EP0064763B1 - Drive, in particular an adjusting drive in a motor vehicle - Google Patents

Description

The invention relates to an adjustment drive, in particular in a motor vehicle, in particular for a window lifter, with a main drive, an auxiliary drive, a releasable clutch in the force path of the main drive and a wrap spring brake element, wherein the wrap spring brake element is widened when the restoring force exerted by the clutch output member.

In motor vehicles, adjustment movements are increasingly being carried out with the aid of adjustment drives (window lifters, seat adjustment or the like). If the main drive fails, e.g. B. a drive electric motor, it is very desirable if adjustment movements can still be carried out, with the help of an auxiliary drive that engages the output member of the clutch while removing the rotary coupling between the main drive-side drive member and output member to an emergency adjustment even with a blocking main drive to enable.

Adjustment drives of the type mentioned are known (DE-A-2 705 627 and DE-A-2915669). The wrap spring brake element is used exclusively to prevent an automatic return movement of the element driven by the adjustment drive when the main drive is at a standstill. The self-weight of the driven element (e.g. the window) and the shaking forces during the journey can be considered as restoring forces. In these cases, the wrap spring brake element is expanded by the output member, so that it brakes against a stationary inner circumferential surface of a brake housing. When the main drive is operating, the force transmission takes place due to entrainment of the wrap spring brake element in the sense of a reduction in diameter. In the case of the known adjusting drives mentioned above, the decoupling takes place in the event of a breakdown of the wrap spring brake element independently by axially moving corresponding coupling parts apart.

From FR-A-2378 164 it is known to provide an overload slip clutch in the force path between the electric motor and the cable drum in an electric motor window regulator. This consists of a wrap spring, which is supported on the inner circumference of an electric motor-side drive element and, in the normal case, takes along an output element which is rigidly connected to the cable drum and is designed as a claw part. In the event of an overload, the wrap spring is pulled together by the claw part and can therefore slide along the inner circumference of the drive part in order to release the slip clutch. A manual override if the electric motor fails is not provided. The manual rotation of the rope drum when the electric motor is at a standstill is very difficult, if not impossible, since the rope drum would have to be twisted with a force that exceeds the triggering force of the overload friction clutch.

The object of the invention is to provide a drive of the type mentioned, which offers the possibility of a quick and easy to start and stop manual override.

This object is achieved in that when the main drive is in operation, the force transmission takes place by widening the wrap spring brake element, while in operation of the auxiliary drive there is a reduction in the diameter of the wrap spring brake element for decoupling the main drive. In the event of a failure of the drive motor driving the drive member, the drive element can be rotated in the desired manner in one or the other direction of rotation by appropriate rotation of the decoupling element, the rotary coupling between the drive member possibly blocked by the stationary electric motor and the driven member being completely released. After the defect on the drive element has been eliminated, the adjustment drive according to the invention is immediately ready for operation again, with only the auxiliary drive, for example a drive crank, possibly being separated from the decoupling element.

Compact design and reliable function of the adjustment drive are ensured in a further development of the invention in that a hollow cylinder element, on the inner circumferential surface of which the wrap spring brake element is supported, is connected in a rotationally fixed manner to a main drive-side drive member, that the output member of the clutch is formed by a first claw part, which is in operation of the main drive presses against one of the ends of the wrap spring brake element in the sense of widening the wrap spring brake element, and that a coupling element which is connectable to the auxiliary drive and is designed as a second claw part is provided, which presses against one of the ends of the wrap spring brake element during operation of the auxiliary drive in the sense of a diameter reduction of the wrap spring brake element , and which is designed to take the first coupling part.

In a preferred embodiment, the disengaging element can be connected to the auxiliary drive via a plug-in coupling; such a coupling is easy to operate and requires little installation space, especially if the decoupling element is provided with an internal polygon for a manual control element.

In order to prevent the transmission of vibrations and / or impacts, for example impact impacts, between the drive member and the output member and thereby to reduce the noise and the mechanical wear, it is proposed that the drive element on an end face perpendicular to its axis of rotation with axially protruding, on a circumferential line distributed webs is formed between engage the webs correspondingly formed on the hollow cylinder element, an intermediate space having a spring element, preferably a rubber element, being formed in the circumferential direction between the victories.

A particularly compact arrangement in the axial direction is obtained in that a bearing collar for the rotary mounting of the hollow cylinder element or of the drive element is formed on the drive element or on the hollow cylinder element.

Characterized in that the hollow cylinder element, as proposed, is provided with a metallic insert sleeve having the inner peripheral surface, low-wear operation and a consistently high coefficient of friction between the wrap spring and the inner peripheral surface are achieved. The hollow cylinder element itself can be produced inexpensively from less wear-resistant material, for example from plastic.

In a preferred embodiment, the first claw part is formed in the region of the two ends of the wrap spring with a flat, preferably approximately dovetail-shaped driver, which is attached to an output shaft and is perpendicular to the axis of rotation of the links and projects radially beyond the inside wrap spring diameter. In this way, on the one hand, reliable contact is achieved between the inwardly bent two ends of the wrap spring and the first claw part and, on the other hand, secure guidance of the wrap spring windings between the two drivers projecting radially outward beyond the wrap spring inner diameter.

To reduce the manufacturing costs, the two drivers can be congruent and / or integrally formed with the drive shaft.

Due to its compact and robust construction and the possibility of providing an always effective manual override, the drive according to the invention is particularly suitable as a drive for a motor vehicle window regulator. For this purpose, it is proposed that the output member is connected in a rotationally fixed manner to a pinion which meshes with a threaded cable of a cable window lifter or a toothed segment of a rod window lifter. However, the output member can alternatively be connected in a rotationally fixed manner to a cable drum for the cable of a cable window lifter.

In a mechanically stable and yet easy to manufacture embodiment, the decoupling element is formed with a partial hollow cylinder which forms the second claw part and is arranged between the wrap spring and the output shaft passing through the wrap spring, the axially extending edges of which interact with the radially inwardly bent ends of the wrap spring.

A simple mounting of the decoupling element, which in turn requires only little installation space in the axial direction, is formed in such a way that the decoupling element is rotatably mounted in a bearing opening of a drive housing with an axial bearing bolt which may be formed with the polygon. In order to increase the durability, the decoupling element, which always takes the members with them even in normal operation, can also be mounted on the first claw part by means of a collar which rests on the circumference of a driver disk that carries one of the drivers and is attached to the drive shaft.

• Figur 1 eine Schnittansicht des erfindungsgemäßen Antriebs im Schnitt entlang der Linie I-1 in Fig. 2 und 3 ;
• Figur 2 eine Schnittansicht der Anordnung nach Fig. 1 im Schnitt entlang der Linie 11-11 ; und
• Figur 3 eine Schnittansicht eines Einzelteils der Anordnung nach Fig. 1 im Schnitt entlang der Linie 111-111.

The invention is explained below using an exemplary embodiment with reference to the drawing. It shows :

• Figure 1 is a sectional view of the drive according to the invention in section along the line I-1 in Figures 2 and 3;
• Figure 2 is a sectional view of the arrangement of Figure 1 in section along the line 11-11. and
• Figure 3 is a sectional view of an individual part of the arrangement of FIG. 1 in section along the line 111-111.

The drive shown in FIGS. 1 and 2, generally designated 10, establishes the connection between an electric drive motor, not shown, on the motor shaft of which a worm 12 shown on the right in FIG. 1 is fastened and a threaded cable window lifter in a motor vehicle, the threaded cable 14 in Fig. 1 is drawn lower left. The frictional connection between worm 12 and threaded cable 14 runs in sequence over the following coaxially mounted rotating parts: a drive member 16 in the form of a worm wheel meshing with the worm 12, a hollow cylindrical element 18 which is non-rotatably coupled to the drive member 16 and torsionally vibration-damped via a damping rubber part 20 , a wrap spring 22, which is supported on the inner circumference of an insert sleeve 24 inserted into the hollow cylindrical element 18, and an output member 26, the upper end of which in FIG. 1 is provided with two drive disks 28, which form a first claw part and interact with the wrap spring 22, and on whose lower end a pinion 30 engaging in the threaded cable 14 is rotatably pushed on. Another rotating part, the disengaging element 32 adjoining the output member 26 upwards, is not in the force path between the screw 12 and the threaded cable 14; it only rotates during normal operation. As will be described in more detail, the disengaging element 32 is used in the event of a fault, for. B. with a defective drive motor to allow manual operation of the window regulator.

The rotating parts 16 to 32 described above are mounted in a two-part housing with a lower housing base 34 in FIG. 1, a housing cover 36 with an intermediate sealing ring 38 and a cover 40 attached to the underside of the housing base 34, which serves as a guide for the threaded cable 14 and the threaded cable 14 and the pinion 30 against contamination downwards covers. The housing can be made of plastic or metal.

The vibration-damped, rotationally fixed connection between the drive member 16 and the hollow cylinder element 18 is illustrated in FIG. 3. In the section of FIG. 3, only the hollow cylinder element 18 and the damping rubber part 20 are shown in section; the drive member 16, however, is omitted. It can be seen that the hollow cylinder element 18 is formed with a bearing disk 44 perpendicular to the axis of rotation 42 in FIG. 1, from which a hollow cylinder section 46 adjoins upwards in FIG. 1 (indicated by dotted lines in FIG. 3) in the, as already mentioned, the insert sleeve 24 is inserted. The bearing disc 44 is formed with a central bearing opening 48, with which the hollow cylinder element 18 is rotatably mounted on a correspondingly dimensioned bearing collar 50 of the drive element 16. In order to enlarge the area of the pivot bearing in the axial direction and thus to increase the tilting stability, a bearing neck 52 which projects downward and encompasses the bearing collar 50 is formed on the bearing disk 44, as can also be seen in FIG. 3.

From this bearing neck 52, there are three webs 54 distributed in the radial direction on the circumference of the bearing disc 44, each of which ends shortly before the outer circumference of the bearing disc 44 is reached. As shown in FIG. 1, the webs 54 project downward in the axial direction. In a corresponding manner, the drive member 16 is also formed with three webs 56, the side surfaces 58 of which are parallel to the axis of rotation 42 are indicated in FIG. 3 with dash-dot lines. The webs 56 are each at half an angle between the webs 54, with a space remaining between these webs 54 and 56 in the circumferential direction, which is each completely filled by a correspondingly shaped section 60 of the damping rubber part 20. As shown in FIG. 1, successive sections 60 are connected to one another in each case by a correspondingly thinner connecting section 62. The damping rubber part 20 is therefore in one piece and thus inexpensive to manufacture and assemble. The hollow cylinder element 18 is thus rotatably mounted on the drive member 16 via the bearing collar 50 and the bearing neck 52, but slight torsional vibrations which are cushioned and damped by the sections 60 are possible in both directions from the rest position shown in FIG. 3. The drive member 16 is in turn rotatably mounted on the one hand on a bearing neck 66 extending into a corresponding downwardly open bearing opening 34 and on the other hand on a cylindrical output shaft 68 of the output member 26 which passes through a bearing opening 70 of the bearing neck 50.

The shape of the wrap spring 22 inserted into the insert sleeve 24 can be seen from FIGS. 1 and 2. Accordingly, the wrap spring 22 is wound in the manner of a solenoid, with both ends, the upper end 72 visible in FIG. 1 and the lower end 74 only visible in FIG. 2, being bent radially inward. The outside diameter of the relaxed wrap spring 22 is somewhat larger than the inside diameter of the insert sleeve 24, so that the wrap spring 22 inserted into the insert sleeve 24 presses radially outward against the inner circumferential surface 76 of the insert sleeve 24.

With the ends 72 and 74 of the wrap spring 22, the driving disks 28 interact in accordance with the respective rotational position, specifically the driving disk in FIG. 1 with the upper end 72 and the lower driving disk 28 with the lower end 74. For this purpose, the two driving disks 28 are each formed with an approximately dovetail-shaped driver 78 which, as shown in FIG. 2, extends to the inner circumferential surface 76 of the insert sleeve 24. In this way, it is achieved that the ends 72 and 74 are not bent over by the corresponding drivers 78 even at high torques, since the drivers 78 with their outer corners directly apply the corresponding torque to the ends 72 and 74 in each of the bent ends Transfer circumferential wrap spring section. It is also advantageous that the two catches 78 prevent the windings of the wrap spring 22 lying between them from moving axially upwards or downwards. As can be seen from FIG. 1, the two drive disks 28 are pushed onto both sides of a collar 80 of enlarged diameter of the output shaft 68 and are soldered or welded there. However, other types of connection are also possible, and the drive plates can also be formed in one piece with the output shaft.

At the lower end of the output shaft 68, the pinion 30 is non-positively pushed onto a reduced-diameter, corrugated section 82.

The decoupling element 32 consists of a circular disk 84 perpendicular to the common axis of rotation 42, from which an axial bearing pin 86 projects upwards in FIG. The bearing pin 86 is rotatably mounted in a corresponding bearing opening 90 in the housing cover 36. A partial hollow cylinder 92, whose cylinder axis coincides with the axis of rotation 42, extends downward from the circular disk 84. As can be seen in FIG. 1, the partial hollow cylinder 92 almost reaches in the axial direction up to the bearing disk 44 of the drive member 16. The cross section of the partial hollow cylinder 92 shown in FIG. 2 corresponds to a circular ring from which a sector has been cut out. The edges of the partial hollow cylinder 92, which run in the axial and radial directions, are designated by 94 in the figures. As can be seen from FIG. 2, these edges 94 interact with the corresponding ends 72 and 74 of the wrap spring 22 depending on the direction of rotation, as will be explained in more detail below will be tert.

In Fig. 1 is further shown a slightly radially inwardly projecting collar 96 formed at the upper axial end of the TeilhohlzylinJers 92, which rests on the outer periphery of the drive plate 28 and in this way provides for an additional rotary bearing of the disengaging element 32, namely on the output member 26.

The mode of operation of the drive described above will be explained below. In normal operation, i.e. H. when the window is actuated by the electric drive motor, not shown, via the worm 12 connected to it, the frictional connection, as mentioned at the beginning, runs via the rotating parts 16 to 30 to the threaded cable 14. The hollow cylinder element 18 is rotatably independent of the output member 26 via the wrap spring 22 coupled from the direction of rotation. If the hollow cylinder element 18 is rotated, for example clockwise (arrow A), while the drive motor is running, via the worm 12, the drive member 16 and the damping rubber part 20, after a short rotation the end 72 comes to rest against the driver 78, which was still stationary Rotation in direction A is exerted by the catch 78 on the wrap spring 22 in the longitudinal direction of a force corresponding to the acting torque, which the spring 22 attempts to expand, which leads to the spring 22 being pressed against the inner peripheral surface 76 with increasing force. The result is a reliable frictional engagement between wrap spring 22 and insert sleeve 24, wherein the frictional force increases with the torque applied.

Even when the hollow cylinder element 18 is rotated in the direction of rotation opposite to the direction of rotation A, the output element 26 is also carried, in which case the lower end 74 of the wrap spring 22 in FIG. 1 interacts with the lower driver 78. In both cases, the disengaging element 32 is only rotated.

If there is a defect in the drive motor, the window lifter can still be operated by hand immediately by bringing in the manual override key already mentioned on the vehicle tool kit and inserting it with its external polygon into the internal polygon 88. When the key is rotated, for example in direction B, the partial hollow cylinder 92 accordingly also rotates in this direction (see FIG. 2). After a short rotation, the edge 94 lying further down in FIG. 2 comes to bear against the upper end 72 of the wrap spring 22. When the winder spring 22 is turned further, the edge 94 pulls on the wrap spring 22 in its longitudinal direction, which causes the wrap spring 22 to lift off from the inner circumferential surface 76 and thus a loosening of the frictional engagement between wrap spring 22 and hollow cylinder element 18. With a further rotation of the disengaging element 32, the entrained upper end 72 comes to rest against the entrainer 78, which is also entrained during the further rotational movement. The output member 26 is thus rotationally coupled to the disengaging element 32. In contrast, the rotary coupling between the drive member 16 and the output member 26 is released, since the wrap spring 22 is no longer in frictional engagement with the hollow cylinder element 18. The adjustment movement of the window lifter with the aid of the disengaging element 32 is therefore not impeded by a possibly blocking electric drive motor.

Due to the symmetry of the arrangement, the window lifter can of course also be actuated in the opposite direction without any problems, in which case the partial hollow cylinder 92 with its upper edge 94 in FIG. 2 via the lower end 74 of the wrap spring 22 in FIG. 1 to the lower driver 78 presses. In both cases, the window can be quickly warped with the help of the key, since the key acts directly on the output member 16 and the pinion 30 connected to it without large intermediate translation.

After the defect in the drive motor has been remedied, the drive 10 is immediately ready for operation again; you only have to remove the key.

Claims (16)

1. Displacer drive (10), especially in a motor vehicle, especially for a window winder, having a main drive (12), an auxiliary drive (32, 88), a disengageable coupling (18, 26) in the force path of the main drive and having a looping spring brake element (22), where an expansion of the looping spring brake element (22) takes place when a return force is exerted by the drive-output member (26) of the coupling (18, 26), characterised in that when the main drive (12) is in operation the force transmission takes place by expansion of the looping spring brake element (22), while when the auxiliary drive (32, 88) is in operation a reduction of diameter of the looping spring brake element (22) takes place for the uncoupling of the main drive (12).

2. Displacer drive according to Claim 1, characterised in that a hollow cylinder element (18), on the internal circumferential surface (76) of which the looping spring brake element (22) bears in the rest position, is connected fast in rotation with a drive member (16) of the main drive, in that the drive-output member (26) of the coupling is formed by a first claw part (28, 78) which when the main drive (12) is in operation presses against one of the ends (72, 74) of the looping spring brake element in the direction of an expansion of the looping spring brake element (22), and in that an uncoupling element (32) connectable with the auxiliary drive and formed as second claw part (92, 94) is provided which presses, when the auxiliary drive is in operation, against one of the ends (72, 74) of the looping spring brake element (22) in the direction of a reduction of diameter of the looping spring brake element (22), and which is formed for the entraining of the first claw part.

3. Displacer drive according to Claim 1 or 2, characterised in that the auxiliary drive is formed by a manual drive.

4. Displacer drive according to one of Claims 2 and 3, characterised in that the uncoupling element (32) is connectable with the auxiliary drive through a plug-in coupling.

5. Displacer drive according to Claim 4, characterised in that the uncoupling element (32) is provided with an internal polygon (88) for a manual actuation element.

6. Displacer drive according to one of Claims 2 to 5, characterised in that the drive member (16) is formed, on an end face perpendicular to its axis (42) of rotation, with axially protruding webs (56) distributed on a circumferential line, between which there engage webs (54) correspondingly formed on the hollow cylinder element (18), while an interspace having a spring element, preferably a damping rubber part (20, 60), is formed in the circumferential direction in each case between the webs (54, 56).

7. Displacer drive according to one of Claims 2-6, characterised in that on the drive member (16) or on the hollow cylinder element (18) a bearing collar (50) is formed for the rotational bearing of the hollow cylinder element (18) or of the drive element respectively.

8. Displacer drive according to one of Claims 2-7, characterised in that the hollow cylinder element (18) is provided with a metallic insert sleeve (24) having the internal circumferential surface (76).

9. Displacer drive according to one of Claims 2-8, characterised in that the first claw part is provided in the region of each of the two ends (72, 74) of the looping spring brake element (22) with a flat engaging member (78) fitted on a drive-output shaft (68), perpendicular to the axis (42) of rotation of the members (drive-input member 16, drive-output member 26) and protruding radially beyond the internal diameter of the looping spring, which engaging member is preferably approximately of dovetail form.

10. Displacer drive according to Claim 9, characterised in that the two engaging members (78) are made coincident.

11. Displacer drive according to Claim 9 or 10, characterised in that the two engaging members (78) are made in one piece with the drive-output shaft (68).

12. Displacer drive according to one of Claims 1-11, characterised in that the drive-output member (26) is connected fast in rotation with a pinion (30) which meshes with a threaded cable (14) of a cable-type window winder of a toothed segment of a rod-linkage-type window winder.

13. Displacer drive according to one of Claims 1-11, characterised in that the drive-output member (26) is connected fast in rotation with a cable drum for the cable of a cable-type window winder.

14. Displacer drive according to one of Claims 2-13, characterised in that the uncoupling element (32) is formed with a partial hollow cylinder (92) forming the second claw part and arranged between the looping spring (12) and a or the drive-output shaft (68) passing through the looping spring (12), of which cylinder the edges (94) extending in the axial direction co-operate with the radially inwardly bent-over ends (72, 74) of the looping spring brake element (22).

15. Displacer drive according to one of Claims 5-14, characterised in that the uncoupling element (32) is rotatably mounted with an axial bearing bolt (86), which may be formed with the internal polygon (88), in a bearing opening (90) of the drive housing.

16. Displacer drive according to Claim 15, characterised in that the uncoupling element (32) is mounted on the first claw part by means of a collar (96) resting on the circumference of an engaging disc (28) carrying the engaging member (78) and fitted on the drive-output shaft (68).

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