The Structure and Transmission Principle of Double Girder Overhead Crane

Double girder overhead crane has superior performance, compact structure, light weight, reliable and easy operation, and can meet various working conditions. It can reduce the overall investment of the plant, improve production efficiency, reduce maintenance costs, and save operating energy consumption.

1. The structure of double girder overhead crane

a. Bridge: It is composed of two main girders and two end beams and parts such as walkways and guardrails. There are two structural forms: box-shaped and truss;
b. Carriage running mechanism: It is composed of motors, brakes, reducers, couplings, transmission shafts, angle bearing boxes, wheels and other parts;
c. Hoisting trolley: It is composed of trolley frame, lifting mechanism and trolley running mechanism;
d. The lifting mechanism is composed of motors, brakes, transmission shafts, couplings, reducers, drums, fixed pulleys and wire ropes. It is divided into single brakes and double brakes;
e. Driver's cab: The place where the crane operator works. There are control equipment (interlocking table or cam controller), power distribution protection box, signal device and lighting equipment inside. The crane can only be started after the hatch is closed. This can avoid personal accidents when someone is working on the car or the driver has not entered the cab.

2.Transmission principle of double girder overhead crane
The movement of the general overhead crane is composed of three movements: the longitudinal movement of the trolley, the transverse movement of the trolley and the up and down movement of the hook.

a. Transmission of the lifting system: The power source of the lifting mechanism is generated by the motor, which is transmitted to the high-speed shaft end of the reducer through the gear coupling, compensation shaft, and brake wheel coupling. After the high speed of the motor is reduced to the required speed by the reducer, it is output by the low-speed shaft of the reducer, and the power is transmitted to the drum group through the inner gear ring on the drum, and then the hook is raised and lowered through the wire rope and pulley group, thereby completing the purpose of lifting heavy objects;
b. Transmission of the hoisting trolley operation system: The power is generated by the motor, and is transmitted to the high-speed shaft end of the vertical three-stage reducer through the brake wheel coupling, compensation shaft, and half-tooth coupling, and the motor is transmitted to the high-speed shaft end of the vertical three-stage reducer through the vertical three-stage reducer. After the high speed is reduced to the required b speed, it is output by the reducer low-speed shaft c, and then connected to the trolley driving wheel shaft through the half-tooth coupling, compensation shaft, and half-tooth coupling, thereby driving the rotation of the trolley driving wheel, completing the purpose of the trolley to transport heavy objects horizontally;
c. Transmission of the trolley running system: The power is generated by the motor, and transmitted to the high-speed shaft end of the reducer through the brake wheel coupling, compensation shaft and half-tooth coupling, and after the high speed of the motor is reduced to the required speed by the reducer, it is output by the reducer low-speed shaft, and then connected to the trolley driving wheel shaft through the full-tooth coupling, thereby driving the rotation of the trolley driving wheel, completing the purpose of the bridge frame to lift heavy objects longitudinally. The driving mechanism at both ends of the trolley is the same.