IMPROVEMENTS IN DRIVING MECHANISM FOR TRICYCLES
Year: 1881

page_text: LETTERS PATENT to Adam Burdess, of Coventry, in the County of
Warwick, for an Invention of IMPROVEMENTS IN DRIVING MECHANISM
FOR TRICYCLES."
"
(Void by reason of the Patentee having neglected to file a Specification in
pursuance of the conditions of the Letters Patent.)
PROVISIONAL SPECIFICATION left by the said Adam Burdess at the Office
of the Commissioners of Patents on the 18th May 1881.
ADAM BURDESS, of Coventry, in the County of Warwick.
DRIVING MECHANISM FOR TRICYCLES."
"IMPROVEMENTS IN
This Invention relates to improvements in driving mechanism for tricycles, and
has for its object to obtain smoother and easier motion when travelling, combined
with increased speed.
To carry out my Invention I mount upon the framework two friction wheels,
one being attached to the crank axle of the machine, while the other is carried on
a pin which is fixed in a slide moving in a slot in the framework. The first of such
friction wheels is hereafter termed the lower wheel, and the second of such wheels
is hereafter referred to as the centre wheel. A third friction wheel (hereafter
termed the upper or outer wheel, is attached to the driving wheel of the tricycle.
Such upper or outer wheel is actuated by a crank lever jointed to the framework,
and which lever is also attached to the slide carrying the centre wheel. This lever
is raised or depressed by means of a handle, the connecting rod to which is furnished
with a toothed rack which gears into the framework, and thus allows of the lever
being raised or lowered and locked in any desired position. When the lever is
raised it acts upon a spring and forces forward the slide which carries the centre
wheel, thus pressing the wheels closely together and preventing them from
slipping, while it allows them to revolve smoothly. If additional friction be
required, I fit a sliding axle box, provided with suitable springs, either on the
driving wheel or the crank axle, whereby the rider's weight is thrown upon the

page_text: friction wheels, and thus, from the additional friction so created, further preventing
the wheels from slipping.
The slide which carries the centre friction wheel works in a slot formed in the
framework, so that when the lever is pressed against the slide it forces such centre
wheel against the lower and upper wheels, thus producing great friction. By this
ineans when the crank axle is operated the lower wheel is set in motion, and such
motion is thereby communicated to the centre wheel, which in its turn again
communicates such motion to the upper wheel, and this latter being attached to
the driving wheel of the machine thus imparts motion to the tricycle itself.
The lever which presses upon the slide carrying the centre wheel acts also as a
spring, and thus relieves any excess of pressure thereon. Any suitable kind of
lever may be employed, and, if desired, sliding axle boxes with suitable springs
may be fitted to all or any of the driving or friction wheels in order to obtain
increased friction. Or in lieu of such lever arrangement I may force the wheels
together by a screw or other equivalent means, while in order to obtain the requisite
speed and power I may employ two friction wheels only; such wheels may be
thrown either in or out of gear by a lever arrangement, so that when the vehicle is
descending the treadle crank need not be employed. Also, if desired, I make one
side of the machine to work at a slow speed and the other at a quick speed, by so
fitting the friction wheels thereto that one side can be thrown out of action to obtain
power and the other side thrown into action to heighten the speed of the vehicle,
as circumstances may require.