Patent Application
20130272783
The invention is directed to a fastening device having a fastening clamp formed of one or more parts and shaped from springing flat material for fastening a perforated first thin wall or other thin-walled structural component part to a thin-walled second thin wall or carrier provided with a corresponding perforation, wherein the fastening clamp comprises a head region which, in the assembled state of the clamp, contacts the one side of the one thin wall, which side is remote of the other thin wall, a neck region which proceeds from the body region and projects through the perforations of the two thin walls in the assembled state of the clamp, and a body region which, in the assembled state, proceeding from the neck region, projects beyond the other side of the other thin wall by two opposing step-back surfaces of the flat material which are formed by bending, wherein the step-back surfaces are springingly supported on the hole face, the edge or the edge face of the perforation of the carrier.
It is noted that citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention.
A fastening device of the type mentioned above is known from the Internet publication of A. Raymond GmbH & Co. KG, Teichstr. 57, 79539 Lörrach, see product group CAA, component D, “spring clamps”.
It is noted that in this disclosure and particularly in the claims and/or paragraphs, terms such as “comprises”, “comprised”, “comprising” and the like can have the meaning attributed to it in U.S. patent law; e.g., they can mean “includes”, “included”, “including”, and the like; and that terms such as “consisting essentially of” and “consists essentially of” have the meaning ascribed to them in U.S. patent law, e.g., they allow for elements not explicitly recited, but exclude elements that are found in the prior art or that affect a basic or novel characteristic of the invention.
It is further noted that the invention does not intend to encompass within the scope of the invention any previously disclosed product, process of making the product or method of using the product, which meets the written description and enablement requirements of the USPTO (35 U.S.C. 112, first paragraph) or the EPO (Article 83 of the EPC), such that applicant(s) reserve the right to disclaim, and hereby disclose a disclaimer of, any previously described product, method of making the product, or process of using the product.
It is the object of the invention to provide another design of a spring clamp of the kind mentioned above which is used, for example, in switch cabinets, guard rails, solar installations, automobile construction, etc. to detachably fasten a perforated thin wall to a perforated carrier in order to replace a rigid screw connection by a clamp connection which can be assembled quickly and which is flexible but durable. The spring clamp can be used in automobile construction, in guard rail construction, in solar cell construction and in other fields.
The above-stated object is met in that the two step-back surfaces are formed by two V-shaped spring portions which project beyond the thin walls, and the perforation comprises two adjacent rectangular holes which are separated by a web for receiving the fastening clamp.
A lasting torsional strength and a very strong connection under shear stress are achieved by means of the multiple perforation, particularly by means of the two holes.
According to a further development of the invention, the fastening clamp comprises two legs or branches remote of one another and two branches facing one another; the two branches remote of one another form at the free ends thereof the step-back surface on the one hand and, at a tight angle thereto, a stop face on the other hand for abutting at the hole face of the one rectangle side of the rectangular perforation in the thin wall and the thin-walled wall carrier.
The twofold perforation affords the advantage that the walls which are connected to one another allow displacements because the perforation can be formed of smaller holes which automatically result in reduced bet dab of the wall portions relative to one other. This additional displaceability is limited to half of the extension of the perforation in the direction of movement. Counter to the spring force, the movements perpendicular thereto are allowed only through play, but apart from this there is no possibility of movement in this direction.
According to a further embodiment form of the invention, the two branches facing one another are joined to one another at their free ends and in this connecting region form a head which forms the head region. By forming this head, the arrangement is made even stiffer in the sliding direction and in the direction of spring movement.
According to yet another embodiment form, the mutually facing branches together with the head have a mushroom shape in cross section. This allows the fastening clamp to be pressed into the perforation.
When the head forms a void at its underside and two edges of the head rest on the thin wall in the assembled state, this affords space for the movement of the spring legs during the assembly process and also allows larger clamping areas to be realized with the same clamp (tolerance compensation).
The edge of the head can be bent in a curve having a radius of curvature such that the top of the head can form a planar surface. On the other hand, the top of the head can also form a rounded surface either with a rounded edge cross section or with a sharply bent edge cross section. The head shape affects the appearance as well as handling during assembly and disassembly.
Projections extending away from the mutually facing branches laterally perpendicular to the branch plane can be provided in the neck region, the lateral extension of which completely fills, or only partially fills, the respectively contacting side wall of the perforation and can either receive therebetween and guide the free end of the branches remote of one another or forms an abutment for the stop faces.
The shear strength is increased by providing two additional slots for the perforation perpendicular to the longitudinal extension of the rectangular holes near the ends thereof, these two additional slots being penetrated by projections proceeding from the planar surface of the head of the fastening spring when assembled; only the play determined by the penetrating projections or branches need be taken into account. The branches of the fastening clamp can have a width that is smaller in direction of the connecting web thereof and is virtually conical.
It is to be understood that the figures and descriptions of the present invention have been simplified to illustrate elements that are relevant for a clear understanding of the present invention, while eliminating, for purposes of clarity, many other elements which are conventional in this art. Those of ordinary skill in the art will recognize that other elements are desirable for implementing the present invention. However, because such elements are well known in the art, and because they do not facilitate a better understanding of the present invention, a discussion of such elements is not provided herein.
The present invention will now be described in detail on the basis of exemplary embodiments.
According to the invention, the two step-back surfaces 30, 32 are formed by two V-shaped parts 44, 46, and the perforation 16, 18 for receiving the fastening clamp 12 includes two rectangular holes 50, 52 which are disposed side by side and separated by a web 48.
As is particularly clearly apparent from
The two branches 58, 60 of the fastening clamp 12 which face one another are joined at their free ends and in this connecting region form a head which forms the head region. As can be further seen from the figures, the branches 58, 60 which face one another, together with the head 66, have a mushroom shape in cross section.
The head 66 forms a void 68 at its underside. The two edges 70 of the head 66 rest on the thin wall 14 in the assembled state of the fastening clamp.
In the embodiment form according to
In contrast, the embodiment form according to
In all three embodiment forms, the edge 70, 170, 270 of the head presses on the thin wall 14. In the embodiment form shown in
In the embodiment form according to
In the embodiment form shown in
As is shown in the embodiment form according to
This further increases the shear strength of the arrangement both in direction of the slots and perpendicular thereto.
To facilitate insertion of the fastening clamp into perforation 52, 55, the branches 554, 534 can be constructed conically, see
The invention is commercially applicable in switch cabinet construction.
While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the inventions as defined in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20 2010 012 226.0 | Sep 2010 | DE | national |
The present application claims priority from PCT Patent Application No. PCT/EP2011/004246 filed on Aug. 24, 2011, which claims priority from German Patent Application No. DE 20 2010 012 226.0 Filed on Sep. 6, 2010, the disclosures of which are incorporated herein by reference in their entirety.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP11/04246 | 8/24/2011 | WO | 00 | 3/22/2013 |
