Improvements in Gear Wheels.
Year: 1890

page_text: Date of Application, 21st July, 1890
Complete Specification Left, 21st Apr., 1891-Accepted, 23rd May, 1891
PROVISIONAL SPECIFICATION.
Improvements in Gear Wheels.
We CHARLES HENRY GUEST and LOUIS BARROW trading as Guest & Barrow
of Tower Works, Tower Road, Birmingham, in the County of Warwickshire,
Cycle Manufacturers, do hereby declare the nature of this invention to be as
follows:
:-
Our invention relates to gear wheels such as spur wheels or sprocket wheels, and
it consists in building up the said wheels of thin plates, the object being cheapness
of construction with exactness of finish.
In carrying our invention into practical effect, we take a series of steel or other
metal blanks, and by means of a suitable die we stamp or press out a series of forms
of the exact shape of the desired wheel. We then take as many of these forms as
are necessary for the desired width of the wheel, and we rivet or otherwise fix them
together.
It will be understood that the thickness of the blanks is controlled by the power
at hand to stamp or press them, it being essential that the forms should leave the
die clean and true.
Suitable bosses may be formed on the blanks for the outer forms of each wheel,
to give the desired length of eye, or the forms may consist of rings of teeth only for
attachment other than directly on to the axle.
In some cases we interpose plain circular forms between those having teeth so as
to make the teeth of skeleton form.
By this construction of gear we are enabled to ensure accuracy in the shape and
pitch of the teeth without the necessity of machining them.
Dated this 21st day of July 1890.
ROBT. ED. PHILLIPS, M.I.M.E.,
Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Gear Wheels.
We, CHARLES HENRY GUEST and LOUIS BARROW, trading as Guest and
Barrow, of Tower Works, Tower Road, Birmingham, in the County of Warwick-
shire, Cycle Manufacturers, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
Our invention relates to gear wheels such as spur wheels or sprocket wheels, and
it consists in building up the said wheels of thin plates, the object being cheapness
of construction combined with exactness of finish.
In carrying our invention into practical effect, we take a series of steel or other
suitable metal blanks, and by means of a suitable die we stamp or press out a series
of forms of the exact shape of the desired wheel. We then take as many of these
forms as are necessary for the desired width of the wheel and we rivet or otherwise
fix them together.
It will be understood that the thickness of the blanks is controlled by the power
at hand to stamp or press them, it being essential that the forms should leave the
die clean and true.
Suitable bosses may be formed on the blanks for the outer forms of each wheel to
give the desired length of eye, or the forms may consist of rings of teeth only for
attachment other than directly on to the axle.

page_text: In some cases we interpose plain circular forms between those having teeth so as
to make the teeth of skeleton form.
In order that our invention may be fully understood we will more particularly
describe it with the aid of the accompanying drawing, in which
Figure 1 is a view in side elevation, and Figure 2 a view in sectional elevation,
of sprocket or chain wheel constructed according to our invention and adapted
for attachment to the hub of the driving wheel of a cycle.
Figure 3 is a view in elevation of one of the forms out of which the wheel is
constructed, and
Figure 4 is a view in sectional elevation of a similar wheel constructed according
to our invention and adapted to be fixed to the axle of a cycle.
Throughout the several views similar parts are marked with like letters of
reference.
Each wheel is constructed of a number-two or more-forms A of the exact
shape of the desired wheel, the said forms being fixed together by rivets or
screws a a etc. as illustrated by the accompanying drawing. The forms are stamped
or pressed out of blanks of sheet steel or other suitable metal. These blanks may
be of any thickness, the width of the chain wheel being made up of the necessary
number of stamped forms. After the forms are rivetted or screwed together they
may be either galvanized or tinned to make the whole homogeneous.
When the gear wheel is intended to be keyed or otherwise fixed direct on to an
axle the eye of the wheel may be made wider by flanging some of the forms as
shown by Figure 4 of the accompanying drawing, or by using plain circular forms
on the outside of the shaped forms.
By this construction of gear wheel we are enabled to ensure accuracy in the
shape and pitch of the teeth, without the necessity of machining them.
Having now described and ascertained the nature of our said invention and in
what manner the same. is to be performed we declare that what we claim is :-
First. The improved method of constructing gear wheels, substantially as set
forth.
Second. A gear wheel composed of two or more forms of identical form and
shape, stamped or pressed out of sheet metal and rivetted or screwed together, as
set forth.
Third. A gear wheel constructed out of two or more stamped or pressed out
sheet metal forms-according to the width of wheel required-rivetted or screwed
together, as and for the purpose set forth.
Dated this 21st day of April 1891.
ROBT. ED. PHILLIPS, M.I.M.E.,
Consulting Engineer and Patent Agent,
70, Chancery Lane, London, W.C., Agent for Applicants.