Sliding feed mechanism having worm gear

摘要

An improved sliding feed mechanism having a worm gear is disclosed can prevent a locking state from occurring between the worm and the worm wheel. The sliding feed mechanism includes a motor having a rotational shaft with an output end, a worm fixedly mounted to the rotational shaft and formed with a left-hand thread, a worm wheel which meshes with the worm, a driven member which is adapted to slidably move according to the rotation of the worm wheel. In this connection, the lead angle of the worm wheel is set so as to be larger than the lead angle of the worm, and the motor is mounted so that the output end of the rotational shaft is upwardly tilted so as to provide a proper engagement between the worm and the worm wheel having said lead angle.