Abstract:
Hydraulic valve actuation systems and methods to provide variable lift for one or more engine air valves by way of a variable position hard stop. Various embodiments are disclosed, including embodiments controlling lift by providing a choice of two different fixed stops, three different fixed stops, stops continuously variable throughout a range of lifts, and a fixed stop and stops continuously variable throughout a range of lifts. The valves controlled by a variable position hard stop may be a single engine intake or exhaust valve, or multiple valves of any number, and of either intake or exhaust valves or both, or of one intake or one exhaust valve for one or more cylinders in engines having more than one intake or exhaust valve per cylinder. Dashpot deceleration of engine valve velocity on opening to the hard stop and on engine valve closure is disclosed, as are other aspects and embodiments of the invention.
Abstract:
Hydraulic valve actuation systems and methods to provide variable lift for one or more engine air valves by way of a variable position hard stop. Various embodiments are disclosed, including embodiments controlling lift by providing a choice of two different fixed stops, three different fixed stops, stops continuously variable throughout a range of lifts, and a fixed stop and stops continuously variable throughout a range of lifts. The valves controlled by a variable position hard stop may be a single engine intake or exhaust valve, or multiple valves of any number, and of either intake or exhaust valves or both, or of one intake or one exhaust valve for one or more cylinders in engines having more than one intake or exhaust valve per cylinder. Dashpot deceleration of engine valve velocity on opening to the hard stop and on engine valve closure is disclosed, as are other aspects and embodiments of the invention.
Abstract:
A ride control system includes a shock absorber having a movable piston that divides the shock absorber into a lower and an upper volume and a center check valve that allows fluid to flow from the upper to the lower volume. A back pressure actuator provides a selectable back pressure to the lower volume. Three two way valves and a check valve allow the lower and upper volumes to be selectively coupled to either the selectable back pressure or a shock absorber fluid reservoir to provide passive, semi-active, or active ride control. The back pressure actuator pressurizes a hydraulic accumulator when shock absorber fluid flows into the back pressure actuator to provide energy recovery.
Abstract:
Micro-hydraulic supply and storage units capable of recovering waste energy and storing energy for later use, such as for operating hydraulic valve actuation and high pressure fuel injection systems. The system includes a sump, a pump motor, an accumulator and a supply rail. Valving is provided to couple the outlet of the pump motor to the accumulator to fill the accumulator with what otherwise would be waste energy, such as when a vehicle is using its engine for braking, directing the output of the pump motor to a supply rail to maintain the pressure in the supply rail, and directing the output of the pump to a sump. The valving also allows directing an outlet of the accumulator to an inlet of the pump motor for recover of the energy in the accumulator. Other aspects of the invention are disclosed.
Abstract:
Hydraulic valve actuation systems and methods to provide variable lift for one or more engine air valves by way of a variable position hard stop. Various embodiments are disclosed, including embodiments controlling lift by providing a choice of two different fixed stops, three different fixed stops, stops continuously variable throughout a range of lifts, and a fixed stop and stops continuously variable throughout a range of lifts. The valves controlled by a variable position hard stop may be a single engine intake or exhaust valve, or multiple valves of any number, and of either intake or exhaust valves or both, or of one intake or one exhaust valve for one or more cylinders in engines having more than one intake or exhaust valve per cylinder. Dashpot deceleration of engine valve velocity on opening to the hard stop and on engine valve closure is disclosed, as are other aspects and embodiments of the invention.
Abstract:
Power steering systems and methods to improve efficiency and performance of vehicle power steering systems. In one embodiment, there is provided an engine driven positive displacement hydraulic pump, a rotary valve coupled to a steering shaft for receiving hydraulic fluid under pressure in a rotary valve inlet and providing a differential pressure to a steering rack piston for a steering boost responsive to a torque exerted on the steering shaft, valving coupled between an output of the hydraulic pump, the rotary valve inlet and the hydraulic pump input for controllably coupling the output of the hydraulic pump to the rotary valve inlet or an input of the hydraulic pump, and a controller coupled to valving to maintain a flow rate of hydraulic fluid coupled to the rotary valve responsive to a pressure sensor output. Other embodiments are disclosed.
Abstract:
Power steering systems and methods to improve efficiency and performance of vehicle power steering systems. In one embodiment, there is provided an engine driven positive displacement hydraulic pump, a rotary valve coupled to a steering shaft for receiving hydraulic fluid under pressure in a rotary valve inlet and providing a differential pressure to a steering rack piston for a steering boost responsive to a torque exerted on the steering shaft, valving coupled between an output of the hydraulic pump, the rotary valve inlet and the hydraulic pump input for controllably coupling the output of the hydraulic pump to the rotary valve inlet or an input of the hydraulic pump, and a controller coupled to valving to maintain a flow rate of hydraulic fluid coupled to the rotary valve responsive to a pressure sensor output. Other embodiments are disclosed.