Mechanism for Velocipedes.
Year: 1888

page_text: Mechanism for Velocipedes.
I, JOHN CLOUGH, of 4, Rose Bank, Manningham in the County of York, Manager
do hereby declare the nature of this invention to be as follows:-
―
This invention relates to improvements in that type of velocipedes in which a chain
is employed to communicate motion from the treadle shaft to the driving wheel, wheels
or driving axle, and its object is to provide a simple method or means of altering the
relative speed of the treadle shaft and driving wheel, or wheels; with the object of
applying greater power or speed to such wheel, or wheels as required.
I attain these objects by employing an expanding or contracting chain wheel prefer-
ably upon the treadle shaft.
The invention consists in the construction of the said chain wheel, and in the means
or method of expanding or contracting such wheel and also in the device or devices
for controlling the expansion and contraction.
For this purpose one of the chain wheels preferably that on the treadle shaft is
divided into three or more sections, each section being mounted on or in a radial
guide and provided with a projection or recess on the face adapted to engage a cam
or scroll disc loosely mounted by the side of said segments. The said cam disc has
two concentric annular guides the diameters of which bear the same proportion to each
other as the amount of expansion and contraction of which the wheel is capable, and
such guides are each provided with a stop at suitable parts and are there connected
by a short guide, thus forming a cam in the shape of an irregular spiral or scroll.
The said projections on each of the segments engage the said annular guides on the
cam disc, therefore it will be readily seen if such disc is held stationary whilst the
rotation of the treadle shaft is continued, approximately a revolution, such sections are
moved away from or towards the treadle shaft according to whether the said projec-
tions are passed into the larger or smaller circular guide, and if, when the said cam
disc is held stationary, the position of the said short connection between the two
circular guides is so arranged that immediately each section becomes free from the

page_text: chain it is passed into or on to the other guide the segments are expanded with little
friction when clear of the chain. The amount of expansion is preferably so arranged
that the segments are separated the distance the pitch of the chain when the wheel
is expanded.
I operate the cam disc in this manner by employing a catch, pivoted on a convenient
part of the velocipede, adapted to engage with a projection or its equivalent on the
said cam disc and hold it stationary when the said catch is placed in contact therewith
by the pressure of the foot or other means. And when the whole of the sections have
been expanded or contracted I automatically disengage the said catch by employing a
rounded or inclined nose on one of the wheel segments, which on being expanded or
contracted comes in contact with the said catch and releases it from the cam. A spring
controlled by a pawl, pin or catch preferably arranged to be operated by the foot is
employed to rotate the said cam disc backwards when it is required to restore the
parts to their original position.
I preferably so arrange the parts forming my improved mechanisin that the action
of holding the cam disc stationary expands the wheel and the said spring rotating such
cam disc backwards contracts the wheel.
A pulley on a spring may be employed to keep the driving chain tight when
the chain wheel is contracted, or a stationary pulley or pulleys may be used for this
purpose.
Dated this 27th day of Mauch 1000

page_text: Improvements in Variable-speed or Speed and Power Driving
Mechanism for Velocipedes.
I, JOHN CLOUGH, of 4, Rose Bank, Manningham, in the County of York, Manager,
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 improvements in that type of velocipede in which a chain'
is employed to communicate motion from the pedal or crank shaft to the driving
wheel, wheels or driving shaft, through the medium of chain wheels formed of segments
one of which is capable of expansion or contraction for the purpose of altering the
relative speed of the pedal shaft and the driving wheel or wheels with the object of
applying greater power to such wheels or increasing their speed.
The said improvements consist in the construction and arrangement of said
chain wheel enabling the segments to each be expanded when disengaged from
the chain and also in the device or devices for controlling such expansion and
contraction.
For this purpose one of the chain wheels, preferably the one on the pedal shaft as it
is usually of larger diameter and more convenient to alter, is divided into three or
more segments each segment sliding in or upon a radial guide fixed to the pedal shaft
and also provided with a projection or recess adapted to engage a cam or scroll disc
loosely mounted by the side of said segment. The said cam disc has two concentric
annular guides the diameters of which bear the same proportion to each other as the
difference between the size of the wheel when fully expanded or contracted and such
concentric guides are each provided with a stop at suitable parts and are there
connected by a short guide passing approximately at a tangent from the
smaller guide into the larger one thus forming a cam in the shape of an irregular
spiral or scroll.
The said projections on each of the segments engage the said annular guides on the
cam disc therefore if such cam disc is held stationary whilst the rotation of the treadle
shaft is continned approximately a revolution such segments are moved away from or
towards the treadle shaft according to whether the said projections are passed into the
larger or smaller annular guide. The said cam dise is held stationary in such a
position that the wheel segments are expanded and contracted one after another when
disengaged from the chain they are thus operated with little friction. The amount of
expansion is also so arranged that the segments are separated the distance of the
pitch of the chain when the wheel is expanded.
I hold the said cam disc in this manner by employing an operating catch pivoted in
a convenient position to be operated by the rider, to engage a projection or its
equivalent (hereinafter called the cam lever) upon the cam disc and hold it stationary
when in contact with said catch. And when the whole of the segments have been thus

page_text: +
operated I automatically disengage the said catch by employing a rounded or inclined
nose on one of the said segments which after expansion comes in contact with such
catch and releases it from the cam. A spring pawl or catch mounted upon the wheel
and arranged to be conveniently operated by the rider is employed to hold the said
cam disc in position with the wheel when released from the operating catch, and a
coiled spring is provided to rotate the said cam disc backwards when is is required
to restore the parts to their original position and the said spring catch is disengaged
from the cam disc.
I preferably so arrange the parts of my improved wheel that the action of holding
the cam disc stationary expands it and it is contracted by the said spring rotating
such cam disc backwards.
To more clearly describe my invention reference is to be had to the accompanying
drawings forming a part of this specification in which similar letters of reference
indicate corresponding parts in each of the figures.
Figure 1, represents an inside elevation of the guide plate for an expanding wheel
of four segments, keyed on to the crank axle and showing two of the wheel segments
in position one expanded and the other contracted.
Figure 2, is an elevation of the complete wheel with the cam disc and segments
represented beneath the front plate by the dotted lines.
Figure 3, is a diametrical section through two of the segments.
Figure 4, is a plan view of the wheel with the segments omitted.
Figure 5, is an outside view of the said guide plate representing the spring
catch disengaged from the cam, and also a dotted representation of such catch in
the position it occupies when engaged with the cam.
Figure 6, is a side elevation of a safety bicycle fitted with my improved wheel.
Figure 7, is a plan view of such wheel on a larger scale also showing the
additional attachments to the bicycle and the method of operating the same.
Figure 8, is a front view of the parts represented in the latter figure.
The guide plate A is keyed by the key B to the crank shaft and such plate is
provided with projections D equidistant apart and adapted to come between each
segment E when the wheel is contracted. The plate A is cut with guides F in which
the guide pieces G formed on the sides of the segments E slide and similar projec-
tions G¹ formed on the other side of such segments also slide in radial guides F¹ formed
in the front plate H which is secured by the screws I to the projections D.
The guides F are continued radially across the boss J of the plate A and the
spokes K of the segments E are arranged to slide in such guides and steady the
segments in any position.
Studs L preferably provided with anti-friction rollers t are secured to each spoke K
and such anti-friction rollers fit in the guides or race M of the cam N. The boss O of
the cam M passes through the central hole of the front plate H and the cam lever P is
keyed to such boss by the key and lies outside such plate at right angles to the
crank shaft projecting slightly beyond the rim of said plate.
An approximately vertical rod Q provided with a handle R conveniently within the
reach of the rider is mounted in suitable bearings S, S secured to the frame work of
the velocipede and is provided with a Tee piece at the bottom having catch arins U
and U normally lying parallel with the crank axle.
Assuming that the machine is running low gear and it is desired to expand the
wheel and increase the speed, the rod Q is rotated slightly on its axis so as to
cause the arm U at the bottom to engage the projecting end of the lever P thereby
holding the cam disc N stationary but the segments E continue to revolve with the
wheel, thus as each one becomes disengaged from the chain T it is expanded or pushed
outwards by reason of the anti-friction roller t secured to its spoke passing into the
outer or larger part of the cam race M and as soon as the whole of such segments are
expanded the inclined projection V on the segment E' comes in contact with the arm U
and disengages it from the lever P. At the same time the catch W passing through
the slot and projecting from the catch lever a pivoted by the screw M¹ to the
plate A, springs into the notch 6 formed preferably in the thickest part of the

page_text: periphery of the cam M and prevents such cam assuming its former position in
relation to the wheel until it is required to contract the segments. To effect this it is
simply necessary to turn the rod so as to enable the arm U' to engage the projecting
end d of the spring catch lever a and thereby moving it slightly upon its fulcrum so as
to pass such catch arm which motion raises the catch W from the cam N, when the
recoil of the spring e fixed at one end to such cam and by the other to one of the
projections D turns the cam backwards and thus withdraws each of the segments in
turn. The spring n fixed to the plate A presses upon the inner end of the catch
lever and tends to spring W into the notch b.
When the machine is running on low gear with the segment wheel contracted there
is a certain amount of slack in the chain T so I may employ a small pulley h to guide
the chain on to the chain wheel of the driving wheel or axle.
My improvements are herein described as applied to a safety bicycle for which
purpose owing to the compact form of the wheel they are particularly applicable,
but it is obvious they may be also applied to tricycles or other velocipedes.
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed I would have it under-
stood that I do not wish to broadly claim expanding segment wheels, but what I
claim is:
1. A segment wheel for velocipedes constructed and arranged so as to operate the
segments or expand and contract them one by one when disengaged from the chain,
substantially as herein shown and described and illustrated in the accompanying
drawings.
2. The combination with a segment wheel, of the projection V and the catch U
substantially as described and illustrated and for the purpose specified.
3. The combination with a segment wheel, of the cam N, the cam lever P,
the spring catch a, and catch arms U and U¹, substantially as herein shown and
described and illustrated.
Dated this 27th day of December 1888.
DRACUP & NOWELL,
Bradford, Agents.