Improvements in the Pedal Cranks of Velocipedes.
Year: 1891

page_text: Date of Application, 14th Aug., 1891
Complete Specification Left. 21st Apr., 1892-Accepted, 21st May, 1892
PROVISIONAL SPECIFICATION.
Improvements in the Pedal Cranks of Velocipedes.
We, WILLIAM PARFREY of 36 Richardson Street, Cycle Maker, and
WILLIAM DRURY of 13 William Street, Cutler both in Swansea, in the County
of Glamorganshire do hereby declare the nature of this invention to be as
follows
-
Our invention relates to improvements in the pedal cranks of bicycles, tricycles
and velocipedes generally, the object of which is, that, by the particular
construction of said cranks according to our invention, a greater amount of leverage,
or power is brought to bear upon the driving spindle in manipulating the travel of
the machine, than obtains with the form of cranks hitherto adopted.
Our invention consists of, Firstly the manner of forming said pedal cranks, and
Secondly the manner of attaching and detaching them to, and from the driving
spindle, whether said spindle be upon the bottom bracket of the frame of the
machine, or operating the driving track wheel, or wheels direct.
In carrying our invention into effect we construct of any suitable metal or
material solid or otherwise a pedal crank, curved or bent at right angles to the
driving spindle in the direction of the rotation thereof, said curve, or bend being
carried out to any extent not exceeding 45°. The outward end of said crank may
be formed with a slot for carrying the pedal in the usual way, the inner, or spindle
end may be arranged to fit upon any form of spindle, with, or without a key and
keyway, and is formed with projecting jaws or lugs bored and tapped to receive a
set screw, or bored plain to receive a bolt and nut, the screwing or bolting together
of said jaws retains the crank upon the driving spindle. The said crank by this
means is capable of being placed upon the driving spindle, with the curve, or bend
thereof, pointing either in the same, or opposite direction to that of the rotation of
the spindle, and we are thereby enabled to provide, at will, either a forward, or
backward throw from the axis of the driving spindle, whichever may be desired, or
most suitable for the machine upon which said crank may be employed.
Or we may construct supplementary curves, or bends, capable of being attached
to ordinary straight cranks, for the purpose of providing a forward, or backward
throw, or leverage thereto, or we may attach to said cranks supplementary pieces
that are not bent, or curved, so that a right angled throw may be given to the
crank either in a forward or backward direction, said supplementary pieces, whether
curved or straight would be provided at one end with a threaded projection, that
would engage with the crank at the point, or slot provided for the reception of the
pedal and held in position by a nut screwed thereon and at the opposite end
provision would be made for attaching the pedal thereto, in a similar manner to
that by which it would have been attached to the crank. By this means we are
enabled to convert straight cranks, into curved, or right angled forward or back-
ward throw cranks at will, and adaptable for any type of machine.

page_text: .COMPLETE. SPECIFICATION.
Improvements in the Pedal Cranks of Velocipedes.
We, WILLIAM PARFREY of 36 Richardson Street, and WILLIAM DRURY, of
13 William Street, both in Swansea, in the County of Glamorgan, Cycle Maker
and Cutler. respectively 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 :-
Our invention relates to improvements in the pedal cranks of bicycles, tricycles
and velocipedes generally the object of which is that, by the particular construction
thereof in the manner constituting our invention a greater amount of leverage or
power is brought to bear upon the driving spindle by the rider or riders, in
manipulating the travel of the machine than obtains with the form or forms of
cranks hitherto adopted.
Our invention consists, Firstly of the manner of constructing the said pedal cranks
so that a forward throw or lead is given thereby in the propulsion of the machine as
an incentive for overcoming dead points or centres, and, Secondly of the manner
of attaching and detaching the said cranks, to and from the driving spindle,
irrespective of whether the said spindle be upon the bottom. bracket of the frame of
the machine, or operating the driving track wheel or wheels direct.
: In order that our invention and the manner of carrying the same. into effect may
be fully understood we have appended hereunto a sheet of drawings, in which
Fig. 1 is a side elevation of a curved pedal crank according to our invention
accompanied by a central cross section of the stem of same.
Fig. 2 is a like view shewing an alternative design in the construction of same,
this view being also accompanied by a central cross sectional view of the stem
thereof.
Fig. 3 is a view illustrating a further modification in the design of said crank.
Figs. 4 and 5 are respectively a curved and straight supplementary attachment
or extensions for converting straight cranks into throw cranks in the manner
hereinafter explained.
+
Fig. 6 is a view of the lower or axle end of Fig. 1, illustrating the application of
a screw bolt and nut, in lieu of a set screw as in Fig. 1, for drawing the jaws
together when fixing the said crank upon the pedal spindle.
Fig. 7 is a like view, partly in section, relating to Fig. 2.
Fig. 8 is a view illustrating the manner of attaching Figs. 3 and 4 to the ordinary
straight crank in general use, for converting the same into a throw crank similar in
its effect to that of Figs. 1, 2 and 3.
In carrying out our invention we cast, press, swage or otherwise construct of any
suitable metal, a velocipede pedal crank A, which, in so far as regards the stem or
shank thereof, may be either solid or hollow, and of any desired shape or
configuration in cross section, but preferably, partaking more or less of the shape
shewn by the cross sectional views in Figs. 1 and 2. The head or upper end B of
said crank may be of any suitable shape, and provided with a square, oblong,
circular or polygonal shaped hole C, for the reception of the pedal in the usual
way. The heel or lower end of said crank, usually called the boss, is so formed
that, by the means of a split a, and a preferably circular eye or opening D, a pair
of jaws b, c are formed thereon. The eye or opening D would be of such an
universal size as to be capable of being fitted firmly upon any size of pedal axle in
general use, when the jaws b. c are brought more or less closely together, which
may be carried into effect either by the means of a set screw E, passing freely
through a hole provided in the jaw c, and screwing into a hole in the jaw bas in
Fig. 1, or by that of a screw bolt E, passing freely through b and c and receiving.a
nut F, screwed thereon, as at Fig. 6. A suitable key, d may be connected to, or
formed upon any part of the metal forming the periphery of D, as in Figs. 1. 2. 3

page_text: and 7, for engaging with a similar shaped keyway or keyways upon the pedal crank
axle, or a keyway or keyways e may be provided in lieu of d as at Fig. 6, for the
reception of a key formed upon or connected to the said axle, or for the reception'
of part of a key or screw common to both, in the usual way..
As previously mentioned the object of our invention is to provide a greater
leverage or power in manipulating the travel of the machine, and to overcome or
destroy the presence of dead centres, as obtains when straight cranks are employed,
and we attain this by bending or curving the stem or shank of the crank A
transversely with the bore of the eye D, or in other words, transversely with the
pedal spindle, when this is placed in D. The said curve or bend may be either
towards the jaws b, c or in the opposite direction, and may be carried out to any
extent not exceeding 45°, but preferably not exceeding that shewn by Figs. 1
and 2, or the dotted outline thereof in the same figures. Or A may be bent or
curved as at Fig. 3 for the same purpose, the object being that the pedal eye C,
may be more or less at right angles with the eye D. By this means we are enabled
to fix the said crank upon the driving or pedal spindle with the curve or bend
either in the direction of the rotation of the spindle, or opposite thereto, according
to the particular construction of the machine, but for machines propelled by a
forward motion of the pedals said curve or bend would be in the direction of the
travel of the machine.
A forward throw or lead is thus provided which enables the rider or riders to be
always able to exert a downward pressure upon the right or left hand crank for the
propulsion of the machine, at any point of the rotation of the pedal spindle, so that
dead points or centres do not exist.
In order that a forward throw or lead may be obtained with the straight crank in
general use, such as G in Fig. 8, we provide supplementary pieces H for attaching
thereto, which may be either curved as at Fig. 4, or straight as at Fig. 5. each of
which is provided with a projection capable of fitting into the eye C, of the
straight crank G, and upon is formed a threaded projection g, so that when is
placed in C, a nut may be screwed upon g to retain H in position upon G. The
projection upon H in Fig. 4 is placed lengthwise, so that the junction of this
and G would provide a forward throw or lead, having a curve about equal to that
of the curved cranks Fig. 1 and 2, but a perfectly right angled throw or lead would
be attained by the junction of Fig. 5 and G, as shewn at Fig. 8, the projection fin
this case being placed crosswise upon H for this purpose. A suitable eye. C' would
be provided in each piece H for the reception of the pedals in the usual way. By
this means we are enabled to adapt the principle of our invention to the straight
cranks in general use at a very slight addition to the cost of the machine.
We have previously mentioned in our Provisional Specification that our said
cranks may be arranged to fit upon any form of spindle, and in order to adapt them
for use upon such spindles as are provided with a slot or annular groove for the
reception of a set screw, passing through the boss of, the ordinary crank thereinto,
for preventing the spontaneous displacement or removal of the pedal crank during
use, we arrange the holes in the jaws b. c in such a manner, that the set screw or
bolt E, when placed therein may protrude sufficiently into the eye D, as in Fig. 2,
to engage with the groove or slot m in the axle J, in lieu of the set screw previously
mentioned, and indicated by the dotted outline n, in the view Fig. 7. In this
method also the eye D may be provided with a key and keyway or keys and key-
ways in either of the mauners previously described, and for such axles as have, or
may have, square, polygonal or other shaped ends in cross section for the reception
of the cranks, we should arrange the eye D to correspond thereto in order that it
may fit thereon.
We
may in certain cases with a view to further securing the crank upon the axle,
and to improve the grip therebetween, make use of cylindrical washers p, of any
soft metal, or other suitable substance, placed within D as at Fig. 3, which may be
provided with a slit or opening s for the free passage of the loose or fixed key or
screw d previously described, or the said washer may be in- two pieces, so 88

page_text: accommodate the presence of two such keys or screws if needed. Or we may when
convenient or desirable make use of said single split washer without using a key or
keys d, and keyways therefor, the compression of p by the closing of the jaws c. b
providing sufficient grip between the crank and the axle to permit this.
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
1st. For improvements in the pedal cranks of velocipedes, the several methods of
constructing and using same herein described, or any combination thereof, connected
to, and operating in combination with, any form of pedal axle, upon any type of
velocipede; substantially as herein set forth and shewn by the accompanying
drawings.
2nd. For improvements in the pedal cranks of velocipedes, the construction and
use of a solid or hollow crank A, of any suitable shape in cross section, bent or
curved in any direction and to any angle, during the casting, pressing, swaging or
otherwise construction thereof, provided at its upper end with any shaped head B.
with any form of pedal aperture C, its lower end being provided with a boss, having
jaws b. c, at right angles with either side of the stem or shank of A, with circular or
other shaped aperture or eye D, for the reception of the pedal spindle, provision
being made in any part thereof for the use of a key or keys d, or keyway or
keyways e. The manner of attaching and fixing said crank to and upon the pedal
spindle, by the means of a set screw E, passing freely through e and screwing into,
or passing freely through b and c and receiving a nut, F, for closing or partly closing
the said jaws, thereby contracting the area of the aperture D, substantially as
herein described and shewn by Figs. 1. 2. 3 and 6 of the accompanying drawings.
3rd. In combination with the improved pedal crank as set forth in the preceding
claim, the manner of arranging the set screw or bolt E, so as to engage with the
usual slot or groove m, formed upon the spindle J, in lieu of the usual set screw n,
for preventing the spontaneous displacement or removal of said crank from the
pedal spindle when in use, substantially as herein described and shewn Figs. 2 and 7.
of the appended drawings.
;
4th. In combination with any form of straight crank G, the construction and use
of straight or curved supplementary extension pieces H, provided with a
projection, screw g, and pedal aperture C³, connected to the pedal aperture C of G,
by the means of a nut screwed upon g when f is inserted within C, for converting
the said straight crank into a curved or rectangular throw crank, similar in action
to Figs. 1 and 2, substantially as and for the purposes herein set forth, and shewn
by Figs. 4. 5 and 8 of the drawings hereunto annexed.
Dated this 21st day of Anvil 1900
GEO. THOS. HYDE,
4, Moorfields, Fore Street, London, E.C., Agent for the Applicants.