Rotary motion can be converted into linear motion by using a screw. This volume introduces an automation clever mechanism that allows control of linear motion in various ways by adopting different types of screw structures. "Threaded" and "tapped" screws are used as a cam in this volume.

[Fig.1] is a diagram of the automation clever mechanism where two pieces of reversing screws are assembled onto a shaft.

If the handle installed on the right edge is rotated, it causes a linear motion of the slide block placed on the two tapped screws that are assembled to the opposing two screws. This structure can also be applied for a double-speed mechanism, where single rotation of the handle is transformed into a movement of twice the pitch of the rotation.

Application examples

[Fig.2] shown here has a different screw structure to [Fig.1].

Moving the shaft connected to the handle by one pitch can create differential motion from the slide block movement. In other words, single rotation of the handle will move the shaft the distance of screw pitches towards the left side. Simultaneously, the slide block moves the distance of screw pitches in the reverse direction of the shaft movement (towards the right side). Since the relative motion of the shaft and slide block here is equal to the difference (differential motion) of these two movements, precise adjustment on the movement is possible. A fine thread screw has been adopted for the slide block parts in [Fig. 2]. However, using a screw with the same pitch as the right one can still produce the fine movement because this mechanism works by the differential motion.

Application examples