A system and method for preventing back-drive in a braking system for a rotary actuator. The braking system comprises a housing and split cam design. A driving cam located within the housing is associated with an upstream side of the braking system. The driving cam is configured to rotate when a torque is applied to the upstream side. The braking system has a wedging cam and a plurality of cylindrical rollers. The wedging cam located within the housing and is associated with a downstream side of the braking system. The wedging cam is configured to react and prevent back-drive motion when torque is applied to the downstream side. The plurality of cylindrical rollers is positioned between the wedging cam and the housing. The plurality of cylindrical rollers is configured to wedge between a surface of the wedging cam and the housing when the torque is applied to the downstream side.

Methods and systems are provided for an actuation system for a parking mechanism in a transmission system of a vehicle. In one example, a system may include an actuator coupled to a lever arm via one or more parallel axis gears, and a shaft connecting the lever arm to a pawl of the parking mechanism, the lever arm non-back drivable at each of a first state and a second state of the actuation system.

A self-locking mechanism includes: a housing having a through hole and a dodge hole; an elastic member in the dodge hole, the elastic member being connected to a wall of the dodge hole and having a free end capable of swinging in a thickness direction of the housing; a first engaging member on the elastic member; a knob on an outer side of the housing and having one end passing through the through hole; a plurality of second engaging members on a side of the knob adjacent to the housing; wherein the first engaging member may be engaged with or disengaged from one of the second engaging members under an action of an elastic deformation of the elastic member as the knob rotates; and a driven member on an inner side of the housing and fixedly connected with the knob so as to be rotated under driving of the knob.

A self-locking apparatus for a gear set permits forward-driving an input in clockwise or counterclockwise directions and substantially prevents an output from being driven in either or both of those directions. The device includes a gear set with planet gears arranged within a planet carrier within a fixed ring gear. Each of the planet gears is engaged with the planet carrier via a differentiating connector retained in an elongated slot in the planet carrier where it moves to the clockwise position when being forward driven in the clockwise direction and, when the planet carrier is back driven in the clockwise direction, the connector moves to the counter-clockwise position in the slot. This arrangement allows the gear set to be forward driven but not back driven. This differentiated action can engage/disengage with any form of unidirectional engage/disengage mechanism. The apparatus is useful in industrial applications requiring self-locking gear sets.

A locking mechanism to prevent back-drive includes a locking shaft with guide grooves. Locking shaft guides engage the guide grooves to constrain lateral motion of the locking shaft. A nut includes corresponding grooves to the locking shaft, and engages the locking shaft to prevent linear translation. The locking mechanism may be incorporated into a aircraft seat armrest to create a positive lock in the armrest position.

A drive arrangement for adjusting an aerodynamic flap on a vehicle. The drive arrangement includes an electric motor, a spur gear mechanism having gear stages, an output shaft, and at least two housing halves. The spur gear mechanism includes at least one self-locking gear stage that does not form the first gear stage nor the last gear stage of the spur gear mechanism. A safety coupling is arranged between the self-locking gear stage and the output shaft to disengage the output drive on overload in order to protect the flap attached thereto from damage.

A gearing arrangement for an actuator device for height adjustment of a vehicle body is provided, having a drive wheel and an output wheel, which are rotatably connected to each other by a tooth system formed on each. A blocking element is arranged on the output wheel to block a rotational movement, and a guide track having a blocking stop integrated therein and at least one deflection position; the guide track is connected to a pin section, which is movable to a limited degree and which is provided in order to be guided along the guide track upon rotation of the output wheel and to block a rotational movement of the output wheel upon penetrating into the blocking stop. By using the at least one deflection position, the rotative position of the blocking element can be detected during guiding of the pin section by the at least one deflection position.

A rotary drive member drives a driven member. A ring surrounding the driven member has two cam recesses containing lock members between cam surfaces of cam recesses and the ring. Each recess accommodates an associated lock member at different locations where the recess is shallower. Driving the driven member is permitted in a given rotation relative to the ring, but each lock member inhibits rotation of the driven member in the opposite sense. The recesses extend in opposite directions. Coupling between the driven members is free-play whereby reversal in the rotation disengages members and reengages. Protuberances extending into cam recesses retain a lock member associated with one recess at the deeper location permitting movement of the other lock member towards the shallower location. Upon reversal of the rotation, the protuberances retain another lock member at the deeper location permitting movement of one lock member.

An arrangement including a bushing having a bushing hub, a bushing flange, a housing containing a uni-directional bearing, an axle extending outward from the uni-directional bearing, and a stationary torque arm attached to the axle of the bushing. The bushing hub is inserted into a recessed hub section of a sprocket, and securely connected to the sprocket. The arrangement may also include a driven device attached to the bushing hub, and an endless drive belt and motor.

A gear apparatus for controlling movement of an output by an input coupled to a power source. The apparatus an input member coupled to the input, an output member coupled to the output and the input member so that movement of the input member causes movement of the output, a selectably releasable member coupled to the input member and the output member, wherein the selectably releasable member remains in a fixed position while the input member and the output member move, and a releasable member brake mechanism coupled to the selectably releasable member, wherein the releasable member brake mechanism is arranged to prevent movement of the selectably releasable member when the input member and the output member move and to allow back driving of the selectably releasable member.