JP2015172403A - Channel selector valve and water heater equipped with same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a channel selector valve excellent in pressure resistance and a water heater equipped with the same.SOLUTION: A channel selector valve comprises: a body 19 including at least one inlet port 20 and a plurality of outlet ports 21 and 22; a shut-off valve 23 including a through-hole 27 and communicating the inlet port 20 with at least one of the outlet ports 21 and 22 by rotation operation; and a drive unit 25 driving the shut-off valve 23 to perform rotation operation about a predetermined axis Z. The shut-off valve 23 moves in a direction of the axis Z in response to an internal pressure of the body 19. Owing to this, even if an excessive pressure is generated in the channel selector valve, the pressure can be released and pressure resistance can be improved.

Description

  The present invention relates to a flow path switching valve and a hot water supply device including the same.

  Conventionally, as a flow path switching means used in this type of hot water supply apparatus, there is one using a ball-shaped valve element (see, for example, Patent Document 1).

  As shown in FIG. 7, the flow path switching means has a ball 29 that is a valve body, a ball 29 that contains the ball 29, and an A port 30, a B port 31, and a C port 32 that are three flow path ports. The valve body 33 and the drive unit 25 having an electric motor for rotating the ball 29 are configured.

  The valve body 33 has a valve chamber 34 for rotatably accommodating the ball 29, and an A port 30, a B port 31, and a C port 32 are formed so as to communicate with the valve chamber 34. The A port 30, the B port 31, and the C port 32 are arranged at intervals of 90 degrees, and the A port 30 and the B port 31 are arranged to face each other.

  The drive unit 25 has a shaft portion 35 for rotating the ball 29 around an axis parallel to the A port 30, and this shaft portion 35 is inserted through the opening of the valve body 33 and connected to the ball 29. Yes. A packing 36 is installed between the ball 29 and the A port 30 and between the ball 29 and the B port 31, and a hole is formed in the center of the packing 36. The shape of the hole and the ball 29 are opened. The first hole 37 and the second hole 39 coincide with each other.

  Since the packing 36 is compressed by the ball 29 and the valve main body 33, the fluid in the flow path is prevented from leaking through the outer periphery of the ball 29. A lower through hole 38 is opened in the ball 29 so as to face the C port 32 below the flow path switching means. FIG. 8 shows a cross-sectional view of the flow path switching means. As shown in FIG. 8, in the horizontal direction of the ball 29, a first hole 37 and a second hole 39 are opened so as to face the A port 30 and the B port 31, respectively. The hole 37 and the second hole 39 are disposed at 90 degrees with respect to each other. When the ball 29 is stopped at the position shown in FIG. 8, the fluid flowing in from the C port 32 flows out through the A port 30, but the ball 29 can be rotated 90 degrees clockwise as shown in FIG. The flow path is switched, and the fluid flowing in from the C port 32 flows out through the B port 31.

JP 2012-17902 A

  However, in the conventional configuration, when an excessive pressure is applied to a port that is not communicated by a hole provided in the valve body (ball), there is no place for the excessive pressure to escape. It had the subject that it might be damaged.

For example, when the hot water supply device is not used for a long period of time, it is necessary to remove the hot water from the hot water supply device in order to prevent freezing and breaking in the hot water supply device. However, in the conventional flow path switching means, water does not escape from a port that is not communicated by a hole provided in the valve body (ball). There was a problem that excessive pressure was generated and the flow path switching means might be damaged.

  This invention solves the said conventional subject, and it aims at providing the flow-path switching valve excellent in pressure | voltage resistance, and a hot-water supply apparatus provided with the same.

  In order to solve the conventional problem, the flow path switching valve of the present invention includes a main body having at least one inflow port and a plurality of outflow ports, a through hole, and the inflow port and the A closing valve body that communicates with at least one of the plurality of outflow ports; and a drive unit that rotates the closing valve body around a predetermined axis, wherein the closing valve body is a pressure inside the main body. In accordance with the above, it moves in the direction of the axis.

  Thereby, since a closing valve body moves according to the pressure inside a main body, even if an excessive pressure arises inside the piping path | route where the flow-path switching valve is arrange | positioned, the pressure can be released. Therefore, for example, in a hot water supply device, even when the water inside the pipe freezes when not in use for a long time, the excessive pressure generated inside the pipe can be released.

  ADVANTAGE OF THE INVENTION According to this invention, the flow-path switching valve excellent in pressure | voltage resistance and the hot water supply apparatus provided with the same can be provided.

1 is a schematic configuration diagram of a hot water supply device including a flow path switching valve according to Embodiment 1 of the present invention. Sectional drawing which shows the state which the flow-path switching valve is moving to the outflow port side (A) Bottom view of closing valve body of same flow path switching valve, (b) Front view of closing valve body of same flow path switching valve Bottom view when the flow path switching valve is switched to the hot water storage lower flow path Top view when the flow path switching valve is switched to the hot water storage lower flow path Sectional drawing which shows the state which the flow-path switching valve is moving to the inflow port side Sectional view of a conventional flow path switching valve Sectional view when the flow path switching valve is viewed from below Another sectional view of the flow path switching valve when viewed from below

  The present invention provides a main body having at least one inflow port and a plurality of outflow ports, a closing valve body having a through-hole and communicating the at least one of the inflow ports and the plurality of outflow ports by a rotation operation. A drive unit that rotates the closing valve body around a predetermined axis, and the closing valve body moves in the direction of the shaft according to the pressure inside the main body. This is a flow path switching valve.

  Thereby, since a closing valve body moves according to the pressure inside a main body, even if an excessive pressure arises inside the piping path | route where the flow-path switching valve is arrange | positioned, the pressure can be released. Therefore, for example, in a hot water supply device, even when the water inside the pipe freezes when not in use for a long time, the excessive pressure generated inside the pipe can be released. As a result, it is possible to provide a flow path switching valve excellent in pressure resistance and a hot water supply device including the same.

  According to a second aspect of the present invention, in the closing valve body, when the area of the first pressure receiving surface exposed to the inflow port side is S1, and the area of the second pressure receiving surface exposed to the outflow port side is S2, S1 > S2.

  The force for moving the closing valve body in the axial direction is determined by the product of the pressure generated on the pressure receiving surface of the closing valve body and the area of the pressure receiving surface. Here, since the area S1 of the first pressure receiving surface is larger than the area S2 of the second pressure receiving surface 29b, the closing valve body is moved in the axial direction even if the pressure generated on the first pressure receiving surface side is small. be able to. On the other hand, since the area S2 of the second pressure receiving surface is relatively small, the closing valve body does not move unless the pressure generated on the second pressure receiving surface side becomes a constant pressure.

  Therefore, the closing valve body moves at the normal pressure in the pipe connected to the inflow port side or the normal pressure of the fluid flowing in from the inflow port side. On the other hand, the excessive pressure generated in the pipe connected to the outflow port side The closing valve body moves in response to various pressures. That is, the closing valve body moves passively without using an elastic body such as a spring in response to excessive pressure generated in the main body (in the pipe connected to the main body). As a result, excessive pressure can be released and pressure resistance can be improved.

  According to a third aspect of the present invention, there is provided a hot water storage tank for storing hot water, a water supply pipe for supplying water to the hot water storage tank, a pressure reducing valve provided in the water supply pipe, a heating means for heating the hot water, and a lower part of the hot water storage tank. A heating circuit for returning hot water to the upper or lower part of the hot water storage tank via the heating means, the flow path switching valve according to claim 1 or 2 is provided in the heating circuit, and the flow path The hot water supply apparatus is characterized in that the hot water is returned to the upper or lower part of the hot water storage tank by a switching valve.

  As a result, even when an excessive water pressure is applied from the pipe connected to the outflow port side of the closed flow path switching valve, the closing valve body moves in the axial direction to open and release the pressure. It becomes. Moreover, the hot water in the pipe connected to the outflow port side of the flow path switching valve can be discharged out of the device through the closing valve body. As a result, it is possible to prevent the flow path switching valve from being damaged even if hot water in the pipe is frozen when not in use for a long time.

  According to a fourth aspect of the present invention, the closing valve body moves in a direction opposite to the inflow port with respect to the shaft at an internal pressure on the inflow port side greater than 0 kPa and not more than a set pressure of the pressure reducing valve. As described above, the area of the first pressure receiving surface is adjusted.

  As a result, the closing function works when the internal pressure in the flow path of the flow path switching means is generally lower than the set pressure of the pressure reducing valve installed in the hot water storage hot water supply device. When the internal pressure drops, for example, when the hot water in the hot water storage tank is drained, the shut-off valve body opens and the hot water in the pipe on the outflow port side of the closed channel switching valve is closed. It can be discharged out of the device through the valve body.

  Embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a hot water supply apparatus including a flow path switching valve according to Embodiment 1 of the present invention. In FIG. 1, the hot water supply apparatus includes a hot water tank 1 and a heat pump heat source 2 as heating means. The water supplied from the water supply source passes through the water supply pipe 3 and the pressure reducing valve 4, branches to the lower part of the hot water tank 1 and the hot water supply mixing valve 5, and the water introduced from the lower part of the hot water tank 1 is stored in the hot water tank 1.

  The lower part of the hot water tank 1 and the heat pump heat source 2 are connected by a heat pump forward pipe 7 via a boiling pump 6. A compressor 8 is built in the heat pump heat source 2, and heat is exchanged with hot water introduced into the heat pump heat source 2 to raise the temperature, and the heat pump return pipe 9 and the hot water tank lower return pipe 10 are passed through. It is designed to return to the bottom. A flow path switching valve 11 is provided between the heat pump return pipe 9 and the hot water tank lower return pipe 10.

  In the initial stage of boiling, the temperature of the hot water returning from the heat pump heat source 2 is low (for example, less than 60 ° C.). In this case, the flow path of the flow path switching valve 11 is used to boil the hot water. It supplies to the lower part of the street hot water tank 1. When the hot water temperature returned from the heat pump heat source 2 becomes high (for example, 60 ° C. or higher), the flow path of the flow path switching valve 11 passes through the hot water tank return pipe 12 and returns to the upper part of the hot water tank 1. It is like that. That is, the heat pump forward pipe 7, the heat pump return pipe 9, the hot water tank lower return pipe 10 or the hot water tank upper return pipe 12 are connected to each other, and the hot water in the lower part of the hot water tank 1 flows toward the upper part of the hot water tank 1, A heating circuit for heating the hot water in the tank 1 is formed.

  The hot water stored in the upper part of the hot water tank 1 and the water branched from the water supply pipe 3 are mixed by the hot water supply mixing valve 5 and discharged from the faucet 18 through the hot water temperature sensor 16 and the flow rate sensor 17. An inlet water temperature sensor 13 for measuring the incoming water temperature is provided at the inlet of the heat pump heat source 2, and a hot water temperature sensor 14 for detecting the outlet temperature of the hot water from the heat pump heat source 2 is provided at the outlet. 15 is sent. The detected temperature is used to adjust the output of the compressor 8, and the flow path switching valve 11 is controlled by the temperature information of the hot water temperature sensor 14.

  FIG. 2 shows a cross-sectional view of the flow path switching valve 11 of the first embodiment. In FIG. 2, at least one inflow path (inflow port 20) and a plurality of outflow paths (outflow ports 21 and 22) are provided in the main body 19 of the flow path switching valve 11. In the present embodiment, at least three flow paths are provided in the main body 19, and the hot water heated by the heat pump heat source 2 is returned to the inflow port 20 side by being connected to the heat pump return pipe 9. The heat pump return flow path is configured. A hot water tank upper return pipe 12 is connected to the first outflow port 21 side, and constitutes a hot water tank upper flow path for sending hot water to the upper part of the hot water tank 1. A tank lower return pipe 10 is connected to form a hot water tank lower flow path for sending hot water to the lower part of the hot water tank 1. In the present embodiment, the main body 19 is integrally formed. However, the main body 19 is configured by combining a plurality of members as long as the main body 19 has the flow paths in at least the three directions described above. It does not matter.

  A rotary closing valve body 23 is installed inside the main body 19 of the flow path switching valve 11, and the rotating shaft 24 of the rotary closing valve body 23 is driven by a drive unit 25 having an electric motor. Accordingly, the rotary closing valve body 23 rotates around the axis Z, and the flow path is switched. An O-ring 26 is disposed around the rotary shaft 24 to prevent the fluid in the main body 19 of the flow path switching valve 11 from leaking to the outside. Thereby, the shut-off valve body 23 is pivotally supported by the main body 19. Further, as will be described later, the shut-off valve body 23 slides (moves) along the main body 19 in the Z-axis direction. FIG. 3 shows a bottom view and a front view of the closing valve body 23. As shown in FIG. 3, the closing valve body 23 is provided with a through hole 27. The through hole 27 coincides with the outlet to the first outlet port (hot water tank lower channel) 21 opened in the body 19 of the channel switching valve 11 and the outlet to the second outlet port (hot water tank upper channel) 22. It is preferable to have an opening shape.

  FIG. 4 shows a bottom view when the flow path switching valve 11 is switched to the hot water tank lower flow path 21 side. The through hole 27 opened in the rotary closing valve body 23 in the main body 19 of the flow path switching valve 11 and the outlet to the hot water tank lower flow path 21 coincide with each other, and the hot water flowing out from the heat pump return pipe 9 flows through the flow path. It flows from the inflow port 20 of the switching valve 11 and flows into the hot water tank lower return pipe 10 via the hot water tank lower flow path 21. Thereafter, the hot water is supplied from the lower part of the hot water tank 1 into the hot water tank 1.

FIG. 5 shows a bottom view when the flow path switching valve 11 is switched to the hot water tank upper flow path 22 side. The through hole 27 opened in the rotary closing valve body 23 in the main body 19 of the flow path switching valve 11 and the hot water storage tank upper flow path 22 coincide with each other, and the hot water flowing out from the heat pump return pipe 9 flows into the flow path switching valve 11. It flows in from the inflow port 20 and flows into the hot water tank upper return pipe 12 through the hot water tank upper flow path 22. after that,
It is supplied into the hot water tank 1 from the upper part of the hot water tank 1. In order to switch the outlet of the hot water flowing in from the heat pump return pipe 9 from the hot water tank upper flow path 22 to the hot water tank lower flow path 21, the drive unit 25 is driven to rotate the rotary shut-off valve body 23 at a predetermined angle (this embodiment). This can be realized by rotating 180 degrees.

  Next, the operation will be described. For hot water storage in the hot water tank 1, the position of the rotary closing valve body 23 is set so that the hot water flowing from the inflow port 20 flows to the hot water tank upper flow path 22 through the flow path switching valve 11. Thereby, hot water is stored in the upper part of the hot water tank 1. When hot water storage in the hot water storage tank 1 is completed, the rotary closing valve body 23 is set at a predetermined angle (so that hot water flowing from the inflow port 20 flows into the hot water tank lower flow path 21 through the flow path switching valve 11. In this embodiment, it is rotated 180 degrees. As a result, the hot water tank upper flow path 22 is closed by the rotary closing valve body 23 to prevent the hot water stored in the upper part of the hot water tank 1 from being convected to the lower part of the hot water tank.

  FIG. 6 shows a cross section of the flow path switching valve 11 in a state where excessive pressure is generated in the pipe connected to the outflow port (21, 22) side of the flow path switching valve 11. When the supply of hot water to the hot water tank 1 is completed, the hot water tank upper flow path 22 is closed by the rotary closing valve body 23, so that if the pressure in the hot water tank upper return pipe 12 rises due to freezing or the like, it rotates. The closed valve body 23 of the type moves below the flow path switching valve 11 and generates a clearance 28. As a result, the outflow port (hot water tank upper flow path 22) closed at that time is opened and the plurality of outflow ports (21, 22) communicate with each other, so that the pressure increase in the hot water tank upper return pipe 12 is eliminated. Thus, the flow path switching valve 11 can be prevented from being damaged.

  Further, when hot water is drawn out from the hot water tank 1 so that the hot water supply device is not used for a long period of time, the internal pressure of the flow path switching valve 11 (particularly, the internal pressure on the inflow port 20 side) becomes approximately the same as the atmospheric pressure. Since the pressure difference between the internal pressure on the 20 side and the internal pressure on the outflow port (21, 22) side increases, the valve closing function of the rotary closing valve body 23 that has closed the hot water tank upper flow path 22 decreases, or To lose. Therefore, the hot water in the hot water tank return pipe 12 passes through the shut-off valve body 23 and the heat pump return pipe 9 and is discharged outside the hot water supply device. Breakage of the switching valve 11 can be prevented.

  Further, the shut-off valve body 23 of the flow path switching valve 11 has a pressure receiving surface S2 (S2 ′ or S2 ″) in which the area S1 of the pressure receiving surface exposed on the inflow port 20 side is exposed on the outflow port (21, 22) side. It is comprised so that it may become larger. The force for moving the closing valve body 23 in the axial direction is determined by the product of the pressure generated on the pressure receiving surface of the closing valve body 23 and the area of the pressure receiving surface. Here, since the area S1 of the first pressure receiving surface 29a is larger than the area S2 of the second pressure receiving surface 29b, even if the pressure generated on the first pressure receiving surface 29a side is small, the closing valve body can be moved in the axial direction ( In the direction of closing the outflow ports 21 and 22 side). On the other hand, since the area S2 of the second pressure receiving surface 29b is relatively small, the closing valve body does not move to the inflow port 20 side unless the pressure generated on the second pressure receiving surface 29b side becomes a constant pressure.

  Therefore, the closing valve body 23 is moved by the normal pressure in the pipe connected to the inflow port 20 side or the normal pressure of the fluid flowing in from the inflow port 20 side, thereby closing the outflow ports (21, 22). Since the outflow ports (21, 22) communicate with each other and hot water does not flow between the two, the boiling operation can be performed, and the heating circuit is also provided after the boiling operation. It is possible to prevent hot water from flowing inside.

  On the other hand, the closing valve body 23 moves in response to an excessive pressure generated in the pipe connected to the outflow port (21, 22) side. That is, the closing valve body 23 passively moves without using an elastic body such as a spring in accordance with an excessive pressure generated in the main body 19 (also in the pipe connected to the main body 19). As a result, excessive pressure can be released and pressure resistance can be improved.

  Further, the rotary closing valve body 23 of the flow path switching valve 11 moves upward as the internal pressure of the flow path switching valve 11 increases. At that time, the rising force is applied to the rotating shaft 24 of the closing valve body 23. It can be determined by the pressure applied to the pressure-receiving surface of the atmosphere opening portion. Thereby, force is applied in the direction of closing the outflow ports (21, 22) of the flow path switching valve 11. Here, when the set pressure of the pressure reducing valve 4 generally installed in the hot water supply device is 170 kPa and the area of the pressure receiving surface S2 on the atmosphere opening side of the closing valve body 23 is 60 mm ^ 2, the closing valve body The closing force applied to 23 (the rising force necessary to close the outflow ports 21 and 22) F is F = 170 kPa × 60 mm ^ 2/1000 = 10.2 N.

  The force required for sliding the closing valve body 23 is governed by the sliding resistance of the O-ring 26, and the force required for sliding the O-ring 26 increases as the compression ratio of the O-ring 26 increases. Here, when the sliding force of the O-ring is set to 10.2 N or less, it becomes possible to close the outflow port (21, 22) side of the flow path switching valve 11 with the set pressure 170 kPa of the pressure reducing valve 4. On the other hand, if the sliding force of the O-ring 26 is set to 10.2 N or more, the set pressure of the pressure reducing valve 4 cannot close the outflow ports (21, 22) of the flow path switching valve 11, and the closing valve body 23 When leakage occurs and hot water is stored in the hot water tank 1, the hot water flows into the lower part of the hot water tank 1, and hot water flowing into the lower part of the hot water tank 1 flows from the lower part of the hot water tank 1. It flows to the heat pump heat source 2 through the heating circuit. This becomes a cause of reducing the heat exchange efficiency in the heat pump heat source 2.

  Even when hot water is not stored in the hot water tank 1, the hot water in the hot water tank upper return pipe 12 passes through the heat pump return pipe 9 to the lower part of the hot water tank 1 because the valve closing function of the hot water tank upper flow path 22 is low. A convection phenomenon occurs. As a result, hot water is mixed in the upper and lower parts of the hot water tank 1 and the laminated structure of the hot water in the hot water tank 1 is destroyed, so hot hot water flows through the heat pump heat source 2 and the heat exchange efficiency is lowered. Therefore, it is necessary for the closing valve body 23 to close at an internal pressure equal to or lower than the set pressure of the pressure reducing valve 4. In the present embodiment, the closing valve body 23 has an inner pressure on the inflow port 20 side that is larger than 0 kPa and lower than a set pressure (for example, 170 kPa) of the pressure reducing valve 4, and has an outlet port (21, 22) side. Although it is configured to close, a low pressure when closing indicates a low pressure when opening. Therefore, the shut-off valve body 23 is configured to close the outflow port 20 side at a value where the internal pressure on the inflow port 20 side is larger than 100 kPa and lower than the set pressure (for example, 170 kPa) of the pressure reducing valve 4. More preferred.

  Further, when the set pressure of the pressure reducing valve 4 is increased, the ascending force F applied to the rotary closing valve body 23 increases, so that the closing performance of the closing valve body 23 is improved. Since the main body 19 of the flow path switching valve 11 is firmly in contact and the frictional resistance is increased, the driving torque of the driving unit 25 must be increased, and accordingly, the strength of the rotary shaft 24 of the closing valve body 23 needs to be increased. This leads to an increase in the size of the flow path switching valve 11, an increase in power consumption, and an increase in cost, such as expansion of the shaft diameter and change to a high-strength material. Therefore, it is possible to reduce power consumption, size, and cost by configuring the shutoff valve body 23 to close the flow path to the upper or lower part of the hot water tank 1 at a set pressure 170 kPa or less of the pressure reducing valve 4 of a general hot water supply device. Optimization can be achieved.

  As described above, the flow path switching valve 11 of the present invention is characterized in that the closing valve body 23 operates in each of the first direction in which it is actively driven and the second direction in which it is passively moved. And That is, the closing valve body 23 of the present embodiment performs a rotating operation by the driving unit 25 as an active operation for switching the flow path. Further, the closing valve body 23 performs a sliding operation in the direction of the rotation shaft as a passive operation corresponding to the pressure inside the main body 19. With this sliding operation, the inflow port 20 and the outflow ports (21, 22) communicate with each other, and the pressure resistance can be improved by releasing the excessive pressure generated in each port.

  The operation of the closing valve body 23 is not limited to the combination of the rotation operation and the linear operation. For example, the linear motion of the present embodiment may be used as an active motion for switching the flow path, and a rotational motion may be used as a passive motion according to the pressure inside the main body 19. Further, any of the plurality of operations may be a linear operation, or any of them may be a rotation operation. That is, as the direction in which the object moves, any two movements are selected from a total of six movements of the rotation movement around the three axes and the linear movement in the three axis directions, and one of them is set as an active movement. The other may be selected as a passive operation.

  The flow path switching valve 11 of the present embodiment does not require the closing valve body 23 to be urged by an elastic body such as a spring, and the closing valve body 23 itself operates. For example, some well-known pressure relief valves energize the valve body by incorporating an elastic body of an arbitrary restoring force into the main body, and some of them respond to excessive pressure, but the structure becomes complicated and the valve The size itself increases. However, the flow path switching valve 11 of the present embodiment can cope with an excessive pressure with a simple configuration without incorporating an elastic body inside.

  ADVANTAGE OF THE INVENTION According to this invention, the flow-path switching valve excellent in the pressure | voltage resistance which can release the excessive pressure which arises in piping can be implement | achieved, and it can be used as a hot water supply apparatus for business and household use.

1 Hot water tank 2 Heat pump heat source (heating means)
DESCRIPTION OF SYMBOLS 3 Water supply pipe 4 Pressure reducing valve 5 Hot water supply mixing valve 6 Boiling pump 7 Heat pump forward pipe 8 Compressor 9 Heat pump return pipe 10 Hot water tank lower return pipe 11 Flow path switching valve 12 Hot water tank upper return pipe 13 Incoming water temperature sensor 14 Hot water temperature sensor 15 Control board 16 Hot water supply temperature sensor 17 Flow rate sensor 18 Faucet 19 Main body 20 Heat pump return flow path (inflow port)
21 Hot water storage tank lower flow path (first outflow port)
22 Hot water tank upper flow path (second outflow port)
23 Closing valve body 24 Rotating shaft 25 Drive unit 26 O-ring 27 Through hole 28 Clearance

Claims (4)

A body having at least one inlet port, a plurality of outlet ports;
A closing valve body having a through-hole and communicating with at least one of the inflow port and the plurality of outflow ports by a rotation operation;
A drive section for rotating the stop valve body around a predetermined axis,
The flow path switching valve, wherein the closing valve body moves in the direction of the shaft according to the pressure inside the main body. When the area of the first pressure receiving surface exposed on the inflow port side is S1 and the area of the second pressure receiving surface exposed on the outflow port side is S2, the closing valve body satisfies S1> S2. The flow path switching valve according to claim 1, wherein: Hot water and hot water storage tank,
A water supply pipe for supplying water to the hot water storage tank;
A pressure reducing valve provided in the water supply pipe;
Heating means for heating the hot water;
A heating circuit for returning hot water in the lower part of the hot water tank to the upper or lower part of the hot water tank through the heating means,
The flow path switching valve according to claim 1 or 2 is provided in the heating circuit,
A hot water supply apparatus that switches whether the hot water is returned to an upper part or a lower part of the hot water storage tank by the flow path switching valve. The closing valve body is configured to move in the direction opposite to the inflow port with respect to the shaft at an internal pressure on the inflow port side greater than 0 kPa and less than or equal to a set pressure of the pressure reducing valve. The hot water supply apparatus according to claim 3, wherein an area of the pressure receiving surface of 1 is adjusted.