Manual valve for automatic transmission

In an automatic transmission including a manual valve having a primary control land for regulating the flow of hydraulic fluid within the valve body of said transmission to provide proper operation for a selected gear range including Park, Reverse, Neutral, Drive, Manual Second, and Manual Low gear ranges, said transmission further including a Pressure Regulator Valve in fluid communication with said Manual Valve and also with torque converter/cooler charge circuits within said valve body, the method of increasing hydraulic fluid flow to the said torque converter/cooler charge circuits in the Park gear range, said method comprising the steps of:

• providing a replacement manual valve including backpressure generating means and a secondary control land for blocking the flow of hydraulic fluid to exhaust circuits when said Park gear range is selected;
• blocking the flow of said hydraulic fluid to said exhaust circuits with said secondary control land;
• redirecting the flow of said hydraulic fluid to an alternate exhaust circuit integrated within said replacement manual valve;
• generating a predetermined backpressure within a first hydraulic circuit interconnecting said replacement manual valve and said Pressure Regulator Valve;
• and
• actuating said Pressure Regulator Valve responsive to said backpressure to increase the flow of said hydraulic fluid via a second hydraulic circuit to said torque converter/cooler charge circuits.

A manual valve for providing proper operation of an automatic transmission in a selected gear range including Park, Neutral, Reverse, Drive, Manual Second, and Manual Low gear ranges, comprising:

• a valve piston having a plurality of concentric control lands formed thereon including a Park control land, a primary control land, and a secondary control land, said secondary control land functioning to block the flow of hydraulic fluid to pressure reducing circuits in said Park gear range;
• an exhaust channel formed within said piston coextensive with the longitudinal axis at a first end thereof;
• and
• at least one fluid control orifice disposed in fluid communication with said exhaust channel for generating backpressure within a first fluid circuit in a valve body within said transmission to effect an increased flow of said hydraulic fluid within a second fluid circuit thereby supplying a torque converter circuit and a transmission cooler circuit when said Park gear range is selected.

A manual valve for use in combination with a valve body of an automatic transmission comprising:

• a valve piston having a plurality of concentric control lands formed thereon including a Park control land, a primary control land, a secondary control land, said secondary control land functioning to block the flow of hydraulic fluid to pressure reducing circuits in the Park gear range and a reverse metering control land, said reverse metering control land regulating the flow of hydraulic fluid within a reverse circuit of said valve body to reduce hydraulic fluid shock acting upon a reverse servo piston when Reverse gear range is selected;
• an exhaust channel formed within said piston coextensive with the longitudinal axis at a first end thereof;
• and
• at least one fluid control orifice disposed in fluid communication with said exhaust channel for generating backpressure within a first fluid circuit in said valve body to effect an increased flow of said hydraulic fluid within a second fluid circuit when said Park gear range is selected.