IMPROVEMENTS IN BICYCLES, TRICYCLES, AND OTHER VELOCIPEDES
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by John Bradshaw and John Bradshaw
Junior at the Office of the Commissioners of Patents on the 17th November
1883.
JOHN BRADSHAW Mechanical Engineer and JOHN BRADSHAW Junior Accountant
both of Pagefield, Wigan, in the County of Lancaster "IMPROVEMENTS IN
BICYCLES, TRICYCLES, AND OTHER VELOCIPEDES
"
Our invention has for its object improved means or apparatus for increasing
as required the speed or the power of bicycles tricycles and other velocipedes at
the option of the rider and consists of peculiar arrangements and combinations of
gearing which may be brought into and thrown out of action for the purpose of
increasing either the power or the speed according to the purpose for which the
velocipede is employed.
In carrying out my Invention as applied to bicycles for example I form the hub
of the driving wheel hollow and fit in the interior of each end thereof a plate held
stationary with the fork of the Machine These end plates carry bearings for the
axle of the pedals (which also works in the ordinary bearings carried in the fork
in the usual manner) and two axes each carrying toothed wheels capable of being
brought into and out of gear with other wheels mounted on the pedal axle.
The gearing is so arranged that the travelling wheel may be caused to make
the same number of revolutions as the crank or the number of revolutions of the
wheel may be increased or diminished according to the proportions of the toothed
wheels brought into gear for example if I wish to gain a speed of 1/2 to 1 a wheel
having 26 teeth mounted on the pedal axle is made to gear with a pinion having
12 teeth mounted on one of the other two exes before referred to and on this axis
is also mounted a wheel having 20 teeth in gear with a pinion having 10 teeth
mounted on the other of the two axis which latter axes also carries a wheel
having 20 teeth in gear with an internal wheel of 60 teeth fitted to the interior
of the hollow hub
This combination of gearing imparts a revolution to the wheel of 156 to 1
revolution of the crank or pedal axle but by throwing these wheels out of gear and
bringing others into gear the relative speeds may be varied accordingly either to
increase or diminish the relative number of revolutions of the wheel to those of the
crank

page_text: In order to enable the rider to alter the combinations of the gearing as required
The gear wheels on the pedal axle are capable of sliding longitudinally thereon and
are brought into the required position by means of a screw key working in a nut
or tapped sleeve fitted to one of the bearing plates in such a manner that by
turning the said nut or screwed sleeve the screw is caused to move longitudinally
and carry the wheels on the pedal axle with it and thus adjust the position of
the gearing and bring any combination into operation as required whether to
increase the speed for racing purposes or to reduce the speed and increase the power
to facilitate the climing of hills.
According to another modification I arrange on both sides of the hub of a
bycycle three wheels one being carried on the axle of the pedal and the other two
mounted on bearings in the fork. These wheels should respectively contain in
order to gain a speed of 11 to 1 (for example) 30, 26 and 20 teeth the largest
wheel being fixed on the pedal axle and made to gear with the wheel containing
26 teeth and which is fitted to work loose on its axle and gears with the wheel
containing 20 teeth which latter wheel is fixed on the centre axis of the machine
It is obvious that other proportions may be employed to obtain different speeds.
According to a further modification in place of gearing I employ on either side of
the hub of the Machine two pulleys each having two grooves and fitted to the
fork of the machine in a similar manner to the toothed wheels described in the
last modification and worked by means of a steel or other rope tightened to the
tension required by means of a screw and lock-nut. Or instead of grooved pulleys
2 wheels arranged on either side of the machine may be worked by chain gearing
in a similar manner and for a similar purpose as the arrangements herein before
described.
Altho' I have described my invention as applied to bycicles it is obvious that it
is equally applicable to tricycles and other velocipedes.
By the arrangements hereinbefore described the saddle or riders seat may be
fixed on the "backbone" nore towards the rear than is usual and in a better
position for exerting his power when driving whilst at the same time the safety
and comfort of the rider is increased