Angle handpiece

In a hand piece assembly for a surgical instrument, the improvement comprising:

• angled housing means including an elongated tubular grip portion having one end thereof fixedly connected to an elongated tubular nose portion, the longitudinal direction of said nose portion extending at an angle relative to the longitudinal directionof said grip portion;
• a first removable cartridge unit positioned within said grip portion, said first cartridge unit having motor means disposed therein;
• a second removable cartridge unit disposed within said grip portion and positioned axially in series with said first cartridge unit, said second cartridge unit having speed reducer means disposed therein;
• first disconnectible coupling means for permitting the transmission of driving torque from said motor means to said speed reducer means;
• removable means fixedly associated with the other end of said tubular portion for holding said cartridges within said grip portion;
• a rotatable drive shaft coaxial with and rotatably supported within said tubular nose portion, and gear means disposed substantially at the intersection between said grip and nose portions for drivingly connecting said drive shaft to the output of said speed reducer means;
• means associated with said nose portion adjacent the free end thereof for permitting a rotatable tool to be drivingly connected to said drive shaft, said last-mentioned means including a narrow slot formed within and extending diametrically of said drive shaft and opening outwardly through the free end thereof;
• and
• a unitized tool assembly for releasable attachment to said nose portion, said tool assembly including an elongated support sleeve having a rearward end thereof insertible into the free end of said nose portion, and first and second cooperating coupling means respectively formed on said nose portion and the rearward end of said support sleeve for fixedly but releasably connecting said support sleeve to said nose portion;
• said tool assembly also including an elongated tool coaxially aligned with and rotatably supported within said support sleeve, said tool being axially fixedly mounted on said support sleeve and having a driving portion in the form of a flat tongue projecting axially from the rearward end thereof, said tongue being slidably insertible into the slot formed in said drive shaft for nonrotatably coupling said tool to said drive shaft, said tool having a shaft portion projecting outwardly from the forward end of said support sleeve and terminating in a cutting element, said support shaft adjacent the forward end of said support sleeve having a conical enlargement which enlarges smoothly to an outer diameter which is substantially equal to the outer diameter of the adjacent end of said support sleeve, said conical enlargement terminating in a shoulder which is disposed adjacent and substantially abuts the forward end of said support sleeve.