water heater

Abstract

To provide a water heater having a high degree of freedom in designing the inside of a housing, while reducing costs with a small number of components.SOLUTION: A guide rib 31 extending in a longitudinal direction is disposed on a front end portion of a lower plate 9A of an electrical box 9 in a manner of projecting downward, a slit 21 opened at a front end edge of a bottom plate 20 and extending backward from the front end edge is formed on the bottom plate 20, and an electrical box 9 is attached and removed by moving a rib main body 32 of the guide rib 31 to the inside and outside of the slit 21 in accompany with sliding in the longitudinal direction of the electrical box 9. Thus, the need for installing a pedestal applied in a conventional water heater is eliminated, so that costs can be reduced with a small number of components, and further a degree of freedom in designing the inside of the housing can be improved in a water heater 1.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to a water heater in which an electrical equipment box for accommodating a controller is installed at the bottom of a housing.

Background Art

[0002] In a conventional water heater, an electrical equipment box for accommodating a controller is installed at the bottom of a housing. And, in order to smoothly insert and remove such an electrical equipment box with respect to the housing, while providing a protruding portion that protrudes downward on the lower surface of the electrical equipment box, a receiving base having a slit extending along the insertion / removal direction of the electrical equipment box is provided on the bottom plate of the housing, and a water heater has been devised in which the protruding portion is guided by the slit when the electrical equipment box is inserted and removed (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the water heater described in Patent Document 1, since it is necessary to install the above-described receiving base on the bottom plate of the housing, the number of parts is large and the cost is high. In addition, the space inside the housing is restricted by the receiving base, and the design freedom inside the housing is low.

[0005] Therefore, the present invention has been made in view of the above problems, and aims to provide a water heater that has a small number of parts, can reduce costs, and has a high degree of design freedom inside the housing.

Means for Solving the Problems

[0006] To achieve the above objective, the invention described in claim 1 of the present invention is a water heater in which an electrical box housing a controller is installed on the bottom plate of the housing so as to be removable by sliding it in a predetermined direction, wherein a rib extending in a predetermined direction is provided projecting downward from the lower plate of the electrical box, and a slit is provided in the bottom plate that opens at the edge of the bottom plate and extends from the edge in a predetermined direction, and as the electrical box slides in the predetermined direction, the rib moves in and out of the slit to attach and detach the electrical box, while the rib or the lower plate of the electrical box is provided with a closing part that is wider than the slit and contacts the bottom plate when the electrical box is installed to close the slit. The invention described in claim 2 is characterized in that, in the invention described in claim 1, a restricting portion is provided at the lower end of the rib, which is wider than the slit and prevents the rib from slipping upward from the slit. The invention described in claim 3 is characterized in that, in the invention described in claim 1 or 2, the lower plate of the electrical box is provided with a support projection that protrudes downward and abuts against the bottom plate, while the bottom plate is provided with a bulge that bulges upward, and as the electrical box slides in a predetermined direction, the support projection moves over the bulge. [Effects of the Invention]

[0007] According to the present invention, a rib extending in a predetermined direction is provided projecting downward from the lower plate of the electrical box, while a slit is provided in the bottom plate, opening at the edge of the bottom plate and extending from the edge in a predetermined direction. As the electrical box slides in the predetermined direction, the rib moves in and out of the slit, allowing the electrical box to be attached and detached. Therefore, since there is no need to install a support stand as used in conventional water heaters, the number of parts is reduced, costs can be lowered, and the water heater can be made with a high degree of design freedom within the housing. Furthermore, the ribs or the lower plate of the electrical box are provided with a closing section that is wider than the slit and contacts the bottom plate when the electrical box is installed to close the slit. Therefore, even though slits are provided in the bottom plate, the combustion performance of the water heater is not affected. Furthermore, according to the invention described in claim 2, a restricting portion is provided at the lower end of the rib that is wider than the slit and prevents the rib from slipping upward through the slit, thereby reliably preventing the electrical box from unintentionally shifting from its installation position while it is in place. In addition, according to the invention described in claim 3, the lower plate of the electrical box is provided with a support projection that protrudes downward and abuts against the bottom plate, while the bottom plate is provided with a bulge that bulges upward, so that as the electrical box slides in a predetermined direction, the support projection moves over the bulge. Therefore, it is less likely that the electrical box will not be pushed in far enough in the sliding direction to reach the installation position, and it is extremely reliable to prevent the electrical box from unintentionally shifting from its installation position while it is in place. [Brief explanation of the drawing]

[0008] [Figure 1] This is an explanatory diagram showing a water heater from the front with its front cover removed. [Figure 2] This is an explanatory diagram showing an enlarged view of region A in Figure 1. [Figure 3] This is a perspective view diagram showing the electrical box installed on the bottom plate of the enclosure, as seen from above. [Figure 4] This is a perspective view diagram showing the electrical box installed on the bottom plate of the enclosure, viewed from below. [Figure 5] This is an explanatory diagram showing the electrical box from the front. [Figure 6] This is a perspective view diagram showing the electrical box from below. [Figure 7] This is an explanatory diagram showing the base plate from above. [Figure 8] This is a perspective view diagram showing the base plate from the front. [Figure 9] This is an explanatory diagram showing a vertical cross-section of the enclosure with the front cover attached, where the electrical box is installed. [Figure 10] This is an explanatory diagram showing an enlarged view of region B in Figure 9. [Modes for carrying out the invention]

[0009] The following describes in detail, based on the drawings, a water heater that is one embodiment of the present invention. Figure 1 is an explanatory diagram showing the water heater 1 from the front with the front cover removed. Figure 2 is an explanatory diagram showing an enlarged view of area A in Figure 1. Figure 3 is an explanatory perspective view from above showing the electrical box 9 installed on the bottom plate 20 of the housing 2. Figure 4 is an explanatory perspective view from below showing the electrical box 9 installed on the bottom plate 20 of the housing 2. Figure 5 is an explanatory diagram showing the electrical box 9 from the front. Figure 6 is an explanatory perspective view showing the electrical box 9 from below. Figure 7 is an explanatory diagram showing the bottom plate 20 from above. Figure 8 is an explanatory perspective view showing the bottom plate 20 from the front. Figure 9 is an explanatory diagram showing a vertical cross-section of the electrical box 9 installed inside the housing 2 with the front cover 40 attached. Figure 10 is an explanatory diagram showing an enlarged view of area B in Figure 9.

[0010] The water heater 1 consists of a combustion device 3, a heat exchanger 4, and an exhaust unit 5, all housed in a rectangular box-shaped enclosure 2. The combustion device 3 includes an inner case 6 that houses a burner unit (not shown). The burner unit consists of multiple dilution burners, which are flattened in the left-right direction, arranged in a left-right direction. A gas distribution unit 7 is assembled on the front of the inner case 6 for distributing and supplying fuel gas to each group of burners with different numbers of dilution burners.

[0011] An air supply fan 8 that supplies combustion air to the combustion device 3 is mounted on the lower left side of the combustion device 3. Below the combustion device 3, on the right side inside the housing 2, an electrical box 9 housing a controller that controls the operation of the water heater 1 is detachably installed on the housing 2. The electrical box 9 is formed in a rectangular box shape and is installed in an upright position in which the left-right direction is shorter than the front-to-back and up-to-down directions. On the other hand, the exhaust section 5 has horizontally elongated exhaust pipes 10 that protrude forward through the front cover 40.

[0012] The heat exchanger 4 is of a fin-tube type having heat transfer tubes that meander through a plurality of fins arranged in parallel in the thickness direction. A water supply pipe 11 is connected to the inlet end of the heat transfer tube, and a hot water outlet pipe 12 is connected to the outlet end of the heat transfer tube. On the lower surface of the housing 2, a water inlet 13 to which an external water pipe is connected and a hot water outlet 14 to which an external pipe to a hot water tap is connected are provided. The upstream end of the water supply pipe 11 is connected to the water inlet 13, and the downstream end of the hot water outlet pipe 12 is connected to the hot water outlet 14. Further, on the lower surface of the housing 2, a gas inlet 15 to which an external gas pipe is connected is provided. The gas inlet 15 is connected to the gas distribution unit 7 in the housing 2 via a gas proportional valve unit 16 having a proportional valve 17 and a primary solenoid valve 18 on the upstream side thereof.

[0013] Here, the installation structure of the electrical box 9, which is a main part of the present invention, will be described. As an installation structure on the side of the electrical box 9, the electrical box 9 is provided with a guide rib 31 and a support protrusion 35. The guide rib 31 protrudes downward from the front end portion of the lower plate 9A of the electrical box 9 and includes a rib body 32 extending in the front-rear direction, a lower overhang portion 33 protruding in the left-right direction from the tip (lower end) of the rib body 32, and an upper overhang portion 34 protruding in the left-right direction at a position between the lower overhang portion 33 and the base end of the rib body 32 in the vertical direction. On the other hand, the support protrusion 35 protrudes downward from the rear end portion of the lower plate 9A of the electrical box 9. The amount of protrusion of the support protrusion 35 from the lower plate 9A is substantially the same as the amount of protrusion from the base end of the guide rib 31 to the lower surface of the upper overhang portion 34.

[0014] On the other hand, the housing 2 has an installation structure, and the bottom plate 20 is provided with a slit 21, an entrance / exit 23, and a bulging portion 25. The slit 21 opens at the front edge of the bottom plate 20 and extends linearly from the front edge to the rear. The width of the slit 21 is wider than the width of the rib body 32, and narrower than the width of the lower protrusion 33 and the upper protrusion 34. However, the front part of the slit 21 has a tapered portion 22 that gradually widens towards the front, and the width of the front end of the slit 21 is slightly wider than the width of the lower protrusion 33. In addition, the front end of the bottom plate 20 is provided with a bent portion 20A that is bent downward, and the bent portion 20A is provided with an entrance / exit 23 that is cut out downward from the front end of the slit 21. The guide rib 31, including the lower protrusion 33, can be moved in and out of the slit 21 through this entrance / exit 23. Furthermore, at the rear of the base plate 20, a bulging portion 25 is provided in a location that will be in front of the support projection 35 when the electrical box 9 is installed, and which bulges upward.

[0015] To install the electrical box 9 on the base plate 20, the electrical box 9 is slid backward with the support projection 35 positioned on the base plate 20, allowing the guide rib 31 to enter the slit 21 from the entrance 23, particularly the portion of the rib body 32 between the lower protrusion 33 and the upper protrusion 34 to enter the slit 21. Then, the electrical box 9 is slid backward until the support projection 35 has overcome the bulging portion 25, completing the installation of the electrical box 9. To remove the electrical box 9, the electrical box 9 is slid forward, and the guide rib 31 is pulled out of the slit 21.

[0016] Also, in the state where the electrical component box 9 is installed, the lower end of the support protrusion 35 and the lower surface of the upward protruding portion 34 are in contact with the upper surface of the bottom plate 20, and the slit 21 is blocked by the upward protruding portion 34. Further, when the front cover 40 is attached so as to close the front surface of the housing 2, the packing 41 attached to the lower end of the inner surface of the front cover 40 abuts on the front surface of the bent portion 20A of the bottom plate 20 and the front surface of the guide rib 31, and the entrance / exit 23 is blocked by the packing 41. That is, although the slit 21 and the entrance / exit 23 are provided in the bottom plate 20, both are blocked so as not to affect the combustion performance of the water heater 1. In addition, even if an attempt is made to move the installed electrical component box 9 upward, the downward protruding portion 33 functions as a retaining means to prevent the upward movement of the electrical component box 9, that is, the upward removal of the guide rib 31 from the slit 21.

[0017] According to the water heater 1 having the above-described configuration, a guide rib 31 extending in the front-rear direction is provided so as to project downward at the front end portion of the lower plate 9A of the electrical component box 9. On the other hand, a slit 21 that opens at the front edge of the bottom plate 20 and extends rearward from the front edge is provided in the bottom plate 20. As the electrical component box 9 slides in the front-rear direction, the rib body 32 of the guide rib 31 moves inside and outside the slit 21 so that the electrical component box 9 can be attached and detached. Therefore, since there is no need to install a pedestal employed in conventional water heaters, the number of parts can be reduced and the cost can be reduced, and the water heater 1 can be provided with a high degree of design freedom inside the housing.

[0018] Further, the guide rib 31 is provided with an upward protruding portion 34 that is wider in the left-right direction than the slit 21 and abuts on the upper surface of the bottom plate 20 when the electrical component box 9 is installed to block the slit 21. At the lower end of the inner surface of the front cover 40, a packing 41 is provided that abuts on the bent portion 20A to block the entrance / exit 23 when attached to the housing 2. Therefore, although the slit 21 and the entrance / exit 23 are provided in the bottom plate 20, both are blocked so as not to affect the combustion performance of the water heater 1.

[0019] Furthermore, a downward protrusion 33 is provided at the lower end of the guide rib 31, which is wider than the slit 21 and prevents the guide rib 31 from slipping upward from the slit 21. This ensures that the electrical box 9, while installed, does not unintentionally shift from its installation position. In addition, the lower plate 9A of the electrical box 9 is provided with a support projection 35 that protrudes downward, while the bottom plate 20 is provided with a bulge 25 that bulges upward. When the electrical box 9 is slid in the front-to-back direction for installation, the support projection 35 is configured to move over the bulge 25. Therefore, it is unlikely that the electrical box 9 will not be pushed far enough backward to its installation position, and it is extremely reliable to prevent the electrical box 9 from unintentionally shifting from its installation position while it is in place.

[0020] Furthermore, the water heater according to the present invention is not limited in any way to the embodiments described above, and the overall configuration of the water heater, as well as the configuration related to the installation of the electrical box, can be modified as needed.

[0021] In the above embodiment, the electrical box is configured to be installed by sliding it in the front-to-back direction relative to the bottom plate of the housing. However, it may also be configured to be installed by sliding it in a direction other than the front-to-back direction. For example, if it is configured to be installed by sliding it in the left-to-right direction, ribs or slits extending in the left-to-right direction can be provided. Furthermore, in the above embodiment, the rib is provided with an upper protrusion as a closing section and a lower protrusion as a restricting section, but there is no problem if only one of them is provided, or if neither is provided. In addition, regarding the closing section, instead of providing it on the rib, it is also possible to provide a separate protrusion on the lower plate of the electrical box, or to give the lower plate of the electrical box the function of a closing section, and configure the lower plate of the electrical box to abut against the bottom plate to close the slit. Furthermore, although the above embodiment employs a configuration in which a bent portion is provided in the bottom plate and an opening is provided in the bent portion, there is no problem in any way if a bent portion is not provided in the bottom plate, or if a slit is provided in a place where a bent portion is not provided. [Explanation of Symbols]

[0022] 1. Water heater, 2. Housing, 9. Electrical box, 9A. Bottom plate, 20. Base plate, 20A. Bent section, 21. Slit, 22. Tapered section, 23. Inlet / outlet, 25. Bulging section, 31. Guide rib (rib), 32. Rib body, 33. Lower overhang (regulating section), 34. Upper overhang (closing section), 35. Support projection, 40. Front cover, 41. Packing.

Claims

1. A water heater in which an electrical box housing a controller is detachably installed on the bottom plate of the enclosure by sliding it in a predetermined direction, The lower plate of the electrical box has a rib that protrudes downward in the predetermined direction, and the bottom plate has a slit that opens at the edge of the bottom plate and extends from the edge in the predetermined direction. As the electrical box slides in the predetermined direction, the ribs move in and out of the slit, allowing the electrical box to be attached and detached. A water heater characterized in that the rib or the lower plate of the electrical box is provided with a closing portion that is wider than the slit and contacts the bottom plate when the electrical box is installed to close the slit.

2. The water heater according to claim 1, characterized in that a restricting portion wider than the slit is provided at the lower end of the rib to prevent the rib from slipping upward from the slit.

3. The lower plate of the electrical box is provided with a support projection that protrudes downward and abuts against the bottom plate, The bottom plate is provided with a bulging portion that protrudes upward, The water heater according to claim 1 or 2, characterized in that the support projection overcomes the bulging portion as the electrical box slides in the predetermined direction.

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