Control system for a continuously variable transmission

Patent · Tue Jan 03 04:00:00 EST 1989

OSTI ID:6155503

Tanaka, H; Morimoto, Y

This patent describes a control system for a continuously variable transmission for transmitting the power of an internal combustion engine for driving a motor vehicle. The transmission has a drive pulley having a hydraulically shiftable disc and a hydraulic cylinder for operating the disc, a driven pulley including a hydraulically shiftable disc and a hydraulic cylinder for operating the latter disc, and a belt engaged with both pulleys. The control system includes a first hydraulic circuit having a pump for supplying oil to both the hydraulic cylinders, and a transmission ratio control valve having a shiftable spool for controlling the oil supplied to at least one of the cylinders. The improvement in the control system comprises: means for shifting the spool of the transmission ratio control valve; means for sensing operating conditions of the engine and transmission and for producing a first signal dependent on the conditions; means for producing a control signal to shift the spool to control the transmission ratio of the transmission to the desired transmission ratio value; and a means for detecting a steady state driving condition and for producing a steady state signal.

• Assignee: Fuji Jukogyo Kabushiki Kaisha, Tokyo
• Patent Number(s): US 4794819
• OSTI ID: 6155503
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
99 GENERAL AND MISCELLANEOUS
990220 -- Computers
Computerized Models
& Computer Programs-- (1987-1989)
COMPUTERIZED CONTROL SYSTEMS
CONTROL EQUIPMENT
CONTROL SYSTEMS
CORRECTIONS
CYLINDERS
DESIGN
ENGINES
EQUIPMENT
FLOW REGULATORS
HEAT ENGINES
HYDRAULIC EQUIPMENT
INTERNAL COMBUSTION ENGINES
MACHINE PARTS
MEASURING INSTRUMENTS
MECHANICAL TRANSMISSIONS
METERS
OPERATION
PLATES
SIGNAL CONDITIONING
STEADY-STATE CONDITIONS
VALVES