Transfer gear

Patent metadata

Field	Value
Publication number	US-11273708-B2
Application number	US-201816499451-A
Country	US
Kind code	B2
Filing date	Feb 7, 2018
Priority date	Mar 30, 2017
Publication date	Mar 15, 2022
Grant date	Mar 15, 2022

Abstract

The present invention relates to a transfer gearbox having an input shaft, a first output shaft, a second output shaft, a friction clutch, by means of which, in a manner which is dependent on its engagement state, a variable proportion of a drive torque which is transmitted from the input shaft to the first output shaft can be transmitted to the second output shaft, and a rotationally driven actuator unit for controlling the engagement state of the friction clutch. Furthermore, the transfer gearbox has an electromagnetically actuable latch for locking the actuator unit as required.

First claim

The invention claimed is:

1. A transfer gearbox having an input shaft, a first output shaft, a second output shaft, a friction clutch configured to control transmission of a drive torque from the input shaft to the first output shaft and to the second output shaft based on an engagement state of the friction clutch, a rotationally driven actuator unit for controlling the engagement state of the friction clutch, and an electromagnetically actuable latch for selectively locking the actuator unit.

2. The transfer gearbox as claimed in claim 1 , wherein a variable proportion of a drive torque which is transmitted from the input shaft to the first output shaft is transmitted to the second output shaft by the friction clutch in a manner which is dependent on the engagement state of the friction clutch.

3. The transfer gearbox as claimed in claim 1 , wherein the actuator unit comprises at least one rotatable actuator member into which the electromagnetically actuable latch engages for locking the actuator unit.

4. The transfer gearbox as claimed in claim 3 , wherein the actuator member of the actuator unit has a plurality of receptacles for the engagement of the electromagnetically actuable latch.

5. The transfer gearbox as claimed in claim 3 , wherein the actuator member is a ramp ring of the actuator unit, wherein the ramp ring is driven at least indirectly by an electric motor, or wherein the actuator member is a torque transmission element of the actuator unit in a power flow path upstream of the ramp ring, the torque transmission element including an actuator shaft, or a gearwheel which is connected fixedly to the actuator shaft so as to rotate with the actuator shaft, or a cam element which is drive-connected to the actuator shaft.

6. The transfer gearbox according to claim 1 , further including a step-down gear mechanism stage which is driven by the input shaft, a shifting clutch with a first shifting position in which the step-down gear mechanism stage establishes a direct drive connection between the input shaft and the first output shaft, and a second shifting position in which the step-down gear mechanism stage establishes a drive connection between the step-down gear mechanism stage and the first output shaft, and a shifting actuator configured to shift the shifting clutch between its first and its second shifting position, and wherein both the shifting actuator for shifting the shifting clutch and the actuator unit for controlling the engagement state of the friction clutch are drive-connected to an actuator shaft.

7. The transfer gearbox as claimed in claim 6 , wherein for locking as required both of the friction clutch and of the shifting clutch, the electromagnetically actuable latch engages into a gearbox element which is connected fixedly to the shifting actuator, to which end the gearbox element has a plurality of receptacles for the engagement of the electromagnetically actuable latch.

8. The transfer gearbox according to claim 7 , wherein at least one stop is provided and positioned on the gearbox element which has the plurality of receptacles for the engagement of the electromagnetically actuable latch, in such a way that, when the latch bears against the at least one stop, a further rotation of the actuator shaft and therefore shifting the shifting clutch between its first shifting position and its second shifting position are prevented.

9. The transfer gearbox as claimed in claim 8 , wherein the at least one stop includes a first stop and a second stop, the first stop being positioned in such a way that, in the first shifting position of the shifting clutch when the latch bears against the first stop, a further rotation of the actuator shaft and therefore shifting over of the shifting clutch out of its first shifting position and its second shifting position are prevented, and the second stop being positioned in such a way that, in the second shifting position of the shifting clutch when the latch bears against the second stop, a further rotation of the actuator shaft and therefore shifting over of the shifting clutch out of its second shifting position and its first shifting position are prevented.

10. The transfer gearbox as claimed in claim 9 , wherein the plurality of receptacles for the engagement of the electromagnetically actuable latch are spaced apart from one another uniformly along a circular path, whereas the first stop is spaced apart from a first receptacle of the plurality of receptacles and the second stop is spaced apart from a last receptacle of the plurality of receptacles, by in each case a greater clearance.

11. The transfer gearbox according to claim 10 , wherein the latch is axially moveable in response to energization of an electromagnet in response to instructions from a control unit.

12. The transfer gearbox as claimed in claim 11 , wherein the latch is extended in a non-energized state of the electromagnet, in order to be in engagement with one of the stops or one of the plurality of receptacles, whereas the latch is not extended in an energized state of the electromagnet, in order to prevent the latch from passing into engagement with one of the stops or one of the plurality of receptacles.

13. The transfer gearbox as claimed in claim 11 , wherein the electromagnet is energized as a consequence of a user-initiated actuation of the friction clutch or the shifting clutch.

14. The transfer gearbox as claimed in claim 5 , wherein the actuator shaft is driven by the electric motor.

15. The transfer gearbox as claimed in claim 5 , wherein the gearwheel is a worm gear.

16. The transfer gearbox as claimed in claim 6 , wherein the step-down gear mechanism stage is a planetary gear mechanism.

17. A transfer gearbox, comprising:
an input shaft, a first output shaft, and a second output shaft;
a friction clutch configured to control transmission of a drive torque from the input shaft to the first and second output shafts based on an engagement state of the friction clutch;
a rotationally driven actuator unit configured to control the engagement state of the friction clutch; and
an electromagnetically actuable latch configured to selectively lock the actuator unit.

18. The transfer gearbox as claimed in claim 17 , wherein a variable proportion of a drive torque which is transmitted from the input shaft to the first output shaft is transmitted to the second output shaft by the friction clutch in a manner which is dependent on the engagement state of the friction clutch.

19. The transfer gearbox as claimed in claim 17 , wherein the actuator unit comprises at least one rotatable actuator member into which the electromagnetically actuable latch engages for locking the actuator unit.

20. The transfer gearbox as claimed in claim 19 , wherein the actuator member of the actuator unit has a plurality of receptacles for the engagement of the electromagnetically actuable latch.

Assignees

• Magna powertrain gmbh & co kg

Inventors

• Bruhn Florian
• Stocker Martin

Classifications

• B60K23/08 Primary

  for changing number of driven wheels {, for switching from driving one axle to driving two or more axles (B60K17/3515 takes precedence)} · CPC title

• B60K17/344

  having a transfer gear · CPC title

• B60K2023/0825

  for adding torque to the front wheels · CPC title

• B60Y2400/405

  Electric motors actuators · CPC title

• B60K5/02

  with the engine main axis, e.g. crankshaft axis, substantially in or parallel to the longitudinal centre line of the vehicle · CPC title