DE20306587U1 - Holding clamp is for fixture of gas feed cylinder to airbag and involves two clamps each with clamp rim connected with press-in screw - Google Patents

Abstract

The holding clamp is for the fixture of a gas feed cylinder (1) to an airbag and involves two clamps (2) each with a clamp rim (3) connected with a fixture component (4) in the form of a press-in screw (5). The screw has a thread on which a nut or several nuts can be screwed. This enables the holding clamps to be fixed to the chassis of the vehicle or to other vehicle parts. The clamp rim is formed as a metal plate band, which has a basic area with a hole through which the press-in screw engages. The press-in screw has a head which locates inside the clamp rim. By means of a collar which locates on the outside of the clamp rim in the region of the basic area, the press-in screw is held uncloseably on the clamp rim.

Description

Dr. jur. Alf-Olav Gleiss · Dipl.-Ing. · PA Rainer Große - Dipl.-Ing. ■ PA Dr. Andreas Schrell - Dipl.-Biol. - PA

Torsten Armin Krüger ■ Attorney Nils Heide Attorney at Law Armin Eugen Stockinger - Attorney

Georg Brisen · Dipl.-Ing. ■ PA Erik Graf v. Baudissin - RA

PA: Patent Attorney · European Patent Attorney

European Trademark Attorney RA: Lawyer · Attorney-at-law · Admitted for Representation at the EU-Trademark Office (OHIM), Alicante

Gie'iss & G'roße

Patent Attorneys ■ Lawyers European Patent Attorneys European Trademark Attorneys

Intellectual Property Law Technology Law

Leitzstrasse 45 D-70469 Stuttgart Telephone: +49 (0)711 99 3 11-0 Fax: +49 (0)711 99 3 11-200 E-Mail: office@gleiss-grosse.com Homepage: www.gleiss-grosse.com

In cooperation with Shanghai Zhi Xin Patent Agency Ltd.

Shanghai - China

Utility model application Retaining clamp Hans Oetiker AG Machine and equipment factory Oberdorfstrasse 21

CH-8812 HORGEN

18196t GR-It
22 April 2003

'Gl'eiss& Große

Patent Attorneys - Lawyers European Patent Attorneys European Trademark Attorneys

Intellectual Property Law Technology Law

Description

The invention relates to a retaining clamp for fastening objects, in particular gas storage cylinders for airbags.

According to the invention, a holding clamp is used to fasten objects, which is preferably designed as a stamped sheet metal part and has a circumferential clamping ring. A fastening means, in particular a press-in screw, is arranged on the clamping ring, with which the holding clamp can be fastened. In the case of holding gas storage cylinders for airbags, in particular side airbags, for vehicles, the holding clamp is fastened to a suitable vehicle part, for example to the chassis or to the door structure, by means of the press-in screw.

The arrangement is such that the clamp wraps around the object with a clamping ring, the wrapping leading to radial forces that hold the object in a clamping manner. In order to generate a sufficiently large holding effect between the holding clamp, in particular the clamping ring, and the object according to the invention, a roughening is formed at least in some areas on at least one contact surface with which the holding clamp rests on the object to be held. This roughening makes it possible to hold the object securely. This is particularly important in vehicle construction, since even in the event of an accident deformation of the vehicle, the gas storage cylinder, which can represent the object to be held, must be held securely in order to activate an associated airbag.

The drawings illustrate the invention using exemplary embodiments, and Figure 1 shows a gas storage cylinder 1 which is held by means of two holding clamps 2. Each holding clamp 2 has a clamping ring 3 which is connected to a fastening means 4 in the form of a press-in screw 5. The

18196b GK-It ·· ··· . . . · . ···· . . I

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Press screw 5 has a thread onto which a nut (not shown) or several nuts (not shown) can be screwed. In this way, the retaining clamp can be attached to the chassis of a vehicle or to other vehicle parts.

Figure 2 shows an embodiment of a retaining clamp 2. The clamping ring 3 is - as in all embodiments of this application - designed as a sheet metal strip 6. The retaining clamp 2 is therefore a sheet metal part, in particular a stamped sheet metal part. The fastening means, in particular the press-in screw 5, is designed separately from this stamped sheet metal part and, after the clamping ring has been produced, is firmly connected to it by compression or pressing. The sheet metal strip 6 has a base region 7 which has an opening 8 through which the press-in screw 5 passes. The press-in screw 5 has a head 9 which lies inside the clamping ring 3. The press-in screw is held captive on the clamping ring 3 by means of a compression collar (not shown in detail) which lies on the outside of the clamping ring in the area of the base region 7.

Starting from the base region 7, the sheet metal strip 6 runs diagonally upwards according to Figure 2 and then merges into a curve 10. This is followed - diametrically opposite the base region 7 - by a clamping means 11, which is essentially formed by a U-shaped zone 12 of the clamping ring 3 (in Figure 2, the U-shaped zone 12 is upside down). For mechanical stiffening, the base 13 of the U-shaped zone 12 has at least one inward-facing stiffening web 14, which is produced in particular by embossing the sheet metal strip 6. It can be seen from Figure 3 that two such stiffening webs 14 are formed on the base 13.

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For assembly, one or two retaining clamps 2 are pushed axially onto the gas storage cylinder 1, as shown in Figure 1. In order to clamp the gas storage cylinder 1 into the respective clamping ring 3, the clamping means 11 is deformed as shown in Figure 4 using suitable deformation pliers, i.e. the two legs of the U-shaped zone 12 are pressed towards one another at their ends, whereby the base 13 deforms together with the stiffening webs 14, as shown in Figure 4. In this way, an elastic clamping force is exerted on the object to be held, namely the gas storage cylinder 1. The inner side 15 of the sheet metal strip 6 rests against the gas storage cylinder 1 with a contact surface 16, which is provided with a roughening 17 overall or at least in some areas. The surface roughness is preferably at least 1 pm. One such contact surface 16 can be provided, or several contact surfaces 16 can be formed on a retaining clamp 2.

Figure 3 shows the retaining clamp 2 in a sectional side view.

Figures 4 and 5 show the retaining clamp 2 in the deformed state, i.e. after the axial insertion and clamping of the gas storage cylinder 1, which, however, is not shown in Figures 4 and 5 for the sake of simplicity.

Figures 6 to 8 show a further embodiment of a retaining clamp 2, which essentially corresponds to the embodiment of Figures 4 and 5. The only difference is that a stiffening bead 18 is formed in the area of each of the two arches 10. The bead protrudes slightly outwards, approximately 0.3 mm, as can be seen from Figure 8. It only extends over a partial angle of the circumferential sheet metal strip 6. The bead improves the clamping force on the gas storage cylinder 1, since it has a mechanically strengthening effect and brings with it a corresponding pre-tensioning effect in the elastic range.

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Figures 9 and 10 show a further embodiment of a holding clamp 2, in which in the upper area of the encircling sheet metal strip 6, bulges 19 in the form of convex arches 20 are formed. While the stiffening webs 14 already mentioned above in the other embodiments run in the circumferential direction of the sheet metal strip 6 and the stiffening beads 18 also extend in the circumferential direction of the sheet metal strip 6, the bulges 19 form arches 20, the apex lines of which run transversely to the sheet metal strip 6. The respective arch itself extends in the direction of the sheet metal strip 6. The bulges 19 improve the elastic clamping effect on the gas storage cylinder 1 to be held.

Figures 11 and 12 show a further embodiment of a holding clamp 2 in which - in contrast to the embodiment of Figures 9 and 10 - two further crowns 19 are provided, which are located in the lower half of the sheet metal strip 6 (see Figure 11).

Figures 13 to 15 show a final embodiment of a retaining clamp 2, in which the sheet metal strip 6 is not flat, at least in the area of the bends 10 - or alternatively also all the way around - according to Figure 15, but is convexly curved outwards (radius R80). The sheet metal strip 6 therefore runs slightly curved - seen in the insertion direction 21 (Figure 14). This also improves the elasticity and leads to a better holding force.

Figures 16 to 18 show a final embodiment of a retaining clamp 2, in which the sheet metal strip 6 in the area of each of the two approximately diametrically opposed arches 10 has, in addition to a stiffening bead 18, which has already been shown and described in the embodiment of Figures 6 to 8, slight flanges 22 in the direction of the imaginary center of the clamping ring 3. The flanges 22 extend along both edges of the sheet metal strip 6.

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bands 6 over a partial angle α of the circumferential sheet metal band 6. The partial angle α is in particular between 30° and 120°, preferably between 60° and 100°. The stiffening bead 18 and the flanges 22 lying parallel to and on both sides of it on each clamping ring side maintain a distance from both the base area 7 and the clamping means 11 in the bilateral continuations of the respective arc of the partial angle α. The stiffening bead 18 and the flanges 22 increase both the rigidity and the clamping effect of the holding clamp 2.

All embodiments of Figures 1 to 18 have in common that - as already described in the embodiment of Figures 2 and 3 - the inner side 15 of the sheet metal strip 6 is provided with a roughening at least in some areas, so that the contact surface facing the object to be held, in particular the gas storage cylinder 1, has the surface roughness completely or in some areas and in this way a secure hold of the object to be clamped is ensured.

Figures 19 to 22 show a further embodiment of a retaining clamp 2, wherein Figure 19 shows the retaining clamp in the state as a substantially flat sheet metal strip 6. The same applies to Figure 20. In Figure 21, the retaining clamp 2 is made into a ring shape, but is not yet provided with a press-in screw. Figure 22 shows - in an enlarged view - the upper area of Figure 21 of the retaining clamp 2.

The clamping ring 3 of the essentially still flat holding clamp 2 has a punched opening 30 in one end area in Figure 19, to which a preferably approximately square depression 31 is connected on one side. In the area of the other end, the clamping ring 3 has an opening 32 into which a tongue 33 formed in one piece with the clamping ring 3 protrudes like a nose. The opening 32 is connected on one side to a depression 34.

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which preferably has an approximately square shape. The depressions 31 and 34 lie above the plane of the outer side 35 of the clamping ring 3 (see also Figure 20). The tongue 33 lies with its free end in a plane which lies below the plane of the inner side 36 of the sheet metal strip 6. The cross-sectional shape of the clamping means 11 can also be clearly seen from Figure 20. The clamping means 11 has an M-shape in the central longitudinal plane due to a stiffening web 14 which is introduced there and which has a stadium-shaped design when viewed from above. Furthermore, the pressing direction (arrow 37) of the press-in screw 5 can be seen from Figure 20. The head 9 of the press-in screw 5 is not designed as a round head, but as a head with at least one anti-twisting edge 38. Figures 30, 31 and 32 show top views of the head 9 of various press-in screws 5, with Figure 30 showing a head contour that is circular over a large part of the circumference and then has a secant-like anti-twist edge 38. The head contour of Figure 31 has two diametrically opposed, arcuate areas 39 and two straight areas that are also diametrically opposed to one another, which form anti-twist edges 38. In Figure 32, the head 9 has a hexagonal contour, so that a total of six anti-twist edges 38 are formed.

Figure 21 shows that the two end areas of the clamping ring 3 do not overlap in the area of the press-in screw 5 and are held together there by the press-in screw 5, as was the case in the previous embodiments, but that the tongue 33 is introduced into the opening 30 to hold the ring shape together and that then - by widening the ring - the tongue 33 engages behind the recess 31. In this way, a lock 42 is created for the clamping ring 3, whereby the plane of the tongue 33 does not protrude into the interior of the ring, since the corresponding free space for the tongue 32 is created by the recess 31. The recess 34

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has a stiffening effect and, due to the free space created by it, also allows the depression 31 to enter when the tongue 33 is inserted into the opening 30. From Figures 21 and 22 it can be seen that the press-in screw 5 is pressed with its shaft into an opening 40 in the clamping ring 3, which is surrounded by an outwardly directed annular bead 41. As a result of the pressing in of the press-in screw 5 and the possible at least partial leveling of the annular bead 41, a tight fit of the edge of the opening 40 on the shaft of the press-in screw 5 is achieved.

Figures 23 to 25 show a further embodiment of a retaining clamp 2, wherein Figure 23 corresponds to Figure 19, Figure 24 to Figure 20, Figure 25 to Figure 21 and Figure 26 to Figure 22 of the previously described embodiment. In the following, only the differences between the embodiment of Figures 23 to 25 and the embodiment of Figures 19 to 22 will be discussed. From Figure 22 it can be seen that instead of one stiffening web 14 (Figure 19), two stiffening webs 14 are provided, which - viewed across the width of the ring - lie next to one another. Another difference is that an approximately cylindrical cup wall 43 adjoins the annular bead 41 in the area of the opening 40. From the cup wall 43 it transitions into the ring shape of the clamping ring 3, forming a kink 44 in each case. In Figure 22 of the previously described embodiment, however, the ring contour begins relatively close to the annular bead 41, i.e. there is no cylindrical region.

Figures 27 and 28 show retaining clamps 22 with a pressed-in press-in screw 5, whereby the embodiment of Figure 27 corresponds to the design according to Figures 19 to 22 and the embodiment of Figure 28 corresponds to the embodiments of Figures 23 to 26. It is clearly visible that in the embodiment of Figure 27 the head 9 of the press-in screw 5 is in an area 45 of the

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clamping ring 3, which is essentially flat below the head 9 and from there merges into the ring contour by means of a bent, approximately flat area 46. In contrast to this, in the embodiment of Figure 28 it can be seen that the head 9 is surrounded by the pot wall 43 on the wall side, so that the head 9 is essentially in a recessed pot. From there it merges directly into the arched design of the clamping ring 3 via corresponding bend zones 47.

In the embodiments of Figures 27 and 28, it is always ensured that the head 9 of the press-in screw 5 has at least one anti-twist edge 38, which is acted upon by the inner side 36 of the clamping ring 3, so that the press-in screw 5 is held against twisting. The inner side 36 of the clamping ring 3 therefore interacts with at least one anti-twist edge 38, preferably with two anti-twist edges 38 that are diametrically opposed to one another, of the head 9, so that even when very large torques are applied, twisting is prevented when screwing a securing element, for example a nut, onto the threaded shaft of the press-in screw 5.

Figure 29, which corresponds to Figure 27, shows how the clamping means 11 is deformed when the retaining clamp 2 is secured. Using a suitable tool, the initially approximately U-shaped area of the clamping means 11 is grasped and then pressed inwards on both sides (arrows 48), so that the shape shown in Figure 29 is obtained. This reduces the diameter of the clamping ring, so that an object located in it is held in a clamped manner. In the embodiments of Figures 27 and 28, the top of the head 9 of the press-in screw 5 is always recessed so far that a clamped round or circular cylindrical object cannot be subjected to force or can only be subjected to a maximum of normal force.

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is struck. The "normally large" force is the force that also acts in the other zones of the clamping ring 3.

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Claims (5)

1. Retaining clamp ( 2 ) for fastening objects, in particular gas storage cylinders ( 1 ) for airbags, with a clamping ring ( 3 ) which wraps around the object and which clamps around the object in particular by means of mechanical assembly deformation (clamping means 11 ) and thereby rests against the object with at least one contact surface ( 16 ), wherein the contact surface ( 16 ) is provided at least in regions with a roughening ( 17 ) which improves the holding effect between the retaining clamp ( 2 ) and the object. 2. Retaining clamp according to claim 1, characterized by the design as a sheet metal part. 3. Retaining clamp according to one of the preceding claims, characterized in that the roughening has a surface roughness of at least about 1 µm. 4. Holding clamp ( 2 ) for fastening objects, in particular gas storage cylinders ( 1 ) for airbags, with a substantially ring-shaped clamping ring ( 3 ) which wraps around the object and clamps around the object in particular by means of mechanical assembly deformation (clamping means 11 ), and with a clamp fixing bolt (press-in screw 5 ) which passes through an opening ( 40 ) of the clamping ring ( 3 ) and has a head ( 9 ) located inside the clamping ring ( 3 ), characterized in that the head ( 9 ) has at least one anti-twisting edge ( 38 ) which is arranged opposite the inside ( 36 ) of the clamping ring ( 3 ) to block the rotation of the clamp fixing bolt (press-in screw 5 ). 5. Retaining clamp according to claim 4, characterized in that the head ( 9 ) of the clamp fastening bolt (press-in screw 5 ) has a polygonal contour.