Abstract:
In an actuator (102), a piston head portion (108) reciprocates in a large diameter section of a cylinder casing (102), dividing such section into first and second variable volume chambers (112, 116). An end portion (104) projects outwardly of the cylinder casing (102) and includes a mounting (162) at its end. The opposite end portion (106) extends into a third variable volume chamber (120). A piston head portion (82) reciprocates in a piston section (72) of a volumetric compensator (14). One end portion of piston (80) is slidably received within first variable volume chamber (90). The opposite end portion (86) of the piston (80) extends through a central opening in a diverter wall (88) between the piston section (72) and a gas charge section (78). Pressurized gas within the gas charge section (78) acts on the second end (86) of the piston (80), forcing hydraulic fluid in chamber (90) to chamber (120 ) of actuator (102). The gas pressure in chamber (116) and the hydraulic fluid pressure in chamber (120) both exert a force between the actuator piston and cylinder casing tending to extend or elongate the actuator (102). Variable volume chamber (100) of the compensator (14) and variable volume chamber (112) of the actuator are interconnected and fluid is transferred back and forth between them during movements of the compensator and actuator pistons.
Abstract:
The actuator (12) comprises three main parts, an outer casing (20), a movable piston (28) and a fixed piston (36). A stepped outer portion (50, 52, 54) of the movable piston (28) cooperates with a stepped cavity (40, 42, 44) in the casing (20) to define a plurality of concentric, variable diameter fluid chambers (1, 2, 3) bounded at their ends by radial surfaces on the movable piston (20) and within the casing cavity. The movable piston (20) and the fixed piston (36) define a plurality of axially spaced apart variable diameter fluid chambers (1', 2', 3') which are bound on their ends by radial surfaces on the fixed piston (36) and radial surfaces within the cavity formed in the movable piston (20). One set of the chambers (1, 2, 3) is connected to supply pressure (P.sub.S) and the second set of chambers (1', 2', 3') is connected to return pressure (P.sub.R). Seal receiving grooves are formed in outer surface portions of the fixed and movable pistons (28, 36). Seal rings (S.sub.R) within these grooves seal against mating internal surfaces of the stepped cavities.
Abstract:
A flight control surface (1) is supported from an aircraft frame structure (12), for pivotal movement about a hinge axis. The surface (10) is deployed against an aerodynamic load which is a function of surface deflection and imposes a torque on the flight control surface (10) wanting to rotate it back to a neutral trim position. A counterbalancing hydraulic actuator (16, 16', 226, 334, 372, 402) is connected between the frame structure (12) and the flight control surface (10). This actuator (16, 16', 226, 334, 372, 402) is oriented to oppose a counterbalancing torque on the flight control surface (10) acting in opposition to the torque imposed by the aerodynamic load. A controllable, separate actuator (34, 312, 422) is interconnected between the frame structure (12) and the flight control surface (10) and is operated for positioning the flight control surface (10).
Abstract:
An electric stepping motor, operated by command pulses from a computer or microprocessor, rotates a rotary control member of a distributor valve, for sequencing hydraulic pressure and flow to the cylinders of one or more axial piston hydraulic motors. A group of the cylinders are subjected to pressure and flow and the remaining cylinders are vented to a return line. Rotation of the rotary control member sequences pressurization by progressively adding a cylinder to the forward edge to the pressurized group and removing a cylinder from the trailing edge of the pressurized group. The pistons of each new pressurized group function to rotate a wobble plate into a new position of equilibrium and the hold it in such position until another change in the makeup of the pressurized group. An increment of displacement of the rotary pressurized group. An increment of displacement of the rotary hydraulic motor occurs in direct response to each command pulse that is received by the stepping motor. In an installation which includes two hydraulic motors connected to a common output, the rotary distributor valve functions to alternate driving pulses of hydraulic pressure and flow between the two motors.
Abstract:
An electric stepping motor, operated by command signals from a computer or a microprocessor, rotates a rotary control member of a distributor valve, for sequencing hydraulic pressure and hence flow to the cylinders of an axial piston hydraulic machine. A group of the cylinders are subjected to pressure and flow and the remaining cylinders are vented to a return line. Rotation of the rotary control valve member sequences pressurization by progressively adding a cylinder to the forward edge to the pressurized group and removing a cylinder from the trailing edge of the pressurized group. The double ended pistons of each new pressurized group function to drive a wobble plate into a new position of equilibrium and then hold it in such position until another change in the makeup of the pressurized group. These pistons also displace hydraulic fluid from the opposite cylinder head which serves as the output of a pumping element. An increment of displacement of the wobble plate occurs in direct response to each command pulse that is received by the stepping motor. Wobble plate displacement drives the rotary valve of the hydraulic power transfer unit, causing it to transfer hydraulic fluid from a first expansible chamber on one side of a piston in a hydraulic ram to a second expansible chamber on the opposite side of the piston. Reverse drive of the hydraulic power transfer unit reverses the direction of transfer of hydraulic fluid between the two expansible chambers.
Abstract:
The system includes an inertial body on which is mounted a mirror, which together are mounted for rotation by a gimbal bearing element. The gimbal bearing element is part of a base system which further includes a light beam source, such as a laser. The mirror is positioned on the inertial body so that it is at an angle of 45.degree. relative to the axis of the gimbal bearing element. The inertial body, which can be represented by a dumbbell-shaped equivalent mass, is oriented so that the path of the light beam from the light source is coincident with the gimbal axis, i.e. such that the light beam strikes the mirror. A yaw-like disturbance, i.e. a rotational vibration about the Z coordinate axis, affecting the base system, and hence the light beam source and gimbal bearing element as well, is converted into a rotational movement of the inertial body and the mirror about the axis of percussion, which, in the embodiment shown, causes a rotation of the reflected beam about the Y coordinate axis. The reflected beam impinges on a second mirror, which is positioned at a 90.degree. angle relative to the mirror on the inertial body. The rotation of the reflected beam compensates for the effect of the disturbance about the Z axis on the beam, so that the beam reflected from the second mirror remains steady in the far field.
Abstract:
A flap (22) carries a guide roller (24) at each of its ends. Each guide roller (24) travels within a fore and aft track (28) positioned immediately endwise outwardly of its end of the flap (22). The flap (22) is extended and retracted by means including a reaction link (36) and a two-way linear actuator (38). The actuator (38) and the reaction link (36) are pivotally connected at their forward ends to the outer end of a bell crank arm (34), for pivotal movement about a common axis (40). At its rearward end the actuator (38) is pivotally attached to the flap at a location (44) offset above the roller (24). The reaction link (36) is pivotally attached at its rearward end to the flap (22) at a location (42) offset below the roller (24). Rotation of the bell crank arm (34) alone will result in the flap (22) being translated rearwardly and rotated downwardly, i.e. Fowler flap movement. Extension or retraction of the actuator (38) will cause a rotation of the flap (22) about the axes (26) of the rollers (24).
Abstract:
Lubrication gas for a steel ball is delivered to the ball by a gas distribution manifold ring that surrounds an upper portion of the ball. Such ring presents an annular seat directed towards the ball and includes gas delivery orifices directed to discharge against the ball. Gas under pressure is delivered through the orifices, to provide a lubricating gas film between the seat and the ball, attended by downwardly directed fluid forces acting on the ball. A pressure chamber is provided below the ball. A regulated gas pressure is maintained within such chamber during pressurization of the bearing, for pressure loading the ball upwardly towards the bearing seat. A support pad ring is provided below the ball to support the ball during those times that the bearing is not pressurized and to preposition the ball to allow pressurization of the chamber below the ball by restricting the gap between the ball and the seat elements.
Abstract:
This invention relates to integrated electro-hydraulic actuators for use aboard aircraft or elsewhere. A balanced, double-acting hydraulic ram or motor (12) is connected between a support (16) and a member to be moved relative to the support. The ram includes first and second changeable volume hydraulic chambers (30, 32). A reversible hydraulic pump (38) is connected by a pair of conduits (44, 46) to the ram chambers (30, 32). The pump (38) displaces hydraulic fluid from one chamber to another for the purpose of causing a pressure differential between them. A hydraulic accumulator (60) provides leakage makeup fluid to the actuator, and further provides a quiescent pressure to the actuator when it is in a substantially nonoperative condition. A conduit (62) may connect the accumulator (60) to the ram (12). A laminar leakage flow path within the actuator permits hydraulic connection of the accumulator (60) to the ram (12) without use of valves.