Disc brake for a commercial vehicle and brake pad for a disc brake

Abstract

Disc brake (1) for a commercial vehicle, comprising a brake caliper (2) designed as a sliding caliper and spanning a brake disc (9), two brake pads (3) arranged therein, movable in opposite directions in the direction of the brake disc (9), each having a pad carrier plate (5) and a friction pad (6) fastened thereon, each of which is arranged under pretension by means of a pad retaining spring (7), on which a pad retaining bracket spanning a mounting opening of the brake caliper (2) is supported, in a pad shaft of a vehicle-side brake carrier delimited by brake carrier horns (4) in the direction of rotation of the brake disc (9), and with return devices with which the brake pad (3) can be returned after a braking-induced displacement and release of the brake, characterized in thatthat at least one of the mutually facing and contacting regions of the lining carrier plate (5) and / or the lining retaining spring (7) is designed as a slope (11) sloping towards the friction lining (6).

Description

The invention relates to a disc brake for a commercial vehicle according to the preamble of claim 1 and to a brake pad for a disc brake.During braking by means of such a disc brake, the brake pads are tightened by a tightening device first by pressing the brake pad on the tightening side against the brake disc and a subsequent pressing of the opposite brake pad on the reaction side.The action-side brake pad is pressed against the brake disk by brake plungers of the application device, while, in order to press on the reaction-side brake pad, the brake caliper, which is designed as a sliding caliper, is displaced against the application device of the action-side brake pad.After releasing the brake, in the known disc brake the brake caliper remains in this latter position, in which the brake linings, but at least the reaction-side, bear on the brake disc without pressure, but in a sliding manner.The so-called residual grinding torques which thus occur during the driving operation lead to an increased fuel consumption of the vehicle and to a reduction in the service life of both the brake disc and the brake pads.While during driving, a slight release of the brake linings takes place as a result of a wobble stroke of the brake disk and also as a result of vibrations and transverse accelerations during cornering, these effects are not sufficient to effectively prevent the mentioned slipping.It is therefore proposed in WO 2016 / 202 778 A1 to provide a disc brake with spreading elements forming a restoring device, with which the brake pads of the disc brake are actively restored after a braking has ended, i.e. are brought out of the engagement region of a vehicle-side brake disc.These spreading elements have spring arms which engage in the mutually opposite brake linings, in particular in their lining carrier plates, and are held on a vehicle-side brake carrier. This construction prevents residual grinding torques from arising, which lead to increased wear of the brake linings.DE 43 01 621 A discloses a disc brake with a stationary brake carrier which has two lining shafts for receiving the brake linings, each lining shaft being bounded in both circumferential directions of the brake disc by brake carrier horns on which a lining carrier plate of the respective brake lining carrying a friction lining is supported in a sliding manner in the application direction.For resetting the brake pads, a spring arrangement is provided which acts on the brake pads axially in the brake release direction and assists an adjustment of the clearance between the brake shoes and the brake disc after the brake has been released.This spring arrangement has two expansion springs each having two spring arms which bear resiliently against the lining carrier plate above the friction lining, the respective expansion spring being fixed to a stationary component, for example to the brake carrier.In more recent designs of disc brakes, the connection to the brake carrier or the outer brake carrier horns is possible only with loss of brake caliper rigidity because of a reduced installation space.In a disc brake of the generic type, a respective brake pad holding spring is fastened to the brake pad carrier plates of the brake pads on the side facing away from the base of the brake pad shaft of the brake carrier and facing a mounting opening of the brake caliper, a holding bracket spanning the mounting opening in the displacement direction of the brake pads resting against said holding bracket, so that the brake pads are pressed against the base of the brake pad shaft.The pad retaining springs likewise oppose positioning of the restoring device meeting the requirements.DE 10 2014 019 618 A1 discloses a disc brake corresponding to the generic type, but without mentioning a restoring device. In order to prevent the brake pad from being clamped between the brake pad and the brake pad retaining clip during a brake actuation, a gap is provided between the pad carrier plate and the brake pad retaining spring in each position of the brake pad.Deviating from the generic type, JP 2002-39 239A discloses a disc brake in which brake pad retaining springs are positioned laterally on the pad carrier plate, which springs effect a prestress of the brake pad in correspondence with brake carrier horns of a brake carrier.CN 102 011 816B discloses a disc brake in which a pad-retaining clip has spring tongues which function in the sense of pad-retaining springs and which bear obliquely against the pad carrier plate.U.S. Pat. No. 4,410,069 A addresses a disc brake in which the prestressing of the respective brake pad is achieved by spring arms of a pad-retaining spring which is fastened as a leaf spring to a brake caliper.The invention is based on the object of further developing a disc brake and a brake pad of the generic type in such a way that the service life of the brake pads is increased and the operating costs are reduced overall by means of the simplest design means.This object is achieved by a disc brake having the features of claim 1 and by a brake pad having the features of claim 7.Compared to the prior art, the design according to the invention of both the disc brake and the brake lining offers considerable advantages. These result, among other things, from the extremely simple realization of the invention, since only the lining holding spring and / or the lining carrier plate of the brake lining have to be configured accordingly, which can be done essentially in a cost-neutral manner. The invention thus fulfills the constant requirement for cost optimization.Moreover, no particularly large-sized installation space is required for the configuration of the restoring device according to the invention, so that even disk brakes of a newer generation, which are distinguished by smaller installation space dimensions, can be equipped with a functional restoring device.According to a further development of the invention, the lining holding spring is arranged with its side facing the lining carrier plate parallel to the brake disc axis, while the lining carrier plate, according to the invention, is designed as a sloping slope towards the friction lining, wherein the lining carrier plate abuts in regions against the lining holding spring with a rear edge, with respect to the friction lining, in such a way that it is deformed against the spring force when the brake lining is displaced in the direction of the brake disc. The stored energy causes the brake pad to be moved back into its disengaged position when the brake is released.The embodiment according to the invention of both the lining retaining spring and the lining carrier plate is particularly advantageous, that is to say both mutually adjacent sides are designed as a slope, wherein here too, when the brake lining is displaced towards the brake disc, the lining retaining spring is tensioned in such a way that, when the brake is released, the brake lining is moved back into its starting position.The slope preferably extends at an angle, with respect to the central axis of the brake disc, at an acute angle of 10 to 30°, preferably of 15 to 25°, i.e. with respect to the planar rear side of the lining carrier plate, preferably between 60° and 80°, preferably between 65° and 75°.In this case, the slope of the lining holding spring in the contact region with the lining carrier plate can be formed by partial processing, for example by raising a correspondingly shaped tab, a ramp or the like. This too can be produced substantially without additional production costs.Further advantageous embodiments of the invention are characterized in the dependent claims.Exemplary embodiments of the invention are described below with reference to the attached drawings.The following are shown: FIG. 1 shows a disc brake according to the prior art in a plan viewFIGS. 2-4 show various exemplary embodiments of the disc brake according to the invention in each case in a schematic partial side view.FIG. 1 shows a disc brake according to the prior art, which is denoted overall by the reference sign 1.This disc brake has a brake caliper 2 which engages over a vehicle-side brake disc 9 and is mounted on a fixed brake carrier, from which brake carrier horns 4 can be seen, such that it can be axially displaced with respect to an axis A of the brake disc 9.Brake pads 3 are arranged in the brake carrier on both sides of the brake disc 9, which pads have a pad carrier plate 5 and a friction pad 6 fastened thereon.The brake pads 3 are each positioned in a pad shaft of the brake carrier, wherein each pad shaft is delimited in the direction of rotation of the brake disc 9 by the brake carrier horns 4.To avoid the generation of rattle noises, the brake pads 3 are held under prestress in the pad shafts, for which purpose a pad holding spring 7 is connected to a convexly shaped side of the respective pad carrier plate 5, on which spring a pad holding bracket 8 is supported, which spans an assembly opening of the brake caliper 2.FIGS. 2 to 4 show the configuration according to the invention of the disc brake 1 or of a brake pad 3 in different embodiment variants, the drawing figure being in schematic form of a lateral partial view.FIG. 2 shows the lining holding spring 7 with a side facing the brake lining 3 and running axially parallel to the axis of rotation A, while the lining carrier plate 5 is formed on the side facing the lining holding spring 7 as a slope 11 which runs inclined in the direction of the friction lining 6.Since the lining holding spring 7 is pressed down by the lining holding bracket 8, it is under spring tension, wherein the brake lining 3 is reproduced in the released position in FIG. 2.During a movement in the direction of the brake disc 9, the brake pad holding spring 7 is pressed against the slope 11, wherein it is placed under such a prestress that during the subsequent release by the spring forces the brake pad 3 is displaced into a release position.In FIG. 3, the lining holding spring 7 is rotated in accordance with the inclination of the slope 11 of the lining carrier plate 5, so that after a relative movement of the brake lining 3 during braking, the lining holding spring 7 is tensioned and after releasing the brake, the brake lining 3 is returned to a released position by the effective spring forces.In the exemplary embodiment shown in FIG. 4, a tab 10 is provided on the lining holding spring 7 in a manner corresponding to the slope 11 and contacts the slope 11 and deforms the lining holding spring 7 in the previously described sense.In this case, the brake lining 3 is held displaceably relative to the lining holding spring 7 parallel to the axis A of the brake disc 9.The slope preferably extends at an angle α, with respect to the central axis of the brake disc, at an acute angle of 10 to 30°, preferably of 15 to 25°, i.e. with respect to the planar rear side of the lining carrier plate, preferably between 60° and 80°, preferably between 65° and 75°.List of reference characters1 Disc brake 2 Brake caliper 3 Brake pad 4 Brake carrier pad 5 Pad carrier plate 6 Friction pad 7 Pad retaining spring 8 Pad retaining clip 9 Brake disc 10 Tab 11 Slope A Axis α Angle

Claims

Disc brake (1) for a commercial vehicle, having a brake caliper (2) which engages over a brake disc (9) and is designed as a sliding caliper, two brake pads (3) which are arranged therein and can be moved in opposite directions in the direction of the brake disc (9) and each have a pad carrier plate (5) and a friction pad (6) fastened thereon and which are each arranged under prestress by means of a pad retaining spring (7) on which a pad retaining clip which spans an assembly opening of the brake caliper (2) is supported, in a pad shaft of a vehicle-side brake carrier which is bounded by brake carrier horns (4) in the direction of rotation of the brake disc (9), and having resetting devices by means of which the brake pad (3) can be returned after a brake-dependent displacement and release of the brake, characterized in that, at least one of the mutually facing and contacting regions of the lining carrier plate (5) and / or of the lining retaining spring (7) is designed as a slope (11) which slopes downwards towards the friction lining (6).Disc brake (1) according to claim 1, characterised in that the pad holding spring (7) and the pad carrier plate (5) are displaceable relative to one another in the displacement direction of the brake pad (3).Disc brake (1) according to claim 1 or 2, characterised in that the pad holding spring (7) is rotated in the contact region with the pad carrier plate (5) forming an inclination running in the same way to the inclination (11) of the pad carrier plate (5).Disc brake (1) according to one of the preceding claims, characterised in that the slope (11) of the pad-retaining spring (7) is formed by an integrally formed lug (10) or ramp.Disc brake (1) according to one of the preceding claims, characterized in that the slope (11), with respect to the planar rear side of the pad carrier plate (5), extends at an angle (α) of between 60° and 80°.Disc brake (1) according to one of the preceding claims, characterized in that the slope (11), with respect to the planar rear side of the pad carrier plate (5), extends between an angle (α) of 65° to 75°.Brake pad for a disc brake of a commercial vehicle, having a pad carrier plate (5) and a friction lining (6) fastened thereon, wherein the pad carrier plate (5) is convexly curved on one side and a pad retaining spring (7) is arranged on the convex side, characterized in that the convexly curved side of the pad carrier plate (5) is designed, at least in regions, as a slope (11) which slopes downward towards the friction lining (6), wherein the pad retaining spring (7) contacts the pad carrier plate (5) in the region of the slope (11).

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