IMPRove- MENTS IN VELOCIPEDES
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Thomas Butler at the Office of the
Commissioners of Patents on the 8th November 1880.
THOMAS BUTLER, of Wokingham, in the County of Berks, Machinist. "IMPRove-
MENTS IN VELOCIPEDES."
My Invention relates to velocipedes, and is more particularly applicable to
tricycles, although it may in some cases be advantageously applied to bicycles.
The chief object of the said Invention is to provide improved means for
communicating to the driving wheels of a tricycle the motion imparted to the
crank-shaft by the fect of the rider, whereby I am enabled to utilize the driving
power in an advantageous manner, to employ smaller wheels than are ordinarily
used, thereby reducing the weight of the machine, and to dispense with the chain
now in general use for communicating motion.
In carrying my said Invention into practice I provide two driving wheels, a
convenient diameter for each of which will be twenty four (24) inches, these
wheels being secured upon a frame in such a manner that the rider may sit between
them upon a seat suitably arranged upon the said frame. The steering wheel is
preferably arranged at the rear, and a rod leading therefrom extends to a handle in
a convenient position near the seat. The crank-shaft having two cranks furnished
with suitable pedals has its bearings in downwardly projecting arms forming part
of the frame of the machine. Near each end of the crank-shaft, and rigidly
attached thereto, there is a wheel or disc having a rim or annular flange projecting
from the body or web of the said wheel or disc at right angles thereto and around
the edge of the same in an outward direction, that is to say, towards the driving
wheel. This flange is furnished with teeth around its inner periphery, the teeth
being thus concentric with the axis of the shaft. The axles of the driving wheels
are also supported in the arms of the frame and project slightly inside the latter,
and at this inner end each axle carries a toothed wheel rigidly secured thereto and
in such a position that it lies within the aforesaid annular flange, and gears with
the teeth thereof. The bearings of the driving wheel axles are arranged at a
sufficient height above the bearings of the crank-shaft to provide space for the
admission of the said toothed wheels, which will ordinarily be of a sufficiently small
diameter to enter and rotate in the space between the crank-shaft and the inner

page_text: periphery of the aforesaid annular flange; but should it be desirable or necessary
under any circumstances to have these toothed wheels on the driving wheel axles
of a larger diameter than would enter within such space, this may be provided for
by curving the arms of the frame (below the points where the driving wheel axles
pass through the same) inward and upward so that the crank-shaft will have its
bearings in the extremity of the curved portion of the arms and a portion of the
said toothed wheels may then occupy a position below the bearings of the crank-
shafts.
In some cases two forks may be employed as part of the frame, which forks
will extend upward over the driving wheels, and the lower inner extension of each
fork will support the crank shaft, also the inner end of the driving wheel axles.
A plate may be applied to the open side of the flanged wheel or disc, thus enclosing
the toothed portion thereof and the toothed wheel within the same, thereby
excluding dust and preventing all liability of any part of the rider's dress to come
in contact with the teeth.
I provide ratchet-work or the like between the axles and the driving wheels, to
allow either wheel to move faster than its axle when necessary, as for instance
when the machine is moving in a curve.
Motion is imparted to the crank-shaft by the fect of the rider, and consequently
the flanged internally toothed wheels or discs on the said shaft are caused to rotato,
and their rotation being communicated to the toothed wheels on the driving wheel
axles, the driving wheels are operated and the machine is propelled.
I may in some cases use two driving wheels of different diameters, and although
my Invention enables me to employ driving wheels of smaller diameter than is
practicable when the means employed; for communicating the motion of the crank-
shaft to the same necessitate placing the said shaft at a considerable distance from
the driving wheel axles, I may apply my Invention to tricycles having wheels of
any diameter suitable for such machines.
In some cases I may provide the said toothed wheels on one side of the machine
only.
In adapting my said Invention to bicycles, I provide two flanged wheels or discs,
made as above described, and rigidly attached to a crank-axle, one on each side of
the driving wheel, so that as the cranks are operated by the rider's feet they will
cause the said flanged wheels to rotate. Two toothed wheels are rigidly secured
to the axle of the driving wheel, and each one lies within one of the said flanged
wheels so that the teeth of the latter gear with those of the toothed wheels.
bearings of the crank axle are provided in extensions of the fork below the bearings
of the driving wheel axle.
The
In some cases instead of making the wheels on the crank shaft with a flango
having internal teeth, I may provide a disc having projecting pins or pegs which
will gear with the toothed wheels on the driving wheel axles.