JP3851378B2 - Automatic adjustment valve device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an automatic adjustment valve device provided with an automatic throttle adjustment flow path installed in a fluid transportation pipeline, and more specifically, Japanese Patent Application No. 8-26828 “Automatic constant pressure valve device” (hereinafter “original invention”). ")". That is, as an automatic constant pressure valve device that is convenient for water supply / distribution, etc., it can be easily increased in size and pressure without the need for management and without having to worry about water tightness at the time of water stoppage. For example, all fixed throttle control channels such as needle valves and cocks are excluded from the device, and when each valve is clogged, each valve body automatically opens and has a function of performing a sweeping flow. Let's obtain an epoch-making automatic regulating valve device that not only functions as an automatic constant pressure valve, but also has a function of automatically restricting the flow rate so that the flow rate supplied to the downstream side does not exceed a predetermined amount It is what.
In the present specification, the term “water” generically represents fluid.
[0002]
[Prior art]
As a conventional general pressure regulating valve device, a pilot valve device that detects the fluid pressure in the outlet pipeline system and operates it while restricting the flow rate with a fixed throttle adjusting flow path such as a needle valve. Therefore, a structure for operating a piston for driving a main valve has been widely used.
However, in these conventional general pressure regulating valve devices, there are many concerns about the troublesomeness and durability in maintenance management, and for example, there are the following difficult problems.
(1) Many pistons for driving the main valve require a perfect water tightness that does not allow water leakage at the time of closing. Especially, as the size and pressure increase, the durability and processing accuracy of the seal part become difficult. It is also troublesome for maintenance management.
(2) In order to prevent pressure pulsation (hunting) due to a sudden flow change, in order to drive the main valve slowly, a communication passage that introduces a pressure fluid upstream of the main valve to the piston for driving the main valve A fixed throttle channel such as a needle valve is required on the way, and clogging such as sand particles and dust is likely to occur in the fixed fine channel.
(3) In addition, the adjustment to set the required downstream pressure of the main valve is an adjustment that takes into account the balance between the fixed throttle flow path such as the needle valve and the pilot valve device. It takes a hand.
[0003]
By solving these problems, the pilot valve device that does not have a fixed throttle flow path such as a needle valve prevents clogging accidents, and there is no water leakage when the main valve device is closed. Japanese Patent Application No. 8-26828 “Automatic constant pressure valve device” of the original invention proposed a pressure regulating valve device having a clear mechanism capable of maintaining the pressure at a predetermined value.
The configuration is as described in the patent application specification, and the gist is (illustrated in FIG. 3).
The main valve device comprises a main valve body 5 and a main valve drive member 6 which are integrally incorporated in the main valve box 1, and the main valve body 5 is located on the upstream side of the main valve seat 3 and between them. A valve opening b is formed, and the main valve drive member 6 is slidably fitted to the cylindrical inner wall portion 8 of the main valve box 1 so as to be slidable between the main valve box lid 2 and the main valve drive pressure chamber d. Configured to form a structure,
The pilot valve device is composed of a pilot A valve portion and a B valve portion on the same axis that are operated by a balance of the acting force between the downstream pressure of the main valve device and one predetermined additional external force means, and the main valve downstream pressure is predetermined. When the value is within the value, the pilot A valve portion that is kept almost closed and opened when the pressure on the downstream side of the main valve becomes lower than a predetermined value, and the pilot B valve that opens when the pressure on the downstream side of the main valve becomes higher than a predetermined value Is connected in series between the inlet channel a and the outlet channel c via the main valve driving pressure chamber d, so that the pilot valve device for driving the main valve does not have a fixed throttle channel It is configured in the structure.
In addition, a variable orifice 12 may be provided in the outlet flow path of the main valve device.
[0004]
[Problems to be solved by the invention]
This original invention, when viewed as a constant pressure valve itself, achieves its purpose well and is utilized as a simple and high-performance constant pressure valve, however, there still remains a problem in light of actual use conditions. . This is because, in actual use, there is often a request to function as a constant pressure valve during normal use, while functioning as a constant flow valve that restricts the flow rate when the downstream use flow rate becomes excessive. In such a case, the automatic constant pressure valve device according to the present invention cannot be used alone. This is because in this apparatus, when the downstream use flow rate is excessive and a pressure drop occurs on the downstream side, the main valve is increased in the direction of increasing the flow rate by the original function of the constant pressure valve to compensate for the pressure drop. This is because the device operates.
In the original invention, a constant flow rate can be achieved by providing a variable orifice 12 in the outlet flow path of the main valve device, but this is the case when there is no on-off valve or flow rate adjusting valve on the use terminal side of the pipeline. It is a theory that holds, and in reality, it is normal to perform flow channel opening and closing and flow rate adjustment at the point of use of the water at the pipe end. In that case, it is not possible to maintain a constant flow rate simply by providing the orifice 12. Of course.
It seems that it is difficult to combine the function as the constant pressure valve and the function as the constant flow valve with a simple configuration. Conventionally, the constant pressure valve and the constant flow valve are arranged in two or downstream. Usually, an expensive sensor or a switching device is provided for switching the functions of the constant pressure valve and the constant flow valve in accordance with the flow rate on the side.
[0005]
This invention solves the remaining problems in the original invention as described above, there is no leakage at the time of shutting off the main valve device, and there is no clogging accident because there is no fixed throttle channel such as a needle valve, In addition, each valve unit has a self-sweep function and maintenance is not involved. All the advantages of the original invention are fully utilized, and both the constant pressure valve and constant flow valve functions are compatible with each other. An object is to obtain a regulating valve device.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an automatic adjustment valve device according to the present invention provides:
In a self-regulating valve device in which a main valve device is driven in conjunction with a pilot valve device operated by a change in pressure of fluid flowing through it,
The main valve device has a main valve body integrally incorporated in the main valve box and a main valve drive member having a larger pressure receiving area than the main valve body, and the main valve body is located upstream of the main valve seat. The throttle valve is formed between the main valve seat and the main valve drive member is slidably fitted to the cylindrical inner wall portion of the main valve box, and between the inner wall portion and the main valve seat. Forming the main valve drive pressure chamber,
The pilot valve device has a pilot A valve portion and a pilot B valve portion on the same axis, which are operated by a balance of the opposing acting force between the downstream pressure of the main valve device and the predetermined additional external force means, and on the downstream side of the main valve When the pressure is at a predetermined value, both remain substantially closed, and the pilot A valve portion that opens when the pressure on the downstream side of the main valve becomes lower than the predetermined value, and opens when the pressure on the downstream side of the main valve becomes higher than the predetermined value And the pilot B valve portion that communicates in series between the inlet passage and the outlet passage of the main valve device via the main valve driving pressure chamber in the middle,
A differential pressure cylinder device that operates by a balance between the opposing differential force of the front and rear differential pressures of the orifice provided in the flow path of the main valve device and the predetermined additional external force means is attached to the pilot valve device, and the orifice If the differential pressure before and after becomes higher than a predetermined value, the piston shaft of the differential pressure cylinder device pushes the valve shaft of the pilot valve device in a direction opposite to the force of the predetermined additional external force means of the pilot valve device. It is characterized by that.
The orifice may be a variable orifice.
[0007]
[Action]
In the self-regulating valve device according to the present invention, when the pressure on the downstream side of the main valve changes due to a large amount of downstream use flow rate at the time of water flow, both are substantially closed when the pressure on the downstream side of the main valve is at a predetermined value. The pilot A valve portion that is opened when the pressure on the downstream side of the main valve is lower than a predetermined value, and the pilot B valve portion that is opened when the pressure on the downstream side of the main valve is higher than a predetermined value performs a linked operation. A predetermined main valve downstream pressure is maintained while adjusting the opening of the main valve body by appropriately increasing or decreasing the internal pressure of the main valve driving pressure chamber.
If the downstream operating flow rate does not exceed the specified amount under the condition of operating as a constant pressure valve, the piston shaft of the differential pressure cylinder device is separated from the valve shaft of the pilot valve device. It does not interfere with the operation of the device as a constant pressure valve.
On the other hand, if the flow rate on the downstream side is excessive and it is likely to exceed the predetermined amount, the piston shaft of the differential pressure cylinder device is controlled by the valve of the pilot valve device due to the expansion of the differential pressure across the attached orifice. Abuts against the shaft and pushes in a direction opposite to the force of the predetermined additional external force means of the pilot valve device, causing the main valve body to perform the closing operation by interfering with the operation as a constant pressure valve, and passing the flow rate by a predetermined amount To maintain.
[0008]
When the use on the downstream side ends and the terminal pipe line is closed, the pilot A valve portion is closed and the B valve portion is opened due to the accompanying increase in the pressure on the downstream side of the main valve, thereby opening the main valve body. Is closed to maintain the main valve downstream pressure at a predetermined value. At this time, since the differential pressure across the attached orifice decreases due to the decrease in the flow rate due to the closing operation of the terminal pipe line, the piston shaft of the differential pressure cylinder device returns to the state separated from the valve shaft of the pilot valve device. It does not interfere with the operation as a constant pressure valve.
[0009]
According to the configuration of the present invention, even if the seal member of the main valve driving member is left with rough watertightness, abnormal pressure increase of the main valve downstream pressure does not occur. In addition, when any of the main valve device, pilot A valve part, and B valve part is clogged with sand particles, dust, etc., the valve is automatically activated by the change in the pressure on the downstream side of the main valve caused by the clogging. It also has a function of opening the valve and eliminating clogging by self-cleaning flow.
[0010]
【Example】
Details of the present invention will be described with reference to FIG. 1 showing an embodiment.
In the following, for convenience, the pilot A valve part is “A valve part”, the valve body is “A valve body”, the pilot B valve part is “B valve part”, the valve body is “B valve body”, The main valve upstream pressure is referred to as “primary pressure”, and the main valve downstream pressure is referred to as “secondary pressure”.
First, in the figure of the main valve device in FIG. 1, 1 indicates a main valve box having an inlet channel a and an outlet channel c2, and 2 indicates a main valve box lid. 3 is a main valve seat. In the main valve box 1, a main valve body 5 provided on the upstream side with respect to the main valve seat 3 and a cylindrical inner wall portion 8 of the main valve box 1 are slidably fitted via a seal member 6s. The main valve drive member 6 mounted and the main valve shaft 4 that integrally combines the two members 5; 6 are provided. The main valve drive member 6, the cylindrical inner wall 8 and the main valve box lid 2 are wrapped to form a bag chamber-like main valve drive pressure chamber d. It is opened and closed. The relationship of the pressure receiving area between the main valve body 5 and the main valve driving member 6 is set so that the main valve driving member 6 is larger. Even when the main valve is closed, the seal member 5s of the main valve body 5 and the seal member 24s of the A valve body 24 of the pilot valve device have a strict watertight function. The member 6s is sufficient with a rough water-tightness to the extent of preventing current flow.
[0011]
In the figure of the pilot valve device, reference numeral 21 denotes a valve box forming the A valve part, the B valve part and the secondary pressure chamber i, and 22 denotes a valve box cover. Reference numeral 23 denotes a pressure receiving plate, 28 denotes a seal member, and 26 denotes a valve shaft that integrally combines the A valve body 24 and the B valve body 25 with the pressure receiving plate 23. A spring 27 as a predetermined additional external force means is accommodated in the spring chamber j of the valve box cover 22. In the A valve portion, an A valve chamber e, an A valve body 24, and an A valve seat chamber f are disposed. And about the A valve body 24, in order to show the exact | strict watertightness at the time of closure, 24 s sealing member is shown in figure. In the B valve portion, a B valve chamber g (same as the A valve chamber e), a B valve body 25, and a B valve seat chamber h are disposed. And it is shown that the B valve body 25 does not need strict water tightness at the time of closing, and may be somewhat leaky. (Of course, the B valve body 25 may be added with strict water tightness.) The A valve portion and the B valve portion are not only in a state where one is opened and the other is closed, but both Both valve parts are disposed at a position interval that can also produce a state of being substantially closed.
[0012]
In the drawing of the differential pressure cylinder device, 31 indicates a cylinder body, and 32 indicates a cylinder lid. Reference numeral 33 denotes a piston, and 34 denotes a piston shaft fixed to the piston 33. The pressure receiving area of the piston 33 is set larger than the pressure receiving area of the pressure receiving plate 23 of the pilot valve device. The piston shaft 34 is biased in a direction away from the pilot valve shaft 26 by a spring 35 as a predetermined additional external force means. An orifice front pressure chamber u is formed on the side far from the pilot valve shaft 26 with the piston 33 in between, and an orifice rear pressure chamber w is formed on the side near the pilot valve shaft 26.
Note that the piston 33 does not require strict watertightness between the inner wall of the cylinder 31 and may be somewhat leaky. (Of course, it is possible to add strict water tightness to the piston 33.)
[0013]
The A valve seat chamber f of the pilot valve device is communicated with the primary pressure inlet passage a through the communication passage P, and the A valve chamber e (same as the B valve chamber g) is communicated with the main valve drive pressure chamber d through the communication passage Pe. The B valve seat chamber h is communicated with the secondary pressure outlet channel c2 through the communication passage Q2. The secondary pressure chamber i communicates with the secondary pressure outlet channel c2 via the communication path Q2.
The orifice front pressure chamber u of the differential pressure cylinder device is communicated with the flow path c1 on the front surface (inlet side) of the orifice 12 through the communication passage Q1, and the orifice rear pressure chamber w is communicated with the rear surface (outlet side) of the orifice 12 through the communication passage Q2. ).
[0014]
The mode of operation of the present invention will be described with reference to FIG. 1 showing one embodiment.
When the fluid shown in FIG. 1 is inserted into the fluid transport pipe and the water is passed through, the outlet channel c2 does not reach the predetermined pressure yet, and the force of the spring 27 of the pilot valve device is the secondary pressure in the secondary pressure chamber i. Therefore, the A valve body 24 is opened, and at the same time, the B valve body 25 is closed, and the primary pressure flowing water from the inlet channel a is communicated with the communication path P → A valve seat chamber f → A valve chamber e → flows into the main valve drive pressure chamber d of the main valve device via the communication passage Pe. The primary pressure flowing water gradually moves the main valve driving member 6 having a pressure receiving area larger than that of the main valve body 5 from the fully closed state of the main valve body 5 to the fully opened direction with a pressure difference caused by the area difference. Open. Then, the fluid starts to flow through the flow paths a → b → c1 → c2. Therefore, the structure of the main valve device according to the present invention exhibits an excellent operation characteristic that an abnormal pressure increase of the secondary pressure does not occur even in a sudden direct start-up such as a water pump.
[0015]
Next, after the secondary pressure reaches a predetermined value, the secondary pressure that changes due to the amount of the downstream use flow rate is received, and the A valve body 24 of the pilot valve device, the A valve body 24 of the B valve portion, B The valve body 25 responds, and the internal pressure of the main valve drive pressure chamber d is appropriately increased or decreased to maintain a predetermined secondary pressure while adjusting the opening of the main valve body 5. When the secondary pressure is balanced and stable, both the A valve body 24 and the B valve body 25 are stabilized in a substantially closed state.
[0016]
If the downstream operating flow rate does not exceed a predetermined amount under the condition of operating as this constant pressure valve, the force of the spring 35 of the differential pressure cylinder device is superior to the differential pressure before and after the orifice 12. The piston shaft 34 of the differential pressure cylinder device is separated from the valve shaft 26 of the pilot valve device and does not interfere with the operation of the pilot valve device as a constant pressure valve.
On the other hand, if the downstream use flow rate becomes excessive and exceeds a predetermined amount, the differential pressure before and after the orifice 12 increases and rises accordingly, and the difference applied to the piston 33 of the differential pressure cylinder device. The pressure overcomes the force of the spring 35, and the piston shaft 34 abuts the valve shaft 26 of the pilot valve device and pushes it in a direction opposite to the force of the spring 27 of the pilot valve device (that is, prior to the operation as a constant pressure valve). have a finger in the pie). As a result, the A valve body 24 is closed, the B valve body 25 is opened, the internal pressure of the main valve drive pressure chamber d of the main valve device is reduced toward the secondary pressure, and the main valve body 5 is placed on the front and rear surfaces thereof. The closing operation is performed by the difference in the acting thrust, the main valve opening b is throttled, and the passing flow rate is maintained at a predetermined amount.
[0017]
The secondary pressure can be set to an intended value by simply adjusting the force of the spring 27 of the pilot valve device by the spring force adjusting portion 29, and the force of the spring 35 of the differential pressure cylinder device can be set to the spring force adjusting portion. The flow rate can be set to a desired value simply by adjusting with 36 or simply by restricting the orifice 12 with the handle 13 or the like.
[0018]
When the use on the downstream side is over and the terminal pipe is closed, the secondary pressure rises accordingly, and the secondary pressure applied to the pressure-receiving plate 23 of the pilot valve device overcomes the force of the spring 27, Push it back. The A valve body 24 is closed, the B valve body 25 is opened, the internal pressure of the main valve drive pressure chamber d of the main valve device is reduced toward the secondary pressure, and the main valve body 5 is The main valve opening b is closed and the flow is stopped, and the secondary pressure on the downstream side maintains a predetermined value.
At this time, since the differential pressure before and after the orifice 12 decreases due to the decrease in the flow rate due to the closing operation of the terminal pipe line, the force of the spring 35 of the differential pressure cylinder device overcomes the differential pressure before and after the orifice 12, The piston shaft 34 is returned to a state separated from the valve shaft 26 of the pilot valve device. (In other words, it does not interfere with the operation as a constant pressure valve)
[0019]
At the time when the main valve device completes the cutoff, according to the configuration of the present invention, the parts that should strictly perform the watertight function are the seal member 5s of the main valve body 5 and the seal member 24s of the A valve body 24, Both are members that can easily achieve water tightness by conventional techniques. On the other hand, even if the seal member 6s of the main valve drive member 6 which is more difficult to manufacture with precision is left with rough watertightness, abnormal pressure increase on the downstream side of the main valve does not occur. In addition, when any of the main valve device, the A valve portion, and the B valve portion is clogged with sand particles, dust, etc., the valve is automatically opened due to a change in secondary pressure or the like caused by the clogging. It has an excellent function of operating and eliminating clogging by self-cleaning flow. Therefore, a fine strainer or the like is not necessary, and maintenance management is easy.
[0020]
Next, the embodiment of FIG. 2 will be described. This shows an embodiment in which the main valve driving member 6 is provided on the upstream side of the main valve seat 3 as opposed to that of FIG. The operation direction of the main valve driving member 6 is reversed, the positions of the A valve portion and the B valve portion are reversed from those in FIG. The intended effect is the same as that of FIG.
[0021]
Next, other application examples will be described.
With regard to the structure of the pilot valve device, in any of the embodiments shown in FIGS. 1 and 2, the A valve body 24 and the B valve body 25 are provided on the single valve shaft 26 so that one predetermined additional external force means is provided. On the other hand, the two valve bodies 24; 25 are structured so as to be integrally interlocked with each other and do not interfere with each other's operation. In FIG. 1, an example in which the A valve body 24 and the B valve body 25 coexist in the valve chamber e is illustrated.
The design (positional relationship) and combination of the chambers e; f; g; h; i; j; u; w of the pilot valve device and the differential pressure cylinder device can be varied within the intended scope of the present invention. The present invention is not limited to the above embodiments.
[0022]
As for the predetermined additional external force means of the pilot valve device and the differential pressure cylinder device, in addition to the method of using an elastic member such as a spring as in each embodiment, for example, it is linked to a weight having a constant force, or further doubled. Needless to say, a force mechanism can be added, and an atmospheric pressure, hydraulic device, or the like can be easily applied. The sealing means for the pressure receiving plate 23 of the pilot valve device may be a bellows type or a O-ring or the like on the sliding surface of the pressure receiving plate in addition to the method using the diaphragm type sealing member 28 as in each embodiment. It may be applied to maintain watertightness. In each of the embodiments, a seal member is arranged at a place where it is desired to maintain water tightness. However, in the case of design and production capable of maintaining good water tightness by direct contact, it is of course possible to omit the seal member. is there.
[0023]
Regarding the structure of the main valve device, in each embodiment, a lift valve type is applied to the main valve body 5, but other types of opening / closing valves (for example, butterfly valves, Of course, gate valves, ball valves, etc.) may be applied. If the material of the main valve box 1 is appropriate for the formation of the cylinder, the cylindrical inner wall portion 8 can also be omitted by being shared by the main valve box 1. The main valve spring 7 is desirable in terms of the stability of the operation of the main valve body 5 at the time of the first water flow, but can be omitted because it is not particularly related to the subsequent operation. In each of the embodiments, in order to simplify the structure of the main valve device, both the main valve flow path part of a → b → c1 → c2 and the main valve drive pressure chamber d are compact in the main valve box 1. In addition, the main valve channel portion and the main valve driving pressure chamber d are accommodated in each of the main valve boxes divided into two, and the two valve boxes are penetrated. There may be a structure in which the main valve body 5 and the main valve drive member 6 are fixed to both ends of the main valve shaft.
[0024]
Depending on the specification conditions, it may be necessary to slowly operate the pilot valve device and main valve device to prevent pressure pulsation (hunting) due to unexpected flow changes during operation. As an example, FIG. 1 shows an example in which the shape of the main valve opening b is a serrated flow path that smoothes the flow rate change, and FIG. 2 shows that the main valve device is provided with a shock absorber 14. The example which provided the throttle valve in the middle of the secondary pressure communication path to the secondary pressure chamber i of a pilot valve apparatus is shown. In addition, although illustration is omitted, there is of course a method of providing a shock absorber in the pilot valve device. Any one of these countermeasures may be employed alone, or some may be employed in combination, or may be omitted under specification conditions where it is not required.
[0025]
For the orifice 12, a general on-off valve (for example, a butterfly valve, a gate valve, a ball valve, a lift valve, etc.) can also be applied. In addition, since the orifice 12 does not necessarily have a shut-off watertight performance, a seal with respect to the valve seat can be omitted. In addition to the manual operation by the handle 13, the operation can be driven by various actuators, and the driving procedure can be automated.
1 and 2 show an example in which the orifice 12 is arranged on the downstream side of the main valve. The installation position of the orifice 12 is basically either upstream or downstream of the main valve. It is good (the illustration of the installation on the upstream side of the main valve is omitted because it is obvious). The installation on the downstream side is desirable in that the pressure applied to the differential pressure cylinder device is relatively low and easy to design. On the other hand, the installation on the upstream side allows the operation of the differential pressure cylinder device to operate the main valve body 5. It is desirable in that it is less susceptible to the effects of waves associated with the operation of
1 and 2, when the spring force adjusting section 36 is provided on the spring 35 as the predetermined additional external force means of the differential pressure cylinder device, the adjustment of the predetermined additional external force, that is, the flow rate setting is performed. Therefore, it is not necessary to limit the flow rate adjustment by the orifice 12 throttle operation. That is, in this case, the flow rate is set only by the adjusting portion 36 of the predetermined additional external force means of the differential pressure cylinder device, and the orifice 12 may be a fixed orifice, and particularly due to turbulent flow when an on-off valve type orifice is mounted. This is effective when you want to suppress the occurrence of differential pressure detection error as much as possible.
[0026]
In both FIG. 1 and FIG. 2, a safety valve 11 suitable for the pipeline is mounted at an appropriate position on the outlet flow channel side for further safety management of the facility. This may be omitted if unnecessary.
In addition, over the members constituting the valve device of the present invention, the use of the prior art is not disturbed, and various design changes can be made within the scope of the present invention. It is not limited to.
[0027]
【The invention's effect】
In the automatic adjustment valve device according to the present invention, there is no fixed throttle channel such as a needle valve in the pilot valve device section, and each valve body of the valve device is appropriately opened to perform a self-cleaning operation. A maintenance-free valve device with no pressure clogging, perfect water tightness when water stops, and a pressure adjustment function that operates without causing an abnormal increase in secondary pressure during both water supply and water stoppages. Not only that, the amount of fluid supplied downstream can be automatically limited to a predetermined amount, which is very convenient. In addition, the structure of the pilot valve device is simple, the secondary pressure and flow rate can be easily set with a single touch, and there are no troublesome parts in design, production, operation and maintenance management, and automatic adjustment is highly reliable and economical. A valve device can be obtained, and its implementation effect is extremely large.
[Brief description of the drawings]
FIG. 1 is an overall longitudinal sectional view showing an embodiment of the present invention.
FIG. 2 is an overall longitudinal sectional view showing another embodiment of the present invention.
FIG. 3 is an overall longitudinal sectional view showing an example of a conventional automatic constant pressure valve device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Main valve box 2 ... Main valve box cover 3 ... Main valve seat 4 ... Main valve shaft 5 ... Main valve body 5s ... Seal member 6 ... Main valve drive member 6s ... Seal member 7 ... Main valve spring 8 ... Cylindrical inner wall Part 9 ... Bearing 10 ... Bearing 11 ... Safety valve 12 ... Orifice 13 ... Handle 14 ... Shock absorber 21 ... Pilot valve box 22 ... Pilot valve box cover 23 ... Pilot pressure receiving plate 24 ... A valve element 24s ... Seal member 25 ... B valve element 26 ... Pilot valve shaft 27 ... Spring 28 ... Seal member 29 ... Spring force adjustment part 30 ... Damping device 31 ... Differential pressure cylinder 32 ... Differential pressure cylinder lid 33 ... Piston 34 ... Piston shaft 35 ... Spring 36 ... Spring force adjustment part a ... Inlet channel b ... Main valve opening c (c1; c2) ... Outlet channel d ... Main valve drive pressure chamber e ... A valve chamber f ... A valve seat chamber g ... B valve chamber h ... B valve seat chamber i ... Secondary pressure chamber j ... Spring chamber u ... Orifice front pressure w ... orifice rear pressure chamber P ... communicating passage Pe ... communicating passage Q (Q1; Q2) ... communicating passage

Claims (2)

In a self-regulating valve device in which a main valve device is driven in conjunction with a pilot valve device operated by a change in pressure of fluid flowing through it,
The main valve device has a main valve body integrally incorporated in the main valve box and a main valve drive member having a larger pressure receiving area than the main valve body, and the main valve body is located upstream of the main valve seat. The throttle valve is formed between the main valve seat and the main valve drive member is slidably fitted to the cylindrical inner wall portion of the main valve box, and between the inner wall portion and the main valve seat. Forming the main valve drive pressure chamber,
The pilot valve device has a pilot A valve portion and a pilot B valve portion on the same axis, which are operated by a balance of the opposing acting force between the downstream pressure of the main valve device and the predetermined additional external force means, and on the downstream side of the main valve When the pressure is at a predetermined value, both remain substantially closed, and the pilot A valve portion that opens when the pressure on the downstream side of the main valve becomes lower than the predetermined value, and opens when the pressure on the downstream side of the main valve becomes higher than the predetermined value And the pilot B valve portion that communicates in series between the inlet passage and the outlet passage of the main valve device via the main valve driving pressure chamber in the middle,
A differential pressure cylinder device that operates by a balance between the opposing differential force of the front and rear differential pressures of the orifice provided in the flow path of the main valve device and the predetermined additional external force means is attached to the pilot valve device, and the orifice If the differential pressure before and after becomes higher than a predetermined value, the piston shaft of the differential pressure cylinder device pushes the valve shaft of the pilot valve device in a direction opposite to the force of the predetermined additional external force means of the pilot valve device. An automatic adjustment valve device characterized by that.   2. The automatic adjustment valve device according to claim 1, wherein the orifice is a variable orifice.

Images