DENTAL HANDPIECE WITH DISPOSABLE DRILL HEAD ASSEMBLY

摘要

The dental handpiece (11) includes a disposable head assembly (15) and a reusable handle (13) which are removably coupled together. The head assembly (15) includes a housing (73) formed of plastic material forming a cavity (75) in which is located a turbine operated drill assembly (17) with a drill burr (101) extending out of a lower opening. The upper wall (73T) of the housing (73) is formed against the top of the drill assembly (17) to permanently fix the drill assembly in the cavity (75) such that the bearing mechanism for rotatably supporting the turbine (81) and drill burr (101) is integral with the head assembly (15). The head assembly (15) also has a neck with a cavity (107) for removably receiving the proboscis (45) of the handle (13) by way of a rear opening. The handle (13) supplies and removes air to and from the head cavity (75) for operating the turbine (81) and also supplies air, water and light from the proboscis (45) which are directed toward the burr (101) by way of an outlet opening (113). The handle (13) is snap-locked to the head assembly (15) when the proboscis (45) is located in the neck cavity (107). A protuberance (231) extends from the proboscis (45) for snap-locking the handle (13) and the head assembly (15) together. The lock mechanism (401) of the head assembly (15) may be broken away to remove the head assembly (15) from the handle (13) after which the head can be discarded. ~