What is Spline Shaft?
Splines are ridges or teeth on a drive shaft that mesh with grooves in a mating piece and transfer torque to it, maintaining the angular correspondence between them. For instance, a gear mounted on a shaft might use a male spline on the shaft that matches the female spline on the gear.
Types of Spline Shaft:
There are lot of spline shafts used currently; here are some of them-
(1) Parallel:
Parallel spline shaft would have ridges or teeth that have a square profile.
(2) Involute:
This kind has tapered ridges along the shaft, which help in lowering the stress concentrations during gear operation.
(3) Crowned:
These kinds of spline shaft have specially designed teeth that taper or smoothen out towards the end face of the spline. This allows for angular misalignment during gear operation.
(4) Serrations:
Serrations have a non-involute tooth designed spline. The said gear splines would be set at an angle allowing for more teeth to be set on the shaft itself.
(5) Helical:
This kind of spline shaft would either have parallel or involute splines where the ridges form a helix pattern across and around the shaft itself.
Functions of a Spline Shaft:
The basic operation of a spline shaft is to mate with a female version of it, or interlock in order to transfer rotary movement. Another function is to become a linear guide when working with a bearing with internal spline gear mechanism. The key element would be the interaction and interlocking of the gears and the shaft. An example would be a gear mounted on a shaft would have female splines which interlock with male splines on the shaft.
Measurement method:
Major-diameter fits tend to centre the spline connection between the external and internal parts by the major diameter and the outside diameter. Actual tooth thicknesses and space widths are those for an individual spline tooth and are typically measured by over- or between-pin measurements.
Reference Links:
https://true-gear.com/the-workings-of-a-spline-shaft/blog.html