Patent ID: 7780564

Claim:
An automatic transmission hydraulic line pressure regulator, comprising: a spring having a first end and a second end, the second end for engaging a portion of a line pressure valve installed in a valve bore of a valve body of the automatic transmission and axially movable, under influence of the line pressure exposed to a portion of the line pressure valve opposite the portion engaging the spring, between a closed position in a direction away from the spring and an open position in a direction toward the spring, the spring resisting an opening force exerted on the line pressure valve by the line pressure and movement of the line pressure valve from the closed position; a first body for installation and removable fixation in the valve bore distant from the line pressure valve, the first body having a first side positioned toward an exterior of the valve body and a second side positioned toward an interior of the valve body, the first body having a threaded bore passing through the first body from the first body first side to the first body second side; a threaded adjuster axially engaged in the threaded bore of the first body and rotationally adjustable with respect to the first body to alter an axial position of the threaded adjuster with respect to the first body, a first end of the threaded adjuster being accessible from an exterior of the valve body for rotational adjustment; a second body for installation in the valve bore between the threaded adjuster and the spring and having a first side for engaging a second end of the threaded adjuster and a second side for engaging the first end of the spring; wherein, rotational adjustment of the threaded adjuster with respect to the first body also alters both an axial position of the second body and an axial position of the first end of the spring, thereby altering a pre-load on the spring to alter a resistive force against movement of the line pressure valve caused by the line pressure, such that increasing the pre-load on the spring by inward axial movement of the threaded adjuster increases the line pressure because the line pressure valve is prevented from opening and bleeding off further line pressure until the line pressure has increased to a level that the opening force can overcome the increased spring resistive force to open the pressure valve, and correspondingly, decreasing the pre-load on the spring by outward axial movement of the threaded adjuster decreases the line pressure.