Electromechanical brakes and automobiles having motor cases manufactured by a cup extrusion step.

Abstract

We provide electromechanical brakes for automobiles. [Solution] An electromechanical brake for an automobile has an electric motor, which rotates a spindle drive unit located within the brake caliper housing, and a brake controller is slidable axially within the brake caliper housing to apply braking force. A motor case located within the brake caliper housing houses the electric motor, and a control unit housing for a control unit that controls the electric motor is located within the motor case. The motor case is formed from a metal material, which forms a bowl-shaped housing space in which the electric motor is housed. The motor case is closed via the control unit housing, and the motor case is formed by a cup extrusion molding step.

Description

Technical Field

[0001] The present invention relates to an electromechanical brake for an automobile and an automobile having such an electromechanical brake.

Background Art

[0002] Generally, a foot brake is a brake that presses a brake piston together with a brake lining against a brake disk via brake fluid to brake an automobile. As devices in an automobile are becoming increasingly electrified, the foot brake should also be configured as an electromechanical brake, whereby the brake fluid and the expensive valves and pipeline structures belonging to the brake fluid can be omitted. Similarly, such an electromechanical brake can significantly reduce maintenance costs.

[0003] Patent Document 1 describes a brake caliper for a disc brake. This brake caliper has a brake caliper housing, and a transmission housing is arranged in this brake caliper housing. A controller housing is attached to the rear side of the transmission housing, and a motor and a brake control unit for controlling this motor are accommodated in this controller housing.

[0004] Patent Document 2 describes an electromechanically operable disc brake for automobiles. The electromechanically operable disc brake has a caliper housing which grips a brake disc. The caliper housing has a housing-shaped notch in which the brake motor is located. A speed-increasing gear transmission is located above the motor and the caliper housing, and a spindle drive unit located inside the caliper housing is driven via this speed-increasing gear transmission. A circuit device carrier for a control unit is provided above the speed-increasing gear transmission, and the motor can be controlled via this control unit. The circuit device carrier and the speed-increasing gear transmission are closed off from the outside via a cover. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2023 / 166434 brochure [Patent Document 2] German Patent Publication No. 102009046044 [Overview of the project] [Problems that the invention aims to solve]

[0006] The object of the present invention is to provide an electromechanical brake for automobiles that can be manufactured simply and economically, and is well protected against environmental conditions such as dirt and moisture. [Means for solving the problem]

[0007] This problem is solved by an electromechanical brake having the subject matter of claim 1. Preferred embodiments are described in the dependent claims.

[0008] The present invention provides an electromechanical brake for an automobile. This electromechanical brake has an electric motor, which rotationally drives a spindle drive unit located within the brake caliper housing, thereby allowing a brake controller to slide axially within the brake caliper housing to apply braking force. The electric motor is housed in a motor case located within the brake caliper housing, and a control unit housing for a control unit that controls the electric motor is housed within this motor case. The motor case is formed from a metal material, which forms a bowl-shaped housing space in which the electric motor is housed. The motor case is closed via the control unit housing, which is formed by a cup extrusion molding step.

[0009] The bowl-shaped housing space can be interpreted as a space formed with only one axial end open. According to the present invention, the motor case only needs to be protected from the ingress of dirt and moisture at the axial end. Therefore, only a few sealing points are required. At this axial end, the motor case is closed via the control unit housing. Therefore, a separate lid is not required to close the motor case. This can reduce the number of parts and weight of the electromechanical brake. To further reduce weight, the motor case is preferably formed from aluminum.

[0010] In the cup extrusion molding step, the material intermediate product is formed into the desired shape by cold solid molding between a master mold and a grandfather mold. This eliminates the dropping of chip-like waste during the manufacturing of the motor case. Therefore, the motor case can be manufactured economically. Moreover, since high dimensional and shape accuracy can be obtained with this cup extrusion molding step, post-processing can usually be omitted. By manufacturing the motor case using this step, a large number of units can be produced simultaneously, unlike with machining. Furthermore, this allows for the economical production of such motor cases.

[0011] According to a preferred configuration of the present invention, the motor case is formed by a forward cup extrusion step. In the forward cup extrusion step, the material flow and the matrix movement have the same direction. The advantage of the forward cup extrusion step over the lateral cup extrusion step lies in the preferred structural orientation of the motor case.

[0012] According to a selective configuration of the present invention, the motor case is formed by a retraction cup extrusion step. In the retraction cup extrusion step, the material flow and the matrix movement are in opposite directions. The advantage of the retraction cup extrusion step over the lateral cup extrusion step lies in the favorable microstructure orientation of the motor case.

[0013] In another selective configuration, the motor case is formed by a lateral cup extrusion step. In the lateral cup extrusion step, the material flow is directed laterally, perpendicular to the matrix motion. Such an extrusion step can yield a suitable microstructure orientation for a given application.

[0014] In a preferred embodiment, a seal is provided between the edge of the containment space and the control unit housing. The seal between the control unit housing and the edge of the containment space allows the containment space to be better protected from dirt and moisture.

[0015] In a preferred form, the seal is a wet seal. A wet seal has the advantage that liquid does not accumulate in the seal area in front of the seal, and therefore this seal is more robust against seal intrusion than a solid seal.

[0016] In another preferred embodiment, the seal is an elastic solid seal. The solid seal has the advantage of not requiring surface pretreatment such as laser cleaning or plasma cleaning before the silicon is applied.

[0017] In a preferred embodiment, the edges of the housing space are machined. Such machining can provide, for example, a receiving portion for a seal. Furthermore, the height of the edges can be adapted by machining based on the size of the electric motor used. This means that only one type of motor case is needed to accommodate electric motors of various sizes. This means that only one master mold and one father mold are needed to form various motor cases. Since the manufacture of such master molds and father molds is expensive, motor cases of various sizes can also be manufactured economically.

[0018] In another preferred configuration, the housing space accommodates a parking brake device in addition to the electric motor. Through the parking brake device, the electromechanical brake can be locked in the braked position. This allows the vehicle to be held stationary without current even when the motor is stopped. By placing the parking brake device within the housing space, a separate housing for the parking brake device can be eliminated. This reduces the number of parts required for the mechanical brake.

[0019] The present invention further provides an automobile having such an electromechanical brake. Such an automobile provides the aforementioned advantages and characteristics. [Brief explanation of the drawing]

[0020] [Figure 1]Cross-sectional view of an electromechanical brake according to an embodiment of the present invention. [Figure 2] Cross-sectional view of a motor case according to the present invention.

Mode for Carrying Out the Invention

[0021] Embodiments of the present invention are described in the drawings and explained in detail below.

[0022] FIG. 1 shows a cross-sectional view of an electromechanical brake 10 according to an embodiment of the present invention. The electromechanical brake 10 has an electric motor 18 disposed within a motor case 14. In this case, the motor case 14 is disposed in contact with a brake caliper housing 22 of the electromechanical brake 10. Additionally, the electromechanical brake 10 has a brake plier 26, which grips a brake disk 30 and is disposed in the brake caliper housing 22. The electric motor 18 has a worm 38 disposed on a motor shaft 34, and this worm 38 extends into the brake caliper housing 22 and drives a worm gear 42. The worm gear 42 is attached to a spindle 46 of a spindle drive unit 50 disposed within the brake caliper housing 22. Thereby, the spindle 46 is rotationally driven. The spindle 46 is rotatably supported within the brake caliper housing 22 via a bearing 54. When the spindle 46 rotates, a spindle nut 58 of the spindle drive unit 50 is axially movable.

[0023] In the illustrated embodiment, the spindle drive unit 50 is configured as a ball screw transmission device. A brake controller 66 is disposed on the spindle nut 58, and this brake controller 66 is configured as a brake lining in this embodiment. When the spindle nut 58 moves together with the brake lining 66, the brake lining 66 can contact the brake disk 30 for braking.

[0024] Figure 2 shows a cross-sectional view of a motor case 14 according to the present invention. The motor case 14, made of a metal material, forms a bowl-shaped housing space 70, in which an electric motor 18 is housed. The motor case 14 is manufactured by a cup extrusion molding step. This manufacturing step significantly reduces the amount of waste material in the form of chips compared to machining the motor case 14. Since one axial end of the motor case 14 is open, the electric motor 18 can be assembled through this open axial end. In the illustrated embodiment, in addition to the electric motor 18, a parking brake device 74 is also located in the housing space 70. This eliminates the need for a separate case for the parking brake device 74.

[0025] The open axial end of the motor case 14 is closed by a control unit housing 78, within which a control unit 82 for controlling the electric motor 18 is located. This eliminates the need for a separate lid to close the motor case 14. Additionally, wiring costs between the electric motor 18 and the control unit 82, and between the control unit 82 and the parking brake device 74, can be reduced. To prevent dirt and moisture from entering the housing space 70, a seal 86 is placed between the control unit housing 78 and the motor case 14. In this case, the seal 86 is located in a groove 94 formed by the edge 90 of the motor case 14. [Explanation of symbols]

[0026] 10 Brake 14 Motor Case 18 Electric motor 22 Brake caliper housing 26 Brake pliers 30 Brake Discs 34 Motor shaft 38 Warm 42 Worm gear 46 spindles 50 Spindle drive unit 54 Bearings 58 Spindle nut 62 Axis 66 Brake controller, brake lining 70 storage spaces 74 Parking brake device 78 Control Unit Housing 82 Control Unit 86 Seals 90 Edge 94 Groove

Claims

1. An electromechanical brake (10) for an automobile, having an electric motor (18), the electric motor (18) rotationally drives a spindle drive unit (50) located in a brake caliper housing (22), thereby allowing a brake controller (66) to slide axially (62) in the brake caliper housing (22) to apply braking force, a motor case (14) located in the brake caliper housing (22) receiving the electric motor (18), and a control unit housing (78) for a control unit (82) that controls the electric motor (18) located in the motor case (14), An electromechanical brake (10) for an automobile, characterized in that the motor case (14) is formed from a metal material, the metal material forms a bowl-shaped housing space (70), the electric motor (18) is housed in the housing space (70), the motor case (14) is closed via the control unit housing (78), and the motor case (14) is formed by a cup extrusion molding step.

2. The electromechanical brake (10) according to claim 1, characterized in that the motor case (14) is formed by a forward cup extrusion molding step.

3. The electromechanical brake (10) according to claim 1, characterized in that the motor case (14) is formed by a retractable cup extrusion molding step.

4. The electromechanical brake (10) according to claim 1, characterized in that the motor case (14) is formed by a lateral cup extrusion molding step.

5. An electromechanical brake (10) according to any one of claims 1 to 4, characterized in that a seal (86) is disposed between the edge (90) of the housing space (70) and the control unit housing (78).

6. The electromechanical brake (10) according to claim 5, characterized in that the seal (86) is a wet seal.

7. The electromechanical brake (10) according to claim 5, characterized in that the seal (86) is an elastic solid seal.

8. The electromechanical brake (10) according to any one of claims 5 to 7, characterized in that the edge (90) of the storage space (70) is machined.

9. The electromechanical brake (10) according to any one of claims 1 to 8, characterized in that the aforementioned storage space (70) further accommodates a parking brake device (74) in addition to the electric motor (18).

10. An automobile having an electromechanical brake (10) according to any one of claims 1 to 9.

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