JPH0573373U - Valve device - Google Patents

Abstract

(57) [Abstract] [Purpose] When the shaft 39 and the valve plug are assembled using the split ring 60 and the ring retainer 61, the split ring 60 does not fall out from the fitting groove 63 of the shaft 39 even when the shaft 39 is horizontal. The purpose is to improve the assembly workability. [Structure] The shaft 39 is provided with a fitting groove 63 into which a split ring 60 is fitted. The split ring 6 projecting from the fitting groove 63 on the inner peripheral surface of the one end opening of the ring retainer 61 fitted on the shaft 39 and screwed into the valve plug.
An annular groove 71A in which the outer peripheral portion of 0 is fitted is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a so-called in-line type valve device in which a valve shaft actuator is incorporated in a valve body.

[0002]

[Prior Art]

 Conventionally, this type of valve device was designed to reduce the size of the device by reducing the number of components that were placed outside the valve by incorporating the valve shaft actuator itself or part of it into the valve body. JP-A-63-47579 and JP-A-63-45476 are known. Among them, the former valve device uses an electric motor as an actuator, and its rotating magnetic field generating coil is arranged on the outer circumference of the pipe body, and in response to this, the rotor is arranged inside the pipe body or the whole electric motor. Is incorporated into the pipe body, and the rotation of the rotor is converted into the linear movement of the valve plug with a screw to control the opening and closing of the valve. On the other hand, the latter valve device transmits the rotation of a power source provided outside the pipe body to a flexible shaft whose one end is inserted into the pipe body, and the rotation of the flexible shaft is transmitted to the valve shaft by a pair of bevel gears. And the rotation of the valve shaft is converted into a linear movement of the valve plug by a screw. Since the conventional valve devices having such a configuration use screws, the valve plug can be operated strongly, the valve shutoff performance can be improved, and the flow rate characteristic part of the valve plug can be improved. It has the advantage that the flow characteristics can be freely determined by the shape.

[0003]

[Problems to be solved by the device]

However, in such a conventional valve device, since the valve plug receives an unbalanced force (thrust) due to the pressure difference between the primary side and the secondary side of the controlled fluid, a driving force large by this thrust is required. There was a problem to say. That is, when the primary pressure of the controlled fluid is P ₁ , the secondary pressure is P ₂ , and the pressure receiving area of the valve plug is S, the thrust P received by the valve plug is (P ₁ −P ₂ ) × S. .. For example, when the valve plug is arranged on the primary side, it is necessary to overcome this thrust P during opening operation to operate the valve plug. On the contrary, when it is arranged on the secondary side, it operates against the thrust P during closing operation. I need to let you know. Therefore, it is difficult to apply it to high-pressure fluid, and if it is used from low pressure to high pressure, the drive part becomes large, and the advantage of downsizing the in-line type is impaired. Also, in this type of valve device, in order to improve the shut-off characteristic at the time of closing and to absorb the shock at the time of closing the valve, the valve plug is attached while allowing a slight movement with respect to the shaft, and by a spring. Biasing is performed in the valve closing direction. In that case, a split ring and ring retainer should be used as the structure for mounting the valve plug on the shaft, and the split ring should determine the initial tightening position of the spring. With a structure that fits in the groove and the annular groove of the valve plug and the split ring is pressed by the ring retainer, the split ring easily falls off the shaft due to the gap between the fitting groove and the lead frame ring during assembly. In addition, the valve plug must be inserted vertically and the valve shaft must be inserted in order to prevent it from falling off, so the assembly direction is restricted and the assembly workability is extremely poor.

Therefore, the present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to prevent the split ring from falling off at the time of assembly and to make the valve plug horizontal. The split ring can be assembled without falling off, the degree of freedom in the direction of assembly can be increased, and the valve device has good assembly workability.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a valve body, an electric motor that is coaxially arranged on the valve body, such as a stator and a rotor, and one opening of the valve body that is connected to a shaft provided on the rotor. In a valve device equipped with a valve plug that controls opening and closing, a split ring is fitted into the fitting groove provided on the shaft with a part of the outer periphery protruding from the fitting groove, and the ring retainer is fitted to the shaft. At the same time, it is screwed into the valve plug, and the ring retainer is provided with an annular groove into which the outer peripheral portion protruding from the fitting groove of the split ring fits.

[0006]

[Action]

 In the present invention, the split ring is fitted in the fitting groove of the shaft, and then the ring retainer is fitted on the shaft to cover the outer periphery of the split ring with the annular groove of the retainer ring. This prevents the split ring from falling out of the fitting groove. Then, the shaft is inserted into the valve plug, and the ring retainer is screwed into the valve plug while covering the split ring to integrally connect the shaft and the valve plug.

[0007]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. FIG. 1 is a sectional view showing an embodiment of the valve device according to the present invention, and FIG. 2 is a disassembled perspective view of some components. In these drawings, the present embodiment shows an example in which the valve plug is applied to a single-seat type valve device in which the valve plug is arranged at the secondary side opening of the valve device. The valve device, generally designated by reference numeral 1, includes a valve body 2 connected in the middle of piping. The valve main body 2 is composed of an inlet side valve main body 2A and an outlet side valve main body 2B which are formed in a substantially symmetrically divided shape and are coaxially opposed to each other, and a flange portion 3 of the inlet side valve main body 2A has an upstream side pipe. 4 is fastened and fixed to the flange portion of No. 4 by a plurality of bolts and nuts (not shown), and the flange portion 5 of the outlet side valve body 2B is fastened and fixed to the flange portion of the downstream side pipe 6 by the same bolts and nuts. . Further, the secondary side opening 7 of the outlet side valve body 2B is formed smaller than the primary side opening 8 so that the seat ring 9 is press-fitted and fixed from the downstream side opening end.

Between the inlet side valve body 2A and the outlet side valve body 2B, a pulse motor 11 as an electric motor that constitutes an actuator of the valve plug 10 is arranged via an O-ring 12, and these three components are connected to each other. The person is integrally connected by a plurality of bolts 13. The pulse motor 11 itself is well known in the art, and is composed of a stator 14 and a rotor 15. The stator 14 is provided in parallel with the outer cylindrical body 16, a pair of left and right ring plates 18A and 18B fitted and fixed to the openings at both ends of the outer cylindrical body 16 via O-rings 17, and in the circumferential direction of the inner surface of the outer cylindrical body 16. A large number of cores 19, a coil 20 wound around the core 19, and both ends are welded and fixed to the inner peripheral surfaces of the ring plates 18A and 18B to protect the core 19 and the coil 20 from the controlled fluid 21. The cylinder 22 is made of a non-magnetic material. The rotor 15 includes a cylindrical rotor body 23 located at the center of the inside of the valve device 1, and a plurality of magnetic bodies 24 arranged in parallel on the outer peripheral surface of the rotor body 23 so as to correspond to the core 19. The upstream end of 23 is formed to have a small diameter, and is rotatably fitted through a bearing 27 in a bearing hole 26 formed in the center of the inner surface of the shaft guide 25. The shaft guide 25 has a plurality of fluid passage holes 28 formed in a disk shape and arranged at equal intervals in the circumferential direction, and a plurality of outer peripheral portions are formed on the outer surface of the upstream ring plate 18A. It is fixed by a screw 29. A sliding shaft portion 30 is slidably provided at the center of the outer surface of the shaft guide 25 so as to slidably guide and hold an upstream end portion of a shaft 39, which will be described later.

Reference numeral 31 is a plug guide (guide member) that slidably guides and holds the valve plug 10 in the axial direction. The plug guide 31 has a bottomed cylindrical shape with an upstream end surface closed and a downstream end surface open. When the valve plug 10 is inserted, the cylindrical portion 31A and the bottom plate 31B are integrally formed, and the outer peripheral portion of the flange portion 31C provided at the central portion of the outer peripheral surface of the cylindrical portion 31A is located on the downstream side. It is fixed to the outer surface of the ring plate 18B by a plurality of screws 33. A plurality of fluid passage holes 34 are formed in the collar portion 33C at appropriate intervals in the circumferential direction. The closed end of the plug guide 31 is rotatably fitted through a bearing 36 to a recess 35 formed in the downstream end surface of the rotor main body 23, so that the rotor main body 23 has a closed end. While forming a downstream bearing, the opening end is coaxially opposed to the seat ring 9 with an appropriate gap. The bottom plate 31B has a shaft insertion hole 38 in the center, and a shaft 39 for advancing and retracting the valve plug 10 is inserted through the shaft insertion hole 38 through an O ring 40.

A male screw portion 41 is formed at an upstream end portion of the shaft 39 projecting from the shaft insertion hole 38 to the upstream side of the valve guide 31, and the male screw portion 41 is formed in the rotor body 23. The male screw portion 41 is screwed into a screw hole 46 formed at the center and communicating with the recessed portion 35, and the tip 39a of the male screw portion 41 slides into a through hole 47 formed in the sliding shaft portion 30 of the shaft guide 25. It is freely inserted and is prevented from rotating by the key 49. Therefore, when the rotor 15 is rotated by driving the pulse motor 11, the shaft 39 moves back and forth. In this case, the rotor 15 rotates forward and backward by changing the phase of the electric current applied to the coil 20, moves the shaft 39 forward when it rotates in the forward direction, and moves it backward when it rotates in the reverse direction. Incidentally, 50 is a key groove, and 51 is a retaining ring of the shaft 39.

The valve plug 10 has a communication passage 54 formed in a cylindrical shape and penetratingly formed in the center of the valve plug 10. A downstream end surface facing the seat ring 9 forms a characteristic portion 57, and an outer peripheral portion of the valve plug 10 has a valve portion. A seating surface 57A is formed by abutting against the inner open end surface of the seat ring 9 when closed. The valve plug 10 is slidably fitted to the plug guide 31 via a seal member 58, and a slight axial movement is allowed at the downstream end of the shaft 39 inserted into the plug guide 31. Are linked together.

This connecting structure is composed of a split ring 60 and a ring retainer 61. As shown in FIG. 2, the split ring 60 is composed of a pair of semicircular ring pieces 60A and 60B that are formed in two parts. The split ring 60 has an outer peripheral portion in a fitting groove 63 formed on the outer peripheral surface of the shaft 39. It is projected and fitted. The ring retainer 61 includes a main body 61A formed of a cylindrical body with both ends open and having a male screw 68 formed on the outer peripheral surface thereof, and a flange portion 61B integrally provided on the outer peripheral surface of the upstream opening end of the main body 61A. , Is slidably fitted on the shaft 39. The ring retainer 61 is connected to the valve plug 10 by screwing the main body 61A into a screw hole formed in the inner surface of the valve plug 10 in communication with the communication passage 54 as shown in FIG. The flange portion 61B is in close contact with the inner surface of the valve plug 10. The downstream opening end of the central hole 70 through which the shaft 39 of the main body 61A penetrates and the upstream opening end of the communication passage 54 of the valve plug 10 project from the fitting groove 63 of the split ring 60. The annular groove 71 (71A, 71B) into which the outer peripheral portion is fitted is continuously formed, and the groove width is set to be larger than the width of the split ring 60. Therefore, an appropriate gap 73 is provided between the split ring 61 and the annular groove 71, and the axial movement of the valve plug 10 and the ring retainer 61 is allowed within this gap 73. . After the seating surface 57A of the valve plug 10 comes into contact with the seating portion of the seat ring 9, that is, the inner opening end surface during the closing operation, the gap 73 is moved forward by a predetermined amount, and the shaft 39 is moved forward by a predetermined amount. By further compressing a compression coil spring 76 (which will be described later) that constitutes the cushioning mechanism of FIG.

When mounting the valve plug 10 and the shaft 39, first, the ring retainer 61 is fitted to the shaft 39, the split ring 60 is fitted to the fitting groove 63, and then the ring retainer 61 is fitted to the split ring. Cover with 60. Then, the outer peripheral portion of the split ring 60 protruding from the fitting groove 63 fits into the annular groove 71A of the ring retainer 61. Therefore, the split ring 60 is held at the inner and outer peripheral portions by the fitting groove 63 and the annular groove 71A, so that the split ring 60 does not fall off even when the shaft 39 is directed downward. After the compression coil spring 76 is inserted into the communication passage 54 of the valve plug 10, the shaft 39 is inserted into the communication passage 54 of the valve plug 10 and the ring retainer 61 is screwed into the screw hole of the valve plug 10. At this time, the shaft 39 is moved toward the ring retainer 61 by the spring 76. In this way, the ring retainer 61 is fully screwed in to form the aforementioned gap 73 between the inner wall of the annular groove 71B of the valve plug 10 and the split ring 60.

A small-diameter portion 75 is integrally formed on the downstream end surface of the shaft 39. The small-diameter portion 75 has the compression coil spring 76 for urging the valve plug 10 and the ring retainer 61 to the downstream side. Is fitted, the one end of which is pressed against the downstream end surface of the shaft 39, and the other end of which is pressed against a step portion 78 provided in the communication passage 54 of the valve plug 10. The small diameter portion 75 stably holds the compression coil spring 76, and prevents the abnormal deformation of the compression coil spring 76 that occurs when the spring is used in the vicinity of the contact height without providing the small diameter portion 75. It has a function of minimizing the entry and exit of the communication passage 21 into the communication passage 54 and preventing the corrosion of the compression coil spring 76. That is, when the controlled fluid 21 is a corrosive fluid and enters and leaves the space in which the compression coil spring 76 is housed, corrosion of the compression coil spring 76 progresses and shortens its life. Is provided so that the tip portion is inserted into the small diameter portion of the communication passage 54 on the opening end side, that is, the passage portion on the downstream side of the stepped portion 78, so that the fluid intrusion into the spring chamber can be minimized. This is advantageous when the compression coil spring 76 is less corroded and therefore the spring must be made of an inexpensive material with low corrosion resistance.

An inner chamber 80 is formed between the bottom plate 31 B of the plug guide 31 and the ring retainer 61. The inner chamber 80 is a passage 81 formed in the downstream end of the shaft 39. Further, it is communicated with the secondary side opening 7 of the outlet side valve body 2B through the communication passage 54. Therefore, the pressure in the inner chamber 80 is equal to the secondary pressure P ₂ . The passage 81 is formed at the center of the shaft 39, one end of which is opened to the tip end surface of the small diameter portion 75, and the other end of which is bent in the radial direction of the shaft 39 and opened to the outer peripheral surface of the shaft 39 so that the inner chamber 80 Is in communication with.

In the valve device 1 having such a configuration, the valve plug 10 is pressed against the seating portion of the seat ring 9 by the spring force of the compression coil spring 76 when fully closed. In this state, when the pulse motor 11 is driven to rotate the rotor 15 in the reverse direction, the shaft 39 moves backward while rotating by the amount corresponding to the gap 73, and thereafter the valve plug 10 also moves backward together with this. Then, the seat ring 9 is opened, and the upstream opening 8 and the downstream opening 7 of the downstream valve body 2B are made to communicate with each other. Therefore, the controlled fluid 21 flows into the downstream pipe 6 through the gap between the seat ring 9 and the valve plug 10.

Here, in the present invention, the valve plug 10 is slidably fitted in the valve guide 31, and the inner chamber 80 of the valve guide 31 is sealed by the O-ring 40 and the seal member 58. 10 is isolated from the primary pressure P ₁ and communicated with the downstream opening 7 of the valve device 1 by the communication passage 54 and the passage 81, so that the pressure in the inner chamber 80 is made substantially equal to the secondary pressure P _2. Therefore, the thrust force P due to the pressure difference (P ₁ −P ₂ ) between the primary side and the secondary side of the controlled fluid 21 causes the inner diameter of the seat ring 9 and the outer diameter of the guide of the valve plug 10 to coincide with each other. It is the product of the cross-sectional area S ₁ and the differential pressure (P ₁ −P ₂ ) at the O-ring 40 portion of the shaft 39, regardless of the cross-sectional area of ₁₀ . Therefore, the thrust P is smaller than that of the conventional device, and the driving force of the valve device 1 can be reduced. Further, if the thrust P becomes small, it can be used for high-pressure fluid.

Further, in the present invention, the ring retainer 61 is provided with the annular groove 71A, and when the valve plug 10 and the shaft 39 are assembled, the split ring 60 is fitted into the fitting groove 71A of the shaft 39 to split the ring retainer 61. Since the ring 60 is covered, the shaft 39 is fitted into the valve plug 10 while keeping this state, and the ring retainer 61 is screwed into the valve plug 10. Does not fall off from the fitting groove 63, and the workability of assembly can be improved.

[0019]

[Effect of the device]

 As described above, according to the valve device of the present invention, the ring retainer is provided with the annular groove, and the annular groove covers the outer peripheral portion of the split ring. Therefore, when the shaft and the valve plug are assembled, Even if the shaft is horizontal, it is possible to reliably prevent the split ring from coming off the fitting groove of the shaft, and it is possible to improve the assembly workability.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a valve device according to the present invention.

FIG. 2 is an exploded perspective view of some components.

[Explanation of symbols]

 1 Valve device 2 Valve body 3, 5 Flange 9 Seat ring 10 Valve plug 11 Pulse motor 14 Stator 15 Rotor 31 Plug guide 31B Bottom plate 38 Shaft insertion hole 39 Shaft 40 O-ring 54 Communication passage 57 Characteristic portion 57A Seating surface 60 Split ring 61 Ring retainer 63 Fitting groove 71A Annular groove 80 Inner chamber 90 Hollow protrusion 91 Valve throttle

Claims (1)

[Scope of utility model registration request] 1. A valve body, an electric motor comprising a stator, a rotor and the like coaxially arranged on the valve body, and a valve plug connected to a shaft provided on the rotor to open and close one opening of the valve body. In the valve device including, a split ring is fitted into the fitting groove provided in the shaft by partially protruding the outer periphery from the fitting groove, and a ring retainer is fitted to the shaft and screwed into the valve plug,
A valve device, wherein an annular groove into which an outer peripheral portion of the split ring protruding from the fitting groove is fitted is provided in the ring retainer.