Change device, fine hole electric discharge machine and electrode change method

A fine hole electric discharge machine, comprising a first change device, a second change device, a first electrode collecting device and a second electrode collecting device, wherein the first change device, comprising:

• automatic electrode supply devices each comprising an electrode cartridge storing a plurality of electrodes of a predetermined diameter and an electrode feeder device supplying the electrodes one by one from the electrode cartridge;
• wherein the electrode feeder device includes a delivery tube housed in a housing so as to be movable in the vertical direction, a cushion pad provided at the top of the delivery tube, a compression coil spring pressing the delivery tube upward, a lock ring provided below the housing, and a notch provided between the lock ring and the compression coil spring;
• wherein the electrode cartridge is attached to an upper portion of the housing coaxially with the delivery tube;
• the electrode is delivered from the electrode cartridge by a case pusher cylinder provided on a side of machining main spindle, which moves the delivery tube in the vertical direction;
• a first magazine accommodating, in a detachable manner, the automatic electrode supply devices storing the electrodes of different diameters;
• and
• a first transfer device configured to transfer the automatic electrode supply devices from the first magazine to a fine hole electric discharge machine;
• wherein the first magazine comprises a circular magazine table that is controlled to indexably rotate and a plurality of accommodation members arranged at predetermined intervals on an outer circumference of the magazine table;
• each of the accommodation members comprises an upper accommodation member, a central accommodation member, and a lower accommodation member;
• the upper accommodation member, the central accommodation member, and the lower accommodation member are vertically aligned and each have a concave portion supporting the automatic electrode supply devices;
• wherein the upper accommodation member is a member to prevent the automatic electrode supply device from tilting in a pitch direction;
• wherein the lower accommodation member comprises ball plungers, the ball plungers engage a groove provided on a side surface of the automatic electrode supply device;
• and
• each of the automatic electrode supply devices is fixed by engaging with the lower accommodation member,
• wherein the second change device comprises a second magazine accommodating electrode holders in a detachable manner and a second transfer device configured to transfer the electrode holders between the second magazine and a second chuck provided on a tip portion of a machining main spindle, and
• the second magazine accommodates a plurality of electrode holders holding the electrodes of different diameters,
• wherein the first electrode collecting device is provided below a position of a machining head during machining;
• and
• the second electrode collecting device is provided below the second change device and collects the electrode having an electrode length of a predetermined value or more.