Double insulated drill bit sharpener

Claim 2

A drill sharpener including a casing, an electric motor supported within said casing and having an output rotary shaft, a sharpener head fixed to said casing, said head having a spindle rotatably supported thereon, an abrasive sharpening wheel fixed to said spindle, a torque transmitting coupling having one end thereof formed of hollow, cup-shaped configuration and loosely and non-rotatably receiving one end of said spindle, said coupling having its other end threaded into said shaft, whereby to electrically insulate said shaft from said spindle and accommodate small tolerance variations and misalignment therebetween.

Claim 3

A drill bit sharpener comprising a motor housing having an electric motor therein, an electrically insulating casing including first and second telescoped members enclosing said motor housing, a baffle fixed within one of said casing members and supporting said motor, said baffle being constructed of electrically insulating material and cooperating with said one casing member whereby to retain electric conductor means in place within said one casing member, a sharpener head including a body fixed to said casing and having a spindle rotatably supported thereon, an abrasive wheel fixed to said spindle, said motor having a rotatable output shaft, and insulating means coupling said motor shaft to said spindle.

Claim 4

A drill bit sharpener comprising a motor housing having an electric motor therein, an electrically insulating casing including first and second telescoped members enclosing said motor housing, a baffle fixed within one of said casing members and supporting said motor, said baffle being constructed of electrically insulating material and cooperating with said one casing member whereby to retain electric conductor means in place within said one casing member, a sharpener head including a body fixed to said casing and having a spindle rotatably supported thereon, an abrasive wheel fixed to said spindle, said motor having a rotatable output shaft, and insulating means coupling said motor shaft to said spindle.

Claim 5

A drill sharpener comprising an electrically insulating casing, an electric motor supported within said casing and having an output shaft, a sharpener head fixedly supported upon said casing, an abrasive wheel encased within and rotatably supported upon said head and coupled to said shaft, said abrasive wheel having a conical end face defining a sharpening surface, said head having means thereon to guide and support selected sized drill bits with their cutting lips in stationary sharpening engagement with said sharpening surface.

Claim 6

A drill sharpener comprising an electrically insulating casing, an electric motor supported within said casing and having an output shaft, a sharpener head fixedly supported upon said casing, an abrasive wheel encased within and rotatably supported upon said head and coupled to said shaft, said abrasive wheel having a conical end face defining a sharpening surface, said head having means thereon to guide and support selected sized drill bits with their cutting lips in stationary sharpening engagement with said sharpening surface.

Claim 7

A drill bit sharpener ad defined in claim 3 which includes means electrically insulating said motor from said sharpening head.

Claim 8

A drill sharpener as defined in claim 4 wherein said insulating means includes an insulating coupling interconnecting said shaft and a spindle to which said abrasive wheel is fixed.

Claim 9

A drill sharpener as defined in claim 3 wherein said casing includes a pair of telescopic members axially trapping said motor therebetween.

Claim 10

A drill sharpener as defined in claim 6 which includes a baffle fixed to one of said members and laterally supporting said motor.

Claim 11

A drill sharpener as defined in claim 3, wherein said casing includes separable, electrically insulating members enclosing said motor, a line cord extending from said casing for connecting said motor to an electric source, electrical switch means on said casing, electrical conductors within said casing and connecting said motor, said switch, and said line cord, said casing members defining a wireway confining said conductors.

Claim 12

A drill sharpener comprising an electric motor enclosed in a housing, said motor having transmission means within said housing and an output shaft accessible from outside said housing, an electrically insulating casing substantially completely enclosing and trapping said housing therein, a sharpener head fixedly supported upon said casing, an abrasive wheel rotatably supported within and upon said head and having a conical end face defining a sharpening rotatable about an axis substantially aligned with the axis of said output shaft, means coupling said ouTput shaft and said abrasive wheel for conjoint rotation, said head including means locating drill bits with their cutting lips in stationary sharpening engagement with said sharpening surface, electric switch means for said motor, said switch means being disposed within said casing and including an electrically insulating operator accessible from outside said casing.

Claim 13

A drill sharpener comprising an electric motor enclosed in a housing, said motor having transmission means within said housing and an output shaft accessible from outside said housing, an electrically insulating casing substantially completely enclosing and trapping said housing therein, a sharpener head fixedly supported upon said casing, an abrasive wheel rotatably supported within and upon said head and having a conical end face defining a sharpening rotatable about an axis substantially aligned with the axis of said output shaft, means coupling said ouTput shaft and said abrasive wheel for conjoint rotation, said head including means locating drill bits with their cutting lips in stationary sharpening engagement with said sharpening surface, electric switch means for said motor, said switch means being disposed within said casing and including an electrically insulating operator accessible from outside said casing.

Claim 14

A drill sharpener as defined in claim 1 wherein said coupling has a cylindrical projection in said cup-shaped end adapted to fit into said one end of said spindle, whereby to help align said spindle and said shaft.