Shaft rotation control

 The simplest total shaft rotation control is with a key or with a pin fixing the shaft. In partial rotation control the shaft is limited to rotate within a certain angle by means of a peripheral slot and a dog point set screw. The length of the slot on the perimeter sets the rotation angle of the shaft. The end of the set screw mates with the peripheral slot and blocks the shaft rotation at the slot’s ends (see figure above). This kind of control is mainly a back-up, a safety when the shaft rotates beyond the functional limits. It can be used for manual operation in order to prevent excessive rotation angle from the user, is useful especially with manual clamping when the rotation angle increases the clamping force (wedge type, cam actuated, etc).