by too many times of attracting the relay. In this way, the structure of the circuit can be simplified, the sound of the control circuit driving the load operation can be reduced, the stability of the circuit can be improved, and the service life of the microwave oven can be prolonged.

[0005] In order to achieve the above object, the technical scheme of the utility model is as follows:

[0006] The utility model relates to a kind of control circuit and microwave oven, and the control circuit includes MCU, drive chip U2, gate circuit module, relay module and photocoupler module;MCU is electrically connected with drive chip U2, one end of photocoupler module respectively, gate circuit module is connected in parallel on drive chip U2, the other end of drive chip U2 is connected with one end of relay module, and the other end of relay module, photocoupler module is all connected with power supply.

[0007] Further, the pin VCC of MCU is connected with the first power supply Vcc, and the pin 1-6 of MCU is connected with the pin 2-7 of drive chip U2 respectively;The pin 7,8 of MCU is connected with photocoupler module.

[0008] Further, the circuit includes fourth capacitor C4, and the two ends of fourth capacitor C4 are electrically connected with the pin 2 of MCU and the pin 3 of drive chip U2 respectively.

[0009] Further, the pin 1,16 of drive chip U2 is electrically connected with the two ends of gate circuit module respectively.

[0010] Further, gate circuit module includes door detection switch CN0 and electrolytic capacitor E6;The pin 3 of door detection switch CN0 is connected with the pin 1 of drive chip U2, and the pin 1 of door detection switch CN0 is connected with one end of electrolytic capacitor E6 in parallel and then grounded, and the other end of electrolytic capacitor E6 is connected with the pin 16 of drive chip U2.

[0011] Further, relay module includes relay one component, relay two components, first load and second load;The two ends of relay one component coil are electrically connected with drive chip U2 and second power supply VDD respectively, and one end of relay one component contact is electrically connected with the pin ACL of power supply through first load respectively;The other end of relay one component contact is connected with the pin ACN of power supply;One end of relay two component coil is electrically connected with drive chip U2, and the other end of relay two component coil is connected with second power supply VDD and one end of second load respectively, and the other end of second load is electrically connected with drive chip U2.

[0012] Further, three relay one components, first loads are arranged uniformly, three relay one components are relay one CONV1, relay two GRILL and relay three VPC1 respectively, three first loads are first heating pipe T1, second heating pipe T2 and microwave device CN1 respectively, one end of relay one CONV1, relay two GRILL and relay three VPC1 coils are electrically connected with pin 14, 13 and 12 of driving chip U2 respectively, the other end of relay one CONV1, relay two GRILL and relay three VPC1 coils are electrically connected with second power supply VDD, one end of relay one CONV1, relay two GRILL and relay three VPC1 contacts are connected with pin ACL of power supply through first heating pipe T1, second heating pipe T2 and microwave device CN1 respectively, the other end of relay one CONV1, relay two GRILL and relay three VPC1 contacts are connected with pin ACN of power supply.

[0013] Further, relay two component is relay four MAIN, second load includes fifth resistance R5 and loudspeaker, one end of relay four MAIN coil is electrically connected with pin 11 of driving chip U2, the other end of relay four MAIN coil is connected with second power supply VDD, fifth resistance R5 and one end of loudspeaker in parallel, the other end of fifth resistance R5 and loudspeaker is electrically connected with pin 10 of driving chip U2.

[0014] Further, the optical coupling module includes an optical coupling, a current limiting resistor and a motor, one end of the optical coupling input side is connected with the first power supply Vcc through the current limiting resistor, the other end of the optical coupling input side is connected with the MCU, one end of the optical coupling output side is connected with the pin ACL of the power supply through the motor, the other end of the optical coupling output side is connected with the pin ACN of the power supply, the optical coupling, the current limiting resistor and the motor are arranged at least two.

[0015] A microwave oven, the microwave oven includes the control circuit, the circuit is arranged in the microwave oven.

[0016] Compared with the prior art, the control circuit and the microwave oven have the following beneficial effects:

[0017] Through the arrangement of the control circuit in the microwave oven, the structure of the circuit can be simplified, the sound of the control circuit driving the load to operate can be reduced, the stability of the circuit can be improved, the problem that the service life of the microwave oven is affected due to the large number of times of relay attraction can be avoided, and the service life of the microwave oven can be prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0018] The accompanying drawings, which form a part of this description, are included to provide a further understanding of the application. Embodiments of the application and its equivalents are described with reference to the drawings. In the drawings:

[0019] Figure 1 The control circuit is shown in the schematic diagram.

[0020] Reference signs: 11, gate circuit module; 12, relay module; 121, first relay component; 122, second relay component; 123, first load; 124, second load; 13, optocoupler module. DETAILED DESCRIPTION

[0021] The utility novel concepts of the present disclosure will be described below using terms commonly employed by those skilled in the art to convey the substance of their work to others skilled in the art. However, these utility novel concepts can be embodied in many different forms, and thus should not be considered limited to the embodiments described herein.

[0022] It should be noted that the embodiments in the present utility novel and the features in the embodiments can be combined with each other without conflict.

[0023] The present utility novel will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0024] The present embodiment is directed to a microwave oven, which is the same as a conventional microwave oven in that the overall structure is composed of an oven door, an oven body, and an electric wire.

[0025] In order to solve the problem that the existing microwave oven in the prior art uses a relay to control all loads, which is easy to cause the microwave oven to produce a loud sound during startup, and also easy to cause the microwave oven to have a shortened service life due to too many times of relay attraction, the present embodiment proposes a control circuit and a microwave oven. The control circuit comprises an MCU, a driving chip U2, a gate circuit module 11, a relay module 12, and an optocoupler module 13. The MCU is electrically connected to the driving chip U2 and one end of the optocoupler module 13, respectively. The gate circuit module 11 is connected in parallel to the driving chip U2. The other end of the driving chip U2 is connected to one end of the relay module 12. The other ends of the relay module 12 and the optocoupler module 13 are both connected to a power supply.

[0026] Unlike the conventional control of all loads by using an attraction type relay, which is easy to cause the microwave oven to produce a loud sound during startup, the setting of the control circuit in the microwave oven according to the present application can simplify the structure of the circuit, reduce the sound produced by the control circuit driving the load to run, and also improve the stability of the circuit, avoid the problem that the service life of the microwave oven is affected due to too many times of relay attraction, and thus prolong the service life of the microwave oven.

[0027] The pin VCC of the MCU is connected with the first power supply Vcc, the pin GND of the MCU is grounded, and the pins 1-6 of the MCU are respectively connected with the pins 2-7 of the driving chip U2. The pins 7 and 8 of the MCU are connected with the optical coupling module 13. The value of the first power supply Vcc is set according to the requirement, preferably, the value of Vcc is +5V. In addition, the circuit comprises a fourth capacitor C4, and the two ends of the fourth capacitor C4 are respectively connected with the pin 2 of the MCU and the pin 3 of the driving chip U2.

[0028] Through the cooperation between the MCU and the driving chip U2, the control accuracy of the circuit on the relay module 12 and the optical coupling module 13 can be improved, the signal interference phenomenon is avoided when a single control chip controls the relay module 12 and the optical coupling module 13 at the same time, and thus the stability of the circuit is improved, and the flexibility and reliability of the circuit in controlling each component are enhanced.

[0029] The pins 1 and 16 of the driving chip U2 are respectively connected with the two ends of the gate circuit module 11. The pin 15 of the driving chip U2 is connected with the first power supply Vcc, the pin 8 of the driving chip U2 is grounded, and the pin 9 of the driving chip U2 is connected with the second power supply VDD. The pins 10-14 of the driving chip U2 are connected with the relay module 12. The value of the second power supply VDD is set according to the requirement, preferably, the value of VDD is +12V.

[0030] Through the cooperation of the driving chip U2, the gate circuit module 11 and the relay module 12, the driving chip U2 can share some tasks of the MCU, improve the running speed of the MCU, reduce the delay between each component in the circuit, and improve the overall running efficiency of the circuit.

[0031] The gate circuit module 11 comprises a door detection switch CN0 and an electrolytic capacitor E6. The pin 3 of the door detection switch CN0 is connected with the pin 1 of the driving chip U2, the pin 1 of the door detection switch CN0 is connected with one end of the electrolytic capacitor E6 in parallel and then grounded, and the other end of the electrolytic capacitor E6 is connected with the pin 16 of the driving chip U2.

[0032] Through the setting of each component in the gate circuit module 11, the accuracy of detecting the opening and closing state of the furnace door can be improved, and the filtering and coupling effects can be achieved, so as to guarantee the reliability of the detection result of the opening and closing state of the furnace door.

[0033] The relay module 12 comprises a relay one component 121, a relay two component 122, a first load 123 and a second load 124. Two ends of the coil of the relay one component 121 are electrically connected with the driving chip U2 and the second power supply VDD respectively, one end of the contact of the relay one component 121 is electrically connected with the pin ACL of the power supply through the first load 123 respectively; the other end of the contact of the relay one component 121 is connected with the pin ACN of the power supply. One end of the coil of the relay two component 122 is electrically connected with the driving chip U2, the other end of the coil of the relay two component 122 is connected with the second power supply VDD and one end of the second load 124 respectively, the other end of the second load 124 is electrically connected with the driving chip U2. Among them, the relay one component 121 and the first load 123 are at least provided with two. The relay one component 121 and the first load 123 are one-to-one corresponding.

[0034] Specifically, when the relay one component 121 and the first load 123 are provided with three, the three relay one components 121 are relay one CONV1, relay two GRILL and relay three VPC1 respectively. The three first loads 123 are the first heating pipe T1, the second heating pipe T2 and the microwave device CN1 respectively. One end of the coil of the relay one CONV1, the relay two GRILL and the relay three VPC1 is electrically connected with the pins 14, 13 and 12 of the driving chip U2 respectively; the other end of the coil of the relay one CONV1, the relay two GRILL and the relay three VPC1 is electrically connected with the second power supply VDD. One end of the contact of the relay one CONV1, the relay two GRILL and the relay three VPC1 is connected with the pin ACL of the power supply through the first heating pipe T1, the second heating pipe T2 and the microwave device CN1 respectively; the other end of the contact of the relay one CONV1, the relay two GRILL and the relay three VPC1 is connected with the pin ACN of the power supply. The relay two component 122 is relay four MAIN, the second load 124 comprises the fifth resistor R5 and the loudspeaker, one end of the coil of the relay four MAIN is electrically connected with the pin 11 of the driving chip U2, the other end of the coil of the relay four MAIN is connected with the second power supply VDD, one end of the fifth resistor R5 and the loudspeaker respectively, the other end of the fifth resistor R5 and the loudspeaker is connected in parallel and is electrically connected with the pin 10 of the driving chip U2. Among them, the microwave device CN1 comprises any one combination form of the microwave transformer and the magnetron, the microwave frequency conversion board and the magnetron. The relay three VPC1 is a microwave relay.

[0035] Through the setting of each relay and load, the stable operation of the circuit can be effectively realized, and under the action of the loudspeaker, the sound prompt before and after the microwave oven works can be realized; it is convenient to remind the user to perform the next operation, and it is beneficial to improve the use convenience of the user.

[0036] The light coupling module 13 includes a light coupling, a current limiting resistor and a motor. One end of the light coupling input side is connected with the first power supply Vcc through the current limiting resistor, the other end of the light coupling input side is connected with the MCU, one end of the light coupling output side is connected with the pin ACL of the power supply through the motor, and the other end of the light coupling output side is connected with the pin ACN of the power supply. The light coupling, the current limiting resistor and the motor are at least provided with two.

[0037] Specifically, when the light coupling, the current limiting resistor and the motor are provided with two, the two light couplings are light coupling CFan1 and light coupling VFAN1, the two current limiting resistors are first resistor R1 and second resistor R2, and the two motors are first motor CFan and second motor VFAN. The first resistor R1, the second resistor R2, the light coupling CFan1, the light coupling VFAN1, the first motor CFan and the second motor VFAN. One end of the input side of the light coupling CFan1 and the light coupling VFAN1 is respectively connected with the first power supply Vcc through the first resistor R1 and the second resistor R2, and the other end of the input side of the light coupling CFan1 and the light coupling VFAN1 is respectively connected with the pin 7 and the pin 8 of the MCU. One end of the output side of the light coupling CFan1 and the light coupling VFAN1 is respectively connected with the pin ACL of the power supply through the first motor CFan and the second motor VFAN, and the other end of the output side of the light coupling CFan1 and the light coupling VFAN1 is connected with the pin ACN of the power supply. The light coupling CFan1 and the light coupling VFAN1 are both light coupling MOS semiconductors. It should be noted that as long as the relay CONV1, the GRILL, the VPC1 and the MAIN are driven, the pin ACN of the power supply will be connected with the corresponding load, so that the corresponding load forms a loop and works.

[0038] By using the light coupling MOS semiconductor to replace the traditional relay, the light coupling MOS semiconductor is used to replace the attracted relay. When the light coupling MOS semiconductor controls the conduction of the circuit in the microwave oven, there is no noise, and the service life of the light coupling MOS semiconductor is much higher than that of the attracted relay, so that the problem of service life is not considered, and the user's experience of using the microwave oven is greatly improved.

[0039] A microwave oven includes the control circuit, and the circuit is arranged in the microwave oven.

[0040] Working principle:

[0041] When CN0 detects that the oven door is closed, the user plugs in the power, the ACL power supply is connected to each load end, as long as the relay CONV1, GRILL, VPC1, optocoupler CFan1, VFAN1 has output low level control signal, the corresponding load of the relay and optocoupler will be started. The user needs to control the microwave oven, at this time, the IO8 of U1, that is, the pin 8 of the MCU outputs a low level signal to control the VFAN1 optocoupler MOS semiconductor to start the VFAN motor to drive the VPC cooling fan to work, and R2 is the current limiting resistor of the VFAN1 optocoupler MOS semiconductor. Then U1 controls IO2, that is, the pin 2 of the MCU outputs a high level, and the corresponding U2 outputs a low level to control the MAIN relay to be attracted, and then U1 controls IO5, that is, the pin 5 of the MCU outputs a high level, and the corresponding U2 outputs a low level to control the VPC1 relay to be attracted. At this time, the microwave function of the microwave oven works. At this time, only two attracted relays work, and the VPC cooling fan is controlled by the optocoupler MOS semiconductor.

[0042] When the user needs to start the hot air function, at this time, the MCU controls IO3, that is, the pin 3 outputs a high level, and the corresponding U2 outputs a low level to control the CONV1 relay to be attracted, and the hot air pipe works. Within a certain time, the MCU controls IO7, that is, the pin 7 outputs a low level to control the hot air CFan motor to drive the fan to work through the CFan1 optocoupler MOS semiconductor, and R1 is the current limiting resistor of the CFan1 optocoupler MOS semiconductor. The cavity temperature control process also heats the GRILL, and the MCU controls IO4, that is, the pin 4 outputs a high level, and the corresponding U2 outputs a low level to control the GRILL relay to be attracted, so as to achieve the corresponding menu function. At this time, in the hot air mode, one attracted relay works, and the CFan motor is controlled by the CFan1 optocoupler MOS semiconductor. And in the working process, the CFan motor and the CONV relay are turned on and off many times, and the sound of the working relay is also reduced.

[0043] In the utility model, for any microwave oven, can include the control circuit structure described in the embodiment, and on the basis of the related structure and assembly relationship of the heating pipe and motor provided in the embodiment, the microwave oven further includes the conventional components such as oven door, oven body, wire and the like, in view of the fact that they are prior art, no further description is made here.

[0044] The above only describes the preferred embodiment of the utility model, and does not limit the utility model, and any modification, equivalent replacement, improvement, etc. within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A control circuit, characterized by The circuit comprises an MCU, a driving chip U2, a gate circuit module (11), a relay module (12) and an optocoupler module (13); the MCU is electrically connected with the driving chip U2 and one end of the optocoupler module (13) respectively, the gate circuit module (11) is arranged in parallel on the driving chip U2, the other end of the driving chip U2 is connected with one end of the relay module (12), and the other ends of the relay module (12) and the optocoupler module (13) are connected with a power supply.

2. A control circuit according to claim 1, characterised in that The pin VCC of the MCU is connected with a first power supply Vcc, the pins 1-6 of the MCU are connected with the pins 2-7 of the driving chip U2 respectively, and the pins 7 and 8 of the MCU are connected with the optocoupler module (13).

3. A control circuit according to claim 2, characterised in that, The circuit comprises a fourth capacitor C4, and the two ends of the fourth capacitor C4 are electrically connected with the pin 2 of the MCU and the pin 3 of the driving chip U2 respectively.

4. The control circuit of claim 1, wherein, The pins 1 and 16 of the driving chip U2 are electrically connected with the two ends of the gate circuit module (11) respectively.

5. A control circuit according to claim 4, characterised in that, The gate circuit module (11) comprises a gate detection switch CN0 and an electrolytic capacitor E6; the pin 3 of the gate detection switch CN0 is connected with the pin 1 of the driving chip U2, the pin 1 of the gate detection switch CN0 is connected with one end of the electrolytic capacitor E6 in parallel and then grounded, and the other end of the electrolytic capacitor E6 is connected with the pin 16 of the driving chip U2.

6. A control circuit according to claim 1, wherein, The relay module (12) comprises a relay one component (121), a relay two component (122), a first load (123) and a second load (124); the two ends of the coil of the relay one component (121) are electrically connected with the driving chip U2 and a second power supply VDD respectively, one end of the contact of the relay one component (121) is electrically connected with the pin ACL of the power supply through the first load (123) respectively, and the other end of the contact of the relay one component (121) is connected with the pin ACN of the power supply; one end of the coil of the relay two component (122) is electrically connected with the driving chip U2, the other end of the coil of the relay two component (122) is connected with the second power supply VDD and one end of the second load (124) respectively, and the other end of the second load (124) is electrically connected with the driving chip U2.

7. A control circuit according to claim 6, characterised in that The relay one component (121) and the first load (123) are all arranged in three, the three relay one components (121) are a relay one CONV1, a relay two GRILL and a relay three VPC1 respectively, the three first loads (123) are a first heating pipe T1, a second heating pipe T2 and a microwave device CN1 respectively, one end of the coil of the relay one CONV1, the relay two GRILL and the relay three VPC1 is electrically connected with the pins 14, 13 and 12 of the driving chip U2 respectively, the other end of the coil of the relay one CONV1, the relay two GRILL and the relay three VPC1 is electrically connected with the second power supply VDD, one end of the contact of the relay one CONV1, the relay two GRILL and the relay three VPC1 is connected with the pin ACL of the power supply through the first heating pipe T1, the second heating pipe T2 and the microwave device CN1 respectively, and the other end of the contact of the relay one CONV1, the relay two GRILL and the relay three VPC1 is connected with the pin ACN of the power supply.

8. A control circuit according to claim 6, wherein, The relay second component (122) is relay MAIN, and the second load (124) includes the fifth resistor R5 and a horn, one end of the relay MAIN coil is electrically connected with the pin 11 of the driving chip U2, the other end of the relay MAIN coil is respectively connected with the second power supply VDD, the fifth resistor R5 and one end of the horn, the other ends of the fifth resistor R5 and the horn are connected in parallel and are electrically connected with the pin 10 of the driving chip U2.

9. The control circuit of claim 1, wherein, The opto-coupler module (13) comprises an opto-coupler, a current-limiting resistor and a motor, one end of the input side of the opto-coupler is connected with the first power supply Vcc through the current-limiting resistor, the other end of the input side of the opto-coupler is connected with the MCU, one end of the output side of the opto-coupler is connected with the pin ACL of the power supply through the motor, the other end of the output side of the opto-coupler is connected with the pin ACN of the power supply, and the opto-coupler, the current-limiting resistor and the motor are at least provided with two.

10. A microwave oven characterized by comprising: The microwave oven comprises a control circuit according to any one of claims 1-9, and the circuit is arranged in the microwave oven.

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