Improvement in Cycle Gearing.
Year: 1894

page_text: Date of Application, 17th July, 1894
Complete Specification Left, 26th Mar., 1895-Accepted, 27th Apr., 1895
PROVISIONAL SPECIFICATION.
Improvement in Cycle Gearing.
WALTER PARKER 'SMITH, 10 Strathleven Road Acre Lane, Brixton, Surrey,
Mechanical Engineer, and ÉMILY GEAR 118 Acre Lane, Brixton, Surrey,
Tobacconist, do hereby declare the nature of this invention to be as follows:-
A tail piece or bracket is extended from, and attached to the framing, or if
desired the framing may be extended. To it is mounted, free to revolve, an idle
pulley, around which the driving chain is carried. The position of the idle pulley
and also its diameter is determined so as to permit the driving chain gearing
with suitable teeth formed on the pinion of the axle to be driven. The chain
and pinion being arranged to work as a "rack and pinion." Either the upper,
lower, or both sides of the pinion may be employed as desired. The idle pulley
may be made either plain or toothed.
Another arrangement is to utilize the idle pulley as a countershaft. In this
case it is geared to the axle pinion.
The relative diameters of idle pulley and pinion being determined so as to
permit the driving chain working clear of the pinion.
Dated this 16th day of July 1894.
WALTER PARKER SMITH.
EMILY GEAR.
Improvement in Cycle Gearing.
We, WALTER PARKER SMITH, 10 Strathleven Road, Acre Lane, Brixton,
Surrey, Mechanical Engineer, and EMILY GEAR, 118 Acre Lane, Brixton
Surrey, Tobacconist, 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 chain gear of a velocipede usually consists of a sprocket wheel on the pedal
axle connected by a chain to a smaller sprocket wheel ou the axle of the driving
wheel. As the chain passes about half round the latter wheel, the teeth on the
slack side, while they are inoperative for the purpose of driving tend to impede the
movement of the chain as it has to engage upon them.
Our invention relates to means of obviating this impeding action by confining
the bearing of the chain to only a small part of the circumference of the wheel
when it exerts its driving force, as we shall describe referring to the accompanying
drawing which represents a side view of the chain gear for a bicycle arranged
according to our invention.
A is the pedal axle, B B the pedals, C the sprocket wheel driven by the pedals,
D part of the framing forming a strut between the pedal axle A and the axle E of
the driving wheel F.
On the part of the frame which has bearings for the driving axle E we fix &
bracket G in which mount a guide wheel H, which may be a sprocket wheel or a

page_text: plain pulley. It is so situated that the chain L which moves in the direction of the
arrows is guided away from the wheel F until it reaches a point f of its circum-
ference such that there is only a fraction of the circumference from f to f¹ engaged
by the chain.
We fit the bearing of the stud on which the pulley H revolves so that it can
slide in a slot of the bracket G, and we provide a bolt and a nut K by which we
can adjust the stud nearer to or farther from the axle E, the pulley H thus serving
for tightening the chain as well as guiding it for the purpose set forth.
Although we have described the guide wheel H applied only to one of the
sprocket wheels, it might obviously be applied to the other, or both wheels might
have such guide wheels applied to them.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what
we claim is :-
In combination with the chain gear of a velocipede, a guide wheel arranged and
operating, substantially as and for the purpose set forth.
Dated this 26th day of March 1895.
ABEL & IMRAY,
Agents for the Applicants.