Vehicle Shock Absorber

Abstract

A vehicle shock absorber has a body extending between a first end and a second end. Translation of a primary shaft within an interior cavity of the body communicates a first volume of fluid within the interior cavity to a secondary reservoir where it increases pressure in a gas cavity therein. The primary shaft has an annular member engaged thereon which contacts a bump shaft slidably located in an opening at the first end of the body. The contact of the annular member translates the bump shaft within the interior cavity to cause communication of a secondary volume of the fluid to the secondary reservoir.

What is claimed is: 
     
         1 . A vehicle shock absorber comprising:
 a body having a first end and a second end;   an interior cavity running axially within said body in between an opening at said first end and said second end opposite said first end;   a bump shaft in a sealed engagement within said opening, said bump shaft having an extending portion projecting a distance away from said opening to a first end of said bump shaft;   said bump shaft having a second end positioned within said interior cavity;   said bump shaft having a passage therethrough running coaxial to said interior cavity;   a primary shaft in a translating engagement through said passage, said primary shaft having a first end opposite a second end;   a valved seal located at said second end of said primary shaft, said valved seal being in sealed engagement with a wall surface of said interior cavity;   said interior cavity in-between said valved seal and said second end of said body defining a compression chamber;   said interior cavity in-between said valved seal and said second end of said bump shaft defining a rebound chamber;   said compression chamber and said rebound chamber both having fluid therein;   a secondary reservoir having a first end and a second end and having an axial chamber therein;   said axial chamber having a dividing piston in sealed engagement therein;   a first portion of said axial chamber between said first end of said secondary reservoir and a first side surface of said dividing piston defining a fluid chamber;   said fluid chamber being filled with said fluid;   a second portion of said axial chamber positioned between a second side surface of said dividing piston and said second end of said secondary reservoir defining a gas cavity;   said gas cavity filled with gas;   a passage communicating between said compression chamber and said fluid chamber;   a translation of said primary shaft toward said second end of said body communicating a first volume of said fluid within said compression chamber through said passage into said fluid chamber;   communication of said first volume of said fluid to said fluid chamber generating a first force to translate said dividing piston toward said second end of said fluid reservoir to thereby cause a first increase in gas pressure in said gas within said gas cavity; and   whereby said first increase in pressure in said gas biases said dividing piston toward said first end of said secondary reservoir and impart a piston force to said fluid within said fluid chamber to thereby force said first volume of said fluid to return to said compression chamber.   
     
     
         2 . The vehicle shock absorber of  claim 1 , additionally comprising:
 said bump shaft in a sealed engagement within said opening being translatable therein from a first position with said extending portion projecting said distance away from said opening, so a second position having said first end of said bump shaft at or adjacent said opening;   an annular member engaged to said primary shaft at a position thereon in-between said opening and said first end thereof;   said translation of said primary shaft toward said second end of said body causing a contact of said annular member against said first end of said bump shaft;   said contact of said annular member with said first end of said bump shaft imparting a translation of said bump shaft toward said second end of said body;   said translation of said bump shaft communicating a second volume of said fluid through said passage into said fluid chamber;   said communication of said second volume of said fluid in combination with said first volume of said fluid communicated to said fluid chamber generating an increased said force to translate said dividing piston toward said second end of said fluid reservoir to thereby cause a secondary increase in pressure in said gas within said gas cavity; and   said first increase in pressure and said secondary increase in pressure combining to bias said gas against said dividing piston toward said first end of said secondary reservoir and thereby impart a combined piston force of the sum of said first increase in pressure and said secondary increase in pressure to force said first volume of said fluid and said secondary volume of said fluid to return to said compression chamber.   
     
     
         3 . The vehicle shock absorber of  claim 1 , additionally comprising:
 a compression fluid circuit communicating fluid between said compression chamber and said rebound chamber during said translation of said primary shaft toward said second end of said body;   a rebound fluid circuit communicating fluid between said rebound chamber and said compression chamber during a secondary translation of said primary shaft in a direction toward said first end of said body;   a first rate of fluid flowing through said compression fluid circuit imparting a dampening of movement of said primary shaft during said translation thereof toward said second end; and   a second rate of fluid flowing through said rebound fluid circuit imparting a dampening of movement of said primary shaft during said translation thereof toward said first end of said body.   
     
     
         4 . The vehicle shock absorber of  claim 2 , additionally comprising:
 a compression fluid circuit communicating fluid between said compression chamber and said rebound chamber during said translation of said primary shaft toward said second end of said body;   a rebound fluid circuit communicating fluid between said rebound chamber and said compression chamber during a secondary translation of said primary shaft in a direction toward said first end of said body;   a first rate of fluid flowing through said compression fluid circuit imparting a dampening of movement of said primary shaft during said translation thereof toward said second end; and   a second rate of fluid flowing through said rebound fluid circuit imparting a dampening of movement of said primary shaft during said translation thereof toward said first end of said body.   
     
     
         5 . The vehicle shock absorber of  claim 3 , additionally comprising:
 a compression valve engaged with said compression fluid circuit, said compression valve controlling a volume of said fluid communicating through said compression circuit; and   a rebound valve engaged with said rebound fluid circuit, said rebound valve controlling a volume of said fluid communicating through said rebound circuit.   
     
     
         6 . The vehicle shock absorber of  claim 4 , additionally comprising:
 a compression valve engaged with said compression fluid circuit, said compression valve controlling a volume of said fluid communicating through said compression circuit; and   a rebound valve engaged with said rebound fluid circuit, said rebound valve controlling a volume of said fluid communicating through said rebound circuit.