drive unit

Abstract

A drive unit comprises a housing (60), a prime mover having a stator (70) and a rotor (71), a rotor bearing (44), and a differential gear having an input element (4), a first output shaft (5), a second output shaft (6), and a carrier element. The rotor (71) is mechanically operatively connected to the differential gear via the input element (4). The differential gear is configured to distribute torque from the input element (4) to the first output shaft (5) and the second output shaft (6). The differential gear is arranged in an axial direction between the prime mover and the housing cover (61). The rotor (71) is rotatably mounted on the carrier element via the rotor bearing (44). The housing cover (61) is removably fastened to the housing (60). The carrier element is arranged on a drive side of the differential gear. The carrier element rotatably supports a gear set element of the differential gear.The support element extends radially outside the stator (70). The support element is removably connected to the housing (60). The housing (60) is pot-shaped on one drive side.

Description

Technical area

[0001] The present invention relates to a drive unit with a housing and to a vehicle with a drive unit. State of the art

[0002] Drive units with a housing are known. A housing may have an intermediate wall to support gear elements and bearings. However, mounting the drive unit from different sides relative to the housing may be necessary. Description of the invention

[0003] It is an object of the present invention to provide a drive unit having a housing with a simplified design and enabling easy assembly of the drive unit.

[0004] The object is achieved by a drive unit having the features of claim 1. Advantageous further developments are the subject of the dependent claims.

[0005] A drive unit includes a housing, a prime mover with a stator and a rotor, a rotor bearing, and a differential gear. The differential gear includes an input element, a first output shaft, a second output shaft, and a carrier element. The rotor is mechanically connected to the differential gear via the input element. The differential gear is configured to distribute torque from the input element to the first output shaft and the second output shaft. The differential gear is arranged in an axial direction between the prime mover and the housing cover.

[0006] The rotor is rotatably mounted on the support element via the rotor bearing.

[0007] The rotor bearing can be arranged on an inner circumference of a portion of the support element. The rotor bearing can be arranged on an outer circumference of the rotor. This eliminates the need for an intermediate wall for accommodating the rotor bearing.

[0008] The housing cover is attached to the housing. The housing cover is removable from the housing. The carrier element is arranged on a drive side of the differential gear. The carrier element rotatably supports a gear set element of the differential gear. The carrier element extends in a radial direction outside the stator. The carrier element can project beyond the stator in the radial direction. The carrier element is connected to the housing. The carrier element is removable from the housing. The housing is pot-shaped on a drive side. The housing can have a pot shape. The drive side can be a side of the drive unit on which the drive motor is arranged.

[0009] If two elements are mechanically operatively connected, they are directly or indirectly coupled to one another in such a way that a movement of one element causes a reaction in the other element. For example, a mechanical operative connection can be provided by a positive or frictional connection. The mechanical operative connection can correspond to the meshing of corresponding toothings of the two elements. Additional elements, such as one or more spur gear stages, can be provided between the elements. A permanently rotationally fixed connection between two elements, on the other hand, is understood to be a connection in which the two elements are rigidly coupled to one another in all intended states of the transmission. The elements can be present as individual components that are connected to one another in a rotationally fixed manner or as a single piece.A switching element, such as a clutch or brake, can be used to selectively establish or break a rotationally fixed connection between two elements.

[0010] The rotor, the input element, the first output shaft, and the second output shaft can be arranged coaxially with each other. The first output shaft can extend through the housing in the axial direction on the drive side to the outside of the housing. The second output shaft can extend through the housing cover in the axial direction on a transmission side to the outside of the housing cover. The transmission side can be arranged opposite the drive side in the axial direction with respect to the drive unit.

[0011] The rotor can be connected to the input element in a rotationally fixed manner. The rotor can be integral with the input element. The rotor can form the input element on the transmission side of the rotor.

[0012] The housing cover can be attached to the housing via at least one connection section. The connection section can be arranged in the radial direction outside at least one of the stator, the support element, and the differential gear. The housing cover can be attached to the housing via screw connections. One of the screw connections can have a screw. The screw connections can be arranged distributed in the circumferential direction. The screw connections can have screw axes that are aligned in the axial direction. Several of the screw connections can be arranged equidistant from a rotational axis of the rotor. The screw connections can be arranged in the radial direction outside at least one of the stator, the support element, and the differential gear. The screw connections can be configured at an end section of the housing on the transmission side.In this respect, the screw connections can be designed such that an outer circumference, for example an outer diameter, of the housing is large in the radial direction only at the end section on the transmission side. The housing can have its largest circumference in the radial direction at the end section on the transmission side.

[0013] The gear cover can be designed to cover the housing on the gear side. The gear cover can be designed to close the gear. The gear cover can be designed to seal the gear in a fluid-tight manner, for example, oil-tight.

[0014] The housing may be closed on the drive side. The housing may have a bottom section on the drive side. The first output shaft may extend through the bottom section in the axial direction. The bottom section may have a pot-shaped bottom of the housing. An inner circumference, for example a diameter, of the housing may become gradually smaller towards the output side. The inner circumference of the housing may be designed such that no undercut occurs from the transmission side to the drive side. The housing may be designed such that the prime mover, one or more bearings, and the differential gear can be mounted in the housing from the transmission side.

[0015] The housing can be manufactured separately from the carrier element. The housing can be designed such that the carrier element can be inserted into the housing from the transmission side. Movement of the carrier element relative to the housing can be limited in the axial direction by means of at least one securing element. One of the securing elements can be designed as a shoulder element. The shoulder element can extend in the circumferential direction. The shoulder element can have an end face extending in the radial direction. The carrier element can bear against the shoulder section via an end face extending in the radial direction. One of the securing elements can be designed as a retaining ring. Movement of the carrier element in the circumferential direction can be limited by an anti-rotation element. An anti-rotation element can be formed by a driver geometry or claw geometry.An outer circumference of the support element may be larger than an outer circumference of the drive motor. The support element may be connected to the housing via a connecting section. The connecting section may be arranged radially outside the stator.

[0016] In one embodiment, the rotor bearing can be arranged on the transmission side of the drive motor in the axial direction. The rotor can be rotatably mounted on the housing via a second rotor bearing. The second rotor bearing can be arranged on the drive side with respect to the rotor.

[0017] The second rotor bearing can be arranged on an inner circumference of a portion of the support element. The rotor bearing can be arranged on an outer circumference of a portion of the rotor.

[0018] In one embodiment, the first output shaft may extend axially through the support member, the input member, and the rotor. The first output shaft may be rotatably mounted on the housing via a first output shaft bearing. The first output shaft bearing may be arranged on the drive side relative to the second rotor bearing.

[0019] The bearing for the first output shaft can be arranged on an inner circumference of a portion of the housing. The bearing for the first output shaft can be arranged on an outer circumference of a portion of the first output shaft. An outer circumference, for example an outer diameter, of the bearing for the first output shaft can be smaller than an outer circumference, for example an outer diameter, of the second rotor bearing.

[0020] In one embodiment, the second output shaft can be rotatably mounted on the housing cover via a second output shaft bearing. The second output shaft bearing can be arranged on an inner circumference of a portion of the housing cover. The second output shaft bearing can be arranged on an outer circumference of a portion of the second output shaft.

[0021] In one embodiment, the differential gear may have a first gear set and a second gear set. The first gear set may be mechanically operatively connected to the second gear set. The first gear set may be mechanically operatively connected to the input element for receiving torque. The first gear set may be mechanically operatively connected to the first output shaft for outputting torque. The second gear set may be mechanically operatively connected to the second output shaft for outputting torque.

[0022] In one embodiment, the first gear set can be formed by a first planetary gear set. The second gear set can be formed by a second planetary gear set.

[0023] The first planetary gear set may include a first sun gear, a first planet carrier, a first planet pin, a first planet gear, and a first ring gear.

[0024] The first sun gear can mesh with the first planetary gear. The first planetary gear can mesh with the first ring gear. The first planetary gear can be rotatably mounted on the first planetary pin. The first planetary pin can be connected to the first planetary carrier.

[0025] The second planetary gear set may include a second sun gear, a second planet carrier, a second planet pinion, a second planet gear, and a second ring gear. The second sun gear may mesh with the second planet gear. The second planet gear may mesh with the second ring gear. The second planet gear may be rotatably mounted on the second planet pinion. The second planet pinion may be connected to the second planet carrier.

[0026] The first planetary gear set and the second planetary gear set can be arranged in the same plane in the axial direction. The second planetary gear set can be arranged outside the first planetary gear set in the radial direction. The first planetary gear set and the second planetary gear set can be arranged offset from one another in the axial direction.

[0027] The carrier element can rotatably support a planetary gear as a gear set element of the differential gear via a planetary pin. The carrier element can be formed by the second planetary carrier.

[0028] In one embodiment, the first planetary gear set may include at least a first element, a second element, and a third element. The second planetary gear set may include at least a first element, a second element, and a third element. The first element of the first planetary gear set may be rotationally fixedly connected to the input member. The second element of the first planetary gear set may be rotationally fixedly connected to the first output shaft. The first output shaft may be rotationally fixedly connected to the second element of the first planetary gear set with respect to the rotor bearing on the transmission side.

[0029] The third element of the first planetary gear set can be rotationally fixedly connected to the first element of the second planetary gear set. The third element of the first planetary gear set can be rotationally fixedly connected to the first element of the second planetary gear set via a sun gear ring. The sun gear ring can form the third element of the first planetary gear set on an inner circumference. The sun gear ring can form the first element of the second planetary gear set on an outer circumference. The second element of the second planetary gear set can be rotationally fixedly connected to the housing. The third element of the second planetary gear set can be rotationally fixedly connected to the second output shaft.

[0030] The first and second planetary gear sets can be designed as minus planetary gears or as plus planetary gears.

[0031] If the first or second planetary gear set is designed as a negative planetary gear set, the respective second element can be formed by the planet carrier. The respective third element can be formed by the ring gear.

[0032] If the first or second planetary gear set is designed as a positive planetary gear set, the respective second element can be formed by the ring gear. The respective third element can be formed by the planet carrier.

[0033] In one embodiment, the first sun gear of the first planetary gear set can be rotationally fixedly connected to the input element. The first planet carrier of the first planetary gear set can be rotationally fixedly connected to the first output shaft. The first ring gear of the first planetary gear set can be rotationally fixedly connected to the first sun gear of the second planetary gear set. The second ring gear of the second planetary gear set can be rotationally fixedly connected to the second output shaft. The second planet carrier of the second planetary gear set can form the carrier element. In this case, the first planetary gear set and the second planetary gear set can each be configured as a minus planetary gear set.

[0034] In one aspect, a vehicle comprises a drive unit according to any one of the preceding embodiments and at least two drive wheels. The drive unit is configured to drive the drive wheels. One of the drive wheels is configured to drive the vehicle via the first output shaft. The other of the drive wheels is configured to drive the vehicle via the second output shaft.

[0035] Joints can be arranged between each of the first output shaft and the second output shaft and the respective first drive wheel and the second drive wheel to achieve a steering angle or a spring travel, or a combination thereof. The drive motor can be an electric motor or an internal combustion engine. Short description of the characters Fig. 1 shows a sectional view of a schematic representation of an embodiment of a drive unit. Detailed description of embodiments

[0036] Fig. Figure 1 shows a sectional view of a schematic representation of an embodiment of a drive unit. The drive unit comprises a housing 60, a drive motor with a stator 70 and a rotor 71, a rotor bearing 44, and a differential gear. The differential gear comprises an input element 4, a first output shaft 5, a second output shaft 6, a first gear set, in this case a first planetary gear set 10, a second gear set, in this case a second planetary gear set 20, and a carrier element.

[0037] The carrier element is formed in this case by a second planet carrier 22 of the second planetary gear set 20. The carrier element rotatably supports a gear set element, in this case a first planetary gear, of the differential gear. The rotor 71 is rotatably mounted on the carrier element via the rotor bearing 44. As a result, no intermediate wall needs to be provided in the housing 60 to support the rotor bearing 44.

[0038] The carrier element is arranged on a drive side of the differential gear, i.e., between the drive motor and the differential gear. The carrier element extends radially outside the stator 70. The carrier element is removably attached to the housing 60. This allows for a simple construction of the housing 60 and easy assembly of the drive unit.

[0039] Further details of the drive unit are described below.

[0040] The first planetary gear set 10 includes the first sun gear, a first planet carrier, a number of first planet pinions, a number of first planet gears, and a first ring gear. The first sun gear meshes with one of the first planet gears. One of the first planet gears meshes with the first ring gear and is rotatably mounted on one of the first planet pinions. The first planet pinions are connected to the first planet carrier.

[0041] The second planetary gear set 20 includes a second sun gear, the second planet carrier 22, a number of second planet pinions, a number of second planet gears, and a second ring gear. The second sun gear meshes with one of the second planet gears. One of the second planet gears meshes with the second ring gear and is rotatably mounted on one of the second planet pinions. The second planet pinions are connected to the second planet carrier 22.

[0042] The second planetary carrier 22 is non-rotatably connected to the housing 60 via a connecting portion. The connecting portion extends in the circumferential direction. The connecting portion is arranged radially outside an outer circumference of the stator 70.

[0043] The rotor 71 is mechanically operatively connected to the differential gear via the input element 4. The input element 4 forms the first sun gear of the first planetary gear set 10 on an outer circumference of an end portion of the input element 4 on a transmission side, i.e., a side on which the transmission is arranged. The first planet carrier is rotationally fixedly connected to the first output shaft 5 for outputting torque from the first planetary gear set 10. The second ring gear is rotationally fixedly connected to the second output shaft 6 for outputting torque from the second planetary gear set 20. The differential gear is arranged in an axial direction between the drive motor and the housing cover 61.

[0044] The first output shaft 5 and the second output shaft 6 are arranged coaxially with the input element 4. The first output shaft 5 extends in the axial direction through the input element 4 and the rotor 71. The first output shaft 5 and the second output shaft 6 extend in opposite directions in the axial direction.

[0045] The housing cover 61 is connected to the housing 60 in a rotationally fixed manner via screw connections. The screw connections are arranged in a circumferential direction equidistant from a rotational axis of the rotor 71. The screw connections are arranged in the radial direction outside the support element, the stator 70, and the differential gear. One screw connection has a screw with a screw axis that is aligned in the axial direction. The second output shaft 6 is rotatably mounted on the housing cover 61 via a bearing 42 for the second output shaft 6. The bearing 42 for the second output shaft 6 is arranged on an inner circumference of a portion of the housing cover 61. The bearing 42 for the second output shaft 6 is arranged on an outer circumference of a portion of the second output shaft 6.

[0046] The rotor bearing 44 is arranged on the transmission side in the axial direction relative to the rotor 71. The rotor bearing 44 is arranged between the prime mover and the differential gear. The rotor 71 is rotatably supported on the housing 60 via a second rotor bearing 45. The second rotor bearing 45 is arranged on the drive side relative to the rotor 71. The second rotor bearing 45 is arranged on an inner circumference of a portion of the housing 60. The second rotor bearing 45 is arranged on an outer circumference of a portion of the rotor 71.

[0047] The first output shaft 5 is connected via a bearing 41 for the first output shaft 5, left in Fig.1, is rotatably mounted on the housing 60. The bearing 41 for the first output shaft 5 is arranged on the drive side with respect to the second rotor bearing 45. The bearing 41 for the first output shaft 5 is arranged on an inner circumference of a portion of the housing 60. The bearing 41 for the first output shaft 5 is arranged on an outer circumference of a portion of the first output shaft 5. An outer circumference of the bearing 41 for the first output shaft 5 has a smaller diameter than an outer circumference of the second rotor bearing 45.

[0048] In this respect, the housing 60 is pot-shaped in the axial direction toward the transmission side. An inner circumference of the housing 60 gradually decreases in the axial direction toward the drive side. The housing 60 has an end portion in the axial direction on the drive side. The first output shaft 5 extends through the end portion of the housing 60. The end portion forms a bottom of the pot shape of the housing 60. Reference symbol 5 First output shaft 6 Second output shaft 10 First planetary gear set 20 Second planetary gear set 22 Second planet carrier 41 bearings for the first output shaft 42 bearings for the second output shaft 44 rotor bearings 45 second rotor bearing 60 housings 61 Housing cover 70 Stator 71 Rotor

Claims

[1] Drive unit comprising a housing (60), a drive machine having a stator (70) and a rotor (71), a rotor bearing (44) and a differential gear having an input element (4), a first output shaft (5), a second output shaft (6) and a carrier element, wherein the rotor (71) is mechanically connected to the differential gear via the input element (4), the differential gear is designed to distribute a torque from the input element (4) to the first output shaft (5) and the second output shaft (6) and is arranged in an axial direction between the drive motor and the housing cover (61), the rotor (71) is rotatably mounted on the support element via the rotor bearing (44), the housing cover (61) is removably attached to the housing (60), the carrier element is arranged on a drive side of the differential gear, rotatably supports a gear set element of the differential gear and extends in a radial direction outside the stator (70), the support element is removably connected to the housing (60), and the housing (60) is pot-shaped on one drive side. [2] Drive unit according to claim 1, characterized by , that the rotor bearing (44) is arranged in the axial direction on the transmission side of the drive machine and the rotor (71) is rotatably mounted on the housing (60) via a second rotor bearing (45), and the second rotor bearing (45) is arranged on the drive side with respect to the rotor (71). [3] Drive unit according to claim 2, characterized by , that the first output shaft (5) extends in the axial direction through the carrier element, the input element (4) and the rotor (71) and is rotatably mounted on the housing (60) via a bearing (41) for the first output shaft (5), and the bearing (41) for the first output shaft (5) is arranged on the drive side with respect to the second rotor bearing (45). [4] Drive unit according to one of the preceding claims, characterized by that the second output shaft (6) is rotatably mounted on the housing cover (61) via a bearing (42) for the second output shaft (6). [5] Drive unit according to one of the preceding claims, characterized by , that the differential gear has a first gear set and a second gear set, the first gear set is mechanically connected to the second gear set, the first gear set is mechanically connected to the input element (4) to absorb a torque, the first gear set is mechanically connected to the first output shaft (5) to output a torque, and the second gear set is mechanically connected to the second output shaft (6) for outputting a torque. [6] Drive unit according to claim 5, characterized by that the first gear set is formed by a first planetary gear set (10) and the second gear set is formed by a second planetary gear set (20). [7] Drive unit according to claim 6, characterized by , that the first planetary gear set (10) has at least a first element, a second element and a third element and the second planetary gear set (20) has at least a first element, a second element and a third element, the first element of the first planetary gear set (10) is connected in a rotationally fixed manner to the input element (4), the second element of the first planetary gear set (10) is connected in a rotationally fixed manner to the first output shaft (5), the third element of the first planetary gear set (10) is connected in a rotationally fixed manner to the first element of the second planetary gear set (20), the second element of the second planetary gear set (20) is connected in a rotationally fixed manner to the housing (60), and the third element of the second planetary gear set (20) is non-rotatably connected to the second output shaft (6). [8] Drive unit according to claim 7, characterized by , that a first sun gear of the first planetary gear set (10) is connected in a rotationally fixed manner to the input element (4), a first planet carrier of the first planetary gear set (10) is connected in a rotationally fixed manner to the first output shaft (5), a first ring gear of the first planetary gear set (10) is rotationally fixedly connected to a first sun gear of the second planetary gear set (20), a second ring gear of the second planetary gear set (20) is connected in a rotationally fixed manner to the second output shaft (6), and a second planet carrier (22) of the second planetary gear set (20) forms the carrier element. [9] Vehicle with a drive unit according to one of the preceding claims and at least two drive wheels, wherein the drive unit is designed to drive the drive wheels, one of the drive wheels is arranged to drive the vehicle via the first output shaft (5), and the other of the drive wheels is arranged to drive the vehicle via the second output shaft (6).

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