DE102015100993A1 - Disc brake for a vehicle - Google Patents

Abstract

Proposed is a disc brake for a vehicle, with a brake disc (2) and on both sides of the brake disc (2) arranged brake pads (3, 4) cross-caliper with a caliper housing, in which an application device is arranged. Part of the application device is a pressure piece (10) which is rotatable about its longitudinal central axis (11) and against one of the brake pads can be applied. To protect the interior of the caliper housing against contamination, a bellows (24) is provided which is secured to a first end portion (31) on the caliper housing and a second end portion (32) on a plate (25) between the end face (12 ) of the pressing piece (10) and the brake pad (3) and is centered about centering with respect to the longitudinal central axis (11) of the pressure piece (10). In order to improve the sealing of the interior of the caliper housing, the pressure piece (10) is freely movable in the longitudinal direction relative to the plate (25), and the centering means consist of a first centering element which is formed as a cone (40) or truncated cone, and from a second centering element. The centering elements are on the one hand on the plate (25) and on the other hand on the end face (12) of the pressure piece (10) and / or a lining carrier plate (7) of the brake pad and / or a pressure plate (20), against which the brake pad (3) zuspannseitig is supported, arranged.

Description

The invention relates to a disc brake for a vehicle, with a brake disc and arranged on both sides of the brake disc brake pads cross caliper with a caliper housing, in which an application device is arranged, wherein component of the application device is a pressure piece, which is rotatable about its longitudinal central axis and against a the brake linings is zuspannbar, and wherein for protecting the interior of the caliper housing against contamination, a bellows is provided, which is secured to a first end portion of the caliper housing and a second end portion of a plate which is disposed between the end face of the pressure piece and the brake pad and centered about centering with respect to the longitudinal center axis of the pressure piece.

From the EP 1 646 801 B1 , of the EP 1 916 438 B1 and the DE 10 2005 034 868 B3 Disc brakes are known for use in commercial vehicles, with a brake disc and two brake pads cross-caliper, in the caliper housing an application device is arranged. Part of the application device is a pressure piece in the design of an adjusting spindle. To protect the interior of the caliper housing against contamination, a bellows is fixed with its first end to the caliper housing, and with its second end to a disposed between the end face of the pressure piece and the vehicle inner brake pad plate. The plate is connected in the longitudinal direction of the pressure piece. At the same time, it is centered on this with respect to the longitudinal center axis of the pressure piece. In addition, since the pressure piece rotates about its longitudinal central axis when the brake is adjusted, it is freely rotatable relative to the plate.

The aforementioned technical solutions have in common that the plate, since it is part of the sealing of the inner part of the caliper against contamination, participates in the longitudinal movements of the pressure piece during the tensioning and also during the release of the brake.

However, it has not proven to be really necessary that the plate closing the bellows outwardly follows all longitudinal movements of the pressure piece. However, it would not be readily possible in the known disc brakes to easily decouple the longitudinal movements of the plate on the one hand and the pressure piece on the other hand. Because a simple decoupling would also affect the centering between plate and pressure piece. However, sufficient centering is important to avoid damaging the bellows by chafing or crushing.

The aim of the invention are therefore improvements in the sealing of the interior of the caliper housing.

To solve this problem, a disc brake with the features of claim 1 is proposed.

• – an der Stirnseite des Druckstücks
• – und/oder an einer Belagträgerplatte des Bremsbelags
• – und/oder an einer Druckplatte, gegen die der Bremsbelag zuspannseitig abgestützt ist,

angeordnet.In such a disc brake, the pressure piece and the plate are decoupled from each other in the longitudinal direction. By means of two cooperating centering elements, the plate can be centered in a position on the longitudinal central axis of the pressure piece. The first of the two centering elements is a cone or truncated cone. The cooperating centering elements are on the one hand on the plate, and on the other

• - At the front of the pressure piece
• - And / or on a lining carrier plate of the brake pad
• - And / or on a pressure plate against which the brake pad is supported zuspannseitig,

arranged.

Due to the conical shape of the conical or frusto-conical centering element is able to release the pressure piece safely and under difficult conditions from the plate when releasing the brake. Conversely, when re-applying the brake, the conical conical shape or truncated cone shape leads to the fact that it already comes with the axial approach of the pressure piece to the plate to a first centering. Complete centering occurs as soon as the two components again come into complete axial contact and so the plate is taken through the pressure piece.

The decoupling of plate and thrust piece in the longitudinal direction is of particular importance when the pressure pad is part of an adjustment of the brake lining or brake disc wear adjusting device, and the pressure piece during adjustment performs a rotation about its own longitudinal central axis. However, such rotations should not be transmitted to the bellows via the plate, since even a slight twisting of the bellows negatively influences its deformation or compression behavior.

With a preferred embodiment, it is proposed that the height or axial length of the cone or truncated cone in the longitudinal direction is greater than the summed clearance of the brake between the brake pads and the brake disc. If these proportions are taken into account, there may be no situation in which the pressure piece in Loosening the longitudinal direction far enough from the plate that renewed centering is jeopardized when re-tightening.

In order to keep the production costs low in the production of the plate, the cones or truncated cones can be formed with the direction of taper towards the pressure piece.

To achieve a particularly durable and good seal, it is proposed that the second end region of the bellows be attached to the plate by vulcanization.

According to a further embodiment, the bellows is provided at its second end region with a circumferential annular groove, in which an annular edge zone of the plate sits, wherein the plate has a smaller thickness in the edge zone than within the edge zone. In addition, if the reduced thickness of the plate in the edge zone is achieved by a circumferential step, with which the plate is provided on its side facing away from the pressure piece, an excessive material stress on the mounting portion of the bellows can be avoided. Because in this case, during squeezing, there is no squeezing of the elastic material from which the bellows is made.

In order to keep the production costs low in the production of the plate, both the reduced thickness of the plate in the edge zone, as well as the formed on the plate cone or truncated cone can be the same forming process, for. B. the forming in a pressing and / or upsetting tool.

Further details and advantages will become apparent from the following description of the embodiments illustrated on the drawing. In detail show:

1 in a sectional view parts of a disc brake, wherein the cutting plane is placed on the Zuspannachse the disc brake, and wherein the situation is reproduced at clearly worn brake pads and brake is not applied;

2 individual objects 1 , but with new, not worn brake pad and fully retracted Zuspannung;

3 in the 1 designated item III in an enlarged view;

4 a second, compared to the 1 - 3 modified embodiment;

5 a third embodiment;

6 a fourth embodiment.

The 1 shows the parts of interest in the invention of a disc brake for a vehicle, and in particular a dedicated for a commercial vehicle, pneumatic disc brake. Components of the disc brake are not shown caliper, which can be designed as a fixed caliper or as a floating caliper, and a brake disc 2 , on both sides of brake pads 3 . 4 are arranged in the caliper. The brake pads 3 . 4 each consist of a friction lining 6 and a back plate carrier plate 7 ,

The brake caliper, not shown, consists of the brake disc in a conventional construction 2 U-shaped embracing caliper bridge and a caliper housing. In the caliper housing of the brake caliper is the brake application device. Under the application device those components of the disc brake are understood by means of which of a force member, for. As a compressed air cylinder, generated driving force in one of the brake pads 3 . 4 acting clamping force is transferred. In air-actuated disc brakes part of this application device is a pivotally mounted in the caliper housing, pressure-boosting brake lever.

Part of the disc brake is also an adjusting device. This serves to compensate for the increase in clearance due to the progressive wear on the brake pads and the brake disc clearance of the brake. With the adjustment of the brake it comes over time to a more and more displacement of a pressure piece 10 , which is part of the application device, to the brake disc 2 out.

Preferably, at least parts of the adjusting device are located within the pressure piece provided internally with a corresponding cavity 10 , The pressure piece 10 is designed essentially rotationally symmetrical. On its outside it is provided with an external thread and thus forms an screwed with an internal thread of a surrounding traverse spindle. When adjusting a slight twisting of this adjusting spindle takes place 10 around its longitudinal central axis 11 , where the adjusting spindle in the traverse slightly forward to the brake disc 2 screwed down, and so the clearance is corrected.

During braking, ie when the brake is applied, the pressure piece designed as an adjusting spindle is formed 10 to the brake pad 3 pressed against it, which in turn against the brake disc 2 is pressed. For a better pressure distribution can be between the pressure piece 10 and the lining carrier plate 7 of the brake pad 3 an additional pressure plate 20 are located. Due to its bending stiffness, this causes a more even pressure distribution over the front side 12 of the pressure piece 10 relatively concentrated initiated clamping force on the rather large pad backing plate 7 ,

Since the pressure piece 10 With increasing wear pad more and more moves out of the caliper housing, it requires one of these movement possibility fair protection of the interior of the caliper housing against external contamination. Because especially in the field of brake pads 3 . 4 There is a strong dust and moisture-laden atmosphere. For this reason, the caliper housing to the vehicle interior brake pad 3 and the brake disc 2 out with a seal 21 Mistake. This is essentially composed of a housing closure plate inserted into an opening of the brake caliper housing 23 , a deformable bellows 24 and one the bellows 24 outwardly closing and closing plate 25 ,

The bellows made of rubber or an elastomer 24 is with a first end area 31 against rotation on the housing sealing plate 23 and thus indirectly attached to the caliper housing. This attachment is preferably by means of a clamping ring 33 which is the first end area 31 against a surrounding opening of the housing closure plate 23 braced.

With its second end area 32 is the bellows 24 against rotation on the plate 25 attached. This attachment is preferably carried out by vulcanization. In particular, the bellows is in its second end region 32 with an integrally formed, circumferential annular groove 35 provided in the annular edge zone 25A the plate 25 sitting.

The plate 25 points in the annular edge zone 25A a smaller thickness than within the edge zone 25A , The connection between the annular edge zone 25A and the ring groove 35 takes place by vulcanization, since preferably the bellows 24 made of rubber, and the plate 25 Made of sheet steel. Embracing the plate 25 through the ring groove 35 is U-shaped, whereby the contact surface is relatively large. This offers a large and thus safe Vulkanisationsfläche.

The reduced thickness of the plate 25 in the border zone 25A relies on a revolving stage, with which the plate 25 on her the pressure piece 10 opposite outside 37 is provided. The inside 38 the plate 25 is, however, with the exception of a centrally located cone 40 , flat and even. The circumferential step provides space for the edge of the bellows attached there 24 so that it is at the tension, ie while supporting the outside of the plate 25 against the pressure plate 20 , no squeezing of sitting in the stage rubber material can come.

Alternatively, the plate 25 be formed on a more cup-shaped member, the edge is flanged to the outside.

The bellows 24 to the brake disc 2 towards completely closing plate 25 is between the front side 12 of the pressure piece 10 and the brake pad 3 or the against the brake pad 3 supported pressure plate 20 arranged.

The plate 25 is with respect to the longitudinal central axis 11 of the pressure piece 10 centered. As centering two cooperating centering serve. The first centering element is in alignment with the longitudinal central axis 11 of the pressure piece 10 arranged cones 40 at the plate 25 , The second centering element 50 is a correspondingly shaped cone on the front side 12 of the pressure piece 10 ( 3 ), which is also on the longitudinal central axis 11 is arranged. In the first embodiment according to the 1 - 3 So are both centering elements 40 . 50 each cone with direction of rejuvenation to the pressure piece 10 out.

Because the conical conical surfaces of the two cooperating cones 40 . 50 have substantially the same dimensions and both on the longitudinal central axis 11 are arranged, there is a play-free lateral centering of the pressure piece 10 relative to the plate 25 or the plate relative to the pressure piece. In the situation after 1 the pressure piece is supported 10 with his front side 12 from the inside flat against the inside 38 the plate 25 from. This in turn lies with its outside 37 flat on the pressure plate 20 at.

Does it come after a brake to the situation 1 , ie a release and thus a release of the brake, the pressure piece pulls 10 something back, with the pressure piece 10 in the longitudinal direction of the inside of the plate 25 can solve. Thus lose the corresponding conical surfaces 40 . 50 ( 3 ) their contact. However, the axial length or height H of the conical surfaces in the longitudinal direction is greater than the summed clearance L3 + L4 of the brake. In 1 is the clearance between the inner brake pad 3 and the brake disc 2 with L3, and the clearance between the outer brake pad 4 and the brake disc 2 denoted by L4. This is generally between 0.5 and 2 mm.

Due to the conical shape of the cone 40 . 50 can, when releasing the brake, the pressure piece 10 safe and under difficult conditions from the plate 25 to solve. Conversely, when applying the brake, the sufficient length of the cone shape that it already during the axial approach of the front side 12 to the inside of the plate 25 comes to a first, mutual centering. A complete centering occurs as soon as the two components 10 . 25 again come into complete axial contact and the plate 25 then through the pressure piece 10 is taken.

Although the conical surfaces therefore dissolve in the longitudinal direction of each other, but on the other hand only so far that they again come safely in centering contact with each other in the subsequent re-application of the brake. At the same time, the conical shape of the conical surfaces leads to a plate 25 and pressure piece 10 reliably solve each other without z. B. stiction effects hamper such a loosening.

In the first embodiment according to the 1 - 3 can both the reduced thickness of the plate 25 along the edge zone 25A , as well as on the plate 25 trained cones 40 Be results of the same forming process.

The 1 and 2 show in comparison that the bellows 24 as in axial compression in several layers layered bellows is formed, these layers are superimposed radially.

According to the second embodiment 4 the centering means consist of a truncated cone 41 at the plate 25 on the one hand and a corresponding truncated cone 51 at the front 12 of the pressure piece 10 on the other hand. Unlike the first embodiment, the truncated cones 41 . 51 with rejuvenation direction to the brake disc 2 trained. In addition, unlike the first embodiment, there is the pressure plate 20 unavailable. Rather, the plate which closes the bellows outwards is supported 25 with its outer side directly against the lining carrier plate 7 of the brake pad 3 from. The lining carrier plate 7 points, as another centering element for the plate 25 , a frusto-conical recess 54 on, in which the at the plate 25 trained truncated cone 41 additionally centered.

This recess 54 can also in that additional pressure plate 20 be present, which between the lining carrier plate 7 and the plate 25 can be arranged.

A centering of the plate 25 is also only opposite the lining carrier plate 7 or the printing plate 20 possible. Because not only the pressure piece 10 , but also the lining carrier plate 7 and the pressure plate 20 are position-centered within certain tolerances.

An advantage is a cone height H ( 3 ), which is an assembly of the second brake pad 3 . 4 prevents when the cone or truncated cone of the plate 25 not within the mating contour, so the centering element in the pressure piece 10 , dips. An incorrect installation of the plate 25 opposite the pressure piece 10 can thus be excluded during maintenance.

The third embodiment 5 shows that in the pressure piece 10 a blind hole instead of a cone 51 can be provided as centering. As a result, the mutual release of the pressure piece 10 and the plate 25 even safer. However, higher wear is to be expected because of the rather linear contact.

at 6 after all, that's the plate 25 trained centering a pin 53 , the largely free of play in a conical or frusto-conical depression 42 in the front side 12 of the pressure piece 10 protrudes, and so causes the centering.

LIST OF REFERENCE NUMBERS

2

 brake disc

3

 brake lining

4

 brake lining

6

 friction lining

7

 Backing plate

10

 Pressure piece, adjusting spindle

11

 Longitudinal central axis

12

 front

20

 printing plate

21

 seal

23

 Housing lock plate

24

 bellow

25

 plate

25A

 border zone

31

 first end area

32

 second end area

33

 clamping ring

35

 ring groove

37

 outside

38

 inside

40

 Centering element, cone

41

 Centering element, truncated cone

42

 Centering element, countersink

50

 Centering element, cone

51

 Centering element, truncated cone

52

 Centering element, blind hole

53

 Centering element, pin

54

 Centering element, recess

H

 height

L3

 Clearance inside

L4

 Clearance outside

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1646801 B1 [0002]
• EP 1916438 B1 [0002]
• DE 102005034868 B3 [0002]

Claims (11)

Disc brake for a vehicle, with a brake disc ( 2 ) and on both sides of the brake disc ( 2 ) arranged brake pads ( 3 . 4 ) comprehensive caliper with a caliper housing, in which an application device is arranged, wherein component of the application device is a pressure piece ( 10 ) which is about its longitudinal central axis ( 11 ) is rotatable and can be applied against one of the brake pads, and wherein for protecting the interior of the caliper housing against contamination a bellows ( 24 ) provided with a first end region ( 31 ) on the caliper housing and with a second end region ( 32 ) on a plate ( 25 ) is fixed between the front side ( 12 ) of the pressing piece ( 10 ) and the brake pad ( 3 ) and centering means with respect to the longitudinal central axis ( 11 ) of the pressure piece ( 10 ) is centered, characterized in that the pressure piece ( 10 ) in the longitudinal direction freely movable relative to the plate ( 25 ), and that the centering means consists of a first centering element, which is used as a cone ( 40 ) or truncated cone ( 41 . 42 ) is formed, and from a second centering element ( 50 . 51 . 52 . 53 . 54 ) and on the one hand on the plate ( 25 ) and on the other hand on the front side ( 12 ) of the pressure piece ( 10 ) and / or a lining carrier plate ( 7 ) of the brake pad and / or a pressure plate ( 20 ), against which the brake pad is supported zuspannseitig arranged. Disc brake according to claim 1, characterized in that the second centering element ( 50 . 51 . 54 ) is also a cone or a truncated cone. Disc brake according to claim 1, characterized in that the second centering element ( 52 ) is a blind hole into which the cone ( 40 ) or truncated cone ( 41 ). Disc brake according to Claim 1, characterized in that the second centering element engages in the cone ( 40 ) or truncated cone ( 41 ) extending pin ( 53 ). Disc brake according to one of the preceding claims, characterized in that the length of the cone ( 40 ) or truncated cone ( 41 . 42 ) is greater in the longitudinal direction, than the summed clearance (L3, L4) of the brake between the brake pads ( 3 . 4 ) and the brake disc ( 2 ). Disc brake according to one of the preceding claims, characterized in that the cone ( 40 ) or truncated cone ( 41 ) with tapering direction to the pressure piece ( 10 ) is formed out. Disc brake according to one of the preceding claims, characterized in that both centering elements ( 40 . 50 ) Are cones. Disc brake according to one of the preceding claims, characterized in that the second end region ( 32 ) of the bellows ( 24 ) by vulcanization on the plate ( 25 ) is attached. Disc brake according to one of the preceding claims, characterized in that the bellows ( 24 ) at its second end region ( 32 ) with a circumferential annular groove ( 35 ), in which an annular edge zone ( 25A ) of the plate ( 25 ) sits, and that the plate ( 25 ) in the marginal zone ( 25A ) a smaller thickness than within the edge zone ( 25A ) having. Disc brake according to claim 9, characterized in that the reduced thickness of the plate ( 25 ) in the marginal zone ( 25A ) is achieved by a circumferential step, with which the plate ( 25 ) on her the pressure piece ( 10 ) facing away from the side. Disc brake according to claim 9 or 10, characterized in that both the reduced thickness of the plate ( 25 ) in the marginal zone ( 25A ), as well as on the plate ( 25 ) trained cone ( 40 ) or truncated cone ( 41 ) Are results of the same forming process.

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