Electromechanical brake

Abstract

The invention relates to an electromechanical brake (10) for a motor vehicle. The electromechanical brake (10) comprises a brake caliper (14) which forms a housing (22) in which a spindle drive (26) is arranged, which can be driven by a drive motor (86), so that a brake piston (50) can apply an axial braking force (F). B ) is movable. The brake caliper (14) is formed in one piece and provides an axial support (48) for the spindle drive (26) as well as a brake caliper (18), so that the braking force (F B ) as well as one of the braking force (F B ) opposing support force (F A ) are taken up by the brake caliper (14).

Description

[0001] The present invention relates to an electromechanical brake for a motor vehicle. Such an electromechanical brake comprises a brake caliper forming a housing in which a spindle drive is arranged, which can be driven by a drive motor, so that a brake piston can be moved to apply an axial braking force. State of the art

[0002] Typically, the service brake is a brake in which a brake piston, together with a brake pad, is pressed onto a brake disc via brake fluid to slow the vehicle. With the increasing electrification of motor vehicle components, the service brake is also being designed as an electromechanical brake, eliminating the need for brake fluid and the associated complex valve and line assembly. Such an electromechanical brake could also significantly reduce maintenance requirements.

[0003] EP 1 030 979 B1 discloses an electromechanical braking device for braking a motor vehicle wheel. The braking device comprises a brake caliper in which an electric motor is arranged. The electric motor drives a spindle drive unit, via which brake pads arranged on a brake caliper of the brake caliper can be applied to a brake disc for braking.

[0004] The object underlying the invention is to provide an electromechanical brake for a motor vehicle which is optimized with regard to manufacturing costs and weight.

[0005] The object is achieved by an electromechanical brake having the subject matter of patent claim 1. Preferred embodiments can be found in the dependent claims. Disclosure of the invention

[0006] The invention specifies an electromechanical brake for a motor vehicle. The electromechanical brake comprises a brake caliper forming a housing in which a spindle drive is arranged, which can be driven by a drive motor, so that a brake piston can be moved to apply an axial braking force. The brake caliper is formed as a single piece and forms an axial support for the spindle drive as well as a brake caliper, so that the braking force and a supporting force counteracting the braking force are absorbed by the brake caliper.

[0007] According to the invention, a housing is formed by the brake caliper. The housing is preferably formed as a bore in the brake caliper. This eliminates the need for a separate housing to be attached to the brake caliper, thus saving weight for fasteners and a connection interface. Due to the one-piece design of the brake caliper, no fasteners are required to connect the various brake caliper parts. This improves force transmission within the brake caliper. In particular, this eliminates the need for material reinforcement in the connection area, thus saving material here as well.

[0008] According to the invention, the axial support for the spindle drive is also formed by the one-piece brake caliper. Accordingly, connecting means for a separate support element can be dispensed with here as well. Due to the corresponding design of the brake caliper, the braking forces absorbed by the brake caliper as well as the equally large but opposing supporting forces absorbed by the axial support are completely absorbed by the brake caliper. Thus, only a single component needs to be manufactured. Overall, this reduces the manufacturing costs and weight of the electromechanical brake. Additional work steps for attaching an axial support are eliminated.

[0009] In a preferred embodiment of the invention, the brake caliper of the brake caliper has a recess through which the spindle drive and the brake piston can be inserted into the housing formed by the brake caliper. A recess in the brake caliper has the advantage that the spindle drive and the brake piston can be more easily inserted into the brake caliper housing. This simplifies assembly of the electromechanical brake.

[0010] In a further preferred embodiment of the invention, an anti-rotation device for the spindle drive is formed by the brake caliper. Thus, no additional parts or associated connecting elements are required to form an anti-rotation device. The anti-rotation device is preferably designed in the form of a slot in the brake caliper.

[0011] Preferably, at least one separate inner part is introduced into the brake caliper, via which at least one anti-twist device for the spindle drive is formed. By forming a separate part as the anti-twist device, the manufacture of the anti-twist device is simplified. An undercut, which is difficult to form on the brake caliper, can thereby be avoided. It is also possible to use a different material for the anti-twist device than the brake caliper. Since such an anti-twist device does not have to absorb high forces, a less rigid material can be used, which is also lighter. It is also possible, for example, to use a plastic for the anti-twist device, which further simplifies production by injection molding. It is also possible to select a plastic with improved sliding properties, so that a piston guide can be guided in the anti-twist device with little resistance.

[0012] Advantageously, the separate inner part is connected to the brake caliper either force-fitting or form-fitting. The inner part is thus held in the brake caliper without the need for additional fasteners, saving weight for fasteners. Advantageously, the force-fitting connection is formed by a press fit. Such connections are easy to form. It is also possible to create a connection using form-fitting elements.

[0013] In another advantageous embodiment, the drive motor is mounted directly on the brake caliper. This eliminates the need for a separate housing for the drive motor. This eliminates the need for an additional work step for attaching a separate housing to the brake caliper.

[0014] According to a practical embodiment, the area of ​​the one-piece brake caliper to which the drive motor is attached has several mounting surfaces for the drive motor, aligned at different angles to one another, so that the drive motor can be attached to the brake caliper in various mounting positions. The motor can be attached to each of the mounting surfaces. Advantageously, the mounting surfaces are distributed around a rotational axis of the spindle drive. The mounting surfaces can be designed such that a polygon is formed on the brake caliper. Thanks to the various mounting surfaces, the motor can be arranged according to the installation space available on the motor vehicle. This means that only a single brake caliper needs to be provided, which can be adapted to various installation situations.The electromechanical brake is therefore versatile, so that development and manufacturing costs can be saved for different installation situations.

[0015] According to another advantageous embodiment, a drive gear that interacts with the spindle drive is arranged in the housing formed by the brake caliper. Thus, a separate drive gear housing is not required. This also eliminates the need for a separate work step for attaching such a housing to the brake caliper. This also saves weight for the required connecting elements.

[0016] Preferably, a parking brake is arranged in the housing formed by the brake caliper. By forming a parking brake, the electromechanical brake also provides a parking brake function. This eliminates the need for a separate parking brake.

[0017] Advantageously, a drive gear that interacts with the spindle drive is housed in a gear housing mounted on the brake caliper. By constructing the gear housing separately from the brake caliper, a different material can be used for the gear housing than for the brake caliper. Since the load on the gear housing is significantly lower than that on the brake caliper, a lighter and more cost-effective material can be used for the gear housing. Constructing the gear in a separate housing also makes the brake caliper easier to manufacture.

[0018] The invention additionally provides a motor vehicle having such an electromechanical brake. Such a motor vehicle has the effects and advantages described above.

[0019] Embodiments of the invention are illustrated in the drawing and explained in more detail in the following description. It shows: Fig. 1 sectional view of an electromechanical brake according to a first embodiment of the invention, Fig. 2 Sectional view of an electromechanical brake according to a second embodiment of the invention, Fig. 3 Sectional view of an electromechanical brake according to a third embodiment of the invention, Fig. 4 Section through the brake calliper of the electromechanical brake from Fig. 3, and Fig. 5 Perspective view of an embodiment of the brake caliper.

[0020] In Fig. Figure 1 is a sectional view of an electromechanical brake 10 according to a first embodiment of the invention. The electromechanical brake 10 comprises a brake caliper 14, which forms a brake caliper 18, and a housing 22. A spindle drive 26, which in this embodiment is designed as a ball screw drive, is arranged in the housing 22. The spindle drive 26 comprises a spindle 30 and a spindle nut 34, which is axially displaceable upon rotation of the spindle 30.

[0021] The spindle 30 has a spindle ring groove 38 in which a support part 42 is arranged. The support part 42 has a cylindrical portion 42a and a portion having an outer diameter D Sthe spindle 30 has a collar 42b projecting beyond it. The cylindrical portion 42a and the collar 42b bear against an angular contact ball bearing 46 arranged in the housing 22 of the brake caliper 14. The spindle 30 is rotatably mounted in the housing 22 via the support part 42 and the angular contact ball bearing 46. The angular contact ball bearing 46 is held in the axial direction by a radially inwardly projecting axial support 48 of the brake caliper 14, so that a braking force F B opposing support force F A is received by the brake caliper 14.

[0022] The spindle nut 34 is firmly connected to a brake piston 50, via which the braking force F B can be applied to a brake disc (not shown). The braking force F applied by the brake piston 50 Bis received by the brake caliper 18 formed by the brake caliper 14. To prevent rotation of the spindle nut 34, the brake piston 50 forms radially extending anti-rotation guides 54. The anti-rotation guides 54 engage with anti-rotation devices 58 formed by the brake caliper 14. The anti-rotation devices 58 formed by the brake caliper 14 are designed as axially extending slots. The brake caliper 14 additionally forms annular grooves 62 for a piston seal 66 and a piston guide 70.

[0023] The brake caliper 18 has a central recess 74, via which the spindle drive 26 and the brake piston 50 can be mounted from the brake caliper 18. A perspective view of the brake caliper 18 with the recess 74 is shown in Fig. 5 shown. Fig. 1 additionally shows that a separate gear housing 78 is attached to the brake caliper 14, in which a drive gear 82 for the spindle drive 26 is arranged. In the exemplary embodiment, the drive gear 82 is designed as a worm gear. To drive the drive gear 82 and thus the spindle drive 26, a drive motor 86 is arranged on the separate gear housing 78.

[0024] Fig. Figure 2 shows a sectional view of an electromechanical brake 10 according to a second embodiment of the invention. This embodiment differs from that shown in Fig. 1 in that the anti-rotation device 58 and the annular grooves 62 for the piston seal 66 and the piston guide 70 are not formed in the brake caliper 14. The anti-rotation device 58 is formed by a separate inner part 90, which is inserted into the housing 22. The separate inner part 90 can be connected to the brake caliper 14 via a press fit. The separate inner part 90 has the slot for the anti-rotation guide 54, so that the brake piston 50 and thus the spindle nut 34 are secured against rotation. In addition, in this exemplary embodiment, a second inner part 94 is arranged in the brake caliper 14, via which the annular grooves 62 for the piston seal 66 and the piston guide 70 are formed. In a further exemplary embodiment not shown, the two inner parts 90, 94 can also be designed as a common inner part.

[0025] In Fig. 3 shows a sectional view of an electromechanical brake 10 according to a third embodiment of the invention. This embodiment differs from the embodiments of Fig. 1 and Fig. 2 in that the drive gear 82 is not arranged in a separate gear housing 78. Rather, the gear housing 78 is formed as a single piece by the brake caliper 14. The housing 22 for the drive gear 82 is merely closed by a separate gear housing cover 98. A parking brake 100 is also arranged in the housing 22 for the drive gear 82, which blocks the drive gear 82 during parking, so that the brake can be kept applied during the parking process. The drive motor 86 and a control unit 102 for the electromechanical brake 10 are arranged on the housing 22 formed by the brake caliper 14.

[0026] Fig. 4 shows a section through the brake calliper 14 of the electromechanical brake of Fig. 3. This figure shows that the housing 22 for the drive gear 82 has a plurality of mounting surfaces 106 for the drive motor 86 and the control unit 102. The mounting surfaces 106 are aligned differently. Examples of how the drive motor 86 and the control unit 102 can also be arranged are shown in dashed lines. The drive motor 86 and the control unit 102 can thus be arranged differently depending on the required installation situation. As a result, only one version of the brake caliper 14 is necessary for different arrangements of the drive motor 86 and the control unit 102 on the brake caliper 14. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This 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

[0000] EP 1 030 979 B1

[0003]

Claims

[1] Electromechanical brake (10) for a motor vehicle, comprising a brake calliper (14) which forms a housing (22) in which a spindle drive (26) is arranged, which can be driven via a drive motor (86), so that a brake piston (50) for applying an axial braking force (F B ) is movable, characterized by that the brake calliper (14) is formed in one piece and forms an axial support (48) for the spindle drive (26) as well as a brake calliper (18), so that the braking force (F B ) as well as one of the braking force (F B ) opposing support force (F A ) are received by the brake calliper (14). [2] Electromechanical brake (10) according to claim 1, characterized by that the brake calliper (18) of the brake calliper (14) has a recess (74) through which the spindle drive (26) and the brake piston (50) can be introduced into the housing (22) formed by the brake calliper (14). [3] Electromechanical brake (10) according to claim 1 or 2, characterized by that an anti-twist device (58) for the spindle drive (26) is formed by the brake calliper (14). [4] Electromechanical brake (10) according to claim 1 or 2, characterized by that at least one separate inner part (90) is introduced into the brake calliper (14), via which at least one anti-twist device (58) for the spindle drive (26) is formed. [5] Electromechanical brake (10) according to claim 4, characterized by that the separate inner part (90) is connected to the brake calliper (14) in a force-locking or form-locking manner. [6] Electromechanical brake (10) according to one of the preceding claims, characterized by that the drive motor (86) is attached to the brake calliper (14). [7] Electromechanical brake (10) according to claim 6, characterized bythat a region of the one-piece brake calliper (14) to which the drive motor (86) is mounted has a plurality of mounting surfaces (106) for the drive motor (86) aligned at different angles to one another, so that the drive motor (86) can be mounted in different mounting positions on the brake calliper (14). [8] Electromechanical brake (10) according to one of the preceding claims, characterized by that a drive gear (82) cooperating with the spindle drive (26) is arranged in the housing (22) formed by the brake calliper (14). [9] Electromechanical brake (10) according to claim 8, characterized by that a parking brake (100) is arranged in the housing (22) formed by the brake calliper (14). [10] Electromechanical brake (10) according to one of claims 1 to 5, characterized bythat a drive gear (82) cooperating with the spindle drive (26) is arranged in a gear housing (78) arranged on the brake calliper (14). [11] Motor vehicle comprising an electromechanical brake (10) according to one of the preceding claims.

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