A window covering includes a housing, a covering material, a spindle, and a driving device. The spindle and the driving device are provided at the housing. The driving device includes a motor having a shaft, and an epicyclic gearing decelerating device having an input end and an output end connected to the shaft and the spindle, respectively. Whereby, the spindle can drive the covering material to expand or to collapse. The epicyclic gearing decelerating device includes a ring portion and at least a planet gear assembly which is coupled between the input end and the output end. The planet gear assembly includes a plurality of planet gears having a Shore A durometer hardness of 45-90, which is rotatable along the fixedly provided ring portion. While being driven to move, a lower end of the covering material moves at a speed higher than 65 mm per second.

A self-activated no-back device includes a housing, an input shaft, an output shaft, a reactor hub, first grooves, a brake hub, second grooves, a plurality of balls, a reactor plate, a brake pack, a reactor spring, and a load spring. The first grooves are formed on an interior side of the reactor hub interior side, and the second grooves are formed in an interior side of the brake hub. Each second groove is aligned with a different first groove to define a plurality of groove pairs. Each ball is positioned in a different one of the groove pairs. One side of the reactor plate contacts the reactor hub. The brake pack is selectively contacted by the brake hub. The reactor spring supplies a spring force to the reactor plate, and the load spring supplies a spring force to the brake pack.

The present invention provides a safety training device capable of being attached to an existing front-wheeled walker. The safety training device a modified ski unit, a braking mechanism, a brake cable and hose. When improper transfer techniques are utilized by a patient, the modified ski unit engages the brake and cable hose to exert a force to the braking mechanism. The braking mechanism activates a braking member on the wheel of the walker, halting further movement of the patient and walker. Simultaneously, a striking member of the braking mechanism makes contact with the frame of the walker, producing an audible cue, alerting the patient and any healthcare professionals present that improper technique is being used in a transfer.

The present invention provides a safety training device capable of being attached to an existing front-wheeled walker. The safety training device a modified ski unit, a braking mechanism, a brake cable and hose. When improper transfer techniques are utilized by a patient, the modified ski unit engages the brake and cable hose to exert a force to the braking mechanism. The braking mechanism activates a braking member on the wheel of the walker, halting further movement of the patient and walker. Simultaneously, a striking member of the braking mechanism makes contact with the frame of the walker, producing an audible cue, alerting the patient and any healthcare professionals present that improper technique is being used in a transfer.

A compact, efficient, and reliable electromechanical actuator that is capable of driving heavy loads at a high rate of speed and also capable of resisting large back driving forces. The actuator resists tension and compression back driving forces in a static state as well as when the actuator extends and retracts. The back driving forces are resisted even if the electronics (e.g., motor) fail.

A compact, efficient, and reliable electromechanical actuator that is capable of driving heavy loads at a high rate of speed and also capable of resisting large back driving forces. The actuator resists tension and compression back driving forces in a static state as well as when the actuator extends and retracts. The back driving forces are resisted even if the electronics (e.g., motor) fail.

A linear actuator (1) and the centrifugal safety device (50) thereof is disclosed. The safety device (50) includes an outer socket (51) having a stop portion (512) and a first accommodation portion (513), an inner socket (53) having a raised portion (531) and a second accommodation portion (532) and a centrifugal assembly (55) having a centrifugal block (551) and an elastic element (555). The inner socket (53) drives the centrifugal assembly (55) to rotate. If the centrifugal force of the centrifugal block (551) is smaller than the elasticity of the elastic element (555), then the centrifugal block (551) is limited in the second accommodation portion (532) by the elastic element (555), or else the centrifugal block (551) moves into the first accommodation portion (513) and clamped by the raised portion (531) and the stop portion (512).

The centrifugal positive locking brake works inversely, that means, locking upon stopping and decoupling on start-up. When the drive motor is de-energized, the fixed ratchet(s) hit against at least one locking abutment on a locking disc positively fixed to the frame and lock the shutter. When voltage is applied, and with the associated quick start-up of the drive motor , the ratchet(s) disengage because of their inertia. This centrifugal positive locking brake for shutter drives is operated with a specially designed control method. After the power supply is interrupted, the ratchet(s) are drawn inward by the reloaded spring(s) so that they run against the locking abutment(s) and the shutter reliably locks in this position.

The centrifugal positive locking brake works inversely, that means, locking upon stopping and decoupling on start-up. When the drive motor is de-energized, the fixed ratchet(s) hit against at least one locking abutment on a locking disc positively fixed to the frame and lock the shutter. When voltage is applied, and with the associated quick start-up of the drive motor , the ratchet(s) disengage because of their inertia. This centrifugal positive locking brake for shutter drives is operated with a specially designed control method. After the power supply is interrupted, the ratchet(s) are drawn inward by the reloaded spring(s) so that they run against the locking abutment(s) and the shutter reliably locks in this position.

An elevator brake, having a rotatable component mounted to a shaft, is monitored for contamination by projecting electromagnetic radiation onto the rotatable component or onto the shaft, and receiving reflected electromagnetic radiation. If the monitored zone on the rotatable component or the shaft becomes contaminated, for example with oil or grease, the nature of the electromagnetic radiation reflected from the zone will change noticeably.