Improvements in or connected with the Cranks and Pedals of Cycles.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in or connected with the Cranks and Pedals of Cycles.
We, WILLIAM HAYNES, of Darwen Street, Weaste, Salford, in the County of
Lancaster, Mechanical Engineer, and PERCY WITHECOMB of Ducie Grove,
Manchester, in the County of Lancaster, aforesaid, Tobacconist, do hereby declare
the nature of this invention to be as follows:-
The invention is designed to obtain a longer throw or reach of the crank or pedal
on the down stroke than on the up stroke and so increase the power of driving
and allow of larger driving wheels to be employed.
It comprises an eccentric attachment between the crank and the pedal whereby
the pedal is carried further away from the crank centre or axle on the down stroke
and brought back towards it on the up stroke of the revolution.
A disc is inserted in a socket in the end of the crank and is capable of rotating
in bearings about its own axis as the crank rotates. The pedal is mounted on a
stud or otherwise eccentric to this disc. Any suitable form of bearing may be
employed.
A catch snug pawl or the like may be suitably placed to lock the crank and
pedal together at any point of the revolution either automatically or otherwise as
may be required.
Dated this 10th day of December 1896
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with the Cranks and Pedals of Cycles.
We, WILLIAM HAYNES, of Darwen Street, Weaste, Salford, in the County of
Lancaster, Mechanical Engineer, and PERCY WITHECOMB, of Ducie Grove,
Manchester, in the County of Lancaster, Tobacconist, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement:-
This invention relates to an improved form of crank and is designed to obtain
a longer throw or reach of the crank from the crank axle on the down strok: than
on the up stroke or in other words to obtain a greater or longer leverage effective
for driving without enlarging the circle or path which the operating foot or pedal
traverses.
It consists essentially in constructing the crank with an eccentric attachment

page_text: between the crunk and the pedal whereby at each revolution the pedal is carried
further away from the crank centre or axle on the down stroke and brought back
towards it on the up stroke of the revolution.
It will be fully described with reference to the accompanying drawings.
Fig. 1. Side elevation of crank constructed according to the invention showing
the relative position of crank and pedal on the downward stroke.
Fig. 2. Sectional elevation of same.
Fig. 3. Plan.
Fig. 4. Side elevation showing the invention applied, to an ordinary crank.
Fig. 5. Plans of same.
Fig. 6. Diagrams showing the relative positions of the crank and pedal at
different points of the revolution of the crank.
The crank A is constructed with an annular socket a at the free or pedal end.
In this socket is fitted a disc or wheel 33 capable of rotating therein about its own
axis. The pedal C is fitted or attached to a pin D so as not to rotate thereon and
the pin D is firmly fixed to the disc B at some distance from its centre so that it
is eccentric thereto. Any suitable form of bearings may be provided for the
dise B at present we prefer to employ halls inserted between two dises as shown or
arranged in any other convenient manner.
Referring to Figs. 4 and 5 the invention is shown as applied to an ordinary
crank, the disc B is provided with a stnd or pin & which is screwed into or other
wise firmly attached to the end of the ordinary crank and around this disc is fitted a
strap or hoop E capable of rotating around the disc 131 preferably provided with
hall hearings. The pedal is screwed into the hole in the lug e or otherwise firmly
attached to the rotating strap E which thus places it eccentric to the disc B'.
The disc B may be locked to the crank A to prevent rotation of the former by
means of a catch snug or pawl suitably placed such as by a bolt or catch placed
longitudinally of the crank to engage with pins or notches in the back of the
eccentric or a bolt or catch fitted to the pedal to engage with notches or holes in
the face of the annular end a of the crank A.
When in operation the action of the foot of the rider maintains the pedal C
horizontal or approximately horizontal (varying only with the movement or
inclination of the foot) and thus causes the pedal always to remain in advance of
the central axis of the disc B a rotary movement taking place between the dise B
and the annular socket or end a of the crank. It will thus be seen that on. the
down stroke the nedal C reaches to the extremity of the crank A whereas on the
up stroke the pedal is much nearer to the crank centre or axle F. By this means
a greater leverage is obtained on the down or effective stroke without increasing
the circle through which the foot travels or the distance the foot rises and falls
thus giving the rider all the advantages of a longer crank without the incon-
venience that would attach thereto. The dotted circle - Fig. 6 shows the
circle or path through which the pedal travels while the dotted circle y-y shows
the path of the central axis of the dise B and also corresponds with the path of a
pedal attached to an ordinary crank with a throw equal to the distance of the
centre of A to the centre of F. These two circles are equal in diameter and cir-
cumference. The dotted circles zz indicate the position of the chain wheel.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is.--
1. A crank for cycles constructed with an eccentric connection or attachment
between the free end of the crank and the pedal whereby the pedal is carried
further away from the crank centre at one part of the stroke than another.
2. A crank for cycles constructed with an annular socket at the free end in
combination with a disc or wheel capable of rotating therein and a pedal attached
eccentrically thereto substantially as and for the purpose described.
3. The combination with a crank for cycles of a disc secured or attached to the

page_text: cnd thereof and a strap or hoop to which the pedal is eccentrically affixed capable of
rotating round the disc substantially as and for the purpose described.
4. The improved construction and arrangement of cranks and pedals for cycles
substantially as described and shown with reference either to Figs. 1 to 3 or Figs. 4
and 5 of the drawings.
Dated this 2nd dow of Contember 1007
WM. P. THOMPSON & Co., .
Manchester, Liverpool & London, Patent Agents.