JP2018180704A - Pressure reduction valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a pressure reduction valve that has an improved flow volume performance by decreasing a pressure loss in a flow path.SOLUTION: A pressure reduction valve 20 includes: an inlet port 36 provided at a primary-side water area that has a primary pressure; an outlet port 37 provided at a secondary-side water area that has a secondary pressure lower than the primary pressure; and a valve mechanism which has a cutoff function, and provided at a boundary area 39 between the primary-side water area and the secondary-side water area. A flow path shape from the boundary area 39 to the outlet port 37 located below the valve mechanism is formed in a semi-teardrop streamline shape that smoothly changes toward the outlet port 37.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a pressure reducing valve, and, for example, to a pressure reducing valve used for a water heater.

Conventionally, among pressure reducing valves used for heat pump water heaters for detached houses, a pressure reducing valve provided with a valve mechanism having a water blocking function that variably adjusts the flow path area at the boundary between the primary side water area and the secondary side water area Are known. The pressure reducing valve has the function of reducing the primary water pressure supplied from the Water Works Bureau to the secondary water pressure of household use water pressure, the flow passage area at the boundary between the primary water area and the secondary water area, and the primary pressure at the boundary. And the function of determining the flow rate supplied to the secondary side from the difference between the pressure on the secondary side and the pressure on the secondary side.
In recent years, it is necessary to reduce the size of the pressure reducing valve in order to reduce the mounting area along with the increase in the tank capacity of the heat pump water heater and to reduce the cost.

Conventionally, a pressure reducing valve having a piston inclination preventing mechanism that can be applied to a pressure reducing valve having a configuration in which a valve inlet and a valve outlet are orthogonal to each other without increasing the size of the pressure reducing valve has been disclosed (for example, patent documents 1).
The pressure reducing valve is a pressure reducing valve having a water blocking function for variably adjusting the flow area of the boundary portion between the primary side flow path and the secondary side flow path, and is slidably inserted into the cylinder and the central axis of the cylinder And a first piston rod coaxially extending from one end of the cylinder and projecting outward from one end of the cylinder, and a second piston projecting from the other end of the piston head out of the cylinder And a rod. The pressure reducing valve is disposed coaxially with the cylindrical valve seat at one end of the cylinder, the valve body projecting and fixed to the outside of the cylinder of the first piston rod, and separated from the piston head of the second piston rod And a mechanism for guiding the second piston rod in the direction of the central axis of the cylinder.

JP, 2015-141558, A

The pressure reducing valve needs to be downsized in recent years because it is required to reduce the mounting area and the cost reduction due to the increase of the tank capacity of the heat pump water heater, but the hot water supply and water supply capacity are equal to or more than conventional Is required. Therefore, it is necessary to secure the flow rate equal to or higher than the conventional flow rate (hereinafter referred to as flow rate performance).
In order to miniaturize the pressure reducing valve and ensure the flow rate performance, it is necessary to maintain the flow path cross-sectional area and store other mechanical components while securing the thickness of the pressure reducing valve structural component to ensure the strength against the working water pressure. is there.
However, in the conventional pressure reducing valve, there is a problem that it is very difficult to satisfy the demand for securing the flow rate performance as the size is reduced.

  The present invention has been made to solve the problems as described above, and it is an object of the present invention to provide a pressure reducing valve with improved flow rate performance by reducing the pressure loss in the flow path of the pressure reducing valve. ing.

The pressure reducing valve according to the present invention comprises an inlet provided in a primary water area having a primary pressure, an outlet provided in a secondary water area having a secondary pressure lower than the primary pressure, and a water blocking function. A valve mechanism provided in a boundary area between the primary side water area and the secondary side water area, and a flow path shape from the boundary area located below the valve mechanism to the outflow port is It is formed in the shape of a semi-tear drop shape which changes smoothly toward the outlet.

  According to the pressure reducing valve according to the present invention, the flow path shape from the lower boundary region of the valve mechanism to the outlet is formed into a streamline of a semi-droplet shape which changes smoothly toward the outlet, The pressure loss generated in the flow path can be reduced, and the flow rate performance can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is a system figure of the water heater by which the pressure-reduction valve which concerns on Embodiment 1 of this invention was mounted. It is a longitudinal cross-sectional view of the pressure-reduction valve which concerns on Embodiment 1 of this invention. It is a longitudinal cross-sectional view of the pressure-reduction valve which concerns on Embodiment 2 of this invention.

Embodiment 1
Hereinafter, Embodiment 1 of the present invention will be described based on the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.
FIG. 1 is a system diagram of a water heater on which a pressure reducing valve according to Embodiment 1 of the present invention is mounted. FIG. 2 is a longitudinal cross-sectional view of the pressure reducing valve according to the first embodiment of the present invention.
(About the configuration)
As shown in FIG. 1, the water heater 1 converts the water of normal temperature into hot water by exchanging heat with heat exchangers (not shown) provided in the water heater 1 and in the outdoor unit 2 to convert the water into a kitchen or a bath. It is a device that supplies to places. The pressure reducing valve 5 is provided as a part of the piping 8 of the water heater 1, and provided to reduce the primary pressure of the high pressure water 6 supplied from the water service station to the secondary pressure of the household low pressure water 7 .

In general, the pressure reducing valve 5 is connected directly to or near a pipe 8 through which water at the primary pressure passes. The reason for arranging the pressure reducing valve 5 at such a position is to supply the water reduced to the secondary pressure to the tank 3 and the mixing valve 4 so that the pressure resistance standard of the piping 8 and the tank 3 after the pressure reducing valve 5 is primary. This is because the differential pressure between the pressure and the secondary pressure can be reduced, and simplification of piping design and cost reduction become possible.
From the above-described piping configuration, the pressure reducing valve 5 is required to have a pressure resistant design at the primary pressure, and the supply of water to piping components such as the tank 3 after the pressure reducing valve 5 and the mixing valve 4 is required.

FIG. 2 is a longitudinal cross-sectional view of the pressure reducing valve according to Embodiment 1 of the present invention. The pressure reducing valve 20 is constituted by a body 30, a spring cover 21, and a lower cover 34. The body 30 and the spring cover 21 may be formed by machining metal, but may be formed by injection molding in order to reduce the manufacturing cost. In the injection molding method, a thermoplastic resin material, particularly one obtained by adding 10 to 40% of glass fiber to polyphenylene sulfide (hereinafter, referred to as PPS + GF 10 to 40%) may be used.
As shown in FIG. 2, cylindrical shaped inlets 36 and outlets 37 are provided at both ends of the body 30, and the inlets 36 and outlets 37 are coaxially arranged.

Further, in the body 30, a boundary portion 39, which is a part of the valve mechanism part, between the primary side water area on the inlet 36 side and the secondary side water area on the outlet 37 side is provided in a cylindrical shape. The boundary 39 is formed of resin. In addition, the piston 27 which is part of the valve mechanism component coaxially with the cylindrical shape of the boundary portion 39 and which reciprocates in the vertical direction 41 according to the pressure difference between the primary side water area and the secondary side water area. And a cylindrical sliding portion 46 in which a piston O-ring 29 for partitioning the primary side water area and the secondary side water area is inserted.
Furthermore, a diaphragm 26 for separating the secondary side water area and the outside is fitted into the fitting portion with the spring cover 21 at the upper end of the body 30, and the outer periphery of the diaphragm 26 is compressed with the spring cover 21 and the body 30 to form watertightness. A groove is provided in a cylindrical shape to secure the
Further, at the lower end portion of the body 30, a cylindrical hole is provided in order to enable assembly from the vertical direction 41 when assembling the components of the pressure reducing valve 20. Furthermore, in the hole at the lower end portion of the body 30, insertion of the lower lid 34 and watertightness in the lower lid O-ring 35 are secured in order to separate the secondary side water area and the outside.

The diaphragm 26 is a part of the valve mechanism component, and reciprocates in the vertical direction 41 when fluid flows in the pressure reducing valve 20. Therefore, the diaphragm 26 is resistant to pressure from the secondary side water area and repetitive operation. It is necessary to ensure the strength and the resistance to the fluid in contact. Therefore, a rubber material is used as the material of the diaphragm 26 in order to ensure chlorine resistance and water tightness with other parts in a base fabric material in which fibers such as polyester are woven. The rubbery material may be fluorine-based rubber such as EPDM (ethylene-propylene rubber), FKM or the like.
The spring cover 21 includes a coil spring 24 which is a part of a valve mechanism part, a spring storage case 25 for transmitting the pressure in the secondary side water area in the pressure sensing chamber 38 received by the diaphragm 26 to the coil spring 24; The adjustment screw 22 which determines the upper limit (hereinafter referred to as a setting pressure) of the pressure in the water area by adjusting the amount of compression of the coil spring 24, and the spring retainer 23 transmitting the forces of the coil spring 24 and the adjustment screw 22 to both .

The spring cover 21 is machined with a female screw, and an adjusting screw 22 with a male screw is disposed on the female screw. The male and female threads may have a fine pitch thread shape such as fine in order to improve adjustment accuracy.
The pressure reducing valve 20 is fixed by screwing to the body 30 from the side of the spring cover 21 and is further screwed to the body 30 from the side of the lower lid 34 to complete the outer shell.
Further, the diaphragm 26 is tightened together with the upper screw 28 in the order of the diaphragm 26 and the spring storage case 25 on the upper end side of the piston 27 to ensure water tightness. A rubber disc 31 is inserted into the lower end of the piston 27 to contact the lower end of the boundary 39 when the set pressure is reached, and to separate the primary water area and the secondary water area. In this structure, the disk cover 32 for correcting the shape deformation direction when the disk 31 is compressed is fixed by the lower screw 33 by co-tightening with the piston 27.

(About decompression method)
The pressure reducing valve 20 reduces the pressure by reducing the gap 44 between the valve seat 45 which is the lower end portion of the boundary portion 39 of the body 30 and the disc 31 which is a valve body. The pressure in the gap 44 is that the coil spring 24 pushes the piston 27 in the valve opening direction 42, the pressure in the primary water area pushes the piston 27 and the disk 31 in the valve opening direction 42, and the pressure in the secondary water area The force of pushing the diaphragm 26 in the valve closing direction 43 in the chamber 38 and the pressure of the secondary side water area are determined by the balance of the force pushing the disc cover 32 in the valve closing direction 43.
The pressure reducing valve 20 is mainly disposed in the vicinity of the connection portion with the primary water pressure piping 8 of a device requiring a pressure reducing function such as the water heater 1, and a water discharging device (not shown) such as a faucet of water is closed. When the fluid in the flow path on the secondary side water area side of the pressure reducing valve 20 is stopped, the pressure reducing valve 20 is closed.

For example, when a water discharge device (not shown) such as a tap of water supply is opened and the fluid in the flow path on the secondary side water area side moves further to the water discharge device side located on the secondary side, the secondary side water area of the pressure reducing valve 20 Pressure is reduced. As a result, since the pressure reducing valve 20 is closed by the pressure in the valve closing direction 43 due to the set pressure, the pressing force in the valve closing direction 43 due to the pressure in the secondary side water area becomes small. The valve is opened when the pressing force is greater, and the fluid flows from the primary water area to the secondary water area.
For example, when a water discharge device (not shown) such as a tap of water is closed, the flow velocity of the fluid approaches zero, and when the pressure in the secondary side water area increases, the diaphragm 26 of the pressure sensing chamber 38 is pushed in the valve closing direction 43 The force increases, the valve mechanism moves in the valve closing direction 43, and the gap 44 becomes smaller. Furthermore, the pressure loss as the fluid passes through the boundary 39 and the secondary water near the boundary 39 is increased. As a result, the pressure reaches the set pressure of the pressure reducing valve 20, and the pressing force in the valve closing direction 43 is larger than the pressing force in the valve opening direction 42, and the pressure reducing valve 20 closes.

As in the pressure reducing valve 20 according to the first embodiment of the present invention, the inlet 36 of the primary water area and the outlet 37 of the secondary water area are coaxial with each other, and the primary water area and the secondary water area are bounded. In the pressure reducing valve structure in which the gap 44 between the boundary 39 and the disk 31 is controlled by the balance between the coil spring 24 and the primary side water area and the secondary side water balance by pressure balance control. The flow velocity of the fluid flowing from the primary side water area to the secondary side water area in the space 44 between the disc 31 and the disc 31 is the highest, and the pressure loss generated in the space 44 is also the largest.
In the first embodiment of the present invention, paying attention to the above-described event, the flow path of the lower lid 34 located under the boundary 39 where the flow rate in the pressure reducing valve 20 is fast and the generation ratio of pressure loss in the pressure reducing valve 20 is large. The wall 40 (flow path shape) is formed in the flow path of the secondary water area when the pressure reducing valve 20 is opened by making the wall 40 (flow path shape) smooth and have a half teardrop shape along the outlet 37 of the secondary water area. Pressure loss can be reduced. As a result, the flow rate can be increased accordingly.

Second Embodiment
FIG. 3 is a longitudinal sectional view of a pressure reducing valve according to Embodiment 2 of the present invention. The pressure reducing valve 50 according to the second embodiment of the present invention will be described below with reference to FIG.
(About the configuration)
In the second embodiment, only the shapes of the flow path wall 40 of the body 30, the lower lid 34, and the lower lid 34 of the pressure reducing valve 20 of the first embodiment are different from those of the first embodiment. It is the same. Therefore, in the second embodiment, the body 51 and the flow channel wall 53 of the lower lid 52 which are modified from the first embodiment will be described with reference to FIG. The description of other structures will be omitted by using the same reference numerals as in the first embodiment.

  As shown in FIG. 3, the body 51 is provided with cylindrical inlets 36 and outlets 37 at both ends, and the inlets 36 and the outlets 37 are coaxially arranged. Further, in the body 51, a boundary 39 between the primary side water area on the inlet 36 side and the secondary side water area on the outlet 37 side, which is a part of the valve mechanism part, is provided in a cylindrical shape. A piston 27 that reciprocates in the vertical direction 41 according to the pressure difference between the primary side water area and the secondary side water area with a part of the valve mechanism part coaxially with a cylindrical shape, and a piston that divides the primary side water area and the secondary side water area A cylindrical sliding portion 46 into which the O-ring 29 is inserted is provided. Below the boundary 39, a cylindrical hole is provided to allow assembly from the vertical direction 41 when assembling the components of the pressure reducing valve 50, and the hole at the lower end of the body 51 is a secondary In order to separate the side water area and the outside, the insertion of the lower lid 52 and the watertightness in the lower lid O-ring 35 are secured.

A rubber disc 31 is inserted into the lower end of the piston 27 to contact the lower end of the boundary 39 when the set pressure is reached, and which separates the primary water area and the secondary water area. In this structure, the disk cover 32 for correcting the shape deformation direction when the disk 31 is compressed is fixed by the lower screw 33 by co-tightening with the piston 27.
The assemblability with the spring cover 21 and the valve mechanism parts assembled to the upper portion of the other body 51 and the watertight structure are the same as or the same performance as the first embodiment, and thus the description thereof will be omitted.

(About decompression method)
Similar to the pressure reducing valve 20 of the first embodiment, the pressure reducing valve 50 reduces the pressure by reducing the gap 44 between the valve seat 45 which is the lower end portion of the boundary portion 39 of the body 51 and the disc 31 which is a valve body. In the gap 44, the force by which the coil spring 24 pushes the piston 27 in the valve opening direction 42 in the first embodiment, the force by which the pressure in the primary side water area pushes the piston 27 and the disc 31 in the valve opening direction 42, and the secondary side water area 2 is determined by the balance between the force pressing the diaphragm 26 in the valve closing direction 43 in the pressure sensing chamber 38 shown in FIG. 2 and the pressure in the secondary side water zone pushing the disc cover 32 in the valve closing direction 43.

  The pressure reducing valve 50 is disposed in the vicinity of the connection with the primary water pressure piping 8 mainly for an apparatus such as the water heater 1 that requires a pressure reducing function. For example, when the water discharge device (not shown) such as a tap of the water supply is closed and the fluid in the flow passage on the secondary side water area side of the pressure reducing valve 50 is stopped, the pressure reducing valve 50 is closed. For example, when the water discharge device (not shown) such as a tap of water is opened and the fluid in the flow path on the secondary side water area side moves further to the water discharge device located on the secondary side, the secondary side of the pressure reducing valve 50 Water pressure drops. As a result, since the pressure reducing valve 50 is closed by the pressure in the valve closing direction 43 due to the set pressure, the pressing force in the valve closing direction 43 due to the pressure in the secondary side water area decreases and the valve opening direction 42 is pushed When the force increases, the valve opens and fluid flows from the primary water area to the secondary water area.

  For example, when a water discharge device (not shown) such as a tap of water is closed, the flow velocity of the fluid approaches zero, and when the pressure in the secondary side water area increases, the diaphragm 26 of the pressure sensing chamber 38 is pushed in the valve closing direction 43 The force increases, the valve mechanism moves in the valve closing direction 43, and the gap 44 becomes smaller. Furthermore, the pressure loss as the fluid passes through the boundary 39 and the secondary water near the boundary 39 is increased. As a result, the pressure reaches the set pressure of the pressure reducing valve 50, and the pressing force in the valve closing direction 43 is larger than the pressing force in the valve opening direction 42, and the pressure reducing valve 50 closes.

  In the pressure reducing valve 50 according to the second embodiment of the present invention, as in the pressure reducing valve 20 according to the first embodiment, the disk is used to reduce the pressure loss that occurs when fluid flows from the primary water area to the secondary water area. 31 and the lower cover 52 provided below the disc cover 32 in the same way as the lower cover 34 of the first embodiment, the flow path wall 53 (flow path shape) of the lower cover 52 is connected to the outlet 37 which is the secondary water area. Smooth along the teardrop-shaped streamline. Furthermore, in the second embodiment, the boundary of the secondary water area is provided by providing a dimple structure in which a plurality of minute depressions 54 are arranged in a semicircular arc shape in the channel wall 53 which is the inner surface of the lower lid 52 on the channel side. The vortices that cause pressure loss around the part 39 are refined, and the vortices are generated from the area around the boundary 39 where the flow velocity is high to the secondary side water area where the flow velocity is relatively low in the flow path of the pressure reducing valve 50 It can be moved to the vicinity of a certain outlet 37. As a result, the pressure loss generated in the pressure reducing valve 50 can be reduced, and the flow rate can be increased accordingly.

The depth and size of the recess 54, the arrangement interval of the recesses, and the number of arrangement differ depending on the viscosity of the fluid and the speed of the fluid in the flow field of the dimple structure. These differ depending on the flow field in the pressure reducing valve 50, the set pressure of the pressure reducing valve 50, and the amount of fluid discharged from the discharge device disposed on the secondary side of the pressure reducing valve 50 and thereafter. Therefore, it is necessary to design according to the environment where the pressure reducing valve 50 is used.
In the present invention, within the scope of the invention, each embodiment can be freely combined, or each embodiment can be appropriately modified or omitted.

  Reference Signs List 1 water heater, 2 outdoor units, 3 tanks, 4 mixing valves, 5 pressure reducing valves, 6 high pressure water supplied from the water service station, 7 household low pressure water, 8 piping, 20 pressure reducing valves, 21 spring covers, 22 adjustment screws , 23 spring retainer, 24 coil spring, 25 spring storage case, 26 diaphragm, 27 piston, 28 upper screw, 29 piston O ring, 30 body, 31 disc, 32 disc cover, 33 lower screw, 34 lower lid, 35 lower cover O-ring for lid, 36 inlet, 37 outlet, 38 pressure sensing chamber, 39 boundary part, 40 channel wall, 41 vertical direction, 42 valve opening direction, 43 valve closing direction, 44 gap, 45 valve seat, 46 slide Moving part, 50 pressure reducing valve, 51 body, 52 lower lid, 53 flow path wall, 54 dent

Claims (4)

An inlet provided in the primary water area having a primary pressure;
An outlet provided in a secondary water area having a secondary pressure lower than the primary pressure;
A valve mechanism having a water stop function and provided in a boundary region between the primary side water area and the secondary side water area;
The pressure reducing valve is characterized in that a flow path shape from the boundary area located below the valve mechanism to the outlet is formed in a streamline shape of a semi-tear drop shape that smoothly changes toward the outlet. .   The pressure reducing valve according to claim 1, wherein a dimple structure is provided in a part of the flow path shape from the boundary area to the outflow port. The valve mechanism includes a valve seat disposed in the boundary area between the primary side water area and the secondary side water area;
A valve body disposed opposite to the valve seat and connected to one end of a piston receiving the primary pressure of the primary side water area;
The pressure reducing valve according to claim 1 or 2, further comprising: a diaphragm connected to the other end of the piston and receiving the secondary pressure of the secondary side water area. The said inflow port provided in the said primary side water area | region and the said outflow port provided in the said secondary side water area were coaxially arrange | positioned, The any one of the Claims 1-3 characterized by the above-mentioned. Pressure reducing valve as described in.

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