Patent Application
20080236960
The present invention relates to a disc brake for a utility or commercial vehicle having a caliper that straddles a brake disc. Functional parts, such as drive parts, of a wear adjustment device, are arranged, in particular, outside the caliper and are encapsulated by a cover fastened exteriorly to the caliper.
A disc brake of this type is known, for example, from DE 103 00 013 A1.
For the functioning of such a disc brake, inter alia, an adjusting device is provided, by which an amount of lifting play between the brake disc and brake pad can be set. The adjustment device is operated, for example, via a synchronous transmission and, for this purpose, has an output gearwheel, which can be driven mechanically or via an electric motor. Both the output gearwheel and electric motor may be arranged inside or outside the caliper, as are further functional parts which are required for operating the disc brake.
For protection against mechanical and climatic or environmental influences, these functional parts are covered by a cover, and to that extent are encapsulated with respect to the surroundings. The cover is connected to the caliper.
This connection has hitherto taken place positively, in particular by screwing, but has the disadvantage that this connection can be released in any event. This type of connection, however, does not provide reliable protection against manipulation, and there is, therefore, the risk that there may be improper or unauthorized access to the functional parts encapsulated by the cover.
Particularly, in the case of repair work which may become necessary, this may present problems which constitute a potential risk to the operating reliability of the disc brake.
Furthermore, the mounting of the cover and, in particular, the preparation of the connection points, is complicated and therefore costly, since threaded bores must be provided in the caliper, which, of course, can be implemented only at considerable outlay in terms of manufacturing costs.
Since such disc brakes are produced as standard parts in large quantities, there is considerable importance in having efficient manufacture, with regard to which the known disc brakes are only an inadequate solution.
The object on which the invention is based, therefore, is to develop further a disc brake of the above-described type such that the cover for encapsulating functional parts is fastened in a manipulation-proof manner. A more cost-effective production and assembly of the cover and disc brake are also possible.
This object is achieved by a disc brake having a caliper that straddles a brake disc. Functional parts, such as drive parts, of a wear adjustment device, are arranged, in particular, outside the caliper and are encapsulated by a cover fastened exteriorly to the caliper. The cover is connected to the brake caliper in a materially integral manner.
A disc brake designed according to the invention affords considerable advantages, as compared with the prior art.
First, on the one hand, the manipulation-proof fastening of the cover must be mentioned, since the materially integral connection, preferably by welding, is possible only as a result of the mechanical destruction of the connection points.
Furthermore, the machining of the caliper for fastening the cover may largely be dispensed with, since connection junctions, such as threaded bores or the like, are no longer required.
Dispensing with preparatory work in this way leads, for obvious reasons, to a reduction in the manufacturing costs, thus resulting in appreciable savings.
Dispensing with connection mechanisms, such as the screws mentioned previously, also leads to a reduction in costs, to which a shorter manufacturing time likewise contributes, since the materially integral connection can be made more quickly than a positive connection.
Owing to the materially integral connection, which, as mentioned, is preferably made by welding, but, in principle, may also take place by adhesive bonding, a transmission of axial and transverse forces is possible, while an improvement in the contact pattern can be achieved by any desired choice of the number of contact points.
Welding may be carried out by way of a laser or welding electrodes. In laser welding, in the bearing region of the cover with respect to the caliper, a plurality of perforations, preferably in the form of bores, are provided, at the inner margin of which a peripheral laser weld seam is generated, by which the welded joint is made.
In welding by way of a welding electrode, the cover bears with a pronounced welding lug or tenon against the brake caliper, while the welding electrode is introduced into a concentric blind hole, which the welding lug adjoins. Welding in this case takes place inductively. It is also contemplated for the caliper to be provided with welding lugs.
In the case of a metal cover, the welding lugs may be introduced by embossing, whereas, in the case of a plastic cover, the respective welding lug is an integral part of a metal ring used which, secured at least axially, is seated in the plastic cover. Metal rings introduced into the plastic cover also serve for connection by way of laser welding, in which case the metal ring is modified correspondingly.
Both welding methods may be automated, that is to say automatic welding of the cover to the caliper can be carried out very efficiently by use of a suitable robot.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description when considered in conjunction with the accompanying drawings.
The cover 1 shown in
The metal rings 3, 4 are mounted so as to be secured axially, and preferably also secured rotationally or against twisting, in the cover 1. For this purpose, a circumferential bead 6 is integrally formed on the metal ring 3, which bead 6 matches positively with the cover 1.
The metal ring 3 is configured such that it can be welded to the brake caliper 2 by way of an electrode 11 (
In the example shown in
So that induction welding with low current intensity can be carried out, the cross section of the lug 5 is kept relatively small, while the selected outside diameter of the metal ring 3 designed as a rotationally symmetrical body is relatively large, so that the metal ring heats up only slightly during welding.
This metal ring 4 is provided with a throughbore 8 and on its end face facing the brake caliper 2 has a bearing ring 9 with which it is supported on the caliper 2.
The metal ring 4 is welded to the brake caliper 2 by laser welding, a laser beam 10 being illustrated diagrammatically in
In this case, welding takes place on the lower inner circumference of a throughbore 8, which forms a transition to the caliper 2 and by melting makes it possible to have a fixed connection of the metal ring 4 and, consequently, of the cover 1 to the caliper 2.
There is, of course, also the possibility of connecting the metal cover 1 to the brake caliper 2 in a materially integral manner by way of laser welding, in which case the cover 1 has bearing rings 9 integrally formed correspondingly.
Since the welding of the cover 1 to the caliper 2 takes place, as it were, in a punctiform manner, a seal 13 is provided peripherally for sealing off the inner space, which receives the functional parts, of the cover 1 with respect to the surroundings. The seal 13 is supported sealingly, on the one hand, on the cover 1 and, on the other hand, on the caliper 2.
The foregoing disclosure has been set forth merely to illustrate one or more embodiments of the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2005 042 796.0 | Sep 2005 | DE | national |
This application is a continuation of PCT International Application No. PCT/EP2006/008672, filed on Sep. 6, 2006, which claims priority under 35 U.S.C. §119 to German Application No. 10 2005 042 796.0, filed Sep. 8, 2005, the entire disclosures of which are expressly incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP2006/008672 | Sep 2006 | US |
| Child | 12044542 | US |
