Heretofore the prior art has proposed various pressure control devices for use in a control system of an automatic transmission of an automotive vehicle.
Some of such pressure control devices comprise a fluid pressure positionable spool valve, the magnitude of the fluid pressure being determined by an armature and cooperating servo-like orifice or passage means. That is, in at least some of such pressure control devices, the more nearly the armature closes the servo-like orifice the greater becomes the magnitude of fluid pressure acting upon the spool valve to cause positioning thereof.
Further, in such prior art arrangements, it is not unusual to provide spring means for resiliently urging the armature means as toward the servo orifice means. This is usually done by having a generally axially extending spring seat member engaging one end of the spring means and being threadably engaged with surrounding structure as to thereby be axially movable, relative to the surrounding structure, to bring about an adjustment of the spring means as, for example, a preload thereof.
Such prior art pressure control devices did present problems in that concentricities of various surfaces had to be maintained to critical tolerances and such tolerances could not always be met or be what was desired from a manufacturing standpoint. The problem or problems of concentricity also occurred with respect to the spring seat member of the prior art.
The invention as herein disclosed and described is primarily directed to the solution of the foregoing as well as other related and attendant problems of the prior art.
USPTO Backgrounds
USPTO Backgrounds