Year: 1897

page_text: Date of Application, 8th Mar., 1897-Accepted, 10th Apr., 1897
We, THOMAS HARRY BELCH, Mechanic, and GEORGE REGINALD GRAY,
Lumberman, both of Main Street, in the Village of Coldwater, in the County of
Simcoe, and Province of Ontario, Canada, 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 invention is to provide a cycle driving-gear which will afford
increased leverage during the position of the pedal crank when leverage is most
effective, and will thus permit of the machine being highly geared up for speeding
purposes without causing undue strain to the rider; and it consists, essentially, in
supporting from the crank-axle bracket, and to the front thereof so that it may be
eccentric to the crank axle, a circular bearing adapted to carry a supplemental
pedal crank, a suitable guide-way being formed therein, so that it may slide to and
fro on the end of the crank as the supplemental crank which carries the pedal
moves around its eccentric circular bearing; and thus the pedal, while moving in
a circle concentric with the eccentric circular bearing, keeps approaching or
receding from the crank-axle and thus varies the leverage as hereinafter
specifically described.
Figure 1, is a perspective view of a bicycle showing the driving gear in position,
and the means for holding the eccentric circular bearing in place outside of the
sprocket-wheel.
Figure 2, is a detail showing the driving-gear in place on that end of the crank
axle which is away from the sprocket wheel, with the pedal crank at its greatest
leverage.
Figure 3, is a detail showing the driving gear moved round from the position.
shown in Fig. 2, and showing only a medium leverage.
Figure 4, is a sectional detail showing the mode of connecting the end of the
crank to the slide in the supplemental crank.
Figure 5, is a cross-section on line a'-', Fig. 3, through the eccentric circular
bearing.
Figure 6, is a detail showing the mode of connecting the eccentric circular
bearing to the crank-axle bracket.
In the drawing, like letters of reference indicate corresponding parts in the
different figures.
In Fig. 1, which shows the device in position on a bicycle, with the right pedal
at its extreme forward throw and greatest leverage, while the left pedal is hidden
from view-A, are the eccentric circular bearings shown on either end of the crank
axle. The eccentric circular bearing A, which appears on the right side of the
bicycle, is held in operative position by the loop connections B, B', B", connecting
this circular bearing to the crank axle bracket. These connections B, B', B", are
preferably shaped as indicated so as to bridge over the sprocket wheel C, and
afford a space through which the sprocket teeth carrying the chain may freely
move. As in other respects, the driving gear has similar parts on both sides of the
bicycle, it will only be necessary hereinafter to refer to the parts shown in the
enlarged details in the remaining figures.
In Figs. 2, and 3, which show the gearing on the left hand side of the bicycle

page_text: opposite to that indicated in Fig. 1,-C, is the sprocket wheel shown on the far
side of the crank axle, and B, B¹, B", are the loop connections on the far side of
the circular bearing already referred to under Fig. 1. D, is one of the chain
stays. A, is the eccentric circular bearing grooved to form a race-way for balls a,
as seen in Fig. 5. E, is the crank axle bracket to which the circular bearing A, is
secured by means of the braces F, F', shown in Figs. 2 and 3, while the short
brace F, which in hidden from view in these figures, is indicated in Fig. 6.
Although we have shown this method of holding the circular bearing A, in
operative position in front of and eccentric to the crank-axle, any other method
which would hold it in such operative position would be within the scope of the
invention.
G, is the crank of ordinary length which is connected to the crank-axle H, in
the usual manner. I, is the supplemental pedal crank which is provided at its
inner end with the ring I', which is grooved at i, as indicated in Fig. 5, so as to
enclose a race-way for the balls a, already referred to. This ring 1', is split and
flanged at 1", as shown in Fig. 2, its flanges being bolted together so as to hold
the parts in place that the ring may be free to rotate on the eccentric circular
bearing A. We have thus indicated a preferable way of holding the supplemental
crank I, in operative position on the eccentric circular bearing A, but any other
method which would permit of the free rotation of the supplemental pedal crank,
which carries the pedal J, so that the pedal J, may move round in a circle,
concentric with the circular bearing A, would suffice and be within the scope of the
invention.
K, is a slide formed in the supplemental pedal crank I, at the outer end thereof,
and which is made of sufficient length to allow of the maximum and minimum
throw of the pedal. This slide K, is shown in cross section in Fig. 4, and engaging
therewith is shown the slide block L, which is pivotally connected to the outer end
of the crank G, and is held in operative position as indicated in dotted lines in
Fig. 2. Although we have shown this method of connecting the end of the crank
with the supplemental pedal crank 1, it may be so connected therewith as to have ball
bearings, or some other device may be employed to permit of the free movement of
the supplemental pedal crank to and fro on the end of the pedal crank G, and at
the same time exclude the dust from the bearings.
In Fig. 3, is shown the gearing after the pedal has performed a quarter of a
revolution, and it is in that position which affords only a medium leverage as
compared with that indicated in Fig. 2.
When the crank G, continues its circular motion and the pedal is in proximity
to the chain stay D, the gear is in a position when the least leverage is afforded,
and it will thus be seen that as the pedal completes its circle, the leverage is
continuously increasing or decreasing according to the position in which the foot
may be while operating the machine, the greatest leverage being afforded when the
pedal is in the position indicated in Fig. 2. It is thus obvious that while the foot
of the rider only moves in a circle, of which the centre is at the centre of the
circular bearing A, that the foot is continuously increasing or decreasing its
distance from the crank-axle H, and thus increased or diminished leverage is being
continuously applied as motive power.
It may be mentioned that the supplemental pedal crank may be of such width at
its inner end near the ring, that at any position of the crank during its rotation,
space may not be left between the supplemental pedal crank and the crank G, in
which any portion of the dress of the rider might become caught.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In a cycle driving gear, the combination of a bearing suitably held in position
eccentric to the crank-axle; a supplemental pedal crank adapted to move on the
eccentric bearing: a crank connected to the crank-axle: and means for slidingly

page_text: connecting the supplemental pedal-crank to the outer end of the crank, substantially
as described and for the purpose specified.
2. In a eyele driving gear, the combination of a circular-bearing suitably held in
operative position forward of the crank-axle and eccentric thereto; a supplemental
pedal crank adapted to move on the circular bearing so that the pedal may describe
a circle concentric with the eccentric circular bearing; a crank connected to the
crank axle; and means for slidingly connecting the supplemental pelal-crank to
the outer end of the crank, substantially as and for the purpose specified.
3. In a cycle driving gear, the combination of a circular bearing; braces
connecting the circular bearing to the crank-axle bracket in such a manner that
it may be held in operative position forward of the crank-axle and eccentric
thereto; a supplemental pedal crank provided with a ring adapted to engage with
and move over the circular bearing; a crank connected to the crank-axle; mean
for slidingly connecting the supplemental pedal-crank to the outer end of the
crank; and a chain sprocket wheel attached to the axle, substantially as and for
the purpose specified.
4. In a cycle driving gear, the combination of a circular bearing; braces.
connecting the circular bearing to the crank axle bracket in such a manner that
it may he held in operative position forward of the crank axle, and eccentric
thereto; a supplemental pedal-crank provided at its outer end with a slide and at its
inner end with a ring adapted to engage with and move over the circular bearing;
a crank connected to the crank-axle; a slide-block fitted within the slide and
pivotally connected to the outer end of the crank, substantially as and for the
purpose specified.
5. In a cycle driving gear, the combination with the eccentric circular bearing A.;
of the looped connections B, B, B", bridging the sprocket wheel C; and the
crank axle bracket E, substantially as described and specified.
6. In a cycle driving gear, the combination with the eccentric circular bearing A,
suitably grooved and held in position forward of the crank axle H; of the
supplemental pedal crank I, provided with ring 1', grooved at i, so as to form,
when in operative position on the circular hearing A, a race-way for the balls a,
substantially as and for the purpose specified.
7. In a cycle driving gear, the combination with the eccentric circular bearing A,
suitably grooved and held in operative position forward of the crank-axle H; of
the supplemental pedal-crank I, provided with ring I', split and flanged at Ill to
receive a bolt and grooved at i, forming with the grooved circular bearing A, &
race-way for the balls a, the pedal J; the slide K, formed at the outer end of the
supplemental pedal-crank I; the crank axle H, journalled in the crank-axle
bracket E; the crank G; and the slide-block L, pivotally connected to the outer
end of the crank G, and engaging with tho slide K; and the chain sprocket
wheel C, fixed to the crank axle H, substantially as specified.
BOULT & WADE,
Agents for the Applicants..