Method and device for aligning a workpiece on a machine tool table

A device for automatically aligning a workpiece on a table of a machine tool, wherein the workpiece is fitted to a clamping fixture carried by said table to be machined by a machining head;

• said head and said table being movable with respect to each other along two coordinate axes;
• said workpiece comprising two locating pins, said fixture being provided with a locating member for clamping one of said pins, and with a pair of bars operable for clamping the other one of said pins;
• first actuator means for moving said locating member along said coordinate axes, second actuator means for moving one of said bars toward the other of said bars;
• a pair of locating elements provided on said workpiece, an optoelectronic sensor for determining the real position of each of said elements when said pins are so clamped, and a control circuit responsive to said sensor for controlling said first and second actuator means as to align said real position with a predetermined reference position.

A device for automatically aligning a workpiece on a table of a machine tool, wherein the workpiece is fitted to a clamping fixture carried by said table and is machined by a machining head;

• said head and said table being movable with respect to each other along two coordinate axes X, Y;
• characterized in that said workpiece is fitted to said fixture by means of clamping means movable on said fixture by means of actuators;
• a control circuit being provided to so control said actuators as to align said workpiece in a predetermined position said actuators are defined by electric motors;
• two of said motors moving said locating member along said two coordinate axes;
• a third of said motors moving said other bar along one of said coordinate axes X, Y;
• and said control circuit being able to control operation of said motors according to the respective distance components of said holes.

A device for automatically aligning a workpiece on a table of a machine tool, wherein the workpiece is fitted to a clamping fixture carried by said table and is machined by a machining head;

• said head and said table being movable with respect to each other along two coordinate axes X, Y;
• characterized in that said workpiece is fitted to said fixture by means of clamping means movable on said fixture by means of actuators;
• a control circuit being provided to so control said actuators as to align said workpiece in a predetermined position;
• said clamping member comprising a locating member and a pair of bars, said locating member being carried by a slide movable along one of said coordinate axes X, Y;
• said slide being guided by a shift member movable along a first inclined surface with respect to said coordinate axes X, Y;
• a first of said bars being movable along a second inclined surface with respect to said coordinate axes X, Y;
• and said inclined surfaces determining a component of movement of said locating member and said bar along the other of said coordinate axes X, Y.

A device for automatically aligning a workpiece on a table of a machine tool, wherein the workpiece is fitted to a clamping fixture carried by said table and is machined by a machining head;

• said head and said table being movable with respect to each other along two coordinate axes X, Y;
• characterized in that said workpiece is fitted to said fixture by means of clamping means movable on said fixture by means of actuators;
• a control circuit being provided to so control said actuators as to align said workpiece in a predetermined position;
• said actuators defined by at least two electric motors having shafts acting on said locating member by means of a screw-nut-screw coupling, said shafts of said two motors and said screws of said respective screw nut couplings running parallel to the direction of movement along a first incline surface with respect to said coordinate axis X, Y.

A device for automatically aligning a workpiece on a table of a machine tool, wherein the workpiece is fitted to a clamping fixture carried by said table to be machined by a machining head;

• said head and said table being movable with respect to each other along two coordinate axes;
• said workpiece being defined by a pack of printed circuit boards, each pack having two locating pins, said fixture being provided with a locating member for clamping one of said pins, and with a pair of bars;
• one of said bars being movable towards the other bar to clamp the other of said pins;
• said pack also comprising two locating holes adjacent to said pins;
• said machining head carrying an optoelectronic sensor for sequentially sensing said holes by means of a movement along one of said coordinate axes, said sensor being connected to an image processing circuit for determining the real position of the center of each of said holes and the distance between said real position and a corresponding reference position;
• said image processing circuit also determining the components of each distance along said coordinate axes;
• two electric motors for moving said locating member along said coordinate axes;
• a third electric motor for moving said other bar along one of said coordinate axes;
• and a control circuit adapted to control operation of said motors according to the respective distance components of said holes.