Apparatus for Changing the Speed Gear of a Bicycle Driving Wheel.
Year: 1895

page_text: Date of Application, 5th Dec., 1895
Complete Specification Left, 2nd Sept., 1896-Accepted, 3rd Oct., 1996
PROVISIONAL SPECIFICATION.
Apparatus for Changing the Speed Gear of a Bicycle Driving
Wheel.
I, EMILE VIARENGO, of 15 Place du Statut, Turin, Italy, Mechanic, do
bereby declare the nature of this invention to be as follows:-
:―
My invention relates to means of changing at will the speed gear of the driving
wheel of a bicycle. For this purpose, I fix on the pedal axle on each side of its
bearing a sprocket pinion, the one larger than the other, and on each side of the
driving wheel, but not fixed thereon, I provide a sprocket wheel the one smaller
than the other.
Both these wheels are connected by chains to the pinion on the pedal axle, and
both are free to revolve on balls held in grooves of a tubular axle which passes
through and is fixed in the nave of the driving wheel. Within this tubular axle,
(which, for convenience of fixing in the nave may be made in halves) is fitted an
internal axle free to slide therein, and having fixed in it a pair of transverse keys
which project through slots at opposite sides of the tubular axle, one outside each
of the sprocket wheels. The internal axle has fitted on its outwardly projecting
end a ring enclosing balls held in a groove of the axle, this ring being pivotted to
a forked lever which is mounted on the frame of the bicycle so that its upper end
is within reach of the hand of the rider. Each of the sprocket wheels has on its
outer face notches, to receive the transverse key adjacent to it. When the internal
axle is in its middle position neither of these keys is in a notch of the neighbouring
sprocket wheel, and both these wheels therefore revolve freely on the tubular axle ;
but when by means of the forked lever and ring the internal axle is slid the one
way or the other, the one or the other of the transverse keys engages notches in
the one or the other of the sprocket wheels, and the wheel thus engaged then
drives the driving wheel of the bicycle, the other sprocket wheel revolving
idly.
Thus by sliding the internal axle, the driving wheel may receive either of two
speeds or may be left free.
Dated this 5th day of December 1895..
ABEL & IMRAY,
Agents for the Applicant.
Apparatus for Changing the Speed Gear of a Bicycle Driving
Wheel.
I, EMILE VIARENGO of 15 Place du Statut, Turin, Italy, 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 means of changing at will the speed gear of the driving
wheel of a bicycle or other velocipede, as I will describe with reference to the

page_text: accompanying drawings, in which Fig. 1 shews a side view of a bicycle Fig. 2 an
enlarged sectional view of the driving gear, Fig. 3 a view of the handlever for
actuating the same, and Figs. 4 to 9 detached details. A is the tubular axle of
the driving wheel, the spokes of which are attached to the flanges m m. This axle
which is shewn detached at Fig. 4 is carried in ball bearings a a, shewn detached
at Fig. 5, and fixed to the fork n n of the bicycle frame.
On this axle are mounted two chain wheels cc which turn loose on balls. Within
the axle slides a rod B shewn detached at Fig. 6, to which are fixed two keys bb,
and which can be actuated by a hand lever D, so as to slide to and fro in the axle,
and thereby to cause the one or other of the keys b b, to engage with the lateral
slots formed in the projecting bosses of the chain wheels cc, these bosses being
formed in one with the central part c¹ of the wheel which is screwed into the other
part, as shewn detached at Fig. 7. By this means, either the one chain wheel or
the other is geared with the axle A, while the other ruus idle thereon. The pedal
shaft of the bicycle carries two chain wheels d d' of different diameters, which are
respectively geared to the wheels c c by pitch chains. When the rod B is moved
to the left hand at Figs. 1 and 2 by the hand lever D, the right hand wheel, will
be geared with the axle A, and this wheel being geared with the larger wheel d on
the pedal shaft, the bicycle will be driven at the quick speed. When the rod B is
pushed to the right hand, the left hand wheel c will be geared with the axle A, and
consequently the driving wheel will be driven at the slower speed by the chain
wheel d. Thus in moving the hand lever D to the notch marked 2 at Fig. 3, the
gear will be set at the quick speed, if it be set in the notch 1, the gear will be set at
the slow speed, and if the lever be set at the middle notch O, thereby bringing the
rod B in to the middle position shewn at Fig. 2 both chain wheels will, be out of
gear, and consequently the pedal shaft and pedals can remain stationary while the
bicycle is running.
The motion of the lever D is imparted by any suitable known transmitting
device to the fork e Figs. 1 and 8, which is connected to the rod B by means of a
ball bearing g, Figs. 2 and 9.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In apparatus for changing the speed gear of bicycles and other velocipedes,
the combination with a hollow axle A of a sliding rod B, sprocket wheels c c loose
on the axle and capable of being geared therewith by the motion of the rod B and
two sprocket wheels d d¹ of different diameters geared with the wheels cc by means
of two pitch chains, substantially as described.
2. In variable speed gear such as is referred to in the first claim, arranging the
rod B so that in the middle position thereof, both the wheels cc will be out of gear
with the axle, so that the pedals are stationary while the bicycle runs on,
substantially as described.
Dated this 2nd day of September 1896.
ABEL & IMRAY,
Agents for the Applicant.