Actuating device for brake system, brake system

Abstract

The invention relates to an actuating device (1) for a brake system (2), comprising a housing (3), a pressure element (27) which is movably mounted in the housing (3), and an electric motor (29) which is operatively connected to the pressure element (27) by means of a transmission (33) such that the pressure element (27) can be moved by means of the electric motor (29). According to the invention, the housing (3) is an extruded profile (3) having at least two cylindrical housing sections (5, 6) arranged parallel to one another, and the pressure element (27) is arranged at least partially in a first housing section (5) of the housing sections (5, 6) and the electric motor (29) is arranged at least partially in a second housing section (6) of the housing sections (5, 6).

Description

Technical Field

[0001] The invention relates to an actuating device for a brake system, comprising a housing, a pressure element movably supported in the housing, and an electric motor which is operatively connected to the pressure element via a transmission so that the pressure element can be moved by the electric motor.

[0002] The invention also relates to a braking system. Background Art

[0003] The braking system of a motor vehicle usually has a plurality of friction brake devices. The friction brake device is effectively connected to an operating device so that the friction brake device can be operated by the operating device. As the degree of electrification of motor vehicles continues to increase, the operating devices of the brake system are also increasingly electrified. An operating device of the type mentioned at the beginning is known, for example, from the patent publication DE 10 2019 203 511 A1. The operating device has a housing in which a pressure element is movably supported. In addition, the operating device has an electric motor, which is effectively connected to the pressure element via a transmission device so that the pressure element can be moved by the electric motor. In the operating device known from the patent publication DE 10 2019 203 511 A1, the pressure element and the electric motor are arranged in different housings that are manufactured independently of each other. Summary of the invention

[0004] The advantage of the operating device according to the invention with the features of claim 1 is that the vibrations of the motor are reduced. To this end, it is provided according to the invention that the housing is an extruded profile having at least two cylindrical housing sections arranged parallel to one another, and the pressure element is at least partially arranged in a first of the housing sections, and the motor is at least partially arranged in a second of the housing sections. Instead of the housings mentioned above, which are manufactured independently of one another, a single housing, i.e. an extruded profile, having two housing sections is used. Since the motor is not arranged in a separate housing, the rigidity of the connection to the motor is increased. This reduces the vibrations of the motor during operation of the operating device. In addition, the number of individual parts is reduced, thereby reducing the manufacturing costs and / or assembly costs of the operating device. Since the manufacture of extruded profiles is generally relatively inexpensive, the manufacturing costs are further reduced. According to the invention, the housing sections are cylindrically constructed. The cylindrically constructed element has a side wall, which has a contour that is at least substantially closed in the circumferential direction. Preferably, the first side wall forming the first housing section and / or the second side wall forming the second housing section are closed in the circumferential direction. However, the term "cylindrical" does not mean a cross-section with a specific shape. On the contrary, the cross-section of the housing segments can have different shapes. However, the second housing segment preferably has a circular cross-section. A circular cross-section is particularly suitable for accommodating an electric motor. According to the invention, the housing segments are arranged parallel to each other. Therefore, the housing segments are arranged radially offset from each other relative to an axis oriented perpendicular to the cross-section of the extruded profile. The shape of the cross-section of the extruded profile corresponds to the opening of the extrusion tool used to produce the extruded profile. Preferably, the extruded profile has a cross-section in the shape of an Arabic numeral "8".

[0005] The extruded profile is preferably made of aluminum. By making the extruded profile from aluminum, the production costs of the extruded profile are further reduced. In addition, since the extruded profile is made of aluminum, its mass is very low. Preferably, the extruded profile has a wall thickness of 1.5 mm to 3 mm. Such a wall thickness can be produced cost-effectively on the one hand and provides sufficient mechanical strength on the other hand. A wall thickness of 2 mm is particularly preferred.

[0006] According to a preferred embodiment, the first housing section and the second housing section are partially formed by a common side wall. Thus, the first side wall forming the first housing section and the second side wall forming the second housing section are partially identical. As a result, the connection of the two housing sections to each other has a high rigidity, which will reduce vibrations of the motor particularly effectively during operation of the operating device. According to another embodiment, the extruded profile is preferably designed so that the housing sections are spaced apart from each other and are connected to each other by connecting pieces or the like.

[0007] According to a preferred embodiment, the transmission has a planetary gear mechanism, which is at least partially arranged in the second housing section. The planetary gear mechanism can realize a transmission stage with a high transmission ratio. This allows the electric machine to be designed to be very small and thus save space. In addition, by using a planetary gear mechanism, the rotational speed of a further transmission stage connected downstream of the planetary gear mechanism can be reduced due to the high transmission ratio, thereby reducing the noise emission of the actuating device.

[0008] According to a preferred embodiment, the planetary gear mechanism has a ring gear fixed relative to the housing, and the radially outwardly directed side of the ring gear has at least one radial projection, which radially engages in a radial projection of the second housing section to form a rotation stop that acts between the second housing section and the ring gear. The ring gear is arranged in a fixed manner relative to the housing so that during operation of the actuating device, the torque generated by the electric motor is transmitted to the second housing section via the ring gear. By means of the aforementioned rotation stop, it is achieved that even high torques can be reliably transmitted from the ring gear to the second housing section. Since the second housing section is part of an extruded profile, the radial projection is technically easy to produce, for example in the form of a groove that extends axially through the second side wall forming the second housing section.

[0009] Preferably, the operating device has a sleeve-shaped first housing extension, which is arranged at the first end side of the extruded profile and cooperates with the extruded profile to form a fluid seal. The end side of the extruded profile is the front side and rear side of the extruded profile relative to the axis oriented perpendicular to the cross section of the extruded profile. Through the sleeve-shaped first housing extension, the housing volume of the first housing section and / or the housing volume of the second housing section are extended in the axial direction beyond the first end side of the extruded profile. In addition, it is easier to fix other elements at the extruded profile, wherein the first housing extension acts as an adapter. Preferably, the first housing extension is arranged at the first end side of the extruded profile only in the area of ​​the first housing section. Accordingly, only the housing volume of the first housing section is extended by the first housing extension, and the first housing extension only cooperates with the extruded profile in the area of ​​the first housing section to form a fluid seal. In the area of ​​the second housing section, the first end side of the extruded profile does not have the first housing extension. Preferably, in the area of ​​the second housing section, a controller is arranged at the first end side of the extruded profile, which is configured to control the motor. Preferably, the end section of the first housing extension, which is associated with the extruded profile, extends into the first housing section and radially abuts from the inside against a first side wall forming the first housing section to form a fluid seal. Preferably, the first housing extension is made of plastic, particularly preferably by injection molding. Even complex structures can be produced cost-effectively by injection molding.

[0010] Preferably, the operating device has a sleeve-shaped second housing extension, which is arranged at the second end side of the extruded profile facing away from the first end side and cooperates with the extruded profile to form a fluid seal. Preferably, the second housing extension is arranged at the second end side of the extruded profile in the region of the first housing section and in the region of the second housing section. Therefore, the second housing extension extends the first housing section and the second housing section in the axial direction. In addition, it is easier to fix other elements at the extruded profile, wherein the second housing extension serves as an adapter. Preferably, the transmission device is at least partially arranged in the second housing extension. As an example, the planetary gear carrier of the aforementioned planetary gear transmission extends from the second housing section and extends into the second housing extension. Preferably, the end section of the second housing extension assigned to the extruded profile radially surrounds the extruded profile to form a fluid seal. Preferably, the second housing extension is made of plastic, particularly preferably made by injection molding.

[0011] According to a preferred embodiment, the actuating device has a master brake cylinder fixed relative to the housing, which has at least one movably mounted hydraulic piston, wherein the master brake cylinder is arranged at a first end side of the extruded profile or at an end side of the first housing extension facing away from the first end side of the extruded profile, and wherein the pressure element is operatively connected to the hydraulic piston so that the hydraulic piston can be moved by the pressure element. If the first housing extension is present and the master brake cylinder is arranged at the end side of the first housing extension, the first housing extension forms a kind of adapter for fastening the master brake cylinder to the extruded profile. The first housing extension makes it easier to connect the master brake cylinder to the extruded profile.

[0012] Preferably, the actuating device has a housing plate which is arranged at the second end side of the extruded profile or at the end side of the second housing extension facing away from the second end side of the extruded profile. Preferably, an end section of the second housing extension associated with the housing plate radially surrounds the housing plate to form a fluid seal acting between the housing plate and the second housing extension.

[0013] Preferably, the master brake cylinder and the housing plate are fastened to the extruded profile by means of different fastening elements. As an example, the master brake cylinder is fastened to the extruded profile by means of at least one first fastening element, and the housing plate is fastened by means of at least one second fastening element. Since the master brake cylinder and the housing plate are fastened to the extruded profile by means of different fastening elements, the arrangement of the fastening elements can be optimized independently of one another.

[0014] According to a preferred embodiment, it is provided that the first fastening element assigned to the master brake cylinder is arranged radially inside the second fastening element assigned to the housing plate relative to the longitudinal center axis of the pressure element. As already mentioned, the use of different fastening elements offers the advantage that the arrangement of the fastening elements can be optimized independently of one another. Since the first fastening element is arranged radially inside the second fastening element, the dimensions of the mounting flange of the master brake cylinder, with which the first fastening element cooperates for fastening the master brake cylinder to the extruded profile, can be reduced. This reduces the installation space required for the master brake cylinder and the weight of the master brake cylinder.

[0015] According to a preferred embodiment, the fixing element engages axially in the axial penetration of the extruded profile. This makes it possible to fix the master brake cylinder or the housing plate to the extruded profile in a mechanically stable manner. In addition, the axial penetration is technically very easy to produce by extrusion. As an example, the fixing element is designed as a screw and is screwed into the axial penetration. Alternatively, the fixing element is pressed into the axial penetration for this purpose, for example.

[0016] The brake system according to the invention having the features of claim 13 is characterized by an actuating device according to the invention. The brake system also yields the advantages already mentioned. Further preferred features and feature combinations are given by the above description and the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be explained in more detail below with reference to the accompanying drawings. The accompanying drawings show:

[0018] Figure 1 is a perspective view of an operating device for a brake system;

[0019] Figure 2 is the housing of the control device;

[0020] Figure 3 is a cross-sectional view of the control device; and

[0021] Figure 4 is another cross-sectional view of the operating device. DETAILED DESCRIPTION

[0022] Figures 1 to 4 An actuating device 1 for a brake system 2 of a motor vehicle, not shown in detail, is shown. The actuating device 1 has a housing 3 which is designed as an extruded profile 3. Figure 2 The structure of the extruded profile 3 is explained in more detail. Figure 2 A perspective view of an extruded profile 3 is shown.

[0023] The extruded profile 3 has a first shell section 5 and a second shell section 6. The first shell section 5 is formed by a surrounding first side wall 7. The second shell section 6 is formed by a surrounding second side wall 8. In this respect, the shell sections 5 and 6 are cylindrically constructed. In the present case, the extruded profile 3 is constructed so that the first shell section 5 and the second shell section 6 are formed by a common side wall in the section 9. In the section 9, the first side wall 7 coincides with the second side wall 8. The shell sections 5 and 6 are arranged parallel to each other. This means that the shell sections 5 and 6 are arranged in a radially staggered manner relative to an axis oriented perpendicularly to the cross section of the extruded profile 3. Preferably, the extruded profile 3 is made of aluminum. In the present case, the second shell section 6 has a circular cross section. In the present case, the first shell section 5 has an irregularly shaped cross section. However, the shell sections 5 and 6 may also have cross sections that are different from those shown in the figure. As an example, according to another embodiment, the first shell section 5 has a circular cross section.

[0024] The operating device 1 also has a sleeve-shaped first housing extension 10. The first housing extension 10 is made of plastic, preferably by injection molding. In the area of ​​the first housing section 5, the first housing extension 10 is arranged at the first end side 11 of the extruded profile 3. In the area of ​​the second housing section 6, the first end side 11 of the extruded profile 3 does not have the first housing extension 10. Through the first housing extension 10, the housing volume of the first housing section 5 is extended beyond the first end side 11 of the extruded profile 3. The first housing extension 10 works together with the extruded profile 3 to form a fluid seal in the area of ​​the first end side 11. In the present case, the end section 12 of the first housing extension 10 assigned to the extruded profile 3 extends into the first housing section 5 and radially abuts the first side wall 7 from the inside to form a fluid seal.

[0025] The actuating device 1 further comprises a sleeve-shaped second housing extension 13. The second housing extension 13 is made of plastic, preferably by injection molding. In the region of the first housing section 5 and in the region of the second housing section 6, the second housing extension 13 is arranged at the second end side 14 of the extruded profile 3 facing away from the first end side 11. By means of the second housing extension 13, the housing volume of the first housing section 5 and the housing volume of the second housing section 6 are extended beyond the second end side 14. The second housing extension 13 here cooperates with the extruded profile 3 to form a fluid seal in the region of the second end side 14. In the present case, the end section 15 of the second housing extension 13 assigned to the extruded profile 3 radially surrounds the extruded profile 3 to form a fluid seal.

[0026] The actuating device 1 further comprises a housing plate 16. The housing plate 16 is arranged at the end side 19 of the second housing extension 13 facing away from the extruded profile 3. The second housing extension 13 cooperates with the housing plate 16 to form a fluid seal. In the present case, an end section 18 of the second housing extension 13 assigned to the housing plate 16 radially surrounds the housing plate 16 to form a fluid seal.

[0027] The actuating device 1 further comprises a master brake cylinder 20. The master brake cylinder 20 is arranged at the end side 75 of the first housing extension 10 facing away from the first end side 11. A first hydraulic piston 21 and a second hydraulic piston 22 are supported in the master brake cylinder 20 so as to be movable, i.e., movable in a first direction 23 and in a second direction 24 opposite to the first direction 23. The master brake cylinder 20 comprises a plurality of hydraulic couplings 25, 26. If the actuating device 1 is installed in the brake system 2 as specified, the hydraulic couplings 25, 26 are fluidically connected to the slave cylinders of the friction brake device of the brake system 2. The friction brake device can then be actuated by moving the hydraulic pistons 25, 26 in the first direction 23.

[0028] The actuating device 1 further comprises a movably mounted pressure element 27 or actuating element 27, which in the present case is designed as a push rod 27. The pressure element 27 can also be moved in the first direction 23 and in the second direction 24. Figure 3 and Figure 4 It can be seen that the pressure element 27 is at least partially arranged in the first housing section 5. It is assumed here that the pressure element 27 is at least partially arranged in the first housing section 5, even if the pressure element 27 protrudes axially from the first housing section 5. The pressure element 27 is coupled to the hydraulic pistons 21, 22, so that the hydraulic pistons 21, 22 can be moved in the first direction 23 by the pressure element 27. Therefore, the friction brake device can be actuated by moving the pressure element 27.

[0029] The operating device 1 also has a drive unit 28 with an electric motor 29. Figure 4 It can be seen that the electric motor 29 is arranged in the housing 3, namely in the second housing section 6. In the present case, the stator 30 of the electric motor 28 is pressed into the second housing section 6. The electric motor 29 also has a rotor 31, which is arranged in a rotationally fixed manner on a motor shaft 32, which is rotatably supported in the second housing section 6.

[0030] The electric motor 29 is operatively connected to the pressure element 27 via a transmission 33, so that the pressure element 27 can be moved by the electric motor 29. Accordingly, the friction brake device of the brake system 2 can be actuated by the electric motor 29.

[0031] The transmission 33 has a planetary gear mechanism 34. The planetary gear mechanism 34 has a toothed ring 35 fixed relative to the housing. The toothed ring 35 is arranged in the second housing section 6. The toothed ring 35 has a sleeve-shaped fixing section 36. The radially inwardly directed side 37 of the fixing section 36 has an internal toothing 38. The radially outwardly directed side 39 of the fixing section 36 radially abuts against the second side wall 8 forming the second housing section 6 from the inside. Figure 2 It can be seen that the second housing section 6 has a plurality of radial projections 40. The radially outwardly directed side surface 39 of the fixing section 36 has a number of radial projections corresponding to the number of radial projections 40, which radially engage in the radial projections 40 to form a rotational stop acting between the second housing section 6 and the ring gear 35.

[0032] The ring gear 35 also has a sleeve-shaped bearing section 41. The bearing section 41 radially surrounds the motor shaft 32, thereby forming a sliding bearing 42 for the motor shaft 32. Therefore, the motor shaft 32 is rotatably supported on the side of the rotor 31 facing the ring gear 35 via the bearing section 41 of the ring gear 35.

[0033] The motor shaft 32 is supported on the side of the rotor 31 facing away from the ring gear 35 by a bearing cover 4 fixed relative to the housing. The bearing cover 4 carries a roller bearing 43, which acts between the bearing cover 4 and the motor shaft 32. The drive unit 28 also has a sensor (not shown in the figure) that is configured to detect the rotation state of the rotor 31 and thus the rotation state of the motor shaft 32 on the side of the rotor 31 facing away from the ring gear 35. As an example, the sensor is arranged between the rotor 31 and the bearing cover 4.

[0034] The ring gear 35 also has a circular disk section 70, which is arranged at the end of the fixing section 36 facing the rotor 31. The conical section 45 of the ring gear 35 is arranged at the radially inner end 44 of the circular disk section 70. The conical section 45 tapers in the direction of the rotor 31. The bearing section 41 of the ring gear 35 is arranged at the end of the conical section 45 facing the rotor 31.

[0035] The planetary gear 34 further comprises a sun gear 46. The sun gear 46 is arranged on the side of the bearing section 41 facing away from the rotor 31 in a rotationally fixed manner on the motor shaft 32. The bearing section 41 supports the motor shaft 32 between the sun gear 46 and the rotor 31.

[0036] The planetary gear mechanism 34 also has a rotatably supported planetary gear carrier 47. The planetary gear carrier 47 has a carrier section 48. A plurality of planetary gears 49 are rotatably supported at the carrier section 48 and engage with the internal gear 38 on the one hand and engage with the sun gear 46 on the other hand. The planetary gear carrier 47 also has an output shaft 50. A gear 51 is arranged on the output shaft 50 in a non-rotatable manner. On the side of the gear 51 facing the motor 29, the output shaft 50 is rotatably supported by another bearing cover 52 fixed to the housing. In the present case, the other bearing cover 52 is arranged at the second housing extension 13. The other bearing cover 52 carries a roller bearing 53, which acts between the output shaft 50 and the other bearing cover 52. On the side of the gear 51 facing away from the motor 29, the output shaft 50 is supported by the housing plate 16. For this purpose, the housing plate 16 carries a roller bearing 54, which acts between the output shaft 50 and the housing plate 16.

[0037] The transmission 33 also has a spindle drive 55, which has a rotatably mounted spindle nut 56 and a movable threaded spindle 57. The spindle drive 55 is arranged in a penetration 58 of the housing plate 16. A toothed ring 59, which is arranged in a rotationally fixed manner on the spindle nut 56, meshes with the gear 51, so that the spindle drive 55 can be driven by the planetary gear 34, more precisely by the motor shaft 32. Therefore, the rotation of the motor shaft 32 can be converted into a translational movement of the threaded spindle 57 by the transmission 33. The threaded spindle 57 is coupled to the pressure element 27, so that the pressure element 27 can be moved by the threaded spindle 57.

[0038] The operating device 1 further comprises an operating element 60, which is movably supported in an axial penetration 61 of the threaded spindle 57. A first end 62 of the operating element 60 can be connected to or with a brake pedal of the brake system 2 via an input rod 63, so that the operating element 60 can be moved by operating the brake pedal. A second end 64 of the operating element 60 is connected to the pressure element 27, so that the pressure element 27 can be moved by the operating element 60. Therefore, the friction brake device can also be directly operated by operating the brake pedal.

[0039] The master brake cylinder 20 is fixed to the extruded profile 3 by a plurality of first fixing members 65. For this purpose, the extruded profile 3 has a plurality of first axial penetrations 66. The first fixing members 65 are configured as screw members 65 and are screwed into the first axial penetrations 66 to fix the master brake cylinder 20 to the extruded profile 3. In order to eliminate the axial distance between the extruded profile 3 and the master brake cylinder 20, the actuating device 1 has a number of sleeves 67 corresponding to the number of the first fixing members 65, which are axially arranged between the master brake cylinder 20 and the extruded profile 3. The first fixing members 65 pass through different sleeves 67, respectively.

[0040] The housing plate 16 is fixed to the extruded profile 3 by a plurality of second fixing members 68. To this end, the extruded profile 3 has a number of second axial penetrations 69 corresponding to the number of the second fixing members 68. The second fixing members 68 are configured as screw members 68 and are screwed into the second axial penetrations 69 of the extruded profile 3 to fix the housing plate 16 to the extruded profile 3.

[0041] from Figure 3 It can be seen that the first fixing part 65 and the first axial penetration 66 are arranged radially inside the second fixing part 68 and the second axial penetration 69 relative to the longitudinal center axis 71 of the pressure element 27. This has the advantage that the size of the mounting flange 72 of the master brake cylinder 20 in the radial direction can be reduced.

Claims

1. An operating device for a brake system, the operating device comprising a housing (3), a pressure element (27) movably supported in the housing (3), and an electric motor (29), the electric motor being operatively connected to the pressure element (27) via a transmission (33) so that the pressure element (27) can be moved by the electric motor (29), characterized in that: The housing (3) is an extruded profile (3) having at least two cylindrical housing sections (5, 6) arranged parallel to one another, and the pressure element (27) is at least partially arranged in a first housing section (5) of the housing sections (5, 6) and the motor (29) is at least partially arranged in a second housing section (6) of the housing sections (5, 6).

2. The operating device according to claim 1, characterized in that The extruded profile (3) is made of aluminum.

3. An operating device according to any one of the preceding claims, characterized in that The first housing section (5) and the second housing section (6) are formed in regions by a common side wall.

4. An operating device according to any one of the preceding claims, characterized in that The transmission (33) has a planetary gear (34) which is arranged at least partially in the second housing section (6).

5. An operating device according to any one of the preceding claims, characterized in that The planetary gear mechanism (34) has a ring gear (35) fixed relative to the housing, and the radially outwardly pointing side surface (39) of the ring gear (35) has at least one radial protrusion, which radially engages in a radial protrusion (40) of the second housing section (6) to form a rotation stop that acts between the second housing section (6) and the ring gear (35).

6. An operating device according to any one of the preceding claims, characterized in that The actuating device has a first sleeve-shaped housing extension (10), which is arranged on a first end side (11) of the extruded profile (3) and cooperates with the extruded profile (3) to form a fluid-tight seal.

7. An operating device according to any one of the preceding claims, characterized in that The actuating device has a sleeve-shaped second housing extension (13), which is arranged on a second end side (14) of the extruded profile (3) facing away from the first end side (11) and cooperates with the extruded profile (3) to form a fluid-tight seal.

8. An operating device according to any one of the preceding claims, characterized in that The actuating device comprises a master brake cylinder (20) fixed relative to a housing, the master brake cylinder having at least one movably supported hydraulic piston (21, 22), wherein the master brake cylinder (20) is arranged at a first end side (11) of the extruded profile (3) or at an end side (75) of the first housing extension (10) facing away from the first end side (11) of the extruded profile (3), and wherein the pressure element (27) is operatively connected to the hydraulic piston (21, 22) so that the hydraulic piston (21, 22) can be moved by the pressure element (27).

9. An operating device according to any one of the preceding claims, characterized in that The actuating device has a housing plate (16) which is arranged on a second end side (14) of the extruded profile (3) or on an end side (19) of the second housing extension (13) facing away from the second end side (14) of the extruded profile.

10. The operating device according to any one of claims 8 and 9, characterized in that The master brake cylinder (20) and the housing plate (16) are fastened to the extruded profile (3) via different fastening elements (65, 68).

11. The operating device according to claim 10, characterized in that A first fastening element (65) associated with the master brake cylinder (20) is arranged radially inwardly of a second fastening element (68) associated with the housing plate (16) relative to a longitudinal center axis (71) of the pressure element (27).

12. The operating device according to any one of claims 10 and 11, characterized in that The fixing elements (65, 68) engage axially in axial penetrations (66, 69) of the extruded profile (3).

13. Braking system having an actuating device (1) according to any one of the preceding claims.

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