Views:39 Author:Site Editor Publish Time: 20-07-2018 Origin:Site
The lifting mechanism of crane is composed of a driving device, a transmission device, a winding system, a take-up device, a brake and other safety devices. Different types of cranes need to be equipped with different taking devices, and the driving devices are also different, but the arrangement is basically the same.
When the lifting weight exceeds 10t, the two lifting mechanisms are standing: the main lifting mechanism and the auxiliary lifting mechanism. Under normal circumstances, the two organizations can work separately, and in special cases, they can work together.
1. Drive unit. Most cranes are motor driven and easy to arrange, install and service. Mobile cranes (such as truck cranes, tire cranes, etc.) are powered by internal combustion engines, and the transmission and control systems are more complicated.
2. Transmission. Including reducer, coupling and drive shaft. The reducer is usually a closed horizontal standard two-stage or three-stage cylindrical gear reducer. The crane of larger capacity, sometimes we can add a pair of open gears to obtain low speed and large torque. In order to compensate the influence of the elastic deformation of the trolley frame on the working reliability of the mechanism, the elastic pin coupling or gear coupling with compensation performance is usually adopted.
3. Winding system. It refers to the reel and wire rope pulley block. The bridge type crane adopts a double pulley block, and the single pulley block is generally used for a boom type crane.
4. The fetch device. It adopts different kinds of fetch devices according to the type and shape of the suspended materials. There are many kinds of equipment to take things, the biggest use is the hook.
5. Brakes and safety devices. The brake is not only the control device of the mechanism, but also the safety device. The brake of the lifting mechanism must be normally closed. Generally, the lifting mechanism of a crane is only equipped with one brake, which is usually mounted on a high speed shaft to carry hot metal or other dangerous goods, as well as the lifting mechanism which may cause serious danger or loss in the event of an accident. Each independent driving device should be equipped with two sets of supporting brakes.