Improvements in Driving Gear for Bicycles, Tricycles and other Velocipedes.
Year: 1897

page_text: Date of Application, 4th May, 1897
Complete Specification Left, 22nd Jan., 1898-Accepted, 12th Mar., 1898
PROVISIONAL SPECIFICATION.
Improvements in Driving Gear for Bicycles, Tricycles and other
Velocipedes.
I, SAMUEL HAMPTON, of Hollydene, Walsall Road, King's Hill, Wednesbury,
in the County of Stafford, Tool Maker, do hereby declare the nature of this invention
to be as follows:-
My invention consists of the construction and arrangement or combination of
parts hereinafter described of driving gear for bicycles, tricycles and other velo-
cipedes, whereby at the will of the rider the speed gear of the velocipede may be
changed and a slow speed, with high power, obtained as when ascending a hill,
or a high speed with reduced power obtained as when travelling along a level
road; or the cranks may be thrown out of gear with the driving chain wheels and
be utilised as foot rests as when descending a hill.
I will describe my invention in connection with a safety bicycle.
I make the crank axle of the bicycle somewhat longer than usual and capable in
addition to a rotary motion of a sliding or endwise movement in the bottom bracket
of the bicycle. I arrange on the crank axle and at each end or side of
the bottom bracket, a chain wheel, the chain wheels being capable of turning freely
on the said crank axle. In the outer side of each chain wheel is a series of equi-
distant holes. On the inner side of each of the cranks is a pin or stud which is
capable of engaging in one or other of the series of holes in the chain wheel adjacent
to the crank.
The chain wheels at opposite ends or sides of the bottom bracket gear by means
of driving chains with chain wheels, preferably of different diameters, at oppo-ite
ends or sides of the hub of the rear wheel of the bicycle.
The crank axle is moved endwise in the bottom bracket by an eccentric pin
on the end of a rod the operating handle of which is within convenient reach of the
rider's hand. The said eccentric pin engages in a groove in or between a pair of
collars on the middle part of the crank axle. Or the said endwise motion of the
crank axle may be effected by the feet of the rider instead of by hand.
When the crank axle is moved endwise to its full extent in one direction, the cran's
at one side is engaged by means of its pin or stud with the chain wheel adjacent to
it and the velocipede is driven at the speed determined by the size of the said chain
wheel with respect to the chain wheel on the same side of the hub of the rear
wheel of the bicycle. By the reverse motion of the rod the crank axle may be
moved endwise into its mid-po-ition in which position both driving chain wheel;
are free of the cranks: or the crank axle may be moved completely over by which
action the other crank is engaged with the chain wheel adjacent to it and the
speed of the bicycle thereby changed.

page_text: The application of my invention to velocipedes other than safety bicycles differs
in no essential respect from its application to a safety bicycle as hereinbefore
described.
W. T. WHITEMAN,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Driving Gear for Bicycles, Tricycles and other
Velocipedes.
I, SAMUEL HAMPTON, of Hollydene, Walsall Road, King's Hill, Wednesbury,
in the County of Stafford, Tool Maker, do hereby declare the nature of my 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 consists of the construction and arrangement or combination of
parts hereinafter described of driving gear for bicycles, tricycles and other velo-
cipedes, whereby at the will of the rider the speed gear of the velocipede may be
changed and a slow speed, with high power, obtained as when ascending a hill,
high speed with reduced power obtained as when travelling along a level
road; or the cranks may be thrown out of gear with the driving chain wheels and
be utilised as foot rests as when descending a hill.
or a
I will describe my invention in connection with a safety bicycle.
I make the crank axle of the bicycle somewhat longer than usual and capable in
addition to a rotary motion of a sliding or endwise movement in the bottom bracket
of the bicycle. I arrange on each end of the crank axle or at each end or side of
the bottom bracket, a chain wheel, the chain wheels being capable of turning freely
on the said crank axle. In the outer side of each chain wheel is a series of equi-
distant holes. On the inner side of each of the cranks is a pin or stud which is
capable of engaging in one or other of the series of holes in the chain wheel adjacent
to the crank.
The chain wheels at opposite ends or sides of the bottom bracket gear by means
of driving chains with chain wheels preferably of different diameters at opposite
ends or sides of the hub of the rear wheel of the bicycle.
The crank axle is moved endwise in the bottom bracket by an eccentric pin
on the end of a rod the operating handle of which is within convenient reach of the
rider's hand. The said eccentric pin engages in a groove in or between a pair of
collars on the middle part of the crank axle. Or the said endwise motion of the
crank axle may be effected by the feet of the rider instead of by hand.
When the crank axle is moved endwise to its full extent in one direction the crank
at one side is engaged by means of its pin or stud with the chain wheel adjacent to
it and the velocipede is driven at the speed determined by the size of the said chain
wheel with respect to the chain wheel on the same side of the hub of the rear
wheel of the bicycle. By the reverse motion of the rod the crank axle may be
moved endwise into its mid-position in which position both driving chain wheels
are free of the cranks; or the crank axle may be moved completely over by which
action the other crank is engaged with the chain wheel adjacent to it and the
speed of the bicycle thereby changed.
Figure 1 of the accompanying drawings represents in side elevation a safety
bicycle to which driving gear constructed according to my invention is applied.
Figures 2 and 3 represent respectively in longitudinal and cross section the

page_text: bottom bracket of the said bicycle and parts connected therewith; Figure 3 is a
side elevation of the chain wheel on the hub of the rear or driving wheel of the
safety bicycle.
"
Figure 4 is a plan of the said bottom bracket and parts connected therewith and
Figures 5 and 6 represent in elevation and plan respectively the operating handle
by which the gear of the bicycle is changed and the said handle fixed in its adjusted
position as hereinafter particularly explained.
Figures 2 to 6 both.inclusive are drawn to a larger scale than Figure 1.
The same letters of reference indicate the same parts in the several figures of the
drawings.
a is the crank axle of the bicycle and a³, a² the collars at the middle of the same
between which the eccentric pin 6 on the operating rod b' is situated and works. The
bottom bracket & has at opposite ends chain wheels e, e capable of turning freely
thereon: By the turning of the operating rod 61 by means of its disc handle b
the eccentric pin b may be made to move the crank axle a longitudinally or end-
wise in the bottom bracket d and thereby bring one or other of the cranks c, c into
engagement with the driving chain wheel e adjacent to it, pins c¹ on the said cranks
taking in one of a series of holes in the disc e fixed to the chain wheel c. The
crank axle a has keys a', a' which on the longitudinal or endwise motion of the
crank axle a travel in key ways in sleeves f, f (see Figure 2) on the crank axle a.
The driving chain wheels e, c are free to rotate at the ends of the bottom bracket as
herein before described when the crank axle a is in the mid-position represented in
the drawings. It will be seen by an examination of Figure 3 that the chain
wheels at the opposite ends of the hub of the rear or driving wheel and driven by
the driving chain wheels e, e are of different sizes but I wish it to be understood
that they may be of the same size the chain wheels on the crank axle in the latter
case being made to vary.
In order to preserve the crank axle a in the position to which it may have been
brought by the turning of the operating rod ba spring locking bolt 9 on the top
horizontal tube of the bicycle frame is made to engage in depressions in a collar
at the head of the said rod b¹ as will be best understood by reference to Figures 5
and G.
Each of the cranks c may be prolonged beyond the crank axle a and the extended
part provided with a second engaging pin c as is indicated in dotted lines in
Figure 2.
The several parts of the arrangement are represented in the drawings in the
positions which they occupy when the cranks are out of action in which positions
the pedals of the bicycle virtually constitute foot rests. When it is wished to
throw one or other of the cranks into engagement with its driving chain wheel
it is only necessary for the rider to turn the disc handle 3 on the operating rod 61
in one or other direction through a quadrant when the motion of the cranks is
transmitted to the chain wheels and the bicycle driven at the desired speed as
hereinbefore particularly explained.
:
The application of my invention to velocipedes other than safety bicycles differs
in no essential respect from its application to a safety bicycle as hereinbefore
described.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that I claim as my
invention:-
The construction and arrangement or combination of parts of driving gear for
bicycles, tricycles and other velocipedes herein before described and illustrated in
the accompanying drawings; the said construction and arrangement of parts con-
sisting of a crank axle provided with chain wheels at opposite ends capable of
turning freely on the bottom bracket, the said crank axle being capable.in
addition to a rotary motion of a limited longitudinal or endwise motion in its
bottom bracket the said crank axle having at its middle a neck or groove in which

page_text: neck or groove an eccentric pin on an operating rod is situated and works the
cranks on the said crank axle being situated at such a distance apart that on the end-
wise motion of the crank axle in one or other direction one or other of tho
said cranks can be thrown into engagement with the adjacent chain wheel on the
end of the bottom bracket or the said cranks may be made to occupy a mid- or 5
non-acting position substantially as hereinbefore described and illustrated in the
accompanying drawings.
Dated the Nineteenth day of January 1808