Abstract: A linear actuator for pumping comprising a stator having an inner opening, a shaft having a plurality of permanent magnets spaced linearly in the axial direction, the shaft disposed in the stator opening and configured to reciprocate linearly in the axial direction relative to the stator, the stator comprising a first stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a second stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a bearing assembly positioned axially between the first stator assembly and the second stator assembly, and the bearing assembly having a width that is a function of the spacing of the plurality of pole sections of the first stator assembly and the second assembly and the spacing of the plurality of permanent magnets of the shaft.

Abstract: A linear actuator for pumping comprising a stator having an inner opening, a shaft having a plurality of permanent magnets spaced linearly in the axial direction, the shaft disposed in the stator opening and configured to reciprocate linearly in the axial direction relative to the stator, the stator comprising a first stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a second stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a bearing assembly positioned axially between the first stator assembly and the second stator assembly, and the bearing assembly having a width that is a function of the spacing of the plurality of pole sections of the first stator assembly and the second assembly and the spacing of the plurality of permanent magnets of the shaft.

Abstract: An overspeed protection system for an aircraft fan engine wherein blades are rotatable from a coarse pitch to a fine pitch to a thrust-reverse condition. A wobbler-type hydraulic motor is provided for rotating the blade. An overspeed governor is operatively associated with the motor for effecting rotation of the blades in a direction toward the coarse pitch condition. A control, including a solenoid valve actuatable in thrust-reverse mode, changes the sense of the hydraulic motor to drive the motor further into thrust-reverse on actuation of the overspeed governor means.

Abstract: An overspeed governor for adjusting the blade pitch of a propulsor in an unducted fan aircraft engine to prevent propulsor overspeed comprises a flyweight governor which is rotated in response to rotation of the propulsor, a governor pilot valve with a valve spool which is axially moved in response to actuation of the flyweight governor for adjusting the blade pitch of the propulsor, and a governor checkout apparatus which sensitizes the flyweight governor so that it is actuated to maintain a substantially lower propulsor rotative speed during a start-up operation of the engine as compared with during normal operation, whereby the operation of the governor can be checked out during start-up operation of the aircraft engine.

Abstract: An overtravel stop for a rotary shaft (12) is disclosed having first and second embodiments. In the first embodiment, braking torque for the shaft is supplied by the restriction by valve (14) of at least hydraulic fluid flowing in low pressure hydraulic fluid return line (18) from a hydraulic motor (22) which is connected to the shaft by a drive unit (24) in response to movement of a movable stop (34, 36) to a travel limit along an axial travel path to stop the hydraulic motor. In the second embodiment, braking torque for the shaft is supplied by a combination of a mechanical stop produced by the interaction of stop jaws (82, 84) which are respectively carried by an axially movable annular member (32) and a fixed stop (86) and the restriction of at least the low pressure hydraulic return fluid line (18) by a valve (14).

Abstract: An overtravel stop for a rotary shaft, including a fixed stop having at least a pair of stop jaws disposed at different radii from the axis of the rotary shaft. A follower member is provided about the rotary shaft and is adapted to rotate with the shaft within a selected travel limit. The follower member is associated with a stop member having at least a pair of stop jaws disposed at the same different radii as the stop jaws of the fixed stop. The follower member is rotationally shiftable with respect to the shaft when the shaft reaches its travel limit. The stop member is axially movable into engagement with the fixed stop when the follower member rotationally shifts relative to the shaft. At least some of the stop jaws have negative rake angles, and a shock absorber is provided behind the fixed stop.

Abstract: Thrust bearing failure in clutches is avoided in a clutch construction including a housing 10 with first and second coaxial shafts 24, 32 and a clutch pack 34 interconnecting the shafts 24 and 32 for coupling and decoupling the same. A spring 50 is utilized to engage the clutch pack 34 to couple the shafts 24 and 32 while a motor 82, 96 is utilized to decouple the shafts by releasing compression on the clutch pack 34. This is accomplished by moving a thrust bearing 76 to engage a reaction plate 48 forming part of the clutch pack 34 to move the same away from the other reaction plate 34 of the clutch pack to disengage the clutch. The thrust bearing 76 is wholly out of the load path of the clutch when the clutch is engaged.