Don't know a lot about cranes, ask a very crude question. What is the difference between a manual crane and an electric crane? Is it just the motivation needed? Is there any difference between the structure and the principle? Does manual electric heavy machine have to depend on human ability to work just like that simple chain gourd? It wouldn't be unreasonable if the height was too high. It is true that the cranes are not known, and the cranes are electric, except that the simple gourd has not seen any other manual lifting equipment. I look forward to some help with the picture. Let's make people laugh.
Manual is to rely on the pulley of electromotive pulley to be driven by the hydraulic cylinder to push if the distance asks big also need to add the pulley!
The theory is that motivation is different. As for what you say, "it's not unreasonable to be too tall," the problem is not too difficult to solve. Although I didn't design a manual crane, the lifting device for this crane would have a self-locking device. People raise the goods to a certain height, and when they are tired, they can rest and the goods will not fall on their own
Manual refers to the operation of the crane, crane hoisting mechanism all work are done by manpower, typically by chain drive, use the big chain wheel drive, to achieve the effect of energy. Manual double beam and single beam crane now have standard products, so you can use the Internet.
