CN111198518B

CN111198518B - Cooking appliance and control method thereof

Info

Publication number: CN111198518B
Application number: CN201911047239.3A
Authority: CN
Inventors: 陈舒; 姚斌
Original assignee: Zhejiang Supor Electrical Appliances Manufacturing Co Ltd
Current assignee: Zhejiang Supor Electrical Appliances Manufacturing Co Ltd
Priority date: 2019-10-30
Filing date: 2019-10-30
Publication date: 2022-04-22
Anticipated expiration: 2039-10-30
Also published as: CN111198518A

Abstract

The invention provides a cooking appliance and a control method of the cooking appliance. The cooking appliance comprises a chip, a detection circuit and a control circuit; the chip is provided with a connecting port; the detection circuit has an output end; the control circuit has an input terminal; wherein the output and input terminals are connected to the same connection port. According to the cooking appliance, the output end of the detection circuit and the input end of the control circuit are both connected to the same connection port of the chip, so that the chip can receive the voltage signal of the detection circuit through the connection port to realize detection in the first time period T1, the chip can send the control signal to the control circuit through the connection port to control the operation of the control circuit in the second time period T2, and the first time period T1 and the second time period T2 do not overlap, so that the number of ports of the chip is small, the cost is low, and the cost of the cooking appliance is further reduced.

Description

Cooking appliance and control method thereof

Technical Field

The present invention relates generally to the field of electric heating appliances, and more particularly to a cooking appliance and a control method of the cooking appliance.

Background

The cooking appliance includes a chip 10, a detection circuit 30, and a control circuit 40. As shown in fig. 1, the detection circuit 30 includes a first power input terminal 31, a second resistor 32, a detection element 33, and a second capacitor 34. The detection circuit 30 is connected to a first port of the chip 10 via a first terminal of a second capacitor 34. Control circuit 40 includes a third resistor 42, a transistor 43, a diode 44, a second power input 45, and an actuator 46. The control circuit 40 is connected to a second port of the chip 10, different from its first port, via a first terminal of a third resistor 42. The chip 10 collects the voltage signal of the detection circuit 30 through the first port. The chip 10 sends a control signal to the control circuit 40 through the second port. Thus, the chip needs to be provided with a first port and a second port. It will be appreciated that the number of ports of the chip 10 cannot be less than the total number of detection circuits and control circuits. And the greater the number of ports of the chip 10, the higher its cost. This means that the chip 10 of the conventional cooking device is expensive.

Therefore, there is a need to provide a cooking appliance and a control method of the cooking appliance to at least partially solve the above-mentioned problems.

Disclosure of Invention

In this summary, concepts in a simplified form are introduced that are further described in the detailed description section. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

To at least partially solve the technical problems described above, according to an aspect of the present invention, there is provided a cooking appliance including a chip having a connection port; a detection circuit having an output; a control circuit having an input terminal,

wherein the output and input terminals are connected to the same connection port.

According to the cooking appliance, the output end of the detection circuit and the input end of the control circuit are both connected to the same connection port of the chip, so that the chip can receive the voltage signal of the detection circuit through the connection port to realize detection in the first time period T1, the chip can send the control signal to the control circuit through the connection port to control the operation of the control circuit in the second time period T2, and the first time period T1 and the second time period T2 do not overlap, so that the number of ports of the chip is small, the cost is low, and the cost of the cooking appliance is further reduced.

Optionally, the chip is configured to communicate with at least one of the detection circuit and the control circuit. Thereby, the chip controls the detection circuit and/or the control circuit via one connection port.

Optionally, the chip is configured to communicate with the detection circuit and the control circuit sequentially within one control cycle of the cooking appliance, or to communicate with the control circuit and the detection circuit sequentially within one control cycle of the cooking appliance. Thus, the chip may communicate with the detection circuit to effect detection during one time period and communicate with the control circuit to control operation of the control circuit during another time period in one control cycle.

Optionally, the chip is configured to receive the voltage signal of the detection circuit for a first time period T1 and to send the control signal to the control circuit for a second time period T2 within one control cycle of the cooking appliance, the first time period T1 being smaller than the second time period T2. Therefore, during the process that the chip receives the voltage signal of the detection circuit, the electric energy stored by the second capacitor can enable the actuator to be operated all the time in the first time period T1.

Optionally, the cooking appliance further includes a first resistor, a first end of the first resistor is connected to the output end of the detection circuit, a second end of the first resistor is connected to the connection port, and a resistance value of the first resistor is 100K Ω or more and R or less and 2M Ω or less. Therefore, the first resistor separates the detection circuit from the control circuit, and when the connection port receives a control signal of the detection circuit, the first resistor can control the current value of the current I flowing through the first resistor within a preset range, so that the control circuit can not work due to overlarge current, and the voltage of a voltage signal received by the connection port of the chip can not be low due to undersize current, so that the chip cannot be normally identified.

Alternatively, the first period of time T1 ≦ 1 ms. Thereby, the detection circuit can detect a sufficient amount of voltage signals.

Optionally, the control period T ≧ 1 s. Therefore, the number of voltage signals received by the chip through the detection circuit and the number of control signals sent to the control circuit can be guaranteed while the calculation amount of the chip is reduced.

Optionally, the control circuit further includes a first capacitor, a second end of the first capacitor is connected to the connection port, and a second end of the first capacitor is grounded. Therefore, when the chip does not send a control signal to the control circuit, the electric energy stored in the first capacitor can supply power for the on-off of the control circuit.

Optionally, the capacitance value C of the first capacitor is greater than 100 μ f. Thus, the first capacitor stores enough power to turn the control circuit on for the first time period T1.

Optionally, the detection circuit comprises: the first power supply input end is used for connecting a power supply; the first end of the second resistor is connected with the first power supply input end, and the second end of the second resistor is connected with the output end of the detection circuit; the first end of the detection element is connected with the second end of the second resistor; and a first end of the second capacitor is connected with a second end of the second resistor, and a second end of the second capacitor is connected with a second end of the detection element. Thus, the detection circuit has a simple structure.

Optionally, the control circuit comprises: a first end of the third resistor is connected to the input end of the control circuit: the base electrode of the triode is connected with the second end of the third resistor, and the emitting electrode of the triode is grounded; the anode of the diode is connected with the collector of the triode; the second power supply input end is connected with the cathode of the diode; and the first end of the actuator is connected with the anode of the diode, and the second end of the actuator is connected with the cathode of the diode. Thus, the control circuit has a simple structure.

The invention also provides a control method of the cooking appliance, the control method is used for controlling the cooking appliance, and the control method comprises the following steps:

in one control cycle of the cooking appliance, the chip executes one of the

steps

1 and 2, then executes the other of the

steps

1 and 2,

step 1 is that the chip receives a voltage signal of the detection circuit for a first time period T1;

step 2 is that the chip sends a control signal to the control circuit for a second time period T2.

According to the cooking appliance provided by the invention, when the cooking appliance is in an operating state, the chip can receive the voltage signal of the detection circuit through the connection port in the first time period T1 to realize detection, and the chip can send the control signal to the control circuit through the connection port in the second time period T2 to control the operation of the control circuit, so that the number of ports of the chip is small, the cost is low, and the cost of the cooking appliance is further reduced.

Optionally, the step of the chip receiving the voltage signal of the detection circuit for a first time period T1 and the step of the control circuit sending the control signal to the control circuit for a second time period T2 includes:

starting timing, and judging whether the value of timing duration T1 is T1-T1;

if yes, the chip receives a voltage signal of the detection circuit;

if not, the chip sends a control signal to the control circuit.

Therefore, the step 1 and the step 2 of the control method are simple and convenient to implement.

Optionally, the step of sending a control signal to the control circuit by the chip includes:

judging whether the value of the timing duration T1 is T1 not less than T, if so, resetting T1, carrying out the next control cycle, judging whether the value of the timing duration T1 is T1 not more than T1, and if not, continuing to execute the step of sending a control signal to the control circuit by the chip;

wherein T is T1+ T2.

Thus, the chip communicates with the detection circuit for a first period of time T1 and then communicates with the control circuit for a second period of time T2 in one control cycle.

Drawings

In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings.

FIG. 1 is a schematic diagram of a chip, a control circuit and a detection circuit of a conventional cooking appliance;

FIG. 2 is a schematic diagram of the connection of a chip, control circuitry and detection circuitry in accordance with a preferred embodiment of the present invention; and

fig. 3 is a flowchart illustrating a control method of a cooking appliance according to the present invention.

Description of reference numerals:

10: chip 30: detection circuit

31: first power supply input terminal 32: second resistance

33: the detection element 34: second capacitor

40: the control circuit 42: third resistance

43: the transistor 44: diode with a high-voltage source

45: second power supply input terminal 46: actuator element

110: chip 120: a first resistor

130: the detection circuit 131: a first power supply input terminal

132: second resistance 133: detection element

134: second capacitance 140: control circuit

141: first capacitance 142: third resistance

143: the transistors 144: diode with a high-voltage source

145: second power input terminal 146: actuator element

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that embodiments of the invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in detail so as not to obscure the embodiments of the invention.

In the following description, a detailed structure will be presented for a thorough understanding of embodiments of the invention. It is apparent that the implementation of the embodiments of the present invention is not limited to the specific details familiar to those skilled in the art. The following detailed description of preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.

Hereinafter, a cooking utensil according to a preferred embodiment of the present invention will be described. It is understood that the cooking appliance according to the present invention may be an electromagnetic heating electric rice cooker, an electric pressure cooker, an electric stewpan, or other electric heating appliance. The cooking utensil of the present invention may have various functions such as cooking rice, cooking porridge, etc.

The cooking utensil mainly comprises a pot body and a cover body. The cooker body is provided with a cylindrical inner pot containing part, and the inner pot can be freely placed into or taken out of the inner pot containing part so as to be convenient for cleaning the inner pot. The upper surface of the inner pot has a circular opening for containing materials to be heated, such as rice, soup, etc., into the inner pot. The cover body is pivotally connected to the pot body in an openable and closable manner and is used for covering the pot body. When the cover body is covered on the cooker body, a cooking space is formed between the cover body and the inner pot.

Referring to fig. 2, the cooking appliance includes a chip 110, a first resistor 120, a detection circuit 130, and a control circuit 140.

The connection port of the chip 110 can be switched between an I/O mode and an AD mode. When the connection port of the chip 110 is in the I/O mode, the chip 110 may send a control signal to the outside through the connection port. When the connection port of the chip 110 is in the AD mode, the chip 110 may receive a voltage signal through the connection port.

The connection port of the chip 110 is connected to the second end of the first resistor 120. A first terminal of the first resistor 120 is connected to an output terminal of the detection circuit 130. The second terminal of the first resistor 120 is also connected to an input terminal of the control circuit 140. In this way, when the voltage signal of the detection circuit 130 needs to be received for detection, the connection port of the chip 110 is put in the AD mode. When a control signal needs to be sent to the control circuit 140, the connection port of the chip 110 is put in the I/O mode.

The resistance value of the first resistor 120 is 100K omega and R is less than or equal to 2M omega. Thus, the first resistor 120 separates the control circuit 140 from the detection circuit 130, and when the connection port of the chip 110 is in the AD mode, the voltage signal output by the detection circuit 130 flows to the base of the transistor 143 through the first resistor 120. The current value of the current I passing through the first resistor 120 is reduced to a predetermined range. The current value of the current I at this time cannot turn on the emitter and the collector of the transistor 143. If R < 2M Ω, the current value of the current I is too large, which turns on the emitter and collector of the transistor 143. If R > 100K Ω, the current value of the current I is too small, and at this time, the connection port of the chip 110 cannot read the voltage signal output by the detection circuit 130 normally.

The detection circuit 130 includes a first power input terminal 131, a second resistor 132, a detection element 133, and a second capacitor 134. The sensing element 133 may be a thermistor that senses temperature or a humidity sensor that senses humidity.

The first power input terminal 131 is used for connecting the positive pole of the first power source. The first power supply is a direct current power supply. The first power input terminal 131 is connected to a first terminal of a second resistor 132. A second terminal of the second resistor 132 is connected to a first terminal of the sensing element 133. A second terminal of the detection element 133 is connected to a second terminal of the second capacitor 134. A first terminal of the second capacitor 134 is connected to a first terminal of the detection element 133 (output terminal of the detection circuit 130). A first terminal of the sensing element 133 is connected to a connection port of the chip 110 through the first resistor 120.

When the chip 110 controls the connection port to be in the AD mode, the chip 110 may receive a voltage signal from the detection circuit 130 through the connection port. The first power supply supplies power to the sensing element 133 through the first power input terminal 131 to operate the sensing element 133. The second resistor 132 is connected in series with the sensing element 133, and the second resistor 132 divides the voltage of the sensing element 133 so that the sensing element 133 can generate a voltage signal. The second capacitor 134 is filtered by the detection circuit 130 to stabilize the voltage of the voltage signal output from the detection element 133. This simplifies the structure of the detection circuit 130.

The control circuit 140 includes a third resistor 142, a transistor 143, a diode 144, a second power input 145, and an actuator 146. The actuator 146 may be a fan or a heating coil. The first terminal of the third resistor 142 (the input terminal of the control circuit 140) is connected to the connection port of the chip 110, so that the chip 110 can send a control signal to the control circuit 140 through the connection port when the chip 110 controls the connection port to be in the I/O mode.

A second terminal of the third resistor 142 is connected to a base of the transistor 143. The emitter of transistor 143 is connected to ground. The collector of transistor 143 is connected to the anode of diode 144. The cathode of the diode 144 is connected to the second power input terminal 145. The second power input 145 is for connection to the anode of a second power supply. The second power supply may be a dc power supply. The cathode of diode 144 is connected to a first terminal of an actuator 146. The anode of diode 144 is connected to the second terminal of actuator 146. Thus, the second power supply provides power to the actuator 146 to operate the actuator 146. The third resistor 142 may limit the amount of current that enters the base of the transistor 143, thereby protecting the transistor 143. At the time of controlling the on/off of the transistor 143, the diode 144 can prevent the actuator 146 from generating a high voltage in a momentary reverse direction at the collector of the transistor 143, thereby protecting the transistor 143. This simplifies the structure of the control circuit 140.

The control circuit further comprises a first capacitor 141. A first terminal of the first capacitor 141 is connected to a base of the transistor 143. A second terminal of the first capacitor 141 is connected to an emitter of the transistor 143. Thus, when the chip 110 does not send a control signal to the control circuit 140 (when the connection port of the chip 110 is in the AD mode), the power stored in the first capacitor 141 can supply power for turning on and off the control transistor 143.

Preferably, the capacitance value C of the first capacitor 141 is > 100 μ f. Thus, the first capacitor 141 stores enough power to turn on the control circuit 140 during the first time period T1, so that the actuator 146 can operate stably.

In this embodiment, the output terminal of the detection circuit 130 and the input terminal of the control circuit 140 are both connected to the same connection port of the chip 110, so that the chip 110 can receive the voltage signal of the detection circuit 130 through the connection port to realize detection in the first time period T1, the chip 110 can send the control signal to the control circuit 140 through the connection port to control the operation of the control circuit in the second time period T2, and the first time period T1 and the second time period T2 do not overlap, so that the number of ports of the chip 110 is small, the cost is low, and the cost of the cooking appliance is further reduced.

Preferably, the first period of time T1 is less than the second period of time T2. Thus, during the time that the chip 110 receives the voltage signal of the detection circuit 130, the second capacitor 134 stores the electric energy to enable the actuator 146 to operate for the first time period T1.

Preferably, the first period of time T1 ≦ 1 ms. Thereby, the detection circuit 130 can detect a sufficient amount of voltage signals.

Preferably, the control period T ≧ 1 s. Thus, the amount of calculation of the chip 110 can be reduced while ensuring the number of voltage signals collected by the chip 110 through the detection circuit 130 and the number of control signals transmitted to the control circuit 140.

In the present embodiment, the states of the cooking appliance include a standby state, a detection state, and an operating state. When the cooking appliance is in the standby state, neither the detection circuit 130 nor the control circuit 140 is operated. At this time, the chip 110 neither receives the voltage signal of the detection circuit 130 nor transmits a control signal to the control circuit 140.

When the cooking appliance is in the detection state, the detection circuit 130 operates normally. The control circuit 140 does not operate. At this time, the chip 110 puts the connection port in the AD mode to receive the voltage signal of the detection circuit 130. At this time, the chip 110 does not send a control signal to the control circuit 140.

When the cooking appliance is in the operating state, the detection circuit 130 and the control circuit 140 operate normally. At this time, the chip 110 switches the connection port between the AD mode and the I/O mode to receive the voltage signal of the detection circuit 130 or to transmit the control signal to the control circuit 140.

The invention also provides a control method of the cooking appliance. The control method includes the chip 110 performing one of the

steps

1 and 2 and then performing the other of the

steps

1 and 2 during one control cycle of the cooking appliance.

Step 1, the chip 110 receives the voltage signal of the detection circuit 130 for a first time period T1.

Step 2, the chip 110 sends a control signal to the control circuit 140 for a second time period T2.

When the cooking appliance is in the working state, the control method of the chip 110 is as shown in fig. 3, and includes:

step S1, the cooking utensil is turned on and step S2 is executed.

In step S2, the chip 110 starts timing, and step S3 is executed.

In this embodiment, the chip 110 may be clocked by a counter.

And step S3, judging whether the value of the timing duration T1 is T1 not more than T1, if so, executing step S4, otherwise, executing step S5.

Step S4, the connection port is in the AD mode to receive the voltage signal of the detection circuit 130, thereby completing the detection. The execution returns to step S2.

Step S5 is to put the connection port in I/O mode to send a control signal to the control circuit 140 to control the operation of the actuator 146. Step S6 is executed.

And step S6, judging whether the value of T1 is T1 is not less than T, if so, executing step S7, otherwise, returning to continue executing step S5.

Step S7 is a step S2 of resetting t1 so that t1 becomes 0 (initial value), executing the next control cycle, and executing the next control cycle.

If T1 ≧ T at step S6, which indicates the end of one control cycle of the cooking appliance, the next control cycle is performed to execute step S2 of the next control cycle.

If T1 < T of step S6 indicates that one control cycle of the cooking appliance has not ended, the process returns to and continues with step S5 of the current control cycle.

Therefore, the method of the step 1 and the step 2 is simple and convenient to implement. The chip 110 communicates with the detection circuit 130 for a first time period T1 and then communicates with the control circuit 140 for a second time period T2 in one control cycle.

In the present embodiment, step 1 is executed first, and then step 2 is executed. In an embodiment not shown, step 1 and then step 2 may be performed.

In this embodiment, when the cooking appliance is in the operating state, the chip 110 may receive the voltage signal of the detection circuit 130 through the connection port during the first time period T1 to implement the detection, and the chip 110 may send the control signal to the control circuit 140 through the connection port during the second time period T2 to control the operation of the control circuit, so that the number of ports of the chip 110 is small, the cost is low, and the cost of the cooking appliance is further reduced.

The chip 110 is in communication with at least one of the control circuit and the detection circuit. Thus, the chip 110 controls the detection circuit and/or the control circuit through one connection port.

The chip 110 communicates with the detection circuit 130 and the control circuit 140 sequentially within one control cycle of the cooking appliance, or communicates with the control circuit 140 and the detection circuit 130 sequentially within one control cycle of the cooking appliance. In this way, chip 110 may communicate with detection circuit 130 to perform detection during one period of a control cycle and communicate with control circuit 140 to control the operation of control circuit 140 during another period of time.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Terms such as "component" and the like, when used herein, can refer to either a single part or a combination of parts. Terms such as "mounted," "disposed," and the like, as used herein, may refer to one component as being directly attached to another component or one component as being attached to another component through intervening components. Features described herein in one embodiment may be applied to another embodiment, either alone or in combination with other features, unless the feature is otherwise inapplicable or otherwise stated in the other embodiment.

The present invention has been described in terms of the above embodiments, but it should be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the invention to the scope of the described embodiments. It will be appreciated by those skilled in the art that many variations and modifications may be made to the teachings of the invention, which fall within the scope of the invention as claimed.

The flows described in all the preferred embodiments described above are only examples. Unless an adverse effect occurs, various processing operations may be performed in a different order from the order of the above-described flow. The above-mentioned steps of the flow can be added, combined or deleted according to the actual requirement.

Further, the commands, command numbers, and data items described in all the preferred embodiments described above are only examples, and thus the commands, command numbers, and data items may be set in any manner as long as the same functions are achieved. The units of the terminal of the preferred embodiments may also be integrated, further divided or subtracted according to actual needs.

Claims

1. A cooking appliance, characterized in that it comprises:

a chip (110), the chip (110) having a connection port;

a detection circuit (130), the detection circuit (130) having an output;

the control circuit (140), the control circuit (140) has an input end, the control circuit (140) further includes a first capacitor (141) and a transistor (143), a first end of the first capacitor (141) is connected to the connection port and a base of the transistor (143), a second end of the first capacitor (141) is grounded, and an emitter of the transistor (143) is grounded;

wherein the output terminal and the input terminal are connected with the same connecting port;

the chip (110) is configured to communicate with at least one of the detection circuit (130) and the control circuit (140);

the cooking appliance receives the voltage signal of the detection circuit (130) for a first period of time T1 within one control cycle and sends a control signal to the control circuit (140) for a second period of time T2 within the one control cycle, the first period of time T1 being less than the second period of time T2.

2. The cooking appliance according to claim 1, wherein the chip (110) is configured to communicate with the detection circuit and the control circuit successively within the one control cycle of the cooking appliance or to communicate with the control circuit and the detection circuit successively within the one control cycle of the cooking appliance.

3. The cooking appliance according to claim 1, further comprising a first resistor (120), wherein a first end of the first resistor (120) is connected to the output terminal of the detection circuit (130), a second end of the first resistor (120) is connected to the connection port, and a resistance of the first resistor (120) is 100K Ω ≦ R ≦ 2M Ω.

4. The cooking appliance of claim 1, wherein the first time period T1 is ≦ 1 ms.

5. The cooking appliance of claim 1, wherein the control period T ≧ 1 s.

6. The cooking appliance according to claim 1, wherein the first capacitance (141) has a capacitance value C > 100 μ f.

7. The cooking appliance according to claim 1, wherein the detection circuit (130) comprises:

a first power input (131), the first power input (131) for connecting to a power source;

a second resistor (132), a first terminal of the second resistor (132) being connected to the first power input terminal (131), a second terminal of the second resistor (132) being connected to the output terminal of the detection circuit (130);

a sensing element (133), a first end of the sensing element (133) being connected to the second end of the second resistor (132);

a second capacitor (134), a first end of the second capacitor (134) is connected to the second end of the second resistor (132), and a second end of the second capacitor (134) is connected to a second end of the detection element (133).

8. The cooking appliance of claim 1, wherein the control circuit (140) further comprises:

a third resistor (142), a first terminal of the third resistor (142) being connected to the input terminal of the control circuit (140); the anode of the diode (144) is connected with the collector of the triode (143);

a second power input (145), said second power input (145) being connected to the cathode of said diode (144);

an actuator (146), a first end of the actuator (146) is connected to the anode of the diode (144), and a second end of the actuator (146) is connected to the cathode of the diode (144);

the base electrode of the triode (143) is connected with the second end of the third resistor (142).

9. A control method of a cooking appliance, the control method being for controlling the cooking appliance of claim 1, the control method comprising:

the chip (110) performs one of the steps 1 and 2 and then performs the other of the steps 1 and 2 during one control cycle of the cooking appliance,

wherein, the step 1 is that the chip (110) receives the voltage signal of the detection circuit (130) for a first time period T1;

the step 2 is that the chip (110) sends a control signal to the control circuit (140) for a second time period T2.

10. The method of claim 9, wherein the chip (110) receives the voltage signal of the detection circuit (130) for a first time period T1, and the step of the control circuit (140) sending the control signal to the control circuit (140) for a second time period T2 comprises:

starting timing, and judging whether the value of timing duration T1 is T1-T1;

if yes, the chip (110) receives the voltage signal of the detection circuit (130);

if not, the chip (110) sends the control signal to the control circuit (140).

11. The method of claim 10, wherein the step of the chip (110) sending the control signal to the control circuit (140) comprises:

judging whether the value of the timing duration T1 is T1 which is not less than T, if so, resetting the T1, carrying out the next control cycle, judging whether the value of the timing duration T1 is T1 which is not more than T1, and if not, continuing to execute the step of sending the control signal to the control circuit (140) by the chip (110);

wherein T is T1+ T2.