JPH11126552A - Thermal fuse equipped with temperature measuring element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make unnecessary a thermal fuse and a thermistor assembled separately into parts for assembling at the time of manufacturing a product and provide a thermal fuse equipped with a temperature measuring element whose thermal fuse can be fixed directly in a heating part. SOLUTION: A movable cylinder 7 comprising a metal container 4 whose bottom face works as a heat receiving face and an insulating cap 6 which is fitted slidably in the metal container 4 and works as a contacting part for a movable contact 5 to bring the movable contact 5 into contact with the base ends of the fixed electrodes 2, 3 at the tip part to communicate both fixed electrodes 2, 3 are housed in an insulation case 1 containing a pair of the fixed electrodes 2, 3, a spring 8 is installed for parting the movable contact 5 from the fixed electrodes 2, 3, an elastic member 9 to apply resilient force to the movable contact 5 in order to push the movable contact 5 to both fixed electrodes 2, 3 and a fusible metal body 10 to de-energize the resilient force of the elastic member 9 by being melted in overheating are housed in the movable cylinder 7, a temperature measuring element 12 is attached to a recess formed in the bottom face of either the metal container 4 or the metal cover 11, and lead wires 13, 14 of the element 12 are supported in the insulating case 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a rice cooker, a jar,
The present invention relates to a temperature fuse for controlling the temperature of a heating appliance such as a pot and preventing overheating.

[0002]

2. Description of the Related Art In recent years, heating electric appliances such as rice cookers, jars, pots, and the like have been provided with microcomputers for temperature control and the like, and multifunctions have been achieved. In order to perform fine temperature control, an analog-type temperature measuring element such as a thermistor is installed in the heating section to obtain a temperature signal necessary for microcomputer control. Further, a thermal fuse is also used for protecting appliances and electronic circuits when abnormal temperature rises.

[0003] These thermistors and thermal fuses are separate parts having different functions, and have been mounted at different locations of the heat generating part. For example, in the case of a pot, as shown in FIG. 10, a thermistor element is housed in a metal cap 21 and sealed with a glass seal 22, and a lead wire 23 is connected to a lead wire 25 by a crimp terminal 24, and Is insulated by a silicon tube 26, and a component having a connector 27 attached to an end of a lead wire is used. As shown in FIG. It is fixed so as to be pressed. The thermal fuse 31 has a fuse element sealed in a cylindrical housing, and is fixed at a position away from the center of the mounting plate 29 of the pot.

As described above, in the related art, in order to increase the accuracy of temperature control, a thermistor is provided at a central portion of heat generation, and a thermal fuse is often mounted near the center. Then, an operation error and a delay of the thermal fuse appear, which is not preferable. The thermal fuse is 1
Since the commercial power supply of 00V, 220V, etc. is directly cut off and the voltage is applied directly to the element of the thermal fuse, it must be insulated in order to prevent electric shock and electric leakage when mounting it on equipment. No. Since the insulator is usually made of a material having low heat conductivity, the heat transfer coefficient is also lowered here. Furthermore, a large mounting space is required.

In order to solve such a problem and manage the temperature fuse and the thermistor at substantially the same temperature, there is a case in which the temperature fuse and the thermistor are provided in one case. As shown in FIG. 12, for example, as shown in FIG. 12, a lead wire 43 is connected to a terminal of a thermal fuse 41 in which a fuse element is sealed in a cylindrical housing by a crimp terminal 42, The exposed metal portion of the terminal 42 is covered with an insulating tube 44. A connector 45 is attached to an end of the lead wire 43. The thermistor is connected to the terminal 4 of the glass-enclosed thermistor element 46 as shown in FIG.
7, a lead wire 50 is connected to the thermistor element 46 and the crimp terminal 48 with a metal exposed portion covered with an insulating tube 49. A connector 51 is attached to an end of the lead wire 50.

The temperature fuse 41 and the thermistor element 46 are respectively mounted in recesses formed in the aluminum holding metal fitting 52 as shown in FIG. 11, covered with an aluminum temperature sensing plate 53, and integrated with a cylindrical portion 55 by a caulking portion 54. As shown in FIG. 14, the bottom plate 58 of the rice cooker is mounted so that the front end engaging portion 56 of the leg is engaged with the cutout portion of the central hole 59 of the bottom plate 58 of the rice cooker.
A spring 6 is provided between the cylinder 57 and the ring 57 attached to the cylinder 55.
0 is attached so that the bottom of the inner container (not shown) of the rice cooker elastically contacts the aluminum temperature sensing plate 53.

[0007]

However, FIG.
The conventional thermal fuse and thermistor assembly described in FIGS. 14 to 14 are generally used to assemble thermistors and thermal fuses of different parts from different manufacturers at the time of product manufacture. There was a problem that it took time and cost for parts and assembly. Further, since the thermal fuse is usually an insulator having a low thermal conductivity, the conventional example requires insulation by the insulating tube 44, the thermal fuse cannot be directly fixed to the heat generating portion, and the thermal conductivity is deteriorated if there is an insulating coating. There was a problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide a temperature measuring device which does not require assembling a thermal fuse and a thermistor into separate assembly parts when manufacturing a product, and which can directly fix the thermal fuse to a heat generating portion. An object of the present invention is to provide a thermal fuse with an element.

[0009]

In order to solve the above-mentioned problems, a temperature fuse with a temperature measuring element according to the present invention is provided in a metal container having a bottom surface serving as a heat receiving surface in an insulating case having an opening at one end where a pair of fixed electrodes is fixed. And slidably fit into this metal container,
A movable tubular body comprising an insulating cap that is a contact portion with a movable contact that abuts on a base end of the pair of fixed electrodes and makes contact between the fixed electrodes is housed, and the movable contact is placed in the insulating case. A spring for separating the fixed contacts from the fixed electrodes is provided, a resilient member for providing a resilient force for pressing the movable contact against the fixed electrodes against the urging force of the spring, and a resilient member for melting when overheated. A fusible metal body for deenergizing the elastic force of the firing member is housed in the movable cylinder, and is directly in contact with the bottom surface of the metal container or integrated with the bottom surface of the metal container, to be an electrical device to be overheat protected. A metal cover that is attached in close contact is attached to the opening of the insulating case, a temperature measuring element is attached to the bottom of the metal container or a recess formed on the bottom of the metal cover, and the lead wire of the temperature measuring element is disconnected. It is obtained by supporting the case.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments shown in the drawings. 1 to 4 show a first embodiment of the present invention. FIG.
3 is a sectional view taken along line AA of FIG. 1, FIG. 3 is a sectional view taken along line BB of FIG. 1, and FIG. 4 is a bottom view.

In this embodiment, a pair of fixed electrodes 2
A metal container 4 having a bottom surface serving as a heat-receiving surface and slidably fitted to the metal container 4 in an insulating case 1 having an opening at one end to which the fixed electrode 3 is fixed. A movable cylindrical body 7 comprising an insulating cap 6 which is a contact portion with a movable contact 5 which comes into contact with the fixed electrodes 2 and 3 is housed, and the movable contact 5 is placed in an insulating case 1 by the fixed electrode 2. A spring 8 for separating the movable contact 4 from the fixed electrodes 2 and 3 against the urging force of the spring 8; A fusible metal body 10 that is sometimes melted to deactivate the resilience of the resilient member is housed in the movable cylinder 7 and directly contacts the bottom surface of the metal container 4 or the bottom surface of the metal container 4 Attached in close contact with overheat protected electrical equipment Attaching the cover 11 to the opening of the insulating case 1, the bottom or recess formed on the bottom surface of the metal cover 11 of the metal container 4, the thermistor element 12
And the lead wires 13 and 14 of the thermistor element 12
Are supported in the insulating case 1. In the figure, 15 and 16 are lead wires of the fixed electrodes 2 and 3, 17 is a disk provided between the fusible metal body 10 and the resilient member 9, and 18 is a temperature-sensitive cover.

The temperature fuse with the temperature measuring element having the above configuration is
As shown in FIG. 5, a spring 72 attached to the attachment plate 71 of the jar pot 70 attaches the pot inner cylinder 73 so as to be pressed against the center of the bottom. The connector 74 of the thermal fuse and the connector 75 of the temperature measuring element are connected to a power supply circuit and a temperature control circuit, respectively.

In the case of a rice cooker, an inner pot 83 is attached to a mounting plate 81 of a rice cooker 80 via a spring 82 as shown in FIG.
So that it is pressed against the center of the bottom of.

In the first embodiment, during normal temperature control, the temperature of the pot or the bottom central portion of the rice cooker is measured by the thermistor element 12, and the temperature is controlled by the microcomputer. When the temperature at the center of the bottom of the pot or the rice cooker rises abnormally, the soluble metal body 10 in the movable cylinder 7 melts at the set temperature, so that the compressed resilient member 9 is liquefied. The movable contact 5 is extended from the fixed electrodes 2 and 3, and the movable contact 5 is disengaged from the fixed electrodes 2 and 3 with the biasing force of the resilient member 9 reduced. As a result, the commercial power supply connected to the leads 15 and 16 is directly shut off.

FIG. 7 shows a second embodiment of the present invention. In the first embodiment, the thermistor element 12 is connected to the metal cover 1.
1 is mounted in a recess formed on the bottom surface, and the temperature-sensitive cover 18 is mounted on the outside thereof.
8, the metal cover 11 'is directly attached to the bottom of the insulating case 1 so that the thermistor element 12 is exposed.

FIG. 8 shows a third embodiment of the present invention. In this embodiment, a concave portion is formed on the bottom surface of the metal container 4 and the thermistor element 12 is mounted in the concave portion.

[0017]

As described above, according to the present invention, the following effects can be obtained. (1) In order to attach two components to the heat generating portion, a housing for attachment is required, but this is not required. (2) The measured temperatures of the thermal fuse and the thermistor are the same, and there is no time delay. (3) Insulation must be devised to prevent contact between the two lead wires, but this is not required. (4) The set maker only needs to consider the mounting of one part of the product, which simplifies the design and eliminates the need for assembly and processing and procurement of the parts required for the assembly. It becomes compact by integrating.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a bottom view of the first embodiment.

FIG. 5 is a sectional view showing an example in which the first embodiment is attached to a jar.

FIG. 6 is a sectional view showing an example in which the first embodiment is attached to a rice cooker.

FIG. 7 is a sectional view of a second embodiment.

FIG. 8 is a sectional view of a third embodiment.

FIG. 9 is a cross-sectional view showing a state where a conventional thermal fuse and a thermistor are mounted.

FIG. 10 is a perspective view of a conventional thermistor component.

FIG. 11 is a cross-sectional view of a conventional assembly combining a thermal fuse and a thermistor.

FIG. 12 is a front view showing a configuration of a conventional thermal fuse.

FIG. 13 is a front view showing a configuration of a conventional thermistor component.

14 (a) is a partially cutaway front view showing a state of attachment of a conventional assembly, and FIG. 14 (b) is a bottom view of a center hole for attaching the assembly.

[Explanation of symbols]

1 Insulation case, 2, 3 fixed electrodes, 4 metal container, 5
Movable contact, 6 insulating cap, 7 movable cylinder, 8 spring, 9 resilient member, 10 fusible metal body, 11 metal cover, 12 thermistor element, 13, 14, 15,
16 lead wires, 17 discs, 18 thermal cover,
70 jar pot, 71 mounting plate, 72 spring,
73 pot inner cylinder, 74 connector, 75 connector,
80 rice cooker, 81 mounting plate, 82 spring, 83
Inner pot

Claims (1)

[Claims] 1. A metal container having a bottom surface serving as a heat receiving surface, slidably fitted in the metal container, and a top portion of the pair of fixed electrodes fixed in an insulating case at one end opening to which the pair of fixed electrodes is fixed. For accommodating a movable cylindrical body composed of an insulating cap which is a contact portion with respect to a movable contact which abuts on a base end and makes contact between the fixed electrodes, and for separating the movable contact from the fixed electrodes in the insulating case. A spring is provided, and a resilient member for providing a resilient force for pressing the movable contact against the two fixed electrodes against the urging force of the spring and a resilient member which melts when overheated to extinguish the resilient force of the resilient member. The movable metal body to be energized is housed in the movable cylindrical body, and a metal cover which is in direct contact with the bottom surface of the metal container or integrated with the bottom surface of the metal container, which is attached in close contact with an electric device to be overheat protected. Opening of the insulating case A temperature measuring element attached to a bottom portion of the metal container or a concave portion formed on a bottom surface of the metal cover, and a lead wire of the temperature measuring element is supported by the insulating case. Thermal fuse.