JP3622252B2 - Table stove - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a table stove equipped with a safety device that performs fuel supply control at the time of extinction, and firepower control such as fire extinguishing when a pan bottom temperature is detected and reaches a set temperature.
[0002]
[Prior art]
The table stove uses a thermocouple for detection of extinction and a PTC thermistor for detection of pan bottom temperature for the purpose of preventing tempura fire, and these are separately or combined to form a circuit and provided in the gas supply path. A safety device that closes the solenoid valve when it goes out or overheats at the bottom of the pan is used in association with the solenoid valve. However, depending on the configuration of the safety device, the performance of the table stove is affected by the room temperature resistance value of the PTC thermistor, and problems such as cost increase due to the use of the control board may occur. We have already provided an invention for an electromagnetic valve that has two electromagnets attached to one main body so that each can be excited independently, and the valve body can be held by suction only when both electromagnets are excited. By connecting the thermocouple to one electromagnet of the solenoid valve and the energization control circuit using the PTC thermistor and power supply to the other electromagnet, even one solenoid valve can be used without affecting the performance of the table stove. In addition, a safety device that can be configured at low cost can be realized.
[0003]
[Problems to be solved by the invention]
However, even in a table stove using the above-described improved solenoid valve, the detection of the pan bottom temperature is intended to prevent a fire in low-temperature heating cooking such as the tempura cooking, so for this reason the set temperature for operating the safety device The upper limit is limited to about 250 ° C., and high-temperature heating cooking (about 350 ° C.) such as stir-fried foods and grilled foods cannot be performed, and the usability of the table stove itself becomes poor.
[0004]
[Means for Solving the Problems]
Therefore, the present invention provides a table stove that can be cooked at a higher temperature by newly adding a function of temporarily releasing the operation of the PTC thermistor to the safety device using the improved electromagnetic valve. The configuration is characterized in that the energization control circuit is provided with a short circuit capable of short-circuiting the PTC thermistor and switch means for opening and closing the short circuit.
It is desirable that the opening operation of the short circuit by the switch means is performed in conjunction with a fire extinguishing operation or an ignition operation.
Further, it is desirable to provide display means for informing the open / close state of the short circuit.
[0005]
[Action]
When performing low-temperature cooking, if the short circuit is opened by the switch means, the PTC thermistor is activated, and the energization amount of the energization control circuit decreases due to the sudden increase in the electrical resistance value due to the set temperature reaching the PTC thermistor. The excitation of the other electromagnet is released, the electromagnetic valve is closed, and the gas supply path is closed. However, if the short circuit is closed by the switch means, even if the PTC thermistor reaches the set temperature and the energization amount decreases there, the energization on the short circuit side is maintained, so the set temperature of the PTC thermistor is exceeded. High temperature cooking is possible.
Further, if the opening operation of the short circuit by the switch means is linked to the fire extinguishing or ignition operation, the short circuit is always opened at the time of extinguishing at the end of high temperature heating cooking or ignition at the next cooking, and the set temperature of the PTC thermistor The safety function that is activated in is restored.
Furthermore, if a display means for informing the open / closed state of the short circuit is provided, the open / closed state can be visually confirmed, and misuse can be avoided.
[0006]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
Example 1
FIG. 1 is a circuit diagram of a safety device in a table stove. As will be described in detail later, the magnet electromagnetic valve 1 here has two coils 23 and 29, and is only opened when a current flows through both coils. 1 body 2 electromagnet type having a valve body to be held by a valve, and one coil 23 is connected in series with a thermocouple 2 arranged in the vicinity of the burner head to constitute a thermocouple circuit 3 and the other coil 23 The coil 29 (small current type) is disposed on the bottom of the pan and is connected to an energization control circuit 4 including a PTC thermistor 6 whose electrical resistance value increases rapidly when a set temperature (250 ° C. in this case) is reached. The energization control circuit 4 is connected to a dry battery 5 as a power source in series with the PTC thermistor 6, resistor 7, coil 29, and switch 8 linked to the ON operation of the ignition switch. A release switch 9 that is turned on, an electromagnetic relay 10 that opens and closes a normally open contact 11 in parallel with the PTC thermistor 6, and a reset switch 12 that is turned off by a push operation are also arranged in series and connected to the dry battery 5. Reference numeral 13 is a resistor connected to the output side of the normally open contact 11, and 14 is an LED lamp for displaying a release warning, which is also connected to the output side of the normally open contact 11 and is turned on when the normally open contact 11 is closed. .
Next, the structure of the magnet solenoid valve 1 used here will be described. In FIG. 2, a base 21 having a flange 22 is fitted to one end of a cylindrical casing 20, and the coil 23 of the thermocouple circuit 3 is wound on the casing 20 side of the base 21. The base end portion of the rotated U-shaped fixed iron core 24 is fitted and fixed to constitute the first electromagnet 25. On the other hand, the other end of the casing 20 is a closed portion 26, and through-holes 28, 28 through which a U-shaped movable iron core 27 penetrates are formed in the closed portion 26. The second electromagnet 30 is configured by enclosing a small current type coil 29 in the energization control circuit 4 with a larger number of turns than the coil 23 around 28. A ring-shaped movable piece 31 is disposed between the fixed iron core 24 and the movable iron core 27 in a free state. The movable piece 31 is inserted into the central through hole 31a from the closing portion 26 to the casing 20. The guide part 26a extended to the fixed iron core 24 side so as to coincide with the axial center of the shaft penetrates, so that the sliding in the axial direction is guided. Further, the movable iron core 27 is connected to the base end portion of the valve shaft 33 in a housing 32 connected to the casing 20, and the distal end portion of the valve shaft 33 passes through the housing 32 and is outside the valve body 34. , And is urged toward the tip by a compression spring 35 provided between the valve body 34 and the housing 32. Reference numerals 36a and 36b denote terminal fittings connected to the coils 23 and 29, respectively.
[0007]
In the safety device configured as described above, when the valve element 34 of the magnet electromagnetic valve 1 is forcibly pushed by the ON operation of the ignition switch, the movable core 27 and the movable piece 31 are moved backward toward the fixed core 24 side. Touch. At this time, the switch 8 of the energization control circuit 4 is closed, a current flows to the coil 29, the second electromagnet 30 is excited, and a current flows to the coil 23 due to the rise of the thermoelectromotive force of the thermocouple 2 after ignition. Since the first electromagnet 25 is also excited, the valve open state is maintained as shown in FIG.
Here, when the burner disappears, the excitation of the first electromagnet 25 is released due to the decrease in the thermoelectromotive force applied to the coil 23, so that the movable iron core 27 is urged by the compression spring 35 while adsorbing the movable piece 31. It moves to the position of FIG. 2 (B) with 33 and the valve body 34, and cuts off supply of gas. On the other hand, when the pan bottom temperature rises and the PTC thermistor 6 reaches the set temperature, the electric resistance value increases rapidly, the amount of current supplied to the coil 29 decreases, and the excitation of the second electromagnet 30 is released. The piece 31 is left on the fixed iron core 24 side, and the valve shaft 33 and the valve body 34 together with the valve shaft 33 and the valve body 34 are returned to the valve closing position by the urging force of the compression spring 35 as shown in FIG. .
However, if the release switch 9 in the energization control circuit 4 is pushed and turned on before the PTC thermistor 6 reaches the set temperature, the electromagnetic relay 10 is energized and the normally open contact 11 is closed by the excitation. Self-holding. Then, since the power is supplied from the normally open contact 11 to the coil 29 via the resistor 13, even if the PTC thermistor 6 reaches the set temperature and the energization amount decreases there, the magnet electromagnetic valve 1 is kept open. It is maintained, and high-temperature cooking at a set temperature or higher becomes possible. At this time, since the LED lamp 14 is lit, the release of the safety device can be visually confirmed.
When the reset switch 12 is pushed and turned off from the released state, the energization to the electromagnetic relay 10 is stopped, the self-holding of the normally open contact 11 is released, and the energization to the coil 29 is stopped. The operating state is restored by the thermistor 6. At the same time, since the LED lamp 14 is also turned off, the set state of the safety device can be confirmed. Therefore, if the reset switch 12 is linked to a fire extinguishing lever or an ignition switch, it automatically operates at the set temperature of the PTC thermistor 6 (upper limit of low temperature heating cooking) by the fire extinguishing operation at the end of the high temperature heating cooking or the subsequent ignition operation. The safety function will be restored.
[0008]
Example 2
In the first embodiment, the high-temperature heating cooking and the resetting can be performed in the circuit configuration, and an embodiment in which the above functions are given with a simple machine structure will be described below.
In the circuit diagram of FIG. 3, the energization control circuit 4 a is formed by connecting the resistor 7, the PTC thermistor 6, the coil 29, and the switch 8 in series to the dry battery 5, and connecting the release switch 15 to the PTC thermistor 6 and the resistor 7. A resistor 16 is connected in parallel. In particular, the release switch 15 is opened and closed by sliding the release lever 15a to an upper limit position (switch closed) and a lower limit position (switch open) as shown in FIGS. 4 is a slide switch that operates in conjunction with the ignition button 40 and rotates in the left-right direction in FIG. 4 with an operating lever 41 whose distal end rotates in the left-right direction in FIG. 4 with the pivot 42 at the base end as a fulcrum. The return lever 43 that moves is linked to each other, and the release lever 15a is pushed down to the lower limit position. As shown in detail in FIG. 5, the contact piece 41a extended at the upper end of the operating lever 41 that rotates by pushing the ignition button 40 pushes the hanging piece 43a of the return lever 43, and the return lever 43 rotates. When moved, the arm portion 45 of the return lever 43 moves downward to push down the release lever 15a. The release lever 15a protrudes from the table cooker body. When the release button 15 is released after the ignition button 40 has been pressed, the operating lever 41 returns to the heart cam lock position by the return force of the heart cam (not shown). 41 and the return lever 43 are retracted and the release lever 15a is in a free state, so that the vertical movement operation can be manually performed along with the confirmation of the position.
Therefore, in this embodiment, when the ignition button 40 is pushed, the operation lever 41 is rotated, and the spindle of the flashing device 46 in which the magnet electromagnetic valve 1 is incorporated is pushed in, so that the magnet electromagnetic as shown in FIG. The valve 1 is forcibly opened, and at the same time, as described above, the release lever 15a of the release switch 15 is automatically pushed downward by the linkage of the return lever 43 from the operating lever 41, and the release switch 15 is opened. Since the switch 8 is closed by the operation of the ignition button 40, the power is supplied from the resistor 7 to the coil 29 through the PTC thermistor 6. Thereafter, the coil 23 is energized by the increase in the thermoelectromotive force of the thermocouple 2, so that the magnet electromagnetic valve 1 is held as it is by suction.
[0009]
When the pan bottom temperature rises and reaches the set temperature, the amount of current supplied to the coil 29 decreases due to the sudden increase in the electrical resistance value of the PTC thermistor 6, and the magnet solenoid valve 1 is closed as shown in FIG. However, if the release lever 15a is moved upward by manual operation before the valve is closed, the release switch 15 is closed and current flows from the resistor 16 and the release switch 15 side to the coil 29. Therefore, the PTC thermistor Even when 6 reaches the set temperature and the energization amount decreases there, energization in the energization control circuit 4a is maintained, and high-temperature cooking that exceeds the set temperature of the PTC thermistor 6 becomes possible.
This high-temperature heatable state resetting is performed as described above, because the release lever 15a is automatically pushed down and the release switch 15 is opened by the push operation of the ignition button 40 accompanying the fire extinguishing, so that the safety device is released. The next cooking is not performed with the setting, and the safety function is surely restored.
[0010]
In the first and second embodiments, the safety device does not operate when the PTC thermistor is short-circuited. However, in this energization control circuit, a high-temperature setting PTC thermistor (for example, one having a set temperature of 350 ° C.) is placed on the short-circuit side. If connected, the magnet solenoid valve is closed at the set temperature even in high-temperature cooking, and can be used more safely.
[0011]
【The invention's effect】
As described above, according to the present invention, in the table stove employing the safety device using the improved solenoid valve, in addition to the original effect that the safety device can be easily configured at low cost, it becomes possible to cook at a higher temperature, and the table stove The ease of use will be further improved.
Also, if the opening operation of the short circuit by the switch means is linked to the fire extinguishing or ignition operation, the short circuit is always opened at the time of extinguishing at the end of high temperature cooking or ignition at the next cooking, so there is no need to forget to return it. Safety is increased.
Furthermore, if a display means for notifying the open / closed state of the short circuit is provided, the open / closed state can be confirmed visually and misuse can be avoided.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of a table stove safety device in Embodiment 1. FIG. 2 (A) is an explanatory diagram of a magnet solenoid valve.
(B) It is explanatory drawing of a magnet solenoid valve.
(C) It is explanatory drawing of a magnet solenoid valve.
FIG. 3 is a circuit diagram of a safety device for a table stove according to a second embodiment.
4 is a schematic configuration diagram of a table stove in Embodiment 2. FIG.
FIG. 5 is an explanatory diagram showing a linkage structure between a release switch and an ignition button in Embodiment 2.
[Explanation of symbols]
1 .... Magnet solenoid valve, 2 .... Thermocouple, 3 .... Thermocouple circuit, 4,4a ... Electrification control circuit, 5 .... Dry battery, 6 .... PTC thermistor, 7,13,16 ... Resistance, 8 ..Switch, 9, 15 ... Release switch, 10 .... Electromagnetic relay, 11 .... Normally open contact, 12 .... Reset switch, 23, 29 ..., Coil, 40 ... Ignition button, 41 ... Operating lever, 43 ... Return lever.

Claims (3)

One valve body that is energized in the valve closing direction and is forcibly opened by manual operation or electric driving force, and two electromagnets that are provided in one body and can be individually excited, Only when both electromagnets are excited, the solenoid valve has an electromagnetic valve that adsorbs and holds the valve element to open the gas supply path, and one electromagnet of the electromagnetic valve is connected to a thermocouple disposed in the vicinity of the burner. A table stove connected to the energization control circuit in which the other electromagnet is connected in series with a PTC thermistor and a power source whose electrical resistance value increases rapidly at the set temperature due to the temperature rise at the bottom of the pan,
A table stove characterized in that a short circuit for short-circuiting the PTC thermistor and switch means for opening and closing the short circuit are provided in the energization control circuit. The table stove according to claim 1, wherein the opening operation of the short circuit by the switch means is linked to a fire extinguishing operation or an ignition operation. The table stove according to claim 1 or 2, further comprising display means for notifying an open / closed state of the short circuit.

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