Spline shaft knowledge
(1) Introduction to spline connection
In mechanical transmission, a spline connection is formed by a spline shaft and a spline hole. The spline connection is a coaxial coupling that transmits torque and motion. It is a connection form that can transmit large torque and high centering accuracy. In the gearboxes of machine tools, automobiles and other machinery, most of them use the slip of the spline gear sleeve and the spline shaft as the variable speed transmission, and its application is very wide.
Among splines, according to different tooth profile shapes, they can be divided into rectangular splines and involute splines. Among them, the tooth profile of rectangular splines is rectangular, which is easy to process and more widely used. There are three methods for the centering of the rectangular spline connection (the limit of the position of the working axis of the spline pair): inner diameter centering, outer diameter centering, and key side centering.
A large number of external splines (spline shafts) are processed on a spline milling machine with a spline hob according to the generative principle. This processing method has high machining accuracy and productivity, but it must be equipped with a spline milling machine and a spline shaft. Key hob. In the case of single-piece, small-batch production or lack of special equipment such as spline milling machines, the indexing head is often used on the milling machine for clamping and indexing and milling of rectangular splines.
(2) Machining method of rectangular tooth spline
Milling of spline shafts with a milling machine is mainly suitable for single-piece production or maintenance. It is also used for rough machining of rectangular spline shafts centered on the outer diameter and rectangular spline shafts centered on the key side. This type of spline shaft The outer diameter or key side accuracy of the shaft is usually guaranteed by grinding. There are two main methods for milling the side of the spline shaft key on the milling machine: the three-face milling cutter milling method and forming milling cutter milling method. Forming milling cutters are difficult to manufacture, so under normal circumstances, three-face milling cutters are often used to mill the key side. Milling can be divided into single-cut milling and combined milling cutter milling.
When the precision of the key side is high and the number of spline shafts is large, the key side can be milled by the cemented carbide combination milling cutter. There are two sets of milling cutter heads on the cemented carbide combined milling cutter head, each set of two, one of which is used for milling the key side, and the other is used for chamfering both sides of the spline. The left and right tooth shoulder distance and the center position of each set of knives can be adjusted according to the key width or the size and position of the spline chamfer.