Shock absorber

Abstract

A shock absorber comprises first and second axially aligned cylinders ( 11, 21 ) each having a liquid filled piston chamber ( 12, 22 ), an axially displaceable piston ( 13, 23 ) received in the piston chamber ( 12, 22 ), and means ( 14, 24 ) for dampening axial displacement of the piston ( 13, 23 ) through the liquid in the piston chamber ( 12, 22 ). A piston rod ( 1 ) axially extends between and into the first and second cylinder piston chambers ( 12, 22 ). The first and second axial ends ( 1 a, 1 b ) of the piston rod ( 1 ) are connected to the first and second cylinder pistons ( 13, 23 ), respectively. In another form, the shock absorber comprises a single cylinder ( 111 ) with two piston ( 113, 123 ) and piston rod ( 101, 201 ) assemblies, one piston rod ( 101, 201 ) extending through each end ( 111 a, 111 b ) of the cylinder ( 111 ).

1 . A shock absorber comprising:
 a cylinder having a liquid filled piston chamber,   an axially displaceable piston received in said piston chamber,   means for dampening axial displacement of said piston through said liquid in said piston chamber,   a piston rod connected to said piston and extending through a first end of said cylinder,   a sleeve telescopically disposed about and sealingly engaging said cylinder and extending from said cylinder first end, a distal axial end of said sleeve being sealed such that said sleeve defines a sealed sleeve cavity, said piston rod being fixed in relation to said sleeve, and   means for securing one of said sleeve and said cylinder to a body of a vehicle and the other of said sleeve and said cylinder to a wheel suspension of a vehicle.   
   
   
       2 . The shock absorber of  claim 1  wherein said sleeve is provided with a valve means for adjusting gas pressure within said sleeve cavity. 
   
   
       3 . The shock absorber of  claim 1  wherein an annular cavity is defined in an overlap region between said cylinder and said sleeve, opposing axial ends of said annular cavity being respectively defined by a first seal means fixed to said cylinder and sealingly engaging said sleeve and a second seal means fixed to said sleeve and sealingly engaging said cylinder. 
   
   
       4 . The shock absorber of  claim 3  wherein said annular cavity communicates with said piston chamber, a cross sectional area of said annular cavity measured in a plane perpendicular to a longitudinal axis of said piston rod being substantially equal to a cross sectional area of said piston rod. 
   
   
       5 . The shock absorber of  claim 3  wherein said annular cavity is provided with a valve means for adjusting gas pressure therein. 
   
   
       6 . In combination, a first shock absorber according to  claim 3  and a second shock absorber according to claim  45  wherein said annular cavity of said first shock absorber is filled with liquid and is operatively associated with said sleeve cavity of said second shock absorber such that a decrease/increase in the volume of said annular cavity of said first shock absorber provides an increase/decrease in gas pressure in said sleeve cavity of said second shock absorber. 
   
   
       7 . The combination of  claim 6  wherein said annular cavity of said first shock absorber communicates with a first end of a control cylinder and said sleeve cavity of said second shock absorber communicates with a second end of said control cylinder, a control cylinder dividing piston being disposed within said control cylinder isolating said annular cavity of said first shock absorber and said sleeve cavity of said second shock absorber. 
   
   
       8 . The combination of  claim 7  wherein said control cylinder dividing piston is provided with a piston rod sealingly received in a reduced cross section portion of said control cylinder toward said control cylinder first end such that an extending end of said piston rod isolates said annular cavity of said first shock absorber. 
   
   
       9 . The combination of  claim 6  wherein said annular cavity of said second shock absorber is filled with liquid and is operatively associated with said sleeve cavity of said first shock absorber such that a decrease/increase in the volume of said annular cavity of said second shock absorber provides an increase/decrease in gas pressure in said sleeve cavity of said first shock absorber.