Improvements in and relating to Velocipedes.
Year: 1892

page_text: Date of Application, 15th Nov., 1892-Accepted, 21st Jan., 1893
COMPLETE SPECIFICATION.
Improvements in and relating to Velocipedes.
I, DESIRE FELIX MÉGRET, of 2, Boulevard de Strasbourg, Paris, in the
Republic of France, Manufacturer, 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 velocipedes and comprises a differential mechanism for
transmitting the motion of the pedals to the driving wheel of such vehicles. It has
for its object to dispense with the endless chain ordinarily used and to enable the
velocipede to be driven at will either at a small or at a great speed; and it permits
of the pedals being left free downhill when the machine can move by the speed
acquired.
In the accompanying drawing
Figure 1 is sectional elevation of a bicycle showing my improved transmitting
gear for two speeds.
Figure 2 shows a side view of the bicycle.
Figure 3 is a vertical section through the axis of the nave of the driving wheel.
The cranks a a¹ of the pedals are keyed upon the axle 6 of the driving wheel of
the bicycle. This axle 6 has fixed upon it the toothed wheels ce and the parts d d¹
which are screwed upon screw-threaded parts 6' 6 of the axle.
C
The parts d d form supports with balls for the terminal boxes of the nave e of
Shoulders e e² of the
the wheel, which nave is loosely fitted upon the axle b.
nave serve for fixing the ends of the spokes r of the wheel by means of screw
threads. On the outside of the terminal boxes of the nave are fixed toothed
wheels g g'.
:
The toothed wheels c c' on the axle actuate two circles of rollers hh'; the support
for one circle of rollers is made in one piece with that for another circle of rollers k,
and the support for the second circle of rollers with that for the circle of rollers k
The circles of rollers hk, kroll loosely, with interposition of balls, upon and
between the parts ll, m m³ which are fixed by screw threads upon the screw-
threaded axes o o', counter nuts 'n'n' being provided to prevent the unscrewing of
the nuts m m³.
The axes o o¹ form one piece with the shoulders ppl which are fitted in
recesses in the boxes ss carrying two ball bearings in which the axle b
turns, and attached to the branches of the fork t t of the velocipede.
y
}
As shown in the drawing, the axes o o' are made eccentric relatively to the
"shoulders p'p'; the latter are designed to turn in their place in order to lower or
raise the axes o o relatively to the axis of the axle; that is to say in order to
cause the circles of rollers hk and h¹¹ to engage with or disengage from the
toothed wheels cg and c¹ g', the, former two wheels belonging to the axle and the
latter two wheels to the nave.
This eccentric. movement of the axes o o' is produced as follows:
Upon the prolongation of the shoulders p p are fixed two pinions with which
gear two racks which can be actuated by the aid of a handle y pivoted at t' and
connected to these racks by arms and the long rods u u¹ u².
By raising the handle y the racks ..c' are raised, but as the eccentricities of the
axes o o' are diametrically opposite the result is that the two circles of rollers lik
are raised while the two circles of rollers are lowered.
لم
It may be observed that these circles of rollers hk, h¹ k¹ are raised or lowered a
somewhat greater distance than two lengths of a tooth of the pinions cg, c¹ g¹, so
that by placing the handle y in its middle position the circles of rollers and toothed

page_text: wheels are all disengaged and the driving wheel can move loosely without turning
the pedals.
To the different positions which the handle y must occupy correspond three
notches provided on a sector y¹. A spring bolt carried by the handle y engages
with one of these three notches for keeping it therein.
For the handle y may be substituted a hand wheel adapted to turn in front of a
scale indicating the relative positions of the mechanisms the operation of which is
'hereinafter set forth.
"
Suppose the several parts occupy the positions indicated in the drawing, it will
be seen that the left hand toothed wheel c belonging to the axis of the pedals does
not gear with the circle of rollers h; in like mauner the circle of rollers k does not
come in contact with the toothed wheel 9 on the nave e of the driving wheel. But
on the right hand side the toothed wheel c¹ operates the circle of rollers ¹ and
the circle of rollers k¹ operates the toothed wheel g' on the nave. In this case the
pedals actuate the velocipede through the intervention of the gearing on the right
hand side.
For utilizing the gearing on the left hand side the handle y is lifted for raising
the racks xx so that the rack ¹ will cause the axis o'p' to turn sufficiently for
disengaging the circle of rollers from the wheels c'g'. At the same time the
rack turns the pinion and with it the axis op; this partial rotation causes the
circle of rollers hk to engage with the toothed wheels cg, and the pedals will then
operate the bicycle by the mechanism on the left hand side.
By this mechanism on the left hand side the bicycle can be driven at a speed
which may for example be in the proportion of 1 to 2 to the velocity of the pedals;
whilst in the case of the mechanism on the right hand side the proportion may be 1
to 1.5.
When the mechanisms on the right and left are in their disengaged position the
pedals are loose and may remain immovable. This position can be utilized downhill
when the machine has been started and has acquired a sufficient speed.
By the use of the above-mentioned circles of rollers hk h¹¹ the engaging and
disengaging operations can be effected with facility, and they have the further
advantage of reducing the friction, but toothed wheels may be substituted for
them.
The brake is adapted to act upon the rear wheel. It is operated by means of a
..lever pivoted at w³ and connected by a rod w³ to a bell-crank-lever w which is
united with a lever wo by means of a rod to. The lever w³ acts upon the brake
pad to to which it is attached.
The mechanisms. on the right and left are enclosed in tightly closed boxes in
order to permit of an abundant and automatic lubrication with oil. The tight
joints of the boxes protect the parts against dust.
It may be observed that the two engaging and disengaging mechanisms may
be arranged at one end of the axle of the driving wheel instead of one being
mounted on the right and the other on the left as I have supposed. But in
both cases the system is essentially characterized by the eccentric displacement of
the intermediate gearing.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
First. In velocipedes the arrangement of mechanisms independently of each
other either at the two ends or at one end of the axle of the driving wheel,
with engaging and disengaging movements caused by a simple operation or by
distinct operations for displacing the intermediary parts eccentrically, such
mechanisms enabling the velocipede to be driven at two different speeds and the
action of the pedals to be stopped substantially as herein specified and represented
in the drawing.
Second. In velocipedes having engaging and disengaging mechanisms applied

page_text: to the driving wheel as described in the first claim the eccentric displacement
of the intermediary gearing, such as the circles of rollers or toothed wheels hk h¹k¹,
by means of racks which are raised or lowered simultaneously and act upon
gear wheels g g¹ keyed at a right angle, in such a manner that when the inter-
mediary circles of rollers or toothed wheels transmit the movement of the
pedal a¹ and of its toothed wheel c' to the driving wheel by means of the toothed
wheel the intermediary circles of rollers or toothed wheels h and kare
disengaged from the toothed wheels cg, and that when the intermediary circles
of rollers or toothed wheels hk hk are disengaged respectively from the toothed
wheels cg cg the pedals are loose and will not act, substantially as herein
described and for the purpose specified.
Third. In velocipedes the application of the brake to the rear wheel by the
devices herein described, either in or not in combination with the engaging and
disengaging mechanisms specified.
Dated this 15th day of November 1902
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.