ment in Driving Gear for Cycles.
Year: 1896

page_text: An Improvement
I JOSEPH ALDRED of 159 Leigh Road, Atherton, near Manchester, in the County
of Lancaster, Collier, do hereby declare the nature of this invention to be as
follows:-
This invention is applicable to the chain gear used for driving cycles, the object
of the invention being to enable the machine to be driven at a high velocity for
racing purposes and also to be readily altered to a greatly reduced speed for
ordinary road riding.
For racing purposes I employ a double chain gear that is to say between the
large sprocket wheel on the crankshaft and the small sprocket wheel on the driving
wheel spindle I fix on the bottom tube of the frame a pedestal carrying a short
spindle on which are fixed two sprocket wheels, a small one (on one side of the
pedestal) opposite to the large sprocket wheel on the crankshaft, and a larger one
(on the other side of the pedestal) opposite to the small one on the driving wheel
spindle.
I employ two driving chains one giving motion from the crankshaft to the
intermediate short spindle and the other from the short spindle to the driving
wheel, by which a very high velocity can be obtained, say for example, if the large
wheels are twice the diameter of the small wheels then each revolution of the pedals
will give four revolutions of the driving wheel and so on.
When the machine is required to be converted for ordinary road riding purposes
the pedestal carrying the intermediate short spindle and its two sprocket wheels are
removed, and the driving wheel sprocket is driven direct from the crank shaft
sprocket in the ordinary manner by a single chain of suitable length, and the
driving wheel will then run two to one.
If desired one of the short chains may be lengthened for this purpose by the
addition of a suitable number of links.
Dated this 11th day of August 1896.
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Driving Gear for Cycles.
I JOSEPH ALDRED, of 159 Leigh Road, Atherton, near Manchester, in the
County of Lancaster, Collier, 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 is applicable to the chain gear used for driving cycles, the object
of the invention being to enable the machine to be driven at a high velocity for

page_text: racing purposes, and also to be readily altered to a greatly reduced speed for
ordinary road riding.
The nature of my said invention and the manner in which the same is to be
performed or carried into practical effect will be readily understood on reference
to the annexed sheet of drawings and the following explanation thereof :-
Fig. 1 on the drawings is a side elevation, and Fig. 2 a plan view (shown partly
in section) of so much of the chain driving gear of a cycle as is necessary to
illustrate my invention.
According to my invention I employ for racing purposes a double or compound
chain gear, that is to say, between the large sprocket wheel a on the crank shaft b
and the small sprocket wheel c on the spindle of the driving wheel d of the cycle,
I fix on the bottom tube or chain-stays e of the frame a pedestal f (see also cross
section Fig. 3) carrying a short spindle g, on which are fixed two sprocket wheels,
a small one on one side of the pedestal opposite to the large spocket wheel a
on the crank shaft, and a larger one i on the other side of the pedestal opposite
the small one c on the spindle of the driving wheel d.
I employ two driving chains, one k giving motion from the crank shaft b to
the intermediate short spindle, and the other one from the short spindle g to
the driving wheel d of the machine, by which means a very high velocity can be
obtained, say for example, if the large sprocket wheels are twice the diameter of
the small ones, then each revolution of the crank axle will give four revolutions
of the driving wheel d and so on in proportion.
When the machine is required to be converted for ordinary road riding purposes
the pedestal f, carrying the intermediate short spindle y with its two sprocket
wheels and are removed, the driving wheel d is taken out and reversed so as
to bring its sprocket pinion c in a line with the large sprocket wheel a on the
crank shaft b, and the driving sprocket wheel c can then be driven direct from the
crankshaft sprocket whool a in the ordinary manner by a single chain of suitable
length, and the driving wheel d will then run two to one.
Or, if desired, one of the short chains k or may be lengthened for this purpose
by the addition thereto of a suitable number of links.
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 :-
The improvement in driving gear for cycles consisting in the adaptation thereto
of compound chain driving gear so arranged that it can readily be converted into
simple chain gear when desired, substantially as hereinbefore described and
illustrated by the drawings annexed.
Dated this 8th love of Ma. 1907
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicant.