JPS60263786A - Pressure switch device of reducing valve - Google Patents

Abstract

PURPOSE:To prevent a leakage of water in the night by opening a valve body of a differential pressure reducing valve with pressure on primary side to feed water. CONSTITUTION:When the water pressure on secondary side increases, a valve body 21 of pilot valves 21 is lifted up and maintained in the state of closing a valve seat 17. Accordingly, water admitted through a small hole 8 from primary side into a cylinder portion 6 is caught therein, so that a valve body 7 is subjected to downward force and kept in the close state. When the water pressure on secondary side decreases, the valve body 21 is lowered by force of a spring 20. As a hollow portion 41 is closed, the water pressure in the cylinder portion 6 is caught therein, so that the valve body 7 of the differential pressure reducing valve 1 is kept in the close state as before.

Description

[Detailed description of the invention] Technical field of invention The present invention relates to a pressure switching device for a pressure reducing valve.

Technical background of the invention and its problems Conventionally, the valve seat of the differential pressure reducing valve is opened and closed using the differential pressure generated by the pylon 1-valve, which operates by detecting the secondary pressure of the differential pressure reducing valve, thereby maintaining a constant pressure. Some systems exist that supply water to the secondary side until the However, there is a large difference in water demand during the day and at night. Therefore, even though the demand for water is low at night, high pressure acts, causing major leaks.

For this reason, there is an idea described in Japanese Patent Application No. 139500/1983 to achieve the purpose of preventing water leakage at night. This nine is equipped with a valve having a rod connected to the valve body of the differential pressure reducing valve, and the valve is operated by sliding the valve stem in accordance with the movement of the valve body of the differential pressure reducing valve, which operates according to demand. By switching this valve, the water supply is placed under the control of the high-pressure pilot valve or the low-pressure pilot valve, but the valve body of the valve is sensitive to the operation of the valve body of the differential pressure reducing valve. The valves are switched in small increments.

Therefore, although the initial purpose is achieved, since the set pressure of the water supply changes little by little, a water hammer phenomenon acts on the pipe line receiving the water supply, shortening the life of the valve and the pipe line. Even when the water supply record is recorded using the electromagnetic flow rate record 81 or the like, it is difficult to read because the water supply amount changes little by little.

Purpose of invention This invention was made in view of these points.

Prevent tree leakage at night by supplying water according to demand
Moreover, the purpose is to develop a pressure switching device for a pressure reducing valve that can improve the durability of the valve and the pipe line.

Summary of the Invention This invention provides: - A differential pressure reducing valve in which a valve element for opening and closing a valve seat between an upstream side and a secondary side is slidably held in a cylinder part, and communicates with the cylinder part. A high-pressure pylon 1-valve and a low-pressure pylon 1-valve that open and close according to changes in secondary pressure are provided, and a valve having nine valve stems connected to the valve body of the differential pressure reducing valve is provided.

When the pressure on the secondary side is low, the cylinder part is communicated with the secondary side via high pressure or low pressure pilot force, and thereby the valve element of the differential pressure reducing unit is opened by the pressure on the primary side and water is supplied. When the pressure on the secondary side reaches the set pressure or higher, close the high pressure or low pressure pilot valve and close the valve body of the differential pressure reducing valve to reduce the secondary pressure between the high pressure pylon 1~valve and the low pressure pilot valve. By changing the opposing set pressure, during the daytime when demand is high, the valve of the differential pressure reducing valve is operated by a large opening action of the valve body and placed under the control of the high pressure pilot valve, and during the night when demand is low, the valve is switched. The operation blocks the flow path from the cylinder section to the high-pressure pilot valve and places it under the control of the low-pressure pilot valve. Therefore, a small amount of water is supplied at night to prevent water leakage, and the valve body of the differential pressure reducing valve By connecting the valve body and the valve body with some play so that they can slide slightly in the axial direction, the phenomenon of the valve switching in small steps can be prevented, and therefore the set pressure can be adjusted in small steps. The structure was designed to prevent the valves and pipes from becoming damaged and increase the durability of the valves and pipelines.

Examples of the invention An embodiment of the present invention will be described based on the drawings.

1 is a pressure valve (differential pressure type), and its valve box 2 has an opening 11 on the primary side.
3, a secondary side opening 14, a valve seat 5, and a cylinder part 6 located above the valve seat 5, and the cylinder part 6 has a valve whose diameter is larger than that of the lower part. The body 7 is provided so that it can be moved freely. Further, the valve body 7 is provided in the valve box 2.
A tapered needle 9 inserted into a pore 8 formed in the center of
has been erected.

Then, the high pressure pilot valve 10 and the low pressure pylon 1-ga,
11 are provided. The structure of both is the same.
・Describe the method. That is, as shown in FIG. 2, a valve box 2 is provided. This valve box 12 has a pipe 13
．． 14, a communication port 15 connected to the secondary side of the differential pressure reducing valve 1, and a connection I connected to the cylinder portion 6.
16 and the valve seat communicating between them] 7 & pressure receiving chamber I
8 is formed. Further, this valve box 12 houses a pressure setting spring 20 whose one end is connected to a spring receiver 19, and a valve body 21.The valve body 21 has a pressure receiving fitting 2 and 3 attached to a valve stem 22. A bellows lam 24, a collar 25, a bellows 1126, and a spring receiver 27 are inserted and fixed in a laminated state into this pressure receiving metal fitting 23. These bellofram 24
．． The outer periphery of the valve body 26 is held between the body shaft 28 and a lower lid 29 and an upper lid 30, respectively, which constitute the valve box 12. A detection body 31 is attached to the valve box 12. This detection body 31 is fitted with a cylinder 32 communicated between the belloframs 24 and 26, a detection rod 33 that rises due to an increase in the internal pressure of this cylinder 32, and two parts of the cylinder 32. The detection rod 33 is surrounded by a transparent tube 34.

Next, a valve 35 is provided at the top of the valve box 2. That is, an outer cylinder 38, which is provided with two connection ports 36 and 37 with a high pressure difference on the outer periphery, is screwed into the second part of the street box 2 while being sealed.

A switching rod 39 is inserted into this outer cylinder 38.
A part of the arm 9 is screwed into the upper part of the outer cylinder 38, and an operating part 40 is formed at the -11 part. This switching rod 39 has a hollow portion 41 that is open at the lower end. Further, an annular passage 42 communicating with the connection port body 36 is formed in the center of the inner periphery of the outer cylinder 38, and this passage 42 communicates with the hollow portion 41 through a through hole 43. Furthermore, the outer cylinder 3
An annular passage 44 is formed at the lower part of the inner periphery of the connecting body 8 to communicate the connecting body 37 with the cylinder portion 6.

A valve rod 46 having a seal portion 45 with a large diameter is inserted into the hollow portion 41 so as to be relatively movable. At the lower end of this valve stem 46, a flange 50 and a nut 51 are provided which face each other below the expanded portion 7a of the valve body 7. Part 7a
The valve body 7 and the valve stem 46 can be slid relative to each other with a play of h. Further, an o-ring retainer 53 for fixing an O-ring 52 is screwed onto the upper part of the switching rod 39. This O-ring 52 applies a certain sliding resistance to the valve body 46. Thus, the connection port 16 of the high pressure pilot valve 10 is connected to the connection 1" body 36 by a pipe 48, and the low pressure pylon 1-valve 11
The connection port 16 is connected to the connection port body 37 by a pipe 49 and is constantly connected to the cylinder portion 6 via the passage 44.

In such a configuration, for example, the force of the pressure setting spring 20 of the valve 10 on the high-pressure pilot 1 is set to a force that opposes a water pressure of 3 kg/cm, and that of the low-pressure pilot valve 11 is set to a force that opposes a water pressure of 1 kg/cm.
kt ! : The pressure setting is performed by changing the set height of the spring 20.

Therefore, the water pressure on the secondary side acts on the pressure receiving chamber 18 of the high-pressure and low-pressure pilot valve 10, ]1 via the pipe 13.14. Now, if the water pressure on the secondary side is slightly over 3 kg/cm, which pylon 1 to valve 10.1
1, the valve body 21 is maintained in a state in which the two parts close the seat 17. Therefore, the water that reaches the cylinder part 6 from the next side through the pores 8 has no place to escape, and the valve body 7 is subjected to a downward force because the negative surface has the largest pressure receiving area, and the valve body 7 is shown in FIG. so that it remains closed. The valve body 46 is also located in the lowered position and closes the lower end of the hollow part 41 with the sealing part 45.9 If the water pressure on the secondary side exceeds even slightly more than 3 cm/cJ, the high pressure pylon 1-valve 10 closes the lower end of the hollow part 41. 21 opens to lower F by the force of the setting spring 20, but the hollow part 41
Since the lower end is closed 11-, there is no escape for the water pressure in the cylinder portion 6, and the Ji body 7 of the differential pressure reducing valve 1 remains closed. Therefore, if there is demand, the water pressure on the downstream side will continue to decrease, and the water pressure on the secondary side will decrease to 1 kg/c.
When the pressure drops below nt, the force of the setting spring 20 in the low pressure pilot valve 11 becomes greater than the water pressure on the secondary side, so the valve body 21 descends and opens, and the water pressure in the cylinder part 6 is transferred from the passage 44 to the low pressure pilot valves 1 to t11. It escapes to the secondary side through the connection port 11G, the communication port 15 and the pipe 1.4.13, and as a result, the pull body 7 opens.5 At this point, if the demand is large like during the day, the high pressure pilot A large amount of water is supplied by controlling the valve 10, and when demand is low such as at night, a small amount of water is supplied by controlling the low pressure pylon 1 to the valve 11.

That is, when the water pressure on the secondary side falls below l kg/c+J, the low pressure pilot valve 11 opens, and the valve body 7 opens to supply water, if the demand is high, the water pressure on the secondary side will further decrease. Therefore, during water supply, the opening operation of the valve body 7 is large and the rising level is high. 1 Therefore, as shown in FIG. Open the bottom end. As a result, the water pressure in the cylinder part 6 is adjusted between the hollow part 41, the passage 42, the pipe 48, the high pressure pilot 10, and the connection port 16 and the communication port 1.
5 and pipes 13.14 to the secondary side, thus providing a large water supply until the water pressure on the secondary side exceeds 3 kg/cm.

The water pressure on the secondary side is 1. When the low pressure pilot valve 11 opens, the water pressure on the secondary side will not fall to the rod end if the demand is low. Therefore, the opening movement of the valve body 7 and the valve body 4G is small, and the seal portion Q5 Hollow part 41
It does not reach the point of opening the bottom end of the .

Therefore, even though the high-pressure pylons 1-10 are maintained in an open state, the water supply is controlled by the opening and closing operations of the low-pressure pylons 1-11. In other words, a small amount of water is supplied at night to meet the demand. Therefore, by lowering the water pressure acting on the secondary side to prevent residual water, the life of the pipe member can be extended.

Further, although the valve body 46 is linked to the operation of the valve body 7, the two are connected with a play h, so that even if the valve body 7 is moved down by F- little by little, the valve 35 will not perform the switching operation too sensitively. The set pressure of the water supply is high pressure (3k/(ouch)) and low pressure (1
, k+; / c). As a result, the durability of the valve 35 is improved, and the pipe line that receives water supply is less susceptible to water hammer phenomenon.
It can also protect pipelines.

Incidentally, even if the Herofram 24 breaks due to the pressure acting on the pressure receiving chamber 18 of the Valve 1 to Valve 1.0.11, there is no problem because the other Herofuram 26 maintains watertightness.

Further, in this case, pressure is applied to the cylindrical body 32 of the detection body 31, and when the detection body 33 splits into two parts, a warning is given that the bellofram 24 has broken. Also.

Since the valve 35 is formed by coaxially fitting the outer cylinder 38, the switching body 39, and the valve body 46, the structure can be simplified and the size can be reduced.

In addition, since a part of the valve 4G protrudes from the outer cylinder 38, the amount of opening of the valve body 7 is increased. The opening amount of the valve body 7 can be clearly known by looking at the upper surface of the ring presser 53 or the like as a reference.

Effects of the Invention Since the present invention is configured as described above, by selecting the high pressure pylon 1 to valves and the low pressure pylon 1 to valves having different set pressures, it is possible to supply water in accordance with the demand. This allows the pressure on the secondary side to be lowered at night when demand is low, preventing shallow water and extending the life of pipe members. It is possible to make one small hit, and
By connecting the valve body of the differential pressure reducing valve with the valve stem of the valve with play, it is possible to prevent sensitive switching operation of the valve, increase the durability of the valve, and protect the pipeline. It has the following.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional royal view, FIG. 2 is an enlarged longitudinal sectional side view of high-pressure and low-pressure pylons 1 to '5↑, and FIGS. 3 and 4. is a vertical sectional side view showing an enlarged view of the operation of ↑. 1 Differential pressure reducing valve, 5 - Valve seat, 6 Cylinder part, 7
Bu 1 integrated, 10 High pressure pylon 1 to valve, 11 - Low pressure pylon 1 - valve, 1247 box, 15 - Communication port, 16 connection, 1. +7・bu? Seat, 18 Pressure receiving chamber, 20・Pressure setting spring, 21・Valve body, 35・-1t, 38 Outer cylinder, 3
9 Switching body, 11 Hollow part, 42. 44... Passage, 4
5 ・Seal part, 46 Bento 33 figure

Claims (1)

[Claims] A differential pressure reducing valve that opens and closes the valve seat between the primary side and the secondary side, and has a diameter on the opposite side larger than the diameter on the valve seat side (the valve body is slidably held in the cylinder part). A valve body is provided in each of the valve boxes in which a valve seat is formed between a communication port connected to the secondary side and a connection port, and a valve body that slides upon detecting the pressure on the secondary side and the secondary side. A high pressure pilot valve and a low pressure pilot valve are provided, each housing a pressure setting spring that urges the valve body in the opening direction by setting a force resisting the pressure of Fix the outer cylinder to the outer cylinder, fit a switching rod formed with a hollow part with one open end on the cylinder side into the outer cylinder, and always connect the cylinder part to the connection port of the low pressure pilot button t. H connects the annular passage and the hollow part to the high pressure pilot l to the connection 10 of the valve.
An annular passage connected to the outer cylinder and the switching rod is formed between the outer cylinder and the switching rod, and is inserted into the hollow part and connected to the open end of the hollow part by sliding movement in the axial direction. A valve stem is provided which opens the gap between the cylinder part and the valve stem, and the valve stem and the valve body of the differential pressure reducing valve are connected with each other with a play so as to allow slight movement in the axial direction. A pressure switching device for a pressure reducing valve, characterized in that a valve is formed by a rod, the outer cylinder, and the switching rod.