192 clutches and power-stop control – Clutches – Operators
Reexamination Certificate
2001-07-19
2004-03-09
Rodriquez, Saul (Department: 3681)
192 clutches and power-stop control
Clutches
Operators
C192S098000, C074S424820
Reexamination Certificate
active
06702084
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a clutch operator arrangement for introducing an actuating force into a friction clutch.
2. Description of the Related Art
DE 195 47 081 A1 has disclosed an actuating device for a clutch, in which a clutch operator arrangement has two ramp regions which can rotate with respect to one another about an axis of rotation, follow one another in the axial direction and between which rolling bodies designed in the form of balls are positioned. If one of the components which have ramp surfaces is driven in rotation, for example by being driven by a Bowden cable, the ramp surfaces which lie axially opposite one another move, with a rolling movement of the balls, with the result that the two components are shifted axially with respect to one another and a clutch release force is generated.
EP 0 478 427 A1 also discloses an arrangement of this type, in which associated groups of ramp surfaces, with dedicated ball elements between them, can move with respect to one another in order to generate the axial thrust force.
One drawback of these known clutch operator mechanisms which operate using pairs of ramp surfaces which lie opposite one another is that, on account of the ramp surface pairings which follow one another in the circumferential direction, the circumferential angle sector over which ramp surfaces of this nature can extend is restricted, primarily also because a plurality of ball elements of this nature have to be distributed in the circumferential direction in order to achieve uniform axial force transmission or generation. To generate a predetermined axial movement on the output side, therefore, a relatively large ramp pitch is required, and this in turn requires relatively high input forces in order ultimately to be able to work against the force of a force accumulator.
Furthermore, clutch operator mechanisms which operate, for example, with a clutch release lever or with piston/cylinder systems arranged concentrically with respect to the axis of rotation are known, but these systems are comparatively large and often undesirable.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a clutch operator arrangement which, while being of small overall size and of simple structural design, is able to generate high actuating forces.
According to the invention, this object is achieved by the fact that the clutch operator arrangement comprises a ball screw arrangement.
Ball screws are used, for example, in machine tools in order to convert rotary movements into linear translation movements. The present invention makes use of the fact that, ultimately, the ball screws do not have the rotation angle limitation which is present in the prior art. It is therefore possible, even with a relatively small input force, to generate relatively high actuating forces, by means of which the force accumulators used in friction clutches, such as for example diaphragm springs, can be acted on and actuated. A further significant advantage of ball screws of this type is that they are able to transmit forces in both axial directions, so that they can be used with both pulled and pushed clutches, without having to make design changes to the basic structure of the region which converts the rotational movement into the translational movement.
By way of example, it is possible to provide for the ball screw arrangement to comprise a spindle element, which on an outer circumferential surface has a first groove arrangement, a nut element, which surrounds the spindle element and on its inner circumferential surface has a second groove arrangement, a plurality of ball elements, at least some of which engage in the first groove arrangement and the second groove arrangement, the spindle element being rotatable about an axis of rotation with respect to the nut element and, in the event of rotation of the spindle element with respect to the nut element about the axis of rotation, the ball elements which engage in the first groove arrangement and the second groove arrangement, by rotating about a respective ball axis of rotation, rolling along the first groove arrangement and the second groove arrangement, and for one element out of the nut element and the spindle element to be or be able to be supported on a substantially stationary assembly, the friction clutch to be or be able to be acted on by the other element out of the nut element and spindle element, and at least one element out of the nut element and the spindle element to be able to be driven to rotate about the axis of rotation, in order to produce a relative displacement between the spindle element and the nut element in the direction of the axis of rotation.
According to a first alternative design variant, a drive arrangement which engages on that element out of the nut element and the spindle element which is intended to act on the friction clutch, in order to set this element in rotation about the axis of rotation, may be provided for the purpose of generating the translational movement.
Such a design variant of the drive arrangement may, for example, be provided if the spindle element is fixed, on the substantially stationary assembly, against rotation about the axis of rotation and movement in the direction of the axis of rotation, and if the nut element can be driven to rotate about the axis of rotation by means of the drive arrangement.
Since, in an arrangement of this type, the drive arrangement ultimately engages on the element which moves in translation in the axial direction, i.e. the nut element, it is necessary to ensure that the drive arrangement is also able to follow this translational movement. In an embodiment which is very simple to implement, it is possible to provide for the drive arrangement to comprise a cable pull element which engages on the nut element. Alternatively, however, it is possible for the drive arrangement to comprise a drive slide element, preferably a drive lever element, which interacts with the nut element for rotational movement driving in an interaction region.
In a further alternative design variant of the clutch operator arrangement according to the invention, it is possible to provide a drive arrangement which engages on that element out of the nut element and the spindle element which is intended to be supported on the substantially stationary assembly, in order to set this element in rotation about the axis of rotation. This variant has the advantage that the drive arrangement, through interaction with an assembly which is substantially stationary in the axial direction, does not have to follow a translational movement. In an embodiment of this nature it is possible, for example, to provide for the spindle element to be mounted on the substantially stationary assembly so as to rotate about the axis of rotation, while it substantially cannot be displaced in the direction of the axis of rotation, and for the nut element to be held in such a way that it can be displaced in the direction of the axis of rotation but substantially cannot rotate about the axis of rotation. To prevent the nut element from also executing a corresponding rotational movement in the event of rotation of the spindle element, it is furthermore possible to provide a rotational-movement blocking arrangement, by means of which the nut element is connected to the substantially stationary assembly in such a manner that it can move in the axial direction and is stopped from rotating about the axis of rotation.
In this embodiment, the drive arrangement may have a toothed element, preferably a rack element, which meshes with mating toothing, preferably outer circumference toothing, provided on the spindle element.
Furthermore, the ball screw arrangement according to the invention is preferably designed in such a manner that the first groove arrangement has at least one first thread, preferably with a plurality of turns, that the second groove arrangement has at least one second thread assigned to each first thread of the first groove arrange
Dau Andreas
Ebert Angelika
Grosspietsch Wolfgang
Heiartz Markus
John Thomas
Cohen & Pontani, Lieberman & Pavane
Mannesmann Sachs AG
Rodriquez Saul
Williams Eric M.
LandOfFree
Clutch operator arrangement does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Clutch operator arrangement, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clutch operator arrangement will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3238850