Shock absorber

Abstract

A shock absorber for a bicycle comprises a base, a clutch assembly, a control assembly and a shock-absorbing spring. The shock-absorbing spring provides damper elastic force for the respective components of the shock absorber. The shock-absorbing function can be turned off when riding up slope, so it prevents the drag force from being increased by the up and down motion of the shock absorber. The shock-absorbing function can be turned off when riding on a horizontal road, and it can be turned off again when riding down a slope, thus preventing the increase of the front tilt angle of the bike and leading to turnover.

1 . A shock absorber comprising a base, a clutch assembly, a control assembly and a shock-absorbing spring, the shock-absorbing spring providing damper elastic force for the respective components of the shock absorber, wherein: 
 the clutch assembly includes a positioning member, an axial tube, a clutch member and a control element, the positioning member is formed with the positioning grooves, the axial tube is formed with positioning holes, the positioning member and the axial tube are telescopically disposed, the clutch member is received in the positioning holes of the axial tube, the control element is formed with annular cone-shaped step portion that divides the control element into a big diameter portion and a small diameter portion, the big diameter portion and the small diameter portion serve to push the clutch member to move, motion of the clutch member can produce relative slide and engagement between the positioning member and the axial tube, through this way, the shock-absorbing function of the shock absorber can be turned on/off.    
   
   
       2 . The shock absorber as claimed in  claim 1 , wherein: 
 the base has a first end fixed to a body of a bike, and a second end of the base is received with a receiving tube, a first end of the receiving tube is moveably disposed in the base, and a second of the receiving tube is fixed at a corresponding position on the body of a bike, the receiving tube is able to move relative to the base;    the control assembly is positioned at an end of the receiving tube of the base;    the shock-absorbing spring is received in the base and biased between the control assembly and the base.    
   
   
       3 . The shock absorber as claimed in  claim 1 , wherein: 
 the control assembly includes a body, a control shaft, a control spring, a back-moving spring and an abutting member, the body is formed with a through hole for reception of an end of the control shaft, another end of the control shaft is formed with a plurality of driving threads for meshing with a plurality of driving threads at an end of the abutting member, another end of the abutting member serves to abut against the control element of the clutch assembly, the control shaft is under control of the steel cord, the steel cord is controlled by user, the user can rotate the control shaft by pulling the steel cord, the rotation of the shaft can enable the abutting member to move the control element of the clutch assembly, the back-moving spring serves to push the control shaft back to its original position, an end of the control spring is compressed and decompressed by the control shaft and serves to move the control element of the clutch assembly.