Back to results
US 4,132,395 AGranted
Shock absorber with improved extension damping
OwnerRobert C. Fox, Jr.inventor
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
OwnerRobert C. Fox, Jr.inventor
Estimating the term…
A shock absorber, particularly adapted for use in the rear suspension of a motorcycle, comprises a tubular housing having a piston reciprocally mounted therein. A first chamber is defined between the housing and the head end of the piston whereas a second chamber is defined between the rod end of the piston and the housing. An inflatable bladder is disposed in a hollow rod of the piston and defines the third chamber with the rod which is in open communication with the first chamber. The chambers are at least partially filled with oil and the first chamber and bladder are air-pressurized to selectively set the spring rates of the shock absorber. A plurality of circumferentially disposed ports are formed through a head of the piston and are normally closed by a spring washer to prevent communication of oil from the first chamber to the second chamber upon extension of the shock absorber and for permitting such communication upon compression thereof. An orifice is also formed through the head of the piston to meter oil from the second chamber to the first chamber upon extension of the shock absorber. A check valve is also mounted in the head to cooperate with the orifice to also meter fluid from the second chamber to the first chamber upon extension of the shock absorber and when the differential pressure of the oil between the first and second chambers exceeds a predetermined level.
In a shock absorber adapted for use on motorcycles and the like comprising a tubular housing, a piston reciprocally mounted in said housing and having a ring mounted on a head thereof to define first and second chambers between said head and said housing on either side of said head retaining oil therein, first check valve means for introducing air into said first chamber for pressurizing said first chamber an inflated bladder, defining a closed chamber therein adapted to be filled with air, disposed in a hollow rod of said piston and defining a third chamber between said bladder and said piston in open communication with said first chamber, second check valve means for introducing air into said closed chamber for pressurizing the closed chamber, a continuously open orifice means formed through said head to meter said oil from said second chamber to said first chamber upon extension of said shock absorber, the improvement comprising check valve means mounted in said head at a position thereon separated from said orifice means for preventing communication of said oil from said first chamber to said second chamber upon compression of said shock absorber and for cooperating with said orifice means to open to also meter said oil from said second chamber to said first chamber at a controlled rate upon extension of said shock absorber and when the differential pressure of said oil between said first and second chambers exceeds a predetermined level.
Dependencies are inferred from the claim text.