Assembled Brake Disc for a Disc Brake With Partial Lining

The present invention relates to an assembled brake disc for a disc brake with partial lining in which the connection between the brake ring and the hub is accomplished via a dog connected to one part and extending into a groove provided at the respective opposite part of the brake disc and whereby the dog rests at radial groove side walls extending essentially parallel to the axial direction of the brake disc.

It is known from German Offenlegungschrift 24 26 952, especially FIGS. 4 and 5, to provide a wedge-shaped bar which is inserted simultaneously into a groove at the brake disc and into a corresponding groove at the hub. In identical grooves two of the bars are fastened two of the bars with screws such that the brake disc connected to the hub. The disadvantage of this construction is that the expenditure during the manufacture of the two grooves in the two components brake ring and hub is considerable since otherwise one or the other side wall of the groove, respectively, contact surface of the wedge will not rest at the corresponding surface of the other part which, in return, results in a great surface pressure of the contacting surface areas causing great wear.

It is therefore an object of the present invention to avoid the disadvantages of the known construction and to provide a design for the dog and the groove such that a tight connection between the dog of one part and the groove of the other part results for all desired connections of a brake disc and furthermore to prevent out-of-trueness of the brake ring after assembly.

This object, and other objects and advantages of the present invention, will appear more clearly from the following specification in conjunction with the accompanying drawings, in which:

FIG. 1 is a concentric cross-sectional view through a connection between the hub and the brake rings;

FIG. 2A shows a concentric cross-sectional view along the line II--II of FIG. 2B;

FIG. 2B is a side view of a connection between the brake ring and the hub;

FIG. 3 is a cross-sectional view along the line II--III of FIG. 4; and

FIG. 4 is a side view of a connection of a brake ring and hub according to FIG. 3.

The assembled brake disc for a disc brake with partial lining according to the present invention is primarily characterized by the brake disc comprising two components in the form of a brake ring and a hub and at least one dog and at least one corresponding groove, the components being connected to one another by the dog extending into the groove, the dog having outer contact surfaces resting at mating inner side walls of the groove, with at least one of the outer contact surfaces and a corresponding one of the mating inner side walls being slanted relative to an axial direction of the brake disc, and further comprising screws extending parallel to the axial direction for pressing the outer contact surfaces against the mating inner side walls.

In a preferred embodiment the dog is comprised of a main body and an additional wedge-shaped part, whereby the additional wedge-shaped part has the slanted outer contact surface, and whereby the brake disc further comprises a pressure spring for pressing the additional wedge-shaped part between the main body and the mating inner side walls of the groove.

It is advantageous that the hub is provided with radially extending arms and the groove is in the form of a recess provided between the arms, whereby the mating inner side walls are slanted, and whereby the arms are connected to the brake ring with the aforementioned screws.

It is furthermore possible to provide the brake ring at a backside thereof with projections forming therebetween a recessed portion for receiving the dog, whereby the dog rests in the recess of the arms and in the recessed portion between the projections of the brake ring.

In another embodiment, the brake disc further comprises concentric annular segments, with the groove being formed between adjacent ones of the segments, whereby the segments have at free ends thereof slanted faces forming the mating inner wall surface of the groove. The dog has a flat bottom portion resting on the hub and a trapeze-shaped top portion, with slanted sides of the trapeze-shaped top portion forming the outer contact surfaces and resting at the slanted faces of the segments.

The advantage of the inventive embodiments of the connecting parts in the form of a dog and a groove for fixedly connecting a brake ring to a hub is that exterior forces acting on the brake ring may be transmitted in a simple manner without any disadvantageous effects from the brake ring to the hub.

The present invention will now be described in detail with the aid of several specific embodiments utilizing FIGS. 1 through 4.

FIG. 1 shows a radial groove 11 which is formed between arms 12 and 13 of a hub and a dog comprising a main part 14 and an additional wedge-shaped part 18 (wedge) connected to a brake ring. The outer contact surface 15 of the main part 14 extends radially and parallel to the axial direction of the brake ring. On the opposite side of the main part 14, the mating inner side wall 16' of the arm 13 is slanted. Between the contact 17 of the main part 14 which extends essentially parallel to the axial direction and the slanted mating inner side wall surface 16' of the arm 13 the wedge 18 with an outer contact surface 16 is forced against the mating inner side wall 16' and the contact surface 17 of the main part 14 by the pressure spring 19 as long as sufficient space is provided for this action. The abutment 20 for the spring 19 is held in place by a screw 21 which extends through the main part 14 and is essentially parallel to the axial direction. The screw 21 also fastens a securing element 22 at the opposite end of the main part 14 which covers the entire groove 11. The abutment 20 is big enough to cover the entire groove 11 and also acts as a securing means. Of course, it is also possible to provide two wedges 18 on either side of the main part 14. The pressure spring 19 forces the wedge 18 between the mating inner side wall 16' of the groove 11 and the contact surface 17 of the main part 14 to such an extent that the main part 14 is fixedly held within the groove 11. When due to wear the full contact of the mating inner side wall 16', the outer contact surface 16 and the contact surfaces 17 and 15 is no longer provided the wedge 18 is automatically forced by the spring 19 between the main part 14 and the arm 13 so that the main part 14 is again fixedly anchored within the groove 11.

According to the FIGS. 2A and 2B the dog 24 is a separate, radially extending part and is provided with two radially extending slanted outer contact surfaces 25 and 26. The hub 28 is provided with a recess 27 having mating inner side walls 26', 26'. The end of the dog 24 which is facing the brake ring 29 rests with further slanted surfaces 30 in a recessed portion provided between projections 31 of the back side of the brake ring 29. The brake ring 29 and the hub are connected to one another by two screws 32 which are arranged on either side of the recess 27 and which extend essentially parallel to the axial direction. The screws 32 extend into the brake ring 29. Due to the slanted outer contact surfaces 25, 26, the brake ring 29 is fixedly connected to the arms 33 of the hub. Occurring manufacturing tolerances may be compensated by the play of the screws 32.

The embodiment according to FIGS. 3 and 4 is comprised of a dog 35 which has a flat bottom portion 36 resting at the hub 37 and a trapeze-shaped top portion 45. With this embodiment it is possible to provide the dog 35 as an integral part of the brake ring. Furthermore, concentric annular segments 39, 40 are provided whereby the free ends of the segments have slanted faces 41, 42 corresponding to the slanted sides 38 (outer contact surfaces) of the trapeze-shaped top portion 45 of the dog 35. Neighboring ones of the concentric annular segments form between them the groove 44 and the slanted faces 41, 42 form the respective mating inner wall surfaces of the groove 44. Each segment thus contacts two dogs 35. The segments are connected to the hub 37 with screws 43 which extend essentially in the axial direction of the brake disc.

In this embodiment as in all other embodiments of the present invention, the number of the dogs may be selected as desired and thereby conformed to respective design requirements. The advantage of the last mentioned embodiment is that when only one segment is provided at the wheel the function of the brake disc is reduced to some extent but is never completely lost.

The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.