The manual chain hoist belongs to a handy, easy-to-carry manual machine. The machine is mainly used for short distance lifting of small equipment and goods. The lifting weight is generally not more than 10t. In comparison, this kind of manual chain hoist has the characteristics of compact structure, small hand pull force and so on. The machinery is mainly composed of sprocket, hand zipper, transmission machinery, lifting chain and upper and lower hooks.
From the point of view of the compositional structure, in the manual chain hoist, the mechanical transmission part can also be divided into two types: worm gear type and gear type transmission. Among them, the mechanical efficiency of the worm gear drive is low and the parts are easy to wear. At present, it is rarely used. Gear transmissions are more and more widely used and include several different models. The structural principle of the lifting device can be understood as: a combination of a speed reducer with a reversed back brake and a chain pulley block.
The industrial fields covered by manual chain hoists mainly include factories, miners, agriculture, electric power, and construction. They are mainly used for production and construction, cargo lifting, and vehicle loading and unloading. Especially in the open air and without power supply, the product has played an important role. The utility model can not only be used alone, but also can be combined with various types of hand-drawn single-track traffic to form a hand-pulling and lifting transport vehicle so as to realize the function of walking and lifting a heavy object.
In general, as a manual, the mechanical and manual chain hoists are not only portable, but also have a lifting capacity of usually 0.5 to 50 tons and a lifting height of 30 meters. Its working methods can be divided into single-speed or double-speed lifting, suspension hooks or running cars with manual or electric, two-way or multi-directional operation.
At present, there are many high-quality manual chain hoists equipped with a number of protection devices at the same time, which makes its operation and use more secure. For example, an overload protection device is specially configured. This is a special protection device for the operator, the manual chain hoist itself and the load. When the load is greater than the set value, overload protection is automatically enabled and hoist hoist will automatically stop.