Patent · US Expired

Damping force adjustable hydraulic shock absorber

US4953671A · kind A · utility

59Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 10, 1989
Grant dateSep 4, 1990
Priority date
Expiry dateAug 10, 2009

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60G2500/30
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic shock absorber is used, for example, in a vehicle, wherein the level of damping force is adjustable in accordance with the road surface conditions or the like during operation of the vehicle. The hydraulic shock absorber includes a piston attached to one end of a piston rod and slidably fitted in a cylinder, the piston dividing the interior of the cylinder into two cylinder chambers. A passage is provided in the piston, the passage communicating with each of the two cylinder chambers. A damping force generating valve is provided at the downstream side of the passage to generate damping force. A back-pressure chamber is formed at the side of the damping force generating valve which is remote from the piston to apply pressure to the valve. A bypass passage is formed in the piston rod to provide communication between the back-pressure chamber and the upstream cylinder chamber that is provided at the upstream side of the passage. A shutter is externally operable to control the condition of communication between the upstream cylinder chamber and the back-pressure chamber, thereby adjusting the level of pressure inside the back-pressure chamber. Thus, it is possible to obtain…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.