Patent ID: 6119802
Filing Date: 2000-09-19
Classification: B60K,F16H,Y02T

Abstract:
A fluid drive system in a vehicle comprising:a prime mover including a rotatable driveshaft;an adjustable vehicle control member;a reservoir for maintaining a supply of working fluid;a working circuit including:a plurality of fluid motors, each of said motors being drivingly connected to at least one wheel of the vehicle and including first and second fluid ports;a first working conduit system fluidly connecting to the first fluid port of each of said motors, said first working conduit system including a main working pressure line;a second working conduit system fluidly connected to the second fluid port of each of said motors, said second working conduit system terminating, within said working circuit, in a common, auxiliary working pressure line;motor control valve means interposed between said motors and at least one of said main and auxiliary working pressure lines for establishing fluid communication between at least one of said motors and at least one of said main and auxiliary working pressure lines in a working position and interrupting fluid communication between said motors and said at least one of said main and auxiliary working pressure lines in an isolating position, wherein said plurality of fluid motors are arranged with respect to said first and second working conduits, parallel to one another and at least two of said plurality of fluid motors are drivingly connected to a common output shaft, said common output shaft being drivingly connected to at least one wheel of the vehicle;a pressurizing circuit including:a pump drivingly coupled to the driveshaft of said prime mover, said pump including an inlet in fluid communication with said reservoir and an outlet;an accumulator in fluid communication with the outlet of said pump;a main pressure supply line in fluid communication with said accumulator, said main pressure supply line including a terminal portion located downstream of said accumulator;an adjustable flow control valve located in said main pressure supply line downstream of said accumulator, said adjustable flow control valve being linked to said adjustable vehicle control member such that selective movement of said adjustable vehicle control member repositions said adjustable flow control valve;directional flow control valve means interconnected between said main pressure supply line, said main working pressure line, said auxiliary working pressure line and said reservoir for controlling the flow of working fluid between said working and pressurizing circuits; andmeans for shifting said motor control valves means between said working and isolating positions.