Aspirating dental drill

Claim 1

A DENTAL DRILL COMPRISING: AN ELONGATED HOLLOW SHEATH ADAPTED TO BE CONNECTED AT ONE END WITH A VACUUM HOSE, SAID SHEATH HAVING AT THE OTHER END A CIRCULAR OPENING AND ADJACENT SAID OPENING A HOLLOW CYLINDRICAL PORTION DEFINED BY INWARDLY EXTENDING CYLINDRICAL INTERIOR WALLS; A HOLLOW ELONGATED KNEE HAVING AT ONE END RIGHT CIRCULAR CYLINDRICAL WALLS ADAPTED TO FIT SNUGLY THROUGHT SAID CIRCULAR OPENING AT SAID OTHER END OF SAID SHEATH AND TO ENGAGE IN FACE TO FACE RELATION WITH SAID CYLINDRICAL INTERIOR WALLS OF SAID SHEATH; A COLLAR SLIDABLY MOUNTED ON SAID KNEE AND ADAPTED TO MOVE SELECTIVELY BETWEEN A FIRST POSITION WHEREIN AN APERTURE IN SAID KNEE IS FULLY COVERED BY SAID COLLAR AND A SECOND POSITION WHEREIN SAID APERTURE IS FULLY EXPOSED; A HOLLOW DRILLING HEAD MOUNTED ON THE OTHER END OF SAID KNEE; MEANS ON SAID DRILLING HEAD FOR DIRECTING THE MOVEMENT OF AIR INDUCED BY A VACUUM IN SAID HOSE FROM THE ATMOSPHERE OUTSIDE SAID DRILLING HEAD TO A LOCATION WITHIN SAID DRILLING HEAD; AND A DRILL-HOLDING CHUCK ROTATABLY MOUNTED WITHIN SAID DRILLING HEAD, SAID CHUCK INCLUDING AIR-FLOW RESPONSIVE MEANS FOR ROTATING SAID CHUCK, SAID AIR-FLOW-RESPONSIVE MEANS BEING LOCATED WITHIN THE PATH OF AIR MOVEMENT DETERMINED BY SAID AIRDIRECTING MEANS.