Reading volume:17 发表时间:2019/9/20 8:39:10
Today's sprocket manufacturers share: Gear machining benchmark positioning, friends who want to know this topic, come and understand together with the editor:
Gear machining datum positioning, the accuracy of the positioning datum has a direct influence on the tooth profile machining accuracy.Tooth profile processing of shaft gears generally choose hole positioning, and for some large-modulus shaft gears, gear journals and one end face positioning are mostly selected.Two types of positioning datums are often used for tooth profile processing of disc sleeve gears.
1. Inner hole and end face positioning, gear processing selects the inner hole which is not only the design reference but also the measurement and assembly reference as the positioning reference, which not only conforms to the principle of "reference overlap", but also makes the process reference such as tooth profile processing uniform, as long as the inner hole is strictly controlled. Hole accuracy does not need to be aligned when positioning on a dedicated mandrel.Therefore, the productivity is high, and it is widely used in batch production.
2. The outer circle and end face are positioned. The inner hole of the gear blank is installed on the universal mandrel. The outer circle is used to determine the core position of the hole. Therefore, the radial runout of the outer circle of the tooth blank to the inner hole is required to be small.Due to low alignment efficiency, it is generally used for single-piece small batch production.
What can be done to increase the service life of the sprocket?
1. The tightness of the sprocket should be suitable. Too tight will increase power consumption and the bearing will wear out easily; if the sprocket is too loose, the sprocket will simply jump and unchain.The tightness of the sprocket is: lifted or pressed down from the middle of the sprocket, about 2%-3% of the core distance between the two sprocket.
2. The sprocket should not swing or tilt when installed on the shaft.In the same transmission assembly, the end faces of the two sprockets should be in the same plane. When the core distance of the sprocket is less than 0.5 meters, the error can be 1 mm; when the core distance of the sprocket is more than 0.5 meters, the error can be 2 mm.But there can be no conflicting sprocket tooth side phenomenon. If the two wheels offset too much, it will simply cause chain disconnection and accelerated wear.It is necessary to pay attention to check and adjust the offset when replacing the sprocket.
3. When the sprocket is very severely worn, it should be replaced with a new sprocket and a new chain at the same time to ensure good meshing.It cannot be replaced with a new sprocket or a new sprocket alone.Otherwise, poor meshing will form and accelerate the wear of the new sprocket or new sprocket.After the tooth surface of the sprocket wears to a certain degree, it should be turned over and used in time (referring to the sprocket with adjustable surface) to extend the use time.
4. The new sprocket is too long or stretched after use, which is difficult to adjust. You can remove the chain link depending on the situation, but it must be an even number.The chain link should pass through the reverse side of the sprocket, the locking piece should be inserted outside, and the opening of the locking piece should face the opposite direction of rolling.
5. The sprocket should be filled with lubricating oil in time during work.It is necessary for the lubricating oil to enter the cooperation gap between the roller and the inner sleeve to improve working conditions and reduce wear.
6. The old sprocket cannot be mixed with part of the new sprocket, otherwise it will simply cause an impact in the transmission and pull the sprocket.
7. When the machine is stored for a long time, the sprocket should be removed and cleaned with kerosene or diesel, and then coated with oil or butter and stored in a dry place.