阅读说明：本技术 烹饪器具的控制方法和烹饪器具 (Control method of cooking appliance and cooking appliance ) 是由 刘世强 姚斌 于 2019-12-23 设计创作，主要内容包括：本发明公开了一种烹饪器具的控制方法和烹饪器具。烹饪器具设置有红外检测装置,红外检测装置包括用于发射红外线的红外线发射装置和用于接收红外线的红外线接收装置,控制方法包括：向红外线发射装置发送占空比为预设占空比值P的控制信号,以使红外线发射装置发出红外线；判断红外线接收装置是否接收到红外线发射装置发出的红外线,若否,则判定烹饪器具处于沸腾状态。由此,在烹饪器具中设置红外线检测装置,以通过红外线检测蒸汽空间内的蒸汽浓度,进而判定烹饪器具内的液体是否沸腾,由此判定烹饪器具内的液体沸腾准确,可靠性高,不受烹饪器具所在地方的海拔影响。(The invention discloses a cooking appliance and a control method thereof. The cooking utensil is provided with infrared detection device, and infrared detection device includes the infrared emission device that is used for emitting infrared ray and is used for receiving the infrared receiving device of infrared ray, and the control method includes: sending a control signal with a duty ratio of a preset duty ratio value P to the infrared emission device so as to enable the infrared emission device to emit infrared rays; and judging whether the infrared receiving device receives the infrared rays emitted by the infrared emitting device, and if not, judging that the cooking utensil is in a boiling state. Therefore, the infrared detection device is arranged in the cooking appliance, so that the steam concentration in the steam space is detected through infrared rays, whether liquid in the cooking appliance boils or not is judged, the liquid in the cooking appliance is judged to be boiled accurately, the reliability is high, and the cooking appliance is not influenced by the altitude of the place where the cooking appliance is located.)

1. A control method of a cooking appliance, characterized in that the cooking appliance is provided with infrared detection means comprising infrared emission means (121) for emitting infrared rays and infrared reception means (122) for receiving the infrared rays, the control method comprising:

sending a control signal with a duty ratio of a preset duty ratio value P to the infrared emission device (121) so as to enable the infrared emission device (121) to emit infrared rays;

and judging whether the infrared receiving device (122) receives the infrared rays emitted by the infrared emitting device (121), and if not, judging that the cooking utensil is in a boiling state.

2. The method of controlling a cooking appliance according to claim 1, wherein after the step of determining that the cooking appliance is in a boiling state, the method further comprises:

increasing the duty ratio of the control signal until the infrared ray receiving means (122) receives the infrared ray;

the concentration of steam in the steam space is determined from the current duty cycle.

3. The method for controlling a cooking appliance according to claim 1, wherein before the step of sending a control signal with a duty ratio of a preset duty ratio value P to the infrared ray emitting device (121) to make the infrared ray emitting device (121) emit the infrared ray, the method further comprises:

sending a control signal with a duty ratio of a preset initial value to the infrared emission device (121);

judging whether the infrared receiving device (122) receives the infrared rays, if so, reducing the duty ratio of the control signal until the infrared receiving device (122) cannot receive the infrared rays, otherwise, increasing the duty ratio of the control signal until the infrared receiving device (122) receives the infrared rays;

and determining the preset duty ratio value P as the sum of the current duty ratio and a preset compensation value b.

4. The method for controlling a cooking appliance according to claim 3, wherein the preset compensation value b is in the range of 1 ≦ b ≦ 50.

5. The method of controlling a cooking appliance according to claim 1, wherein the cooking appliance includes an exhaust hole (140), and the infrared ray emitting device (121) and the infrared ray receiving device (122) are disposed at both sides of the exhaust hole (140).

6. A cooking appliance comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the cooking appliance is provided with infrared detection means comprising infrared emission means (121) for emitting infrared rays and infrared reception means (122) for receiving the infrared rays, the processor executing the program realizing the steps of:

sending a control signal with a duty ratio of a preset duty ratio value P to the infrared emission device (121) so as to enable the infrared emission device (121) to emit infrared rays;

and judging whether the infrared receiving device (122) receives the infrared rays emitted by the infrared emitting device (121), and if not, judging that the cooking utensil is in a boiling state.

7. The cooking appliance of claim 6, wherein after the step of determining that the cooking appliance is in a boiling state, execution of the program by the processor further effects the steps of:

increasing the duty ratio of the control signal until the infrared ray receiving means (122) receives the infrared ray;

the concentration of steam in the steam space is determined from the current duty cycle.

8. The cooking appliance according to claim 6, wherein before the step of sending a control signal with a duty cycle of a preset duty cycle value P to the infrared ray emitting device (121) to cause the infrared ray emitting device (121) to emit the infrared ray, the processor executing the program further realizes the steps of:

sending a control signal with a duty ratio of a preset initial value to the infrared emission device (121);

judging whether the infrared receiving device (122) receives the infrared rays, if so, reducing the duty ratio of the control signal until the infrared receiving device (122) cannot receive the infrared rays, otherwise, increasing the duty ratio of the control signal until the infrared receiving device (122) receives the infrared rays;

and determining the preset duty ratio value P as the sum of the current duty ratio and a preset compensation value b.

9. The cooking appliance of claim 6, wherein the cooking appliance includes a controller (150), the processor and the memory being configured as part of the controller (150), the cooking appliance including a detection circuit (120), the detection circuit (120) including the infrared detection device and:

a first control input (123), the first control input (123) for connecting to a first port of the controller (150);

a second control input (124), the second control input (124) for connecting to a second port of the controller (150);

a power input (125), the power input (125) for connection to a power source;

a PNP triode (126), wherein the base electrode of the PNP triode (126) is connected with the first control input end (123), and the emitter electrode of the PNP triode (126) is connected with the power supply input end (125);

a capacitor (127), wherein a first end of the capacitor (127) is connected with a collector electrode of the PNP triode (126), and a second end of the capacitor (127) is grounded;

a first resistor (128), a first terminal of the first resistor (128) being connected to the first terminal of the capacitor (127), a second terminal of the first resistor (128) being connected to the second terminal of the capacitor (127);

a second resistor (129), wherein a first end of the second resistor (129) is connected with the collector electrode of the PNP triode (126), and a second end of the second resistor (129) is connected with a first end of the infrared ray emitting device (121);

an NPN triode (130), wherein the base of the NPN triode (130) is connected with the second control input end (124), the collector of the NPN triode (130) is connected with the second end of the infrared emission device (121), and the emitter of the NPN triode (130) is grounded;

a third resistor (131), wherein a first end of the third resistor (131) is connected to the power input terminal (125), a second end of the third resistor (131) is connected to a first end of the infrared receiving device (122), and a second end of the infrared receiving device (122) is grounded;

a receiving detection terminal (132), wherein the receiving detection terminal (132) is used for connecting a detection port of the controller (150), and the receiving detection terminal (132) is connected with the second terminal of the third resistor (131).

10. The method of controlling a cooking appliance according to claim 1, wherein the cooking appliance includes an exhaust hole (140), and the infrared ray emitting device (121) and the infrared ray receiving device (122) are disposed at both sides of the exhaust hole (140).

Technical Field

The invention relates to the field of cooking appliances, in particular to a control method of a cooking appliance and the cooking appliance.

Background

A thermistor is provided in an existing cooking appliance. The cooking utensil detects the temperature of the cooking utensil through the thermistor, judges whether liquid in the cooking utensil boils or not according to the detected temperature, and then carries out relevant control to avoid overflowing. And for places with different altitudes, the temperature value at which the liquid in the cooking appliance boils differs. Thus, it may be inaccurate to determine whether the liquid in the cooking appliance is boiled or not through the detected temperature.

Therefore, the invention provides a control method of a cooking appliance and the cooking appliance, which are used for solving the problems in the prior art.

Disclosure of Invention

In this summary, concepts in a simplified form are introduced that are further described in the detailed description. 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.

The invention provides a control method of a cooking appliance, the cooking appliance is provided with an infrared detection device, the infrared detection device comprises an infrared emission device for emitting infrared rays and an infrared receiving device for receiving the infrared rays, and the control method comprises the following steps: sending a control signal with a duty ratio of a preset duty ratio value P to the infrared emission device so as to enable the infrared emission device to emit infrared rays; and judging whether the infrared receiving device receives the infrared rays emitted by the infrared emitting device, and if not, judging that the cooking utensil is in a boiling state.

According to the control method of the cooking utensil, the infrared detection device is arranged in the cooking utensil to detect the concentration of steam in the steam space through infrared rays and further judge whether liquid in the cooking utensil is boiled, so that the liquid in the cooking utensil is judged to be boiled accurately and highly reliably and is not influenced by the altitude of the place where the cooking utensil is located.

Optionally, after the step of determining that the cooking appliance is in the boiling state, the control method further comprises: increasing the duty ratio of the control signal until the infrared receiving device receives the infrared rays; the concentration of steam in the steam space is determined from the current duty cycle. Thereby, the steam concentration in the cooking appliance can be determined.

Optionally, before the step of sending a control signal with a duty ratio of a preset duty ratio value P to the infrared emitting device to make the infrared emitting device emit infrared rays, the control method further includes: sending a control signal with a duty ratio of a preset initial value to an infrared transmitting device; judging whether the infrared receiving device receives infrared rays, if so, reducing the duty ratio of the control signal until the infrared receiving device cannot receive the infrared rays, otherwise, increasing the duty ratio of the control signal until the infrared receiving device receives the infrared rays; and determining the preset duty ratio value P as the sum of the current duty ratio and the preset compensation value b.

From this, cooking utensil is cooked every time and is all redetermined preset duty ratio value P, avoids adnexed drop of water or foreign matter in the cooking utensil to block infrared propagation, and then improves the reliability of detecting.

Optionally, the preset compensation value b is in the range of 1 ≦ b ≦ 50. This can increase the degree of freedom in selecting the b value.

Optionally, the cooking appliance includes an exhaust hole, and the infrared ray emitting device and the infrared ray receiving device are disposed at both sides of the exhaust hole. Therefore, the steam at the exhaust hole can be detected, and the cooking utensil has a simple structure.

The invention also provides a cooking appliance, the cooking appliance comprises a memory, a processor and a computer program which is stored on the memory and can be run on the processor, the cooking appliance is provided with an infrared detection device, the infrared detection device comprises an infrared ray emitting device for emitting infrared rays and an infrared ray receiving device for receiving the infrared rays, and the processor executes the program to realize the following steps: sending a control signal with a duty ratio of a preset duty ratio value P to the infrared emission device so as to enable the infrared emission device to emit infrared rays; and judging whether the infrared receiving device receives the infrared rays emitted by the infrared emitting device, and if not, judging that the cooking utensil is in a boiling state.

According to the cooking appliance, the infrared detection device is arranged in the cooking appliance to detect the concentration of steam in the steam space through infrared rays and further judge whether liquid in the cooking appliance boils, so that the liquid in the cooking appliance is judged to be boiled accurately and highly reliably without being influenced by the altitude of the place where the cooking appliance is located.

Optionally, after the step of determining that the cooking appliance is in the boiling state, the processor executing the program further performs the steps of: increasing the duty ratio of the control signal until the infrared receiving device receives the infrared rays; the concentration of steam in the steam space is determined from the current duty cycle. Thereby, the steam concentration in the cooking appliance can be determined.

Optionally, before the step of sending a control signal with a duty ratio of a preset duty ratio value P to the infrared emitting device to make the infrared emitting device emit infrared rays, the control method further includes: sending a control signal with a duty ratio of a preset initial value to an infrared transmitting device; judging whether the infrared receiving device receives infrared rays, if so, reducing the duty ratio of the control signal until the infrared receiving device cannot receive the infrared rays, otherwise, increasing the duty ratio of the control signal until the infrared receiving device receives the infrared rays; and determining the preset duty ratio value P as the sum of the current duty ratio and the preset compensation value b.

From this, cooking utensil is cooked every time and is all redetermined preset duty ratio value P, avoids adnexed drop of water or foreign matter in the cooking utensil to block infrared propagation, and then improves the reliability of detecting.

Optionally, the cooking appliance comprises a controller, the processor and the memory being configured as part of the controller, the cooking appliance comprising a detection circuit comprising an infrared detection device and: the first control input end is used for connecting a first port of the controller; the second control input end is used for connecting a second port of the controller; the power input end is used for connecting a power supply; the base electrode of the PNP triode is connected with the first control input end, and the emitting electrode of the PNP triode is connected with the power supply input end; the first end of the capacitor is connected with the collector of the PNP triode, and the second end of the capacitor is grounded; the first end of the first resistor is connected with the first end of the capacitor, and the second end of the first resistor is connected with the second end of the capacitor; the first end of the second resistor is connected with the collector electrode of the PNP triode, and the second end of the second resistor is connected with the first end of the infrared emission device; the base electrode of the NPN triode is connected with the second control input end, the collector electrode of the NPN triode is connected with the second end of the infrared emission device, and the emitter electrode of the NPN triode is grounded; the first end of the third resistor is connected with the power supply input end, the second end of the third resistor is connected with the first end of the infrared receiving device, and the second end of the infrared receiving device is grounded; and the receiving detection end is used for being connected with a detection port of the controller and is connected with a second end of the third resistor. Thus, the detection circuit has a simple structure.

Optionally, the cooking appliance includes an exhaust hole, and the infrared ray emitting device and the infrared ray receiving device are disposed at both sides of the exhaust hole. Therefore, the steam at the exhaust hole can be detected, and the cooking utensil has a simple structure.

Drawings

The following drawings of the invention are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

In the drawings:

fig. 1 is a schematic flow chart illustrating a control method of a cooking appliance according to an embodiment of the present invention;

fig. 2 is another schematic flow chart of a control method of a cooking appliance according to an embodiment of the present invention;

FIG. 3 is a schematic view of the connection between the inner pan and the infrared detection device of the cooking appliance of FIG. 1; and

fig. 4 is a schematic structural diagram of a detection circuit of the cooking appliance of fig. 1.

Description of the reference numerals

110: an inner pot 120: detection circuit

121: infrared ray emitting device 122: infrared receiver

123: first control input 124: second control input terminal

125: power input terminal 126: PNP triode

127: capacitance 128: a first resistor

129: second resistance 130: NPN triode

131: third resistor 132: receiving and detecting terminal

140: exhaust hole 150: controller

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 the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular is intended to include the plural unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Exemplary embodiments according to the present invention will now be described in more detail with reference to the accompanying drawings. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. It is to be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art. In the drawings, the thicknesses of layers and regions are exaggerated for clarity, and the same elements are denoted by the same reference numerals, and thus the description thereof will be omitted.

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.

As shown in fig. 3 and 4, the cooking appliance mainly includes a pot body and a lid body. The pot body has a cylindrical inner pot accommodating portion, and the inner pot 110 can be freely put into or taken out of the inner pot accommodating portion, so that the inner pot 110 can be conveniently cleaned. The upper surface of the inner pot 110 has a circular opening for containing a material to be heated, such as rice, soup, etc., into the inner pot 110. 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 110.

As shown in fig. 3 and 4, the cooking appliance further includes a detection circuit 120 and a controller 150. The detection circuit 120 includes an infrared detection device, a first control input terminal 123, a second control input terminal 124, a power input terminal 125, a PNP transistor 126, a capacitor 127, a first resistor 128, a second resistor 129, an NPN transistor 130, a third resistor 131, and a receiving detection terminal 132.

The controller 150 includes a first port and a second port. The controller 150 may issue a first control signal through the first port. The controller 150 may adjust the duty ratio of the first control signal through a PWM (Pulse Width Modulation) technique.

The first control input 123 is connected to a first port of the controller 150. Thus, the controller 150 may send a first control signal to the detection circuit 120 via the first control input 123. The second control input 124 is for connection to a second port of the controller 150. In this way, the controller 150 may send a second control signal to the detection circuit 120 via the second control input 124.

The power input 125 is coupled to a power source to provide power to the detection circuit 120. The base of PNP transistor 126 is connected to first control input 123. The emitter of PNP transistor 126 is connected to power input 125. The collector of PNP transistor 126 is coupled to ground through capacitor 127. Thus, controller 150 sends a first control signal to the base of PNP transistor 126 to control the switching on and off of PNP transistor 126. In this way, the controller 150 can control the intensity of the infrared rays emitted by the infrared emitting device 121 by controlling the duty ratio of the first control signal and then controlling the emission frequency of the infrared emitting device 121.

A first terminal of capacitor 127 is connected to the collector of PNP transistor 126. The second terminal of capacitor 127 is connected to ground. A first terminal of the first resistor 128 is connected to a first terminal of the capacitor 127. A second terminal of the first resistor 128 is connected to a second terminal of the capacitor 127. Thus, the voltage supplied to infrared ray emitting device 121 through PNP transistor 126 can be stabilized.

A first terminal of second resistor 129 is connected to the collector of PNP transistor 126. The second end of the second resistor 129 is connected to the first end of the infrared emitting device 121. Therefore, the second resistor 129 can prevent the current between the infrared emitting device 121 and the collector of the PNP transistor 126 from being too large, and protect the infrared emitting device 121.

The base of the NPN transistor 130 is connected to the second control input 124. The collector of the NPN transistor 130 is connected to the second terminal of the infrared emitting device 121. The emitter of NPN transistor 130 is grounded. In this way, the controller 150 sends a second control signal to the base of the NPN transistor 130 to control the on/off of the NPN transistor 130, so as to determine whether the infrared emitting device 121 operates.

A first terminal of the third resistor 131 is connected to the power input terminal 125. The second end of the third resistor 131 is connected to the first end of the infrared receiving device 122. The second end of the infrared receiver 122 is grounded. Thus, the third resistor 131 can prevent the current between the first terminal of the infrared receiver 122 and the power input terminal 125 from being too large, thereby protecting the infrared receiver 122.

The infrared detection device includes an infrared receiving device 122 and an infrared emitting device 121. The infrared receiving device 122 and the infrared emitting device 121 are disposed correspondingly, so that the infrared receiving device 122 receives the infrared rays emitted by the infrared emitting device 121. The infrared ray emitting device 121 may be an infrared light emitting diode. When the circuit where the infrared light-emitting diode is located is conducted, the infrared light-emitting diode emits infrared rays. The infrared receiving device 122 may be a phototransistor. If the phototriode receives infrared rays, the first end and the second end of the phototriode are conducted, and at the moment, the circuit where the first end and the second end of the phototriode are located is conducted.

The receiving detection terminal 132 is connected to a second terminal of the third resistor 131. The receiving detection terminal 132 is connected to a detection port of the controller 150. Thus, when the first terminal and the second terminal of the infrared receiving device 122 are conducted, the voltage value of the detection signal detected by the controller 150 from the detection port is decreased, and the voltage value of the detection signal is lower than the preset voltage value. Thus, the controller 150 may collect the detection signal at the first end of the infrared ray receiving device 122 in real time through the detection port. And then whether the acquired detection signal is lower than a preset voltage value is judged, and then whether the first end and the second end of the infrared receiving device 122 are conducted is judged in real time, and then whether the infrared receiving device 122 receives infrared rays is judged. This simplifies the structure of the detection circuit 120.

In the present embodiment, the infrared ray emitting device 121 emits infrared rays to a steam space (a cooking space and a space defined by the exhaust hole 140 later). The infrared receiving device 122 is used for receiving infrared rays in the steam space. When the concentration of the steam in the steam space of the cooking appliance can block the infrared ray, the infrared ray receiving means 122 cannot receive the infrared ray emitted from the infrared ray emitting means 121. When the concentration of the vapor in the vapor space may not block the infrared ray, the infrared ray receiving device 122 may receive the infrared ray emitted from the infrared ray emitting device 121.

The concentration of steam in the steam space is low when the liquid in the cooking appliance is not boiling, and at the moment when the cooking appliance starts to boil. At this time, when the emitting power of the infrared emitting device 121 is greater than the preset power value, the steam in the steam space cannot block the infrared rays emitted by the infrared emitting device 121, and at this time, the infrared receiving device 122 can receive the infrared rays emitted by the infrared emitting device 121.

When the liquid in the cooking appliance starts to boil, steam is generated in the steam space, the concentration of the steam in the steam space increases, and when the concentration of the steam in the steam space is greater than or equal to a preset steam concentration value (the preset steam concentration value corresponds to the preset power value), the steam in the steam space can block infrared rays, and at this time, the infrared ray receiving device 122 cannot receive the infrared rays. Thus, the transmitting power of the infrared ray transmitting device 121 can be set to a preset power value to control the infrared ray transmitting device 121 to emit infrared rays. And then, whether the concentration of the steam in the steam space reaches a preset steam concentration value is determined according to whether the infrared receiving device 122 receives the infrared rays.

If the infrared receiving device 122 does not receive the infrared rays, it indicates that the steam concentration of the steam space is greater than or equal to the preset steam concentration value, and it is determined that the liquid in the cooking appliance is boiling. If the infrared ray receiving device 122 receives the infrared ray, it is determined that the steam concentration of the steam space is less than the preset steam concentration value, and it is considered that the liquid in the cooking appliance is not boiled. The preset power value may be determined experimentally.

Preferably, as shown in fig. 3, the cover is provided with a vent hole 140. The exhaust hole 140 communicates the cooking space with the external environment. The infrared ray receiving device 122 and the infrared ray emitting device 121 of the infrared ray detecting device are disposed at both sides of the exhaust hole 140 (left and right sides of the exhaust hole 140 of fig. 3). Thus, the infrared ray emitting device 121 may emit infrared rays into the exhaust hole 140. The infrared ray receiving device 122 is used for receiving the infrared ray in the exhaust hole 140. Thus, the cooking appliance has a simple structure.

As shown in fig. 1, a method for controlling a cooking appliance according to the present embodiment includes:

step 1, sending a first control signal with a duty ratio of a preset duty ratio value P to the infrared emission device 121, so that the infrared emission device 121 emits infrared rays.

The controller 150 adjusts the duty ratio of the first control signal through the PWM technique so that the duty ratio of the first control signal is the preset duty ratio value P. When the duty ratio of the first control signal is the preset duty ratio value P, the transmitting power of the infrared transmitter 121 is the preset power value. In this way, the infrared ray emitting means 121 can be controlled to emit infrared rays to the vapor space at a preset power value. The preset duty value P may be predetermined through experiments, or may be re-determined every time the cooking appliance cooks.

And step 2, judging whether the infrared receiving device 122 receives infrared rays, if not, judging that the cooking utensil is in a boiling state, and if so, judging that the cooking utensil is not in the boiling state.

When the liquid in the cooking appliance boils, steam is generated in the steam space, and the concentration of the steam in the steam space increases. When the concentration of the steam in the steam space is greater than or equal to the preset steam concentration value, the steam in the steam space may block the infrared ray, and the infrared ray receiving device 122 may not receive the infrared ray. Thus, if the infrared receiving device 122 cannot receive infrared rays, it is determined that the liquid in the cooking utensil is boiling and the cooking utensil is in a boiling state, which means that the steam in the steam space can block the infrared rays.

If the infrared receiver 122 receives infrared rays, it indicates that the steam in the steam space cannot block the infrared rays, and at this time, it is determined that the liquid in the cooking appliance is not boiling and the cooking appliance is not in a boiling state.

In this embodiment, set up infrared detection device in cooking utensil to through the steam concentration in the infrared ray detection steam space, and then judge whether the liquid in the cooking utensil boils, judge the liquid boiling accuracy in the cooking utensil from this, the reliability is high, does not receive the height above sea level influence of cooking utensil place.

In the present embodiment, after the step of determining that the cooking appliance is in the boiling state in step 2, the control method further includes:

increasing the duty ratio of the first control signal until the infrared receiving device 122 receives the infrared rays; the concentration of steam in the steam space is determined from the current duty cycle.

During boiling of the liquid in the cooking appliance, the concentration of the steam in the steam space gradually increases. And the greater the intensity of the infrared ray, the greater the concentration of the vapor through which the infrared ray can pass. The intensity of the infrared ray is proportional to the emission power of the infrared ray emitting device 121, and the greater the emission power of the infrared ray emitting device 121, the greater the intensity of the infrared ray emitted therefrom. The transmitting power of the infrared emitting device 121 is proportional to the duty ratio of the first control signal, and the larger the duty ratio of the first control signal is, the larger the transmitting power of the infrared emitting device 121 is. That is, the intensity of the infrared ray emitted by the infrared ray emitting device 121 is proportional to the duty ratio of the first control signal, and the larger the duty ratio of the first control signal is, the larger the intensity of the infrared ray reflected by the infrared ray emitting device 121 is.

In this embodiment, after it is determined that the liquid in the cooking appliance is boiled, the duty ratio of the first control signal may be gradually increased, and then the emission power of the infrared ray emitting device 121 may be gradually increased to gradually increase the intensity of the infrared ray emitted from the infrared ray emitting device 121 until the steam in the steam space may not block the infrared ray emitted from the infrared ray emitting device 121. At this time, the current emitting power of the infrared emitting device 121, and thus the intensity of the infrared currently emitted by the infrared emitting device 121, and thus the current steam concentration may be determined by the current duty ratio of the first control signal.

In the present embodiment, before step 1, a preset duty value P of the duty ratio of the first control signal needs to be determined to determine whether the liquid in the cooking appliance is boiled or not through the preset duty value P. The step of determining the preset duty value P includes steps 01, 02 and 03:

step 01, sending a first control signal with a duty ratio of a preset initial value to the infrared emitting device 121.

The controller 150 determines a preset initial value. The preset initial value may be determined experimentally or randomly. The controller 150 adjusts the duty ratio of the first control signal to a preset initial value. At this time, the intensity of the infrared rays emitted from the infrared ray emitting device 121 corresponds to a preset initial value.

And step 02, judging whether the infrared receiving device 122 receives infrared rays, if so, reducing the duty ratio of the first control signal until the infrared receiving device 122 does not receive the infrared rays, otherwise, increasing the duty ratio of the first control signal until the infrared receiving device 122 receives the infrared rays.

If the infrared receiving device 122 receives the infrared rays emitted by the infrared emitting device 121, it indicates that the steam in the steam space cannot block the infrared rays with the current intensity (the infrared intensity corresponding to the preset initial value), and the current infrared intensity is high, at this time, the duty ratio of the first control signal may be gradually reduced until the infrared receiving device 122 just cannot receive the infrared rays. At this time, the steam of the current steam space may just block the infrared ray intensity corresponding to the current duty ratio. At this time, the concentration of the steam in the current steam space corresponds to the infrared ray intensity corresponding to the current duty ratio. If the concentration of the vapor in the vapor space continues to increase without increasing the duty ratio of the first control signal, the vapor may block the infrared rays emitted from the infrared ray emitting device 121. If the concentration of the vapor in the vapor space is not increased and the duty ratio of the first control signal continues to be increased, the vapor cannot block the infrared rays emitted from the infrared ray emitting device 121.

If the infrared receiving device 122 cannot receive the infrared rays emitted by the infrared emitting device 121, it indicates that the steam in the steam space can block the infrared rays with the current intensity, and the current intensity of the infrared rays is low, at this time, the duty ratio of the first control signal can be gradually increased until the infrared receiving device 122 can just receive the infrared rays.

And step 03, determining the preset duty ratio value P as the sum of the current duty ratio and the preset compensation value b.

The sum of the current duty cycle of the first control signal and the preset compensation value b is determined as the aforementioned preset duty cycle value P. Thus, the cooking appliance re-determines the preset duty value P every time it cooks. It is prevented that the attached water drops or foreign substances in the exhaust hole 140 in the cooking appliance block the transmission of the infrared rays, thereby improving the reliability of the detection.

The preset compensation value b may be predetermined by experiments. The preset compensation value b can be set as required. Preferably, the preset compensation value b is in the range of 1 ≦ b ≦ 50. In this way, it can be ensured that the steam in the steam space can block the infrared rays emitted by the infrared ray emitting means 121 at the moment when and before the liquid in the cooking space starts to boil. This can increase the degree of freedom in selecting the b value. Further preferably, b is 8.

Specifically, the control method of the present invention is shown in fig. 2, and includes:

step S21 is executed by powering on the cooking appliance, selecting the cooking mode, and step S22 is executed.

The cooking appliance is connected to an external power source and a cooking mode, such as cooking rice, cooking porridge or cooking soup, is selected.

Step S22, setting a preset initial value, sending a first control signal to the infrared emitting device 121, making the duty ratio of the first control signal be the preset initial value, and executing step S23.

The preset initial values may be determined experimentally, e.g., experimentally predetermined at different altitudes, or randomly. The controller 150 transmits a first control signal having a duty ratio of a preset initial value to the infrared ray emitting device 121, so that the infrared ray emitting device 121 emits infrared rays having an intensity corresponding to the preset initial value to the air discharging hole 140. At this time, the cooking appliance may control the heating device to generate heat with high power to heat the food material in the inner pot 110.

Step S23, determining whether the infrared receiving device 122 receives infrared rays, if not, performing step S24, otherwise, performing step S26.

The controller 150 receives the detection signal collected by the detection terminal 132 in real time, and the controller 150 determines whether the infrared receiving device 122 receives infrared rays according to the detection signal.

Step S24, the duty ratio of the first control signal is increased, and step S25 is executed.

The duty ratio of the first control signal may be sequentially increased by a preset percentage, for example, each time the current duty ratio is increased by 5%, the preset percentage is 1%, the increased duty ratio is 6%. The preset percentage may be 2%, 3%, 8%, etc., and may be set by those skilled in the art as needed.

Step S25, determining whether the infrared receiving device 122 receives infrared rays, if yes, performing step S28, otherwise, returning to step S24.

In step S26, the duty ratio of the first control signal is decreased, and step S27 is executed.

The duty ratio of the first control signal may be reduced by a preset percentage, for example, if the current duty ratio is 10%, and the preset percentage is 1%, the reduced duty ratio is 9%. The preset percentage may be 2%, 3%, 8%, etc., and may be set by those skilled in the art as needed.

Step S27, determining whether the infrared receiving device 122 receives infrared rays, if not, executing step S28, otherwise, returning to step S26.

Step S28, determining the current duty ratio of the first control signal, and performing step S29.

Step S29, determining a preset duty ratio value P, which is the sum of the current duty ratio of the first control signal and the value b, and performing step S30.

Step S30, adjusting the duty ratio of the first control signal to a preset duty ratio value P, and executing step S31.

The controller 150 adjusts the duty ratio of the first control signal to a preset duty ratio value P so that the intensity of the infrared rays emitted from the infrared ray emitting device 121 corresponds to the preset duty ratio value P.

Step S31, determining whether the infrared receiving device 122 receives infrared rays, if yes, performing step S32, otherwise, performing step S33.

Step S32, it is determined that the liquid in the cooking utensil is not boiling.

Step S33, determining that the liquid in the cooking utensil is boiling, and step S34 is executed.

Step S34, the duty ratio of the first control signal is increased, and step S35 is executed.

In step S34, the duty ratio of the first control signal is increased in a manner substantially the same as that in step S24, which is not repeated herein.

Step S35, determining whether the infrared receiving device 122 receives infrared rays, if yes, performing step S36, otherwise, returning to step S34.

And step S36, determining the current duty ratio of the first control signal, and judging the amount of the boiled steam according to the current duty ratio.

In this embodiment, the duty ratios of the first control signals corresponding to different steam amounts one to one may be predetermined through experiments. In this way, the current duty ratio of the first control signal can be compared with the predetermined duty ratio to determine the current amount of steam.

The invention also provides a cooking appliance. The cooking appliance comprises a memory, a processor and a computer program stored on the memory and operable on the processor, the cooking appliance is provided with an infrared ray detection device, the infrared ray detection device comprises an infrared ray emitting device 121 for emitting infrared rays and an infrared ray receiving device 122 for receiving infrared rays, and the processor executes the program to realize the following steps:

sending a control signal with a duty ratio of a preset duty ratio value P to the infrared ray emitting device 121, so that the infrared ray emitting device 121 emits infrared rays;

it is determined whether infrared receiving device 122 receives infrared rays emitted from infrared emitting device 121, and if not, it is determined that the cooking utensil is in a boiling state.

In this embodiment, set up infrared detection device in cooking utensil to through the steam concentration in the infrared ray detection steam space, and then judge whether the liquid in the cooking utensil boils, judge the liquid boiling accuracy in the cooking utensil from this, the reliability is high, does not receive the height above sea level influence of cooking utensil place.

The present invention has been illustrated by the above embodiments, but it should be understood that the above embodiments are for illustrative and descriptive purposes only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that many variations and modifications may be made in accordance with the teachings of the present invention, which variations and modifications are within the scope of the present invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

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.