Improvements in or relating to Driving Gear for Cycles.
Year: 1895

page_text: Date of Application, 4th Jan., 1895
Complete Specification Left, 4th Oct., 1895-Accepted, 9th Nov., 1895
Improvements in or relating to Driving Gear for Cycles.
I, LIONEL REUBEN EDMUNDS of 44 Harding Street, Upper Parliament Street,
Liverpool in the County of Lancaster, Engineer, do hereby declare the nature of
this invention to be as follows:-
The object of this invention is to provide a driving gearing for bicycles, tricycles
or the like, which will enable a rider to drive his machine at a greater speed with
no greater exertion than hitherto.
The invention provides means whereby the operative length of the crank can be
varied in such a way that a greater leverage is obtained on the down-stroke tban
during the up-stroke.
In carrying my invention into effect, the plan I prefer is to pivot to the end of
each crank an elongation or arm, carrying the treadle by which the rider propels
the machine. On the pivot which couples the arm to the main portion of the
crank, I mount a chain wheel and fasten it to the arm in such a manner that
neither can revolve without the other. This chain wheel is geared to a non-rotatable
chain wheel by means of a chain, which is preferably fixed to the frame and
arranged concentric with the crank axle, and thus if the crank be rotated, the arm
will also be carried round with it, and at same time be rotated on its pivot, making
one complete revolution on its pivot for each revolution of the crank.
The mode of action is as follows:
:-
In driving the machine, the main portion of the crank will drive the machine in
the usual manner by chain and chain wheels or otherwise. The arm is geared up
to the stationary chain wheel on the frame in the manner described so that it will
assume various positions during the revolution of the crank and will approach or
recede from the centre on which the crank rotates. Thus, for example, in the
middle of the down-stroke the crank with its arm will be fully distended so as to
provide the fullest possible leverage; at the bottom of the stroke the arm will
stand at right angles to the crank, thus reducing the leverage somewhat; at the
middle of the up-stroke the arm will be turned back upon the crank so as to be in
proximity to the crank axle and provide little or no leverage at all, while as the
crank ascends, the arm will again recede from the axle, giving more leverage until
it becomes fully extended again during the down-stroke. On the down-stroke
therefore a much greater leverage can be obtained than on the up-stroke of the
crank, the latter being practically a dead point so far as its influence in propelling
the cycle is concerned, and moreover this improved result is obtained without
necessarily increasing the length of stroke, as the treadles travel in a path which
is not concentric with the crank axle. In point of fact the stroke might be even
shorter than hitherto, and yet a better result obtained.
I have described one way in which my invention can be carried into effect, but I
wish it understood that I do not confine myself to the exact arrangement and
mechanism herein before described, as this may be altered without departing from
the spirit of the invention, thus for instance toothed wheels may be employed
instead of the chain gearing or it may take other forms well known to mechanics,
whereby the same results may be obtained.
Dated this 3rd day of Jannary 1895
WM. P. THOMPSON & Co.,
Of 6 Lord Street, Liverpool, Patent Agents for the Applicant.

page_text: Improvements in or relating to Driving Gear for Cycles.
I, LIONEL REUBEN EDMUNDS of 44 Harding Street, Upper Parliament Street,
Liverpool in the County of Lancaster, 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 a driving gearing for bicycles, tricycles
or the like, which will enable a rider to drive his machine at a greater speed with
no greater exertion than hitherto.
The invention provides means whereby the operative length of the crank can be
varied in such a way that a greater leverage is obtained on the down-stroke than
during the up-stroke.
It will be understood from the following description, reference being had to the
accompanying drawings, in which,
Figure 1 is a front elevation of the driving gear,
Figure 2 a plan, and
Figure 3 a detail view of the fixed chain wheel.
In carrying my invention into effect, I pivot to the end of each crank A an
elongation or arm B, carrying the treadle C by which the rider propels the
machine. On the pivot which couples the arm B to the main portion of the
crank A, mount a chain wheel D and fasten it to the axis of the arm B in such
a manner that neither can revolve without the other. This chain wheel D is
geared to a non-rotatable chain wheel E by means of a chain F, the said wheel E
being fixed to the frame and arranged concentric with the crank axle G. Thus
the crank and arm rotate together but the arm B rotates at same time on its pivot,
making one complete revolution on its pivot for each revolution of the crank A.
H are the wheels of the machine.
The mode of action is as follows:
In driving the machine, the main portion of the crank A. will drive the machine
in the usual manner by chain H¹ and chain wheels I or otherwise. The arm B is
geared up to the stationary chain wheel E on the frame in the manner described
so that it will assume various positions during the revolution of the crank and will
approach or recede from the axis G on which the crank A rotates. Thus, for
example, in the middle of the down-stroke the crank A with its arm B will be
fully distended so as to provide the fullest possible leverage; at the bottom of the
stroke the arm will stand at right angles to the crank, thus reducing the leverage
somewhat at the middle of the up-stroke the arm will be turned back upon the
crank so as to be in proximity to the crank axle G and provide little or no
leverage at all, while as the crank ascends, the arm will again recede from the
axle, giving more leverage until it becomes fully extended again during the down-
stroke. On the down-stroke therefore a much greater leverage can be obtained
than on the up-stroke of the crank, the latter being practically a dead point so far
as its influence in propelling the cycle is concerned, and moreover this improved
result is obtained without necessarily increasing the length of stroke, as the
treadles travel in a path which is not concentric with the crank axle. In
point of fact the stroke might be even shorter than hitherto, and yet a better
result obtained.
I have described one way in which my invention can be carried into effect, but
I wish it understood that I do not confine myself to the exact arrangement and
mechanism herein before described, as this may be altered without departing from
the spirit of the invention, thus for instance toothed wheels may be employed
instead of the chain gearing or it may take other forms well known to mechanics
whereby the same results may be obtained.

page_text: 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. The improvement in driving gear for cycles, which consists in providing in
combination with each driving crank an elongation or arm carrying the treadle,
said arm being pivotted to the end of the crank and geared to a non-rotatable
chain wheel on the crank axis by means of a chain, whereby the arm will rotate
on its own axis as well as around the crank axis and thus vary the operative length
of the crank in such a way that a greater leverage is obtained on the down stroke
than during the up-stroke.
2. In driving gear for cycles, the combination with the driving axle and crank
mounted thereon, of arms pivotted to the cranks and carrying the treadles, and
mechanism such as chain wheels D and E and chain F or other suitable device for
automatically varying the position of the treadles relatively to the cranks,
whereby greater leverage can be obtained on the down-stroke than during the
up-stroke of the cranks substantially as described.
3. The general combined arrangement and construction of parts forming my
improved cycle gear substantially as described.
Dated this 3rd day of October 1895.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Birmingham, and London, Patent Agents.