Ball spline (shaft) is an innovative linear motion system. Its precise linear motion and torque transmission are realized by ball. In addition, the biggest difference between ball spline (shaft) and ordinary spline is that it can preload a single nut. Therefore, this kind of spline can better adapt to special requirements, such as vibration, load impact, high-precision positioning, high-speed movement, etc. The ball spline has two rows of balls, presentedone hundred and eighty° symmetrically distributed to ensure accurate movement of spline shaft nut.

1、 Structure and characteristics
oneHigh torque transmission
There are two semi-circular grooves on the ball spline (shaft) that have been ground and can match with the ball. When the torque is applied to the spline shaft or nut, the two rows of balls can automatically adjust the rotation center and evenly distribute the torque.
two, high load, long life
The ball spline (shaft) has the performance of linear bearing, and can also bear high radial load and other loads. The spline shaft is not only compact, but also has reliable safety and long service life under the conditions of high load and high torque.
three. zero clearance
The ball spline (shaft) minimizes the clearance (angular clearance) in the direction of rotation. If necessary, the angular clearance can be adjusted to zero by preloading the nut, so as to improve the overall rigidity of the ball spline.

2、 Precision
The machining accuracy of the knurled key (shaft) meets the requirements ofJIS B1193Standards. It is divided into three levels - normal (unmarked) and advanced（H）And precision grade（P）。 The accuracy grade is included in the model. The table also includes the accuracy grade of shaft end machining and the accuracy query of other special requirements.

3、 Preload
When high rigidity and precise positioning in rotation direction are required, the spline needs preload, and the average preload value is1/2~1/3However, the selection of preload value should also consider the service life of spline shaft under vibration or pulse load, especially the high rigidity factor.
The preload borne by the spline is calculated according to the radial load. If the preload exceeds the high preload value, please contact us.

4、 Precautions for use
oneThe maximum bearing ambient temperature of the knurled bead key (shaft) isone hundred and twenty℃, the maximum operating ambient temperature isone hundred℃, if more thanone hundred℃, please ask our company for model selection.
twoThe knurled key (shaft) can achieve high accuracy by adjusting the fit between the nut and the shaft. When the spline is installed and used, pay attention to the rotation direction and sliding direction of the nut and shaft.
threeUsed on one shafttwoWhen there are two or more nuts, they need to be used in the rotation direction of external fixationtwoFor one or more keys, the position of the keyway on the nut should be parallel.

5、 Assembly
one、 coordination
The nut and mounting hole of the knurled key (shaft) use interference fit（J7）, if the accuracy and rigidity requirements are not high, clearance fit can be used（H7）。
twoInstallation
When the spline nut is installed to the mounting hole, please use the special tool to avoid the nut deformation and poor operation.
When installing the spline shaft into the spline nut, in order to prevent the ball in the nut from falling off, please first confirm that the position of the ball groove on the shaft, the ball in the nut and the seal guide on the nut are correct.