JP3376280B2 - 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, and more particularly to an electric water heater such as an electric pot having a vacuum heat insulation space.

[0002]

2. Description of the Related Art In a conventional electric water heater, an annular shoulder member is generally attached to the upper part of an outer casing, an inner container made of metal is engaged with and supported by the shoulder member, and a heater is attached to the bottom of the inner container. In addition, the inner container is fixed to the bottom of the exterior body. A single container is usually used as the inner container, but a vacuum double container is used when particularly high heat retention performance is required.

A conventional electric water heater using a vacuum double container is provided with a through hole at the bottom of a double structure consisting of a bottomed cylindrical inner container and a bottomed cylindrical outer container. An underwater heater is attached to the inner bottom surface, the lead wire of the heater is passed through the through hole, and a water pipe connected to the discharge port is passed through the through hole.

[0004]

However, the electric water heater using the vacuum double container as described above has a structure in which the through hole is provided at the bottom of the inner container having the double structure, and therefore the structure becomes complicated and the cost is reduced. There is a problem of getting high.

Therefore, the present invention utilizes the structure of an electric water heater using a single container which is generally used in the past, and provides an electric water heater having a simple vacuum double structure and high heat retention performance. And

[0006]

In order to solve the above-mentioned problems, the present invention attaches an annular shoulder member to the upper part of an exterior body to engage and support the inner container with the shoulder member, In an electric water heater in which a heater is attached to the bottom of the inner container and the inner container is fixed to the bottom of the exterior body, the inner container is composed of an inner container and an outer peripheral wall member that covers the outer peripheral surface of the inner container through a vacuum heat insulation space. Dividing the outer peripheral wall member into an upper peripheral wall and a lower peripheral wall, forming an outer diameter of the upper peripheral wall to a size that matches an inner diameter La of a vertical wall of the shoulder member, and making an outer diameter of the lower peripheral wall the upper peripheral wall. Radius than outer diameter
It is formed with a small diameter by d and is close to the welding edge of the lower peripheral wall.
The upper and lower parts of the
Place the shoulder member from above against the inner container placed in the opposite direction.
Vertical of the shoulder member when tilted and fitted over the closed portion
The difference La between the inner diameter La of the wall and the inner diameter Lb when it is viewed from above
The size of the dimension d is such that −Lb is equal to 2d.
It has a set configuration.

The outer peripheral wall member may cover the outer peripheral surface of the inner container and the peripheral portion of the bottom surface continuous to the outer peripheral surface via a vacuum heat insulating space.

Further, a structure in which reinforcing ribs are formed in the circumferential direction on the upper peripheral wall, or the lower peripheral wall is subjected to a contraction process with the upper peripheral wall as a reference with the difference in diameter between the upper peripheral wall and the lower peripheral wall. Alternatively, the upper peripheral wall may be expanded by using the lower peripheral wall as a reference.

Further, the peripheral portion of the exhaust port is located on one plane, and the projecting height of the peripheral portion of the exhaust port from the lower peripheral wall is set within a range not exceeding the outer diameter of the upper peripheral wall. Alternatively, the closed portion of the exhaust port may be a chip tube closed by pressure bonding or a welded closed lid.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. In the electric water heater of the embodiment shown in FIG. 1, an annular shoulder member 2 is attached to the upper end of an outer casing 1. Vertical wall 3 provided at the lower end of the shoulder member 2
The inner container support portion 5 is formed by the horizontal step portion 4 provided outward at the upper end of the vertical wall 3.

An inner container 6 is housed inside the outer casing 1, and an outward flange 7 formed on the upper end of the inner container 6 is engaged and supported by the inner container supporting portion 5. A lid set 8 is openably and closably attached to the rear end of the shoulder member 2 by a hinge pin 9, a packing 12 is attached to an outer peripheral edge of an inner lid 11 attached to a lower surface of the lid set 8, and the packing 12 is contained. The inner container 6 is closed by contacting the seal portion 18 on the inner peripheral surface of the upper end portion of the container 6.

As shown in FIG. 2, the inner container 6 is an inner container 13 made of a single type metal container used in a normal electric water heater, and an outer peripheral wall for covering the outer peripheral surface thereof with a required gap. And the member 14.

A heater 15 is mounted on the bottom of the inner container 13, and a temperature sensor mounting portion 16 is provided at the center of the bottom of the bottom surrounded by the heater 15. Further, around the heater 15, a connection port 17 of the water passage 20 is provided in a part of the bottom surface portion. Further, the above-described seal portion 18 that is drawn inward is formed on the upper portion of the inner peripheral surface of the inner container 13, and an outward flange portion 19 is formed on the upper end of the inner container 13.

The heater 15 is spot-welded to the inner bottom surface of the inner container 13 after the inner container 13 is molded or after the outer wall member 14 is attached to the inner container 13 to form a double structure. In this case, the welding jig is the above-mentioned seal portion 18
In order not to interfere with the inner peripheral surface of the
It is desirable to set the inner diameter L ₁ (see FIG. 3) of the heater to be larger than the maximum diameter L ₂ of the spot welded portion of the heater 15.

The outer peripheral wall member 14 is a metal cylindrical member that covers the outer peripheral surface of the inner container 13 with a required gap, and as shown in FIG. 2, the upper peripheral wall 21 of the upper half portion.
And the lower peripheral wall 22 in the lower half portion.

The upper peripheral wall 21 is formed to have an outer diameter that matches the inner diameter of the vertical wall 3 that constitutes the inner container supporting portion 5 of the shoulder member 2, and the outer diameter of the lower peripheral wall 22 is a radius d from this. Only small diameter is formed.

As described above, the upper peripheral wall 21 and the lower peripheral wall 2
As a method of making the two diameters different, there are a method of reducing the diameter of the lower peripheral wall 22 side with respect to the upper peripheral wall 21 and a method of expanding the upper peripheral wall 21 with the lower peripheral wall 22 as a reference.

In the former case, the upper peripheral wall 2 has the same rigidity as that of the lower peripheral wall 22 whose rigidity increases due to work hardening by the diameter reduction processing.
In order to impart the number 1 to the upper peripheral wall 21, a plurality of circumferentially inward reinforcing ribs 23 are formed on the upper peripheral wall 21.

An outward flange 24 is provided on the upper end of the upper peripheral wall 21, a welding edge 25 is provided on the lower end of the lower peripheral wall 22, and a portion of the lower peripheral wall 22 near the welding edge 25 is further provided. An exhaust port 26 for vacuum exhaust is provided.

The height h of the peripheral portion 26 'of the exhaust port 26 (see FIG.
(A) to (c)) is set to be equal to or less than the above-mentioned dimension d. That is, the peripheral portion 26 ′ of the exhaust port 26 has the upper peripheral wall 21.
The height is set so as not to project from the outer peripheral surface of the. This is to prevent the peripheral edge portion 26 ′ of the exhaust port 26 from coming into contact with the insertion port of the welding machine when the outer peripheral wall member 14 is fitted into the inner container 13 and inserted into the welding machine. Further, in order to avoid interference with the welding machine, as shown in FIGS. 5A to 5C, it is desirable that the opening surface 32 of the peripheral edge portion 26 ′ be formed so as to be on one plane.

In addition, at the lower end of the lower peripheral wall 22, as shown in FIG.
As shown in (b), an extension portion 27 extending downward from the inner container 13 may be provided, and a welding edge 25 may be provided at an inwardly folded back portion of the extension portion 27.

When the evacuation method is the tip tube method, the tip tube 28 (see FIG. 2) is welded to the exhaust port 26.

The outer peripheral wall member 14 is the inner container 1 described above.
3 is fitted on the outer side of the collar 3, and the collar 24 is overlapped with the lower surface of the collar 19 of the inner container 13 and welded to form the collar 7. Further, the welding edge 25 is welded to the outer peripheral surface of the inner container 13. When there is an extension 27 (Fig. 4
In (b), the welding edge 25 is welded to the peripheral portion of the bottom surface of the inner container 13. The extension portion 27 is continuous with the outer peripheral surface of the inner container 6 and covers the peripheral portion of the bottom surface.

After that, evacuation is performed and the inner container 13
A vacuum heat insulating space 29 is formed between the outer peripheral wall member 14 and the outer peripheral wall member 14. When the evacuation is completed, in the case of the tip tube system, the tip portion of the tip tube 28 is cut and removed, and the tip portion of the residual tip tube 30 is pressure-bonded to form the blocking portion 31. In the case of vacuum evacuation by the vacuum furnace method, the closing lid 33 (see FIG. 4C) is welded to the exhaust port 26 provided in the lower peripheral wall 22 by brazing or the like.

In the above vacuum insulation space 29, a copper foil 35 is intervened in advance to enhance the heat insulation effect, and a getter 36 wrapped in the copper foil 35 by the method described later is intervened in the seal portion 18. .

FIG. 6 shows an inner container 6 of another embodiment. In this case, the outer diameter of the outer peripheral wall member 14 is formed to be the outer diameter of the lower peripheral wall 22, and the upper peripheral wall 21 is bulged outward. The rib 34 is provided, and the height of the reinforcing rib 34 is set to the above-mentioned dimension d.
Is set to produce a dimensional difference d from the outer diameter of the lower peripheral wall 22. The uppermost one of the reinforcing ribs 34 is formed at a position where it can be inscribed in the vertical wall 3 (see FIG. 2) of the shoulder member 2 when assembled with the shoulder member 2.
Other configurations are the same as those in the above case.

Next, the procedure for combining the inner container 6 and the shoulder member 2 will be described with reference to FIG. When combining the two, the shoulder member 2 is tilted with respect to the inner container 6 placed upside down, and the shoulder chip 2 is fitted over the closing portion 31 (the closing lid 33 in the case of the vacuum furnace system) of the residual chip tube 30, and then the The inner container 6 is positioned in the radial direction with respect to the shoulder member 2 by returning to the horizontal state (see the chain double-dashed line) and fitting the vertical wall 3 of the inner container support portion 5 to the upper peripheral wall 21. Further, the flange 7 is applied to the horizontal step portion 4 to perform vertical positioning, and the inner container 6 is engaged with and supported by the shoulder member 2.

When the shoulder member 2 and the inner container 6 are assembled as described above, the closing portion 31 of the residual tip tube 30 and the closing lid 3 are formed.
Since it is necessary to go over the portion 3, it is necessary to incline the shoulder member 2. Due to the inclination, the inner diameter La of the vertical wall 3 of the shoulder member 2 (this is substantially the same as the outer diameter of the upper peripheral wall 21 of the inner container 6) is as shown by the chain double-dashed line in FIG. The inner diameter seen from the upper surface is reduced to Lb. This inner diameter Lb
And the inner diameter of the lower peripheral wall 22 are substantially equal to each other, or slightly Lb
Is set to be larger. The above difference in inner diameter L
The size of the dimension d is set so that a-Lb is equal to or slightly larger than 2d.

Incidentally, in order to set the dimension d as small as possible, the closing portion 31 of the remaining tip tube 30 and the closing lid 33.
It is desirable to make the height of protrusion from the lower peripheral wall 22 or the height from the bottom surface of the inner container 6 as small as possible.

After the assembly of the shoulder member 2 and the inner container 6 is completed, the exterior body 1 and the lid set 8 are assembled.

The electric water heater assembled as described above is used in the same manner as an ordinary electric pot, but in this case, most of the outer peripheral surface of the inner container 6 or the outer peripheral surface and the peripheral portion of the bottom surface. (In the case of FIG. 4B), it is thermally insulated by the vacuum heat insulating space 29.

8 and 9 show a method of mounting the getter 36 described above. In the method shown in FIGS. 8A to 8D, both ends 37 of the copper foil 35 wound around the outer peripheral surface of the inner container 13 are aligned and erected outward, and at the position corresponding to the seal portion 18, The getter 36 is wrapped inside the both end portions 37 (Fig. (D)), and further bent inward to seal the seal portion 1.
It is located in the recess of 8.

In the method shown in FIG. 9, both ends 3 of the copper foil 35 are
The getter 36 is wound around the corner of one end 37 of the seal 7, and the getter 36 is positioned in the recess of the seal portion 18 without overlapping with the other end 37.

[0034]

As described above, according to the present invention, as the basic structure, the structure of the electric kettle of a conventional general single-layer inner container can be used. With a simple structure of forming a vacuum heat insulation space, an electric water heater with high heat retention performance can be realized.

Further, by adopting a structure in which the outer diameter of the lower peripheral wall is smaller than that of the upper peripheral wall of the outer peripheral wall member, even if the closed portion for vacuum evacuation remains on the lower peripheral wall, it interferes with it. The shoulder member and the inner container can be combined without causing any trouble, and the assembly work is not hindered.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment.

FIG. 2 is a partially enlarged sectional view of the above.

FIG. 3 is a cross-sectional view of the inner container of the above.

4A to 4C are partial cross-sectional views of a modified example of the above inner container.

FIG. 5 (a) is a front view of the exhaust port portion of the inner container of the above. (B) Sectional drawing of the bb line of (a) figure (C) Sectional drawing of the cc line of (b) figure

FIG. 6 is a partial cross-sectional view of another modification of the above inner container.

FIG. 7A is a sectional view of the same combination state as above. (B) Diagram of the relationship between the shoulder member and the inner container shown in (a)

8A to 8D are perspective views showing a procedure of a getter mounting method.

9A to 9C are perspective views showing a procedure of another method of mounting a getter on a substrate.

[Explanation of symbols]

1 exterior body 2 shoulder members 3 vertical walls 4 horizontal steps 5 Inner container support 6 inner container 7 brim 8 lid set 9 Hinge pin 11 Inner lid 12 packing 13 Inner container 14 Outer wall member 15 heater 16 Temperature sensor mounting part 17 connection 18 Seal part 19 brim 20 waterways 21 Upper peripheral wall 22 Lower wall 23, 23 'Reinforcing ribs 24 brim 25 Weld edge 26 Exhaust port 26 'periphery 27 Extension 28 tip tubes 29 Vacuum insulation space 30 Remaining tip tube 31 Block 32 open surface 33 Closure lid 34 Reinforcing rib 35 copper foil 36 getter 37 Edge

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Ito 1-20-5 Tenma, Kita-ku, Osaka City, Zojirushi Mahobin Co., Ltd. (56) Reference JP-A-7-275135 (JP, A) JP-A 4-164412 (JP, A) JP 63-135111 (JP, A) Actual development 61-35624 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) A47J 27/21 101

Claims (7)

(57) [Claims] 1. An annular shoulder member is attached to the upper part of the exterior body,
In an electric water heater in which the inner container is engaged and supported by the shoulder member, a heater is attached to the bottom of the inner container, and the inner container is fixed to the bottom of the outer casing, the inner container is the inner container and its outer periphery. The surface is constituted by an outer peripheral wall member that covers a vacuum insulation space, the outer peripheral wall member is divided into an upper peripheral wall and a lower peripheral wall, and the outer diameter of the upper peripheral wall is matched with the inner diameter La of the vertical wall of the shoulder member. The outer diameter of the lower peripheral wall is larger than the outer diameter of the upper peripheral wall by a dimension d.
A part of the lower peripheral wall that is formed to have a small diameter and is close to the welding edge.
Min provided the occlusion of the exhaust port for evacuation in the vertical GyakuMuko
Inclining the shoulder member with respect to the inner container
Inner diameter La of the vertical wall of the shoulder member when fitted over the closing portion
And the difference La−Lb of the inner diameter Lb when viewed from the top is 2d
An electric water heater characterized in that the size d is set so as to be equal to . 2. The electric water heater according to claim 1, wherein the outer peripheral wall member covers an outer peripheral surface of the inner container and a peripheral portion of a bottom surface continuous with the outer peripheral surface via a vacuum heat insulation space. . 3. The electric water heater according to claim 1, wherein reinforcing ribs are formed in a circumferential direction on the upper peripheral wall. 4. The difference in diameter between the upper peripheral wall and the lower peripheral wall,
3. The pipe is formed by contracting the lower peripheral wall with the upper peripheral wall as a reference, or by expanding the upper peripheral wall with the lower peripheral wall as a reference. An electric water heater according to any one of 1. 5. The electric water heater according to claim 1, wherein a peripheral portion of the exhaust port is on one plane. 6. The electricity according to claim 1, wherein a projection height of the peripheral portion of the exhaust port from the lower peripheral wall is set within a range not exceeding the outer diameter of the upper peripheral wall. Water heater. 7. The electric water heater according to claim 1, wherein the closed portion of the exhaust port is a chip tube closed by crimping or a closed lid welded.