Electronic differential lock assembly

• US 8,622,868 B2
• Filed: 01/03/2008
• Issued: 01/07/2014
• Est. Priority Date: 01/31/2003
• Status: Active Grant

• Current Assignee: Meritor Heavy Vehicle Systems Cameri SPA (Meritor, Inc. (Nevada))
• Original Assignee: Meritor Heavy Vehicle Systems Cameri SPA (Meritor, Inc. (Nevada))
• Inventors: Pontanari, Marco, Bassi, Marco, Gianone, Roberto, Bellomi, Giovanni
• Primary Examiner(s): KNIGHT, DEREK DOUGLAS
• Application Number:
  US11/968,756
• Publication Number:
  US 20080103010A1
• Time in Patent Office: 2,196 Days
• Field of Search: 475/240, 475/241, 475/231, 475/249
• US Class Current: 475/231
• CPC Class Codes: F16H 2048/204 Control of arrangements for suppressing differential actions
• CPC Class Codes: F16H 2048/346 using a linear motor
• CPC Class Codes: F16H 2048/426 characterised by spigot bearing arrangement, e.g. bearing for supporting the free end of the drive shaft pinion
• CPC Class Codes: F16H 48/08 comprising bevel gears
• CPC Class Codes: F16H 48/24 using positive clutches or brakes
• CPC Class Codes: F16H 48/30 using externally-actuatable means
• CPC Class Codes: F16H 48/34 using electromagnetic or electric actuators

Abstract

An electronic differential lock assembly includes a shift collar that is movable in response to an electronic signal from an unlocked position where axle shaft speed differentiation under predetermined conditions is permitted to a locked position where a pair of axle shafts is fixed for rotation together. Speed differentiation is provided by a differential that includes a differential gear assembly supported within a differential case. A coil surrounds the shift collar and is selectively energized to move the shift collar from the unlocked position to the locked position. The shift collar is splined to one of the axle shafts and is selectively splined to the differential case to lock the axle shafts together. The electronic differential lock assembly includes a return spring that automatically disengages the shift collar from the differential case once the coil is no longer energized.

Claims

1. A drive axle assembly with a locking differential comprising:

a driving input defining a longitudinal axis;

a carrier including a pinion gear driven by said driving input and a ring gear in meshing engagement with said pinion gear;

a differential including a differential gear assembly supported by a differential case that has a first case half and a second case half that cooperate to surround said differential gear assembly and wherein said ring gear is attached to said first case half to drive said differential gear assembly;

a pair of axle shafts driven by said differential gear assembly for rotation about a lateral axis, said lateral axis being transverse to said longitudinal axis; and

a locking mechanism including a shift collar and an electronic actuator for controlling movement of said shift collar wherein said shift collar is movable between an unlocked position where speed differentiation between axle shafts is permitted and a locked position wherein said shift collar is moved into locking engagement with said second case half in response to an electronic signal such that said differential case, said shift collar and said pair of axle shafts are fixed for rotation together about said lateral axis, said electronic actuator comprises a coil surrounding said shift collar wherein said electronic signal powers said coil to move said shift collar, the drive axle assembly including an axle housing for substantially enclosing said carrier and said pair of axle shafts wherein said coil is supported by said axle housing; and

said coil includes at least one mount portion through which said coil is mounted to an axle housing with at least one fastener.

2. The drive axle assembly as set forth in claim 1 including a microswitch that is fixed to said axle housing adjacent to said coil to monitor differential lock status.