초록 ▼

A cranial perforator with an internal clutch which is engaged when the drill is placed against a bone surface for drilling and which will automatically release when the drill penetrates the skull. The components of the drill are held together by a plastic sleeve and a retaining ring which is ultraso

A cranial perforator with an internal clutch which is engaged when the drill is placed against a bone surface for drilling and which will automatically release when the drill penetrates the skull. The components of the drill are held together by a plastic sleeve and a retaining ring which is ultrasonically welded to the interior surface of the plastic sleeve.

대표청구항 ▼

In an apparatus for drilling bone structure comprising: a generally cylindrical primary drill member having a distal end and having a proximal end; a generally cylindrical driver having a distal end disposed in confronting relationship to said primary drill member and having a proximal end; clutch m

In an apparatus for drilling bone structure comprising: a generally cylindrical primary drill member having a distal end and having a proximal end; a generally cylindrical driver having a distal end disposed in confronting relationship to said primary drill member and having a proximal end; clutch means cooperatively disposed between said primary drill member and said driver whereby when said clutch means is engaged, said drill member and said driver rotate as a unit and drill into the bone structure, and when said clutch is disengaged, said primary drill member remains stationary as said driver rotates; an annular drill body slideably and rotatably receiving said primary drill member and said driver, said annular drill member including a recess extending around the exterior surface of said annular drill body; an annular sleeve disposed about said drill body having a proximal end operatively engaging said driver; the improvement comprising: discrete, arcuate retaining ring means having a medial portion and two edge portions disposed in said annular drill body recess and having means to be rigidly affixed to said sleeve for holding said driver and said annular drill body together against forces exerted in the axial direction; said retaining ring means when so bonded being freely rotatable in said annular drill body recess so as not to inhibit the rotational motion of said sleeve with respect to said annular drill body; and wherein the outer circumferential surface of said retaining ring means before being so bonded confronts the interior surface of said sleeve and includes an energy directing means including an outwardly extending generally triangular taper on its outer periphery with the medial portion of said retaining ring means being thicker than the two edge portions.