Structure of piston for hydraulic shock absorber

Abstract

A piston rod insert axis portion 3 is provided in a top end of a piston rod 2 entering into and going out from a cylinder 1 , a piston 4 is inserted into the piston rod insert axis portion 3 , and the piston 4 , as well as damping valves 6 and 7 similarly inserted into the piston rod insert axis portion 3 are clamped and fixed by a nut 8 . The piston rod insert axis portion 3 is formed separately from the piston rod 2 , as well as the piston rod insert axis portion 3 and the a base end of the piston rod 2 are connected by a screw bore 11 and a screw shaft 12 as fixation members.

1 . A hydraulic shock absorber provided with a cylinder, a piston sliding in the cylinder, and a piston rod to a top end of which the piston is connected, comprising: 
 a piston rod insert axis portion formed separately from the piston rod;    a damping valve inserted and fixed in the piston rod insert axis portion together with the piston; and    a combination member combining the piston rod insert axis portion with the top end of the piston rod.    
   
   
       2 . The hydraulic shock absorber according to  claim 1 , wherein: 
 an expansion-side port and a compression-side port are formed in the piston; and    the damping valve includes an expansion-side damping valve arranged in one face of the piston to open/close the expansion-side port and a compression-side damping valve arranged in the other face of the piston to open/close the compression-side port.    
   
   
       3 . The hydraulic shock absorber according to  claim 2 , wherein: 
 the combination member includes; 
 a screw bore provided in the top end of the piston rod, and  
 a screw shaft provided in the piston rod insert axis portion to be screwed into the screw bore.  
   
   
   
       4 . The hydraulic shock absorber according to  claim 3 , wherein: 
 the piston rod insert axis portion is provided with an engagement member positioned at a halfway of the piston rod insert axis portion, and a screw portion positioned at a top end of the piston rod insert axis portion, the hydraulic shock absorber further comprising:    a piston nut screwed into the screw portion to clamp and fix the piston and the damping valve between the piston nut and the engagement member.    
   
   
       5 . The hydraulic shock absorber according to  claim 4 , wherein: 
 the engagement member is screwed into the piston rod insert axis portion.    
   
   
       6 . The hydraulic shock absorber according to  claim 3 , wherein: 
 the piston rod insert axis portion is provided with a screw portion, the hydraulic shock absorber further comprising:    a piston nut screwed into the screw portion, wherein:    the piston and the damping valve are clamped and fixed between the piston nut and the top end of the piston rod.    
   
   
       7 . The hydraulic shock absorber according to  claim 3 , further comprising: 
 a piston nut formed integrally with an end of the piston rod insert axis portion, wherein:    the piston and the damping valve are clamped and fixed between the piston nut and the top end of the piston rod.