Improvements in Driving Gear for Bicycles or other like Vehicles.
Year: 1897

page_text: Date of Application, 17th Dec.,
1897
Complete Specification Left, 9th Sept., 1898-Accepted, 29th Oct.,
1898
Improvements in Driving Gear for Bicycles or other like Vehicles.
JAMES EDWARD CARTER and SAM AYRTON WRIGHT, Bolt and Nut Manufacturers,
South Darley Street, Halifax, do hereby declare the nature of this invention to be
as follows:-
On the pedal crank axle we mount a spiral wheel (spiral wheels are practically
worm and wheel working in combination that is to say if a worm wheel has 20 teeth
driven by a single thread worm it will require 20 revolutions of the worm for one
revolution of the wheel whereas if the worm has 10 threads then the worm will only
rotate twice to the wheel once this we reverse by making the wheel drive the worm)
the latter gears with and drives another spiral wheel which is mounted on one end
of a shaft and at its opposite end we mount another spiral wheel the latter gears
with and drives a spiral wheel which is mounted on the axle of the back driving
wheel of a bicycle the spiral wheel on the pedal crank axle has a greater number of
teeth in its circumference than the spiral wheel has threads or teeth which it gears
with and the spiral wheel on the opposite end of the shaft has also a greater number
of teeth in than the spiral wheel which is mounted on the axle of the back driving
wheel, these spiral gears are made to suit the ratio of speed of the pedal crank axle
and the back driving wheel of the bicycle these gears are mounted on one side of
the machine only when used for driving the machine but when to be used for
differential gearing and to enable the rider to ascend gradients easily we have two
sets of driving gear by preference one set of gears on each side of the machine and
mount the spiral wheels on the axle of the back driving wheels loose and engage
with a clutch either the one side or the other the spiral wheels are well lubricated
and the end thrust are button or ball bearings.
JAMES EDWARD CARTER.
SAM AYRTON WRIGHT.
Improvements in Driving Gear for Bicycles or other like Vehicles.
We, JAMES EDWARD CARTER and SAM AYRTON WRIGHT, of the Firm of Carter and
Wright, of Hexagon Iron Works, South Darley Street, Halifax, in the County of
York, Nut and Bolt Manufacturers, do bereby 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 driving gear for bicycles and other like vehicles for
imparting motion through a shaft from the crank axle to the driving wheel.

page_text: The object of our invention is to dispense with the driving chain usually employed
and instead thereof to provide an efficient and neat inotor mechanism which will
give an accelerated speed with the same applied power.
To the aforesaid purpose our invention consists in the employment of spiral wheels
or skew gearing for the above named purpose.
In the accompanying drawings illustrating our invention,
Fig. 1 is elevation of so much of a bicycle as is essential to shew the application
of our improvements.
Fig. 2 is an enlarged sectional elevation of part of the mechanism.
Referring to the drawings letter a represents the pedal or crank axle journalled
in bearings in the bottom bracket b, and c, d, the pedal cranks fast on said axle, all
as ordinarily. On the axle a we mount a gear e having its teeth cut at an acute
angle or spirally and known as a spiral or skew gear wheel. These spiral or skew
gear wheels are practically worm and wheel working in combination, that is to say,
if a worm wheel has twenty teeth and is driven by a single thread worm, it will
require twenty revolutions of the worm for one revolution of the wheel, whereas if
the worm has ten threads then the worm will only rotate twice to the wheel once.
This we reverse by making the wheel drive the worm. The said spiral wheel e
meshes with and drives a similar spiral wheel ƒ mounted and secured on one end of
a shaft g extending from the crank axle a to the axle h of the driving wheel h¹ of
the bicycle, and journalled at each end in ball bearings i, ¹, supported by lugs j, j¹
cast or stamped in one piece with the bottom bracket b and back fork k respectively,
the shaft being inclosed by the near back stay brazed at each end to the lugs j, j¹.
On the opposite end of shaft g is mounted another spiral toothed wheel which
meshes with a spiral toothed wheel m mounted on the axle h of the back driving
wheel h¹.
The balls, rest, and are supported in pockets or cups formed in nuts n, n¹,
screwed into the lugs 1, 1, and they enter corresponding concaved recesses in the
faces of the spiral wheels f and as will be seen clearly at Fig. 2. The nuts n, n¹
are turned round to adjust the balls and are locked in position after adjustment by
lock nuts n², n³, or instead of lock nuts we may attach to the lugs j, j sliding
locking dogs or pins adapted to be engaged with recesses or openings in the edges
of the nuts n, n¹.
The spiral wheels e, f, l, m are of equal diameter, preferably, and the wheels e
and have a greater number of teeth in their circumference than the
wheels and m, one ratio we consider very suitable, being fifteen teeth in
the wheels e and to nine teeth in the wheels f, m, but the number of teeth in said
wheels and the proportions one to the other may be varied to suit the required ratio
of speed of the crank axle and back driving wheel.
Although a little more power may be required to drive the aforesaid spiral gears
or motor mechanism than is expended in driving ordinary chain gear, we obtain
ample compensation for this additional expenditure of power, by the greater leverage
which our mechanism gives to the cranks c, d. Apart from the extra leverage given,
the application of the spiral gears as set forth enables a much quicker speed to be
imparted to the driving wheel with approximately the same expenditure of power.
The end thrusts of the wheels f and are borne by the balls i, i¹, and being
in a direction opposed to each other, such end thrusts practically neutralize each
other and establish an equilibrium.
To each lug 7, jlis cast or attached an oil well o, o¹ surrounding the lever
portion of the spiral wheels f and land containing lubricant so as to keep the
wheels well lubricated.
The motor mechanism above described is located on one side of the machine
similarly to the present chain drive. If a differential motion is desired the said
mechanism can be duplicated, a set of gears being placed on each side of the
machine, and the spiral wheels on the back driving wheel axle engaged with and
disengaged from said axle by an ordinary clutch motion, which however, we do
not consider of sufficient importance to shew.

page_text: 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 :-
In bicycles or other like vehicles, the application for driving same, of spiral or
skew wheels, arranged and operating, substantially as herein shewn and described.
Dated this 31st day of August 1808
TASKER & CROSSLEY,
Patent Agents, Halifax, Agents for the Applicants.