Manual feed device in wire electric discharge machine

Abstract

A manual feeding device in a wire electric discharge machine in which selection between a jog feed and a step feed is made automatically without mode change. When an axis motion key is pressed, a timer measures the time for which the key is pressed. When the key is turned off before the time measured reaches a predetermined length of time on the basis of which switching to the jog feed is made, the step feed is performed, so that the axis is moved by a predetermined amount. When the key is pressed for the length of time predetermined for switching to the jog feed, the jog feed is started, so that the axis is moved at a low speed. Further, when the key is pressed for a length of time predetermined for switching to a medium speed, the feed axis is moved at the medium speed, and when the key is pressed for a length of time predetermined for switching to a high speed, the axis is moved at the high speed. Since selection between the step feed and the jog feed and selection of the jog feed speed are automatically made depending on the time for which an axis motion key has been pressed, manual feeding operation to move a table and an upper guide is performed easily, so that the positioning of the table and the upper guide is performed easily.

Dependencies are inferred from the claim text.