Improvements in Cog Wheels.
Year: 1890

page_text: “Date of Application, 24th June, 1890-Accepted, 26th July, 1890
COMPLETE SPECIFICATION.
Improvements in Cog Wheels.
I, LEONARD ATWOOD, of 416 Walnut Street, in the City of Philadelphia, State of
Pennsylvania, U.S.A. Mechanical Engineer, do hereby declare the nature of the said
Invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
The object of my invention is to construct a sectional cog wheel provided with
detachable teeth in the manner hereinafter described, reference being had to the
accompanying drawings, in which:
11
Fig. 1, is a face view of my improved wheel.
Fig. 2, is a section on the line, 1-2, Fig. 1;
Fig. 3, is a face view partly in section, of the rim ;
Fig. 4, is a view of the centre;
Fig. 5, is an enlarged view showing the application of the teeth to the rim ;
Fig. 6, is a perspective view of one of the teeth; and,
Fig. 7, is a perspective view of the wedge for the teeth.
A, is the centre of the wheel which can be mounted on a suitable shaft A'. This
centre, A, has a ring, a, and spokes, b, and in the ring are a series of orifices, c.
B, is the rim formed of an outer ring, D, and an inner ring, E, connected together
at intervals by tie picces, e. On the ring, E, is a flange E', having a series of
orifices. d, coinciding with the orifices, c, in the ring, a, of the centre, A. Transverso
bolts, G, pass through the flange, E', and the ring, a, thus securing the centre to the
rim.
The outer ring, D, has a series of radial tapered openings, g, in which are inserted
the teeth, I, made preferably of hard wood. These teeth are formed with lateral
extensions, i, adapted to rest on the ring, D, and project through the ring into the
space, r, between the rings, D, and, E, and have undercut shanks, i, and fitting
between the shanks of adjoining teeth are wedges, H, clearly shown in Fig. 7,
which firmly hold the teeth in their sockets, g.
By this arrangement of parts, the cog-wheel can be readily constructed and
repaired, and the rim and its cog teeth can be readily removed from the centre
without removing the shaft, and any one of the teeth can be removed from its socket
and replaced, without interfering with the other teeth of the wheel.
By having the rings, D, and, E, united by the tie pieces, e, a certain amount of
elasticity is obtained, together with the bolting of the centre to the ring, and the
insertion of elastic packing, n, between the two, as shown in Fig. 2, enables the use
of a cog constructed on this principle with great advantage in connection with
electric motors and especially with electric motor driven cars, as the gears run
much more smoothly and the sound is deadened to a certain extent by the elastic
packing.
Where the side of a tooth rests against the tie piece as shown in Fig. 3. that side
of the tooth is perfectly flat, while the opposite side is undercut to receive the
wedge.
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 I
claim is
1. The combination of the centre adapted to be secured to a shaft, a rim, transverse
bolts securing the rim to the centre, with detachable teeth having undercut shanks,
and keys adapted to secure the teeth to the ring, substantially as hereinbefore
described

page_text: 2. The combination of the centre, with rings D, and E, said ring E, secured to the
centre, and the ring D, having teeth and connected to the ring E, by tie pieces,
substantially as hereinbefore described.
3. The combination of the wheel centre having a series of orifices, rings D,
and E, tie pieces e, connecting the rings D, and E, together, a flange on the ring E,
having orifices, bolts passing through the orifices in the flange, and in the rim of the
centre, with detachable teeth secured to the ring D, substantially as hereinbefore
described.
4. The combination of the centre, the rim composed of two rings tied together,
transverse bolts securing the rim to the centre, with elastic packing between the rim
and centre, substantially as herein before set forth.
Dated this 18th day of June 1890.
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C., Agents for the Applicant.