JP2013108552A - Valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve that can be made compact so as to be usable as a portion (component) of a wireline/downhole tool, or the like.SOLUTION: A valve 10 includes a piston 16 and a valve body 12 having a piston hole 18 for accommodating the piston 16. The valve body 12 is provided with: a plurality of channels 20 that extend along the axial direction of the piston 16 and have openings 14; and a plurality of communicating passages 22 that respectively communicate with the channels 20 and communicate with the piston hole 18 at positions 24 different from one another in the axial direction. The piston 16 is provided with sealing members 28, 30, which seal between the piston 16 and the piston hole 18 and are arranged at an interval corresponding to the spacing of communicating portions of the piston hole 18 with the plurality of communicating passages 22. A gap is formed between the piston hole 18 and an outer surface of a portion 34 of the piston 16 between the sealing members 28, 30.

Description

  The present invention relates to a valve.

  Conventionally, a valve capable of switching a flow path in a plurality of directions is known. For example, Patent Document 1 proposes a valve capable of switching the air flow path in multiple directions. In the valve described in Patent Document 1, a piston provided in a cylinder connected to a plurality of flow paths can be moved to switch the connection of the flow paths. Moreover, as a valve which switches a flow path with a piston, there exists a valve currently used for BOP (spout prevention apparatus) of a deep-sea exploration ship as described in the nonpatent literature 1 and 2. FIG.

JP 2002-250455 A

“SPM Valve”, [online], Gilmore Valve Company, [searched on November 17, 2011], Internet <URL: http://www.gilmorevalve.com/products/smp_valves.asp> “Servo Valve”, [online], MOOG, [Searched on November 17, 2011], Internet <URL: http://www.moog.co.jp/english/products/servovalves-servo-proportional-valves/ >

  The axial direction of the piston of the valve described in the cited document 1 is perpendicular to the direction of the flow path through which fluid enters and exits the valve. A drive source for moving the piston is provided on one end side of the piston. Therefore, an area for moving the piston and an area for providing a drive source are required in the axial direction of the piston. In the valves described in Non-Patent Documents 1 and 2, the axial direction of the piston and the direction of the flow path through which fluid enters and exits the valve are perpendicular to each other.

  By the way, in the investigation of the seabed ground or the like, a valve for feeding a high-pressure fluid in a plurality of directions is required as a part (part) of a wireline downhole tool used in logging after excavating the ground. The valve as a part (part) of the wire line downhaul tool needs to be miniaturized because it is put in the excavated hole. However, in the configuration like the valve described in Patent Document 1, as described above, a region for moving the piston in a direction perpendicular to the flow path and a region for providing drive reduction are required, and thus the size is reduced. It is difficult. Further, even in the configuration such as the valve described in Non-Patent Documents 1 and 2, it is difficult to reduce the size because a region for moving the piston in the direction perpendicular to the flow path is required as described above.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a valve that can be miniaturized so that it can be used as a part (part) of a wireline downhole tool. .

  In order to achieve the above object, a valve according to the present invention is a valve comprising a piston and a valve body provided with a piston hole for movably housing the piston in the axial direction. Is a plurality of flow paths that extend along the axial direction of the piston and have an opening in the valve body and through which fluid can flow, and communicate with each of the flow paths and at different positions in the axial direction of the piston. The piston is provided with a plurality of communication passages that communicate with the piston hole, and the piston seals between the piston and the piston hole, and according to the interval between the communication portions of the piston hole with the plurality of communication passages. At least two seal members provided at a predetermined interval are provided, and there is a gap between the outer surface of the piston between the seal members and the piston hole. .

  In the valve of the present invention, when the piston is moved in the piston hole and the position sealed by the seal member changes, the communication path communicated by the gap between the positions where the seal member is provided is changed. The direction of the fluid can be controlled. In the valve of the present invention, since the direction in which the flow path extends in the valve body and the axial direction of the piston for controlling the direction of the fluid are the same direction, the size of the valve in the direction perpendicular to the direction is determined. Can be small. Thereby, the valve | bulb of this invention can be reduced in size so that it can be utilized as a part (parts) etc. of a wireline downhaul tool.

  The valve body piston hole may be provided with a groove in a communication portion with the communication passage. According to this configuration, the piston can be easily moved in the piston hole.

  Each of the plurality of communication paths may be connected to the piston hole at an angle of 30 degrees to 70 degrees. According to this configuration, the fluid in the valve can easily flow.

  Each of the plurality of communication paths may have a configuration in which a hole penetrating the outer surface of the valve body and the hole for the piston is closed with a plug in which an opening on the outer surface side of the valve body is welded. According to this configuration, the communication path can be easily configured and can withstand the pressure of the fluid in the valve.

  It is good also as a hollow being provided between the sealing members in a piston. According to this configuration, the fluid can easily flow in the piston hole.

  The seal member may include an O-ring and backup rings provided on both sides of the O-ring. According to this configuration, the seal member can be configured easily and reliably.

  The piston may be subjected to a surface treatment that improves low wear and hardness. According to this configuration, it is possible to configure a valve that can be used even in a high-pressure and high-temperature environment.

  The valve may further include a drive unit that moves the piston in the axial direction. According to this structure, a piston can be moved and it can function as a valve reliably.

  The drive unit may be a stepping motor that moves the piston via a lead screw. According to this configuration, the piston can be moved reliably and instantaneously and the valve can be downsized.

  In the valve of the present invention, when the piston is moved in the piston hole and the position sealed by the seal member varies, the communication path communicated between the positions where the seal member is provided is changed, and the fluid The direction can be controlled. In the valve of the present invention, since the direction in which the flow path extends in the valve body and the axial direction of the piston for controlling the direction of the fluid are the same direction, the size of the valve in the direction perpendicular to the direction is determined. Can be small. Thereby, the valve | bulb of this invention can be reduced in size so that it can be utilized as a part (parts) etc. of a wireline downhaul tool.

It is a perspective view of the valve | bulb which concerns on embodiment of this invention. It is the top view, sectional drawing, and bottom view of a valve concerning an embodiment of the present invention. It is a figure which shows the surface in which the opening part of the valve main body was provided. It is a figure for demonstrating the process of the part in which the plug of a valve body is provided, and a welding plug. It is a figure which shows the piston used for a valve. It is a figure which shows typically operation | movement of the valve | bulb which concerns on embodiment of this invention.

  Hereinafter, preferred embodiments of a valve according to the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the dimensional ratios in the drawings do not necessarily match those described.

  FIG. 1 shows a valve (valve mechanism) 10 according to this embodiment. 2A is a top view of the valve 10, FIG. 2B is a cross-sectional view of the valve 10, and FIG. 2C is a bottom view of the valve 10. The valve 10 is used, for example, for excavation of the ground (inserted into a drilling hole) or the like as a part (part) of a wireline downhole tool. The valve 10 is a multi-directional valve, for example, provided with a plurality of fluid discharge ports, and switches the discharge port of the fluid that has flowed into the valve 10. When the valve 10 is used as a part (component) of a wire line downhaul tool for surveying the seabed ground, the fluid flowing into the valve 10 is a very high pressure fluid of 150 MPa. In such a case, the environment in which the valve 10 is used is a high pressure (for example, 150 MPa) and a high temperature (for example, 150 ° C.).

  The valve 10 includes a cylindrical valve body 12. The valve body 12 is formed of a metal having sufficient hardness as the valve 10. For example, a stainless steel material is used. The valve body 12 is provided with a plurality of openings 14 serving as fluid inlets and outlets. The valve 10 shown in the present embodiment is provided with one opening 14a on one surface of a cylindrical valve body 12 and two openings 14b and 14c on the other surface. The surfaces on which the openings 14a, 14b, and 14c are provided are perpendicular to the axial direction of the piston 16 included in the valve 10 as will be described later. The valve 10 discharges the fluid that has flowed into the opening 14a from one of the openings 14b and 14c. FIG. 3A shows the surface of the valve body 12 in which the opening 14a is provided (the left side of the valve body 12 in FIG. 2), and FIG. 3B shows that the openings 14b and 14c in the valve body 12 are provided. The surface (the right surface of the valve body 12 in FIG. 2) is shown.

  As illustrated in FIG. 2B, the valve 10 includes a piston (piston cylinder) 16 that is accommodated in the valve body 12. The valve body 12 is provided with a piston hole 18 for accommodating the piston 16 so as to be movable in the axial direction A. The piston hole 18 has a cross-sectional shape similar to the cross-sectional shape (specifically circular) of the thickest portion of the piston 16, and the cross-sectional size is larger than that of the thickest portion of the piston 16. Is also slightly larger. That is, the inner circumference constituting the piston hole 18 is slightly larger than the diameter of the thickest portion of the piston 16. As a result, the piston 16 accommodated in the piston hole 18 can move only in the axial direction A (the left direction and the right direction in FIG. 2). The piston hole 18 also serves as a fluid passage as will be described later.

  Inside the valve body 12, a plurality of flow paths 20a, 20b, and 20c are provided that extend along the axial direction of the piston 16 and allow fluid to flow. A cross section perpendicular to the axial direction A of each of the flow paths 20a, 20b, and 20c is a circle having a smaller diameter than the piston hole 18. The diameter of each flow path 20a, 20b, 20c can be determined as appropriate according to the application of the valve 10. For example, when used as a part (component) of the above-described wireline downhole tool, the diameter of each of the flow paths 20a, 20b, and 20c can be reduced (for example, about 5 mm or less).

  These flow paths 20a, 20b, 20c have openings 14a, 14b, 14c in the valve body 12 at one end. As shown in FIG. 3, the positions of the openings 14 a, 14 b, and 14 c are respectively provided at different positions in the circumferential direction of the cylindrical valve body 12. Yes. Specifically, when viewed in the direction of FIG. 3A, the flow path 20a is at a position above the piston hole 18, and the flow path 20b is at a lower right position of the piston hole 18 (FIG. 3B). The flow path 20c is located at the lower left position of the piston hole 18 (lower right position when viewed in the direction of FIG. 3B). It extends along the axial direction of the piston hole 18).

  In addition, since the figure of FIG.2 (b) is a cross section along the flow path 20a, only the flow path 20a is shown, However, The flow paths 20b and 20c are provided in another position. 2 has an opening 14a on the left side of the valve body 12 in FIG. 2, but the flow paths 20b and 20c have openings 14b and 14c on the right side of the valve body 12 in FIG. ing.

  Further, the valve body 12 is provided with a plurality of communication passages 22a, 22b, and 22c that can communicate with each of the flow paths 20a, 20b, and 20c and that can communicate with the piston hole 18 and allow fluid to flow therethrough. . Each of the communication passages 22a, 22b, and 22c is provided at a position similar to the position of the communication passages 22a, 22b, and 22c in the circumferential direction of the valve body 12 (see, for example, FIG. 2B). Further, each of the communication passages 22a, 22b, and 22c extends in the radial direction of the valve body 12 from the inner periphery of the piston hole 18, and is an end portion that is not on the side of the openings 14a, 14b, and 14c of the flow paths 20a, 20b, and 20c. Communicated with. The communication passages 22a, 22b, and 22c have, for example, a circular shape with a cross section having the same diameter as the flow paths 20a, 20b, and 20c.

  Further, the communication passages 22a, 22b, and 22c are connected to the passages 20a, 20b, and 20c at an angle exceeding 90 degrees toward the piston hole 18 so that the fluid flowing in the valve 10 can easily flow. It is desirable that the angle θ1 shown in FIG. Similarly, the communication passages 22a, 22b, and 22c are connected to the piston hole 18 at an angle, more specifically, at an angle of 30 to 70 degrees (the angle shown in FIG. 2B). It is desirable that θ2 be 30 degrees to 70 degrees. In the example of this embodiment, the communication paths 22a, 22b, and 22c are connected to the piston hole 18 at an angle of 45 degrees in consideration of design space.

  Further, each of the flow paths 20 a, 20 b, 20 c communicates with the piston hole 18 at a position different from each other in the axial direction A of the piston 16. The communication positions 24a, 24b, and 24c between the flow paths 20a, 20b, and 20c and the piston hole 18 are respectively the communication position 24b, the communication position 24a, and the communication position 24c in order from the right side in the positional relationship shown in FIG. It is in order. That is, here, the communication position 24a of the communication path 22a for allowing the fluid to flow in is located between the communication positions 24b and 24c of the communication paths 22b and 22c for discharging the fluid. The intervals between the communication positions 24a, 24b, and 24c are substantially the same, and a seal member provided between the communication positions 24a, 24b, and 24c and the piston 16 is provided between the communication positions 24a, 24b, and 24c as described later. It is wide enough to seal between the piston hole 18.

  Further, each communication position (communication portion) 24a, 24b, 24c in the piston hole 18 of the valve body 12 is provided with a groove (concave portion), and the diameter of the piston hole 18 in this portion is larger than that of other portions. Slightly larger. In addition, the groove | channel provided in the hole 18 for pistons may be provided over the inner periphery of the hole 18 for pistons, and may be provided only in the communication part 24 of the communication path 22. FIG. This is because, as will be described later, since the piston 16 has a thick part and a thin part, the piston 16 is prevented from being caught at the communication positions 24a, 24b, 24c when moving in the piston hole 18. It can be moved smoothly. Further, it is desirable that the edge of the communication portion 24 of the communication path 22 has a curvature so as to eliminate damage to the piston 16 and a seal member described later.

  The communication passages 22a, 22b, and 22c are formed by opening holes that penetrate from the outer peripheral surface of the valve body 12 to the piston hole 18 and closing the openings on the outer peripheral surface side of the valve main body 12 with plugs 26a, 26b, and 26c. It is good as well. The plugs 26a, 26b, and 26c may be made of the same material as the valve body 12. The plugs 26a, 26b, and 26c are preferably joined to the valve body 12 by welding. Specifically, the welding can be electronic welding (EBW). In this case, as shown in FIG. 4, the valve body 12 is formed with a large diameter in advance, the plug 26 is joined by electronic welding, and then the surface of the valve body 12 is shaved so that the plug 26 is joined. 12 may be formed. With the above configuration, the communication paths 22a, 22b, and 22c can be easily configured and can withstand the pressure of the fluid in the valve 10. The welding may be other than electronic welding, for example, TIG welding.

  5 (a) is a left side view of the piston 16, FIG. 5 (b) is a front view of the piston 16, FIG. 5 (c) is a right side view of the piston 16, and FIG. 5 (d) is an axial view of the piston 16. A sectional view along is shown. The piston 16 is an elongated cylindrical member, and has a length exceeding at least the distance between the communication positions 24a, 24b, and 24c.

  The piston 16 seals between the piston 16 and the piston hole 18 and is provided with at least two seals provided at intervals corresponding to the intervals of the communication portions 24a, 24b, and 24c with the plurality of communication paths in the piston hole 18. A member is provided. Specifically, each seal member includes an O-ring 28 and two backup rings 30 provided on both sides of the O-ring 28. An annular groove (concave portion) 32 is provided in a portion (position in the axial direction A) where the O-ring 28 and the two backup rings 30 of the piston 16 are provided, and the O-ring 28 and the two backup rings 30 are provided in the groove. A backup ring 30 is accommodated.

  A portion 34 between the two seal members 28a and 30a (inside of the four) in the piston 16 has a diameter (thickness) such that a gap is formed between the outer peripheral surface of the piston 16 and the piston hole. ). A fluid flows in this gap as will be described later. Therefore, it is desirable that the portion 34 has a smaller diameter (thinner) than the other portion of the piston 16 so that fluid can easily flow, that is, the portion is provided with a recess. In order to facilitate fluid flow, both end sides 34a of the narrowed portion 34 of the piston have a tapered shape that increases as it approaches the portion where the two seal members 28a and 30a are provided. It is desirable.

  Seal members 28b and 30b may be further provided outside the portions where the seal members 28a and 30a on both sides of the recessed portion 34 of the piston 16 are provided. This is to more reliably seal between the piston 16 and the piston hole 18 and prevent the fluid from flowing into the communication path 22 where the fluid does not flow.

  The interval between the two seal members 28a, 30a is configured to be larger than the interval between the two continuous communication positions 24c, 24a or the communication positions 24a, 24b in the piston hole 18. Thus, when the right seal members 28a and 30a of the piston 16 are on the left side of the right communication position 24b (the state shown in FIG. 2B), the communication path 22a and the communication path 24c are connected to the piston 16 It will be in the state connected via the hollow part 34 (state which a fluid can flow). Further, when the left seal members 28a and 30a of the piston 16 are on the right side of the left communication position 24c, the communication path 22a and the communication path 24b are connected via the recessed portion 34 of the piston 16. (A state in which fluid can flow).

  The piston 16 needs a high-strength material. For example, a titanium alloy that is a corrosion-resistant, high-strength material is used. Further, as described above, since the piston 16 has the narrowed portion 34, the surface treatment for improving the low wear and altitude is performed so that the valve operates properly even under a high temperature and high pressure environment. desirable. Specifically, fine particles of a material suitable for the purpose are mixed with a compressible gas and collided at a high speed to form a fine, tough and dense structure that reinforces the surface and improves frictional wear characteristics. A treatment applied to the surface of the material is preferably performed.

  As a material for the O-ring 28, for example, fluororubber is used. As a material of the backup ring 30, for example, a plastic such as Teflon is used. Further, in the above-described high pressure and high temperature environment, for example, it is desirable to use an O-ring 28 having a pressure of 150 MPa and a hardness of 90D.

  The valve 10 may further include a drive unit that moves the piston 16 in the axial direction A. Specifically, the valve body 12 has an opening for the piston hole 18 on one side (the right side surface of the valve body 12 in FIG. 2) side through a bracket (cylinder shaft cover) 36 as a drive unit. A stepping motor 38 is attached on the axial direction A of the piston 16. The bracket 36 is screwed and fixed to the surface of the valve body 12, and the stepping motor 38 is screwed to the bracket 36 and fixed.

  The piston 16 is connected to a lead screw 40 that is axially aligned with the piston 16, and the lead screw 40 is connected to be rotated by a stepping motor (geared motor, pulse motor) 38. The bracket 36 is provided with a hole communicating with the piston hole 18 of the valve body 12, and the piston 16 and the lead screw 40 are disposed in the hole 36. Further, a ball bearing is connected to the lead screw 40 to constitute a ball screw structure. When the stepping motor 38 rotates the lead screw 40, the piston 16 can move back and forth in the axial direction A. Further, the stepping motor 38 is integrated with the speed reducer.

  By adopting such a ball screw structure, for example, even when sealing is performed with an O-ring 28 having a pressure of 150 MPa and a hardness of 90D, a sufficient driving force is obtained. Moreover, the piston 16 can be moved instantaneously by taking such a structure. This makes it possible to open and close the fluid and change the flow path instantaneously (over 1 second). It can also be opened and closed over time.

  In order to reduce space, it is preferable to use a hollow type stepping motor 38 in which a ball screw can be passed through the center of the motor as shown in FIG. Since the cavity is provided in the center of the stepping motor 38, the connection relationship between the reduction gear and the stepping motor 38 can be reduced. Further, it is desirable to use a stepping motor 38 that can handle a high temperature with a maximum environmental temperature of 150 ° C., for example. Further, the stepping motor 38 is operated by an external control signal. A stopper may be provided in the valve 10 so that the piston 16 does not move beyond a predetermined range when the piston 16 is moved by the stepping motor 38, or in order to position the piston 16. .

  In addition, as shown in FIG. 2, a pipe 42 for passing a fluid flowing into the valve 10 or a fluid discharged from the valve 10 may be connected to the opening 14 of the valve body 12.

  Subsequently, the operation of the valve 10 according to the embodiment of the present invention will be described with reference to FIG. 6 schematically shows a cross section of the valve 10 in order to make the operation easy to understand (in the valve shown in FIG. 2, the flow paths 20a, 20b, and 20c are not located on the same cross section as in FIG. However, the flow paths 20a, 20b, and 20c may be arranged on the same cross section as shown in FIG.

  First, when the piston 16 is located at the position (center) shown in FIG. 6A, the fluid that has flowed into the flow path 20a from the opening 14a passes through the communication path 22a and enters the piston hole 18. It flows into the part 34 between the sealing members of the piston 16. Since both sides of the portion 34 are sealed with a sealing member, the fluid passes around the portion 34 of the piston 16 and flows into the communication passage 22b, and is discharged from the opening 14b through the flow path 20b. The That is, in this case, there is a flow line through which the fluid passes in the order of the flow path 20a, the communication path 22a, the piston hole 18, the communication path 22b, and the flow path 20b.

  On the other hand, when the piston 16 is positioned at the position (left side) shown in FIG. 6B, the fluid that has flowed into the flow path 20a from the opening 14a passes through the communication path 22a and passes through the piston hole 18. At a portion 34 between the sealing members of the piston 16. Since both sides of the portion 34 are sealed with a sealing member, the fluid passes around the portion 34 of the piston 16 and flows into the communication passage 22c, and is discharged from the opening 14c through the flow path 20b. The That is, in this case, a flow line different from the case of FIG. 6A in which the fluid passes in the order of the flow path 20a, the communication path 22a, the piston hole 18, the communication path 22c, and the flow path 20c is formed.

  Thus, the flow line (fluid flow) can be instantaneously changed by moving the piston 16 back and forth in the axial direction by the drive unit.

  In the valve 10 according to the present embodiment, as described above, the seal member 28, 30 is provided by moving the piston 16 in the piston hole 18 and changing the position sealed by the seal member 28, 30. The communication path 22 communicated with the gap between the determined positions is changed, and the direction of the fluid can be controlled. In the valve 10 according to the present embodiment, the direction in which the flow path 20 extends in the valve body 12 and the axial direction of the piston 16 for controlling the direction of the fluid are the same direction. The size in the vertical direction can be reduced. That is, the size of the valve 10 (valve body 12) in the radial direction can be reduced, and a small-diameter valve 10 can be realized. For example, in the example of the valve 10 of the present embodiment described above, the valve 10 having a diameter of 100 mm or less can be realized.

  Thereby, the valve | bulb 10 which concerns on this embodiment can be put into comparatively small holes, such as an excavation hole, and can be utilized as a part (parts) etc. of a wireline downhaul tool. Specifically, it can be used to investigate the pressure of the seabed ground.

  Further, as described above, the valve 10 according to the present embodiment has a small number of parts, and therefore does not require a special tool for assembly, and has good maintainability. Moreover, there are few replacement parts and it is excellent also in economical efficiency. Further, as described above, it is possible to configure so that the number of damaged portions is reduced.

  Further, as in the present embodiment, it is desirable that the piston hole 18 of the valve body 12 is provided with a groove in the communication portion 24 with the communication passage 22. According to this configuration, the piston 16 and the sealing members 28 and 30 provided on the piston 16 are prevented from being caught by the communication portion 24 when moving, and the piston 16 can be easily moved in the piston hole 18. Can do.

  Further, as in the present embodiment, it is desirable that the communication path 22 is connected obliquely to the piston hole 18. Specifically, it is desirable to be connected at an angle of 30 degrees to 70 degrees. According to this configuration, the fluid in the valve 10 can be easily flowed. In particular, even if the fluid is a liquid having a relatively high viscosity, it can be made easy to flow.

  Further, as in the present embodiment, it is desirable that the communication path 22 has a configuration in which the opening on the outer surface of the valve body 12 is closed with a plug welded (electronic welding, TIG welding, etc.). According to this configuration, the communication path 22 can be easily configured and can withstand the pressure of the fluid in the valve 10.

  In addition, a recess may be provided in the portion 34 between which the fluid in the piston 16 passes and the seal members 28a and 30a are provided. According to this configuration, the space in which the fluid can flow in the piston hole 18 is widened, and the fluid can be easily flowed.

  Further, as in the present embodiment, the sealing member may include an O-ring 28 and a backup ring 30 provided on both sides of the O-ring 28. According to this configuration, the seal member can be configured easily and reliably. However, it is sufficient that the space between the piston 16 and the piston hole 18 can be sealed, and the configuration other than the above may be adopted as the sealing member.

  Further, according to this configuration in which the piston 16 is subjected to a surface treatment that improves low wear and hardness, it is possible to configure the valve 10 that can be used even in a high-pressure and high-temperature environment.

  Moreover, it is desirable to provide the stepping motor 38 which is a drive part which moves the piston 16 to the axial direction A like this embodiment. According to this configuration, the piston can be moved instantaneously and can function reliably and instantaneously as a valve. Further, the valve 10 can be reduced in size by using the stepping motor 38 that passes the lead screw 40 through the center. In addition, as long as the drive part can move the piston 16, things other than the structure mentioned above may be used. For example, a system that can be opened and closed instantaneously in the following cases is required. When water pressure is used to make a crack in the inner wall of a borehole drilled in the ground, high water pressure is required. As a scientific investigation, it is necessary to stop the flow of fluid instantaneously and measure it. When the fluid pressure in the borehole is changed and the hydraulic characteristics (permeability, etc.) of the formation are estimated from the subsequent fluid pressure change, if the changed fluid pressure change is not instantaneous, the subsequent fluid pressure change is affected. Moreover, in the stress measurement by hydraulic crushing, since the crushing is performed by the fluid pressure and the stress is calculated from the fluid pressure change at that time, instantaneous fluid pressure control is required.

  The valve 10 described above has three openings 14 through which fluid flows in or out. However, the valve 10 may have four or more openings. That is, it may be configured as a switching valve for four or more directions instead of the three-way valve. Also in this case, the connecting portion 24 between the communication passage 22 communicating with the opening 14 and the piston hole 18 is arranged shifted in the axial direction A, and the piston and the piston are connected by the seal member according to the position of the piston 16. By sealing between the holes 18, the flow line (fluid flow) can be switched.

  Further, in the present embodiment, the discharge ports 14b and 14c for the fluid flowing into the valve 10 are switched. However, a plurality of inlets may be provided to switch the inlets that can flow into the valve 10. .

  The valve of the present invention is used in the environment (for example, gas / steam / hydro turbine, oil refinery plant, natural gas processing plant, thermal / hydro power plant, steam power plant, geothermal power plant, nuclear power plant, nuclear reprocessing plant, mud water. Plant, deep sea water plant, vacuum transportation plant, water and sewage, subsea equipment (for seafloor installation)), science (eg underground exploration equipment, high temperature and high pressure test tank), transportation (eg automobile (fuel control, suspension, etc.)) , Ship, aircraft, submarine, railway), manufacture (eg plastic molding, robot, injection molding, metal molding, water jet), medical (eg rescue pressure mat), semiconductor (eg semiconductor plant), food (eg Application in fields such as food plant and soft ice cream manufacturing equipment).

DESCRIPTION OF SYMBOLS 10 ... Valve, 12 ... Valve body, 14 ... Opening part, 16 ... Piston, 18 ... Piston hole, 20 ... Flow path, 22 ... Communication path, 26 ... Plug, 28 ... O-ring, 30 ... Backup ring, 36 ... Bracket, 38 ... stepping motor, 40 ... lead screw, 42 ... piping.

Claims (9)

A valve comprising a piston and a valve body provided with a piston hole for accommodating the piston movably in the axial direction,
The valve body has a plurality of flow paths that extend along the axial direction of the piston and have an opening in the valve main body and allow fluid to flow, and communicate with each of the flow paths and the axial direction of the piston. And a plurality of communication passages communicating with the piston hole at different positions in FIG.
The piston is provided with at least two seal members that seal between the piston and the piston hole and are provided at intervals according to the intervals of the communication portions with the plurality of communication paths in the piston hole.
The valve which has a clearance gap between the outer surface between the said sealing members in the said piston, and the said hole for pistons.   The valve according to claim 1, wherein the piston hole of the valve body is provided with a groove in a communication portion with the communication path.   The valve according to claim 1 or 2, wherein each of the plurality of communication passages is connected to the piston hole at an angle of 30 degrees to 70 degrees.   Each of the plurality of communication passages has a structure in which a hole penetrating the outer surface of the valve body and the hole for the piston is closed with a welded plug on the outer surface side of the valve body. The valve according to any one of the above.   The valve according to any one of claims 1 to 4, wherein a recess is provided between the seal members of the piston.   The valve according to any one of claims 1 to 5, wherein the seal member includes an O-ring and a backup ring provided on both sides of the O-ring.   The valve according to any one of claims 1 to 6, wherein the piston is subjected to a surface treatment for improving low wear and hardness.   The valve according to any one of claims 1 to 7, further comprising a drive unit that moves the piston in an axial direction. The valve according to claim 8, wherein the driving unit is a stepping motor that moves a piston via a lead screw.

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