In American National Standard ANSI B92.1-1970 (R 1993), many features of the 1960 standard are retained plus the addition of three tolerance classes, for a total of four. Involute splines have maximum strength at the base, can be accurately spaced and are self-centering, thus equalizing the bearing and stresses, and they can be measured and fitted accurately. The internal spline is held to basic dimensions and the external spline is varied to control the fit. The general practice is to form the external splines either by hobbing, rolling, or on a gear shaper, and internal splines either by broaching or on a gear shaper. These splines or multiple keys are similar in form to internal and external involute gears. Involute Splines American National Standard Involute Splines *. Splines having straight-sided teeth have been used in many applications (see SAE Parallel Side Splines for Soft Broached Holes in Fittings) however, the use of splines with teeth of involute profile has steadily increased since 1) involute spline couplings have greater torque-transmitting capacity than any other type 2) they can be produced by the same techniques and equipment as is used to cut gears and 3) they have a self-centering action under load even when there is backlash between mating members. Splined shafts are most generally used in three types of applications: 1) for coupling shafts when relatively heavy torques are to be transmitted without slippage 2) for transmitting power to slidably-mounted or permanently-fixed gears, pulleys, and other rotating members and 3) for attaching parts that may require removal for indexing or change in angular position.
The latter construction weakens the shaft to a considerable degree because of the slots cut into it and consequently, reduces its torque-transmitting capacity.
A splined shaft is one having a series of parallel keys formed integrally with the shaft and mating with corresponding grooves cut in a hub or fitting this arrangement is in contrast to a shaft having a series of keys or feathers fitted into slots cut into the shaft.
0 kommentar(er)
