Improvements in Driving Gear for Cycles.
Year: 1895

page_text: Date of Application, 8th Oct., 1895-Accepted, 28th Dec., 1895
COMPLETE SPECIFICATION.
Improvements in Driving Gear for Cycles.
We, GEORGE SINGER, residing at 56 Gerrard Street, West, in the City of
Toronto in the County of York and Province of Ontario, Blacksmith, PETER
JAMES SMITH, residing at 228 Sackville Street, in the said City of Toronto,
Blacksmith, and SEWARD RUSSELL YOUNG, residing at 156 Wilton Avenue, in the
said City of Toronto, Blacksmith, 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 certain new and useful improvements in driving gear
for cycles, and relates more particularly to certain new and useful improvements
in the driving cranks, whereby an increase of power may be obtained on that
portion of the stroke of the driving crank where it is possible to apply the driving
force with the greatest possible advantage, and to so construct the driving crank
that on the backward stroke of the crank it will automatically be shortened, in
order that the pedal will reach its topmost position by the shortest possible course,
and the object of the invention is to develop the highest speed with the least
expenditure of power; and the invention consists essentially of rigidly securing
an eccentric disk at each end of the crank axle bracket, extending the crank axle
beyond each of the said eccentric disks, rigidly securing a crank member to each
end of the crank axle on the outer side of the said disks, providing each crank
member with a sliding sleeve, to the outer end of which is connected the pedal pin
and pedal, and providing the eccentric disk with an eccentric strap, to which is
connected one end of an eccentric rod, whilst the opposite end of the eccentric
rod is connected to the sliding sleeve, in order that the sleeve will be worked
respectively away from or towards the hub of the crank member during the
revolution of the driving crank, to respectively increase or diminish the length of
the driving crank, in order that the leverage may be increased where the driving
force is applied, and decreased where the driving force is removed from the driving
crank the whole device being hereinafter more fully set forth and
particularly pointed out in the claims.
In the drawings:
more
Fig. 1 is a perspective view of a section of the frame of the bicycle, showing the
application of our improvements.
Fig. 2 is a view showing the driving crank in its elongated position.
Fig. 3 is a view showing it in its shortenel position.
Fig. 4 is a section through the driving crank.
Like letters of reference refer to like parts throughout the Specification and
drawings.
Supported by the lower reach bar A, the lower rear fork bars B, and the
saddle pillar bar or standard C, is the crank axle bracket D. Journalled within
the crank axle bracket D is the crank axle E. Connected to the frame of the
bicycle at one end of the crank axle bracket D is a disk F, and connected to the
said frame at the opposite end of the crank axle bracket is a similar disk F¹,
arranged concentric with each other, and eccentric to the crank axle E. Rigidly
mounted on one end of the crank axle E is the hub G of the crank member H
whilst mounted on the opposite end of the crank axle E is the hub I of the crank
member J. The hubs G-I and cranks H-J correspond in every respect with
Sliding on the crank H. and extending from the hub G to a point
each other.

page_text: slightly beyond the end of the crank H, is a sleeve K, the outer end of which is
fitted to receive the pedal pin L of the pedal M. The other crank J is provided
with a similar sleeve N fitted to receive th pedal pin O of the pedal P. The
sleeves K-N correspond with each other in all respects, regarding size, shape and
appearance, and location, and are so constructed as to slide freely on their
respective cranks H-J. To provide an easy sliding surface for the sleeve
I provide the crank member with a series of bearing balls H¹ so arranged as to be
prevented from becoming displaced under ordinary conditions. The periphery of
the eccentric disk F is fitted to receive bearing balls Q, and working around the
periphery of the eccentric disk F, and on the bearing balls Q, is an eccentric
strap R.
Connected to the eccentric strap R is one end of an eccentric rod S,
whilst the opposite end of the eccentric rod S is connected to a pin T connected
to the sleeve K. The periphery of the eccentric disk F' is fitted to receive a
series of bearing balls U, and working around the periphery of the eccentric
disk Fon the bearing balls U is an eccentric strap V. Connected to
the eccentric strap V is one end of an eccentric rod W, whilst the other end
of the eccentric rod W is connected to a pin X connected to the sleeve N.
The revolution of the crank axle and cranks causes the revolution of the
eccentric straps around the peripheries of their respective eccentric disks, and the
travel of the eccentric straps around the said eccentric disks cause their respective
sleeves to more away from or towards the hubs of their respective cranks, to
respectively lengthen or shorten the driving cranks. The eccentrics are so
arranged that the sleeves are moved from the hub as the crank comes into its
upright position, and is continued to be moved from the hub after passing its
uppermost position, until it has reached a position on its downward course
approximately equal to one third of its entire revolution, when it commences to
return again to the hub. It might here be stated that the application of the
driving power is applied to the driving crank immediately after passing its upper-
most position and until it has completed about one-third of its revolution, when
the position of the crank renders it impossible to apply the full driving power.
Whilst the crank is in a position to receive the full benefit of the driving power it
is advisable to have the greatest leverage possible, in order that the driving power
can be applied so that the greatest possible results are attainable, and immediately
after the crank has passed into a position where it is impossible to further apply
driving power to the crank the sleeve commences to move towards the hub.
Having now particularly described and ascertained the nature of our said inven-
tion, we hereby declare that what we claim is:
1. In a driving gear, the combination, with the axle, of a crank capable of
extension during one portion of its stroke, and contraction during the remainder,
substantially as specified.
2. In a driving gear the combination with the axle of a crank consisting of two
sections, one section connected to the axle, the other section slidingly moveable on
the first section, and means for sliding the second section on the first section during
the revolution of the crank, to respectively lengthen or contract it, substantially
as specified.
3. In a driving gear, the combination, with the axle of a crank comprised of a
crank member connected to the axle, and a sleeve slidingly moveable on the crank
member, during the revolution of the crank, substantially as specified.
4. In a driving gear, the combination with the axle of a crank comprised of a
crank member connected to the axle, a sleeve slidingly moveable on the crank
member during the revolution of the crank, and means for slidingly moving the
sleeve on the crank member, substantially as specified.
5. In a driving gear, the combination with the axle of a crank comprised of a
crank member connected to the axle, a sleeve slidingly moveable on the crank
member, pedal conuected to the sleeve, a disk connected to the frame, eccentric
to the axle, an eccentric strap encircling the said disk, an eccentric rod connected

page_text: to the strap and to the sleeve whereby the crank is lengthened or contracted during
its revolution, substantially as specified.
6. In a driving gear, the combination with the axle of a crank comprised of a
crank member connected to the axle, a sleeve slidingly moveable on the crank
member, a pedal connected to the sleeve, a disk connected to the frame, eccentric
to the axle, an eccentric strap encircling the said disk, an eccentric rod connected
to the strap and to the sleeve whereby the crank is lengthened or contracted during
its revolution, and bearing balls interposed between the eccentric strap and the
eccentric disk, substantially as specified.
7. In a driving gear, the combination with the axle of a crank comprised of a
crank member connected to the axle, a sleeve slidingly moveable on the crank
member, a pedal connected to the sleeve, a disk connected to the frame, eccentric
to the axle, an eccentric strap encircling the said disk, an eccentric rod connected
to the strap and to the sleeve whereby the crank is lengthened or contracted during
its revolution, bearing balls interposed between the eccentric strap and the
eccentric disk, and bearing balls interposed between the sleeve and the crank
member, substantially as specified.
Dated this 8th day of October 1895.
HUGHES & YOUNG,
23 Coleman Street, London, E.C., Agents for Applicants.