Pressure reducing valve

Abstract

To provide a pressure reducing valve which prevents water from entering a spring housing chamber without increasing the sliding resistance of the sliding valve and has a smooth pressure reducing function. [Solution] The valve includes a valve body 2 with a cylindrical internal space, a valve shaft 3 with a cylindrical internal nozzle for discharging the supplied water, a pressure-receiving section with an annular flat surface 22 slidably arranged along the inner peripheral wall of the valve body 2, a cylindrical guide 23 slidably arranged along the outer peripheral surface of the internal nozzle, a sliding valve 20 with a water-stop packing 30 that can abut against the tip of the internal nozzle, and a spring 42 that presses the sliding valve 20 to the discharge side, and when the load received by the annular flat surface 22 due to an increase in water pressure exceeds the pressing force of the spring 42, the water-stop packing 30 abuts against the tip of the internal nozzle to stop water flow. The sliding valve 20 slides smoothly due to an X-ring, and the spring housing section 43 is designed to maintain airtightness.

Description

[Technical field]

[0001] This relates to a pressure reducing valve that is attached to equipment and piping that supplies water, such as water heaters and shower heads. [Background technology]

[0002] Patent Document 1 describes a single-shaft pressure reducing valve that has a sliding valve that is pressed in the valve opening direction by a coil spring housed in an air chamber, and is configured so that when the pressure on the secondary side (the supply side) increases, the sliding valve moves to a closed position against the spring force of the coil spring. This pressure reducing valve is provided to prevent problems associated with an increase in pressure caused by the sudden stopping of water that had been flowing forcefully through the hose when the faucet of a connected shower head is closed to stop the water flow, such as the hose becoming detached from the shower head. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-193874 Summary of the Invention [Problem to be solved by the invention]

[0004] The single-shaft pressure reducing valve described in the above Patent Document 1 houses a coil spring in an air chamber that elastically presses the sliding valve. The air chamber is a space that guides the sliding valve and has a hole that communicates with the outside air, so if water enters the air chamber, the water will leak to the outside through the hole that communicates with the outside air. For this reason, an O-ring is attached to the outer periphery of the sliding valve to prevent water from entering the air chamber, but to prevent this water leakage, the O-ring needs to be tightly attached to the inner wall surface of the air chamber without any gaps. However, if the O-ring is too tightly attached, the friction resistance will increase, preventing the sliding of the sliding valve, and there is a possibility that the function of the single-shaft pressure reducing valve will not be fully exerted.

[0005] The present invention has been devised in consideration of the above circumstances, and aims to provide a pressure reducing valve which prevents water from leaking to the outside by configuring the spring accommodation chamber that accommodates the spring as a sealed air chamber, and which can prevent water from entering the spring accommodation chamber without increasing the sliding resistance of the sliding valve, and which has a smooth pressure reducing function. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention has the following configuration. A pressure reducing valve having a supply side connection means for connecting to a piping on a water supply side and a discharge side connection means for connecting to another piping or device on a discharge side of the supplied water, A housing having a cylindrical internal space; a cylindrical internal nozzle provided in the internal space of the housing and configured to discharge the supplied water from a tip thereof; a sliding valve including a ring-shaped pressure receiving portion slidably provided along an inner peripheral wall of the housing, a cylindrical guided portion slidably provided along an outer peripheral surface of the inner nozzle, and a water stop packing capable of contacting a tip of the inner nozzle; A spring is provided to press the sliding valve to the discharge side, The sliding valve moves to the supply side when the load received by the pressure-receiving part due to an increase in water pressure exceeds the pressing force of the spring, and abuts a water-stopping gasket against the tip of the internal nozzle to stop the water flow.

[0007] The pressure reducing valve has the following configuration. An X-ring is attached to the sliding portion of the annular pressure-receiving portion that slides in contact with the inner wall of the cylinder that forms the internal space of the housing, and to the outer peripheral surface of the internal nozzle that slides in contact with the inner peripheral surface of the guided portion, and is characterized in that the X-ring is used to maintain the airtightness of the spring accommodating chamber that accommodates the spring.

[0008] The pressure reducing valve has the following configuration. The cylinder has an inner surface provided with a contact surface against which an annular flat surface provided on a sliding contact portion of the sliding valve comes into contact, A conical inclined surface is provided at the boundary between the contact surface and a pipe section communicating with a water outlet, thereby exposing the inner periphery of the annular plane to the water flow passing through the pipe section. Effect of the Invention

[0009] The pressure reducing valve according to the present invention has the advantage that it is possible to provide a pressure reducing valve that does not leak water to the outside and that operates stably and with fast response due to the smooth operation of the sliding valve. [Brief description of the drawings]

[0010] [Figure 1] 1 is an external perspective view of a pressure reducing valve according to an embodiment of the present invention; [Diagram 2] 1 is a cross-sectional view of a pressure reducing valve according to an embodiment of the present invention. [Diagram 3] 1 is an external perspective view of a pressure reducing valve according to an embodiment of the present invention; [Figure 4] 1 is a cross-sectional view of a pressure reducing valve according to an embodiment of the present invention in a water-stopped state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1(a) is an external perspective view of a pressure reducing valve 1 according to this embodiment as viewed from the water discharge side, and FIG. 1(b) shows an external perspective view of the pressure reducing valve 1 as viewed from the water supply side. The pressure reducing valve 1 has a single-shaft valve body 2 formed as a short, hollow cylindrical housing, and a single-shaft valve shaft 3 screwed to the rear end of the single-shaft valve body 2. A male thread 4 is provided at the tip of the single-shaft valve body 2, which is the tip of the pressure reducing valve 1, and a female thread 5 is provided at the rear end of the single-shaft valve shaft 3, which is the rear end of the pressure reducing valve 1. The male thread 4 at the tip of the pressure reducing valve 1 is a discharge side connection means provided on the water discharge side, and is connected to instruments and piping that use water. In addition, the female thread 5 at the rear end of the pressure reducing valve 1 is a supply side connection means provided on the water supply side, and is connected to the piping and equipment of the water supply system that supplies water.

[0012] Fig. 2 shows a cross-sectional view of the pressure reducing valve 1, and Fig. 3 shows an exploded perspective view of the elements that make up the pressure reducing valve 1. In Fig. 2, an arrow H indicates the direction in which water flows in normal use. The valve body 2 has a male thread 4 at its tip, and a female thread 6 is formed on the inner surface of the opposite end for screwing the valve shaft 3. The opposite end of the valve shaft 3 has a female thread 5 as a supply side connection means at its rear end, and is provided with a male thread 10 to screw into the female thread 6 of the valve body 2, and an internal nozzle 11 formed as a protruding cylindrical shaft, and the outer shape of the rear end is hexagonal. An O-ring 17 is provided at the joint between the valve body 2 and the valve shaft 3, which are joined by screwing the female thread 6 into the male thread 10, to maintain airtightness and watertightness between the two components.

[0013] A water discharge port 12 is provided at the tip of the male screw 4 provided on the single-shaft valve body 2, and is connected via a pipe line 13 of the same diameter as the discharge port 12 to a cylinder 14 having a larger diameter than the pipe line 13. The inner surface of the cylinder 14, which is the boundary with the pipe line 13, is formed with a conical inclined surface 15 and a contact surface 16 perpendicular to the axial direction. A sliding valve 20 is provided inside the cylinder 14 so as to be movable along the axial direction. The sliding valve 20 has a piston-shaped sliding contact portion 21 on its outer periphery which slides against the inner surface of the cylinder 14, and the tip surface of the sliding contact portion 21 forms an annular flat surface 22 which abuts against the abutment surface 16 provided at the tip inside the cylinder 14. The annular flat surface 22 forms a pressure receiving portion which transmits the pressure of the water flowing through the pipe portion 13 to the sliding valve 20.

[0014] The sliding valve 20 will be described in more detail. The sliding valve 20 has a cylindrical guide 23 formed with an outer diameter smaller than that of the sliding contact part 21 behind the sliding contact part 21, and has a packing holding part 24 protruding from the annular flat surface 22 of the sliding contact part 21. The inner surface of the guide 23 forms the guided part 18 that is slidably guided by the cylindrical part 50 that constitutes the internal nozzle 11. An opening 26 of a flow path 25 that communicates with the inside of the guide 23 is provided between the watertight packing holding part 24 and the sliding contact part 21. The watertight packing retaining portion 24 is a portion that retains the packing member 30 near the center of the position where the sliding contact portion 21 is provided. In this embodiment, the packing member 30 has a base portion 32 having a contact plane 31 perpendicular to the axis, and a thin cylindrical portion 33 that protrudes from the base portion 32 toward the discharge port 12. A groove 34 is provided on the outer periphery of the base 32, and the watertight gasket 30 is held in the watertight gasket holding portion 24 by fitting the groove 34 with a gap provided on the inner edge of a circular opening 35 formed at the tip of the watertight gasket holding portion 24.

[0015] The sliding contact part 21 of the sliding valve 20 having an annular flat surface 22 has a groove 40 on its outer periphery, and an X-ring (first X-ring) 41 is fitted into the groove 40. The X-ring is a packing member with an X-shaped cross section and protrusions on four orthogonal sides that serve as contact parts. The X-ring 41 contacts the inner surface of the cylinder 14, and prevents water from entering the spring housing part 43 formed by the inner surface of the cylinder 14 and the guide 23 side of the sliding contact part 21 housing the spring 42. The spring 42 is a coil spring, which is disposed between the sliding contact portion 21 and a synthetic resin spacer 44 attached to the single-axis valve shaft 3. In the normal state, the spring 42 presses against the sliding contact portion 21, causing the annular flat surface 22 to come into contact with the abutment surface 16 inside the cylinder 14.

[0016] The inner surface of the guide 23 provided behind the sliding portion 21 is in sliding contact with the outer surface of the cylindrical portion 50 of the internal nozzle 11 provided on the single-axis valve shaft 3, and is adapted to move backward when a force is applied to compress the spring 42 against the sliding valve 20. A groove 51 is provided on the surface of the cylindrical portion 50, and an X-ring (second X-ring) 52 is fitted inside the groove 51. The X-ring 52 blocks water from entering the gap between the inner peripheral surface of the guide 23 and the outer peripheral surface of the cylindrical portion 50, and prevents water from entering the spring accommodating portion 43.

[0017] The inside of the cylindrical portion 50 that constitutes the internal nozzle 11 forms a water flow conduit 54 that communicates with a water supply port 53 having a female thread 5 formed therein, and water is sprayed from an opening 55 provided on the tip surface of the internal nozzle 11. The tip surface of the internal nozzle 11 is adapted to come into contact with the abutment plane 31 of the water stop packing 30 when the sliding valve 20 retracts, and at that time the water stop packing 30 closes the opening 55, thereby blocking the water spray from the internal nozzle 11. In other words, the sliding of this sliding valve 20 functions as a valve that controls the water spray.

[0018] At the entrance of the water pipe 54 inside the water supply port 53 of the single valve shaft 3, a strainer 57 is provided which, together with a packing 56, prevents the intrusion of dirt and has a flow straightening effect.

[0019] The pressure reducing valve 1 having the above-described configuration is a device that is placed in the middle of a pipe, and in the event of a sudden increase in pressure caused by the closing of a water tap in the equipment or pipe located downstream of the pressure reducing valve 1, it blocks water flowing into the downstream equipment or pipe. When the water pressure in the pipeline 13 rises due to inertia caused by the sudden cessation of flowing water, pressure acts on the inner periphery of the abutment surface 16 facing the inclined surface 15 inside the cylinder 14, retracting the sliding valve 20 against the spring 42. The inner periphery of the abutment surface 16 is exposed to the flowing water in the pipeline 13 by providing the inclined surface 15, and is therefore the first to be subjected to fluctuations in water pressure. Note that the inclined surface 15 may be replaced by a shape that creates a stepped space, but in this embodiment the inclined surface 15 is provided so as not to create resistance to the flow of water. When the sliding valve 20 begins to move backward, the outer periphery of the abutment surface 16, which was in contact with the annular plane 22, also becomes subject to water pressure, and the entire surface of the abutment surface 16 becomes subject to a pressing force from the water pressure P, causing the sliding valve 20 to move backward quickly at a speed corresponding to the force pressing against the entire surface of the abutment surface 16.

[0020] 4 shows a cross-sectional view of the pressure reducing valve 1 with the sliding valve 20 retracted. When the sliding valve 20 retracts, the contact plane 31 of the water stop packing 30 abuts against the tip of the cylindrical portion 50 constituting the internal nozzle 11, blocking the opening 55 and blocking the excessively pressurized water pressure. In addition, the retraction of the sliding valve 20 increases the volume of the portion indicated by the dotted line 18. This increase in volume functions as a buffer to receive water that flows back from the discharge port 12 into the pipe portion 13, thereby mitigating impacts that occur within the piping and equipment. In addition to the impact of the water flow caused by the closure, the sliding valve 20 also operates when the static pressure on the supply side exceeds the specified pressure, so it also functions as a pressure reducing valve. The set pressure can be adjusted by selecting the spring to be used or the thickness of the spacer 44 supporting the spring 42.

[0021] The spring housing 43 housing the spring 42 that presses the sliding valve 20 is kept airtight by a first X-ring 41 that contacts the inner surface of the cylinder 14 and a second X-ring 52 that contacts the cylindrical portion 50. The X-ring is used to reduce sliding resistance while keeping the airtightness of the spring housing 43, allowing the sliding valve 20 to move smoothly.

[0022] The pressure reducing valve described above is one embodiment and does not limit the present invention. Substitution and combination with other means within the scope of the present invention also fall within the technical scope of the present invention, provided that the gist of the present invention is not deviated from. [Industrial Applicability]

[0023] This device can be used as a pressure reducing valve connected to piping or equipment, as well as a component built into equipment. [Explanation of symbols]

[0024] 1 Pressure reducing valve 2 Single shaft valve body 3 Single shaft valve stem 4 Male thread 5 Female thread 6 Female thread 10 Male thread 11 Inner nozzle 12 Outlet 13 Pipe section 14 cylinders 15 Slope 16 Contact surface 17 O-ring 20 Slide valve 21 Sliding contact part 22 Circular Plane 23 Guide 24 Watertight packing retainer 25 Flow Path 26 Aperture 30 Watertight packing 31 Contact plane 32 Base 33 Cylinder section 34 Groove 35 Circular Mouth 40 grooves 41 X Ring (First X Ring) 42 Spring 43 Spring housing 44 Spacer 50 Cylindrical part 51 Groove 52 X-Ring (Second X-Ring) 53 Supply port 54 Water pipe 55 Aperture 56 Strainer H Arrow

Claims

1. A pressure reducing valve having a supply side connection means for connecting to a piping on a water supply side and a discharge side connection means for connecting to another piping or device on a discharge side of the supplied water, A housing having a cylindrical internal space; a cylindrical internal nozzle provided in the internal space of the housing and configured to discharge the supplied water from a tip thereof; a sliding valve including a ring-shaped pressure receiving portion slidably provided along an inner peripheral wall of the housing, a cylindrical guided portion slidably provided along an outer peripheral surface of the inner nozzle, and a water stop packing capable of contacting a tip of the inner nozzle; A spring is provided to press the sliding valve to the discharge side, This pressure reducing valve is characterized in that the sliding valve moves to the supply side when the load received by the pressure-receiving part due to an increase in water pressure exceeds the pressing force of the spring, and abuts a water-stopping gasket against the tip of the internal nozzle to stop the water flow.

2. 3. The pressure reducing valve according to claim 2, characterized in that an X-ring is attached to a sliding contact portion of a circular pressure-receiving portion that is in sliding contact with an inner peripheral wall of a cylinder formed as an internal space of the housing, and to an outer peripheral surface of the internal nozzle that is in sliding contact with an inner peripheral surface of the guided portion, and the X-ring is configured to maintain airtightness of a spring accommodating chamber that accommodates the spring.

3. The cylinder has an inner surface provided with a contact surface against which an annular flat surface provided on a sliding contact portion of the sliding valve comes into contact, 3. The pressure reducing valve according to claim 2, characterized in that a conical inclined surface is provided at the boundary between the abutment surface and a pipe portion communicating with a water discharge port, thereby exposing an inner peripheral portion of the annular plane to the water flow flowing through the pipe portion.

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