DE2508683A1 - Shut-off valve drive - has two cylindrical housings and three pistons with separating shaft - Google Patents

Abstract

The shut-off valve drive comprises two pistons (5, 7) separated from each other to run in opposite directions. The separting shaft (2) is so arranged in the cylinder housing (1) that it cuts the housing axis. The shaft (2) has two opposed lever arms (3) which are coupled to the pistons via intermediate links (4, 6). A second cylinder housing (11) with a third piston (18) is installed at one end of first cylinder housing on the same axis. The piston surface facing the shaft (2) can be operated upon by a pressure medium, while the opposite surface is operated upon by a pressure spring (23). The piston rod (12) extends within the bordering section of the first cylinder housing (1).

Description

12-6 Minami Aoyama 4 ~ Chome,

Minato-Ku, Tokyo

JAPAN

Drive for shut-off devices

The invention relates to a drive for shut-off devices with closure parts which can be rotated or pivoted about an axis with a cylinder housing in which two pistons are arranged axially displaceably coaxially, with a transverse to the direction of movement of the pistons, rotatably mounted output shaft and with a geared one Connection between the piston and the output shaft.

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In known drives of the type mentioned, for example as rotary drives for flap valves Are used, the two pistons are firmly connected to one another via an intermediate piece. The pistons will alternately acted upon. The output shaft is at a distance from the axis of the piston outside of the piston Trajectory. A pin-and-slot connection between the connecting part is used as a geared connection the two pistons and the output shaft are provided.

Drives of this type have a relatively large volume.

The object of the invention is to create a drive of the type mentioned which can be manufactured in a compact design is and are provided with the means with which the failure of the pressure supply system for the drive Assumption of a predetermined end position is ensured, preferably the closed position of the shut-off element.

This object is achieved according to the invention in that the pistons are designed to be separately movable and movable in opposite directions are that the drive shaft is arranged in the cylinder housing that it intersects the housing axis that the output shaft is further provided with two oppositely directed lever arms, which are connected via intermediate links are drivingly connected to the piston that at one end of the cylinder housing a second with the first coaxial cylinder housing is arranged with a third piston on its facing the output shaft A pressure medium can be applied to the surface,

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while a compression spring acts on its opposite surface, and its piston rod engages in the adjacent Cylinder of the first cylinder housing extends and connected at its end to the adjacent piston is, and that the / Lritte piston continues with a through the opposite cover of the second cylinder housing extending rod is provided on which a Operating handle is arranged.

Preferably, as a connection between the piston rod of the third piston and the adjacent piston in the first cylinder housing in the end face of this piston a blind hole undercut with an annular groove and in the end of the piston rod of the third piston a screw with a multiple radially slotted hollow End portion provided, the slotted portion at its end with an engaging in the annular groove Outer flange is provided.

The handle is preferably connected to the rod arranged on the 3 · piston via a thread.

The invention is illustrated in the drawing in one embodiment and in the following in detail described with reference to the drawing.

Fig. 1 shows a side view of an inventive Drive.

Fig. 2 shows a section along the line II-II in Fig. 1.

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Fig. 3 shows, on a larger scale, a detail of a connection.

Fig. 4 shows a section along the line IV-IV in Fig. 3.

Fig. 5 shows a perspective view of a plate spring.

The drive shown in the drawing has a housing 1 provided with a cylinder bore, in the center of which an output shaft 2 is rotatably mounted transversely to the cylinder axis, which is provided at its outer ends with a torque-transmitting form shoulder. On both sides of the output shaft 2, a piston 5 or 7 is arranged in the cylinder, each of which is sealed against the cylinder wall ^{by means of seals 5 1} and 7 ^{1 on its circumference.}

A double-armed lever 3 is arranged fixedly in terms of rotation on the output shaft 2. The end of one lever arm is connected to the piston 5 via an intermediate link M- , while the end of the other lever arm is connected to the piston 7 via an intermediate link 6. The output shaft is connected to the piston via the intermediate links 4 and 6 in such a way that an axial movement of the piston produces a rotary movement of the output shaft. The housing is at the ends with connections 9 and 10 for

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provided a print medium. Another connection 8 is located in the middle of the case. Compressed air is preferably used as the pressure medium.

On one cylinder cover of the housing 1 there is a further cylinder housing 11 which is screwed with a threaded projection in the piston head 11 ″ into a corresponding bore in the adjacent cylinder cover of the housing 1. On the opposite side, the cylinder 11 is closed by a cylinder cover 11 A third piston 18, which has a sealing ring 18 'on its circumference, is axially displaceable in the cylinder 11. The third piston 18 is screwed onto and firmly connected to a piston rod 12. The piston rod 12 is passed through the cylinder base 11' in a sealed manner and connected at its end to the piston 7. This connection is shown on an enlarged scale in Fig. 3. Starting from the free end of the piston rod 12, the latter is provided with a blind bore 13 which merges into a thread 13 'at its inner end Connecting element is a hollow screw 14- is provided with a threaded end in the Ge winch 13 ^{1 can be} screwed in. A mushroom-shaped head with a circumferential flange is provided at the opposite end. Starting from this end, the screw 14 is provided in a cross shape with 4 slots which allow the flange sections of the screw head to spring inward.

In the bottom of the piston 7 a blind hole is provided, which is connected at its bottom with a circumferential annular groove 16

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ropes is. ^ ^As outer end of the blind bore is provided with a rounded shoulder 16 x.

For assembly, it is sufficient to press the head of the screw 14 against the rounded edge 16 '. The through the Resilient tongues formed by incisions are then pushed radially inward. After the head in the The area with the undercut hat 16 has entered, the tongues spring outwards again and create the desired connection.

On the opposite side of the piston 18, a threaded rod 19 is formed which passes through a bore is passed in the cylinder cover 11 '. The threaded rod 19 is provided with a longitudinal groove, in which engages a wedge 22 which is fixed in a corresponding groove in the bore of the cylinder cover 11 '. The threaded rod 19 extends over the cylinder cover 11 'to the outside. On its outboard end is a handwheel 20 provided with an internal thread is screwed on.

Between the piston 18 and the cylinder cover 11 'is a package of disc springs 23 arranged through which the Piston 18 is biased towards housing 1.

The cylinder 11 is provided adjacent to the cylinder ^{cover 11 11} with a connection 24 for the pressure medium.

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The described drive can with its around the outlets the output shaft 2 formed flanges are attached directly to a valve housing.

In Fig. 2, the drive is shown in its one end position, for example the closed position of the shut-off device can be. In order to operate the valve, pressure medium is fed into the cylinder 11 via the connection 24 introduced. As a result, the piston 18 is moved to the left against the action of the springs 23. About the piston rod 12, the piston 7 is moved along with it j while the piston v 5 is moved to the right via the geared connection between the pistons 5 and 7. In addition, in the space between the pistons via the connection 8 pressure medium are supplied. About the handwheel 20 can set the end position of the output shaft 2 and thus the position of the closure part of the shut-off device.

If the closure element of the shut-off element is to be moved in the opposite direction, for example from the open position into the closed position, is over the connections 9 and 10 are supplied with pressure medium by means of which the two pistons 5 and 7 are moved against one another. At the same time, the connections 8 and 24 - with a pressure medium outlet in the case of compressed air with the ambient air tied together. The movement in this direction is supported by the disc springs 23

If the pressure medium fails during operation and connections 8, 9, 10 and 24 are all depressurized are, the drive is in the

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In Fig. 2 shown end position returned, so for example the valve automatically closed.

Using the handwheel 20, it is possible to operate the drive in the opposite direction in the event of a failure of the pressure medium To move direction against the action of the disc springs 23, so, for example, to open the shut-off device. The adjustment movement of the handwheel 20 is thereby over the screw 17 on the piston 7 and thus on the output shaft 2 transferred.

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Claims (2)

Claims ί 1.) Drive for shut-off devices with rotating around an axis - or pivotable closure parts with a cylinder housing in which two pistons can be axially displaced on the same axis are arranged, with a rotatably mounted output shaft lying transversely to the direction of movement of the pistons and a geared connection between the piston and the output shaft, characterized in that that the pistons (5, 7) are designed to be separate and movable in opposite directions, .that the output shaft (2) in the cylinder housing (1) Is arranged so that it intersects the housing axis that the output shaft with two opposite directed lever arms (3) is provided, which are connected to the piston via intermediate links (4-, 6) that on one side of the cylinder housing a second with the first coaxial cylinder housing (11) with a third piston (18) is arranged on its the A pressure medium can be applied to the surface facing the output shaft, while on its opposite * A compression spring (23) acts and its piston rod (12) moves into the adjacent cylinder section of the first Cylinder housing extends and is connected at its end to the adjacent piston (7), and that the piston further with one extending through the opposite cylinder cover (11 ') of the second cylinder housing Rod (19) is provided, on the outer end of which an actuating handle (20) is arranged. 609837/0491 - ίο - 2. Drive according to claim 1, characterized in that as a connection between the piston rod (12) of the third piston (18) and the adjacent piston (7) in the first cylinder housing (1) in the end face this piston has a blind hole undercut with an annular groove (16) and in the end of the piston rod (12) a screw (14) ″ with a hollow end section with multiple radial slits is provided is, wherein the slotted section at its end with an outer flange engaging in the annular groove (15) is provided. 3 · Drive according to claim 1, characterized in, that the rod extending through the cylinder cover (11 ') of the second cylinder housing (11) (19) is guided non-rotatably in the cover and the handle (20) is connected to the rod via a thread is. 609837/0491 Blank page