Drilling system with stationary work table

A drilling system, comprising:

• a stationary base table for supporting a plurality of work pieces under process at respective fixed positions at a drilling spindle station;
• a plurality of drilling spindles each for carrying and applying rotational force to a drilling tool, the respective drilling spindles including a Z-axis drive system for applying reciprocating movement along a Z-axis to the drilling tool;
• a compound overhead guiding system that carries the plurality of spindles above the work piece under process, said system including a Y-axis guiding structure for guiding movement of the spindles along a Y axis in relation to the base table, and an X drive system for driving the spindles along an X axis which is orthogonal to said Y axis;
• said guiding system comprising a lightweight crossbeam structure for carrying the spindle and X axis drive system, said crossbeam structure comprising a laminated assembly comprising a first hollow structural element having high torsional strength and a second hollow structural element having high bending strength.

A low impact pressure foot system for a drilling spindle for applying a clamping force against a surface of a work piece during a drilling stroke, the pressure foot system comprising:

• a body structure which remains in a stationary position during each drilling stroke relative to the work piece;
• a movable clamp member carried by the body structure;
• a sensor for detecting and generating a sensor signal indicative of a close proximity or contact condition of the movable clamp member relative to the surface of the work piece;
• and
• an actuator system for moving the movable clamp member toward the surface of the work piece under a low impact force until the clamp member comes into contact with the surface of the work piece, and in response to said sensor signal, while holding the clamp member in a substantially stationary position relative to the surface of the work piece, applying a clamp force greater than said low impact force with the clamp member against the surface of the work piece during a drilling stroke, and for moving the clamp member away from the surface at the end of a drilling stroke.

A low impact pressure foot system for a drilling spindle for applying a clamping force against a surface of a work piece during a drilling stroke, the pressure foot system comprising:

• a body structure which remains in a stationary position during each drilling stroke relative to the work piece;
• a movable clamp member carried by the body structure, wherein the clamp member is a relatively low mass finger element having an opening formed therein to allow passage of the drill bit during a drilling stroke, said finger element hingedly connected to the body;
• and
• an actuator for applying a clamp force to move the clamp member against the surface of the work piece at commencement of a drilling stroke and moving the clamp member away from the surface at the end of a drilling stroke.

A low impact pressure foot system for a drilling spindle for applying a clamping force against a surface of a work piece during a drilling stroke, the pressure foot system comprising:

• a body structure which remains in a stationary position during each drilling stroke relative to the work piece;
• a movable clamp member carried by the body structure;
• and
• an actuator for applying a clamp force to move the clamp member against the surface of the work piece at commencement of a drilling stroke and moving the clamp member away from the surface at the end of a drilling stroke, wherein the actuator comprises a pneumatic valve and an inflatable bladder element, the valve for selectively inflating and deflating the bladder element to apply the clamp force.

A low impact pressure foot system for a drilling spindle for applying a clamping force against a surface of a work piece during a drilling stroke, the pressure foot system comprising:

• a body structure which remains in a stationary position during each drilling stroke relative to the work piece;
• a movable clamp member carried by the body structure;
• an actuator for applying a clamp force to move the clamp member against the surface of the work piece at commencement of a drilling stroke and moving the clamp member away from the surface at the end of a drilling stroke;
• and
• a Z-axis actuator for moving the pressure foot body along the Z-axis relative to the spindle to position the pressure clamp member at a position spaced by a distance from the work piece surface during a work piece drilling sequence.

A drilling system, comprising:

• a stationary base table for supporting a work piece under process at a fixed position at a drilling spindle station;
• a drilling spindle for carrying and applying rotational force to a drilling tool;
• a compound overhead guiding system that carries the spindle above the work piece under process, said system including a Y-axis guiding structure for guiding movement of the spindle along a Y axis in relation to the base table, an X drive system for driving the spindle along an X axis which is orthogonal to said Y axis, and a Z axis drive system for driving the drilling tool along a Z axis which is orthogonal to said X and Y axis;
• said guiding system comprising a lightweight crossbeam structure for carrying the spindle and X axis drive system, said crossbeam structure comprising a laminated assembly having a high stiffness-to-weight ratio in relation to a cast iron crossbeam construction.