Year: 1896

page_text: Date of Application, 25th Aor.. 1896
Complete Specification Left, 25th Feb., 1897-Accepted, 10th Apr., 1897
We, JAMES COCKBURN, of 631 Alexandra Parade, in the City of Glasgow,
Engineer, WILLIAM HENRI LUTHER, of Belmont, Helensburgh, in the County of
Dumbarton, Iron Merchant, and JOHN MILLAR, of 79 McLaughlin's Terrace,
Dalmuir, in the County of Dumbarton, Engineer, do hereby declare the nature of
this invention to be as follows:-
This invention has for its object to obtain greatly increased power or leverage in
propelling cycles by simplifying and improving the arrangement and construction
of the driving gear.
Under the invention the usual driving cranks are dispensed with and are replaced
by treadle levers pivoted one on each side of the cycle frame and counccted through
links or connecting rods to cranks either on the axle of the driving wheel or on
spindles geared to the hub of such wheel.
The treadle levers are each made in the form of a bell crank having a driving
podal on the horizontal armı whilst the vertical arm has jointed to it one end of a
link or connecting rod whose other end embraces the pin of the crank which turns
the driving wheel, the crank being centred on the cycle frame or fork and having
on its spindle a toothed or friction wheel gearing with a similar pinion on the
driving wheel hub or being furnished with a chain wheel. The cranks are disposed
in line opposite each other so that when one treadle is at its lowest position or at
the end of the stroke the other is near its highest position or upper end of the
stroke, and the links or connecting rods and crank arms are of such length that
when one crank is on the dead centre the other is over it; so that in ordinary
working conditions there is practically no dead centre.
In cases in which the length of stroke of the treadles may be regarded as
excessive means are or may be provided for raising or partially raising the pedal ae
the treadle nears the lower end of its stroke. For this purpose the pedal may be
fitted on a crank controlled by a link having on it a pin working in a cam groove
on the side of the treadle or the pedal may be supported by a spring which will
yield whilst the full pressure of the foot is applied to the pedal in the earlier part
of the stroke but which will raise the pedal as the foot pressure becomes weaker
near the end of the stroke.
We, JAMES COOKBURN, of 631 Alexandra Parade, in the City of Glasgow,
Engineer, WILLIAM HENRI LUTHER, of Belmont, Helensburgh, in the County of
Dumbarton, Iron Merchant, and JOHN MILLAR, of 79 McLaughlin's Terrace,
Dalmuir, in the County of Dumbarton, Engineer, do hereby declare the nature of

page_text: 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 has for its object to obtain greatly increased power or leverage in
propelling cycles by simplifying and improving the arrangement and construction
of the driving gear.
Under the invention the usual cranks are dispensed with and are replaced by
treadle levers pivoted one on each side of the cycle frame and connected through
links or connecting rods to cranks either on the axle of the driving wheel or on
spindles geared to the hub of such wheel.
The invention is illustrated by the accompanying drawings, Fig. 1 being au
elevation of the driving gear, and Figs. 2 and 3 like views of modified forms of
the same.
The treadle levers A are each made in the form of a bell crank having a driving
pedal B on the horizontal arm whilst the vertical arm has jointed to it one end of a
link or connecting rod C whose other end embraces the pin of a crank D which
turns the driving wheel E the crank D being centred on the cycle frame or fork F
and having on its spindle a friction wheel or toothed wheel G gearing with a similar
pinion H on the driving wheel hub 1 or being furnished with a chain wheel. The
cranks D are disposed in line opposite each other so that when one treadle is at its
lowest position or at the end of the stroke the other is near its highest position or
upper end of the stroke, and the links or connecting rods C and crank arins D are
of such length that when one crank is on the dead centre the other is over it; so
that in ordinary working conditions there is practically no dead centre.
In cases in which the length of stroke of the treadles may be regarded as
excessive means such as illustrated by Figs. 2 and 3 are or may bo provided for
raising or partially raising the pedal B as the trendle A nears the lower end of its
stroke. For this purpose the treadle B may be fitted as shown at Fig. 2 on a
crank J centred on the end of the treadle A and controlled by a slotted link K
centred at Lou a bracket N secured to the treadle bearing at the side of the
treadle A, said link having a pin L working in a cam groove M in the bracket N,
the object being to present the treadle to the foot at the beginning of the stroke
somewhat lower, and at the end of the stroke somewhat higher than when the
pedal is carried directly on the end of the trendle lever, thus shortening the length
of tread. As an alternative the pedal B may be fitted on one end of a double ended
lever O the other end of this lever having the controlling link K attached to it, as
shewn at Fig. 3.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The improved driving gear for cycles consisting of bell crank treadle levers
and links actuating cranks on the driving wheel hub or on a spindle geared to the
wheel hub, the cranks being set diametrically opposite each other so as to avoid the
forming of dead centres substantially as described.
2. ln driving gear for cycles the improved means for raising the pedals at the
end of the stroke consisting of a link travelling in a cam groove and controlling the
crank on which the pedal is pivoted substantially as described.
Dated this 24th day of February 1897.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
32 St. Vincent Street, Glasgow, Agent for the Applicants.