Engine valvetrain deactivation system with switchable rocker arm cam lift
AssigneeGM Global Technology Operations LLC
InventorsAnteo Carl Opipari, Paul Austin, Brian Joseph Warner, Rolando Huerta Ortiz
Life of this patent
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Abstract
A cylinder deactivation system for an engine includes an engine block defining a cylinder. A valve opens and closes a port to the cylinder. A rocker arm pivots to operate the valve. A camshaft has a cam lift and a cam-to-rocker input system transfers the cam lift through the rocker arm to the valve. A deactivation assembly is disposed in the rocker arm and is responsive to fluid pressure to alternately effect an activated state of the valve and a deactivated state of the valve.
Claims20
A cylinder deactivation system for an engine, the cylinder deactivation system comprising:
- an engine block defining a cylinder;
- a valve configured for opening and closing a port to the cylinder;
- a rocker arm including a cam input end and a valve end, the rocker arm configured to pivot about a point between the cam input end and the valve end so as to operate the valve;
- a camshaft including a cam lift;
- a cam effector configured to transfer the cam lift to the valve via the rocker arm;
- and
- a hydraulically-actuated deactivation assembly disposed in a bore formed at the cam input end of the rocker arm, the deactivation assembly configured to alternately effect an activated state of the valve and a deactivated state of the valve, wherein the deactivation assembly absorbs the cam lift such that the rocker arm does not pivot when in the deactivated state of the valve.
A cylinder deactivation system for an engine, the cylinder deactivation system comprising:
- an engine block defining a cylinder;
- a valve configured for opening and closing a port to the cylinder;
- a rocker arm including a cam input end and a valve end, the rocker arm configured to pivot about a point between the cam input end and the valve end so as to operate the valve;
- a camshaft including a cam lift;
- a cam effector configured to transfer the cam lift to the valve via the rocker arm;
- and
- a hydraulically-actuated deactivation assembly disposed in a bore formed at the cam input end of the rocker arm, the deactivation assembly including a lock pin configured to alternately lock and unlock the rocker arm from pivoting so as to respectively effect an activated state of the valve and a deactivated state of the valve,
- wherein the deactivation assembly absorbs the cam lift such that the rocker arm does not pivot when in the deactivated state of the valve.
A cylinder deactivation system for an engine, the cylinder deactivation system comprising:
- an engine block defining a cylinder;
- a valve configured for opening and closing a port to the cylinder;
- a rocker arm including a cam input end and a valve end, the rocker arm configured to pivot about a point between the cam input end and the valve end so as to operate the valve;
- a camshaft including a cam lift;
- a cam effector configured to transfer the cam lift to the valve via the rocker arm;
- and
- a hydraulically actuated deactivation assembly disposed in a bore formed at the cam input end of the rocker arm, the deactivation assembly including:
- a lock pin configured to alternately lock and unlock the rocker arm from pivoting so as to respectively effect an activated state of the valve and a deactivated state of the valve, and
- a deactivation spring disposed in the bore, the deactivation spring serving as a lost motion spring which absorbs the cam lift such that the rocker arm does not pivot and the valve does not open when in the deactivated state of the valve.
Dependencies are inferred from the claim text.