Tool stocker, machine tool system, and tool damage detecting apparatus

A machine tool system comprising:

• a main spindle for supporting a tool detachably mounted thereon for machining a predetermined region of a workpiece in coaction with a turn arm;
• a first tool stocker for holding a plurality of tools to be detachably mounted on the main spindle, the first tool stocker being rotatable to index one of the tools at a time;
• a second tool stocker for holding a plurality of tools and transferring tools to and from the first tool stocker;
• and
• a tool transfer mechanism for transferring tools between the first tool stocker and the second tool stocker,
• wherein the main spindle has a turning center about which the main spindle is rotatable, the first tool stocker has a rotational center about which the first tool stocker is turnable, and the second tool stocker has a tool transfer position for transferring tools to and from the tool transfer mechanism, and
• wherein the turning center, the rotational center, and the tool transfer position are located in a substantially identical vertical plane.

A tool damage detecting apparatus in a machine tool system having a machining unit for machining a workpiece with a tool detachably mounted thereon and a plurality of tool stockers for storing a plurality of tools and transferring the tools to and from the machining unit, the tool stockers being rotatable to index the tools, the tool damage detecting apparatus comprising:

• a bracket having a plurality of tool approaching members for simultaneously approaching toward at least respective ones of the tools stored on the tool stockers;
• a plurality of contactless or contact-type detectors mounted respectively on the tool approaching members, for detecting damage to the tools;
• and
• a moving mechanism for moving the bracket in an axial direction of the tools.