DISC BRAKE AS WELL AS LEAF SPRING AND ATTACHMENT BRACKET ON A HOLDER ARRANGEMENT FOR THE BRAKE PADS OF A DISC BRAKE

Abstract

The invention relates to a disc brake comprising a brake calliper (1) engaging over a brake disc (2) and brake pads (3) on both sides of the brake disc, a hold-down means (10) for the pads securing the brake pads (3) against falling out of the disc brake, which extends, in contact with the rear plates (5) of both brake pads (3), in the transverse direction in relation to same, and comprising a flat spring (12) which is spring-elastically in contact with the side of the hold-down means (10) for the pads facing away from the brake pads (3), which extends in the longitudinal direction thereof, and which is supported with both spring ends (31, 32) thereof in spring abutments (21, 22). A securing means (8) is a component of one of the spring abutments, which extends transverse to the hold-down means (10) for the pads and to the flat spring (12). In order to improve and simplify the assembly of the hold-down assembly by technical means, e.g. after exchanging the brake pads, according to the invention, a further component of the hold-down means (21) of the spring is a clip (40) which is connected to the brake calliper (1) via the securing means (8), and with which the inner side (45) of the spring end (31) facing the securing means (8) is in contact.

Description

'Disc brake, as well as leaf spring of a hold-down arrangement for the brake pads of a disc brake' The invention relates to a disc brake with a brake caliper that overlaps a brake disc and brake pads on both sides of the brake disc, a pad retainer that secures the brake pads against falling out of the disc brake, which extends transversely to the backing plates of both brake pads, and with a leaf spring that elastically rests against the side of the pad retainer facing away from the brake pads, extends in its longitudinal direction, and is supported with its two spring ends in spring abutments, wherein a fastening means extending transversely to the pad retainer and the leaf spring is a component of one of the spring abutments.The invention further relates to a leaf spring of a brake pad retainer assembly for a disc brake, with a contact point arranged on a central section of the leaf spring in the form of a bend or curvature of the leaf spring with the curvature facing the brake pads. The invention further relates to a bracket and, in particular, a mounting bracket for a brake pad retainer assembly comprising a pad retainer and a leaf spring. For disc brakes with a caliper that holds the brake pads in pad recesses, measures are required to secure the brake pads against falling out of the recesses. For this purpose, the pad recess is often bridged by a sturdy retaining bracket, which extends transversely to the brake pads and is attached to the caliper at its ends, as is done, for example, in EP 1 069 334 B1, EP 2 057 384 B1, DE 10 2005 044 091 A1, DE 10 2005 045 877 B3, DE 20 2008 013 446 111 or DE 10 2015 000 857 A1. A leaf spring is arranged between the retaining bracket and each brake pad. Its ends rest against the backing plate of the respective brake pad, and its midpoint is supported from below by the retaining bracket. This creates a constant downward force on the brake pads, directed towards the axis of rotation of the brake disc.Since, in the aforementioned disc brakes, the springs supported by the brake pads are exposed to the heat of the brake pads and the brake disc, technical solutions are known from EP 2 687 746 B1 and EP 1 898 115 B1 in which no spring elements are located between the retaining bracket extending transversely across the pad recess and the brake pads. Instead, a single leaf spring is arranged on the outside of the rigid retaining bracket and exerts a spring force on it directed towards the brake pads. The retaining bracket itself thus acts as the pad retainer, bearing directly against the upper edge of the backing plates of the brake pads. The leaf spring is supported at its midpoint against the upper surface of the pad retainer facing away from the brake pads, while its two ends are fixed in spring abutments on the brake caliper.One component of the spring abutment is a fastening element in the form of a bolt, which extends transversely to the brake pad retainer and the leaf spring. The bolt serves to lock both the brake pad retainer and the leaf spring. This dual locking function, achieved by inserting the bolt, leads to disadvantages during the assembly of the retainer assembly, for example, after replacing the brake pads due to wear. The invention is based on the task of improving and simplifying the assembly of the hold-down arrangement, e.g. after replacing the brake pads, through technical measures. To solve this problem in a disc brake of the type mentioned above, it is proposed that a further component of the spring support be a bracket which is connected to the brake caliper by the fastening means, and against whose inner side facing the fastening means the spring end rests. Although the bracket represents an additional component within the retainer assembly, it improves and simplifies the assembly of the functional unit consisting of the pad retainer and leaf spring, particularly with regard to the unfavorable preload under which the leaf spring is already positioned during assembly. With this invention, the fastening element, preferably a bolt, can be inserted relatively easily and safely onto the brake caliper despite the preload of the leaf spring, thereby simultaneously positioning the pad retainer and the leaf spring in their intended positions. The design of the leaf spring also contributes to solving the aforementioned problem if it is provided at one end with a positive locking element that extends substantially transversely to the main extent of the leaf spring. This positive locking element secures the leaf spring in the position of the spring abutment, which includes the bolt. Preferably, the leaf spring is provided with a bend at the end, the outer surface of which is located on the same main surface of the leaf spring as the outer surface of the curvature at the contact point. Preferably, the leaf spring is also provided at its other end with a positive locking element extending substantially transversely to the main extent of the leaf spring, wherein the two positive locking elements extend in opposite directions with respect to the two main sides of the leaf spring. The positive locking element at the other end of the leaf spring allows the leaf spring to engage behind the pad retainer. This results in a longitudinal coupling between this other end of the spring and the pad retainer. To form the second positive locking element, the leaf spring can be provided with a reduced taper compared to the rest of the leaf spring's width. In a further embodiment, it is proposed that the leaf spring bears elastically against the pad retainer only at a single point along its length, with the leaf spring exhibiting a curvature at this point, e.g., in the form of a kink, and bearing against the pad retainer with its outer surface of the curvature.According to a further embodiment, the brake pad retainer has two longitudinal sections in the area of ​​the spring abutment, separated from each other by an open central section. The inner sides of these sections face each other and a bearing block that is integrally formed with the brake caliper and to which the fastening element is detachably attached. In this case, it is advantageous if the bracket is supported against the opposing outer sides of the longitudinal sections in the longitudinal direction of the bolt. The design of the bracket or mounting bracket for use in the disc brake also contributes to solving the aforementioned problem. This bracket is integrally composed of a central section and side sections angled relative to the central section, the side sections having mutually aligned openings for the passage of the fastening element, preferably designed as a bolt. Preferably, the central section has an opening in the form of a slot extending towards the side sections. An exemplary embodiment of a disc brake with a hold-down arrangement is explained in more detail below with reference to the drawings. These show: Fig. 1 shows a perspective top view of the central part of the brake caliper of a Vehicle disc brake including the pad recess formed in the brake caliper, in which brake pads are arranged on both sides of the brake disc; Fig. 2 shows the objects from Fig. 1 in a different perspective top view; Fig. 3 shows a cross-section through a hold-down arrangement consisting of a Brake pad retainer, a leaf spring, a bracket and a bolt attached to the brake caliper; Fig. 4 shows a perspective view of the bracket; Fig. 5a shows a side view of the pad retainer only; Fig. 5b shows a top view of the coating retainer. Fig. 1 shows the central part of the brake caliper 1 of a vehicle disc brake for commercial vehicles. The disc brake can be of the sliding caliper type or the fixed caliper type. A brake pad 3 is arranged on each side of the brake disc 2. To accommodate the brake pads 3, the brake caliper 1 is provided with a pad recess 6, over which a pad retainer 10 extends. The pad retainer 10 bridges the pad recess 6 in such a way that it extends transversely to the brake pads 6. The brake pads 3 consist, as usual, of the actual friction lining 4 and a lining backing plate 5, which guides and supports the brake pads 3 on the brake caliper or on an axle-mounted brake carrier. The elongated pad retainer 10 extends parallel to the axis of rotation of the brake disc 2. Its two ends can be attached directly or indirectly to the brake caliper 1. For this purpose, one end of the pad retainer 10 projects under a recess 7 of the brake caliper 1 and is thus directly attached to the brake caliper 1. The other end of the pad retainer 10 is detachably attached to the brake caliper 1 by means of a fastening element 8, in this case a cylindrical bolt. To secure the two brake linings 3 in the lining 6, the lining retainer 10 is designed as a substantially rigid retaining bracket and combined with a flexible leaf spring 12 to form a retainer assembly. The rigid lining retainer 10 has a cross-section with an underside facing the brake linings 3, to which chamfers 15 extend towards both longitudinal edges, giving the lining retainer 10 an overall trapezoidal cross-section in the area of ​​its underside. The lining retainer 10 rests solely on the chamfers 15 against correspondingly chamfered contours with which the lining backing plates 5 are provided at their upper edges. In this way, the pad retainer 10 secures the brake pads 3 in the pad recess 6, preventing the brake pads 3 from protruding or falling out of the pad recess 6 radially outwards, relative to the axis of rotation of the brake disc. The angled arrangement of the contact surfaces also provides a degree of lateral stability to the two brake pads. The brake pad retainer 10 also has a cross-section similar to a trapezoidal groove on the side facing away from the brake pads 3. This groove has a flat bottom, which is approximately the width B of the leaf spring 12, and slopes on both sides. The leaf spring 12, made of spring steel, is fastened with one end 31 in a first spring support 21 and with its other end 32 in a second spring support 22, each fastening being releasable in order to remove the leaf spring 12 and the pad retainer 10 arranged below it, and thus to access the pad shaft 6 for the replacement of the brake pads. The leaf spring extends longitudinally and parallel to the brake pad retainer 10 on the outside and is supported against it, thus subjecting the brake pad retainer 10 to spring force towards the brake pads 3. In this way, the brake pad retainer, although rigid itself, bears under constant spring force directly against the outer edge of the backing plate 5 of the two brake pads 3. The leaf spring 12 is not supported along its entire length, but only at a very short contact point 35 on the brake pad retainer 10. To achieve this contact point 35, which is located on a central section of the leaf spring 12, the leaf spring is provided with a bend or curve 30. The curve is a bend comparable to a kink around a bending line that extends transversely to the longitudinal extent of the leaf spring. With the outer side of this bend or curve 30, the leaf spring 12 rests directly against the bottom of the channel of the coating retainer 10. Only at the location of this discrete attachment or curve 30Therefore, the pad retainer 10 is subjected to spring force in the direction of the brake pads 3 for support. In the embodiment described here, the first spring abutment 21 is located on the outside of the vehicle, and the second spring abutment 22 is located on the inside of the vehicle at the brake caliper 1. Only the first spring abutment 21 is provided with the bolt 8 for locking the pad retainer 10 and the leaf spring 12. In contrast, the brake caliper 1 is provided with an opening or recess 24, open towards the pad recess 6, to form the second spring abutment 22. This opening or recess provides space for both the end of the pad retainer 10 and the end of the spring 32. For the assembly of the pad retainer and leaf spring, it is advantageous that the ends of these two components, which are inserted together into the opening or recess 24 of the brake caliper, are locked to each other longitudinally.For this purpose, the brake pad retainer 10 is provided at this end 20 with an end face 23, behind which a positive locking element 39 formed at the corresponding spring end 32 of the leaf spring engages (Fig. 2). For this engagement, the leaf spring 12 is essentially angled transversely at the spring end 32, with this angle engaging behind the end face 23 of the brake pad retainer 10 within the opening or recess 24. The locking achieved in this way has the effect that, as soon as the brake pad retainer 10 is located in the opening or recess 24 of the brake caliper, the leaf spring 12 is locked longitudinally, i.e., captured by the brake pad retainer 10. This measure facilitates the subsequent fixing of the brake pad retainer 10 and, above all, the leaf spring 12 at the other end, i.e., in the area of ​​the first spring abutment 21. In the area of ​​the first spring abutment 21, the pad retainer 10 is cranked, as can be seen in Fig. 5a, by having a bend at this end. When the bolt 8 is installed, this bend engages under the bolt 8, so that this end of the pad retainer is caught by the bolt and cannot detach outwards from the brake caliper 1 even if the leaf spring 12 is missing or fails. Furthermore, a longitudinal locking mechanism for the brake pad retainer 10 is achieved by its curved end section being composed of two longitudinal sections 55A, 55B separated by an open central area 54. The transverse rim 57 connecting the two longitudinal sections 55A, 55B, in the assembled state, faces a bearing block 25, which is integrally formed with the brake caliper 1 and primarily serves to accommodate the bolt 8 and thus the fastening element. The longitudinal movement of the brake pad retainer 10 is therefore limited in both directions: firstly, by the transverse rim 57 abutting the bearing block 25, and secondly, by the other end of the brake pad retainer 10 abutting the opening or recess 24 of the brake caliper. The bearing block 25, integrally formed with the brake caliper 1, has a bore for the passage of the bolt 8.The longitudinal sections 55A, 55B of the brake pad retainer 10, with their mutually facing inner surfaces 56A, 56B, face the bearing block 25 in the longitudinal direction of the bolts, with the inner surface 56A of one longitudinal section 55A facing the bearing block 25 from one side, and the inner surface 56B of the other longitudinal section 55B facing the bearing block 25 from the other side. However, a certain degree of mobility of the brake pad retainer 10 relative to the bearing block in the circumferential direction, i.e., in the direction of rotation of the brake disc, is important. As shown in Fig. 3, the curved longitudinal sections 55A, 55B of the pad retainer 10, when assembled, have a certain distance from the cylindrical bolt 8. Their undersides, facing away from the bolt 8, also have a distance from the opposite surface 27 of the brake caliper 1. This is because the pad retainer 10, precisely because of its retaining function, is primarily supported by the two brake pads 3. Fig. 3 also shows the locking mechanism of the spring end 31 on the spring support 21. Besides the bolt 8, this spring support 21 includes a mounting bracket 40, which is connected to the bearing block 25 of the brake caliper by the bolt 8. The leaf spring 12 rests with its spring end 31 against the inner surface 45 of the bracket 40, which faces the bolt 8. As an additional safety measure, a positive locking element 36, formed at the very end of the spring end 31, engages in a slot-shaped opening 47 in the bracket 40. As shown in Fig. 4, the bracket 40 consists of a central section 41, against whose inner side the spring end 31 rests, and two side sections 42, 43 arranged approximately at right angles to the central section 41. The side sections 42, 43 of the bracket 40 each contain a round opening 46 through which the bolt 8 passes with minimal play near its ends. Preferably, the distance between the two side sections 42, 43 is such that one side section 42 can bear against the first curved longitudinal section 55A, and the other side section 43 against the second curved longitudinal section 55B of the lining retainer 10, in the longitudinal direction of the bolt. The bolt 8 serves as a fastening means to detachably attach the bracket 40 to the bearing block 25. At the same time, the leaf spring 12 is supported under spring tension on the inner side 45 of the central section 41 of the bracket 40 facing the bolt 8.The sum of these measures leads to securing and maintaining the bending stress of the leaf spring 12. The positive engagement of the angled positive locking element 36 formed at the spring end 31 into the opening 47 of the bracket 40, which is located in the central section 41, represents an additional securing measure. The leaf spring 12 is bent in a bowl-like shape at the spring end 31, with the outside of this bend 37 facing the bolt 8 when mounted. The outermost end of the spring end 31 can also be designed as a taper, which, in the assembled state, forms the positive locking element for engaging in the opening 47 of the bracket 40. In this case, the leaf spring is significantly narrower in the area of ​​the taper than in the area of ​​the remaining leaf spring width. The assembly of the pad retainer 10, leaf spring 12, bracket 40, and bolt 8 is carried out by first placing the leaf spring 12 onto the pad retainer 10 so that its angled end, forming a positive locking element 39, engages behind the end of the pad retainer 10. The parts thus provisionally connected are then pushed longitudinally into the opening or recess 24 of the brake caliper. In a next step, the bracket 40 is placed onto the spring end 31. This is simplified and, above all, made safer for the installer by the engagement of the angled end, which serves as a positive locking element 36, in the opening 47 of the bracket 40. The bracket 40 is then pressed down by manual pressure on its central section 41, bending the leaf spring, until the openings 46 in the side sections 42, 43 align with the bore of the brake caliper-mounted bearing block 25. Once this is the case, the bolt 8 is inserted longitudinally.The pressure exerted on the bracket 40 can then be stopped, since the tension force of the leaf spring 12 is now safely absorbed by the bracket 40 in conjunction with the bolt 8. To prevent the Bolz 8 from loosening again in the longitudinal direction of the bolt, suitable retaining rings, cotter pins or the like are provided on the bolt 8. Reference symbol list 1 brake caliper 2 brake discs 3 brake pads 4 friction lining 5 Backing plate 6 Cover shaft 7 Exclusion 8 bolts, fasteners 10 coating retainers 12 leaf spring 15 sloping 20 End 21 Spring stop 22 Spring abutments 23 Front surface 24 Opening, recess 25 bearing block 27 Area on the brake caliper 30 Curvature, bending 31 Spring end 32 Spring end 36 Positive locking element 37 bend 39 Positive locking element 40 brackets, mounting brackets 41 Middle section Section 42 Section 43 45 Inside 46 Opening 47 Opening 54 open center area 55A Longitudinal section B Longitudinal section A Inside B Inside Transverse edge

Claims

Patent claims 1. Disc brake with a brake caliper (1) encompassing a brake disc (2) and brake pads (3) on both sides of the brake disc, a pad retainer (10) securing the brake pads (3) against falling out of the disc brake, which extends transversely to the pad backing plates (5) of both brake pads (3) and bearing against them, and with a leaf spring (12) which elastically bears against the side of the pad retainer (10) facing away from the brake pads (3), extends in its longitudinal direction, and is supported at its two spring ends (31, 32) in spring abutments (21, 22), wherein a fastening element (8) extending transversely to the pad retainer (10) and the leaf spring (12) is a component of one of the spring abutments, characterized in that a further component of the spring abutment (21) is a bracket (40) which is connected to the pad retainer (10) by the fastening element (8). brake caliper (1) is connected,and the spring end (31) rests against the inner side (45) of the fastening element (8).

2. Disc brake according to claim 1, characterized in that the leaf spring (12) is provided at the spring end (31) with a positive locking element (36) for engagement with the bracket (40).

3. Disc brake according to claim 2, characterized in that the positive locking element (36) extends substantially transversely to the main extent of the leaf spring (12).

4. Disc brake according to claim 2 or 3, characterized in that the leaf spring (12) is provided at the spring end (31) with a bend (37) the outer side of which is facing the fastening means (8).

5. Disc brake according to one of claims 1 to 4, characterized in that the leaf spring (12) is provided at its other spring end (32) with a positive locking element (39) with which the leaf spring (12) engages the pad retainer (10) in the longitudinal direction.

6. Disc brake according to one of the preceding claims, characterized in that the leaf spring (12) bears against the pad retainer (10) only at a single point along its longitudinal extent in a spring-elastic manner, wherein the leaf spring (12) has a curvature (30) at this point and the outer side of the curvature bears against the pad retainer (10).

7. Disc brake according to one of the preceding claims, characterized in that the bracket (40) is integrally composed of a central section (41) against which the spring end (31) rests, and side sections (42, 43) angled relative to the central section (41), through which the fastening means (8) passes.

8. Disc brake according to claim 7, characterized in that the side sections (42, 43) each have an opening (46) through which the fastening means (8) passes.

9. Disc brake according to claim 7 or 8, characterized in that the central section (41) has an opening (47) into which a positive locking element (36) engages, with which the spring end (31) terminates.

10. Disc brake according to one of the preceding claims, characterized in that the pad retainer (10) in the area of ​​the spring abutment (21) has two sections separated from each other by an open central area (54). The disc brake (55A, 55B) has longitudinal sections (55A, 55B) whose inner sides (56A, 56B) face each other and a bearing block (25) which is integrally formed on the brake caliper (1) and to which the fastening means (8) is detachably attached. 1 1. Disc brake according to claim 10, characterized in that the bracket (40) is supported against the opposing outer sides of the longitudinal sections (55A, 55B).

12. Disc brake according to one of the preceding claims, characterized in that the fastening means (8) is a bolt.

13. Leaf spring (12) of a retaining arrangement for the brake linings of a disc brake, with a contact point (35) arranged on a central section of the leaf spring in the form of a bend or curvature of the leaf spring with the curvature facing the brake linings, characterized in that the leaf spring (12) is provided at one end (31) of its spring with a positive locking element (36) extending substantially transversely to the main extension of the leaf spring (12).

14. Leaf spring according to claim 13, characterized in that it is provided at the spring end (31) with a bend (37) whose outer side of the bend is on the same main side of the leaf spring (12) as the outer side of the curvature at the contact point (35).

15. Leaf spring according to claim 13 or 14, characterized in that it is also provided at its other spring end (32) with a positive locking element (39) extending substantially transversely to the main extension of the leaf spring (12), wherein the two positive locking elements (36, 39) extend in opposite directions with respect to the two main sides of the leaf spring (12).

16. Bracket (40), in particular a fastening bracket for a retainer assembly comprising a pad retainer and a leaf spring, which is integrally composed of a central section (41) and side sections (42, 43) angled relative to the central section (41), wherein the side sections (42, 43) have openings (46) aligned with each other for passing a fastening means through them.

17. Bracket (40) according to claim 16, characterized in that the central section (41) has an opening (47) in the form of a slot extending to the side sections. (42, 43) indicates.

18. Bracket (40) according to claim 16 or 17, characterized in that the side sections (42, 43) are arranged perpendicular to the central section (41).