Apparatus for discharging drilling debris, drilling dust and the like, more particularly during the drilling operation in the case of hand drilling machine

A device for use with a hand drilling apparatus having a drill bit for discharging the debris formed by drilling into an object, said device comprising:

• (a) an enclosed chamber means having upper wall means, lower wall means and side wall means therebetween, said upper, lower and side wall means defining said enclosed chamber means, said enclosed chamber means being free of physical contact with said drilling apparatus, thereby allowing said drill bit to move axially and laterally without moving said chamber means, said chamber means having a first aperture in the top wall means thereof and a second aperture in the bottom wall means thereof, said chamber means positioned with respect to said drilling apparatus such that the second aperture of said chamber means is located over a borehole made by said drilling apparatus in the surface of the object, said bottom wall means of said chamber means including a sealing portion surrounding said second aperture wherein said drill bit is movable axially and laterally within the first and second apertures of said chamber means;
• (b) vacuum means for reducing the pressure in said chamber means;
• and
• (c) duct means for connecting said vacuum means to said chamber means, wherein said area of said first aperture is such that the flow cross-section for the ambient air drawn in through said inlet aperture with respect to the flow cross-section of said duct means is such that a negative pressure is maintained in said chamber means such that said sealing portion of said bottom wall means is sealed against the surface of said object and is held against the surface of said object surrounding the borehole by the negative pressure in cooperation with said sealing means and whereby the debris formed by the drilling collects in said chamber means and is withdrawn therefrom by said vacuum means through said duct means.