IMPROVEMENTS IN VELOCIPEDES
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by John Ladbury Emary at the Office
of the Commissioners of Patents on the 4th October 1880.
JOHN LADBURY EMARY, of Canonbury Grove, Islington, in the County of
Middlesex. "IMPROVEMENTS IN VELOCIPEDES."
My Invention relates to improvements in the driving mechanism of velocipedes,
and is designed to enable the rider to propel the vehicle with less exertion than
those commonly in use.
In all velocipedes in which the power of the rider is applied to the driving
wheels by means of cranks there is a great loss of power and consequently a waste
of the rider's strength, owing to much of the power exerted by the rider being
spent on the bearings when the crank is at a certain point in its revolution, and it
is only at a small part of each revolution that the power of the rider is fully
employed to propel the machine, in consequence of the amount of leverage in
of its
the crank varying with the position it assumes during the course
revolution.
But according to my Invention improved mechanism is provided by means of
which the power exerted by the rider is used in a direct and continuous manner
to propel the vehicle, the leverage provided being equal during the whole of the
stroke.
My Invention does not consist in the build or form of the body of the machine,
and my improvements may be applied to many existing velocipedes, as a new form
of driving apparatus which I propose to construct in the following manner in order
to ensure the advantages above indicated.
On the shaft or axle of the driving wheel or wheels, I propose to affix two small
wheels of a convenient diameter having teeth on their outer edge, and at the back
and connected to each of these wheels I place a sliding bar or rod having on it a
number of moveable teeth which are free to move in an upward direction only.
When the bar is forced upwards, the teeth on the bar not being free to move
downwards catch against the teeth on the smaller wheel and propel the latter
round and with it the axle of the driving wheel, but as the teeth on the bar are
free to move upward, the small toothed wheel is free to revolve during the
The two sliding
downward movement of the bar, or when the latter is at rest.
bars are moved upward alternately by means of levers attached to the body of the
machine and to which the feet (or hands) of the rider are applied, and in order to

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effect the alternate return of the bars, I may adopt either of the following methods
whichever may best suit the machine to which my improvements are being
adapted. I may place a pulley in a convenient position at the extremity of the
sliding bars, and over this pulley I may pass a cord the ends of which are attached to
the sliding bars, so that as one bar descends it would be made to pull the other
upward and so bring it into position to be operated upon at the next stroke. In
some cases I may use two pulleys on a level with each other instead of one pulley,
if the width between the sliding bars requires it. By another method I may place
a ratchet on the inner side of each sliding bar, and between the ratchets a toothed
wheel in such a manner that as one bar descends it will cause the said wheel to
revolve and carry with it the other bar in an upward direction.
When it is desired that the sliding bar should be in front of the toothed wheel
so as to suit the kind of lever that is employed, I may construct the driving
apparatus in the following manner-Instead of placing the moveable teeth on the
bar, I may place them on the wheel and the fixed teeth on the bar, so that as the
teeth on the wheel would be free to move in an upward direction only, they
would be caught by the teeth in the bar as it descends, and the small teeth would
thus be driven round, but as the bar ascends the teeth in the wheel would be
moved upward and thrown out of gear.
In adapting my improvements to velocipedes which have one large driving wheel
behind, I may place the sliding-bar horizontally above the toothed wheel and
provide for the return action of the bars by means of a cord and pulley as before
described.
Instead of using the above arrangements I may obtain the same results by
employing fixed teeth both on the bar and small driving wheel, and instead of
fixing the small driving wheel rigidly on the axle, I may place on the axle a small
ratchet wheel which is acted upon by one or more pawls attached to the small
driving wheel, thus causing the axle to revolve with the small driving wheel in its
forward movement, while the axle may continue to revolve forward during the
backward action of the small driving wheel.
By another method I may affix on the axle of the driving wheels two small
ratchet wheels, and side by side with them two larger wheels not rigidly affixed to
the axle, having on each of them one or more pawls acting upon the ratchet wheels.
Each of the larger wheels has teeth upon its outer edge over which a chain band is
passed in such a manner that the teeth of the wheel are caught in the links of the
chain, which latter is attached at one end to the lever which is worked by the
rider's feet, the other end being passed over a pulley and continued over the other
toothed wheel and is then attached to the other lever. It will be seen that as one
lever descends it will pull the chain, which will cause the toothed wheel to rotate
forward, carrying with it the ratchet wheel together with the axle of the driving
wheel, while at the same time it will pull back the other wheel and raise the other
lever.