Patent ID: 7559415

Claim:
A synchronizer for first and second drives disposed for relative rotation about a common axis and secured against axial movement relative to one another, said first drive having a first fluid passage extending at least partially therethrough, said synchronizer comprising: a hub affixed with said first drive, said hub having a second fluid passage fluidly connected with said first fluid passage; a piston sealably mounted on said hub forming a control volume between said piston and said hub, said control volume intersecting with said second passage, said piston having movement along said common axis in response to fluid pressure within said control volume; a synchronizer cone rotated with said hub having a friction surface angled with respect said common axis, said synchronizer cone being move by said piston; a friction surface rotating with said second drive for engagement with said synchronizer cone to synchronize said first and second drives together; first teeth rotating with said hub being moved by said piston along said common axis; and second teeth rotating with said second drive for meshed contact with said first teeth by virtue of movement of said piston.