TRANSMISSION COMPRISING A DISCONNECT UNIT AND ELECTRIC VEHICLE COMPRISING SUCH A TRANSMISSION

Abstract

A transmission includes an input shaft, configured for receiving torque applied by a motor, a gear system, a differential, at least one output shaft, and a disconnect unit which is switchable between an engaged and a disengaged state. In the engaged state the input shaft is connected to the output shaft via the gear system and the differential for driving the at least one output shaft, and in the disengaged state the at least one output shaft is disconnected from the input shaft. An (electric) vehicle including such a transmission.

Claims

1. A transmission comprising: an input shaft, configured for receiving torque applied by a motor; a gear system; a differential; at least one output shaft, and a disconnect unit which is switchable between an engaged and a disengaged state, wherein in the engaged state the input shaft is connected to the output shaft via the gear system and the differential for driving the at least one output shaft, and wherein in the disengaged state the at least one output shaft is disconnected from the input shaft.

2. The transmission according to claim 1, wherein in the engaged state the disconnect unit engages at least a part of the differential.

3. The transmission according to claim 2, wherein the differential comprises a casing, wherein in the engaged state the disconnect unit engages the casing of the differential.

4. The transmission according to claim 1, wherein the gear system is a planetary gear system; and wherein in the engaged state the disconnect unit engages a planet carrier of the planetary gear system.

5. The transmission according to claim 4, wherein in the engaged state the disconnect unit engages at least a part of the planetary gear system.

6. (canceled)

7. The transmission according to claim 4, wherein the input shaft is rotationally fixed an input of the planetary gear system, such as a sun gear of the planetary gear system.

8. The transmission according to claim 4, wherein in the engaged state, the planet carrier and the casing are rotationally fixed with respect to each other, and wherein in the disengaged state the planet carrier and the casing are rotationally uncoupled.

9. The transmission according to claim 4, wherein the transmission further comprises a bearing arranged between the planet carrier and the casing, said bearing being pretensioned.

10. The transmission according to claim 9, wherein the casing and/or the planet carrier comprises external splines, wherein in the engaged state the disconnect unit engages said external splines; and wherein the disconnect unit comprises a shift sleeve configured to cooperate with said splines on the casing and/or the planet carrier.

11. (canceled)

12. The transmission according to claim 11, wherein the shift sleeve is permanently rotationally coupled to the planet carrier; and wherein the shift sleeve is permanently rotationally coupled to the casing of the differential.

13. (canceled)

14. The transmission according to claim 1, wherein the disconnect unit comprises an actuator for switching between the engaged and the disengaged state.

15. The transmission according to claim 14, wherein the actuator is mounted offset from a central axis of the casing and/or the planet carrier.

16. The transmission according to claim 14, wherein the actuator is rotationally stationary.

17. The transmission according to claim 12, wherein the actuator comprises a solenoid.

18. The transmission according to claim 17, wherein the solenoid comprises an actuatable pin and a first stop, wherein the pin engages the first stop when the solenoid is actuated.

19. The transmission according to claim 17, wherein the solenoid comprises the actuatable pin and further a second stop and a biasing means, wherein the biasing means is configured to bias the actuatable pin towards the second stop, and wherein in the disengaged state the biasing means force the actuatable pin into engagement with the second stop.

20. The transmission according to claim 1, wherein the disconnect unit comprises a lever for switching between the engaged and the disengaged state.

21. The transmission according to claim 20, wherein the lever is actuatable via a pin-slot joint.

22. A vehicle comprising a motor and the transmission according to claim 1, the vehicle being drivable by the motor via the transmission, the vehicle further comprising a second motor for driving the vehicle.

23. (canceled)

24. The vehicle according to claim 22, the vehicle being an electric vehicle.

Description

[0068] The invention will be further elucidated with reference to the attached drawings, in which:

[0069] FIG. 1 shows a schematic of a transmission;

[0070] FIGS. 2A-2D schematically show different perspective views of a transmission, detailing various components; and

[0071] FIG. 3 schematically shows a cross sectional view of a transmission.

[0072] Throughout the figures, like elements will be referred to using like reference numerals. Like elements of different embodiments are referred to using reference numerals increased by one hundred (100).

[0073] The schematic of FIG. 1 shows a transmission 1 and an electric motor 2 configured for driving a first and second output shaft 3, 4 through the transmission 1. The motor 2 drives a sun gear 5 of a planetary gear system 6. Torque is transmitted further via stepped planet gears 7 (only one shown) with a first set of teeth 8 engaging the sun gear 5, and a second set of teeth 9 engaging a ring gear 10. The stepped planet gears 7 are carried by a planet carrier 11.

[0074] The output shafts 3, 4 are driven via a differential 12 which includes a casing 13 configured for receiving torque in order to drive the output shafts 3, 4.

[0075] The casing 13 of the differential 12 and the planet carrier 11 are provided with corresponding splines 14, 15 on their exterior. A shifting sleeve 16 is movably arranged over the external spline 15 of the differential casing 13, so that it can selectively engage or disengage the external spline 14 of the planet carrier 11. Accordingly, rotation of the planet carrier 11 and the differential casing 13 can be coupled or uncoupled by moving the shifting sleeve 16, thus providing an engaged and a disengaged state of a disconnect unit. The shifting sleeve 16 is driven via a lever 17 which pivots about a pivot point 18. The lever 17 is actuated by a solenoid 19 mounted offset from a central axis A of the differential casing 13. The solenoid 19 is fixed in position, as shown by it being connected to an outer transmission casing 24. The solenoid 19 includes an actuatable pin 21 connected to the lever via a pin-and-slot joint 22. Accordingly, movement of the pin 21 from the right to left in FIG. 1 pivots the lever, thereby moving the sleeve 16 from left to right, so that the sleeve 16 engages both external splines 14, 15 of the differential casing 13 and the planet carrier 11. The solenoid 19 further includes a first stop 23 upon which the pin 21 engages when the solenoid 19 is powered. Although not shown in FIG. 1, the solenoid 19 may be further provided with a biasing means biasing the actuatable pin away from the first stop, and optionally a second stop which limits movement of the actuatable pin 21 at a certain distance from the first stop 23.

[0076] FIGS. 2A-2D show a transmission 101 which has a casing 124. An output shaft 104 protrudes from the casing 124. Further an opening 125 can be seen for accommodating another output shaft. The casing 124 also forms a pivot 118 upon which a lever (see FIGS. 2B-2D) can rotate. Further, an electrical connection 126 is exposed, through which the solenoid (see FIGS. 2B-2D) can be powered.

[0077] In FIG. 2B, the casing 124 has been removed to expose the internals of the transmission 101. In FIG. 2C additionally a part of the planet carrier 111 has been removed. Accordingly, stepped planetary gears 107 with first 108 and second 109 sets of teeth can be seen engaging a ring gear 110 of a planetary gear system 106. The planetary gear system 106 is driven via the sun gear 105 (FIG. 2C). the planet carrier 111 has an external spline 114. A differential 112 with a casing 113 is also shown. The differential 112 is provided with an external spline 115 (FIG. 2D) which correspond with the spline 114 of the planet carrier 111. A shift sleeve 116 engages the spline 115 of the differential casing 113 and selectively engages the spline 114 of the planet carrier 111, depending on its axial position. Accordingly, an engaged and a disengaged state are provided. Movement of the shift sleeve is driven via a lever 117 which pivots about a pivot point 118. The lever 117 is connected to the shift sleeve 116 via slide shoes 128 connected to the lever 117 via a pin 127 allowing some rotation of the shoe 128. The shoe 128 slides in a track 128 when the shift sleeve 116 rotates, thereby allowing the lever 117 to be rotationally stationary. Movement of the lever 117 is effected by a solenoid 119 which engages the lever 117 via a pin-and-slot joint 122, which includes a hook 130 attached to an actuatable pin 121 of the solenoid 119, which forms the slot, and a pin 129 fixed to the lever, which forms the pin of the pin-and-slot joint 122 (FIG. 2D).

[0078] FIG. 2C further shows a bearing 199 between the planet carrier 110 and the casing 113 of the differential 112. The bearing 199 is pretensioned, so that a coaxial alignment of the planet carrier 110 and the casing 113 is guaranteed. Pretension is applied by forcing the planet carrier 110 and the differential casing 113 towards each other in the axial direction, as indicated by arrows F.sub.1 and F.sub.2 in FIG. 2B. The required force on the differential casing 113 is applied by the housing 124 via a bearing 150. The required force on the carrier is applied by a lid of the housing 124, also via a bearing (not visible).

[0079] FIG. 3 shows a transmission similar to that of FIGS. 2A-2D. As its components are identical in type to that of FIGS. 2A-2D, reference is herein made only to components not easily visible in that of the preceding figures. In the cross section of FIG. 3, the pretensioned bearing 299 can be seen centrally between the planet carrier 211 and the housing 213 of the differential 206. The bearing 299 is pretensioned in the axial direction, by forcing the housing 213 of the differential 206 towards the planet carrier 211 using a pretension force. The pretension force is applied by the casing 224 of the transmission 201 on the one hand, which produces a force F.sub.1 on the housing 213 of the differential 206 which in FIG. 3 is oriented to the right, and a lid 250 of the transmission housing 224 on the other hand, which produces a force F.sub.2 on the planet carrier 211 which in FIG. 3 is oriented to the left. Both these forces F.sub.1, F.sub.2 are applied via respective bearings 251, 252 between the housing 224 and the planet carrier 211 and the housing 213 of the differential 206 respectively. It is noted some details have been left out in FIG. 3 for simplicity. For those details, reference is made to the other figures and the description above.

[0080] Although the invention has been described above with reference to specific examples and embodiments, the scope of this application is not limited thereto. In fact, the scope is also defined by the following claims.