Crane Hoisting Structure and Working Principle of Truck Crane

The role of the hoisting mechanism of the truck crane is to achieve the lifting and lowering of heavy objects and the free stop of the air. According to the crane capacity, the maximum lifting capacity of 8T and below is usually used by ordinary winch mechanism consisting of motor, gearbox, reel, etc. The crane with maximum lifting capacity above 10T uses motors and brakes. Hydraulic winches consisting of gear boxes, reels, and related valve groups (To increase product reliability and enrich product configurations, winches are currently available for 6.3T and above).

Lifting: The motor rotates clockwise to transmit torque and motion to the large gear in the reducer. The large gear and the gear shaft are connected with the left thread. The clockwise rotation of the motor input makes the gear rotate counterclockwise; the left thread makes the big gear. Move to the right axially, press the friction plate, ratchet wheel and brake disc; the brake disc transmits torque to the gear shaft through the key, so as to drive the large ring gear and the reel on the reel to rotate clockwise, and realize the wire rope and the pulley block. The lifting of the hook. Pawls do not work during this process.

Falling: The counter-clockwise rotation of the motor rotates the counterclockwise gear, the left-hand thread moves the bull gear to the left, and the large gear, friction plate, ratchet, and brake disc disengage from each other to create a certain clearance. The heavy object makes a free fall to make the reel and large The ring gear rotates clockwise. When the rotation speed of the gear shaft and the brake disk is equal to the motor rotation speed, each piece of the friction plate is in a critical state of compression, and the speed of the weight drop exceeds the speed of the motor transmission, and the mechanism generates a brake; the motor Continue to turn to open the friction, the weight began to fall again, so that repeated, so that the weight of the smooth landing on the ground. In this process, the pawl is combined with the ratchet, and the ratchet is stationary.

Stop: If the weight is in any position in the air, as long as the rotation of the motor is stopped, the clearance at the friction plate will be eliminated by the motion generated during the falling of the weight. At this time, the ratchet is suppressed and the gear shaft has a tendency to rotate clockwise due to spines. The action of the claw causes the mechanism to stand still and the weight falling motion is braked.

The hydraulic winch reducer is a planetary gear structure, compact, and it is built into the drum inside the drum. The brake is normally closed, always holding the reel; when the reels need to be rotated, the control valve is operated and the reel can be rotated while the brake is opened by the shuttle valve. In order to ensure the smoothness and reliability of the operation, hydraulic winches are usually equipped with bidirectional balancing valves, overload valves, and the like. Therefore, the performance of the hydraulic winch is better than the ordinary winch mechanism, but due to the high cost, its application range is subject to certain restrictions. Want to know more information about truck crane and contact with truck crane?