Year: 1888

page_text: I, DAVID RALPH EDEN of Breakfast Creek Road, Brisbane in the Colony of
Queensland, Surgeon Dentist do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascertained
in and by the following statement :—
My invention relates to apparatus that can be held in the hand of a dentist and
is so arranged that rotary motion being communicated to a central spindle within
the handle longitudinal reciprocation is given to a file which, projecting from the
front end of the handle, can be applied to file the teeth of a patient. I will describe
apparatus according to my invention referring to the accompanying drawings which
are drawn to an enlarged scale, about six times the real size, in order more clearly
to shew the construction and arrangement of the parts.
Figs. 1 and 2 are elevations on planes at right angles to each other shewing the
front part of the handle with the gearing in position.
Figs. 3 and 4 are similar views of the file holder shewn detached. Figs. 5 and 6
are sectional plans thereof at X and Y respectively.
Fig. 7 is an elevation partly in longitudinal section and
Fig. 8 is a transverse section at Z of the revolving spindle.
Fig. 9 is a side view of a modification.
The central spindle A is, towards its front end, made tubular to form a sleeve Cat
the end of which is a bevil or mitre pinion B.
The file holder is for part of its length F tubular and square in section and for
part G it is round terminating in a round collar H which is fitted to work within
the sleeve C. In the square part F there is near one end a cross slot K. and
near the other end there is a spring catch D to hold in the stem of the file L
which is inserted in F. The handle M, part of which is shewn in Figs. 1 and 2 has
formed within it bearings for the rotating spindle A and has attached to it a framing E E
which has in its front a square hole to receive the square part F of the file holder,

page_text: and at its side a hole for the short spindle N of a bevil or mitre pinion O that gears
with B.
From the face of this pinion O a crank pin P projects into the slot K of the file
holder F. Rotation being communicated through a flexible shaft from a foot latho or
other suitable motor to the spindle A causing the mitre gearing B and O to revolve,
the crank pin P working in the slot K causes the file holder F and the file L carried
by it to reciprocate, while the fitting of F into the square guide at the front end of
the handle prevents the tool holder from turning.
Instead of arranging the tool holder to reciprocate as described within the driving
spindle it may be mounted outside the handle frame as shewn by the side views
Fig. 9.
In this case the crank pin P projects from the face of the collar of the short
spindle N and the file holder F works through guides Q and R fixed on the frame,
the guide being square to prevent the holder from turning.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
An apparatus for filing teeth consisting of a handle within which is mounted a
revolving spindle that drives by bevil or mitre gear a crank pin working in a trans-
verse slot of a file holder fitted to reciprocate in guides in or on the handle, substan-
tially as described.
Dated this 6th day of January 1888.
ABEL & IMRAY,
Agents for the Applicant.