Shock absorber including valved bypass

Claim 1

A shock absorber comprising, in combination: a. a cylinder member having an axis and defining a cavity therein, said cylinder member having an end wall axially bounding said cavity; b. a piston rod member sealingly received in said end wall for axial movement and having respective terminal portions in said cavity and outside said cylinder member; c. a piston slidably received in said cavity and fastened to one of said terminal portions, said piston axially dividing said cavity into two compartments and being formed with a throttling passage connecting said compartments; d. a tubular shell substantially coaxial with said cylinder member, 1. said shell and said cylinder member radially bounding a compensating chamber therebetween; e. an annular plate member interposed between said cylinder member and said shell member and axially bounding said chamber, 1. said plate member being formed with a throttling conduit connecting said chamber with said cavity, 2. said conduit having a flow section substantially smaller than the respective flow sections of adjacent portions of said cavity and of said chamber; f. fluid under a pressure higher than atmospheric pressure filling said cavity, said chamber, and said conduit; g. valve means for varying the flow section of said conduit; and h. valve control means responsive to the pressure of said fluid in said chamber for operating said valve means, said valve control means including 1. a control chamber, 2. a flexible diaphragm dividing said control chamber into two portions, one of said portions communicating with said compensating chamber and being filled with said fluid, the other one of said portions being sealed, 3. pressure means in said other portion for counteracting the pressure of said fluid on said diaphragm in said one portion, and 4. motion transmitting means connecting said diaphragm with said valve means.