Parker-Hannifin Corporation

Commercial Intertech Limited

David John Anderson

Paul Kubinski

Timothy B Sweeney

Jason Danner

A check seat assembly includes a check valve seat with a by-pass passage in parallel with a check valve passage of the check seat assembly to meter flow and maintain stability of a hydraulic system, such as a hydraulic cylinder. The check valve may include an o-ring seated in a V-shaped groove. The check seat assembly may allow flow from a pump to a hydraulic cylinder to freely pass through the check valve to pressurize one side of a piston of the hydraulic cylinder, such as a front side of the piston to retract a corresponding rod connected to the piston.

Metering check valve

A relief valve includes a valve body having an inlet and an outlet; a passageway formed between the inlet and the outlet in the valve body; a valve tube positioned in the passageway having a generally cylindrical portion including a first outside diameter and a second generally cylindrical portion including a first inside diameter that is larger than the first outside diameter; a valve seat; and a spring positioned about at least a portion of the valve tube and biasing the valve tube away from the valve inlet to seal against the valve seat. The valve tube and valve seat prevent flow through the passageway when pressure at the inlet is below a predetermined pressure and wherein the valve tube moves axially away from the valve seat at the predetermined pressure allowing flow through the passageway from the inlet to the outlet.

Low noise relief valve

A manual release valve is provided for a electro-hydraulic actuator of the type including a piston movable in a cylinder and defining a piston side chamber and a rod side chamber, the valve threadedly attached to the housing of the actuator and extending at least partially within the fluid housing conduits, the valve moveable from a closed position fully seated in the housing to an open position for fluidly connecting both the piston side chamber and the rod side chamber to the reservoir, the valve further including a pressure relief portion that is operable when the valve is in the closed position for relieving pressure from at least one of the piston side chamber or the rod side chamber.

Electro-hydraulic actuator including a release valve assembly

An electro-hydraulic actuator includes a hydraulic pump, an electric motor operatively connected to the hydraulic pump and operable for driving the pump, an actuator moveable in response to fluid flow from the pump, and a housing for the pump, electric motor and actuator. The housing has a base member that is adapted to be modified into various configurations for forming an attachment interface for mounting of the electro-hydraulic actuator.

Electro-hydraulic actuator mounting

A hydraulic pump unit that includes a pump and an internal reservoir that is mountable as a unit to a towed vehicle. The hydraulic pump unit can be assembled in a plurality of configurations such that an inlet to the pump is located at a relatively low point within the internal reservoir depending on the orientation in which the unit is mounted to the towed vehicle. Thus, the power unit can be adapted for use in a plurality of applications thereby making the unit versatile.

Hydraulic braking power unit

A hydraulic system for an actuator provides staged operation during extend and retract. A pair of reversible pumps are conjointly driven by a reversible motor. A relief valve in the retract circuit directs fluid to tank when fluid pressure increases above a predetermined value. An unloader valve in the extend circuit is responsive to pressure at a first stage pump to direct flow to tank when the pressure increases above a second predetermined value. A non-return check valve connected between the pumps in the extend circuit closes the flow circuit to the second stage pump during high loads, so that the flow from the second stage pump goes to tank, and the return flow from the actuator goes only to the first stage pump. The non-return check valve is responsive (via a signal line to the retract circuit portion) to the pressure in the extend and retract circuit portions.

Bi-rotational, two-stage hydraulic system

A power-assist hydraulic system for use in connection with a linkage extending through a housing and mechanically coupled to an actuated member. The power-assisted hydraulic system includes a double-acting hydraulic cylinder having a rod configured for interconnection to the actuated member, an accumulator for storing pressurized hydraulic fluid and a rotary valve. The rotary valve has a valve interface for selectively connecting the hydraulic cylinder to the accumulator. The rotary valve has at least one valve piston for receiving pressurized hydraulic fluid to maintain a hydraulic balance at the valve interface. A sleeve having a bore through which the linkage can extend is mechanically coupled and movably mounted with respect to the rotary valve for moving the rotary valve between a neutral position and first and second rotated positions in response to forces between the linkage and housing. The sleeve and rotary valve cooperate to drive the hydraulic cylinder in a first or a second direction in response to the rotary valve being in the first or the second rotated position, respectively.

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Plymouth, MN, United States of America

David John Anderson