JPH0423450Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a rice cooker consisting of an outer pot and an inner pot that is detachable from the outer pot. The present invention relates to a temperature sensor for a cooker that detects temperature.

[Conventional technology]

Usually, as shown in FIGS. 3 and 4, a temperature sensor for a cooking appliance is provided with an annular hot plate 12 with a built-in heater at the inner bottom of an outer pot (not shown).
It is constructed in an outer case 6 provided in the central opening of the. That is, the thermistor 4 is disposed within the heat sensitive body 1 which is vertically movably provided within the outer case 6.
The temperature of the inner pot (not shown) is detected and the control circuit is controlled to control the supply of electricity to the hot plate 12.
The heat sensitive element 1 is covered with a lid 3 made of a material with good thermal conductivity, and a thermistor 4 is attached to the fixing metal fitting 1 on the bottom surface of the lid 3.
Fixed by 3. The thermistor 4 is protected by an insulating tube 7 and the like. A board 19 is attached to the lower part of the fixing fitting 13, and the reed switch 8
The leads of the thermistor 4 and the lead wire 20 for extraction are soldered to the board 19. The heat sensitive body 1, which is a movable body, is supported by a coil spring 9 via an inner case 2 with respect to an outer case 6 so as to be movable up and down. Magnets 10 and 11 are fixed inside the outer case 6 by means of a support plate 14 passing through a substrate 19. In this way, the reed switch 8, which is a part of the movable body, moves up and down to approach and move away from the magnets 10 and 11 depending on the presence or absence of the inner pot.

Now, when the inner pot is not placed on the temperature sensor and the heat sensitive element 1 is in the raised position as shown in FIG. 3, the magnetic flux from the magnets 10 and 11 flows into the reed switch 8, and the reed switch 8 is closed. in a state. In this state, regardless of the detection signal from the thermistor 4, the operation of the control circuit is stopped and the current supply to the hot plate 12 is cut off.

Next, when the inner pot is placed on the heat sensitive body 1, the heat sensitive body 1
As the temperature decreases, the reed switch 8 separates from the magnets 10 and 11, the magnetic flux flowing into the reed switch 8 decreases, and the reed switch 8 becomes open. is configured to work.

[Problem that the invention attempts to solve]

Conventionally, the board 19 is used to relay the temperature detection signal line from the thermistor 4 and the inner pot detection signal line from the reed switch 8, and four lead wires 20 (FIG. 4) are used to relay the temperature detection signal line from the thermistor 4 and the inner pot detection signal line from the reed switch 8. The signal is then transmitted to the control circuit. However, when a temperature sensor is used in a rice cooker, rice cooker, etc., heat resistance is required for the connection part, so ordinary solder cannot be used, and high-temperature solder must be used.

In addition, the inner case 2, outer case 6, and the board 19 must be electrically insulated, so either the inner case 2, the outer case 6 are made sufficiently large, or the board 19 is coated with an insulating material. You must take such action. It is also necessary to control the amount of solder.

Further, the lead wire 20 for transmitting the detection signal to the control circuit is directly soldered to the board 19, and the thickness of the board 19 is made thicker in advance to increase the mechanical strength (tensile strength of the lead wire). Or, in order to route the lead wire 20, it is necessary to devise a structure for hooking it to the fixing metal fitting 13.

As described above, it is possible to connect the detection signal line inside the sensor, but on the other hand, the process efficiency decreases due to the use of high-temperature solder to increase heat resistance, and the sensor becomes larger.
It is necessary to control the amount of solder, which increases costs.

[Means for solving problems]

The present invention detects the presence or absence of the object to be heated by a detection element provided on the movable object by moving the movable object by mounting the object to be heated, and also detects the temperature of the object to be heated at the upper part of the movable object. In the temperature sensor for a cooking device that detects the temperature with a temperature sensing element in a heat sensing body provided, the element for detecting the presence or absence of the heated object and the temperature sensing element are placed in a resin holder constituting the movable body. The holder is characterized in that terminals are fixedly installed on both sides of the holder in order to attach the holder and connect them in parallel, and lead wires for detection signals are welded to the terminals.

[Effect]

This invention replaces the conventional fixing metal fittings with resin molded holders to hold thermistors, reed switches, etc.
A terminal for connecting a lead wire is fixedly provided, and the lead of the thermistor 4, the lead of the reed switch, and the lead wire are connected to the terminal by spot welding.

〔Example〕

An embodiment of the temperature sensor for a cooker according to the present invention is shown in FIGS. 1 and 2. As shown in the figure, the movable body is covered with a lid 3 and an inner case 2, and consists of a holder 5 made of resin and having an arcuate portion 51 on both sides of the lower part and a disc-shaped portion 52 on the upper part. The arcuate portion 51 of the holder 5 has a recess 23 for fixing a terminal with an electrically insulated distance, the main plate 53 has a recess 25 for fixing a reed switch, and the disc-shaped portion 52 has a recess 23 for fixing a thermistor. Recesses 26 are provided respectively, and the main plate 53
On both sides there are locking parts 2 for routing the lead wire 20.
4 is provided. The terminal 22 is press-fitted or inserted into the recess 23 of the holder 5 and then fixed with an adhesive or the like. After the core wire portion 29 of the lead wire 20 is spot-welded to the terminal 22, it is hooked to the locking portion 24 of the holder 5 and is inserted into the hole 30 provided in the arcuate portion 51.
It is led out through.

The heat sensitive body 1 has a lid 3 made of a material with good thermal conductivity.
covered with The thermistor 4 protected by a protective tube 7 made of a material with good thermal conductivity is housed in the recess 26 of the holder 5, and the lead 4-a of the thermistor 4 is spot welded to the terminal 22. The reed switch 8 is housed in the recess 25 of the holder 5,
Lead 8-a is spot welded to terminal 22.
The holder 5 has a flange portion 27 of a disc-shaped portion 52 that is connected to the lid 3.
and the flange portion 28 of the inner case 2, and is fixed within the inner case 2 by caulking the side edges of the lid 3, thereby forming a movable body.

Next, the outer case 6 has magnets 10 and 11 as before.
and a support plate 14, and the movable body is supported within the outer case 6 via a coil spring 9 so as to be movable up and down.

Now, when the inner pot as a heated body is not placed on this temperature sensor and the heat sensitive body 1 (movable body) is in the rising position, the magnetic flux from the magnets 10 and 11 flows into the reed switch 8, and the reed switch 8 The closed state is as described above. Also, thermistor 4
The resistance value changes depending on the temperature, and the thermistor 4
Since the temperature detection signal line from the reed switch 8 and the inner pot detection signal line from the reed switch 8 are connected in parallel as described above, when the reed switch 8 is in the closed state as described above, the resistance from the thermistor 4 increases. Regardless of the value (temperature detection signal), the resistance value is always 0 as a detection signal of the temperature sensor. Then,
When there is no inner pot, the operation of the control circuit is stopped to cut off the power supply to the hot plate 12.

Next, when the inner pot is placed on the heat sensitive body 1, the heat sensitive body 1
As the reed switch 8 is lowered, the reed switch 8 separates from the magnets 10 and 11, and the magnetic flux from the magnets 10 and 11 flowing into the reed switch 8 decreases rapidly, and the reed switch 8 becomes in an open state. Here, as the temperature detection signal, since the reed switch 8 is in an open state, a signal representing the resistance value of only the thermistor 4 is sent to the control circuit to control the energization of the hot plate 12.

Since the thermistor 4 is fixed in advance to the heat sensitive element 1 by the holder 5 and is shielded from the outside air, the thermistor 4 can detect the temperature of the lid 3, that is, the temperature of the object to be heated. In addition, the heat resistance required for a temperature sensor is 150℃~
Although the temperature is 180° C., since the detection signal lines are connected by spot welding, the heat resistance is excellent, and the minute detection signals are electrically insulated from the power supply passing through the hot plate 12. Furthermore, since the terminals 22 are fixed in advance, they have excellent strength, and the spot welding of the leads, lead wires 20, etc. can be carried out continuously and easily, and the number of steps can be reduced. In addition, there is no need for other insulation coating materials, and since the holder 5 is integrated, it is possible to downsize the device.

[Effect of idea]

As described above, according to the present invention, heat resistance and reliability are improved by spot welding the detection signal line for the presence or absence of a heated object and the temperature detection signal for the heated object in parallel using the terminal 22. Moreover, since the number of lead wires is reduced from four to two, the number of parts is reduced, the temperature sensor is reliably electrically insulated, and a temperature sensor that can be miniaturized can be provided.

[Brief explanation of drawings]

FIG. 1 is a perspective view of essential parts of a temperature sensor for a cooker according to the present invention, FIG. 2 is an exploded perspective view of a temperature sensor for a cooker according to the present invention, and FIG. 3 is a longitudinal sectional view of a conventional temperature sensor for a cooker. FIG. 4 is a perspective view of the main parts of a conventional temperature sensor for a cooker. 1... Heat sensitive body, 2... Inner case, 3... Lid,
4... Thermistor, 5... Holder, 6... Outer case, 7... Protective tube, 8... Reed switch, 9... Coil spring, 10, 11... Magnet, 1
2...Hot plate, 20...Lead wire, 22...Terminal.

Claims (1)

[Claims for Utility Model Registration] 1. When the movable body is moved by mounting the heated body, a detection element provided on the movable body detects the presence or absence of the heated body, and the temperature of the heated body is detected. In a temperature sensor for a cooking appliance, which detects temperature by a temperature sensing element in a heat sensitive body provided on the upper part of the movable body, the element for detecting the presence or absence of the heated body and the temperature sensing element are connected to a resin constituting the movable body. 1. A temperature sensor for a cooker, characterized in that the temperature sensor is mounted on a holder made of aluminum, and has terminals fixed on both sides of the holder to connect them in parallel, and a lead wire for a detection signal is welded to the terminal. 2. The element for detecting the presence or absence of the object to be heated is constituted by a reed switch and a magnet, and the temperature sensing element is formed by covering the temperature sensing element with an insulating protection tube with good heat conduction. A temperature sensor for a cooker according to claim 1, characterized in that it is a utility model.