Improvements relating to Wheel Gearing.
Year: 1890

page_text: Date of Application, 13th Jan., 1890
Complete Specification Left, 13th Oct., 1890-Accepted, 15th Nov., 1890
PROVISIONAL SPECIFICATION.
Improvements relating to Wheel Gearing.
I, JOHN HOOD, of Port Elphinstone, Inverurie, N.B., Engineer, do hereby declare
the nature of this invention to be as follows:-
The object of this invention is to provide wheel gearing with strong and noiseless*
yielding cogs or teeth to take the place of the solid wooden cogs or teeth at present
used on mortise wheels for high speed toothed gear, and which wooden cogs or teeth
quickly wear out.
According to this invention the cogs or teeth are formed of two steel plates with a
piece of india-rubber, woodite, wood, or other elastic or semi-elastic non-sonorous
material, between them, or they may be formed of two steel plates curved or bent so
as to be of a springy or resilient nature, thus obviating the necessity of placing any
kind of elastic or non-elastic material between them. These cogs or teeth may be
formed so as to fit into the mortises in an ordinary. mortise wheel, or they may be
fitted into a cast or malleable iron, steel, or other wheel constructed specially to
receive them.
CASTLE SMITH,
Per F. W. Golby,
"Invention" Office, 54, Fleet Street, London, E.C., Agent for the Applicant,
COMPLETE SPECIFICATION.
Improvements relating to Wheel Gearing.
I, JOHN HOOD, of Port Elphinstone, Inverurie, N.B., Engineer, 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 :-
The object of this invention is to provide wheel gearing with strong and noiseless
yielding cogs or teeth to take the place of the solid wooden cogs or teeth at present
used on mortise wheels for high speed toothed gear and which wooden cogs or teeth
quickly wear out.
According to this invention the cogs or teeth are formed of two metallic plates,
preferably of steel with a piece of india-rubber, woodite, wood, or other elastic or
semi-elastic non-sonorous material between them, or they may be formed of two
metallic, preferably steel, plates curved or bent so as to be of a springy or resilient
nature, thus obviating the necessity of placing any kind of elastic or semi-elastio
material between them. These cogs or teeth may be formed so as to fit into the
mortises in an ordinary mortise wheel or they may be fitted into, or on, the rim
of a cast or malleable iron, steel, or other wheel constructed specially to receive
them.
In the accompanying drawings
Figure 1 is a side elevation and
Figure 2 is a face or front elevation of a cog or tooth constructed in accordance
with my invention ;
Figure 3 is a cross section of the rim of a mortise wheel with my improved cogs
or teeth fitted therein, and
Figure 4 is a sectional elevation of part of a mortise wheel rim showing examples
of the different shapes and methods of fixing the cogs or teeth constructed in
accordance with my invention.
:

page_text: In Figures 1 to 3, A A are the metal plates made to the shape or form of the cog
or teeth as shewn, B is the backing or packing of india-rubber, woodite, wood, or
other elastic or semi-elastic non-sonorous material, and C is the pin or key for securing
the cog or teeth to the rim of the wheel.
In Figure 4 the teeth or cogs are marked from 1) to L successively. D and E
are turned over at their ends so that one plate or side of each of two adjacent teeth
may be secured by one key C shaped so as to pass between them as shewn. This
key may be solid or it may be made hollow, and if desired filled in with the packing
material similar to that used with the cogs or teeth themselves. The cog E has
the backing or packing E only in the upper part where it is held in position by
projections M on the plates A. In the cog F shewn partly in section, a side aperture
or apertures N is or are made in the plates into which the backing or packing B
projects and is thus secured; this cog is shewn fixed with a triangular key. In the
cog G the outside is formed from one metallic plate A bent or curved to the desired
shape of the cog or tooth, the backing B is in position between the sides of the cog,
and the finished cog secured to the wheel rim by a U shaped key C. H shews a
similar form of cog but with the ends of the plate joined at the root of the cog or
tooth instead of at its point as shewn in G, the key used being of a D shape. Jis
a cog formed of one plate A, closed at the bottom and having its driving face made
of the packing material B which is shaped to the desired contour of the driving face
of the cog or tooth as shewn. In this case the material B will be such as will
withstand the wear, while the necessary strength of the cog is obtained by the
metallic plate A at the back. The plate A is held in the rim of the mortise wheel
by the usual key C, while the material B is held by a rivet O passing through the
plate A, or by the plate A being indented into corresponding recesses in the material B.
At K the plates A are bent to form a spring, and the space between them may or
may not be filled with the backing or packing material as desired. This cog is shewn
fixed with a hollow key C, it may however be fixed by a pin C¹ in the centre of the
rim of the wheel as shewn by the dotted lines. L shews another form of my
invention wherein a metal spring P is interposed between the two plates A the
backing or packing material being dispensed with. When the wheel drives in both
directions, or is subjected to much backlash, two similar springs placed back to back
may be used.
Two or more cog wheels made in accordance with this invention may be placed
end to end to form a wheel with a broad face, or they may be placed stepwise to
formn what is commonly known as a step wheel. Gear wheels provided with these
cogs can work with similar wheels, or with wheels having the teeth cast on the rim
in the usual manner, having the teeth of the necessary shape and of the same pitch,
and can be run at a high speed without shock or noise.
Although in Figure 4 I have shewn various shapes of the cogs, and different
methods of fixing the material B therein, 1 wish it to be well understood that they are
furnished as examples only as the invention is capable of considerable modification
without departing from the essential features thereof. I also wish it to be clearly
understood that I make no claim to any particular form or method of securing or
fixing the cogs to the rim of the wheel as this is a mechanical detail which forms no
part of my invention.
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) A cog or tooth for wheel gearing consisting of a metallic plate or plates,
preferably of steel, of the desired shape forming the sides or shell of the cog, between,
within, or attached to, which is a backing or packing of india-rubber or other elastic
or semi-elastic non-sonorous material, substantially as and for the purpose herein-
before set forth and illustrated in the accompanying drawings.
.(2) The modified form of my invention wherein the metallic sides of the cog are
curved or bent, or internal metallic springs are provided for the purpose of forming

page_text: a strong and yielding cog or tooth, substantially as described and shewn with
reference to K and L in Figure 4 of the accompanying drawings.
(3) My improvements in cogs or teeth for wheel gearing substantially as described.
Dated this 13th day of October 1890.
ČASTLE SMITH,
Per F. W. Golby,
"Invention" Office, 54, Fleet Street, London, E.C., Agent for the Applicant.