Internal-combustion engines – Poppet valve operating mechanism – Plural valve trains – single actuator
Reexamination Certificate
1999-05-06
2001-07-10
Denion, Thomas (Department: 3748)
Internal-combustion engines
Poppet valve operating mechanism
Plural valve trains, single actuator
C123S090400, C123S090610
Reexamination Certificate
active
06257187
ABSTRACT:
TECHNICAL FIELD
The present invention relates to internal combustion engines, and, more particularly, to internal combustion engines including a lever lifter assembly carried by a pivot shaft.
BACKGROUND ART
Internal combustion engines typically include a plurality of combustion cylinders. In an internal combustion engine with a V-block configuration, a housing includes a plurality of combustion cylinders in a first bank of combustion cylinders which are disposed at an acute angle relative to a plurality of combustion cylinders in a second bank of combustion cylinders. Each of the combustion cylinders typically includes a plurality of valves associated therewith which are actuated using push rods. The push rods are attached with lever lifters, with each lever lifter having a roller follower which engages a cam on a camshaft.
With a conventional V-block configuration, two pivot shafts are provided which respectively correspond to the first bank of combustion cylinders and the second bank of combustion cylinders. Lever lifter assemblies associated with the first bank of combustion cylinders are pivotally carried by one of the pivot shafts, and lever lifter assemblies associated with the second bank of combustion cylinders are pivotally carried by the other pivot shaft.
The problem with an internal combustion engine having a V-block configuration as described above is that two separate pivot shafts are used to carry the lever lifter assembly associated with the two different banks of combustion cylinders. The use of two different pivot shafts complicates and increases the cost of the assembly process during manufacture of the internal combustion engine. Moreover, the use of two pivot shafts requires additional space within the internal combustion engine not only for the pivot shafts, but also for the range of motion of the lever lifter assemblies carried by each pivot shaft. Thus, the package size of the internal combustion engine is also increased.
The present invention is directed to overcoming one or more of the problems as set forth above.
DISCLOSURE OF THE INVENTION
In one aspect of the invention, an internal combustion engine includes a housing with a plurality of combustion cylinders. At least one of the combustion cylinders has a longitudinal axis which is disposed at an acute angle relative to a longitudinal axis of at least one other combustion cylinder. A camshaft is rotatably carried by the housing and includes a plurality of cams. A plurality of lever lifter assemblies are associated with respective ones of the combustion cylinders. Each lever lifter assembly includes an intake lever lifter, an exhaust lever lifter and a fuel injector lever lifter. Each intake lever lifter, exhaust lever lifter and fuel injector lever lifter has a roller follower engaging a respective cam. A pivot shaft carried by the housing pivotally carries at least one lever lifter assembly associated with the at least one combustion cylinder and also pivotally carries at least one lever lifter assembly associated with the at least one other combustion cylinder.
In another aspect of the invention, an internal combustion engine is assembled. A housing is provided with a plurality of combustion cylinders. At least one of the combustion cylinders has a longitudinal axis which is disposed at an acute angle relative to a longitudinal axis of at least one other combustion cylinder. A camshaft is placed within and attached to the housing. The camshaft includes a plurality of cams. A plurality of lever lifter assemblies are slid over a pivot shaft. Each lever lifter assembly is associated with a respective one of the combustion cylinders, and includes an intake lever lifter, an exhaust lever lifter and a fuel injector lever lifter. The pivot shaft pivotally carries at least one lever lifter assembly associated with at least one combustion cylinder and also pivotally carries at least one lever lifter assembly associated with at least one other combustion cylinder. The pivot shaft is positioned within and attached to the housing, whereby a roller follower of each intake lever lifter, exhaust lever lifter and fuel injector lever lifter engages a respective cam.
REFERENCES:
patent: 2996050 (1961-08-01), Caris
patent: 3841280 (1974-10-01), Lussier
patent: 3884199 (1975-05-01), Irimajiri et al.
patent: 3930471 (1976-01-01), Leonard et al.
patent: 4206734 (1980-06-01), Perr et al.
patent: 4425881 (1984-01-01), Lyndhurst
patent: 4662322 (1987-05-01), Tamba et al.
patent: 4864983 (1989-09-01), Breitbarth
patent: 5347965 (1994-09-01), Decuir
patent: 5394843 (1995-03-01), Decuir
Caterpillar Inc.
Denion Thomas
Nguyen Tu M.
Taylor Todd T.
LandOfFree
Pivot shaft for an internal combustion engine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pivot shaft for an internal combustion engine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pivot shaft for an internal combustion engine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2527102