Hot water storage type water heater

Abstract

To provide a hot water storage type water heater capable of reducing the number of components.SOLUTION: A hot water storage type water heater 1 includes: a tank 10 for storing hot water; a hot water supply pipeline 20 for supplying hot water to the outside from the tank 10; a first water supply pipeline 30-1 for supplying water to the tank 10 from the outside; a second water supply pipeline 30-2 connected between the first water supply pipeline 30-1 and the tank 10, and for supplying water from the first water supply pipeline 30-1 to the tank 10; a pump 40 for allowing the water to flow back to the second water supply pipeline 30-2 by sucking up the water from the tank 10; a boiling pipeline 50 connected to the second water supply pipeline 30-2 and the tank 10, and for returning the water which has been sucked up by the pump 40 and has flowed in the second water supply pipeline 30-2 to the tank 10; a heat exchanger 60 for performing heat exchange in order to heat the water flowing in the boiling pipeline 50; and a branch part 70 for connecting the first water supply pipeline 30-1, the second water supply pipeline 30-2, and the boiling pipeline 50.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a storage type water heater. [Background technology]

[0002] Patent Document 1 discloses a storage-type water heater that can store hot water and supply it. This storage-type water heater includes a hot water storage tank that stores hot water and a heat pump unit that heats the hot water stored in the hot water storage tank. The heat pump unit performs a boiling operation to heat the hot water stored in the hot water storage tank. Pipes for a boiling circuit are connected to the top and bottom of the hot water storage tank via the heat pump unit. Furthermore, pipes for a water supply circuit that supplies low-temperature water are connected to the bottom of the hot water storage tank. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-228214 Summary of the Invention [Problem to be solved by the invention]

[0004] In a storage-type hot water heater, both the heating circuit pipe and the water supply circuit pipe are connected to the bottom of the hot water storage tank. Therefore, the bottom of the hot water storage tank needs separate connection ports for connecting both the heating circuit pipe and the water supply circuit pipe. This increases the number of parts.

[0005] The present disclosure has been made in light of the above-mentioned circumstances, and aims to provide a storage type hot water heater that can reduce the number of parts. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the hot water storage type water heater of the present disclosure comprises a tank for storing hot water, a hot water supply pipe for supplying hot water from the tank to the outside, a first water supply pipe for supplying water from the outside to the tank, a second water supply pipe connected between the first water supply pipe and the tank and supplying water from the first water supply pipe to the tank, a pump for drawing water from the tank and causing it to flow back into the second water supply pipe, a boiling pipe connected to the second water supply pipe and the tank and returning water that has been drawn up by the pump and flowed through the second water supply pipe to the tank, a heat exchanger that performs heat exchange to heat the water flowing through the boiling pipe, and a branch section connecting the first water supply pipe, the second water supply pipe, and the boiling pipe. [Effects of the Invention]

[0007] The hot water storage type water heater according to the present disclosure includes a second water supply pipe that supplies water from the first water supply pipe to the tank, and a pump that draws water from the tank and causes the water to flow back into the second water supply pipe. As a result, according to the present disclosure, it is possible to provide a hot water storage type water heater that can reduce the number of parts. [Brief explanation of the drawings]

[0008] [Figure 1] Configuration diagram of a hot water storage type water heater according to embodiment 1 [Figure 2] A configuration diagram showing a part of a hot water storage type water heater according to the first embodiment. [Figure 3] FIG. 1 is a configuration diagram (part 1) for explaining the operation of the hot water storage type water heater according to the first embodiment. [Figure 4] 1 is a block diagram (part 2) illustrating the operation of the hot water storage type water heater according to the first embodiment. [Figure 5] 1 is a block diagram (part 3) illustrating the operation of the hot water storage type water heater according to the first embodiment. [Figure 6] FIG. 1 is a structural diagram showing a part of a hot water storage type water heater according to Comparative Example 1. [Figure 7] FIG. 10 is a structural diagram showing a part of a hot water storage type water heater according to Comparative Example 2. [Figure 8] A configuration diagram showing a part of a hot water storage type water heater according to embodiment 2. [Figure 9] A configuration diagram showing a part of a hot water storage type water heater according to a third embodiment. [Figure 10] A configuration diagram showing a part of a hot water storage type water heater according to embodiment 4. [Figure 11] A configuration diagram showing a part of a hot water storage type water heater according to embodiment 5. [Figure 12] A configuration diagram showing a part of a hot water storage type water heater according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiment 1 The hot water storage type water heater 1 according to the first embodiment will be described below with reference to the drawings. In each drawing, the same reference numerals indicate the same or corresponding parts. The up-down direction in each drawing is the same as the height direction D1 of the hot water storage type water heater 1.

[0010] As shown in FIG. 1, the hot water storage type water heater 1 includes a tank 10 for storing hot water, and a heating circuit 90 for performing a boiling operation for heating the water stored in the tank 10.

[0011] The heating circuit 90 includes a pump 91, a flow meter 92, a heat exchanger 93, an auxiliary heat source 94, a three-way valve 95, and a circulation pipe 90a that connects these components in a circular configuration. The fluid that flows through the circulation pipe 90a is, for example, a liquid, specifically, water. A heater supply pipe 90b and a heater return pipe 90c are also connected to the circulation pipe 90a.

[0012] For example, during a boiling operation, the pump 91 circulates the fluid flowing in the circulation pipe 90a. Specifically, the pump 91 circulates the fluid flowing in the circulation pipe 90a by sending the fluid from the pump 91 to the heat exchanger 93.

[0013] The flow meter 92 measures the flow rate of the fluid flowing through the circulation pipe 90a. The flow meter 92 is provided downstream of the pump 91 during the boiling operation. Therefore, the flow meter 92 measures the flow rate of the fluid sent out from the pump 91 by the pump 91.

[0014] The heat exchanger 93 exchanges heat between the fluid flowing through the circulation pipe 90a and the refrigerant flowing through the heat pump pipe 90d. In this way, the heat exchanger 93 heats the fluid flowing through the circulation pipe 90a. For example, the circulation pipe 90a and the heat pump pipe 90d penetrate the heat exchanger 93. For example, the heat exchanger 93 includes a plurality of fins. The circulation pipe 90a and the heat pump pipe 90d are provided so as to penetrate the plurality of fins. The heat exchanger 93 is disposed, for example, outdoors. However, this is not limited thereto. The heat exchanger 93 may also be disposed indoors. The heat exchanger 93 may also be installed outside the device or inside the device. The location of the heat exchanger 93 is appropriately selected depending on the model of the hot water storage type water heater 1.

[0015] The auxiliary heat source 94 provides auxiliary heating to the fluid heated by the heat exchanger 93. The auxiliary heat source 94 is, for example, a booster heater that can be attached to existing piping. However, the auxiliary heat source 94 is not limited to this. The auxiliary heat source 94 may be something other than a booster heater.

[0016] The three-way valve 95 switches the direction in which the fluid is sent out. The three-way valve 95 is, for example, a ball valve. However, the present invention is not limited to this. The three-way valve 95 may be a switching valve other than a ball valve. For example, the three-way valve 95 may be a solenoid valve.

[0017] The heater supply pipe 90b is a pipe for sending heated fluid to the heater side. This heater supply pipe 90b is connected to the circulation pipe 90a via a three-way valve 95.

[0018] The heater return pipe 90c is a pipe through which the fluid sent from the heater side flows, and is connected to the circulation pipe 90a.

[0019] A refrigerant is sealed in the heat pump pipe 90d. The heat pump pipe 90d is connected to an outdoor unit. The outdoor unit includes, for example, a compressor, a heat exchanger that exchanges heat between air and the refrigerant, and an expansion valve.

[0020] 1 and 2, the hot water storage type water heater 1 includes a tank 10, a hot water supply pipe 20, a first water supply pipe 30-1, a second water supply pipe 30-2, a pump 40, a boiling pipe 50, a heat exchanger 60, a branching section 70, a scale catcher 80, and a control section 100. These components of the hot water storage type water heater 1 are covered by a housing 1a and placed indoors.

[0021] Tank 10 is formed as a vertically elongated sealed tank that stores hot water. Specifically, tank 10 has a cylindrical tank body 11, an upper tank portion 12, and a lower tank portion 13. In this embodiment, tank body 11 is formed in a cylindrical shape. However, this is not limited to this, and tank body 11 may be formed in a shape other than a cylindrical shape.

[0022] The tank upper portion 12 is a lid portion that covers an upper opening in the height direction D1 of the tank body portion 11. The tank upper portion 12 has a curved surface that bulges upward. Upper inlets and outlets 10a and 10b are formed in the curved surface of the tank upper portion 12. A boiling pipe 50 is connected to and passes through the upper inlet and outlet 10b.

[0023] The tank lower part 13 is a bottom part that covers the lower opening in the height direction D1 of the tank body part 11. The tank lower part 13 is supported by legs, for example, at a distance from the installation surface S of the hot water storage type water heater 1 or the bottom surface of the housing 1a.

[0024] The tank 10 formed as described above further has a lower port 10c and a drain valve port 10e.

[0025] The hot water supply pipe 20 supplies hot water from the tank 10 to the outside. One end of the hot water supply pipe 20 is connected to the upper inlet / outlet 10a of the tank upper part 12. In addition, one end of the hot water supply pipe 20 is arranged to protrude into the inside of the tank 10. As a result, the hot water supply pipe 20 is formed to include internal piping 25, a part of which is arranged inside the tank 10. The other end of the hot water supply pipe 20 is connected, for example, to an openable and closable hot water tap. The hot water from the tank 10 is supplied to the outside via the hot water tap.

[0026] The first water supply pipe 30-1 supplies water from the outside to the tank 10. The first water supply pipe 30-1 is connected to a branch portion .

[0027] The second water supply pipe 30-2 is connected between the first water supply pipe 30-1 and the tank 10, and supplies water supplied from the first water supply pipe 30-1 to the tank 10. More specifically, one end 30-2a of the second water supply pipe 30-2 is connected to the first water supply pipe 30-1 via a branch 70. The other end 30-2b of the second water supply pipe 30-2 is connected to and penetrates the lower port 10c of the tank 10. The opening of the other end 30-2b of the second water supply pipe 30-2 that penetrates the lower port 10c is located near the bottom of the tank 10. As a result, the second water supply pipe 30-2 is formed to include an internal pipe 35, a portion of which is located inside the tank 10. The second water supply pipe 30-2 is also formed as a pipe separate from the first water supply pipe 30-1. 1 and 2, the lower access port 10c is formed in the tank body 11 of the tank 10. However, this is not limited to this. The lower access port 10c may be formed in a location other than the tank body 11 of the tank 10. For example, the lower access port 10c may be formed in the tank lower portion 13 of the tank 10.

[0028] The pump 40 is installed in the boiling piping 50. The pump 40 sucks up water from the tank 10 and causes the water to flow back into the second water supply piping 30-2. In the first embodiment, the pump 40 is arranged so that a position P2 in the height direction D1 is higher than a position P1 of the upper end of the tank 10. More specifically, the lower end of the pump 40 is arranged higher in the height direction D1 than a position P1 of the upper end of the tank 10. The pump 40 is controlled by, for example, the control unit 100.

[0029] One end 51 of the boiling pipe 50 is connected to the second water supply pipe 30-2 via a branching section 70. The boiling pipe 50 is a pipe that is sucked up by a pump 40 to cause water from the tank 10 to flow back into the second water supply pipe 30-2, and then returns the water to the tank 10. The other end 52 of the boiling pipe 50 is connected to the upper tank portion 12 of the tank 10. An opening 52a of the other end 52 of the boiling pipe 50 is disposed so as to protrude into the interior of the tank 10. As a result, the boiling pipe 50 is formed to include an internal pipe 55, a portion of which is disposed inside the tank 10. The boiling pipe 50 is also formed as a pipe separate from the first water supply pipe 30-1 and the second water supply pipe 30-2.

[0030] The boiling pipe 50 is also provided with a pressure relief valve 54 and a drain plug (not shown). The pressure relief valve 54 is used to adjust the internal pressure in the boiling pipe 50 when high pressure builds up inside the boiling pipe 50. An expansion tank may also be installed in the boiling circuit formed by the second water supply pipe 30-2, the branch section 70, and the boiling pipe 50. In this case, the pressure relief valve 54 may be used to adjust the internal pressure in the boiling circuit when high pressure builds up inside the expansion tank. The expansion tank may be installed outside the housing 1a of the hot water storage type water heater 1, or may be installed inside the housing 1a. The expansion tank may be installed outdoors or indoors.

[0031] The heat exchanger 60 exchanges heat between the water flowing through the boiling pipe 50 and the fluid flowing through the circulation pipe 90a. In this way, the heat exchanger 60 heats the water flowing through the boiling pipe 50. For example, the boiling pipe 50 and the circulation pipe 90a penetrate the heat exchanger 60. For example, the heat exchanger 60 is provided with a plurality of fins. The boiling pipe 50 and the circulation pipe 90a are provided so as to penetrate the plurality of fins. In the first embodiment, the heat exchanger 60 is disposed such that a position P2 in the height direction D1 is higher than a position P1 of the upper end of the tank 10. Specifically, the lower end of the heat exchanger 60 is disposed higher in the height direction D1 than a position P1 of the upper end of the tank 10.

[0032] The branching section 70 interconnects three pipes: the first water supply pipe 30-1, the second water supply pipe 30-2, and the boiling water pipe 50. Specifically, the branching section 70 has a first connection port 71, a second connection port 72, and a third connection port 73, which are open in three directions. The opening direction of the first connection port 71 and the opening direction of the second connection port 72 are on the same axis. The first connection port 71 is connected to the first water supply pipe 30-1, and the second connection port 72 is connected to the second water supply pipe 30-2. The first connection port 71, to which the first water supply pipe 30-1 is connected, opens within a range θ of 0° to 180° with respect to a plane S2 parallel to a horizontal plane perpendicular to the height direction D1. In other words, the outward normal of the opening plane faces upward from the horizontal. Therefore, the range θ is within the range of the elevation angle, and the first connection port 71 opens within the range of the elevation angle with respect to the parallel plane S2. In the present embodiment 1, the branching portion 70 is not a closable three-way valve but a T-shaped three-way joint. In the present embodiment 1, the position P3 of the branching portion 70 in the height direction D1 is located lower than the position P2 of the heat exchanger 60 and higher than the position P4 of the lower end of the tank 10. Specifically, the upper end of the branching portion 70 is located lower in the height direction D1 than the lower end of the heat exchanger 60. The lower end of the branching portion 70 is located higher in the height direction D1 than the lower end of the tank 10.

[0033] The scale catcher 80 is installed on the boiling piping 50. This scale catcher 80 captures hardly soluble substances contained in the water flowing through the boiling piping 50. In the first embodiment, the scale catcher 80 is arranged at the same height position P2 in the height direction D1 as the heat exchanger 60 and the pump 40. More specifically, the scale catcher 80 is arranged so that it at least partially overlaps the heat exchanger 60 and the pump 40 in a parallel direction perpendicular to the height direction D1. Furthermore, the scale catcher 80 is arranged so that its position P2 in the height direction D1 is higher than the position P1 of the upper end of the tank 10. More specifically, the lower end of the scale catcher 80 is arranged so that it is higher in the height direction D1 than the position P1 of the upper end of the tank 10. This scale catcher 80 is arranged in a position where water flows in the order of the heat exchanger 60, the scale catcher 80, and the pump 40.

[0034] Similarly to the heat exchanger 60, the pump 40, and the scale catcher 80, the pressure relief valve 54 and the drain plug provided in the boiling piping 50 are also positioned in a height direction D1 higher than the position P1 of the upper end of the tank 10. The pressure relief valve 54 and the drain plug are also positioned so that they at least partially overlap the heat exchanger 60, the pump 40, and the scale catcher 80 in a parallel direction perpendicular to the height direction D1.

[0035] The tank 10 is also provided with a drain valve 81 and an auxiliary heat source 82 .

[0036] The drain valve 81 is used to open and close to drain the hot water from the tank 10. The drain valve 81 is connected to the drain valve inlet / outlet 10e.

[0037] The auxiliary heat source 82 supplementarily heats the hot water stored in the tank 10.

[0038] The storage type hot water heater 1 configured as described above operates in various operation modes including a boiling operation, a hot water supply operation, and a simultaneous operation of the boiling operation and the hot water supply operation.

[0039] When performing the boiling operation, as shown in Fig. 3, the pump 40 sucks up water from the tank 10 and causes the water to flow back into the second water supply pipe 30-2. The water from the tank 10 flows through the second water supply pipe 30-2 and the branching section 70 and into the boiling pipe 50. The water flowing through the boiling pipe 50 is sent to the heat exchanger 60.

[0040] Furthermore, the three-way valve 95 of the heating circuit 90 is switched to a direction in which the fluid sent from the heat exchanger 93 and heated by the auxiliary heat source 94 is sent to the heat exchanger 60. A circulation pipe 90a and a heater supply pipe 90b are connected to this three-way valve 95. The fluid flows through the circulation pipe 90a and is sent to the heat exchanger 60.

[0041] The heat exchanger 60 exchanges heat between the water flowing through the boiling pipe 50 and the fluid flowing through the circulation pipe 90a.

[0042] The water heated by the heat exchanger 60 has the hardly soluble substances trapped by the scale trap 80, and the hardly soluble substances are removed from the water.

[0043] The water from which the hardly soluble substances have been removed further flows through the boiling pipe 50. The heated water passes through the pump 40 and the upper inlet / outlet 10b of the tank 10, and is returned to the tank 10 from the opening 52a of the boiling pipe 50. This maintains the temperature of the hot water stored in the tank 10.

[0044] When performing hot water supply operation, as shown in FIG. 4, the hot water tap provided on the hot water supply pipe 20 is opened, and hot water is drawn up from the tank 10 and flows into the hot water supply pipe 20. At this time, when the hot water tap provided on the hot water supply pipe 20 is opened, water from the outside is naturally supplied via the first water supply pipe 30-1 and the second water supply pipe 30-2. The hot water flowing through the hot water supply pipe 20 is supplied to external equipment. A user performing hot water supply operation receives the required amount of hot water by, for example, operating the hot water tap. The external equipment is, for example, a hot water supply device installed in the bathtub, kitchen, or bathroom. Note that when the hot water tap provided on the hot water supply pipe 20 is closed, the supply of water from the outside also naturally stops. As a result, the supply of water via the first water supply pipe 30-1 and the second water supply pipe 30-2 also stops.

[0045] The operation of the boiling operation and hot water supply operation of the storage type water heater 1 has been described above, but as shown in Fig. 5, the storage type water heater 1 can also perform the boiling operation and the hot water supply operation simultaneously. In this case, water supplied from the first water supply pipe 30-1 can be supplied to the boiling pipe 50 via the branch section 70 by the suction force of the pump 40.

[0046] As described above, in the storage type water heater 1 according to the first embodiment, as shown in Fig. 2, the second water supply pipe 30-2 is used as a pipe for supplying water from the outside to the tank 10. During the boiling operation, the second water supply pipe 30-2 is used as part of a pipe for drawing water from the tank 10, heating the water, and then returning the water to the tank 10. This allows the number of parts to be reduced in the storage type water heater 1.

[0047] For example, as shown in Fig. 6, in the storage type hot water heater 1A according to Comparative Example 1, both the water supply pipe 30-3 and the boiling pipe 50 are connected to the lower part of the tank 10. In this case, the lower part of the tank 10 requires lower inlets 10c and 10d, which are connection parts for connecting the water supply pipe 30-3 and the boiling pipe 50. In addition, connection joints are required for connecting to the lower inlets 10c and 10d. This increases the number of parts.

[0048] In contrast to this, in the present embodiment 1, as shown in FIG. 2, the second water supply pipe 30-2 is used as a pipe for supplying water to the tank 10, and is also used as a pipe for use during boiling operation. Therefore, a connection port for connecting both the water supply pipe 30-3 and the boiling pipe 50 is not required at the bottom of the tank 10. This allows the number of parts to be reduced in the storage type water heater 1. Furthermore, the number of assembly steps when manufacturing the storage type water heater 1 can be reduced. As a result, the cost of manufacturing the storage type water heater 1 can be reduced.

[0049] Furthermore, in the present embodiment 1, the heat exchanger 60, the pump 40, and the scale catcher 80 are arranged such that the position P2 in the height direction D1 is higher than the position P1 of the upper end of the tank 10. Therefore, even if the temperature around the hot water storage type water heater 1 drops, the heat exchanger 60, the pump 40, and the scale catcher 80 can be prevented from freezing.

[0050] For example, as shown in FIG. 7 , in the storage type hot water heater 1B according to Comparative Example 2, the heat exchanger 60, the pump 40, and the scale catcher 80 are disposed at a height close to the bottom of the tank 10. For example, in winter, when the temperature around the storage type hot water heater 1 drops, the heat exchanger 60, the pump 40, and the scale catcher 80 may freeze. In this case, an external anti-freeze heater may be separately installed to prevent freezing. However, this increases the number of parts. Another method is to circulate hot water through the heating pipe 50 even when the heating operation is not in progress. However, this requires power for circulation, and the power consumption required for the operation of the storage type hot water heater 1B increases. Furthermore, since the heating operation must be performed even when it is not actually required, the efficiency of the operation of the storage type hot water heater 1B decreases.

[0051] In contrast, in the first embodiment, as shown in FIG. 2, the heat exchanger 60, the pump 40, and the scale catcher 80 are arranged such that a position P2 in the height direction D1 is higher than a position P1 at the upper end of the tank 10. Therefore, compared to the second comparative example, even if the ambient temperature around the hot water storage type water heater 1 drops, the heat exchanger 60, the pump 40, and the scale catcher 80 can be prevented from freezing. Furthermore, the warm air and heat radiation generated by the hot water stored in the tank 10 can prevent the heat exchanger 60, the pump 40, and the scale catcher 80 from freezing. Therefore, there is no need to separately install an external anti-freeze heater or circulate hot water through the boiling piping 50 even when the boiling operation is not in progress. As a result, the cost of manufacturing the hot water storage type water heater 1 can be reduced.

[0052] 1 and 2, in the first embodiment, opening 52a of boiling pipe 50 on the tank 10 side is positioned so as to protrude into the interior of tank 10. As a result, boiling pipe 50 is formed to include internal pipe 55, a portion of which is positioned inside tank 10. Therefore, hot water from boiling pipe 50 can be supplied to a desired position inside tank 10.

[0053] In the first embodiment, the hot water supply pipe 20 is formed so as to include an internal pipe 25, a part of which is disposed inside the tank 10. Therefore, hot water at a desired position inside the tank 10 can be supplied to the outside via the hot water supply pipe 20.

[0054] In the first embodiment, the second water supply pipe 30-2 is formed so as to include an internal pipe 35, a portion of which is disposed inside the tank 10. Therefore, water from the second water supply pipe 30-2 can be supplied to a desired position inside the tank 10, for example, the bottom of the tank 10.

[0055] In the first embodiment, the branching portion 70 has a first connection port 71, a second connection port 72, and a third connection port 73 that are open in three directions. The opening direction of the first connection port 71 and the opening direction of the second connection port 72 are arranged on the same axis. The first connection port 71 is connected to the first water supply pipe 30-1, and the second connection port 72 is connected to the second water supply pipe 30-2. This allows water to flow smoothly from the first water supply pipe 30-1 to the second water supply pipe 30-2.

[0056] Furthermore, in this embodiment 1, the scale catcher 80 is arranged at the same height position P2 in the height direction D1 as the heat exchanger 60 and the pump 40. More specifically, the scale catcher 80 is arranged so that it overlaps at least partially with the heat exchanger 60 and the pump 40 in a parallel direction perpendicular to the height direction D1. This allows the storage type water heater 1 to have a reduced length in the height direction D1. As a result, the storage type water heater 1 can be made smaller in the height direction D1 and lighter in weight. Also, the piping can be made shorter.

[0057] In addition, in the present embodiment 1, the branch section 70 is formed from a three-way joint, and the first water supply pipe 30-1, the second water supply pipe 30-2, and the boiling pipe 50 are formed as separate pipes. Therefore, compared to when each pipe is integrated, it is possible to improve the handling of parts, assembly efficiency, and maintainability for the user of the hot water storage type water heater 1.

[0058] Furthermore, in the first embodiment, the heat exchanger 60, the scale catcher 80, and the pump 40 are arranged in positions where the hot water flows in that order. This makes it possible to prevent malfunctions of the pump 40 due to the inclusion of foreign matter. In particular, sparingly soluble substances such as scale that tend to form in the heat exchanger 60 can be removed before flowing into the pump 40.

[0059] In the first embodiment, the other end 52 of the boiling pipe 50 is connected to the upper inlet / outlet 10b formed on the curved surface of the tank upper portion 12. Therefore, the other end 52 of the boiling pipe 50 is disposed in a position close to the end of the hot water supply pipe 20. This allows high-temperature hot water to be supplied to the outside by the hot water supply pipe 20 while reducing piping heat radiation loss.

[0060] Embodiment 2 In the storage type water heater 1 according to the first embodiment, as shown in Figures 1 and 2, the drain valve 81 is provided in the tank 10. However, this is not limited to this. As in the storage type water heater 2 according to the second embodiment shown in Figure 8, the drain valve 81 may be provided in the second water supply pipe 30-2. In this storage type water heater 2, as in the storage type water heater 1, the branch section 70 is arranged at a position lower than the heat exchanger 60 and at a position higher than the lowest part of the tank 10.

[0061] As described above, in the second embodiment, the tank 10 does not need to have a drain valve inlet / outlet 10e for connecting the drain valve 81. This allows the number of parts to be reduced in the storage type water heater 2. It also reduces the number of assembly steps when manufacturing the storage type water heater 2. As a result, the cost of manufacturing the storage type water heater 2 can be reduced.

[0062] Embodiment 3 In the storage type water heater 2 according to the second embodiment, as shown in Fig. 8, the branching section 70 is arranged such that its position P3 in the height direction D1 is lower than the position P2 of the heat exchanger 60 and higher than the position P4 of the lower end of the tank 10. The branching section 70 is also arranged lower than the position P5 of the joint that connects the tank body 11 and the lower tank part 13 of the tank 10. However, this is not limited to this. As in the storage type water heater 3 according to the third embodiment shown in Fig. 9, the position P3 in the height direction D1 of the branching section 70 may be arranged higher than the position P5 of the joint that connects the tank body 11 and the lower tank part 13 of the tank 10.

[0063] In this case, for example, the branch section 70 can be directly connected to the tank 10. This allows the second water supply pipe 30-2 to be omitted. Consequently, the number of parts in the storage type water heater 3 can be reduced. Furthermore, the number of assembly steps when manufacturing the storage type water heater 3 can be reduced. As a result, the cost of manufacturing the storage type water heater 3 can be reduced.

[0064] Embodiment 4 In the storage type water heater 3 according to the third embodiment, as shown in Fig. 9, the branching section 70 is arranged such that its position P3 in the height direction D1 is higher than the position P5 of the joint between the tank body 11 and the tank lower part 13 of the tank 10. However, this is not limited to this. As in the storage type water heater 4 according to the fourth embodiment shown in Fig. 10, the branching section 70 may be arranged such that its position P3 in the height direction D1 is higher than the position P6 of the center part of the tank body 11 in the height direction D1.

[0065] Even in this case, the temperature of the hot water inside the tank 10 at the central position P6 is often higher than the temperature of the hot water closer to the bottom, so the boiling piping 50 can be prevented from freezing more effectively than in embodiment 3.

[0066] Embodiment 5 In the storage type water heater 4 according to the fourth embodiment, as shown in Fig. 10, the branching section 70 is arranged such that its position P3 in the height direction D1 is higher than the position P6 of the center of the tank body 11 in the height direction D1. However, this is not limited to this. As in the storage type water heater 5 according to the fifth embodiment shown in Fig. 11, the branching section 70 may be arranged such that its position P3 in the height direction D1 is higher than the position P7 of the joint that is the connection between the tank body 11 and the tank upper part 12 of the tank 10.

[0067] In this case, the branching section 70 is positioned higher than the lowest part of the tank 10, so the overall length of the boiling piping 50 downstream of the branching section 70 can be shortened. In addition, the boiling piping 50 can be prevented from freezing due to the warm air and heat radiation generated by the hot water stored in the tank 10. Therefore, there is no need to separately install an external anti-freeze heater or circulate hot water through the boiling piping 50 even when the boiling operation is not in progress. As a result, the cost of manufacturing the storage type water heater 5 can be reduced.

[0068] Although the present embodiment has been described above, the present disclosure is not limited to the above embodiment.

[0069] For example, in this embodiment, the storage type water heaters 1 to 5 are each equipped with a scale catcher 80, as shown in Figures 1 and 2. However, this is not limited to this. The storage type water heaters 1 to 5 do not have to be equipped with the scale catcher 80. However, from the perspective of preventing malfunctions of the pump 40 due to the intrusion of foreign matter, it is preferable that the storage type water heaters 1 to 5 be equipped with the scale catcher 80.

[0070] In addition, in this embodiment, the heat exchanger 60, the pump 40, and the scale catcher 80 are disposed at a higher position than the tank 10. However, this is not limited to this. It is sufficient that at least the heat exchanger 60 and the pump 40 out of the heat exchanger 60, the pump 40, and the scale catcher 80 are disposed at a higher position than the tank 10.

[0071] In this embodiment, the branching portion 70 is a T-shaped three-way joint. However, this is not limited to this. The branching portion 70 may be a three-way valve that can be opened and closed. However, from the perspective of simplifying the structure of the hot water storage type water heaters 1 to 5, it is preferable that the branching portion 70 be a three-way joint.

[0072] Furthermore, in this embodiment, the heat exchanger 60 and the pump 40 are arranged at the same height position P2 in the height direction D1. However, this is not limited to this. The heat exchanger 60 and the pump 40 may be arranged at different height positions in the height direction D1. However, from the perspective of reducing the height direction D1 of the storage type hot water heaters 1 to 5, it is preferable that the heat exchanger 60 and the pump 40 are arranged at the same height position P2 in the height direction D1.

[0073] Furthermore, in this embodiment, the scale catcher 80 is disposed at the same height position P2 relative to the heat exchanger 60 and the pump 40. However, this is not limited to this. The scale catcher 80 may be disposed at a different height position relative to the heat exchanger 60 and the pump 40. However, from the viewpoint of reducing the height direction D1 of the storage type water heaters 1 to 5, it is preferable that the scale catcher 80 be disposed at the same height position P2 relative to the heat exchanger 60 and the pump 40.

[0074] In this embodiment, as shown in FIG. 2, the opening direction of the first connection port 71 of the branching portion 70 and the opening direction of the second connection port 72 are arranged on the same axis. The first connection port 71 is connected to the first water supply pipe 30-1, and the second connection port 72 is connected to the second water supply pipe 30-2. However, this is not limited to this. As in a hot water storage type water heater 6 according to embodiment 6 shown in FIG. 12, the first connection port 71 may be connected to the second water supply pipe 30-2, and the second connection port 72 may be connected to the boiling pipe 50. As a result, the opening direction of the first connection port 71 of the branching portion 70 and the opening direction of the second connection port 72 are arranged on the same axis. In embodiment 6, the first connection port 71 is connected to the first water supply pipe 30-1, and the third connection port 73 is connected to the first water supply pipe 30-2. The third connection port 73, to which the first water supply pipe 30-1 is connected, opens within a range θ of 0° to 180° with respect to a horizontal plane perpendicular to the height direction of the storage-type water heater. That is, the outward normal to the opening surface faces above the horizontal. Therefore, the range θ is within the range of elevation angles, and the third connection port 73 opens within the range of elevation angles with respect to the parallel plane S2. Furthermore, the opening direction of the first connection port 71 of the branching portion 70 and the opening direction of the second connection port 72 are arranged on the same axis. Furthermore, in the sixth embodiment, the branching portion 70 may be directly connected to the tank 10, and the second water supply pipe 30-2 may be omitted.

[0075] 1 shows an example in which the first connection port 71 to which the first water supply pipe 30-1 is connected opens in a direction at an angle of 90° relative to the surface S2. However, this is not limited to this. The first connection port 71 to which the first water supply pipe 30-1 is connected may open within a range θ of 0° to 180° relative to the surface S2. For example, the first connection port 71 to which the first water supply pipe 30-1 is connected may open in a direction at an angle of 45° relative to the surface S2.

[0076] Various aspects of the present disclosure are described below. (Appendix 1) A tank for storing hot water, a hot water supply pipe for supplying the hot water from the tank to the outside; a first water supply pipe for supplying water to the tank from the outside; a second water supply pipe connected between the first water supply pipe and the tank and supplying the water from the first water supply pipe to the tank; a pump for sucking up the water from the tank to cause the water to flow back into the second water supply pipe; a boiling pipe connected to the second water supply pipe and the tank, for returning the water that has been sucked up by the pump and flowed through the second water supply pipe to the tank; a heat exchanger that performs heat exchange to heat the hot water flowing through the boiling pipe; A storage type water heater comprising a branch section that connects the first water supply pipe, the second water supply pipe, and the boiling pipe.

[0077] (Appendix 2) the heat exchanger and the pump are disposed at a position higher than the tank; A hot water storage type water heater as described in Appendix 1, wherein the branching portion is positioned lower than the heat exchanger and higher than the bottom of the tank.

[0078] (Appendix 3) a scale capture device that is installed in the boiling pipe and captures hardly soluble substances contained in the water flowing through the boiling pipe; A hot water storage type water heater as described in Appendix 1 or 2, wherein the scale capture device is positioned higher than the tank.

[0079] (Appendix 4) The opening of the boiling pipe on the tank side is disposed at a position protruding into the inside of the tank, A hot water storage type water heater described in any one of appendix 1 to 3, wherein the boiling piping includes an internal piping, a portion of which is arranged inside the tank.

[0080] (Appendix 5) The tank has a cylindrical tank body portion and a tank lower portion that covers a lower opening in a height direction of the tank body portion, A hot water storage type water heater according to any one of appendixes 1 to 4, wherein the branching portion is positioned higher than the connection portion between the tank body portion and the lower portion of the tank.

[0081] (Appendix 6) The tank has a cylindrical tank body, 6. The hot water storage type water heater according to any one of claims 1 to 5, wherein the branching portion is arranged at a position higher than the center in the height direction of the tank body portion.

[0082] (Appendix 7) The tank has a cylindrical tank body and a tank upper portion that covers an upper opening in a height direction of the tank body, A hot water storage type water heater according to any one of appendixes 1 to 6, wherein the branching portion is positioned higher than the connection portion between the upper portion of the tank and the tank body portion.

[0083] (Appendix 8) the branch portion has a first connection port, a second connection port, and a third connection port that are open in three directions, The opening direction of the first connection port and the opening direction of the second connection port are provided on the same axis, The first water supply pipe is connected to the first connection port, and the second water supply pipe is connected to the second connection port, A storage-type water heater described in any one of Appendices 1 to 7, wherein the first connection port to which the first water supply pipe is connected opens within a range of 0° to 180° with respect to a horizontal plane perpendicular to the height direction of the storage-type water heater, and the outward normal of the opening surface faces above the horizontal.

[0084] (Appendix 9) the branch portion has a first connection port, a second connection port, and a third connection port that are open on three sides, The opening direction of the first connection port and the opening direction of the second connection port are provided on the same axis, the second water supply pipe is connected to the first connection port, the boiling pipe is connected to the second connection port, and the first water supply pipe is connected to the third connection port; A storage-type water heater described in any one of Appendices 1 to 8, wherein the third connection port to which the first water supply pipe is connected opens within a range of 0° to 180° with respect to a horizontal plane perpendicular to the height direction of the storage-type water heater, and the outward normal of the opening surface faces above the horizontal.

[0085] (Appendix 10) A hot water storage type water heater described in any one of appendix 1 to 9, wherein the heat exchanger and the pump are arranged at the same height.

[0086] (Appendix 11) a scale capture device that is installed in the boiling pipe and captures hardly soluble substances contained in the water flowing through the boiling pipe; A storage type water heater as described in Appendix 10, wherein the scale capture device is arranged at the same height as the heat exchanger and the pump.

[0087] (Appendix 12) The branch portion is formed by a three-way joint, A hot water storage type water heater described in any one of appendixes 1 to 11, wherein the first water supply pipe, the second water supply pipe, and the boiling water pipe are formed as separate pipes.

[0088] (Appendix 13) a scale capture device that is installed in the boiling pipe and captures hardly soluble substances contained in the water flowing through the boiling pipe; A hot water storage type water heater described in any one of appendixes 1 to 12, wherein the heat exchanger, the scale capturer, and the pump are arranged in positions where the hot water flows in that order.

[0089] (Appendix 14) The tank has a cylindrical tank body and a tank upper portion that covers an upper opening in a height direction of the tank body, The upper portion of the tank has a curved surface that bulges upward, A hot water storage type water heater according to any one of appendixes 1 to 13, wherein the boiling pipe is connected to the curved surface at the top of the tank.

[0090] (Appendix 15) Equipped with circulating pipes through which water flows, The heat exchanger performs heat exchange between the water flowing through the boiling pipe and the fluid flowing through the circulation pipe, 15. The hot water storage type water heater according to any one of claims 1 to 14, wherein the fluid flowing through the circulation pipe is water.

[0091] The present disclosure allows various embodiments and modifications without departing from the broad spirit and scope of the present disclosure. Furthermore, the above-described embodiments are intended to illustrate the present disclosure and do not limit the scope of the present disclosure. That is, the scope of the present disclosure is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and the meaning of equivalent disclosures are considered to be within the scope of the present disclosure. [Explanation of symbols]

[0092] 1, 1A, 1B, 2, 3, 4, 5, 6: storage type water heater, 1a: housing, 10: tank, 10a, 10b: upper inlet / outlet, 10c, 10d: lower inlet / outlet, 10e: drain valve inlet / outlet, 11: tank body, 12: upper tank, 13: lower tank, 20: hot water supply pipe, 25: internal pipe, 30-1: first water supply pipe, 30-2: second water supply pipe, 30-2a, 30-2b: end, 30-3: water supply pipe, 35: internal pipe, 40: pump, 50: boiling pipe, 51, 52: end, 52a: opening, 54: pressure relief valve, 55 : Internal piping, 60: Heat exchanger, 70: Branching section, 71: First connection port, 72: Second connection port, 73: Third connection port, 80: Scale catcher, 81: Drain valve, 82: Auxiliary heat source, 90: Heating circuit, 90a: Circulation piping, 90b: Outlet piping for heater, 90c: Return piping for heater, 90d: Pipe for heat pump, 91: Pump, 92: Flow meter, 93: Heat exchanger, 94: Auxiliary heat source, 95: Three-way valve, 100: Control section, D1: Height direction, P1, P2, P3, P4, P5, P6, P7: Position, S: Installation surface, Surface: S2.

Claims

1. A tank for storing hot water, a hot water supply pipe for supplying the hot water from the tank to the outside; a first water supply pipe for supplying water to the tank from the outside; a second water supply pipe connected between the first water supply pipe and the tank and supplying the water from the first water supply pipe to the tank; a pump for sucking up the water from the tank to cause the water to flow back into the second water supply pipe; a boiling pipe connected to the second water supply pipe and the tank, for returning the water that has been sucked up by the pump and flowed through the second water supply pipe to the tank; a heat exchanger that performs heat exchange to heat the water flowing through the boiling pipe; A storage type water heater comprising: a branch portion connecting the first water supply pipe, the second water supply pipe, and the boiling pipe.

2. the heat exchanger and the pump are disposed at a position higher than the tank; The hot water storage type water heater according to claim 1 , wherein the branching portion is disposed at a position lower than the heat exchanger and higher than a lowermost portion of the tank.

3. a scale capture device that is installed in the boiling pipe and captures hardly soluble substances contained in the water flowing through the boiling pipe; The hot water storage type water heater according to claim 1 or 2, wherein the scale catcher is disposed at a position higher than the tank.

4. The opening of the boiling pipe on the tank side is disposed at a position protruding into the inside of the tank, The hot water storage type water heater according to claim 1 or 2, wherein the boiling pipe includes an internal pipe, a portion of which is disposed inside the tank.

5. The tank has a cylindrical tank body portion and a tank lower portion that covers a lower opening in a height direction of the tank body portion, The hot water storage type water heater according to claim 1 or 2, wherein the branch portion is disposed at a position higher than a connection portion between the tank body portion and the tank lower portion.

6. The tank has a cylindrical tank body, The hot water storage type water heater according to claim 1 or 2, wherein the branching portion is disposed at a position higher than a center in a height direction of the tank body portion.

7. The tank has a cylindrical tank body and a tank upper portion that covers an upper opening in a height direction of the tank body, The hot water storage type water heater according to claim 1 or 2, wherein the branch portion is disposed at a position higher than a connection portion between the tank upper portion and the tank body portion.

8. the branch portion has a first connection port, a second connection port, and a third connection port that are open in three directions, an opening direction of the first connection port and an opening direction of the second connection port are provided on the same axis; The first water supply pipe is connected to the first connection port, and the second water supply pipe is connected to the second connection port, A storage-type water heater as described in claim 1 or 2, wherein the first connection port to which the first water supply pipe is connected opens within a range of 0° to 180° with respect to a horizontal plane perpendicular to the height direction of the storage-type water heater, and the outward normal of the opening surface faces above the horizontal.

9. the branch portion has a first connection port, a second connection port, and a third connection port that are open in three directions, an opening direction of the first connection port and an opening direction of the second connection port are provided on the same axis; the second water supply pipe is connected to the first connection port, the boiling water pipe is connected to the second connection port, and the first water supply pipe is connected to the third connection port; A storage-type water heater as described in claim 1 or 2, wherein the third connection port to which the first water supply pipe is connected opens within a range of 0° to 180° with respect to a horizontal plane perpendicular to the height direction of the storage-type water heater, and the outward normal of the opening surface faces above the horizontal.

10. The hot water storage type water heater according to claim 1 or 2, wherein the heat exchanger and the pump are disposed at the same height.

11. a scale capture device that is installed in the boiling pipe and captures hardly soluble substances contained in the water flowing through the boiling pipe; The hot water storage type water heater according to claim 10, wherein the scale catcher is disposed at the same height as the heat exchanger and the pump.

12. The branch portion is formed by a three-way joint, The hot water storage type water heater according to claim 1 or 2, wherein the first water supply pipe, the second water supply pipe, and the boiling water pipe are formed as separate pipes.

13. a scale capture device that is installed in the boiling pipe and captures hardly soluble substances contained in the water flowing through the boiling pipe; The hot water storage type water heater according to claim 1 or 2, wherein the heat exchanger, the scale catcher, and the pump are arranged in positions where the hot water flows in that order.

14. The tank has a cylindrical tank body and a tank upper portion that covers an upper opening in a height direction of the tank body, The upper portion of the tank has a curved surface that bulges upward, The hot water storage type water heater according to claim 1 or 2, wherein the boiling pipe is connected to the curved surface of the upper part of the tank.

15. Equipped with circulation piping through which fluid flows, The heat exchanger performs heat exchange between the water flowing through the boiling pipe and the fluid flowing through the circulation pipe, The hot water storage type water heater according to claim 1 or 2, wherein the fluid flowing through the circulation pipe is water.

Images