An oil passage switching valve suitable for a valve timing changing apparatus includes: a valve body, opening or closing an oil passage of operating oil; an urging spring, urging to position the valve body to a position corresponding to the retard position in a pause state; and a switching element, positioning the valve body to a position corresponding to the retard position when a state quantity of the operating oil is in a first range, and switching a position of the valve body in response to the state quantity (pressure or temperature) of the operating oil while resisting an urging force of the urging spring to position the valve body to a position corresponding to the advance position when the state quantity of the operating oil is in a second range greater than the first range.

A camshaft for a multi-cylinder internal combustion engine with poppet valves, comprising a main body, which is rotatable with respect to a first rotation axis, a first disk and means of the hydraulic type for varying the timing of said first disk with respect to said main body.

A camshaft for a multi-cylinder internal combustion engine with poppet valves, comprising a main body, which is rotatable with respect to a first rotation axis, a first disk and means of the hydraulic type for varying the timing of said first disk with respect to said main body.

An internal combustion engine, including a piston, a cylinder, and an output shaft, wherein the piston is arranged for reciprocating motion within the cylinder, driven by combustion, and the piston is coupled to the output shaft by a coupling such that said reciprocating motion of the piston drives rotation of the output shaft, wherein the coupling includes a connecting rod coupled to the piston, a slider bearing located for reciprocating movement relative to the connecting rod, the coupling further including a crankshaft rotatably mounted within a slider bearing, the engine having a camshaft and a balance shaft wherein the balance shaft is housed in a hollow of the camshaft such that the camshaft and the balance shaft rotate about a common axis.

An internal combustion engine, including a piston, a cylinder, and an output shaft, wherein the piston is arranged for reciprocating motion within the cylinder, driven by combustion, and the piston is coupled to the output shaft by a coupling such that said reciprocating motion of the piston drives rotation of the output shaft, wherein the coupling includes a connecting rod coupled to the piston, a slider bearing located for reciprocating movement relative to the connecting rod, the coupling further including a crankshaft rotatably mounted within a slider bearing, the engine having a camshaft and a balance shaft wherein the balance shaft is housed in a hollow of the camshaft such that the camshaft and the balance shaft rotate about a common axis.

An apparatus is provided to test valves. The apparatus includes a support structure and a plurality of engagement members coupled to the support structure. Each member of the plurality of engagement members is coupled with a valve of a valve train associated with an engine head. The apparatus further includes a camshaft, which includes a plurality of lobes coupled to the support structure. Each lobe of the plurality of lobes are equally spaced from each other and coupled to a member of the plurality of engagement members. The apparatus further includes a driving mechanism coupled to the camshaft, which is configured to rotate the camshaft and control each member of the plurality of engagement members to further control an activation of each valve of the valve train associated with the engine head.

An apparatus is provided to test valves. The apparatus includes a sensor and a driving mechanism. The driving mechanism is configured to control an external camshaft that is coupled to a valve train of an engine head. The apparatus controls the driving mechanism to control a rotation of the external camshaft that further controls an activation of each valve of the valve train associated with the engine head. The apparatus further controls the sensor to acquire information associated with the activation of each valve of the valve train based on the rotation of the external camshaft. The apparatus further compares the acquired information with pre-stored information, to determine an abnormality in each valve of the valve train, and generates a notification based on the comparison.

An apparatus is provided to test valves. The apparatus includes a sensor and a driving mechanism. The driving mechanism is configured to control an external camshaft that is coupled to a valve train of an engine head. The apparatus controls the driving mechanism to control a rotation of the external camshaft that further controls an activation of each valve of the valve train associated with the engine head. The apparatus further controls the sensor to acquire information associated with the activation of each valve of the valve train based on the rotation of the external camshaft. The apparatus further compares the acquired information with pre-stored information, to determine an abnormality in each valve of the valve train, and generates a notification based on the comparison.

A camshaft assembly for a vehicle valvetrain having first and second engine valves includes a camshaft, and a first camshaft cartridge axially displaceable along the camshaft and including a plurality of first cam lobes configured to selectively impart movement to the first engine valve. A second camshaft cartridge is axially displaceable along the camshaft and includes a plurality of second cam lobes configured to selectively impart movement to the second engine valve. An actuator is configured to axially displace the first camshaft cartridge along the camshaft. A coupling is between the first camshaft cartridge and the second camshaft cartridge. Axial displacement of the first camshaft cartridge selectively imparts movement to the second camshaft cartridge for axial displacement of the second camshaft cartridge.

A camshaft assembly for a vehicle valvetrain having first and second engine valves includes a camshaft, and a first camshaft cartridge axially displaceable along the camshaft and including a plurality of first cam lobes configured to selectively impart movement to the first engine valve. A second camshaft cartridge is axially displaceable along the camshaft and includes a plurality of second cam lobes configured to selectively impart movement to the second engine valve. An actuator is configured to axially displace the first camshaft cartridge along the camshaft. A coupling is between the first camshaft cartridge and the second camshaft cartridge. Axial displacement of the first camshaft cartridge selectively imparts movement to the second camshaft cartridge for axial displacement of the second camshaft cartridge.