Year: 1896

page_text: Date of Application, 3'st Dec., 1893-Accepted, 27th Feb., 1897
A communication from abroad by JOHN WELLS WAINWRIGHT HOPKINS, Civil
Engineer, of the Firm of Hopkins, Gardham, and Tetley, Railway Engineers
and Contractors, Buenos Aires, in the Argentine Republic.
I, JOHN PATRIOK O'DONNELL, of 70 & 71 Palace Chambers, Westminster, in
the County of Middlesex, Chartered Patent Agent, 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 :-
My invention has reference to improvements in friction driving gear for cycles,
and the way in which I carry out my invention is as follows:-
I provide at each end of the ordinary crank axle or driving spindle a disc, said
disc being rigidly keyed thereon, and I form each of the cranks with an enlarged
circular boss which is hollowed out or recessed to a suitable depth to loosely fit
the above mentioned disc on the driving spindle: the boss is enlarged or provided
with a projecting lip on a portion of its circumference, in which lip or projection
are arranged a suitable number of inclined recesses in which are placed balls or
rollers. The centre of the enlarged boss is bored to loosely fit the driving spindle
the crank, working loosely about said spindle, a ball bearing being provided.
Projecting Ings are provided on the enlarged recessed boss for the purpose of
attaching a cover to retain. the balls in the inclined recesses above referred to and
to exclude dust.
As a modification of my invention, in lieu of providing the craak with an
enlarged boss as above described I form the crank in two halves, each 'half or
portion being reduced in thickness or cut away on its inner side for a certain
distance from the driving spiudle end so that when the two portions are joined
together to form the complete crank the reduction in the thickness of the metal
forms a slot or housing for the disc keyed to the driving spindle: at the end of
the slot farthest from the driving spindle the crank is widened by means of a
projection on each edge, an inclined recess being diagonally formed in this
widened pertion in which recess is placed a single ball. This halved or split crank
may be minde by stamping and works loosely on the driving spindle.
With my invention the cranks and pedals do not perform a complete revolution
but have an up and down movement, the driving of the machine being effected by
means of the balls in the before mentioned inclined recesses being jambed or wedged
against the periphery of the disc on the driving spindle and the inclined surface or
surfaces formed in the cranks as hereinafter described. The cranks are brought up,
after each downward movement, into position for depression by means of weighted
ends which counterbalance the pedal ends of the cranks. Or the cranks might be
brought up alternately by being connected together by a cord or other flexible
connection working over a pulley fixed to the frame of the machine.
In order that my invention may be better. understood and more readily
carried into effect will now describe it with reference to the accompanying
drawings.
Figure 1 is a side view of my invention showing the crank with enlarged boss.

page_text: (the cover of the boss being removed), inclined recesses and balls, working about
the disc on one end of the driving spindle.
Figure 2 is a frout view of the same, partly in section, showing the cover screwed
on to the enlarged boss plate.
Figure 3 is a side view of the alternative form of my invention, in which only oue
ball preferably, is used in each divided crank for driving the machine, and Figure 4
is a front view of same, showing a section through the centre of both cranks and
also the bottom bracket.
Figure 3 shows the arrangement of pulley and cord or other attachment running
over said pulley and attached to a suitable part of each crank for the purpose of
returning to the thrusting down position, each crank alternately ensuring a steady
pedalling action on the machine.
Figure 6 is an alternative method in which I do away with the pulley and cord
attachment and substitute in their stead a counterbalance weight at the end opposite
to the pedal end of each crank such weight being sufficiently heavy to bring each
crank up to its thrusting down position alternately.
The same letters refer to the same parts in the several figures of the drawinge.
a a are the cranks having the enlarged bosses b b with a projecting lip or
pocket c, in which are formed the inclined recesses d carrying balls or rollerse: are
the discs keyed to the driving spindle g: h are the lugs on the boss b by means of
which the cover j (Fig. 2) is attached. is the ordinary driving chain wheel
keyed to the spindle y. In Figures 3 and 4 is the split crank widened by means
of projections m m', each half of the crank being reduced in thickness forming the
recess or slot n (Fig. 4) for the disc f to work through. o is the inclined recess.
formed in the widened portion m m' of the crank in which recess works the ball p.
In Figure 5 g is the connection between the two cranks, working over pulley r,
whereby one crank and pedal is raised as the other is depressed s. (Fig. 6) is the
weighted end of the crank which automatically raises the pedal end when the
pressure of the foot is removed. This weighted end is shown applied to one form
of my machine but it may be applied suitably to the direct crank form. t are
suitable stops attached to the framing of the machine projecting outwards and
preventing a backward movement of the cranks beyond a certain distance.
The action of my invention is as follows:-
Referring to Figures 1 and 2, on the rider depressing the pedal end of the
crank a, thereby moving the boss b round on the periphery of the disc f, the balls e
in the inclined recesses d'are forced or wedged against the disc edge by the narrow
or shallow ends of said recesses d and the crank being thus in its downward movement
geared to the spindle g, motion is communicated to the chain wheel, which is
also keyed to spindle thereby driving the machine, the cranks being raised
alternately into position ready for depression either by means of the connection q
running over pulley r (Fig. 5) or by the arrangement of weighted ends s(Fig. 6).
During the upward movement of the crank a the boss b works loosely on the
disc the shallow ends of the inclined recesses d'being moved away from the balls e
which take their bearing in the deep ends of said recesses and travel loosely round
the periphery of the disc 1.
The action with regard to Figures 3 and 4 is similar the ball p in the recess o
being wedged or jambed against the edge of the disc as the crank is thrust down,
the ball dropping away from the edge of the disc when the pressure on the crank
is released and the crank commences to ascend: when the crank moves upward the
ball returns to its engaging position in the inclined recess, that is to say, in position
to be again wedged against the disc f when the crank is depressed. Either means
for raising the pedal ends of the cranks in this case may be adopted as is shown in
Figures 5 and 6:
In lieu of the discs being fixed on the chain wheel spindle 9 they may be
placed ou the ends of the back wheel spindle which could be prolonged to project
beyond the frame of the machine at either side, the cranks or levers a or being
made sufficiently long for the pedals to be in the correct position for operation.

page_text: It is obvious that by such an arrangement the chain wheel and the usual driving
chain would be dispensed with, the machine being driven direct from the back.
wheel.
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. In driving mechanism for cycles, the combination of a driving shaft or
spindle and cranks working loose on same in their upward movement, but being
fast on. same in the downward movement through a ball or balls being jambed on
the periphery of discs (one fixed on either side of the spindle) by means of inclined
recesses in the cranks, acting substantially as herein described and as illustrated
in the accompanying drawings.
2. In driving mechanism for cycles, the combination of parts substantially as-
herein described and illustrated in the accompanying drawings.
Dated this 31st.day or December 1890.
JOHN P. O'DONNELL,
Applicant.
JOHN P. O'DONNELL,
Applicant.