Improved Bicycle Driving Gear.
Year: 1897

page_text: Date of Application, 4th Nov., 1897-Accepted, 26th Feb., 1898
COMPLETE SPECIFICATION.
Improved Bicycle Driving Gear.
JOHN ALEXANDER CALDWELL, Vancouver; British Columbia, Canada, Mechanic,
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 relates to bicycle gearing, and consists essentially of arranging
a multiplying driving gear directly to the hub and axle of a bicycle driving wheel
and adapted to be operated by the ordinary cranks and pedals, or by levers. The
objects of my invention, is to provide an improved bicycle gear, whereby great
speed and power, with little friction and small amount of foot-travel, and also slow
foot-movement may be obtained; to be compact dust proof, and readily adapted to
any shape of bicycle. Having the foregoing objects in view, the invention con-
sists in the novel construction and arrangement of the several parts as will appear
more fully hereafter.
Reference being made to the accompanying drawing, in which:
Fig. 1, is a detail side elevation of the gearing applied to the bicycle wheel,
showing the casing cut away on the line XX.
Fig. 2, is a cross-section on the line X X of Fig. 1.
Fig. 3, is a perspective view of the rings 7 and 8, showing construction, and,
Fig. 4, is a side elevation, showing a bicycle equipped with my invention.
My improved mechanism can be applied to the front wheel of a bicycle, in which
case it would be preferable to lengthen out the cranks to the usual length, and
attach the ordinary pedals. The rear wheel could then be reduced in diameter,
and act as a small drag-wheel, as in the ordinary bicycle or high-wheel; but, in
the present case the gear is shown applied to the rear wheel, and is operated by
levers. The hub of the rear wheel is shown at 1, Fig. 2, the same being of
ordinary construction, and having a pinion 2 at the one end thereof. The
numeral 3 designates the axle, but instead of being stationary as ordinarily, the
same is journalled in the bicycle frame, and turns on sets of balls 4; the usual
sets of balls 5 interpose between the hub and the axle, and said axle has screw-
threaded extensions at its ends. The numerals 7 and 8 designate rings, which
are brought together at 10¹, and are secured by screws or other fastenings. The
ring 7 has arms extending inwardly, and they are connected by a hub at their
inner ends, and the said hub is securely fastened to the end 6 of the axle. The
ring 8 is without arms, but it is connected to the axle by being firmly attached to
the ring 7, as shown in Fig. 3.
It will be seen therefore, that these rings being fastened to the axle they will
turn with it independent of the hub of the wheel.
There are pinions 11 which are journalled on pins 10, said pinions being located
between the rings 7 and 8, and are in line and mesh with the pinion 2, on the hub
of the wheel. The numeral 12 designates an annular or internal toothed wheel,
which is rigidly connected to the bicycle frame, and is encased by plates 13.
The pinions 11 mesh with the said annular wheel 12.
The numerals 14 and 15 designate cranks, which are fastened on the threaded
ends 6 of the axle, and have roller crank-pins 16. At 17 and 18 are shown pedal
levers, which are provided with pedals at their forward ends, and pivoted to exten-

page_text: sions of the frame 19, said pedal levers have longitudinal slots 20, which loosely
receive the roller crank-pins 16.
When the pedal levers are reciprocated vertically the axle is turned, owing to
the connection of the cranks with the said levers, and the said axle revolves for
wardly, as denoted by the arrow. The forward rotation of the axle causes the
rings 7 and 8 to turn therewith, as they are connected thereto, but, the pinions 11
being in mesh with the annular or internal toothed wheel 12 are made to rotate,
and said pinions, by their engagement with pinion 2 cause the said pinion 2 to
revolve forwardly, thereby rotating the hub and wheel to which it is attached in
the same direction.
The direction of rotation of the various parts is shown by arrows; the stroke of
the pedal levers may be slow, and yet, owing to the multiplying gear, fast speed
can be obtained.
In view of the fact that both hub and axle turn forwardly, the friction will be
reduced a considerable degree.
The casing inclosing the parts on both sides protect the same from dust.
It is obvious that, the mechanism being located on the axle of the wheel; adapts
it to be used on almost any shape of bicycle frame, and the power being so con-
centrated will enable the frame of the bicycle to be made very light, the weight
of the rider only having to be provided for. Further advantages of the invention
are apparent, and therefore, need not be enumerated.
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:
-
In a bicycle gearing, the combination with a rotatable axle, of cranks connected
thereto, pivoted pedal-levers having slots adapted to receive the free ends of cranks,
a rotatable wheel-hub having a pinion, a stationary internal toothed gear rim, and
pinions carried by the axle and engaging with the gear rim and the pinion of the
hub, all substantially as set forth.
2. In a bicycle gearing, the combination with a rotatable axle, of cranks secured
thereto and having roller wrist-pins, pivoted pedal-levers having slots which
loosely receive said pins, rings secured to said axle, screws fastening the said rings
together, also pins and pinions journalled thereon, a stationary internal toothed
gear with which the said pinions mesh, a wheel hub rotatable independent of the
axle, and a pinion carried by the said hub which engages with the aforesaid
pinions, substantially as and for the purposes specified.
3. In a bicycle gearing, the combination with a bicycle frame, of a rotatable
axle having screw-threaded ends, balls interposed between the axle and the frame,
cranks secured and keyed on said ends, and having roller wrist-pins, pivoted pedal-
levers having slots which loosely receive the pins, rings, one of which is connected
by arms to one of the ends of axle and fastened thereto, screws and pins connect-
ing said rings together, pinions journalled loosely on pins and located between the
rings, a rotatable hub having a pinion that is in line and meshing with the afore-
said pinions, balls interposed between said hub and the axle, a stationary internal
toothed rim in mesh with the pinions carried by the rings, and casing plates
located on opposite sides of said internal toothed rim and secured thereto, all sub-
stantially as and for the purposes set forth.
W. G. TRETHEWEY,
Vancouver, B.C., Agent.