KR20100061801A - Electrical pressure cooker - Google Patents

Abstract

The electric pressure cooker includes an external cooker 1, an internal cooker 2, a sealing device 3, an electric heating device 4, a flexible element 5, a safety device and a control circuit for controlling the electric pressure cooker. do. The electric pressure cooker also has a capacitance sensor 8. The capacitance sensor 8 has a first electrode plate 81 and a second electrode plate 82. The electric heating device 4 is moved by pressure, and the first electrode plate 81 is moved to the second electrode in order to change the distance between the first electrode plate 81 and the second electrode plate 82. Moving with respect to the plate 82, a change signal of the capacitor is then generated and input into the control circuit. The control circuit processes the signal and controls the electric pressure cooker based thereon.

Description

ELECTRICAL PRESSURE COOKER

FIELD OF THE INVENTION The present invention relates to pressure cookers, and more particularly to electric pressure cookers.

At present, the electric pressure cooker replaces the existing old-fashioned pressure cooker due to its energy saving and fast and convenient advantages, and the electric pressure cooker is a family kitchen daily one of the houshold appliances. There are three main types of electric pressure cookers available on the market in terms of pressure control and regulation.

The first form comprises a flashing switch set at the bottom of an external cooker of the electric pressure cooker and a heating plate set for contacting a feeler lever to turn the flashing switch on and off. plate). The heating device is operated and separated by using a move-up and-down in response to a change in the internal pressure when the internal cooker is operated. When the electric pressure cooker is activated, the pressure in the cooker is increased and the heating plate moves downward. When the pressure in the cooker is increased to a predetermined value, the heating plate moves downward and the filler lever is in proximity to the flashing switch. Then, the flashing switch is turned off and the heating device stops operating; When the pressure is reduced, the heating plate moves upwards and the pillar lever is spaced apart from the flashing switch. The flashing switch is closed and the heating device starts to operate. Thus, the object for controlling the internal pressure of the pressure cooker is achieved.

For example, Chinese Patent No. 91100026.7, issued June 23, 1993, describes a fully sealed automatic electric pressure home cooker. Rigid and flexible arms on a vertical column firmly pressurize the lid and the cooker, which achieves sealing with a sealing ring, which combines the flexibility of a safe, convenient and fully sealed electric cooker Provide a reasonable structure of the cap (flexible combined cap). The flexible arm drives an adjustable flashing switch to control the heating state of the electric heating panel between the bottom of the cooker and the flexible arm, whereby the adjustment and automatic control of the pressure in the electric cooker is achieved and fully An ideal model of a sealed electric cooker is formed.

In another example, Chinese Utility Model 20042094674.4, issued January 18, 2006, an automatic voltage controlled electric pressure cooker is described which includes a cover, a shell, an external cooker, a base, a heating plate, It includes an internal cooker, an elastomer and a pressure switch set on the heating plate. An elastomeric connection is established between the heating plate and the bottom of the outer cooker. The heating plate also has a catch bar through which deformation of the elastic body can actuate the pressure switch. At the bottom of the outer cooker a bearing face which is connected with a heating plate and flexible support feet is set on the elastic body. And at least one pair of said elastic bodies set between the heating plate and the bottom of the outer cooker is provided. As the pressure changes during the operation of the electric pressure cooker, the heating plate moves up and down so that the catch bar starts operating the pressure switch and also controls the operation of the pressure cooker.

This type of electric pressure cooker has disadvantages due to un-adjustable pressure and fixed pressure values. When cooking different foods, this is done by simply setting the time to achieve different dishes. However, different foods always require different pressure values to achieve the best cooking effect. For example, the best cooking pressure values for beef, ribs, porridge are different. If only this time is adjusted, the food being cooked is inferior in taste and retained nutrition.

The second form features a temperature sensor or a pressure sensor set in the cover of the electric pressure cooker and on the inner cooker for sensing temperature and pressure changes in the cooker and for inputting signals into circuits for detection and control. When the pressure in the cooker reaches a preset pressure, it stops operation and resumes operation when the pressure drops.

In the plan, the pressure sensor or temperature sensor must be in direct contact with a cavity in the cooker in order to sense the pressure or temperature in the internal cooker, which makes the installation location very limited. Since the internal cooker is frequently required to be cleaned and there is a problem in wiring connection and signal transmission, it cannot be located directly in the internal cooker. It is often installed on the cover. When the porridge or other food is cooked in an internal cooker, many bubbles or small hard objects will cover or damage the sensor, affecting the sensing sensivity of the sensor, so this works normally You will not be able to.

In the method of using the temperature sensor, it is necessary to first collect a temperature in the cooker and then convert the temperature into a pressure value related to the temperature. This conversion has a conversion table with general meaning by experiment. See the following table:

Many experiments have concluded that temperature and pressure have some correspondence. From the following table, it can be seen that when the temperature of the water exceeds 100 ° C, the pressure increases by 5 kPa every time the temperature increases by 1 degree.

Temperature ℃ 80 90 100 101 102 103 104 105 106 Pressure Kpa 0 0 0 5 10 15 20 25 30 Temperature ℃ 107 108 109 110 111 112 113 114 115 Pressure Kpa 35 40 45 50 55 60 65 70 75

Note: Ambient temperature is 25 ° C, 1 standard atmospheric pressure.

The temperature and pressure conversions shown in the table above are obtained through numerous experiments when the ambient temperature is 25 ° C. and the ambient pressure is 1 standard atmospheric pressure. When the ambient temperature is changed or when the ambient atmospheric pressure is not the standard atmospheric pressure due to different regions, the corresponding conversion table is not accurate. In addition, for the temperature sensor, due to the change in weight, density, and composition included of the food, the temperature requirements will be different and the conversion of temperature and pressure will also be affected. Thus, if the ambient temperature, the ambient atmospheric pressure and the food are different, the pressure values associated with the temperature are entirely different. As a direct result, detection errors occur and the accuracy and sensitivity fall considerably, which affects the effective control of pressure. If the detection and control are lost in accuracy, this increases the risk factor in using the electric pressure cooker and thus is unsafe for the user.

On the other hand, the production cost due to the use of pressure or temperature sensors becomes higher, which is disadvantageous for the spread of electric pressure cookers.

A third form is characterized by an inductance coil set in the cell pressure cooker. The inductance value of the coil is changed by the displacement generated by the pressure change of the internal cooker. The changed inductance value is extracted for determination and processing to control the pressure of the cooker.

Most of the schemes set an inductance coil under the outer cooker and a pillar lever below the bottom of the inner cooker or heating plate. When the pressure of the inner cooker of the electric pressure cooker changes, the inner cooker or the heating plate moves up and down, and drives the filler lever inside or outside the inductance coil to change the inductance value. Then, the determination and processing are executed according to the changed inductance value to control the operation of the electric pressure cooker.

Since the characteristics of the inductance coil are unstable and easily disturbed by external environments such as temperature, electromagnetic, etc., pressure detection in the cooker is easily error-prone and also affects the stability of the pressure control. However, once the pressure detection of the electric pressure cooker suffers from any error, instability and ease of interference which can be hindered by environmental factors, it becomes very easy for the actual operating pressure of the cooker to become very high, resulting in poor stability and Low detected pressure for the same reason may create a risk of cooker explosion. This is very dangerous for the user. Therefore, for this solution, it is very important to increase the stability and increase the ability to prevent the disturbance of external environmental elements such as temperature, electromagnetic, etc., which is directly related to the safe use of the electric pressure cooker and the user safety. Is related.

In addition, the cost of using the inductance coil is relatively high.

Chinese Patent No.91100026.7 China Utility Model No.20042094674.4

In order to solve the above-mentioned problems of the prior art, an object of the present invention is to provide an electric pressure cooker which can detect and control the pressure in real time, regulate the pressure constantly, and select different pressures and different food operating times. To provide.

The main technical solution adopted in the present invention is the following electric pressure cooker. The electric pressure cooker includes an external cooker, an internal cooker located in the external cooker, a sealing device for sealing the internal cooker, an electric heating device used to heat the internal cooker and compatible with the internal cooker, the A flexible element and a safety device set between the electric heating device and the external cooker for resetting the internal cooker, and a control circuit for controlling the electric heating device. The control circuit includes a capacitance sensor, a signal processing circuit, and a signal control output circuit. The capacitance sensor includes a first electrode plate and a second electrode plate. Signal sampling ends of the first electrode plate and the second electrode plate are respectively set. The signal sampling end is connected with the signal receiving end of the signal processing circuit. The capacitance sensor is matched with the electric pressure cooker, detects a displacement change caused by the pressure change of the electric pressure cooker, converts the displacement change into a changing signal, and inputs it to the signal processing circuit. The signal output end of the signal processing circuit is connected to the signal receiving end of the signal control output circuit. The signal processing circuit processes the received capacity signal and outputs the processed signal to the signal control output circuit. According to the received processing signal, the signal control output circuit controls the circuit to control the operation of the electric heating device.

In addition, the present invention adopts the following technical solution: The control circuit also includes a compensation capacitor, wherein the capacitance value of the temperature and electromagnetic disturbances, and the capacitance value of the capacitance sensor are Occur and change at the same time.

The compensation capacitor comprises two electrode plates, one of which is the first or second electrode plate of the capacitance sensor.

The first electrode plate and the second electrode plate are related to each other. The internal cooker is under pressure to generate a displacement change, and then directly or indirectly drives the first electrode plate to move relative to or behind the second electrode plate, which causes the first capacitance plate to generate the changed capacitance signal. The distance to the second electrode plate 82 is reduced or increased.

A displacement transferring piece is set between the electric heating device and the first electrode plate. The internal cooker receives a pressure change to generate a displacement change, and moves the electric heating device, and the electric heating device moves the first electrode plate by the displacement transfer piece.

The displacement transfer piece is a screw, there is a screw hole corresponding to the screw in the electric heating device and / or the first electrode plate, and the first electrode plate is connected with the screw in the electric heating device by the screw. .

The displacement transfer piece is a mandrel. There is an elastomer capable of moving the first electrode plate between the first electrode plate and the second electrode plate. One end of the mandrel is connected to the bottom of the electric heating device or the first electrode plate, and the other end is attached to the bottom of the first electrode or the electric heating device.

The second electrode plate is installed on the bottom of the outer cooker or on the sidewall of the outer cooker with a bracket.

There is a leverage device between the displacement transfer piece and the first electrode plate. The displacement transfer piece drives the short arm of the lever device and the long arm drives the first electrode plate.

The first electrode plate and the second electrode plate are set between the electric heating device and the bottom of the external cooker, are also located on the same plane and are respectively associated with the electric heating device. The electric heating device moves due to the displacement change of the internal cooker, and then changes the medium in the electric field generated by the first electrode plate and the second electrode plate.

The first electrode plate and the second electrode plate are related to each other. As the pressure of the internal cooker changes, the displacement changes to directly or indirectly move the first electrode plate and / or the second electrode plate. The movement changes the effective area between the first electrode plate and the second electrode plate in order to generate a changeable capacitance signal.

A displacement guide rod is provided between the electric heating device and the first electrode plate. Both ends of the displacement guide rod are respectively connected with the electric heating device and / or the first electrode plate. The internal cooker is pressurized to generate a displacement change and to move the electrical heating device. The electric heating device moves the first electrode plate by the displacement guide rod. The second electrode plate is provided on the sidewall of the outer cooker by the bottom of the outer cooker or by a bracket.

There is a lever device between the displacement guide rod and the first electrode plate. The displacement guide rod drives the short arm of the lever device and the long arm drives the first electrode plate.

Advantages of the present invention are as follows.

(1) The present invention employs a capacitance sensor, uses a change in the pressure or heating plate of the internal cooker to generate displacement, collects the changed capacitance value, and controls the capacitance value to control the operation of the electric pressure cooker. To process. The capacitance sensor adopted in the present invention changes the capacitance value in real time based on the pressure change, and according to the capacitance value having the real time change, the pressure is set by the user. Set benchmarking capacitance to determine if it exceeds. When setting the benchmark capacitance, the user can adjust the range of pressure and operating time in real time based on the actual food to be cooked. The use of existing advanced CPU control techniques can detect and control multi-parameter information, such as pressure and time. This may consist of a control mechanism similar to the "one-key-pass" of the induction cooker and may also correspond to different foods to achieve a constantly adjustable pressure. Different pressures are set for different foods to better ensure food fit and nutrition.

(2) The capacitance sensor has good stability and high sensitivity precision with a reliable capacitance signal, which produces higher precision and accuracy in the control of the electric pressure cooker.

(3) The electrode plate of the capacitance sensor in the present invention is connected to an internal cooker or a heating plate. The capacitance change is made using a pressure change of the internal cooker or a displacement caused by the heating plate. The displacement is converted into a capacitance value in order to detect the pressure in the cooker without setting it as a pressure sensor or a temperature sensor to the internal cooker. The detection is reliable and useful for extracting signals without being disturbed by the food cooked in the internal cooker.

(4) On the basis of the capacitance sensor, the present invention is provided with a compensation capacitor capable of detecting in real time the change in capacitance caused by the temperature and electromagnetic interference. By calculating circuit processing, the compensation capacitor can compensate and modify the measurement of the capacitance sensor so that the processed and calculated measurements can more accurately reflect the displacement change and are less affected by environmental factors. This improves the accuracy and stability of the pressure control.

(5) In the present invention, a lever device is provided between an electrode plate of a capacitance sensor and an internal cooker or a heating plate. The amplification principle of the lever is used to drive the distance between the electrodes of the capacitance sensor, or the capacitance electrode plate is used to increase the area of the electrode plate in order to enlarge the capacitance value many times and improve the sensitivity of the detection. It is set to multilayer.

(6) The capacitance sensor is inexpensive and simple in structure, which is easy for batch production.

(7) A screw connection is adopted for the capacitance sensor and the heating plate of the present invention. The distance between the electrode plates can be controlled by adjusting the screw to achieve a small adjustment of the distance between the electrode plates of the capacitance sensor so as to improve the sensitivity and accuracy of the capacitance sensor.

1 is an overall cross-sectional view of Embodiment 1 of the present invention, in which a flexible plate drives an electrode plate of a capacitance sensor in order to change the distance between electrode plates, and the capacitance sensor and the compensation capacitor are in a technical form. It is a figure which shows a solution.
2 and 3 are two overall cross-sectional views of Embodiment 2 of the present invention having two kinds of realization structures, in which a heating device drives the electrode plate of the capacitance sensor to change the distance between the electrode plates, The capacitance sensor and the compensation capacitor are diagrams showing technical solutions set on the brackets.
4 is an overall cross-sectional view of Embodiment 3 of the present invention, in which the heating device drives the electrode plate of the capacitance sensor to change the distance between the electrode plates, and the capacitance sensor and the compensation capacitor are set separately. It is a figure.
FIG. 5 is an overall sectional view of Embodiment 4 of the present invention, wherein a heating device drives an electrode plate of a capacitance sensor to change the distance between electrode plates by a leverage institution, and the capacitance sensor and the compensation capacitor are combined It is a figure which shows the technical solution in form.
6 and 7 are two overall cross-sectional views of Embodiment 5 of the present invention having two kinds of realization structures, in which a heating device drives the electrode plate of the capacitance sensor to change the area between the electrode plates, and the capacitance sensor And the compensation capacitor is a diagram showing a technical solution in a complex form.
FIG. 8 is an overall cross-sectional view of Embodiment 6 of the present invention, in which a heating device drives an electrode plate of a capacitance sensor to change an area between electrode plates by a lever mechanism, and the capacitance sensor and the compensation capacitor are in a composite form. It is a figure which shows the plan.
FIG. 9 is an overall sectional view of Embodiment 7 of the present invention, in which the heating device changes the medium of an electric field formed between two electrode plates of a capacitance sensor by vertical displacement.
10 is a structural cross sectional view of the present invention using multiple sets of capacitance sensors.
11 is a bottom view of the lid of the present invention.
12 is a cross-sectional view along the line AA of FIG. 11 showing the structure of the pressure limiting valve.
13 is a circuit block diagram of a control circuit of the present invention.
FIG. 14 is a detailed circuit diagram of FIG. 13.

The invention is explained in more detail according to the drawings as follows.

In the drawings, the reference numbers attached to the parts correspond to the following:

External cooker is 1, internal cooker is 2, sealing device is 3, electric heating device is 4, flexible element is 5, safety device is 6, control panel is 7, capacitance sensor is 8, first electrode plate is 81, second The electrode plate is 82, the compensation capacitor is 9, the first electrode plate is 91, the second electrode plate is 92, the displacement transferring piece is 10, the elastic body is 11, the bracket is 12, the lever device is 13, the displacement guide rod Is 14, cover is 15, handle is 16, shell is 17 and compression spring is 18.

As shown in FIGS. 1 to 14, the electric pressure cooker provided for the present invention seals the outer cooker 1, the inner cooker 2 located in the outer cooker 1, and the inner cooker 2. To reset the sealing device 3, the electric heating device 4 used to heat the inner cooker 2 by being compatible with the inner cooker 2, and the inner cooker 2. To include a flexible element 5 and a safety device 6 set between the electric heating device 4 and the external cooker 1, and a control circuit for controlling the operation of the electric heating device 4. The control circuit includes a capacitance sensor 8, a signal processing circuit 71, and a signal control output circuit 72.

The capacitance sensor 8 includes a first electrode plate 81 and a second electrode plate 82 which are respectively provided with a signal collection end. The signal collecting end is connected to the signal receiving end of the signal processing circuit 71. The capacitance sensor 8 and the electric pressure cooker detect a displacement change caused by the pressure change of the electric pressure cooker, convert the displacement change into a changed signal of the capacitance and input it to the signal processing circuit 71. Match each other. The signal output end of the signal processing circuit 71 is connected to the signal receiving end of the signal control output circuit 72. The signal processing circuit 71 processes the received capacitance signal and outputs the processed signal to the signal control output circuit 72. The signal control output circuit 72 controls the circuit according to the received processing signal to control the operation of the electric heating device 4.

In the present invention, the control circuit also comprises a compensation capacitor 9, the capacitance of which occurs and changes simultaneously with the capacitance of the capacitance sensor 8 when disturbed by temperature and electromagnetic. The compensation capacitor 9 comprises two electrode plates, one of which is the first electrode plate 81 or the second electrode plate 82 of the capacitance sensor. On the basis of the capacitance sensor 8, the invention is provided with a compensation capacitance 9 which can detect in real time the change in capacitance caused by temperature and electromagnetic disturbance elements. By processing and calculating the circuit, this can compensate and correct the measurement of the capacitance sensor 8, so that the measurement and calculation by the process can more accurately reflect the change in displacement, and less by environmental factors. Will be affected, which will improve the accuracy and stability of the pressure control.

The first electrode plate 81 and the second electrode plate 82 of the capacitance sensor are related to each other. A change in displacement occurs due to a change in pressure of the internal cooker 2, which causes the first electrode plate 81 to move relative to or behind the second electrode plate 82, directly or indirectly, so that the second electrode plate Reduce or increase the distance to 82 to generate a changed capacitance signal. The displacement transfer piece 10 is provided between the electric heating device 4 and the first electrode plate 81. A change in displacement occurs due to a change in pressure of the internal cooker 2 and moves the electric heating device 4. The electric heating device 4 moves the first electrode plate 81 by the displacement transfer piece 10.

In the method of causing displacement change due to the pressure change of the internal cooker 2, the first electrode plate 81 is moved directly to or behind the second electrode plate 82. The first electrode plate 81 is set as a mandrel in direct contact with the bottom of the internal cooker 2 via the heating device 4. When the inner cooker 2 moves up and down due to pressure, the first electrode plate 81 is moved up and down through the mandrel. It is relatively difficult to realize such a structure in practical production and manufacturing. In addition, practically no electric pressure cooker is produced to adopt this structure. As a result, the present invention only describes the achievement of the above scheme in the theoretical language herein. However, since no substantial meaning exists in practical production, additional drawings will not be provided for explanation.

In each embodiment provided in the present invention, the electric heating device 4 is a cast aluminum heating plate or an electromagnetic coil module; The sealing device 3 is a “herringbone” sealing ring; The safety device 6 comprises a pressure limiting valve as shown in FIGS. 5 and 6 or a counterpart of the same construction. The safety device 6 as described above has an action of preventing explosion by cutting off electricity or releasing air when the pressure of the cooker reaches a dangerous value during the operation of the electric pressure cooker. An external circle of the cover 15 is sealed with the outer cooker 1 through a tooth buckle design of the cooker, and the inner circle may seal the inner cooker 2. To the inner cooker 2 via the herring barbed sealing ring.

The match included in the present invention between the lid 15 and the inner cooker 2 and between the lid 15 and the outer cooker 1 may be a flip structure in addition to the rotary structure described above. have.

In Embodiment 1 provided in the present invention (as shown in FIG. 1), the inner cooker 2 is attached in close proximity to the heating plate 4. The flexible plate, ie flexible element 5, is arranged below the heating plate 4. Both ends of the flexible plate 5 are fastened on the side walls of the outer cooker 1. The capacitance sensor 8 and the compensation capacitor 9, which are composite in this embodiment, are aligned between the outer cooker 1 and the shell 17 and at the bottom of the shell 17. The second electrode plate 82 of the capacitance sensor 8 shares the same electrode plate as the second electrode plate 92 of the compensation capacitor 9. The first electrode plate 81 of the capacitance sensor 8 is connected with the flexible element 5 via the displacement transfer piece 10. In this implementation, the displacement transfer piece 10 is a link bar. The inner cooker 2 is driven to move up and down by pressure. The flexible element 5 moves down under the drive of a heating plate 4 connected in close proximity to the inner cooker 2 and moves the first electrode plate 81 relative to the second electrode plate 82. To transfer the displacement of the first electrode plate (81) through the displacement transfer piece (10) to make it possible; Therefore, a capacitance change is generated and input to the control panel 7.

In Embodiment 2 of the present invention, the displacement transfer piece 10 is a screw; There is a screw hole corresponding to the screw in the electric heating device 4 and / or the first electrode plate 81.

2 is a configuration diagram of Embodiment 2 of the present invention. The flexible element 5 is a U-shaped clip which is fastened between the outer cooker 1 and the inner cooker 2. The capacitance sensor 8 and the compensation capacitor 9 are complex and are formed of assembly parts arranged in a shell. The shell has a threaded rod and engages a screw of the bracket 12 arranged on the side wall of the outer cooker 1. The complex form described above means that the second electrode plate 82 of the capacitance sensor 8 allocates the same electrode plate 92 as the second electrode plate 92 of the compensation capacitor 9, The first electrode plate 91 of the compensation capacitor 9 is fixed relative to the second electrode plate 92 such that the distance between the first electrode plate 91 and the second electrode plate 92 cannot be changed. . One end of the displacement transfer piece (ie, screw) 10 is fixedly connected to the first electrode plate 81, and the other end is connected to a screw on the heating plate 4. The heating plate 4 is influenced by the vertical movement of the displacement transfer piece 10, the first electrode 81 is the second electrode plate 2 to generate a capacitance change input to the control circuit. To move). The compensation capacitor 9 acts as a compensation capacitance sensor in capacitance signal deviation resulting from temperature and electromagnetic disturbances.

In this embodiment, the first electrode plate 81 is connected with the displacement transfer piece 10, and thus one end of the displacement transfer piece is connected with a screw on the heating plate 4. In practical use, the main distance between the first electrode plate 81 and the second electrode plate 82 determines the depth of the displacement transfer piece 10 (i.e., screw) inserted into the screw hole to improve the observation accuracy. It can be adjusted slightly by controlling. This embodiment has good flexibility and contingency.

3 is another structure of Embodiment 2 of the present invention. The capacitance sensor 8 and the compensation capacitor 9 connected together in FIG. 2 are inverted 180 degrees. In this case, the displacement transfer piece 10 can be regarded as a shell of the capacitance sensor and the compensation capacitor connected together. And, the connection with the bracket 12 is made through the screw aligned on the electrode plate in FIG. Next, the two electrode plates fastened to the shell and aligned thereon are the first electrode plate 91 of the compensation capacitor 9 and the first electrode plate 81 of the capacitor sensor 8, respectively. . In addition, the first electrode plate 81 allocates the same electrode plate as the second electrode plate 92. The movable electrode plate aligned with the bottom of the shell is the second electrode plate 82 of the capacitance sensor 8.

When the heating plate 4 is driven to move the shell of the capacitor sensor 8 and the compensation capacitor 9 up and down, the first electrode plate 91 and the second electrode plate of the compensation capacitor 9 92 moves up and down at the same time, but the distance between them is fixed. The first electrode plate 81, which allocates the same electrode plate as the second electrode plate 92, moves relative to the second electrode plate 82, thereby allowing the first electrode plate 81 and the second electrode plate to move. The distance between the 82 will change. Then, the change in displacement causes a change in capacitance. This approach has the main advantage that a small adjustment of the screw position occurs on the bracket of the outer cooker in order to provide the convenience of adjustment.

The displacement transfer piece 10 is a mandrel. An elastic body 11 is provided between the first electrode plate 81 and the second electrode plate 82 to allow the movement of the first electrode plate 81. One end of the mandrel is connected to the bottom of the electric heating device 4 or the first electrode plate 81. The other end is fixed to the bottom of the first electrode plate 81 or the electric heating device 4.

In the present invention, the capacitor sensor 8 and the compensation capacitor 9 can be fixed on the side wall of the outer cooker 1 via the L-shaped bracket 12 or on the bottom of the outer cooker 1 via the U-shaped bracket. have.

In embodiment 3 (as shown in FIG. 4) of the invention, the compensation capacitor 9 is arranged separately from the bracket 12 on the outer cooker 1. The elastic body 11 is an S-shaped clip, and is aligned between the first electrode plate 81 and the second electrode plate 82. One end of the mandrel 10 is connected to the first electrode plate 81 of the capacitance sensor 8, and the other end is attached to the bottom of the heating plate 4. During operation, the heating plate moves downward to drive the mandrel 10 attached to the heating plate 4, and the mandrel 10 also moves the first electrode plate 81 downward so that the S-shaped clip ( 11) to pressurize. When the heating plate 4 moves upward, the pressed S-shaped clip 11 returns to its original shape, and the first electrode plate 81 is pushed upward, so that the mandrel 10 causes the heating plate 4 to move. It is kept to be attached to the bottom of the), and thus completes the vertical movement to generate a capacitance change signal input to the control panel (7). Separately aligned compensation capacitors 9 compensate the capacitance sensor 8 for capacitance deviations resulting from temperature and electromagnetic disturbances.

In this way, the compensation capacitor 9 is arranged separately from the electric pressure cooker. Obviously, the compensation capacitor 9 can be arranged or separated separately from the capacitance sensor 8 in another way provided in the present invention.

In embodiment 4 (as shown in FIG. 5) of the present invention, the capacitance sensor 8 and the compensation capacitor 9 are in a composite form, aligned with the bracket 12 on the side wall of the outer cooker 1. do. The lever device 13 is aligned between the displacement transfer piece 10 and the first electrode plate 81. One end of the displacement transfer piece 10 is connected to the bottom of the heating plate 4, and the other end is geared with the short arm end of the lever device 13. The long arm end of the lever device 13 is linked with the first electrode plate 81. When the heating plate 4 moves up and down, the displacement transfer piece 10 moves the lever device 13, and the short arm end moves the long arm of the lever. The long arm then moves the first electrode plate 81 up and down again. The amplification principle of the lever is used to magnify the capacitance many times to drive the distance between the capacitor sensor plates to improve the inspection sensitivity.

The solution uses the lever principle to multiply the displacement many times. Obviously, the structure as shown in Fig. 10 also allows the electrode plate of the capacitance sensor to be multi-layered or multi-grouped, in order to realize the multiple magnification of the capacitance and improve the inspection sensitivity, as well as increase the area between the electrode plates. It may be the same as that provided in.

In Embodiment 5 of the present invention, the first electrode plate 81 and the second electrode plate 82 are related to each other. The displacement changes as the pressure in the inner cooker 2 changes so that the first electrode plate 81 and / or the second electrode plate 82 can be moved directly or indirectly. The movement changes the effective area between the first electrode plate 81 and the second electrode plate 82 so as to generate a variable capacitance signal.

6 is a structural diagram of Embodiment 5 of the present invention. The capacitance sensor 8 and the compensation capacitor 9 are of a complex shape and are aligned with the bracket 12 on the side wall of the outer cooker 1. The electrode plates of the capacitance sensor 8 and the compensation capacitor 9 are perpendicular to each other. The displacement guide rod 14 is aligned between the heating plate 4 and the first electrode plate 81. Both ends of the displacement guide rod 14 are connected to the heating plate 4 and the first electrode plate 81, respectively. As the pressure in the inner cooker 2 changes and the heating plate 4 moves, a displacement change occurs. The heating plate 4 moves the first electrode plate 81 up and down through the displacement guide rod 14, which is an effective area between the first electrode plate 81 and the second electrode plate 82. Is changed to generate a capacity change signal input to the control panel 7.

7 is another structural diagram of Embodiment 5 of the present invention. In the structure shown, one end of the displacement guide rod 14 is connected with a screw on the bottom of the heating plate 4, and the other end is attached to the side wall of the first electrode plate 81 of the capacitance sensor 8. do. The compression spring 18 bears against the other side wall of the first electrode plate 81, the other end of which is fixed to the shell of the capacitance sensor 8 and the compensation capacitor 9 which are connected to each other. When moving downwards, the heating plate 4 is driven to push the displacement guide rod 14 downward. The displacement guide rod 14 moves the first electrode plate 81 attached to the rod 14 downward and also presses the compression spring 18. When the heating plate 4 returns upward, the compression spring 18 also returns to its original position, allowing the first electrode plate 81 to continuously contact the displacement guide rod 14. The first electrode plate 81 is pushed upward in order to complete the vertical movement, thereby generating a changing signal of the capacitor input to the control panel 7.

In Embodiment 6 (as shown in FIG. 8) of the present invention, the lever device 13 is aligned between the displacement guide rod 14 and the first electrode plate 81. One end of the displacement guide rod 14 is connected to the bottom of the heating plate 4, and the other end is connected to the short arm end of the lever device 13. The long arm end of the lever device 13 is connected with the first electrode plate 81. When moving downwards and upwards, the heating plate 4 moves the short arm end of the lever device 13, and the short arm end drives the long arm through the lever 14. The long arm end moves the first electrode plate 81 up and down again. In order to vary the distance between the capacitance sensor plates and to enlarge the capacitance many times, the amplification principle of the lever is used to improve the inspection sensitivity.

In Embodiment 7 (as shown in FIG. 9) of the present invention, the first electrode plate 81 and the second electrode plate 82 are aligned between the heating plate 4 and the bottom of the outer cooker 1. And are located at the same level and correspond to the heating plate 4, respectively. The heating plate 4 is moved when the displacement of the internal cooker 2 changes, thereby changing the electric field medium generated by the first electrode plate 81 and the second electrode plate 82, and the control panel ( 7) generates a change in capacitance input.

In each embodiment of the present invention (as shown in FIGS. 13 and 14), the control circuit of the control panel 7 includes a signal processing circuit 71 and a signal control output circuit 72. The signal processing circuit 71 includes an oscillatory circuit 711 and a microprocessor 712. The signal control output circuit 72 is a relay control circuit or a controllable silicon circuit.

The capacitance signal collected by the capacitance sensor 8 and the compensation capacitor 9 is input to the vibration circuit 711 of the signal processing circuit 71, and the vibration signal of a predetermined frequency is output to the microprocessor 712. . The vibration signal forms an output control signal of the sensor after adjustment of a self-adaptive algorithm in the microprocessor 712, and the output control signal controls the operation of the heating plate according to the received signal. To the signal control output circuit 72. When the electric pressure cooker is operated, the signal control output circuit 72 continuously executes the inspection, controls the operation of the electric pressure cooker, and forms a closed-loop control system.

When the signal control output circuit 712 adopts a controllable silicon circuit, the flow angle of the controllable silica is adjusted in accordance with the signal input, and the controllable silica is configured to heat the heating power of the heating plate 4. When this increases continuously, it is used to adjust the pressure and output so as to continuously reduce the heating power of the heating plate 4 until the circuit is interrupted or closed.

1: outer cooker, 2: inner cooker, 3: sealing device, 5: flexible element, 6: safety device, 7: control panel, 8: capacitance sensor, 81: first electrode plate, 82: second electrode plate, 9 : Compensation capacitor, 91: first electrode plate, 92: second electrode plate, 10: displacement transfer piece, 11: elastic body, 12: bracket, 13: lever device, 14: displacement guide rod, 15: cover, 16: handle , 17: shell, 18: compression spring

Claims (13)

Used to heat the outer cooker 1, the inner cooker 2 located in the outer cooker 1, the sealing device 3 used to seal the inner cooker 2, the inner cooker 2 Electric heating device 4 fitted to the inner cooker 2, flexible element 5 and safety set between the electric heating device 4 and the outer cooker 1 for resetting the inner cooker 2. In an electric pressure cooker comprising a device (6) and a control circuit for controlling the operation of the electric heating device (4),
The control circuit comprises a capacitance sensor (8), a signal processing circuit (71), and a signal control output circuit (72);
The capacitance sensor (8) comprises the first electrode plate (81) and the second electrode plate (82) set respectively with the signal collection end; The signal collection end is connected to the signal receiving end of the signal processing circuit 71; The capacitance sensor 8 and the electric pressure cooker detect a displacement change caused by the pressure change of the electric pressure cooker, convert the displacement change into a changed signal of capacitance, and thereby convert it into the signal processing circuit 71. Match each other for input into;
The signal output end of the signal processing circuit 71 is connected to the signal receiving end of the signal control output circuit 72, and the signal processing circuit 71 processes the received capacitance signal and sends the processed signal to the Output to a signal control output circuit 72;
And the signal control output circuit (72) controls the circuit according to the received control signal to control the operation of the electric heating device (4). The method according to claim 1,
The control circuit also includes a compensation capacitor (9), wherein the capacitance of the compensation capacitor occurs and changes simultaneously with the capacitance of the capacitance sensor when disturbed by temperature and electromagnetic. The method according to claim 2,
The compensation capacitor (9) comprises two electrode plates, one of which is the first electrode plate (81) or the second electrode plate (82) of the capacitance sensor. The method according to any one of claims 1 to 3,
The first electrode plate 81 and the second electrode plate 82 correspond to each other, and a displacement change occurs due to a pressure change of the internal cooker 2, and this causes the first electrode plate 81 to be directly or Indirectly moving with respect to or behind the second electrode plate (82) and reducing or increasing the distance to the second electrode plate (82) to generate the changed capacitance signal. The method according to claim 4,
A displacement transfer piece 10 is provided between the electric heating device 4 and the first electrode plate 81, and a displacement change occurs in response to a pressure change of the internal cooker 2, thereby causing the electric heating device ( 4), wherein the electric heating device (4) moves the first electrode plate (81) by the displacement transfer piece (10). The method according to claim 5,
The displacement transfer piece 10 is a screw, and there is a screw hole corresponding to the screw in the electric heating device 4 and / or the first electrode plate 81, and the first electrode plate 81 is the screw. Electric pressure cooker, characterized in that it is connected to the screw in the electric heating device (4). The method according to claim 5,
The displacement transfer piece 10 is a mandrel, and there is an elastic body 11 capable of moving the first electrode plate 81 between the first electrode plate 81 and the second electrode plate 82. One end of the mandrel is connected to the bottom of the electric heating device 4 or the first electrode plate 81, and the other end is attached to the bottom of the first electrode 81 or the electric heating device 4. Featuring an electric pressure cooker. The method according to claim 4,
The second electrode plate (82) is installed at the bottom of the outer cooker (1) or on a side wall of the outer cooker (1) with a bracket (12). The method according to claim 5,
There is a lever device 13 between the displacement transfer piece 10 and the first electrode plate 81, the displacement transfer piece 10 drives the short arm of the lever device 13 and the long arm An electric pressure cooker, characterized in that for driving the first electrode plate (81). The method according to any one of claims 1 to 3,
The first electrode plate 81 and the second electrode plate 82 are set between the electric heating device 4 and the bottom of the external cooker 1 and are also located on the same surface and are arranged on the electric heating device 4. Respectively, the electric heating device 4 moves due to the change of displacement of the internal cooker, and then the medium in the electric field generated by the first electrode plate 81 and the second electrode plate 82. Electric pressure cooker, characterized in that for changing. The method according to any one of claims 1 to 3,
The first electrode plate 81 and the second electrode plate 82 correspond to each other, and a displacement change occurs due to a pressure change of the internal cooker 2, and thus this is the first electrode plate 81 and / or The second electrode plate 82 is moved directly or indirectly, and the effective corresponding area between the first electrode plate 81 and the second electrode plate 82 is changed to generate the changed capacitance signal. Electric pressure cooker. The method of claim 11,
There is a displacement guide rod 14 between the electric heating device 4 and the first electrode plate 81, both ends of the displacement guide rod 14 being the electric heating device 4 and / or the first. Respectively connected to the electrode plate 81, the internal cooker 2 generates a displacement change due to pressure and moves the electric heating device 4, and the electric heating device 4 is the displacement guide rod 14. The first electrode plate 81 is moved by the bottom plate, and the second electrode plate 82 is disposed on the bottom of the outer cooker 1 or on the sidewall of the outer cooker 1 by a bracket 12. An electric pressure cooker, characterized in that the installation. The method of claim 12,
There is a lever device 13 between the displacement guide rod 14 and the first electrode plate 81, the displacement guide rod 14 drives the short arm of the lever device 13 and the long arm is An electric pressure cooker characterized by driving the first electrode plate (81).

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