JP4239408B2 - Electric water heater - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric water heater provided with a ground wire connection terminal for connecting a ground wire.
[0002]
[Prior art]
In some cases, it is necessary to provide an electric water heater with a ground wire connection terminal for connecting a ground wire according to the standard for electric products. The electric water heater in such a case generally has a structure as shown in FIGS. That is, reference numeral 1 denotes a container for containing water that opens upward, and an electric heater 2 is attached to the bottom of the container 1. Reference numeral 3 denotes a resin outer frame covering the container 1. An opening 4 is provided on the bottom surface of the outer frame 3, and the opening 4 is covered with a back plate 5. Reference numeral 6 denotes a metal heat shield, which is fixed to the container 1. After the outer frame 3 is set on the container 1, a metal grounding metal 7 is attached to the heat shield 6. A ground wire connection terminal 8 having a female screw is fixed to the ground metal fitting 7, and the ground wire connection terminal 8 is inserted from the inside into a through hole 9 provided on the side surface of the outer frame 3. Reference numeral 10 denotes a fixing screw for attaching the ground wire 11 to the ground wire connection terminal 8. When the ground wire 11 is screwed to the ground wire connection terminal 8, the container 1 having the electric heater 2 is grounded via the ground metal fitting 7 and the heat shield plate 6.
[0003]
[Problems to be solved by the invention]
However, in the above-described conventional configuration, the ground metal 7 must be attached to the heat shield plate 6 after the container 1 is set in the outer frame 3, and it is difficult to assemble because the work is performed in a narrow part. If the positions of the outer frames 3 are shifted from each other, the ground wire connection terminal 10 cannot be inserted into the through hole 11 and cannot be assembled.
[0004]
SUMMARY OF THE INVENTION The present invention solves such a conventional problem, and aims to make it easy to assemble and to assemble regardless of the positional deviation between the container and the outer frame.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is to form a ground metal fitting made of a conductive material integrally with a ground wire connection terminal and connected to a container with a conductive lead wire, and hold the ground metal fitting on the bottom surface of the outer frame. It is clamped and held by the part.
[0006]
As a result, the grounding metal can be attached to the outer frame in advance, and assembly is facilitated. In addition, since the ground metal fitting is directly fixed to the outer frame and is detachably connected by the lead wire of the connecting means, it can be assembled regardless of the position of the container.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The invention according to claim 1 of the present invention includes a container for storing water provided with a charging unit, an outer frame that surrounds the container and that has an open bottom surface and is integrally provided with a grounding metal holding unit, and a side surface of the outer frame. A conductive earth metal fitting provided with a through hole provided in the terminal, a grounding wire connecting terminal and a latching part for engaging with the earth metal fitting holding part, and a detachable conductive material for electrically connecting the earth metal fitting. Connecting means, and holding the earth metal fitting between the earth metal fitting holding part of the outer frame and inserting the earth wire connection terminal into the through hole to prevent the earth metal fitting from being attached. It can be made into a frame to facilitate assembly. In addition, since the grounding metal is directly fixed to the outer frame, it can be assembled regardless of the position of the container.
[0008]
According to a second aspect of the present invention, in the configuration of the first aspect, an electrical connection means between the container and the grounding metal is provided via a metal back plate and a container fixing screw for fastening the back plate to the container. As a result, it is possible to connect to the ground simply by screwing without the need for a lead wire, and further facilitate assembly.
[0009]
The invention according to claim 3 of the present invention is the structure of claim 2, wherein the holding part of the grounding metal is provided with a hole, and the back plate electrically connected to the container is fixed together with the grounding metal with a screw. The earth continuity between the grounding metal and the container is more reliable.
[0010]
According to a fourth aspect of the present invention, in the structure according to any one of the first to third aspects, the main body includes a stopper that abuts when the ground wire connection terminal is pushed inward. Even if it is forced into the inside, it will not come out of the insertion hole.
[0011]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0012]
Example 1
FIG. 1 is a diagram showing a lower cross section of an electric water heater according to a first embodiment of the present invention, FIG. 2 is a diagram showing an enlarged cross section of the main part of the electric water heater, and FIG. 3 is a plan view of a grounding fixture and ground wire connection terminal of the electric water heater. FIG. In FIG. 1 to FIG. 3, reference numeral 21 denotes a container for water that opens upward, and a heater 22 is attached to the bottom of the container 21. Reference numeral 23 denotes a resin outer frame covering the container 21, and an opening 24 is provided on the bottom surface 23 a of the outer frame 23, and the opening 24 is covered with a metal back plate 25. Reference numeral 26 denotes a ground wire connection terminal having a female screw. The ground wire connection terminal 26 is inserted into a through hole 27 provided on the side surface of the outer frame 23 from the inside. Reference numeral 28 denotes a ground metal fitting to which the ground wire connection terminal 26 is attached, and a claw 29 is formed in a substantially U-shaped locking portion made of an elastic conductive material. On the bottom surface 23 a of the outer frame 23, a ground metal holding part 23 b that is clamped by the ground metal when the ground wire connection terminal 26 is inserted into the through hole 27 is integrally formed. A recess 30 is provided in the ground metal fitting holding part 23b. A lead wire 31 is connected to a heat shield plate 39 fixed to the container 21, and one end thereof is connected to a tab terminal 32 provided on the ground metal fitting 28. Reference numeral 33 denotes a fixing screw for attaching the ground wire 34 to the ground wire connection terminal 26.
[0013]
Next, the operation of the electric water heater described above will be described. When attaching the grounding metal 28 to the grounding metal holding part 23b of the outer frame 23, the U-shaped opening of the grounding metal 28 is slid on the grounding metal holding part 23b. Then, the grounding metal 28 first expands by the amount of the claw 29 serving as a locking part, and when the claw 29 reaches the recess 30, it returns elastically and the grounding metal 28 cannot be removed. As a result, the earth metal fitting 28 is held by the earth metal fitting holding portion 23b so that the outer frame 23 can be handled with the earth metal fitting 28 fixed. When assembling the container 21 and the outer frame 23, the outer frame 23 to which the ground metal fitting 28 is assembled is put on the container 21, and the lead wire 31 is connected to the tab terminal 32. When the ground wire 34 is connected to the ground wire connection terminal 26, the container 21 is grounded through the ground metal fitting 28, the lead wire 31, and the heat shield plate 39.
[0014]
As described above, the ground metal fitting 28 can be attached in advance to the outer frame 23 before being set in the container 21 and can be easily assembled.
[0015]
In addition, since the grounding metal 28 is directly fixed to the outer frame 23, it can be assembled regardless of the position of the container 21.
[0016]
In the drawings and description, the ground metal fitting 28 is prevented from coming off by engagement of the claw 29 and the concave portion 30 of the ground metal fitting holding portion 23b. However, the method for preventing the ground metal fitting is not limited to this.
[0017]
(Example 2)
FIG. 4 is a view showing a lower section of the electric water heater according to the second embodiment. In FIG. 4, the ground metal fitting 28 is brought into contact with the back plate 25, and the back plate 25 is further fixed to a container support metal fitting 40 attached to the container 21 with a metal container fixing screw 35. The ground wire 34 is electrically connected to the ground via the container fixing screw 35, the back plate 25, the ground metal fitting 28, and the ground wire connection terminal 26. Therefore, the lead wire 31 is not necessary, and the container 21 can be connected to the ground simply by tightening the container fixing screw 35, and the assembly is further facilitated.
[0018]
(Example 3)
FIG. 5 is a view showing a lower section of the electric water heater of the third embodiment. In FIG. 5, a hole 37 is provided in a portion where the back plate fixing screw 36 is tightened on the back plate 25 side of the ground metal fitting 28, and is fixed to the ground metal fitting holding portion 23 b on the bottom surface 23 a of the outer frame 3 together with the back plate 25. The back plate 25 electrically connected to the container 21 and the ground metal fitting 28 come into strong contact with each other, and the earth continuity becomes more reliable. The hole 37 may be a groove.
[0019]
(Example 4)
FIG. 6 is a view showing a lower cross section of the electric water heater of Example 4, and FIG. 7 is a view showing an enlarged cross section of a main part of the electric water heater. 6 and 7, the stopper 38 is attached to the container 21 when the ground wire connection terminal 26 is pushed inward, and the ground metal fitting 28 is attached even if the ground wire connection terminal 26 is forced into the main body. The pushing amount is regulated by hitting the stopper 38, and the ground wire connection terminal 26 is not detached from the through hole 27.
[0020]
In the drawings and description, the stopper 38 is attached to the container 21, but the attachment is not limited to the container 21. Further, the stopper 38 does not have to be a dedicated component that only contacts the grounding metal 28.
[0021]
【The invention's effect】
As is clear from the above embodiment, the grounding metal fitting is sandwiched between the bottoms of the outer frame and is retained so that the grounding metal fitting can be attached in advance to the outer frame before being set in the container, thereby facilitating assembly. In addition, since the grounding metal is directly fixed to the outer frame, it can be assembled regardless of the position of the container.
[Brief description of the drawings]
FIG. 1 is a lower cross-sectional view of an electric water heater showing Embodiment 1 of the present invention. FIG. 2 is an enlarged cross-sectional view of a main part of the electric water heater. FIG. 3 is a plan view of a grounding metal fitting and an earth wire connecting terminal of the electric water heater. 4 is a lower cross-sectional view of an electric water heater showing Example 2 of the present invention. FIG. 5 is a lower cross-sectional view of an electric water heater showing Example 3 of the present invention. FIG. 6 is an electric water heater showing Example 4 of the present invention. Lower cross-sectional view [FIG. 7] An enlarged cross-sectional view of the main part of the electric water heater [FIG. 8] A cross-sectional view of the electric water heater showing a conventional example [FIG. 9] An enlarged cross-sectional view of the main part of the electric water heater [Explanation of symbols]
21 Container 22 Heater (Charging part)
23 Outer frame 23b Ground metal holding part 25 Back plate 26 Ground wire connection terminal 27 Through hole 28 Ground metal 29 Claw (locking part)
31 Lead wire (connecting means)
35 Container fixing screw 36 Back plate fixing screw 37 Hole 38 Stopper

Claims (4)

A container for storing water with a charging unit; an outer frame that surrounds the container and has an open bottom surface; and a grounding metal holding unit integrally provided; a through-hole provided in a side surface of the outer frame; and a ground wire connection terminal A conductive ground metal fitting provided with a locking portion for locking to the ground metal fitting holding portion, and detachable conductive connecting means for electrically connecting the ground metal fitting, An electric water heater that is sandwiched between the ground metal holding part of the outer frame and that holds the ground wire connection terminal in the through hole to prevent it from coming off. The electric water heater according to claim 1, wherein an electrical connection means between the container and the grounding metal is connected to the container with a container fixing screw via a metal back plate. 3. An electric water heater according to claim 2, wherein a hole is provided in the ground metal fitting, and the ground metal fitting electrically connected to the back plate and the container is fastened and fixed to the outer frame with a back plate fixing screw. The electric water heater according to any one of claims 1 to 3, further comprising a stopper in the main body, which abuts when the ground wire connection terminal is pushed inward.

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