An Improved Variable Driving Gear and Brake for Cycles.
Year: 1898

page_text: Date of Application, 1st Mar., 1898-Accepted, 21st Jan., 1899
COMPLETE SPECIFICATION.
An Improved Variable Driving Gear and Brake for Cycles.
I, JOHN NOEL CAREY, of No. 63, Melbourne Road, Williamstown, near Mel-
bourne, in the Colony of Victoria, Gentleman, 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 improved variable driving gear and brake has been devised with a view to
supplying cyclists with a gear which will give them perfect control over their
machines under all circumstances-that is to say-it is designed so that the gear
can be altered to whatever is found best suited to the requirements at any particular
time without having to dismount from the machine, whilst at the same time
in coasting a brake is provided which is operated by merely keeping the feet
stationary.
As a matter of convenience I will, in order to facilitate a clear understanding
of my invention, describe it by reference to the accompanying drawings in
which,
Figure 1 is a side elevation partly in section, of my improved variable driving
gear and brake for cycles, showing same as applied to the hub of the rear wheel of a
chain driven bicycle.
Figure 2 is a vertical transverse section on line 2-2 Figure 1.
Figure 3 is a side elevation of a bicycle drawn to a smaller scale and showing it
fitted with my improved variable driving gear and brake.
The same letters of reference indicate the same parts in all the figures.
A represents the hub of the main drive wheel of a bicycle showing it constructed
in the usual barrel form and constructed with the usual flanges b for the attach-
ment of the inner ends of the spokes B. It is mounted on ball bearings C¹ carried
by a spindle D secured at each end between the back forks of the frame of the
machine in the usual way. E represents an extension of the hub which is screwed
or otherwise secured upon one side or the other thereof, and which carries through
the medium of ball-bearings the hub f of a sprocket wheel F to which motion may
be imparted by a chain G in the ordinary way from a similar sprocket wheel upon the
crank axle. "One great feature of my improved gear is, that the sprocket wheel F
and the sprocket wheel on the crank axle can be the same size with this advantage
gained, that the drive chain will travel slowly, and by acting upon a large
pinion will have more direct effect in turning the wheel than it would have if it
were acting upon only a small pinion. The hub f of the sprocket wheel F has
projecting from it a set of studs h upon any of which can be placed an intermediate
or idle pinion, such as is illustrated at H, said pinion varying in size according
to the highest gear desired by the rider. This pinion H is arranged to gear with
another pinion I keyed or otherwise secured to the extension E of the hub A,
so as to rotate therewith, whilst the outer periphery of said pinion H is arranged
to gear with the teeth of an internally toothed wheel or drum J, which is fitted
loosely over the gearing and is not connected directly with any part of the
mechanism, in other words it is, under normal circumstances, a loose internally
toothed drum.

page_text: The outer face of this loose drum J is formed with a coned recess in which fits
an expansion locking disc K constructed as illustrated in Figures 1 and 2 with
a number of radial parts each of which forms a stout spring. The whole of this
is dish-shaped and its periphery just fits within the recess of the drum J.
Upon the spindle 1) is a bushing carrying a nut fitted with a lever k
whereby it can be partially rotated (preferably through the medium of suitable
connecting rods rack and pinion and a handle as shewn in Figure 3) so as to
force it against the face of the locking disc K, the effect being to compress said
disc thereby forcing its periphery outwards against the recess k¹ of the drum J,
and thus securely holding said drum against rotation. The effect in such a case
will be to communicate a proportionately accelerated motion to the pinion I, and
therefore to the drive wheel of the machine, because, as the sprocket wheel F
rotates and carries the pinion H round with it, this latter by rolling around the
interior of the drum will rotate the pinion I in the opposite direction, and thus
the accelerated rotary motion will be imparted to said pinion I in a certain degree
according to the proportion between the two pinions H and I. If the nut
slacked back, the spring behind the locking disc K. will release said disc, the
effect being to allow the drum J to revolve in the same direction, but only at a
rate inversely proportional to the pressure set up by the locking disc K. The
gearing by this means will be reduced down to a proportionate extent until the
travel of said drum is equal to the travel of the sprocket wheel F, the effect on
the gearing being that the crank axle will make one revolution for each revolution
of the back drive wheel, that is, the gearing will be reduced down to twenty six
or twenty eight inch according to the size of said back wheel.
is
In practice I propose to arrange my improved gearing so that when the drum J
is locked the gearing will be set at the highest gear found suitable for the rider
on good roads.. If he wants to reduce it he can easily do so down to say twenty
six, or eight, by merely slacking back the nut k³.
The gear can be used as a brake by more or less slacking back this nut and
keeping the feet stationary the effect being that the friction set up against the
drum will act as a very efficient brake which can be relied upon under all circum-
stances, will be continuous in action and not liable to get out of order.
It will be obvious that the nut for operating the locking disc K can be rotated
in many different ways, but it is preferable to connect the arm or lever k by the
gearing illustrated in Figure 3 to the rack and pinion L.
If it is preferred to use chainless drive gear instead of sprocket gear in connection
with my invention, it will simply involve the substitution of a bevel pinion or
mitre wheel, for the sprocket wheel F and a shaft with bevel pinions on the ends
for the chain G as will be readily understood by all practical cycle manufacturers.
One great advantage of my improved gearing is that it can be fixed to an
ordinary machine by the purchaser without requiring a large amount of mechanical
skill.
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 herein described gear and brake for cycles consisting of the various parts
constructed, arranged and operating substantially as and for the purposes specified
and as illustrated in the accompanying drawings.
2. In variable driving gear for cycles an internally toothed drum (such as J)
capable of being either locked in its stationary position or of being retarded as
to its rotation to a greater or lesser degree according to the gearing required sub-
stantially as and for the purposes specified and as illustrated in the accompanying
drawings.
3. In variable driving gear for cycles a loosely mounted internally toothed drum
or ring (such as J) in combination with an idle pinion (such as H) in gear with

page_text: another pinion (such as I) mounted upon the hub of the drive wheel substantially
as and for the purposes specified and as illustrated in the accompanying drawings.
4. In variable driving gear for cycles a loose internally toothed drum (such
as J) in combination with a locking disc (such as K) whereby said drum can
sither be held against rotation or can be allowed to rotate at any speed required
substantially as and for the purposes specified and as illustrated in the accom-
panying drawings.
5. In a variable driving gear and brake for cycles a locking disc (such as K)
having radial springs with a circular periphery and made dish-shaped so that
on being compressed laterally it will expand circumferentially substantially as
and for the purposes specified, and as illustrated in the accompanying drawings.
Dated this Twenty-fourth day of January, One thousand eight hundred and
J. NOEL CAREY.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.