JP5314121B2 - Scotch yoke actuator - Google Patents

Description

  The present invention relates to a scotch yoke type operating device capable of improving output torque as compared with a conventional operating device as an operating device for operating a valve provided in a pipeline or the like.

  The scotch yoke type actuator is housed in a casing 9 as shown in FIG. 8 as a conventional system, and a scotch yoke 2 is attached to an end of a valve stem 1 for opening and closing a valve such as a pipeline. A transmission pin 3 provided on a guide block 4 fixedly attached to a rod 5 is slidably engaged in a long hole 22 along a longitudinal axis passing through the center of the valve stem 1 of the scotch yoke 2. Both ends of the guide block 4 are attached to the pistons 71 and 81 which are moved by fluid pressure in the cylinders 72 and 82 of the pneumatic actuators 7 and 8 provided on both sides of the casing 9 and are slidably supported by the casing 9. The rod 5 is moved in the axial direction. Further, the guide block 4 is provided so that both ends thereof are slidably supported by guide rods 6 fixed to the casing 9.

  In such a conventional scotch yoke type actuator, the rod 5 swings the scotch yoke 2 via the transmission pin 3 to apply a rotational force to the valve stem 1 to open and close the valve, and the guide rod 6 Is arranged in parallel with the rod 5 and integrally prevents the rod 6 from bending. For this purpose, the transmission block 4 is connected to the rod 5 that operates integrally with the pistons 71 and 81 by using the transmission pin 3 corresponding to the strength.

  In the Scotch yoke type operating device as described above, the piston rod 5 and the transmission block 4 integrated therewith do not directly swing the Scotch yoke 3. Since the scotch yoke 3 is oscillated through the transmission block 4 directly fixed to the rod 5 with the pin 3, the rotation radius is not sufficient, the output torque is limited, and the scale of the device itself is increased. There was a problem that it ended up.

  The present invention has been made to solve the above-mentioned problems. The output torque obtained by swinging and rotating the scotch yoke by sliding the guide block is higher than that of the conventional actuator. It is an object of the present invention to provide a scotch yoke type actuator.

A Scotch yoke type actuator according to the present invention is a Scotch yoke type actuator that opens and closes a valve by rotating a stem of a valve provided in a pipeline or the like,
A casing for housing the main part of the actuator,
A scotch yoke that swings about the valve stem so that an end of the valve stem is fixed to open and close the valve stem;
A transmission block that is slidably supported to oscillate the scotch yoke, and has a pressing portion provided oppositely in contact with the vicinity of the other end of the scotch yoke;
Both ends of the casing are fixed to a guide rod for slidably supporting the transmission block. The guide rod is fixed to the transmission block and slidably moves along the guide rod. An actuator comprising a rod, a piston in a cylinder provided on at least one side wall of the casing, and an end of the rod being fixed and operating by fluid pressure, a ram rod, and the like;
Is included.

  In the scotch yoke type operating device, a guide rod for guiding the transmission block is disposed on the remote side of the swing radius of the scotch yoke and positioned and fixed to the casing. The rod is fitted and fixed to the transmission block. And slidably supported on the side wall of the casing.

  Further, in the Scotch yoke type actuator, an actuator that slides the rod is provided on both side walls of the casing, and one of the actuators can act as an actuator for opening the valve, and the other of the actuators Can be used for closing the valve.

  The actuator of the Scotch-yoke type actuator is provided on one side wall, and operates by switching the fluid pressure on both sides of the piston of the actuator to supply and exhaust air.

  Further, the scotch yoke type operating device is provided with a set bolt that protrudes to the inside of the side wall of the casing, and is set so as to avoid a collision with the side wall of the transmission block by the set bolt. It is characterized by being.

  Further, in the scotch yoke type operating device, the scotch yoke is provided such that the scotch yoke is sandwiched between the pressing portions of the transmission block, and a reinforcing portion wider than the width of the portion of the pressing portion for reinforcing the strength thereof. Is provided integrally with the scotch yoke.

  A scotch yoke type actuating device according to the present invention is a scotch yoke type actuating device that opens and closes a valve by rotating a stem of a valve provided in a pipeline or the like, and a casing that houses a main part of the actuating device, A scotch yoke that swings about the valve stem so that an end is fixed to the valve stem and opens and closes the valve stem, and is slidably supported to swing the scotch yoke, and the scotch yoke A transmission block having a pressing portion provided oppositely in contact with the vicinity of the other end of the guide, a guide rod for slidably supporting the transmission block with both ends fixed to the casing, and the transmission block A fixed rod for slidably moving the transmission block along the guide rod, and the casing A transmission block which is provided on at least one of the side walls and includes a piston in a cylinder in which an end portion of the rod is fixed and is operated by fluid pressure, an actuator composed of a ram type rod, etc. By swinging the scotch yoke by the pressing portion, an output torque for rotating the valve stem is obtained, and a strength superior to that of the conventional device by pin engagement between the scotch yoke and the rod is obtained. .

  In the scotch yoke type actuator, a guide rod for guiding the transmission block is disposed on the remote side of the swing radius of the scotch yoke and positioned and fixed to the casing, and the rod is fitted with the transmission block. Since it is fixed and slidably supported on the side wall of the casing, the sliding motion by the rod of the transmission block is stabilized, and the rocking motion of the scotch yoke is increased with the valve stem as the center. A high output torque due to the radius of rotation can be obtained within the possible range.

  Further, in the Scotch yoke type actuator, an actuator that slides the rod is provided on both side walls of the casing, and one of the actuators can act as an actuator for opening the valve, and the other of the actuators Can be used for closing the valve, so that the sliding movement of the rod can be caused by the respective actuators to open or close the valve, and a reliable valve opening / closing operation can be provided.

  The actuator of the scotch yoke type actuator is provided on one side wall and can be operated by switching the fluid pressure on both sides of the piston of the actuator and supplying and exhausting air. The equipment can be operated in the facility.

  Further, the scotch yoke type operating device is provided with a set bolt that protrudes to the inside of the side wall of the casing, and is set so as to avoid a collision with the side wall of the transmission block by the set bolt. Therefore, in addition to being a safety device, it is possible to restrict the sliding movement of the rod that gives the rocking movement of the Scotch yoke inside the casing to a required predetermined range.

  Further, in the scotch yoke type operating device, the scotch yoke is provided such that the scotch yoke is sandwiched between the pressing portions of the transmission block, and a reinforcing portion wider than the width of the portion of the pressing portion for reinforcing the strength thereof. Since the scotch yoke is provided integrally with the scotch yoke, the strength of the scotch yoke itself can be increased, and the strength of the scotch yoke can be adjusted according to the load of the valve rotation.

It is a fragmentary sectional view of a Scotch yoke type actuator by a form for carrying out the present invention. It is a perspective view of the scotch yoke used for the scotch yoke type actuator by this invention. FIG. 3 is a perspective view of a transmission block that operates in combination with the scotch yoke shown in FIG. 2. FIG. 3 is a perspective view of an end portion of a reinforced scotch yoke shown in FIG. 2. FIG. 3 is a cross-sectional view of a reinforced scotch yoke shown in FIG. 2. It is a force diagram which shows the force relationship which acts between the scotch yoke by this invention, and a transmission block. It is a fragmentary sectional view of other embodiments using a ram type piston as an actuator of the Scotch yoke type actuator by the present invention. It is a fragmentary sectional view of a scotch yoke type actuator according to a conventional embodiment. It is explanatory drawing for obtaining an output torque from the action | operation of the scotch yoke and transmission block of the scotch yoke type actuator in embodiment by this invention.

  Embodiments of the present invention will be described below with reference to FIGS. 1 to 7 and FIG. In addition, what has the same reference number as FIG. 8 demonstrates as what shows the substantially same structural member.

  An embodiment of the present invention will be described with reference to FIG. 1. A Scotch yoke type valve operating device is provided inside a casing 9 provided so that a valve stem 1 of a valve such as a pipeline is located inside. A scotch yoke 2 for rotating the valve stem 1 is provided so as to be swingable about the axis of the valve stem 1. The scotch yoke 2 has end portions by nuts on pistons 71 and 81 such as cylinders 72 and 82 and pistons 71 and 81 constituting the actuator 8 of one actuator 7 on the valve opening side and the other actuator 8 on the valve closing side. The transmission block 4 which is fitted and fixed by the pin 52 is attached to the rod 5 which is fixed. As shown in FIG. 3, the transmission block 4 has guide rods 6 attached to the casing 9 with both ends fixed to the casing 9 in parallel with the rod 5 on the remote side from the valve stem 1 to slide the transmission block 4. A fitting hole 44 for fitting so as to be movably supported is formed to stabilize the operation of the transmission block 4 and to reinforce the structure, in particular, the bending strength of the rod 5 by the guide rod 6. Has been.

  As shown in FIG. 2, the scotch yoke 2 includes a scotch yoke boss 24 integrated so that the valve stem is integrally rotated by the key 14, and a valve stem fitting of the scotch yoke boss 24 having a predetermined required length. A shaft hole 12 is formed, and an arm 25 having a predetermined length protruding in the same radial direction from the outer peripheral portion thereof is provided so as to be sandwiched also on the opposite side of the transmission block 4. The transmission block 4 shown in FIG. 3 includes a pair of pressing portions 41 having substantially semicircular cross sections at both corners remote from the rod 5 on both sides facing the arms 25, 25. 41 is provided so that even if the arm 25 of the scotch yoke 2 swings, the contact can be obtained smoothly. The pressing portions 41, 41 are provided so as to receive the arm 25 on the other side also on the back surface side in FIG.

The Scotch yoke type operating device having the above-described configuration operates as follows when a valve provided in a pipeline or the like is opened or closed. In the following description, it is assumed that one actuator 7 operates when the valve is opened and the other actuator 8 operates when the valve is closed.
When the valve is opened, pressurized air is supplied between the piston 71 in the cylinder 71 and the lid 73 for closing the cylinder 71 from the air inlet / outlet 731 of one actuator 7, and the piston 71 is pushed to show the dotted line together with the rod 5. When the piston is moved to the position of the piston, the scotch yoke 2 is swung from the position indicated by the solid line to the position indicated by the two-dot chain line in FIG. At that time, since the transmission block 4 is integrated with the rod 5 and the pin 52, it slides on the guide rod 6 with the movement of the rod 5, and between the pressing portions 41, 41 of the transmission block 4 in FIG. The arm 25 of the scotch yoke 2 that is in contact with the right pressing portion 41 is pressed by the pressing portion 41 while moving leftward, and the rod 5 moves leftward to start swinging leftward about the center of the valve stem. The valve can be opened by swinging to the position of the two-dot chain line of the scotch yoke 2 and rotating the valve stem.

  When the other actuator 8 is operated, the pressure air supplied between the lid 83 and the piston 81 from the air inlet / outlet 823 provided in the lid 83 that closes the end of the cylinder 82 is the same as the one actuator 7. As a result, the piston 81 is moved rightward and the rod 5 fixed integrally with the piston 81 is moved rightward to move the transmission block 4 from the position of the two-dot chain line to the position of the solid line. The arm 25 of the scotch yoke 2 that is pressed in contact with the pressing portion 41 swings, and the valve stem 1 can be rotated to close the valve.

The advantages of the above Scotch yoke type actuator will be described as follows. Prior to that, a conventional scotch yoke actuator will be described with reference to the force diagram of FIG. As a premise, assuming that the distance from the valve stem axis to the center of the rod 5 is H and the distance from the center of the rod to the guide rod 6 is H, the distance from the valve stem center to the guide rod 6 is 2H. The force F generated from the pistons 71 and 81 and transmitted to the rod 5 is transmitted only to the rod 5, and the scotch yoke 2 is swung only by the force F of the rod 5. Accordingly, the torque applied to the stem shaft is T = R · W, where R ₁ = F / cos θ and H = W / cos θ, as shown in FIG. 6, T = FH / cos ² 45 ° , Θ = 45 °, T = 2FHη (η = efficiency), and the guide rod 6 parallel to the transmission block 4 and the rod 5 is only a support for strength such as bending of the rod 5, and the torque is increased. Absent. In the present invention, since the transmission block 4 is strong, the same F force is also transmitted to the pressing portions 41 and 41 of the transmission block 4 at substantially the same position as the guide bar 6. 6 can generate a higher output than that of FIG. Further, the set of the fully open or fully closed position can be received in a straight line from the conventional rotation, and there is an advantage that an unreasonable force such as bending is not applied to the set bolts 92, 93, etc.

  Further, when the output torque of the scotch yoke 2 in the scotch yoke type actuator according to the present invention is calculated, it can be explained by the operation diagram shown in FIG. The force of F at the center of the rod 5 is transmitted to the entire transmission block 4 indicated by a rectangular cross line in the center. Therefore, assuming that the distance between the valve stem, the rod 5 and the center of the guide rod 6 is H and the inclination of the scotch yoke 2 at that time is θ, the relationship between the positions is shown in the explanatory diagram of FIG. The relationship is as shown. The output torque T obtained therefrom is obtained by the following equation.

That is, T = 2l·L where 2l = F / cos θ and L = 2H / cos θ.
T = F · 2H / cos ² 45 where θ = 45 °,
T = F · 2H / cos ² 45 = 2 · F · 2H = 4FH.
Note that the output torque obtained with the conventional apparatus is T = 2FH.

  In the scotch yoke type actuator according to the present invention, the transmission block 4 further includes the arm 25 of the scotch yoke 2 that extends from the center of the valve stem to a remote position. Because of this structure, it extends to the outside which is farther from the guide rod 6. This length is indicated by P in FIG. 1, and if the width of the arm 25 is also used, the center of the arm 25 of the scotch yoke 2 becomes the side surface in the width direction of the arm 25. Even if the angles are the same, since the contact surfaces of the scotch yoke 2 arm 25 and the pressing portions 41 and 41 become large, a higher output torque can be obtained.

In this case, the output torque T when the arm 25 of the scotch yoke 2 is inclined by 5 ° is as follows.
That is, T = WL where WL = (2l + P) L = F / cos θ and L = 2H / cos θ.
T = F2H / cos ² θ where θ ² = 50 ° = 2.42
T = 4.84FH
It becomes.

Here, when comparing the amount of air consumption required for the rotation of the valve stem of the conventional Scotch-Yoke type actuator and the device of the present invention, it is the same as described below. This is because even if the piston and rod dimensions are the same and the output torque is increased, the operation amounts of the piston and rod are the same.
Air consumption = (π / 4) D ² + π / 4 (D2−d2) XL
Here, D = diameter of the cylinder, d = diameter of the rod, and L = the length by which the valve stem rotates 90 °.
However, according to the present invention, the force relating to the torque is applied by pressing the transmission block 4 and the guide bar 6 through the transmission block 4 on both sides of the transmission block 4 having substantially the same diameter as the fitting bar and the fitting hole 44. The arms 25 of the scotch yoke 2 are rotated by the portions 41 and 42. However, since the stroke of the rod 5 on which the fluid pressure acts is the same as that of the conventional one, the feature is that the air consumption does not change.

In the above embodiment, the force transmitted to the rod 5 by the pressure air (which may be N ₂ gas or the like) received by the cylinders 72 and 82 is not transmitted to the scotch yoke 2 but is connected to the pin 52. Since it is transmitted to the transmission block 4 and both sides of the arm 25 of the scotch yoke 2 provided between the pressing portions 41 and 41 of the transmission block 4 are pushed when the valve is opened and when the valve is closed, the scotch yoke 2 is pushed by this force. When the section coefficient of the scotch yoke 2 is insufficient, FIG. 4 which is a perspective view of the end portion of the scotch yoke 2 and FIG. 5 which is a sectional view of an intermediate portion of the arms 25 and 25 are shown. Thus, you may provide the integral reinforcement part which does not contact | abut to the pressing parts 41 and 41 of the transmission block 4. FIG.

  Further, not only the Scotch yoke type actuator using the actuator using the piston and rod according to the above embodiment, but also the rod 5 is moved using the ram type piston 100 as shown in FIG. 7 as the actuator. It may be.

  In the above embodiment, details are not explained and illustrated, but it is natural that bearings for supporting the rotation of the rod, O-rings for sealing, and the like are used where necessary.

  Furthermore, the intervals between the valve stem, the rod, and the guide rod in the explanatory diagram of the output torque as shown in FIG. 9 can be freely changed. By changing these intervals, the output torque can be changed. It is also possible to change. The actuators 7 and 8 are described with the right actuator 7 in FIG. 1 as the valve opening side and the left actuator 8 as the valve closing side. Conversely, the left actuator is the valve opening side and the right actuator is the valve opening side. It may be used as the closed side.

  Further, the actuator may be provided only on one side of the casing, and the rod that operates the transmission block may be slid by supplying and exhausting pressurized air on both sides of the piston.

  As described above, it is obvious that the Scotch yoke type valve actuator according to the present invention is not limited to the above-described embodiment, and can be implemented within the technical scope described in the claims.

DESCRIPTION OF SYMBOLS 1 Valve stem 2 Scotch yoke 3 Transmission pin 4 Transmission block 5 Rod 6 Guide rod 7 One actuator 8 The other actuator 9 Casing 10 Connecting pipe 12 Valve stem fitting shaft hole 14 Valve stem key 22 Long hole 24 Scotch yoke boss 25 Arm 26 Reinforcing part 41 Pushing part 42 Stopper 44 Guide rod fitting hole 46 Pin hole 48 Stopper 52 Fixed pin 71 Open side piston 72 Open side cylinder 74 Tie set bolt nut 81 Closed side piston 82 Closed side cylinder 94 Bolt 95 Top cover 100 Ram type Piston 712 O-ring 731 Open side air inlet / outlet 823 Closed side air inlet / outlet

Claims (6)

A scotch yoke type actuator that opens and closes a valve by rotating a stem of a valve provided in a pipeline or the like,
A casing for housing the main part of the actuator,
A scotch yoke that swings about the valve stem so that an end of the valve stem is fixed to open and close the valve stem;
A transmission block that is slidably supported to oscillate the scotch yoke, and has a pressing portion provided oppositely in contact with the vicinity of the other end of the scotch yoke;
Both ends of the casing are fixed to a guide rod for slidably supporting the transmission block. The guide rod is fixed to the transmission block and slidably moves along the guide rod. An actuator comprising a rod, a piston in a cylinder provided on at least one side wall of the casing, and an end of the rod being fixed and operating by fluid pressure, a ram rod, and the like;
Including scotch yoke actuator.   A guide rod for guiding the transmission block is disposed on the remote side of the rocking radius of the scotch yoke and is positioned and fixed to the casing. The rod is fitted and fixed to the transmission block, and a side wall of the casing. The scotch-yoke type actuating device according to claim 1, wherein the scotch-yoke type actuating device is slidably supported.   The actuator is provided on both side walls of the casing, and one of the actuators can act as an actuator for opening the valve, and the other of the actuators can be used for closing the valve. The scotch yoke type actuator according to claim 1.   2. The scotch yoke according to claim 1, wherein the actuator of the scotch yoke type actuator is provided on one side wall and operates by supplying and exhausting air by switching fluid pressure to both sides of the piston of the actuator. Actuator.   The set bolt is provided so as to project inside the side wall of the casing, and the set bolt is provided so as to avoid a collision with the side wall of the transmission block and set the position. The scotch yoke actuator described.   The scotch yoke is provided so as to be sandwiched between the pressing portions of the transmission block, and a reinforcing portion wider than the width of the portion where the pressing portion is sandwiched is integrally provided in the scotch yoke for reinforcing the strength. The scotch yoke type actuator according to claim 1, wherein

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