JP2993271B2 - Electric water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric water heater for heating and keeping a liquid contained therein.

[0002]

2. Description of the Related Art A conventional electric water heater of this type has a structure as shown in FIGS. 10 to 11, for example. That is, in the drawing, reference numeral 101 denotes a bottomed cylindrical container provided in an exterior body 102, a heating element 103 is fixed to the back side of the bottom surface of the container 101, and a temperature detecting device 104 is mounted on the back side of the central bottom of the container 101. I am wearing it. Reference numeral 105 denotes a control board that controls the energization of the heating element 103 by an electric signal from the temperature detecting device 104. The temperature detecting device 104
Is a heat-sensitive plate 106 made of a cylindrical metal having a flat portion on the upper surface and a through hole on the side surface, a temperature sensor 108 mounted on the through-hole via an insulating material 107, and a cover 109 for supporting the heat-sensitive plate 106. And the heat-sensitive plate 106 placed on the cover 109 is attached and fixed by a mounting spring 110 which presses and urges the bottom surface of the container 101 via the cover 109.

[0003]

In such a conventional electric water heater, when the thermal mass of the heat sensitive plate 106 is large and the temperature of the container 101 changes abruptly, for example, when a small amount of water is being boiled or the water is cooked in an empty state, the temperature of the temperature sensor 108 is reduced. There is a problem that the detection is delayed, the boiling time or the empty cooking detection time becomes longer, the temperature of each part rises, the discoloration of the container 101 occurs, and the corrosion resistance deteriorates.

[0004] In addition, even when it is desired to add water during the heat retention and to make the kettle hot, if the temperature detection of the temperature sensor 108 is delayed, there is a problem that the hot water does not boil.

[0005] The present invention solves the above-mentioned problems, and by adopting a temperature detection structure that can respond to a rapid temperature change in the container, it is possible to improve the detection performance of boiling and empty cooking, the corrosion resistance of the container, and the like. It is an object of the present invention to provide an easy-to-use electric water heater such that re-watering can be performed immediately.

[0006]

According to the present invention, in order to achieve the above object, a first means comprises a bottomed cylindrical container provided in an exterior body, a heating element fixed to the back side of the bottom surface of the container, It consists of a temperature detecting device mounted on the back side of the bottom of the container and a control board that controls the energization of the heating element by an electric signal from the temperature detecting device, and the temperature detecting device has a flat portion at an upper portion and a lower portion at a lower portion. A heat-sensitive plate made of a plate having a U-shaped concave portion, a temperature sensor mounted on the concave portion via an insulating material, and a cover covering the concave portion with a gap from the concave portion, and placed on the cover The plate is mounted and fixed with a mounting spring that presses and presses the bottom surface of the container via the cover, and the protrusion provided on the cover presses the insulating material and the lead of the temperature sensor covered with the insulating material toward the heat-sensitive plate. It is a force.

A second means is that the insulating material and a lead portion of the temperature sensor covered with the insulating material are brought into close contact with a lower surface of the heat-sensitive plate by a projection provided on the cover.

A third means is to fill or insert a material having good thermal conductivity between the insulating material and the temperature sensor covered with the insulating material or the lead portion of the temperature sensor or both.

A fourth means is to fill or insert a material having good thermal conductivity between the insulating material and the heat sensitive plate.

The fifth means is a method in which both ends of the concave portion of the heat-sensitive plate into which the temperature sensor and the insulating material are inserted are caulked.

A sixth means is that a cover is provided with a hole for passing a lead portion of a temperature sensor covered with an insulating material, and a heat insulating portion is provided to cover the entire outer periphery of the heat sensitive plate.

A seventh means is that the temperature sensor is bonded and fixed between the insulating material having good thermal conductivity and the cover.

[0013]

According to the first aspect of the present invention, there is provided:
Formed with a plate material to reduce the thermal mass of the heat-sensitive plate, a temperature sensor is attached via an insulating material between the U-shaped concave portion provided at the bottom of the heat-sensitive plate and the upper flat portion, and pressed against the bottom of the container. Since the protrusion provided on the cover presses and urges the insulating material and the lead of the temperature sensor covered with the insulating material toward the heat-sensitive plate to improve the adhesion between the temperature sensor and the heat-sensitive plate, the container It is possible to improve the followability of the temperature sensor to a change in temperature of the container, and to approximate the temperature of the container to the temperature detected by the temperature sensor. Thereby, the temperature can be detected by quickly following a rapid temperature change in the container, so that it is possible to improve the detection performance of boiling and empty cooking, to improve the corrosion resistance of the container, and to quickly cope with reheating.

According to a second aspect of the present invention, the insulating member and the lead portion of the temperature sensor covered with the insulating member are brought into close contact with the lower portion of the flat surface of the heat-sensitive plate by the projection provided on the cover. The ability of the temperature sensor to follow changes in temperature can be further improved, and the temperature of the container and the temperature detected by the temperature sensor can be made closer to each other. You can get it.

In the means for solving the third problem, a material having good thermal conductivity is filled or inserted between the insulating material and the temperature sensor covered with the insulating material, the temperature sensor lead portion, or both. In addition, heat dissipation from the temperature sensor can be reduced, and the temperature of the heat-sensitive plate and the temperature detected by the temperature sensor can be more approximated. In addition, it is possible to reduce the influence on the performance due to the dimensional variation of each part and the like, thereby improving the reliability and obtaining stable quality.

In the fourth means for solving the problems, since the material having good heat conductivity is filled or inserted between the insulating material and the heat sensitive plate, the temperature of the heat sensitive plate can be more reliably transferred to the temperature sensor. The temperature of the container can be detected more accurately. In addition, when the temperature sensor covered with insulating material is installed between the U-shaped concave part provided at the bottom of the heat sensitive plate and the flat part at the top, the influence on performance due to assembly variation is reduced, and stable performance and quality are reduced. Can be obtained.

According to the fifth aspect of the present invention, since both ends of the concave portion of the heat-sensitive plate into which the temperature sensor and the insulating material are inserted are caulked, the adhesion between the temperature sensor and the insulating material and the heat-sensitive plate can be improved. In addition, the temperature of the heat sensitive plate can be more reliably conducted to the temperature sensor, and the temperature of the container can be detected more accurately. In addition, processing variations can be suppressed, and the workability and assemblability can be improved by treating the temperature sensor and the heat sensitive plate covered with the insulating material as one unit.

According to a sixth aspect of the present invention, a cover is provided with a hole for passing a lead portion of a temperature sensor covered with an insulating material, and a heat insulating portion for covering the entire outer peripheral portion of the heat sensitive plate. The temperature of the container can be detected more accurately because it is hardly affected by fluctuations in the ambient temperature and the ambient temperature. Further, the leadability of the temperature sensor is passed through a hole provided in the cover to be integrated, thereby improving the assemblability.

In the means for solving the seventh problem, since the temperature sensor is adhered and fixed between the insulating material having good thermal conductivity and the cover and is brought into close contact with the back side of the bottom surface of the container, the temperature of the container can be detected more accurately. You can do it. Further, the number of parts can be reduced, cost power can be enhanced, and assembling workability can be improved.

[0020]

【Example】

(Embodiment 1) First, a first embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

As shown in the figure, the container 1 is a cylindrical container having a bottom and is provided inside an exterior body 2. On the back side of the bottom surface of the container 1, a heating element 3 is pressed and fixed by a back plate 4.

On the back side of the bottom of the container 1, a temperature detecting device 5 is mounted. The temperature detecting device 5 has a flat portion 6
A heat sensitive plate 8 in which a U-shaped recess 7 is integrally formed of a plate material at a lower portion, a temperature sensor 10 such as a thermistor mounted in the U-shaped recess 7 with an insulating material 9 interposed therebetween, and a U-shaped recess. It comprises a concave portion 7 and a cover 11 that covers the periphery with a gap.

A protrusion 12 is provided on the upper surface of the cover 11, and the heat-sensitive plate 8 is supported by the protrusion 12 to provide a gap between the heat-sensitive plate 8 and the cover 11.

The temperature detecting device 5 constituted by placing the heat-sensitive plate 8 on the cover 11 is mounted and fixed by a mounting spring 13 which presses and biases the bottom surface of the container 1 via the cover 11.
The protrusions 14 provided on the substrate 1 urge the insulating material 9 and the leads 15 of the temperature sensor 10 covered with the insulating material 9 toward the heat-sensitive plate 8.

Reference numeral 16 denotes a control board, which controls energization of the heating element 3 by an electric signal from the temperature detecting device 5.

In the above-described configuration, when the liquid is stored in the container 1 and the energization is started, the heating element 3 is heated to heat the liquid in the container 1 and a predetermined temperature is detected by the temperature detecting device 5 attached to the lower part of the container 1. It is controlled to the liquid temperature.

Here, in the first embodiment, in order to reduce the thermal mass of the heat-sensitive plate 8, the heat-sensitive plate 8 is formed of a plate material.
A temperature sensor 10 is mounted between a U-shaped concave portion 7 provided at the lower part of the container and an upper flat part 6 via an insulating material 9, pressed against the bottom of the container 1, and pressed by a projection 14 provided on a cover 11. Insulating material 9 and temperature sensor 10 covered with insulating material 9
Of the temperature sensor 10 and the heat-sensitive plate 8 to improve the adherence between the temperature sensor 10 and the heat-sensitive plate 8, so that the followability of the temperature sensor 10 to a temperature change of the container 1 can be improved. The temperature 1 and the temperature detected by the temperature sensor 10 can be approximated. Thus, the temperature can be detected immediately following a rapid temperature change in the container 1, so that the performance of detecting the boiling and empty cooking, the corrosion resistance of the container, and the response at the time of re-boiling can be quickly performed.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to FIGS.

As shown in the figure, the insulating material 9 and the lead 15 of the temperature sensor 10 covered with the insulating material 9 are brought into close contact with the lower surface 17 of the heat-sensitive plate 8 by the protrusions 14 provided on the cover 11. Therefore, the ability of the temperature sensor 10 to follow the temperature change of the container 1 can be further improved, and the temperature of the container 1 and the temperature detected by the temperature sensor 10 can be more approximated. The influence is reduced, and stable high performance can be obtained.

(Embodiment 3) Next, a third embodiment of the present invention will be described with reference to FIGS.

As shown in the figure, a material 18 having good thermal conductivity is filled or inserted between the insulating material 9 and the temperature sensor 10 or the temperature sensor lead 15 or both of which are covered with the insulating material 9. Therefore, heat dissipation from the temperature sensor can be reduced, and the temperature of the heat-sensitive plate 8 and the temperature detected by the temperature sensor 10 can be more approximated. In addition, it is possible to reduce the influence on the performance due to the dimensional variation of each part and the like, thereby improving the reliability and obtaining stable quality.

(Embodiment 4) Next, a fourth embodiment of the present invention will be described with reference to FIGS.

As shown in the figure, since the material 20 having good thermal conductivity is filled or inserted between the insulating material 9 and the heat sensitive plate 8, the temperature of the heat sensitive plate 8 is more reliably transferred to the temperature sensor 10. Conduction can be performed, and the temperature of the container 1 can be detected more accurately. In addition, when the temperature sensor 10 covered with the insulating material 9 is mounted between the U-shaped concave portion 7 provided at the lower portion of the heat-sensitive plate and the upper flat portion 6, the influence on performance due to assembly variation and the like is reduced, and the stability is reduced. Performance and quality can be obtained.

(Embodiment 5) Next, a fifth embodiment of the present invention will be described with reference to FIG.

As shown in the figure, since both ends 21 of the concave portion of the heat sensitive plate 8 in which the temperature sensor 10 and the insulating material 9 are inserted are caulked, the temperature sensor 10 and the insulating material 9 are closely attached to the heat sensitive plate 8. Thus, the temperature of the heat sensitive plate 8 can be more reliably conducted to the temperature sensor 10, and the temperature of the container 1 can be detected more accurately. In addition, processing variations can be suppressed, and the temperature sensor 10 and the heat-sensitive plate 8 covered with the insulating material 9 are treated as one unit, so that workability and assemblability can be improved.

(Embodiment 6) Next, a sixth embodiment of the present invention will be described with reference to FIG.

As shown in FIG.
2 through which lead 15 of temperature sensor 10 covered with
2 and a heat insulating portion 23 covering the entire outer peripheral portion of the heat sensitive plate 8 so as not to be easily affected by the radiant heat of the heating element and the fluctuation of the ambient room temperature, so that the temperature of the container 1 can be detected more accurately. Can be. Further, the leadability of the temperature sensor 10 is passed through the hole 22 provided in the cover 11 and integrated therewith, whereby the assemblability can be improved.

(Embodiment 7) Next, a seventh embodiment of the present invention will be described with reference to FIG.

As shown in the figure, the temperature sensor 10 is adhered and fixed between the insulating material 9 having good thermal conductivity and the cover 11 and is closely attached to the back side of the bottom surface of the container 1, so that the temperature of the container 1 can be more accurately measured. Can be detected. Further, the number of parts can be reduced, cost power can be enhanced, and assembling workability can be improved.

Although each of the above embodiments has been described using an electric water heater, it may be used for other electric equipment.

[0041]

As is clear from the above description of the embodiment, the present invention is made of a plate material in order to reduce the thermal mass of the heat-sensitive plate. A temperature sensor is mounted between the flat portions via an insulating material, and pressed against the bottom of the container, and the protrusion of the cover and the insulating material and the leads of the temperature sensor covered with the insulating material are placed on the heat sensitive plate side. Improves the adhesion between the temperature sensor and the heat sensitive plate by pressing and pressing, so that the temperature sensor can follow the temperature change of the container, and the temperature of the container and the temperature detected by the temperature sensor can be approximated. . Thus, the temperature can be detected by quickly following a rapid temperature change in the container, so that it is possible to improve the detection performance of boiling and empty cooking, to improve the corrosion resistance of the container, and to quickly cope with reheating.

Also, since the insulating material and the leads of the temperature sensor covered with the insulating material are brought into close contact with the lower part of the flat surface of the heat-sensitive plate by the projections provided on the cover, the temperature sensor follows the temperature change of the container. In addition, since the temperature of the container and the temperature detected by the temperature sensor can be more approximated, the influence on the characteristics due to fluctuations in ambient room temperature and the like can be reduced, and a stable high performance can be obtained.

Further, since the insulating material and the temperature sensor covered with the insulating material or the temperature sensor lead or both are filled or inserted with a material having good thermal conductivity, the heat dissipation from the temperature sensor is performed. Can be reduced, and the temperature of the heat sensitive plate and the temperature detected by the temperature sensor can be more approximated. In addition, it is possible to reduce the influence on the performance due to the dimensional variation of each part and the like, thereby improving the reliability and obtaining stable quality.

Further, since a material having good thermal conductivity is filled or inserted between the insulating material and the heat sensitive plate, the temperature of the heat sensitive plate can be more reliably conducted to the temperature sensor, and the temperature of the container can be more accurately measured. Can be detected. Also, when mounting the temperature sensor covered with insulating material between the U-shaped concave part provided at the bottom of the heat sensitive plate and the flat part at the top, the influence on the performance due to assembly variation etc. is reduced, and the stable performance and quality are reduced. Can be obtained.

Further, since both ends of the concave portion of the heat sensitive plate into which the temperature sensor and the insulating material are inserted are caulked, the adhesion between the temperature sensor and the insulating material and the heat sensitive plate can be improved, and the temperature of the heat sensitive plate can be increased. Heat can be reliably transferred to the temperature sensor, and the temperature of the container can be detected more accurately. In addition, processing variations can be suppressed, and the workability and assemblability can be improved by treating the temperature sensor and the heat sensitive plate covered with the insulating material as one unit.

Further, the cover is provided with a hole for passing the lead of the temperature sensor covered with an insulating material, and a heat insulating portion is provided to cover the entire outer peripheral portion of the heat-sensitive plate. Since the temperature of the container is reduced, the temperature of the container can be detected more accurately. Further, the leadability of the temperature sensor is passed through a hole provided in the cover to be integrated, thereby improving the assemblability.

Further, since the temperature sensor is adhered and fixed between the insulating material having good thermal conductivity and the cover and is adhered to the back side of the bottom surface of the container, the temperature of the container can be detected more accurately.

Further, the number of parts can be reduced, the cost power can be enhanced, and the assembling workability can be improved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a temperature detecting device of an electric water heater according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the electric water heater.

FIG. 3 is a schematic sectional view of a temperature detecting device of the electric water heater.

FIG. 4 is an exploded perspective view of the electric water heater according to the second and third embodiments.

FIG. 5 is a sectional view of the electric water heater of the second to fourth embodiments.

FIG. 6 is a perspective view of the electric kettle of the fifth embodiment.

FIG. 7 is an exploded perspective view of the electric water heater of the sixth embodiment.

FIG. 8 is an exploded perspective view of the electric water heater of the seventh embodiment.

FIG. 9 is a sectional view of the electric water heater of the seventh embodiment.

FIG. 10 is a schematic sectional view of a conventional electric water heater.

FIG. 11 is an exploded perspective view of the temperature detector of the electric water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Outer body 3 Heating element 5 Temperature detector 6 Flat part 7 U-shaped recess 8 Heat sensitive plate 9 Insulating material 10 Temperature sensor 11 Cover 13 Mounting spring 14 Projection part 15 Lead part of temperature sensor 16 Control board 17 Below flat part Method 18 Good thermal conductive material 21 Both ends of concave portion 22 Hole 23 Heat insulating part 24 Good thermal conductive insulating material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-224709 (JP, A) JP-A 64-8926 (JP, A) JP-A-3-125824 (JP, A) 109031 (JP, U) JP-A 3-111227 (JP, U) JP-A 62-197237 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) A47J 27/21 101

Claims (7)

(57) [Claims] 1. A bottomed cylindrical container provided in an exterior body, a heating element fixed on the back side of the bottom surface of the container, a temperature detecting device mounted on the back side of the bottom of the container, and an electric signal from the temperature detecting device. It consists of a control board that controls the energization of the heating element by a signal, and the temperature detecting device is a plate-shaped heat-sensitive plate having a flat portion at the top and a U-shaped recess at the bottom, and an insulating material in the recess It consists of a mounted temperature sensor and a cover that covers the periphery of the recess with a gap between the recess and the mounting and fixing of the heat-sensitive plate placed on the cover with a mounting spring that presses and biases the bottom of the container via the cover. An electric water heater in which a projection provided on a cover presses and biases the insulating material and a lead portion of the temperature sensor covered with the insulating material toward the heat-sensitive plate. 2. An electric water heater according to claim 1, wherein said insulating material and a lead portion of a temperature sensor covered with said insulating material are brought into close contact with a flat portion of said heat-sensitive plate below said projecting portion provided on said cover. 3. The electric water heater according to claim 1, wherein at least one of an insulating material, a temperature sensor covered with the insulating material, and a lead portion of the temperature sensor is filled or inserted with a material having good thermal conductivity. 4. The electric water heater according to claim 1, wherein a material having good thermal conductivity is filled or inserted between the insulating material and the heat sensitive plate. 5. The electric water heater according to claim 1, wherein both ends of the concave portion of the heat sensitive plate into which the temperature sensor and the insulating material are inserted are caulked. 6. The electric water heater according to claim 1, wherein the cover is provided with a hole for passing a lead portion of the temperature sensor covered with an insulating material, and a heat insulating portion is provided to cover the entire outer peripheral portion of the heat sensitive plate. 7. The electric water heater according to claim 1, wherein the temperature sensor is adhered and fixed between the insulating material having good thermal conductivity and the cover.