WO2011138225A1

WO2011138225A1 - Locking device for locking a motor vehicle part which is displaceable with respect to a motor vehicle structure

Info

Publication number: WO2011138225A1
Application number: PCT/EP2011/056748
Authority: WO
Inventors: Sebastian Heinze; Matthias Fischer; Alwin Macht
Original assignee: Brose Fahrzeugteile Gmbh & Co. Kg, Coburg
Priority date: 2010-05-03
Filing date: 2011-04-28
Publication date: 2011-11-10
Also published as: DE102010028513A1

Abstract

The invention relates to a locking device for locking a motor vehicle part (H, S) which is displaceable with respect to a motor vehicle structure (K) and can be locked in a respective inoperative position, which is reached by displacement, in a displacement region by means of the locking device, with - at least one first friction element (1) of the locking device, which friction element has a first friction surface (10), and - at least one second friction element (2, 2', 2'') of the locking device, which friction element has a second friction surface (20) and the second friction surface (20) thereof can be brought, in order to lock the motor vehicle part (H, S), into contact with the first friction surface (10) of the first friction element (1) in such a manner that the second friction surface (20) bears against the first friction surface (10) under static friction conditions, wherein the second friction element (2, 2', 2'') comprises a supporting structure (22, 8, 8*) via which the second friction element (2, 2', 2'') is mounted in the locking device, and at least one contact region (211, 211', 21.0) which is connected to the supporting structure (22, 8, 8*) and has at least one part of the second friction surface (20). According to the invention, the contact region (211, 211', 21.0) having at least one part of the second friction surface (20) is elastically supported at least in sections on the supporting structure (22, 8, 8*) supporting the second friction element (2, 2', 2'') in the locking device. By this means, the contact region (211, 211', 21.0) can be moved at least in sections in the direction of the supporting structure (22, 8, 8*) when the second friction element (2, 2', 2'') is brought with the second friction surface (20) thereof into contact with the first friction surface of the first friction element (1), i.e. the second friction surface (20) bears against the first friction surface (10) under static friction conditions.

Description

Locking device for locking a movable with respect to a motor vehicle structure motor vehicle part

description

The invention relates to a locking device for locking a movable with respect to a motor vehicle structure motor vehicle part, which is locked by the locking device in a displacement area (continuously) in a respective achieved by displacement rest position, according to the preamble of claim 1.

Such a locking device comprises at least a first friction element having a first friction surface, and at least one second friction element having a second friction surface and the second friction surface for locking the motor vehicle part in contact with the first friction surface of the first friction element can be brought that the second Friction surface under static friction conditions on the first friction surface is applied.

Here, the second friction element is usually adjustably mounted in the locking device, so that it is movable relative to the first friction element to allow a displacement of the motor vehicle part. At the end of a displacement movement of the motor vehicle part, the second friction element is automatically brought into contact with the first friction element, for example under the influence of a spring force, under static friction conditions. Thus, while in such a locking device during a displacement of the motor vehicle part, the second friction element with its friction surface (especially under Gleitreibungsbedingungen) along the friction surface of the first friction element can slide, the second friction element is in a rest position of the displaced motor vehicle part its frictional surface under static friction conditions frictionally on the friction surface of the first friction element.

A generic locking device is z. B. from WO 2009/007400 A1.

The motor vehicle part that can be locked with such a locking device may be, for example, a motor vehicle door (side or rear door) or a closure flap (front or tailgate) of a motor vehicle, which can be folded away from a motor vehicle structure, e.g. in order to allow access to the vehicle interior in the case of a motor vehicle door or, in the case of a closure flap, to allow access to the vehicle engine or a luggage compartment. In this case, it may be desirable for the corresponding motor vehicle part not to be folded down to its maximum possible pivoting position, but to make only a limited folding into a partially folded-down position with a smaller folding angle compared to the completely folded-down position. Here it is then to be provided that corresponding motor vehicle part can be locked in the partially folded-down position so that it is not already folded down by a gust of wind or by unintentional contact. In order to be able to frictionally connect the second friction element to the first friction element and, on the other hand, to release such a frictional engagement in order to be able to displace (further) the motor vehicle part from a rest position, the second friction element is mounted adjustably in the locking device relative to the first friction element.

This bearing takes place via a support structure of the second friction element, to which the friction element is connected (non-rotatably) to a force transmission means in order to transfer a force for releasing the frictional engagement on the second friction element during a displacement of the motor vehicle part from a rest position and second friction element to a movement to drive relative to the first friction element. Such a power transmission means is usually a shaft with which the second friction element is rotatably connected.

It has now been found that in conventional locking devices under certain circumstances, an undesirable jamming of the first and second friction element can occur if the frictional engagement on the two friction surfaces to be solved again. A jamming of the two friction elements occurs in particular then increasingly, If the two friction elements have different temperatures and / or are made of different materials having mutually different thermal expansion coefficients. Thus, it may happen that, for example, the second friction element has expanded or expanded at an elevated temperature more strongly in the direction of the first friction element and thus a built-frictional engagement is enhanced in a rest position of the motor vehicle part. The second friction element thus presses with at least slightly increased force on the first friction surface of the first friction element, so that a release of the lock is possible only with increased effort (by a user).

In addition, a release of the so clamped in each other first and second friction often only be made under a sound audible to the user when the frictional engagement is suddenly released. However, such a "release noise" that accompanied by a displacement of the motor vehicle part from a rest position, for example, as an audible crack release the lock, but is undesirable and affects the ease of use.

The present invention is therefore based on the object to overcome the disadvantages mentioned above or at least reduce and to further improve a locking device of the type mentioned.

This object is achieved with a locking device according to claim 1.

In such a locking device, a contact region having at least part of the friction surface of the second friction element is elastically supported at least in sections on the support structure supporting the second friction element in the locking device, that is to say such a contact region is elastic at least in sections relative to the support structure. The contact region and the support structure thereby form components of the second friction element, which is preferably designed in the form of a friction disk.

In order to always ensure an easy-to-release frictional engagement between the friction surfaces even at different operating temperatures and thus possibly temperature-related (slightly) varying externa ßeren dimensions of the two friction, the friction surface of the second friction element having contact area according to the invention with respect to the associated support structure this Friction element at least partially elastic or at least partially supported elastically on the support structure.

As already explained above, such a support structure is the (comparatively rigid) component of the second friction element, via which the friction element is positioned in the locking device as intended and in particular is adjustably mounted relative to the first friction element. In preferred embodiments of the present invention takes place on the support structure, the (non-rotatable) connection of the second friction element to a shaft of the locking device, which is displaced in a displacement of the motor vehicle part and the second friction element entrains, so that the second friction element moves relative to the first friction element and (under sliding friction conditions) slides along the friction surface of the first friction element. Accordingly, the support structure of the second friction element forms, for example, a positive engagement region via which the second friction element is positively connected to a force transmission means (eg in the form of the aforesaid shaft) for applying a force to move the second friction element relative to the first friction element into the second friction element initiate when the motor vehicle part is to be moved from its rest position.

A contact region of the second friction element, which forms the friction surface of the second friction element, is connected to this support structure and in particular can be formed integrally with this support structure. In the (second) friction elements hitherto known from the prior art, a contact region is rigidly connected to the support structure so as to preferably provide a one-piece and inherently stiff friction element to be connected to a power transmission means. In contrast, in the present invention, a contact region is at least partially movable in the direction of the support structures when the second friction element is brought with its second friction surface in abutment with the first friction surface of the first friction element or was.

In this way, a temperature-induced change in the outer dimensions of the second friction element can be compensated by the elastic support of the contact area, so that in particular no increased normal force acts on the friction surfaces and thus significantly changes a frictional engagement by varying temperatures in an undesirable manner, in particular (with rising Temperatures) is increased excessively. Such a reliable and smooth release of a locking of the motor vehicle part on the locking device can be ensured even at different (and possibly increased) operating temperatures.

Such a construction of the second friction element according to the invention can be used in particular in locking devices already known from the prior art, in which the first and second friction elements are braced against each other and the friction surfaces of the friction elements extend at an angle, in particular conically, to the effective direction of the bias.

Regularly, in this case, the second friction element is spring-loaded stored in a brake housing. In this case, the brake housing defines a (first) friction surface via an inner wall and thus forms a first stationary friction element of such a locking device. The second friction element, which is adjustably mounted on one and above a shaft, is preferably designed as a conical friction disk and mounted inside the brake housing, which forms a first friction surface with an inner wall, which also tapers conically. To lock the second friction element is brought by the acting in the direction of its tapered end bias in contact with the brake housing, so that the conical friction surfaces abut each other frictionally. Here, the conical shape of the friction surfaces offers the advantage of spring force amplification, so that a reliable locking is facilitated.

However, in such an embodiment as well, the elastic support of the contact region with the (conical) friction surface can reduce the risk that, as a result of different thermal expansion of the two friction elements, a jamming effect occurs during a displacement of the motor vehicle part from the rest position. Thus, the contact area remains in the direction of the support structure, that is radially relative to the shaft on which the second friction element is rotatably mounted, adjustable, so there is under load elastically, so that a release of the frictional engagement continues to be easily possible even with changing temperature conditions is.

This is particularly advantageous since, in order to ensure good sliding properties, so that the second friction element can slide smoothly (and under sliding friction conditions) with a displacement of the motor vehicle part relative to and along the friction surface of the first friction element, preferably one steel friction surface and the other made of plastic. Suitable material pairings are for example, also refer to WO 2009/007400 A1. Since the two materials mentioned (steel / plastic) but have different coefficients of thermal expansion, it may just at elevated operating temperatures and without elastic support according to the invention of the contact area, which forms at least a portion of the second friction surface, occur - as described above - jamming occurs , The risk of such jamming can be reliably reduced or even eliminated with the construction according to the invention of the second friction element, even in the case of the mentioned material pairing of the first and second friction surfaces.

In preferred embodiments of the present invention, therefore, the contact area on the second friction element is less rigid than the support structure connected to the contact area, which serves to securely support and position the second friction element in the locking device and optionally within a housing of the locking device.

Depending on the embodiment of the locking device, the contact region is integrally formed (for example) on the support structure or positively connected to the support structure or integrally formed with the support structure.

In order to provide elasticity between the contact region and the support structure, in one embodiment it can be provided, in particular, to form at least one recess in a section of the friction element that connects the contact region to the support structure. A rigidity of this section is thereby reduced via at least one recess or a plurality of recesses and an elastic support of the contact region in the direction of the support structure is provided or supported. Thus, by providing a relative to the externa ßeren dimensions of the second friction element relatively large recess or by the provision of a plurality of recesses in a rigid material itself an elastic deformability of a component made of this material can be realized. Thus, for example, a plurality of individual small recesses in the form of apertures or holes in a rigid material can lead to the component formed therewith becoming elastic or at least more elastic than an identical component that is made of the same material in full form. The elasticity or, in other words, the elastic deformability of a component or a portion of a component can thus be achieved or improved in a targeted manner by the provision or the introduction of recesses, even if the component or the section consists only of one slightly elastic material is made. Thus, for example, in an made of polyoxymethylene (POM) component an elastic structure by introducing a plurality of recesses, in particular breakthroughs elasticity can be introduced.

In the present case, a recess or a plurality of recesses is thus formed between an elastically and / or elastically supported contact region and a stiffer, supporting support structure, such that a (elastic) deformability of a region bounding the recess is permitted or improved by the recess or recesses. Such a section is thus formed with at least one recess so that the recess and thus the adjacent area can change in shape (eg, the area can elastically deform into the recess) to allow movement of the contact area relative to the support structure ,

In this case, a ribbing or rib structure can be produced by a plurality of recesses in the section of the second friction element connecting the contact region with the support structure, so that the contact region is connected to the support structure via individual narrow webs or ribs, wherein these ribs and webs are configured and arranged are that they can deform elastically and thus an elastic support of the contact area is realized.

In one embodiment, the second friction element has a connecting portion, via which at least a portion of the contact region is elastically connected to the support structure. For this purpose, the connecting portion is in particular designed such that it connects at least the one portion of the contact region elastically with the support structure. This is realized in one embodiment in that the connecting portion is integrally formed with the support structure and the contact area and the contact area is formed in the elastic portion to be supported relatively thin. That is, at this section immediately adjacent to a recess of the connecting portion, so that this at least a portion of the friction surface of the second friction member having portion of the contact portion is elastically deformable into the recess. Such a recess of the connecting portion is thus in front of the friction surface of the contact region in the direction of the support structure on the second friction element, so that in a frictional engagement of the second friction element on the first Friction element and when acting on the contact region or its friction surface and increased as a result of a change in temperature normal force elastic deformation of this portion of the contact portion is allowed in the recess of the connecting portion inside.

With a recess, a defined weakening point is thus introduced into the connection formed by the connecting portion to the support structure, so that the rigidity of the connecting portion and / or the rigidity of the contact region (locally) is deliberately reduced. It is thus achieved an elastic compliance of at least a portion of the contact region on which a part of the second friction surface is formed. In contrast to the previously known variants of the prior art, no support of the contact region is thus realized here by a rigid connection to the (preferably central or central) support structure, in particular by a solid and rigid full form.

In alternative or additional embodiments of the locking device according to the invention, the second friction element is further made of at least two materials having different thermal expansion coefficients.

In this way, it can be achieved that, when the (operating) temperature within the locking device changes, components of the second friction element expand or contract to different degrees. The second friction element thus expands at a temperature increase, for example, not evenly in the direction of the first friction element, whereby an undesirable jamming could be caused, but partially different due to the different materials. Thus, for example, a material with a higher coefficient of thermal expansion is used only in the regions or sections of the second friction element, in which the use of this material appears to be functionally required. For example, the contact area with the friction surface may be made of a material having a higher thermal expansion coefficient than the material from which the support structure is made.

In one embodiment, the contact region with at least one part of the friction surface of the second friction element is made of a plastic in order to ensure the best possible sliding properties of the second friction element. The supporting and the friction element overlapping, for example, connecting with a shaft support structure is in turn made of a stiffer material such. As steel. there Steel has up to ten times lower thermal expansion coefficient than conventional plastics, so that a larger thermal expansion can be limited to a temperature increase only to a local part of the second friction element.

By such a contact area is now (additionally) supported elastically on the stiffer and the lower coefficient of thermal expansion having support structure, a temperature-induced increase in the frictional engagement and thus jamming of the two friction elements can be avoided even more reliable. This advantage is particularly apparent in comparison with a second friction element made entirely of a plastic material.

In one embodiment, the second friction element further comprises a plurality of individual spaced-apart segments, each forming a contact area with a portion of the friction surface. In this case, in one embodiment, in each case a segment is provided on a segment arm of the support structure, which protrudes from a support section of the support structure in the direction of the first friction surface.

In such an exemplary embodiment, the second friction element is designed substantially as a friction disk composed of a plurality of individual segments, in which the individual segments are each provided on a segment arm of the support structure that is projecting radially from a central support section. In this case, the storage of the second friction element and as described above z. B. the (non-rotatable) connection with a power transmission means of the locking device.

By providing individual (radially) spaced-apart segments on the second friction element can be achieved in particular that expand the individual segments independently and to different degrees as a result of an increase in temperature. Thus, the risk that the second friction element at a temperature increase at all segments clamped against the first friction element, after the rest position of the motor vehicle part was taken and locked, considerably reduced. Preferably, in such an embodiment, the support structure is formed by a metallic "insert" (here as an English term for an "insert") or a core, on whose projecting segment arms the individual segments each positively and / or non-positively connected or molded onto this. In this case, each of a contact region and thus a portion of the friction surface of the second friction element defining segments preferably have a lower coefficient of thermal expansion than the material from which the supporting structure defining metallic insert or core is made. In particular, an embodiment of the segments from POM is considered to be advantageous.

In a further development, it is further provided that a segment in each case has at least one recess, via which an elasticity of the segment is provided or increased. As already explained above, the contact area can thus be elastically formed or supported on a segment (so that the contact area acts on the (normal) force acting on the friction surface in the direction of the support structure - as in the case of an installation of the second Friction elements on the first friction element under static friction conditions and a temperature-induced expansion of the contact area in the direction of the (first) friction surface of the first friction element - is movable to avoid jamming of the two friction elements on this segment.

Preferably, the formation of the segment or a connecting portion between the contact area and the support structure is such that the elastic support of the contact area shows a degressive behavior, so initially the force required for movement of the contact area in the direction of the support structure increases sharply with increasing distance, but with further increasing movement towards the support structure decreases the force increase. Ideal for this is a plate spring-like design of adjacent to the contact area sections of the second friction element.

In particular, in a production of the first friction element z. B. in the form of a (brake) housing made of steel and the production of the contact area or the entire second friction element made of plastic, the greater extent of the contact area and the second friction element compared to the first friction element on the elastic support of the contact area recorded at a temperature increase be applied, even if the second friction element for locking the motor vehicle part under static friction conditions on the first friction element. A caused by the temperature increase normal force increase at the friction point at which the two friction surfaces abut each other is thus determined by a in the second friction element (by suitable shaping) introduced spring characteristic and not the modulus of elasticity and the size of the second friction element. Further advantages and features of the present invention will become apparent in the following description of exemplary embodiments with reference to the figures.

a perspective view of a side vehicle structure with an unfolded vehicle door; a perspective view of a rear of a motor vehicle with an unfolded flap in the form of a tailgate;

Figure 2 shows a first embodiment of an inventive

Locking device for a motor vehicle door in cross section;

FIGS. 3A-3B show various representations of a second friction element in the form of a friction disk known from the prior art; a first embodiment of a second friction element according to the invention, in which a contact region having a part of the friction surface of the second friction element is elastically supported in sections on a support structure via a rib structure;

Figure 5 is a plan view of a second embodiment of a second

Friction elements with alternative rib structure;

FIGS. 6A-6C show different representations of the second friction element from the figure

5;

Figures 7A - 7C are various illustrations of a third embodiment of a second friction element for the locking device of Figure 2 with a support structure in the form of a metallic insert, on which individual spaced-apart segments for defining each part of the friction surface of the second friction element are arranged; Figures 8A-8B show various views of an embodiment based on the embodiment of Figures 7A-7C. Figures 1 A and 1 B illustrate first with respect to a motor vehicle structure displaceable or deflectable motor vehicle parts which can be locked by means of a locking device according to the invention in a partially folded position and thus in a respective rest position achieved by displacement. FIG. 1A shows a detail of a lateral motor vehicle structure in the form of the body K of a motor vehicle which, together with a roof area D of the motor vehicle, defines and encloses a door opening O through which a passenger can enter the interior of the motor vehicle. For closing the door opening O a hinged side door S is provided as a displaceable motor vehicle part, which is shown in Figure 1 A in a partially folded position. By means of a locking device, which is shown by way of example in the embodiment of Figure 2, the side door S can be locked in a partially unfolded or folded position so that they are not already on by a gust of wind or unintentional touching on the part of a passer on or folded , that is, relocated.

An intentional shift of the side door S, for example, to close or open them completely, should again be possible to use as user-friendly. In addition, a desired smoothness of the side door S should not be affected during a shift.

This object is achieved with a generic locking device, in which a (second) friction element during a displacement of the side door S (under sliding friction conditions) relative to another (first) friction element is movable and for locking the side door S in frictional contact with this (first) Friction element can be brought.

It should also be noted with reference to FIG. 1B that locking devices of the type mentioned can be provided not only for side doors of a motor vehicle, but also for a rear door or tailgate H provided on the rear side R of a motor vehicle and serving to close a loading space L. Further possible areas of use are trunk flaps, engine flaps, sliding doors, adjustable loading floors, roller blinds and other vehicle parts that are relative to a structural assembly of the motor vehicle are displaced (deflectable). In the following, it will be generally spoken of relocatable motor vehicle parts, wherein in particular pivotable (hinged) but also displaceable motor vehicle parts are to be included.

2 shows in a cross section an embodiment of a locking device according to the invention, by means of a displaceable motor vehicle part, such. B. a side door S according to the figure 1 A or a tailgate H according to the figure 1 B, in a partially folded position (infinitely) can be locked.

The locking device comprises a housing 5 with a housing lower part 51 and a housing upper part 52 which by suitable fastening means, for. B. in the form of screws or rivets, are fastened together. In the housing 5, two friction elements 1, 2 are arranged, the superimposed facing friction surfaces 10, 20 (frictionally) can be brought into engagement in order to lock by the thereby acting (static) static friction a displaceable motor vehicle part continuously in partially folded or deflected position ,

The first friction element 1 is formed by a portion of the inner wall of the housing 5. This section is part of the inner wall of the lower housing part 51 which is rotationally symmetrical with respect to a housing axis A and which defines or forms a friction surface 10 of the first friction element 1, which conically tapers toward the housing bottom of the housing lower part 51. Thus, the first friction element 1 is fixed to the housing by its with respect to the housing axis A rotationally symmetrical, conically tapered friction surface 10 forms an immediate part of an annular circumferential inner side wall of the housing 5.

Alternatively, a housing-fixed first friction element, for example, also be realized in that a separate from the inner wall of the housing 5 friction element is fixed in the interior of the housing.

The second friction element 2 is disc-shaped and rotatably mounted on a shaft 3, which is rotatably mounted at its two ends 31, 32 in each case an associated bearing 53 or 54 of the housing 5. In this case, the axis of rotation of the shaft 3 coincides with the housing axis A. The second friction element is thus attached as a separate component to the shaft 3 and stored in the housing 5 of the locking device as intended. For fixing the friction element 2 to the shaft 3, the friction element 2 forms a support structure in which a form-fitting region 25 is provided, which engages in a form-fitting region 35 of the shaft 3 in order to connect the friction element 2 in a rotationally fixed manner to the shaft 3. In the present case, this form-fit region 25 is a groove on a through-opening formed centrally in the friction element 2, through which the shaft 3 is partially guided. About the provided with a keyed form-fitting region 35 of the shaft 3 and this groove on the positive connection portion 25 of the friction element 2 is thus a positive shaft-hub connection between the friction element 2 and the shaft 3 realized, which axial mobility of the second friction element along the housing axis A. and thus allows the axis A of the shaft 3.

Of course, instead of the illustrated shaft-hub connection, an alternative connection between the friction element 2 and the shaft 3 would also be conceivable, which permits axial mobility of the friction element 2 along the (housing) axis A.

Spaced radially to the support structure with the form-fitting region 25, the friction element 2 forms one or more contact regions, which together define the conical friction surface 20 on the outer circumference of the friction element 2. This conical friction surface 20 is opposite to the conical friction surface 10 of the first friction element 1 and is frictionally engageable with this.

In order to frictionally engage the friction surfaces 10, 20 of the two friction elements 1, 2, an elastic element 4 in the form of a spring, more precisely in the form of a helical spring designed as a compression spring, is provided which surrounds the shaft 3 and which on the one hand on a widened end portion 32 of the shaft 3 and on the other hand on the second friction element 2 is supported. The support of the elastic element 4 in this case is such that it has the tendency to brace the second friction element 2 against the first friction element 1 and thereby bring the two friction surfaces 10, 20 with each other. In other words, a direction of action R, the forces applied by the prestressed elastic element 4 or bias such that it extends along the shaft 3 and along the axis A and the second friction element 2 along that direction R, against the first Frictional element 1 braced. Due to its axially displaceable mounting, the second friction element 2 can be tracked (automatically) under the action of the prestressing of the elastic element 4 in such a way that it can always be brought into engagement with the associated friction surface 10 of the first friction element 1. The tracking takes place automatically under the action of the bias of the elastic element 4 and taking advantage of the axial displaceability of the second friction element 2 along the shaft. 3

The material for the friction surfaces 10, 20 of the two friction elements 1, 2 is to be chosen so that the two friction surfaces 10, 20, when engaged with each other, generate a sufficiently large static stiction to partially by means of the locking device with respect to a motor vehicle structure deflected motor vehicle part in its partially deflected position. For example, for this purpose, the friction surface 10 made of steel and the friction surface 20 made of polyoxymethylene (POM). In addition to a reliable locking to the locking device as smooth as possible shifting of the corresponding motor vehicle part are made possible, so that the friction between the two friction surfaces 10, 20 of the friction elements 1, 2 acting friction forces at a relative movement of the two friction surfaces 10, 20 to each other as low as possible. The sliding friction acting between the two friction surfaces 10, 20 in a relative movement should thus be significantly less, if possible by a multiple lower than the (static) static friction acting between the two friction surfaces 10, 20, when the second friction element 2 in the rest position of the motor vehicle part is braced by the elastic element 4 against the first friction element 1. This is achieved, on the one hand, by the abovementioned or an alternative combination of materials for the friction surfaces 10, 20 (cf., in particular, WO 2009/007400 A1) and, on the other hand, by an optionally used (flowable) intermediate medium Z, during a movement of the second friction element 2 relative to the first friction element 1 between the mutually facing friction surfaces 10, 20 of the two friction elements 1, 2 is to bring and reduces the frictional forces acting.

Such an intermediate medium Z in the form of a lubricant is presently provided in the lower housing part 51, specifically with a filling height such that it reaches at least as far as the underside of the second friction element 2 facing the housing bottom.

The angled to the direction of action R of the bias extending friction surfaces 10, 20 offers the advantage of a spring force, so that a secure locking of the movable motor vehicle part is ensured by the locking device. But just at this angled, conical here, the course of the friction surfaces and the previously mentioned combination of different materials for the two friction surfaces 10, 20 but at different thermal expansion of the two friction elements 1, 2, a Verklemmeffekt occur upon first actuation after temperature rearrangement. Thus, it may happen in particular that the (operating) temperature within the housing 5 increases during the locking and thus when the two friction elements 1, 2 under static friction conditions. As a result, in particular, the friction elements 1, 2 expand. However, this leads to an increase of the force acting on the friction surfaces 10, 20 normal force, which is perpendicular to the friction surfaces 10, 20 runs. An increase in the normal force in turn causes an increase in the frictional engagement and thus possibly leads to a jamming of the two friction elements 1, 2. A release of the frictional engagement and thus a release of the locking by the locking device is thus possible only by a relation to normal operation increased release force and may be accompanied by an audible release sound.

In particular, in the exclusive use of a material for the second friction element 2 with a coefficient of thermal expansion which is significantly greater than a coefficient of thermal expansion for the material from which the fixed (first) friction element 1 is made, such jamming can occur more intensively. For example, the lower housing part 5 and thus the inner wall of the steel defined the friction element 1 and the second friction element 2 is made entirely of a plastic. With an increase in temperature, the friction element 2 thus expands more strongly and presses more strongly in the radial direction onto the friction element 1, as a result of which the frictionally engaged frictional connection could be undesirably (locally) reinforced.

Prior art embodiments of second friction elements 2 ^* for a locking device of FIG. 2 are shown in FIGS. 3A and 3B to illustrate the problem of jamming associated with thermal expansion. FIG. 3A is a sectional top view of a locking device with a first, fixed friction element 1 ^* and a second friction element 2 ^* that can be moved relative thereto and thus be brought into frictional engagement. FIG. 3B, in turn, shows a second friction element 2 ^* as a single component in a plan view, differences of an alternative embodiment of the friction surface 20 'of the second friction element 2 ^* and of a different dimensioning of the second friction element 2 ^{* being} owed to the illustration of FIG however, to change the basic operation. The friction element 2 ^* of Figure 3A is analogous to the friction element 2 of Figure 2 (and analogous to the friction elements shown in Figures 4 to 8B) substantially disc-shaped and mounted within a housing, on whose inner wall a friction element 2 ^* surrounding, flat Friction surface 10 ^{* is} formed. It is thus again defined a fixed, fixed to the housing first friction element 1 ^* , on which the second friction element 2 ^* can abut frictionally.

The friction surface 20 ^{* of} the second friction element 2 ^* is crowned so that the friction element 2 ^* can only be brought into engagement with the friction surface 10 ^{* of} the associated first friction element 1 ^* via part of its circumferential friction surface 20 ^* . Between convex, in the direction of the friction surface 10 ^{* of} the first friction element 1 ^* radially projecting, curved contact areas 21 1, each defining a part of the (total) friction surface 20 ^* are thus indented intermediate regions 212 on the peripheral side of the second friction element 2 ^* educated. These intermediate regions 212 lie opposite the first friction surface 10 ^* when the second friction element 2 ^* abuts on the first friction element 1 ^* at a distance, so that a cavity in the form of an intake region EB is formed between two contact regions 21 1 engaged with the friction surface 10 ^* is. With this movement region EB, the intermediate medium Z can move between the friction surfaces 10 ^* and 20 ^{* of} the two friction elements 1 ^* , 2 ^* relative to the first friction element 1 ^* when the second friction element 2 ^* moves, thereby correspondingly reducing the sliding friction.

The second friction element 2 ^* is formed in one piece, so that a support structure 22 of the second friction element 2 ^* , on which the positive engagement region 25 for supporting the second friction element 2 ^{* is} formed, together with the other components of the second friction element 2 ^* , in particular the contact regions 21st 1 and the intermediate regions 212. In order to be able to safely introduce the forces occurring at the contact areas 21 1 during the locking into the support structure 22 and thus the shaft 3, in the second friction element 2 ^* known from the prior art, a reinforcing, rigid connection section 23 ^{* is} in the form of a single Ridge or a single web provided, which extends like a spoke straight and radially to the axis A of the shaft 3, starting from the support structure 22 in each case to a contact region 21 1. Thus, a contact region 21 1 is rigidly supported on the central or central support structure 22 via the individual rib of a connection section 23 ^* , so that a on the part of the friction surface 20 ^{* of} the contact portion 21 1 introduced normal force F _{N is introduced} via the single rib of the connecting portion 23 ^* directly into the support structure 22. The thickness or thickness d of the single rib of the connecting portion 23 ^* is always chosen so that the contact portion 21 1 each as stiff as possible with the support structure 22, where the bearing on the shaft 3, connected and supported on this.

This basic principle can also be seen from the exemplary embodiment of FIG. 3B, in which a plurality of individual ribs or struts, such as spokes, run from a central, substantially circular support section 220 of a support structure 212 to the peripherally formed contact regions 212 ^* , in each case via a contact region 212 ^* single rib in a connecting portion 23 ^* as stiff as possible to connect to the support portion 220.

In contrast to the embodiment variant of FIG. 3A, the individual contact regions 212 ^* , on which the friction element 2 ^{* can} abut frictionally on the first friction element 1 ^* , are separated from one another by smaller intermediate regions 21 1 ^* . Thus, the intermediate regions 21 1 ^* in the form of small pockets or depressions in the conical peripheral surface of the second friction element 2 ^{* are} formed, so that the friction surface 20 ^{* over} this into several (present 5) individual sections is divided and the second friction element 2 ^* to the Intermediate areas 212 ^* can not abut the friction surface 10 ^{* of} the first friction element 1 ^* .

According to the invention, it is now provided that a contact region 21 1 of the movable, second friction element 2 is elastically supported, at least in sections, on the support structure 22 of the friction element 2, via which the second friction element 2 is mounted in a locking device. In this way, a contact region 21 1 of the second friction element 2, which has at least a portion of the friction surface 20 to be engaged with the friction surface 10 of the first friction element 1, can be at least partially movable in the direction of the (central) support structure 22, if the two friction elements 1, 2 abut each other under static friction conditions and as a result of an increase in temperature, the expanding second friction element 2 presses more strongly against the friction surface 10 of the first friction element 1.

In the embodiment of Figure 4, in which the locking device of Figure 2 is shown in a sectional plan view and in a sectional view along a section line AA, this is realized by an elastic support of a contact portion 21 1 via a respective elastic connecting portion 23. It is the Connecting portion 23 in the plan view formed substantially Y-shaped, so that at a contact portion 21 1 each two at a distance l ₆ mutually engaging force introduction ribs 23.2a and 23.2b engage the contact portion 21 1. These two force introduction ribs 23.2a, 23.2b open in the direction of the support structure 22 with the positive connection region 25 into a single base rib 23.1 of the connection section 23, which connects the two force introduction ribs 23.2a, 23.2b with the support structure 22 as the foot of the Y shape.

By thus spaced by a recess 6 force introduction ribs 23.2a, 23.2b is at least one central abutment portion 21 1 a of the thin-walled contact portion 21 1 (at least slightly) elastic. In this case, the individual (in FIG. 4 six) contact regions 21 1 of the friction element 2 are each crowned, so that they each represent, for example, a circular segment whose radius is smaller than a radius of a circular path along which the two contact regions are arranged one behind the other along the circumference are. Each contact area 21 1 thus has a central contact portion 21 1 a, which is flanked on both sides in the circumferential direction by an edge portion 21 1 b and on which the part of the friction surface 20 is formed, on which a frictional contact with the friction surface 10 of first friction elements 1 is produced. While the edge portions 21 1 b are supported by the two force introduction ribs 23.2a and 23.2b substantially radially and thus substantially perpendicular to the friction surface 20, adjacent to the contact portion 21 1 a in the direction of the support structure 22 directly to the recess 6. As a result, the thin-walled contact section 21 1 a can deform at least slightly elastically into the recess 6 in order to absorb a temperature-induced expansion of the friction element 2 and prevent a plane perpendicular to the friction surface 20 from contacting the contact region 21 1 or the contact section 21 1 a Normal force F _N leads to jamming.

The illustrated geometry of the connecting portion 23 thus reduces the rigidity of the contact region 21 1 or its support on the abutment portion 21 1 a, so that in this case an elastic deformation with a temperature increase is specifically permitted. The recess 6 serves to introduce a defined weakening point in the connecting region 21 connecting the contact region 21 1 to the support structure 22 in order to at least locally reduce the rigidity of the second friction element 2. The Y-shaped rib structure of the connecting portion 23 is further shown enlarged in the sectional view of Figure A, which results from the section line AA. Here it is also apparent that the recess 6 is formed as an opening, so that the connecting portion 23 is hollow in the region of the recess 6. In the case of a temperature-induced expansion of the integrally formed friction element 2, the contact section 21 1 a forming an inner surface 60 of the opening can yield elastically in the direction of an opposite inner surface 61 of the opening or the recess 6 in order to avoid jamming of the two friction elements 1, 2.

Thus, by way of the embodiment of the rib structure shown, an elastic, resilient support of the contact section 21 1 a of the contact region 21 1 is selectively provided without having to provide separate elastic elements on the second friction element 2 (further to the elastic element 4). Rather, the second friction element 2 may further integrally with the support structure 22, the plurality of connecting portions 23 and the friction surface 20 forming contact areas 21 1 z. B. be formed from a plastic material.

FIG. 5 illustrates a further exemplary embodiment of a second friction element 2 'in plan view, which can be used instead of the second friction element 2 of FIG. 2 in a locking device according to the invention and which is shown in further views in FIGS. 6A to 6C.

The disk-shaped friction element 2 'again has an inner support structure 22 on which the form-fit region 25 is formed centrally and which is surrounded by a circular support section 220 here. This circular, d. That is, support section 220 extending substantially along a circular path is connected to the form-fit region 25 via a plurality of spoke-shaped reinforcing ribs, so that the entire support structure 22 serving for supporting the friction element 2 'is stiffened and relatively rigid.

In each case in the radial direction, a plurality of individual (in the present case 5) elastic connecting sections 23 'adjoin to this rigid support structure 22, via which the support section 220 is connected in each case to a contact region 21 1'. Here, too, a contact region 21 1 'forms in each case a part of the peripherally extending friction surface 20 of the friction element 2', via which the friction element 2 'can be brought into engagement with the housing-fixed, first friction element 1, around a motor vehicle part (see FIG and 1 B) to lock in a rest position. The individual, along the circumference successive contact areas 21 1 'are each separated by intermediate regions 212' from each other. These intermediate regions 212 'are each connected to the support section 220 of the support structure 22 via a rigid connecting section 24 in the form of a radially extending spoke.

The contact regions 21 1 'and the intermediate regions 212' are formed in such a way that the contact regions 21 1 'protrude at least slightly further in the radial direction in the direction of the first friction element 1, so that the second friction element 2' extends exclusively over the contact regions 21 1 'and the friction surface 20 formed by them in engagement with the friction element 1 can be brought. For example, it can be seen in particular from FIGS. 6B and 6C that the individual contact regions 21 1 'are slightly more convex than the intermediate regions 212'. The intermediate regions 212 'are thus located opposite the contact regions 21 1' slightly in the direction of the support structure 22 on the friction element 2 'and are slightly flattened, so that between the intermediate regions 212' and the friction surface 10 of the first friction element 1 respectively a catchment area EB is formed for the penetration of intermediate medium Z.

The elastic support of each of the part of the Gesamtreibfläche 20 having contact portions 21 1 'on the rigid support structure 22 is realized in this embodiment via a specific embodiment of a rib structure in the connecting portion 23'. Thus, the connecting section 23 'has two force introduction ribs 23.2a' and 23.2b 'running essentially radially from a contact region 21 1' in the direction of the support structure 2. These two force introduction ribs 23.2a 'and 23.2b' are spaced from each other by a recess 6 here in the form of a substantially radially extending, narrow oblong hole. These two force introduction ribs 23.2a ', 23b' open into an integrally formed with them and extending transversely to them base rib 23.1 '. The base rib 23.1 'is in turn only connected to two spaced-apart webs 231 and 232 with the support portion 220 of the support structure 22.

The two webs 231 and 232 are spaced apart from one another by a further recess 7, which is essentially in the form of a further narrow elongated hole transverse to the extension direction of the recess 6 and the mutually parallel force introduction ribs 23.2a ', 23.2b' and substantially along a circular path the axis A of the shaft 3 extends when the second friction element 2 'is installed as intended in the locking device. Between the transverse base rib 23.1 ' Thus, a gap formed by the recess 7 gap to the support portion 220, which is bridged only by the two spaced apart webs 231 and 232.

A length \ _{7 of} the recess 7 along a circular path is selected such that the recess 7 extends completely along the section of the base rib 23.1 'along which the two force introduction ribs 23.2a' and 23.2b 'open into the base rib 23.1'. The recess 7 is thus in the extension direction of the two force introduction ribs 23.2a ', 23.2b' on the support structure 22 and the support portion 220 and extends - from the contact portion 21 1 'from - behind the base rib 23.1'. In this way, a defined weakening point in the connection between a contact region 21 1 'and the support portion 220 is introduced through the recess 7 in order to at least locally reduce the rigidity of the friction element 2' and the contact area 21 'elastically to the stiffer Support structure 22 support. Thus, the base rib 23.1 'can at least slightly bend at a normal force acting on it via the force introduction ribs 23.2a' and 23.2b 'in the direction of the support structure 22 and thus be elastically deformed into the recess 7 when the contact region 21 1' with its supported by the force introduction ribs 23.2a ', 23.2b' abutment portion 21 1 a 'due to an elevated temperature in the direction of the friction surface 10 of the first friction element 1 expands. At least the abutment portion 21 1 a 'of the contact portion 21 1 can thus move in the direction of the support structure 22 to compensate for a temperature-induced expansion and to avoid a temperature-induced increase in the frictional force.

By the stiffness of the connecting portions 23 'thus selectively reduced and the individual connecting portions 23', respectively adjacent pairs of force introduction ribs 23.2a ', 23.2b', further separated by larger cavities, in which the rigid connecting portions 24 a radial connection between the Providing intermediate regions 212 'and the support section 220, a friction ball of the friction element 2' defined by a contact region 21 1 'is thus elastic with respect to the stiffer support structure 22. A spring characteristic of the connecting portion 23 'is determined in particular by its geometry and the size of the recesses 6 and 7 (individually).

In the present case, the recesses 6 and 7 extend with substantially identical lengths l ₆ and l ₇ within the connecting portion 23 ', wherein a length l ₆ or I ₇ only a fraction of the circumference of the disc-shaped friction element 2' makes. In particular, with reference to FIGS. 6A and 6C, fastening webs 26 that are still substantially perpendicular to the support section 220 can also be seen. These can be used in the present case for fastening the elastic element 4 to the second friction element 2 '.

7A to 7C and 8A to 8B, in contrast to the preceding exemplary embodiments, a second friction element 2 "is produced from two different materials with mutually different coefficients of thermal expansion, wherein a support structure 8 or 8 ^* consists of a metallic material, in particular the friction surface 20 of the second friction element 2 "is made of a plastic material which has a larger thermal expansion coefficient relative to the material of the support structure 8, 8 ^* . The exemplary embodiment shown in various views in FIGS. 7A to 7C accordingly has a metallic insert or core as a support structure 8, which has segment arms 8.1 shaped in one piece with a central support section 8.2. The support section 8.2 has, analogously to the support section 220 of the preceding figures, a form-fit region 8.5, by means of which the second friction element 2 "of FIGS. 7A to 7C is to be fastened to the shaft 3 of FIG. 2 instead of the second friction element 2, around the second friction element 2 "in the locking device intended to store axially displaceable.

At the central support section 8.2 with the form-fit region 8.5, the (five) segment arms 8.1 are arranged radially and in a star-shaped projecting manner. At each of these segment arms 8.1, a segment 2.1 is arranged in each case from a plastic material, which is fixed in a form-fitting manner to the associated segment arm 8.1. In this case, a segment 2.1 may have been designed as a prefabricated component and subsequently attached to the segment arm 8.1 assigned to it, or a segment 2.1 has been injection-molded onto a segment arm 8.1 (for example by an injection molding process). In any case, a respective segment 2.1 is firmly connected to a segment arm 8.1 in the region of an end section 8.3 of the respective associated segment arm 8.1, which is spaced from the support section 8.2. Each of a conically tapered friction surface and a portion of the friction surface 20 at a contact portion 21 .0 forming segments 2.1 each have a base in the form of a circular segment. The individual segments 2.1 are Furthermore, each spaced apart in the circumferential direction, so that between them a gap with the width g is formed as a segment distance, on the relative to the first friction member 1 during a relative movement of the second friction element 2 ^** the intermediate medium Z to improve the sliding friction between the friction surfaces 10th , 20 can get.

Furthermore, the peripheral contact areas 21 .0 of the individual (spherical) segments 2.1 extend with the part of the friction surface 20 which can be brought into engagement with the friction surface 10 of the friction element 1, along a circular path whose radius is smaller than the radius of the circular path , along which the individual segments 2.1 are arranged one behind the other on the second friction element 2 ^** . Thus, the crowned or domed segments 2.1 lie against the friction surface 10 of the first friction element 1 only with a part of the contact region 21 .0, so that in the region of the gap between two adjacent segments 2.1 a retraction region EB is again defined, in which the second friction element 2 "along its circumference can not rest against the first friction element 1 (cf., in particular, FIG. 8B with an analogous design of the segments 2.1).

In addition to the use of materials with different thermal expansion coefficients for the support structure 8.2 of the friction element 2 "on the one hand and the individual segments 2.1 of the friction element 2" on the other hand is in the embodiment of Figures 7A to 7C to avoid unwanted jamming of the two friction elements 1, 2 "of the locking device at a temperature-induced expansion of the friction element 2 "also provided that the individual contact portions 21 .0 are each elastically supported on the associated segment of the arm 8 8.1 support structure. For this purpose, a plurality of recesses 9.0, 9.1 are provided in analogy to the preceding embodiments in the individual segments 2.1, over which the rigidity of a segment 2.1 compared to a trained as a full-form segment especially at the portion of the contact portion 21 .0 is significantly reduced, at which the segment 2.1 can be brought into engagement with the friction surface 10 of the first friction element 1.

Thus, inter alia, in each case a central recess 9.0 is provided, which adjoins in the extension direction of a segment arm 8.1 and is formed in the segment 2.1. This central recess 9.0 is made in the form of a wedge-shaped depression in the segment 2.1. Further, by making the segment 2.1 of a more yielding material than the support structure 8, the recess 9.0 allows it Contact area 21 .0 to deform elastically in the direction of the support structure 8 when a segment 2.1 (due to a rise in temperature) to a greater extent (as in normal operation) is pressed against the friction surface 10 of the first friction element 1. The additional lateral recesses 9.1 in the form of openings or cavities provided adjacent to this central recess 9.0 additionally reduce the rigidity of the segment 2.1 and thus support the ability of a segment 2.1 to increase in the direction of the axis A or (radially) in temperature Direction of the support structure 8 can be elastically deformed at least to some extent normal force to compensate for a greater extent of a segment 2.1. The (four) lateral recesses 9.1 are in the form of a chamber and in pairs in a segment 2.1 adjacent to the associated segment arm 8.1 such that the end section 8.3 of a segment arm 8.1 each between two pairs of successively arranged in the radial direction lateral recesses 9.1 in the segment 2.1 extends into it.

FIGS. 8A and 8B show a slightly modified variant of the embodiment of FIGS. 7A to 7C, in which a support structure 8 ^{* is} likewise formed by a metallic insert.

Different from the support structure 8 of FIGS. 7A to 7C, only the design of the segment arms 8.1 ^* protruding radially from the support section 8.2 and their end sections 8.3 ^{* are} merely shown. While in the embodiment of FIGS. 7A to 7C the end sections 8. 3 of the individual segment arms 8. 1 are embedded in the individual segments 2. 1 but are not completely enclosed by them, the embedded end sections 8. 3 ^{* of} the segment arms 8. 1 ^{* are} in the exemplary embodiment of FIGS. 8A and 8B completely within a 2.1 segment and completely enclosed by this. In a modification of the embodiment of Figures 7A to 7C, Figures 8A and 8B further show an alternative embodiment of the segments 2.1, in each of which a segment 2.1 by two circumferentially opposite lateral (larger) recesses 9.1 is elastic. The two recesses 9.1 of a segment 2.1 lie on different sides of the associated segment arm 8.1 transverse to the extension direction of the segment arm 8.1 side by side, so that the end section 8.3 ^{* of} the segment arm 8.1 ^* extends between them. In the exemplary embodiments of FIGS. 7A to 7C and 8A to 8B, the portion of the contact region 21 .0 to be brought into contact with the friction surface 10 of the first friction element 1 always lies with a width between the end of the associated segment arm 8.1 or 8.1 ^* is many times smaller than the length of the segment arm 8.1 or 8.1 ^* . In this way, starting from the support section 8.2 in the direction of the section of the segment 2.1, which is frictionally engageable with the friction surface 10 of the first friction element 1, first a section in the form of the segmental arm 8.1 or 8.1 ^* , which includes a material with comparatively low coefficients of thermal expansion is produced before it is followed by a section of a material having a comparatively large coefficient of thermal expansion, wherein the thickness of this section lying between segment 8.1 and 8.1 ^* and the friction surface 10 of the first friction element 1 by a multiple smaller than the length of the segment arm 8.1 or 8.1 ^* . Thus, the risk of jamming due to excessive thermal expansion of the segment 2.1 of the material having the larger coefficient of thermal expansion can be further reduced.

On the basis of the illustrated embodiments of Figures 4, 5, 6A to 6C, 7A to 7C and 8A to 8B is in each case an elastic support of at least a portion of the friction surface 20 having contact portions 21 1, 21 1 '21 .0 a second friction element 2, 2nd In addition, a plate-spring-like design can be realized via the embodiments shown, which shows a degressive behavior, so that the elastic yielding of the respective contact region 21 1, 21 1 ', 21 .0 is particularly large in order to significantly reduce a normal force increase and thus an increase of a holding torque for the locking of a motor vehicle part, so that a lock on the locking device can be easily solved even at an elevated operating temperature again. LIST OF REFERENCE NUMBERS

1 (first) friction element

10, 10 ^* (first) friction surface

2, 2 ', 2 ", 2 ^* (second) friction element

2.1 Segment

20, 20 ^* (second) friction surface

21 .0 contact area

21 1, 21 1 ', 21 1 ^* contact area

21 1 a, 21 1 a 'Installation section

21 1 b edge section

212, 212 ', 212 ^* intermediate area

22 supporting structure

220 support section

23 ^* (rigid) connecting section

23, 23 '(elastic) connecting portion

23.1, 23.1 'Basic Rib

23.2a, 23.2b force introduction rib

23.2a ', 23.2b' force introduction rib

231, 232 Jetty

24 (rigid) connecting section

25 positive locking area

26 fixing bar

3 wave

31 (lower) end section

32 (upper) end section

35 positive locking area

4 Elastic element

5 housing

51 housing base

52 housing upper part

53 (lower) bearing

54 (upper) bearing

6 recess

60, 61 inner surface

7 recess

8 support structure

8.1, 8.1 ^* Segment arm 8.2 support section

8.3, 8.3 * End section

8.5 positive-locking area

9.0 (central) recess

9.1 (lateral) recess

A housing axis

D Roof area d Thickness

EB catchment area

F _N force

g segment distance

H tailgate

K vehicle structure

L cargo space

le length

length

0 door opening

Rear side

Ri effective direction

S side door

s suspension travel

Z intermediate medium

Claims

claims

Locking device for locking a movable with respect to a motor vehicle structure motor vehicle part, which is locked by means of the locking device in a displacement area in a respective achieved by displacement rest position, with

- With at least a first friction element of the locking device having a first friction surface, and

- At least a second friction element of the locking device, which has a second friction surface and the second friction surface for locking the motor vehicle part can be brought into contact with the first friction surface of the first friction element, that the second friction surface bears under static friction conditions on the first friction surface, wherein the second friction element a support structure, via which the second friction element is mounted in the locking device, as well as at least one connected to the support structure contact region having at least a portion of the second friction surface, characterized in that the contact region (21 1, 21 1 ', 21 .0 ) is elastically supported at least in sections on the support structure (22, 8, 8 ^* ).

Locking device according to claim 1, characterized in that the contact region (21 1, 21 1 ', 21 .0) at least in sections in the direction of the support structure (22, 8, 8 ^* ) is movable, when the second friction element (2, 2 ', 2 ") abuts on its friction surface (20) on the friction surface (10) of the first friction element (1).

Locking device according to claim 1 or 2, characterized in that the contact region (21 1, 21 1 ', 21 .0) on the second friction element (2, 2', 2 ") is less rigid than that formed with the contact region (21 1 , 21 1 ', 21 .0) connected support structure (22, 8, 8 ^* ).

4. Locking device according to one of claims 1 to 3, characterized in that the contact region (21 1, 21 1 ', 210) on the support structure (22, 8, 8 ^* ) integrally formed or positively connected to the support structure (8, 8 ^* ) connected or integrally formed with the support structure (22).

5. Locking device according to one of the preceding claims, characterized in that at least one recess (6, 6 ', 7, 9.0, 9.1) in a portion of the friction element (2, 2', 2 ") is provided, the contact area (21 1, 21 1 ', 21 .0) with the support structure (22, 8, 8 ^* ) connects.

6. Locking device according to one of the preceding claims, characterized in that the second friction element (2, 2 ', 2 ") has a connecting portion (23, 23') over which at least a portion (21 1 a, 21 1 a ') the contact region (21 1, 21 1 ') is elastically connected to the support structure (22).

7. Locking device according to claim 6, characterized in that the connecting portion (23, 23 ') is formed such that it connects at least one portion (21 1 a, 21 1 a') of the contact region elastically with the support structure (22).

8. Locking device according to claim 5 and one of claims 6 or 7, characterized in that the at least one recess (6, 7) in the connecting portion (23, 23 ') is formed such that an elasticity of the connecting portion (23, 23' ) and / or the contact region (21 1, 21 1 ') is provided or increased.

9. Locking device according to claim 8, characterized in that with the at least one recess (6, 6 ', 7) with the contact region (21 1, 21 1') associated rib structure of the connecting portion (23, 23 ') is defined.

10. Locking device according to one of the preceding claims, characterized in that the second friction element (2, 2 ', 2 ") is made of at least two materials having different thermal expansion coefficients.

1 1. Locking device according to claim 10, characterized in that the contact region (21 1, 21 1 ', 21 .0) is made of a material having a greater thermal expansion coefficient than the material from which the support structure (22, 8, 8 ^* ) is made.

12. Locking device according to one of the preceding claims, characterized in that the second friction element (2 ") a plurality of individual spaced-apart segments (2.1) each forming a contact region (21 .0) with a part of the friction surface (20).

13. Locking device according to claim 12, characterized in that in each case one segment (2.1) is provided on a segment arm (8.1, 8.1 ^* ) of the support structure (8, 8 ^* ), which is supported by a support section (8.2) of the support structure (8, 8 ^* ) protrudes toward the first friction surface (10).

14. Locking device according to claim 13, characterized in that the segments (2.1) are each positively and / or non-positively connected to a Segmentarm (8.1, 8.1 ^* ) or molded onto this. 15. Locking device according to claim 5 and one of claims 12 to 14, characterized in that a segment (2.1) has at least one recess (9.0, 9.1) over which an elasticity of the segment (2.1) is provided or increased.