Variator lockout valve system

摘要

A variator lockout valve system for a continuously variable transmission includes a pair of shift valves. Each shift valve has at least one port that is fluidly coupled to a variator of the continuously variable transmission. Electro-hydraulic actuators control the position of each of the shift valves. When the shift valves are in one position, pressure control valves supply fluid pressure to the variator. If one of the shift valves is in another position, one of the pressure control valves is blocked from supplying fluid pressure to the variator.

主权项

1. A variator control circuit, comprising:
a first shift valve movable from a first position to a second position axially spaced from the first position in a first valve chamber of a hydraulic control circuit for a continuously variable transmission, the first shift valve having a first port in fluid communication with a variator of the continuously variable transmission, a first trim valve operable to output variable fluid pressure, the first trim valve being fluidly coupled to the first port when the first shift valve is in the first position, the first trim valve being disconnected from the first port when the first shift valve is in the second position, a second shift valve movable from a first position to a second position axially spaced from the first position in a second valve chamber of the hydraulic control circuit of the continuously variable transmission, the second shift valve having a second port in fluid communication with the variator of the continuously variable transmission, and a second trim valve operable to output variable fluid pressure, the second trim valve being fluidly coupled to the second port when the second shift valve is in the first position, the second trim valve being disconnected from the second port when the second shift valve is in the second position.