Year: 1894

page_text: .Date of Application, 20th Oct., 1894
Complete Specification Left, 13th July, 1895-Accepted, 31st Aug., 1895
Goals for yores.
We, JOSEPH FOXCROFT of Calabria Road Highbury, Middlesex, ARTHUR
BLANCHARD Turnpike Lane Hornsey, and HARRY WOOD, Wilberforce Road,
South Hornsey, all Engineers do hereby declare the nature of this invention to be
as follows:-
:-
This invention relates to improvements in the driving mechanism of cycles
and applies to any class of the crank driven kind either with or without chain
gear.
It has for its object to provide a means to compensate for the varying leverage
of the cranks and thus to obtain a more constant pressure throughout the stroke
also a method of overcoming the dead centre and consequently enabling the rider
to obtain a perfectly continuous action in pedalling. In order to effect this
according to our invention we employ a novel arrangement of gearing in the
following nanner: Instead of the cranks as is usual, being fixed rigidly to the
gear axle, we employ either two distinct axles, or one axle having one crank fixed
and the other carried by means of a sleeve in such a manner as to allow either
crank to revolve independently. We then mount on each axle a gear wheel having
the form of an ellipse and fixed on the said axle eccentrically so that the axis of
rotation is through one of the foci of the ellipse, each crank therefore carries round
its own wheel independently, each wheel being in the same position relative to the
crank upon which it is fixed. We now either by chain or toothed gearing put the
said wheels in connection. with two other exactly similar wheels which are.mounted
rigidly. on a counter spindle so that they revolve together, but with their eccentricity
in opposite directions, the said counter spindle is connected by means of any suitable
gearing to the driving wheel of the machine. By this method it will be seen that
we obtain a continuously varying motion of the pedals assuming the machine to be
running at a constant speed the cranks decrease in speed corresponding to an
increase in gear during one half revolution and increase in speed corresponding to
a decrease in gear during the other half. Thus we are enabled to obtain a quick
return motion for the cranks when ascending causing the pedal to come into action
before the other reaches the dead centre, also the position of highest gear becomes
the position of greatest advantage in leverage.
Dated this 20th day of October 1894.
JOSEPH FOXCROFT.
ARTHUR BLANCHARD.
HARRY WOOD.

page_text: mprovements in Gears for Cycles.
We, JOSEPH FOXCROFT, of 70 Calabria Road Highbury, ARTHUR BLANCHARD
107 Turnpike Lane, Hornsey, and HARRY WOOD 133 Wilberforce Road Finsbury
Park all in the County of Middlesex England, Engineers 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 :-
This invention relates to improvements in the driving mechanism of cycles and
applies to any class of machine of the crank driven kind either with or without
chain gear.
It has for its object a means to compensate for the varying leverage of the
cranks and thus to obtain a more constant pressure throughout the stroke, also
a means of overcoming the dead centre & consequently enabling the rider to obtain
a perfectly continuous action in pedalling.
In order to effect this according to our invention we employ a novel arrangement
of gearing in the following manner.
Instead of the cranks as is usual being fixed rigidly to the gear axle, we employ
either two distinct axles, or one axle having one crank fixed & the other
carried by a sleeve in such a manner as to allow either crank to revolve
independent of the other.
We then mount on each axle a gear wheel having the form of an ellipse & fix on
the said axle eccentrically so that the axis of rotation is through one of the foci of
the ellipse, each crank therefore carries round its own wheel independently, each
wheel being in the same position relative to the crank, upon which it is placed.
We now either by means of tooth or chain gearing put the wheels in gear with
two other but exactly similar wheels, to those aforesaid.
These second wheels are mounted on a counter spindle so that they revolve
together, but with their eccentricity in opposite directions the said counter
spindle being connected by means of any suitable gearing to the driving wheel of
the machine.
By this method it will be seen that we obtain a continuously varying motion of
the pedals. Assuming the machine to be running at an even speed the cranks
decrease in speed corresponding to an increase in gear, during one half revolution
& increase in speed corresponding to decrease in gear during the other half; thus
we are enabled to obtain a quick return motion for the cranks allowing the pedal
to come into action before the other has reached the dead centre; also the position
of the pedals corresponding to the highest gear becomes the position of greatest
advantage with respect to leverage of the cranks.
Our invention will be better understood by reference to the annexed drawings,
which show our invention as applied to a common safety bicycle from which it will
be obvious that with slight modification it may be applied to geared ordinaries
tricycles & the like.
Fig. II shows a section & Fig. I a side elevation. In Fig. II the crank A. is
connected by the spindle B. to the eccentric spur wheel C. The crank D. is
connected by a sleeve E. to eccentric wheel F. These wheels which are elliptical
in shape, are geared into two similar ones G. & H. mounted rigidly on a counter
spindle J. the motion of which is transmitted to the driving chain wheel K. by
means of the circular concentric spur wheels L. & M. & the sleeve P. which
revolves on but is independent of the crank spindle B. The whole of the gear
wheels supported in suitable bearings are enclosed in the oil-tight box R. which is
brazed to the frame tubes & forms the bottom bracket of the machine from this it
will be understood that if we assume the machine & consequently the axle J.
to be running at a constant speed the cranks owing to the eccentricity of the

page_text: wheels C. F. G. H. will obtain a varying speed, each crank moving more slowly
on the downward than on the upward stroke & thus when one crank descending
reaches the dead centre, the other by moving more quickly in its ascent will have
passed the centre & will in consequence be in a position for pedalling.
Having now particularly described & ascertained the nature of our said
invention & in what manner it is to be performed we declare that what we
claim is,
In the driving mechanism of cycles, eccentric elliptical gearing driven by cranks
working independent of each other substantially as and for the purpose herein
described.
JOSEPH FOXCROFT.
ARTHUR BLANCHARD.
HARRY WOOD.
JOSEPH FOXCROFT.
ARTHUR BLANCHARD.
HARRY WOOD.