GB2073815A

GB2073815A - A Door Actuating Mechanism

Info

Publication number: GB2073815A
Application number: GB8111269A
Authority: GB
Original assignee: IFE GmbH
Current assignee: IFE GmbH
Priority date: 1980-04-11
Filing date: 1981-04-09
Publication date: 1981-10-21
Also published as: DE3114255A1; AT378030B; FR2480345A1; ATA197580A; FR2480345B3; FI811118L; GB2073815B

Abstract

A fluid pressure operated actuating device for opening and closing a door comprises a double- acting piston 5 and cylinder 4 arrangement. The door is moved by a driven rotary spindle 16 and a screw transmission in the form of rollers 8, 9 operating in inclined slots 15, 10 in inner and outer tubes 12, 11 respectively converts linear movement of the piston into rotary movement of the spindle. The screw transmission is self-locking and in end position. Pusher means move the screw transmission out of the end position on failure of the piston and cylinder arrangement. In the end closure region, a piston rod 6 pushes against a spring plate 19 and as soon as the pressure of the working fluid under the piston 5 is relieved a compression spring 18 moves the piston rod 6 with a yoke 7 downwardly. <IMAGE>

Description

SPECIFICATION A Door Actuating Mechanism This invention relates to a door actuating mechanism.

It has previously proposed to provide a fluid pressure operated actuating mechanism for opening and closing doors, in which linear movement of a double-acting piston is converted by means of a screw transmission into a rotary movement and the screw transmission is adapted to be self-locking in the closure end region.

A mechanism of this kind is described in German Offenlegungsschrift 25 38 529. 1 Here all the actuating elements are accommodated in a tube at the end of which are arranged swing arms for actuating the doors. The piston has a piston rod whereof the free end is provided with a yoke which is provided at both sides of the piston rod with a respective roller pair. The rollers cooperate with slots in tubes which surround the piston rod.

A stationary tube has axially extending slots and a movable tube provided with the swing arms has inclined slots. The stationary slots guide the yoke on displacement of the piston and prevent it from rotating. The inclined slots cause pivoting of the tube with the swing arms. In their end region the inclined slots extend axially so that in this region the roller pairs bring about a self-locking action.

The disadvantage of this embodiment is that release is only possible by means of an oppositely directed movement of the piston. If the pressure source for the drive medium should fail the selflocking feature prevents opening of the doors by hand.

An object of the invention is to overcome this disadvantage and this is achieved by virtue of the fact the piston in its closed end position is disposed in the range of movement of a slider which is manually actuatable and/or is under the influence of an energy store which is loaded by the piston in the course of the closure end movement.

The invention will now be further described by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a part longitudinally sectioned elevation of one embodiment of actuating device according to the invention; Figs. 2 and 3 show the development of two coaxially arranged tubes in the region of their slots, and Fig. 4 is a part longitudinally sectioned elevation of a modified embodiment.

A housing comprising a floor 1, cylindrical casing 2 and cover 3 accommodates an eccentrically arrange work cylinder 4 with a piston 5 of which both sides can be subject to fluid pressure. Supply and discharge lines for the working fluid are not shown for the sake of clarity.

The piston 5 is provided with a piston rod 6 which extends out of the work cylinder 4 and carries a yoke 7. On this are mounted at both sides respective pairs of indeqendently rotatably rollers 8, 9. The outer roller 9 engages a slot 10 of an outer tube 11 which is fixedly arranged in the housing. Inside this tube 11 is rotatably mounted a further tube 12 by means of roller bearings 13, 14. The roller 8 engages in a slot 1 5 of this inner tube 12 which is welded to a work spindle 16 which projects from the housing.

The work spindle 1 6 has a stepped bore 17 in which is arranged an energy store in the form of a compression spring 1 8 which is supported on the one hand on the shoulder of the stepped bore 17 and on the other hand on a slider 19 constructed as a spring plate and held by means of a screw 20.

Fig. 2 shows the inner tube 12 in development so that the course of the slots 1 5 can be appreciated. In their end region 21 the slots extend in the axial direction of the tube.

Fig. 3 which shows the outer tube 11 in development indicates that the slots 10 are inclined in the opposite direction to the slots 1 5 but also extend in the axial direction in the end region 22.

If the piston is moved upwards the tube 11 with its slots 10 guides the rollers 9 and causes pivoting of the yoke 7. Additionally, because the rollers 8 follow the slots 1 5 a rotary movement is imparted to the inner tube 12 and transmitted to the drive spindle 1 6. In the upper closure region the slots 10 and 1 5 extend in the same direction so that the tubes are immobilised with respect to each other.

In the end closure region the piston rod 6 pushes against the spring plate 1 9 and stresses the compression spring 18. As soon as the pressure of the working fluid under the piston 5 is relieved the compression spring 1 8 relaxes and moves the piston rod 6 with the yoke 7 downwards by way of the spring plate 19. Thus the rollers 8, 9 move out of the end regions 21, 22 of the slots 15 and 10 so that the door connected to the spindle 16 can be opened by hand. Instead of the compression spring a rubber buffer or a gas cushion may be used as the energy store.

Fig. 4 illustrates another embodiment of the actuating device according to the invention. In place of an energy store there is provided a directly or indirectly manually operable rod 23 which holds the slider 1 9 in its uppermost position. If the pressure of the working fluid under the piston 5 is relieved when the door is closed the slider 1 9 is displaced downwardly by hand by means of the rod 23, entrains the piston rod 6 and the piston 5 and guides the rollers 8, 9 out of the self-locking region 21, 22 of the slots 1 5 and 10 so that the door can now be opened by hand.

The rod 23 passes through and projects from the upper end of a rotary post (not shown) which is seated on the spindle 1 6 and carries the door leaf. The projecting end may be provided with a handle and/or with a Bowden wire which leads to a handle which is externally accessible so that the slider 19 can also be displaced when the device is inactivated and the door can be opened.

Other devices may be provided for moving the slider 1 9. Preferably a coil spring is provided which holds the rod 23 and the slide 19 in its uppermost position so that the displacement takes place against the force of this spring.

Claims

1. A fluid pressure operated actuating device for opening and closing a door, comprising a double-acting piston and cylinder arrangement, a driven rotary spindle for moving the door, a screw transmission for converting linear movement of the piston into rotary movement of the spindle, the screw transmission being self-locking in an end position thereof, and pusher means for moving the screw transmission out of said end position on failure of the piston and cylinder arrangement.

2. A device as claimed in claim 1, wherein the pusher means projects into that section of the path of movement of a component connected to the piston corresponding to the closure end region of the screw transmission.

3. A device as claimed in claim 1 or 2, wherein the pusher means is arranged within a rotatably mounted tube driven by the screw transmission in the movement end region of a piston rod projecting from the work cylinder and guided coaxially with respect to the tube, whereby the free end of the piston rod cooperating with the pusher means is provided with a yoke carrying at its ends respective roller pairs engaging in slots of the rotatably mounted tube and of a stationary outer tube surrounding the rotatable tube, and at least the slots of one of the two tubes extending helically and having in the closure end region the same or approximately the same course as the slots of the other tube so as to lock the tubes against relative movement in this region.

4. A device as claimed in claim 3, wherein the slots of both tubes extend helically but with the opposite hand.

5. A device as claimed in any one of claims 1 to 4, wherein the pusher means is connected with a rod passing through and projecting from the upper end of a rotary door post, which rod is displaceable axially against the piston by means of a handle or the like.

6. A device as claimed in any one of claims 1 to 4, wherein a compression spring, an elastomeric buffer, a gas cushion or other means is provided as an energy store for assisting movement of the pusher means, said energy store being loaded by the final closing movement of the screw transmission.

7. A fluid pressure operated actuating device for opening and closing a door, substantially as herein described with reference to and as illustrated in Figs. 1 to 3 or Fig. 4 of the accompanying drawings.