A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium. The most familiar form is an elevator, the car of which is raised and lowered by a hoist mechanism. Most hoists couple to their loads using a lifting hook.
Electric hoist is a kind of special lifting equipment. It is installed on the crane and gantry crane. The electric hoist has the characteristics of small size, light weight, simple operation and convenient use. It is used in industrial and mining enterprises, storage, docks and other places.
The electric hoist is compact, and the electric hoist whose motor axis is perpendicular to the spool axis adopts a worm gear transmission. The disadvantages are: large length, large size in width, stupid structure, low mechanical efficiency, and difficult processing. The hydraulic system is dual-controlled, and the overflow control valve and magnetic contact pressure gauge can precisely control the pressure. The electrical control department uses low voltage control to increase the safety of the dominant system.
The lifting weight is generally 0.3 to 80 tons, and the lifting height is 3 to 30 meters. It consists of electric motor, transmission mechanism and reel or sprocket. It is divided into electric wire hoist and electric chain hoist. The electric chain hoist is divided into imported and domestic; the electric rope hoist is divided into single speed and double speed;