Improved Driving Mechanism for Cycles.
Year: 1896

page_text: Date of Application, 13th Feb., 1896-Accepted, 4th Apr., 1896
Improved Driving Mechanism for Cycles.
I, WILLIAM JAMES STEVENSON STRANGE, of Dormer Lodge, Leamington, in
the County of Warwick, Gentleman, 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 the present invention is to provide simple and effective driving
mechanism for cycles whereby a more comfortable leg action and ease of propulsion
are obtained.
I will now fully describe my invention and the manner of performing the same
having reference to the accompanying drawings in which similar letters refer to
corresponding parts in all the figures and wherein :-
Fig. 1 is a diagram illustrating in side elevation the application of my
to a rear driving safety bicycle.
Figs. 2 and 3 are details.
invention
a is the driving wheel which revolves in convenient bearings carried by the
frame c.
d is the hub chain wheel and e is a second chain wheel also mounted in
suitable bearings carried by the part b of the frame c and connected with d by the
pitch chain f. g is a foot lever terminating at one end in a pedal h of suitable
construction and pivotally connected at i with a link k which in turn is pivotally
connected at l with the extension cl of the frame c. m is a pin fixed to and
extending inwards from the lever g said pin engaging with a slot or hole formed in
a crank secured upon the axis of the chain wheel e. Duplicate driving mechanism
to that above described is as will of course be understood provided upon the
opposite side of the cycle. The cycle is driven by the rotation of the crank n and
chain wheel e connected therewith effected through the foot lever g and pin m.
The path followed by the feet in driving the machine is indicated by the dotted
ellipse.
In order to assist the cranks past the dead centres I may employ springs 0 0 1
the spring o being connected at one end with and exerting its force to lift the
lever g whilst the spring o1 is connected at one end with and exerts its force to
draw forwards the link k. The other ends of both springs are connected with some
convenient part of the frame, as at p.
I do not however consider the employment
of these springs to be absolutely essential.
My invention further relates to meaus whereby I am enabled to reduce the
upward throw of the levers 9 said means being clearly illustrated in Figs. 2
and 3.
Referring to these last mentioned figures, q is a slot formed in the crank n
within which slot slides freely a bearing r which receives the pin m on the lever g.
s is a spring which tends to keep the bearing r at that end of the slot nearest to
the crank axis. The strength of this spring is such that the pressure of the foot
on the downward stroke will compress the same and force the bearing r to the
bottom of the slot as clearly shewn in Fig. 2 where the dotted line indicates the
position of the lever g, the full leverage of the crank is thus utilised during the
downstroke. Directly the downward pressure upon the lever g is relieved however
the spring s forces the bearing r inwards towards the crank axis thereby considerably
lessening the upward throw of the lever g as clearly shewn in Fig. 3 where the dotted
line indicates the position of the lever.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I would observe in conclusion
that I am aware that cycles have before been driven by means of foot levers in
lieu of by rotary action and that I do not therefore claim broadly this method of
driving cycles as forming any part of my invention but I declare that what I
claim is :-
1. Driving mechanism for cycles consisting of the combination of a foot lever
carrying a pedal at one end, a link pivotally connected with the other end of the
said foot lever and with the frame of the cycle, and a crank and chain wheel
rotated by a pin projecting from said lever, the said chain wheel being connected
by a pitch chain with the hub chain wheel and the mechanism being arranged in
duplicate upon either side of the cycle, substantially as described and illustrated.
2. In combination with the driving mechanism set forth in the preceding
claim, the springs o ol arranged as described, substantially as and for the purpose
-specified.
3. In lever driven cycles, the means whereby the upward throw of the levers is
reduced, substantially as described with reference to and illustrated in Figures 2
and 3 of the drawings.
Teted this 13th day of February 1896
E. P. ALEXANDER & SON,
Chartered Patent Agents,
19 Southampton Buildings, Chancery Lane, London, W.C., Agents.