US 5,255,641 A · Variable engine valve control system

Abstract

A variable engine valve control system wherein each of the reciprocating intake and/or exhaust valves is hydraulically controlled and includes a piston subjected to fluid pressure acting on surfaces at both ends of the piston. The space at one end of the piston is connected to a source of high pressure fluid while the space at the other end is connected to a source of high pressure fluid and a source of low pressure fluid, and disconnected from each through action of controlling means such as solenoid valves. The controlling means may include a rotary hydraulic distributor coupled with each solenoid valve, thereby permitting each solenoid valve to control operation of a plurality of engine valves in succession. Equal air delivery to all engine cylinders having the aforementioned variable valve control system is assured by controlling electric pulses of variable duration and timing, the system involving means for making individual modifications of the durations of the electric pulses controlling each individual actuator, and the modifications being of such nature as to assure that all actuators control the engine intake (or exhaust) valves in an identical manner to assure equal valve strokes in all cylinders.

Claims15

Dependent claims

A hydraulically operated valve control system for an internal combustion engine, said system comprising:

a high pressure source of fluid and a low pressure source of fluid;
a cylinder head member adapted to be affixed to the engine and including an enclosed cavity;
a poppet valve shiftable between a first and second position within said cylinder head member;
a hydraulic actuator including a piston coupled to the poppet valve and reciprocable within the enclosed cavity which thereby varies in displacement as the poppet valve moves;
said cylinder head member having a high pressure port extending between the enclosed cavity and the high pressure source of fluid and a low pressure port extending between the enclosed cavity and the low pressure source of fluid;
a high pressure valve and a low pressure valve for respectively regulating the flow of fluid in the high pressure and the low pressure ports;
and
control means cooperating with the high and low pressure valves for selectively coupling the enclosed cavity to the high pressure and low pressure sources to oscillate the poppet valve in timed relation to engine operation, wherein during each oscillation, some of the high pressure fluid used to reciprocate the poppet valve is returned to the high pressure source, thereby allowing that the net fluid flow between the high pressure and low pressure sources may be substantially less than the volume swept by the piston.

5 more elements

In an internal combustion engine, an engine valve control system in which the valve stroke is controlled by varying timing and duration of electric signals sent to individually dedicated engine valve controlling means, the system comprising:

a controller programmed to send variable electric control signals to the said engine valve controlling means, said control signals duration comprising the algebraic sum of a basic signal duration and a correction signal duration;
means for generating a basic signal duration determined by the controller as a function of engine operating conditions and being equal for all engine intake valves and equal for all engine exhaust valves;
and
means for generating a correction signal predetermined for each of the engine valve controlling means as a measure of the extent the performance of each engine valve controlling means varies from a predetermined standard, said correction signal generating means being operative in timed sequence to supply to the controller said predetermined correction signal just prior to a respective engine valve controlling means being activated.

1 more element

Dependencies are inferred from the claim text.

Variable engine valve control system

Life of this patent

Variable engine valve control system

Life of this patent

Abstract

Claims15