Abstract:
Compact valve lifters are disclosed for overhead camshaft engines with direct acting valve gear and for engines with indirect acting valve actuation such as push rod actuated overhead valves. Two step variable lift and non-variable lift valve lifters are included as are roller and non-roller follower types with various features in common.
Abstract:
A valve-deactivation hydraulic valve lifter including a recessed face on the pin housing for making contact with the a crowned surface region of a roller follower. The lifter includes a pin housing that is slidably disposed within an axial bore in a lifter body. Pins for variably locking the pin housing to the lifter body may be disengaged to place the lifter in lost-motion mode by application of engine oil to the outer ends of the pins. A surface of the pin housing, preferably configured as a dished surface, is formed on the bottom end face of the pin housing that approaches the cam-following lifter roller for making contact with the roller follower so as to avoid contacting the roller follower's crowned surface region.
Abstract:
A deactivation valve lifter includes a lifter body. The lifter body has a first end configured for engaging a cam of an engine and at least one annular pin chamber. A pin housing includes a pin housing bottom. The pin housing bottom defines at least one pin stop aperture and a radially directed pin bore. A deactivation pin assembly is disposed within the pin bore and includes pin members. The pin housing is concentrically disposed within the lifter body. A portion of each pin member may be disposed within the annular pin chamber to thereby selectively couple and decouple the lifter body to the pin housing. A drain aperture defined by the pin housing bottom extends from the pin bore to an outside surface of the pin housing. A stop pin is disposed in the at least one pin stop aperture for limiting the inward motion of the pin members.
Abstract:
A valve lifter assembly for deactivating a cylinder in an internal combustion engine. The valve lifter assembly is provided with a plunger movably disposed within a bore of a main body member to controllably isolate the cam lift from the rocker arm and valve of the engine. The plunger is normally locked in an extended position to transmit cam lift to reciprocatingly operate the valve. At least one locking pin is moveably disposed within the plunger to engage an inner annular groove of the main body member. Pressurized oil is provided to dislodge the locking pins from the annular groove and allow the plunger to move within the main body member, thereby isolating the cam lift from the rocker arm and valve. The deactivating lifter is preferably disposed within the recess conventionally provided for hydraulic valve lifters.
Abstract:
An anti-rotation guide for a deactivation hydraulic valve lifter for an internal combustion engine. The guide includes a through bore accommodating of a hydraulic valve lifter and is sized such that the outer end of the lifter may be inserted into the through bore of the guide. The guide is securable to the engine such that the lifter is reciprocable within the guide. The guide is provided with two opposing keepers for mating with corresponding flats on the lifter to prevent rotation of the lifter. Further, a keyway means is provided in the guide and lifter to prevent the lifter being inserted into the guide 180° from the correct orientation.
Abstract:
Compact valve lifters are disclosed for overhead camshaft engines with direct acting valve gear and for engines with indirect acting valve actuation such as push rod actuated overhead valves. Two step variable lift and non-variable lift valve lifters are included as are roller and non-roller follower types with various features in common.
Abstract:
A camshaft has, for each valve lifter, a high lift cam between two low lift cams, the high lift cam fitting within the envelope of the low lift cams. The lifter comprises an outer tappet elongated in the direction of the camshaft and slidably mounted in an elongated bore in a cam carrier. The outer tappet is contacted by both low lift cams and operates two valves simultaneously. An elongated bore extending transverse of the outer tappet carries an elongated inner tappet which is contacted by the high lift cam. A hydraulically actuated locking mechanism couples the tappets for movement together for high lift operation and unlocks for low lift operation to allow the inner tappet to idle in the outer tappet.
Abstract:
A deactivation valve lifter includes a lifter body. The lifter body has a first end configured for engaging a cam of an engine and at least one annular pin chamber. A pin housing includes a pin housing bottom. The pin housing bottom defines at least one pin stop aperture and a radially directed pin bore. A deactivation pin assembly is disposed within the pin bore and includes pin members. The pin housing is concentrically disposed within the lifter body. A portion of each pin member may be disposed within the annular pin chamber to thereby selectively couple and decouple the lifter body to the pin housing. A drain aperture defined by the pin housing bottom extends from the pin bore to an outside surface of the pin housing. A stop pin is disposed in the at least one pin stop aperture for limiting the inward motion of the pin members.
Abstract:
A deactivation valve lifter includes a lifter body. The lifter body has a first end configured for engaging a cam of an engine and at least one annular pin chamber. A pin housing includes a pin housing bottom. The pin housing bottom defines at least one pin stop aperture and a radially directed pin bore. A deactivation pin assembly is disposed within the pin bore and includes pin members. The pin housing is concentrically disposed within the lifter body. A portion of each pin member may be disposed within the annular pin chamber to thereby selectively couple and decouple the lifter body to the pin housing. A drain aperture defined by the pin housing bottom extends from the pin bore to an outside surface of the pin housing. A stop pin is disposed in the at least one pin stop aperture for limiting the inward motion of the pin members.
Abstract:
An oil distribution system for an internal combustion engine comprising a longitudinal bore in the engine head or block connected to an engine oil pump. A longitudinal insert is disposed in the engine bore, the insert being formed and disposed to define segmented galleries within the bore, a first oil gallery being in communication with the engine camshaft bearings and a second oil gallery being in communication with switchable cam followers in the engine. The two galleries are separated but connected by one or more oil control valves. Thus, the camshaft bearings are exposed to high engine oil pressure at all times independent of the switchable cam followers; likewise, the switchable cam followers may be latched and unlatched at any time or condition deemed beneficial for engine operation without jeopardizing lubrication sufficiency to the camshaft bearings.