Patent ID: 8567444

Claim:
An accumulator assembly for a motor vehicle powertrain comprising: a valve body having a longitudinal axis, the valve body having an inner surface that defines a bore; an inner sleeve attached to and located within the valve body, the inner sleeve being coaxial with the longitudinal axis of the valve body; a bearing element positioned near an end of the inner sleeve; a follower located within the valve body and being coaxial with the longitudinal axis of the valve body, the follower having a ramp that is engagable with the bearing element and having an outer surface that together with the bore of the valve body define a chamber; an armature positioned within the inner sleeve and being coaxial with the longitudinal axis of the valve body, the armature having a detent that accommodates the bearing element, wherein the armature and the follower are moveable along the longitudinal axis between an unlocked position and a locked position; and a solenoid proximate the armature, the solenoid being operable to move the armature to the unlocked position, wherein the bearing element engages the ramp of the follower in the locked position and disengages from the ramp in the unlocked position, the volume of the chamber in the locked position being greater than the volume of the chamber in the unlocked position, and wherein when the motor vehicle remains on, the solenoid is de-activated and the armature and the follower lock together in the locked position, and wherein the volume of the chamber increases to draw the fluid into the chamber.