Electric hoist is a commonly used light and small lifting equipment, widely used in factories, mines, warehouses, docks and other places, mainly used for lifting and loading and unloading materials. Its basic structure includes motor, reducer, transmission device, drum (or sprocket), lifting medium (wire rope or chain) and control system.
Basic composition
- Electric motor
The electric hoist uses a special lifting motor with strong starting torque and good overload capacity, and is usually equipped with an electromagnetic brake to achieve rapid stopping of the electric hoist.
- Reducer
The motor reduces the speed through the reducer, increases the output torque, and ensures a smooth and powerful lifting process. Reducers generally use closed gear boxes, which have smooth transmission and low noise.
- Drum or sprocket
- Wire rope hoists use a drum, on which the wire rope is wound, and the drum is rotated to achieve lifting and lowering.
- Chain hoists use a sprocket, and the lifting chain drives the load up and down through the rotation of the sprocket.
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Lifting medium
- Wire rope
- Lifting chain
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Control system
Includes button handle, remote control or control cabinet, the operator starts, stops, controls the lifting speed or reverse movement through control signals.
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Limit device
Prevent ultra-high or ultra-low operation and protect the safety of equipment and operators.
Overview of the working principle of electric hoist
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Lifting principle
When the electric hoist receives a control command, the motor starts and drives the reducer to work. The reduced power is output to the drum or sprocket, driving the wire rope or lifting chain to rotate, completing the raising or lowering of the load.
- Rising: The motor rotates forward → The drum or sprocket rotates forward → The lifting medium winds up (chain/wire rope) → The load rises
- Descending: The motor rotates reversely → The drum or sprocket rotates reversely → The lifting medium relaxes → The load descends
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Braking and holding
At the moment of stopping lifting or lowering, the electromagnetic brake automatically engages, reliably braking to prevent the load from sliding down and ensure the safety of the lifting operation.
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Limit control
The electric hoist is equipped with upper and lower limit switches. When the hook approaches the limit position, the limit switch will operate and automatically cut off the power supply to prevent the hook from exceeding the limit and ensure the safety of the equipment.
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Control method
- Button control: common hanging wire control method, easy to operate;
- Remote control: suitable for remote operation, improving safety;
- Linkage control: matched with bridge cranes and other equipment to achieve comprehensive control.
