US 7,351,176 B1 · Line-to-lube pressure regulator valve assembly

Abstract

A line-to-lube pressure regulator valve assembly for an automatic transmission including an internal check valve that opens in the Park gear range and at low engine speeds to feed line pressure to the torque converter in response to a substantially lower hydraulic fluid pressure than is required to open the pressure regulator valve in its factory specified operating range. As engine speed increases and sufficient hydraulic fluid pressure is built up within the torque converter charge circuit, the present internal check valve is again closed and the pressure regulator valve assembly opens as it would normally to feed line pressure to the torque converter directly. When the engine is shut off, the present internal check valve is biased to a closed position preventing transmission fluid from draining back through the valve to the transmission sump thereby eliminating the converter drain back problem.

Claims12

Dependent claims

A pressure regulator valve assembly for an automotive transmission having a hydraulic pump disposed in fluid communication with a torque converter via a torque converter charge circuit, said pressure regulator valve comprising:

a valve piston having a plurality of concentric control diameters formed thereon for regulating the flow of automatic transmission fluid from the hydraulic pump to the torque converter;
a compression spring arranged in coaxial relation to said valve piston, said compression spring biasing said valve piston to a closed position in relation to said torque converter charge circuit;
and
bypassing means integrated within said valve piston, wherein said bypassing means comprises an internal check valve including a cylindrical dowel pin disposed within a valve chamber formed in said valve piston, said dowel pin being spring biased to a closed position in relation to said torque converter charge circuit by a calibrated check valve spring disposed about a vented spring guide positioned in coaxial relation to said dowel pin, said internal check valve releasing hydraulic fluid to the torque converter in response to less hydraulic pressure than is required to open said valve piston against the force of said compression spring.

1 more element

A method for continuously filling a torque converter in an automatic transmission of a motor vehicle operating at low engine speed, wherein the transmission includes a hydraulic pump, a torque converter, and a pressure regulator valve disposed in a valve body of the transmission in fluid communication with the hydraulic pump via a pump output circuit and the torque converter via a torque converter charge circuit, said pressure regulator valve functioning to regulate the flow of automatic transmission fluid from the hydraulic pump to the torque converter responsive to pump operating speed, said method comprising the steps of:

providing a replacement pressure regulator valve including an internal check valve therein comprising a dowel pin being spring biased to a closed position in relation to said torque converter charge circuit by a check valve spring disposed about a vented spring guide positioned in coaxial relation to said dowel pin;
positioning said replacement pressure regulator valve within said valve body such that said internal check valve is disposed in fluid communication with said pump output circuit and said torque converter charge circuit;
opening said internal check valve at low engine speed such that transmission fluid is released to said torque converter via said torque converter charge circuit in response to lower hydraulic pressure than is required to open said pressure regulator valve in a factory specified operating range;
and
closing said internal check valve at high engine speed when said pressure regulator valve opens in said factory specified operating range.

2 more elements

Dependencies are inferred from the claim text.

Line-to-lube pressure regulator valve assembly

Life of this patent

Line-to-lube pressure regulator valve assembly

Life of this patent

Abstract

Claims12