A technique for testing a pushrod valvetrain in an engine includes replacing an original pushrod with an instrumented pushrod (IPD) which includes a sensor configured to measure strain and/or motion. The engine is then operated, and the output of the sensor is monitored for anomalies. Diagnosis and repair of identified defects may then follow.

There is provided a variable valve apparatus including: a plurality of rocker arms; a coupling pin disposed in a housing hole of the rocker arm closer to one side; a release pin disposed in a housing hole of the rocker arm closer to the other side; a pressing member; a transmission member; and a push-back member disposed so as to push back the transmission member from the other side. The pressing member is configured to push the coupling pin into the housing hole of the rocker arm closer to the other side to couple the plurality of rocker arms. The transmission member is configured to push back the coupling pin into the housing hole of the rocker arm closer to the one side to release a coupling of the plurality of rocker arms.

A system for monitoring operation of an internal combustion engine having a rocker arm assembly for actuating an engine valve is disclosed. The rocker arm assembly includes a first arm with a first end and a second end, at least one slider pad connected to the first arm near the second end of the first arm, a second arm also having a first end pivotally connected near the first end of the first arm along a pivot axle, a latch that when latched secures the first arm relative to the second arm in a latched mode, and when unlatched allows the first arm to move relative to the second arm in an unlatched mode. The system also employs a sensor attached to one of the arms that can detect when the arms are moving relative to each other, and adapted to provide a signal indicating the detected movement.

A valve used in combination with a vessel containing fluid in the interior and a parameter measuring device. The valve allows the device to be exposed to the fluid in the interior of the vessel. The device may be installed into the valve, and the valve may be fitted to the side of the vessel. The valve improves upon other prior art by providing provisions for purging air trapped in the internal cavity of the valve. The valve includes a purge position, which provides a smaller opening from the interior of the vessel to the internal cavity and an air path to the external atmosphere. Fluid may fill the valve pushing trapped air out of the valve until the majority of the trapped air is expelled.

Disclosed is an internal combustion engine including: an actuator for axial displacement of at least one gas exchange valve of the internal combustion engine, wherein the actuator includes: an actuator piston disc, a cylinder volume adapted for the actuator piston disc, wherein the actuator piston disc is movably arranged in an axial direction between a rest position and an active position, wherein the position sensor arrangement is configured for determining the position of the at least one gas exchange valve, the at least one gas exchange valve being displaced by the movement of the actuator piston disc, and a local control unit associated with the actuator, wherein the local control unit is operatively connected to the at least one controllable inlet valve and the controllable outlet valve of the actuator and operatively connected to the position sensor arrangement.

A method and position sensor assembly for determining a mutual position between a first object and a second object. The position sensor assembly includes a first body, a coil, a control unit, and a sensor circuit, the first body being reciprocally displaceable in the axial direction in relation to the coil. The sensor circuit includes in turn a comparator connected to a first branch including the coil, a power switch, and a measuring resistance coupled in series with each other.

A method for adjusting a valve lash in an internal combustion engine includes receiving a first signal generated by a sensor secured to the internal combustion engine, the first signal being indicative of a closing of a valve, receiving a second signal indicative of at least one of an engine speed of the internal combustion engine or a position of a camshaft of the internal combustion engine, and automatically determining an adjusted amount of lash associated with the valve based on the received first signal and the received second signal. The method also includes comparing the adjusted amount of lash to at least one predetermined threshold, and providing, in response to determining that the adjusted amount of lash is greater than the at least one predetermined threshold, a valve lash re-adjustment notification.

A method of operating an internal combustion engine having an electrical circuit that includes a connection closed by abutment between two distinct parts, one of which is mounted to a rocker arm of a rocker arm assembly and another that is mounted to a part distinct from the rocker arm. The connection is structured such that the movement of the rocker arm causes relative motion between the surfaces of the distinct parts that close the connection. The relative motion causes the circuit resistance to transition between values within a first range and values within a second range. The transitions of resistance between those ranges are detected and their presence, absence, or timing used for purposes of providing diagnostic feedback or control.

Disclosed is an internal combustion engine including: an actuator for axial displacement of at least one gas exchange valve of the internal combustion engine, wherein the actuator includes: an actuator piston disc, a cylinder volume adapted for the actuator piston disc, wherein the actuator piston disc is movably arranged in an axial direction between a rest position and an active position, wherein the position sensor arrangement is configured for determining the position of the at least one gas exchange valve, the at least one gas exchange valve being displaced by the movement of the actuator piston disc, and a local control unit associated with the actuator, wherein the local control unit is operatively connected to the at least one controllable inlet valve and the controllable outlet valve of the actuator and operatively connected to the position sensor arrangement.

A method for adjusting a valve lash in an internal combustion engine includes receiving a first signal generated by a sensor secured to the internal combustion engine, the first signal being indicative of a closing of a valve, receiving a second signal indicative of at least one of an engine speed of the internal combustion engine or a position of a camshaft of the internal combustion engine, and automatically determining an adjusted amount of lash associated with the valve based on the received first signal and the received second signal. The method also includes comparing the adjusted amount of lash to at least one predetermined threshold, and providing, in response to determining that the adjusted amount of lash is greater than the at least one predetermined threshold, a valve lash re-adjustment notification.