Push rod for rocker arm actuation
The present invention provides an improved push rod for actuating poppet valves in internal combustion engines. The improved push rod provides a vibration dampening beam member to alter push rod vibration frequency spectrum, levels and amplitude introduced through push rods to valve systems. Reducing push rod vibrations and amplitude improve valve system and engine performance.
This is a non-provisional application relating to and claiming the benefit of U.S. Provisional Patent Application Ser. No. 60/755,455, Filed Jan. 3, 2006.
BACKGROUND OF THE INVENTION1. Field of the Invention
The present invention relates to the field of internal combustion engines pertaining to poppet valve operating systems having rocker arms actuated by push rod and cam, particularly a push rod beam member providing means to dampen vibration by an elastomeric component and outer cover embodiments.
2. Description of Background Information
Internal combustion engines having poppet valve systems actuated by push rods that operate generally at high engine speed, or having aggressive valve actuation, commonly experience levels of induced vibration and dynamic motions in the valve system. Such vibrations adversely affect the valve system and engine performance. The primary dynamic responding members of the valve system assembly are the push rod, rocker arm, valve and valve spring assembly. These primary members as a consequence of high engine speed and aggressive valve actuation requirements initiate vibrations that transmit and reinforce and amplify dynamic forces affecting the valve system. The push rod and valve spring are arguably the principle members where vibrations and dynamic response need control improvement. The invention provides a means to control and dampen push rod vibration frequencies and force amplitude in the field of internal combustion engine poppet valve systems.
The push rod generally being a beam having a long slender tube shape momentarily deforms from cam acceleration rates as opening forces are required to overcome mass effects of the rocker arm, the valve and valve spring's closing force. Push rod deflecting conditions also reoccur on the closing cycle as the spring returns the components to the closed position with inertia force that deflects the push rod. These cyclical forces loading the push rod may occur at over 70 cycles per second on high-speed valve systems. Therefore on valve systems having aggressive valve lift rates, the initial opening inertia cycle force being high commonly deflects the push rod beam body inducing vibrations and dynamic force amplification to the push rod and valve system components. A means to dampen push rod vibrations and amplitudes embodying elastomeric component and rigid outer covering is disclosed.
SUMARY OF THE INVENTIONIn one form of the present invention there is provided a tubular push rod beam for opening and actuating poppet valves for internal combustion engines. A push rod is provided. A elastomeric component is bonded to the outer surface of the tubular push rod load carrying beam. In another form of the present invention a push rod is provided having an outer cover bonded to the elastomeric component. The push rod assembly includes at each end a ball-socket connection. First ball-socket registers in a socket of a separate system lifter that transmits opening forces actuated by the cam to the push rod. Second ball-socket registers at opposite push rod end to a connection at a separate rocker arm to open and close a poppet valve.
The elastomeric being bonded to the push rod tubular beam has prescribed thickness and elastomeric characteristics to provide dampening push rod vibrations. The outer cover provides added vibration dampening and deflection control by bonding to and incasing the elastomeric dampening medium. Reduction in vibration amplitude can be important, particularly at or near resonant frequencies. Vibration spectrum modification is an important objective. Resulting improvements in valve train dynamic behavior are sufficient to make notable engine performance improvement.
BRIEF DESCRIPTION OF THE DRAWINGSThe drawings constitute a part of this specification and include the embodiment of this invention.
In one specific embodiment of the present invention there is provided an improved push rod for actuation of rocker arms and poppet valve actuation for internal combustion engines. The improved system embodies a push rod having a vibration dampening elastomeric component bonded along the longitudinal length to the diameter of a tubular push rod.
In another specific embodiment of the present invention there is provided a push rod having a vibration dampening elastomeric component bonded along the longitudinal length having an added tubular outer component cover bonded to the elastomeric. The outer cover generally being thin metal tubing. The outer covering component is not limited to metal tubing; in certain applications materials such as high strength tape may be tensioned wrapped to provide resistive reaction to vibration force transmission. Embodiment of the cover provides a further means of absorbing vibration energy and amplitude.
A detailed description of a push rod poppet valve system is presented with reference to
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Manufacturing the push rod elastomeric is disclosed for one embodiment of the present specification that having push rod beam 10 and component 11. Referring to
Although preferred embodiments have been specified in the detailed description, there are system variations and combinations of the disclosed embodiments not shown that may be used. Combinations having beam tapering and elastomeric sections having varied hardness and dampening are applicable. The specified embodiments of the present invention are especially noted to be applicable to requirements of the general field of internal combustion engines and poppet valve operation.
Claims
1. A push rod system for internal combustion engines comprising:
- a push rod load carrying beam; a elastomeric component vulcanized to the beam; a first ball-socket connection at a first end utilized to connect a lifter means operated by an engine cam; a second ball-socket connection at the opposite end to connect to an engine rocker arm and valve assembly;
- said push rod beam being a axial load carrying member having tubular form of metal structure;
- said elastomeric component vulcanized bonded along the longitudinal beam length being a vibration absorbing component;
- said elastomeric being homogeneous texture component vulcanized bonded onto said beam member.
2. The system of claim 1 wherein said push rod beam has an outer tubular cover along the longitudinal length vulcanized bonded to inner elastomeric comprising;
- said outer cover being tubular and positioned longitudinally and concentric to said push rod beam member providing a cavity for a elastomeric component;
- said elastomeric being homogeneous texture component within a cavity vulcanized bonded to said push rod beam and to the outer cover.
Type: Application
Filed: Dec 29, 2006
Publication Date: Jul 5, 2007
Inventor: Cecil Stevens (Salisbury, NC)
Application Number: 11/647,845
International Classification: F01L 1/14 (20060101);