As a type of cardan drive shafts, the cross shaft type cardan drive shafts uses the characteristics of its mechanism to make the driving shaft and the driven shaft not on the same axis and realize the continuous rotation of the connected two shafts when there is an angle between the axes, and Can transmit torque and motion.
Compared with ordinary drive shafts, the important feature of cardan drive shafts is that the structure of cardan drive shafts has greater angular compensation capability, compact structure, and good transmission efficiency.
With its own performance, its market sales are considerable, and many types of universal couplings have appeared on the market. So how do you choose the right coupling?
Among them, the cross shaft type cardan drive shafts is a universal coupling with a large amount of consumption. The bearing of this universal coupling is a part that is easily damaged.
Generally speaking, cars will use ball cage universal couplings. For agricultural machinery, industrial machinery, and other sports machinery, universal couplings will be used. Most of the lifting and universal couplings will use cross shaft cardan drive shafts.
1. Preparation before hot-packing
Fill and scrub the shaft and cross shaft universal coupling with gasoline or kerosene. If there is roughness or damage, it needs to be solved with an oilstone or fine diamond gauze, of course, other methods can also be used.
Then use a micrometer to measure the inner diameter of the journal, and a micrometer to measure the inner diameter of the cross shaft universal coupling.
When measuring the coupling, at least 3 points must be measured and repeated measurements. If the processing result does not meet the requirements of the drawing, the inner hole should be repaired with a scraper or semicircular file.
2. hot pack
After the preparation work, start the hot assembly, which needs to be fast, so as not to complete the hot assembly, the temperature will drop, resulting in the narrowing of the aperture of the universal joint of the cross shaft type, which makes the hot assembly difficult.
Generally, the hot-swappable cross shaft type cardan drive shafts will heat the temperature to 250℃. The heating temperature should not be too fast, so as not to affect the uniformity of the temperature of the coupling, and the heating time should be determined according to its expansion.
In order to obtain a reasonable inner diameter of the coupling, a measuring stick of the same size can be made according to the measured expansion value of heating, and heated until the measuring stick can be put into the inner diameter hole. Then carry out hot set work.
The surface of the cross universal coupling should be carburized and quenched or tempered. The hardness of the surface obtained is different according to the method.
Gas carburizing The workpiece is loaded into a closed carburizing furnace, and a high-carbon surface layer is obtained by gas or liquid carburizing agent.
Solid carburization is to place the workpiece and solid carburizing agent (charcoal plus accelerator) in a sealed box, heated to a carburizing temperature in a heating furnace, and maintain it for a period of time to make the activated carbon universal coupling atomic infiltration This is also the carburizing method on the surface of the workpiece.
It is a universal component of the mechanical foundation, which is suitable for two shafts with even axis deflection and relative position often changing.
The advantage of the cross shaft type universal coupling is that it transmits large torque, has angle compensation capability and has a compact structure.
3. Principle of structure
The cross member on the main and driven shafts and the middle cross shaft are respectively connected by hinges. When there is the angular displacement between the two shafts, the shaft forks rotate around their respective fixed axes, so that the cross shaft moves in space.
4.motion analysis
When the inter-axis angle between the two axes is not zero, the actual rotation angle of any instantaneous driving shaft angle and driven shaft angle:
the plane comes from the driving shaft and is the motion plane on the driving shaft fork, the plane is perpendicular to The moving shaft is the movement of point C on the driven shaft fork.
