JPH08270806A - Automatic pressure regulating valve - Google Patents

Abstract

PURPOSE: To provide a valve device in which cavitation is not brought about and hunting is hard to occur by closing a large-diameter hole perforated in the partition wall of a valve main body by a large-diameter valve and integratedly moving the large-diameter valve to close it by a small-diameter valve when the small-diameter hole perforated in the large- diameter valve exceeds the range within which it can be independently moved in a fixed range with respect to the large-diameter valve. CONSTITUTION: When a hydraulic pressure in an outflow chamber 5 goes down to less than a predetermined pressure, a pilot valve 26 is opened to allow water in a communication chamber 20 to flow into the outflow chamber 5. Since the inflow of the water of the communication chamber 20 is adjusted so as to be smaller than the outflow of an outflow conduit tube 24, a piston 16 raises a cylinder 17 by a hydraulic pressure from a passage hole 22. Therefore, a small-diameter hole 8 is opened by a small-diameter valve 10 to gradually send the water of an inflow chamber 4 into an outflow chamber 5. Further, the small-diameter valve 10 is continuously raised with the rising of the piston 16, and when it abuts on an abutting plate 14, the large-diameter valve 6 integral with the abutting plate 14 is pulled up by the small-diameter valve 10 to gradually open the large-diameter hole of a partition wall 2. When a pressure inside the outflow chamber 5 goes up to the predetermined pressure, the pilot valve 26 is closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic pressure control valve used in, for example, waterworks.

[0002]

2. Description of the Related Art For example, in water supply of water supply, in order to minimize leakage of water in a water supply pipe, the water supply pressure is gradually reduced from the water source to the final water destination, and it is good. A pressure control valve is known that adjusts the amount of water supplied from a water source according to the use of water at a water destination in order to obtain a proper water supply state.

Various types of such pressure regulating valves are supplied, but generally, the pressure difference is constant by sandwiching the device to make the water source side high pressure and the water destination side low pressure. In the range of, the pressure control valve continues to maintain the closed state, and when the pressure on the water receiving side falls below a specified value due to the use of water in each household, for example, the valve is opened and the water It is designed so that water can be supplied from the water source according to demand.

[0004]

Although the pressure regulating valve which is opened by the pressure drop at the water destination of the conventional type can appropriately cope with a sudden and large pressure drop at the water destination, the pressure adjusting valve A small pressure drop is handled by opening the internal valve structure slightly, so that the large valve structure is opened slightly to respond to the small pressure drop, which is the worst operation in the valve structure. The situation is unavoidable.

It is undeniable that such an operation causes cavitation extremely easily, and it is the largest cause of hunting, and if such a state continues continuously and repeatedly, the pressure regulating valve main body will remain. Not to mention, it has a great adverse effect on various device parts connected thereto.

[0006] In order to reduce the occurrence of such troubles, the design of the pressure regulating valve is changed, and if more precise parts are incorporated to achieve the delicate operation of the valve structure, it is necessary to separate the valve body or its periphery. There is no choice but to install parts, which inevitably results in higher costs for the finished product.

[0007]

As described above, when a large-diameter valve is used with a small opening for a small flow rate, cavitation is likely to occur. The problem is that a small-diameter valve is used for a small flow rate. However, simply reducing the diameter of the valve cannot cope with the case where a large flow rate is required.

In order to eliminate such a dilemma, a small diameter valve having a small diameter and a large diameter valve having a large diameter are prepared, and a small diameter valve is used when the pressure drop on the water destination side is small, and a large diameter valve is used when the pressure drop on the destination side is large. By using a diameter valve together, it is considered possible to obtain a valve device that does not cause unnecessary cavitation and is less likely to cause hunting.

The relationship between these small-diameter valve and large-diameter valve is that at the start of operation, the small-diameter valve is first opened, and the small-diameter valve is fully utilized, and then the large-diameter valve is opened in a manner linked with the small-diameter valve. Is desirable.

Therefore, a large-diameter hole is bored in the partition wall of the valve body, which is closed by the large-diameter valve, and a small-diameter hole is bored in the large-diameter valve.
The small-diameter hole can be moved independently of the large-diameter valve within a certain range. For example, a small diameter valve operates for a small pressure drop, and a small diameter valve and a large diameter valve operate for a large pressure drop to obtain a corresponding device.

Further, considering the prevention of cavitation, when the circular hole is closed from the water source side by the valve plate as shown in FIG. 6, a peripheral edge which becomes the valve seat 9'is projected around the circular hole to form the valve plate. A sealing material 11 '(rubber disk or the like) fixed to 10' is pressed against the valve seat 9'to achieve the object. The sectional shape of the tip of the protruding peripheral edge of the valve seat 9'and the valve plate 10 Fixing plate 1 for fixing the sealing material to '
2'is a rectangular structure in cross section with their edges having corners, and the corners and the end face of the valve seat formed between them impede the smooth movement of the passing fluid, whereby two Cavitation is generated at a position close to the corner of the corner facing the water destination side.

Such cavitation naturally causes hunting, which causes vibration of the valve plate, generation of noise, and wear of nearby metal parts and sealing materials, which greatly affects the management and maintenance of the entire valve device. As shown in FIG. 6, such wear results in severe wear of the corners of the valve plate 10 ', the fixed plate 12', etc., as well as the portions A, B, C of the sealing material 11 '. .

Of course, it is impossible to completely remove the cavitation that may occur when the pressurized fluid is passed through the narrow space, but the fluid flow should be as smooth as possible. Also, by changing the position of cavitation by considering the shape of the void,
It is possible to suppress the influence of the metal portion of the valve device and the sealing material.

As a means for this, as shown in FIG. 5, it is effective to make the tip cross-sectional shape of the valve seat 9 and the edge of the fixing plate 12 of the sealing material 11 a semicircle or a curved surface, whereby the water supply of the valve seat 9 is performed. It is possible to smooth the water flow on the source side, reduce the amount of cavitation generated on the water destination side, and further move the cavitation generation position to a position further away from the valve seat 9 and the sealing material 11.

In addition, to open the small diameter valve and the large diameter valve,
First, the small-diameter valve is opened, and then these valves are connected to each other so as to open the large-diameter valve in a manner suspended by the small-diameter valve, and the small-diameter valve is connected to the piston rod of the piston that is moved by hydraulic pressure and is driven. As a result, the movement of the piston is transmitted to the small diameter valve to open it, and when the small diameter valve moves over a certain range, the large diameter valve is opened and the required large pressure is supplied.

A piston for driving the small diameter valve and the large diameter valve is arranged in a cylinder installed above the small diameter valve in the main body of the valve device, and the cylinder divides the distribution chamber and the storage chamber by the piston.

When the storage chamber is connected to the inflow chamber (the water source side) of the valve body and the cylinder is installed so that the piston moves in the vertical direction, the water pressure of the inflow chamber is always the piston pressure in the storage chamber. It is added to the bottom surface.

The flow chamber is provided on the upper surface of the piston in the cylinder and is connected to the inflow chamber of the valve body and the outflow chamber of the valve body (destination side), and between the inflow chamber of the main body and the flow chamber of the cylinder. A flow rate controller and strainer are installed, and a pilot valve is installed between the flow chamber of the cylinder and the flow chamber of the main body.When the pilot valve is opened, part of the water in the flow chamber of the cylinder is It flows into the outflow chamber,
Along with that, the water in the inflow chamber of the main body passes through the flow rate control device, the strainer, etc., and flows into the circulation chamber of the cylinder to try to supplement the pressure lost in the circulation chamber of the cylinder.

The small-diameter valve closes the small-diameter hole of the large-diameter valve which closes the large-diameter hole of the valve body partition, and the piston for opening the small-diameter valve is located at the lowermost end of the cylinder. With the valve body closed with the valve closed,
The upper and lower surfaces of the piston and the surfaces of the small-diameter valve and the large-diameter valve facing the inflow chamber receive the same water pressure from the inflow chamber of the main body, so that the piston can maintain its position and the small-diameter valve and the large-diameter valve It is pressed against the valve seat corresponding to them.

When water is used at the water supply destination connected to the outflow chamber of the valve body and the pressure in the outflow chamber becomes lower than the open set pressure of the pilot valve, the small diameter valve and the large diameter valve remain closed,
Water in the circulation chamber of the cylinder flows into the outflow chamber of the valve body via the pilot valve, and the water pressure in the circulation chamber is reduced. In this case, water is supplied from the inflow chamber of the valve body to the circulation chamber of the cylinder, but by appropriately setting the flow rate adjusting device interposed in this flow path in advance, the water can be supplied to the circulation chamber. Control to be slow.

In such a state, the pressure in the flow chamber of the cylinder greatly decreases, the water in the inflow chamber flows into the storage chamber and pushes up the piston, and the movement of the piston moves with the small diameter valve connected by the piston rod. And the water in the inflow chamber flows into the outflow chamber through the small diameter hole that has been closed by the small diameter valve. When the pressure on the water destination side rises above the set pressure of the pilot valve due to this inflow, the pilot valve closes, the pressure in the flow chamber of the cylinder gradually rises, and the pressure on the upper and lower surfaces of the piston becomes equal. The small-diameter valve and the piston are lowered by the pressure on the water supply side applied to the small-diameter valve, and the small-diameter valve closes the small-diameter hole and stops.

When it is not enough to open the small diameter valve, the small diameter valve rises to a certain extent as the piston moves up to open the small diameter hole, and then the small diameter valve further rises and the large diameter valve is pulled up to a large size. The diameter hole is opened, and the water in the inflow chamber flows into the outflow chamber from the large diameter hole. By this, when the water pressure reaches the set pressure of the pilot valve, the pilot valve is closed, the pressure in the flow chamber rises, and the same operation as when the small diameter valve described above is closed,
The large hole and the small hole are closed.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete embodiment of the present invention will be described with reference to FIGS. 1 to 4. In the drawings, 1 is a valve device main body, 2 is a partition wall having a large diameter hole 3 formed therein, and the valve device main body 1 is provided with an inflow chamber. It is divided into 4 (water sending side) and outflow chamber 5 (water sending side). Reference numeral 6 denotes a large-diameter valve having a seal ring 7 and a small-diameter hole 8 formed on the lower peripheral edge thereof, and a projecting edge installed upward on the peripheral edge of the small-diameter hole 8 has a valve seat 9. Formed and large-diameter valve 6
Is in the inflow chamber 4 and closes the large diameter hole 3 of the partition wall 2.

The small-diameter valve 10 for closing the small-diameter hole 8 is the large-diameter valve 6
A seal member 1 installed on the upper surface of the valve for abutting against the valve seat 9 of the small diameter hole 8 of the large diameter valve 6 to close the small diameter hole 8.
1 is fixed via a solid plate 12, and a piston rod 13 is projectingly provided on the upper surface thereof. The lower surface of the small-diameter valve 10, the lower surface of the fixed plate 12, and the corners existing on the upper edge of the valve seat 9 are all formed by curved surfaces so that cavitation generated by the water flow being disturbed by the corners is attenuated. It is devised.

Reference numeral 14 is a connecting plate through which the piston rod 13 penetrates and is fixed to the large-diameter valve 6 by connecting legs 15 and 15. The small-diameter valve 10 is independent between the large-diameter valve 6 and the connecting plate 14 by a certain range. When the piston rod 13 rises when the two large and small valves are closed as shown in FIG. 4, the small diameter valve 10 first starts to rise and the small diameter hole 8 is formed as shown in FIG. When the small-diameter valve 10 is opened and abuts on the connecting plate 14 and raises it as shown in FIG. 2, the large-diameter valve 6 rises accordingly and the large-diameter hole 3 is opened.

Reference numeral 16 denotes a piston which slides in the cylinder 17 arranged above the valve device main body 1 in the vertical direction in the figure,
The piston rod 3 of the small diameter valve 10 is fixed to the lower surface thereof, and the operation rod 18 is extended to the upper surface thereof. The cylinder 16 is divided into upper and lower chambers by the piston 16, and the upper opening of the cylinder 17 is closed by the lid body 19 to form the flow chamber 20 by the piston 16 and the lid body 19. Piston 1
A storage chamber 21 is formed by 6.

A through hole 2 is formed in the lower bottom surface 17 'of the cylinder 17.
2, the inflow chamber 4 and the storage chamber 22 are communicated with each other, and the flow chamber 20 above the cylinder 17 is connected to the inflow conduit 2
3 is connected to the inflow chamber 4 of the valve body 1 and the outflow conduit 2
It is connected to the outflow chamber 5 by 4.

The inflow conduit 23 is provided with a control unit 25 in the middle thereof. The control unit 25 is composed of an orifice, a check valve, a strainer, etc., and flows from the inflow chamber 4 of the valve body 1 into the flow chamber 20 of the cylinder 17. Adjust the degree of pressure water inflow.

The outflow conduit 24 is provided with a pilot valve 26 whose pressure is set in advance in the middle portion thereof, and when the pressure acting on the pilot valve 26 falls below a set value, the pilot valve 26 opens and the cylinder 17 of the cylinder 17 is opened. Water in the circulation chamber 20 flows out to the outflow chamber 5 of the valve body 1 through the outflow conduit 24.

Reference numeral 27 denotes a screw-in handle which is installed so as to face the operation rod 18 which is airtightly projected from the lid 19.
By rotating this, the screw shaft 27 'is lowered as shown in FIG. 3, and the operating rod 18 is pushed down to lower the piston 16, the piston rod 13, and the small diameter valve 1.
It is possible to lower 0 and close the large diameter hole 3 and the small diameter hole 8.

Reference numeral 28 denotes an exhaust valve installed on the lid body 19, which is used for exhausting the air in the flow chamber 20 of the cylinder 17 when the setting for starting the apparatus is performed.

The outline of the procedure for inserting the valve body 1 into the water supply circuit will be described below. An upstream pipe 29 connected to the inflow chamber 4 of the valve body 1 and a downstream pipe 30 connected to the outflow chamber of the valve body 1. Each has a sluice valve (not shown) installed, and these sluice valves are closed to cut off the water supply before the work is performed.

When the valve body 1 is installed, the screwing handle 27 is rotated to lower the screw shaft 27 'to completely close the large diameter hole 3 and the small diameter hole 8 and close the pilot valve 26 as shown in FIG. Keep it. When the valve body 1 thus configured is liquid-tightly fixed between the upstream pipe 29 and the downstream pipe 30 and the upstream sluice valve is opened, the water on the water source side will flow from the inflow chamber 4 to the lower side of the cylinder 17. It flows into the storage chamber 21 of the cylinder 17 through the through hole 22 formed in the bottom surface 17 ′ and into the flow chamber 20 of the cylinder 17 through the inflow conduit 23.

At this time, the exhaust valve 28 is opened to open the flow chamber 20.
The residual air in the inside is exhausted, the sluice valve on the downstream side is opened when the inflow of the water into the inflow chamber 4 and the distribution chamber 20 is stabilized, and the water in the downstream pipe 30 is introduced into the outflow chamber 5 of the valve body 1. Fulfill. In this state, the upstream pipe 29 is separately prepared by the water pressure measuring means.
Also, the water pressure in each of the downstream pipe 30 is measured, and the pilot valve 26 is adjusted so that the pilot valve 26 opens when the water pressure in the downstream pipe 30 falls below a predetermined value.

When the above procedure is completed, the screw-in handle 27 is rotated in the reverse direction to raise the screw shaft 27 'and the operating rod 1
8 is released, and the large-diameter valve 6 and the small-diameter valve 10 are left at the positions shown in FIG. 4 to complete the installation work.

The operation will be described. When the water pressure in the downstream pipe 30 and the outflow chamber 5 of the valve body 1 falls below a predetermined pressure, the closed pilot valve 26 is opened and the water in the flow chamber 20 flows out. It flows into the outflow chamber 5 via 24. The water is supplied to the distribution chamber 20 by the inflow conduit 23, but since the inflow amount is adjusted to be smaller than the outflow amount by the outflow conduit 24 by the interposing control unit 25, the piston 16 is moved to the distribution chamber 20. The pressure received by the water in the storage chamber 21 is lower than the pressure received by the water in the storage chamber 21, and the piston 16 is raised in the cylinder 17 by the pressure of the water continuously supplied from the through hole 22 to the storage chamber 21. Become.

When the piston 16 moves up, the small diameter valve 10 connected to the piston 16 by the piston rod 13
Also rises to open the closed small diameter hole 8 and gradually send the water in the inflow chamber 4 into the outflow chamber 5. In this case, the large diameter valve 6 provided with the small diameter hole 8 does not move and continues to close the large diameter hole 3 of the partition wall 2.

When the pressure in the outflow chamber 5 does not rise to a desired value even if water is fed from the small diameter hole 8 as described above (the water pressure in the outflow chamber 5 is extremely low, it is insufficient to feed a small amount of water). In this case), the pilot valve 26 continues to be opened, and the water in the flow chamber 20 continues to flow through the outflow conduit 24, so that the pressure in the outflow chamber 20 further decreases, and the decrease in pressure causes a further rise in the piston 16. produce.

By further raising the piston 16, the small diameter valve 1
When 0 continues to rise and comes into contact with the connecting plate 14, the small-diameter valve 10 pulls up the large-diameter valve 6 integrated with the connecting plate 15, so that the large-diameter valve 6 rises and closes the large size of the partition wall 2. Bore 3
Gradually open. Thereby, the inflow chamber 4 to the outflow chamber 5
The delivery of water to is greatly increased, resulting in a rapid increase in the pressure in the outflow chamber 5.

The pressure in the outflow chamber 5 increases and the pilot valve 2
When it becomes equal to the set value of 6, the pilot valve 26 is first closed, the outflow of water from the distribution chamber 20 is stopped, the water in the inflow chamber 4 is supplied from the inflow conduit 23 to the distribution chamber 20, and the distribution chamber 20 is also supplied. Since the internal pressure increases and the pressure applied to both the upper and lower surfaces of the piston 16 becomes equal, the piston 1
6 descends due to the pressure of the water applied to the large-diameter valve 6 and the small-diameter valve 16, first the large-diameter valve 6 closes the large-diameter hole 3, and then the small-diameter valve 10 closes the small-diameter hole 8 to inflow. The movement of water from the chamber 4 to the outflow chamber 5 is stopped.

In the valve device of the present invention thus closed, only the small diameter valve 10 operates to open the small diameter hole 8 when the required water amount is small, and the small diameter valve 10 when the large water amount is required. In addition to 10, the large-diameter valve 6 operates to open the large-diameter hole 3 so as to respond to each necessary situation.

According to the present invention, inflow conduit 23 is provided for the outflow of water in distribution chamber 20 due to the opening of pilot valve 26.
Since the inflow of water into the flow chamber 20 by the control unit 25 can be controlled by the control unit 25, the movement of the piston 16 for opening the small diameter valve 10 can be freely adjusted, and the small diameter valve 10 can be opened when the pilot valve 26 is opened. Can be adjusted so as to move extremely slowly and smoothly, so that the occurrence of cavitation can be minimized.

Further, since the upper edge of the valve seat 9, the lower edge of the small diameter valve 10 and the edge of the fixing plate 12 are all sharpened so as to form a curved surface, the water flow has a sharp corner. Even if a backward vacuum occurs, it will occur at a place away from such an edge without causing cavitation immediately by the cavitation, it does not cause hunting, etc. The wear can be removed almost completely.

[0044]

As described above, when the required flow rate is small, the small-diameter valve is opened to accommodate the small flow rate. Compared to the model, turbulence around the valve is less likely to occur and cavitation can be suppressed as much as possible.
Hunting, which causes failure of the valve element, can be almost completely prevented, and by adjusting the pressure receiving area of the small diameter valve and the large diameter valve and the pressure receiving area of the piston appropriately, it is possible to reduce the pressure on the water source side. It is possible to achieve the ideal balance of pressure on the water destination side, and further adjust the pilot valve and flow rate control device to appropriately adjust the movement of water in the circulation chamber of the cylinder to open the gradual opening of the small diameter valve. As a result, it is possible to significantly suppress cavitation and remove hunting in addition to changing the cross-sectional shape of the valve seat installed in the small diameter hole. effective.

[Brief description of drawings]

FIG. 1 is a conceptual view showing a state in which only a small diameter valve is opened in a cross section of the present invention.

FIG. 2 is a conceptual diagram showing a state in which a small diameter valve and a large diameter valve are opened in a cross section of the present invention.

FIG. 3 is a conceptual diagram showing a state in which a small diameter valve and a large diameter valve are fixed to a closed position by a screw shaft in a cross section of the present invention.

FIG. 4 is a conceptual diagram showing a state in which a small diameter hole and a large diameter valve are closed without fixing the small diameter valve and the large diameter valve in the cross section of the present invention.

FIG. 5 is a partial sectional view of a valve seat and a small diameter valve according to the present invention.

FIG. 6 is a partial cross-sectional view of a conventional valve seat and a small diameter valve. 1 Valve body 2 Partition wall 3 Large diameter hole 4 Inflow chamber 5 Outflow chamber 6 Large diameter valve 7 Seal ring 8 Small diameter hole 9 Valve seat 10 Small diameter valve 11 Seal material 12 Fixing plate 13 Piston rod 14 Connecting plate 15 Connecting leg 16 Piston 17 Cylinder 17 'Lower bottom surface 18 Operation rod 19 Lid body 20 Flow chamber 21 Storage chamber 22 Through hole 23 Inflow conduit 24 Outflow conduit 25 Control part 26 Pilot valve 27 Screw-in handle 27' Screw shaft 28 Exhaust valve 29 Upstream pipe 30 Downstream pipe

Claims (3)

[Claims] 1. A valve body divided into an inflow chamber and an outflow chamber by a partition having a large diameter hole, a cylinder divided into a flow chamber and a storage chamber by a piston, and a large diameter valve closing the large diameter hole. And a small-diameter valve that closes a small-diameter hole formed in the large-diameter valve.The flow-in chamber of the valve body and the flow chamber of the cylinder, and the flow-out chamber of the valve body and the flow chamber of the cylinder are provided with appropriate flow control devices or By connecting via a pilot valve, etc., the inflow chamber of the valve body and the storage chamber of the cylinder are communicated, and the piston in the cylinder and the small diameter valve in the inflow chamber are connected by a piston rod, which is independent of the small diameter valve within a certain range. The small-diameter valve and the large-diameter valve are movably connected while allowing movement, and the small-diameter valve closes the small-diameter hole of the large-diameter valve when the piston is in a position that minimizes the cylinder storage chamber space. Adjusted to close large holes in bulkhead , The decrease of the pressure of the outflow chamber of the main body decreases the pressure of the flow chamber of the cylinder, the fluid of the inflow chamber of the main body flows into the storage chamber of the cylinder to move the piston, and first of all, it was connected to the piston rod. When the small-diameter valve is moved to open the small-diameter hole of the large-diameter valve, and when the pressure in the outflow chamber further decreases, the piston moves further and the small-diameter valve moves to the limit of the movable range and moves the large-diameter valve to move the partition wall. An automatic pressure control valve characterized by opening a large-diameter hole drilled in the. 2. A small diameter valve is closed by a small diameter valve by bringing the edge of the small diameter hole projecting toward the small diameter valve into contact with the packing of the small diameter valve, and making the cross-sectional shape of the tip of the edge semicircular. The automatic pressure regulating valve according to claim 1, wherein 3. A small-diameter valve is closed by a small-diameter valve by bringing the edge of the small-diameter hole projecting toward the small-diameter valve into contact with the packing of the small-diameter valve, so that the cross section of the edge has a semicircular shape. The automatic pressure regulating valve according to claim 1, wherein the corner portion of the packing holding metal fitting of the small diameter valve is formed by a curved surface.