Spline Shaft Mounting
Splines are an excellent way to transmit torque and centre a gear for high power applications. They are used in automatic transmissions, in couplings between engines and gearboxes, and in machine tools where it is important to have concentricity and low amounts of slop in the system. Spline shafts can be made with many of the same processes as gears, including milling, shaping, grinding, and rolling. They can also be injection molded.
Involute Splines
Involute splines use the same shape as an involute gear tooth, which has a few key advantages. First, the angled sides of the teeth centre the spline shaft in the mating part, improving the accuracy of the joint. Second, the smooth profile and radii of the involute form reduce the stress concentrations that parallel key splines experience. Involute splines are an excellent choice in high speed or low noise applications.
Parallel Key Splines
Parallel key splines have radial flanks and circular faces at the top and bottom of the spline tooth. This means that they do not self-centre and if the corners are not relieved, they will have higher stress concentrations than involute splines.
Ball Splines
To minimize friction as the internal spline coupler moves along the shaft, ball splines use recirculating balls as the contact elements in a similar fashion to ball bearings.
Common Spline Profiles | Ball Spline- allows smooth linear movement | |
---|---|---|
Splines used to transmit power to the spindle, which moves axially, in a Bridgeport milling machine. |
Keyed Shaft Mounting
References
Spline / mill pic https://www.practicalmachinist.com/vb/cincinnati-milacron-kearney-trecker-vn-usa-heavy-iron/famco-100-vertical-mill-pancake-motor-vfd-cold-start-problems-344262/
Splines 1 -https://true-gear.com/splined-shafts-versus-keyed-shafts/blog.html
Splines 2 - https://gearsolutions.com/features/side-fit-spline-profiles/
Parallel Key Spline - https://www.perrygear.com/machining-services/broaching
Press Fits https://www.assemblymag.com/articles/93984-best-practices-for-press-fit-assembly
Press Fits 2 / set screws https://gearsolutions.com/departments/tooth-tips/tolerances-associated-with-gears/
Taper Lock Bushings - https://shop.sdp-si.com/catalog/?brand=sdp&cid=p849
tolerances - https://gearsolutions.com/departments/tooth-tips/tolerances-associated-with-gears/
tapered - http://www.m1-seiko.co.jp/craftsmanship_taper_e.html