Water heater

Abstract

A water heater according to an aspect of the present disclosure comprises: a housing; a heating part which is housed inside the housing; an expansion tank which is housed inside the housing; a circulation path part which passes through the heating part; a branch path part which branches off from the circulation path part and is connected to the expansion tank; and a tank support part that supports the expansion tank in the housing. The tank support part has a first support positioned on a first side in a first direction orthogonal to the vertical direction relative to the expansion tank, and a second support positioned on a second side in the first direction relative to the expansion tank. The first support has a first support surface for supporting the expansion tank from the lower side. The second support has a second support surface for supporting the expansion tank from the upper side.

Description

water heater

[0001] The present disclosure relates to a water heater.

[0002] In order to prevent the pressure in the circulation path from becoming too high, the water heater is provided with an expansion tank that releases the expanded liquid (see, for example, Patent Document 1). The expansion tank is disposed at the upper end of the interior of the water heater.

[0003] Japanese Patent Application Laid-Open No. 2012-220075

[0004] Conventional expansion tanks are supported from below by a support member installed inside the housing, which can vibrate in sympathy with the vibrations of other components such as the pump, causing potential noise. Furthermore, when the expansion tank is firmly fixed to the housing to suppress vibration, the assembly process for the water heater becomes complicated.

[0005] In view of the above circumstances, one of the objects of the present disclosure is to provide a water heater that can suppress rattle of the expansion tank without complicating the assembly process.

[0006] One aspect of a water heater according to the present disclosure comprises a housing, a heating unit housed within the housing, an expansion tank housed within the housing, a circulation path section passing through the heating unit, a branch path section branching from the circulation path section and connecting to the expansion tank, and a tank support section supporting the expansion tank within the housing, wherein the tank support section has a first support section located on a first side of the expansion tank in a first direction perpendicular to the vertical direction, and a second support section located on a second side of the expansion tank in the first direction, wherein the first support section has a first support surface that supports the expansion tank from below, and the second support section has a second support surface that supports the expansion tank from above.

[0007] According to the present disclosure, a water heater can be provided that can suppress rattle of the expansion tank without complicating the assembly process.

[0008] 4 is a diagram showing a schematic view of a water heater according to an embodiment; FIG. 5 is a perspective view of a water heater main body according to an embodiment; FIG. 6 is a front view of a water heater main body according to an embodiment; FIG. 7 is a perspective view of a water heater main body according to an embodiment, showing a state in which a part of the housing is removed; FIG. 8 is an enlarged view of region V in FIG. 4; FIG. 9 is an exploded perspective view of a first support part according to an embodiment; FIG. 10 is a perspective view of a water heater main body around a second support part according to an embodiment, showing a part of the water heater main body broken away.

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the scope of the present disclosure is not limited to the following embodiments and can be modified as desired within the scope of the technical concept of the present disclosure. In addition, in the following drawings, the scale and number of each structure may differ from the scale and number of the actual structure in order to make each configuration easier to understand.

[0010] The drawings also show the X-axis, Y-axis, and Z-axis as appropriate. The X-axis indicates one of the horizontal directions. The Y-axis indicates the other of the horizontal directions. The Z-axis indicates the vertical direction. In the following description, the horizontal direction along the X-axis is referred to as the "front-rear direction X," the horizontal direction along the Y-axis is referred to as the "left-right direction Y," and the vertical direction along the Z-axis is referred to as the "vertical direction Z." The front-rear direction X, left-right direction Y, and vertical direction Z are perpendicular to each other. In the following description, the side of the vertical direction Z toward which the Z-axis arrow points (+Z side) is referred to as the upper side, and the side of the vertical direction Z opposite to the side toward which the Z-axis arrow points (-Z side) is referred to as the lower side. Furthermore, the side of the front-rear direction X toward which the X-axis arrow points (+X side) is referred to as the front side, and the side of the front-rear direction X opposite to the side toward which the X-axis arrow points (-X side) is referred to as the rear side. The left-right direction Y is the left-right direction when the water heater main body 10 in the following embodiments is viewed from the front side (+X side). In other words, the side toward which the Y-axis arrow points in the left-right direction Y (+Y side) is the right side, and the side opposite to the side toward which the Y-axis arrow points in the left-right direction Y (-Y side) is the left side. In the following embodiments, the front-rear direction X corresponds to the "first direction," the rear side corresponds to the "first side" of the first direction, and the front side corresponds to the "second side" of the first direction. In the following embodiments, the left-right direction Y corresponds to the "second direction."

[0011] FIG. 1 is a schematic diagram illustrating a water heater 100 according to the present embodiment. The water heater 100 according to the present embodiment shown in FIG. 1 is a heat pump water heater. As shown in FIG. 1, the water heater 100 includes a water heater main body 10 and an outdoor unit 20. The water heater main body 10 and the outdoor unit 20 are connected to each other by a second circulation path portion 12B through which a refrigerant R flows. Examples of the refrigerant R include a fluorine-based refrigerant or a hydrocarbon-based refrigerant with a low global warming potential (GWP). Examples of the refrigerant R include a single refrigerant selected from R1234yf, R1234ze, R32, and R290, a mixed refrigerant of two or more of these, or a mixed refrigerant of any of these with another refrigerant. Examples of the refrigerant R include a mixed refrigerant containing R1132(E) or a mixed refrigerant containing R1123. Examples of refrigerant R include mixed refrigerants of R516A, R445A, R444A, R454C, R444B, R454A, R455A, R457A, R459B, R452B, R454B, R447B, R447A, R446A, and R459A.

[0012] The water heater main body 10 includes a housing 11, a first circulation path section (circulation path section) 12A, a second circulation path section 12B, a branch path section 17, a heat exchanger 31, a heating section 13, a pump 15, a drain cock 16, a first pressure relief valve 18a, a second pressure relief valve 18b, a gas vent valve 19, a control section 70, and an expansion tank 50. The housing 11 accommodates the first circulation path section 12A, the heat exchanger 31, the heating section 13, the pump 15, the drain cock 16, the second pressure relief valve 18b, the gas vent valve 19, the control section 70, and the expansion tank 50.

[0013] A liquid W1 used for heating and cooling circulates through the first circulation path portion 12A. A heat exchanger 31, a drain cock 16, a pump 15, and a heating unit 13 are arranged in the first circulation path portion 12A. The liquid W1 flowing through the first circulation path portion 12A is, for example, water. The liquid W1 is drained by opening the drain cock 16. The liquid W1 circulates within the first circulation path portion 12A by driving the pump 15.

[0014] An outlet pipe 12c and an inlet pipe 12d are connected to the first circulation path section 12A. The outlet pipe 12c is a pipe for discharging the liquid W1 flowing through the first circulation path section 12A toward an air conditioner and a heat exchanger (not shown). The inlet pipe 12d is a pipe for discharging the liquid W1 from the air conditioner and the heat exchanger into the first circulation path section 12A.

[0015] The refrigerant R circulates through the second circulation path portion 12B. A heat exchanger 31 and the outdoor unit 20 are disposed in the second circulation path portion 12B. The outdoor unit 20 has a heat exchanger that exchanges heat with outside air, and a compressor that circulates the refrigerant R through the second circulation path portion 12B.

[0016] The heat exchanger 31 is a heat exchanger that exchanges heat between the liquid W1 flowing in the first circulation path portion 12A and the refrigerant R flowing in the second circulation path portion 12B. The heat exchanger 31 functions as a heating portion that heats the liquid W1 when transferring heat from the second circulation path portion 12B to the first circulation path portion 12A.

[0017] The heating unit 13 is provided in the first circulation path portion 12A and heats the liquid W1 flowing through the first circulation path portion 12A. The heating unit 13 in this embodiment is a heater. The heating of the liquid W1 by the heating unit 13 is performed by supplying power to the heating unit 13.

[0018] The branch path portion 17 branches off from the first circulation path portion 12A. The branch path portion 17 further branches off into a first branch path 17a, a second branch path 17b, a third branch path 17c, and a fourth branch path 17d. The terminal end of the first branch path 17a is connected to the expansion tank 50. The terminal end of the second branch path 17b is connected to the first pressure relief valve 18a. The terminal end of the third branch path 17c is connected to the second pressure relief valve 18b. The terminal end of the fourth branch path 17d is connected to the gas vent valve 19.

[0019] The expansion tank 50 is provided to store the liquid W1 expanded in the first circulation path portion 12A. The volume of the liquid W1 in the first circulation path portion 12A increases when the liquid W1 is heated in the heat exchanger 31 or the heating portion 13 and the temperature rises. The expansion tank 50 stores the liquid W1 by an amount corresponding to the increased volume, thereby suppressing the load on the piping that constitutes the first circulation path portion 12A. As will be described later, the expansion tank 50 is provided with a valve portion 59 (see FIG. 4 ) for draining the liquid W1 from the expansion tank 50. The valve portion 59 is opened by a maintenance worker when, for example, replacing the expansion tank 50.

[0020] The pressure relief valves 18a and 18b reduce the pressure in the first circulation path portion 12A when the pressure in the first circulation path portion 12A exceeds a predetermined threshold. By providing multiple pressure relief valves 18a and 18b in the branch path portion 17 branching from the first circulation path portion 12A, even if some pressure relief valves 18a are not operating, the other pressure relief valves 18b can reduce the pressure in the first circulation path portion 12A. In this embodiment, the pressure threshold set for the second pressure relief valve 18b is higher than the pressure threshold set for the first pressure relief valve 18a. The second pressure relief valve 18b is provided as a backup for the first pressure relief valve 18a. The first pressure relief valve 18a is disposed outside the housing 11, and the second pressure relief valve 18b is disposed inside the housing 11. When gas is mixed with the liquid W1 in the first circulation path portion 12A, the gas vent valve 19 separates the liquid W1 from the gas and removes the gas from the liquid W1.

[0021] Fig. 2 is a perspective view of the water heater main body 10. Fig. 3 is a front view of the water heater main body 10. As shown in Fig. 2, the water heater main body 10 has a generally rectangular parallelepiped shape that is long in the vertical direction Z. The housing 11 also has a generally rectangular parallelepiped box shape that is long in the vertical direction Z.

[0022] The housing 11 has a storage space A that houses each component of the water heater main body 10. The housing 11 has a top wall 11a located above the storage space A, a pair of side walls 11b located on the left (-Y side) and right side of the storage space A, a bottom wall 11c located below the storage space A, and a rear wall 11d located on the rear (-X side) of the storage space A. Although not shown in Figure 2, the housing 11 also has a front cover located on the front side (+X side) of the storage space A. The top wall 11a, the pair of side walls 11b, the bottom wall 11c, the rear wall 11d, and the front cover are separate entities.

[0023] As shown in Fig. 2, the control unit 70 has a substrate 72, multiple terminal blocks 73, and a support frame 71. The substrate 72 is arranged perpendicular to the front-rear direction X. Multiple elements are mounted on the substrate 72. The multiple terminal blocks 73 are arranged on the right side of the substrate 72. The multiple terminal blocks 73 are connected to the substrate 72 via wiring (not shown). Terminals of multiple wiring are connected to the terminal block 73. Note that the multiple wiring connected to the terminal block 73 is not shown in Fig. 2.

[0024] The support frame 71 supports a circuit board 72 and multiple terminal blocks 73. The support frame 71 has a support plate portion 71f, an upper frame portion 71a, a pair of side frame portions 71b, a pair of fixing portions 71c, and a lower frame portion 71d. The support plate portion 71f is plate-shaped and perpendicular to the front-rear direction X. The support plate portion 71f is rectangular when viewed from the front. The circuit board 72 and multiple terminal blocks 73 are fixed to the front surface of the support plate portion 71f. The upper frame portion 71a and the lower frame portion 71d are plate-shaped and perpendicular to the vertical direction Z. The pair of side frame portions 71b are plate-shaped and perpendicular to the left-right direction Y. The upper frame portion 71a protrudes forward from the upper end of the support plate portion 71f. The pair of side frame portions 71b protrude forward from the right and left ends of the support plate portion 71f, respectively. The lower frame portion 71d protrudes forward from the lower end of the support plate portion 71f.

[0025] The pair of fixing portions 71c are each plate-shaped and perpendicular to the front-rear direction X. The pair of fixing portions 71c each extend in the vertical direction Z. The pair of fixing portions 71c are arranged side by side in the left-right direction Y. The right (+Y side) fixing portion 71c protrudes to the right from the front end of the right side frame portion 71b. The right fixing portion 71c is screwed to the front edge of the right side wall portion 11b of the housing 11. The left (-Y side) fixing portion 71c protrudes to the left from the front end of the left side frame portion 71b. The left fixing portion 71c is screwed to the front edge of the left side wall portion 11b of the housing 11. In this way, the support frame 71 is fixed to the housing 11.

[0026] The expansion tank 50 is located at the top of the storage space A. That is, the expansion tank 50 is located above the components of the water heater main body 10. The expansion tank 50 is disposed below the top wall 11a of the housing 11 and along the top wall 11a.

[0027] Figure 4 is a perspective view of the water heater body 10 with a portion of the housing 11 removed. As shown in Figure 4, the expansion tank 50 has an upper member 51, a lower member 52, and a first buffer material 50C. A storage space B for storing expanded liquid is provided inside the expansion tank 50. The upper member 51 and the lower member 52 are connected to each other to form the storage space B. The upper member 51 covers the storage space B from above. The lower member 52 covers the storage space B from below. The upper member 51 and the lower member 52 are made of a metal material to ensure sufficient heat resistance.

[0028] The upper member 51 has a concave upper member body 51a that opens downward and a first flange (flange) 51f that surrounds the downward opening. The lower member 52 has a concave lower member body 52a that opens upward and a second flange (flange) 52f that surrounds the upward opening. The openings of the upper member body 51a and the lower member body 52a are arranged opposite each other to form the storage space B. The first flange 51f and the second flange 52f face each other in the vertical direction Z. The first flange 51f and the second flange 52f are connected to each other by a joining means such as welding to form a connecting flange (flange) 50f.

[0029] The first cushioning material 50C is made of, for example, a porous resin material. The first cushioning material 50C is an elastic member that is compressed to conform to the contours of an object when subjected to force from the object. The first cushioning material 50C is attached to the connecting flange 50f. The first cushioning material 50C is formed with a C-shaped cross section. The first cushioning material 50C surrounds the upper, lower, and tip surfaces of the connecting flange 50f. The first cushioning material 50C is adhesively fixed to the upper, lower, and tip surfaces of the connecting flange 50f.

[0030] The expansion tank 50 is provided with a valve portion 59. The valve portion 59 protrudes forward from the surface of the expansion tank 50 facing the front. The valve portion 59 is located at the center of the expansion tank 50 in the left-right direction Y. The valve portion 59 is provided on the upper member main body 51a. In other words, the valve portion 59 is located above the connecting flange portion 50f. The valve portion 59 has a knob shape that can be manually rotated around a central axis extending in the front-rear direction X. A maintenance worker can rotate the valve portion 59 to drain the liquid stored in the storage space B.

[0031] <Tank Support> A tank support 10A is arranged in the storage space A of the housing 11. That is, the water heater main body 10 has the tank support 10A. The tank support 10A supports the expansion tank 50 within the housing 11. The tank support 10A has two first support parts 90 and one second support part 80. The two first support parts 90 and the one second support part 80 are each fixed to the housing 11. That is, the tank support part 10A is fixed to the housing 11.

[0032] The two first support portions 90 are located rearward relative to the expansion tank 50. The two first support portions 90 are located on both sides of the expansion tank 50 in the left-right direction Y. The second support portion 80 is located frontward relative to the expansion tank 50. The second support portion 80 is located in the center of the expansion tank 50 in the left-right direction Y.

[0033] <First Support Portion> The two first support portions 90 have shapes that are symmetrical to each other when viewed from the front-rear direction X. In the following explanation, of the two first support portions 90, the explanation of each portion will focus on only one first support portion 90 located on the left side (-Y side), and an explanation of the other first support portion 90 located on the right side (+Y side) will be omitted.

[0034] Fig. 5 is an enlarged view of region V in Fig. 4. Fig. 6 is an exploded perspective view of the first support portion 90. As shown in Fig. 6, the first support portion 90 has a base portion 97, a first support 91, and a second buffer material 90C. The base portion 97 and the first support 91 are each a metal plate member formed by press working. The second buffer material 90C is made of the same material as the first buffer material 50C.

[0035] The base portion 97 has a first fixing plate portion 97a, a second fixing plate portion 97b, two connecting plate portions 97c, and a first support plate portion 97d. The first fixing plate portion 97a, the second fixing plate portion 97b, and the first support plate portion 97d are plate-shaped and perpendicular to the front-rear direction X, and are arranged along the rear wall portion 11d of the housing 11. The first fixing plate portion 97a is located above the first support plate portion 97d. The second fixing plate portion 97b is located below the first support plate portion 97d. The first fixing plate portion 97a and the second fixing plate portion 97b are welded and fixed to the rear wall portion 11d. This fixes the first support portion 90 to the housing 11.

[0036] The first support plate 97d is located further forward than the first fixing plate 97a and the second fixing plate 97b. The first support plate 97d has a third support surface 97f facing forward. The third support surface 97f is a flat surface perpendicular to the front-rear direction X. The second buffer material 90C is adhesively fixed to the front side of the third support surface 97f. The first support plate 97d also has two screw holes 97h. The screw holes 97h are provided in an area of ​​the first support plate 97d to the left (-Y side) of the area where the second buffer material 90C is fixed.

[0037] The two connecting plate portions 97c are plate-shaped and perpendicular to the vertical direction Z. The two connecting plate portions 97c are arranged side by side in the vertical direction Z. The upper connecting plate portion 97c connects the lower end of the first fixing plate portion 97a to the upper end of the first support plate portion 97d. The lower connecting plate portion 97c connects the upper end of the second fixing plate portion 97b to the lower end of the first support plate portion 97d.

[0038] The first support 91 has two third fixing plate portions 96, an upper guide plate portion 94, a side guide plate portion 93, and a second support plate portion 92. The first support 91 protrudes forward from a third support surface 97f of the base portion 97.

[0039] The two third fixing plate portions 96 are plate-shaped and perpendicular to the front-rear direction X. The two third fixing plate portions 96 are arranged side by side in the vertical direction Z. Each of the two third fixing plate portions 96 is provided with an insertion hole 96h. A fixing screw 99 is inserted into the insertion hole 96h and fastened to the screw hole 97h. In this way, the first support body 91 is fixed to the base portion 97.

[0040] The upper guide plate portion 94 and the second support plate portion 92 are plate-shaped and perpendicular to the vertical direction Z. The side guide plate portion 93 is plate-shaped and perpendicular to the left-right direction Y. The upper guide plate portion 94 and the second support plate portion 92 face each other in the vertical direction Z with a gap between them. The upper guide plate portion 94 is located above the second support plate portion 92. The upper guide plate portion 94 is connected to the lower end of the upper of the two third fixing plate portions 96. The upper guide plate portion 94 is substantially triangular when viewed in the vertical direction Z.

[0041] The second support plate portion 92 is connected to the upper end of the lower of the two third fixed plate portions 96. The second support plate portion 92 has a facing portion 92c that overlaps with the upper guide plate portion 94 when viewed from the vertical direction Z, and a rail portion 92b that extends forward from the facing portion 92c. The facing portion 92c is substantially triangular when viewed from the vertical direction Z. The rail portion 92b is rectangular with its longitudinal direction aligned with the front-to-rear direction X. The second support plate portion 92 has a first support surface 92a that faces upward. The first support surface 92a is a flat surface that is perpendicular to the vertical direction Z. The first support surface 92a is provided on the entire second support plate portion 92, including the facing portion 92c and the rail portion 92b.

[0042] The side guide plate portion 93 has a rectangular shape with its longitudinal direction in the front-rear direction X. The side guide plate portion 93 connects the left end (-Y side) of the upper guide plate portion 94 to the left end (-Y side) of the second support plate portion 92. As a result, the upper guide plate portion 94, the side guide plate portion 93, and the second support plate portion 92 are configured in a C-shape that opens to the right (+Y side). The side guide plate portion 93 extends forward beyond the front end of the upper guide plate portion 94. The side guide plate portion 93 is connected to the entire length of the second support plate portion 92 in the front-rear direction X, including the opposing portion 92c and the rail portion 92b.

[0043] As shown in FIG. 5 , the connecting flange 50f of the expansion tank 50 is inserted into an opening surrounded by the upper guide plate 94, the side guide plate 93, and the second support plate 92 of the first support part 90. The connecting flange 50f is mounted on the first support surface 92a of the second support plate 92. That is, the first support part 90 supports the expansion tank 50 from below on the first support surface 92a. As described above, the connecting flange 50f is covered by the first buffer material 50C. Therefore, the first buffer material 50C is disposed between the first support surface 92a and the expansion tank 50. The first buffer material 50C is compressed in the vertical direction Z between the first support surface 92a and the connecting flange 50f.

[0044] The upper guide plate 94 covers the connecting flange 50f from above via a gap. The side guide plate 93 covers the connecting flange 50f from the left side (-Y side) via a gap. As a result, the upper guide plate 94 and the side guide plate 93 guide the connecting flange 50f, facilitating the assembly process of the expansion tank 50 to the first support part 90.

[0045] A base portion 97 is disposed behind the expansion tank 50. A third support surface 97f of the base portion 97 faces the expansion tank 50 in the front-to-rear direction X. The expansion tank 50 is pressed against the third support surface 97f while mounted on the first support surface 92a. That is, the first support portion 90 supports the expansion tank 50 from the rear side at the third support surface 97f. As described above, the first buffer material 50C is fixed to the connecting flange 50f of the expansion tank 50. Furthermore, the second buffer material 90C is fixed to the first support surface 92a. The connecting flange 50f and the third support surface 97f are in contact with each other, sandwiching the first buffer material 50C and the second buffer material 90C therebetween. The first buffer material 50C and the second buffer material 90C are compressed in the front-to-rear direction X between the connecting flange 50f and the third support surface 97f.

[0046] <Second Supporting Part> Fig. 7 is a perspective view of the second supporting part 80. Fig. 8 is a perspective view of the water heater body 10 around the second supporting part 80, with the water heater body 10 cut along VIII-VIII in Fig. 3 .

[0047] 7, the second support portion 80 includes a second support member 89, a pair of third buffer members 82C, and a fourth buffer member 83C. The second support member 89 is a metal plate member formed by press working. The third buffer member 82C and the fourth buffer member 83C are made of the same material as the first buffer member 50C and the second buffer member 90C.

[0048] The second support 89 has a main body plate 81, a pair of reinforcing plate portions 84, a pair of fixing pieces 85, a pair of first protruding pieces 82, and a second protruding piece 83. The main body plate 81 is plate-shaped and perpendicular to the front-rear direction X. The main body plate 81 has a substantially rectangular shape when viewed in the front-rear direction X. The main body plate 81 has a protruding portion 81a located at the lower end. The protruding portion 81a is located approximately in the center of the main body plate 81 in the left-right direction Y. The main body plate 81 also has a through hole 81h that penetrates the main body plate 81 in the thickness direction. The through hole 81h has a substantially rectangular shape when viewed in the front-rear direction X.

[0049] The pair of reinforcing plate portions 84 are plate-shaped and perpendicular to the left-right direction Y. The pair of reinforcing plate portions 84 are formed by bending forward from both end portions of the main body plate portion 81 in the left-right direction Y. The fixing pieces 85 are plate-shaped and perpendicular to the vertical direction Z. The pair of fixing pieces 85 are connected to the lower end portions of the reinforcing plate portions 84 located on both sides in the left-right direction Y, respectively.

[0050] The pair of first protruding pieces 82 are arranged side by side in the left-right direction Y. Each of the pair of first protruding pieces 82 is connected to the upper edge of the main body plate portion 81. The first protruding piece 82 has a first rear protruding portion 82b and an upper protruding portion 82a. The first rear protruding portion 82b is plate-shaped and perpendicular to the vertical direction Z. The upper protruding portion 82a is plate-shaped and perpendicular to the front-rear direction X. The first rear protruding portion 82b and the upper protruding portion 82a are formed by being bent into an L-shape when viewed from the left-right direction Y. The first rear protruding portion 82b extends rearward from the main body plate portion 81. The first rear protruding portion 82b has a second support surface 82g facing downward. The upper protruding portion 82a extends upward from the rear end of the first rear protruding portion 82b. The upper protruding portion 82a has a fourth support surface 82f facing rearward. That is, the first protruding piece 82 has a second support surface 82g and a fourth support surface 82f. A third buffer material 82C is fixed to the first protruding piece 82. The third buffer material 82C is adhesively fixed to the second support surface 82g and the fourth support surface 82f.

[0051] The second protruding piece 83 is connected to the upper edge of the through-hole 81h of the main body plate portion 81. The second protruding piece 83 has a second rear protruding portion 83b and a downward protruding portion 83a. The second rear protruding portion 83b is plate-shaped and perpendicular to the vertical direction Z. The downward protruding portion 83a is plate-shaped and perpendicular to the front-rear direction X. The second rear protruding portion 83b and the downward protruding portion 83a are formed by bending them into an L-shape when viewed from the left-right direction Y. The second rear protruding portion 83b extends rearward from the main body plate portion 81. The downward protruding portion 83a extends downward from the rear end of the second rear protruding portion 83b. The downward protruding portion 83a has a fourth support surface 83f facing rearward. That is, the second protruding piece 83 has the fourth support surface 83f. A fourth buffer material 83C is fixed to the second protruding piece 83. The fourth buffer material 83C is adhesively fixed to the fourth support surface 83f and the surface facing upward of the second rearward protruding portion 83b.

[0052] As shown in Fig. 8, the lower surface of the fixing piece 85 is mounted on the upper surface of the upper frame portion 71a of the support frame 71. The fixing piece 85 is joined to the upper frame portion 71a by joining means such as welding. As a result, the second support portion 80 is fixed to the upper end portion of the support frame 71. As shown in Fig. 2, the support frame 71 is fixed to the two side wall portions 11b of the housing 11. In other words, the second support portion 80 is fixed to the housing 11 via the support frame 71. The support frame 71 is fixed to the housing 11 with the second support portion 80 previously welded and fixed thereto.

[0053] 8, the first protruding piece 82 is located above the connecting flange 50f of the expansion tank 50. The second protruding piece 83 is located below the connecting flange 50f. The second support surface 82g of the first protruding piece 82 contacts the upper surface of the connecting flange 50f from above, with the first buffer material 50C and the third buffer material 82C interposed between them. The first buffer material 50C and the third buffer material 82C are compressed in the vertical direction Z between the connecting flange 50f and the second support surface 82g.

[0054] The fourth support surface 82f of the first protruding piece 82 contacts the front-facing surface of the expansion tank 50 from the front side, via the third buffer material 82C. The third buffer material 82C is compressed in the front-to-rear direction X between the front surface of the expansion tank 50 and the fourth support surface 82f. The fourth support surface 83f of the second protruding piece 83 contacts the front-facing surface of the expansion tank 50 from the front side, via the fourth buffer material 83C. The fourth buffer material 83C is compressed in the front-to-rear direction X between the front surface of the expansion tank 50 and the fourth support surface 82f.

[0055] The second support portion 80 supports the expansion tank 50 from above at the second support surface 82g, and supports the expansion tank 50 from the front at the fourth support surfaces 82f and 83f. In this embodiment, the fourth support surfaces 82f and 83f support the upper and lower regions of the expansion tank 50, respectively, with the connecting flange 50f in between.

[0056] As shown in Figure 8, the valve portion 59 of the expansion tank 50 is disposed between the pair of first protruding pieces 82 in the left-right direction Y. The upper edge of the second support portion 80 is located below the valve portion 59 in the region between the pair of first protruding pieces 82. Therefore, the second support portion 80 is located below the valve portion 59. According to this embodiment, the second support portion 80 is not disposed above the valve portion 59, making it easier for maintenance workers to access the valve portion 59 from above. According to this embodiment, the second support portion 80 is less likely to interfere with the operation of the valve portion 59, making it easier for maintenance workers to operate the valve portion 59.

[0057] <Summary> As shown in FIG. 1 , the water heater 100 of the above-described embodiment includes a housing 11, a heating unit 13 housed within the housing 11, an expansion tank 50 housed within the housing 11, a first circulation path 12A passing through the heating unit 13, a branch path 17 branching from the first circulation path 12A and leading to the expansion tank 50, and a tank support 10A (see FIG. 4 ) supporting the expansion tank 50 within the housing 11. As shown in FIG. 4 , the tank support 10A includes a first support 90 located rearward of the expansion tank 50 and a second support 80 located forward of the expansion tank 50. As shown in FIG. 5 , the first support 90 includes a first support surface 92a that supports the expansion tank 50 from below. As shown in FIG. 8 , the second support 80 includes a second support surface 82g that supports the expansion tank 50 from above. With this configuration, the expansion tank 50 is supported from both sides in the vertical direction Z by the first support surface 92a and the second support surface 82g. This prevents the expansion tank 50 from rattling inside the housing 11 and prevents the expansion tank 50 from vibrating due to resonance with vibrations generated when the pump 15 or other components are driven. This allows for a quieter water heater 100. With this configuration, the tank support 10A secures the expansion tank 50 by pressing the first support surface 92a and the second support surface 82g against the surface of the expansion tank 50 from both sides in the vertical direction Z. This eliminates the need for complicated procedures such as screw fastening when securing the expansion tank 50, simplifying the assembly process of the water heater 100. This prevents rattling of the expansion tank in the water heater 100 without complicating the assembly process.

[0058] In the water heater 100 according to the above embodiment, as shown in Fig. 5, a first cushioning material 50C is disposed between the first support surface 92a and the expansion tank 50. Furthermore, as shown in Fig. 8, a first cushioning material 50C and a third cushioning material 82C are disposed between the second support surface 82g and the expansion tank 50. With this configuration, errors in the assembly dimensions of the first support surface 92a and the second support surface 82g can be absorbed by compression of the cushioning materials 50C and 82C, and rattle of the expansion tank 50 can be more effectively suppressed.

[0059] As shown in Fig. 5, in the water heater 100 according to the above embodiment, the first support member 90 has a third support surface 97f that supports the expansion tank 50 from the rear side. As shown in Fig. 8, the second support member 80 has fourth support surfaces 82f, 83f that support the expansion tank 50 from the front side. With this configuration, the expansion tank 50 is further supported from both sides in the front-rear direction X by the third support surface 97f and the fourth support surfaces 82f, 83f. This makes it possible to suppress rattling of the expansion tank 50 in the front-rear direction X inside the housing 11.

[0060] As shown in Fig. 5, in the water heater 100 of the above-described embodiment, a first cushioning material 50C and a second cushioning material 90C are disposed between the third support surface 97f and the expansion tank 50. As shown in Fig. 8, a third cushioning material 82C or a fourth cushioning material 83C is disposed between the fourth support surfaces 82f, 83f and the expansion tank 50. With this configuration, errors in the assembly dimensions of the third support surface 97f and the fourth support surfaces 82f, 83f can be absorbed by compression of the cushioning materials 50C, 90C, 82C, 83C, and rattle of the expansion tank 50 in the front-to-rear direction X can be more suitably suppressed.

[0061] As shown in FIG. 4 , in the water heater 100 according to the above embodiment, the expansion tank 50 includes an upper member 51 and a lower member 52 that form a storage space B. The upper member 51 and the lower member 52 each have flanges 51f, 52f that are connected to each other and face each other in the vertical direction Z. A first support member 90 supports a connecting flange 50f, to which the flanges 51f, 52f are connected, from below. A second support member 80 supports the connecting flange 50f from above. Generally, the expansion tank 50 is made of a metal material to ensure high heat resistance. For this reason, a typical expansion tank 50 includes a connecting flange 50f that is provided when the lower member 52 and the upper member 51 are connected to each other. With this configuration, the expansion tank 50 can be supported using the connecting flange 50f of the expansion tank 50. Therefore, the manufacturing costs of the expansion tank 50 can be reduced compared to when a separate supported member that is supported by the first support portion 90 and the second support portion 80 is provided on the expansion tank 50 .

[0062] As shown in FIG. 4 , the water heater 100 of the above-described embodiment includes a control unit 70 housed inside the housing 11. As shown in FIG. 4 , the control unit 70 includes a substrate 72 and a support frame 71 that supports the substrate 72. The expansion tank 50 includes a manually operable valve unit 59 that protrudes forward from the front-facing surface of the expansion tank 50. The second support unit 80 is fixed to the upper end of the support frame 71 and is located below the valve unit 59. With this configuration, the second support unit 80 is less likely to interfere with manual operation of the valve unit 59. Furthermore, because a maintenance worker is less likely to come into contact with the second support unit 80 when manually operating the valve unit 59, measures such as protecting the edge portion of the second support unit 80 are not required, thereby reducing the manufacturing cost of the water heater 100.

[0063] As shown in FIG. 4 , in the water heater 100 of the above-described embodiment, the tank support 10A has two first support portions 90 and one second support portion 80. The two first support portions 90 are located on both sides of the expansion tank 50 in the left-right direction Y. The one second support portion 80 is located in the center of the expansion tank 50 in the left-right direction Y. With this configuration, the tank support 10A supports both ends of the expansion tank 50 in the left-right direction Y at the rear and supports the center of the expansion tank 50 in the left-right direction Y at the front, thereby supporting the expansion tank 50 at three points that are sufficiently spaced apart from one another. This allows the tank support 10A to stably support the expansion tank 50.

[0064] The configurations and methods described in this specification can be combined as appropriate within a range that does not contradict each other. For example, in the above-mentioned embodiment, both a heat exchanger and a heating unit (heater) are provided as devices for heating the liquid in the first circulation path section, but since both devices function as a "heating unit" that heats the liquid in the first circulation path section, either one of them may be defined as the "heating unit."

[0065] DESCRIPTION OF SYMBOLS 10...water heater main body, 10A...tank support portion, 11...housing, 12A...first circulation path portion (circulation path portion), 13...heating portion, 17...branch path portion, 50...expansion tank, 50C...cushioning material, 51...upper member, 50f, 51f, 52f...flange portion, 52...lower member, 59...valve portion, 70...control portion, 71...support frame, 72...substrate, 80...second support portion, 82f, 83f...fourth support surface, 82g...second support surface, 90...first support portion, 92a...first support surface, 97f...third support surface, 100...water heater, B...storage space, X...front-to-back direction (first direction), +X side...front side (second side), -X side...rear side (first side), Y...left-to-right direction (second direction), Z...vertical direction

Claims

**Claim 1** A casing, a heating unit housed inside the casing, an expansion tank housed inside the casing, a circulation path unit passing through the heating unit, a branch path unit branching from the circulation path unit and connected to the expansion tank, a tank support unit that supports the expansion tank inside the casing, and a control unit housed inside the casing, and the tank support unit has a first support unit positioned on a first side in a first direction orthogonal to the vertical direction with respect to the expansion tank, and a second support unit positioned on a second side in the first direction with respect to the expansion tank, the first support unit has a first support surface that supports the expansion tank from below, the second support unit has a second support surface that supports the expansion tank from above, the control unit has a substrate, and a support frame that supports the substrate, the expansion tank has a manually operable valve unit that protrudes toward the second side from a surface facing the second side of the expansion tank, the second support unit is fixed to an upper end portion of the support frame and is positioned below the valve unit, a water heater. **Claim 2** A buffer material is disposed between the first support surface and the expansion tank, and a buffer material is disposed between the second support surface and the expansion tank, The water heater according to claim 1. **Claim 3** The first support unit has a third support surface that supports the expansion tank from the first side, the second support unit has a fourth support surface that supports the expansion tank from the second side, The water heater according to claim 1. **Claim 4** A buffer material is disposed between the third support surface and the expansion tank, and a buffer material is disposed between the fourth support surface and the expansion tank, The water heater according to claim 3. **Claim 5** The expansion tank has an upper member and a lower member that form a storage space, the upper member and the lower member each have a flange portion that is connected to face each other in the vertical direction, the first support unit supports the connected flange portion from below, the second support unit supports the connected flange portion from above, The water heater according to claim 1. **Claim 6** The tank support unit has two of the first support units, and one of the second support units, the two first support units are positioned on both sides in a second direction orthogonal to both the vertical direction and the first direction with respect to the expansion tank, the one second support unit is positioned at the center in the second direction with respect to the expansion tank, The water heater according to any one of claims 1 to 5.