Drill head guiding control for multiple drills

A drill head guiding control for multiple drills comprising, in combination:

• a. a base frame supporting an elongated work surface;
• b. a cylindrical torque tube having an axis parallel to the plane of said work surface and to a straight line passing through a series of holes to be simultaneously drilled through material positioned on said work surface, said torque tube being mounted on said base frame for rotation about said axis;
• c. an elongated head member supporting a series of drills aligned in side-by-side relationship in a direction parallel to said axis;
• d. first and second guide rails secured to said base frame in parallel relationship normal to said work surface and spaced apart in a direction parallel to said axis;
• e. first and second rail engaging means secured respectively adjacent to opposite ends of said elongated head for engaging the rails and guiding said head for movement in a rectilinear direction towards said work surface;
• f. first and second rigid members extending laterally from opposite peripheral end portions of said torque tube towards said elongated heads;
• and,
• g. first and second lost motion coupling means coupling the extending ends of said first and second rigid members to said elongated head for supporting said head for arcuate movement upon rotation of said torque tube from a first position in which the rail engaging means are free of said rails to a second position in which said rail engaging means are in engagement with said rails, said lost motion coupling means including biasing means urging said head away from the axis of said torque tube so that said rail engaging means are urged into continuous positive engagement with said rails as said torque tube is further rotated beyond said second position towards a third position, said drills being moved rectilinearly into said material as said head is guided along the rails during the arcuate movement from the second to third position, said coupling means assuring that opposite end portions of said head move along said rails through precisely equal distances.