Water heater

Abstract

To prevent a heating medium poured from a water pouring valve with a great force from hitting a partition wall of a cistern and leaking from a water supply port.SOLUTION: A hot water supply / heating machine 1 is the hot water supply / heating machine 1 which includes: a cistern 70 for storing a heating medium for heating; and a water pouring valve 100 for automatically supplying the heating medium to the cistern 70. The cistern 70 includes: a water supply port 80B for manually supplying the heating medium to the cistern 70; a water pouring port 80A on which the water pouring valve 100 is mounted; and a partition wall 90 positioned below the water pouring port 80A. The water pouring valve 100 includes: a valve body 101 which has a first flow passage P1 where the heating medium flows; and a discharge part 102 which has a second flow passage P2 continued to the lower part of the valve body 101 and communicated with the first flow passage P1. The discharge part 102 includes a discharge port 102A positioned at the lower end of the second flow passage P2, and for discharging the heating medium toward the cistern 70. On the internal wall of the second flow passage P2, an inclined surface 105 is formed which inclines so as to be further separated from the water supply port 80B as approaching closer to the discharge port 102A.SELECTED DRAWING: Figure 6

Description

Technical Field

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

Background Art

[0002] As a cistern used in a water heater, the cistern described in Japanese Patent Application Laid-Open No. 2019-174049 (hereinafter referred to as Patent Document 1) is known. This cistern has a housing, a first water level electrode, and a second water level electrode. The housing is provided with a water supply port, a discharge port, a return connection port, and an outgoing connection port. The water supply port, the discharge port, the return connection port, and the outgoing connection port communicate with the inside of the housing. Water that has circulated through the heating circuit returns into the housing from the return connection port, and water is sent out from the housing through the outgoing connection port so as to circulate through the heating circuit. A flow path is provided inside the housing. The flow path has one end and the other end. The flow path is connected to the return connection port at one end. The flow path has a flow path upper wall, a flow path bottom wall, a first flow path side wall, and a second flow path side wall. The first portion of the flow path upper wall faces the return connection port. Therefore, the water returning from the return connection port into the housing collides with the first portion of the flow path upper wall, and the flow velocity is reduced.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described cistern, there may be provided a replenishing port for manually replenishing water as a heat medium in the vicinity of the return connection port. In that case, the water returning from the return connection port into the housing hits the first portion of the upper wall of the flow path with great force, and there is a risk that water may leak from the replenishing port due to splashing. Usually, the replenishing port is plugged with a rubber stopper, but there is a possibility of forgetting to attach it during maintenance, and in that case, there is a risk that water may leak from the replenishing port to the outside of the cistern.

Means for Solving the Problem

[0005] The water heater of the present disclosure is a water heater including a cistern for storing a heat medium for heating and a water injection valve for automatically replenishing the heat medium to the cistern, wherein the cistern has a water supply port for manually replenishing the heat medium to the cistern, a water injection port to which the water injection valve is attached, and a partition wall located below the water injection port, the water injection valve has a valve body having a first flow path through which the heat medium flows, and a discharge portion having a second flow path connected to the lower side of the valve body and communicating with the first flow path, the discharge portion has a discharge port located at the lower end of the second flow path and discharging the heat medium toward the cistern, and an inclined surface is formed on the inner wall of the second flow path so as to be inclined away from the water supply port as it approaches the discharge port.

Effect of the Invention

[0006] According to the present disclosure, it is possible to prevent the heat medium injected forcefully from the water injection valve from hitting the partition wall of the cistern and leaking from the water supply port.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0008] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described. (1) The water heater of the present disclosure is a water heater including a cistern for storing a heat medium for heating and a water injection valve for automatically replenishing the heat medium into the cistern. The cistern has a water supply port for manually replenishing the heat medium into the cistern, a water injection port to which the water injection valve is attached, and a partition wall located below the water injection port. The water injection valve has a valve body having a first flow path through which the heat medium flows, and a discharge portion connected to the lower side of the valve body and having a second flow path communicating with the first flow path. The discharge portion has a discharge port located at the lower end of the second flow path and discharging the heat medium toward the cistern. On the inner wall of the second flow path, an inclined surface is formed so as to be away from the water supply port as it approaches the discharge port.

[0009] After the heat medium flows from the first flow path of the water injection valve into the second flow path of the discharge portion, it is discharged from the discharge port toward the partition wall while changing its direction by the inclined surface. At this time, by obliquely injecting the heat medium away from the water supply port with respect to the partition wall, it becomes easier to prevent the rebound when hitting the partition wall. Therefore, it is possible to prevent the heat medium vigorously poured from the water injection valve from hitting the partition wall of the cistern and leaking from the water supply port.

[0010] (2) In the water heater according to (1), the second flow path is formed in a tapered shape that changes from an oval cross-section to a circular cross-section as it goes from the first flow path side to the discharge port side, and a discharge port end surface having an R shape is formed on the inner wall of the second flow path on the discharge port side and on the side opposite to the inclined surface. Since the second flow path can be formed using a slide type that forms the first flow path, the structure of the mold does not have to be complicated. The tapered shape of the second flow path makes it easier for turbulent flow to occur, and by further providing an R shape on the end face of the discharge port, it is possible to further shallow the incident angle of the heat medium by the Coandă effect.

[0011] [Details of Embodiments of the Present Disclosure] Embodiments of the present disclosure will be described with reference to FIGS. 1 to 7. The present disclosure is not limited to these examples, but is indicated by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0012] [Overall Structure of the Water Heater and Heater] FIG. 1 is a schematic circuit diagram of a water heater and heater 1 (an example of a water heater). The water heater and heater 1 has a hot water supply circuit A, a heating circuit B, and a bath circuit C. The cistern 70 according to the present embodiment is provided in the heating circuit B.

[0013] The water heater and heater 1 has a hot water supply combustion chamber 4 and a heating combustion chamber 5 partitioned by a partition member 3, and a burner 6, inside an inner cylinder 2 housed in a case (not shown). The burner 6 includes a hot water supply burner 6A disposed at the lower part of the hot water supply combustion chamber 4 and a heating burner 6B disposed at the lower part of the heating combustion chamber 5. Further, an ignition plug 8 and a flame rod 9 are respectively provided in each combustion chamber 4, 5. A combustion fan 10 for supplying combustion air to each burner 6A, 6B is provided at the lower part of the inner cylinder 2.

[0014] In the upper part of the hot water supply combustion chamber 4, a hot water supply primary heat exchanger 11 and a hot water supply secondary heat exchanger 12 through which the combustion exhaust of the hot water supply burner 6A passes are provided. In the upper part of the heating combustion chamber 5, a heating primary heat exchanger 13 and a heating secondary heat exchanger 14 through which the combustion exhaust of the heating burner 6B passes are provided. Each secondary heat exchanger 12, 14 is housed in an exhaust hood 15 provided at the upper part of the inner cylinder 2. An exhaust port 16 for discharging the combustion exhaust that has passed through each secondary heat exchanger 12, 14 is formed in the exhaust hood 15.

[0015] A gas pipe 17 to which an external gas pipe is connected is connected to a gas inlet provided on the bottom surface of the case. Gas branch pipes 18, 18... branched from the gas pipe 17 are respectively connected to each of the hot water supply burners 6A and the heating burner 6B, and a gas solenoid valve 19 for opening and closing a gas flow path is provided in each gas branch pipe 18. Further, an original gas solenoid valve 20 and a gas proportional valve 21 are respectively provided in the gas pipe 17 before branching.

[0016] A water supply pipe 22 connected to a water inlet on the bottom surface of the case is connected to the inlet of the heat absorption pipe of the hot water supply secondary heat exchanger 12. In the water supply pipe 22, a strainer 23 having a drain plug, a hot water supply water volume sensor 24 for detecting the amount of water flowing through the water supply pipe 22, a hot water supply inlet thermistor 25 for detecting the inlet water temperature, and a water volume control valve 26 for controlling the amount of water flowing through the water supply pipe 22 are provided from the upstream side. The outlet of the heat absorption pipe is connected to the inlet of the heat transfer pipe of the hot water supply primary heat exchanger 11, and a hot water outlet pipe 27 connected to a hot water outlet on the bottom surface of the case is connected to the outlet of the heat transfer pipe. In the hot water outlet pipe 27, a hot water supply heat exchanger thermistor 28 for detecting the outlet temperature from the hot water supply primary heat exchanger 11 and a hot water supply outlet thermistor 29 for detecting the hot water outlet temperature from the appliance on the downstream side of the hot water supply heat exchanger thermistor 28 are provided. A bypass pipe 30 that bypasses the hot water supply primary and secondary heat exchangers 11 and 12 is connected between the upstream side of the hot water supply outlet thermistor 29 in the hot water outlet pipe 27 and the downstream side of the water volume control valve 26 in the water supply pipe 22, and a water distribution valve 31 for controlling the bypass flow rate is provided in the bypass pipe 30.

[0017] In this way, a hot water supply circuit A is formed in the case in which water from the water supply pipe 22 passes through the hot water supply secondary heat exchanger 12 and the hot water supply primary heat exchanger 11 in this order, exchanges heat with the combustion exhaust gas of the hot water supply burner 6A and is heated, and then hot water is discharged from the hot water outlet pipe 27.

[0018] On one side, a heating return pipe 32 connected to the heating return port on the bottom surface of the case is connected to the inlet of the heat absorption pipe of the heating secondary heat exchanger 14. The heating return port is connected to the downstream ends of the pipes extending from the high-temperature radiator 33 and the low-temperature radiator 34 outside the hot water heating machine 1. The high-temperature radiator 33 is, for example, a heating blower that blows warm air into the room. The low-temperature radiator 34 is, for example, floor heating. The outlet of the heat absorption pipe of the heating secondary heat exchanger 14 is connected to an intermediate pipe 35. An expansion tank 70 and a heating circulation pump 36 are provided in the intermediate pipe 35. The expansion tank 70 is for preventing the pipes and the like constituting the heating circuit B from being damaged when the heat medium (water in this embodiment) circulating in the heating circuit B is heated and expands. The detailed configuration of the expansion tank 70 will be described later. A heating low-temperature thermistor 37 is provided in the expansion tank 70. The downstream end of the intermediate pipe 35 is connected to the inlet of the heat transfer pipe of the heating low-temperature forward pipe 38 and the heating primary heat exchanger 13. The heating low-temperature forward pipe 38 is connected to the low-temperature radiator 34 via a built-in thermostatic valve 39. The outlet of the heat transfer pipe of the heating primary heat exchanger 13 is connected to a heating high-temperature forward pipe 40. The heating high-temperature forward pipe 40 is connected to the high-temperature radiator 33. A heating high-temperature thermistor 41 is provided in the heating high-temperature forward pipe 40. The heating high-temperature forward pipe 40 and the heating return pipe 32 are connected by a bath heating pipe 42. A supplementary heating flow control valve 43 is provided in the bath heating pipe 42. A heating bypass pipe 44 that bypasses the heating primary and heating secondary heat exchangers 13 and 14 is connected between the upstream side of the expansion tank 70 in the intermediate pipe 35 and the heating high-temperature forward pipe 40, and a bypass thermostatic valve 45 for controlling the bypass flow rate is provided in the heating bypass pipe 44.

[0019] Therefore, in the heating circuit B, the heat medium heated by the heating secondary heat exchanger 14 circulates to the heating return pipe 32 through the intermediate pipe 35, the expansion tank 70, the heating low-temperature forward pipe 38, and the low-temperature radiator 34, and flows into the heating primary heat exchanger 13 through the intermediate pipe 35 and the expansion tank 70. The heat medium heated by the heating primary heat exchanger 13 returns to the heating return pipe 32 through the heating high-temperature forward pipe 40 and the high-temperature radiator 33, and circulates to the heating primary heat exchanger 13 through the heating secondary heat exchanger 14, the intermediate pipe 35, and the expansion tank 70.

[0020] The bathtub circuit C is provided with a bathtub heat exchanger 46 into which a bathtub heating pipe 42 is inserted. The inlet of the bathtub heat exchanger 46 is connected to a bathtub return pipe 47 connected to the bathtub return port on the bottom surface of the case. The bathtub return port is connected to the bathtub 49 via an external bathtub return pipe 48. A bathtub circulation pump 50 is provided on the downstream side of the bathtub return pipe 47. A bathtub return thermistor 51 for detecting the bathtub return temperature is provided on the upstream side of the bathtub circulation pump 50. A water flow switch 52 and a water level sensor 53 are provided on the downstream side of the bathtub circulation pump 50. The outlet of the bathtub heat exchanger 46 is connected to a bathtub supply pipe 54 connected to the bathtub supply port on the bottom surface of the case. The bathtub supply port is connected to the bathtub 49 via an external bathtub supply pipe 55. A bathtub supply thermistor 56 for detecting the bathtub supply temperature is provided on the bathtub supply pipe 54.

[0021] Also, a drop pipe 57 is connected between the downstream side of the bypass pipe 30 in the hot water supply pipe 27 and the upstream side of the bathtub circulation pump 50 in the bathtub return pipe 47. The drop pipe 57 is provided with a drop water solenoid valve 58 for opening and closing the drop pipe 57 and a bathtub water volume sensor 59 for detecting the amount of water flowing through the drop pipe 57, respectively, from the upstream side (hot water supply pipe 27 side). The drop pipe 57 enables the hot water heated in the hot water supply circuit A to be supplied to the bathtub 49. Three check valves 60, 60, 60 are provided on the downstream side of the bathtub water volume sensor 59. An edge cut-off valve 61 is connected between these check valves 60. The edge cut-off valve 61 is connected to a drain pipe 62 connected to an overflow discharge port provided on the bottom surface of the case and an introduction pipe 63 connected to the downstream side of the strainer 23 in the water supply pipe 22. When the internal pressure of the hot water in the drop pipe 57 increases due to the back pressure from the bathtub return pipe 47 and becomes greater than the back pressure from the introduction pipe 63, the edge cut-off valve 61 discharges the hot water flowing back from the drop pipe 57 to the overflow discharge port via the drain pipe 62.

[0022] In this way, a bath circuit C for circulating the hot and cold water in the bathtub 49 is formed by the bath heat exchanger 46, the bath supply pipe 54, the bath return pipe 47, and the like.

[0023] Inside the case, a neutralizer 64 for neutralizing the drain generated in the hot water supply secondary heat exchanger 12 and the heating secondary heat exchanger 14 is provided. The neutralizer 64 is connected to a drain receiver 66 provided on the bottom surface of the exhaust hood 15 via a drain introduction pipe 65, and is also connected to the drain pipe 62 of the edge cut valve 61 via a drain discharge pipe 67. The neutralizer 64 is provided with a water level electrode 68 for detecting the water level.

[0024] Although not shown, the hot water supply and heating unit 1 includes a controller that performs hot water temperature control, hot water filling control for the bathtub 49, temperature control related to heating, etc. to operate each valve and the like in response to detection signals from each thermistor, sensor, etc., and a remote control that is communicably connected to the controller.

[0025] [Cistern] Hereinafter, with reference to FIGS. 2 to 7, the configuration of the cistern 70 of the present embodiment will be described in detail. As shown in FIG. 2, the cistern 70 includes a housing 71 and a liquid level electrode 72 for detecting the liquid level (water level) of the heat medium inside the housing 71.

[0026] [Housing] As shown in FIG. 3, the housing 71 includes a box-shaped housing main body 71A and a lid body 71B attached to the right side of the housing main body 71A. The lid body 71B constitutes the right side wall portion of the housing 71. As shown in FIG. 4, the housing main body 71A includes an upper wall 74, a bottom wall 75 disposed below the upper wall 74, a front wall 76 connecting the front edge of the upper wall 74 and the front edge of the bottom wall 75, a rear wall 77 connecting the rear edge of the upper wall 74 and the rear end piece of the bottom wall 75, and a left wall 78 connecting the left edge of the upper wall 74 and the left edge of the bottom wall 75. The housing main body 71A includes a partition wall 90, a guide wall portion 91, a partition wall 85, an inclined wall 86, an intermediate wall 87, and a forward port side partition wall 95 inside thereof.

[0027] [Return port, forward port] As shown in FIG. 4, a return port 75A and an outlet port 75B that penetrate the bottom wall 75 of the housing 71 in the vertical direction are formed in the bottom wall 75. The return port 75A is arranged in the rear portion of the bottom wall 75, and the outlet port 75B is arranged in the front portion of the bottom wall 75. The return port 75A is an opening through which the heat medium is introduced into the housing 71. The outlet port 75B is an opening through which the heat medium is sent out from the housing 71 to the outside. In the heating circuit B, as shown in FIG. 1, the return port 75A is connected to the upstream side (secondary heat exchanger 14 side) of the intermediate pipe 35. The outlet port 75B is connected to the downstream side (heating low-temperature forward pipe 38 side) of the intermediate pipe 35.

[0028] [Liquid level electrode] As shown in FIG. 4, the liquid level electrode 72 includes a first liquid level electrode 72A and a second liquid level electrode 72B. The first liquid level electrode 72A and the second liquid level electrode 72B are formed in a rod shape. The first liquid level electrode 72A is provided longer in the vertical direction than the second liquid level electrode 72B. The first liquid level electrode 72A and the second liquid level electrode 72B are fixed to the housing 71 in a state of penetrating the upper wall 74 of the housing 71. Specifically, the first liquid level electrode 72A and the second liquid level electrode 72B are respectively inserted into a first through hole 79A and a second through hole 79B formed by penetrating the upper wall 74 of the housing 71 in the vertical direction. The first liquid level electrode 72A and the second liquid level electrode 72B are arranged in the rear portion of the upper wall 74. The first liquid level electrode 72A is arranged more rearward than the second liquid level electrode 72B.

[0029] The first liquid level electrode 72A and the second liquid level electrode 72B are fixed to the housing 71 with their upper ends at the same height. The lower end of the first liquid level electrode 72A is arranged below the lower end of the second liquid level electrode 72B. The height of the lower end of the first liquid level electrode 72A is set as the lowest liquid level L1, and the height of the lower end of the second liquid level electrode 72B is set as the highest liquid level L2. The first liquid level electrode 72A and the second liquid level electrode 72B are connected to a controller, and the controller can detect the on state when the first liquid level electrode 72A and the second liquid level electrode 72B come into contact with the heat medium respectively, and detect the off state in other cases. Thereby, when the water heater 1 is in operation, the liquid level of the heat medium in the housing 71 is controlled to be at a height position between the lowest liquid level L1 and the highest liquid level L2. For example, when the first liquid level electrode 72A is in the off state, the controller determines that the liquid level has not reached the lowest liquid level L1, and the heat medium is filled from the filling port 80 described below. Also, when the second liquid level electrode 72B is in the on state, the controller determines that the liquid level has reached the highest liquid level L2, and the heat medium from the filling port 80 is stopped.

[0030] [Filling port] The upper wall 74 of the housing 71 includes a first upper wall 74A arranged above the bottom wall 75, and a second upper wall 74B extending obliquely downward forward from the front edge of the first upper wall 74A. In this embodiment, two filling ports 80 are provided, one is a water injection port 80A and the other is a water supply port 80B. The water injection port 80A is formed through the first upper wall 74A. The water supply port 80B is formed through the second upper wall 74B. The water injection port 80A and the water supply port 80B are arranged at the front side portion of the upper wall 74. As shown in FIG. 1, the water injection port 80A is connected to the downstream side of the strainer 23 in the water supply pipe 22 via a makeup water solenoid valve 81 and a makeup water pipe 82. Thereby, in the water heater 1, the heat medium can be automatically filled into the housing 71 by the controller. Note that the water supply port 80B is used for an operator to manually fill the heat medium into the housing 71.

[0031] [Overflow port] As shown in FIG. 4, the front wall 76 of the housing 71 includes a first front wall 76A extending upward from the front edge of the bottom wall 75, a second front wall 76B extending forward from the upper edge of the first front wall 76A, and a third front wall 76C extending upward from the front edge of the second front wall 76B and connected to the second upper wall 74B. An overflow port 83 is formed in the front wall 76 so as to penetrate the second front wall 76B in the vertical direction. When the heat medium in the housing 71 exceeds a predetermined liquid level, the overflow port 83 allows the heat medium to overflow to the outside of the housing 71, thereby preventing damage to the housing 71. In the present embodiment, when the liquid level of the heat medium in the housing 71 exceeds the height position of the second front wall 76B, the heat medium is discharged from the overflow port 83 to the outside of the housing 71. As shown in FIG. 1, in the hot water heating apparatus 1, the overflow port 83 is connected to an overflow discharge port provided on the bottom surface of the case via an overflow pipe 84.

[0032] [Partition wall] The filling port 80 and the overflow port 83 are arranged at positions that almost overlap in the vertical direction. Therefore, in the present embodiment, a partition wall 90 is provided to prevent the heat medium filled from the filling port 80 from being directly discharged from the overflow port 83 to the outside of the housing 71. The partition wall 90 is provided below the filling port 80 and above the overflow port 83. The partition wall 90 extends from the front wall 76 and the left wall 78 and is disposed on the front side of the housing 71. The partition wall 90 includes a first partition wall 90A extending rearward while inclining slightly obliquely downward from the upper part of the third front wall 76C, a second partition wall 90B extending rearward while inclining obliquely downward from the rear edge of the first partition wall 90A, and a third partition wall 90C extending downward from the lower edge of the second partition wall 90B. The first partition wall 90A is disposed directly above the second front wall 76B.

[0033] [Guide wall portion, inclined portion] As shown in FIG. 4, the housing 71 of the present embodiment includes a guide wall portion 91 disposed between the filling port 80 and the liquid level electrode 72. The guide wall portion 91 extends generally in the vertical direction. More specifically, the guide wall portion 91 includes a first guide wall portion 91A extending in the vertical direction, and an inclined portion 91B that extends in the front obliquely upward direction while curving from the upper end edge of the first guide wall portion 91A. The upper end portion of the guide wall portion 91 is disposed above the partition wall 90.

[0034] By providing the guide wall portion 91, when the heat medium filled from the filling port 80 hits the partition wall 90 and tries to jump toward the liquid level electrode 72 side, the heat medium can be guided downward. Therefore, it is possible to prevent the heat medium filled from the filling port 80 from hitting the liquid level electrode 72. Further, by providing the inclined portion 91B, while reducing the momentum of the heat medium that hits the partition wall 90 and bounces back toward the liquid level electrode 72 side by the guide wall portion 91, it becomes easier to further guide the heat medium downward.

[0035] [Partition wall] As shown in FIG. 4, in the housing 71, the liquid level electrode 72 is disposed above the return port 75A, and a partition wall 85 is formed at a position between the liquid level electrode 72 and the return port 75A. Specifically, the partition wall 85 partitions a first space S1 in which the liquid level electrode 72 is disposed and a second space S2 provided in the vicinity of the return port 75A. The second space S2 is disposed at the rear and lower part in the housing 71. The first space S1 is disposed above the second space S2 in the housing 71 and behind an intermediate wall 87, which will be described later.

[0036] The partition wall 85 includes a first partition wall 85A, a second partition wall 85B, and a third partition wall 85C. The first partition wall 85A extends from the rear wall 77 and the left wall 78 and has a flat plate shape in the vertical direction. The second partition wall 85B extends from the left wall 78 and has a flat plate shape in the vertical direction. The second partition wall 85B is disposed below the first partition wall 85A. From the front edge of the second partition wall 85B, the third partition wall 85C extends downward. The third partition wall 85C is disposed in front of the return port 75A. The partition wall 85 defines a second space S2 within the housing 71.

[0037] When the heat medium circulates through the heating circuit B in the water heater 1, the heat medium is introduced into the housing 71 from the return port 75A. At this time, since the partition wall 85 separates the first space S1 and the second space S2, the momentum of the flow of the heat medium introduced from the return port 75A is reduced by the partition wall 85. Further, the heat medium with reduced momentum is guided forward (in the direction away from the liquid level electrode 72) by the first partition wall 85A and the second partition wall 85B. Therefore, the liquid level is suppressed from fluctuating near the lower end of the liquid level electrode 72, and the liquid level can be stabilized in the first space S1. Accordingly, the liquid level can be detected normally by the liquid level electrode 72.

[0038] [Inclined wall] As shown in FIG. 4, the housing 71 of the present embodiment includes an inclined wall 86 extending from the partition wall 85. Specifically, the inclined wall 86 extends obliquely upward in the front direction from the front edge of the second partition wall 85B and the upper edge of the third partition wall 85C. The inclined wall 86 guides the heat medium flowing outside the second space S2 in a direction away from the first space S1. Thereby, the liquid level can be detected even more normally by the liquid level electrode 72.

[0039] [Partition wall] As shown in Fig. 4, the housing 71 of the present embodiment includes an intermediate wall 87 extending from the left wall 78. The intermediate wall 87 is arranged between the liquid level electrode 72 and the filling port 80 in the front-rear direction. The intermediate wall 87 extends in the vertical direction as a whole. The intermediate wall 87 defines the first space S1 from the front side. The intermediate wall 87 includes a first intermediate wall 87A extending in the vertical direction, a second intermediate wall 87B extending obliquely downward to the rear from the lower end edge of the first intermediate wall 87A, and a third intermediate wall 87C extending downward from the lower end edge of the second intermediate wall 87B. The third intermediate wall 87C arranged at the lower end of the intermediate wall 87 is arranged above and behind the inclined wall 86. Thereby, the heat medium flowing from the second space S2 and guided by the inclined wall 86 can be further guided in a direction away from the first space S1.

[0040] In the housing 71, an incoming port side partition wall 95 extending from the front wall 76 and the left wall 78 is provided. The incoming port side partition wall 95 is arranged at the front and lower part in the housing 71 and partitions the space near the incoming port 75B in the housing 71.

[0041] [Water injection valve] As shown in Fig. 2, the hot water heater 1 of the present embodiment includes a cistern 70 for storing a heat medium for heating and a water injection valve 100 for automatically replenishing the heat medium into the cistern 70. As shown in Fig. 4, the water injection valve 100 is inserted and connected to the water injection port 80A. The water injection valve 100 has a valve body 101 having a first flow path P1 through which the heat medium flows, a discharge part 102 connected below the valve body 101 and having a second flow path P2 communicating with the first flow path P1, and a flange part 103 that contacts the opening edge of the water injection port 80A from above. The discharge part 102 has a discharge port 102A located at the lower end of the second flow path P2 and discharging the heat medium toward the cistern 70.

[0042] The flange part 103 is located at the lower end of the valve body 101 and is formed in an annular shape over the entire circumference. When the discharge part 102 is inserted into the water injection port 80A from above, the discharge part 102 is inserted into the water injection port 80A by the flange part 103 contacting the opening edge of the water injection port 80A. The lower end of the discharge part 102 is located at substantially the same height as the lower end of the water injection port 80A.

[0043] As shown in FIG. 5, the first flow path P1 includes a large-diameter circular flow path P1L and a small-diameter flow path P1S having a smaller diameter than the large-diameter flow path P1L when viewed from above. The large-diameter flow path P1L and the small-diameter flow path P1S are coaxially arranged.

[0044] As shown in FIGS. 3 and 5, the second flow path P2 is formed in a tapered shape that changes from an oval cross-section to a circular cross-section as it goes from the first flow path P1 side toward the discharge port 102A side. Among the inner walls constituting the second flow path P2, the wall surface on the left side in the illustration of FIG. 5 is a vertical surface 104 extending in the vertical direction. On the other hand, among the inner walls constituting the second flow path P2, the wall surface on the right side in the illustration of FIG. 5 is an inclined surface 105 that inclines away from the water supply port 80B as it approaches the discharge port 102A, as shown in FIG. 6.

[0045] On the discharge port 102A side of the inner wall of the second flow path P2 and on the side opposite to the inclined surface 105, a discharge port end surface 106 having an R shape is formed. The heat medium HC that has reached the discharge port 102A from the second flow path P2 is drawn and discharged to the left side in the illustration along the discharge port end surface 106 by the Coandă effect. Therefore, in addition to attempting to flow downward to the left in the illustration along the inclined surface 105, the heat medium HC is also drawn to the left side in the illustration by the discharge port end surface 106 and acts to move downward to the left in the illustration.

[0046] When the discharge port end surface 106 is formed as described above, the second flow path P2 can be formed using the slide type that forms the first flow path P1, so the structure of the mold does not have to be complicated. In addition, since the second flow path P2 has a tapered shape, turbulent flow is likely to occur. Moreover, by making the discharge port end surface 106 have an R shape, the incident angle of the heat medium HC can be made shallower by the Coandă effect.

[0047] FIG. 7 shows a state in which the heat medium HC is poured into the cistern 70 using the conventional water injection valve 200 for comparison with the water injection valve 100 of the present embodiment. For the configuration of the water injection valve 200 corresponding to the water injection valve 100 of the present embodiment, symbols in which the digit in the tens place is changed from 1 to 2 are used.

[0048] The heat medium HC flows from the first flow path of the valve body 201 into the second flow path of the discharge part 202 and then heads downward. The heat medium HC discharged vigorously from the discharge port 202A of the discharge part 202 hits the third partition wall 90C, and there is a possibility that a part of the rebounding heat medium HC may leak out of the water supply port 80B to the outside of the cistern 70.

[0049] On the other hand, according to the water injection valve 100 of the present embodiment, the heat medium HC flows from the first flow path P1 of the valve body 101 into the second flow path P2 of the discharge part 102, and then is discharged from the discharge port 102A toward the second partition wall 90B while changing its direction by the inclined surface 105. Since the heat medium HC hits the second partition wall 90B obliquely, it becomes easier to prevent the heat medium HC from rebounding. Even if a part of the heat medium HC rebounds at the second partition wall 90B, since it heads in a direction away from the water supply port 80B, it is possible to prevent the heat medium HC from leaking out of the water supply port 80B to the outside of the cistern 70.

[0050] <Other Embodiments> (1) In the above embodiment, the partition wall 90 includes the first partition wall 90A, the second partition wall 90B, and the third partition wall 90C, but the number of partition walls may be appropriately changed. Also, the shape and arrangement of the partition walls can be appropriately modified within the range where the object of the present disclosure can be achieved.

[0051] (2) In the above embodiment, the second flow path P2 that changes from an oval cross-section to a circular cross-section is exemplified, but other shapes may be used as long as the cross-section is a tapered shape. For example, a shape that changes from a circular cross-section to a circular cross-section may also be used.

[0052] (3) In the above embodiment, the discharge port end face 106 is formed on the inner wall of the second flow path P2, but a structure without the discharge port end face may also be used.

[0053] (4) In the above embodiment, as the water heater including the cistern 70 of the present disclosure, the water heater 1 including the hot water supply circuit A, the heating circuit B (circulation circuit), and the bathtub circuit C is exemplified, but the water heater may not include the heating circuit. Also, the heat medium circulating in the circulation circuit is not limited to water.

Description of Symbols

[0054] 1: Water heater (water supply heater) 2: Inner cylinder 3: Partition member 4: Water supply combustion chamber 5: Heating combustion chamber 6: Burner 6A: Water supply burner 6B: Heating burner 8: Ignition plug 9: Flame rod 10: Combustion fan 11: Water supply primary heat exchanger 12: Water supply secondary heat exchanger 13: Heating primary heat exchanger 14: Heating secondary heat exchanger 15: Exhaust hood 16: Exhaust port 17: Gas pipe 18: Gas branch pipe 19: Gas solenoid valve 20: Main gas solenoid valve 21: Gas proportional valve 22: Water supply pipe 23: Strainer 24: Water supply water volume sensor 25: Water supply inlet thermistor 26: Water volume control valve 27: Hot water outlet pipe 28: Water supply heat exchanger thermistor 29: Water supply hot water outlet thermistor 30: Bypass pipe 31: Water distribution valve 32: Heating return pipe 33: High-temperature radiator 34: Low-temperature radiator 35: Intermediate pipe 36: Heating circulation pump 37: Heating low-temperature thermistor 38: Heating low-temperature forward pipe 39: Built-in thermostatic valve 40: Heating high-temperature forward pipe 41: Heating high-temperature thermistor 42: Pipe for bath heating 43: Supplementary heating flow control valve 44: Heating bypass pipe 45: Bypass thermostatic valve 46: Bath heat exchanger 47: Bath return pipe 48: External bath return pipe 49: Bathtub 50: Bath circulation pump 51: Bath return thermistor 52: Water flow switch 53: Water level sensor 54: Bath forward pipe 55: External bath forward pipe 56: Bath forward thermistor 57: Drain pipe 58: Drain water solenoid valve 59: Bath water volume sensor 60: Check valve 61: Insulation cut-off valve 62: Drain pipe 63: Introduction pipe 64: Neutralizer 65: Drain pipe 66: Drain receiver 67: Drain discharge pipe 68: Water level electrode A: Water supply circuit B: Heating circuit C: Bath circuit 70: Cistern 71: Housing 71A: Housing body 71B: Cover body 72: Liquid level electrode 72A: First liquid level electrode 72B: Second liquid level electrode 74: Upper wall 74A: First upper wall 74B: Second upper wall 75: Bottom wall 75A: Return port 75B: Forward port 76: Front wall 76A: First front wall 76B: Second front wall 76C: Third front wall 77: Rear wall 78: Left wall 79A: First through hole 79B: Second through hole 80: Filling port 80A: Water injection port 80B: Water supply port 81: Makeup water solenoid valve 82: Makeup pipe 83: Overflow port 84: Overflow pipe 85: Partition wall 85A: First partition wall 85B: Second partition wall 85C: Third partition wall 86: Inclined wall 87: Intermediate wall 87A: First intermediate wall 87B: Second intermediate wall 87C: Third intermediate wall 90: Partition 90A: First partition 90B: Second partition 90C: Third partition 91: Guide wall portion 91A: First guide wall portion 91B: Inclined portion 95: Forward port side partition wall L1: Minimum liquid level L2: Maximum liquid level S1: First space S2: Second space 100: Water injection valve 101: Valve body 102: Discharge portion 102A: Discharge port 103: Flange portion 104: Vertical surface 105: Inclined surface 106: Discharge port end face P1: First flow path P1L: Large diameter flow path P1S: Small diameter flow path P2: Second flow path HC: Heat medium

Claims

Claim 1 a cistern for storing a heat medium for heating; a water injection valve for automatically replenishing the heat medium into the cistern, the water heater comprising: the cistern having a water inlet for manually replenishing the heat medium into the cistern, a water injection port to which the water injection valve is attached, and a partition wall located below the water injection port; the water injection valve having a valve body having a first flow path through which the heat medium flows, and a discharge portion having a second flow path connected to the lower side of the valve body and communicating with the first flow path; the discharge portion having a discharge port located at the lower end of the second flow path and discharging the heat medium toward the cistern; a water heater, wherein an inclined surface that inclines away from the water inlet as it approaches the discharge port is formed on the inner wall of the second flow path. Claim 2 the second flow path is formed in a tapered shape that changes from an oval cross section to a circular cross section as it goes from the first flow path side toward the discharge port side; the water heater according to claim 1, wherein a discharge port end surface having an R shape is formed on the discharge port side of the inner wall of the second flow path and on the side opposite to the inclined surface.

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