JP2015052366A - Pilot type valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce resisting force acting against a main valve member when the main valve member moves in the pilot type valve device.SOLUTION: In this invention, a housing 5 of a valve device 1 includes a main flow passage 50, a main valve chamber 53, a pilot flow passage 60 and a pilot valve chamber 56. A pilot valve member 41 for opening or closing the pilot flow passage 60 is arranged in the pilot valve chamber 56. A main valve member 31 for opening or closing the main flow passage 50 is arranged in the main valve chamber 53 so as to separate the main valve chamber 53 into the first area 58 communicated with the first flow passage 51 and the second area 59 communicated with the pilot flow passage 60. There is provided an elastic film 34 arranged between the housing 5 and the main valve member 31 so as to separate the first area 58 from the second area 59. The main valve member 31 is supported by a valve supporting part in the housing 5 under a non-contact with the wall of the main valve chamber 53 and in such a manner as it may be movable in its opening or closing direction.

Description

  The present invention relates to a pilot valve device for gas.

  Conventionally, a pilot type valve device that operates a pilot valve by electromagnetic force or the like and opens and closes the main valve by a pressure difference between the main valve body upper pressure and the inlet pressure is known. For example, Patent Document 1 discloses a main valve (shutoff valve) that is provided in a flow path connecting a primary port and a secondary port and opens and closes by a differential pressure between a fluid inlet pressure and a back pressure, and an operation pressure applied to the main valve. A pilot-type valve device having a pilot valve that generates a lead differential pressure and a differential pressure valve that maintains a constant difference between the primary pressure and the secondary pressure by changing the opening when the main valve is opened is shown. Yes.

  In the pilot type valve device, the first pressure chamber, the second pressure chamber, and the back pressure chamber of the main valve are formed by providing a seal member between the main valve body and the housing. In paragraph 0038 of Patent Document 1, the sliding force between the main valve body and the housing is taken into consideration in the driving force applied to the main valve, and the main valve body and the housing are included in this sliding resistance force. It is described that it originates in the sealing member between.

JP 2004-278627 A

  As described above, the seal member that seals the fluid is provided between the main valve body and the housing, but the friction between the main valve body and the seal member is the sliding resistance force when the main valve body moves. Become. Therefore, in the pilot type valve that opens and closes with the differential pressure of the fluid, the differential pressure for opening and closing the main valve element increases due to the sliding resistance. Further, when trying to move the stationary main valve body, a static frictional force is generated between the main valve body and the seal member. Due to this static frictional force, the pressure difference (minimum operating differential pressure) necessary for stable operation of the main valve element increases. If the minimum operating differential pressure increases, the time from when the pilot valve switches until the differential pressure acting on the main valve body reaches the minimum operating differential pressure and the valve moves, that is, the valve response time becomes longer, and the valve response Sex is reduced.

  Further, since there is a gap between the main valve body and the housing, the main valve body is eccentric in the housing. If the main valve body slides eccentrically with respect to the housing, the seal member may be unevenly worn. When the partial wear of the seal member increases, the main valve body and the housing slide directly, and the movement of the main valve body is galling. Thereby, the operation of the valve becomes unstable.

  In particular, when the fluid is gas, the main valve body slides on the seal member, so wear of the seal member is inevitable. Since the fluid cannot be sealed when the seal member wears, the seal member must be frequently replaced.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to stabilize the valve opening / closing operation by reducing the resistance force acting on the main valve body during movement of the main valve body in the pilot valve device. The purpose is to improve the responsiveness of the valve opening / closing operation and the durability of the valve.

The pilot type valve device of the present invention is
A main flow path composed of a primary flow path and a secondary flow path, a main valve chamber formed between the primary flow path and the secondary flow path, the secondary flow path and the A pilot channel connecting the main valve chamber, and a housing having a pilot valve chamber formed in the pilot channel;
A pilot valve body disposed in the pilot valve chamber to open and close the pilot flow path;
The main valve chamber is disposed in the main valve chamber so as to partition the first valve chamber into a first region communicating with the primary flow path and a second region communicating with the pilot flow path, and the first region and the first A main valve body that opens and closes the main flow path in accordance with a differential pressure of fluid with respect to the two regions;
A valve body support provided in the housing and supporting the main valve body in a non-contacting manner with a wall of the main valve chamber and being movable in an opening and closing direction;
An urging member for urging the main valve body in an opening / closing direction closing direction;
An elastic membrane is provided between the housing and the main valve body and separates the first region and the second region.

  In the pilot-type valve device, the main valve body may have a shaft-shaped portion extending in the opening / closing direction, and the valve body support portion may have an opening into which the shaft-shaped portion of the main valve body is inserted. . Or the said valve body support part may have an axial shape part extended in the said opening-and-closing direction, and the said main valve body may have an opening part in which the said axial shape part of the said valve body support part is inserted. Or the said valve body support part may be provided in the inner periphery of the said main valve chamber.

  Further, in the pilot valve device, the elastic membrane has an annular shape, an inner peripheral edge portion coupled to the main valve body, an outer peripheral edge portion coupled to the wall of the main valve chamber, and the inner peripheral portion. You may have the elastic deformation part bent to the said 2nd area | region side between the peripheral part and the said outer peripheral part.

  According to the pilot type valve device having the above-described configuration, the first region and the second region are separated by the elastic film, and this elastic film can be elastically deformed following the movement of the main valve body. Therefore, the movement of the main valve body is not hindered by the means for separating the first region and the second region. Therefore, compared to the conventional case where the first region and the second region are separated by a seal member sandwiched between the main valve body and the housing, the resistance force acting on the main valve body when the main valve body moves is reduced. Can be reduced. Furthermore, since a worn seal member is not interposed between the main valve body and the housing, the durability of the valve can be improved.

  It is desirable that the pilot valve device further includes a direct acting bearing provided between the main valve body and the valve body support portion. The linear motion bearing may be a rolling bearing. Alternatively, the linear motion bearing may be a sliding bearing.

  According to the pilot type valve device having the above configuration, the housing and the main valve body are not in direct contact with each other, and the main valve body is supported by the housing via the direct acting bearing. The kinetic friction and static friction between the two are generally zero or sufficiently small compared to the case without the linear motion bearing. Therefore, the sliding resistance between the main valve body and the housing is substantially zero or sufficiently smaller than the case where there is no direct acting bearing, so that the resistance force acting on the main valve body when the main valve body moves is reduced. Can be reduced.

  It is desirable that the pilot valve device further includes a backing member that contacts the second region side of the elastic membrane and moves with the main valve body. The backing member may have a ring shape and a curved shape in which a radial cross section of a portion in contact with the elastic film is convex toward the second region. In addition, a seat for holding the biasing member may be integrally formed with the backing member.

  According to the pilot type valve device configured as described above, the elastic membrane coupled to the main valve body is deformed while being in contact with the backing member when the main valve body is moved, thereby preventing the elastic membrane from being damaged. Thereby, the pressure resistance and durability of the elastic membrane are improved.

  The pilot valve device further includes a pair of sealing members disposed so as to sandwich the linear motion bearing from the opening / closing direction, and a lubricant filled between the pair of sealing members. It is desirable.

  According to the pilot type valve device having the above configuration, the direct acting bearing is lubricated, so that the durability of the direct acting bearing is improved and the operation of the direct acting bearing is smoothed, and the main valve body is moved. Sometimes the resistance force acting on the main valve body can be further reduced.

  According to the present invention, it is possible to reduce the resistance force acting on the main valve body when the main valve body moves. As a result, an increase in the differential pressure required when the valve is opened can be avoided, contributing to stabilization of the valve opening / closing operation and improvement of responsiveness. Further, since a member (for example, a seal member) that wears between the main valve body and the housing is not interposed, the durability of the valve is improved.

It is sectional drawing which shows the pilot type valve apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the main valve at the time of closure. It is sectional drawing which shows the main valve at the time of opening. It is sectional drawing which shows the main valve which concerns on the modified example 1-1 of embodiment of this invention. It is sectional drawing which shows the main valve which concerns on the modification 1-2 of embodiment of this invention. It is sectional drawing which shows the main valve which concerns on the modification 2 of embodiment of this invention. It is sectional drawing which shows the main valve which concerns on the modification 3-1 of embodiment of this invention. It is sectional drawing which shows the main valve which concerns on the modification 3-2 of embodiment of this invention. It is sectional drawing which shows the main valve which concerns on the modification 3-3 of embodiment of this invention. It is sectional drawing which shows the main valve which concerns on the modification 4-1 of embodiment of this invention. It is sectional drawing which shows the main valve which concerns on the modification 4-2 of embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a cross-sectional view showing a pilot type valve device (hereinafter simply referred to as “valve device 1”) according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing a main valve 3 when closed, and FIG. It is sectional drawing which shows the main valve 3. In FIG. 1, hatching indicating a cross section is omitted.

  As shown in FIGS. 1 to 3, the valve device 1 according to the present embodiment includes a housing 5 in which a fluid flow path is formed, and a main valve 3 and a pilot valve 4 provided in the housing 5. . The valve device 1 is provided, for example, in a flow path through which a compressible gas flows from the primary side to the secondary side, and is used to open and close the flow path.

  In the housing 5 of the valve device 1, a main channel 50 constituted by a primary side channel 51 and a secondary side channel 52, and a main channel formed between the primary side channel 51 and the secondary side channel 52 are formed. A valve chamber 53, a pilot channel 60 composed of a first pilot channel 54 and a second pilot channel 55, and a pilot valve chamber 56 formed in the pilot channel 60 are provided.

  The main flow path 50 is provided with a main valve 3 that opens and closes the main flow path 50. The main valve 3 includes a main valve element 31 disposed in the main valve chamber 53. The main valve body 31 partitions the main valve chamber 53 into a first region 58 communicated with the primary side flow path 51 and a second region 59 communicated with the pilot flow path 60. The second region 59 of the main valve chamber 53 is connected to the secondary channel 52 by the pilot channel 60. The pilot flow path 60 is provided with a pilot valve 4 that opens and closes the pilot flow path 60. The pilot valve 4 includes a pilot valve body 41 disposed in the pilot valve chamber 56. Hereinafter, the main valve 3 and the pilot valve 4 will be described in detail.

  First, the main valve 3 will be described. The main valve body 31 of the main valve 3 is loosely inserted into the main valve chamber 53. That is, there is a gap between the inner periphery of the main valve chamber 53 and the outer periphery of the main valve body 31, and the main valve body 31 is not in direct contact with the wall of the main valve chamber 53. A main valve portion 31 a is provided at one end (hereinafter referred to as “tip”) of the main valve body 31. The main valve portion 31 a can be seated on a main valve seat portion 47 provided between the main valve chamber 53 of the housing 5 and the secondary side flow path 52. The main valve body 31 has a direction in which the main valve portion 31a approaches the main valve seat portion 47 (hereinafter referred to as “closed direction (closed direction)”), and a direction in which the main valve portion 31a moves away from the main valve seat portion 47 (hereinafter, referred to as “closed direction”). It is possible to move in the opening and closing direction.

  The main valve body 31 has a cylindrical shape in which the tip is closed and the end opposite to the tip and the opening / closing direction (hereinafter referred to as “rear end”) is opened. In other words, the rear end of the main valve body 31 is provided with an opening 31c into which a valve body support portion 35a of a support body 35 described later is inserted. The main valve body 31 is formed with a flow path 31b that communicates the inner peripheral side and the outer peripheral side of the cylinder, and a throttle 32 is provided in the flow path 31b.

  A support 35 is inserted into the main valve chamber 53 so as to face the rear end of the main valve body 31. A seal member 36 that seals the outer periphery of the support 35 and the inner periphery of the main valve chamber 53 is provided on the outer periphery of the support 35. The support 35 is pressed in the closing direction by a lid 81 screwed into the main valve chamber 53 in order to seal the main valve chamber 53. Thus, the support 35 is fitted in the main valve chamber 53 so as not to move with respect to the housing 5.

  The support body 35 includes a first spring seat 35b provided on the facing surface spaced from the main valve body 31, and an axial valve body support portion projecting in the opening and closing direction from the facing surface toward the main valve body 31. 35a. The valve body support portion 35 a of the support body 35 has a function of supporting the main valve body 31 as a part of the housing 5. The valve body support portion 35 a is inserted from the rear end of the main valve body 31 into the opening 31 c of the main valve body 31.

  A direct acting bearing 38 is provided between the valve body support 35 a and the opening 31 c of the main valve body 31. The direct acting bearing 38 slides the main valve body 31 in the opening / closing direction with respect to the valve body support portion 35a and guides the sliding of the main valve body 31. By this direct acting bearing 38, there is no or reduced motion friction and static friction between the main valve body 31 and the housing 5 (specifically, the valve body support portion 35a of the support body 35 fixed to the housing 5). In the aspect, the main valve body 31 is supported by the housing 5. As the linear motion bearing 38, for example, a rolling bearing such as a ball bearing or a roller bearing as shown in FIG. 2 can be used. Here, the direct acting bearing 38 is attached to the inner periphery of the opening 31c of the main valve body 31, and a ball or a roller included in the direct acting bearing 38 rolls on the surface of the valve body supporting portion 35a.

  A spring 63 is disposed between the main valve body 31 and the first spring seat 35b of the support body 35 that are separated in the opening / closing direction. Specifically, the spring 63 is interposed between the second spring seat 62 b of the backing member 62 disposed on the rear end side of the main valve body 31 and the first spring seat 35 b of the support body 35. . The spring 63 is a biasing member that biases the main valve body 31 in the closing direction. In the present embodiment, a compression coil spring is used as the spring 63, but a spring of another form such as a disc spring or an elastic body may be used as the spring 63.

  An elastic film 34 (diaphragm) and an inner pressing member 61 are provided between the main valve body 31 and the backing member 62. In the present embodiment, the backing member 62 and the inner pressing member 61 are separate bodies, but they may be configured integrally. An outer pressing member 64 is provided on the outer side of the inner pressing member 61.

  The elastic membrane 34 is a member that seals between the rear end of the main valve body 31 and the wall of the main valve chamber 53. The elastic film 34 isolates the first area 58 and the second area 59 of the main valve chamber 53. The elastic film 34 is an elastically deformable flexible metal, resin, or rubber thin film, and has an annular shape. The elastic membrane 34 is a second region between the inner peripheral edge portion connected to the rear end of the main valve body 31, the outer peripheral edge portion connected to the wall of the main valve chamber 53, and the inner peripheral edge portion and the outer peripheral edge portion. It integrally has an elastically deforming portion bent toward the 59 side.

  The inner peripheral edge of the elastic membrane 34 is sandwiched between the main valve body 31 and the inner pressing member 61 from both sides in the opening / closing direction. The inner pressing member 61 is biased by the spring 63 in the opening / closing direction closing direction. In this manner, the inner peripheral edge of the elastic film 34 is pressed and held between the main valve body 31 and the inner pressing member 61. On the other hand, the outer peripheral edge of the elastic membrane 34 is sandwiched from both sides in the opening and closing direction by a step surface 53 a provided on the wall of the main valve chamber 53 and the outer pressing member 64. The outer pressing member 64 is pressed in the closing direction by the support body 35 and the lid 81. In this way, the outer peripheral edge of the elastic film 34 is pressed and held between the step surface 53a and the outer pressing member 64. Note that the inner diameter of the main valve chamber 53 is increased at the joint with the elastic membrane 34, and a step surface 53a is formed here.

  The backing member 62 is formed with a backing portion 62a that comes into contact with the elastic deformation portion (the portion bent toward the second region 59) of the elastic film 34. The backing member 62 has an annular shape, a second spring seat 62b and a pressing surface 62c are formed on the inner peripheral side, and a backing portion 62a and a second stopper surface 62d are formed on the outer peripheral side. Is formed. The radial cross section of the backing portion 62a has a curved shape that protrudes toward the second region 59 so as to follow the bending shape of the elastically deforming portion of the elastic film 34.

  The outer pressing member 64 has a cylindrical shape extending in the opening / closing direction between the surface of the support 35 where the first spring seat 35 b is provided and the step surface 53 a of the wall of the main valve chamber 53. A first stopper surface 64 b is formed on the inner peripheral side of the outer pressing member 64. The first stopper surface 64b and the second stopper surface 62d of the backing member 62 are opposed to each other in the opening / closing direction by the rated displacement amount of the main valve body 31. Further, when the first stopper surface 64b of the outer pressing member 64 and the second stopper surface 62d of the backing member 62 abut, further movement of the main valve body 31 in the opening direction is restricted (FIG. 3, reference). The outer pressing member 64 is provided with a flow path 64a that communicates the inside and outside of the cylinder. A first pilot channel 54 is opened in the wall of the main valve chamber 53 in the vicinity of the opening on the outer peripheral side of the channel 64a. In the present embodiment, the outer pressing member 64 and the support 35 are separate bodies, but the outer pressing member 64 and the support 35 may be integrally configured.

  In the main valve 3 configured as described above, the first region 58 of the main valve chamber 53 includes an outer periphery of the main valve body 31, an inner periphery of the main valve chamber 53, and a space defined by the elastic film 34. Further, in the second region 59 of the main valve chamber 53, a space on the inner peripheral side of the main valve body 31, a space on the inner peripheral side of the outer pressing member 64, and a valve body support portion 35a of the support body 35 communicating these. The communication flow path 35c formed in is included. The first region 58 and the second region 59 are communicated with each other by a flow channel 31b communicating between the inside and the outside of the main valve body 31, and a throttle 32 is provided in the flow channel 31b.

  Next, the pilot valve 4 will be described. The pilot valve 4 includes a pilot valve body 41 (plunger) inserted into the pilot valve chamber 56 so as to be movable in the opening / closing direction. The pilot valve body 41 has a pilot valve portion 41 a at one end in the opening and closing direction (hereinafter referred to as “tip”). The pilot valve portion 41 a can be seated on a pilot valve seat portion 46 provided between the second pilot flow path 55 and the pilot valve chamber 56. The pilot valve body 41 has a direction in which the pilot valve portion 41a approaches the pilot valve seat portion 46 (hereinafter referred to as “closed direction”) and a direction in which the pilot valve portion 41a moves away from the pilot valve seat portion 46 (hereinafter referred to as “open direction”). And can be moved.

  The pilot valve 4 further includes a spring 42 that is a biasing member that biases the pilot valve body 41 in the closing direction, and a drive unit 43 that moves the pilot valve body 41 in the opening direction against the biasing force of the spring 42. I have. The drive unit 43 includes an iron core (not shown) provided at least at the rear end of the pilot valve body 41, a solenoid coil 45 provided so as to cover the rear end of the pilot valve body 41 from the outside, and a solenoid coil. And current supply means (not shown) for supplying a drive current to 45. The spring 42 is provided between the cap 44 attached to the housing 5 and the pilot valve body 41 so as to cover the solenoid coil 45.

  In the pilot valve 4 configured as described above, when a drive current is supplied to the solenoid coil 45, the pilot valve body 41 moves in the opening direction, the pilot valve 4 is opened, and the supply of drive current to the solenoid coil 45 is cut off. The pilot valve body 41 is moved in the closing direction by the bias of the spring 42, and the pilot valve 4 is closed.

  Here, the operation of the valve device 1 configured as described above will be described. The pressure of the fluid in the first region 58 of the primary side flow passage 51 and the main valve chamber 53 communicating with the primary side flow passage 51 is set to the primary pressure P1, the first pilot flow passage 54 and the first pressure of the main valve chamber 53 communicating therewith. The fluid pressure in the second region 59 is referred to as the operating pressure P3, and the fluid pressure in the secondary side flow path 52 and the second pilot flow path 55 communicating therewith is referred to as the secondary side pressure P2.

  As shown in FIGS. 1 and 2, when the pilot valve 4 is closed and the main valve 3 is closed, the pressure of the fluid in the valve device 1 is balanced. At this time, since no fluid flows in the main flow path 50, the primary pressure P1 and the operation pressure P3 are equal (P1 = P3), and the main valve 3 is closed by the biasing force of the spring 63. Further, the secondary side pressure P2 when the main valve 3 is closed is sufficiently smaller than the primary side pressure P1, and is sufficiently small so that the influence on the driving of the main valve body 31 can be ignored.

  When the pilot valve 4 is opened by energizing the drive unit 43, the fluid flows from the pilot channel 60 to the secondary channel 52. As a result, fluid flows from the first region 58 to the second region 59 of the main valve chamber 53, and the primary side pressure P1 and the operating pressure P3 are caused by the throttle 32 provided between the first region 58 and the second region 59. A differential pressure ΔP is generated. When this differential pressure ΔP becomes larger than the minimum operating differential pressure ΔPmin, as shown in FIG. 3, the main valve body 31 overcomes the biasing force of the spring 63 and moves in the opening direction, and the main valve 3 is opened. Thus, when the pilot valve 4 is opened, the relationship of “primary side pressure P1> operation pressure P3> secondary side pressure P2” is established, and the fluid flows down through the main flow path 50.

  When the pilot valve 4 is closed again, the differential pressure ΔP between the primary pressure P1 and the operating pressure P3 decreases to become smaller than the minimum operating differential pressure ΔPmin, and the main valve body 31 is closed by the biasing force of the spring 63. The main valve 3 is closed.

  As described above, when the main valve 3 is opened and closed, the main valve element 31 moves in the opening and closing directions, and the movement of the main valve element 31 is guided by the direct acting bearing 38. Therefore, the main valve body 31 has a floating seal structure that does not directly contact the main valve chamber 53, and the main valve body 31 can move in the opening / closing direction without being eccentric. Since the main valve body 31 and the wall of the main valve chamber 53 are not in direct contact with each other, there is no kinetic friction and static friction between them, and there is a sliding resistance between the main valve body 31 and the main valve chamber 53 when moving. Does not occur. Further, the kinetic friction and static friction between the main valve body 31 and the valve body support portion 35a for guiding and supporting the main valve body 31 are substantially zero or sufficiently smaller than the case where there is no direct acting bearing 38, and the main valve body is small. The sliding resistance with respect to the valve body support portion 35a during the movement of 31 is substantially zero or sufficiently small as compared with the case where the direct acting bearing 38 is not provided.

  When the main valve body 31 moves in the opening direction, the elastic film 34 is elastically deformed following the movement of the main valve body 31, and the inner peripheral edge of the elastic film 34 moves in the opening direction (see FIG. 3). At this time, the elastic deformation portion of the elastic film 34 is deformed while being in contact with the backing portion 62 a formed on the backing member 62, thereby preventing the elastic membrane 34 from being damaged. In this way, the pressure resistance and durability of the elastic film 34 are improved.

  As described above, the kinetic friction and static friction between the main valve body 31 and the housing 5 are substantially zero or sufficiently small as compared with the case without the direct acting bearing 38, and the housing 5 is moved when the main valve body 31 moves. Is substantially zero or sufficiently smaller than the case where there is no linear motion bearing 38. In addition, since the elastic film 34 follows the movement of the main valve body 31, the movement of the main valve body 31 is not hindered. Therefore, since the resistance force acting on the main valve body 31 when the main valve body 31 moves is substantially zero or sufficiently smaller than that of the conventional valve, the responsiveness of the valve opening operation and the valve closing operation of the main valve 3 is improved. To do.

  Furthermore, the sliding resistance force between the main valve body 31 and the housing 5 does not have to be taken into consideration for the minimum operating differential pressure ΔPmin required for the valve opening operation of the main valve 3. Therefore, the minimum operating differential pressure ΔPmin only needs to be a value that can overcome the urging force of the spring 63, and can be set to a smaller value than in the conventional case. Thus, the minimum operating differential pressure ΔPmin is reduced, so that the responsiveness of the valve opening operation and the valve closing operation of the main valve 3 can be improved. Moreover, the pressure loss of the main valve body 31 can be reduced by reducing the minimum operating differential pressure ΔPmin. Further, since there is no deterioration of the seal member for sealing between the main valve chamber 53 and the main valve body 31 as in the prior art, the substantial minimum operating differential pressure ΔPmin does not change, and the stable main valve 3 The opening / closing operation is continued.

  Further, in the opening / closing operation of the main valve 3, the main valve body 31 and the main valve chamber 53 are not in direct contact, and the main valve body 31 slides relative to the valve body support portion 35a of the support body 35. The wear of the sliding portion between the main valve body 31 and the housing 5 (that is, the direct acting bearing 38 and the valve body support portion 35a) is extremely small. Therefore, since it is not necessary to replace the deteriorated seal member as in the conventional case, the durability of the main valve 3 can be improved.

  The preferred embodiment of the present invention has been described above, but the above configuration can be modified as follows, for example. In the following description of the modification of the present embodiment, the same or similar members as those of the above-described embodiment are denoted by the same reference numerals in the drawings, and the description thereof is omitted.

(Modification 1)
In the main valve 3 of the above embodiment, the sliding portion (the direct acting bearing 38) between the main valve body 31 and the housing 5 is provided with a lubricant such as grease and a mechanism for preventing the lubricant from flowing out downstream. May be. For example, in the main valve 3 according to the modified example 1-1 shown in FIG. 4, a direct acting bearing 38 is provided between the opening 31 c of the main valve body 31 and the valve body support 35 a of the support 35. A pair of packings 71 and 71 (sealing members) are provided so as to sandwich the direct acting bearing 38 from both sides in the opening and closing direction. In FIG. 4, 72 is a packing presser. A space between the pair of packings 71 and 71 is filled with a lubricant such as grease.

  For example, in the main valve 3 according to the modified example 1-2 shown in FIG. 5, the direct acting type is provided between the outer periphery of the main valve body 31 and the valve body support portion 53 d provided on the wall of the main valve chamber 53. A bearing 38 is provided, a space on one side in the opening / closing direction of the linear motion type bearing 38 is sealed with an elastic film 34, and a space on the other side in the opening / closing direction is sealed with a packing 71. The space between the elastic film 34 and the packing 71 is filled with a lubricant such as grease.

  In the main valve 3 according to the modified examples 1-1 and 1-2, the direct acting bearing 38 is lubricated by the lubricant, and the movement of the direct acting bearing 38 becomes smoother. The drag acting on the main valve body 31 can be further reduced. Further, the lubrication of the direct acting bearing 38 can improve the durability of the direct acting bearing 38 and, consequently, the durability of the valve device 1. In addition, in order not to generate sliding resistance when the main valve body 31 is moved due to the friction force generated between the main valve body 31 or the valve body support portion 35a and the packing 71, the binding force of the packing 71 is a leakage of the lubricant. It is desirable to employ a very small one that can prevent the above.

(Modification 2)
In the valve device 1 according to the above embodiment, the primary fluid is supplied to the main valve 3 from one place (primary channel 51). However, the primary side fluid may be supplied to the main valve 3 from two places.

  For example, in the valve device 1 according to the second modification shown in FIG. 6, the second primary flow path 57 is provided in the lid 81 that encloses the main valve 3 in the main valve chamber 53. The second primary channel 57 is connected to the second region 59 of the main valve 3 by a channel 35 g formed in the support 35. A throttle 32 is provided in the flow path 35g. Thus, since the flow path 35g and the throttle 32 for flowing the primary side fluid to the first pilot flow path 54 are formed in the support body 35, the flow path and the throttle of the main valve body 31 as in the above embodiment. Is unnecessary. Since it is not necessary to machine a hole in the main valve body 31, the degree of freedom in selecting the material of the main valve body 31 is increased. For example, the entire main valve body 31 can be made of resin.

  In the valve device 1 according to the second modified example, the pressure of the fluid in the primary side flow path 51 and the first region 58 of the main valve 3 communicating with the primary side flow path 51 and the second primary side flow path 57 is the primary pressure. P1. In this valve device 1, when the pilot valve 4 is opened, a fluid flow from the second primary-side flow path 57 to the second region 59 of the main valve 3 is generated, and the restriction 32 provided therebetween causes the flow of fluid. A differential pressure ΔP is generated between the primary pressure P1 and the operating pressure P3. When this differential pressure ΔP becomes larger than the minimum operating differential pressure ΔPmin, the main valve body 31 overcomes the biasing force of the spring 63 and moves in the opening direction, and the main valve 3 is opened.

(Modification 3)
In the embodiment described above, the direct acting bearing 38 of the main valve 3 includes the shaft-shaped valve body support portion 35a provided on the support body 35, and the opening of the main valve body 31 into which the valve body support portion 35a is inserted. 31c. However, since the main valve body 31 only needs to be supported by the housing 5 so as to be movable in the opening and closing direction, the support form of the main valve body 31 by the housing 5 is not limited to the embodiment.

  For example, in the main valve 3 according to the modified example 3-1 shown in FIG. 7, a valve body support portion 53 d is provided on the wall of the main valve chamber 53. A direct acting bearing 38 for sliding the main valve body 31 in the opening / closing direction with respect to the main valve chamber 53 is provided between the inner periphery of the valve body support portion 53 d and the outer periphery of the main valve body 31. That is, the main valve body 31 is supported by the housing 5 from the outer peripheral side via the direct acting bearing 38. In the main valve 3 according to the first modification, the movement of the main valve body 31 is guided to the main valve chamber 53, so that the support body 35 does not require the valve body support portion 35 a. In the main valve 3 according to the modified example 3-1, the direct acting bearing 38 is attached to the main valve chamber 53, and the main valve body 31 is reduced in weight. By reducing the weight of the main valve body 31, the load of the inertial force of the main valve body 31 with respect to the differential pressure is reduced. Therefore, the responsiveness of the valve opening / closing operation of the main valve 3 can be improved.

  Further, for example, in the main valve 3 according to the modified example 3-2 shown in FIG. 8, the main valve body 31 is provided with a shaft-shaped portion 31d extending in the opening direction. The shaft-shaped portion 31d protrudes toward the support 35 from the elastic film 34. On the other hand, the support 35 is provided with an opening in the closing direction as the valve support 35e. And the shaft-shaped part 31d of the main valve body 31 is inserted in the valve-body support part 35e of the support body 35, and it is a direct acting type between the inner periphery of the valve-body support part 35e, and the outer periphery of the shaft-shaped part 31d. A bearing 38 is arranged. The direct acting bearing 38 is attached to the inner periphery of the valve body support portion 35 e of the support body 35.

  The support 35 is provided with a flow path 35f that communicates the inside of the valve support 35e and the outer peripheral side. A first pilot channel 54 is opened in the wall of the main valve chamber 53 in the vicinity of the opening on the outer peripheral side of the channel 35f. Thus, the first pilot flow path 54 and the inside of the valve body support portion 35e of the support body 35 are communicated with each other by the flow path 35f. Further, the support 35 is formed with a flow path 35g communicating with the second primary flow path 57 (see FIG. 6) formed in the lid 81, and the throttle 32 is provided in the flow path 35g. ing. In the main valve 3 according to the modified example 3-2, in order to further reduce the weight of the main valve body 31, the main valve body 31 is made of resin, and is the same as the main valve 3 according to the above-described modified example 2. In addition, the support 35 is provided with a flow path and a throttle for supplying the primary side fluid to the second region 59.

  In the main valve 3 according to the modified example 3-2, the inside of the valve body support portion 35e of the support body 35, the flow path 35f of the support body 35, the outer periphery of the support body 35, and the inner periphery of the main valve chamber 53. A second region 59 is constituted by the space between them. The second region 59 is communicated with the second primary channel 57 through the channel 35 f of the support 35.

  Further, in the main valve 3 according to the modified example 3-2, the outer pressing member 64 is provided such that one end in the opening / closing direction is in contact with the elastic film 34 and the other end in the opening / closing direction is also in contact with the support body 35. It has been. However, like the main valve 3 according to the modified example 3-3 shown in FIG. 9, the outer pressing member 64 does not come into contact with the support 35 and does not have a pressing force from the support 35. May be. In this case, the outer pressing member 64 is press-fitted between the inner periphery of the main valve chamber 53 and the outer periphery of the backing member 62. A space between the outer pressing member 64 and the support 35 that is separated in the opening / closing direction is used as a part of the second region 59.

(Modification 4)
In the above embodiment, the direct acting bearing 38 provided between the main valve body 31 of the main valve 3 and the housing 5 is a rolling bearing such as a ball bearing (ball bearing) or a roller bearing. However, the direct acting bearing 38 is not limited to a rolling bearing, and may be a sliding bearing. In the case where the linear motion bearing 38 is a sliding bearing, the configuration is simpler than that of a rolling bearing, so that the cost and weight can be reduced.

  For example, in the main valve 3 according to the modified example 4-1 shown in FIG. 10, a bush 74 as a sliding bearing is fitted on the inner periphery of the valve body support portion 35e of the support body 35. The inner peripheral surface of the bush 74 is a sliding surface of the sliding bearing. At least the sliding surface of the bush 74 is made of a material that has been subjected to surface treatment (for example, lubrication, lubrication, etc.) to reduce friction with the shaft-shaped portion 31d of the main valve body 31 or that reduces friction. It is configured. The shaft-shaped portion 31 d of the main valve body 31 is inserted into the inner periphery of the bush 74. In the above configuration, when the main valve body 31 moves in the opening / closing direction when the valve is opened / closed, the shaft-shaped portion 31d of the main valve body 31 slides on the inner peripheral surface (sliding surface) of the bush 74.

  Further, for example, in the main valve 3 according to the modification 4-2 shown in FIG. 11, the inner peripheral surface of the valve body support portion 35e of the support body 35 is a sliding surface, and the valve body support portion 35e itself is It functions as a sliding bearing. For this reason, the internal peripheral surface of the valve body support part 35e of the support body 35 is formed in the smooth surface without an unevenness | corrugation. Further, a pair of packing receivers 76 that are separated from each other in the opening / closing direction are formed on the inner peripheral surface of the valve body support portion 35e of the support body 35, and packings 77 are disposed therein. Between the pair of packings 77 and between the outer periphery of the shaft-shaped portion 31d of the main valve body 31 and the inner periphery of the valve body support portion 35e of the support body 35, a lubricant such as grease is filled. . With this lubricant, the outer peripheral surface of the shaft-shaped portion 31d and the inner peripheral surface of the valve body support portion 35e are lubricated, and the friction between the shaft-shaped portion 31d and the valve body support portion 35e is reduced. In the above configuration, when the main valve body 31 moves in the opening and closing direction when the valve is opened and closed, the shaft-shaped portion 31d of the main valve body 31 slides on the inner peripheral surface (sliding surface) of the valve body support portion 35e of the support body 35. To do.

DESCRIPTION OF SYMBOLS 1 Pilot type valve apparatus 3 Main valve 4 Pilot valve 5 Housing 31 Main valve body 31a Main valve part 31b Flow path 31c Opening part 32 Restriction 34 Diaphragm (elastic film)
35 support body 35a valve body support section 35b first spring seat 35e valve body support section 41 pilot valve body 50 main flow path 51 primary side flow path 52 secondary side flow path 53 main valve chamber 54 first pilot flow path 55 second Pilot flow path 56 Pilot valve chamber 60 Pilot flow path 61 Inner pressing member 62 Backing member 62a Backing portion 62b Second spring seat 63 Spring 64 Outer pressing member

Claims (12)

A main flow path composed of a primary flow path and a secondary flow path, a main valve chamber formed between the primary flow path and the secondary flow path, the secondary flow path and the A pilot channel connecting the main valve chamber, and a housing having a pilot valve chamber formed in the pilot channel;
A pilot valve body disposed in the pilot valve chamber to open and close the pilot flow path;
The main valve chamber is disposed in the main valve chamber so as to partition the first valve chamber into a first region communicating with the primary flow path and a second region communicating with the pilot flow path, and the first region and the first A main valve body that opens and closes the main flow path in accordance with a differential pressure of fluid with respect to the two regions;
A valve body support provided in the housing and supporting the main valve body in a non-contacting manner with a wall of the main valve chamber and being movable in an opening and closing direction;
An urging member for urging the main valve body in an opening / closing direction closing direction;
An elastic membrane provided between the housing and the main valve body and separating the first region and the second region;
A pilot-type valve device comprising:   The pilot type valve device according to claim 1, further comprising a direct acting bearing provided between the main valve body and the valve body support portion.   The elastic membrane has an annular shape, and includes an inner peripheral edge portion connected to the main valve body, an outer peripheral edge portion connected to a wall of the main valve chamber, and the inner peripheral edge portion and the outer peripheral edge portion. The pilot type valve device according to claim 1, further comprising an elastically deforming portion that is bent toward the second region.   The pilot-type valve apparatus as described in any one of Claims 1-3 further provided with the backing member which contacts the said 2nd area | region side of the said elastic film, and moves with the said main valve body.   5. The pilot valve device according to claim 4, wherein the backing member has a ring shape, and a radial cross section of a portion in contact with the elastic film has a curved shape that protrudes toward the second region. .   The pilot type valve device according to claim 4 or 5, wherein a seat for holding the biasing member is formed integrally with the backing member. A pair of sealing members disposed so as to sandwich the linear motion bearing from the opening and closing direction;
The pilot type valve device according to any one of claims 2 to 6, further comprising a lubricant filled between the pair of sealing members. The main valve body has a shaft-shaped portion extending in the opening and closing direction,
The pilot valve device according to any one of claims 1 to 7, wherein the valve body support portion has an opening into which the shaft-shaped portion of the main valve body is inserted. The valve body support portion has an axial shape portion extending in the opening and closing direction,
The pilot valve device according to any one of claims 1 to 7, wherein the main valve body has an opening into which the shaft-shaped portion of the valve body support portion is inserted.   The pilot type valve device according to any one of claims 2 to 7, wherein the valve body support portion is provided on an inner periphery of the main valve chamber.   The pilot type valve device according to any one of claims 2 to 10, wherein the direct acting bearing is a rolling bearing.   The pilot type valve device according to any one of claims 2 to 10, wherein the direct acting bearing is a sliding bearing.

Images