DE29612112U1 - Actuator for doors, in particular for vehicle doors - Google Patents

Description

Drive for doors, especially for vehicle doors

The invention relates to a drive for single or double-leaf sliding, pivoting or pocket doors, in particular vehicle doors, the drive of which comprises a rotatable spindle which is operatively connected to a freewheel, the freewheel having a rotatable drum which is connected to the spindle in a rotationally fixed manner, furthermore, in the interior of the drum, clamping bodies which are movable in the circumferential direction within predetermined limits, such as brake balls, to which a rotationally fixed wedge surface of at least one brake shoe which is fixed in the circumferential direction is assigned.

The spindle can always be rotated in the direction that corresponds to the door closing direction, but not in the other direction, the door opening direction. This measure ensures that the door can be closed manually even if the motor and/or control system fails, but that it can only be opened during normal operation (or manually after activating an emergency release, thus not accidentally or unexpectedly).

For this purpose, previously known devices provide for the part of the freewheel that participates in the blocking and does not rotate, if necessary the entire freewheel including its housing, to be mounted so that it can rotate and to be fixed with a releasable brake. As long as the brake is fixed, the freewheel works in a completely conventional way: In one direction of rotation it allows the spindle to move, in the other it blocks it. If a rotation of the spindle in the blocking direction is now desired (to open the door), the brake is released from the door control and the spindle can be rotated in the blocking direction together with the blocked freewheel.

Such a device is described in the application PCT/AT94/00146. This application has not yet been published, but devices corresponding to this application are clearly in prior use.
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These devices work satisfactorily in themselves and have proven themselves in practice. One disadvantage is the relatively high production costs, since not only a freewheel but also a suitable brake, appropriately coordinated, must be used. Another disadvantage, which is often more serious in practice, is the relatively large amount of space required by the previously known device.

Compared to the prior art, the aim of the invention is to create a device that is compactly constructed and consists of fewer parts than the previously known device.

Before the solution according to the invention is presented, the structure of a freewheel according to the state of the art will be briefly explained below: A freewheel of this type consists of a rotatable drum that is connected in a rotationally fixed manner to the spindle or the like on which the freewheel is to act. Inside the drum, clamping bodies (balls, rollers, but also non-rotationally synchro-nized clamping bodies or the like) are arranged so that they can move but cannot rotate freely, each of which is assigned a fixed wedge surface of a stationary brake shoe (possibly common to all wedge surfaces). In the following, balls are referred to as clamping bodies, but of course all types of clamping bodies can be used.

The wedge surface comprises two areas: an area in which the distance between the wedge surface and the inner wall of the drum is greater than the diameter of the clamping body and an area in which this distance is smaller. The end of the

The wedge surface with the larger distance has a nose or similar projecting radially outwards, which prevents the clamping bodies from leaving the space assigned to them. The brake shoes are arranged in a rotationally fixed manner relative to the environment (fixed by means of a brake in the case of the releasable return described above) and the balls allow the rotation of the drum in the direction in which they are pressed against the nose of the wedge surface and block the rotation in the direction in which they are carried along by the drum and pressed into the cone between the drum and the wedge surface and finally create a firm connection between the wedge surface and the inner surface of the drum shell through friction.

According to the invention, in such a freewheel, in order to achieve the objectives mentioned at the outset, it is provided that the wedge faces are radially movable and that preferably their radial adjustment is carried out by rotating a cam and the interaction of at least one pair of control surfaces between the cam and the wedge surface body.

The invention is explained in more detail below using some embodiments.
Fig. 1 is an axial section through a device according to the invention with a motor arranged coaxially to the spindle,

Fig. 2 is a section along the line II-II in Fig. 1,
Fig. 3 shows a device according to the invention between two coaxially arranged spindles,

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

Fig. 5 shows a variant of Fig. 3 with only one spindle, Fig. 6 shows a variant of Fig. 4 with a hydraulic actuation device and

Figs. 7 to 13 show the position of the individual components of the device according to the invention during the individual phases of activating or releasing the freewheel.

The structure of the device according to the invention, as can be seen in Figures 1 and 2, is as follows: A spindle 11 can be rotated in both directions by means of a motor 13. When the motor is switched off, the spindle should be blocked in the direction of arrow 14 (door opening direction), but should be freely rotatable against the direction of arrow 14.

For this purpose, a rotatable drum 1 is connected to the spindle 11 in a rotationally fixed manner. Inside the rotatable drum 1 there is a ball cage 2 that can be rotated within certain limits, in which brake bodies, for example rollers or, as in the example shown, brake balls 5, are arranged so that they can move in the circumferential direction within certain limits. Three brake bodies are preferably provided, but it is possible to use only two or even more than three such brake bodies.

The brake balls 5 are located, viewed in the radial direction, between the inner surface of the rotatable drum 1 and wedge surfaces 15 of brake shoes 3. Each brake ball 5 is assigned a (non-rotatable) brake shoe 3 with a corresponding wedge surface 15. The wedge surfaces 15 run radially (viewed in the circumferential direction) in such a way that they rise like a wedge, so that the conical space remaining between the wedge surfaces 15 and the inner drum surface has two areas.

An area in which the distance between these two components is greater than the diameter of the associated brake ball 5 and an adjacent area in which this distance is smaller than the diameter of the brake ball. Due to the constant change in this distance

This results in the brake ball being reliably clamped and the frictional engagement causing the rotating drum to be blocked when it is subjected to a torque in the blocking direction.
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According to the invention, the brake shoes 3 are arranged to be movable in the radial direction to such an extent that, in the released state of the freewheel according to the invention, the wedge surface 15 has a distance from the inner surface of the rotatable drum 1 in its entire circumferential area that is greater than the diameter of the brake ball 5.

This is achieved in the embodiment shown in that the brake shoe 3 has a radially inward-facing nose 16, which sits with play in a corresponding recess of a (non-rotatable) cover hub 4 and can be pivoted about this nose 16. The pivoting takes place through a radial movement of switching balls 6 (which maintain their position in the circumferential direction), which sit in openings in the cover hub 4 and can be displaced in the radial direction by a switching cam 10, which can be rotated to a limited extent with respect to the cover hub.

In this case, the switching cams 6 are either pressed outwards, as shown in Fig. 2, or can penetrate into recesses in the switching cam, whereby the brake shoes 3 are pivoted radially either outwards or inwards and thus fix or release the brake balls 5.

A particular advantage of the device according to the invention is that, with a drive motor for the spindle directly connected to the freewheel, as shown in Fig. 1, 3 and 5, it is possible to determine the movement of the switching cam directly from the reaction torque of the motor.

so that any additional actuating device can be omitted.

As can be seen from Fig. 3 and 5, the drive motor 13 can also be arranged offset parallel to the spindle 11, which makes it possible to install the device according to the invention in the plane of symmetry between two spindles. This is shown in Fig. 3 in an application example for the drive of a two-leaf sliding or pivoting sliding door of a vehicle. The plane of the portal center is also shown. The compactness of the device according to the invention thus makes it possible for the first time for a two-leaf vehicle door to install the drive together with the freewheel device in the middle of the portal, where accessibility for inspection and maintenance purposes is best.

When the motor 13 is installed offset from the spindle axis, the reaction torque of the motor is best transmitted via an unlocking lever 17, which is connected on the one hand to a reaction lever 18 that transmits the motor reaction torque, for example a part of the rotatably mounted motor housing, and on the other hand to the switching lever 7. Stops 19, 20 limit both the rotatability of the motor and the angle of rotation of the switching cam 10, which is connected to the switching lever 7 in a rotationally fixed manner.

In the example shown, the engine torque itself is transmitted by gears, but the use of belts etc. is of course possible.

By comparing Fig. 3 and 5, it can be seen that the device shown in these figures can be used for just one or two coaxial spindles. This device is therefore equally suitable

for use with single and double leaf doors, which dramatically reduces manufacturing and storage costs.

Fig. 6 shows a variant of the device according to the invention, analogous to Fig. 4, which can be used advantageously wherever a hydraulic or pneumatic drive is used for the door. This is particularly the case with vehicle doors, where a pneumatic piston-cylinder unit often acts on one of two door leaves and the other door leaf is moved synchronously via a symmetrically constructed double spindle.

In this case, it is advantageous to provide a freewheel according to the invention, as shown in Fig. 3 in direct connection with an electric drive, without such a drive in the middle of the double spindle and to pivot the switching lever 7 by means of a hydraulic or pneumatic piston-cylinder unit 21. For reasons of space and cost, it is preferably provided that the piston-cylinder unit 21 is designed to be single-acting and is equipped with a return spring.

The mode of operation of the device according to the invention is explained in detail below with reference to Figs. 7 to 13:

Fig. 7 shows phase 1: the freewheel is blocked, the brake shoes 3 are extended radially outwards and the brake balls 5 are pressed into the cone formed by the inner surface of the drum 1 and the wedge surface 15 of the brake shoe 3 under the action of spring-loaded pressure bolts 9, thus preventing any relative rotation between the brake shoes 3 and the drum 1 in the direction of arrow 14.

When the drum 1 is rotated against the direction of the arrow 14, the brake balls 5 are moved a little against the force of the pressure bolts 9, move from the narrow area of the cone between the brake shoes and the inner surface of the drum 1 into the wider area of the cone, the radial extent of which is greater than the diameter of the brake balls 5 and thus allow the drum 1 and thus also the component connected to it (spindle) to be rotated in the corresponding direction (against the arrow 14).

As can be seen from Fig. 7, the switching balls 6 are located on the casing areas of the switching cam 10, which are away from the recesses of the switching cam in the circumferential direction, so that even due to shocks and vibrations there is no risk of the switching balls 6 penetrating the recesses of the switching cam 10 and thus releasing the freewheel.

Due to the outwardly pressed position of the switching balls 6, the brake shoes 3 are pressed outward around their noses 16, so that their wedge surfaces 15 are partially at a smaller distance from the inner drum surface than the diameter of the brake balls 5.

Fig. 8 shows the position of the individual parts at the beginning of the release process of the freewheel (phase 2): A torque acts on the drum 1 in the direction of arrow 14, but this does not cause any rotational movement because the drum is blocked in this direction. This leads to the formation of a reaction torque which either acts on the switching cam via the motor housing as shown in Fig. 1 or via the release lever 17 as shown in Fig. 4 and rotates it against the direction of arrow 14.

This rotation has progressed so far in the position shown in Fig. 8 that the switching balls 6 at the beginning

the recess of the switching cam 10 assigned to them. At the same time, the switching lever 7, which is connected to the switching cam 10 in a rotationally fixed manner, also rotates against the direction of the arrow 14, with a circumferential slot in the switching lever 7 moving along a driving pin 8 of the ball cage 2 without taking it with it. The freewheel is still completely blocked when the individual components are in the position shown in Fig. 8.

Fig. 9 shows the situation when the switching lever 7 is rotated further and, synchronously, the switching cam 10 connected to it (phase 3): The switching balls 6 have reached their radially innermost position, they have completely entered the recesses of the switching cam 10, the brake shoes 3 have also reached their radially innermost position and are resting on the cover hub 4.

The driving pin 8 of the ball cage 2 has moved from one end in the slot of the shift lever 7 to the other during the transition from phase 1 to phase 3, but the ball cage 2 has not twisted.

The brake balls 5 were pressed further into the cone between the wedge surfaces 15 and the inner surface of the drum 1, which widened during the transition from phase 1 to phase 3, by the spring-loaded pressure bolts 9, until they were prevented from any further movement in the circumferential direction by an inclined counter surface of the ball cage 2 and were loaded radially inwards by the inclined design of this counter surface.

Fig. 10 shows the situation after the release movement of the ball cage 2 has been carried out (phase 4): In phase 3, as explained above, the driving pin 8 of the ball cage reached the end of the slot in the switching lever 7, which is furthest in the direction of the arrow 14. As also

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if performed, the ball cage 2 was not moved during phases 1 to 3.

During phase 4, the ball cage 2 is now rotated by the further movement of the switching lever 7 (including the switching cam 10) against the direction of the arrow 14. In this case, the inclined surface 22 assigned to each brake ball 5, in conjunction with the spring-loaded pressure bolts 9, causes the brake ball 5 to move against the direction of the arrow 14.

Due to the inclination of the surfaces 22, a radial force component acts on the brake ball 5 towards the axis of the freewheel and the balls 5 are lifted off the inner surface of the drum 1, which prevents the balls from rubbing against this surface when the drum 1 is rotated in the direction of the arrow 14 and at the same time ensures that the drum 1 rotates slightly. This rotation of the drum 1 now begins due to the motor torque and causes a similar rotation of the spindle 11.

Fig. 11 shows the situation that arises when the drum 1 is braked during a twisting movement against the direction of the arrow 14 by an external torque, for example when the door connected to the spindle 11 has reached the closed position, and the locking position of the freewheel, which was not reached during the normal movement, is resumed by the increased motor torque thus caused.

Phase 5: By reversing the movement process compared to the sequence shown in Fig. 7 to 10, the reaction torque causes the switching lever 7, of which only the switching cam 10 connected to it and the recess can be seen in Fig. 11, to be rotated in the direction of arrow 14. In the phase 5 shown, the

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Switching balls 6 have just started their axially outward movement due to their exit from the recesses of the switching cam 10, but the brake shoes 3 are still in contact with the cover hub 4, so that the wedge surfaces 15 still assume their radially inner position.

In Fig. 12, the further progression of the locking process can be seen (phase 6): The switching balls 6 have climbed completely out of the recesses of the switching cam 10, but are still located at the edge of this recess. Likewise, the brake shoes 3 have already pivoted outwards and the driver pin 8 has reached the end of the recess of the switching lever 7, which, viewed in the direction of arrow 14, is at the rear end.

The switching cam 10 and the switching lever 7 have rotated further in the direction of arrow 14.

Up to the position shown, the ball cage 2 has not rotated from the beginning of phase 5, even though the brake balls 5 have already reached the braking position due to the radially outward movement of the brake shoes 6.

In Fig. 13, the situation in Fig. 7 (phase 1) is almost reached again: The ball cage 2 was twisted a little by further turning the switching lever 7 in the direction of arrow 14 and so the brake balls 5 were brought back into the brake cone between the wedge surfaces 15 and the inner surface of the drum 1, but also still rest on the inclined surfaces 22. The spring-loaded pressure bolts 9 hold the balls in this position.

By further rotating the ball cage by the angle δ after reaching phase 7 shown in Fig. 13, you return to the position of phase 1 (Fig. 7). This further rotation is done to ensure that the brake balls 5 are safely lifted off the inclined surfaces 22 of the ball cage and thus achieve a safe frictional connection.

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Compliance with the various movement phases and in particular the first extension of the brake shoes during locking and the subsequent pressing of the brake balls into the brake cone is recommended for safety reasons in order to prevent the brake shoes from being pushed radially outwards when the brake balls 5 are in the brake cone. This could then lead to damage or destruction of the device due to excessive forces on the switching balls or the corresponding button of the brake shoes or also due to contact between the brake balls and the brake shoes. This temporal sequence of the individual movements is ensured by the size and position of the slot in the switching lever 7.

The spring-loaded pressure bolts 9 have the task of compensating for manufacturing inaccuracies and tolerances and thereby ensuring that all (in the example shown, three) brake balls 5 actually reach the blocking position and exert a braking effect. If the balls 5 were pressed by a rigid plane of the ball cage 2, this would not be guaranteed for the reasons mentioned above.

The invention can be varied and modified in many different ways and does not have to have the design shown. It is possible to use rolling elements or non-rotationally symmetrical bodies instead of the brake balls and/or instead of the switching balls in order to reduce the pressure in the contact area. It is also possible to bring about the radial movement of the brake shoes 3 in a way other than by means of switching balls. This can involve direct interaction with a cam, or also adjustment levers which bring about direct adjustment in the form of toggle lever mechanisms or the like. Depending on the area of application and the forces occurring,

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The above-described temporal lag of the movement of the ball cage 2 is not always necessary.

It is also not necessary, as Fig. 6 shows, to combine the freewheel according to the invention directly with a motor for the drum 1 or a component connected thereto in a rotationally fixed manner, although this is advantageous in many applications due to the possibility of using the motor reaction torque to unlock the freewheel.

When combined with a motor 13 (Fig. 1) the coaxial arrangement to the drum 1 with direct drive of the spindle connected to it is shown and (Fig. 3 and 5) the offset parallel arrangement with transmission of the motor torque by means of gears. It is of course possible to transmit the motor torque by belts or the like, without having to change anything in the structure of the device according to the invention.

If the motor is not connected to the freewheel according to the invention, it is possible to use an electric drive (lifting magnet or similar) instead of the hydraulic or pneumatic cylinder-piston unit shown in Fig. 6 or, if release is only desired in exceptional cases, a manual operation.

It is easy to provide a manual emergency actuation device via the pivoting movement of the switching lever 7 between the stops 19, 20, as is indicated schematically in Figs. 4 and 6 by means of an arrow on the switching lever 7.

The term "rotationally fixed connection", which is used for the connection between the spindle and the drum in the application and the claims, also includes connections by means of belts, chains or intermediate gears and means that a defined rotation of the

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one component causes a defined rotation of the other component.

With hydraulic and pneumatic drives it is also possible to use the reaction torque when the door is opened to release the freewheel: To do this, the piston-cylinder unit, which is necessarily arranged between a point of attack on the door side and a point of attack on the door frame side, only has to be mounted in such a way that one of the points of attack is moved against the force of a spring when pressure is applied to the piston-cylinder unit and that the radial adjustment of the brake shoes takes place directly or via a rod.

The type of door construction, in particular its guidance, suspension and control, is not directly related to the device according to the invention, is familiar to those skilled in the field of door construction and therefore does not need to be explained here. It also makes no difference whether the spindle on which the freewheel acts, and thus the freewheel itself, is mounted in a fixed or movable manner with respect to the door frame. The latter is possible in particular with swing-sliding doors, where the spindle follows the opening movement of the door.

Claims (13)

- 15 - ^&tgr;&rgr;&pgr;'i rhr: 1. Drive for one or two-leaf sliding , pivoting or pocket doors, in particular vehicle doors, the drive of which comprises a rotatable spindle (11) which is operatively connected to a freewheel, the freewheel having a rotatable drum (1) which is connected to the spindle (11) in a rotationally fixed manner, and furthermore, inside the drum, clamping bodies which are movable within predetermined limits in the circumferential direction, such as brake balls (5), each of which is assigned a rotationally fixed wedge surface (15) of at least one brake shoe which is fixed in the circumferential direction, characterized in that the wedge surfaces (15) are radially movable and that their radial adjustment is preferably carried out by turning a switching cam (10). 2. Drive according to claim 1 with electric motor (13), characterized in that the motor (13) is attached to the housing of the freewheel and that the adjustment of the brake shoes (3), optionally by turning the switching cam (10), is carried out by the reaction torque of the motor directly or via a rod (18, 17 and 7). ' 3. Drive according to claim 1 with hydraulic or pneumatic drive unit, which is arranged between a door frame side and a door side engagement point, characterized in that one of the engagement points is displaceable against the force of a spring and that the radial adjustment of the brake shoes (3) takes place directly or via a rod by this displacement. 4. Drive according to one of claims 1 to 3, characterized in that each wedge surface (15) is arranged on its own pivotable brake shoe (3) close to the pivot axis and that the switching cam (10) acts on the area of the brake shoe (3) remote from the pivot axis. 5. Drive according to one of the preceding claims, characterized in that the switching cam (10) is arranged radially within a rotationally fixed cover hub (4) which carries the pivot axes of the brake shoes (3) and in that the movement of the switching cam (10) is transmitted to the brake shoes by switching bodies, e.g. switching balls (6) which are seated in passages in the cover hub. 6. Drive according to claim 5, characterized in that the switching cam (10) is designed in the form of a sleeve or tube, and that the spindle (11) on which the freewheel acts passes through it. 7. Drive according to one of the preceding claims, characterized in that the clamping bodies, such as brake balls (5), are arranged in recesses of a cage (2), that the extent of the recesses in the circumferential direction is greater than the extent of the clamping bodies and that the cage (2) is movable in the circumferential direction with respect to the wedge surfaces (15). 8. Drive according to claim 7, characterized in that spring-loaded pressure bolts (9) are arranged in the cage (2), which press the clamping bodies, such as brake balls (5), into the narrowing cone between the drum (1) and the wedge surfaces (15) when the cage (2) is rotated in this direction. 9. Drive according to claim 7 or 8, characterized in that the cage (2) has inclined surfaces (22) on the narrow side of the cone, the inclination of which runs in such a way that the recesses become smaller with increasing radius in the circumferential direction, and that these inclined surfaces (22) press the clamping rotation bodies, such as brake balls (5), out of the narrowing cone between the drum (1) and the wedge surfaces (15) when the cage (2) is rotated in this direction. -π &igr;&ogr;. Drive according to one of the preceding claims, characterized in that the motor housing is connected to the switching cam (10), optionally via a switching lever (7), and the drive shaft of the motor (13) is connected to the drum (1), optionally via a gear transmission, a belt or the like and optionally via the spindle (11). 11. Drive according to claim 1 for a two-leaf door with a symmetrical double spindle (11), characterized in that the freewheel between the individual spindles (11) is arranged essentially in the middle of the door opening. 12. Drive according to claim 1 for a double-leaf door with pneumatic or hydraulic drive, characterized in that the drive acts on one of the door leaves and that the two door leaves are connected to one another via a symmetrical double spindle, in the middle of which the freewheel is arranged, and that the adjustment of the brake shoes (3), if necessary by turning the switching cam (10), is carried out by a hydraulic or pneumatic cylinder-piston unit (21) which acts on a switching lever (7). 13. Drive according to claim 12, characterized in that the hydraulic or pneumatic cylinder-piston unit (21) has a single-acting cylinder provided with a return spring.