An Improved Method of Constructing the Driving Gear of Velocipedes.
Year: 1891

page_text: Date of Application, 19th Mar., 1891
Complete Specification Left, 1st Dec., 1891-Accepted, 2nd Jan., 1892
PROVISIONAL SPECIFICATION.
An Improved Method of Constructing the Driving Gear of
Velocipedes.
WILLIAM ANDREWS of 39 Trinity Road, Aston, Birmingham in the County
of Warwick, Machinist, do hereby declare the nature of this invention to be as
follows:-
My invention relates to a novel construction of crank, and also to connecting the
crank and gear wheel to the driving axle of velocipedes.
By the term "crank " I mean the single lever, which is usually provided_with
enlargements at each end, one of which is fitted on to the axle or shaft, and the
other provided with a crank pin.
Cranks for velocipedes, as heretofore constructed, consist of such a single lever
provided with a boss which is bored out to fit onto the axle, while the other end is
usually provided with an elongated hole or slot adapted to receive the crank pin,
which crank pin is generally provided with pedals. In constructing a crank
according to this my invention I form the lever of a single piece of metal of any
desired section and devoid of bosses or enlargements. The length of this lever is
made to suit the radius described by the crank pin. The axle boss is made of a
separate piece of metal provided with apertures or passages at right angles to each
other. One of the apertures admits the axle, and the other is adapted to receive one
end of the said lever. The crank pin boss is made of a similar separate piece of
metal with apertures at right angles to each other, one aperture is formed to
receive the end of the crank pin and the other admits the outer end of the crank
lever. The apertures or passages in the aforesaid separate bosses slightly intersect
each other so that the aforesaid lever in passing through its apertures, intersect
the axle at one end and the crank pin at the other.
A portion of the axle or crank pin is shaped to allow of the lever passing or
sliding upon the crank pin or axle respectively. The bosses are secured at any
desired position on the lever by set screws, taper pins, bolts, wedges or other well
known equivalent devices.
In some cases I form the crank by bending one end of the lever at right
angles to its length, the other end of the lever is then provided with a separate
boss adapted to engage with the axle as before described. The said bosses
may be of any desirable shape. In some cases I form them of solid blocks of
metal with apertures intersecting at right angles and drilled or shaped to suit
the section of the lever and axle. In other cases I form them of split blocks,
or flat bands of metal bent up into shape, but in every case my improved crank
consists of a lever with one or more separate bosses by means of which I build up
a complete crank, and attach it to its axle.
I will now describe my improved method of connecting the drive gear to the
crank and axle of a velocipede. According to this my invention I do not fix the
drive gear directly to the axle, but instead thereof I make it a good sliding fit
upon the said axle. In order to cause the said gear to partake of the revolution
of the crank and axle I connect the gear to the boss of the crank by causing part
of the gear to engage with part of the crank boss, or the gear and the crank inay
be separably connected by steady pins or screws. The aforesaid crank being now
firmly fixed to the axle, and the gear being connected to the crank as described,
both the crank and the gear are adapted to receive and communicate power
imparted to them. It will be seen that the gear can be readily removed and
replaced by simply disconnecting the crank with the usual tools carried by cyclists.
Although I have described this method of fixing drive gears in connection with my

page_text: built-up crank it is evident that the same method is applicable to cranks of
ordinary construction.
Dated this 18th day of March 1891
COMPLETE SPECIFICATION.
An Improved Method of Constructing the Driving Gear of
Velocipedes.
WILLIAM ANDREWS of 184 Trinity Road, Aston juxta Birmingham, in the
County of Warwickshire, Engineer, 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 :-
My invention, relates to a novel construction of crank, and means of connecting
the crank, and gear wheel, upon the driving axle of velocipedes. By the term
66 crank,"
"I mean the single lever, which is usually provided with enlargements, at
cach end, one of which, is fitted on to the axle, or shaft, and the other provided
with a crank pin. Cranks for velocipedes, as heretofore constructed, consist of
such a single lever, provided with a boss, which is bored out to fit on the axle,
while the other end, is usually provided with an elongated hole, or slot, adapted to
receive the crank pin, or pedal pin; which crank pin, or pedal pin, in the case of a
velocipede, is generally provided with pedal treads. In constructing a crank,
according to this my invention, I form the lever of a single piece of metal, of any
desired section, and of a length to suit the radius, to be described by the crank pin,
or pedal pin.
The axle boss is mode of a separate piece of metal, provided with apertures, or
passages, at right angles to each other, one of these apertures admits the axle, and
the other is adapted to receive one end of the aforesaid lever.
The crank pin, or pedal pin boss, is made of a similar separate piece of metal,
with apertures at right angles, one aperture admits the crank pin, and the other, is
adapted to receive one end, of the aforesaid lever. The apertures, or passages,
in the aforesaid separate bosses; slightly intersect each other, so that the aforesaid
lever, in passing through its aperture, or opening, intersects the axle at one end,
and the crank pin at the other. A portion of the crank pin, or pedal pin, is shaped
to allow of the parts passing, or sliding, one upon the other.
If desirable, the bosses may be secured, at any desired position on the lever, and
axle by set screws, taper pins, wedges, or other well-known equivalent devices.
In some cases, I form the crank pin, by bending over one end of the lever, at right
angles to its length; the other end of the lever, is provided with a separate boss,
as before described. The said bosses may be of any desirable shape. In some
cases, they are formed from solid blocks of metal, with apertures intersecting, at
right angles, drilled, or shaped, to suit the section, of the axle and lever.
In other cases, they are formed of split blocks, or flat bands of metal, bent up
into shape; but in every case, my improved crank, consists of a lever, with one,
or more separate bosses, by means of which, I build up, a complete crank, and
attach it to its axle.
I will now describe, my improved method, of connecting the drive gear, to the
crank, and axle of a velocipede. The said drive gears as heretofore con-
structed, arc keyed, or firmly fixed, upon the axle, to which said axle, the crank is
also connected. According to this my invention, I do not key, or fix, the drive
gear to the axle, but instead thereof, I make it a good sliding fit, on the axle. In
order to cause the said gear, to partake of the revolution of the crank, and axle ;
I connect the gear to the boss of the crank, by causing part of the gear, to engage
with part of the crank boss. In my Provisional Specification, 1 stated that the
gear, and the crank, may be connected, by studs, pins, or screws; but I have ascer-
tained since, by experiment, that such studs, pins, or screws, if inserted in a crank

page_text: The manner in which the said invention, may be most advantageously, carried
into practice, may be readily understood, by referring to the accompanying
drawings, which I will now proceed to describe.
Fig. 3, is an elevation of the crank, and gear wheel, partly in section, and Fig. 4,
is an elevation of the same, at right angles to Fig. 3; A Fig. 3 and Fig. 4, is the
lever, forming the crank; b, b, Fig. 3, are the inclines formed on each end of the
crank, engaging with suitable surfaces, formed on the axle B, and the crank pin C;
the said inclines, are more clearly shewn at Fig. 5 and Fig. 6; d, d, are the screws
and nuts, which operate, to draw the inclines b, b, into absolute contact, with their
respective surfaces. E Fig. 3, and Fig. 4, is an axle boss, and F, a crank pin boss,
shewing the apertures, for the passage of the axle, and crank pin, at right angles
to, and intersecting each other. N Fig. 4, shews the detachable connection,
between the axle boss E, and the gear G; N, is a projection on the axle boss E,
which engages with a slot, or groove, in the boss of the gear G; if desired, the
projection, N, may be formed on the boss, of the gear G, and the groove, is then
made in the boss E.
Fig. 7, shews a modified form, of crank boss, being made in two parts, and
connected, by any well known means.
Fig. 8, shews another modification, of crank boss, consisting of a flat band of
metal, provided with two apertures, a, d; the passage, or aperture, for the axle in
this case, being formed, by bending up the flat strip, into the shape of the letter U,
as shewn in the drawing.
Fig. 9 is a modified crank, in which the crank pin, is formed by bending the
material of the crank, at right angles to itself, the remaining end, is provided with
an axle boss, as shewn in the drawings.
Fig. 10, is a crank, with an enlarged end, or eye, integral with the crank, and
Fig. 11, and Fig. 12, shew a pedal, or crank pin boss, formed integral with the
pedal pin, and secured by a taper pin, and lock nut; engaging in one of the series
of grooves, formed in the upper end of the crank, as shewn, in the drawings.
Fig. 13, is a crank, with a slotted end, integral with the crank, the opposite end,
being furnished with a separate boss, as before described.
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 :
i. In a crank for driving velocipedes, the construction of a lever, provided with
one, or more bosses, detachably connected, substantially as, and for the purpose
described.
ii. In a crank for driving velocipedes, the use of bosses, or blocks, with holes,
at right angles, and intersecting each other, so that shafts, passing through the
boles, engage with each other, substantially as, and for the purpose described.
iii. In a crank for driving velocipedes, the combination of a lever, having

page_text: inclines; with bosses, or blocks, having apertures, at right angles to each other,
substantially as described, and illustrated, by Figs. 3, 4, 5, 6, 7, 8, 9, of the accom-
panying sheet of drawings.
iv. In a crank for driving velocipedes, a lever, having an axle boss, formed
integral with the crank, as shewn in Fig, 10, in combination with a separate crank
pin boss, such crank pin boss, being of the form described, and illustrated, by
Figs. 3, and 4, or alternatively, by the forms described, and illustrated, by
Figs. 7, 8, 11, 12.
v. In a crank for driving velocipedes, a lever, having a slotted end, formed
integral with the crank, in combination, with a separate axle boss, of the form
described, and illustrated, by E, Figs. 3, and 4, or alternatively, of the form
described, & illustrated, in Figs. 7, 8.
vi. In a driving gear for velocipedes, the construction and use of a gear wheel,
sliding freely upon its axle, and provided with a groove, or tongue, adapted to
engage with, tongue, or groove, formed on a crank pin boss, fixed upon the same
axle, substantially as described, and illustrated, at N, Fig. 4, of the accompanying
sheet of drawings.
Dated this 30th day of November 1901
WILLIAM ANDREWS.