Improvements in Dental Boring Machines.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Dental Boring Machines.
I, LEOPOLD GERECHTER of 43 Rosenthaler Strasse, Berlin, in the Kingdom of
Prussia, Empire of Germany, Mechanic 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 :-
My invention relates to a dental boring machine in which the hand-piece may be
moved about easily and used in any position desired.
I attain this effect by employing a driving gear in which the fly-wheel of the
machine rotates a small wheel of an elastic material, such as india-rubber or leather,
said wheel being in contact with the lateral surface of the fly-wheel, which is made
plane at that place.
In order that my invention may be fully understood, I will proceed to describe
the form in which I prefer to construct my improved machine, referring to the
accompanying drawings, in which:
Fig. 1 is a front elevation of my improved machine,
Fig. 2 is a side elevation of the same,
Fig. 3 is a detail view, partly in section, showing the hinged head of the machine
and part of the driving gear.
B
Fig. 4 is a rear elevation of the lower portion of the machine.
Similar letters denote similar parts throughout the several views.
In carrying out my invention, I construct the machine of a standard A kept in
an upright position by feet B and carrying a fork C in which are provided the
bearings for a short shaft D. The fly-wheel E is secured to this shaft between the
arms of the fork C, and another fork F is loosely mounted on the same shaft so
that it may be inclined at various angles (see Fig. 4). One arm of the fork F
extends downwards beyond the shaft D, and is provided with an eye or short
sleeve G, through which passes a flat spring H, secured to a bracket projecting
from the standard A; said spring may be guided on rollers within the sleeve G in
order to reduce friction (this construction is not shown in the drawings, but is of
current use, and does not form a part of my invention). The shaft D is provided
with a crank 1, linked to a treadle J by means of an elastic connecting-rod K. The
fork F is formed with a ring L serving as a handle by which the whole machine
may be lifted and carried. To the upper end of fork F is secured a tube M,
upright in its normal position; within this tube is enclosed a shaft N carrying at its
lower end a small wheel O the rim of which consists of india-rubber, leather or a
similar yielding material. The lateral surface of the fly-wheel E, on which the
wheel bears, is made plane in order to ensure a good and uniform contact.
tube M is provided with a collar P at its upper end; a sleeve Q, enclosing the upper
end of tube M rests on this collar and may be turned as desired. To this sleeve Q
is secured the head R, to which a bracket S is hinged. This bracket carries a
tube T, in which is enclosed a sleeve U. A spiral spring V is secured with one end
to the upper extremity of shaft N and with the other end to the sleeve U. The
latter may freely revolve within the tube T, and receives a rod W provided with a
longitudinal groove W. A stud or projection X on the sleeve U enters the
groove Wand causes the spiral spring VI to rotate when the spiral spring V begins
to turn. The spiral spring V₁ is enclosed in a suitable flexible tube Y, and is
adapted to rotate the bit of the hand-piece Z secured to the end of this tube.
spring H prevents the spiral spring V₁ from being bent too abruptly near the
The fly-
The operation of my improved machine will be readily understood.
wheel E being rotated by means of the treadle J, connecting-rod K and crank I,
head R.
The
A

page_text: will cause the small wheel O to partake of its rotation, so that the spiral spring V
and the sleeve U connected to the same will follow this movement, and the stud X
will cause the rod W and the spiral spring connected to the same to be rotated,.
so that this motion will be transmitted to the bit of the hand-piece Z. The flexibility
of the tube Y permits the hand-piece to be held at any angle, and as the bracket Š
may be turned around the hinge connecting it to the head R, the movement of the
tube Y is greatly facilitated. As will be seen at Fig. 2, the upper end of tube Y
may even be held absolutely vertical. The adjustability of the hand-piece is still
increased by the possibility of turning the tube M and fork F around the shaft D,
as indicated by dotted lines in Fig. 4. The spring H will keep the fork F in any
position and prevent any spontaneous movement of the same.
The employment of the longitudinally grooved rod W is very advantageous, as
thereby any fongitudinal tension of the spiral spring V is avoided when turning the
tube Y downwards into the position illustrated by Fig. 2. It will be obvious that
a good transmission of the rotation by the spiral spring V is ensured by this means.
I do not confine myself to the exact form of construction described and shown in
the drawings, and I wish more particularly to point out that instead of the fork F,
I may employ a single arm for carrying the tube M and wheel O.
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 -
:-
1. A dental boring machine in which the motion of the fly-wheel, which is rotated
by means of a treadle, connecting-rod and crank, is transmitted by friction to a small
wheel of india-rubber, leather or a similar. material located laterally of the fly-wheel,
said small wheel being secured to an upright shaft enclosed within a tube connected
to the frame of the machine, for the purpose of obtaining a free mobility of the
hand-piece.
2. In a dental boring machine of the kind claimed under head 1: The fork For
an arm or holder replacing the same, said fork or holder being provided, laterally
of the fly-wheel E, with suitable hollow parts for receiving an upright shaft provided
with a small wheel O of india-rubber leather, or a similar material, whereby the
motion may be transmitted from the fly-wheel E to the upper part of the machine,
substantially as described, for the purpose set forth.
3. In a dental boring machine of the kind claimed under head 1: The hinge-joint
provided at the upper end of the upright tube M, and formed of the head R,
secured laterally to a sleeve Q which may be turned on the tube M, and of the
bracket S, hinged to the head R, substantially as described, for the purpose set
forth.
4. In a dental boring machine of the kind claimed under head 1: As a means for
transmitting motion from the vertical shaft to the hand piece L, a spiral spring
consisting of two pieces V VI, the former being secured to a sleeve U having a
projection or stud X, and the latter to a rod W having a longitudinal groove W
adapted to receive the stud X, substantially as described, and for the purpose of
avoiding a longitudinal tension of the spiral spring when turning the bracket S
hinged to the head R into a vertical position.
Dated this 20th day of October 1892.
LEOPOLD GERECHTER,
By Geo. H. Rayner,
37, Chancery Lane, London, W.C., Agent for the Applicant.