JPS5940891Y2 - electric water heater - Google Patents

Description

[Detailed description of the invention] The present invention relates to an electric water heater equipped with a submersible heating element, and in particular, provides a water heater that is extremely easy to attach the submersible heating element to a container, and is safe and inexpensive. It is.

Conventionally, to attach a submersible heating element to a container, a threaded brass fitting that is incorporated into the submersible heating element through a backing is inserted into a hole in the bottom of the container. It was maintained watertight by tightening nuts to the mounting bracket of the type heating element along with the metal fittings for attaching the thermostat and temperature fuse.

Therefore, when boiling water or when cooking without putting anything to be heated in the container, the heat of the submersible heating element is directly transferred to the backing, or via the submersible heating element's attachment to the mounting bracket or its mounting bracket. It was transmitted to the installed thermostat and temperature fuse.

However, since the fittings are made of brass and have a high degree of cutting,
Thermal conductivity was good, and the heat was transferred to the thermostat and temperature fuse more than necessary, making temperature control difficult and complicated.

In other words, when boiling water, the thermostat installed outside the container cannot properly control the water temperature because it is too influenced by the heating element, and it is also greatly affected by changes in the applied voltage, resulting in poor water temperature control performance. Ta.

Furthermore, the temperature of the temperature fuse is quite high even during normal boiling water due to the influence of the heating element, so a temperature fuse with a high melting temperature must be used.

Furthermore, when the temperature fuse blows during an abnormality, the temperature of the temperature fuse is quite high, so the temperature of other parts also rises to a considerably high temperature, which is dangerous, and many parts become unusable and must be reused. There are many parts that need to be replaced,
It was uneconomical.

In addition, brass screws and nuts have recently become extremely expensive due to rising material and processing costs, causing increased product costs.

The present invention solves the above-mentioned conventional drawbacks, and embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In the figure, 1 is a container, which has a spout on the upper side, a screw on the outer periphery of the lower part, and a through hole 1a on the bottom surface.

2 is a submersible type heating element, which has a round plate shape with a bulge in the center and is made of stainless steel with an upper seam plate 2a and a heat generating material 2b made of a mica plate with a heat generating wire wound around it. A heat generating member 2e sandwiched between upper and lower insulating materials 2c and 2d such as plates, each having a through hole in the center, a heat shield plate 2f having a through hole in the center, and a stepped through hole in the center. A round plate-shaped lower seam plate 2g having a round plate shape, a flange portion 2h that engages with a stepped through hole of the lower seam plate 2g and is fixed by spot welding, etc., a through hole 21, and an outwardly convex or concave stepped portion. The lead wire 2 of the heat generating member 2e is led out from a through hole 21 in the mounting member 2.

The submersible heating element 2 is connected to a container connecting plate 4 through a backing 3 made of heat-resistant silicone rubber or the like to the through hole 1a of the container 1.
A buffer rubber backing 5, a body stopper/temperature fuse mounting bracket 6, a wave spring washer 7, and a flat washer 8 are stacked one after another on the outer surface of the container 1, and a retaining ring 9, which has a plurality of claws on the inner periphery and has spring properties, is submerged. The retaining ring 9 is press-fitted to the mounting member 2k of the type heating element 2, and the retaining ring 9 is attached to the inner bottom of the container 1 in a water-tight manner by engaging the claws of the retaining ring 9 to the stepped portion 2j of the mounting member 2.

Reference numeral 10 denotes a body, which is provided with a screw on the upper inner side and is fastened to the threaded portion of the container 1.

Reference numeral 11 denotes a back plate, which is arranged at the bottom of the body 10 and fixed with screws.

12 is a cord plug, 13 is a handle, and 14 is a lid.

Next, the effects of the above configuration will be explained.

Since the submersible heating element 2 is watertightly attached to the container 1 using the retaining ring 9 as described above, it can be attached more easily than the conventional screw type, and the attachment member 2 can be formed by simple machining of a pipe. This allows for significant cost reductions.

Furthermore, a mounting member 2k made of austenitic stainless steel (SUS304) with good workability is spot welded to the lower seam plate 2g made of ultra-low carbon ferritic stainless steel with excellent corrosion resistance, and the material of the lower seam plate 2g changes during welding. There is no deterioration in corrosion resistance.

In addition, since SUS 304 is used for the mounting member 2k, it has much less heat conduction than conventional brass, making it easier to control the temperature when boiling water or in the event of an abnormality.
Moreover, it is possible to supply a reliable, safe and economical water heater.

That is, when boiling water, the thermostat installed outside the container operates correctly without being affected by voltage changes, and the temperature of the temperature fuse is low, so a temperature fuse with a low blowout temperature can be installed.

Therefore, when the temperature fuse blows in an abnormal situation, the temperature of each part is not so high and there is no damage to each part.
There is no risk of fire or the like, and it can be used again.

As is clear from the above explanation, according to the present invention, the submersible heating element can be easily attached to the container using the retaining ring.
In addition to improving assembly workability, the mounting parts can be made of materials with poor thermal conductivity, making it easier and more reliable to control the temperature during abnormal situations such as boiling water or empty cooking, making it possible to create a safe and inexpensive electric water heater. can be provided.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway sectional view of an electric water heater showing an embodiment of the present invention, Fig. 2 is an exploded perspective view of the same essential parts, and Fig. 3 is a submersible heating element of the electric water heater. A partially cutaway sectional view and FIG. 4 are back views of the underwater heating element. 1... Container, 2... Submersible heating element, 2
a... Upper seam plate, 2b... Heat generating material,
2c... Upper insulating material, 2d... Lower insulating material, 2g... Lower seam plate, 2k... Mounting member, 3...... Backing, 7...Wave spring washer, 8...Flat washer, 9...Retaining ring.

Claims (1)

[Scope of utility model registration request] A submersible heating element is constructed by sequentially laminating a lower seam plate with a mounting member, a heat generating material sandwiched between heat-resistant insulating materials, and an upper seam plate, and the mounting member is attached to a heat-resistant backing and a bottomed container. , a spring washer, a flat washer, and an elastic retaining ring with claws formed on the inner periphery are sequentially inserted, and the claws of the retaining ring are engaged with the outer peripheral surface of the mounting member to attach the submersible heating element to the container. An electric water heater that is kept watertight.