DISC BRAKE FOR A MOTOR VEHICLE

Abstract

A disc brake (1) includes a brake disc (2), a brake caliper (3), two brake pads (4, 4′) that are movably guided on the brake caliper (3), a retainer spring (6, 6′) on each brake pad (4, 4′), a retainer bracket (8-8.sup.IV) for pre-tensioning the retainer springs (6, 6′) in relation to the respective brake pad (4, 4′), and an expander spring (10, 10′) that applies an expansion force between the brake pads (4, 4′) and diverging the brake pads (4, 4′). The ends of the expander spring (10, 10′) may bear in each case directly on one of the retainer springs (6, 6′). The disc brake (1) may have a loss prevention device that is operatively connected to the expander spring (10, 10′) such that the expander spring (10, 10′), in the absence of the expansion force, is held on the disc brake (1).

Claims

1. A disc brake (1) for a motor vehicle, in particular for a commercial vehicle, comprising: a brake disc (2); a brake caliper (3); two brake pads (4, 4′) on both sides of the brake disc (2), the brake pads movably guided on the brake caliper (3); a retainer spring (6, 6′) on each brake pad (4, 4′); a retainer bracket (8-8.sup.IV) for pre-tensioning the retainer springs (6, 6′) in relation to the respective brake pad (4, 4′); and an expander spring (10, 10′) that applies an expansion force in an effective direction between the brake pads (4, 4′) and diverging the brake pads (4, 4′); wherein the ends of the expander spring (10, 10′) bear in each case directly on one of the retainer springs (6, 6′).

2. The disc brake as claimed in claim 1, wherein the expander spring (10, 10′) on each end thereof has a holding portion (18, 18′) that can be brought in contact with the retainer springs (6, 6′).

3. The disc brake as claimed in claim 2, wherein each holding portion (18, 18′) is integrally molded in an end portion of the expander spring (10, 10′) and encompasses the retainer spring (6, 6′) at least partially.

4. The disc brake as claimed in claim 2, wherein the holding portion (18, 18′) is disposed outside the center of mass of the expander spring (10, 10′).

5. A disc brake (1) for a motor vehicle, in particular for a commercial vehicle, comprising: a brake disc (2); a brake caliper (3); two brake pads (4, 4′) on both sides of the brake disc (2), the brake pads movably guided on the brake caliper (3); a retainer spring (6, 6′) on each brake pad (4, 4′); a retainer bracket (8-8.sup.IV) for pre-tensioning the retainer springs (6, 6′) in relation to the respective brake pad (4, 4′); and an expander spring (10, 10′) that applies an expansion force in an effective direction between the brake pads (4, 4′) and diverging the brake pads (4, 4′); wherein the disc brake (1) includes a loss prevention device operatively connected to the expander spring (10, 10′), wherein the expander spring (10, 10′) in the absence of the expansion force is held on the disc brake (1).

6. The disc brake as claimed in claim 5, further comprising a guide part (20-20′″) that receives the expander spring (10, 10′) and at least partially guides the expander spring in the effective direction of the expansion force.

7. The disc brake as claimed in claim 6, wherein the guide part (20-20′″) is configured as a bar element and is at least partially surrounded by the expander spring (10, 10′).

8. The disc brake as claimed in claim 6, wherein the guide part (20) and the expander spring (10, 10′) are disposed in a clearance (22) of the retainer bracket (8) and movable at least in the effective direction of the expander spring (10, 10′).

9. The disc brake as claimed in claim 6, wherein the guide part (20′-20′″) has at least one first guide mandrel (24-24″) which is disposed on the retainer bracket (8′-8.sup.IV) and extends in a clearance (22′) on the retainer bracket (8′-8.sup.IV).

10. The disc brake as claimed in claim 9, wherein the guide mandrel (24-24″) is a first guide mandrel, and the guide part (20′-20′″) in addition to the first guide mandrel (24-24″) has a second guide mandrel (26-26″), wherein the first guide mandrel (24-24″) and the second guide mandrel (26-26″) extend toward one another from opposite ends of the retainer bracket (8′-8.sup.IV), wherein the first guide mandrel (24, 24″) and the second guide mandrel (26, 26″) have dissimilar lengths.

11. The disc brake as claimed in claim 10, wherein at least one end (14, 14′) of the expander spring (10′) has a slide (40, 40′) which is movable along the guide part (20″, 20′″) and covers a spacing (X.sub.1) between the first guide mandrel (24″) and the second guide mandrel (26″).

12. The disc brake as claimed in claim 10, wherein the first guide mandrel (24, 24′) and the second guide mandrel (26, 26′), for inserting the expander spring (10, 10′), terminate at a mutual spacing (X), the spacing (X) between the ends of the first and the second guide mandrel (24, 24′, 26, 26′) being smaller than a block length (L.sub.B) of the expander spring.

13. The disc brake as claimed in claim 10, further comprising a mating part (30) which, has mountings (32) that fasten to the first and the second guide mandrel (24, 24′, 26, 26′) for connecting the ends of the first and the second guide mandrel (24, 24′, 26, 26′).

14. The disc brake as claimed in claim 10, wherein at least the first or the second guide mandrel (24″, 26″) is movable in a reciprocating manner between an operating position and an assembling position for assembling the expander spring (10, 10′).

15. The disc brake as claimed in claim 2, further comprising a cover (34) which is specified for at least in portions covering the expander spring (10, 10′) on the retainer bracket (8-8.sup.IV).

16. The disc brake as claimed in claim 15, wherein the cover (34) is part of a protective cap (38) that shields the brake caliper (3) on the upper side thereof.

17. The disc brake (1) as claimed in claim 2, wherein the ends of the expander spring (10, 10′) bear in each case directly on one of the retainer springs (6, 6′).

18. The disc brake (1) as claimed in claim 1, wherein the disc brake (1) includes a loss prevention device operatively connected to the expander spring (10, 10′), wherein the expander spring (10, 10′) in the absence of the expansion force is held on the disc brake (1).

19. The disc brake (1) as claimed in claim 1, further comprising a guide part (20-20′″) that receives the expander spring (10, 10′) and at least partially guides the expander spring in the effective direction of the expansion force

20. A kit for a brake caliper of a disc brake having brake pads on both sides of the brake disc thereof, comprising: a retainer bracket (8-8.sup.IV) for pre-tensioning retainer springs (6, 6′) of the brake pads; and an expander spring (10, 10′) for applying an expansion force in an effective direction between the brake pads and for diverging the brake pads, the ends of the expander spring configured for being brought to bear in each case directly on a retainer spring (8-8.sup.IV); and a guide part (20-20′″) which at least in portions receives the expander spring (10, 10′) in the longitudinal orientation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The invention will be described in more detail hereunder by way of various exemplary embodiments with reference to the appended figures, in which:

[0046] FIG. 1 shows a first embodiment of a disc brake according to the present disclosure;

[0047] FIG. 2 shows a sectional illustration of the disc brake of FIG. 1;

[0048] FIG. 3 shows a perspective exploded illustration of an embodiment according to the invention of a retainer bracket, an expander spring, and a guide part according to FIGS. 1 and 2;

[0049] FIG. 4 shows a perspective view of a further embodiment of a disc brake according to the present disclosure;

[0050] FIG. 5 shows a sectional illustration of the disc brake of FIG. 4;

[0051] FIG. 6 shows a perspective exploded illustration of a retainer bracket having a guide part configured thereon and an expander spring according to FIGS. 4 and 5;

[0052] FIG. 7 shows a perspective view of a further embodiment of a disc brake according to the present disclosure;

[0053] FIG. 8 shows a sectional illustration of the disc brake of FIG. 7;

[0054] FIG. 9 shows a perspective exploded illustration of a retainer bracket according to the invention, having an expander spring to be inserted therein, and a mating part;

[0055] FIGS. 10 and 11 show views of a further embodiment of a retainer bracket according to the invention, having a guide part configured thereon, and an expander spring to be assembled, as a sectional illustration;

[0056] FIGS. 12 and 13 show views of a further embodiment of a retainer bracket according to the invention, having an expander spring assembled on the guide part, and slides, in a perspective view and a sectional illustration;

[0057] FIG. 14 shows a perspective view of a further embodiment according to the present disclosure of a disc brake;

[0058] FIG. 15 shows a sectional illustration of the disc brake of FIG. 14;

[0059] FIG. 16 shows a perspective exploded illustration of a further exemplary embodiment of a retainer bracket having a guide part configured thereon, an expander spring, and a cover that is able to be assembled on the retainer bracket; and

[0060] FIG. 17 shows a perspective exploded illustration of the retainer bracket and of the expander spring of FIG. 16, having a protective cap which as an alternative to the cover is to be assembled on the retainer bracket and covers the upper side of the brake caliper.

DETAILED DESCRIPTION

[0061] FIG. 1 shows a disc brake 1 for a commercial vehicle, having a brake disc 2 and a brake caliper 3. One pair of brake pads 4, 4′ on the brake caliper 3 are movably guided on both sides of the brake disc 2, said brake pads 4, 4′ upon activation of the brake applying a brake force on brake faces of the brake disc 2. While the brake is being activated, the brake pads 4, 4′ are converged.

[0062] The disc brake 1 furthermore comprises retainer springs 6, 6′, wherein one retainer spring 6, 6′ is in each case disposed on one brake pad 4, 4′. The disc brake 1 moreover comprises a retainer bracket 8 which is specified for pre-tensioning the retainer springs 6, 6′ in relation to the respectively assigned brake pad 4, 4′, in particular in the radial direction R (FIG. 2) in terms of a rotation axis, not illustrated in more detail, of the brake disc 2.

[0063] Furthermore provided on the disc brake 1, in particular the retainer bracket 8, is an expander spring 10 which is specified for applying an expansion force between the brake pads 4, 4′ and diverging the brake pads upon activation of the brakes. The expander spring 10 preferably acts in such a manner that the contact between the brake faces of the brake disc 2 and the brake pads 4, 4′ is cancelled.

[0064] The retainer bracket 8 in the present embodiment at one end is held in a plug-in receptacle S and at the opposite end is secured on the brake caliper 3 by a fastening screw 12.

[0065] As is apparent from FIG. 2, the expander spring 10 has two ends 14, 14′ which bear in each case directly on one of the retainer springs 6, 6′ and transmit the expansion force generated by the spring body 16 of the expander spring 10 to the retainer springs 6, 6′ without the intervention of any potential coupling means.

[0066] For transmitting the expansion force generated by the spring body 16 of the expander spring 10, the expander spring on each end 14, 14′ thereof has a holding portion 18, 18′, wherein the holding portions 18, 18′ in each case contact an assigned retainer spring 6, 6′. In the embodiment shown, each holding portion 18, 18′ is integrally molded on an end portion of the expander spring 10. Moreover, the embodiment shown engages laterally across the retainer spring 6, 6′ at least in portions on the upper and the lower side of the latter.

[0067] The disc brake 1 furthermore has a guide part 20 by way of which the expander spring 10 at least in portions is guided in the effective direction of the expansion force. In the embodiment shown, the holding portions 18, 18′ are disposed outside the center of mass of the expander spring 10. The expansion force generated by the spring body 16 thus acts eccentrically on the retainer springs 6, 6′ so that the expander spring in the longitudinal orientation thereof is held transversely to the effective direction of the expansion force by way of the guide part 20.

[0068] FIG. 3 shows a perspective exploded illustration of the retainer bracket 8, the expander spring 10 and a guide part 20. All three components are configured separately from one another and in the present embodiment represent individual components of the disc brake 1 according to the present disclosure.

[0069] The expander spring 10 in the embodiment shown is configured as a coil spring. The guide part 20 is a bar element which is at least partially surrounded, in particular wrapped, by the expander spring 10. The guide part 20 and the expander spring 10 are received so as to be movable in a clearance 22 of the retainer bracket 8. The guide part 20 by way of the longitudinal axis thereof is disposed so as to be offset from the retainer bracket 8. The opposite ends 23, 23′ of the clearance 22, the latter having a rectangular basic shape, form in each case one detent for the movement of the guide part 20.

[0070] FIG. 4 shows a further embodiment according to the invention of a disc brake 1. In terms of the fundamental design embodiment and functional mode of this exemplary embodiment reference is made to the explanations pertaining to the embodiment of a disc brake according to the present disclosure shown in FIG. 1.

[0071] The expander spring 10 shown in this embodiment also bears directly on the retainer springs 6, 6′ of the disc brake 1. The disc brake 1 comprises a retainer bracket 8′ on which is provided a guide part 20′ which, as opposed to the first embodiment, is configured so as to be integral to the retainer bracket 8′. Provided on the retainer bracket 8′ is a clearance 22′, the guide part being disposed within the latter so as to extend parallel to the longitudinal direction of the clearance 22′.

[0072] In one embodiment, the guide part 20′ has a first guide mandrel 24 and a second guide mandrel 26 which extend toward one another from opposite ends 23, 23′ of the clearance 22′. The expander spring 10 is received by the first guide mandrel 24 and the second guide mandrel 26. The first and the second guide mandrel 24, 26 extend along a portion within the expander spring 10. Besides a guide, a loss prevention device for the expander spring 10 is present by way of the guide part 20′ which is configured so as to be integral to the retainer bracket 8′. In this way, the expander spring 10 is permanently held on the brake 1 even in the absence of the expansion force.

[0073] As is apparent from FIGS. 5 and 6, the first guide mandrel 24 and the second guide mandrel 26 terminate at a predefined mutual spacing X and define an introduction gap 28 for the expander spring 10. The introduction gap 28 makes it possible for the expander spring by way of one end to be pushed over the first guide mandrel 24, and the opposite end of the expander spring 10 to then be pushed onto the second guide mandrel 26. Moreover, the longitudinal axes of the guide mandrels 24, 26 have an offset from the plane of the retainer bracket 8′.

[0074] As is furthermore apparent from FIGS. 5 and 6, the first and the second guide mandrel 24, 26 are of dissimilar lengths. In this way, the introduction gap 28 is disposed so as to be offset from the ends 23, 23′ of the clearance 22′. The expander spring 10, as a result of the eccentric engagement of the holding portions 18, 18′ thereof, is again eccentrically stressed. The kinking of the expander spring 10 is presently counteracted by the first and the second guide mandrel 24, 26 of the guide part 20.

[0075] FIG. 6 highlights that the expander spring 10 has a normal length L.sub.N at which the expander spring 10 is not compressed. The expander spring 10 furthermore has a block length L.sub.B which corresponds to the length of the expander spring 10 in the maximum compressed state of the latter. The spacing X between the ends of the first and the second guide mandrel 24, 26 is smaller than the block length L.sub.B of the expander spring 10 so that the latter, even when compressed to the maximum, cannot move out of the introduction gap 28.

[0076] FIG. 7 shows a further embodiment of a disc brake 1 according to the invention, reference in terms of the fundamental design embodiment and function thereof being made to the explanations pertaining to FIG. 1. Disposed on the brake caliper 3 is again a retainer bracket 8″ again having a guide part 20″ configured so as to be integral to the retainer bracket 8″. The guide part 20′ in the clearance 22′ has a first guide mandrel 24′ and a second guide mandrel 26′.

[0077] As is highlighted by FIGS. 8 and 9, the first guide mandrel 24′ and the second guide mandrel 26′ are of identical lengths, wherein a mating part 30, which fills an introduction gap 28′ present between the ends of the guide mandrels 24′, 26′, is inserted between the free ends of the first and the second guide mandrel 24′, 26′.

[0078] An expander spring 10′, the ends 14, 14′ thereof, as opposed to the previously described embodiment, engaging on the retainer springs without holding portions configured on the spring body 16′, is received on the retainer bracket and the guide part 20″ of the latter. As opposed to the previous embodiment, the guide part 20″ by way of the guide mandrels 24′, 26′ thereof, runs in the clearance 22′ so as to be in one plane with the retainer bracket 8″. A loss prevention device for the expander spring 10′ on the disc brake according to the invention is also implemented by way of the guide part 20″ which is configured so as to be integral to the retainer bracket 8″.

[0079] The mating part 30 which is disposed between the ends and fills the introduction gap 28′ is preferably produced from a bent sheet-metal part which at the ends thereof has in each case mountings 32 for fastening to the first and the second guide mandrel 24′, 26′. Kinking of the eccentrically compressed expander spring 10′ is more intensely counteracted by way of the mating part 30.

[0080] FIGS. 10 and 11 show a further embodiment of a retainer bracket 8′″ according to the invention. The retainer bracket 8′″ has a guide part 20′″ which runs in a clearance 22′ and is configured from at least one first guide mandrel 24″ and one second guide mandrel 26″. As opposed to the previous design embodiments, the guide mandrels 24″, 26″ terminate at a minor mutual spacing, the latter defining a slot 33 of a few millimeters.

[0081] In order to be able to assemble an expander spring 10′ on the retainer bracket according to the invention, at least one of the guide mandrels 24″, 26″, presently the first guide mandrel 24″, is able to be moved in a reciprocating manner between an operating position, shown in FIG. 11, and an assembly position for assembling the expander spring, shown in FIG. 10. To this end, at least one portion of the first guide mandrel 24″ is configured so as to be able to be plastically or elastically deformed. For assembling the expander spring 10, the first guide mandrel 24″ is moved out of the plane of the retainer bracket 8′″ by a disengagement force which acts transversely to the longitudinal extent of the guide mandrel 24″. After pushing on the end 14 of the expander spring 10′ and compressing the expander spring 10′, the first guide mandrel 24″ is moved back into the plane of the retainer bracket 8′″ and the other end 14 is moved over the second guide mandrel 26″.

[0082] A further embodiment of a disc brake 1 according to the invention, which relates to a refinement of the embodiment of the retainer bracket 8′″ shown in FIGS. 10 and 11, is shown in FIG. 12. In terms of the fundamental design embodiment and function of this embodiment, reference is made to the explanations above pertaining to FIG. 1.

[0083] Instead of an expander spring 10′ that bears directly on a respective retainer spring 6, 6′, the ends 14, 14′ of the expander spring 10′ are in each case assigned one slide 40, 40′. The slides 40, 40′, which in the present embodiment are configured as a type of sleeve member and are guided along the guide part 20′″, serve as a connecting means between the expander spring 10′ and the retainer springs 6, 6′ on the brake pads 4, 4′. An evenly distributed effect of force across the circumference of the expander spring 10′ configured as a coil spring is achieved by way of the slides 40, 40′. The ends 14, 14′ of the expander spring 10′ bear in a fully circumferential manner on an end side 42 of the slide 40 (FIG. 13). The opposite end side 42′ bears on the respective retainer spring 6, 6′.

[0084] As is furthermore apparent from FIG. 13, each slide 40, 40′ has a minimum length which counteracts any jamming or canting by virtue of friction along the guide part 20″. The design embodiment shown in FIG. 13 also has a first guide mandrel 24″ and a second guide mandrel 26″ of dissimilar lengths. At least the first guide mandrel 24″ is configured so as to be able to be plastically or elastically deformed. The first guide mandrel 24″ and the second guide mandrel 26″ terminate at a minor mutual spacing X.sub.1, wherein the slot 33 formed by the spacing is positioned below the slide 40′, as is shown in FIG. 13. In the operating position of the first guide mandrel 24′, the slide 40′ secures the guide mandrel 24″ in relation to a movement out of the axis of the guide part 20″.

[0085] The slot 33 between the guide mandrels 24″ and 26″ is disposed on that side of the retainer bracket 8′″ that is assigned to the retainer spring 6′ and thus to the brake pad 4′ which is immovable relative to the brake caliper 3. The guide part 20′″ in the present embodiment has a rectangular cross section.

[0086] As a result of the guide mandrels that terminate at a minor mutual spacing X.sub.1 and of the slide 40′ that covers the slot 33 between the guide mandrels 24″, 26″, a design embodiment of a loss prevention device is implemented.

[0087] FIG. 14 shows a further embodiment of a disc brake 1 according to the invention. In terms of the specific design embodiment and functional mode reference is again made to the explanations pertaining to the embodiment shown in FIG. 1.

[0088] As is apparent from FIGS. 14 to 16, the disc brake 1 has a retainer bracket 8.sup.IV on which a cover 34 for the expander spring is additionally provided, the expander spring 10′ received on the retainer bracket 8.sup.IV being at least in portions covered by way of said cover 34. The expander spring 10 by way of the ends thereof engages directly on one of the retainer springs 6, 6′. The guide part 20′ that guides the expander spring 10′ again has a first guide mandrel 24 and a second guide mandrel 26 which again run in a plane with the retainer bracket 8.sup.IV and extend toward one another from opposite ends 23, 23′ of the clearance 22′.

[0089] The first and the second guide mandrel 24, 26 are of dissimilar lengths and terminate at a predefined mutual spacing, as a result of which an introduction gap 28 for the expander spring 10′ is present. In a manner similar to the mating part 30 to be positioned between the ends of the guide mandrels, it is achieved with the aid of the cover 34 that the expander spring 10′, despite an expansion force being transmitted eccentrically by the latter, does not kink transversely to the longitudinal direction of said expander spring 10′. The cover 34 is fastened to the retainer bracket 8.sup.IV by way of corresponding fastening means 36.

[0090] In an embodiment shown in FIG. 17, the cover 34 is part of a protective cap 36 for the brake caliper 3, wherein the protective cap 36 almost completely covers the upper side of the brake caliper 3. In a manner similar to the cover 34, the protective cap 38 is secured by way of two fastening means 36 that are able to be fastened to the retainer bracket 8.sup.IV.

[0091] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varies in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of disclosure.

LIST OF REFERENCE SIGNS (COMPONENT PART OF THE DESCRIPTION)

[0092] 1 Disc brake [0093] 2 Brake disc [0094] 3 Brake caliper [0095] 4, 4′ Brake pads [0096] 6, 6′ Retainer spring [0097] 8-8.sup.IV Retainer bracket [0098] 10, 10′ Expander spring [0099] 12 Fastening screw [0100] 14, 14′ End [0101] 16, 16′ Spring body [0102] 18, 18′ Holding portion [0103] 20-20′″ Guide part [0104] 22, 22′ Clearance [0105] 23, 23′ End of clearance [0106] 24, 24′, 24″ First guide mandrel [0107] 26, 26′, 26″ Second guide mandrel [0108] 28, 28′ Introduction gap [0109] 30 Mating part [0110] 32 Mounting [0111] 33 Slot [0112] 34 Cover [0113] 36 Fastening means [0114] 38 Protective cap [0115] 40, 40′ Slide [0116] 42, 42′ End side [0117] L.sub.B Block length of the spring [0118] L.sub.N Normal length of the spring [0119] R Radial direction [0120] S Plug-in receptacle [0121] X, X.sub.1 Spacing