WO2012023342A1

WO2012023342A1 - Fluid control device

Info

Publication number: WO2012023342A1
Application number: PCT/JP2011/064309
Authority: WO
Inventors: 立視鍋井; 雪恵中村
Original assignee: シーケーディ株式会社
Priority date: 2010-08-20
Filing date: 2011-06-22
Publication date: 2012-02-23
Also published as: KR101250654B1; CN103097789A; JPWO2012023342A1; US20130142675A1; KR20130021404A; TW201211431A; TWI427230B; JP5150009B2

Abstract

A fluid control device configured in such a manner that a valve element is not strongly pressed against the valve seat, etc. and that an excessive load is not applied to a motor. A flow rate adjustment device is provided with: a first engagement section (90) provided to the drive shaft (111) of a motor; and a second engagement section (80) movable in the axial direction relative to the first engagement section (90) and transmitting and receiving a rotational force to and from the first engagement section (90). The flow rate adjustment device is provided with: a valve element (41) for adjusting the extent of opening of a flow path (21); and a rod (60) which is connected to the valve element (41), is movable in the axial direction, and is prevented from rotating about the axis. The flow rate adjustment device is provided with: a male thread section (82) and a female thread section (64) which mesh with each other and which are fed relative to each other by the threads in the axial direction when rotated relative to each other: a protrusion section (51) for preventing the second engagement section (80) from moving further toward the valve seat (24) side than a first restriction position; and a first cylinder (30) for preventing the rod (60) from moving further toward the valve seat (24) side than a second restriction position.

Description

Fluid control device

The present invention relates to a fluid control device that controls the position of a valve element based on rotation of a motor.

Conventionally, as a fluid control device of this type, by rotating a male screw member connected to a drive shaft of a motor, a female screw member that meshes with the male screw member is screwed in the axial direction of the male screw member, and the valve body in the open state is Some determine the position (see, for example, Patent Documents 1 and 2). In those described in Patent Documents 1 and 2, the stop position of the valve body in the open state is determined by the piston connected to the valve body striking the female screw member.

Japanese Patent Laid-Open No. 2003-083466 JP 2007-278514 A

By the way, in the thing of patent document 1, 2, when a female screw member is screwed in the axial direction of a male screw member and the opening degree of the valve body in an open state is made small, a female screw member contacts a piston or another member. There is a fear. In that case, there is a possibility that an excessive load is applied to the motor due to the valve body being strongly pressed against the valve seat or the like, or screw feed of the female screw member being restricted.

The present invention has been made in view of such circumstances, and it is a main object of the fluid control device to suppress the valve body from being strongly pressed against a valve seat or the like and an excessive load applied to the motor. Is.

The present invention employs the following means in order to solve the above problems.

The first means moves relative to the first engagement portion along the axial direction of the drive shaft, a motor having a drive shaft, a first engagement portion provided on the drive shaft. A second engagement portion that receives a rotational force from the first engagement portion, a valve body provided with a fluid flow path and a valve seat part, and an opening of the flow path provided opposite to the valve seat part. A valve body that adjusts the degree of movement, a moving member that is connected to the valve body, is allowed to move in the axial direction, and is restricted from rotating around the axis, and a direction in which the valve body approaches the valve seat portion An elastic member for applying a force to the moving member, a first restricting portion for restricting the second engaging portion from moving to the valve seat portion side from the first restricting position, and the moving member being a second member. A second restricting portion for restricting movement to the valve seat portion side from the restricting position, and the second engaging portion and the front Moving member, by being screwed to each other, and wherein the relatively moving along the said moving member and the second engaging portion in the axial direction by relative rotation.

According to the above configuration, when the motor is driven, the first engagement portion provided on the drive shaft of the motor is rotated. Then, the rotational force is transmitted from the first engagement portion to the second engagement portion, and the second engagement portion is rotated. Further, the valve body is provided with a fluid flow path and a valve seat portion, and a valve body for adjusting the opening degree of the flow path is provided opposite to the valve seat portion. A moving member is connected to the valve body, the moving member is movable in the axial direction of the drive shaft, and rotation about the axis is restricted.

A male screw part and a female screw part are provided on one and the other of the second engaging part and the moving member, respectively. The male screw portion and the female screw portion mesh with each other, and are relatively screw-fed in the axial direction of the drive shaft by relative rotation. Then, when the second engaging portion is rotated, the moving member whose rotation is restricted and the second engaging portion are relatively rotated.

At this time, the movement of the second engagement portion toward the valve seat portion from the first restriction position is restricted by the first restriction portion. For this reason, the moving member moves away from the valve seat portion by rotating the drive shaft in the direction in which the second engaging portion and the moving member approach, that is, the direction in which the second engaging portion is pressed against the first restricting portion. Screwed. A force in a direction in which the valve body approaches the valve seat is applied to the moving member by an elastic member. For this reason, when the moving member is screwed, the moving member is moved against the force of the elastic member. And according to the screw feed amount of a moving member, the distance of a valve seat part and a valve body, ie, the opening degree of a flow path, is adjusted.

On the other hand, when the drive shaft is rotated in a direction in which the second engaging portion and the moving member are separated from each other, the moving member is screw-fed in a direction approaching the valve seat portion. At this time, since the force in the direction in which the valve body is brought close to the valve seat portion is applied to the moving member by the elastic member, the second engaging portion is connected to the first restricting portion via the male screw portion and the female screw portion that mesh with each other. It is pressed against. When the moving member reaches the second restricting position, the second restricting portion restricts the moving member from moving toward the valve seat portion.

Here, the first engaging portion and the second engaging portion are relatively movable in the axial direction of the drive shaft. For this reason, when the movement of the moving member is restricted, the second engaging portion is rotated so that the second engaging portion is separated from the moving member, that is, the second engaging portion is the first restricting portion. Screwed in the direction away from Therefore, even if the motor is further driven from the state where the movement of the moving member is restricted, it is possible to suppress the valve body from being strongly pressed against the valve seat portion and an excessive load applied to the motor. As a result, generation of particles from the valve body and the valve seat, deformation and damage of the valve body and the valve seat, damage to the motor, and the like can be suppressed.

Furthermore, the first engaging portion and the second engaging portion transmit a rotational force to each other, while the first engaging portion and the second engaging portion are relatively movable in the axial direction of the drive shaft. For this reason, the reaction of the force that screw-feeds the moving member in the axial direction and the reaction of the force that screw-feeds the second engagement portion away from the first restricting portion act in the axial direction with respect to the drive shaft of the motor. This can be suppressed. As a result, an increase in the rotational load of the motor can be suppressed, and the durability of the motor can be reduced and the increase in size of the motor can be suppressed.

In the second means, in the first invention, the second restricting portion is provided with a spacer for adjusting the second restricting position, and movement of the moving member is restricted by the second restricting portion. In the state, a gap is provided between the valve seat portion and the valve body.

According to the above configuration, the second restricting position is adjusted by the spacer in the second restricting portion that restricts the moving member from moving toward the valve seat portion relative to the second restricting position. For this reason, it is possible to precisely control the distance between the valve seat portion and the valve body, that is, the fluid flow state, in a state where the valve body is closest to the valve seat portion. Furthermore, since the gap is provided between the valve seat portion and the valve body in a state where the movement of the moving member is restricted by the second restricting portion, it is possible to avoid the valve body from hitting the valve seat portion. As a result, generation of particles from the valve body and the valve seat can be effectively suppressed. In particular, it is effective to apply the above configuration to a flow rate adjustment device or a pressure adjustment device that is used in a state in which the valve body maintains the opening of the flow path at a constant level.

According to a third means, in the second invention, a cylinder for guiding the movement of the moving member in the axial direction is provided, and the cylinder is provided with an insertion port through which the spacer can be inserted from the outside. It is characterized by that.

According to the above configuration, the movement of the moving member in the axial direction is guided by the cylinder. A spacer can be inserted from the outside of the cylinder through the insertion port. For this reason, after assembling the fluid control device, the distance between the valve seat portion and the valve body can be precisely adjusted by the spacer. Therefore, it is not necessary to require high dimensional accuracy for the valve body, cylinder, moving member, etc., and it is possible to maintain fluid control accuracy while suppressing costs.

According to a fourth means, in any one of the first to third inventions, one of the first engagement portion and the second engagement portion includes a rectangular parallelepiped insertion portion, and the other includes the insertion portion. A concave portion that can be inserted in the axial direction is provided, and the outer side surface of the insertion portion that is parallel to the inner side surface of the concave portion is fitted with a gap.

According to the above configuration, in the axial direction of the drive shaft, the rectangular parallelepiped insertion portion provided in one of the first engagement portion and the second engagement portion can be inserted into the recess provided in the other. The outer side surfaces of the insertion portion that are parallel to each other and the inner side surface of the recess are fitted with a gap. Therefore, the first engagement portion and the second engagement portion can be moved relative to each other in the axial direction of the drive shaft, and the first engagement portion and the second engagement portion can mutually rotate. Can communicate. Therefore, a 1st engaging part and a 2nd engaging part are realizable by simple structure.

Furthermore, it is possible to manually adjust the position of the valve body by exposing the second engaging portion and manually rotating the second engaging portion. For this reason, the maintainability of the fluid control apparatus can be improved.

As in the fifth means, in the first to fourth inventions, if the motor is a stepping motor that rotates in synchronization with the pulse power, an excessive load is applied to the motor. By suppressing the stepping, it is possible to suppress the stepping motor from stepping out. Therefore, it is possible to suppress a decrease in position adjustment accuracy due to step-out while employing a stepping motor having excellent position adjustment accuracy and controllability.

The fragmentary sectional view which shows a flow volume adjustment apparatus. The elements on larger scale of FIG. The figure which shows an insertion port and a shim. The disassembled perspective view which shows a 1st engaging part and a 2nd engaging part. The elements on larger scale which show the opening operation | movement of the valve body in a flow regulating device. The elements on larger scale which show the closing operation of the valve body in a flow regulating device.

Hereinafter, an embodiment will be described with reference to the drawings. In this embodiment, it is embodied as a flow rate adjusting device that adjusts the flow rate of liquid in a semiconductor manufacturing apparatus or the like.

FIG. 1 is a partial cross-sectional view showing the flow rate adjusting device 10.

The flow rate adjusting device 10 (fluid control device) includes a valve body 20, a first cylinder 30, a second cylinder 50, a motor 110, and a housing 120.

The valve body 20 is provided with an inflow port 25 through which a fluid (liquid) flows and an outflow port 26 through which the liquid flows out. The valve body 20 is made of a chemical-resistant fluororesin such as PTFE (Poly-Tetra-Fluoro-Ethylene). Inside the valve body 20, a flow path 21 connected to the inflow port 25, a flow path 23 connected to the outflow port 26, and a valve chamber 22 connecting these

flow paths

21 and 23 are provided. . The valve chamber 22 is formed as a cylindrical space, and opens on one surface (upper surface) of the valve body 20. Then, a liquid having a predetermined pressure flows from the inflow port 25.

The first cylinder 30 is fixed to one surface (upper surface) of the valve body 20 where the valve chamber 22 opens. The first cylinder 30 is formed of a general-purpose resin such as PP (Poly Propylene). A columnar first accommodating portion 31 is formed inside the first cylinder 30. The first accommodating portion 31 passes through the first cylinder 30, and the central axis of the valve chamber 22 coincides with the central axis of the first cylinder 30. The first accommodating portion 31 communicates with the valve chamber 22.

The second cylinder 50 is fixed to one surface (upper surface) of the first cylinder 30 opposite to the valve body 20. The second cylinder 50 is made of a general-purpose resin such as PP (PolyPoPropylene). Inside the second cylinder 50, a cylindrical second accommodating portion 54 and a cylindrical third accommodating portion 55 are formed. The second storage part 54 and the third storage part 55 are in communication with each other, and their central axes coincide with the central axis of the first storage part 31. The second accommodating portion 54 opens on one surface (lower surface) of the second cylinder 50, and the third accommodating portion 55 opens on one surface (upper surface) opposite to the second cylinder 50. The second housing part 54 communicates with the first housing part 31 of the first cylinder 30. The diameter of the second storage part 54 is made larger than the diameter of the first storage part 31. For this reason, a step is formed between the first housing part 31 and the second housing part 54.

Between the second housing part 54 and the third housing part 55, an annular projecting part 51 is provided by the inner walls projecting inward. That is, the overhanging portion 51 is a boundary between the second housing portion 54 and the third housing portion 55.

In the second cylinder 50, a stepping motor 110 (motor) is fixed to one surface (upper surface) of the third accommodating portion 55 that is open through an attachment portion 113. The motor 110 includes a drive circuit 112, and a signal line 132 from a controller (not shown) is connected to the drive circuit 112. Then, a drive control signal (pulse signal) is input from the controller to the drive circuit 112, and the rotational position of the drive shaft 111 of the motor 110 is controlled by a drive control signal corresponding to the number of steps. A photosensor 74 is provided on the outer periphery of the second cylinder 50, and a signal line 131 from the controller is connected to the photosensor 74. A housing 120 is fixed to one surface (upper surface) of the first cylinder 30 opposite to the valve body 20. The housing 120 covers the second cylinder 50, the motor 110, and the photosensor 74.

FIG. 2 is a partially enlarged view of FIG.

As shown in the figure, a columnar rod 60 is accommodated across the first accommodation part 31 and the second accommodation part 54. The rod 60 is formed of a fluorine resin having chemical resistance, such as PVDF (Poly Vinylidene Di Fluoride). In the rod 60, the valve body 20
A cylindrical valve body 41 is connected to the end on the side. A diaphragm 42 is provided on the outer peripheral edge of the valve body 41. An annular support 43 is provided on the outer peripheral edge of the diaphragm 42. The support portion 43 is fixed between the valve body 20 and the first cylinder 30. The diaphragm 42 divides the valve chamber 22 and the first storage portion 31, and the liquid in the valve chamber 22 is prevented from flowing into the first storage portion 31.

The valve body 41 includes an enlarged diameter portion 41a having a larger diameter than other portions. In the valve body 20, an annular valve seat portion 24 is provided at a connection portion between the flow path 21 and the valve chamber 22. And the enlarged diameter part 41a of the valve body 41 is arrange | positioned so that the valve seat part 24 may be opposed. The wall surface of the valve seat part 24 and the wall surface of the enlarged diameter part 41a are parallel, and the distance between these wall surfaces is uniform.

The rod 60 (moving member) includes a first rod part 61 accommodated in the first accommodating part 31 and a second rod part 62 accommodated in the second accommodating part 54. The diameter of the second rod part 62 is larger than the diameter of the first rod part 61. That is, the 1st rod part 61 and the 2nd rod part 62 become a size according to the 1st accommodating part 31 and the 2nd accommodating part 54, respectively. The central axis of the rod 60 and the central axis of the valve body 41 coincide with each other.

An annular groove portion 65 is provided on the outer peripheral surface of the first rod portion 61. An annular seal member 77 is fitted into the groove portion 65, and the space between the inner peripheral surface of the first cylinder 30 and the outer peripheral surface of the first rod portion 61 is sealed by the seal member 77. The first rod portion 61 is guided by the inner peripheral surface of the first housing portion 31 and slides in the axial direction thereof. At this time, the second rod portion 62 moves in the axial direction within the second housing portion 54.

A groove 52 extending in the axial direction of the second housing portion 54 is provided in a part of the inner wall of the second housing portion 54. The groove 52 extends from the vicinity of the overhanging portion 51 to the end portion on the first cylinder 30 side. A pin 72 extending in the outer diameter direction is provided on the outer peripheral edge of the second rod portion 62 of the rod 60. The tip of the pin 72 is inserted into the groove 52, and the second rod portion 62 is movable in the axial direction thereof, and rotation around the axial line is restricted.

In a portion of the second cylinder 50 that faces the groove 52, a sensor insertion port 53 that penetrates the second cylinder 50 in the radial direction is provided. A detection unit 74 a provided at the tip of the photosensor 74 is inserted into the second cylinder 50 from the sensor insertion port 53. A pin 73 extending in the outer diameter direction is provided on the outer peripheral edge of the second rod portion 62 of the rod 60. The tip of the pin 73 is inserted between the light emitting part and the light receiving part of the detecting part 74a, and the light irradiated from the light emitting part is blocked by the pin 73, whereby the fully open position of the valve element 41 is detected. The 1 and 2 show a state in which the valve body 41 is moved to the maximum closing side.

A cylindrical groove 63 is provided on the end surface of the second rod portion 62 on the motor 110 side. The central axis of the groove 63 coincides with the central axis of the second rod portion 62 (first rod portion 61). A spring 71 (elastic member) having a diameter substantially equal to the diameter of the groove 63 is inserted into the groove 63. One end of the spring 71 is in contact with the bottom of the groove 63, and the other end is in contact with the overhang 51. The spring 71 applies an elastic force to the rod 60 and the overhanging portion 51, and moves the rod 60 in a direction in which the rod 60 moves away from the overhanging portion 51, that is, in a direction in which the valve body 41 approaches the valve seat portion 24. .

The portion of the second rod portion 62 that protrudes to the outer diameter side from the first rod portion 61 faces the upper surface of the first cylinder 30. For this reason, when the rod 60 is moved in a direction away from the overhanging portion 51, the second rod portion 62 hits the first cylinder 30 (second restricting portion), and the movement of the rod 60 toward the valve seat portion 24 is restricted. Is done. At this time, the valve element 41 is closest to the valve seat portion 24, and the opening of the flow path 21 is minimized, that is, the flow rate of the liquid flowing out from the outflow port 26 is minimized.

Here, between the 2nd rod part 62 and the 1st cylinder 30, the shim 75 which adjusts the position (2nd control position) which controls the movement to the valve-seat part 24 side of the rod 60 is provided. . FIG. 3A is a side view of the second cylinder 50, and FIG. 3B is a plan view of the shim 75.

As shown in FIG. 3A, the second cylinder 50 is provided with an insertion port 56 that allows a shim 75 (spacer) to be inserted from the outside. The insertion port 56 passes through the inside and outside of the second cylinder 50 and is provided at a portion where the first cylinder 30 and the second cylinder 50 face each other. As shown in FIG. 3B, the shim 75 is formed in a “U” shape, and has a bifurcated portion 75 a inserted between the first cylinder 30 and the second rod portion 62, and an arc shape. Arc portion 75b. The shim 75 is inserted from the insertion port 56 until the arc portion 75 b hits the first rod portion 61 of the rod 60. For this reason, the shim 75 can be inserted from the insertion port 56 after the flow rate adjusting device 10 is assembled.

Then, by adjusting the thickness of the shim 75 inserted between the second rod portion 62 and the first cylinder 30, the position where the movement of the rod 60 toward the valve seat portion 24 is regulated is adjusted. As the shim 75, those having a thickness of 0.2 mm or 0.1 mm are used singly or in combination. In the present embodiment, when the second rod portion 62 is pressed against the first cylinder 30 via the shim 75, the distance (gap) between the valve seat portion 24 and the valve body 41 in the axial direction of the valve body 41 is 0. It is adjusted to be 2mm. The distance between the valve seat portion 24 and the valve body 41 may be adjusted as appropriate according to the application of the flow rate adjustment device 10.

Referring back to FIG. 2, in the second rod portion 62, a portion surrounded by the groove 63 is a female screw portion 64 in which a female screw is cut. The female screw portion 64 is formed in a cylindrical shape and extends in the axial direction of the second rod portion 62. Since the female thread portion 64 and the spring 71 (groove 63) are provided coaxially, the arrangement space in the axial direction of the rod 60 can be reduced.

The drive shaft 111 of the motor 110 is inserted into the third housing portion 55. A first engagement portion 90 is provided on the drive shaft 111. A second engaging portion 80 that engages with the first engaging portion 90 is accommodated across the third accommodating portion 55 and the second accommodating portion 54. The first engaging portion 90 and the second engaging portion 80 are made of a material that can transmit the driving force of the motor 110, for example, stainless steel.

FIG. 4 is an exploded perspective view showing the first engaging portion 90 and the second engaging portion 80.

As shown in the figure, the second engaging portion 80 includes a male screw portion 82 having a male screw cut therein and a head 81 having a diameter larger than that of the male screw portion 82. The second engaging portion 80 has a shape similar to a minus screw as a whole, and a male screw portion 82 extends in the axial direction thereof. The head portion 81 is provided with a groove portion 83 (concave portion) extending in the radial direction. The width and depth of the groove 83 are constant, and the depth of the groove 83 is substantially equal to the thickness of the head 81. The two inner side surfaces 80a of the groove portion 83 are parallel to each other and have the same distance from the central axis of the head portion 81. The central axis of the head 81 coincides with the central axis of the male screw portion 82.

The drive shaft 111 of the motor 110 is provided with a first engagement portion 90 (insertion portion) that is inserted into the groove portion 83 of the second engagement portion 80. The first engaging portion 90 is formed in a rectangular parallelepiped shape, and the center portion in the longitudinal direction is fixed to the drive shaft 111. The first engaging portion 90 includes outer surfaces 90a that are parallel to each other. The thickness of the outer side surface 90 a in the axial direction of the drive shaft 111 is thinner than the thickness of the head 81 of the second engaging portion 80.

The length of the first engaging portion 90 in the longitudinal direction is substantially equal to the diameter of the head 81 in the second engaging portion 80. The width of the first engaging portion 90 is slightly narrower than the width of the groove portion 83 of the second engaging portion 80. Then, in a state where the central axis of the drive shaft 111 of the motor 110 and the central axis of the second engaging portion 80 are aligned, the first engaging portion 90 is inserted into the groove portion 83 along the central axial direction. Thereby, the outer side surface 90a of the first engaging portion 90 and the inner side surface 80a of the groove portion 83 are fitted with a gap.

2, the first engaging portion 90 and the second engaging portion 80 can be relatively moved in the axial direction of the drive shaft 111 and can transmit a rotational force to each other. The male screw portion 82 of the second engaging portion 80 is engaged with the female screw portion 64 of the second rod portion 62 (rod 60). The rod 60 is pushed toward the valve seat 24 by a spring 71. The second engaging portion 80 is connected to the rod 60 via the male screw portion 82 and the female screw portion 64. For this reason, the second engaging portion 80 is pulled in the direction of the valve seat portion 24 by the rod 60. When the second engagement portion 80 is moved in the direction of the valve seat portion 24, the head 81 of the second engagement portion 80 hits the overhang portion 51 (first restriction portion), and the second engagement portion 80 is moved. Movement toward the valve seat 24 is restricted.

A thrust washer 76 that receives a force acting in the axial direction of the second engagement portion 80 is provided between the second engagement portion 80 and the overhang portion 51. For this reason, when the 2nd engaging part 80 rotates centering on the external thread part 82, the head 81 and the thrust washer 76 will slide smoothly. Further, the force that pulls the second engagement portion 80 in the direction of the valve seat portion 24 is received by the overhang portion 51 and the thrust washer 76. The position where the movement of the second engagement portion 80 is restricted corresponds to the first restriction position.

The central axes of the valve body 41, the rod 60, the second engagement portion 80, and the drive shaft 111 all coincide. The male screw portion 82 of the second engaging portion 80 and the female screw portion 64 of the rod 60 are relatively screw-fed in the axial direction of the drive shaft 111 by relatively rotating. That is, the distance between the head 81 of the second engaging portion 80 and the second rod portion 62 of the rod 60 by the second engaging portion 80 being rotated by the drive shaft 111 via the first engaging portion 90. Is changed. FIG. 2 shows a state where the rotational position (number of steps) of the drive shaft 111 of the motor 110 is the reference position (reference step number). In this state, the second rod portion 62 of the rod 60 contacts the shim 75 and the head 81 of the second engagement portion 80 contacts the thrust washer 76. A gap (space) is formed between the bottom portion of the first engagement portion 90 and the bottom portion of the groove portion 83 of the second engagement portion 80.

Next, with reference to FIG. 5, the operation of increasing the opening degree of the flow path 21 by the valve body 41 in the flow rate adjusting device 10 will be described. The driving of the drive shaft 111 of the stepping motor 110 is controlled by the controller.

Rotational force is transmitted from the first engaging portion 90 to the second engaging portion 80 by rotating the drive shaft 111 in the direction of the arrow in the figure. The second engaging portion 80 is pulled in the direction of the valve seat portion 24 by the elastic force of the spring 71, and its movement is restricted by the thrust washer 76 and the overhang portion 51. Further, the rotation of the rod 60 in the rotation direction of the drive shaft 111 is restricted by a pin 72 inserted in the groove 52 of the second cylinder 50.

Therefore, by rotating the male screw portion 82 of the second engagement portion 80, the female screw portion 64 is screw-fed in a direction approaching the drive shaft 111, and the head 81 of the second engagement portion 80 and the second rod of the rod 60 are fed. The part 62 will approach. As a result, the rod 60 is moved in the direction of the arrow in the drawing, and the valve body 41 is moved in a direction away from the valve seat portion 24 accordingly. For this reason, the distance between the valve seat portion 24 and the valve body 41, that is, the opening degree of the flow path 21 is adjusted, and the flow rate of the liquid flowing out to the flow path 23 is adjusted.

Here, since the first engaging portion 90 and the second engaging portion 80 are relatively movable in the axial direction of the drive shaft 111, the reaction of the force when the rod 60 is screwed in the axial direction. Can be prevented from acting on the drive shaft 111 in the axial direction. Moreover, since the rotational position of the drive shaft 111 is precisely controlled based on the number of steps of the motor 110, the opening degree of the flow path 21 can be precisely controlled.

Further, when the rod 60 is further moved and the pin 73 is detected by the detection unit 74a of the photosensor 74, it is determined that the valve body 41 has reached the fully open position, and the rotation of the drive shaft 111 is stopped. Let At this time, a gap is formed between the second rod portion 62 of the rod 60 and the overhang portion 51. That is, the rod 60 can be moved in the direction of the arrow in the drawing until the second rod portion 62 hits the overhanging portion 51, but when the fully open position of the valve body 41 is detected by the detecting portion 74a. Further movement of the rod 60 is prohibited. For this reason, it can prevent that the rod 60 contacts the overhang | projection part 51, and can suppress that an excessive load is applied to the motor 110. FIG.

With reference to FIG. 6, the operation | movement which makes the opening degree of the flow path 21 small by the valve body 41 in the flow volume adjustment apparatus 10 is demonstrated. The driving of the drive shaft 111 of the stepping motor 110 is controlled by the controller.

Rotational force is transmitted from the first engaging portion 90 to the second engaging portion 80 by rotating the drive shaft 111 in the direction of the arrow in the figure (the reverse direction of FIG. 5). In this case, by rotating the male screw portion 82 of the second engagement portion 80, the female screw portion 64 is screw-fed in a direction approaching the valve seat portion 24, and the head 81 and the rod 60 of the second engagement portion 80 are rotated. The 2nd rod part 62 of this will leave | separate. As a result, the rod 60 is moved in the direction of the arrow in the figure (the reverse direction in FIG. 5), and accordingly, the valve body 41 is moved in a direction approaching the valve seat portion 24. For this reason, the distance between the valve seat portion 24 and the valve body 41, that is, the opening degree of the flow path 21 is adjusted, and the flow rate of the liquid flowing out to the flow path 23 is adjusted.

When the second rod portion 62 of the rod 60 hits the shim 75 and the movement of the rod 60 is restricted by the shim 75 and the first cylinder 30, the valve body 41 is brought closest to the valve seat portion 24. When the drive shaft 111 is further rotated from this state, the head 81 of the second engaging portion 80 and the second rod portion 62 of the rod 60 are relatively screw-fed. Here, the first engaging portion 90 and the second engaging portion 80 are relatively movable in the axial direction of the drive shaft 111, and movement of the rod 60 in the direction of the valve seat portion 24 is restricted. For this reason, by the rotation of the drive shaft 111 and the second engaging portion 80, the second engaging portion 80 is moved in the direction in which the head 81 moves away from the thrust washer 76 and the overhanging portion 51, that is, in the direction of the arrow in the figure.

Therefore, even if the movement of the rod 60 is restricted and the valve body 41 is closest to the valve seat part 24, the rotation of the second engagement part 80 and the drive shaft 111 is not restricted. For this reason, it can suppress that an excessive load is applied to the motor 110, and can suppress the motor 110 from stepping out. Here, since a space is provided between the bottom portion of the first engaging portion 90 and the bottom portion of the groove portion 83, even if the drive shaft 111 is rotated in a state where the movement of the rod 60 is restricted, The second engagement portion 80 can be sufficiently released in the direction of the motor 110.

In addition, as shown in FIG. 1, the 2nd engaging part 80 can be exposed by removing the housing 120 and the motor 110 from the flow volume adjustment apparatus 10. FIG. For this reason, the 2nd engaging part 80 can be easily rotated manually, and it becomes possible to adjust the position of the valve body 41 manually. For this reason, the maintainability of the flow control device 10 can be improved.

The embodiment described above has the following advantages.

The first engaging portion 90 and the second engaging portion 80 are relatively movable in the axial direction of the drive shaft 111. For this reason, when the movement of the rod 60 is restricted, the direction in which the head 81 of the second engagement portion 80 moves away from the second rod portion 62 of the rod 60 by rotating the second engagement portion 80. That is, the head 81 of the second engagement portion 80 is screwed in a direction away from the overhanging portion 51. Therefore, even if the motor 110 is further driven from the state in which the movement of the rod 60 is restricted, it is possible to prevent an excessive load from being applied to the motor 110. As a result, the motor 110 can be prevented from stepping out, and the position adjustment accuracy of the valve body 41 can be prevented from decreasing. Further, damage or the like of the motor 110 can be suppressed.

Further, the first engagement portion 90 and the second engagement portion 80 transmit rotational force to each other, while the first engagement portion 90 and the second engagement portion 80 are relatively movable in the axial direction of the drive shaft 111. It has become. For this reason, the reaction of the force of screw feeding the rod 60 in the axial direction and the reaction of the force of screw feeding the head 81 of the second engagement portion 80 away from the overhanging portion 51 are the drive shaft 111 of the motor 110. Can be prevented from acting in the axial direction. As a result, an increase in the rotational load of the motor 110 can be suppressed, and the durability of the motor 110 can be reduced and the increase in size of the motor 110 can be suppressed.

The second restricting position is adjusted by the shim 75 on the upper surface portion of the first cylinder 30 that restricts the movement of the rod 60 toward the valve seat 24 from the second restricting position. For this reason, the distance between the valve seat portion 24 and the valve body 41, that is, the flow state of the liquid can be precisely controlled in the state where the valve body 41 is closest to the valve seat portion 24. Further, since the clearance is provided between the valve seat portion 24 and the valve body 41 in a state where the movement of the rod 60 is restricted by the upper surface portion of the first cylinder 30, the valve body 41 hits the valve seat portion 24. You can avoid that. As a result, it is effective that the valve body 41 is strongly pressed against the valve seat portion 24, particles are generated from the valve body 41 and the valve seat portion 24, and the valve body 41 and the valve seat portion 24 are deformed or damaged. Can be suppressed.

· The movement of the rod 60 in the axial direction is guided by the first cylinder 30 and the second cylinder 50. The shim 75 can be inserted from the outside of the first cylinder 30 through the insertion port 56. For this reason, after assembling the flow rate adjusting device 10, the interval between the valve seat portion 24 and the valve body 41 can be precisely adjusted by the shim 75. Therefore, it is not necessary to require high dimensional accuracy for the valve body 20, the first cylinder 30, the rod 60, and the like, and it is possible to maintain the liquid control accuracy while suppressing costs.

In the axial direction of the drive shaft 111, the rectangular parallelepiped insertion portion provided in the first engagement portion 90 can be inserted into the groove portion 83 provided in the second engagement portion 80. And the mutually parallel outer side surface 90a of the 1st engaging part 90 and the inner side surface 80a of the groove part 83 are fitted in the state with a clearance gap. Therefore, the functions of the first engaging portion 90 and the second engaging portion 80 can be realized with a simple configuration.

The present invention is not limited to the above embodiment, and can be implemented as follows, for example.

In the above embodiment, the insertion portion is provided in the first engagement portion 90 and the groove portion 83 (recess portion) is provided in the second engagement portion 80. However, the groove portion (recess portion) is provided in the first engagement portion 90. In addition to the provision, an insertion portion may be provided in the second engagement portion 80.

The first engaging portion 90 and the second engaging portion 80 can be moved relative to each other in the axial direction of the drive shaft 111 of the motor 110 and can transmit rotational force to each other. The shape can be arbitrarily changed.

In the above-described embodiment, the male thread portion 82 is provided in the second engaging portion 80 and the female screw portion 64 is provided in the rod 60. However, the female screw portion 64 is provided in the second engaging portion 80 and the male screw is provided in the rod 60. A portion may be provided.

A configuration in which the valve body 41 contacts the valve seat portion 24 in a state where the valve body 41 is closest to the valve seat portion 24 may be employed. Even in such a configuration, the valve element 41 is strongly pressed against the valve seat portion 24 and an excessive load is applied to the motor 110 by releasing the second engaging portion 80 in the direction of the motor 110. be able to.

· Not limited to the spring 71, an elastic member such as a rubber material, a configuration using a repulsive force by a magnet, or the like may be adopted.

A motor other than the stepping motor 110, such as a servo motor or a DC motor, may be employed.

· Not limited to the flow rate adjusting device 10, it can be embodied as a pressure adjusting device for adjusting the pressure of the fluid. Further, the fluid is not limited to liquid, and gas can also be used.

DESCRIPTION OF SYMBOLS 10 ... Flow control apparatus, 20 ... Valve body, 21, 23 ... Flow path, 22 ... Valve chamber, 24 ... Valve seat part, 30 ... 1st cylinder, 41 ... Valve body, 50 ... 2nd cylinder, 51 ... Overhang , 60... Rod, 64... Female threaded portion, 80... Second engaging portion, 82... Male threaded portion, 90.

Claims

A motor having a drive shaft;
A first engagement portion provided on the drive shaft;
A second engagement portion that moves relative to the first engagement portion along the axial direction of the drive shaft and receives a rotational force from the first engagement portion;
A valve body provided with a fluid flow path and a valve seat; and
A valve body that is provided to face the valve seat portion and adjusts the opening of the flow path;
A moving member coupled to the valve body, allowed to move in the axial direction, and restricted from rotating about the axis;
An elastic member that applies a force to the moving member in a direction in which the valve body approaches the valve seat portion;
A first restricting portion that restricts movement of the second engaging portion toward the valve seat portion from a first restricting position;
A second restricting portion for restricting the movement member from moving to the valve seat portion side from a second restricting position;
With
The second engaging portion and the moving member are screwed to each other, thereby relatively moving the moving member and the second engaging portion along the axial direction by relative rotation. A fluid control device.
The second restriction portion is provided with a spacer for adjusting the second restriction position,
2. The fluid control device according to claim 1, wherein a gap is provided between the valve seat portion and the valve body in a state where movement of the moving member is restricted by the second restricting portion. .
A cylinder for guiding the movement of the moving member in the axial direction;
The fluid control device according to claim 2, wherein the cylinder is provided with an insertion port through which the spacer can be inserted from the outside.
One of the first engagement portion and the second engagement portion includes a rectangular parallelepiped insertion portion, and the other includes a recess that allows the insertion portion to be inserted in the axial direction. The fluid control device according to any one of claims 1 to 3, wherein the parallel outer surface and the inner surface of the recess are fitted with a gap.
The fluid control device according to any one of claims 1 to 4, wherein the motor is a stepping motor that rotates in synchronization with pulse power.