Improvements in or relating to Driving and Braking Mechanism, particularly applicable to Motor Vehicles.
Year: 1898

page_text: Date of Application, 30th Dec., 1888
Complete Specification Left, 26th Sept, 1899-Accepted, 25th Nov., 1899
Improvements in or relating to Driving and Braking Mechanism,
particularly applicable to Motor Vehicles.
A communication from A DARRACQ & Co., Engineers, of Paris, in the Republic
of France
I, ALFRED JULIUS BOULT, of 111, Hatton Gaiden, in the County of London,
Chartered Patent Agent, do hereby declare the nature of this invention to be
as follows:-
1
This invention relates to improvements in diving and braking mechanism and
is particularly applicable to motor vehicles, and will be described with reference
thereto.
Motion is transmitted from the diving shaft to the diven shaft which 18
in two parts connected by differential gear-by means of a toothed wheel of
said gear which is constructed in a manner hereinafter to be described Two
toothed wheels of different size are arranged to engage with this main wheel
according to the speed of rotation desired These wheels are respectively
mounted on opposite ends of a bar oscillating about a spindle to which are
keyed two toothed wheels, a wheel driven by the driving shaft by means of a
toothed wheel keyed to the latter shaft, and another wheel engaging on the
one hand directly with one of the intermediate wheels and on the other hand
with a wheel driving the other intermediate wheel on the spindle of which it
18 keyed.
Fixed stops respectively corresponding to the heads of the lever limit the
oscillation of the latter in the two duections corresponding to the engagement
of one of the intermediate wheels with the main wheel, in accordance with the
speed desired
The lever is operated by means of a 1od and an adjustable 10d which 18
operated by pulling or pushing and which is fixed in an invariable position
with relation to that of the toothed wheels giving the desired speed, by means
of a device constituted by a handle extending beyond the desned point in the
two extreme positions
The parts of the gear described as well as the spindles, coupling, differential
gear and chain pinion connected to the latter, in case the device is applied to
a tricycle or quad cycle and has a pedalling gear, are all preferably enclosed
into a casing provided with the necessary projections and accessories in order
suitably to support all the different paits
As regards more particularly the chain pinion used for cars comprising a
pedalling gear, the corresponding portion of the casing surrounds it very closely
thereby preventing the chain fiom coming off in a radial direction In order
to enable the chain to be casily put on and taken off the pinion without dis-
turbing the casing or the gear, a portion of said casing is provided at a suitable
point, exactly corresponding to the high top of the teeth of said pinion with an
opening enabling the end link of the chain to pass through and to engage with
the corresponding tooth of the pinion so that simply by 1otating the latter,

page_text: the engagement of the chain is effected, as the chain is surrounded closely by
the casing and cannot come off from the teeth of said pinion in a indial direction
The chain pinion is connected to the differential gear by a pawl gear with
1ollers acting in well known mannor, so that said differential gear receiving the
driving action alone the pinion and its chain consequently are not rotated,
whereas by acting by pedals either to aid the motor on to start the car, the
engagement of said pinion with the differential goar 18 eftected, so as to act
on the latter
As already stated, the pinion is used only for motor cars provided with
pedalling geal, such as tricycles, quadricycles, etc When the diving gear
is to be used to load cariages, the pinion is done away with and replaced by
a socket serving only to fill up the empty space formed by the removal of the
pinion and to ensure the connection and support of different parts of the
mechanism.
-
Be-
The construction of the main wheel of the differential gear is
as fol-
lows:
A portion of said wheel is provided with a projection and a side flange
combined with the side of the other part of the differential gear, on which the
brake band acts the construction of which will be herematier described
tween these sides 18 supported over the projection a ring of a slightly less width
than the distance between the sides so as to enable it to move to a perceptible
extent between said sides. Said 11ng is caused to participate in the rotation of
the annular part by projections arranged on its surface so as to engage with
corresponding recesses made in the external surface of the side of the annular
pait allowing all the slight displacement of the ring between the sides to take
place freely.
The inner edge of the 1ng fits over the projection, its outer surface being
conical and receiving an outer ring, conical internally and provided outside
with teeth, said ng tiansmitting the movement by means of one of the other of the
intermediate wheels referred to according to the speed desired.
The 11ng 18 combined with helical spings arranged in its corresponding
recesses and resting the one side against the inner face of the side of Hange
and on the other side against the bottom of the recesses e against the ring
itself The springs thus have the tendency to push the ring in the direction
adapted to produce the wedging of the conical sui faces by means of which the
outer ring is connected to the differential gear.
The force of the spings is calculated so as to correspond exactly to the tan-
gential maximum effort of the motor, so that with the given combination of the
iings with the springs, there will be a normal driving of the inner ring and,
consequently, of the differential gear, as long as the resistance to this driving
effort does not exceed the maximum tangential effort of the motor. It in con-
sequence either of too sudden throwing into gear or any other reason, said
resistance exceeds the maximum tangential effort of the motor, the resistance
of the springs will be overcome, the result being that the outer ring or crown
will slide on the inner ring, that is to say, only the teeth will be driven by the
motor, the wedging of the cones being prevented by the ing sliding in the
corresponding direction between the sides
This construction of the toothed wheel mechanism gives the great advantage
of doing away with any appreciable shocks adapted to break toothed wheels or
other parts during the driving or throwing into or out of gear of the parts
The biake acts as already stated on the cylindrical portion of the differential
gear and is constituted by a band centred outside, in the position of rest within
an annular projection of the casing, partially surrounding at a suitable distance
the cylindrical part of the differential gear, said band having its fixed end con-
neoted to the corresponding end of the annular projection, whereas the movable
or fice end, by means of which its tightening is effected is connected to a rod
operated from any suitable point of the car.

page_text: Owing to the arrangement of the band centred outside in the position of rest
as described, any friction of said band on the differential gear when the brake
is inoperative, 18 avoided, a loss of power caused by such friction in all the other
band brakes being thus avoided.
It will be understood from the description of this driving gear, that the pro-
portion between the transmission wheels can be easily altered according to the
gear to be obtained The proportions between the wheels for changing speed
may be also chosen to obtain the desired speed of rotation.
Modified constructions comprise. a casing enclosing parts of the driving gear,
so as to be easily and conveniently opened for inspection or repairs of the parts,
and a device for operating the brake band simply by back pedalling on the
pedala usually serving for starting
The improved casing 18 in two parts The lower part is secured in the usual
manner to the corresponding part of the frame the upper part fitting on to the
lower one and is connected to it by bolts so as to render it readily detachable
In order to open the casing, it is thus sufficient to unscrew the bolts connecting
the two parts, whereupon the upper part can be removed, the lower part remain-
ing secured to the frame
The operating of the band brake by foot is effected in the following manner:—
With the chain pinion provided with the ratchet gear which is operative
during the forward movement under ordinary conditions, is combined another
atchet gear arranged to act in the opposite direction to that of the first ratchet
gear also by the pedals, but only when rotated backwards.
The outer surface of this ratchet gear is provided with teeth with which
engages a toothed sector mounted on a pin oscillating in a bracket provided in
a desired position on the upper part of the casing. A shackle on the hub of
the sector has hinged or pivotted to it the end of a rod operating the brake,
the other end of said 1od being connected to the free end of said brake
The function of the first ratchet gear coupling remaining the same for starting
or helping the motor by operating the pedals in the forward direction, it will
be sufficient, in order to apply the brake, to begin back pedalling, whereupon
by means of the toothed ring and sector action is exercised on the rod in the
direction to cause the application of the brake
As soon as back pedalling ceases, the braking also ceases and the feet remain
at rest on the pedala during the movement of the motor in the usual manner
or they may exercise an action in the forward direction The two ratchet gears
art absolutely independently of each other
Dated this 30th day of December 1898
BOULT & WADE,
Agents for the Applicant
Improvements in or relating to Driving and Braking Mechanism,
particularly applicable to Motor Vehicles.
A conmunication from A. DARRACQ & Co., Engineers, of Paris, in the Republic
of France
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
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
ascertained in and by the following statement.-
This invention relates to improvements in driving and braking mechanism and

page_text: 18 particularly applicable to motor vehicles and is represented by way of example
in the accompanying drawings in which.-
Figure 1 shows a geal according to this invention in longitudinal sectional
elevation Figs 1* & 1 are detail views on an enlarged scale of paits shown
in Fig 1
Figure 2 18 a side elevation
Figures 3, 4 and 5 show details of modified parts, Figure 3 being an external
transverse clevation with paits removed
Figure 4 a plan, also with parts removed and
Figure 5 a partial vertical section of Figure 3
With reference to Figures 1 and 2
It
Motion is transmitted from the diving shaft A to the driven shaft B which
18 in two parts connected by differential gear U by means of a toothed wheel D
of said gear which is constructed in a manner hereinafter to be described
will be seen by examining Figure 2 that two toothed wheels EE of different
size are arranged to engage with this main wheel D according to the speed of
1otation desired These wheels are respectively mounted on opposite ends of a
bar or carrier F oscillating about a spindle Fl to which are keyed two toothed
wheels, a wheel G driven by a pinion G¹ kered on the driving shaft and another
wheel Hengaging on the one hand directly with the wheel E and on the other
hand with an intermediate wheel H¹ for 1otating the wheel E¹ on the spindle of
which it is keyed
Fixed stops II¹ respectively corresponding to the heads JJ of the carrier F
limit the oscillation of the latter in the two directions corresponding to the
engagement of one of wheels E o E with the wheel D in accordance with the
speed desired
The caner F is operated by means of a level K and an adjustable tod K' which
18 operated by pulling or pushing and which is fixed in position corresponding
to that of the toothed wheels giving the desued speed, by means of a device
constituted by a handle extending beyond the dead point in the two extreme
positions
In Figure 2 the proportion between the wheels E E¹ being given the driven
shaft is rotated at high speed If the wheel E' instead of E were in engagement
with the wheel D the speed would be lower
The parts of the gear described as well as their spindles, coupling, differential
gear and chain pinion L connected to the latter, in case the device is applied
to a cycle and has a pedalling gear are all preferably enclosed in a casing L¹
provided with the necessary projections and accessories in order suitably to
support all the different parts.
In
As regards more particularly the chain pinion L used for vehicles comprising
a pedalling gear, the corresponding portion L" of the casing surrounds it very
closely thereby preventing the chain from coming off in a radial direction
order to enable the chain to be easily put on and taken off the pinion L without
disturbing the casing or the gear, the portion L" of said casing L' 18 provided
at a suitable point exactly corresponding to the top of the teeth of said pinion L
with an opening M enabling the end link of the chain to pass through and to
engage with the corresponding tooth of the pinion L so that simply by rotating
the latter, the engagement of the chain is effected as the chain is surrounded
closely by the casing and cannot come off from the teeth of said pinion Lin
a radial direction
The chain pinion L is connected to the differential gear by a pawl gear M'
with rollers acting in well known manner so that said differential geal receiving
the driving action alone the pinion L and its chain are not notated whereas
by rotating the pedals either to aid the motor or to start the car the engagement
of said pinion L with the differential gear is effected so as to act on the latter
As already stated, the pinion L is used only for vehicles provided with pedal-
ling gear, such as, tricycles, quadricycles etc When the driving gear is to be

page_text: used for road carriages, the pinion is done away with and replaced by a socket M",
(Fig. 1) serving only to fill up the empty space formed by the removal of the
pinion L and to ensure the connection and supports of different parts of the
mechanism
-
The construction of the wheel D of the differential gear is as follows
The portion D¹ of said wheel 18 provided with a projection D and a side
or flange N combined with the side N' of the other part Nu of the differential
gear on which a brake band O acts the construction of which will be herein-
after described Between these sides N N 18 supported over the projection D"
a ring 0¹ of a slightly less width than the distance between the sides N N¹ so
as to enable it to move to an appreciable extent between said sides N N¹ Said
ring is caused to participate in the rotation of the part D¹ by projections O
(Figs 1ª & 1º) arranged on its surface so as to engage with corresponding
recesses P in the external surface of the side N of the part D₁ allowing all the
slight displacement of the ring 0' between the sides N N to take place freely
The inner edge of the ring O' fits over the projection D its outer surface P¹
being conical and receiving a ling conical internally and provided outside
with teeth Q said ring Q transmitting the movement by means of one or the
other of the wheels EE according to the speed desned
The ring 01 is provided with helical springs R arranged in its corresponding
recess R¹ and resting at one end on the inner face of the side or flange N and
on the other end against the bottom of the recess R¹, e, against the ring 0¹
itself The springs thus have a tendency to push the ring in the direction
adapted to produce the wedging of the conical surfaces P¹ P" by means of which
the ring Qis connected to the part D¹ that is to say to the differential gear
The force of the springs R is calculated so as to correspond exactly to the
tangential maximum effort of the motor, so that with the given combination of
the rings Q and O' with the springs R there will be a normal driving of the
ring O and, consequently, of the differential gear, as long as the resistance to
this driving effort does not exceed the maximum tangential effort of the motor
If in consequence either of too sudden throwing into gear or any other reason,
said resistance exceeds the maximum tangential effort of the motor, the resis-
tance of the springs R will be overcome, the result being that the ring o
crown Qwill slide on the ring 01 that is to say only the toothed ring Q₁ will
be driven by the motor, the wedging of the cones P1 P being prevented by the
ring sliding in the corresponding duection between the sides N and N'
This construction of the toothed wheel mechanism gives the great advantage
of doing away with any appreciable shocks adapted to break toothed wheels or
other parts during the diving or throwing into or out of gear of the parts
The brake acts as already stated on the cylindrical portion N of the differential
gear and is constituted by a band centered outside, in the position of reat,
within an annular projection S of the casing, partially surrounding at a suitable
distance the part N said band O having its fixed end S¹ connected to the cor-
responding end of the projection S, whereas the movable or free end Su by means
of which its tightening is effected on the part N 18 connected to a lever T
or the like operated from any suitable part of the vehicle
Owing to the arrangement of the band O centered outside in the position of
rest as described, any friction of said band on the part Nu, when the brake 18
inoperative, is avoided, a loss of power caused by such friction in all the other
band brakes being thus avoided
It will be understood from the description of this driving gear, that the
proportion between the wheels GG can be easily altered according to the gear
to be obtained The proportions between the wheels for changing speed may
be also chosen to obtain the desired speed of rotation
With reference to Figures 3, 4 and it will be seen that as compared to the
construction shown in Figures 1 and 2, the improved or modified construction
shown in Figures 3, 4 and 5 comprises a casing enclosing parts of the driving

page_text: geal so as to be easily and conveniently opened for inspection or repair of
the parts, and a device for operating the brake band simply by back-pedalling
(on the pedals usually used for starting).
It will be readily seen from Figures 3 and 4, that the improved casing is
in two parts The lower part A¹ is secured in the ordinary manner to the cor-
esponding part of the fiame B', the upper part fitting on to the lower
part and connected to it by bolts arranged at D'E³ F³ G³ H³I' so as to render
it readily detachable
In order to open the casing, it is thus sufficient to unscrew the bolts con-
necting the two parts. whereupon the upper part ¹ can be removed, the lower
part A remaining secured to the frame
The operating of the band biake by foot is effected in the following manner.
With the chain pinion L provided with a ratchet gear M¹ which is operative
during the forward movement under ordinary conditions (Figs 1 and 2), 18
combined another ratchet gear M³ arranged to act in the opposite direction to
that of the first ratchet gear M, also by the pedals, but only when rotated
backwards.
The outer surface of this ratchet gear is provided with teeth M* with which
engages a toothed sector mounted on a pin M6 in a bracket or beaung M7
provided in desired position on the upper part C₁ of the casing A part N¹ on
the hub of the sector M has hinged oi pivotted to it at N the end of the 10d N5
operating the brake, the other end N of said rod being connected to the free
ond of said brake
The function of the first ratchet gear coupling M remaining the same for
starting or assisting the motor by operating the pedals in the forward direction,
it will be sufficient, in order to apply the brake, to begin back-pedalling, where-
upon by means of the toothed ring M and sector M action is exercised on the
rod No in the direction to cause the application of the brake
As soon as back pedalling ceases, the braking also ceases and the feet iemain
at rest on the pedals during the movement of the motor in the usual
manner, or they may exercise an action in the forward direction. The two
ratchet gears M' and M³ act absolutely independently of each other
Having now particularly described and ascertained the nature of the said
invention, as communicated to me by my foreign correspondents, and in what
manner the same is to be performed, I declare that what I claim is.
1 A speed gear diving mechanism comprising a driven toothed wheel of
a differential gear in combination with two different sized pinions arranged to
gear with the said wheel according to the speed desired, said pinions being
mounted at the ends of a 1od, bar or carrier mounted on an axle having keyed
on it two pinions, one of which is actuated from the driving shaft, while the
other engages both with one of the pinions on the carrier and with an inter-
mediate pinion actuating other pinions on the carrier, substantially as described.
2 In a speed gear driving mechanism of the kind described the arrangement
of a bar or carrier as F provided with two heads in combination with the fixed
stops II' whereby the oscillations of the carrier are limited in both directions,
a lever for operating said carrier and an adjustable 1od, connected to said lever
substantially as described
3 The aangement of a casing for the chain sprocket wheel in the case of
vehicles with pedal movement, with a plate surrounding the chain pinion closely
for the purpose of preventing the chain from slipping off the pinion, said casing
being also provided with an opening as m foi inserting or withdiawing the chain,
so as to be able to rapidly and easily put a chain in place or remove it sub-
stantially as described.
4 In a diving gear of the kind described the arrangement of a sleeve in
place of the sprocket wheel, which 18 omitted, when pedal gearing is not employed
said sleeve filling up the space rendered vacant by the removal or omission of

page_text: said pinion and assuring the connection and support of the different parts,
substantially as described.
5. In a driving gear of the kind described a toothed wheel as D provided
with a projection, as D, and side N, in combination with the other part, as N¹,
of the differential movement, actuated by a brake band, a ring surrounding the
projection D between the said sides and being slightly, movable between the
latter, while at the same time, involved in the rotation, by means of projections
upon it, with the annular part of the toothed wheel, the outer surface of the
ing being conical and combined with an outer ring with conical inner surface
and provided with teeth outside for effecting the transmission of movement,
the inner ring being provided with springs acting in such a manner as to press
the said ring so that its conical surface shall engage with that of the outer ring
and having its tension so calculated and arranged as to correspond with the
naximum tangential effort of the motor, substantially as described.
6 Biake mechanism acting on a cylindrical part of a differential geaning
comprising a band centered outside in the position of rest, and attached at one
end to a projection of the casing surrounding partly and at a suitable distance
the said cylindrical part, the said band having its other end fastened to an
operating rod worked from any suitable part of the vehicle substantially as
described.
7 A driving gear casing consisting of two parts the lower one as A' being
fixed to the frame or body of the vehicle, while the upper part can be adjusted
on the lower part. to which it is connected by bolts, substantially as described
8 The arrangement of parts for applying a brake by back pedalling com-
prising a ratchet gearing as M³, so disposed as to be actuated by back-pedalling
for the purpose of acting on a brake lever by means of a toothed ring and a
toothed sector, substantially as described
9 The complete speed gear mechanism substantially as described or illus-
trated in Figures 1 and 2 of the accompanying drawings
10. The complete brake apparatus for speed gear mechanism substantially as
described or illustrated in Figures 1 and 2, or in Figures 3, 4 and 5 of the
accompanying drawings.
Dated this 26th day of September 1800
BOULT & WADE,
Agents for the Applicant.