Year: 1896

page_text: Date of Application, 21st July, 1896
Complete Specification Left, 5th Apr.. 1897-Accepted, 22nd May, 1897
I, EDWIN YARRINGTON MACKENZIE of Kingston, Jamaica, W.I., Watch-
maker, do hereby declare the nature of this invention to be as follows:-
This invention relates to a crank and pedal for use with cycles and by means of
which the rider is enabled to materially increase the leverage and the effective arc
of the crank during its rotation.
The crank which may be keyed or otherwise attached in the usual way to the
sprocket wheel, is provided with a pin or stud on which the pedal revolves and is
prolonged beyond the pedal pin terminating in a quadrant or segment furnished
with any desired number of teeth. From the outer end of the pedal which is
pivoted eccentrically, projects a lug to which is pivoted a pawl of sufficient length
to engage with one or other of the teeth on the quadrant, a suitable spring being
provided upon the pedal for the purpose of retaining the pawl in position.
The pedal operates in the usual way during the upward motion of the crank
but when this latter has passed the vertical, the forward end of the pedal is
slightly raised by the flexion of the rider's ankle until the pawl engages with one
of the outer teeth of the quadrant. In this position the pedal becomes rigidly
locked to the crank arm and thus practically forms an extension of the same,
thereby materially increasing the effective length of the crank.
By the continued rotation of the crank the rider's foot gradually assumes a
horizontal position after which the further revolution of the crank causes the tooth
upon the quadrant to disengage itself from the pawl and the pedal to turn upon its
axis or pin until the pawl engages with one of the inner or back teeth of the
quadrant, the pedal being thereby secured at approximately right angles to the
crank.
If desired, I may attach a suitable metallic or other shield to the pedal for
the purpose of preventing the rider's shoe from interfering with the proper working
of the pawl and toothed quadrant.
I, EDWIN YARRINGTON MACKENZIE, of Kingston, Jamaica in the West
Iudies, Watch-maker, 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 an improved crank and pedal for use with cycles and by

page_text: means of which the rider is enabled to materially increase the leverage and the
effective arc of the crank during its rotation.
Upon the accompanying drawings illustrating my invention-
Figure 1 is a side elevation of my improved crank and pedal, the dotted lines
shewing the crank at the bottom position;
Figure 2 being a plan of the same;
Figure 3 is a side elevation of the pedal.
In carrying out my invention I adopt the arrangement hereafter described and
shewn on the drawings. The crank A which may be keyed or otherwise attached
in any suitable way to the spindle of the sprocket wheel, is provided with a pin or
stud B on which the pedal revolves and is prolonged beyond the pedal pin
terminating in a quadrant or segment C furnished with any desired number of
teeth. From the outer end of the pedal D which is pivoted eccentrically projects
a lug E to which is pivoted a pawl F of sufficient length to engage with one or
other of the teeth on the quadrant C, a suitable spring G being provided upon the
pedal D for the purpose of retaining the pawl in position; and a stop pin H
being also secured in a suitable position to prevent the paw! F from falling too far
forward. To allow the pawl and its pivot to clear the crank A in rotating, I may
either form the crank A with a set-off or provide a suitable groove or recess on its
outer surface.
The pedal D operates in the usual way during the upward motion of the crank A,
but when this latter has passed the vertical, the forward end of the pedal D is
slightly raised by the flexion of the rider's ankle until the pawl engages with one
of the outer teeth of the quadrant C. In this position the pedal D becomes rigidly
locked to the crank arm A and thus practically forms an extension of the same,
thereby materially increasing the effective length of the crank.
By the continued rotation of the crank A, the rider's foot gradually assumes a
horizontal position, after which the further revolution of the crank causes the
tooth upon the quadrant to disengage itself from the pawl F and the pedal D
to turn upon its axis or pin B until the pawl F engages with one of the inner
or back teeth of the quadrant C, the pedal D being thereby secured at
approximately right-angles to the crank A, as shewn in dotted lines in Figure 1.
Or alternatively, I may arrange to substitute for the toothed pawl and quadrant
above described, a friction gear, in which case the teeth are dispensed with, and a
wedge-shaped groove is formed at the upper and lower end of the quadrant into
which engages a spring pawl of corresponding section.
If desired, I may attach a suitable metallic or other shield d to the inner side plate
of the pedal, as shewn on Figure 3, for the purpose of preventing the rider's shoe
from interfering with the proper working of the pawl and toothed quadrant or
friction gear.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. The improved cycle crank and pedal, constructed and arranged substantially
as hereinbefore described with reference to the annexed drawings.
2. An eccentrically pivoted pedal D the larger half being provided with a
pawl F adapted to engage with the teeth of a quadrant C situated on an extension
of the crank arm A, for the purposes and substantially as described.
3. The combination of a crank arm A a pedal pin B secured between the ends
of the crank arm, said euds of the crank arm extending on opposite sides of the
pedal pin B, a pedal D eccentrically pivoted on the pedal pin, a toothed quadrant C
secured to and extending from the outer end of the crank arm A beyond the pedal
pin and having a central plain portion, and a spring pawl F pivoted on the longer
end of the pedal D and normally held in engagement with the teeth on the
quadrant C, substantially as set forth.
4. The combination of a crank arm A, a pedal pin B secured between the ends

page_text: of the crank arm, said ends of the crank arm extending on opposite sides of the
pedal pin, a pedal D eccentrically rivoted on the pedal pin, a quadrant C grooved
at its ends secured to and extend om the outer end of the crank arm beyond
the pedal pin and having its ce rt plain, and a spring pawl pivoted on the
longer end of the pedal D and. to engage in the grooves of said quadrant,
Dated this Fifth day of A.
1897.
For the Applicant,
GEDGE & FEENY,
60 Queen Victoria Street, London, E.C., Chartered Patent Agents.