Improvements in or relating to Change Speed Gear and Brake Mechanism for Cycles.
Year: 1899

page_text: Date of Application, 17th Oct., 1899-Accepted, 25th Nov., 1899
Improvements in or relating to Change Speed Gear and Brake
Mechanism for Cycles.
A communication from Doctor LEON STILMANT, of Brussels, in Belgium.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of London,
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 ascer-
tained in and by the following statement:
-
The present invention relates to change speed gears for bicycles, tandems,
tricycles and the like, and has for its special object
1. To change at will the speed of the machine during travelling.
2. To allow the rider to keep his feet stationary on the pedals when the machine
has acquired a desired speed; and
3. 10 actuate, by means of the pedals, a brake adapted to press progressively
and with great power against one of the road wheels, and arranged in such a
manner that the maximum pressure, resulting in the instantaneous stopping of
the machine, is produced at the moment the cyclist descends from his machine
by using one of the pedals as a step. The whole of the device can be adapted to
any velocipede, whether driven by means of a chain, or without it, i.e. in the so-
called chainless cycles, and its application requires no change in the form of the
frame, and finally part of it can also be applied to machines which are provided
for one speed only, for the purpose of securing a free wheel or independence of
the pedal and the toothed wheel, and for applying the brake.
The device when applied to a cycle does not affect the symmetry of the machine,
on the contrary the lines become more symmetrical, especially in chainless cycles,
in which the change of speed is preferably obtained by the difference of the ratio
between the gear wheels of the rear driving wheel of the machine. The results
claimed for this invention are obtained by doubling, in any kind of cycle driven
by chain or otherwise, the parts transmitting the force, in other words, by pro-
viding the machine on both sides with similar means of transmission to those
generally placed on the right side only, with the difference however, that on one
side there will be arranged a speed-gear higher than that of the other side.
Besides this, it is necessary that the toothed wheel of the high speed gear should
be loose on the pedal axle, while the wheel actuating the low speed device is
fixed on the axle as in ordinary cycles, and that on the other hand, the pinion
of the high speed gear should be fixed on the hub of the driving wheel of the
machine, while the pinion of the low speed gear is loose on the same hub, in
the direction opposite to the ordinary forward movement of the machine, in such
a manner that the driving wheel cannot gear with the small speed gear as long as
its velocity is greater than that transmitted to the pinion of the low speed gear
by the corresponding actuating toothed wheel.
It follows from the preceding that to be able to travel at will by means of one
or other speed gear, or to have the pedals inactive while the machine is moving
forward owing to the momentum acquired, it is sufficient that the wheel of the
high speed gear should be so arranged as to be able to be connected to or dis-
connected from the corresponding crank whenever required.
For this purpose the crank corresponding to the high speed gear is provided with
a movable latch on one of its sides, which can be engaged in or disengaged from
a recess in a circular plate secured to the toothed wheel of the high speed gear.

page_text: The coupling of the latch, effected by a small lateral movement of the foot,
and the uncoupling of the same effected by the pressure of the feet on the pedals
in a direction contrary to the movement of the cycle, produces the connection
and disconnection respectively of the toothed wheel of the high speed gear, which
enables the rider to use either the high speed pear, or the low gear, or to stop
the pedals from rotating, the hub of the driving wheel being loose in the first and
last case as regards the pinion of the low speed gear.
The decrease of speed and the final stoppage of the machine is obtained by
means of a brake acting on the back wheel, and arranged at the end of a lever
articulated to the frame of the machine and actuated by a forked lever arranged
on the wheel of the low speed gear, when the machine is provided with two speed
gears, or on a crank if the machine is arranged for one speed only, the action of
the second lever on the brake lever being produced by back pedalling.
In the accompanying drawings the invention is represented by way of example
as applied to a machine showing the speed gear device with the brake apparatus.
Figure 1 represents in a front view the speed gear coupling device, as applied
to a machine driven by chain, the drawing showing the pinion in the coupled
position.
Figure 2 represents the same, but in the uncoupled position.
Figure 3 is a longitudinal section on the line V-x of Figure 1.
Figure 4 is a cross section of the crank on the line Y-Z of Figures 1 and 3.
Figure 5 is an elevation of the brake and its actuating mechanism, while
Figure 6 represents the same in plan.
The coupling and uncoupling device represented in Figures 1, 2, 3 and
consists principally of a metallic part 1 curved and fixed to the arms or spokes
of the toothed wheel 2 of the high speed gear, which is independent of the pedal
axle 3.
This part 1 is provided on its periphery with a recess 5 the front side of which
as regards the direction of movement of the machine is approximately radial,
while the other side is inclined, and terminates outwardly with a projection 7
forming a kind of cam or eccentric on the periphery of the part 1.
Into this recess 5 a latch 6 is adapted to enter the point of which is so shaped
as to fit the recess-5, the said latch being arranged on the inner side of the crank 8,
where it is guided in its movement by a plate 9 attached to the crank in any
suitable manner.
The latch 6 is normally drawn towards the crank axle by two springs 10
fixed at one end to the crank and suitably connected at the other end to the
latch say by means of a pin 11.
The latch is also provided with a flat spring 12 the end of which is provided
with a pin 13, which when the latch is not locked keeps it in its unlocked position
by entering a recess or hole 14 in the crank, as represented by the dotted lines
in Figures 2 and 3. This hole also receives another pin 15 fixed to the free end
of another flat spring 16 fixed on the outer side of the crank, and which is
intended to drive out the pin 13 from the hole for the purpose of effecting the
coupling of the wheel.
In order to diminish the friction which otherwise would take place during the
time that the wheel is not keyed, between the toothed wheel 2 and the crank
axle 3, these two parts are provided with ball bearings, comprising a disc 4
fixed on the axle 3, or made in one piece with it. The disc 4 is provided with a
groove, on which the inner rim 18 of the wheel 2 revolves. Any lateral displace-
ment of the latter is prevented by the two side plates 19, which at the same time
serves as dust guards.
Balls 17 are introduced into the recess of the disc 4 through a hole provided for
that purpose in the crown 18, and closed afterwards in any suitable manner. The
toothed wheel 2 being uncoupled, i.e., the latch 6 occupying the position repre-
sented in Fig. 2 all the cyclist has to do to produce an engagement is to slightly

page_text: move his foot laterally on the pedal at the moment when the latter occupies its
lower dead point in such a manner as to press against the spring 16, the pin 15 of
which will then completely pass through the perforation 14, and press out the
pin 13 of the spring 12, whereupon the latch will be free to follow the action of
the springs 10 owing to which it will slide along the part 1 until it arrives at the
recess 5 into which it will engage. From this moment the wheel 2 of the high
speed gear is coupled with the crank 8 and produces the corresponding movement
in the machine.
In order to uncouple the wheel 2, the cyclist must press down the pedal, so as
to render it immovable when it arrives at its lower dead point, while the wheel
still moves forward owing to the momentum acquired by the machine. The con-
sequence of it will be that the inclined face of the recess 5 will be forced over the
latch 6 i.e., force it out of the recess and over the eccentric or cam 7. The object
of the latter is to produce a sufficient downward displacement of the latch so that
the pin 13 may enter the hole 14, and that during the rotation of the wheel the
latch should not be in frictional contact with the periphery of the part 1 (see
Figure 2).
The latch 6 being now free from the recess 5 the pedal will move independently
of the wheel 2, and the cyclist may now go forward either by means of the low
speed gear, or rest his feet on the stationary pedals and move along slowly owing
to the momentum acquired by the machine.
The brake represented in Figs. 5 and 6 consists of a lever 23 pivoted on the
wheel 34, the free end of which lever is fork-shaped and embraces a pin 30
arranged at the end of a lever 24 mounted loosely on an axle 27 suspended from
a collar 28 mounted on a cross bar 29 on the horizontal back fork of the frame.
The axle 27 is also provided with a forked lever 25, at the end of which is
mounted a brake 26 of any form or shape, but preferably in the form of a roller,
so as to diminish the wear and tear of the tyre of the wheel.
The brake works in the following manner:-
When the cyclist wishes to decrease his pace or to stop the machine altogether
he first uncouples the high speed gear and presses upon the pedal of the crank 21,
as it rises and arrives near its horizontal position.
The toothed wheel 34 of the low speed gear then becomes driven in the opposite
direction to its ordinary direction of rotation, but the machine continues to move
onwards since the high speed gear is uncoupled and the pinion of the low speed
gear is loose on the hub of the driving wheel of the machine.
Owing to the back pedalling and the reverse rotation of the wheel 34 the fork
of the lever 23 acts upon the pin of the lever 24 and causes it to move downwards
as represented by the arrow in Figure 5. The lever 25 being mounted on the
same axle 27 as the lever 24 will therefore be affected by said movement, and owing
to the brake 26 will rise and press against the tyre of the wheel.
This action of the brake is progressive and acquires its maximum force when
the brake has described about of a revolution in the direction of the arrow 22,
and has arrived at its lower dead point. At this moment the cyclist may dismount
from the machine making use of the pedal as a step, thereby bringing his whole
weight upon it, with the result that the machine will be instantaneously stopped.
In case the machine is provided with only one speed gear the toothed wheel
of which is provided with the coupling device, the brake will be operated directly.
by the crank and for this purpose the lever 23 will be pivotted upon it.
When the machine is provided with a two-speed gear it is advisable to apply
to the chain of the low speed gear a jockey pulley 32, supported on an adjustable
arm 31 connected with the frame of the machine in any suitable manner (see
Figures 5 and 6).
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent and in what
manner the same is to be performed, I declare that what I claim is :-
1. A device for changing the speed, during travelling, of cycles and the like

page_text: comprising two driving chain or other gears of different speeds arranged on
opposite sides of the machine.
2. In a device of the kind described for changing the speed of cycles and the like
during travelling comprising a toothed wheel of the high speed gear loosely
mounted on the crank axle, but capable of being coupled with and uncoupled
from the crank, the pinion of the high speed gear being fixed on the hub of the
driving wheel of the machine, the toothed wheel of the low speed gear fixed
on the crank axle, and the pinion of the low speed gear mounted so as to be, free
in the direction of rotation opposite to that of the driving wheel so as to permit
of travelling with the low speed gear or of keeping the pedals stationary when
the high speed gear is uncoupled substantially as described.
8. In a device of the kind described for changing the speed of cycles and the
like during travelling an actuating mechanism for the high speed gear comprising
a toothed wheel provided with a coupling device and a crank provided with a
latch and means for holding the latch in its extreme positions when required
substantially as described.
4. In a device of the kind described for changing the speed of cycles and the
like during travelling a wheel actuating the high speed gearing mounted loosely
on the crank axle on the outer face of which is a curved coupling part provided
with a recess adapted to receive a latch for the purpose of connecting the wheel
with the crank, and a cam or eccentric forming a projection on the periphery of
the curved part for the purpose of pressing out the latch to its extreme position
when uncoupling takes place substantially as described.
5. In a device of the kind described for changing the speed of cycles and the like
during travelling the combination of a wheel actuating the high speed gearing
provided with an inner grooved rim and a grooved disc mounted on the crank
axle and within said rim and balls arranged in the groove between said parts
for the purpose of diminishing friction substantially as described.
6. In a device of the kind described for changing the speed of cycles and the
like during travelling a crank provided with a latch and actuating springs for
the purpose of effecting the coupling of the latch with the actuating wheel a spring
plate attached to the latch and provided with a pin adapted to enter a transverse
hole in the crank for the purpose of holding in position the said latch and a spring
mounted on the crank and provided with a pin for pressing out the latch from the
hole and thereby releasing the latch substantially as described.
7. The application of the device for coupling and uncoupling the toothed
driving wheel, to cycles having only one speed gear for the purpose of being able
to travel with stationary pedals substantially as described.
8. The combination with a change speed gear of the kind described of a brake
device comprising a pivoted lever secured to the low speed wheel, which lever
on back pedalling actuates a lever suitably mounted and provided with a brake
for the purpose of applying the latter progressively and energetically against the
tyre of the wheel when the rider presses downwards on the rising pedal of the low
speed gear substantially as described.
9. The application of a brake device of the kind described to a cycle provided
with only one speed gear having a device for coupling and uncoupling sub-
stantially as described.
10. The complete change speed gear for cycles and the like substantially as
described or illustrated in the accompanying drawings.
Dated this 17th day of October 1899
BOULT, WADE & KILBURN,
Agents for the Applicant.