JP3040627U - Pressure reducing valve - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To stabilize the set pressure of a pressure reducing valve and improve the flow rate specification. SOLUTION: A valve seat formed at the tip of a partition wall standing upright in a flow path, a main valve arranged to face the valve seat, a diaphragm chamber in the vicinity of the partition wall in which a diaphragm is stretched, and a partition wall A pressure introducing hole that connects the downstream side flow passage on the downstream side and the diaphragm chamber, and a stem that is fixed to the main valve and is movable back and forth in the diaphragm chamber. A pressure reducing valve in which the valve seat is opened and closed by the main valve by the pressure of the diaphragm chamber transmitted through the pressure reducing valve, which is provided with a plurality of pressure introducing holes for communicating the secondary side flow passage and the diaphragm chamber. .

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a pressure reducing valve, and more particularly to a pressure reducing valve having stabilized set pressure and improved flow characteristics.

[0002]

[Prior art]

 An example of a conventional pressure reducing valve will be described with reference to FIG. A valve seat 102 formed at the tip of a partition wall 101 standing in the flow path, a main valve 103 arranged to face the valve seat 102, and a diaphragm chamber 105 in which a diaphragm 104 provided near the partition wall 101 is stretched. A pressure introducing hole 107 that connects the secondary flow passage 106 on the downstream side of the partition wall 101 to the diaphragm chamber 105, and a stem 109 fixed to the main valve 103 and provided in the diaphragm chamber 105 so as to move back and forth. The valve seat 102 is opened and closed by the main valve 103 by the pressure of the diaphragm chamber 105 transmitted from the secondary side flow passage 106 through the pressure introduction hole 107.

The above configuration will be described in more detail. A partition wall 101 having a substantially arcuate shape in a plan view is erected in an intermediate portion of the flow path of the main body 111, and a tip of the partition wall 101 is formed on a valve seat 102. An upstream side of the partition wall 101 is a primary side flow path 112 and a partition wall 101. The downstream side is the secondary side flow passage 106, and the flow passage is formed from the primary side flow passage 112 through the secondary side flow passage 106. A main valve 103 is arranged so as to face the valve seat 102 in order to block or allow the air flowing through this flow path to flow.

The main valve 103 is fixed to the stem 109 by being sandwiched between the step portion 113 and the E ring 114, and is slidably provided on a spring receiver 115 fixed to a lower wall 118 of the main body 111. It is urged by a spring 116 and abuts against the valve seat 102. The upper portion of the stem 109 in the drawing penetrates the upper wall 119 of the main body 111 and is provided in the diaphragm chamber 105 so as to be movable back and forth.

The diaphragm chamber 105 is composed of the upper surface of the upper wall 119 of the main body 111 and the stretched diaphragm 104, and the diaphragm 104 is pressed at its entire peripheral end portion to the upper wall 119 of the main body 111 by the bonnet 117. It is screwed by a bolt 128. The diaphragm 104 is brought into contact with the diaphragm receiver 120 on the upper side of the central portion thereof, and the relief valve seat 121 having the relief hole 108 is inserted into the diaphragm 104 and screwed into the diaphragm receiver 120, and the stem 109 is opened at the opening of the relief hole 108. The upper end of the relief hole 108 is brought into contact so that the opening of the relief hole 108 can be opened and closed.

An adjusting spring 122 for setting a pressure is housed in the bonnet 117, the lower end of which is brought into contact with the upper surface of the diaphragm receiver 120, and the upper end of the adjusting spring 122 is brought into contact with the lower surface of the support plate 123, so that the bonnet The lower end of the adjusting screw 125 of the handle 124 screwed to the upper portion of 117 is brought into contact with the center of the upper surface of the support plate 123, and the adjusting screw 125 is screwed and adjusted to set the pressure applied to the diaphragm 104, and then screwed to the adjusting screw 125. The nut 126 for fixing is screwed and fixed.

Reference numeral 127 is a bleed that releases the air in the bonnet 117 to the atmosphere. The set pressure is set by introducing air at the set pressure into the diaphragm chamber 105, rotating the handle 124 to appropriately compress the adjusting spring 122, and applying a spring force to the diaphragm 104 to close the main valve 103. Air pressure in the secondary side flow passage 106 acts on the lower surface of the diaphragm 104.

When the pressure in the secondary side flow passage 106 becomes higher than the set pressure, the diaphragm 104 is pushed up, the relief valve seat 121 also moves upward, and the relief valve seat 121 and the stem 109 are separated from each other, and the secondary side flow The increased pressure in the passage 106 flows into the bonnet 117 from the relief hole 108 of the relief valve seat 121, flows out through the bleed 127 of the bonnet 117 into the atmosphere, and does not exceed the set pressure.

When the air in the secondary side flow passage 106 is consumed due to the operation of the pneumatic cylinder or the like, the pressure in the secondary side flow passage 106 drops, the pressure in the diaphragm chamber 105 also drops, and the diaphragm 104 Moves downward to move the stem 109 and the main valve 103 downward, the valve seat 102 is opened, and air is supplied from the primary side flow passage 112 to the secondary side flow passage 106 until consumption stops.

Normally, the pressure introduction hole 107 of the pressure reducing valve stabilizes the set pressure by transmitting the fluctuation of the secondary side flow passage 106 to the diaphragm chamber 105 with a time delay and opening / closing the main valve 103.

[0011]

[Problems to be solved by the device]

 Normally, as shown in Fig. 4, the flow rate characteristics of the pressure reducing valve are such that in the maximum flow rate range of each main valve, the air in the secondary side flow path is close to the speed of sound, so that the siphon effect is excessive in the pressure introduction hole. Effectively, the pressure in the diaphragm chamber is pulled by the secondary side flow passage and decreases conversely. Therefore, a phenomenon called overshooting, which is usually called overshoot, occurs in the maximum flow rate region of the set pressures, especially in the low pressure setting.

There is a method of reducing the diameter of the pressure introducing hole to prevent overshoot, but the timing of feeding back the air pressure in the secondary side flow path to the main valve is disturbed to promote oscillation of the main valve, or Moreover, there is a problem that the pressure drop becomes severe in the maximum flow rate range.

[0013]

[Means for Solving the Problems]

 Therefore, in view of the above circumstances, the present invention is designed to stabilize the set pressure and improve the flow rate characteristics, and a valve seat formed at the tip of the partition wall standing in the flow path and a main valve disposed opposite to the valve seat. The valve, a diaphragm chamber with a diaphragm installed near the partition, a pressure introducing hole that connects the secondary side flow path downstream of the partition with the diaphragm chamber, and the diaphragm chamber fixed to the main valve. In the pressure reducing valve, which is composed of a stem that can be advanced and retracted and is configured to open and close the valve seat with the main valve by the pressure of the diaphragm chamber transmitted from the secondary side flow path through the pressure introduction hole, The pressure reducing valve is provided with a plurality of pressure introducing holes that connect the flow passage and the diaphragm chamber.

The pressure fluctuation is made as flat as possible by connecting the secondary side flow passage and the diaphragm chamber with each other through a plurality of pressure introducing holes. Further, the present invention has two pressure introducing holes in order to make production as easy as possible. Further, in the present invention, the pressure introducing holes are provided at the upstream side and the downstream side, which are susceptible to the fluctuation of the pressure of the secondary side flow passage, and at each one position. The upstream pressure introducing hole takes charge of filling the pressure in the diaphragm chamber, and the downstream pressure introducing hole takes charge of pressure outflow from the diaphragm chamber to the secondary side flow passage to flatten the pressure fluctuation.

Furthermore, the upstream pressure introducing hole of the present invention is provided in the wall body that divides the secondary side flow passage and the diaphragm chamber by inclining to the upstream side by 45 ° with respect to the thickness direction of the wall body. As a result, the air passage distance is increased, and the pressure fluctuation is flattened in the direction opposite to the direction in which the air passes through the secondary flow path.

[0016]

[Embodiment of the invention]

 The present invention will be described in detail below based on specific embodiments shown in the accompanying drawings. The pressure reducing valve of the present invention will be described with reference to FIG. A valve seat 2 formed at the tip of a partition wall 1 standing in the flow path, a main valve 3 arranged to face the valve seat 2, and a diaphragm chamber 5 in which a diaphragm 4 provided near the partition wall 1 is stretched. The pressure inlet hole 7 that connects the secondary flow path 6 downstream of the partition wall 1 to the diaphragm chamber 5 and the stem 9 that is fixed to the main valve 3 and that is movable back and forth in the diaphragm chamber 5. Then, the valve seat 2 is opened and closed by the main valve 3 by the pressure of the diaphragm chamber 5 transmitted from the secondary side flow path 6 through the pressure introduction hole 7.

The above configuration will be described in more detail. A partition wall 1 having a substantially arcuate shape in a plan view is erected at an intermediate portion of the flow path of the main body 1, and a tip of the partition wall 1 is formed on a valve seat 2. An upstream side of the partition wall 1 includes a primary side flow path 12 and a partition wall 1. The downstream side is the secondary side flow path 6, and the flow path is formed from the primary side flow path 12 through the secondary side flow path 6. A main valve 3 is arranged opposite to the valve seat 2 in order to block or allow the air flowing through this flow path to pass.

The main valve 3 is fixed to the stem 9 by being sandwiched between the step portion 13 and the E ring 14, and is slidably provided on a spring receiver 15 fixed to a lower wall 18 of the main body 11. The valve seat 2 is urged by 16 to be in contact with the valve seat 2. The upper portion of the stem 9 in the drawing penetrates the upper wall 19 of the main body 11 and is provided in the diaphragm chamber 5 so as to be movable back and forth.

The diaphragm chamber 5 is composed of the upper surface of the upper wall 19 of the main body 11 and the diaphragm 4 stretched. The diaphragm 4 is pressed at its entire peripheral end portion by the bonnet 17 to the upper wall 19 of the main body 11 and bolts. It is screwed by 28. The diaphragm 4 is brought into contact with the diaphragm receiver 20 on the upper side of the central portion thereof, the relief valve seat 21 having the relief hole 8 is inserted into the diaphragm 4 and screwed into the diaphragm receiver 20, and the stem of the relief hole 8 is opened. The upper end of 9 is brought into contact so that the opening of the relief hole 8 can be opened and closed.

An adjustment spring 22 for setting pressure is housed in the bonnet 17, the lower end of which is brought into contact with the upper surface of the diaphragm receiver 20, and the upper end of the adjustment spring 22 is brought into contact with the lower surface of the support plate 23. The lower end of the adjusting screw 25 of the handle 24 screwed onto the upper part of the bonnet 17 is brought into contact with the center of the upper surface of the support plate 23, and the adjusting screw 25 is screwed and adjusted to set the pressure applied to the diaphragm 4, and then the adjusting screw 25 is screwed. It is fixed by screwing it with the attached fixing nut 26.

Reference numeral 27 is a bleed that releases the air in the bonnet 17 to the atmosphere. The set pressure is set by introducing air of the set pressure into the diaphragm chamber 5, turning the handle 24 to appropriately compress the adjusting spring 22 and applying a spring force to the diaphragm 4 to close the main valve 3. Air pressure in the secondary side flow passage 6 acts on the lower surface of the diaphragm 4.

When the pressure in the secondary side flow passage 6 becomes higher than the set pressure, the diaphragm 4 is pushed up, the relief valve seat 21 also moves upward, the relief valve seat 21 and the stem 9 are separated, and the secondary side flow passage The increased pressure of 6 flows into the bonnet 17 from the relief hole 8 of the relief valve seat 21, flows out to the atmosphere through the bleed 27 of the bonnet 17, and does not exceed the set pressure.

When the air in the secondary side flow passage 6 is consumed by the operation of the pneumatic cylinder, the pressure in the secondary side flow passage 6 drops, the pressure in the diaphragm chamber 5 also drops, and the diaphragm 4 By moving downward, the stem 9 and the main valve 3 are moved downward, the valve seat 2 is opened, and air is supplied from the primary side flow passage 12 to the secondary side flow passage 6 until consumption is stopped. In the present invention, the secondary side flow path 6 and the diaphragm chamber 5 are communicated with each other through a plurality of pressure introducing holes to flatten the pressure fluctuation as much as possible.

Further, the present invention has two pressure introducing holes in order to make production as easy as possible. Further, in the present invention, the pressure introduction holes are provided at one location on each of the upstream side and the downstream side, which are susceptible to the fluctuation of the pressure of the secondary side flow path 6. The upstream side pressure introducing hole 31 is responsible for pressure filling of the diaphragm chamber 5, and the downstream side pressure introducing hole 7 is responsible for pressure outflow from the diaphragm chamber 5 to the secondary side flow passage 6 to flatten the pressure fluctuation.

Furthermore, according to the present invention, the upstream side pressure introducing hole 31 is formed in the upper wall 19 which divides the secondary side flow path 6 and the diaphragm chamber 5 into 45 in the thickness direction of the upper wall 19. Inclining to the upstream side to increase the air passage distance and flatten pressure fluctuations in the direction opposite to the direction in which the air passes through the secondary flow path 6. In addition, the upstream pressure introducing hole 31 can be machined easily in the 45 ° direction.

FIG. 2 shows the flow rate characteristics of the conventional pressure reducing valve and the pressure reducing valve of the present invention. The horizontal axis represents the flow rate and the vertical axis represents the pressure in the relationship between the flow rate and the pressure in the secondary side flow path 6. Set pressure is 1 kgf / cm ^Two The conventional pressure reducing valve is indicated by a black circle and the pressure reducing valve of the present invention is indicated by a square. With the conventional pressure reducing valve, the flow rate increases slightly at first, but it immediately increases, exceeds the set pressure, and the phenomenon of overshoot appears, with a maximum of 1.7 kgf / cm.^Two Also reaches.

On the other hand, in the pressure reducing valve of the present invention, the pressure slightly decreases as the flow rate increases, and a slight overshoot phenomenon appears in the maximum flow rate region, and the maximum value is about 1.1 kgf / cm ² . The set pressure is stabilized and the flow rate characteristics are improved. Although the direct-acting type pressure reducing valve has been described above, the pilot type pressure reducing valve can be applied in exactly the same manner.

[0028]

[Effect of the invention]

 As described above, the present invention has a valve seat formed at the tip of a partition wall standing upright in the flow path, a main valve arranged to face the valve seat, and a diaphragm provided near the partition wall. It consists of an ear chamber, a pressure introducing hole that connects the secondary flow path downstream of the partition wall to the diaphragm chamber, and a stem that is fixed to the main valve and is movable back and forth in the diaphragm chamber. In a pressure reducing valve in which the valve seat is opened and closed by the main valve by the pressure of the diaphragm chamber transmitted from the flow passage through the pressure introduction hole, a plurality of pressure introduction holes that connect the secondary side flow passage and the diaphragm chamber are provided. Since the pressure reducing valve is provided, pressure fluctuation can be made as flat as possible.

Further, in the present invention, since the pressure introducing holes are provided at two places, the manufacturing can be made as easy as possible. Further, in the present invention, since the pressure introducing holes are provided at the upstream side and the downstream side, respectively, of the secondary side flow passage, the upstream side pressure introducing hole takes charge of pressure filling the diaphragm chamber, and the downstream side pressure introducing hole. Takes charge of the pressure outflow from the diaphragm chamber to the secondary side flow path and flattens the pressure fluctuation.

Furthermore, the upstream pressure introducing hole of the present invention is provided in the wall body that divides the secondary flow path and the diaphragm chamber by inclining it to the upstream side by 45 ° with respect to the thickness direction of the wall body. As a result, the air passage distance can be increased and the pressure fluctuation can be flattened in the direction opposite to the direction in which the air passes through the secondary flow path. Further, the drilling of the upstream pressure introducing hole in the 45 ° direction is easy to machine.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a specific embodiment of a pressure reducing valve of the present invention.

FIG. 2 is a graph comparing the flow rate characteristics of the present invention and a conventional pressure reducing valve.

FIG. 3 is a vertical cross-sectional view of a conventional pressure reducing valve.

FIG. 4 is a graph showing a pressure / flow rate characteristic diagram of a conventional pressure reducing valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Partition wall 2 ... Valve seat 3 ... Main valve 4 ... Diaphragm 5 ... Diaphragm chamber 6 ... Secondary side flow passage 7 ... Downstream pressure introduction hole 8 ... Relief hole 9 ... Stem 11 ... Main body 12 ... Primary side flow passage 13 ... Step portion 14 ... E ring 15 ... Spring receiver 16 ... Main valve spring 17 ... Bonnet 18 ... Lower wall 19 ... Upper wall 20 ... Diaphragm receiver 21 ... Relief valve seat 22 ... Adjusting spring 23 ... Support plate 24 ... Handle 25 ... Adjusting screw 26 ... Fixing nut 27 ... Bleed 28 ... Bolt 31 ... Upstream pressure introducing hole

Claims (4)

[Utility model registration claims] 1. A valve seat formed at the tip of a partition wall standing upright in a flow path, a main valve arranged so as to face the valve seat, a diaphragm chamber provided with a diaphragm provided near the partition wall, and a partition wall. A pressure introducing hole that connects the secondary side flow passage on the more downstream side and the diaphragm chamber, and a stem that is fixed to the main valve and is capable of advancing and retracting in the diaphragm chamber. A pressure reducing valve in which the valve seat is opened and closed by a main valve by the pressure of the diaphragm chamber transmitted through the pressure reducing valve having a plurality of pressure introducing holes for communicating the secondary side flow passage and the diaphragm chamber. 2. The pressure reducing valve according to claim 1, wherein there are two pressure introducing holes. 3. The pressure reducing valve according to claim 1, wherein one pressure introduction hole is provided on each of the upstream side and the downstream side of the secondary side flow passage. 4. The pressure reducing valve according to claim 3, wherein the upstream pressure introducing hole is inclined by 45 ° upstream with respect to the thickness direction of the wall body in the wall body that divides the secondary side flow passage and the diaphragm chamber. .