Automatic tool changer

Claim 1

An automatic tool changer for a machine tool, comprising: a machine tool spindle; a tool magazine comprising a plurality of tool pots which form receptacles for holders fitted with tools, said tool pots being arranged at pre-determined intervals on an endless chain such that an axis of each said tool pot is parallel to the rotational axis of said spindle; first and second arms arranged in the vicinity of said machine tool spindle such that said spindle is positioned between said first arms and said second arms; each of said and first and second arms, respectively, being provided with tool gripping means at the outer end thereof nearest said machine tool spindle so as to be capable of separately performing a tool changing operation; first and second slide bases arranged, respectively, to be moveable in a direction perpendicular to the rotational axis of said machine tool spindle and alternately of said spindle and perpendicular to the axes of said tool pots, and wherein said first and second slide bases are operably coupled to supporting bases having guide bars; said slide bases being mechanically coupled to said first and second arms, respectively, as to cause corresponding movement of said arms; first and second rotary plates, respectively, pivotally mounted with respect to said first and second slide bases and mechanically coupled to said first and second arms, respectively, as to cause pivotal motion of said said first and second arms; first and second cylinder means, respectively, for actuating said first and second slide bases toward and away from each other along said guide bars; and third and fourth cylinder means, respectively, for actuating said first and second rotary plates.