Improvements in and relating to Dental Engines and Appliances.
Year: 1894

page_text: Date of Application, 9th Jan., 1894
Complete Specification Left, 9th Oct., 1894-Accepted, 10th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in and relating to Dental Engines and Appliances.
I, WILLIAM WALLACE, of 36 Dundas Street, in the City and County of
Glasgow, Bachelor of Medicine and Dental Surgeon, do hereby declare the nature
of my invention to be as follows:-
This invention has reference to and comprises a new and improved method of
arranging and combining appliances and mechanisms in dental engines driven by
electricity whereby the patient can be operated on in a more simple and efficient
way and with greater convenience to the dentist.
The improvements essentially consist in taking that portion of the engine made
up chiefly of the electro-motor and suspending same by loose or movable jointing,
so that it being the heavier may counterbalance or counterpoise the lighter portion
which is preferably made up of a rod rigidly and adjustably fixed to the motor, a
movable arm and a hand piece for the dental bits, these being driven by an endless
connecting driving cord running from the rotating spindle of the electro-motor to
the hand piece and guided by pulleys situated near or at the joints connecting
the rods.
In carrying these improvements into practice I would support and suspend the
electrical dental motor from a bracket or movable stand by means of loose or
movable jointing at a point which would form a centre of oscillation for the lighter
and heavier portions of the engine so that the heavier portion by its greater weight
would hang down and the lighter portion stand up above it. The stable
equilibrium thus effected would nevertheless be easily disturbed by the leverage
afforded by the length of the upstanding rod when the operator moves the apparatus
on its centre of oscillation, and thus facilitate his operation and further when he
ceased to act on the upstanding rod the apparatus would oscillate back into and
resume a convenient position of rest in stable equilibrium.
I would or may construct the loose or movable jointing connecting the electrical
dental engine and the bracket or stand in a variety of equivalent ways such as the
following:
(1.) A universal or ball and socket joint ;-the stem of the socket being fixed in
the bracket or stand and the stem of the ball being fixed to the engine or
vice versa.
(2.) Two or more links, rings or hooks ;-the uppermost being fixed in the
support and the lowest in the engine.
(3.) A cross-pin fitted into side cheeks with eye bearings;-the ends of one
limb of the cross-pin fitting into eye bearings in side cheeks rising vertically from
the dental engine and the ends of the other limb of the cross-pin fitting eye
bearings in side cheeks at right angles to the other coming vertically downwards
from the support.
(4.) A pivoted ring fitting into eye bearings in side cheeks fixed to the support
with a spindle fixed to a stud pin and attached to the engine turning in eye
Or
bearings in said ring at right angles to the other eye bearings or vice versa.
instead of the spindle an inner ring may be used with journals working in bearings
in the outer ring, and have the motor connected to this inner ring.

page_text: (5.) A single spindle fixed by a stud to the engine and moving in eye hearings
in the stand or vice versa but by this arrangement the engine would only oscillate in
one plane.
Dated the 8th January 1894
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.
COMPLETE SPECIFICATION.
Improvements in and relating to Dental Engines and Appliances.
I, WILLIAM WALLACE, of 36 Dundas Street, in the City and County of
Glasgow, Bachelor of Medicine and Dental Surgeon, do hereby declare the
nature of my invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement in writing
that is to say :-
This invention has reference to and comprises a new and improved method of
arranging and combining appliances and mechanisms in dental engines driven by
electricity whereby the patient can be operated on in a more simple and efficient
way and with greater convenience to the dentist.
And in order that my said invention and the mauner of performing or carrying
the same into effect or practice may be properly understood I have hereunto
appended an explanatory sheet of drawings, in which the same reference letters are
used to indicate corresponding parts in all the figures where shown.
Figure 1 is an elevation of a dental engine as fitted in accordance with one
arrangement of my improvements.
Figures 2 and 3 are a detached elevation and corresponding plan view to au
enlarged scale of the loose or movable jointing mechanism between the dental
engine and stand shown in Figure 1. While
Figures 4 to 9 represent views of modified forms of corresponding swivelling joints
hereinafter referred to.
Referring to these drawings
My improvements essentially consist in taking that portion of the engine made
up chiefly of the electro motor A and suspending same by loose or movable jointing,
so that it being the heavier may counterbalance or counterpoise the lighter portion,
which is preferably made up of a rod B rigidly and adjustably fixed to the motor A,
a movable arm C and hand piece D for the dental bits these being driven by an
endless connecting driving cord E running from the rotating spindle A' of the
electro-motor A to the hand piece D and guided by pulleys E' situated near or at
the joints connecting the rods.
In carrying these improvements into practice I would support and suspend the
electrical dental motor A from a bracket F on a movable stand F by means of
loose or movable jointing at a point which would form a centre of oscillation for the
lighter and heavier portions of the engine so that the heavier portion A by its
greater weight would hang down and the lighter portion B stand up above it. The
stable equilibrium thus effected would nevertheless be casily disturbed by the
leverage afforded by the length of the upstanding rod B when the operator moves
the apparatus on its centre of oscillation and thus facilitate his operation and
further when he ceased to act on the upstanding rod the apparatus would oscillate
back into and resume a convenient position of rest in stable equilibrium. I would
or may construct the loose or movable jointing connecting the electrical dental
engine A and the bracket and stand F, F, in a variety of equivalent ways such as
the following:-
(1.) A universal or ball and socket joiut as shown in detached sectional
elevation in Figure 4. The stem a' of the socket a being fixed in the bracket F

page_text: and the stem b¹ of the ball b being fixed at A' to a vulcanite plate on the engine A
or vice corsa.
(2.) Two or more hooks, rings, or links, as shown in detached elevation broken
away in Figure 5 the uppermost hook a being fixed in the support F and the lowest
ring or link to an eye in the engine A. the lower end of the rod B being in this
case shown as formed of a kneed shape.
(3.) A cross pin fitted into side cheeks with eye bearings as shown detached in
elevation Figure 6 and horizontal section in Figure 7 the latter being taken on the
line 7-7 Figure 6. In this arrangement the ends of the limbs 6 of the cross pin
fit into eye bearings at 6', 6', in side cheeks 6 6 rising vertically from the vulcanite
plate A2 on the dental engine A and the ends a¹, a¹ of the other limbs a of the cross
pin fit eye bearings in side cheeks a² at right angles to the other coming vertically
downward from the support F.
(4.) As shown in Figures 1 to 3 a pivot ring or link a with the pivots a¹ fitting
into eye bearings in side cheeks F' forming part of or fixed to the support F and
secured by washers and cotters at f; and having a spindle 6 passing through the
rod B of engine A and sides of the link a at 63 at right angles to the eye bearing
at a or vice versa. Or as shown in detached plan view Figure instead of the
spindle, an inner ring 6 may be used with journals working in bearings in the
outer ring a and have the motor connected to this inner ring b, while the outer
ring a would have its pivots a' working in eye bearings in the side cheeks F2 of the
support F.
(5.) As shown in detached elevation Figure 9 a single spindle a is fixed by a
stud to the rod B of engine A and moves in eye bearings at a' in the cheeks F of
stand F, or vice versa, but by this arrangement the engine A would only oscillate in
one plane.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what
claim is
First. In dental engines the method of suspending the electro motor by means of
loose or movable jointing, so that it shall counterbalance or counterpoise the lighter
portion of the mechanism or appliances substantially as herein set forth.
Second. In dental engines the combination with the engine and the bracket or
stand of loose or movable jointing substantially as and for the purposes herein
described in reference to and by way of application shown in the accompanying
drawings.
Dated the 8th October 1894.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.