The present disclosure may be embodied as a rotary actuator for lifting a load against gravity. The actuator includes a housing and a drive motor attached to the housing. The drive motor has a drive shaft. The drive shaft may be configured to be manually operated. A rotatable output shaft is attached to the housing and in mechanical communication with drive shaft. The actuator includes at least one spring which is configured to act on the output shaft to at least partially offset a weight of the load. The at least one spring may be a torsion spring. The at least one spring may be configured to unwind when the motor is driven to lift the load, and may be configured to be wound when the motor is driven to lower the load. The at least one spring may comprise a plurality of springs, such as torsion springs.

A backdrive braking element is provided for preventing backdrive of a shaft. It includes a poly-lobed locking mechanism including an unlock shaft that has a polygon shaped inside profile and is coupled to a poly lock drive and brake assembly. The poly lock drive and brake assembly includes a plurality of poly lock drive and brake segments and is contained within the interior cavity of a housing.

Disclosed herein are winches comprising an overload protection mechanism. Certain aspects can comprise a drive gear frictionally coupled to a driven gear. Winch assemblies disclosed herein also can be configured to connect to common power tools such as may allow a user to operate the winch without specific training or knowledge of the application to which the winch is applied, without concern for damaging the tool within which the winch is applied. Material lifts, for instance, are contemplated herein as comprising the disclosed winches.

Disclosed herein are winches comprising an overload protection mechanism. Certain aspects can comprise a drive gear frictionally coupled to a driven gear. Winch assemblies disclosed herein also can be configured to connect to common power tools such as may allow a user to operate the winch without specific training or knowledge of the application to which the winch is applied, without concern for damaging the tool within which the winch is applied. Material lifts, for instance, are contemplated herein as comprising the disclosed winches.

A skip hoist of a blast furnace includes a winch system. In order to provide an improved drive system for a skip hoist of a blast furnace, the winch system includes a winch drum, rotatably mounted about a drum axis; at least three drive motors; and a transmission for transferring a drive force from each of the drive motors to the winch drum.

The skip hoist further relates to a blast furnace.

A lifting device includes a drive, a speed change gear device arranged above the drive and configured to be rotatable by means of the drive, a transmission device connected to the speed change gear device and a lifting mechanism fixed in the transmission device, and the speed change gear device is fixed to a side wall of the transmission device. Under an action of the drive and a speed change of speed change gear device, a gravity of a weight suspended on the lifting device is converted, so that the weight is lifted under a small force. The lifting device can also be driven via an electric hand tool. In addition, a first transmission device and a second transmission device are provided with a safety device to lock the lifting device when reaching a top, so as to prevent the lifting device from slipping to cause injuries.

A small, portable, powered winch that may employ a power drill or socket wrench.

A small, portable, powered winch that may employ a power drill or socket wrench.

The present invention is directed to a self-locking non-backdrivable gear system. The gear system may comprise a primary motor input and gear box. The primary motor input is for rotation of the gearbox about the axis of a drive shaft. The gearbox may comprise an input ring gear, one or more locking gears, fixed gear, and output gear. In operation, rotation of the primary motor input causes rotation of the ring gear which causes rotation of the locking gear which causes rotation of the output gear which causes rotation of the drive shaft. However, in the absence of rotation of the ring gear, a rotational force applied to the output gear causes the gear teeth on the fixed and output gears to lock the gear in place.

The present invention is directed to a self-locking non-backdrivable gear system. The gear system may comprise a primary motor input and gear box. The primary motor input is for rotation of the gearbox about the axis of a drive shaft. The gearbox may comprise an input ring gear, one or more locking gears, fixed gear, and output gear. In operation, rotation of the primary motor input causes rotation of the ring gear which causes rotation of the locking gear which causes rotation of the output gear which causes rotation of the drive shaft. However, in the absence of rotation of the ring gear, a rotational force applied to the output gear causes the gear teeth on the fixed and output gears to lock the gear in place.