Abstract: A valve actuation system is described containing a collapsible pushrod device for use in a reciprocating piston machine cylinder such as an engine. The collapsible pushrod device replaces a conventional pushrod. The system can include a driver base, plunger, and a deactivation pin assembly. In normal operation, the pins lock the driver base and plunger together thereby providing regular valve motion. Under selected conditions, the pin assembly controller unlocks the driver base from the plunger. Valve lift is reduced or eliminated. When eliminated, the cylinder is deactivated. The system can vary the effective compression ratio between higher for cold starting and other selected operating conditions and lower for warmed-up running, as well as trap additional exhaust residuals to assist starting and light load. This is especially useful for Diesel engines. Various means may be used to unlock the pins including oil pressure, bi-metal spring temperature, or electromagnetic activation.

Abstract: A valve actuation system is described containing a collapsible pushrod device for use in a reciprocating piston machine cylinder such as an engine. The collapsible pushrod device replaces a conventional pushrod. The system can include a driver base, plunger, and a deactivation pin assembly. In normal operation, the pins lock the driver base and plunger together thereby providing regular valve motion. Under selected conditions, the pin assembly controller unlocks the driver base from the plunger. Valve lift is reduced or eliminated. When eliminated, the cylinder is deactivated. The system can vary the effective compression ratio between higher for cold starting and other selected operating conditions and lower for warmed-up running, as well as trap additional exhaust residuals to assist starting and light load. This is especially useful for Diesel engines. Various means may be used to unlock the pins including oil pressure, bi-metal spring temperature, or electromagnetic activation.

Abstract: A two mode valve lifter for Diesel engines which varies the compression ratio between higher for cold starting and other selected operating conditions, and lower for warmed-up running. This is accomplished during engine starting and selected other conditions by causing the intake valve to close early (near bottom center), providing for example, up to three ratios additional compression. The invention incorporates a conventional valve lifter packaged within a sleeve, the sleeve being moved by the engine cam. In its conventional operating mode, the sleeve is rigidly attached to the lifter and the cam moves the assembly to lift the valve in the ordinary manner. When the sleeve is not attached, partial lost motion occurs, causing the valve to open later and close earlier. In the modified mode and as needed, optional damping can be introduced to allow the valve to open and close gradually and quietly.

Abstract: An engine 20 has an oiling system including a pump (46) that delivers oil under nominal engine lubrication pressure to lubricate moving surfaces of the engine mechanism (42). The system also has first and second control passages (30, 32) to effect engine compression ratio change by operating connecting rod length change mechanisms (26A, 26B, 26C). Selectively operated hydraulic control devices cause pressure in the first passage to be greater than pressure in the second passage to effect an increase in engine compression ratio and pressure in the second passage to be greater than pressure in the first passage to effect a decrease in engine compression ratio. Multiple embodiments of the invention are disclosed.