Hydraulic suspension unit

Claim 2

A load-leveling hydraulic suspension unit of the type having: a fluid reservoir; a high-pressure chamber; a telescopic member extensible from and retractable into the high-pressure chamber; a hydraulic retracting surface area defined of the telescopic member; means for pumping a fluid from the fluid reservoir to the highpressure chamber and increasing fluid pressure in the highpressure chamber to hydraulically react the fluid against the surface area and extend the telescopic member to a predetermined position; and means for returning fluid from the high-pressure chamber to the fluid reservoir when the telescopic member extends beyond a predetermined position; wherein the improvement comprises: a fluid pressure-regulating chamber fluidically communicable with the high-pressure chamber; piston means disposed within said fluid chamber for varying the volume thereof, said piston means defining a hydraulic reacting surface area which is greater than the hydraulic reacting surface area defined of the telescopic member; and spring means for biasing said piston means toward reducing the volume of said pressure-regulating chamber; whereby the ratio of the two hydraulic reacting surface areas is determinative of the spring rate transferable from said spring means to the telescopic member.

Claim 3

An improved hydraulic control circuit for a load-leveling hydraulic suspension unit, the circuit fillable with a fluid and of the type having: a fluid reservoir; a fluid receiving high-pressure chamber; a telescopic member extensible from and retractable into the high-pressure chamber; a hydraulic reacting surface area defined of the telescopic member; means for pumping fluid from the fluid reservoir to the high-pressure chamber and increasing fluid pressure in the high-pressure chamber to hydraulically react the fluid against the surface area and extend the telescopic member to a predetermined position; and means for returning fluid from the high-pressure chamber to the fluid reservoir when the telescopic member extends beyond a predetermined position; wherein the improvement comprises: a fluid pressure-regulating chamber hydraulically communicable with the high-pressure chamber; piston means disposed within the pressure-regulating chamber for varying the volume thereof, said piston means defining a hydraulic reacting surface area greater than the hydraulic reacting surface area of the telescopic member; and spring means for biasing said piston means toward reducing the volume of said pressure-regulating chamber; whereby the ratio of the two hydraulic reacting surface areas is determinative of the force hydraulically transferred from said piston means to the telescopic member.

Claim 4

An improved hydraulic control circuit for a load-leveling hydraulic suspension unit, the circuit fillable with a fluid and of the type having: a fluid reservoir; a fluid receiving high-pressure chamber; a telescopic member extensible from and retractable into the high-pressure chamber; a hydraulic reacting surface area defined of the telescopic member; means for pumping fluid from the fluid reservoir to the high-pressure chamber and increasing fluid pressure in the high-pressure chamber to hydraulically react the fluid against the surface area and extend the telescopic member to a predetermined position; and means for returning fluid from the high-pressure chamber to the fluid reservoir when the telescopic member extends beyond a predetermined position; wherein the improvement comprises: a fluid pressure-regulating chamber hydraulically communicable with the high-pressure chamber; piston means disposed within the pressure-regulating chamber for varying the volume thereof, said piston means defining a hydraulic reacting surface area greater than the hydraulic reacting surface area of the telescopic member; and spring means for biasing said piston means toward reducing the volume of said pressure-regulating chamber; whereby the ratio of the two hydraulic reacting surface areas is determinative of the force hydraulically transferred from said piston means to the telescopic member.

Claim 5

In the method of simultaneously providing damping, springing and load-leveling forces to a telescopic member of a hydraulic suspension unit as activated by jounce and rebound movements which activate a hydraulic control circuit by the method of: a. pumping a hydraulic fluid from a fluid reservoir to a high-pressure chamber with a pumping means activated by jounce and rebound movements; b. increasing the fluid energy level in the high-pressure chamber with the pumping means; c. damping the reciprocating movement of the telescopic member protruding from and reciprocating in the high-pressure chamber; d. reacting a surface area of the telescopic member reciprocating in the high-pressure chamber, with high-energy fluid to extend the extremity; e. deactivating the pumping means when the telescopic member is extended a predetermined amount; f. decreasing the fluid energy in the high-pressure chamber by bleeding fluid from the high-pressure chamber to the fluid reservoir when the telescopic member extends beyond a predetermined position; the improvement comprises simultaneously with step (d), the step of: regulating the fluid energy in the high-pressure chamber during jounce and rebound movements by hydraulically reacting the high-energy fluid in the high-pressure chamber against a spring biased piston having a hydraulic surface reacting area greater than the hydraulic reacting surface area of the telescopic member.

Claim 6

In the method of simultaneously providing damping, springing and load-leveling forces to a telescopic member of a hydraulic suspension unit as activated by jounce and rebound movements which activate a hydraulic control circuit by the method of: a. pumping a hydraulic fluid from a fluid reservoir to a high-pressure chamber with a pumping means activated by jounce and rebound movements; b. increasing the fluid energy level in the high-pressure chamber with the pumping means; c. damping the reciprocating movement of the telescopic member protruding from and reciprocating in the high-pressure chamber; d. reacting a surface area of the telescopic member reciprocating in the high-pressure chamber, with high-energy fluid to extend the extremity; e. deactivating the pumping means when the telescopic member is extended a predetermined amount; f. decreasing the fluid energy in the high-pressure chamber by bleeding fluid from the high-pressure chamber to the fluid reservoir when the telescopic member extends beyond a predetermined position; the improvement comprises simultaneously with step (d), the step of: regulating the fluid energy in the high-pressure chamber during jounce and rebound movements by hydraulically reacting the high-energy fluid in the high-pressure chamber against a spring biased piston having a hydraulic surface reacting area greater than the hydraulic reacting surface area of the telescopic member.