JP7186993B2 - Valve actuators and diaphragm valves - Google Patents

Description

The present invention relates to a valve drive device and a diaphragm valve.

As a conventional diaphragm valve, for example, one disclosed in Patent Document 1 is known. This diaphragm valve is a manual valve, and includes a valve body that defines a flow path, a diaphragm that is movably provided with respect to a valve seat formed in the valve body and opens and closes the flow path, a diaphragm presser that presses the diaphragm, and a drive mechanism for driving the diaphragm presser in the opening/closing direction. The drive mechanism is housed in a casing provided on the valve body, and includes a stem rotatably held in the casing and a cam groove guided movably in the valve opening/closing direction while the rotation is restricted within the casing. A cam pin provided on the stem is engaged with a cam groove of the cam cylinder via a roller, so that the stem can be rotated by using a handle. The cam cylinder moves in the opening direction or in the closing direction according to the rotation direction of the diaphragm to operate the diaphragm.
Also, in order to maintain the rotational position of the cam cylinder at the open and closed positions, a ball and a spring are provided in the ball receiving hole formed in the stem, and the entrance of the ball receiving hole is crimped so that the ball partially protrudes. When the ball is fully opened, the ball is brought into contact with the end of the cam groove on the fully closed side, or when the ball is fully closed, the ball is brought into contact with the end of the cam groove on the fully open side. Force restricts the rotation of the stem to stably hold the diaphragm valve at the fully open or fully closed position.

Patent No. 3570620

In the above-mentioned diaphragm valve, an end mill is used for machining the cam groove formed by the through hole in the cam cylinder. At this time, the wall surface of the cam groove is machined by side cutting with an end mill, but the machined shape does not come into uniform contact with the guide roller. become. In the current design, the contact between the groove shape and the roller is in a linear or irregular shape, and there is a problem that the motion of the roller moving in the cam groove is not smooth. In addition, when the diaphragm valve is fully closed, it is necessary to press the diaphragm against the main body with a constant force, and a structure that maintains the holding force and pressing force is required.
In addition, in the above diaphragm valve, it is necessary to form a ball accommodation hole in the stem, accommodate the spring and the ball in this accommodation hole, and caulk the entrance of the accommodation hole. There is also the problem of high prices.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a valve drive device that provides smoother movement and reduces manufacturing costs.

A valve driving device according to the present invention is a valve driving device for driving an operation member for operating a diaphragm of a diaphragm valve in an opening/closing direction,
a stem that is rotatably held about a predetermined axis and has a groove including a cam groove on its outer peripheral surface;
a movable member connected to the operating member, restricted from rotating about the predetermined axis, and guided so as to advance and retreat in the direction of the predetermined axis;
and a ball held by a holding recess formed in the movable member and a groove of the stem, and moving in the groove as the stem rotates.

Preferably, the groove portion has a lock groove that is formed continuously with the cam groove at both ends of the cam groove and that locks the rotational position of the stem in a releasable manner. More preferably, a configuration can be adopted in which the depth of the cam groove and the depth of the lock groove correspond to each other.

A diaphragm valve according to the present invention includes the valve driving device having the above configuration.

According to the present invention, by adopting the configuration in which the cam groove is formed in the stem, it becomes possible to more easily machine the cam groove whose shape accuracy is ensured. In particular, by machining the cam grooves on the stem using a ball end mill, machining time can be greatly reduced while ensuring machining accuracy.
In addition, according to the present invention, the lock groove is formed integrally with the cam groove, and the ball is engaged with the lock groove to lock the rotation of the stem releasably at the fully open position or the fully closed position. It can be simplified.
According to the present invention, without using an elastic member such as a spring, the rotation of the stem can be releasably locked by the lock groove formed continuously with the cam groove, so that the structure can be simplified and the cost of the device can be reduced. becomes possible.
Furthermore, according to the present invention, since the groove of the stem exerts a cam action and a locking action on the movable member through the interposition of the balls, opening and closing operations of the diaphragm valve are very smooth.

1 is a longitudinal sectional view of a diaphragm valve according to an embodiment of the present invention, showing a valve fully open state; FIG. 2 is an exploded perspective view of the drive device of FIG. 1; FIG. Fig. 10 is a front view of the drive device with the parts other than the stem indicated by dotted lines, showing a state in which the valve is fully open; FIG. 2B is a front view of the drive device of FIG. 1, showing a state in which the valve is fully closed by rotating the stem 90 degrees from the state of FIG. 2B; FIG. 4 is a developed view of a groove including cam grooves and lock grooves; FIG. 3B is a cross-sectional view of the cam groove taken along line 3B-3B of FIG. 3A; FIG. 4 is a top view showing the relationship between balls and grooves; FIG. 2 is a vertical cross-sectional view of the diaphragm valve of FIG. 1, showing the valve fully closed state; The top view which shows the modification of a groove part.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a diaphragm valve 1 according to one embodiment of the invention. The diaphragm valve 1 includes a valve body 2 defining a flow path 2a, a diaphragm 5 made of flexible metal, resin, or a combination thereof, a casing 7, a cap 8, a diaphragm presser 9, an adjusting screw 10, and a handle 20. and a valve drive device 30 .
The valve body 2 has an opening 3 at its upper portion and a valve seat 4 formed near the opening 3 .
A diaphragm 5 is fixed between the valve body 2 and the casing 7 so as to close the opening 3 .
The casing 7 is fixed to the valve body 2. A cap 8 is screwed and fixed to the outer circumference of the upper end of the casing 7, and the diaphragm retainer 9 and the valve driving device 30 connected thereto are accommodated therein. . A space between the casing 7 and the cap 8 is sealed with an O-ring OR. A cylindrical adjusting screw 10 is screwed into the opening of the upper end of the casing 7, and the position of the valve driving device 30 in the vertical direction A1, A2 can be adjusted by this adjusting screw. That is, the movable range of the diaphragm presser 9 is adjusted by the adjustment screw 10 .
A stem 40 of the valve drive device 30 passes through the adjusting screw 10 , and a C-shaped retaining ring 11 is mounted on the stem 40 above the adjusting screw 10 . It is held by the upper end surface of the adjusting screw 10 . Thereby, the stem 40 is held by the casing so as to be rotatable around the central axis Ct.
An O-ring OR is mounted above the C-shaped retaining ring 11 of the stem 40 , and the O-ring seals between the cap 8 and the stem 40 .
A handle is attached to the upper end of the stem 40, and the stem 40 can be rotated by rotating the handle 20 about the central axis Ct.

FIG. 2A shows an exploded perspective view of the driving device 30. As shown in FIG.
The driving device 30 has a stem 40 , a movable member 50 , a steel ball 60 , a cylindrical pin 70 and a guide pin 90 .
A groove portion 41 is formed on the outer peripheral surface 40a of the stem 40 so that a ball 60 made of a steel ball or the like can be engaged. The grooves 41 are formed at two rotationally symmetrical locations on the outer peripheral surface 40 a of the stem 40 .

3A to 3C show the structure of the groove portion 41. FIG. The groove portion 41 includes a cam groove 42 , an upper lock groove 43 formed continuously from the upper end of the cam groove 42 , and a lower lock groove 44 formed continuously from the lower end of the cam groove 42 .
As shown in FIG. 3B, the cam groove 42 has a semicircular cross section with a radius R1. In addition, the cross section of the cam groove 42 can be formed in an arcuate shape shallower than that in FIG. 3B.
As shown in FIG. 3C, the upper lock groove 43 and the lower lock groove 44 are formed to have the same depth as the cam groove 42, and have a semicircular cross section with a radius R1. As can be seen from FIG. 3A, the upper lock groove 43 is formed in a direction inclined downward by 5 degrees with respect to the horizontal direction, and the lower lock groove 44 is formed in a direction inclined upward by 5 degrees with respect to the horizontal direction. formed.
The cam groove 42 slopes upward from the lower lock groove 44 toward the upper lock groove 43, while the upper lock groove 43 slopes downward. By reversing the formation directions of the cam groove 42 and the upper lock groove 43 , the ball 60 moving in the cam groove 42 from the lower lock groove 44 side toward the upper lock groove 43 side reaches the upper lock groove 43 . Then, the upper locking groove 43 is releasably locked by the inclination of 5 degrees. Similarly, by reversing the formation directions of the cam groove 42 and the lower lock groove 44, the ball 60 moving in the cam groove 42 from the upper lock groove 43 side toward the lower lock groove 44 side moves toward the lower lock groove 44 side. When it reaches the lock groove 44, it is releasably locked by the inclination of the lower lock groove 44 at 5 degrees.
In FIG. 3A, the distance ST between the upper lock groove 43 and the lower lock groove 44 in the vertical direction A1, A2 defines the stroke of the movable member 50 in the vertical direction A1, A2, which will be described later. The horizontal distance R of 44 defines the rotation angle of stem 40 (90 degrees in this embodiment).
A ball end mill, for example, can be used as a tool for machining the cam groove 42 , the upper lock groove 43 and the lower lock groove 44 . If the radius of the R portion at the tip of the ball end mill is adjusted to match the radius R1, both the machining accuracy and the machining time can be greatly improved compared to the side cutting of the end mill.

Returning to FIG. 2A, the movable member 50 has a cylindrical portion 51 into which the outer peripheral surface 40a of the stem 40 is inserted. In the cylindrical portion 51, accommodation holes 52, which are through holes extending in the radial direction, are formed at two positions rotationally symmetrical with respect to the central axis Ct.
The accommodation hole 52 is formed with a diameter slightly larger than the diameter of the ball 60, and the accommodation hole 52 holds the ball 60 so that it can roll.
The cylindrical pin 70 is preferably made of a metal cylindrical member, has an outer shape slightly larger than the diameter of the receiving hole 52 , and is made of a softer metal than the ball 60 . This is for reducing the rotational friction of the ball 60 . The cylindrical pin 70 prevents the ball 60 that is driven (press-fitted) into the housing hole 52 from behind the ball 60 that is housed in the housing hole 52 from falling out of the housing hole 52 . The receiving hole 52 and the cylindrical pin 70 constitute a holding recess that holds the ball 60 in cooperation with the groove portion 41 . The ball 60 is held by the bottom (cylindrical pin) and inner peripheral surface of the holding recess and the groove 42 . By using the cylindrical pin 70 , a part of the ball 60 is slidably fitted to one end of the cylindrical pin 70 . The position of the cylindrical pin 70 in the receiving hole 52 is adjusted so that the ball 60 can move smoothly between the groove 41 and the holding recess and rattle is minimized.
A guide pin hole 54 penetrating the movable member 50 in the diameter direction is formed below the bottom surface of the cylindrical portion 51 of the movable member 50 . A guide pin 90 is inserted into the guide pin hole 54 , and both ends of the guide pin 90 protrude from the outer peripheral surface of the movable member 50 . By fitting the guide pin 90 into the guide grooves (not shown) formed in the casing 7 along the directions A1 and A2 of the central axis Ct, the rotation of the movable member 50 about the central axis Ct is restricted and the central axis It is guided forward and backward in the Ct directions A1 and A2.

FIG. 2B shows the valve drive device 30 when the diaphragm valve 1 is fully open, and FIG. 2C shows the valve drive device 30 when the diaphragm valve 1 is fully open.
As shown in FIG. 2B, each ball 60 is positioned in the corresponding upper lock groove 43 when the diaphragm 1 is fully open. That is, each ball 60 is housed in the housing hole 52 in a state in which a part protrudes from the housing hole 52 toward the stem 40 .

When the handle 20 (not shown) is operated to rotate the stem 40 about the center axis Ct from the state shown in FIG. Since the upper locking groove 43 and the cam groove 42 are adapted to the ball, and the ball 42 freely rolls or slides without being constrained, the handle 20 can be operated smoothly.

When the ball 60 is disengaged from the upper lock groove 43 and moved to the cam groove 42, a cam action is exerted from the cam groove 42 of the stem 40 to the movable member 50 through the interposition of the ball 40, and the movable member 50 moves downward A2. As a result, the diaphragm presser 9 presses the diaphragm 5 toward the valve seat 4 . The cam groove 42 is formed so that the ball 60 fits therein, and in addition, the ball 60 can freely roll and slide.

When the stem 40 rotates 90 degrees from the state shown in FIG. 2B, the ball 60 is fitted into the lower lock groove 44 from the cam groove 42, resulting in the state shown in FIG. 2C. In this state, the diaphragm 5 is pressed against the valve seat 4 and the diaphragm valve 1 is fully closed. FIG. 4 shows the fully closed state of the diaphragm valve 1 .
When the diaphragm 1 is fully closed, each ball 60 is positioned in the corresponding lower lock groove 44, and each ball 60 is held in the receiving hole 52 with a part protruding from the receiving hole 52 toward the stem 40 side. ing.

According to this embodiment, the cam groove 42 and the upper lock groove 43 and the lower lock groove 44 are formed in the stem 40, thereby making it easier to machine the cam groove 42 whose shape accuracy is ensured. becomes possible. In particular, by machining the cam grooves on the stem using a ball end mill, machining time can be greatly reduced while ensuring machining accuracy.
Further, according to this embodiment, the upper lock groove 43 and the lower lock groove 44 are formed integrally with the cam groove 42 , and the diaphragm valve 1 is locked by the balls 60 that engage with the upper lock groove 43 and the lower lock groove 44 . Since the rotation of the stem 40 is restricted at the fully open position or the fully closed position, the structure can be simplified.
Furthermore, according to this embodiment, since the cam groove 42 of the stem 40 exerts a cam action on the movable member 50 through the interposition of the ball 60, the cam mechanism can move very smoothly.

In the above embodiment, the cam groove 42, the upper lock groove 43 and the lower lock groove 44 are formed so as to match the radius R1 of the ball 40, but the cam groove 42 is not limited to this. , V-shaped grooves, etc., and other structures may be adopted as long as the structure of the upper lock groove 43 and the lower lock groove 44 can exhibit the function of locking the rotation.

Modification FIG. 5 shows a modification of the groove. The cam groove 42 formed in the stem 40B is similar to that of the above embodiment, but the upper lock groove 43B and the lower lock groove 44B are formed deeper than the cam groove 42. As shown in FIG. In this case, a gap is formed between the ball 60 and the upper lock groove 43B or the lower lock groove 44B. , the ball 60 can be pressed against the upper lock groove 43B and the lower lock groove 44B. Further, by forming the steps between the upper lock groove 43B and the lower lock groove 44B and the cam groove 42 into smooth inclined surfaces, smooth operation of the cam mechanism and the lock mechanism can be maintained. Also in this case, the lock mechanism only locks the rotational position of the stem by the shape of the lock groove, and does not use the biasing force of a spring or the like to lock the rotational position of the stem.

In the above-described embodiment, the stem 40 has two grooves 41, but the present invention is not limited to this. It is also possible to form

In the above embodiment, since smooth cam operation is obtained, the valve drive device of the present invention can be applied not only to manual valves but also to other automatic valves such as fluid-driven and electric valves.

1 Diaphragm valve 2 Valve body 2a Flow path 3 Opening 4 Valve seat 5 Diaphragm 7 Casing 8 Cap 9 Diaphragm holder 10 Adjusting screw 11 C-shaped retaining ring 12 Seat ring 20 Handle 30 Valve drive device 40 Stem 41 Groove 42 Cam groove 43 Upper side Lock groove 44 Lower lock groove 50 Movable member 51 Cylindrical portion 52 Accommodating hole 54 Guide pin hole 60 Ball 70 Cylindrical pin 90 Guide pin OR O-ring Ct Central axis

Claims (3)

A valve driving device for driving an operation member for operating a diaphragm of a diaphragm valve in an opening/closing direction,
a stem that is rotatably held about a predetermined axis and has a groove including a cam groove on its outer peripheral surface;
a movable member having a cylindrical portion into which the outer peripheral surface of the stem is inserted, is connected to the operating member, is restricted from rotating about the predetermined axis, and is guided forward and backward in the direction of the predetermined axis;
a ball held by a holding recess formed in the cylindrical portion of the movable member and a groove portion of the stem, and moving in the groove portion as the stem rotates;
the groove portion has a lock groove formed continuously with the cam groove at both ends of the cam groove and configured to releasably lock the rotational position of the stem;
The lock grooves are formed in a direction different from that of the groove portion and in directions inclined opposite to each other with respect to the horizontal direction,
The rotational position of the stem is releasably locked by the engagement of the ball with the lock groove, rather than by using the force of the elastic member to press the ball against the stem. ,
The holding recess is formed of a through hole that radially penetrates the cylindrical portion and accommodates the ball. consisting of a metal cylindrical pin and
valve drive. 2. The valve drive device according to claim 1, wherein said cylindrical pin is made of a material softer than said ball in order to reduce friction with said ball. A diaphragm valve comprising the valve driving device according to claim 1 or 2.

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