Switchable dual lifter
View Patent ↗The switchable dual lifter has two hydraulic lash adjusters, one which is fixed within the common housing, and the other which is movable to allow for deactivation of one of the two valves acted on by the dual lifter. Using the dual lifter with a switchable hydraulic lash adjuster allows for closing of one of the adjacent valves while allowing the other of the adjacent valves to operate.
1. A dual lifter for two adjacent valves in a cylinder of an internal combustion engine,
comprising:
a common elongated housing;
a cam contact member mounted at one end of said housing;
a first axial bore in said housing, having one end adjacent said one end of said housing and the other end open;
a second axial bore in said housing, having one end adjacent said one end of said housing and the other end open;
a first hydraulic lash adjuster mounted in said first axial bore, one end of said first lash adjuster adapted to contact a push-rod of one of two adjacent valves;
a second hydraulic lash adjuster movably mounted in said second axial bore, said second lash adjuster having one end adapted to contact a push-rod of the other of the two adjacent valves;
a locking member positioned at the other end of said second hydraulic lash adjuster for selectively locking the second hydraulic lash adjuster together with said housing for coincidental, reciprocal movement with said housing; and
a lost motion spring positioned between said locking member and said one end of said second axial bore so as to allow said second hydraulic lash adjuster to move when said locking member is unlocked.
2. The lifter of claim 1 wherein said locking member comprises pistons which are pushed radially outward by a spring into ports which are in the side wall of the second axial bore.
3. The lifter of claim 1 wherein a sleeve extends upward from said second axial bore, said sleeve having an internal opening concentric to and equal in diameter to said second axial bore.
4. The lifter of claim 1 wherein said housing is cylindrical.
5. The lifter of claim 1 wherein said housing has a first oil inlet for said first hydraulic lash adjuster, a second oil inlet for said second lash adjuster and said first oil inlet and said second oil inlet are connected by a channel.
6. The lifter of claim 1 wherein said first hydraulic lash adjuster is a switchable hydraulic lash adjuster.