WO2007025687A1

WO2007025687A1 - Fixing device

Info

Publication number: WO2007025687A1
Application number: PCT/EP2006/008391
Authority: WO
Inventors: Wilhelm Schneider
Original assignee: Richard Bergner Verbindungstechnik Gmbh & Co Kg
Priority date: 2005-08-30
Filing date: 2006-08-26
Publication date: 2007-03-08
Also published as: DE112006001792A5

Abstract

The invention relates to a fixing device (1) for fixing a top (28) to a base part (27). One fixing end of the fixing device (1) comprises an anchor element (3, 39, 58, 61) for pre-assembly with the base part (27) and a snap-fastening element (2) for fixing the top (28) to the fixing end that faces away from the free end. The snap-fastening element (2) comprises at least one sprung arm (6) that acts as an energy store and that carries a snap-in element (9) and at least one spring-loaded steadying element (14). The snap-in element (9) and the steadying element (14) form a clearance (17) for holding a partial region of the top (28) between the two elements. The fixing device (1) enables the top (28) to be simply fixed to the base part (27) in a vibration-free manner by means of the snap-in connection.

Description

description

fastening device

The invention relates to a fastening device for fixing an attachment on a base part. Such fastening devices are used for example in the automotive industry. In the automotive industry, it is customary today either to encapsulate the vehicle engine with respect to the outside world or at least to cover it with a design hood. The complete encapsulation or encapsulation of the engine is used in particular in diesel engines or high-noise gasoline engines. The use of a cover is usually for visual reasons and to prevent improper access to the engine from the outside. With reference to a vehicle, the vehicle engine thus forms the base part and the encapsulation or the design hood forms the attachment.

In a simple variant, such a fastening device is designed as a snap connection. For this purpose, the fastening device has an anchoring to a free end for pre-assembly on the base part and a snap element for Schnappfixierung the essay on the free end facing away from fixing. A snap connection allows a particularly simple assembly of two components. A releasable and positive snap connection usually has a snap element for form-fit generation, cooperating with the snap element mating surface, a guide or a bearing of the snap element, and a force storage, as an elastic element for generating the Einschnappbewegung of the snap element and for fixing the position of the snap element in latched state is suitable. In addition, a release element is provided for levering the snap element and for releasing the snap connection. This definition of a snap connection is Carl-Otto Bauer, Handbook of connection technology, Carl Hanser Verlag, Munich, 1991, p 294 ff., ISBN 3-446-14609-1, taken.

Since the attachment is easily snap-fixed to the base part by means of the fastening device, the mounting of the attachment on the base part is simplified considerably. The attachment can be already before mounting on the base part with one or more Fastening devices provided. It is then connected on site in a simple manner via the snap fixing with the essay. Since the anchorage to the base part and the snap element are fixedly mounted on the attachment, there are no loose and therefore difficult-to-handle small parts, such as screws, nuts or the like. Thus, manufacturing processes can be considerably simplified, which is particularly important for a high cost pressure exposed industries, such as the automotive industry, is important. In this case, in the final assembly or even in case of repair, simply attach the attachment with its one or more snap elements to the anchorage or to the anchors of the base part. It is thus possible to purchase a completely prefabricated and ready-to-mount attachment either from a supplier or else to manufacture it in an optionally also locally remote part. It is also conceivable, of course, that the snap elements are fixed to the base part and during assembly of the essay, which is designed with correspondingly shaped openings, is slipped over it.

In DE 198 36 108 A1 designed as a plug-in snap connection is described. This plug-in coupling has a socket-like coupling part with a conical intermediate wall designed as an insertion section, which tapers in the longitudinal direction with respect to an insertion opening and which ends in a ball socket. To the intermediate wall, a tubular outer wall is formed for insertion into a socket arranged on a socket. The pan-like, made of a thermoplastic elastomer or rubber coupling part is elastic. On a base part a bolt-like coupling part is attached. This bolt-like coupling part carries at its end a ball. For snap fixation, this ball snaps into the pan pan. Since the socket-like coupling part is made of an elastic material, thus the two components are connected to each other vibration-decoupled. In this way, for example, a design cover can be mounted on a cylinder head cover of an engine or a bumper cover on a bumper of a motor vehicle. The vibration-decoupled connection ensures that no driving noises can occur as a result of rattling or the like.

A development of this concept is described in DE 202 16 836 U1. Here, the intermediate wall serving as an insertion section, to which the ball socket is attached, is closes, wavy. Thus, not only compensating movements in the axial direction, but also in the radial direction relative to the central longitudinal axis of the bolt-like coupling part are possible after mounting the attachment to the base part. The vibration decoupling should be further improved.

In DE 203 15 778 U1 a mechanically more stable variant of this concept is described. For this purpose, a metallic spring clip for receiving the ball head of the bolt-like coupling part is arranged in a made of plastic substantially annular support member instead of an intermediate wall made of plastic. The spring clip and the ball head are designed so that when a snap-in of the ball head in the spring clip, a latching connection between the spring clip and the ball head is formed. This variant should not only be mechanically more stable, but also compensate for influences due to fluctuating or higher temperatures, such as those present in the engine compartment of a motor vehicle.

In DE 20 2004007 055 U1, a mounting flange is finally described following the same basic concept. This mounting flange in turn receives a fixed at the end of a bolt-like coupling part ball. The bolt-like coupling part is in turn connected to the base part. The mounting flange consists of a sleeve which receives the ball, and an annular flange. To fix the mounting flange in the essay of the mounting flange carries in the region between its annular flange and sleeve deformable wings. The mounting flange is pushed with pressure into the attachment, so that the wings deform elastically. By elastic deformation of the wings, the mounting flange is held in the cover. The mounting flange as well as the cup-like coupling part in the other embodiments of this known from the prior art construction of a thermoplastic elastomer or rubber. A disadvantage of this known from the prior art concept is first the need for the use of elastomer parts. Elastomer parts are very expensive. They can only be produced with great effort. On the other hand, it is necessary for the realization of this concept known from the prior art to provide undercuts on the elastomer part. The production of these undercuts is difficult because when injecting the elastomer parts slide or variable mandrels must be used. manufacturing - A -

technically disadvantageous in the known from the prior art concept is still the need to make pre-assembly on both the base part and the essay. This is particularly disadvantageous if - as usual - the engine and the attachment are made by different manufacturers. The fastening device can only function if the manufacturers coordinate with regard to the manufacture and pre-assembly of the fastening device.

Based on these disadvantages, the invention has for its object to simplify a fastening device of the type mentioned so that it is manufacturing technically cheaper and thus more cost-effective to produce. This object is achieved by the combination of features of claim 1 in an inventive manner. The dependent claims relate in part to advantageous and in part self-inventive developments of the invention.

The invention is based on the idea of combining parts of the fastening device in an assembly in such a way that it can be preassembled on the base part or on the attachment so that it can then be easily inserted into a corresponding recess on the respective other part. Preferably, the base part also serves as a carrier for the fastening device. In special cases, however, the attachment can also carry the fastening device. An advantage of the invention is the pre-assembly and their ease of assembly and disassembly. Furthermore advantageous is the elimination of elastomer parts or rubber parts, which makes the production more cost effective. In addition, the invention also simplifies the disposal or recycling of the fastening device or the parts provided with the fastening device. The invention eliminates the need to dispose of non-metallic parts of the fastening device separately from their support parts, that is, as a rule, the base part. Since all parts of the fastening device as well as the base part can be made of metal, the fastening device can be easily disposed of with the base part, for example, the vehicle engine, which also consists predominantly of metal, in one operation or the various metals are separated and then disposed of. The erfindungmäßige fastening device has an anchorage at its free end for pre-assembly on the base part and a snap element for Schnappfixierung the article on the free end facing away from fixing. Furthermore, at least one effective as a force storage and a snapper carrying spring arm and at least one resilient counter-holder are arranged on the snap element. Snapper and anvil form a space for receiving a portion of the essay between them. Thus, this essay is always clamp fixable when it has a contour that can be resiliently held by the snap element. Such a contour is, for example, a bore introduced into the attachment, which is penetrated by the spring arm from the side of the attachment facing the base part to its side facing away from the base part, so that the spring arm on the opposite side and the counter support on the base part facing side for clamping fix.

Since the clamping fixation of the attachment takes place elastically, also attachments with different thicknesses can be securely clamped. The differences in thickness are compensated by elasticity of the spring arm and resilient counterholder. The spring arm and counterholder clamp the attachment between them in the manner of clamping jaws. Due to the spring elasticity of the spring arm and counter-holder of the firmly clamped essay against the base part is so resiliently mounted.

Furthermore, in particular large-scale essays, which are mounted by means of a plurality of fastening devices on a base part, easy and convenient to install. An oblique attachment of the attachment relative to the base part still allows a secure mounting of the attachment to the base part, since misalignment can be compensated by means of the spring elasticity.

Due to the elastic snap fixing of the attachment to the base part of the article is also mounted vibration-decoupled from the base part. Vibrations of the base part are thus not transferred to the attachment, so that striking of the attachment on the base part is reliably avoided. Such a vibration-mechanical decoupling of the base part and attachment is particularly important in the automotive industry. For example, a side panel or a bumper cover can be fixed as an attachment to the body in a simple manner, without that incurred during the driving of a motor vehicle vibrations are passed to this panel. Even a decorative cover or design hood of an engine, as it is nowadays, in particular for exclusive cars as a cover over the engine block arranged for aesthetic reasons, thus can be decoupled vibration technology from the engine block and does not cause any disturbing noise.

In a preferred variant, the snap element is designed as a spring-elastic Blechbie- part. Such a bent sheet metal part is simple and inexpensive to produce. In addition, the properties of the snap element in a wide range can be influenced in a simple manner on the choice of sheet material, sheet thickness and bending geometry.

In a further development, the snap element has a planar base plate, from whose base plate edge one or more spring arms project substantially vertically. These spring arms each have a snapper on their free ends facing away from the base plate. Furthermore, the snap element has one or more out of the base plate edge in the direction of the snapper protruding counter-holder, each having a plane substantially equal to the base plate extending counter-surface. Thus, in particular, a plate-shaped attachment is securely supported on its counterpart surfaces facing side by the counter-holder and supported from the inside.

Suitably, the snapper is bent out of the free end of the spring arm such that the spring arm form a long leg and the snapper a short leg of an acute angle. By means of the length of the spring arm and the snap can thus adjust the size of the free space between the one or more snappers and the one or more butts for receiving the essay exactly or fine-tune. The length and the thickness of the spring arm and the snapper are also decisive for the forces during assembly and disassembly of the essay. In a preferred development, the snapper has a guide surface in its region adjoining the spring arm at an acute angle, and a bend at its end facing away from the spring arm. Thus, the snap element can be interpreted such that it engages with the free ends of his one or more spring arms through a recess introduced into the attachment, in particular a hole and thus can be threaded into this recess as it were. Since the guide surfaces of the snapper are bent away from its base plate to the outside, they come successively with the walls of the recess in contact, press each of the spring arms radially towards the central longitudinal axis of the snap element and center the snapper automatically in the recess.

In a variant, the bend at the end of the guide surface of the snapper extends substantially perpendicular to the spring arm. The bend thus forms an undercut for locking the snap element on the attachment, in which the bend completely over-snaps the edge of the recess in the attachment. Thus, the essay is held flat between the anvil surfaces of the anvil and the turns of the snapper. Due to the resulting in particular in a plate-like essay comparatively large bearing surface of the essay is thus particularly securely clamped by means of the snap element on the base part.

In another variant, the deflection of the latch extends at an angle between 70 ° and 110 °, preferably substantially perpendicular to the guide ^"ä surface. The deflection thus forms a Entriegelungsschräge for the snap element. The snapper abuts with its bend on the facing it, the edge of the When the snap element is released in the opposite direction to the latching direction, the attachment can thus be unlocked by simply pulling it away from the snap element Direction given a play-free arrangement of the essay.

In an advantageous variant, the width of the spring arms at their free end is greater than the maximum distance between two adjacent spring arms. This reduces the risk of entanglement of fasteners transported together as bulk material in a container. significantly reduced. Engagement between two spring arms of a fastening element by a spring arm of a second fastening element adjacent in the container is thus precluded. This saves time in removing the fasteners from the container after transport for assembly.

A further embodiment relates to a snap element having a substantially planar base plate, with at least one edge arm pivotally mounted on the base plate by means of a leaf spring joint and with a clamping wedge acting as a pivot drive for the spring arm, can be inserted into the snap element. In this variant, the spring arms can be designed so that they can be pushed through the recess without resistance. After pushing the spring arms of the snap element through the recess of the clamping wedge is inserted into the snap element. As a result, the spring arms pivot in relation to the central longitudinal axis of the snap element in the radial direction to the outside, so that the bends of the snap engage over the edge of the recess for snap fixation. Since the spring elements swivel back into their unloaded starting position after removal of the clamping wedge, this type of clamping fixation of the clamping wedge can be solved in a simple manner and remove the attachment again from the base part.

In a further development, the clamping wedge carries a cover plate on its free end remote from the snap element in the final assembled state. This cover plate can be designed in particular so that it is flush with a plate-like attachment. For this purpose, the plate-like attachment is provided in the area with the recess to be swept by the snap element with a molding, so that after the insertion of the wedge not only the clamping fixation of the snap element takes place in the plate, but also the snap element is completely covered. In particular, in places where a flat surface is desired, such as in design hoods for engines, thus the snap element is hidden from view, so that the overall aesthetic impression is improved.

In a preferred variant, the snap element is made in one piece. This one-piece design can be achieved in the manufacture of the snap element as a sheet metal bent part of a flat sheet by means of a sequence of defined bends. The production As a component leads to the fact that only the snap element as a whole and the base part must be connected to each other. Elaborate manufacturing operations for assembling the snap element can therefore be omitted.

In a special embodiment of the invention, the counter-holder is designed as a separate component, preferably as a seal. The counter-holder must fulfill two tasks according to the concept of the invention, namely after insertion of the snap element in the essay, position the snap element of the base in the tower and bring in the final assembly state directed against the spring arms counter-holding forces, so that the essay in its defined end position is secured or resiliently mounted relative to the base part. In other words, when inserting the snap element with the spring arms, the snap element is moved a little too far in the direction of the attachment, so that the spring arms can rebound. As a result of the resilient opposing force of the counterholder which then builds up, the snap element is, as it were, pulled back into a final assembly position. This retraction is similar to tightening a screw in a threaded connection. In the special embodiment of the counter-holder is designed as a separate intermediate between the essay and the base member. Particularly advantageous is the use of a spring-elastic, spring forces and thus high opposing forces applying seal. This seal can be preassembled, for example, by an adhesive bond with the base part. In addition to the secondary function as counterholder, the seal also fulfills the primary function of the seal, so that in this design an individual part can be saved compared to a variant with a separate counterholder and separate seal.

Preferably, the anchoring of the snap element on the base part is designed as a bolt. This bolt is fastened in a known manner to the base part and thus fixes the snap element on the base part reliably.

In a variant, an outer contour, in particular a knurling is introduced on the bolt. In this way, the bolt can be easily installed by pressing into a hole introduced into the base part. In another variant, the bolt carries an external thread. This external thread can be made self-tapping in a comparatively soft material of the base part. However, it is preferably designed as a screw thread, which can be screwed with a introduced in the base part corresponding internal thread. Thus, the bolt can be fixed by means of a high holding force on the base part. In addition, the fastening device can be easily disassembled and replaced, for example.

In a further variant, the bolt is part of an assembled from a bolt-shaped fixing part and a sleeve-shaped holding part assembly unit. Such an assembly unit is described in particular in WO 95/21335. In this case, the sleeve-shaped holding part is firmly connected to the base part, for example, pressed. The bolt and the bolt connected to the snap element are held and guided in the sleeve-shaped holding part. By means of the bolt or the base can be attached to another part, in particular screw. Finally, by means of the snap element on the base part an essay snap fix. Individual variants of a bolt-shaped fixing part and a sleeve-shaped holding part can be found in WO 95/21335. The entire disclosure of WO 95/21335, which is based on the present applicant, is expressly incorporated herein by reference. All the features described and claimed there are also claimed for the present application in combination with the inventive fastening device.

By means of the use of such a mounting unit, complex production and assembly tasks can also be fulfilled. For example, the base part is the cylinder head cover of a motor vehicle engine. The cylinder head cover is usually bolted to the cylinder head. The snap elements on the bolts can be used after screwing to snap over the cylinder head cover, a motor cover snap fixing, which is attached there for aesthetic reasons. Since the cylinder head cover can be screwed to the cylinder head by machine and the engine cover can be fastened to the cylinder head cover with just a few simple steps, a decisive step has been taken towards rational production.

In an expedient variant, the base plate of the snap element has a receiving bore for the positive connection of the anchoring with the snap-in element. element on. Thus, a simple connection between the snap element and the anchorage is achieved.

In a further development, a bolt serving as anchoring is pushed through the receiving bore for positive connection with the snap element. This form-locking connection of the bolt with the snap element takes place, for example, in that a bolt provided with a bolt head and an undercut which adjoins the bolt head in the longitudinal direction is driven through a receiving bore in the snap element, the diameter of which essentially corresponds to the diameter of the bolt. By driving the bolt down to the stop of the bolt head on the base plate, the edges of the receiving bore are deformed in such a way that the bolt can be displaced through the receiving bore and the edges in the pushed-through state at least partially behind the undercut directly adjoining the bolt head. attacks. In this way is a captive connection between bolts and

Ensures snap element that simultaneously fixes the snap element of their position directly on the bolt head. Such a fastening device can therefore be mounted very easily. For a defined bending of the receiving bore when Hindust rubbing the bolt, the receiving bore may be provided for example with nose-like recesses in the region of its edge.

In another variant, the anchoring and the snap element are integrally designed as a resilient bending part. In this case, a base plate carries at least one spring arm and at least one counter-holder, which protrude from the base plate in one direction. In addition, at least one retaining arm for anchoring the fastening device on the base part protrudes from the base plate in the opposite direction. This holding arm can be snap-fixed in a recess on the base part, for example. It is therefore a clip-like attachment and anchoring of the fastener on the base part. Various embodiments for such a clip are shown, for example, in the handbook of connection technology by Carl-Otto Bauer cited on page 306. Such a clip-like connection is particularly suitable when the attachment to be fastened is light and therefore the holding forces to be applied via the anchoring to the base part are low. In a preferred development, the holding arm has a locking element for fixing the anchoring to the base part. Thus, the anchoring can be fixed in a simple manner, in particular in a plate-like base part in a recess. For this purpose, the fastening element is inserted with its holding arms in a recess provided in the base part. The locking elements, which preferably point radially outwardly relative to the central longitudinal axis of the fastening, are designed, for example, as tabs which protrude obliquely upward in the longitudinal direction. These tabs are compressed when pushing the anchorage through the recess. As soon as the region of the holding arm with its fixing lug arranged thereon is pushed completely through the recess, the fixing lug moves radially outward in the direction of the body longitudinal axis due to its spring elasticity and clamps the holding arm to the plate-like holding part.

Suitably, the axial distance in the direction of the central longitudinal axis from the approach of the counter-holder to the top of the locking elements is smaller than the thickness of the base part. Thus, a secure positive fixing of the clip in the recess of the base part is ensured by an undercut arrangement of the locking elements on the hole edge of the recess and jamming of the locking elements on the underside of the base part.

Finally, claims 20 to 24 relate to a connection arrangement realized with a fastening device of the above type. The connection arrangement has a pre-assembly position and a final assembly position. In the pre-assembly, the anchoring is fixed to the base part. In the final assembly position, the attachment to be fixed on the base part is then fixed by means of the fastening device. In a basic version, the latches fixing the attachment each pass through a through hole in the attachment. In a particular embodiment, this through hole may have an additional cup-like indentation. This cup-like shape serves as an additional receiving space the clamping wedge, which is required for a previously described embodiment of the fastening device. Advantageously, a spacer sleeve can be provided in the region of the anchoring, in particular in the region of an anchoring designed as a bolt, in order to ensure a spatial distance between the base part and the attachment in the final assembled state. This distance is used for the spatial decoupling of base part and attachment. This may be necessary, for example, due to noise or thermal reasons. Manufacturing technology is simple and easy to automate screwing the anchorage in the pre-assembly.

Production technology favorable, because also easy to install, is a snapping the anchorage to the base part. For this purpose, not only the snap element, but also the anchorage must be designed as a resilient sheet metal bent part. This variant is assembly technology and manufacturing technology favorable and thus contributes to the cost reduction.

The invention will be explained in more detail with reference to a drawing. The individual figures show:

1 shows a fastening device with a snap element and an anchor in the form of a screw in a side view, Fig. 2, the snap element in a perspective view, Fig. 3, the snap element in a plan view from above, Fig. 4, the snap element in a side sectional view according to the section DD of FIG. 3,

1 in the mounted state and an attachment to be mounted, FIG. 7 the attachment when attaching to the snap element for assembly, FIG. 8 the attachment during the Pressing on the snap element, FIG. 9 shows the attachment pressed onto the snap element in the overpressed state, FIG. 10 shows an alternative attachment in the final assembly state, FIG.

11 shows a second embodiment of the fastening device with a modified snap element in the final assembly state, 12 shows a third embodiment of the fastening device with a knurled bolt as anchoring prior to assembly,

13 shows a fourth embodiment of the fastening device with a further knurled bolt as anchoring in the assembled state, FIG. 14 shows a fifth fastening device from FIG. 13 with an alternative attachment and a wedge to be mounted,

FIG. 15 shows the fastening device from FIG. 14 during the application of a wedge for fixing the spring arms, FIG.

FIG. 16 shows the fastening device from FIG. 15 with the wedge completely inserted; FIG. 17 shows a sixth embodiment of the fastening device with a seal;

18 shows a seventh embodiment of the fastening device with a sleeve as a spacer,

19 shows an eighth embodiment of the fastening device according to WO 95/21335 before assembly, FIG. 20 shows the fastening device from FIG. 19 in the final assembled state with mounted attachment, FIG.

21 shows a ninth one-part embodiment of the fastening device in a perspective side view,

21 shows the fastening device from FIG. 21 in a plan view, FIG. 23 shows the fastening device from FIGS. 21 and 22 before inserting the anchoring into the base part,

FIG. 24 shows the fastening device from FIG. 23 during insertion into the base part, FIG.

FIG. 25 shows the fastening device from FIG. 24 with the anchoring pushed into the base part in the overpressed state and FIG

Fig. 26, the fastening device of Fig. 25 in the final assembled state.

Fig. 1 shows a fastening device 1, comprising a snap element 2 and designed as a screw anchor 3, in a side view.

Fig. 2 shows the snap element 2 in a perspective view. The snap element 2 has a flat base plate 4, from whose base plate edge 5 spring arms 6 protrude substantially perpendicular. The spring arms 6 thus run in the sentlichen in the direction of extending through the center of the base plate central longitudinal axis 7 of the snap element 2. Each spring arm 6 is bent at its base plate 4 facing away from the free end 8 and goes into a snapper 9 over. In this case, the snapper 9 is bent relative to the central longitudinal axis 7 of the snap element 2 in the radial direction 10 substantially on the base plate 4 out. The spring arm 6 forms a long leg and the snapper 9 a short leg of an acute angle 11, see in particular Fig. 4th

Each snapper 9, in its region adjoining the spring arm 6 at an acute angle, has a guide surface 12 on its outer side facing away from the base plate 4. The guide surface 12 extends from the free end 8 obliquely outwards. Their distance in the direction perpendicular to the central longitudinal axis 7 radial direction 10 increases seen from the free end 8 in the direction of the base plate 4 consequently.

At its end opposite the free end 8, the snapper 9 has a bend 13. The bend 13 extends substantially at right angles to the spring arm 6 in the radial direction 10 and extends in a direction equal to the plane of the base plate 4. The bend 13 is bent by the snapper 9 bearing the guide surface 12 on its outside in the direction of the spring arm 6.

From the base plate edge 5 are also in the direction of the snapper 9 more counter-holder 14 at an obtuse angle 15 from. The end of each counter-holder 14 is bent to a counter-holder surface 16 and points in the radial direction 10 in the direction of the central longitudinal axis 7. Thus, the counter-holder surface 16 extends equal to the plane of the base plate 4 and thus also to the bends 13 of the spring arms 6. Between the bends 13 of the spring arms 9 and the anvil surfaces 16 of the anvil 14 thus a defined space 17 is set.

In particular, FIG. 3 shows that the base plate 4 is pierced centrally by a bore 18, on the circumference of which a plurality of nose-like recesses 19 extending into the material of the base plate 4 are arranged. Fig. 5 shows the executed as anchoring screw in a side view. The screw 3 is in this case designed as a Linsenkopfschraube, so that the screw head 20 widened from its head end 21 ago in the screw longitudinal direction 22 on the screw shaft 23 out. The head end 21 facing away from the end of the screw head 20 is formed as a screw flange 24. The screw shaft 23 carries almost over its entire length an external thread 25. Directly to the screw flange 24 closes in the longitudinal direction of the screw 22, an undercut 26 without thread. In this case, the undercut 26 has a smaller diameter than the external thread 25.

The snap element 2 and the screw 3 are assembled to the fastening device 1, which is apparent from Fig. 1. For this purpose, the screw 3 is driven with its screw shaft 23 through the bore 18 of the base plate 4 of the snap element 2. The diameter of the bore 18 corresponds substantially to the diameter of the screw shaft 23. By driving the screw shaft 23 until it stops against the screw flange 24 on the base plate 4, the edges of the bore 18 are deformed such that the screw shaft 23 passes through the bore 18 is displaceable and the edges of the bore 18 at least partially engage in the undercut 26 for fixing the snap element 2 on the screw 3. In this way, the snap element 2 is captively secured to the screw 3. By means of the nose-like recesses 19 in the region of the edge of the bore 18, the bore edge is segmented into four equally sized lobes 48. These tabs 48 allow for easier bending of the base plate 4 at its edge.

Fig. 6 shows the fastening device 1 with the snap element 2 and the screw 3 in the pre-assembly. The screw 3 is firmly screwed to a base part 27. For this purpose, an internal thread 70 has previously been cut into the base part 27.

When firmly screwed in, the underside of the screw flange 24 oriented in the direction of the screw shank 23 presses the base plate 4 of the snap element 2 against the surface 34 of the base part 27, so that the snap element 2 is secured to the base part 27 without play. FIG. 6 also shows an attachment 28 which is intended to be snap-fixed by means of a through-bore 29 on the snap element 2. The article is placed on top of the guide surfaces 12 of the snapper 9 of the snap element 2 from above in the direction of the central longitudinal axis extending attachment direction 30 with its through hole 29.

In Fig. 7 the attachment of the attachment 28 is shown with its through hole 29 on the snap element 2 for mounting. The through-hole 29 touches the guide surfaces 12 of the snapper 9 with its lower hole edge 31.

If a force is exerted on the attachment 28 further in the direction of attachment 30, then the lower hole edge 31 of the attachment 28 slides along the guide surfaces 12 of the snapper 9, see FIG. 8. In this way, the spring arms 6 are in the radial direction 10 to the central longitudinal axis 7 of the attachment device 1 pivoted out. In this way, a threading through the spring arms 6 through the through hole 29 through it in a simple manner possible. The lens shape of the screw head 20 allows the Einschwenkbarkeit the spring arms 6. At the same time the screw head 20 is effective as a stop for the spring arms 6.

If, furthermore, a force is exerted in the attachment direction 30 on the attachment 28, the snapper 9 successively passes through the through bore 29 along the central longitudinal axis 7. As soon as the latches 9 are fully pushed with their bends 13 through the throughbore 29, the spring arms 6 pivot radial direction 10 from the central longitudinal axis 7 ago in the radial direction 10 to the outside, so that the bends 13 protrude above the upper edge of the hole 32. The attachment 28 is, as shown in FIG. 9, with its underside 33 on the counter-holder surfaces 16 of the counter-holder 14 and pushes this counter-holder 14 in the direction of the surface 34 of the base member 27. In this way, the free pivotal movement of the spring arms 9 in the radial direction 10 to the outside is possible.

After releasing the article 28, the counter-holders 14 are relieved. The attachment 28 now rests with its underside 33 on the counterholder surfaces 16 and with its upper side 35 against the bends 13 of the snapper 9, as can be seen in FIG. 10. The attachment 28 is thus resiliently clamped between the counter-holder surfaces 16 and the bends 13. The clear width of the open space 17 in Direction of the central longitudinal axis 7 between the turns 13 of the snapper 9 and the anvil surfaces 16 of the anvil 14 is dimensioned slightly smaller than the thickness 36 of the cap 28, so that a secure and play-free snap fixing of the cap 28 is realized on the base part 27 and the top 28th from base part 27 is at the same time vibration decoupled.

The attachment 28 can also be designed so that the underside 33 used for the clamping fixation on the counterholds 14 is designed as a step. The thickness of the attachment 28 is significantly reduced in this embodiment in the region of the through hole 29 compared to the rest of the attachment. This is shown in FIG. 10 by the

Hatching indicated. The through hole 29 has here to the top 34 of the base member 27 toward a conical taper 38 as a contour. The larger diameter of this conical taper 38 is oriented towards the upper side 34 of the base part 27. The counter-holders 14 can thus be received by the conical taper 38. The conical taper 38 serves as an assembly aid when placing the attachment 28 on the snap elements 2 in the sense of centering. In this case, a clearance is left between the underside 33 of the attachment 28 and the upper side 34 of the base part in the non-tapered region of the attachment 28 for secure assembly. The counter-holders 14 can be compressed in the direction of attachment 30 during assembly. In the assembled state, however, a vibration decoupling between the base part 27 and top 28 is still guaranteed.

Fig. 11 shows a second embodiment of the fastening device 1 with a further snap element 2 in the final assembled state. The only modification is that the bend 13 on the snapper 9 now extends perpendicular to the guide surface 12 and extends as far as the spring arm 6.

The attachment of the attachment 28 on the base part 27 takes place analogously to the manner described in FIGS. 6 to 10. In the final assembly state, however, the snapper 9 are not flat with their bends 13 on the top 35 of the essay, but only on the upper edge of the hole 32 of the through hole 29 at. Since the bend 13 is also bent to the spring arm 6 out, the article 28 can thus by simply unscrew it from the snap element 2. A snagging of the snapper 9 with their bends 13 on the top 28 is thus avoided. According to the above-cited manual of the connection technology by Carl-Otto Bauer on page 294 for a snap connection, the combination of bend 13 and upper hole edge 32 is the release element of the snap connection.

FIG. 12 shows a third embodiment of the fastening device 1 with a knurled bolt 39, which serves as anchoring on the base part 27. The knurled bolt 39 also has a bolt head 41, to which an undercut 26 connects in the longitudinal direction 7 analogously to the bolt 3 described in FIGS. 1 to 11. By means of this undercut 26, the snap element 2 is held securely and captively on the knurled pin 39 before assembly.

Fig. 13 shows a fourth embodiment of the fastening device 1 with a further knurled bolt 39 as anchoring in the assembled state. Directly to the bolt head 41, in this embodiment, in contrast to the knurled bolt 39 shown in FIG. 12, a collar 42 adjoins. This collar 42 has a larger diameter than the knurling 40. At its fixing end, the knurled pin 39 has a centering pin 43. The knurled pin 39 is driven into the base part 27 with its centering pin 43 in front. Since the collar 42 acts when driving the knurled bolt 39 due to its larger diameter as a stop, only the knurled bolt portion is driven into the base part 27. The collar 42 thus serves as a spacer and sets a defined distance of the snap element 2 from the top 34 of the base member 27 fixed. The knurling 40 allows a secure hold of the knurled bolt 39 in the base part 27. On the snap element 2, a cap 28 is snap-fixed in the manner described in FIGS. 6 to 11.

14 shows a fifth embodiment of the fastening device 1 with a modified attachment 28. In the region of the through hole 29, the attachment 28 has a cup-like indentation 44. Thus, the cup bottom of the indentation 44 is lowered in the direction of the through hole 29 with respect to the upper side 35 of the attachment 28 in the direction of attachment 30. The spring arms 6 of the snap element 2 are in comparison to the previously shown snap elements 2 of the embodiments of FIG. 1 bi 13th more bent in the radial direction 10 on the central longitudinal axis 7 out. Thus, the bends 13 of the snapper 9 are at all only at the upper edge of the hole 32 of the through hole 29 at.

Due to the cup-like indentation 44, a receiving space 45 is formed such that the free ends 8 of the spring arms 6 are lower in the direction of the central longitudinal axis than the surface 35 of the attachment 28, so that the snap element 2 rests completely in the cup-like indentation.

Fig. 14 also shows a clamping wedge 46, which is designed substantially in the manner of a hollow cylinder. At its end facing the snap element 2, the clamping wedge 46 has a conical contour 49. At its the conical contour 49 in the direction of the central longitudinal axis 7 opposite end a cover plate 50 is arranged on the clamping wedge 46. 14 shows the fastening device in the previous day's position.

Fig. 15 shows the fastening device acc. The clamping wedge 46 engages with its konusförmigen contour 49 between the spring arms 6. The spring arms 6 are characterized with their bends 13 in the radial direction 10 relative to the central longitudinal axis 7 of the fastener 1 in the radial direction 10 pivoted outward. As a result, the bends 13 are now completely on the top 35 in the region of the through hole 29. The Schnappfixierung between the cap 28 and the base member 27 is secured by the clamping wedge 46 against snatching. At its end facing away from the snap element 2 in the direction of the central longitudinal axis 7, the cover plate 50 of the clamping wedge 46 terminates flush with the surface 35 of the attachment 28, in which it engages in a plate receptacle 51 arranged on the edge of the cup-shaped indentation 44. For a simple removal of the clamping wedge 46, a recess 52 is centrally provided in the cover plate 50 as an unlocking opening. By means of a tool, the clamping wedge 46 can be removed in a simple manner. F7ig. 17 shows a sixth embodiment of the fastening device 1 with a seal 53 in the final assembled state. At the snap element 2, no counter holder are fixed in this embodiment. The counterpart here is the seal 53 which is separate from the snap element and which is held on a seal receptacle 54 arranged on the underside 33 of the attachment 28. The conical taper 38 serves as a joining aid, see Fig. 10. The snap fixing of the cap 28 is such that the seal 53 is compressed upon pressing the cap 28, so that the spring arms 6 with the snappers 9 arranged thereon after passing through the through hole 29 press the attachment 28 from its upper side 35 against the seal 53.

Fig. 18 shows a seventh embodiment of the fastening device 1 with a spacer sleeve 55 as a spacer. The spacer sleeve 55 is captively connected, for example, in the manner known from WO95 / 21335 with the screw 3 and the snap element 2. It can therefore be handled as a unit in manufacturing. The embodiment of the fastening device 1 corresponds essentially to the first embodiment shown in FIGS. 1 to 10. Before screwing the screw 3 with the base part 27 is seen from the fixing end of the screw 3 on the screw 3, the spacer sleeve 55 is placed. This spacer sleeve 55 has a first flange 56 which bears against the underside of the base plate 4 of the snap element 2, and a second flange which rests against the upper side 34 of the base part 27. By screwing the screw 3 to the base part 27 thus the distance of the snap element 2 to the surface 34 of the base member 27 is precisely determined by the spacer sleeve 55, so that the distance between see the base member 27 and essay 28 in function of the sleeve length pretend leaves.

Fig. 19 shows an eighth embodiment of the fastening device 1 prior to assembly. This fastening device 1 has a retaining bolt 58, which is part of a composite of a bolt-shaped fixing part and a sleeve-shaped holding part 59 assembly unit. The sleeve-shaped holding part 59 is an undercut arrangement of a flange 57 a holding element 71 of a seal 72 captively connected to the base member 27. Such a mounting unit is described in WO 95/21335 with all the details.

FIG. 20 shows the fastening device 1 from FIG. 19 in the final assembled state. In this case, the fastening device 1 is fixed with its retaining bolt 58 to a further component 60, in particular screwed. On the snap element 2 of the attachment 28 is placed in the manner described. The further component 60 is, for example, a cylinder head which is screwed to a cylinder head cover forming the base part 27. In this case, the attachment 28 constitutes a design hood for covering the cylinder head cover and at the same time the entire engine housing. This design hood is vibration-decoupled to the cylinder head cover and thus to the engine housing.

Fig. 21 shows a ninth in this case one-piece embodiment of the fastening device 1 in a perspective side view. An embodied as a clip 61 anchoring is designed together with the snap element 2 as a one-piece elastic sheet metal bent part. The base plate 4 carries three spring arms 6 and three counter-holder 14, which project from the base plate edge 5 of the base plate 4 in the direction of the central longitudinal axis 7 upwards. Furthermore, from the base plate edge 5 in relation to the central longitudinal axis 7 opposite direction down three support arms 62 from. These three retaining arms 62 are bent towards one another with their insertion ends 63 in the transverse direction 10 relative to the central longitudinal axis 7. Each retaining arm 62 is designed in the manner of a leaf spring and has approximately at its center a lash-like locking element 64 on the mounting bracket 1 in a retaining hole 65 of the base part 27 shown in FIG. The contour of the locking element 64 is punched out of the support arm 62 and is connected to the support arm 62 via a leaf spring joint.

FIG. 23 shows the fastening device 1 from FIGS. 21 and 22 according to the section line AB shown in FIG. 22 in a sectional side view prior to the insertion of the clip into the retaining bore 65 of the base part 27. The fastening device 1 is preceded by its clip 61 in FIG Insertion 66 is inserted into the retaining hole 65. Fig. 24 shows the fastening device 1 during the passage of the clip 61 through the retaining hole 65. The fixing tabs are pushed through the retaining hole 65 in the radial direction 10 away from the central longitudinal axis 7 to the side wall 67 of the retaining hole 65 while pushing the clip 61. FIG. 24 also shows that the counter holders 14, starting from the base plate edge 5, are initially fastened to the surface 34 of the base part 27 and are then bent away from this surface 34 again.

FIG. 25 shows the clip 61 pushed into the holding bore 65 in the over-pressed state. The legs of the anvil 14 lie with its attacking on the base plate edge 5 approach 68 flat to the top 34 of the base member 27 at. By this overpressure is ensured that the locking elements 64 seen in the longitudinal direction are completely below the bottom 69 of the plate-like shaped base member 27. Due to their spring elasticity, the locking elements 64 bend in the radial direction 10 back into their initial position, see FIG. 23, to the outside. Thus, the locking elements 64 are in an undercut arrangement to the hole edge region 73 on the bottom 69 of the base part 27th

FIG. 26 shows the fastening device 1 in the final assembled state in the base part 27. The fixation takes place here by means of a positive connection as a result of the described in Fig. 25 undercut arrangement of the locking elements 64 to the hole edge portion 73 out. Due to the double bending of the counter-holder 14 already described, the clip 61 is pulled up slightly in the direction of the central longitudinal axis 7 after being released due to the spring action of the counter-holders 14, so that the fixing tabs lie with their upper side against the underside 69 of the base part 27 , The act on the support arms 62 as arranged tab-like and resilient locking elements 64 ultimately act, as in the already cited manual of the connection technology by Carl-Otto Bauer on page 300 f. is described as a snap connection and snap fix the clip 61 and thus the fastening device 1 in the retaining bore 65 on the base part. Since the axial distance 74 in the direction of the central longitudinal axis 7 from the projection 68 of the counterholder 14 to the upper side 75 of the locking elements 64 is smaller than the thickness 76 of the base part 28, cutting geometry ensures the secure positive locking of the clip 61 in the base part 27.

Furthermore, an attachment 28 is attached to the base part 27 again. The design of the spring arms 6 and arranged on them snapper 9 corresponds to the arrangement described in Fig. 11.

List of Reference Numerals 32 upper edge of the hole

33 bottom

1 fastening device 34 top side

2 snap element 35 top

3 anchorage / screw 36 thickness

4 base plate 38 cone

5 base plate edge 39 knurled bolts

6 spring arm 40 knurling

7 Center longitudinal axis 41 Bolt head

8 Free 42 fret

9 snapper 43 picking cone

10 radial direction 44 cup-like indentation

11 acute angle 45 recording room

12 guide surface 46 clamping wedge

13 turn 48 lobes

14 counterholder 49 conical contour

15 obtuse angle 50 cover plate

16 counterholder surface 51 plate holder

17 free space 52 unlocking opening

18 bore 53 seal

19 nose-like recess 54 gasket receptacle

20 screw head 55 spacer sleeve

21 head end 56 first flange

22 screw longitudinal axis 57 second flange

23 screw shaft 58 retaining bolts

24 screw flange 59 sleeve-shaped holding part

25 external thread 60 additional component

26 undercut 61 clip

27 base part 62 holding arm

28 Article 63 Introduction

29 Through hole 64 Locking element

30 attachment direction 65 retaining hole

31 Lower hole edge 66 insertion direction Side wall

approach

bottom

inner thread

retaining element

poetry

Hole edge region

distance

top

thickness

Claims

claims

1. fastening device (1) for sound-decoupled fixation of an attachment (28) on a base part (27) • with an anchorage (3, 39, 58, 61) on a fixing element for pre-assembly on

Base part (27) and

• with a snap element (2) for snap fixation of the attachment (28) facing away from the free end Fixiert characterized in that the snap element (2) at least one effective as a force storage and a snapper (9) supporting the spring arm (6) and at least one resilient counter-holder (14), in such a way that snapper (9) and counterholder (14) form a free space (17) for receiving a portion of the attachment (28) between them.

2. Apparatus according to claim 1, characterized by a resilient sheet metal bent part as a snap element (2).

3. Apparatus according to claim 1 or 2, characterized by a snap element (2) having a planar base plate (4).

• with one or more of the base plate edge (5) substantially vertically projecting spring arms (6) arranged on their the base plate (4) free ends (8) arranged snappers (9) and

• with one or more of the base plate edge (5) in the direction of the snapper (9) projecting counter-holders (14) with a plane of the base plate (4) substantially uniformly extending counter-holder surface (16).

4. Apparatus according to claim 3, characterized in that the snapper (9) is bent out of the free end (8) of the spring arm (6) s such that the spring arm (6) has a long leg and the snapper (9) has a short leg form an acute angle (11).

5. The device according to claim 4, characterized in that the snapper (9) has a guide surface (12) in its region adjoining the spring arm (6) at an acute angle and has a bend (13) facing away from the spring arm (6) ,

6. Apparatus according to claim 5, 5 characterized by a spring arm (6) extending substantially at right angles bend (13) as an undercut for locking the snap element (2) on the attachment (28).

7. Apparatus according to claim 5, characterized by a to the guide surface (12) perpendicularly extending bend (13) for forming a Entriegelungsschräge for the snap element (2).

8. Device according to one of the preceding claims, 5 characterized in that the width of the spring arms (6) at its free end (8) is greater than the maximum distance of the free ends (8) of two adjacent spring arms (6).

9. Apparatus according to claim 1, characterized by a snap element (2) with a substantially flat base plate (4), with at least one edge on the base plate (4) by means of a Blattfederge- Lenks mounted spring arm (6) and with a pivotal drive for the spring arm (6) effective, in the snap element (2) insertable clamping wedge (46).

10. The device according to claim 9, characterized in that the clamping wedge (46) carries on its in the final assembly state the snap element (2) facing away from a cover plate (50).

11. Device according to one of the preceding claims, characterized by an integral snap element (2).

12. Device according to one of claims 1 to 10, characterized by a two-part snap element (2)

• with a substantially flat base plate (4) and on the base plate (4) arranged at the edge spring arms (6) either by means of a leaf spring joint or as vertically projecting spring elements (6) and

• With a separate preferably designed as a seal resilient see component as an anvil.

13. Device according to one of the preceding claims, characterized by a bolt (3,39) as anchoring.

14. The apparatus according to claim 13, characterized in that the bolt (3) carries an external thread (25).

15. The apparatus according to claim 13, characterized in that in the bolt (39) has an outer contour, in particular a knurling (40) is introduced.

16. The apparatus according to claim 13, characterized in that the bolt (58) is part of a from a bolt-shaped fixing part and s a sleeve-shaped holding part (59) captively assembled assembly unit.

17. The device according to claim 2 with a base plate (4) having a receiving bore (18) for formschlϋssigen o connection of the anchorage (3,39,58) with the snap element (2).

18. Device according to claim 17 in conjunction with one of claims 13 to 16, characterized in that the bolt (3, 39, 58) is pushed through the receiving bore (18) for a positive connection with the snap element (2).

19. Device according to one of claims 1 to 12, characterized by 0 an integral configuration of the anchorage (61) and the snap element

(2) as a resilient sheet-metal bent part such that a base plate (4) carries at least one spring arm (6) and at least one counter-holder (14), which protrude from the base plate (4) in one direction and from the base plate (4) in opposite Direction at least one support arm (62) protrudes to

25 anchoring to the base part (27).

20. The apparatus according to claim 19, characterized by a locking element (64) on the support arm (62) for fixing the anchoring so (61) on the base part (27).

21. The device according to claim 20, characterized in that the axial distance (74) in the direction of the central longitudinal axis (7) from the projection (68) of the counter-holder (14) to the top (75) of the locking elements (64) is smaller than the thickness (76 ) of the base part (27).

22. Connecting arrangement with a fastening device (1) according to one of the preceding claims, characterized by

A pre-assembly position with anchoring fixed to the base part (27) (3, 39, 58) and

• An assembly end position in which the snap element (2) passes through a through hole (29) in the attachment (28) such that the attachment (28) rests with its underside (33) on the counter holder (14) and the catch

(9) with the top (35) of the cap (28) is engaged.

23. A connection arrangement according to claim 22 with a fastening device (1) according to claim 10, characterized by a cup-like indentation (44) in the region of the through hole (29) in the attachment (28) such that with the snapper (9) in the final assembly position in Engaging bore edge below the main plane of the attachment (28) extends to provide a receiving space (45) for the cover plate (50) on the clamping wedge (46).

24. Connecting arrangement according to claim 22 or 23 with a fastening device (1) according to claim 14, characterized by o a captive with the fastening device (1) connected spacer sleeve

(55) between the top of the base and the bottom of the top.

25. Connecting arrangement according to one of claims 22 to 24 with a fastening device (1) according to one of claims 13 to 18, characterized in that the anchorage (3, 39, 58) is screwed into the base part (27) in the pre-assembly position or is fitted.

26. Connecting arrangement according to one of claims 22 to 24 with a fastening device (1) according to one of claims 19 or 20, characterized by a snap connection between anchoring (61) and base part (27) with in particular one via a leaf spring joint with the anchoring (61). connected leaf spring as the base part geschnapptes locking element (64).