WO2006112236A1

WO2006112236A1 - Flow rate control valve

Info

Publication number: WO2006112236A1
Application number: PCT/JP2006/306141
Authority: WO
Inventors: Kazutoshi Itoh; Masashi Yanagawa
Original assignee: Ckd Corporation
Priority date: 2005-04-14
Filing date: 2006-03-27
Publication date: 2006-10-26
Also published as: JP2006292137A; KR20070114317A; CN101160486A

Abstract

A flow rate control valve where flow path resistance is reduced to facilitate a flow of fluid, that cab stabilize the flow of the fluid, where valve opening can be varied at high-speed to an accurate degree of valve opening, where response of valve opening and closing can be improved, and whose life can be extended. In the flow rate control valve, a flow path entry port (16), a valve body (21), a linear conversion mechanism, and a flow path exit port (17) are arranged on a straight line. The linear conversion mechanism has a ball screw nut (27) for transmitting rotational drive of a servomotor (31), a ball screw (23) for converting the rotational drive into linear drive, and a ball screw main shaft (26) where splines for transmitting the linear drive are formed. The valve body (21) parallelly moves in the direction of the center axis of the flow path entry port (16) and the flow path exit port (17) and is integral with the ball screw main shaft (26).

Description

Specification

Flow control valve

Technical field

The present invention relates to a flow control valve that controls, for example, a vacuum pressure.

Background art

[0002] As a background art, the following flow control valve exists as an invention of Patent Document 1. FIG. 4 is a cross-sectional view of the flow path opening / closing valve 101 of the invention of Patent Document 1, and shows the valve closed state. The flow path opening / closing valve 101 has an outer shape formed by valve nosing 111. The valve housing 111 has flange portions 112, 113 at both ends, and a fluid flow path is provided between the flange portions 112, 113. 114 is formed. When the drive shaft 115 is rotated in the L direction as shown in FIG. 4, the valve element 117 is lifted away from the valve seat 118 by the tensile force of the panel 116. Further, when the drive shaft 115 is rotated in the L direction, the valve body 117 pivots about the connection point A, and the valve body disk portion 119 substantially overlaps the pipe portion centerline shaft 120 as shown in FIG. The valve opening degree of the flow path opening / closing valve 101 becomes the maximum.

FIG. 6 shows a cross-sectional view of the flow control valve 201 of the invention of Patent Document 2. This non-reflow body 201 is connected to the non-reflex body 211, and the non-reb body 211 is connected to the flow passage port 212, the valve seat 213 hole 214, the valve chamber 215, and the flow passage port 212 to form a flow passage 216. ing. In addition, a stepping motor 221 is disposed in the drive system, and the rotational driving force of the stepping motor 221 is converted into a linear driving force by the eccentric cam 222, and the valve body 217 is controlled via the valve body operating member 223. Thus, valve opening and valve closing operations are performed.

[0004] Furthermore, in the conventional air cylinder type direct acting valve, a driving force is applied to the valve body by the air cylinder in order to perform valve opening and valve closing operations.

Patent Document 1: JP-A-10-196806

Patent Document 2: JP 2002-168361

Disclosure of the invention

Problems to be solved by the invention However, in the flow path opening / closing valve 101 of Patent Document 1, the opening / closing operation of the valve is performed by rotating the first link 121, the second link 122, and the third link 123. And the valve opening cannot be set accurately. In addition, the force of the fluid flowing along the fluid flow path 114 formed between the flange portions 112 and 113, and the rotation of the disc disc portion 119 is performed against the flow of the fluid. This may cause the fluid flow to become unstable.

[0006] In addition, in the flow control valve 201 of Patent Document 2 and the air cylinder type direct acting valve in which the conventional force exists, the flow path between the flow path port 212 and the flow path port 218 is formed in a right angle. . For this reason, a portion where the fluid stays is likely to be generated, and the flow path resistance becomes high and the fluid is difficult to flow.

Furthermore, in the flow rate control valve 201 of Patent Document 2, the rotational driving force of the stepping motor 221 is converted into a linear driving force by the eccentric cam 222. However, since the eccentric cam 222 is likely to slip during conversion of the driving force, it takes a lot of time to perform accurate positioning, and it is difficult to accurately vary the valve opening at high speed. In addition, the mounting part of the stepping motor 221 becomes large and the flow control valve becomes large.

[0008] And, in an air cylinder type direct acting valve in which a conventional force exists, a driving force is applied to the valve body by the air cylinder in order to perform valve opening and valve closing operations. As a result, the responsiveness of the valve opening and closing operations is lower than when driven by a motor. In addition, since the seal member of the cylinder piston part operates while being in constant contact, the service life is shortened.

[0009] Here, consider a vacuum control valve connected to a vacuum chamber used in a semiconductor production line or the like. In a vacuum control valve connected to a vacuum chamber used in a semiconductor production line or the like, it is desired that no fluid stays in the vacuum control valve in order to ensure a vacuum in the vacuum chamber. . In addition, in order to accurately control the pressure in the chamber directly connected to the flow path inlet port with high responsiveness, it is desired that the valve opening of the vacuum control valve be accurately varied at high speed. Furthermore, due to the frequent frequency of valve opening and closing operations, it is desired to increase the durability of the vacuum control valve and extend its life. [0010] Therefore, the present invention can reduce the flow path resistance to facilitate the flow of the fluid, can stabilize the flow of the fluid, can be changed to a fast and accurate valve opening, An object of the present invention is to provide a flow control valve that can increase the responsiveness of the opening and closing operations and can prolong the service life.

Means for solving the problem

In order to achieve the above object, the present invention has the following features.

(1) In the flow control valve in which the first port, the valve body, the linear structure, and the second port are arranged on a straight line, the present invention converts the nut that transmits the rotational drive of the servo motor and the rotational drive to linear drive. A linear transformation comprising a ball screw that rotates and a main shaft on which a spline that transmits linear driving is formed, and a valve body that is translated in the direction of the central axis of the first port and the second port and that is integral with the main shaft. It is characterized by having.

[0012] (2) The present invention provides the flow rate control valve according to (1), wherein a support member disposed on the inner peripheral surface side of the substantially cylindrical cover portion, and a substantially cylindrical bracket attached to the support member And a ball screw disposed on the inner peripheral surface side of the bracket, a main shaft disposed on the inner peripheral surface side of the ball screw, and a valve body disposed on the end of the main shaft opposite to the ball screw. It is characterized by having.

[0013] (3) The present invention is the flow control valve according to (1) or (2), wherein the servo motor disposed on the outer peripheral surface side of the substantially cylindrical cover portion is integrated with the servo motor. Timing to connect the first pulley arranged on the second port side, the second pulley arranged on the second port side, which is integrated with the ball screw nut constituting the ball screw, and the first pulley and the second pulley It is characterized by having a belt.

[0014] (4) In the present invention, in any one of the flow control valves described in (1) to (3), when the valve open state force is also set to the valve closed state, the valve body is moved to the valve seat by the driving force of the motor. The servo motor is stopped when the torque value of the servo motor reaches a predetermined value.

The invention's effect

[0015] The present invention having such characteristics has the following effects.

(1) In the present invention, the first port, the valve body, the linear deformation, and the second port are arranged on a straight line. In the flow control valve, a linear structure comprising a nut for transmitting the rotational drive of the servo motor, a ball screw for converting the rotational drive to a linear drive, and a main shaft on which a spline for transmitting the linear drive is formed, and a first port and a second The parallel movement in the direction of the center axis of the 2 ports has a valve body integrated with the main shaft, so the flow path is formed in a straight line! Therefore, the flow resistance is reduced and the fluid flows. The valve body moves parallel to the fluid flow, and the fluid flow can be stabilized, and the servo motor is driven by the built-in encoder signal.

Is accurately transmitted to the valve body, so the valve opening can be changed at high speed and accurately, and the servo motor can be driven at high speed to increase the responsiveness of the valve opening and closing operations. Since the drive of the motor is transmitted to the valve body by the main shaft on which the ball screw and the spline are formed, an effect that the durability of the drive mechanism portion is high and the life can be extended is obtained.

(2) The present invention provides the flow rate control valve according to (1), wherein a support member disposed on the inner peripheral surface side of the substantially cylindrical cover portion, and a substantially cylindrical bracket attached to the support member And a ball screw disposed on the inner peripheral surface side of the bracket, a main shaft disposed on the inner peripheral surface side of the ball screw, and a valve body disposed on the end of the main shaft opposite to the ball screw. Therefore, in addition to the effect described in (1), the flow of fluid can be stabilized because each component is arranged in parallel to the fluid flow direction.

[0017] (3) The present invention provides the flow rate control valve described in (1) or (2), wherein the servo motor disposed on the outer peripheral surface side of the substantially cylindrical cover portion is integrated with the servo motor. Timing to connect the first pulley arranged on the second port side, the second pulley arranged on the second port side, which is integrated with the ball screw nut constituting the ball screw, and the first pulley and the second pulley In addition to the effects described in (1) or (2), the fluid control valve can be miniaturized by making the mounting of the servo motor compact.

[0018] (4) The present invention relates to any one of the flow rate control valves described in (1) to (3), wherein when the valve is opened, the valve body is moved to the valve seat by the driving force of the servo motor. Since the servo motor is stopped when the torque value of the servo motor reaches a predetermined value, the load described in (1) to (3) is added to the seal member. Therefore, it is possible to increase the life of the valve mechanism. Brief Description of Drawings

FIG. 1 is a cross-sectional view (valve closed state) of a vacuum pressure control valve 1 of the present invention.

FIG. 2 is a cross-sectional view (valve open state) of the vacuum pressure control valve 1 of the present invention.

FIG. 3 is a cross-sectional view taken along line AA in FIG.

FIG. 4 is a cross-sectional view (valve closed state) of the flow path opening / closing valve of Patent Document 1.

FIG. 5 is a cross-sectional view (valve open state) of the flow path opening / closing valve of Patent Document 1.

FIG. 6 is a cross-sectional view of a flow control valve of Patent Document 2.

FIG. 7 is an external view of a center flange in the vacuum pressure control valve 1 of the present invention.

Explanation of symbols

1 Vacuum pressure control valve

11 Flange body

12 Inline body

13 Motor flange

21 Disc

22 Bellows

23 Bonore screw

24 Honoreda

26 Bonore screw spindle

27 Ball screw nut

31 Servo motor

32 Timing belt

33 Large pulley

34 Small pulley

35 ENCODER BEST MODE FOR CARRYING OUT THE INVENTION

[0021] Examples of the present invention will be described below. In this embodiment, a vacuum pressure control valve will be described among the fluid control valves. FIG. 1 is a cross-sectional view of a vacuum pressure control valve 1 of the present invention, showing a valve closed state. As shown in Figure 1, the vacuum pressure control valve 1 has a flange body 11 The outer shape is formed by the in-line body 12 and the motor flange 13 as a substantially cylindrical cover portion. A flow path 14 is formed on the inner peripheral side of the inline body 12. A flow path 13a is also formed on the inner peripheral side of the motor flange 13 as shown in FIG. Here, FIG. 3 is a cross-sectional view taken along line AA shown in FIG.

[0022] The internal configuration of the vacuum pressure control valve 1 can be broadly divided into a valve mechanism section and a drive mechanism section. As shown in Fig. 1, the valve mechanism consists of a flow path inlet port 16, a flow path outlet port 17, a valve body 21, a bellows 22, a ball screw 23, a holder 24, a ball screw spindle 26, a ball screw nut 27, a seal Forces such as member 28 and valve seat 29 are also constructed. The ball screw 23 is disposed on the inner peripheral side of a holder 24 that is a substantially cylindrical bracket, and the holder 24 is coupled by a bolt at a bolt hole 36a of a center flange 36 that is a support member. A flow path 36b is formed in the center flange 36 as shown in FIG. 7, and is sandwiched and held between the in-line body 12 and the motor flange 13. A ball screw main shaft 26 is disposed on the inner peripheral surface side of the ball screw 23. The bellows 22 integrated with the valve body 21 and the holder 24 is arranged so as to cover the outer periphery of the ball screw main shaft 26. The bellows 22 can freely expand and contract in the direction of the axis 15 and insulates the flow path 14 and the ball screw 23, so that outside air does not enter the flow path 14 even when vacuumed. A valve body 21 is coupled to the end of the ball screw main shaft 26 opposite to the ball screw 23. A large pulley 33 described later is coupled to a ball screw nut 27 disposed on the flow path outlet port 17 side of the ball screw 23. Further, a seal member 28 is disposed at the end of the valve body 21. In this manner, each component is disposed between the flow path inlet port 16 and the flow path outlet port 17 in parallel to the fluid flow direction.

On the other hand, as shown in FIG. 1, the drive mechanism section includes a servo motor 31, a timing belt 32, a large pulley 33, a small pulley 34, and the like. The servo motor 31 is disposed on the outer peripheral surface side of the inline body 12 and the motor flange 13. A small pulley 34 is coupled to the flow path outlet port 17 side of the servo motor 31.As described above, the large pulley 33 is disposed on the ball screw nut 27 disposed on the flow path outlet port 17 side of the ball screw 23. Are combined. The large pulley 33 and the small pulley 34 are connected by a timing belt 32. The timing belt outlet 25 where the timing belt 32 is disposed is isolated from the flow path 14 by a motor flange 13 having a cross section as shown in FIG. The servo built in the servo motor 31 The position of the valve disc 21 can be grasped by calculating the signal of the reader 35.

The vacuum pressure control valve 1 having such a configuration operates as follows. When the valve closing state force in Fig. 1 is also set to the valve opening state, the servo motor 31 is first rotated. Then, the ball screw nut 27 connected by the timing belt 32 is rotated, and the ball screw main shaft 26 is translated in the direction of the axis 15 toward the drive mechanism. Then, the valve body 21 integrated with the ball screw main shaft 26 is separated from the valve seat 29. At this time, the opening area of the flow path inlet port 16 can be adjusted by changing the distance between the valve body 21 and the valve seat 29. As a result, the flow rate and pressure of the fluid can be changed and adjusted, and as a result, the pressure in a chamber (not shown) directly connected to the flow path inlet port 16 is controlled.

[0025] On the other hand, when the valve open state force is also set to the valve closed state, the servo motor 31 is rotated in the opposite direction to the above case. Then, the ball screw nut 27 connected by the timing belt 32 rotates in the opposite direction to the above case, so that the ball screw main shaft 26 moves in the direction of the axis 15 and moves in the opposite direction to the above case. Then, the valve body 21 is pressed against the valve seat 29, and the servo motor 31 is stopped when the torque value of the servo motor 31 reaches a predetermined value. At this time, by using a motor with a brake as the servo motor 31, the torque value by the servo motor 31 can be maintained at a predetermined value. Even when a motor without a brake is used, by outputting an arbitrary torque value from the servo motor 31, the torque value by the servo motor 31 can be maintained at a predetermined value. The predetermined value of the torque value by the servo motor 31 here is arbitrarily set and corresponds to the degree of vacuum in the flow path inlet port 16 and the flow path 14, and the seal member 28 and the valve. It is a value that can achieve the required sealing force with the seat 29.

As described above, in the vacuum pressure control valve 1 of the present invention, the ball screw main shaft 26 in which a spline is formed via the ball screw 23 by rotating the ball screw nut 27 using the servo motor 31 as a drive source. By driving, the valve is opened and closed. Therefore, the responsiveness of the valve opening and valve closing operations can be enhanced by the high-speed driving of the servo motor 31. Further, since the moving amount of the valve body 21 can be accurately adjusted by the encoder 35 incorporated in the servo motor 31, the valve opening can be set accurately. Therefore, the pressure in the chamber (not shown) directly connected to the flow path inlet port 16 can be accurately controlled with high responsiveness. . Furthermore, the drive torque can be minimized by using the ball screw 23 or the ball screw main shaft 26 with splines formed as the drive transmission mechanism of the servo motor 31, so extra load is applied to the valve mechanism. The durability can be increased without applying force S. In addition, since the servo motor 31 is disposed on the outer peripheral surface side of the in-line body 12 and the motor flange 13, the flow control valve can be downsized.

In addition, as shown in FIG. 1 and FIG. 2, since the flow path inlet port 16 and the flow path outlet port 17 are on the same axis, the fluid staying portion is reduced and the flow resistance is reduced. Makes it easier to flow. In addition, the valve body 21 is located on the same axis between the flow path inlet port 16 and the flow path outlet port 17.

Since it moves back and forth, it moves along the direction of fluid flow. For this reason, the fluid flow is not hindered and the fluid staying portion is not generated, so that the fluid easily flows. Furthermore, each component of the valve mechanism is disposed between the flow path inlet port 16 and the flow path outlet port 17 in parallel with the fluid flow direction. Therefore, when the valve is opened, the fluid flows into the flow path inlet port 16. Then, it passes through the outer peripheral side of the valve body 21 and smoothly flows to the channel outlet port 17 via the channel 14, the channel 36b of the center flange 36, and the channel 13a of the motor flange 13. For this reason, the fluid stays in the vacuum pressure control valve 1 and the fluid easily flows. Since the fluid easily flows in this way, the relationship between the valve opening and the flow rate is stabilized, and the pressure in the chamber (not shown) directly connected to the flow path inlet port 16 can be accurately controlled. It can also be evacuated.

Furthermore, in the vacuum pressure control valve 1 of the present invention, the valve body 21 is driven using only the servo motor 31 as a drive source. Therefore, the sealing force applied from the valve body 21 to the sealing member 28 when the valve is closed is only the driving force of the servo motor 31. Therefore, since the sealing force more than necessary is not applied to the seal member 28, there is no possibility that the seal member 28 is permanently deformed even when the valve is closed for a long time. Therefore, the durability of the vacuum pressure control valve 1 can be improved.

[0029] The following effects can be obtained by the embodiment described above.

(1) The present invention transmits the rotational drive of the servo motor 31 in a vacuum pressure control valve in which the flow path inlet port 16, the valve body 21, the linear deformation, and the flow path outlet port 17 are arranged in a straight line. A ball screw nut 27 that converts the rotational drive into a linear drive, and a ball screw main shaft 26 on which a spline for transmitting the linear drive is formed, and a flow inlet port 16 and a flow outlet port. Since it has a ball screw main shaft 26 and an integral valve element 21, the flow path is formed in a straight line, so that the flow of the fluid is reduced by reducing the flow resistance. Since the valve body 21 moves parallel to the fluid flow, the fluid flow can be stabilized, and the drive of the servo motor 31 is accurately driven by the signal of the built-in encoder 35. 21, the valve opening can be changed to an accurate valve opening speed, and the responsiveness of the valve opening and closing operations can be enhanced by the high speed driving of the servo motor 31. The drive is transmitted to the valve body 21 by the ball screw main shaft 26 formed with the ball screw 23 and the spline, so that the durability of the drive mechanism is increased and the life can be extended.

[0030] (2) The present invention relates to the vacuum pressure control valve described in (1), a center flange 36 disposed on the inner peripheral surface side of the substantially cylindrical inline body 12 and the motor flange 13, and a center flange. A substantially cylindrical holder 24 attached to the screw 36, a ball screw 23 disposed on the inner peripheral surface side of the holder 24, a main shaft 26 disposed on the inner peripheral surface side of the ball screw 23, and a ball screw 23 And the valve body 21 disposed at the end of the opposite main shaft 26, the effect described in (1) is neglected and each component is disposed in parallel with the fluid flow. The flow can be stabilized.

[0031] (3) The present invention relates to a servo motor 31 arranged on the outer peripheral surface side of the substantially cylindrical inline body 12 and motor flange 13 in the vacuum pressure control valve described in (1) or (2). The small pulley 34 that is integrated with the servo motor 31 and disposed on the flow path outlet port 17 side, and the ball screw nut 27 that constitutes the ball screw 23, and is disposed on the flow path outlet port 17 side. Since it has the large pulley 33 and the timing belt 32 that connects the small pulley 34 and the large pulley 33, the installation of the servo motor 31 is made compact in consideration of the effect described in (1) or (2). By doing so, the fluid control valve can be reduced in size.

(4) In the vacuum pressure control valve described in (1) to (3), the present invention is configured so that the valve element 21 is moved to the valve seat 29 by the driving force of the servomotor 31 when the valve is opened to the valve closed state. Hold on Therefore, since the servo motor 31 is stopped when the torque value of the servo motor 31 reaches a predetermined value, the load described in (1) is not applied and an unnecessary load is not applied to the seal member 28. The effect which can lengthen the lifetime of a mechanism part is acquired.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. In this embodiment, the vacuum pressure control valve has been described, but the present invention can also be applied to a chemical liquid control valve, an air pressure control valve, and the like. In this embodiment, a servo motor is used, but a stepping motor may be used. Furthermore, in this embodiment

I used a timing belt, but I used a gear train.

Claims

The scope of the claims

[1] In the flow control valve in which the first port, valve body, linear conversion mechanism, and second port are arranged in a straight line,

A linear shelf structure comprising a nut for transmitting the rotational drive of a servo motor, a ball screw for converting the rotational drive into a linear drive, and a main shaft on which a spline for transmitting the linear drive is formed;

A valve body that is translated in the direction of the central axis of the first port and the second port and is integral with the main shaft;

A flow control valve characterized by comprising:

[2] In the flow control valve according to claim 1,

A support member disposed on the inner peripheral surface side of the substantially cylindrical cover portion, a substantially cylindrical bracket attached to the support member, and the ball screw disposed on the inner peripheral surface side of the bracket; A flow rate control valve comprising: the main shaft disposed on the inner peripheral surface side of the ball screw; and a valve body disposed on an end portion of the main shaft opposite to the ball screw.

[3] In the flow control valve according to claim 1 or claim 2,

A servo motor disposed on the outer peripheral surface side of the substantially cylindrical cover portion, a first pulley integral with the servo motor and disposed on the second port side, and a ball screw nut constituting the ball screw; A flow rate control valve comprising: a second pulley that is integral and disposed on the second port side; and a timing belt that connects the first pulley and the second pulley.

[4] In any one of the flow control valves according to claims 1 to 3,

Valve opening force When the valve is closed, the valve body is pressed against the valve seat by the driving force of the motor, and the servo motor is stopped when the torque value of the servo motor reaches a predetermined value. Flow control valve.