disc brake system

Abstract

Disc brake system (100) comprising a piston (102) and a brake pad (104), wherein the piston (102) and the brake pad (104) are mechanically connected to each other via a fastening assembly (112), wherein the fastening assembly (112) is configured to limit a relative movement between the piston (102) and the brake pad (104) with respect to an actuation direction (A) of the piston (102), wherein the fastening assembly (112) comprises: two guide elements (212.1.1, 212.1.2) in the form of a circular arc and two fastening elements (212.2.1, 212.2.2), each of which is attached to one of the guide elements (212.1.1, 212.1.2) and is configured to limit a relative movement of the guide element (212.1.1, 212.1.2) with respect to the respective fastening element (212.2.1, 212.2.2) in the actuation direction (A) of the piston, and wherein the two fastening elements (212.2.1, 212.2.2) are encompassed by the piston (202) and are designed as pins, each with a wide head and a narrow body and wherein the two guide elements (212.1.1, 212.1.2) are both arc-shaped, and each of the guide elements (212.1.1, 212.1.2) has a wide entry section (212.1.1w) and a narrow locking section (212.1.1n).

Description

[0001] This revelation refers to a disc brake system with one piston and one brake pad.

[0002] Automakers are forcing brake suppliers to solve the most significant problems of disc brake systems: squealing noises, drag torque, increased component mass, pedal travel, and brake and disc dust. Reducing drag torque, in particular, is proving to be a difficult problem.

[0003] Drag torque is caused by both residual resistance and the suction effect of the brake pads. Residual resistance describes a partial and temporary contact between the brake disc and brake pads while driving. Suction, on the other hand, describes a permanent contact between the brake disc and brake pads, whereby the brake pads are drawn against a surface of the brake disc.

[0004] One approach to reducing residual resistance is the use of a return spring, which uses the spring effect to return the brake pads to a starting position after the braking phase.

[0005] DE 10 2015 223555 A1 discloses a brake pad guide for reducing frictional resistance in a brake caliper installed in a vehicle brake. The brake pad guide is installed in the brake caliper to adjust the spring force so that the brake pads are kept apart from the brake disc.

[0006] While the use of a spring can be useful in reducing drag torque, it also requires the installation of additional parts in a disc brake system, which adds weight and manufacturing costs.

[0007] Further relevant disclosures from the prior art can be found in documents JP 2019-173870 A, DE 11 2015 003 544 T5, JP 2012-092968 A, DE 10 2012 009 901 A1, DE 696 21 032 T2, DE 102012 012 844 A1, DE 196 01 435 A1, JP H07-158 668 A and US 2018 / 0 094 682 A1.

[0008] The purpose of this disclosure is to describe an alternative approach to reducing drag resistance. This purpose is achieved by the disc brake system according to claim 1.

[0009] The disc brake system comprises in particular a piston and a brake pad, wherein the piston and the brake pad are mechanically connected to each other by a fastening assembly and wherein the fastening assembly is configured to limit a relative movement between the piston and the brake pad with respect to an actuation direction of the piston.

[0010] The mounting assembly reduces drag torque because it allows the brake pad to be pulled away from the disc brake system's brake disc after braking by the piston's retraction. Furthermore, as a result of the reduced drag torque, the disc brake system, according to the present disclosure, can also contribute to reducing material wear, overall fuel consumption, noise, and brake dust generation. The proposed modification to the disc brake system also requires no additional parts.

[0011] Preferred embodiments of the disc brake system are described below.

[0012] In a preferred embodiment, the fastening assembly is arranged to restrict the relative movement in such a way that the clearance with respect to the relative movement of the piston and the brake pad in the actuation direction is limited to less than 0.2 mm, in particular 0.1 mm.

[0013] In another preferred embodiment, the fastening assembly is additionally or alternatively arranged to allow a relative rotational movement between the piston and the brake pad in a plane perpendicular to the actuation direction of the piston.

[0014] The mounting assembly comprises a guide element in the form of a circular arc and a fastening element attached to the guide element. In this embodiment, the fastening element is configured to restrict relative movement of the guide element with respect to the fastening element in the actuation direction of the piston.

[0015] The following describes various variants of the embodiment, which includes the fastening assembly with the guide element and the fastening element.

[0016] In a variant of this embodiment, comprising a guide element and a fastening element, the fastening element is arranged to move along the guide element in order to enable a relative rotational movement between the piston and the brake pad in a plane perpendicular to the actuation direction of the piston.

[0017] In another variant, the guide element is additionally or alternatively formed at least partially by a groove in a surface, and the fastening element is inserted at least partially into the groove.

[0018] In another variant, the guide element is additionally or alternatively formed at least partially by a raised section on a surface, and the fastening element is arranged along the raised section and / or covers the raised section.

[0019] In another variant, the guide element is additionally or alternatively circular in shape.

[0020] In another variant, the guide element and the fastening element are shaped in such a way that the fastening element is attached to the guide element by a positive locking connection.

[0021] In another variant, the fastening element is additionally or alternatively attached to the guide element via a snap connection and / or an undercut.

[0022] In another variant, the fastening assembly additionally or alternatively comprises a large number of guide elements and a large number of corresponding fastening elements.

[0023] In another variant, which includes a multitude of guide elements and a multitude of corresponding fastening elements, the multitude of guide elements are additionally or alternatively arranged on a fastening surface along two or more concentric circles.

[0024] In all described embodiments, the guide element and the fastening element can be arranged on the piston or on the brake pad.

[0025] In another variant, the guide element is additionally or alternatively circular in shape. In one embodiment of this variant, the guide element is designed as a half-circle arc. In another embodiment, the guide element is designed as a different fraction of a circle arc.

[0026] In a preferred embodiment, the disc brake system is additionally or alternatively designed for use in a passenger car.

[0027] In the following, various embodiments of the disc brake system according to the present disclosure are described with reference to the figures. First, a brief summary of the figures will be given. It should be noted that not all features of the claimed subject matter are shown in all figures, and the Fig. 4a and Fig. 4b refers to an unused version of a disc brake system. Fig. Figure 1 shows a side view of a disc brake system comprising a mounting assembly; Fig. 2a shows a side facing the brake pad of the in Fig. 1 piston shown; Fig. 2b shows a piston-facing side of the in Fig. 1 brake pad shown; Fig. Figure 2c shows a cross-sectional view of a piston and a brake pad of the disc brake system. Fig. 1 in an exploded view, wherein the piston and the brake pad are attached to each other by means of the fastening assembly; Fig. 2D shows an enlarged view of the in Fig. 2c cross-sectional view shown; Fig. Figure 2e shows an enlarged section of Fig. 2c, which shows the mounting assembly comprising the piston and brake pad; Fig. Figure 3a shows a brake pad-facing side of a piston, which includes two fastening elements; Fig. Figure 3b shows a piston-facing side of a brake pad, which is connected to the in Fig. 3a corresponds to the piston shown and comprises two guide elements; Fig. Figure 4a shows a brake pad-facing side of a piston, which includes two guide elements; and Fig. Figure 4b shows a piston-facing side of a brake pad, which is connected to the in Fig. 4a corresponds to the piston shown and comprises two guide elements.

[0028] The following is a detailed description of the embodiments shown in the figures. The description begins with a description of a first embodiment of the disc brake system as proposed in the present disclosure and refers to Fig. 1 and Fig. 2a-d.

[0029] Fig. Figure 1 shows a side view of a disc brake system 100, which includes a fastening assembly 112.

[0030] Disc brake system 100 comprises a piston 102 and a brake pad 104, wherein the piston 102 and the brake pad 104 are mechanically connected to each other via a fastening assembly 112, wherein the fastening assembly 112 is configured to limit a relative movement between piston 102 and brake pad 104 with respect to an actuation direction A of the piston 102.

[0031] In the Fig. In the embodiment shown in Figure 1, the disc brake system 100 is a floating caliper disc brake system for a motor vehicle. However, other embodiments of the disc brake system can also be used for other vehicles. The disc brake system 100 comprises a brake disc 108. The actuation direction A is approximately parallel to a plane in which the brake disc 108 lies. Thus, the actuation direction A is approximately parallel to an axis of a motor vehicle when the disc brake system 100 is mounted.

[0032] The disc brake system 100 comprises a floating caliper with a caliper housing 110. In the floating caliper arrangement shown, the piston is located on one side of the brake disc 108 that, when installed in the car, is closer to the interior of the vehicle. The brake pad 104 is therefore often referred to as the inner brake pad. On the opposite side of the brake disc 108, the disc brake system 100 includes another brake pad 106, which is frequently referred to as the outer brake pad. However, other embodiments of the disc brake system may also include a fixed brake caliper. In fixed brake caliper arrangements, pistons with corresponding brake pads are located on both sides of the brake disc 108. The mounting assembly 112, which is described in detail below, can be used with pistons and brake pads on both sides of the brake disc.

[0033] The mounting assembly 112 of the disc brake system 100 is designed to allow a relative rotational movement between the piston 102 and the brake pad 104 in a plane perpendicular to the actuation direction A of the piston 102.

[0034] Details regarding a possible implementation of the fastening assembly are provided below with reference to Fig. 2a-2d described.

[0035] Fig. Figure 2c shows a cross-sectional view of the piston 102 and the brake pad 104 of the disc brake system 100. Fig. 1 in an exploded view, wherein the piston 102 and the brake pad 104 are attached to each other by means of the fastening assembly 112. Fig. 2a shows a brake pad-facing side of piston 102 from Fig. 1. Fig. 2b shows a piston-facing side of the brake pad 104. Fig. 1.

[0036] The mounting assembly 112 comprises a guide element 112.1 in the form of a circular arc, in particular in the form of a full circle. Furthermore, the mounting assembly 112 comprises a fastening element 112.2, which is attached to the guide element 112.1 when installed in the disc brake system 100, and is configured to limit the relative movement of the guide element 112.1 with respect to the fastening element 112.2 in the actuation direction A of the piston 102.

[0037] In the Fig. In the embodiment shown in Figures 2a-2c, the guide element 112.1 is arranged on a piston-facing side of the brake pad 104, and the fastening element 112.2 is arranged on a brake pad-facing side of the piston 102. The brake pad 104 comprises a back plate 104.2 and a friction material 104.1 attached to the back plate 104.2. The guide element 112.1 is arranged on a piston-facing side of the back plate 104.2.

[0038] Fig. Figure 2e shows an enlargement of a section E from Fig. 2a, which shows the mounting assembly 112 comprising the pistons 102 and brake pad 104.

[0039] As from Fig. As can be seen in Figure 2c, the guide element 112.1 is formed by a groove in a surface on the side of the back plate 104.2 facing the piston, and the fastening element 112.2 is inserted into the groove when it is fully installed in the disc brake system 100. In the case described in the Fig. In the embodiment shown in Figures 2a-2e, the fastening element 112.2 is connected to the guide element 112.1 by a positive-locking connection. Specifically, the fastening element 112.2 is attached to the guide element 112.1 via a snap-fit ​​connection formed by a flexible projection 112.2.1 and a corresponding recess 112.1.1. This design allows the fastening element 112.2 to move along the guide element 112.1, enabling a relative rotational movement between the piston 102 and the brake pad 104 about a plane perpendicular to the actuation direction A of the piston 102. Due to the circular shape of the guide element 112.1, the fastening assembly 112 is particularly suitable for use with a piston that does not include an anti-rotation mechanism. The circular shape allows for continuous rotation of the piston about its axis of symmetry.However, other embodiments use different connections, in particular other positive-locking connections, to attach the piston to the brake pad.

[0040] Fig. 2D shows an enlarged view of the in Fig. The cross-sectional view shown in Figure 2c is shown. In this magnified view, the guide element 112.1 of the brake pad 104 and the fastening element 112.2 of the piston 102 are depicted. A shape of the fastening element 112.2 and a shape of the guide element 112.1, including the snap connection (not visible in the figure), are chosen such that an axial gap 112.4 between the fastening element 112.2 and the guide element 112.1 is small in order to limit the relative movement between the piston 102 and the brake pad 104 with respect to the actuation direction A of the piston 102. At the same time, the shape of the fastening element 112.2 and the shape of the guide element 112.1 are chosen such that a radial gap 112.3 between the fastening element 112.2 and the guide element 112.1 is sufficiently large to allow the relative rotational movement between the piston 102 and the brake pad 104 in a plane perpendicular to the actuation direction A of the piston 102.

[0041] For the axial gap 112.4, a clearance of less than 0.2 mm, and in particular less than 0.1 mm, is preferred. With respect to the radial gap 112.3, a clearance greater than 0.1 mm is recommended.

[0042] In the embodiment of the fastening assembly 112 in the Fig. In 2a-e, the guide element 112.1 and the fastening element 112.2 have a circular shape, so that one of the two elements can guide the other. Therefore, the naming in this example could also be reversed.

[0043] Fig. Figure 3a shows a brake pad-facing side of a piston 202, which includes two fastening elements 212.2.1 and 212.2.2. Fig. Figure 3b shows a brake pad facing side of a corresponding brake pad 204, which includes two guide elements 212.1.1 and 212.1.2.

[0044] The piston 202 and the brake pad 204 can be used in the disc brake system 100 instead of the piston 102 and the brake pad 104.

[0045] The guide elements 212.1.1 and 212.1.2 are both arc-shaped. The guide element 212.1.1 comprises a wide entry section 212.1.1w and a narrower locking section 212.1.1n, the narrower locking section having an undercut (not shown). The guide element 212.1.2 is identically shaped.

[0046] The piston 202 comprises two fastening elements 212.2.1 and 212.2.2, which are designed as pins, each with a wide head and a narrow body. The wide head of the pins 212.2.1 and 212.2.2 is shaped such that each pin 212.2.1 and 212.2.2 can enter the guide elements 212.1.1 and 212.1.2 through the entry section 212.1.1w. The fastening elements 212.2.1 and 212.2.2 can then be securely fastened to the guide elements 212.1.1 and 212.1.2 by rotating the piston 202 and the brake pad 204 relative to each other so that each pin is moved into the narrow section of the guide element 212.1.1 or 212.1.2, respectively.

[0047] The fastening assembly 212 is particularly suitable for pistons with an anti-rotation mechanism, since the guide elements 212.1 and 212.2 do not allow a full 360° rotation of the piston 202.

[0048] In Fig. 3a and Fig. 3b the guide elements 212.1.1 and 212.1.2 are part of the brake pad 204 and the fastening elements 212.2.1 and 212.2.2 are part of the piston 202.

[0049] Fig. Figure 4a shows a brake pad-facing side of a piston 302, which includes two fastening elements 312.1.1 and 312.1.2. Fig. Figure 4b shows a piston-facing side of a corresponding brake pad 304, which includes two guide elements 312.2.1 and 312.2.2.

[0050] The piston 302 and the brake pad 304 can be used in the disc brake system 100 instead of the piston 102 and the brake pad 104.

[0051] In summary, the present disclosure describes a disc brake system (100) comprising a piston (102) and a brake pad (104), wherein the piston (102) and the brake pad (104) are mechanically connected to each other via a fastening assembly (112), wherein the fastening assembly (112) is configured to limit a relative movement between the piston (102) and the brake pad (104) with respect to an actuation direction (A) of the piston (102).

Claims

[1] A disc brake system (100) comprising a piston (102) and a brake pad (104), wherein the piston (102) and the brake pad (104) are mechanically connected to one another via a fastening assembly (112), wherein the fastening assembly (112) is configured to limit a relative movement between the piston (102) and the brake pad (104) with respect to an actuation direction (A) of the piston (102), wherein the fastening assembly (112) comprises: two guide elements (212.1.1, 212.1.2) in the form of a circular arc and two fastening elements (212.2.1, 212.2.2), each of which is fastened to one of the guide elements (212.1.1, 212.1.2) and is arranged to limit a relative movement of the guide element (212.1.1, 212.1.2) with respect to the respective fastening element (212.2.1, 212.2.2) in the actuating direction (A) of the piston, and wherein the two fastening elements (212.2.1, 212.2.2) are encompassed by the piston (202) and are designed as pins, each with a wide head and a narrow body, and wherein the two guide elements (212.1.1, 212.1.2) are both arcuately shaped, and each of the guide elements (212.1.1, 212.1.2) has a wide entry section (212.1.1w) and a narrow locking section (212.1.1n). [2] Disc brake system (100) according to claim 1, wherein the mounting assembly (112) is configured to allow relative rotational movement between the piston (102) and the brake pad (104) in a plane perpendicular to the actuation direction (A) of the piston (102). [3] Disc brake system (100) according to claim 1 or 2, wherein the fastening element (112.2) is arranged to move along the guide element (112.1) to enable a relative rotational movement between the piston (102) and the brake pad (104) in a plane perpendicular to the actuation direction (A) of the piston (102). [4] Disc brake system (100) according to one of the preceding claims, wherein the guide element (112.1) is at least partially formed by a groove in a surface and the fastening element (112.2) is at least partially inserted into the groove. [5] Disc brake system (100) according to one of the preceding claims, wherein the guide element (112.1) is at least partially formed by an elevation on a surface and the fastening element (112.2) is arranged along the elevation and / or covers the elevation. [6] Disc brake system (100) according to one of the preceding claims, wherein the guide element (112.1) is circular. [7] Disc brake system (100) according to one of the preceding claims, wherein the guide element (112.1) and the fastening element (112.2) are shaped such that the fastening element (112.2) is fastened to the guide element (112.1) by a positive connection. [8] Disc brake system (100) according to one of the preceding claims, wherein the fastening element (112.2) is fastened to the guide element (112.1) via a snap connection and / or an undercut. [9] Disc brake system (100) according to one of the preceding claims, wherein the fastening assembly (212) comprises a plurality of guide elements (212.1.1, 212.1.2) and a plurality of respective fastening elements (212.2.1, 212.2.2). [10] Disc brake system (100) according to claim 9, wherein the plurality of guide elements (212.1.1, 212.1.2) are arranged on a mounting surface along two or more concentric circles. [11] Disc brake system (100) according to one of claims 1 to 10, wherein the fastening element (212.1.1, 212.1.2) is arranged on a side of the piston (202) facing the brake pad and the guide element (212.2.1, 212.2.2) is arranged on a side of the brake pad (204) facing the piston.

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