Abstract: A seal means 66 for a blade attachment slot of a rotor assembly 12 is disclosed. Various construction details which adapt the rotor assembly to block the leakage of cooling air from the blade attachment slot 40 as the cooling air is flowed to a rotor blade 22 are developed. In one embodiment, the seal means has a seal plate 68 and baffles 70,72 integral with the seal plate which define a cooling air chamber for receiving cooling air from a passage way 38 in a rotor disk 20. The seal plate extends axially and laterally to block the leakage of cooling air in the radial direction. Baffles extend radially from the plate for blocking the leakage of cooling air in the axial direction.

Abstract: A pneumatic positioner with a casing composed of a shell-like bottom part and a shell-like cover part. A membrane plate, is connected through a gas-tight membrane with the side walls of the casing so as to be movable back and forth in the casing in the direction of a drive spindle which is disposed in sealing relationship through the bottom part of the casing. In the bottom part and/or in the cover part, there are arranged one or more gas-conducting connecting pieces. In the casing there are arranged coil springs for producing biasing or restoring forces. These springs abut, on the one hand, the membrane plate and, on the other hand, the bottom part or cover part. On the membrane plate of one embodiment there is provided for each coil spring at least two supporting surfaces which present different spacings from a plane perpendicular to the direction of motion of the drive spindle and upon which the coil springs are replaceably disposed.

Abstract: A rotary to linear control for actuating an axially movable spool of a digital rotary input servovalve has a threaded drive between a rotating nut and a threaded shank directly connected to the spool. The threads are hydrostatically preloaded to eliminate thread backlash and provide improved valve-actuator stability. The rotary drive is a digital stepper motor capable of moving at incremental movements about its rotational axis which rotates the nut. The threads provide a preload and a cushioning effect which essentially provides an accurate reference position for the axially movable spool each time the threads are actuated.

Abstract: The piston comprises, fixed on a rod (9), a central element constituted by a thin perforated disc (8), and two lateral elements (6, 7) in which are provided valve members (21, 22) which cooperate with seats defined by the disc (8). The piston (1) is guided in a cylinder (2) by a ring (16) carried by the lateral elements (6, 7).

Abstract: A rotary and linear actuating device is disclosed for imparting precision rotary and linear movement to an external member or assembly. In a preferred form of the invention a rotatable assembly is rotated about an axis within a housing by selectively varying the relative pressures of an actuating fluid in at least a pair of fluid pressure chambers defined by the housing, the rotatable assembly and at least a pair of vane members extending therebetween. An elongated shaft member is rotationally fixed relative to the rotatable assembly and is supported by at least a pair of linear bearing assemblies to allow linear movement of the elongated shaft member along said axis. The linear bearing assemblies remain a fixed axial distance from one another in order to adequately support heavy loads on the elongated shaft member and the external member or assembly attached thereto.

Abstract: A cooling fan assembly made of plastic material is composed of a plurality of fan blades and a boss and connected to a viscous fluid coupling device rotatably mounted through a bearing assembly on a driving shaft of an automotive vehicle. An axially resilient connecting member in the form of a plate spring is fixed to the boss of the fan assembly at one end thereof and to the coupling device at the other end thereof, whereby the inertia moment of the fan rotation causes the appropriate rotation of the fan assembly in spite of possible misalignment of the coupling device with respect to the driving shaft to thereby protect the bearing assembly from being damaged. Helical or waved springs may be interposed between the fan boss and the coupling device in place of the plate spring.

Abstract: A reciprocating engine comprising a cylinder, a piston performing reciprocating movement within the cylinder, a crank shaft performing rotational movement, a connecting rod connected rotatably at its one end to the crank shaft and at its the other end to the piston, and rollers each mounted on the side portion of the piston, in which the piston is in rolling contact with the cylinder through the rollers.

Abstract: A fluid control system (10) for controlling the torque of a fluid motor (22) and varying the flow to the fluid motor (22) has a mechanism (56) to control the torque and flow in proportion to the operator's input to a pilot operated control valve (16) that controls the fluid motor (22). The mechanism (56) controls the torque and flow of the fluid motor (22) during both acceleration and deceleration of the fluid motor (22). The fluid control system eliminates the need for special, complicated control valves.

Abstract: The present invention comprises an apparatus for producing high pressure fluid by means of a cylinder having a reciprocatingly sliding ram inside, suction and pressurization of the fluid being performed by the reciprocation of said ram. In the apparatus, an oil chamber is positioned on the intensifying side within said cylinder, and lubricating oil in said oil chamber is caused to have a pressure equivalent to that of the high pressure fluid produced. This oil pressure is transmitted to the slidable contact portions of the ram. The apparatus is capable of detecting the lack of lubricating oil, when such lack of lubricating oil occurs.

Abstract: An open center, load sensing hydraulic system is disclosed which contains a primary work circuit and a secondary work circuit. A fixed displacement pump is fluidly connected between a reservoir and both the primary and secondary work circuits for supplying pressurized fluid thereto. The primary work circuit includes a control valve which regulates fluid flow from the pump to a primary hydraulic function and which includes a feedback mechanism connected thereto. The secondary work circuit includes a manually operable control valve for regulating fluid flow from the pump to a secondary hydraulic function. A priority valve is connected between the pump and both the primary and secondary work circuits and is movable to regulate the pressure to the primary work circuit.

Abstract: A closed center, load sensing hydraulic system is disclosed which contains a primary work circuit which has priority in flow demand over a secondary work circuit. The system includes a variable displacement pump fluidly connected between a reservoir and a control valve with the primary work circuit. The primary work circuit includes a control valve which regulates fluid flow from the pump to a primary hydraulic function and which includes a feedback mechanism connected thereto. The secondary work circuit also includes a manually operable control valve for regulating fluid flow from the pump to a secondary hydraulic function. A priority valve is connected between the pump and the secondary work circuit and movable between an open and a closed position to regulate the pressure of fluid discharged by the pump.

Abstract: The control valve comprises a member defining an orifice for fluid and a resilient plate arranged to control flow of fluid through the orifice by flexing movement relative to the orifice. The plate may comprise a disc which is freely movable between first and second stops. The plate is arranged to engage the first stop to control fluid flow in one direction through the orifice by said flexing movement and is arranged to engage the second stop to permit relatively greater flow when fluid flows in the opposite direction through the orifice.

Abstract: An open center hydraulic system is disclosed which contains a primary work circuit and a secondary work circuit. A fixed displacement pump is fluidly connected between a reservoir and the primary and secondary work circuits for supplying pressurized fluid thereto. The primary work circuit includes a control valve which regulates fluid flow from the pump to a primary hydraulic function and which includes a feedback mechanism connected thereto. The secondary work circuit also includes a manually operable control valve for regulating fluid flow from the pump to a secondary hydraulic function. A priority valve is connected between the pump and the secondary work circuit and is movable between an open and a closed position to regulate the pressure of fluid discharged by the pump.

Abstract: A method of controlling a pneumatically operated servo-motor (1) having a linearly movable operating rod (6) is described in which the actual position of the operating rod is monitored continuously during each stroke, and when the rod reaches a position which lies a predetermined amount in front of a limit position reached during the preceding stroke the speed at which the operating rod travels towards the corresponding limit position of the current stroke is modified. In particular the method is used in a clutch actuating servo-motor to brake the speed of the operating rod at a position which corresponds to the initial contact between the clutch friction surfaces when the rod is moving to engage the clutch, so that the free travel of the clutch is taken up as quickly as possible, but the actual engagement is slowed in order to avoid undesirable jerkiness and wear.