US 5,334,013 A · High speed dental drill with positive pressure air drive

Abstract

A high speed dental drill includes a drill head having a housing including a bottom and a cavity, and a turbine assembly mounted in the cavity for supporting a dental tool extending outwardly from the bottom of the housing, the turbine assembly including a rotor shaft and an annular turbine drive mounted thereon. The outer surface of the annular turbine drive has blades with an outer shape of a substantially inverted D-shaped chordal segment cut out therefrom so that rotation of the rotor shaft occurs at high speed when air impinges against the part-circular cut-away surfaces of the blades. Bearing assemblies rotatably support the shaft of the turbine assembly, and an exhaust is provided for exhausting air from the turbine assembly out of the bottom of the housing and to create and maintain positive air pressure in the housing, even during turn off of the drill, so as to prevent liquid from being drawn up into the housing, the exhaust including an exhaust hole in the bottom of the housing and an exhaust channel formed in the housing for supplying air to the exhaust hole from the turbine assembly. An elongated handle is connected with the housing, and has an air conduit in communication with the cavity of the housing for supplying pressure air against the turbine assembly, and a water conduit for supplying water under pressure through a water spray hole in the housing so that a water spray impinges upon the drilling tool during use.

Claims40

Dependent claims

A high speed dental drill comprising:

a drill head including:
a housing including a bottom and a top, and a cavity therein;
turbine assembly means mounted in said cavity of said housing for supporting a dental tool extending outwardly from said housing;
support means for rotatably supporting said turbine assembly means in said cavity of said housing;
an elongated handle having a distal end connected with said housing, said elongated handle including air conduit means in open communication with said cavity of said housing for supplying driving air under pressure against said turbine assembly means so as to cause rotation of said turbine assembly means and rotation of said tool, the air being exhausted from said turbine assembly means after the air is passed through said turbine assembly means to cause said rotation;
and
exhaust means for exhausting substantially all of said exhaust air from said turbine assembly means out of said bottom of said housing so as to create and maintain a positive air pressure in said housing at all times, even during turn off of the drill, so as to prevent liquid from a patient's mouth from being drawn by suction into said cavity of said housing.

4 more elements

A high speed dental drill comprising:

a drill head including:
a housing including a bottom and a top, and a cavity therein;
turbine assembly means mounted in said cavity of said housing for supporting a dental tool extending outwardly from said housing;
support means for rotatably supporting said turbine assembly means in said cavity of said housing;
an elongated handle having a distal end connected with said housing, said elongated handle including air conduit means in open communication with said cavity of said housing for supplying driving air under pressure against said turbine assembly means so as to cause rotation of said turbine assembly means and rotation of said tool, the air being exhausted from said turbine assembly means after the air is passed through said turbine assembly means to cause said rotation;
and
exhaust means for exhausting at least 60% of said exhaust air from said turbine assembly means out of said bottom of said housing and for exhausting the remainder of said exhaust air from said turbine assembly means out of said top of said housing, so as to create and maintain a positive air pressure in said housing at all times, even during turn off of the drill, so as to prevent liquid from a patient's mouth from being drawn by suction into said cavity of said housing.

4 more elements

A high speed dental drill comprising:

a drill head including:
a housing including a bottom and a top, and a cavity therein;
turbine assembly means mounted in said cavity of said housing for supporting a dental tool extending outwardly from said housing;
support means for rotatably supporting said turbine assembly means in said cavity of said housing;
an elongated handle having a distal end connected with said housing, said elongated handle including air conduit means in open communication with said cavity of said housing for supplying driving air under pressure against said turbine assembly means so as to cause rotation of said turbine assembly means and rotation of said tool;
and
exhaust means for exhausting air from said turbine assembly means out of said bottom of said housing so as to create and maintain a positive air pressure in said housing at all times, even during turn off of the drill, so as to prevent liquid from a patient's mouth from being drawn by suction into said cavity of said housing;
said exhaust means including an exhaust hole in said bottom of said housing, and exhaust channel means in said housing for supplying air exhausted from said turbine assembly means to said exhaust hole;
and
wherein said support means includes bearing means for rotatably supporting said turbine assembly means, and O-ring means for fixedly supporting said bearing means in said cavity of said housing, and wherein said exhaust channel means extends between said O-ring means and said distal end of said elongated handle.

7 more elements

Dependencies are inferred from the claim text.

High speed dental drill with positive pressure air drive

Life of this patent

High speed dental drill with positive pressure air drive

Life of this patent

Abstract

Claims40