Actuating mechanism for a clutch actuator with multi-part actuating element

Abstract

Actuating mechanism (9) for a clutch actuator, comprising: - an actuating element (6) designed to actuate with an actuating force (F) B ) acted upon and moved by this in an actuation direction (X), - a transmission element (1) designed to perform a displacement parallel to the direction of actuation (X), - at least one clamping element (2) designed to clamp when the actuating element (6) is subjected to the actuating force (F) B ), by forming a clamp, a transmission of the actuating force (F B ) to enable the transmission element (1), wherein the actuating element (6) and the at least one clamping element (2) are designed to be movable relative to each other in a circumferential direction (Y) oriented around the actuating direction (X), wherein a friction element (2a) and a counter surface (1a) are provided between the at least one clamping element (2) and the transmission element (1), which are configured such that when the actuating force (F) is applied B ) on the actuating element (6) between the friction element (2a) and the counter surface (1a) a reinforcing contact force (F) V ) acts, forming the clamping force, whereby the opposite surface (1a) is designed as the surface of a groove extending along the direction of actuation (X), and the friction element (2a) is designed as a spring which is designed to be guided in the groove along the direction of actuation (X).

Description

[0001] The present invention relates to an actuating mechanism, in particular for a clutch actuator, and to a clutch actuator having such an actuating mechanism.

[0002] Such actuating mechanisms convert an actuating force applied to an actuating element into a displacement of a transmission element, for example, to disengage a clutch by introducing the displacement into the clutch. However, other technical devices can also be actuated using such an actuating mechanism.

[0003] Furthermore, however, relative movements between the actuating element and the transmission element must be permitted under certain conditions, for example, to compensate for wear on the technical device, especially on the clutch's friction linings, thereby avoiding idle travel that would have to be overcome during actuation. The connection between the actuating element and the transmission element must be designed to prevent slippage during actuation, in particular to prevent safety-critical situations, such as the unwanted engagement of a clutch.

[0004] To transmit the actuating force to the transmission element, a mechanism is typically provided that is designed to create a locking connection between the actuating element and the transmission element when the actuating force is applied. This locking connection is achieved, for example, by means of a clamp. Special clamping elements are provided to create the clamping connection, which, for example, clamp with the transmission element when the actuating force is applied to the actuating element.

[0005] In the case of existing clamping, high transverse forces can occur in the clamping elements transversely or in the circumferential direction to the direction of displacement of the transmission element, which means that the clamping elements are at risk of breaking.

[0006] In addition, tolerances can result in uneven actuation of the individual clamping elements by the actuating force, which can also cause damage to the clamping elements.

[0007] An actuating mechanism for operating a friction clutch is known from DE 197 29 997 A1.

[0008] It is an object of the present invention to provide an actuating mechanism of the type described above and a clutch actuator which solve the problem described above.

[0009] This problem is solved by the subject matter of the independent claims. Advantageous further developments are the subject matter of the dependent claims.

[0010] According to the invention, an actuating mechanism for a clutch actuator is provided, comprising: - an actuating element which is designed to be subjected to an actuating force and to be displaced by this force in an actuating direction, - a transmission element designed to perform a displacement parallel to the actuating direction, - at least one clamping element which is designed to enable the actuating force to be transmitted to the transmission element by forming a clamp when the actuating element is subjected to the actuating force, wherein the actuating element and the at least one clamping element are designed to be movable relative to one another in a circumferential direction oriented around the actuating direction.

[0011] The transmission element is preferably designed as a rod, with the actuation direction preferably parallel to the rod axis, particularly preferably identical to the rod axis. The transmission element further preferably has a circular cross-section.

[0012] The transmission element is preferably hollow in order to pass functional elements, for example a drive shaft for a clutch, through it.

[0013] The clamping elements are preferably arranged on a circle around the actuating direction and / or around the rod axis, wherein they are particularly preferably regularly spaced from one another.

[0014] The at least one clamping element is further preferably subjected to an elastic preload force counter to the actuating direction in order to effect a return movement of the at least one clamping element counter to the actuating direction when the actuating force is removed. This elastic preload force is preferably generated by a spring element, such as a coil spring.

[0015] The actuating element is further preferably subjected to an elastic preload force counter to the actuating direction in order to cause a return movement of the actuating element counter to the actuating direction when the actuating force is removed. This elastic preload force is preferably generated by a spring element, such as a coil spring.

[0016] The actuating element is preferably designed concentrically to the rod axis and / or to the actuating direction.

[0017] Due to the possibility of relative movement in the circumferential direction, a compensating movement can occur between the actuating element and the at least one clamping element when the actuating force builds up to a predetermined value, so that the occurrence of high transverse forces in the at least one clamping element, as described above, is avoided.

[0018] The actuating mechanism is preferably designed to reduce the clamping between the transmission element and the at least one clamping element when no actuating force is applied to the actuating element and / or when the actuating element or the at least one clamping element is in an end position, so that a relative movement of the transmission element with respect to the at least one clamping element can take place parallel to the actuating direction.

[0019] The actuation direction is preferably designed as a straight line.

[0020] Preferably, the at least one clamping element is designed to deflect the actuating force into a supporting force which, as a contact force on the transmission element, causes the clamping to be established.

[0021] Preferably, the magnitude of the supporting force is proportional to the magnitude of the actuating force, preferably higher. This is achieved by the structural design of the at least one clamping element. For this purpose, the at least one clamping element is preferably designed to bend in relation to the actuating direction.

[0022] Preferably, the actuating element and the at least one clamping element are designed to be movable relative to one another in the circumferential direction when the clamping is not yet fully formed and / or when the clamping is fully formed. Thus, the compensating movement is possible when the clamping is partially and / or fully formed, so that even significantly higher actuating forces can be applied to the actuating element without the risk of excessive transverse forces occurring in the at least one clamping element or without causing damage to the at least one clamping element.

[0023] Preferably, the actuating mechanism is designed such that the actuating force is transmitted in the actuating direction from the actuating element to the at least one clamping element directly or via at least one intermediate element, wherein the actuating element has a transmission surface which is designed to transmit the actuating force to the at least one clamping element or to an intermediate element.

[0024] The transmission surface is preferably oriented perpendicular to the actuation direction. The transmission surface is preferably designed as a plane, particularly preferably as the surface of an annular piston. The transmission surface is preferably designed to transmit the actuation force without additional forces in the circumferential direction. This advantageously prevents the introduction of a force component in the circumferential direction into the at least one clamping element.

[0025] The actuating mechanism is preferably designed such that the actuating element and the at least one clamping element are in contact with each other, either directly or via at least one intermediate element, at least when the actuating element is subjected to the actuating force. This contact particularly preferably also exists when no actuating force is applied to the actuating element. This advantageously ensures rapid transmission of the actuating force to the at least one clamping element without the actuating element first having to travel a free travel.

[0026] This contact is further preferably designed to allow relative movement in the circumferential direction. This contact is preferably designed as a sliding contact, wherein the relative movement in the circumferential direction can take place in the form of the corresponding elements sliding relative to one another.

[0027] Preferably, a rolling element is provided as at least one intermediate element. Spherical or cylindrical rolling elements or other suitable rolling elements can be provided as rolling elements. Furthermore, a rolling bearing, such as a ball or roller bearing, can also be provided instead of a simple rolling element. The provision of a rolling element advantageously ensures that relative movement in the circumferential direction can occur very easily.

[0028] The at least one clamping element is preferably arranged at an angle relative to the actuation direction. This preferably achieves a transmission of the actuation force to the transmission element, while simultaneously exerting a contact force perpendicular to the actuation direction between the at least one clamping element and the transmission element.

[0029] The at least one intermediate element is preferably in contact with the at least one clamping element in such a way that it enables the actuating force to be introduced parallel to the actuating direction, but offset from it.

[0030] Preferably, the at least one clamping element is elastic.

[0031] The actuating element is preferably designed to displace the at least one clamping element counter to the actuating direction, at least over part of the entire displacement, when displaced counter to the actuating direction. In this way, the at least one clamping element can also be moved back, for example, when the actuating element is moved counter to the direction of displacement by a return spring. For this purpose, a geometry, preferably a stop, is preferably formed on the actuating element, which comes into contact or is already in contact with the at least one clamping element when the actuating element is moved counter to the actuating direction.

[0032] The actuating element preferably has a groove designed to receive the at least one clamping element. This groove is preferably designed to guide the at least one clamping element in the circumferential direction, so that the clamping element is movable relative to the actuating element in the circumferential direction.

[0033] The actuating mechanism is preferably designed to release the clamping when no actuating force is applied to the actuating element and / or when the actuating element or the at least one clamping element is in an end position, in order to enable a relative movement of the transmission element with respect to the actuating element. This advantageously ensures that the clamping is released at the latest when the actuating element and / or the at least one clamping element are in the respective end position, and a compensating movement of the transmission element can take place.

[0034] Preferably, the end position of the actuating element and / or of the at least one clamping element is defined by a stop which is stationary relative to the transmission element, the at least one clamping element and / or the actuating element.

[0035] The at least one clamping element is preferably designed to rest against the stop in its end position, with a force acting between the stop and the at least one clamping element causing the clamp to be released. This actively assists in releasing the clamp, ensuring that the clamp is released at the latest in the end position of the clamping element, allowing a compensating movement of the transmission element.

[0036] The actuating mechanism is preferably designed to apply the actuating force to the actuating element pneumatically, hydraulically, mechanically, electrically, and / or magnetically. When the actuating force is applied pneumatically or hydraulically, the actuating element is preferably in contact with a piston-cylinder arrangement, or the actuating element is designed as a piston that closes a pressure chamber of a cylinder. This allows the actuating element to be subjected to a compressive force as the actuating force. When applied electrically or magnetically, corresponding elements are provided that generate the actuating force from an electric or magnetic field. Examples of suitable applications include electric motors, in particular linear motors or electric motors with recirculating ball screws. Alternatively, mechanical application, for example, by means of a rod assembly in contact with the actuating element, is also possible.

[0037] In order to apply the actuating force to the actuating element, a ball screw, a shift gate or shift drum or a cam can generally be provided.

[0038] Preferably, a clamping element is provided between the actuating element and the transmission element, preferably on the at least one clamping element, which is designed to generate an initial clamping contact force designed to improve the clamping for transmitting the actuating force. Preferably, the clamping contact force presses the part of the clamping element that is in contact with the transmission element to form the clamping onto the transmission element.

[0039] The clamping element is preferably designed as a spring element that generates the clamping contact force. The spring element is further preferably designed as a closed element, in particular as a ring, and is designed to apply the clamping contact force across the entire circumference between the transmission element and the actuating element.

[0040] Between the at least one clamping element and the transmission element, a friction element and a counter surface are provided, which are configured such that when the actuating force is applied to the actuating element, a reinforcing contact pressure acts between the friction element and the counter surface, which forms the clamping.

[0041] The counter surfaces and / or the friction element can preferably be designed with an increased coefficient of friction, particularly at the points where they are in contact with each other, in order to improve the transmission of the actuating force.

[0042] The counter surface is formed as a surface of a groove that extends along the actuation direction. The counter surface can, for example, be a surface at the bottom of the groove or the flanks of the groove transverse to the actuation direction. The friction element is designed as a spring that is designed to be guided in the groove along the actuation direction.

[0043] Preferably, the groove is designed as a groove that tapers transversely to the actuation direction, with the counter surface and another counter surface extending along the actuation direction forming the taper. Thus, in this groove design, the two counter surfaces are not oriented parallel to each other.

[0044] Preferably, the friction element is provided on the clamping element and the counter surface is provided on the transmission element, or preferably the friction element is provided on the transmission element and the counter surface is provided on the clamping element.

[0045] Preferably, in the end position of the clamping element, preferably at the stop, a lifting geometry is provided, which is designed to space the friction element from the counter surface, or at least to reduce the reinforcing contact pressure between the friction element and the counter surface. Such a lifting geometry can, for example, be a surface that rises counter to the actuation direction, wherein the friction element and the surface are configured such that the friction element is spaced from the counter surface upon contact with the surface, or such that at least the contact between the friction element and the counter surface is relieved such that the clamping is released.

[0046] According to the invention, a clutch actuator is further provided which has an actuating mechanism as described above, wherein the clutch actuator is designed to disengage a clutch with the transmission element, and wherein the transmission element is subjected to an elastic preload force in the actuating direction, which is preferably generated by a spring element, wherein the elastic preload force is designed in such a way that, when no actuating force is applied to the actuating element, it is in equilibrium with an elastic preload force of a clutch spring.

[0047] A clutch actuator designed in this way allows for reliable clutch disengagement, while also compensating for wear on the clutch when the clutch is engaged. It features self-aligning clamping elements, which significantly reduces the susceptibility of the clamping elements to breakage compared to a clutch actuator with permanently mounted clamping elements.

[0048] The embodiments described so far can be combined with one another as desired to obtain further embodiments that also comprise objects corresponding to the objects of the invention. Therefore, preferred embodiments of the invention are described below with reference to the accompanying drawings.

[0049] In detail, Fig. 1 a basic sectional view of an actuating mechanism according to the invention, Fig. 2 a detailed view of a possible design of the connection between the clamping element and the transmission element, Fig. 3 another detailed view of the connection Fig. 2, and Fig. 4 an inventive arrangement of the clamping elements in which high transverse forces in the clamping elements are avoided.

[0050] Fig. Figure 1 shows a sectional view of an actuating mechanism according to the invention. Since this sectional view is symmetrical about a horizontal axis 8 in the figure, only the elements of the actuating mechanism above axis 8 are described with reference numerals. The lower elements correspond to the upper elements, so no reference numerals are necessary here.

[0051] An actuating mechanism 9 is shown, which has a transmission element 1 in the form of a cylindrical rod, which extends from left to right in the illustration shown and has the axis 8 as the rod axis. The transmission element 1 is designed to be displaceable in an actuating direction X along the axis 8.

[0052] Instead of a cylindrical transmission element 1, other cross-sectional shapes are also conceivable. For example, a square or rectangular cross-sectional shape is also conceivable.

[0053] The transmission element 1 can also be hollow along the axis 8 in order to guide, for example, a shaft which is connected to a coupling.

[0054] Furthermore, an actuating element 6 is shown in section, which extends rotationally symmetrically around the axis 8 and around the transmission element 1. The actuating element 6 is designed to be actuated with an actuating force F B, which is shown on the left side of the actuating element 6. On the right side of the actuating element 6, the actuating element 6 abuts a clamping element 2. For this purpose, the actuating element 6 has a transmission surface 6a which is designed to come into contact with the clamping element 2. The clamping element 2 is arranged behind the actuating element 6 in the actuating direction X and is oriented so as to bend towards the actuating direction X. The transmission surface 6a is oriented perpendicular to the actuating direction X or to the axis 8.

[0055] The clamping element 2 extends from the actuating element 6 to the transmission element 1. Its free end contacts the surface 5 of the transmission element to form a clamp. Alternatively, another connection can be provided at this point, which can be made by means of the Fig. 2 and Fig. 3 is described in more detail.

[0056] The free end of the clamping element 2 is designed here as a clamping element receptacle 7. A clamping element 4, for example, in the form of an annular spring, is provided in the clamping element receptacle 7, which is designed, for example, as a groove surrounding the axis 8. The clamping element receptacle 7 and the clamping element 4 are not mandatory. In the embodiment shown, this supports the formation of the initial clamp, as described further below.

[0057] The clamping element 4 is designed here as an annular spring element, which extends rotationally symmetrically around the axis 8 of the transmission element 1. The clamping element 4 is designed such that, in the illustration shown, it is widened away from the axis 8 by the clamping element receptacle 7. As a result, the clamping element 4 exerts a clamping force F Sfrom the outside onto the clamping element holder 7, whereby the clamping element 2 is pressed onto the surface 5 of the transmission element 1.

[0058] In the embodiment shown, additional clamping elements 2 are arranged around the axis 8. Another is shown here in section below the axis 8.

[0059] Furthermore, a stop 3 is shown, which is stationary relative to the other elements, in particular relative to the actuating element 6 and relative to the transmission element 1.

[0060] The clamping elements 2 are further in contact with a return spring 10, which is only indicated schematically here. The return spring 10 is supported against the clamping elements 2 at a fixed point, for example, on a housing. The return spring 10 is designed to apply an elastic preload force to the clamping elements 2 opposite to the actuation direction X. If no actuation force F Bacts on the actuating element 6, the return spring 10 causes the clamping elements 2 to be moved back to the stop 3.

[0061] In the illustration shown, which corresponds to an end position of the clamping element 2 opposite to the actuation direction X, the clamping element 2 rests against the stop 3. As a result, the clamping element 2 is subjected to a reaction force which causes the clamping element 2 to be bent away from the axis 8. This occurs because the reaction force is oriented parallel to an actuation direction X, whereby a bending moment is created around the connection point between the actuation element 6 and the clamping element 2, which bends the clamping element 2 shown at the top of the illustration to the left and the clamping element 2 shown at the bottom to the right.

[0062] The operation of the actuating mechanism 9 is as follows.

[0063] If the actuating mechanism 9 is force-free, no actuating force F B applied to the actuating element 6, the transmission element 1 can move relative to the clamping elements 2 or relative to the actuating element 6 parallel to the actuating direction X. The clamping elements 2 are pressed against the stop 3 by the return spring 10 and, due to the reaction force with the stop 3, are either not in contact with the surface 5 of the transmission element 1 at all or only in such a way that a relative movement of the transmission element 1 is not hindered.

[0064] If an actuating force F B applied to the actuating element 6 in the actuating direction X, the actuating element 6 transmits the actuating force to the clamping elements 2 via the transmission surface 6a.

[0065] Due to their bending design, the clamping elements 2 are actuated by the actuating force F Bloaded so that it is perpendicular to the actuation direction X or perpendicular to the axis 8 on the surface 5 of the transmission element 1 with a supporting force F A This supporting force F A becomes so large due to the bending geometry of the clamping elements 2 that a clamping action is formed between the clamping elements 2 and the transmission element 1. This supporting force F A is proportional to the applied actuating force F B . The clamping corresponds to a frictional connection between the clamping elements 2 and the transmission element 1, via which a frictional force F prevailing here R the actuating force F B can be transferred to the transmission element 1. Thus, by this clamping, the actuating element 6, the clamping elements 2 and the transmission element 1 are locked together in the actuating direction X, so that they can be actuated by the actuating force F Bcan be moved in the direction of actuation.

[0066] By appropriately designing the clamping element 2, in particular its bending and / or its elasticity, and / or by appropriately designing the contact between the clamping element 2 and the surface 5, a maximum actuating force, i.e. an actuating force F B , which can be transmitted from the actuating element 6 to the transmission element 1. If the maximum actuating force is determined by the actuating force F B is exceeded, the transmission element 1 may begin to slip relative to the clamping element 2 or relative to the actuating element 6. However, this may also be desired as overload protection.

[0067] If the actuating force F Bagain away from the actuating element 6, the elastic preload force of the return spring 10 acts on the clamping elements 2, so that they are moved back together with the actuating element 6 against the actuating direction X into the end position shown.

[0068] At the latest when the clamping elements 2 rest against the stop 3 again, the resulting reaction force causes the clamping between the transmission element 1 and the clamping elements 2 to release, if this has not already happened when the actuating force F is removed. B has taken place.

[0069] The optional clamping element 4 also introduces an additional clamping force F into the contact between the clamping elements 2 and the transmission element 1. S introduced, which in addition to the supporting force F Aacts and thereby applies a force to the contact even when the actuating mechanism 9 is force-free, in order to keep the clamping elements 2 in contact with the transmission element 1, in particular with its surface 5, in this state and to clamp the element when the actuating force F is applied. B on the actuating element 6. The support of the supporting force F A by the clamping force F S is shown in the drawing by the relationship F A + F S clarified.

[0070] The clamping force F S can be calculated by designing the spring constant of the clamping element 4 and the expected expansion by the clamping elements 2.

[0071] The clamping element 4 therefore leads to the fact that the contact force between the clamping elements 2 and the transmission element 1 can be further increased, whereby the frictional connection, i.e. the clamping, between the transmission element 1 and the clamping element 2 is further strengthened, and the risk of slipping when an actuating force F is applied B can be reduced.

[0072] In addition, the actuating mechanism 9 shown can have an automatic wear adjustment, which is active when the clamping elements 2 rest against the stop 3 due to the elastic preload force of the return spring 10. As described above, the reaction force between the stop 3 and the clamping element 2 causes a bending moment to act on the clamping element 2, which urges the clamping element 2 in a direction away from the axis 8. The elements involved are designed in such a way that the contact between the clamping element 2 and the transmission element 1 is released. This reduces the maximum actuating force between the transmission element 1 and the actuating element 6, so that a displacement of the transmission element 1 relative to the actuating element 6 can be achieved even by small forces introduced into the transmission element 1 from the outside counter to the actuation direction X.

[0073] Such an externally introduced force can be introduced into the transmission element 1, for example, by a clutch spring. In this case, the transmission element 1 is designed to contact, for example, a release bearing of the clutch, with the clutch force being introduced into the transmission element 1 via the release bearing. To compensate for wear, the transmission element 1 is subjected to an elastic preload force in the actuation direction X. This is applied to the transmission element 1, for example, by a compensating spring 11.

[0074] If, for example, the clutch linings are heavily worn, this wear must be compensated. This is achieved by the clutch spring pressing more strongly on the transmission element 1. Since, in the end position shown, as described above, the maximum actuating force between the clamping elements 2 and the transmission element 1 is greatly reduced, and in a preferred embodiment can preferably be reduced to zero, the transmission element 1 can now move freely relative to the clamping elements 2 and thereby compensate for the clutch wear through the elastic preload force of the compensating spring 11. When an actuating force F BThe clamping is reestablished as described above. This occurs at the latest when the clamping element 2 releases from the stop 3. In preferred embodiments, however, this can also occur earlier. The permanently acting elastic preload force in the actuation direction X thus ensures continuous readjustment.

[0075] The contact between the clamping elements 2 and the transmission element 1 can, unlike previously described, also be designed in a different way to ensure secure clamping. Therefore, in the following Fig. 2 and Fig. 3 describes a possible design of the contact between clamping element 2 and transmission element 1. This contact can also be used in an actuating mechanism 9 according to Fig. 1 should be provided.

[0076] Fig. 2 shows a transmission element 1 and a clamping element 2 in the actuation direction X in section. Fig. 3 shows the same arrangement in section as Fig. 2 rotated 90°.

[0077] For reasons of clarity, Fig. 2 and Fig. 3 only one clamping element 2 is shown in a schematic diagram. The structure of the contact shown can be applied to other clamping elements 2, such as the one shown in Fig. 1 below. Furthermore, the description of the Fig. 2 and Fig. 3 refers to elements contained in Fig. 1 are shown.

[0078] The transmission element 1 has a groove tapering from the surface 5 of the transmission element 1 into the transmission element 1, which, as shown in Fig. 2, has two counter surfaces 1a, 1b. These counter surfaces 1a, 1b extend along the actuation direction X. The counter surfaces 1a, 1b are not oriented parallel, but rather form a tapered cross-section of the groove, with the groove having the largest opening on the surface 5 of the transmission element 1.

[0079] The clamping element 2 has a friction element 2a in the form of a spring at its free end. This spring is configured to correspond to the counter surfaces 1a, 1b of the groove so that it can be guided in the tapered groove in the actuation direction X. The friction element 2a and the groove with the counter surfaces 1a, 1b thus form a tongue-and-groove arrangement.

[0080] The functionality of the contact shown is as explained below.

[0081] In order to use the actuating force F BTo achieve a displacement of the transmission element 1 in the actuation direction X, the actuation force F B to the transmission element 1. This is also done by means of clamping, which is achieved here by a frictional connection between the friction element 2a and the counter surfaces 1a, 1b in response to the application of the actuating force F B trained.

[0082] If an actuating force F B applied to the actuating element 6, the clamping element 2 is released from the stop 3. This eliminates the reaction force between the clamping element 2 and the stop 3, whereby the actuating force F Bmust be supported by the clamping element 2, which now stands freely on the transmission element 1. This support occurs between the friction element 2a and the counter surfaces 1a, 1b, which thereby come into contact with each other or, if already in contact, are pressed more tightly against each other. To achieve the best possible clamping effect, the clamping element 2 does not come into contact with the surface 5 of the transmission element 1.

[0083] Due to the angled arrangement of the clamping element 2, as shown Fig. 1, a high support force F A in the clamping element 2 to support the actuating force F B . This supporting force F A is proportional to the applied actuating force F B and exerts a pressing force between the friction element 2a and the counter surfaces 1a, 1b. The ratio of the magnitudes of the actuating force F B and the supporting force F Acan be influenced in particular by the geometry of the clamping element 2, as described above.

[0084] The supporting force F A calls between the friction element 2a and the counter surfaces 1a, 1b reinforcement contact forces F V , which are each oriented perpendicular to the mating surfaces 1a, 1b. The magnitudes of the reinforcement contact forces F V are due to the inclination of the counter surfaces 1a, 1b in relation to the supporting force F A relatively high, since the inclination is designed in such a way that only a small part of the respective reinforcement contact force F V the supporting force F A The ratio of the supporting force F A to the reinforcement contact forces F V can be influenced constructively by the tapering of the groove, i.e. by an angle of inclination of the counter surfaces 1a, 1b.

[0085] This reinforcement contact force F Vforms the clamping in the form of a frictional connection for transmitting the actuating force F B on the transmission element 1. This also results in a higher maximum actuation force, which can be transmitted between the friction element 2a and the counter surfaces 1a, 1b, compared to the embodiment of Fig. 1. Thus, the generation of the reinforcement contact force F V that the displacement of the transmission element 1 in the actuation direction X can take place as soon as the resulting maximum actuation force is greater than or equal to the applied actuation force F B is.

[0086] The counter surfaces 1a, 1b and / or the friction element 2a can furthermore be designed with an increased coefficient of friction, in particular at the points where they are in contact with each other.

[0087] The transmission element 1 consequently experiences a displacement in the actuation direction X, which results from the actuation force FB is caused.

[0088] Nevertheless, the connection shown between the friction element 2a and the counter surfaces 1a, 1b also has a maximum actuating force, whereby an overload protection is realized, which, for example, allows the transmission element 1 to slip relative to the actuating element 6 if an excessive counterforce is introduced into the transmission element 1 and thus into the actuating mechanism against the actuating direction X.

[0089] Before the specific design of the clamping elements 2 is discussed, further embodiments of the invention will be described at this point.

[0090] In addition to a clamping element 4, Fig. 1, other clamping elements are also conceivable, which also allow the application of a clamping force F SFor example, instead of a spring element, a clamp can be used, which allows adjustment of the clamping force F S for example by means of a screw.

[0091] Since the clamping element 4 can optionally be added to improve the frictional engagement, embodiments are also conceivable which have neither the clamping element 4 nor the clamping element holder 7.

[0092] The actuating mechanism shown is, as described above, preferably suitable for use in a clutch actuator. The principle of transmitting the actuating force F Bfrom the actuating element 6 to the transmission element 1 can be used for both centrally and decentrally arranged clutch actuators. A centrally arranged clutch actuator is, for example, arranged relative to a clutch in such a way that the displacement of the transmission element 1 in the actuating direction X occurs centrally in alignment with the release bearing of the clutch. The displacement to disengage the clutch occurs here directly through the transmission element 1. In the case of a decentralized clutch actuator, the transmission element 1 is not arranged centrally in alignment with the release bearing in the actuating direction X. The displacement to disengage the clutch occurs here indirectly, for example through a transmission rod. Furthermore, in the case of a centrally arranged clutch actuator, a shaft which is connected to one side of the clutch can be guided through the clutch actuator.For example, the axis of this shaft corresponds to the axis 8 of the transmission element 1, whereby the transmission element 1 is hollow and the shaft penetrates the transmission element 1. However, these and other designs of clutch actuators do not limit the scope of the invention.

[0093] Does the actuating mechanism 9 Fig. 1 a contact between clamping element 2 and transmission element 1 as in the Fig. 2 and Fig. 3, the actuating mechanism 9 can also be designed to facilitate the release of the frictional engagement between the friction element 2a and the counter surfaces 1a, 1b. For example, a run-on bevel (not shown) can be provided, against which, for example, the clamping element 2 or the friction element 2a runs when it approaches the end position. The run-on bevel lifts the friction element 2a out of the groove or at least increases the reinforcing contact force F Vreduced. The starting bevel can be provided, for example, on stop 3.

[0094] When forming the clamping between the clamping element 2 and the transmission element 1, a transverse force in the circumferential direction around the actuation direction X or around the axis 8 can be introduced into the clamping elements 2 due to manufacturing tolerances. In particular, the formation of a contact, as shown in the Fig. 2 and Fig. 3 is prone to this problem. Therefore, a special arrangement of the clamping elements 2 was chosen to solve this problem.

[0095] Fig. 4 shows an arrangement of the clamping elements according to the invention in which high transverse forces in the clamping elements are avoided.

[0096] Eight clamping elements 2 are shown, which are arranged on a circle around the actuating direction X and which are regularly spaced in a circumferential direction Y oriented around the actuating direction X.

[0097] The arrangement of the clamping elements 2 forms an opening arranged concentrically to the actuation direction X, through which a transmission element, as shown in the Fig. 1 to 3 described.

[0098] The clamping elements 2 are shown opposite to the actuation direction X.

[0099] The clamping elements 2 are shown here as eight individual elements that are not connected to an actuating element. This design of the clamping elements 2 has the following advantage.

[0100] If an actuating force is applied to the clamping elements 2 from behind, for example by the actuating element 6 from Fig. 1, it may happen due to manufacturing tolerances that transverse forces in the circumferential direction Y are introduced into the clamping elements 2 in contact with the transmission element 1. If the clamping elements 2 were connected to each other, for example in a one-piece design together with the actuating element 6 from Fig. 1, this would lead to high tensions within the clamping elements 2, which would ultimately also result in the risk of the clamping elements 2 breaking.

[0101] The design of the clamping elements 2 proposed here addresses this problem by designing all clamping elements 2 separately and thus also allowing them to move relative to one another in the circumferential direction Y. Thus, the clamping elements 2 can align themselves accordingly in the circumferential direction Y when clamping is formed, so that no transverse forces occur in the clamping elements 2. LIST OF REFERENCE SYMBOLS 1 transmission element 1a Counter surface 1b Counter surface 2 clamping element 2a Friction element 3 stop 4 clamping element 5 Surface transmission element 6 Actuating element 6a Transfer surface 7 Clamping element holder 8 axis 9 Operating mechanism 10 Return spring 11 Compensating spring F A Supporting force F B Actuating force F R Frictional force F S Clamping force F V Reinforcement contact force X Actuating direction

Claims

[1] Actuating mechanism (9) for a clutch actuator, comprising: - an actuating element (6) which is designed to be actuated with an actuating force (F B ) and to be moved by it in an actuating direction (X), - a transmission element (1) designed to perform a displacement parallel to the actuating direction (X), - at least one clamping element (2) which is designed to clamp when the actuating element (6) is subjected to the actuating force (F B ), by forming a clamp, a transmission of the actuating force (F B ) to the transmission element (1), wherein the actuating element (6) and the at least one clamping element (2) are designed to be movable relative to one another in a circumferential direction (Y) which is oriented around the actuating direction (X), wherein between the at least one clamping element (2) and the transmission element (1) a friction element (2a) and a counter surface (1a) are provided, which are configured such that upon application of the actuating force (F B ) on the actuating element (6) between the friction element (2a) and the counter surface (1a) a reinforcing contact force (F V ) which forms the clamp, whereby the counter surface (1a) is designed as a surface of a groove which extends along the actuating direction (X), and the friction element (2a) is designed as a spring which is designed to be guided in the groove along the actuating direction (X). [2] Actuating mechanism (9) according to claim 1, wherein the actuating element (6) and the at least one clamping element (2) are designed to be movable relative to one another in the circumferential direction (Y) when the clamping is not yet fully formed and / or when the clamping is fully formed. [3] Actuating mechanism (9) according to one of the preceding claims, wherein the actuating force (F B ) in the actuating direction (X) from the actuating element (6) to the at least one clamping element (2) directly or via intermediate elements, wherein the actuating element (6) has a transmission surface (6a) which is used to transmit the actuating force (F B ) on which at least one clamping element (2) or on an intermediate element. [4] Actuating mechanism (9) according to claim 3, wherein the transmission surface (6a) is oriented perpendicular to the actuating direction (X). [5] Actuating mechanism (9) according to one of the preceding claims, wherein the actuating element (6) and the at least one clamping element (2) are arranged at least when the actuating element (6) is subjected to the actuating force (F B ) are in contact with each other directly or via at least one intermediate element. [6] Actuating mechanism (9) according to claim 5, wherein a rolling body is provided as at least one intermediate element. [7] Actuating mechanism (9) according to one of the preceding claims, wherein the at least one clamping element (2) is elastic. [8] Actuating mechanism (9) according to one of the preceding claims, wherein the actuating element (6) is designed to displace the at least one clamping element (2) counter to the actuating direction (X) at least over a part of the entire displacement during a displacement counter to the actuating direction (X). [9] Actuating mechanism (9) according to one of the preceding claims, wherein the actuating mechanism (9) is designed to release the clamping when no actuating force (F S ) is applied to the actuating element (6), and / or when the actuating element (6) or the at least one clamping element (2) is in an end position to enable a relative movement of the transmission element (1) with respect to the actuating element (6). [10] Actuating mechanism (9) according to claim 9, wherein the end position is defined by a stop (3) which is stationary relative to the transmission element (1), the at least one clamping element (2) and / or the actuating element (6). [11] Actuating mechanism (9) according to claim 10, wherein the at least one clamping element (2) is designed to bear against the stop (3) in its end position, and a force acts between the stop (3) and the at least one clamping element (2) which causes the clamping to be released. [12] Actuating mechanism (9) according to one of the preceding claims, wherein the actuating mechanism is designed to determine the actuating force (F B ) pneumatically, hydraulically, mechanically, electrically and / or magnetically to the actuating element (6). [13] Actuating mechanism (9) according to one of the preceding claims, wherein a clamping element (4) is provided between the actuating element (6) and the transmission element (1), which is designed to apply an initial clamping contact force (F S ) which is designed to clamp the actuating force (F S ) improved and the spring element is closed, in particular designed as a ring, and is designed to apply the clamping contact force (Fs) completely between the transmission element (1) and the actuating element (6). [14] Actuating mechanism (9) according to one of the preceding claims, wherein the groove is designed as a groove tapering transversely to the actuating direction (X), wherein the counter surface (1a) and a further counter surface (1b) extending along the actuating direction (X) form the taper. [15] Actuating mechanism (9) according to one of the preceding claims, wherein in the end position a lifting geometry is provided which is designed to space the friction element (2a) from the counter surface (1a), or at least the reinforcing contact pressure force (F V ) between the friction element (2a) and the counter surface (1a). [16] Clutch actuator, comprising an actuating mechanism (9) according to one of claims 1 to 15, wherein the clutch actuator (9) is designed to disengage a clutch with the transmission element (1), and wherein the transmission element (1) is subjected to an elastic preload force in the actuating direction (X), whereby the elastic preload force is designed in such a way that, if no actuating force (F B ) is applied to the actuating element (6), is in equilibrium with an elastic preload force of a clutch spring.

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