An Improved Driving Gear for Cycles.
Year: 1897

page_text: Date of Application, 4th Sept., 1897-Accepted, 27th Aug., 1898
An Improved Driving Gear for Cycles.
We, THOMAS EWART WHITE and CUTHBERT READ, both of Trangie, in the Colony
of New South Wales, Station Hands, 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; -
The object of our invention is to provide a direct driving gear for cycles which
will reduce friction to a minimum.
For this purpose we construct a bicycle having two sprocket wheels one on either
side of the rear wheel of the cycle, operating two pinion wheels, fitted with roller
surfaces fastened on the ends of the hub of the rear wheel of the cycle. The
sprocket wheels, to each of which is attached one of the pedal bars, revolve on
suitable bearings fixed on the frame of the cycle, as far forward of the pinion
wheels which they rotate, as may be found desirable. The sprocket wheels are
somewhat similar in size and shape to the large sprocket wheels of an ordinary
chain cycle, except that the indentations are semicircular in form and are on the
underside of the circumferential ring and that the spokes meet and are attached
to one side of the circumferential ring so as to pass clear of the pinion wheels
and adjustment plates. The semicircular indentations on the interior surfaces of
their circumferential rings are of a size to grip and rotate the rollers of the pinion
wheels.
These sprocket wheels are fixed to the frame of the cycle as far forward of the
centre of the driving wheel as to cause the inner surfaces of their circumferences
to be in contact on the rearward side of the axle of the driving wheel, with the
roller surfaces of the pinion wheels. It is obvious that if the indentations of the
sprocket wheels were in contact with the rollers of the pinion wheels on the side
thereof forward of the axle of the driving wheel that the said driving wheel would
be rotated backwards. The bearings of the sprocket wheels are fixed in the frame
of the cycle, for preference at the angle formed by the frame of the cycle with the
adjustment brackets as shown in our drawings. Each of these sprocket wheels is
rotated by a pedal bar fastened thereto, or forming part thereof, and is so set that
the pedal bars (one on either side of the driving wheel) always lie in the same
straight line as shown in Figure 1 of our drawings. Each of the pinion wheels
consists of two metal discs between which, revolving on screw pins or other
suitable bearings, is a series of small rollers of a size and shape to fit the semi-
circular indentations in the interior circumferences of the sprocket wheels. The
pinion wheels are screwed or keyed on to the ends of the hub of the driving wheel
which they rotate and are held in a proper relative position to the sprocket wheels
by sliding adjustments which consist of two metal rectangular plates each about one
inch in length and three quarters of an inch in breadth sliding by means of a
V-shaped slot as shown in Figure 5 between the arms of a guide bracket which
forms part of the frame of the cycle. Each of these adjustment slides has in its
centre a tapped screw hole into which one end of the axle of the driving wheel
is screwed. When in position the ends of the axle are exactly flush with the

page_text: exterior surfaces of the adjustment slides and no nuts are therefore necessary to
secure them. This fact allows of the spokes of the sprocket wheel revolving with
safety within one sixteenth (10), of an inch of the surface of the adjustment
slides thus diminishing considerably the necessary width of the tread of the pedals.
The ends of the arms of each of the adjustment brackets are connected by a bar
through which passes a screw bolt one end of which is attached to, and governs the,
adjustment slide. The necessary adjustment of the pinion wheel can be effected
by moving (by means of the said screw bolts) the adjustment slides backwards or
forwards as required between the arms of the adjustment brackets..
To more clearly explain the nature of our invention we now refer to the accom-
panying drawings:-
Figure 1 is a side elevation of a cycle showing our driving gear in position X is
rear wheel of cycle herein called the driving wheel. A is one of the sprocket
wheels, B is one of the pinion wheels, C₁ is pedal bar attached to sprocket wheel A,
C is pedal bar attached to the second sprocket wheel on the opposite side of the
driving wheel.
Figure 2 shows elevation of one of the sprocket wheels, engaging one of the
pinion wheels, one of the adjustment brackets with slide, one end of the hub of
driving wheel and the angle of the frame of cycle formed by two of the frame
tubes with the adjustment brackets. B is pinion wheel. Dis circumferential
ring of sprocket wheel showing semicircular indentation on its interior surface.
EE are spokes of sprocket wheel, F is nut securing sprocket wheel to its bearings
fixed to the frame of the cycle. C is pedal bar, H is pedal, J J are frame tubes
of cycle, K is bracket containing adjustment slide and forming part of frame of
cycle being portion of solid joint with JJ. L is adjustment slide moving back-
wards and forwards between the arms of bracket K.
Figure 3 shews sectional elevation of one end of hub of driving wheel, with
pinion wheel attached, also one end of axle of driving wheel screwed into the adjust-
ment plate. R is hub of driving wheel, SS are rollers of pinion wheel, M is end
of axle of driving wheel, L is adjustment slide, K K are arms of adjustment bracket
in which the adjustment slide moves.
Figure 4 is elevation showing angle of the frame of cycle formed by two of
frame tubes with the adjustment bracket. JJ are portions of frame tubes. K is
adjustment bracket between the arms K¹ and K of which the adjustment slide L
is held. N is bar joining ends of arms K' and K to which it may be fastened
in any suitable manner. P is screw-bolt passing through bar N and holding and
governing adjustment slide L. Q is nut of screw bolt P G is tapped screw hole
in adjustment slide L into which ends of axle of driving wheel is screwed. Y is
bearing of sprocket wheel.
Figure 5 is section of adjustment bracket showing V-shaped slot by which it is
held between the arms of adjustment bracket. L is adjustment slide K' and K³
are arms of adjustment bracket. G is tapped screw-hole in slide.
Figure is plan of adjustment bracket, axle of driving wheel and bearings of
sprocket wheel. Y is bearing of sprocket wheel. K is adjustment bracket. Lis
adjustment slide. G is tapped hole in slide. Qis nut of screw bolt which
governs adjustment slide L. N is connecting bar.
Figure 7 is elevation showing one of the pinion wheels and adjustment bracket.
V is circumference of one of the two metal discs which form the sides of the
pinion wheels S S are rollers revolving on the pins T T between the two discs
which form the sides of the pinion wheels. K is adjustment bracket of which K¹
and K are the arms N is the bar joining ends of arms K and K L is the adjust-
ment slide governed by screw P passing through bar N. G is tapped screw hole
in adjustment slide which screws on to end of axle of driving wheel. R is end of
hub of driving wheel on to which pinion wheel is screwed or keyed.
Figure 8 is plan of one end of hub of driving wheel one of the pinion wheels
and one of the adjustment brackets R is hub of driving wheel. Vare the two
metal discs forming sides of the pinion wheels. SS are rollers of pinion wheels.

page_text: K is adjustment bracket. L is adjustment slide. M axle of driving wheel. N is
connecting bar.
Figure 9 shows section of both sprocket wheels with bearings, both pinion wheels,
both adjustment brackets holding slides, also the hub and axle of driving wheel.
DD are circumferential rings of sprocket wheels showing the indentations therein
in contact with the rollers SS of the pinion wheels. YY are bearings of sprocket
wheels. SS are rollers of pinion wheels. LL are adjustment slides screwed on to
the end of axle M. KK are adjustment brackets. C¹ Care pedal bars attached
to sprocket wheels. H¹H are pedals.
In Figure 1. When pedal-bar C¹ is depressed by the foot of the rider and the
sprocket wheel rotated forward, the indentations in its under circumference fitting
the rollers of its corresponding pinion wheel, compel the latter to rotate also and
with it the hub of the driving wheel X to the end of which the pinion wheel is
secured. This operation carries round the second sprocket wheel (on the other side
of the driving wheel) till its pedal bar C arrives at the position formerly occupied
by pedal-bar C₁ when it is in turn depressed and the rotation of the driving wheel
continued. The rollers of the pinion wheels when gripped by the indentations
of the sprocket wheels give a half turn on their bearings and thus obviate the
friction caused by the working of two fixed surfaces (such as cogs or chain and
sprocket) and it is in this reduction of friction that the chief value of our invention
lies. Our adjustment slides are also of great value on account of their great
strength and adaptability they enable the gearing to be adjusted or altered with
ease and by obviating the necessity for securing the ends of the axle of the driving
wheel with nuts they enable the tread of the pedals to be considerable reduced
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:--
1. In the driving gear of cycles, a pair of pinion wheels such as BB whose
operating surfaces consist of a series of rollers such as SS secured to and rotating
the hub of the driving wheel as herein fully described and as illustrated in our
drawings.
2. In the driving gear of cycles a pair of adjustment brackets such as KK
forming part of the frame of the cycle and containing adjustment slides such
as L L holding the end of the axle of the driving wheel and governing and adjust-
ing same.
3. In the driving gear of cycles the combination and arrangement of a pair of
sprocket wheels such as A A with a pair of pinion wheels such as BB and a
pair of
adjustment brackets such as KK containing adjustment slides such as LL as
hereinbefore described and as illustrated in our drawings.
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