Connection knowledge and type of coupling

There are many types of couplings, according to the relative position and position changes of the two connected shafts, they can be divided into:

XNUMX. Fixed coupling.It is mainly used in places where two shafts require strict alignment and no relative displacement during work. The structure is generally simple, easy to manufacture, and the instantaneous speed of the two shafts is the same, mainly including flange couplings, sleeve couplings, and clamps Shell couplings, etc.

XNUMX. Removable coupling.It is mainly used where the two shafts are deviated or have relative displacement during work. According to the method of compensating displacement, it can be divided into rigid movable coupling and elastic movable coupling.Rigid movable coupling uses the dynamic connection between the working parts of the coupling to have a certain direction or several directions to compensate, such as jaw coupling (allowing axial displacement), cross groove coupling (Used to connect two shafts with small parallel or angular displacement), universal coupling (used in places where the two shafts have a large deflection angle or large angular displacement during work), gear coupling (allowed Comprehensive displacement), chain coupling (allowing radial displacement), etc., the elastic movable coupling (referred to as elastic coupling) uses the elastic deformation of the elastic element to compensate for the deflection and displacement of the two shafts. At the same time, the elastic element It also has cushioning and damping properties, such as serpentine spring couplings, radial multilayer leaf spring couplings, elastic ring pin couplings, nylon pin couplings, rubber sleeve couplings, etc.Some couplings have been standardized.

Couplings have double-end tooth profile, single-end tooth profile, jaw type, leaf spring type, disc spring, cross slide type and roller chain type.Because of the different types, some are lubricated with lubricating oil, and some are lubricated with grease.The main coupling of the steel mill rolling mill refers to the cross slide universal coupling. This coupling is an indispensable part of the rolling equipment and the working conditions are harsh.The semicircular connecting copper slider will work under severe impact load and high pressure (the deflection angle of the connecting rod is often greater than 120), therefore, the plane and arc surface of the slider will be severely worn.

The characteristic of the coupling is a bit like a bellows coupling. In fact, the way the coupling transmits torque is similar.The diaphragm itself is very thin, so it is easy to bend when the relative displacement load is generated, so it can withstand up to 1.5 degrees of deviation, while generating a lower bearing load in the servo system.Couplings are often used in servo systems. The diaphragm has good torque rigidity, but it is slightly inferior to bellows couplings.On the other hand, if it is misused in use or not installed correctly, it can easily be damaged.

Diaphragm couplings often encounter central alignment problems when machining keyways on vertical milling machines.In the past, we often used scribing, cutting mark observation and radius alignment.The diaphragm coupling is composed of at least one diaphragm and two shaft sleeves.The diaphragm is fastened to the shaft sleeve with a pin and generally does not loosen or cause backlash between the diaphragm and the shaft sleeve.Some manufacturers provide two diaphragms, and some provide three diaphragms, with one or two rigid elements in the middle, and the two sides are connected to the shaft sleeve.Standard couplings with different torque, speed and working conditions can basically be achieved in different structural types and specifications.

In the selection process, many different performance factors are included, including torque, shaft deviation, hardness, speed, space requirements, etc. The coupling needs to achieve all of these in order for the system to operate normally.When choosing a coupling, the designer should first choose from the couplings that have been formulated as standards, machinery industry standards, and obtained. Only when the existing standard couplings and couplings cannot meet the design requirements, they can design the coupling by themselves. Device.The deviation of the center line is large, and the processing quality cannot be achieved.