DRIVE INCLUDING AN ELECTRIC MOTOR WITH A BRAKE ASSEMBLY

Abstract

A drive includes an electric motor with a brake assembly. The electric motor has a rotor rotatably mounted via a first bearing and a second bearing and has a housing part. The first bearing has an inner ring and an outer ring, and the inner ring is received on the rotor, e.g., placed thereover, e.g., is positioned against a step or pressed against a catch that is positioned against a step formed on the rotor. The brake assembly has a magnetic body, e.g., made of a ferromagnetic material. The outer ring is received in the magnetic body of the brake assembly, e.g., is positioned against a step.

Claims

1-15. (canceled)

16. A drive, comprising: an electric motor including a rotor, rotatably mounted via a first bearing and a second bearing, and a housing part, the first bearing including an inner ring and an outer ring, the inner ring being arranged on the rotor; and a brake assembly including a magnetic body, the outer ring being arranged in the magnetic body.

17. The drive according to claim 16, wherein the inner ring is arranged against a step and/or pressed against a catch arranged against a step on the rotor, the magnetic body is formed of a ferromagnetic material, and the outer ring is arranged against a step.

18. The drive according to claim 16, wherein the second bearing and/or an outer ring of the second bearing is arranged in the housing part or in a flange part connected to the housing part and/or is arranged against a step, and an inner ring of the second bearing is arranged on the rotor and/or is arranged against a step.

19. The drive according to claim 16, wherein the magnetic body is arranged in a receiving part connected securely to the housing part or is arranged in the housing part, the magnetic body is arranged displaceable axially and is connected to a first torque support part, the first torque support part is connected to the receiving part and/or to the housing part.

20. The drive according to claim 19, wherein the magnetic body is arranged displaceable axially parallel to a direction of a rotational axis of the rotor, the magnetic body is connected to the first torque support part by second screws and/or by second screws spaced apart from one another regularly in a circumferential direction, and the first torque part is connected to the receiving part and/or to the housing part by first screws and/or first screws spaced apart from one another regularly in the circumferential direction.

21. The drive according to claim 19, wherein (a) the first torque support part is arranged as a bellows and/or a metal bellows, a region of the first torque support part contacting the receiving part is spaced apart axially from a region contacting the magnetic body and/or a region that is arranged at a smaller radial distance than the region contacting the receiving part, and/or (b) the first torque support part is arranged as a sheet part and/or a sheet metal part such that a region of the first torque support part contacting the receiving part is arranged at a same axial position as a region of the torque support part contacted by the magnetic body and/or that is arranged at a smaller radial distance than the region contacting the receiving part.

22. The drive according to claim 16, wherein an armature disk, with a catch, is arranged rotationally-fixed and axially displaceable.

23. The drive according to claim 22, wherein a spring element arranged between the catch and the armature disk and/or a spring plate connected to the catch by first connecting elements and/or rivets and connected to the armature disk by second connecting elements and/or rivets is adapted to generate a spring force oriented towards the catch and acting on the armature disk.

23. The drive according to claim 16, wherein (a) a coil is arranged in the magnetic body and/or arranged in a radial direction between an inner ring of the magnetic body and an outer ring of the magnetic body, and/or (b) a permanent magnet is arranged between the inner ring of the magnetic body and the outer ring of the magnetic body and/or is arranged in an axial direction between the inner ring of the magnetic body and the outer ring of the magnetic body.

24. The drive according to claim 16, wherein the outer ring of the first bearing is positioned against a step arranged on the magnetic body and/or on an inner ring of the magnetic body, and the inner ring of the first bearing is arranged against a step formed on a shaft.

25. The drive according to claim 23, wherein when the coil is energized, magnetic flux penetrating an armature disk is reduced and/or reduced in comparison to when the coil is not energized.

26. The drive according to claim 19, wherein an outer ring of the magnetic body is arranged displaceable axially in the receiving part.

27. The drive according to claim 16, wherein a rotor shaft of an angle sensor is connected rotationally-fixed to the rotor, and a housing of the angle sensor is connected to a first region of a torque support part, a second region of the torque support part being connected to an inner ring of the magnetic body.

28. The drive according to claim 27, wherein the second region is arranged at a greater radial distance than the first region and/or the second region is arranged radially further outward than the first region.

29. The drive according to claim 16, wherein a radial distance region covered by a first torque support part is spaced apart from a radial distance region covered by a second torque support part.

30. The drive according to claim 19, wherein the first torque support part includes an inner ring region, an outer ring region, and crosspieces that connect the inner ring region to the outer ring region and that are spaced apart from one another regularly in a circumferential direction, the inner ring region is arranged against an inner ring of the magnetic body and the outer ring region is arranged against the receiving part or the housing part, and a greatest circumferential angle value of a circumferential angle region covered by a specific crosspiece at a radial distance increases or decreases monotonically as radial distance increases, and a smallest circumferential angle value of the circumferential angle region increases or decreases monotonically as radial distance increases.

31. The drive according to claim 21, wherein the bellows is supported on the receiving part presses an inner ring of the magnetic body and/or a step arranged on the inner ring of the magnetic body toward the outer ring of the first bearing such that the inner ring of the first bearing presses a catch against a step formed on the rotor, and/or a spring element supported on the receiving part, the housing part, or a ring securely connected to the receiving part or the housing part presses an inner ring of the magnetic body and/or a step formed on the inner ring of the magnetic body toward the outer ring of the first bearing such that the inner ring of the first bearing presses the catch against the step formed on the rotor.

32. The drive according to claim 18, wherein an outer ring of the second bearing is arranged in an insulating part and/or an insulating part formed of fiberglass-reinforced plastic that is arranged in the housing part, and the flange part is arranged on a side of the insulating part facing away from the first bearing.

33. The drive according to claim 32, wherein the outer ring of the second bearing is arranged in the insulating part when the flange part and a gearbox have not yet been connected to the housing part, and the insulating part is arranged in a circumferential groove of the housing part.

34. The drive according to claim 33, wherein a first subregion of a region covered axially by an outer ring of the second bearing in an axial direction contacts the flange part and a second subregion of the region covered axially by the outer ring of the second bearing contacts the insulating part, the first subregion being spaced apart from or being adjacent to the second subregion.

35. The drive according to claim 34, wherein the first subregion does not overlap with the second subregion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG. 1 is a cross-sectional view of a inventive drive having a gearbox driven by a brake motor, in which a bellows 40 arranged as torque support is provided for producing bearing tension of the bearing arrangement of the rotor 9 of the brake motor.

[0041] FIG. 2 is a cross-sectional view of a drive, in which a first torque support part 10 of the brake assembly is provided instead of the bellows 40.

[0042] FIG. 3 is a top view of the torque support part

[0043] FIG. 4 is an enlarged view of a portion of FIG. 1.

DETAILED DESCRIPTION

[0044] As illustrated in FIG. 2 and FIG. 3, the electric motor includes a rotor 9 that is mounted axially bilaterally by fixed bearings and that at its first axial end region is connected rotation-fast to a rotor shaft of an angle sensor 15.

[0045] At its end region facing away from the angle sensor 15, the rotor 9 is connected rotationally-fixed to a sun gear of a planetary gear stage of the gearbox. The sun gear is, e.g., connected to the rotor 9 as a plug-in pinion.

[0046] Planetary gears that are rotatably mounted on a planetary carrier and that are engaged with a ring gear connected to the gearbox housing are engaged with the sun gear. The planetary carrier is arranged as output shaft of the planetary gear stage. The gearbox housing is connected to a flange part 22 receiving the bearing 24 of the rotor 9. This bearing 22 is arranged as a fixed bearing. To this end, the flange part 22 has a step against which the outer ring of the bearing 22 is arranged. The inner space of the bearing 22 is positioned against a step arranged on the rotor 9.

[0047] The region covered axially by the bearing 24, that is, parallel to the rotational axis of the rotor 9, overlaps with the sun gear arranged as a plug-in pinion and/or the region covered axially by the flange part 22, that is parallel to the rotational axis of the rotor 9, overlaps with the sun gear arranged as a plug-in pinion.

[0048] In addition, an insulating part 23 for thermal and electric separation and for receiving the bearing is received in the housing part 1 for functional testing. To this end, an inner groove is added to the housing part 1 and the insulating part 23 is inserted into the inner groove. This insulating part 23 also receives the outer ring of the bearing 24. However, the insulating part 23 does not have a step, so that the bearing 24 is not axially limited by the insulating part 23.

[0049] The insulating part 23 is, for example, made of a fiberglass-reinforced plastic and thus has enough stability for carrying out a functional test of the electric motor when the gearbox, and thus also the flange part 22, are not present. However, only idling of the electric motor is possible for the functional testing.

[0050] The inner ring of the bearing 24 is seated on a finely machined bearing seat on the rotor 9 and is positioned against the step of the rotor 9. The outer ring of the bearing 24 is inserted into a recess of the insulating part 23 and is not secured axially as long as the outer ring is not received in the flange part 22 and positioned against the step thereof.

[0051] Thus, during production merely functional testing is possible while the electric motor is idling, but testing under load is not possible.

[0052] Since the bearing 9 is arranged very near the sun gear connected to the rotor 9, thermal expansion of the rotor 9 and/or housing 1 does not cause a significant change in the angle on the sun gear and the planetary gears engaged therewith.

[0053] The first bearing 8 of the rotor 9 is also arranged as a fixed bearing. Both the inner ring of the first bearing 8 and the outer ring of the bearing 8 are axially limited. To this end, a step is, for example, formed on the rotor 9, and the inner ring of the first bearing 8 is arranged axially adjacent to a catch 7 that is positioned against a step of the rotor 9.

[0054] The outer ring of the first bearing 8 is received in an inner ring 13 of a magnetic body of the brake assembly arranged on the electric motor and is positioned against a step of the inner ring 13 of the magnetic body.

[0055] The magnetic body is formed from the inner ring 13 and an outer ring 3. A coil 6 to which current can be applied via electrical supply lines 18 is placed over the inner ring 13 of the magnetic body so that the coil 6 can be energized.

[0056] The coil 6 is arranged radially within the outer ring 3 of the magnetic body and radially outside of the inner ring 8 of the magnetic body.

[0057] A receiving part 2, e.g., a brake bearing shield, is attached to the housing part 1. The magnetic body, with the coil 6 contained therein, is received in the receiving part 2.

[0058] For pretensioning the bearing arrangement formed from the first bearing 8 and the second bearing 9, spring elements 12 supported on a ring 11 connected to the receiving part 2 press the inner ring 13 of the magnetic body towards the outer ring of the first bearing 8 and thus in the direction of the second bearing 24.

[0059] Thus, the spring elements 12 prestress the bearing arrangement. That is, if the housing 1 experiences stronger thermally-caused expansion than the rotor 9, the bearing arrangement remains prestressed. Although the rotor 9 is mounted in two fixed bearings, the bearing arrangement is protected from stresses that are too high.

[0060] In addition, the functioning of the brake is unaffected.

[0061] This is because arranged between the outer ring 3 of the magnetic body and the inner ring 13 of the magnetic body is a permanent magnet 14, the magnetic flux of which is guided through the outer ring 3 to an armature disk 4 and from the armature disk 4 to the inner ring 13 of the magnetic body.

[0062] A spring plate arranged axially between the armature disk 4 and the catch 7 is attached to the armature disk 4 with first connecting elements 5, e.g., rivets. The spring plate is attached to the catch 7 with two connecting elements, e.g., rivets. The spring plate resists distancing of the armature disk 4 from the catch 7. This is because as the distance of the armature disk 4 from the catch 7 increases, the spring force pulls the armature disk 4 back, that is, towards the catch 7, with increasing force. The magnetic force of the permanent magnet 14 overcomes the spring force generated by the spring plate, however.

[0063] When the coil 6 is not energized, the armature disk 4 is pulled to the magnetic body to reduce the air gap present between the armature disk 4 and the magnetic body, so that the armature disk 4 connected rotationally-fixed to the catch 7 or rotor 9 is pressed towards the magnetic body and thus a braking torque is generated.

[0064] When the coil 6 is energized, a counterfield to the magnetic field generated by the permanent magnet is generated, so that less magnetic flux, or no magnetic flux at all, flows via the armature disk 4 and the latter is therefore pulled axially away from the magnetic body by the spring plate.

[0065] The armature disk 4 is thus arranged rotationally-fixed with the rotor 9 but axially movable.

[0066] A torque support part 10 attached to a receiving part by screws is connected, e.g., by further screws, to the inner ring of the magnetic body. Thus, the reaction torque of the brake assembly is transmitted to the housing.

[0067] The torque support part 10 is, for example, arranged axially between the receiving part 2 and the spring elements 12.

[0068] The rotor shaft of the angle sensor 15 is connected rotationally-fixed to the rotor 9 and is arranged rotatable relative to the housing of the angle sensor 15 supported on the inner ring 13 of the magnetic body by the second torque support part 16. To this end, the second torque support part 16 is pressed, e.g., to the inner ring 13 of the magnetic body, by a screw, e.g., the screw head thereof, screwed into an axially oriented threaded hole of the inner ring 13 of the magnetic body.

[0069] In addition, a further auxiliary sheet 17 having a hexagon socket is attached to the inner ring 13 of the magnetic body as an assembly aid by the screw.

[0070] During assembly, the hexagon socket of the auxiliary sheet 17 is first placed in a positive-fit over an external hexagonal-shaped region of the rotor shaft of the angle sensor 15, thus making it possible to screw the rotor shaft of the angle sensor into the rotor 9. It is only after the auxiliary sheet 17 is pressed towards the inner ring 13 of the magnetic body by the screw that this positive-fit hexagonal connection is released due to the axial displacement of the auxiliary sheet 17, and thus the auxiliary sheet 17 if functionless. However, the screw is guided through the auxiliary sheet 17 and the second torque support part 16 and thus the second torque support part 16 is arranged farther removed axially from the housing of the angle sensor 15. In this manner, it is provided very rigid circumferentially, but elastic axially.

[0071] As illustrated in FIG. 3, the first torque support part includes an inner ring region 33 arranged radially inside an outer ring region 34, and crosspieces 32 spaced apart from one another circumferentially connect the inner ring region 33 to the outer ring region 34.

[0072] Holes 30 passing through the first torque support part 10 and through which a screw screwed into the receiving part 2 projects are arranged on the outer ring region 34.

[0073] Holes 31 passing through the first torque support part 10 and through which a screw screwed into the inner ring of the magnetic body projects are arranged on the inner ring 33.

[0074] The crosspieces 32 extend increasingly in the circumferential direction as radial distance increases.

[0075] Thus, for example, the circumferential angle region covered by the specific crosspiece 32 at a specific radial distance is increasingly displaced radially in the circumferential direction. The width of the crosspiece 32 measured in the circumferential direction is, for example, constant at each radial distance.

[0076] As illustrated in FIG. 1 and FIG. 4, in contrast to the foregoing exemplary embodiment, a bellows 40 is provided that the spring elements 12, the first torque support part 10, and also the ring 11.

[0077] The bellows 40 is pressed towards the inner ring 13 of the magnetic body by the second screw 42 and towards the receiving part 2 by the first screw 41. The bellows 40 generates a spring force that acts axially and that generates a spring force oriented from the inner ring 13 of the magnetic body to the second bearing, that is, to the gearbox.

[0078] A connecting part 19 is arranged on the housing part 1 for supplying the brake motor, e.g., the stator winding 21.

[0079] A housing cover 20 is connected to the housing part 1 and also protects the stator winding 21.

[0080] The bellows 40 is, for example, arranged as a metal bellows and at its radially inner end region has a reinforcement, that is, greater wall thickness. During production of the metal bellows 40 from a sheet of constant wall thickness, the region of the reinforcement can be achieved, for example, by folding the sheet and thus creating a double layer. Alternatively, it is also possible to weld on an annular part.

[0081] The first bearing 8 and the second bearing 24 are arranged as roller bearings, e.g., as ball bearings.

[0082] In further exemplary embodiments, a further spring element or spring arrangement replaces the spring plate.

[0083] In further exemplary embodiments, a single spring element or at least one spring packet is employed instead of the spring elements 12. The first connecting elements 5 can also be used for connecting the armature disk 4 to the catch 7.

TABLE-US-00001 LIST OF REFERENCE NUMERALS 1 Housing part 2 Receiving part, e.g., brake bearing shield 3 Outer ring 4 Armature disk 5 Connecting element, e.g., rivet 6 Coil 7 Catch 8 First bearing, e.g., ball bearing 9 Rotor of the electric motor 10 First torque support part, e.g., for the brake assembly 11 Ring 12 Spring elements, e.g., spring packet 13 Inner ring 14 Permanent magnet 15 Angle sensor 16 Second torque support part, e.g., for the angle sensor 15 17 Auxiliary sheet with hexagon socket as assembly aid 18 Electrical supply line for coil 6 19 Connecting part 20 Housing cover 21 Stator winding 22 Flange part, e.g., bearing flange 23 Insulating part for thermal and electrical separation and for receiving the bearing for functional testing 24 Second bearing 30 First hole 31 Second hole 32 Crosspiece 33 Inner ring region 34 Outer ring region 40 Bellows, e.g., metal bellows 41 First screw 42 Second screw