In line rotary driling machine for producing uniform openings in

Abstract

A rotary drilling machine for forming holes of selected size and spacing in continuous strip material such as elastomeric gasket stock used for the manufacture of gaskets for door openings and the like. This machine has a rotary drum unit which carries the strip material along a portion of its peripheral edges. A plurality of drilling units are mounted on this drum unit so as to move with the strip material. The drilling units are oriented toward the peripheral edge, and these drilling units are moved radially in a proper sequence whereby drill bits thereof move toward the strip material to dril the holes and then retract. Tensioning elements produce friction between the strip material and the periphery of the drum unit to accomplish the movement thereof in unison. The tensioning elements, in a preferred form, have signal generating elements whereby the speed of rotation of the drum unit is controlled to prevent sag in the run of the strip material. The radial movement of the drilling units is preferably controlled with a cam and cam follower arrangement. Air for driving driling motors and water for cooling the drill bits is fed to the machine through passageways in the drive shaft for the drum unit. The construction of this machine provides for very accurate drilling of the holes, and a high rate of production with very little maintenance.