A knockdown, portable lift is relatively compact and lightweight for transport and use where there is no existing means for lifting a load between a lower surface and an upper surface or where the existing means cannot be used. Components of the lift are stored in a base portion of the lift and are assembled on site for forming a lift frame extending between the upper and lower surfaces. A platform and drive assembly are supported on the lift frame and are driven together up and down tracks on each side of the lift frame using a rotary drive, such as a hand crank or electric motor, to power the drive assembly. The drive assembly is operable by a person on or off the platform from either the upper or lower surface or traversing stairs over which the platform is moving. The drive assembly incorporates a unique overspeed braking system and a unique clutch arrangement.

A rotary actuator has a stop module configured to mechanically link two gear stages travelling at different rotational speeds when an end-of-stroke travel limit is reached, thereby causing the rotary actuator to bind because relative motion between the gear stages is impeded.

A rotary actuator has a stop module configured to mechanically link two gear stages travelling at different rotational speeds when an end-of-stroke travel limit is reached, thereby causing the rotary actuator to bind because relative motion between the gear stages is impeded.

A braking system for slideway guided amusement vehicles providing both manual and automatic braking for the slideway guided amusement vehicles is provided. The braking system includes at least one brake handle, a first shaft fixed to the at least one brake handle, a first gear concentrically positioned on and free to spin independently of the first shaft, an actuator fixed to the first shaft for providing a linear motion to a stop pin, an inlet opening on the first gear for receiving the stop pin, a second gear coupled to the first gear, concentrically fixed on a second shaft for mounting spinnably and extending horizontally to a chassis of a vehicle, at least one friction member attached to the second shaft, a tensioning means, and a control unit adapted to remove the stop pin from the inlet opening via the actuator.

A braking system for slideway guided amusement vehicles providing both manual and automatic braking for the slideway guided amusement vehicles is provided. The braking system includes at least one brake handle, a first shaft fixed to the at least one brake handle, a first gear concentrically positioned on and free to spin independently of the first shaft, an actuator fixed to the first shaft for providing a linear motion to a stop pin, an inlet opening on the first gear for receiving the stop pin, a second gear coupled to the first gear, concentrically fixed on a second shaft for mounting spinnably and extending horizontally to a chassis of a vehicle, at least one friction member attached to the second shaft, a tensioning means, and a control unit adapted to remove the stop pin from the inlet opening via the actuator.

A fall-protection apparatus with a drum and a rotationally-activated braking device including at least one velocity-actuated pawl that is mounted on a pawl-support plate that is rotatable relative to the drum through a predetermined range between a first position and a second position. The pawl-support plate is rotatable relative to the drum from the first position to the second position upon the pawl-support plate experiencing a rotational acceleration that is above a predetermined threshold value of rotational acceleration. When the pawl-support plate is in the second position, the velocity-actuated pawl can be actuated by a rotational velocity that is lower than a rotational velocity required to actuate the pawl when the pawl-support plate is in the first position.

A fall-protection apparatus comprising a rotationally-activated braking device that comprises at least one flexure-borne pawl and at least one buttress that is on a sidewall of a rotatable drum of the braking device.

A fall-protection apparatus comprising a rotationally-activated braking device that comprises at least one flexure-borne pawl and at least one buttress that is on a sidewall of a rotatable drum of the braking device.

A no-back brake includes a torque tube and a brake. The brake is configured to be axially displaced in response to a force to prevent the torque tube from rotating. The brake includes a rotor that is concentric with the torque tube and that is fixed to the torque tube so that the rotor rotates with the torque tube. The brake includes a stator that is concentrically mounted on the torque tube so that the torque tube is rotatable relative to the stator. The brake includes a friction device located between the rotor and the stator. The friction device is configured to form a frictional coupling between the rotor and the stator that opposes relative rotational motion between the rotor and the stator when the brake is axially displaced. The frictional device includes a composite material.

Methods and systems are provided for a device. In one example, the device is configured to automatically grab and slip a line. The device is further configured to decrease degradation to the line by limiting a rotation of the device via contact with the line.