Bellows, and at least one disc brake having a bellows

Abstract

A rotationally symmetrical bellows has a first end ring and a second end ring with a smaller diameter, and multiple folds, which in a relaxed position each have two flanks running in opposite directions with respect to one another while forming a bend. The flanks extend approximately parallel to an axis of rotation of the bellows. The rotationally symmetrical bellows is designed such that in a relaxed position of the bellows, the second end ring is arranged at an axial distance to the first end ring.

Claims

1. A rotationally symmetrical bellows, comprising: a first end ring; a second end ring having a smaller diameter than that of the first end ring; a plurality of folds which, in a relaxed position, each have two flanks extending in opposite directions with respect to one another while forming a bend, the flanks extending approximately parallel to a rotational axis of the bellows, wherein in the relaxed position of the bellows, the second end ring is arranged at an axial spacing from the first end ring, and a flank of the plurality of flanks adjacent to the first end ring is dimensioned such that an adjoining one of the bends terminates at an axial height corresponding to an axial height of an end side of the first end ring which faces away from the second end ring.

2. The rotationally symmetrical bellows as claimed in claim 1, wherein the spacing is at least 8 mm.

3. The rotationally symmetrical bellows as claimed in claim 1, wherein the spacing is from 8 to 18 mm.

4. The rotationally symmetrical bellows as claimed in claim 1, wherein the spacing is from 10 to 15 mm.

5. The rotationally symmetrical bellows as claimed in claim 1, wherein three folds are provided.

6. The rotationally symmetrical bellows as claimed in claim 1, wherein the spacing is defined as a measure between that free end side of the second end ring which forms an upper edge and the facing upper edge of the first end ring.

7. A disc brake for a commercial vehicle for use with a brake disc, comprising: a brake caliper that extends over the brake disc when installed; a brake application device by which a brake pad is pressable against the brake disc via at least one actuating spindle, the actuating spindle having a pressure piece that presses the brake pad; a deformable bellows encloses the actuating spindle between the pressure piece and the brake caliper, wherein the bellows is held via a first end ring in a frictionally locking manner in an outlet opening of the brake caliper or a closure plate having the outlet opening, and by way of a second end ring in a frictionally locking manner on the actuating spindle or the pressure piece, and wherein the second end ring has a smaller diameter than the first end ring of the bellows, the bellows has a plurality of folds which, in a relaxed position, each have two flanks extending in opposite directions with respect to one another while forming a bend, the flanks extending approximately parallel to a rotational axis of the bellows, in the relaxed position, the second end ring is arranged at an axial spacing from the first end ring, and a flank which is assigned to the first end ring is dimensioned such that an adjoining one of the bends terminates at an axial height corresponding to an axial height of an end side of the first end ring which faces away from the second end ring.

8. The disc brake as claimed in claim 7, wherein in the case of non-worn brake pads, the second end ring of the bellows is arranged approximately in a circumferential overlap region with the first end ring, with deformation of at least one part of the flanks and/or the bends.

9. The disc brake as claimed in claim 8, wherein the flanks and the bends have a circular contour in every position of the bellows during operation of the disc brake.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a part of a disc brake in accordance with the prior art, in a sectioned plan view.

(2) FIG. 2 shows a bellows according to an embodiment of the invention in a relaxed position.

(3) FIG. 3 shows the bellows as a detail after assembly into a disc brake having unworn brake pads.

DETAILED DESCRIPTION OF THE DRAWINGS

(4) FIG. 1 shows one half of a disc brake which can be actuated pneumatically or by electric motor and has a brake caliper 1 which is configured as a sliding caliper and reaches over a brake disc 3.

(5) Brake pads 4 are arranged on both sides of the brake disc 3, of which brake pads 4 only one is shown here which can be pressed against the brake disc 3 in the functional case.

(6) The brake pad 4 consists of a pad carrier plate 5 and a friction lining 6 which is fastened on the side which faces the brake disc 3.

(7) In the case of a braking operation, the brake pad 4 is pressed against the brake disc 3 by way of a brake application device 2 which is arranged in the brake caliper 1 and is actuated by a brake lever, an actuating spindle 11 and a pressure piece 7 which bears against the brake pad 4.

(8) In order to compensate for a wear-induced change in the air gap, that is to say the spacing between the friction lining 6 and the brake disc 3, the actuating spindle 11, which is configured as a threaded spindle, is mounted rotatably on the brake caliper 1 and can be moved via an adjusting device (not shown).

(9) In order to protect against weather influences on the functional parts which are arranged in the interior of the brake caliper 1, the brake caliper 1 is closed on its side which faces the brake disc 3 by way of a closure plate 8 which is interrupted in the outlet region of the actuating spindle 11 and forms an outlet opening 10 there.

(10) In order to seal the outlet opening 10, a bellows 9 which is connected to the closure plate 8 is provided, which bellows 9 is connected to the closure plate 8 such that it cannot rotate, and is likewise connected to the pressure piece 7.

(11) As shown very clearly, in particular by FIG. 2 which shows the bellows in a relaxed position, the rotationally symmetrical bellows 9 has a dimensionally stable first end ring 12 and a second end ring 13 of smaller diameter, which end rings 12, 13 are connected to one another by way of a plurality of (in the example, three) folds 14.

(12) With the formation of a bend 16, each fold 14 has two flanks 15 which run in opposite directions to one another and extend approximately parallel to a rotational axis X of the bellows 9.

(13) In the relaxed position of the bellows 9, in accordance with the invention, the second end ring 13 is arranged at an axial spacing “a” from the first end ring 12, the spacing “a” being at least 8 mm, preferably from 8 to 18 mm, and particularly preferably from 10 to 15 mm. Here, the spacing “a” is defined as the axial measure between an upper edge 18 of the second end ring 13 of smaller diameter and the facing upper edge 17 of the first end ring 12.

(14) Here, the height of the flanks 15 which adjoin the first end ring 12 is approximately from 6 to 8 mm.

(15) FIG. 3 depicts a position of the bellows 9, as is produced after an installation into a brake disc in accordance with FIG. 1, to be precise in the case of unworn brake pads.

(16) Here, the second end ring 13 is displaced toward the first end ring 12 to such an extent that the two end rings 12, 13 lie approximately in a circumferential overlap region, whereas the folds 14 or their flanks 15 and bends 16 are deformed, at least partially, but in such a way that circular contours result in every case.

(17) These circular contours are maintained even if the second end ring 13 is pushed out of the overlap region with the first end ring 12 on account of the axial adjustment of the actuating spindle 11, for example as far as an end position, in which the spacing a is 35 mm, with consideration of the spacing a of 15 mm in the relaxed position of the bellows 9, in accordance with FIG. 2. This results overall in a stroke of 50 mm.

LIST OF DESIGNATIONS

(18) 1 Brake caliper 2 Brake application device 3 Brake disc 4 Brake pad 5 Pad carrier plate 6 Friction lining 7 Pressure piece 8 Closure plate 9 Bellows (boot or bellows seal) 10 Outlet opening 11 Actuating spindle 12 End ring 13 End ring 14 Fold 15 Flank 16 Bend 17 Upper edge 18 Upper edge

(19) The foregoing disclosure has been set forth merely to illustrate 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.