JP2015215051A - Control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control valve which can achieve improvement of reliability of an operation and reduction in cost, while achieving simplification of piping in an automatic measurement system and facilitation of maintenance.SOLUTION: A control valve 10 includes: a valve body 16 arranged in a body 15; a first actuator 20 connected to the valve body via a rotation support shaft 17 so that it can transmit power; and a second actuator 40 connected to the valve body via the first actuator and the rotation support shaft so that it can transmit power. The valve body 16 is provided so as to be switched in one position out of a fully closed position, an intermediate opening position and a fully open position by the rotation in a predetermined angle range around the rotation support shaft 17. The first actuator 20 is for switching the valve body 16 into the fully closed position or the fully open position, and the second actuator 40 is for switching the valve body 16 into the intermediate opening position.

Description

  The present invention relates to a control valve equipped in an automatic fluid metering system.

  Conventionally, as an automatic fluid metering system, a large-diameter valve 3 and a small-diameter valve 4 are arranged in parallel between a pump 1 and a metering tank 2 as shown in FIG. Is.

  In this type of automatic metering system, when supplying a target amount of fluid from the pump 1 to the metering tank 2, first, as shown in FIG. 7, the large-diameter valve 3 is opened and the small-diameter valve 4 is opened. By closing, it supplies with a large flow rate. Then, when the target amount is about 90%, the large-diameter valve 3 is closed and the small-diameter valve 4 is opened to supply at a small flow rate, and when the target amount is reached, the small-diameter valve 4 is closed. It is common.

  However, the conventional automatic weighing system has a problem that piping is complicated. In addition, in the case of a paint that tends to harden when the fluid comes into contact with air, there is a problem that the paint accumulates on the outflow side of each valve 3, 4, and maintenance is troublesome for the number of valves 3, 4.

  On the other hand, as a control valve, for example, as described in Patent Document 1, a valve that can take an intermediate opening position in addition to a fully closed position and a fully open position is known. It is conceivable that this control valve is arranged between the pump 1 and the metering tank 2 instead of the two valves 3 and 4 having different diameters as shown in FIG.

  However, since the conventional control valve stops the valve body at the intermediate opening position by control, it requires a device such as a sensor, which increases the cost and the operational reliability. There is a problem of lacking.

JP 2014-47853 A

  The present invention has been made in view of the above points, and its problem is to easily and reliably switch the valve body to any one of the fully closed position, the intermediate opening position, and the fully opened position using two actuators. Configure to get. Accordingly, an object of the present invention is to provide a control valve capable of improving the reliability of operation and reducing the cost while simplifying piping and facilitating maintenance in an automatic weighing system.

  In order to solve the above-mentioned problems, the present invention is arranged as a control valve in a body, and is located at any one of a fully closed position, an intermediate opening position and a fully opened position by rotation within a predetermined angle range around a rotation support shaft. A valve body provided to be switchable to the valve body, a first actuator connected to the valve body through the rotation support shaft so as to be able to transmit power, and for switching the valve body to a fully closed position or a fully open position, A first actuator and a second actuator that is connected to the valve body through the rotation support shaft so as to be able to transmit power and switch the valve body to an intermediate opening position.

  According to the control valve of the present invention, since the valve body can be switched to any one of the fully closed position, the intermediate opening position, and the fully opened position, the piping of the automatic fluid measurement system can be simplified and maintained. Simplification can be achieved. In addition, the position of the valve body can be easily and reliably switched by the two actuators, and equipment such as a sensor for position switching is not required, which contributes to the improvement of operation reliability and cost reduction. be able to.

FIG. 1 is a block diagram of an automatic fluid metering system equipped with a control valve according to an embodiment of the present invention. FIG. 2 is a side view with a part cut away showing the overall configuration of the control valve. 3 is a cross-sectional view taken along line XX of FIG. 2 when the control valve is switched to the fully closed position. FIG. 4 is a view corresponding to FIG. 3 when the control valve is switched to the fully open position. FIG. 5 is a view corresponding to FIG. 3 when the control valve is switched to the intermediate opening position. FIG. 6 is a view corresponding to FIG. FIG. 7 is a time chart of the flow rate in the automatic fluid metering system.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments that are modes for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 shows the overall configuration of an automatic fluid metering system equipped with a control valve according to an embodiment of the present invention. In this automatic metering system, one control valve 10 according to an embodiment of the present invention is arranged in series between a pump 1 and a metering tank 2.

  As shown in FIG. 2, the control valve 10 includes a valve main body 11 formed of a ball valve that controls a fluid, and an air-driven actuator unit 12 that is a driving unit of the valve main body 11. The valve body 11 includes a body 15 having an inlet 13 and an outlet 14, a ball valve body 16 disposed in the body 15, and one end (lower end) as a rotation support shaft of the ball valve body 16. And a stem 17 connected to each other. The ball valve body 16 has a communication port 18 and can be switched to a fully closed position, an intermediate opening position, or a fully opened position by rotation within a predetermined angle (specifically, 90 degrees) around the stem 17. Is provided. The fully open position is a position where the communication port 18 of the ball valve body 16 completely coincides with the inlet 13 and the outlet 14 of the body 15, and the fully closed position is the flow of the communication port 18 of the ball valve body 16 and the flow of the body 15. It is a position where the inlet 13 and the outlet 14 do not completely coincide. The intermediate opening position is a position where the communication port 18 of the ball valve body 16 partially coincides with the inlet 13 and the outlet 14 of the body 15.

  As shown in FIG. 3, the actuator unit 12 includes a first actuator 20 for switching the ball valve body 16 to a fully closed position or a fully opened position, and a second actuator for switching the ball valve body 16 to an intermediate opening position. And an actuator 40. The first actuator 20 is connected to the ball valve body 16 through the stem 17 so that power can be transmitted, while the second actuator 40 is connected to the ball valve body 16 through the first actuator 20 and the stem 17. It is connected so that power can be transmitted.

  That is, the first actuator 20 includes a cylinder 21, a pinion gear 22 disposed in the cylinder 21, and a rack gear 23 disposed along the axial direction in the cylinder 21 and meshing with the pinion gear 22. The pinion gear 22 is connected to the stem 17 via a gear shaft 24 so as to rotate integrally. When the pinion gear 22 rotates 90 degrees about the gear shaft 24, the ball valve body 16 is switched to the fully closed position or the fully opened position. It is supposed to be. Although not shown, both ends of the gear shaft 24 are rotatably supported by the cylinder 21, and one end (upper end) of the gear shaft 24 extends to the outside of the cylinder 21 as shown in FIG. (To extend).

  The first actuator 20 further includes a pair of pistons 25 and 26 that are slidable (contactable and slidable) in the cylinder 21 with both ends of the rack gear 23 supported. . The space in the cylinder 21 is partitioned into three spaces 27, 28 and 29 by a pair of pistons 25 and 26. The space 27 is a space sandwiched between the pair of pistons 25 and 26 and houses the rack gear 23 and the like. The space 28 is an air chamber on the opposite side of the rack gear 23 of one piston 26 of the pair of pistons 25, 26, and the space 29 is a spring chamber on the opposite side of the rack gear 23 of the other piston 25.

  Although not shown, air (specifically compressed air) is supplied to or discharged from the air chamber 28 through an air supply / exhaust port 31 provided in the cylinder 21. A coil spring 32 is disposed between the end surface portion of the cylinder 21 and the piston 25. When air is supplied into the air chamber 28 from the air supply / exhaust port 31, the pair of pistons 25, 26 move in a direction to compress the compression coil spring 32 and reduce the spring chamber 29 (see FIG. 4). The power accompanying this movement is transmitted as a rotational force to the stem 17 or the ball valve body 16 via the rack gear 23, the pinion gear 22 and the gear shaft 24, and the ball valve body 16 is switched to the fully open position. When the air in the air chamber 28 is discharged from the air supply / exhaust port 31, the pair of pistons 25, 26 move in a direction to reduce the air chamber 28 by the urging force of the compression coil spring 32. The power accompanying this movement is transmitted as a rotational force to the stem 17 or the ball valve body 16 through the rack gear 23, the pinion gear 22 and the gear shaft 24, and the ball valve body 16 is switched to the fully closed position. Note that the movement range of the pair of pistons 25 and 26 in the cylinder 21 is regulated by the piston 25 or 26 coming into contact with the end face of the cylinder 21 or the stepped portion 56.

  On the other hand, the second actuator 40 has a cylinder 41, a piston 42 slidably disposed in the cylinder 41, and a rod 43 fixed to the piston 42 in a state of passing through the center line of the piston 42. ing. The cylinder 41 of the second actuator 40 is connected on the same axis to the air chamber 28 side of the cylinder 21 of the first actuator 20, and the internal space of both the cylinders 41 and 21 is the same as that of the second actuator 40. The cylinder 41 is partitioned by an end surface portion 41a. One end of the rod 43 extends through the end surface 41 a of the cylinder 41 to the air chamber 28 side of the cylinder 21 of the first actuator 20.

  The piston 42 of the second actuator 40 passes through the cylinder 41 in the spring chamber 44 close to the first actuator 20 (the rod 43 extending side of the piston 42) and the opposite side of the first actuator 20 (the rod 43 of the piston 42). It is partitioned into an air chamber 45 on the side opposite to the extending side. A compression coil spring 46 is disposed in the spring chamber 44 between the end surface portion 41 a of the cylinder 41 and the piston 42. Although not shown, air (more specifically, compressed air) is supplied to or discharged from the air chamber 45 through an air supply / exhaust port 47 provided in the cylinder 41. When air is supplied into the air chamber 45 from the air supply / discharge port 47, the piston 42 slides in the cylinder 41 toward the spring chamber 44 (see FIG. 5). As a result, the extended end side of the rod 43 (more specifically, a stopper portion 52 of the screw shaft 51 described later) abuts on one piston 26 constituting the air chamber 28 of the first actuator 20, and the piston 26 is pressed and moved. The ball valve body 16 is switched from the fully closed position to the intermediate opening position.

  The rod 43 of the second actuator 40 is formed of a circular pipe, and the other end of the rod 43 extends from the air chamber 45 in the cylinder 41 to the outside of the cylinder 41 through the end surface 41b of the cylinder 41. Yes. Here, both end portions of the rod 43 are provided so as to penetrate the end surface portions 41 a and 41 b of the cylinder 41, respectively, and the sliding smooth member 48 for smooth sliding of the rod 43 in the through portions. Etc. are provided.

  The second actuator 40 further includes an adjustment mechanism 50 for finely adjusting the intermediate opening position of the ball valve body 16. The adjustment mechanism 50 includes a ball screw mechanism that screw-feeds a screw shaft 51 that is disposed through the rod 43. Although not shown, the adjusting mechanism 50 has a nut provided on the rod 43 side and a number of hard spheres arranged in the screw groove of the screw shaft 51 or in the screw groove of the nut. doing. One end of the screw shaft 51 protrudes from the one end of the rod 43 toward the air chamber 28 side of the cylinder 21 of the first actuator 20, and one end of the screw shaft 51 contacts the piston 26 of the first actuator 20. A stopper portion 52 is formed. On the other hand, the other end of the screw shaft 51 protrudes from the other end of the rod 43, and an operation portion 53 for rotating the screw shaft 51 is provided at the protruding portion. Then, a rotary operation tool is attached to the operation portion 53 to rotate the screw shaft 51, and the screw shaft 51 is screwed by the adjusting mechanism 50 so that the stopper portion 52 of the screw shaft 51 is leftward in FIG. The intermediate opening of the ball valve body 16 is increased.

  In FIG. 3, 55 is formed around a through hole through which the rod 43 on the side surface facing the air chamber 28 of the first actuator 20 out of the end surface portion 41 a of the cylinder 41 of the second actuator 40. It is a concave part. When the piston 42 of the second actuator 40 is located at a position where the air chamber 45 is contracted, the one end of the rod 43 and the stopper portion 52 of the screw shaft 51 are retracted into the recess 55, and the first actuator The 20 pistons 26 are not brought into contact with each other.

  Next, the operation of the automatic weighing system will be described. When supplying a target amount of fluid from the pump 1 to the metering tank 2 through the control valve 10, first, the ball valve body 16 of the control valve 10 is switched from the fully closed position to the fully open position. This switching is performed by supplying air from the air supply / exhaust port 31 into the air chamber 28 of the first actuator 20. When the ball valve body 16 of the control valve 10 is switched to the fully open position, fluid is supplied to the metering tank 2 with a large flow rate.

  When the target amount reaches about 90%, the ball valve body 16 of the control valve 10 is switched from the fully open position to the intermediate opening position. This switching is performed by supplying air from the air supply / exhaust port 47 into the air chamber 45 of the second actuator 40 and exhausting air from the air chamber 28 of the first actuator 20 from the air supply / exhaust port 31. Done. When the ball valve body 16 of the control valve 10 is switched to the intermediate opening position, the fluid is supplied to the measuring tank 2 with a small flow rate.

  Thereafter, when the fluid in the measuring tank 2 reaches the target amount, the ball valve body 16 of the control valve 10 is switched from the intermediate opening position to the fully closed position. This switching is performed by discharging the air in the air chamber 45 of the second actuator 40 from the air supply / discharge port 47. When the ball valve body 16 of the control valve 10 is switched to the fully closed position, the supply of fluid to the measuring tank 2 is shut off.

  As described above, according to the control valve 10 according to the embodiment of the present invention, the ball valve body 16 can be switched to any one of the fully closed position, the intermediate opening position, and the fully opened position. Therefore, piping is not complicated as in the case where two valves 3 and 4 having different diameters are arranged in parallel between the pump 1 and the metering tank 2 as in the conventional automatic metering system shown in FIG. Piping can be simplified. Even in the case of a paint that tends to harden when the fluid comes into contact with air, the automatic metering system only arranges one control valve 10 between the pump 1 and the metering tank 2. Maintenance work for the deposition of paint becomes easier than in the conventional case.

  In addition, the position of the ball valve body 16 is switched by two air-driven actuators 20 and 40. Of the two actuators 20 and 40, the first actuator 20 is connected to the ball valve body 16 via the stem 17 so as to transmit power in order to switch the ball valve body 16 to the fully closed position or the fully opened position. . The second actuator 40 is coupled to the ball valve body 16 via the first actuator 20 and the stem 17 so as to be able to transmit power to switch the ball valve body 16 to the intermediate opening position. For this reason, the position switching of the ball valve body 16 can be easily and reliably performed by the two actuators 20 and 40. In addition, since a device such as a sensor for switching the position is not required, it is possible to contribute to both improvement in operation reliability and cost reduction.

  In particular, in the present embodiment, the second actuator 40 has an adjustment mechanism 50 for finely adjusting the intermediate opening position of the ball valve body 16, so that it is easy to use and has excellent practicality. It plays.

  In addition, this invention is not limited to the said embodiment, A various other form is included. For example, in the above-described embodiment, the case where a ball valve is used as the valve body 11 has been described. However, the present invention is not limited to this case, and is similarly applied to a case where a butterfly valve or the like is used instead of the ball valve. Can do.

  Further, the configuration of the two air-driven actuators 20 and 40 is not limited to that of the above-described embodiment, but includes various forms. For example, in the first actuator 20, the air chamber 28 and the spring chamber 29 are provided in the cylinder 21. However, instead of the spring chamber 29, a second air chamber is provided separately from the first air chamber. Anyway.

10 Control valve 15 Body 16 Ball valve body 17 Stem (rotating spindle)
20 First actuator 21 Cylinder 22 Pinion gear 23 Rack gear 25, 26 Piston 28 Air chamber (space)
29 Spring room (space)
Reference Signs List 31 Air supply / exhaust port 32 Compression coil spring 40 Second actuator 41 Cylinder 41a, 41b End face 42 Piston 43 Rod 44 Spring chamber 45 Air chamber 46 Compression coil spring 47 Air supply / exhaust port 50 Adjustment mechanism (ball screw mechanism)
51 Screw shaft 53 Operation section

Claims (4)

A valve body disposed within the body and provided so as to be switchable to any of a fully closed position, an intermediate opening position, and a fully opened position by rotation within a predetermined angular range around the rotation support shaft;
A first actuator connected to the valve body via the rotary support shaft so as to be able to transmit power, and for switching the valve body to a fully closed position or a fully open position;
And a second actuator connected to the valve body through the first actuator and the rotation support shaft so as to be able to transmit power, and for switching the valve body to an intermediate opening position. valve.   The control valve according to claim 1, wherein the second actuator has an adjustment mechanism for finely adjusting an intermediate opening position of the valve body.   The first actuator includes a cylinder, a pinion gear disposed in the cylinder and coupled to the rotary support shaft so as to rotate together, a rack gear disposed along the axial direction in the cylinder and meshed with the pinion gear, Air is supplied to and discharged from a pair of pistons slidably disposed in the cylinder with both ends of the rack gear supported, and an air chamber on the opposite side of the rack gear of one of the pair of pistons. And an air supply / exhaust port provided to perform the operation, and a spring disposed in a spring chamber on the opposite side of the rack gear of the other piston of the pair of pistons, into the air chamber from the air supply / exhaust port. When air is supplied, the valve body is switched to the fully open position, and when the air in the air chamber is discharged from the air supply / discharge port, the valve body is switched to the fully closed position. Control valve according to claim 1, wherein is provided in so that. The second actuator is fixed to the piston, a cylinder connected on the same axis to the air chamber side of the cylinder of the first actuator, a piston slidably disposed in the cylinder, and the piston. And a rod extending through one end surface of the cylinder to the air chamber side of the cylinder of the first actuator, and an air chamber opposite to the rod extending side of the piston. An air supply / exhaust port provided for supplying and discharging air and a spring disposed in a spring chamber on the rod extension side of the piston, and supplying air into the air chamber from the air supply / exhaust port When the piston slides in the cylinder toward the spring chamber side, the extended end side of the rod comes into contact with one piston constituting the air chamber of the first actuator, Serial control valve according to claim 3, wherein said valve body is pressed against moving the piston is provided to switch from the fully closed position to an intermediate opening position.

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