Abstract: An electromechanical actuator is disclosed having either a rotary output or a linear output for moving an external load, the actuator having at least two drive motors, a synchronizer connected to the outputs of the drive motors, a differential mechanism combining the outputs of the drive motors, and a quick release mechanism connected to the differential mechanism and the actuator output, the quick release mechanism releasing support of the external actuator load in response to an internal actuator jam and maintaining support or the external actuator load in response to an external actuator overload.

Abstract: A transmission with a load brake has a ball spline and a stabilizer ring for reducing chatter, a seal for preventing leakage, and an adjustment mechanism for extending the effective life of the brake disk stack. In the past, transmissions equipped with Weston brakes have experienced significant problems with instability and chatter. The present invention overcomes the problems of instability and chatter by introducing a ball spline at the junction between the output shaft and the loading assembly. The ball spline reduces friction caused by the axial movement of the output cam of the loading assembly. Also, the invention introduces a stabilizer ring around the loading assembly to reduce instability and chatter caused by the angular and transverse movement of the loading assembly. The invention also may also utilize a fluid damper in place of the stabilizer ring to reduce instability and chatter caused by the angular and transverse movement of the loading assembly.

Abstract: A positive locking device is provided in order to prevent a motor from rotating after power has been removed. The positive locking device has a plate mounted on the motor which engages a disk or hub on the shaft of the motor. In another aspect of the invention, solid state circuitry for switching a permanent magnet motor and providing dynamic braking thereto is provided. The circuitry allows the back EMF generated by the armature coils of a permanent magnet motor to cause a current to flow through the motor when power is removed. This back EMF may be used to help produce smooth engagement of the locking device. In another aspect of the invention, a dynamic braking circuit for a dual armature permanent magnet motor is provided. By applying current to one or the other of two oppositely wound armature coils the motor is made to rotate in either direction. When power is removed from the active armature, this armature is short-circuited through a diode.

Abstract: A positive locking device is provided in order to prevent a motor from rotating after power has been removed. The positive locking device has a plate mounted on the motor which engages a disk or hub on the shaft of the motor. In another aspect of the invention, solid state circuitry for switching a permanent magnet motor and providing dynamic braking thereto is provided. The circuitry allows the back EMF generated by the armature coils of a permanent magnet motor to cause a current to flow through the motor when power is removed. This back EMF may be used to help produce smooth engagement of the locking device. In another aspect of the invention, a dynamic braking circuit for a dual armature permanent magnet motor is provided. By applying current to one or the other of two oppositely wound armature coils the motor is made to rotate in either direction. When power is removed from the active armature, this armature is short-circuited through a diode.

Abstract: Methods and apparatus for generating a linear vibratory output force having a variable amplitude. The force is generated by the cooperation of four rotating eccentric masses that are grouped in two pairs of two masses. The masses in each pair are counter-rotating (i.e., they rotate at the same speed but in opposite directions). The phase relationship between the two pairs is adjustable. For example, the phase of one pair can be advanced while the phase of the other pair is retarded by an equal amount, thereby changing the amplitude of the output force without changing the direction along which the force acts, and also without changing its frequency if desired.

Abstract: An electro-mechanical actuator has two motors which normally operate at the same speed and combine (sum) to move a load via a rotary actuator output member. If the motors begin to operate at different speeds, this indicates that the system has failed, and the output member is automatically decoupled from the remainder of the actuator. This leaves the output member free to rotate relative to the remainder of the actuator. The speeds of the motors are monitored by a differential mechanism which produces a rotary output proportional to the average of the two motor speeds. This average is normally the same as the speed of the output member. Decoupling of the output member occurs when this average deviates from the output member speed.