IMPROVEMENTS IN DENTAL ENGINES to be as follows:-
Year: 1884

page_text: I, DAVID BROWN, 14 Mill Lane, Montrose, in the County of Forfar, Dentist,
do hereby declare the nature of my said Invention for "IMPROVEMENTS IN
DENTAL ENGINES to be as follows:-
"
This Invention of improvements in dental engines consists in actuating the
drilling or piercing tool by means of a spring or springs and a train of toothed
wheels, which may be wound at intervals, or just before using the apparatus and
the motion of which may be controlled or stopped by means of a brake, and in so
forming and connecting the drilling or piercing tool on the handle or holder that it
may be conveniently adjusted to any required angle either from the outside or from
the inside of the mouth.
The spring or springs and clockwork are conveniently located on a table-like
framing which can be moved from place to place, and the rotatory motion of one
of the spindles of the train of wheels is conveyed to the improved holding and
piercing device through the usual flexible sheathed cable. The piercing tool holder
consists of a tubular handle through which is passed a spindle attached at one end
to the flexible cable and at the other fitted with a toothed pinion which gears with
a pinion on a short spindle carrying the drilling tool. The tool spindle is carried
in a moveable piece jointed to the end of the holder so that it may swivel, through
an arc, from a position in line with the driving spindle to the angle required.
To ensure the gearing or meshing of the pinions at any inclination of the
drilling tool the teeth of the pinions are made to project both radially and in a
lateral direction, so that the pinions may gear like crown wheels. The drilling or
piercing tool may be set and held at any degree of inclination by means of a screw
nut fitted to turn on the tool holder and engaging a notch in a link jointed to
the piece which holds the tool. The notched end of the link slides in a groove
sunk in the screwed end of the holder. When the screw nut is turned the link
cither draws the tool to an inclined position or pushes it into line with the holder,
according as the nut is turned in one direction or the other.

page_text: I, DAVID BROWN, 14, Mill Lane, Montrose, in the County of Forfar, Dentist,
do hereby declare the nature of my invention for IMPROVEMENTS IN DENTAL
ENGINES and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
This invention for improvements in dental engines, consists in actuating the
drilling or piercing tool by means of a spring or springs and a train of toothed
wheels, which may be wound at intervals, or just before using the apparatus and
the motion of which may be controlled or stopped by means of a brake, and in so
forming and connecting the drilling or piercing tool on the handle or holder that it
may be conveniently adjusted to any required angle either from the outside or from
the inside of the mouth. The spring or springs and clockwork are conveniently
located on or in a table-like framing which can be moveable or fitted to a moveable
bracket, and the rotatory motion of one of the spindles of the train of wheels is
conveyed to the improved holding and piercing device through a spindle or the
usual flexible sheathed cable. The piercing tool holder consists of a tubular handle
through which is passed a spindle attached at one end to the spindle or flexible
cable and at the other fitted with a toothed pinion which gears with the pinion on
a short spindle carrying the drilling tool. The tool spindle is carried in a move-
able piece jointed to the end of the tool holder, so that it may swivel through an
arc, from a position in line with the driving spindle to the angle required. To
insure the gearing or meshing of the pinions at any inclination of the drilling tool,
the teeth of the pinions are made to project both radially and in a lateral direction,
so that the pinions may gear like crown wheels. If desirable, any tool holder can
be attached to this arrangement. The drilling or piercing tool may be set and held
at any degree of inclination by means of a screw-nut fitted to screw on the tool
holder and engaging a notch in a link jointed to the piece which holds the tool;
the notched end of the link slides in a groove sunk in the screwed portion of the
holder; when the screw-nut is turned, the link either draws the tool to an inclined
position, or pushes it into line with the holder, according to the direction in which
the nut is turned. By means of a lever attached to the tool holder, the rotatory
motion can be stopped or started, the lever acting upon a pin or catch in the
driving spindle. A certain portion of the driving spindle is fitted into a tube, with
a pin and groove or slot, which allows of the length being varied by telescopic
action. The driving spindle is also fitted with the aforesaid joint and pinion
arrangement at its connection with the motive power.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1st The said arrangement of pinions or cog wheels with lateral and radial teeth,
enabling the transmission of rotary motion of shafts or spindles through a knuckle
joint whilst the said joint is either straight, at fixed angles or in motion, whether
applied to a dental engine or any other machinery or purpose whatsoever.

page_text: 2nd The adaptation to dental engines of the method described of controlling the
rotary motion of the tool spindle or instrument by a lever or other mechanical
attachment affixed to the tool spindle holder, (commonly known as the "hand
piece,") thus giving the operator instantaneous power to stop the instrument
without removing his hand from the "hand piece," or the "hand piece" from its
then position.
3rd The adaptation of the method described of the sliding rod for elongating or
shortening the driving spindle, thus enabling the operator to use the "hand piece "
at varying distances from the engine or motive power.
4th The adaptation of clockwork as a motive power, (enclosed in an ordinary
dental instrument table,) and the adaptation of the method of winding up the
clockwork spring by merely rotating the table top on its stem as an axis.
Dated this 20th dox of Santambar 1905
DAVID BROWN.