Numerically controlled machine tool

A numerically controlled machine tool for machining a workpiece mounted on a workpiece support unit by moving a spindle having a tool mounted thereon in directions along an X-axis, a Y-axis and a Z-axis with respect to the workpiece, said machine tool comprising:

• a spindle support structure including a base adapted to be located on a floor surface and having guides extending in the direction along the X-axis on the upper and lower portions thereof, an X-axis slider guided along the guides on the upper and lower portions of said base to move from side to side in the direction along the X-axis, a Y-axis slider guided to move upwardly and downwardly in the direction along the Y-axis on said X-axis slider, a Z-axis slider guided to move forwardly and backwardly in the direction along the Z-axis on said Y-axis slider, and a spindle head mounted to be rotatable about at least a rotational axis extending in a direction along the Z-axis and a rotational axis perpendicular to a direction along the Z-axis;
• a workpiece support structure including a base having shaft support means located at the opposing ends thereof along the X-axis, and a workpiece mounting table supported by said shaft support means to allow for rotational indexing about a horizontal axis extending in the direction along the X-axis, said workpiece mounting table having at least one pallet mounting means for detachably mounting on said workpiece mounting table a pallet for attaching a workpiece thereon;
• a pallet changing means including a pallet stocker located adjacent to said workpiece support structure and a pallet carrier for transporting the pallet between said workpiece mounting table and said pallet stocker;
• and
• a chip discharge means located between said spindle support structure and said workpiece support structure for discharging chips produced in the machining area to the outside of said machining area,
• wherein said base of said spindle support structure has longitudinal spaces extending in the direction along the X-axis and opening downwardly in the upper and lower portions of said base, respectively, and each of said longitudinal spaces accommodates therein a guide for guiding and supporting said X-axis slider and an X-axis feed means for moving said X-axis slider in the direction along the X-axis.

A numerically controlled machine tool for machining a workpiece mounted on a workpiece support unit by moving a spindle having a tool mounted thereon in directions along an X-axis, a Y-axis and a Z-axis with respect to the workpiece, said machine tool comprises:

• a spindle support structure including a base adapted to be located on a floor surface and having guides extending in the direction along the X-axis on the upper and lower portions thereof, an X-axis slider guided along the guides on the upper and lower portions of said base to move from side to side in the direction along the X-axis, a Y-axis slider guided to move upwardly and downwardly in the direction along the Y-axis on said X-axis slider, a Z-axis slider guided to move forwardly and backwardly in the direction along the Z-axis on said Y-axis slider, and a spindle head fixedly mounted on said Z-axis slider or mounted to be rotatable in at least one of directions along an A-axis, a B-axis and a C-axis;
• and
• a workpiece rest disposed in the front of said spindle support structure for fixedly mounting a workpiece thereon,
• wherein said base of said spindle support structure is provided with longitudinal spaces extending in the direction along the X-axis and opening downwardly in the upper and lower portions of said base, respectively, the guide located in each of said longitudinal spaces for guiding and supporting said X-axis slider, and an X-axis feed means located along said guide in each of said longitudinal spaces for moving said X-axis slider.

A numerically controlled machine tool for machining a workpiece mounted on a workpiece support unit by moving a spindle having a tool mounted thereon in directions along an X-axis, a Y-axis and a Z-axis with respect to the workpiece, said machine tool comprising:

• a spindle support structure including a base adapted to be located on a floor surface and having guides extending in the direction along the X-axis on the upper and lower portions thereof, an X-axis slider guided along the guides on the upper and lower portions of said base to move from side to side in the direction along the X-axis, a Y-axis slider guided to move upwardly and downwardly in the direction along the Y-axis on said X-axis slider, a Z-axis slider guided to move forwardly and backwardly in the direction along the Z-axis on said Y-axis slider, and a spindle head mounted to be rotatable about at least a rotational axis extending in a direction along the Z-axis and a rotational axis perpendicular to a direction along the Z-axis;
• a workpiece support structure including a base having shaft support means located at the opposing ends thereof along the X-axis, and a workpiece mounting table supported by said shaft support means to allow for rotational indexing about a horizontal axis extending in the direction along the X-axis, said workpiece mounting table having at least one workpiece mounting surface;
• and
• a chip discharge means located between said spindle support structure and said workpiece support structure for discharging chips produced in the machining area to the outside of said machining area,
• wherein said X-axis slider of said spindle support structure is driven in the direction along the X-axis by linear motors disposed along said guides on the upper and lower portions of said base, respectively, and each of said linear motors includes a stator and a mover arranged on said base and said X-axis slider in opposed relation to each other so that an attraction force of said stator acting on said mover reduces the load in gravitational direction exerted on said guide of said X-axis slider.

A numerically controlled machine tool for machining a workpiece mounted on a workpiece support unit by moving a spindle having a tool mounted thereon in directions along an X-axis, a Y-axis and a Z-axis with respect to the workpiece, said machine tool comprising:

• a spindle support structure including a base adapted to be located on a floor surface and having guides extending in the direction along the X-axis on the upper and lower portions thereof, an X-axis slider guided along the guides on the upper and lower portions of said base to move from side to side in the direction along the X-axis, a Y-axis slider guided to move upwardly and downwardly in the direction along the Y-axis on said X-axis slider, a Z-axis slider guided to move forwardly and backwardly in the direction along the Z-axis on said Y-axis slider, and a spindle head mounted to be rotatable about at least a rotational axis extending in a direction along the Z-axis and a rotational axis perpendicular to a direction along the Z-axis;
• and
• a workpiece rest disposed in the front of said spindle support structure for fixedly mounting a workpiece thereon,
• wherein said X-axis slider of said spindle support structure is driven in the direction along the X-axis by linear motors disposed along said guides on the upper an lower portions of said base, respectively, and each of said linear motors includes a stator and a mover arranged on said base and said X-axis slider in opposed relation to each other so that an attraction force of said stator acting on said mover reduces the load in gravitational direction exerted on said guide of said X-axis slider.