In July, Raymond J. Drago, P.E.—chief engineer of Drive Systems Technology, Inc. (DST), a mechanical power transmission consulting organization that he founded in 1976—will lead an IACET-accredited course on both the geometry and rating of involute splines of various types along with their applications. Topics under discussion include spline configuration variations, including half depth, full depth, and special function designs; both fixed and flexible spline configurations in terms of usage and design; lubrication methods, including grease, oil bath, and flowing oil, as well as coatings appropriate for various spline applications; and shear and compressive stress rating methods with analyses methodology in both equation and graphical methodology via various rating charts.
This article provides a guideline for the selection of a suitable standard in connection with the kind of spline to be designed and manufactured. Some basic formulae have been explained, together with a strategy on how to find standard
tooling by calculating an appropriate profile shift factor for the spline to be designed.
REANY is software for the evaluation of
gears and splines that have been measured
completely on all teeth. It is suited
to both quality assessment and analyzing
the causes for deviations. REANY is
short for Reality Analysis.
During a year with a strong
dollar, tanked oil prices and a
number of soft markets that
just aren't buying, one might
expect spline manufacturers
to be experiencing the same
tumult everyone else is. But when
I got a chance to speak with some of
the suppliers to spline manufacturers at
IMTS about how business is going, many
of the manufacturing industry's recent
woes never came up, and instead were
replaced by a shrug and an "eh, business
is doing pretty well."
A finite elements-based contact model is developed to predict load distribution along the spline joint interfaces; effects of spline misalignment are investigated along with intentional lead crowning of the contacting surfaces. The effects of manufacturing tooth indexing error on spline load distributions are demonstrated by using the proposed model.
Involute spline couplings are used to transmit torque from a shaft to a gear hub or other rotating component.
External gear teeth on the shaft engage an equal number of internal teeth in the hub. Because multiple teeth engage
simultaneously, they can transmit much larger torques than a simple key and keyway assembly. However, manufacturing
variations affect the clearance between each pair of mating teeth, resulting in only partial engagement.
Introducing backlash into spline couplings has been common practice in order to provide for component eccentric and angular misalignment. The method presented here is believed to be exact for splines with even numbers of teeth and approximate for those with odd numbers of teeth. This method is based on the reduction of the maximum effective tooth thickness to achieve the necessary clearance. Other methods, such as tooth crowning, are also effective.