JPH1014769A - Electric hot water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform maintenance such as washing by forming flat the bottom surface of an inner vessel concerning an electric hot water heater for which a heating device is fitted on the bottom surface of this inner vessel. SOLUTION: A bottom member 31 of an inner vessel 21 is formed from a peripheral edge part 32 fixed at the lower end of a body part 29, intermediate peripheral edge part 33 continued to the peripheral edge part 32 and flat bottom part 34 and, by forming the intermediate peripheral edge part 33 to be curved with a small diameter on the side of flat bottom part 34, ruggedness at the bottom part of inner surface of the inner vessel 21 can be eliminated while securing the required rigidity of the flat bottom part 34.

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, and more particularly to a structure for mounting a heating device.

[0002]

2. Description of the Related Art There has been known an electric water heater in which a heating device is mounted on the bottom of an inner container and the inner container is housed in an outer container. FIG. 5 and FIG. 6 are examples, and these drawings show a mounting structure of the heating device 2 to the inner container 1.

The bottom of the inner container 1 is formed by fixing a peripheral portion 5 of a bottom member 4 separate from the body 3 to a lower end of the body 3. In the bottom member 4, an outer peripheral flat portion 6 having a required width is formed inside the peripheral portion 5, and a stepped portion 7 having a required shape is formed inside the outer peripheral flat portion 6. The inside is a flat bottom 8. A heating element 9 having a shape matching the shape of the stepped portion 7 is fitted and adhered to the flat bottom portion 8.

[0004] The holding member 10 of the heating element 9 has a step 11 along the step pushing portion 7, and an outer peripheral flange 12 formed on the outer periphery of the step 11 is connected to the outer peripheral flat portion 6.
And is projection-welded at required intervals. Further, a flat portion formed inside the step portion 11 serves as a pressing surface 13, and the pressing surface 13 serves as the step pressing portion 7.
And presses down the heating element 9.

[0005] At the center of the flat bottom 8 is an inner container 1.
Are protruded inward, and the protrusions 14
Corresponding to the circular hole 1 in the heating element 9 and the holding member 10.
5 and 16 are provided, and a temperature sensor (not shown) is inserted into the lower surface of the projection 14 through the holes 15 and 16. An inner peripheral flange 20 is formed on the inner periphery of the hole 16 of the holding member 10, and the portion of the inner peripheral flange 20 is also projection-welded around the protrusion 14.

[0006] In addition, in the figure, 17 is a water supply port welded to the outer peripheral flat portion 6, 18 is a mounting leg, and 19 is a lead wire.

[0007]

Since the heating device 2 in the conventional electric water heater is configured as described above, the upper surface of the flat bottom portion 8 is provided on the inner bottom surface of the inner container 1 with the stepping portion 7. It has an appearance shape in which it protrudes inward by the height and a protruding portion 14 appears at the center of the flat bottom portion 8.

The flat bottom 8 rises at a position closer to the inside by the width of the outer flat portion 6 from the inner circumferential surface of the body 3. For this reason, when the inside is to be cleaned, the rising portion of the stepped portion 7 and the gap corresponding to the width of the outer peripheral flat portion 6 are difficult to reach because fingertips, brushes, and the like are difficult to reach. Further, there is also a disadvantage that the protruding shape of the flat bottom portion 8 occupying a wide area impairs the appearance.

Further, in the case of performing a sandblasting process as a base treatment when the inner surface of the inner container 1 is subjected to a fluorine surface treatment or a spray coating process from a top opening of the inner container 1 in a paint coating process, a step is required. There is a part where the spraying does not reach (a so-called shadow part) at the rising part of the pressing part 7, and there is a problem that it is difficult to uniformly treat the entire bottom surface.

As described above, the stepping process of the bottom member 4 increases the rigidity of the flat bottom portion 8 on which the heating device 2 is mounted, imparts a sufficiently high flatness to the flat bottom portion 8, and makes the heating element 9 adhere well. This is because For this reason, step-pressing has conventionally been considered to be indispensable. However, when step-pressing is performed, the above-described problems occur.

Accordingly, the present invention provides a liquid container in which a heating device is attached to the lower surface of a bottom member of an inner container, in which the flatness of the flat bottom of the bottom member is maintained sufficiently high without stepping, and the flatness is maintained. The purpose is to ensure the adhesion between the bottom and the heating element.

[0012]

In order to achieve the above object, the present invention relates to an electric water heater having a heating device mounted on a bottom surface of an inner container and housing the inner container in an outer container. The bottom portion of the inner container is formed by fixing a bottom member separate from the body portion, and the bottom member is fixed to the lower end of the body portion, and is continuously connected to the lower edge of the lower portion and below the lower portion. An intermediate peripheral portion protruding from the intermediate peripheral portion, and a flat bottom formed at the lower end of the intermediate peripheral portion. The intermediate peripheral portion is formed in a curved shape or a tapered shape in which the flat bottom portion has a small diameter, and The heating device is mounted on the lower surface of the bottom.

[0013]

According to the above construction, since the bottom member is reinforced by the presence of the intermediate peripheral portion, the flat bottom portion maintains a high flatness, thereby improving the adhesion to the heating element.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, the electric water heater of the embodiment is one in which a heating device 22 is attached to a bottom surface of an inner container 21, and the inner container 21 is stored in an outer container 23. A lid 24 is attached to the outer container 23 so as to be openable and closable, and an electric pump 27 is attached between a water supply port 25 provided on the bottom surface of the inner container 21 and a water supply pipe 26. Hot water is discharged.

The inner container 21 is, as shown in FIG.
It is formed by the body 29 and the bottom member 31. Bottom member 31
Is a peripheral portion 32 fixed to the lower peripheral portion of the body portion 29 by welding, an intermediate peripheral portion 33 continuously projecting downward from the peripheral portion 32, and a flat bottom portion 34 formed at the lower end of the intermediate peripheral portion 33. And

The intermediate peripheral portion 33 has a smaller diameter at the lower end on the flat bottom portion 34 side than at the upper end on the peripheral portion 32 side, and the cross-sectional shape of that portion is curved. It is formed as follows. Instead of being formed in a curved shape, it may be formed in a tapered shape. By forming such an intermediate peripheral portion 33, the rigidity of the flat bottom portion 34 is improved, and high flatness is obtained.

A projection 35 is formed at the center of the flat bottom 34 so as to project inwardly of the inner container 21, and the temperature sensor 36 is brought into contact with the lower surface thereof (see FIG. 1). Further, the water supply port 25 is press-formed at a portion approaching the intermediate peripheral portion 33.

As shown in FIGS. 3 and 4, the heating device 22 includes a heating element 37 and a pressing member 38 thereof. The heating element 37 is a planar element generally called a space heater, and further provided with an insulating plate inside the insulating plate 40.
A heating wire is wound around the insulating plate, and this is
9. The above aluminum plate 39
Has an outer peripheral shape mounted on the lower surface of the flat bottom portion 34 inside the intermediate peripheral portion 33.

The water supply port 2 is provided at one side of the heating element 37.
The notch 30 corresponding to No. 5 is formed. In the central portion of the heating element 37, a hole 4 matching the above-mentioned projection 35 is provided.
1 are formed, and temporary fixing claws 42 are provided at two positions opposite to the outer peripheral portion of the aluminum plate 39.

The pressing member 38 has a cover surface 43 for covering the heating element 37 and an outer peripheral flange provided with a step corresponding to the thickness of the heating element 37 on the outer peripheral edge. The outer peripheral flange 44 is separated into small pieces by slits 45 formed at appropriate intervals. A notch 3 of the heating element 37 is provided on one side of the holding member 38.
A notch 30 'corresponding to zero is provided.

A hole 46 corresponding to the projecting portion 35 is provided at the center of the cover surface 43, and an inner peripheral edge of the hole 46 is provided with an inner peripheral flange 47 through a step corresponding to the thickness of the heating element 37.
And a required number of slits 48
Is separated into small pieces.

Appropriate positions of the outer peripheral flange 44 and the inner peripheral flange 47 separated by the slits 45 and 48 are fixed to the flat bottom 34 by projection welding.

The reason why slits 45 and 48 are provided in the outer peripheral flange 44 and the inner peripheral flange 47 to separate them into a large number of small pieces is that the flexibility of the heating element 3 is increased.
The thickness of the holding member 38 is absorbed by the unevenness of the thickness of the holding member 7 and the thermal deformation of the holding member 38.
This is to dissipate the heat accumulated inside.

The cover surface 43 is provided with a lead-out hole 51 for a lead wire 49 of the heating element 37. Further, the mounting leg 52 and the heating element 3
7 is an engagement recess 5 for engaging the temporary fixing claw 42
3 are provided.

The electric water heater of the embodiment is as described above, and is used in the state of a product as shown in FIG.
As usual, water is poured into the inner container 21, the hot water is boiled by energizing the heating device 22, the electric pump 27 is driven by an external switch operation, and the hot water is discharged from the discharge port 28.

When the inside of the inner container 21 is to be cleaned, a hand, a brush or the like is put in the inner container 21 for cleaning. At this time, the bottom surface of the inner container 21 has only the protrusion 35 at the center of the flat bottom 34, and there is no protrusion or narrow portion near the inner peripheral surface of the body 29, so that the bottom of the inner container 21 extends to every corner. It can be cleaned cleanly.

[0027]

As described above, according to the present invention, the rigidity of the flat bottom portion is increased by providing the curved or tapered intermediate peripheral portion at the peripheral portion of the bottom member, and the flatness is maintained at a high level. be able to. Therefore, adhesion between the flat bottom and the heating element can be ensured. Furthermore, the portion along the peripheral edge of the bottom surface of the inner container is flat over a wide area due to the presence of the flat bottom portion, so that care is easy and the appearance is good, and various spraying processes at the time of production can be uniformly applied. .

Further, since it is not necessary to match the shape of the heating element with the shape of the stepped portion as in the prior art, it is possible to use heating elements of various shapes according to the purpose of use.

[Brief description of the drawings]

FIG. 1 is a partially omitted cross-sectional view of an embodiment.

FIG. 2 is a partially omitted cross-sectional view of the inner container according to the first embodiment;

FIG. 3 is a perspective view of a bottom portion of the inner container according to the first embodiment;

FIG. 4 is an exploded perspective view of FIG. 3;

FIG. 5 (a) is a perspective view of a bottom portion of a conventional inner container, and FIG. 5 (b) is a sectional view of FIG.

FIG. 6 is an exploded perspective view of a bottom portion of a conventional inner container.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Inner container 22 Heating device 23 Outer container 24 Cover 25 Water supply port 26 Water supply pipe 27 Electric pump 28 Discharge port 29 Body part 30, 30 'Notch 31 Bottom member 32 Peripheral part 33 Intermediate peripheral part 34 Flat bottom part 35 Projection part 36 Temperature Sensor 37 Heating element 38 Pressing member 39 Aluminum plate 40 Insulating plate 41 Hole 42 Temporary fixing claw 43 Cover surface 44 Outer flange 45 Slit 46 Hole 47 Inner flange 48 Slit 49 Lead wire 51 Lead-out hole 52 Mounting leg 53 Engagement recess

Claims (1)

[Claims] 1. An electric water heater having a heating device mounted on a bottom surface of an inner container and housing the inner container in an outer container, wherein the bottom of the inner container is a bottom member separate from the body of the inner container. The bottom member is formed at the lower end of the intermediate peripheral edge portion which is fixed to the lower end of the body portion, the intermediate peripheral edge portion continuously protruding below the peripheral edge portion, and protruding downward from the peripheral edge portion. An electric wire, wherein the intermediate peripheral portion is formed in a curved shape or a tapered shape in which the flat bottom portion has a small diameter, and the heating device is attached to a lower surface of the flat bottom portion. Water heater.