Patent ID: 8172572
Filing Date: 2012-05-08
Classification: A61C

Abstract:
1. A dental tool displacement apparatus for use with a motorized power handle having a drive pin eccentrically mounted on an output drive shaft to displace a dental tool, the displacement apparatus comprising: (a) a tool holder having a receptacle for receiving the dental tool, said receptacle defining a tool axis; (b) a drive arrangement associated with said tool holder and the motorized power handle, said drive arrangement defining a transmission from the motorized power handle to said tool holder such that said tool holder undergoes reciprocating motion parallel to said tool axis at a first frequency of oscillations per minute and rotates about said tool axis at a second frequency of rotations per minute, wherein said first frequency is at least one order of magnitude greater than said second frequency, and wherein said drive arrangement comprises an annular slot circumscribing said tool axis, said annular slot being formed between a first and a second opposing surfaces, said annular slot receiving the eccentrically mounted drive pin so that motion of the drive pin within said annular slot generates said reciprocating motion of said tool holder, and wherein said first opposing surface is provided with a sequence of axially projecting gear teeth arrayed around said axis such that, during a revolution of the output shaft, the drive pin engages said gear teeth, generates a rotational step of said first opposing surface and disengages from said gear teeth.