Improvements in and connected with Propelling Mechanism for Cycles.
Year: 1899

page_text: COMPLETE SPECIFICATION.
Improvements in and connected with Propelling Mechanism for
Cycles.
I, CHARLES OLOF ANDERSON, of Butte, in the County of Silverbow and State
of Montana, United States of America, Gentleman, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be particu-
larly described and ascertained in and by the following statement:―
My invention relates to improvements in and connected with propelling
mechanism for cycles, and the object is to provide a mechanism which multiplies
the power exerted by the rider for the propulsion of the machine.
A further object of the invention is to reduce the wheel-base of the machine
by bringing the crank hanger and rear wheel in close relation so that the ele-
ments of the propelling mechanism may be proportioned to secure the increased
leverage and retain the arrangement of the pedal cranks at all times within the
reach of the rider.
With these ends in view, the invention consists in the novel combination of
elements and in the construction and arrangement of parts, which will be herein-
after fully described and claimed.
To enable others to understand the invention, I have illustrated the preferred
embodiment thereof in the accompanying drawing, forming a part of this speci-
fication, and in which-
Figure 1 is a side elevation of a bicycle equipped with my improvement and
showing the treadle levers and pedals in the same horizontal plane.
Figure 2 is a similar view with the levers and the pedals in the positions they
assume when the pedals shall have traveled a fragment of a circle.
Figure 3 is a vertical transverse section through the crank-hanger and crank-
shaft on the plane indicated by the dotted line 3-3 of Figure 2.
Figure 4 is a rear end elevation.
Figure
5 is a plan view of one of the propelling levers.
Figures 6 and 7 are enlarged detail views in rear and side elevation respec-
tively of the shiftable fulcrum for one of the levers.
Like numerals of reference denote like and corresponding parts in each of the
several figures of the drawing.
The frame, 10, of the bicycle embodying my invention is similar to ordinary
diamond-frame bicycles of the safety pattern, and it is equipped with a crank-
hanger, 11, a rear wheel, 12, the fork, 13, and the front wheel, 14. The hori-
zontal frame-fork, 10%, is extended beyond the bearing provided for the axle
of the rear wheel, and the rear extremity of this frame-fork is united or coupled
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page_text: to a hanger-bar, presently referred to, for the purpose of providing a strong
rigid support for the shiftable fulcrum rollers of the propelling levers, as will
hereinafter more fully appear. In constructing the frame of the bicycle, I pro-
pose to arrange the crank-hanger, 11, in such close relation to the tread of the
rear wheel that sufficient space is provided for clearance of the wheel; and in
practice it is designed that the face of the crank-hanger shall be within one-half
inch of the tread of the wheel instead of providing a space of five or six inches
between the crank hanger and wheel as in ordinary machines, thus reducing
the wheel-base.
The crank-shaft, 15, is journaled in the usual ball-bearings provided
within the crank-hanger, and the ends of this shaft have the radial
crank-arms 16, which extend in diametrically-opposite directions from the
crank-shaft. The free ends of the crank-arms have wrist-pins, 17, which are
connected with the propelling levers, 18, 19, the latter being disposed or arranged
on opposite sides of the machine in compact relation to the frame and rear wheel
thereof To provide for the proper connection of the wrist-pins to the levers and
reduce the friction and wear on the parts as much as possible, I provide the
propelling levers with ball-bearings, 20, which are secured or arranged on said
levers at points about five and one-half inches from the front extremities thereof,
although this exact proportion is not essential. The ball-bearings, 20, receive
the wrist-pins 17 of the crank-arms, and the lever and its appropriate crank-arm
is thus connected directly together so that the motion of each lever will be com-
municated by the crank to the crank-shaft. Instead of attaching the pedal
directly to the crank of the pedal-shaft as is usual in ordinary safety bicycles, I
apply the pedals, 22, to the short arms, 21, which are provided by the front ends
of the levers extending beyond the ball-bearings, 20, and wrist pins, 17, and each
crank of the shaft is thus increased in length by the short arms, 21, of the levers.
The rear frame-fork, 10%, is extended or carried backward, as at 23, rearward
from the axle of the hind-wheel, 12, and this extension of the frame-fork is
joined, as at 25, to the hanger-bar, 24. The hanger-bar is arched to lie over
the rear wheel, 12, and the front end thereof is firmly united to the upwardly-
inclined brace, 26, that extends from the rear wheel-hub and frame-fork, 10",
to the seat-post tube, the hanger-bar, 24, being secured in a suitable way to this
frame-brace at a point below the saddle. The rear end of the hanger-bar is
forked or bifurcated at 27, to be properly united with the rear terminals of the
frame-fork, 10"; and the horizontal shafts or arbors 28, are passed through the
joint, 25, between the frame-fork and the bifurcated end of the hanger-bar.
These shafts or arbors are supported by the hanger-bar one above the others in
the same vertical plane so as to occupy the same position relatively to the frame
at all times; and the ends of the shafts or arbors are extended or prolonged
beyond the bifurcated hanger-bar for the proper application thereto of the two
pairs of fulcrum rolls between which the rear ends of the propelling levers are
slidably supported. The fulcrum rolls for each of the propelling levers are
indicated more clearly in Figures 6 and 7 by the numerals, 29, 30 The fulcrum
rolls are mounted on the protruding portions of the shafts or arbors, 28, so as
to rotate freely, and in the peripheral working faces of these rolls are formed
coindent grooves that receive or accommodate the rear ends of the propelling
levers. The levers are fitted in the grooved rolls to be capable of a limited oscil-
lating movement in vertical planes and also of a sliding movement in a horizontal
plane, and the levers are retained or held in place by the grooved rolls which
permit the described oscillating and sliding play thereto. Each lever is thus
mounted in the rolls to travel with its crank-arm in the orbital path described
by the arm in its revolution with the shaft, and the rolls thus serve as a shiftable
fulcrum for the lever which accommodates itself to the changing positions of
the crank-arm.
Each propelling lever is curved or offset at a point intermediate of its length,

page_text: as at 31, see Figure 5, to permit the lever to have sufficient clearance with rela-
tion to the frame and the wheel-hub to avoid the lever striking the frame as it
travels with the crank arm.
A driving sprocket, 32, is secured to the crank shaft, a driven sprocket, 33, is
fixed to the rear wheel hub, and an endless sprocket chain, 34, is employed to
operatively connect the crank-shaft with the rear wheel hub. This transmitting
mechanism is familiar to those skilled in the art, but I do not desire to be
restricted to this particular mechanism in the construction of the bicycle.
The power of the rider is applied to the pedals to rotate the crank arms and
the crank shaft, and the motion of the shaft is transmitted through the gearing
to the rear wheel, thus propelling the machine. As is usual in the art when
one crank is on the upstroke the other crank is on the downstroke. As one
crank moves forwardly and downwardly under the effort of the rider, the lever
attached to said crank is drawn in a forward direction to travel with the crank,
and this lever slides between its fulcrum rolls at the same time that it is rocked
or turned in pursuing the course described by its connection with the crank.
When one crank reaches the limit of its downward movement, the other crank
is brought into position for the rider to apply pressure to the other lever, and thus
the cranks present the levers and their pedals in position for the rider to advan-
tageously apply power to the levers for the continued propulsion of the machine,
said levers reciprocating in opposite directions alternately in unison with the
travel of the cranks.
The employment of long levers with pedals at their ends and each fulcrumed
at its rear end to shift or slide as the pedals travel in their orbits supplements
the leverance obtained by the cranks on the shaft, and the gear being thus
increased by the mutiplication of the leverance the machine may be propelled
at high speed by the efforts of the rider.
Changes may be made in the form of some of the parts while their essential
features are retained and the spirit of the invention embodied. Hence I do not
desire to be limited to the precise form of all the parts as shown, reserving the
right to vary therefrom.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is: —
1. In a bicycle, a frame having its horizontal rear fork extended beyond the
rear-wheel hub, the rear fork, and an arched hanger bar united firmly to the
rear fork and having its rear end forked, said forked end of the hanger bar
having its members extending across and united firmly to the extended rear ends
of the horizontal fork, combined with pairs of rolls journaled on the branches
of said forked end of the hanger-bar, levers each slidably confined between a
pair of the rolls, and a driving crank shaft connected to the levers, substantially
as described.
2. In a bicycle, an arched hanger-bar provided with the bifurcated rear end
which is united firmly to a horizontal rear fork of the frame, the transverse hori-
zontal arbors which extend through the forked end of the hanger bar and
arranged in the same vertical plane, and the two pairs of grooved rollers mounted
on the respective ends of the arbors and sustained in spaced relation one to the
other, combined with propelling levers each slidably confined between one pair
of said grooved rollers, a crank shaft geared to the rear wheel hub, and cranks
mounted on said shaft and pivoted to the levers, substantially as described.
3. In a bicycle, the combination with a wheel frame having a crank bearing,
of the levers each offset at a point intermediate of its length, and provided, in
front of its offset portion, with an internal race-way, a driving crank shaft having
the wrist pins fitted to ball bearings confined in said race-ways of the levers,
pedals attached to the front ends of the levers, the pairs of spaced bearing rolls

page_text: supported on the frame in rear of the wheel hub and each pair of rolls slidably
receiving the rear end of one lever, and gearing between the crank shaft and a
rear wheel hub, substantially as described.
Dated this 17th day of Thalame
1900
For the Applicant,
J. G. LORRAIN, M.L.E.E., M.I.Mech. E.,
Norfolk House, Norfolk Street, London, W.C.,
Chartered Patent Agent.