Improvements in Cycles and in Chainless Gear therefor.
Year: 1896

page_text: Date of Application, 10th Nov., 1896"
Complete Specification Loft 12th Feb 1807 Accepted 21st Aud
1807
PROVISIONAL SPECIFICATION.
Improvements in Cycles and in Chainless Gear therefor.
1, WILLIAM LORENZO BROWN of 103 Leith Walk, Edinburgh, North Britain,
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in cycles and in chainless gear therefor.
I dispense with the usual driving chain and in licu thereof I employ tooth gearing.
By means of my arrangement of tooth gearing, I am enabled to bring the two wheels
of the bicycle much closer together so that the weight of the rider has less straining
effect on the bearings of the wheels. Also, by thus reducing the length of the bicycle
it is more easily stored. The cycle can also be more readily guided or turned and
other advantages are obtained by my said arrangement of gearing.
In the carrying out of my invention, I may use the same diamond shaped frame as
heretofore. The under or diagonal tube is forked to receive the rear or driving
wheel and by means of which said rear wheel may be brought up close to the front
wheel. There is the usual front fork for the front wheel with the usual ball head. I
eruploy the usual top horizontal tube and the usual upright forked seat tube, the said
tube being preferably about the same slant as the front fork.
The ends of the fork of the under or diagonal tube are fitted in separate brackets.
Each bracket has within it two sets of ball bearings to receive the driving axles upon
the ends of which the cranks are keyed. Instead of there being one driving axle,
there are two short axles, one on each side of the machine with the rear driving
wheel between them. The boss of each crank carries an internally toothed wheel.
Gearing with this wheel is a pinion which is keyed to each side of the limb axle of the
driving wheel; the axle of the driving wheel running in ball bearings. The brackets
carrying the cranks are connected to the forked ends of the seat tube by being brazed.
thereto, through the medium of a tube piece or arm of each bracket, each piece being
fitted into each end of the seat tube. The journal of the driving wheel is connected
to the arms of the brackets by means of bolts. Thus on operating the crank, rotation
is given to the driving wheel through the medium of the internally toothed wheel
and pinion.
Dated this Oth don
vember 1900

page_text: same is to be performed, to be particularly described and ascertained in and by
the following statement :-
This invention relates to improvements in cycles and in chainless gear therefor.
I partly dispense with the diamond frame in general use retaining only the front
fork and handle bar and horizontal tube. To this I braze or otherwise fix a diagonal
tube forked to carry the driving gear and wheel and between this diagonal tube and
the horizontal tube I braze or otherwise fix an upright forked seat tube or pillar, the
said tube being preferably about the slant of the front fork, thus forming a triangular
frame.
I dispense with the usual bottom bracket, driving, chain, wheel and chain and in
lieu thereof I employ tooth gearing. By means of my arrangement of tooth gearing
I am enabled to bring the two wheels of the bicycle much closer together so that the
weight of the rider has less straining effect on the bearings of the wheels, also by thus
reducing the length of the bicycle it is more easily stored. The rider can also turn in
less space on a narrow road; and being directly above the driving gear the driver can
put greater driving power into the gear, giving partly the weight of his body as well
as the power of his muscle; and other advantages are obtained by said arrangement
of gearing.
But in order that my said invention may be more readily understood and easily
carried into effect I will proceed to describe the same with reference to the
accompanying drawings in which :-
Fig. 1 is a side elevation of a chainless bicycle constructed in accordance with my
said invention.
Fig. 2 is an end elevation of the same.
Fig. 3 is a sectional plan of the driving wheel and gear.
Fig. 4 is an enlarged side view of the driving gearing.
Figs. 5 and 5 are side elevation and plan respectively, of a modification with
regard to the teeth of the toothed gearing.
In carrying out my invention I use my new triangular frame as described above.
The ends of the forks of the under or diagonal tube A are fitted in separate brackets
at M, at each side of the driving wheel B. Each of these brackets has within it two
sets of ball bearings g to receive the driving axles H upon the ends of which the
cranks J are keyed. There are therefore two short axles H one on each side of the
machine with the rear or driving wheel B between them as shown more particularly
in Fig. 3 which view however only shews the gearing of the one side of the driving
wheel, the gearing at the other side being precisely similar.
The boss of each crank J carries an internally toothed wheel K. Gearing with
this wheel is a pinion L which is keyed to each side of the hub of the driving wheel
which axle runs in ball bearings as usual. is the milled disc for the axle b
ordinary locking cones.
The arrangement of the internally toothed wheel is shown at both sides of the
driving wheel in the end view Fig. 2; the other views only show one side of the
machine.
The crank axle H with its internally toothed wheel K which gears into the pinion L
on the driving wheel axle is shewn in enlarged detail in Fig. 4.
I may employ the ordinary construction of an internally toothed wheel, as shown in
Fig. 4.
But I may also use a novel form of teeth for the internally toothed wheel.
This consists in the employment of steel pins k Figs. 5 and 5 rivetted into the
flange of the driving disc and with a strengthening ring k and on these pins place
small steel rollers, but I may also make these pins, which engage into the teeth of
the pinion, solid. as shewn in the drawings.
The bracket pieces which carry the two short crank axles, have three tubular
projections marked respectively M, M1 M² as shewn more particularly in Fig. 4. The
projections M have the ends of the forks a brazed or otherwise secured thereinto or
thereto, to the middle projection M of the bracket is secured the ends of the forks f

page_text: of the saddle supporting tube; and the bearing of the pinion L is connected to the
rear projection M2 of the bracket by means of gland and bolt or split sleeve.
Thus on operating the crank, rotation is given to the driving wheel B through the
medium of the internally toothed wheel K which rotates with the crank axle H. The
said internally toothed wheel gearing with the pinion which is keyed to each side of
the axle of the driving wheel.
I do not limit myself to the precise construction of the bracket to which the forked
diagonal tube A, the saddle tube F and the journal of the driving wheel are
connected. The means by which I prefer to connect the driving wheel journals to
the crank brackets is shewn more particularly in Fig. 4 that is to say I may employ a
split sleeve adapted to be bound to the projection M of the bracket by bolts m as
shewn.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is :-
1. The improved chainless cycle with the new pattern of frame, substantially as
hereinbefore described and shewn in the accompanying drawings.
2. The combination of the internally toothed wheels K provided on the crank
axles H and the toothed pinions L provided on the driving wheel axle b, arranged
and working substantially as hereinbefore described and shewn in the accompanying
drawings.
3. The arrangement and construction of the forked diagonal tube A and the upright
forked seat tube F, in combination with the toothed gearing, substantially as and for
the purpose herein before described and shewn in the accompanying drawings.
Dated this 11th day of February 1897.
JOHNSONS,
115, St. Vincent Street, Glasgow, Applicant's Agents.