JP5646930B2 - Water heater - Google Patents

Description

  The present invention relates to a water heater for boiling water in a container.

  Conventionally, a water heater using a thermal fuse is known as a method of shutting off the power supply in the case of abnormal malfunction such as when performing continuous water heating (for example, Patent Document 1).

  Further, in order to enhance the heat retaining effect of the liquid boiled in the container, a method of sealing the opening of the container with a silicone-based packing material is employed (for example, Patent Document 2).

JP 2003-93233 A JP 2002-369747 A

  In the above prior art, for example, when a temperature fuse of 152 ° C. and 157 ° C. is used, it takes about 3 minutes until the temperature fuse is blown at the time of abnormality. In this case, if a temperature fuse with a lower operating temperature is used, the temperature fuse operates even during normal boiling, and if the mounting position of the temperature fuse is changed to the heating body side, the temperature fuse reaches around 250 ° C. It will be out of use range in terms of temperature. In addition, if only the heat of the heating body is drawn into the thermal fuse, the operation time at the time of abnormality is further increased, which is not preferable.

  Therefore, when a limiter is used instead of the thermal fuse, the heat source can be directly in contact with the limiter without using an insulator, and the temperature fluctuation of the heat source can be quickly picked up and the operation can be quickly performed. In addition, the operating temperature can be set to a high temperature of 240 ° C. to 270 ° C., and it can cope with the heat of the heating body during normal times.

  However, when the limiter is directly attached to the heating element, the limiter reaches around 300 ° C. and operates during normal boiling, so that a structure for picking up heat from the heating element only in an abnormal state and operating the limiter reliably is required. It was.

  Accordingly, a first object of the present invention is to provide a water heater that picks up heat from a heating element only at the time of abnormality and operates the limiter with certainty.

According to the first aspect of the present invention, the backlash of the limiter due to the variation of the second presser body can be suppressed by pressing the limiter and fixing it to the cover using the spring property of the second presser body. In addition, the heat transferred from the heating body to the first presser body in this state is collected by the heat collecting body and transmitted to the limiter, so that the heat from the heating body can be transferred only in an abnormal state without attaching the limiter directly to the heating body. It is possible to pick up and operate the limiter reliably. In addition to the simple structure that only provides a flange on the cover, the limiter can be fixed to the cover without rattling, and the temperature of the liquid in the container is normally communicated via a heat receiver to operate the limiter. It can be prevented from rising up to.

  According to the first aspect of the present invention, it is possible to provide a water heater that picks up heat from the heating element only at the time of abnormality and operates the limiter reliably.

Further, the limiter can be fixed to the rattling without covering by a simple structure, it can be further during normal, so as not to increase the limiter to the operating temperature.

It is the principal part bottom view seen from the container back surface of the water heater in one Example of this invention. It is a principal part longitudinal cross-sectional view of the state which turned the water heater upside down same as the above. It is the principal part longitudinal cross-sectional view seen from another direction of the state which turned the water heater upside down same as the above. It is a principal part perspective view of a limiter and its periphery same as the above. It is a principal part perspective view of the state which removed the heater presser cover seen from the container back surface same as the above. It is the figure which showed the container cross section typically same as the above. It is the figure which showed the container cross section in a prior art typically.

  Hereinafter, preferred embodiments of a water heater according to the present invention will be described with reference to the accompanying drawings. 2 and 3 both show a state in which the water heater is turned upside down, the lower part of the figure corresponds to the upper part of the water heater, and the upper part of the figure corresponds to the lower part of the water heater.

  In each figure of FIGS. 1-5, 1 is a bottomed container which stores the water which is a liquid inside, this container 1 stands | starts up vertically from the baseplate 2 which forms a bottom part, and the periphery of the baseplate 2, It is comprised by the cylinder part 3 which forms the side part of the container 1. FIG. A recess 4 is formed in the bottom plate 2 when viewed from the outside, and a flat heater 5 as a heating body for heating the liquid in the container 1 is accommodated in the recess 4. The recess 4 is formed at the center of the bottom plate 2 when viewed from the bottom of the container 1, and the ring-shaped outer peripheral portion 6 around the recess 4 forms the bottom surface of the container 1.

  Reference numeral 11 denotes a heater press that is in close contact with the lower side of the heater 5 and diffuses heat from the heater 5. Here, the heater press 11 is attached and fixed to the bottom of the bottom plate 2 so as to cover the heater 5. As shown in FIG. 2, the heater presser 11 protrudes downward from the end portion of the flat plate portion 12 to a flat plate portion 12 formed in conformity with the shape of the bottom outer surface of the container 1 and a portion not in close contact with the heater 5. And an L-shaped bent portion 13 formed. And the screw hole 16 for screwing the screw | thread 15 mentioned later in the horizontal lower end part of the bending part 13 is formed.

  Reference numeral 18 denotes a heat receiving plate which is provided so as to cover the flat plate portion 12 of the heater presser 11 and is made of a member having good heat conductivity such as aluminum. The heat receiving plate 18 includes a heat receiving portion 19 that is in close contact with the flat plate portion 12 of the heater retainer 11 to which the heater 5 is attached, and a heat radiating portion 20 that is separated from the flat plate portion 12 and guides the heat received by the heat receiving portion 19 to another member. It consists of. A plate-shaped heat collecting plate 21 smaller than the heat receiving plate 18 is provided below the heat radiating unit 20, and the heat receiving surface of the cylindrical limiter 31 is in close contact with the lower surface of the heat collecting plate 21. .

  As shown in FIG. 3, in a portion where the heater presser 11 does not cover the heater 5, the heat receiving portion 19 of the heat receiving plate 18 may be directly adhered to the lower side of the heater 5. In this case, the heat radiating portion 20 of the heat receiving plate 18 is extended so as to be away from the heater 5 and in contact with the outer peripheral portion 6 of the container 1, and the heat collecting plate 21 is provided below the heat radiating portion 20.

  The heat collecting plate 21 is formed with a cut-and-raised portion 22 as an engaging portion in a shape that engages with the outer shape of the limiter 31. The cut-and-raised part 22 is for preventing the heat collecting plate 21 from being detached from the limiter 31. The shape of the cut-and-raised part 22 may be appropriately changed in accordance with the outer shape of the limiter 31 as long as the same function can be exhibited. Similar to the heat receiving plate 18, the heat collecting plate 21 is made of a member having good thermal conductivity such as aluminum, for example, so that the heat from the heater holder 11 can be easily transmitted to the limiter 31.

  The limiter 31 is provided as an overheat prevention device that operates when the temperature of the water heater rises abnormally and cuts off the power supply to the heater 5. Unlike a conventional temperature fuse, an insulator such as a silicone tube is wound around the limiter 31. The heat receiving surface can be directly attached to the lower surface of the heat collecting plate 21 without mounting. Further, a step portion 32 is formed on the outer surface of the limiter 31.

  Reference numeral 36 denotes a heater press cover which is attached to the lower side of the heater press 11 with the screw 15. The heater pressing cover 36 also serves as a mounting plate for the electric pump 37 that sends the liquid in the container 1 to a discharge port (not shown). By providing the heater pressing cover 36 at the bottom of the electric pump 37, the heater pressing cover 36 is provided. When the presser cover 36 is attached to the lower side of the heater presser 11, the electric pump 37 is attached and fixed to the bottom of the container 1. The flat heater presser cover 36 is formed with an opening 38 for the screw 15 and an insertion portion 39 for inserting a limiter presser plate 41 to be described later.

  Reference numeral 41 denotes a limiter pressing plate for mounting and fixing the limiter 31 to the heater pressing cover 36. The limiter pressing plate 41 includes a base 42 that contacts the lower surface of the heater pressing cover 36, a protruding piece 43 that extends upward from one end of the base 42, and whose tip is inserted into the insertion portion 39 of the heater pressing cover 36, An L-shaped elastic piece 44 that extends from the other end of the base portion 42 toward the limiter 31 side and abuts against the stepped portion 32 so as to press the heat receiving surface of the limiter 31 against the heat collecting plate 21, The bent portion extends from the bent portion toward the bottom of the container 1, and the tip of the bent portion 45 is constituted by another protruding piece 45 that comes into contact with the heat collecting plate 21.

  The base portion 42 of the limiter pressing plate 41 is fixedly attached to the heater pressing cover 36 with the protruding piece 43 inserted into the insertion portion 39, and the screw portion of the screw 15 passes through the insertion hole 38 of the heater pressing cover 36. By screwing this threaded portion into the screw hole 16 of the heater retainer 11, the heater retainer cover 36 is attached and fixed to the heater retainer 11, and the limiter retainer plate 41 is interposed between the heater retainer cover 36 and the heater retainer 11. Mounted in position. At this time, the elastic piece 44 of the limiter pressing plate 41 abuts on the stepped portion 32 of the limiter 31 and applies a force that presses the heat receiving surface located on the uppermost surface of the limiter 31 against the lower surface of the heat collecting plate 21. Therefore, even if the limiter pressing plate 41 has some dimensional variation, the limiter 31 can be brought into close contact with the heat collecting plate 21 without rattling. Further, by inserting the protruding piece 43 of the limiter pressing plate 41 into the insertion portion 39 of the heater pressing cover 36, the limiter pressing plate 41 is positioned with respect to the heater pressing cover 36, and the limiter 31 of the heat collecting plate 21 is also positioned. Since the cut-and-raised portion 22 that can be locked to the side portion is provided, it is possible to restrict the movement of the limiter 31 particularly in the horizontal direction and attach the limiter 31 to the heat collecting plate 21 without rattling. .

  As shown in FIG. 1, limiters 31 are provided at a plurality of locations on the bottom of the container 1, and when any one of the limiters 31 detects an abnormal temperature of the water heater, the energization to the heater 5 is cut off. The heat collecting plate 21 and the limiter pressing plate 41 are provided corresponding to the respective limiters 31. Of course, the limiter 31 may be one. Reference numeral 47 denotes an electrical connection terminal connected to the heater 5.

  In the above configuration, the heater 5 is controlled to be cut off by a control means (not shown), whereby the container 1 and thus the liquid in the container 1 can be heated and boiled (boiling), and kept at a predetermined temperature. In this series of operations, the heat diffused from the heater 5 to the heater retainer 11 is quickly guided from the heat receiving portion 19 of the heat receiving plate 18 to the heat radiating portion 20, and the heat collecting plate 21 thermally connected to the heat radiating portion 20 The heat is collected and led to the limiter 31. The limiter 31 is attached and fixed to the heater pressing cover 36 by the limiter pressing plate 41, and is pressed against the heat collecting plate 21 by the spring force of the elastic piece 44 formed in a plate shape. The heat guided to can be detected with high sensitivity.

  The limiter 31 here is not directly attached to the heater 5, and a part of the heat diffused by the heater holder 11 is guided from the heat receiving plate 18 to the heat collecting plate 21 and picked up by the limiter 31. In addition, since a part of the heater presser 11 is in direct contact with the container 1, the temperature of the heat collecting plate 21 is suppressed under the influence of the liquid temperature in the container 1 in a normal water heater, and the limiter 31 does not malfunction. . However, if the heater 5 is energized in a state where no liquid is present in the container 1 by continuously boiling the water or the like, the container 1 becomes above the boiling temperature of the liquid. The temperature rises by picking up only the heat, and the limiter 31 operates to cut off the power supply to the heater 5 quickly. In the structure of the safety device in the present embodiment, the operation time at the time of abnormality is less than 2 minutes, and the damage to the container 1 can be drastically reduced.

  Next, the structure of the container 1 is demonstrated based on FIG. The container 1 has a heat insulating structure in which a vacuum space 53 that is depressurized from the atmospheric pressure is provided between the inner layer 51 and the outer layer 52, and has a bottomed cylindrical body portion 54 that contains liquid, and an upper portion of the body portion 54. For example, a circular opening 55. Reference numeral 56 denotes a cylindrical insertion part that closes the opening 55, and its outer surface has a shape that matches the side of the opening 55. One or a plurality of recesses 57 are formed on the outer surface of the insertion part 56, and an O-ring 58 made of silicone rubber is engaged with the recesses 57. The outer end of the O-ring 58 is positioned slightly outward from the outer surface of the insertion part 56. When the insertion part 56 is inserted into the opening 55, the O-ring 58 is elastically deformed and the opening An O-ring 58 is in close contact with the inner surface of 55. In addition, although the container 1 shown in FIG. 1 becomes the structure which joined the baseplate 2 and the cylinder part 3, it may replace with this and may use the container 1 of a double heat insulation structure as shown in FIG.

  Here, for comparison, the configuration of a conventional container 1 'is shown in FIG. In the figure, reference numeral 61 denotes a packing which is attached to a lid assembly (not shown) and is in close contact with the inner surface of the opening 55 when inserted into the opening 55. The packing 61 is made of silicone rubber rich in elasticity, like the O-ring 58, but the cross section is formed in a U shape in accordance with the inner surface of the opening 55.

  Comparing FIG. 6 with FIG. 7, the container 1 of the present embodiment has an opening 55 smaller than the conventional container 1 ′, and its inner diameter R1 is formed to be less than half of the inner diameter R2 of the body part 54. The escape of heat from the portion 55 is minimized. Further, an O-ring 58 is mounted around the side surface of the insertion part 56 that can be attached to and detached from the opening 55, and the insertion part 56 is inserted into the opening 55 while being elastically deformed by pressing the O-ring 58 against the inner surface of the opening 55. Thereby, the sealing performance of the insertion part 56 with respect to the opening part 55 can be improved, and between the opening part 55 can be reliably sealed over the perimeter of the insertion part 56, and the temperature fall of the liquid in the container 1 is suppressed. In addition, it is possible to suppress the warming power accompanying the interruption of the heater 5.

  As described above, the water heater of the present embodiment includes a container 1 for storing water, which is a liquid, a heater 5 as a heating body attached to the bottom plate 2 forming the bottom of the container 1, and a heater 5 for pressing the heater 5 toward the container 1 side. A heater presser cover is provided by a heater presser 11 as a first presser, a heater presser cover 36 as a cover fixed to the heater presser 11 by a screw 15 as a fastening member, and a limiter presser plate 41 as a second presser. The limiter 31 is fixed to 36, and the heat collecting plate 21 as a heat collecting body for concentrating heat to the limiter 31.

  In this case, the limiter presser plate 41 is pressed against the heat collecting plate 21 and fixed to the heater presser cover 36 by using the spring property of the limiter presser plate 41, particularly the elastic piece 44 that contacts the limiter 31. The rattling of the limiter 31 due to the variation can be suppressed. Further, in this state, the heat transmitted from the heater 5 to the heater presser 11 is collected by the heat collecting plate 21 and transmitted to the limiter 31, so that the limiter 31 is not directly attached to the heater 5, but only from the heater 5 at an abnormal time. The limiter 31 can be reliably operated by picking up heat.

  Further, the limiter 31 in the present embodiment is fixed to the heater pressing cover 36 by an insertion portion 39 as a flange portion provided in the heater pressing cover 36, and is positioned between the heat collecting plate 21 and the container 1. 5 and a heat receiving plate 18 as a heat receiving body that receives heat from the container 1 at the same time.

  In this case, the limiter 31 can be fixed to the heater pressing cover 36 without rattling with a simple structure in which the insertion portion 39 is provided in the heater pressing cover 36. In addition, the liquid in the container 1 is normally connected via the heat receiving plate 18. By transmitting this temperature, it is possible to prevent the limiter 31 from being raised to the operating temperature.

  Further, in the water heater of the present embodiment, the opening 55 of the container 1 into which the liquid is put is formed smaller than the conventional one, and an O-ring 58 made of silicone rubber is mounted around the insertion part 56 into the opening 55. The opening 55 is sealed by the O-ring 58.

  Accordingly, by reducing the opening 55 of the container 1, heat radiation from the opening 55 is reduced, and the silicone rubber O-ring 58 is used instead of silicone rubber (packing 61) having a U-shaped cross section. Thus, the sealing performance is improved, and the space between the opening 55 is securely sealed over the entire circumference of the insertion part 56, so that the temperature drop of the liquid in the container 1 can be suppressed and the heat retaining power can be suppressed. .

  In addition, this invention is not limited to said each Example, A various deformation | transformation implementation is possible. For example, a member other than the screw 15 may be used as the fastening member, and the heater retainer 11, the heat collecting plate 21, the heater retainer cover 36, and the limiter retainer plate 41 are within the scope of the present invention. The shape, material, etc. can be changed as appropriate.

1 container 5 heater (heating body)
11 Heater presser (first presser)
15 Screw (fastening member)
18 Heat receiving plate (heat receiving body)
21 Heat collector (heat collector)
31 Limiter 36 Heater presser cover (cover)
39 Insertion part (flange part)
41 Limiter presser plate (second presser body )

Claims (1)

A container for liquid,
A heating element attached to the bottom of the container;
A first presser body for pressing the heating body;
A cover fixed to the first pressing body by a fastening member;
A limiter fixed to the flange portion of the cover by a second presser;
A water heater , comprising: a heat collector that collects heat in the limiter; and a heat receiver provided between the heat collector and the container .

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