Year: 1896

page_text: 1, HENRY GEORGE HEWITT, of 35, Pond Street, Hampstead in the County of
London, Artist, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in cycle driving gear.
According to my invention I mount on the crank axle a worm or cog wheel and
I arrange in conjunction with the said wheel a worm or endless screw. This worm
is mounted or formed on one end of a spindle supported in suitable bearings
attached to the cycle.
The other end of the spindle is also provided with a worm or endless screw which
gears with a worm-wheel fixed on the axle of the driving wheel of the cycle.
With this construction it will be obvious that when the cranks are operated by
'the rider the worm wheel on the crank axle will rotate thereby rotating the worm
in gear with it so as to actuate the worm wheel on the axle of the driving wheel
through the medium of the second worm.
Dated this 29th day of October 1896
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
I, HENRY GEORGE HEWITT, of 35, Pond Street, Hampstead in the County of
London, Artist, 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 cycle driving gear.
According to my invention I mount on the crank axle a worm or cog wheel and
I arrange in conjunction with the said wheel a worm or endless screw. This worm
is mounted or formed on one end of a spindle supported in suitable bearings
attached to the cycle.
The other end of the spindle is also provided with a worm or endless screw which
gears with a worm-wheel fixed on the axle of the driving wheel of the cycle.
To enable my invention to be fully understood I will describe it by reference to
the accompanying drawings, in which :-
Figure 1 is a sectional elevation of cycle driving gear made according to my
invention, the said gear being shewn applied to the driving wheel of a bicycle;
and,

page_text: Figure 2 is a plan of the said gear.
Figures 3 and 4 are views similar to Figures 1 and 2 respectively of a slightly
modified construction.
a is the bicycle wheel and b the axle thereof; c is the bottom bracket of the
bicycle frame; d is the pedal axle mounted therein and e, e are the cranks keyed
upon the said axle d. All these parts are of ordinary construction.
f is the worm or screw gear wheel mounted upon the pedal axle d and g is the
worm or endless screw arranged to gear therewith. h is the spindle, upon one end
of which the worm or endless screw g is fixed and i is the worm arranged upon
the other end of the spindle h, the said worm i being arranged to gear with the
worm or screw gear wheel secured to the hub of the wheel a of the bicycle. The
worms and worm wheels are made of long pitch.
In the arrangement illustrated in Figures 1 and 2 the spindle h rotates in
adjustable ball bearings k, k provided in one of the bottom stays which is
enlarged to receive the said spindle and is secured to the front tube m of the frame
of the bicycle instead of directly to the bottom bracket c as is ordinarily the case.
The worm wheels f and j are in this construction shewn enclosed in casings f
and secured to the bottom stay 1; these casings may contain a lubricant if
desired.
In the modification shewn in Figures 3 and 4 the spindle h is not enclosed in
the bottom stay as in the previous modification but is mounted in bearings k, k
fitted at one end to a bracket n formed as an upward extension of the bottom stay
and at the other end to a bracket o secured to the front tube m of the machine.
With this construction of driving gear it will be obvious that, when the
cranks e, e are operated by the rider in the usual manner, the worm-wheel fon
the crank or pedal-axle d will rotate, thereby rotating the worm g in gear with it
so as to actuate the worm i through the medium of the spindle h, the said worm i
causing the worm wheel j and consequently the bicycle wheel a to rotate.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is :-
1. The improved driving gear for cycles consisting of a worm wheel mounted
upon the crank or pedal axle and gearing with a worm mounted upon one
end of a spindle the other end of which carries a worm gearing with a
worm wheel secured to the hub of the driving wheel of the cycle, substantially as
hereinbefore described.
2. The improved driving gear for cycles herein before described and illustrated
in Figures 1 and 2 and 3 and 4 respectively of the accompanying drawings.
Doted this 28th day of July 1897
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.