Dental handpiece assembly

An adaptor for connecting to a dental handpiece to provide sterile fluid solution to the handpiece discharge under pressure from a propellant gas, said dental handpiece of the type having a tubular body, a neck connected to the downstream end of the body, and a head connected to the neck, means in the head for connection of a rotary working tool, a drive air conduit, a return air conduit, a chip air conduit and a liquid conduit all extending from the upstream inlet end of the body to the downstream discharge end, said adaptor comprising:

• a tubular insert member having an upstream end and a downstream end, a drive air line extended the length of the tubular insert member adapted for connection to a compressed gas supply at the upstream end thereof, a return air line extending the length of the tubular insert member, a chip air line open at the downstream end of the tubular member and terminating at an interior location therein, and a liquid line open at the downstream end of the insert member and terminating at an interior location thereon;
• said drive air line, return air line, chip air line and liquid line having receptacles at the downstream end of the insert member for receipt of the drive air conduit, return air conduit, chip air conduit and liquid conduit of the dental handpiece in plug type relationship;
• a connector for connection to the tubular insert member of a disposable fluid cartridge of the type comprised as a housing having an inlet chamber and an outlet chamber and including movable pressure communicating means separating the inlet chamber and the outlet chamber in fluid type relationship and movable with respect to the housing to vary the volumes of the chambers in reciprocal fashion, inlet means to the inlet chamber of the cartridge, outlet means to the outlet chamber of the cartridge, said outlet chamber being initially filled with a sterile liquid and occupying virtually the entire volume of the cartridge with said inlet chamber volume reduced to virtually zero;
• said insert member having a first port intersecting the drive air conduit, a first fluid passage connecting to the first port;
• a second fluid passage connected to the liquid delivery line;
• arm means having an inlet channel connected to the first fluid passage and connectable to the inlet means of the fluid cartridge so that some compressed gas from the drive air line is diverted to the inlet chamber of the cartridge to function as a propellant to move the liquid out of the outlet chamber;
• said arm means having an outlet channel connected to the second fluid passage of the insert member and connectable to the outlet means of the fluid cartridge to allow liquid to flow from the outlet side of the cartridge to the fluid line of the insert member upon introduction of gas under pressure to the inlet side of the cartridge;
• and
• means for removable connection of the fluid cartridge to the arm means.

A dental handpiece assembly comprising:

• a tubular housing having a downstream end and an upstream end;
• a head assembly at the downstream end, having a reciprocating compressed gas driven motor for connection to a working tool to perform a dental procedure upon a patient;
• said tubular housing carrying a drive air conduit, return air conduit, and a liquid conduit;
• said drive air conduit extending from the downstream end of the housing to the head assembly to provide pressurized gas to drive the rotary motor in the head assembly, the end of the drive air conduit at the upstream end of the housing having means for connection to a supply of gas under pressure;
• said liquid conduit having a downstream discharge end at said head assembly, and an upstream terminal end;
• a disposable liquid cartridge comprised as a second housing having a movable flexible diaphram dividing the interior of the housing into an inlet chamber and an outlet chamber and movable with respect to the housing interior to vary the volumes of the chambers in reciprocal fashion, and inlet means to the inlet chamber, and an outlet means to the outlet chamber;
• first fluid passage means intersecting the drive air conduit of the tubular housing to divert a portion of compressed gas from it, and means for releasable connection of the first fluid passage means to the inlet means of the inlet chamber of the liquid cartridge;
• second fluid passage means connected at the terminal upstream end of the fluid line and releasably connectable to the outlet means of the liquid cartridge to provide passage of liquid from the outlet chamber of a liquid cartridge of the fluid line upon introduction of compressed gas to the inlet chamber of the cartridge.