Abstract: A test system and method for in line testing of shock suppressor shut-off valves is provided. Vacuum and fluid canisters are mounted to a backpack that can be carried by maintenance personnel to the operating locations of shock suppressors. The fluid canister contains a fluid for being driven through the shut-off valves of the shock suppressor during testing. Fluid lines interconnect the canisters and the shock suppressor. A valve assembly is disposed within the fluid lines for regulating the rate of flow of the fluid from the fluid canister to the shock suppressor. The system further includes structure disposed within the fluid lines for evacuating the fluid lines and the valve assembly prior to testing of the shut-off valves.

Abstract: A servo valve controls the rate and direction of flow of a hydraulic fluid from a fluid power system to impart reciprocating motion to the piston of a hydraulically driven motor. An outer sleeve member of the servo valve has entry and exit ports connected to the source of fluid power and motor control ports connected to the hydraulically driven motor. A slider member is positioned within a cylindrical opening through the sleeve member and includes fluid chambers within the slider for alternating the direction of fluid flowing to the hydraulically driven motor by rotating the slider member. The rate of fluid flow is controlled by the lateral movement of the slider within the sleeve member.

Abstract: A data collection and reduction system for a shock suppressor valve test system is provided. The test system includes a flow meter for generating a DC voltage signal corresponding to the velocity of fluid flowing through the flow meter and a recorder for recording and outputting an AC voltage signal corresponding to the velocity of fluid flowing through the flow meter. The data collection and reduction system includes circuitry interconnected to the flow meter for amplifying the DC voltage signal generated by the flow meter to produce an amplified DC voltage signal. Circuitry converts the amplified DC voltage signal to an AC voltage signal for application to the recorder for recordation of the velocity of the fluid flowing through the flow meter. Circuitry is further provided and interconnected to the recorder for amplifying the AC voltage signal output by the recorder.

Abstract: A bleed and fill system apparatus and method for in line servicing of shock suppressor reservoirs is provided. Vacuum and fluid canisters are mounted to a backpack that can be carried by maintenance personnel to the locations of shock suppressors. The apparatus includes a valve for attachment to the reservoir of the shock suppressor. Fluid lines interconnect the valve to the canisters. The valve is operable to independently connect either the vacuum canister or the fluid canister to the reservoir of the shock suppressor, such that when the vacuum canister is connected to the reservoir, air is bled from the fluid lines and connections to the shock suppressor and when the fluid canister is connected to the reservoir, fluid enters the reservoir to replace lost fluid. The system thereby permits in line servicing of shock suppressors without removal of the shock suppressor from its housing and mountings.

Abstract: A valve device includes primary and secondary fluid systems. The secondary fluid system includes source pressure and controlled pressure channels containing secondary fluid at source and controlled pressures, respectively. A master cylinder primary fluid source is connected through first and second parallel paths to a primary fluid portion of a changeover cavity which is also connected to the brake cylinders of a vehicle. The changeover cavity includes primary and secondary movable piston member therein, separating primary and secondary fluid portions thereof. Each parallel primary path includes a valve member for controlling the flow of primary fluid to the primary portion of the changeover cavity.