Lash adjuster

Abstract

In accordance with the present invention, a lash adjuster is provided for minimizing stress on a valve train system in the event of its failure. Specifically, the present invention lash adjuster is for use in a valve train system having a cam for actuating the opening and closing of a valve, where the cam has a select size and shape for determining the velocity or acceleration of the valve's opening and closing. The present invention lash adjuster generally comprises a housing having a base and a plunger positioned within the housing at a select axial clearance from the base. This clearance is generally sized and shaped such that, in the event of lash adjuster failure, a select maximum velocity or acceleration of valve opening and closing is maintained, thereby minimizing stress on the valve train system.

1 . A lash adjuster for use in a valve train system, said valve train system having a cam for actuating the opening and closing of at least one valve, wherein said cam has a select size and shape for determining the velocity of valve opening and closing, a member having a lash adjuster to maintain zero clearance between at least one valve tip and said member, said lash adjuster comprising,
 a housing having a base,   a plunger situated within said housing and being situated at a select axial clearance from the base of said housing, wherein the select axial clearance is sized and shaped such that in the event of lash adjuster failure, a select maximum velocity of valve opening and closing is maintained, thereby minimizing stress on the valve train system in the event of lash adjuster failure.   
     
     
         2 . The lash adjuster of  claim 1  wherein said member is a rocker arm. 
     
     
         3 . The lash adjuster of  claim 1  wherein said member is a valve bridge. 
     
     
         4 . The lash adjuster of  claim 1  wherein said member is a cam. 
     
     
         5 . The lash adjuster of  claim 1  further comprising a ball retainer for retaining a ball near the base of said housing. 
     
     
         6 . The lash adjuster of  claim 5 , wherein failure of said ball retainer results in lash adjuster failure. 
     
     
         7 . The lash adjuster of  claim 5  further comprising a ball spring for holding said ball against a seat in the base of said housing. 
     
     
         8 . The lash adjuster of  claim 7 , wherein failure of said spring results in lash adjuster failure. 
     
     
         9 . The lash adjuster of  claim 7 , wherein malfunction of the engagement between said ball and seat results in lash adjuster failure. 
     
     
         10 . The lash adjuster of  claim 1 , wherein the select axial clearance is sized to have a length of between about 0.01 inches and about 0.03 inches. 
     
     
         11 . The lash adjuster of  claim 1 , wherein the select axial clearance is sized to have a length of about 0.02 inches. 
     
     
         12 . The lash adjuster of  claim 1 , wherein the maximum velocity of valve opening is between about 5 inches per second and about 14.40 inches per second and the maximum velocity of valve closing is between about 15 inches per second and about 20 inches per second. 
     
     
         13 . The lash adjuster of  claim 1 , wherein the change in opening and closing velocities of the valve remain relatively gradual. 
     
     
         14 . A lash adjuster for use in a valve train system, said valve train system having a cam for actuating opening and closing of at least one valve, wherein said cam has a select size and shape for determining the acceleration of valve opening and closing, a member having a lash adjuster to maintain zero clearance between at least one valve tip and member, said lash adjuster comprising,
 a housing having a base,   a plunger situated within said housing and being situated at a select axial clearance from the base of said housing, wherein the select axial clearance is sized and shaped such that in the event of lash adjuster failure, a select maximum acceleration of valve opening and closing is maintained, thereby minimizing stress on the valve train system in the event of lash adjuster failure.   
     
     
         15 . The lash adjuster of  claim 14  wherein said member is a rocker arm. 
     
     
         16 . The lash adjuster of  claim 14  wherein said member is a valve bridge. 
     
     
         17 . The lash adjuster of  claim 14  wherein said member is a cam. 
     
     
         18 . The lash adjuster of  claim 14  further comprising a ball retainer for retaining a ball near the base of said housing. 
     
     
         19 . The lash adjuster of  claim 18 , wherein failure of said ball retainer results in lash adjuster failure. 
     
     
         20 . The lash adjuster of  claim 18  further comprising a ball spring for holding said ball against a seat in the base of said housing. 
     
     
         21 . The lash adjuster of  claim 20 , wherein failure of said spring results in lash adjuster failure. 
     
     
         22 . The lash adjuster of  claim 20 , wherein malfunction of the engagement between said ball and seat results in lash adjuster failure. 
     
     
         23 . The lash adjuster of  claim 14 , wherein the axial clearance is sized to have a length of between about 0.01 inches and about 0.03 inches. 
     
     
         24 . The lash adjuster of  claim 14 , wherein the axial clearance is sized to have a length of about 0.025 inches. 
     
     
         25 . The lash adjuster of  claim 18 , wherein the maximum acceleration of valve opening is about 78,000 inches/second 2  and the maximum acceleration of valve closing is about 107,700 inches/second 2 .