appar
Year: 1885

page_text: I, PAUL ARTHUR GAMBARO, of N° 159 Rue Lafayette, Paris in the Republic of
France, Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements upon brake apparatus such as was
described in my previous Patent of 23rd Feb. 1884, N° 3834.
According to one of the present improvements, the helical brake band is made to
act upon a drum fixed on the axle of the wheels instead of on the wheels them-'
selves, the traction bar operating the same being discontinuous in form and
combined with traction springs. The boxes of the buffer and draw bar springs
contain discs bearing against a shoulder of the box and loose upon the buffer roda
and draw bar. The draw bar has a key or stud, which, when the bar is drawn
out, acts upon a ring on the bar which, after the latter has moved through a
certain distance, comes in contact with the said disc. During this first motion of
the draw bar, it acts in opposition to a helical spring connected to the framing
through the medium of diagonal acting links connected thereto by a compensating
bar. Owing to this resistance to the first motion of the draw bar no shock will be
experienced when the before mentioned disc is made to act upon the draw bar
spring. The diagonal links from the draw bar are connected to crank arms having
rollers that serve to tighten the brake band, and which bear against the drum on
the wheel axle, so that by the first pull of the draw bar, the crank arm is actuated
so as to remove the rollers from the drums, in which case the helical band on the
drum is not tightened, and the brakes are not applied. On the other hand, if the
draw-bar is not actuated, in being moved back to its original position by the
draw-bar spring and the helical springs before mentioned, the crank arm is actuated
by springs so as to apply the rollers to the surface of the drum, whereupon, by the
consequent rotation of the roller, a chain, attached to part of its circumference and
to the helical band on the drum, is wound up on the roller so as to tighten the
band upon the drum and thus cause the rotation of the latter to exert a pull upon
the band, whereby the brakes will be applied.
It will be seen from this arrangement, that the greater the pull upon the chain,
the closer will be the contact between the roller and the drum and consequently
the more intense will be the straiu upon the band resulting in increased breaking
power. The before mentioned crank arms are connected by rods to similar crank
arms with contact rollers applied to the other axle of the vehicle so that when the
first mentioned crank arms are put in action, the second set of crank arms will be
simultaneously actuated. The crank arms are also connected by other rods by
means of which the second set are put out of action at the same time as the first
set.
The buffer rods are also connected by levers to the system of links actuating
the crank arms and contact rollers, so that when the buffers are pressed inwards to'
a certain extent, the contact rollers are, in like manner, applied to the drums, thus
effecting the application of the brakes. The said system of links is also connected
to a band lever projecting at the side of the carriage by means of which-the brakes

page_text: .
can be applied or taken off by hand. The same arrangement is also applicable in
cases where the draw bar and buffers are connected by one and the same blade
spring instead of by separate helical springs.
For this purpose, the connections of the draw bar and buffer rods respectively to
the centre and ends of. the spring are so arranged with slots as to permit of a
certain amount of motion without actuating the spring. The connecting sockets
are, however, made to bear against fixed stops so that an initial strain is always
maintained by them upon the spring. The drum on the axle is provided with an
outer sheathing of soft cast iron fixed on in halves in a removable manner, so that,
when they become worn by the friction of the brake band, they can be taken off
and replaced by new ones. The contact rollers are formed with side flanges which
fit with bevilled edges in corresponding bevil grooves formed on the drum so as to
obtain increased frictional hold:
According to another modification in which the brakes may also be applied
with adjustable power by hand, there are four drums with helical bands arranged
respectively against each of the four wheels of the vehicle and corresponding rollers
carried by levers actuated by helical springs are situated in a loop of the band
passing round the drum, the ends of the said band being connected to chains
extending to the centre of the vehicle; where they are attached to a shaft or pin
suspended by arms from a bracket on the framing. The helical springs are so
arranged that when there is no tension on the draw bar or pressure on the buffers,
the springs draw the rollers in the loops of the bands so as to tighten the loop and
thus apply the bands to the drums with sufficient breaking power. When tension
is applied to the draw bar or pressure is applied to the buffers, these effect, by
ineans of the same system of diagonal links as described in the previous arrange-
ment, the movement of the levers carrying the rollers in opposition to the action
of the springs so as to loosen the roller in the loop of the band and thus take off
the brakes. The levers carrying the rollers are extended up into the carriage
where they are formed as hand levers so as to operate the rollers by hand, or the
said levers may be actuated by hydraulic, steam or other power.
The connecting links are slotted so as to admit of the brakes being applied by
hand independently of the mechanism for applying them through the draw bars
and buffers.
According to another modification, the ends of the drum bands are each con-
nected to one of two rollers on opposite sides of the wheel, the rollers having
flanges that are brought in contact with the rim of the wheel, or in contact with
the periphery of the drum itself, so that, by their rotation, they tighten the drum
bands and so apply the breaking power. The rollers are carried by suspended
links that are connected by rods to the arms of brake shafts which are actuated by
helical springs so as to apply the rollers and, consequently, also, the brake power.
The draw bar has tappets fixed upon it which, during the first motion of the draw
bar, come in contact with levers connected with those carrying the friction rollers
and so move them out of contact with the wheel or drum, whereupon the elasticity
of the band on the drum will draw the chain off the rollers and the brakes will be
taken off. The draw bar has two helical springs of different power and length,
arranged end to end, the weaker spring being made to bear against the framing,
while the strong spring bears against a collar on the bar, so that, when at rest, the
springs draw the bar inwards so as to allow the brakes to be applied, but when
the bar is first drawn outwards, the weaker spring is first alone compressed, during
which time, the draw bar puts the brakes out of action as described, and, on the
continued outward movement of the bar, both the weak and the strong spring will
be compressed so as to afford the requisite resistance to the increasing traction.
The buffer rods are also provided with combined weak and strong springs
operating in the same manner as above described on the compression of the buffers,
which, as in the preceding cases, are also connected to the brake gear by a system
of levers, so that, when the buffers are first pushed inwards, during which time
only the weak springs are compressed, the brakes are taken off.

page_text: The before mentioned springs that apply the brakes, as also the coils of the
bands on the brake drums, are capable of adjustment so as to insure that the effort
of traction to move the vehicle when empty, shall be amply sufficient to take off
the brakes.
The contact or friction' rollers are so proportioned that the portions on which the
chains connected to the brake bands are wound, are of as small a diameter as
possible, while the parts which come in frictional contact with the wheels, are made
as large as possible.
By preference they are arranged as follows. Two rollers of disc form are
arranged loose upon the ends of one and the same axis, the middle of which is
carried by a boss of the supporting lever. The disc rollers have bosses of small
diameter to which the chains attached to the ends of the helical brake band are
respectively wound in opposite directions, so that when the road wheels and with
them the brake drums revolve in one direction, the one disc roller will be caused
to revolve so as to wind up the chain and apply the brake band, while the other.
disc roller will be prevented from revolving by the pull of its chain. On reversing
the motion of the carriage, the reverse action of the rollers will take place. The
lever carrying the rollers may be carried by a shaft having an arm with a roller in
contact with an incline upon the draw bar, so that the notion of the latter will
cause the shaft to be turned so as to move the disc rollers away from the brake
drum.
In applying the above described brake apparatus to vehicles running on common
roads, the brake drums may be fixed to the naves either of the hind or the front
wheels. In this case the one end of the belical brake band is attached to a fixed
pin or bracket on the axle tree or carriage frame, while the other end is connected
by a chain passing over a guide pulley to a balance bean carried by a central rod,
which is connected by levers and chains or rods to the brake treadle on the driver's
seat. The elasticity of the brake bands is sufficient to take off the brake pressure
when the treadle is not depressed. For applying the brakes through the action of
the horses, the free ends of the helical brake bands are connected to levers that are
also connected to a rod or chain passing through or alongside the shafts or pole of
the carriage, at the front end of which the chain is led over a guide pulley and
connected to the collar or other part of the horses harness, so that the backward
pull of the horse in stopping, or when falling will at once apply the brakes.
The brake drums may be fixed on the naves of existing wheels by providing
then with a flange with bolts passing between the spokes of the wheel to the outer
side where they pass through an annular plate and are secured by screw nuts.
For applying the above described systein of brakes with helical brake band to
winches and similar apparatus for raising and lowering, the chain barrel has
formed on it a brake drum of wood or metal, the helical brake band of which has
its one end attached to the framing while the other end is connected to a weighted
lever, arranged to apply the band with sufficient force to cause it to bite on the
drum when this is rotated in the same direction in which the band is coiled, such
direction being that in which the barrel turns when the weight is descending.
When the barrel rotates in the contrary direction for raising an object, the weight
on the lever is not sufficient to cause the brake band to bite. The band may be
made with such a number of coils that a very small weight on the lever will apply
the brake when the barrel revolves in the descending direction, in which case the
ordinary ratchet and pawl gear may be dispensed with.
Dated this 14th day of November 1885
ABEL & IMRAY,
Agents for the Applicant.

page_text: I, PAUL ARTHUR GAMBARO, of N° 159 Rue Lafayette, Paris in the Republic of
France Engineer, 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 upon brake apparatus such as was
described in my previous Patent of 23rd February 1884 N° 3834.
I will proceed to describe my present improvements referring to the accom-
panying drawings. In. the arrangement shewn on sheet I the break-action is
effected by means of a drum fixed upon the wheel axle, and not upon the rims
of the wheels. The traction bar operating the same and being discontinuous in
form and combined with traction and compression springs arranged with an initial
tension or pressure. In addition the mass of the parts requisite for actuating the
brakes is greatly reduced.
Fig. 1 shews a longitudinal section, Fig. 2 a cross section and Fig. 3 a plan of one
arrangement. The boxes containing the helical springs contain washers e held by a
shoulder on the box and loose on the traction and buffer bars. It will be seen that
if the traction bar T is actuated the key i will impart motion to the ring g which
will not actuate the washer until after it has passed through a distance of from
to of an inch indicated by a b. This movement is resisted by the opposing
helical springs J by the intermediary of the rods E and the compensator K. The
resistance of these springs J is only about 25 pounds. As however the distance ab
traversed is very small, there will be no appreciable shock at the moment when the
traction bar actuates the spiral spring L by means of the washer e. From this
moment the traction acts in the usual way. During the travel a b the traction
bar actuates rods D by means of a triangle E K E¹. The rods D support the friction
rollers G G¹ and by this motion remove these rollers from the drum E. The chains
of the brake bands H are then slacked and the brakes are taken off. On the other
hand when the traction bar ceases to be actuated it returns to its original position
by means of the spring L and the helical springa J. The rollers G G₁ are applied
with friction upon the drum F and if the direction of rotation is that indicated by
the arrows ffi the chain of the free end of the brake band will be coiled round
the roller G in the direction m n while the fixed end will be strained in the
direction p q
Figs. 4 and 5 shew in section and end view the detail of one diso of the roller G.
In one or other of the holes are fixed hooks or eyes to which are attached the
chains connected to the end of the brake band (see Figs. 6 and 7). It will be seen
that the tension of p q will tend to apply the rollers G G¹ to the drum all the more
energetically the greater the tension is and that consequently the adhesion will be
all the greater between the two cylinders, consequently the tension of the free
end m n will gradually increase until it attains the necessary force for tightening
the brake bands upon the drum. The movement of the rods D is transmitted to
the rods D¹ of the other axle by the intermediary of the bars PQ acting in tension;
and, vice versa, the movement of the rods D¹ would be transmitted to the rods D.
A slot R is adapted at one end of each of these bars P; Q so as to facilitate the
regulation of their length and also in order to avoid that the two bars P and Q

page_text: shall not act simultaneously when working the rods D D¹, the one bar operating
by traction while the other operates by compression. It will be seen that even if
this brake is arranged at the last carriage of a train the brakes of the last axle can
be actuated by the traction bar.
I will assume that the apparatus is to act by compression of the buffers. The
drawing shews that, as in the previous case, an effort say of 25 lbs. will be sufficient
to cause the rod of the buffer A to traverse the space cd in acting against the
helical springs J by the intermediary of the levers U U which actuates the
triangle E K E¹. It will also be seen that at the connections of this lever U
there are slots which prevent the actuating of the brake by means of the traction
bar being interfered with by the buffer rod and vice versa. This is also the case
with the lever B by means of which the brakes are worked by hand. This lever
can slide at the point O in the piece W, and there is therefore perfect independence
between the three modes of actuating the brake, that is to say, by traction, by the
buffers and by the hand-lever. This drawing also shews a modification in which
an ordinary blade buffer and draw-bar spring may be employed for actuating the
brakes, the springs having the necessary initial strain put upon them. The rod of
the buffer A can move through a distance of about half an inch in the interior of
the socket X by means of a key r which can be displaced in the socket. On the
other hand the latter bears against a support Y fixed to the under framing in such
manner that the blade spring Z can be placed in position with an initial strain, its
middle bearing against the frame beam by the intermediary of. blocks t.
drawing also shews how on the application of traction the traction bar T¹ can dis-
place itself relatively to the spring Z to the extent of the play a¹ b' of the key a in
the traction bar. The brake acts in the same manner as in the preceding case after
the point O¹ has been displaced to the necessary extent for taking off the brakes.
Figs. 8 and 9 shew separately the friction drum F in longitudinal section and
end view partly in section. These Figs. shew how the half cylinders ẞ can be
connected together with the drum. These half cylinders ẞ are of soft cast iron;
they are intended to take the wear and tear consequent on the friction of the brake
band H. Fig. 10 shews a modification of the drum of the friction rollers. These
latter can be made to fit into grooves of wedge form whereby the frictional contact
between the rollers and the drum is increased.
The
The arrangement shewn on sheet II also affords the advantages of the previous
arrangements; in addition it allows of the power of the hand brake being adjusted.
Sheet II shews in longitudinal section at Fig. 1 in plan Fig. 2 and in half transverse
section Fig. 3 an arrangement of the brake which is capable of adjustment by hand,
such adjustment being direct and therefore rapidly effected. This brake is auto-
matic with limited pressure determined beforehand. Four springs are applied to
a roller P which applies tension to a brake band H on a drum T fixed on each
wheel, the brakes being applied when at rest. The axis U constitutes a fixed point.
The drawing shews that for the two axles and with the rotation in the direction of
the arrow the traction of the two chains q q and q¹ q¹ will be in equilibrio on U
which oscillates round the axis V. On the other hand the ends mom and m² m²
will become slack. The greater the tension of the springs r, the greater will be the
energy with which the brake band is applied; the brakes are applied when at
rest. If the engine draws on the draw hook in the direction of the movement, the
rod Q actuates the compensating triangle D' D¹ and approaches the pulley P¹ of the
brake band by the intermediary of G¹ G¹ and L¹ L¹. The chain k is then no
longer strained and the brakes will be taken off. The movement of the lever L³ L'
is transmitted by the rod a a to the lever L L and thus effects simultaneously the
taking off of the brakes at the other axle. These levers might be replaced by apy
other power such as compressed air which affords tension variable at will, and
would thus permit of a variable brake pressure being applied. The working of the
brakes by hand may be effected by means of the lever L L in inclining this to the
right hand the springs are actuated and the tension of the chain h h¹ upon
the brake band is diminished so as to diminish the brake. power. Inversely the

page_text: brake power may be increased by moving the lever to the other hand. The
bars a abb transmit the action of the lever L to the other axle; the lever L may
be made to slide in the parts for actuating the brakes by traction so that the two
act independently. On the occurrence of compression of the buffers, the action of
the latter is transmitted to the traction bar by means of the levers E for taking off
the brakes.
Sheet III shows the application of the system of brakes described in my previous
Patent to rolling stock analogous to that which is employed on American railways.
The drums O are fixed to the wheels; the helical steel brake bands Hare coiled
upon these drums with a certain amount of play. Each of the two ends of a brake
band is provided with a chain capable of being coiled upon the rollers G G¹. These
are rotated by friction either upon the tyres of the wheels or upon the drums OO
themselves. Referring to the arrangement shewn on Figs. 1, 2, 3 and 4 of
sheet III I will assume that the arrows findicate the direction of the movement;
so long as the rollers G G are not applied with friction, the wheels and their
drums will turn freely within the brake bands. If, on the contrary, the rollers
are brought into gear by the action of the spring N, the chains a a will be coiled
upon the corresponding rollers G¹. The brake bands will then be tightened upon
the drums whereupon the rotation of these will have the effect of tightening the
brake bands still further upon them because the other end of the brake band to
which the chain b is attached will draw against a fixed point obtained by the
contact of the other rollers G upon the rims. By this means the brakes will be
. applied with all the greater power, the greater is the speed of rotation of the
wheels. If the application of the rollers G. G¹ upon the rims is discontinued the
ends of the chains a are drawn back by the elasticity of the brake bands and as
this movement is no longer counteracted as soon as the friction of the rollers ceases
the brakes will be taken off. If the motion of the train is reversed the chains 6 of
the rollers G will become the free ends of the brake bands which effect tension
while the chains a of the rollers G¹ will become the fixed points. In this arrange-
ment the brakes are actuated in the following manner.
I will assume that the
direction of motion is that indicated by the arrows f.
The traction bar T has two springs R and r (Fig. 4) of very different strength.
I will assume that the spring is depressed by the effort necessary for removing
the rollers from the wheels and that this effort is less than that necessary for
moving the empty carriage into a siding. On the other hand, this spring is so
arranged that the traverse of the traction hook corresponding to its deflection shall
be sufficient for removing the rollers from the wheels by the intermediary of the
suspension rods d d' and the rods / and 8. The studs E fixed upon the traction bar
actuate the rods D and the movement of the latter is transmitted to the rods D¹ by
the intermediary of the suspended rods s and l. It will be seen that all these
movements are conveyed to the axis of the carriage by means of the bars W and
that if Figs. 1 and 2 represent one of the two bogies of a vehicle, the movements
of the rods 68 will be transmitted to the similar parts of the other bogie by these
bars supported at their middle. It will be sufficient to connect the other ends of
these bars to a suitable point above or below the axis of rotation of the rods D D¹
so that it is not indispensable to employ a continuous traction bar T. The action
of the brakes, when the buffers are compressed by the engine, will be as follows:
The buffers C have resisting springs q and Q of unequal strength as in the case of
the springs R and r of the traction bar T. The buffer rods act upon the levers P
having their fulcra at X. The other end of these levers P actuates the bars L
Fig. 1 and consequently the rods ls and D D¹. The rods are thus removed from
the wheels and the brakes are taken off. The drawing shews how, as soon as the
rollers are no more actuated for removing them, the springs N will act for bringing
the rollers in contact again. Thus every time that the locomotive ceases to actuate
the vehicle either by traction or by pressure, the brakes will be applied. The
brakes are thus automatic and will come into action on a detached part of a train
in the case of rupture. It will be seen that the pressure of the rollers upon the

page_text: wheels can be regulated by means of the springs N. On the other hand, as by
increasing the number of coils of the brake band and the diameters of the drums,
one can effect the application of the brakes with as small a strain as may be
desired upon the free ends of the brake band, it results that the brakes may always.
be so arranged that they are brought into action with an effort less than that
which is necessary for moving the empty vehicle into the shed.
It is advisable that the chains of the brake bands in being coiled upon the
rollers should be coiled round a part, the diameter of which is as small as possible
while the diameter of the part where the friction is applied should be as large as
possible. It is also advisable that this latter diameter should approximate as near
as possible to the diameter of the wheel and as this cannot be practically carried
out, it is preferable to arrange the rollers to come in contact with the drums of the
brake bands, making them as nearly as possible of the same diameter; Figs. 5 and 6
shew this arrangement. For this purpose two rollers g g¹ are arranged loose upon
one and the same axis and are separated by a suspension rod D. If the direction of
rotation is that of the arrows f the chain a of the free end of the brake band will
be coiled upon the roller g¹ in frictional contact with the drum while the other
roller g in bearing upon the drum will afford a fixed point for the tension of the
chain b. The brake band will be tightened with all the greater force, the greater
is the pressure of the rollers upon the drum, consequently the adhesion of the
roller & will gradually increase and the brake power will be increased in a
corresponding manner. This arrangement affords much greater power than the
preceding one.
The applying or the taking off of the brakes will be effected by the applying
or removal of the rollers, that is to say by the movement of the lever D. This
movement is readily effected by means of the shaft K, the cam M and the roller p..
Counterweights R and draw-back springs 7 permit of the weight of the rollers
being put in equilibrium and of affording automatic breaking. It is evident that
an arrangement might be adopted in which the preceding rollers g g₁ are applied
on the sides of the drum instead of at the top.
Figs. 1, 2 and 3 of sheet IV shew in elevation, plan and end view the application
of my improved brake to a road vehicle of any description. The example here
shewn represents an omnibus with three horses, this being one of the most
difficult cases. The drawing shews the application of the brake firstly to the
naves of the large hind wheels, the brakes being actuated by the driver; secondly
to the naves of the small wheels in front, the brakes being applied by the horses.
One of these arrangements alone would be sufficient for the vehicle. The fixed
ends of the brake bands H are at B. The react upon the axle D at the connection
of the suspending springs. The levers J and I constitute a compensator for the
tensions of the cords I R actuating the free ends of the brake bands. The action
of the driver is transmitted to the compensator II by the pedal N N the
chains M M the bars and levers LLKK JJ guided by rollers. The elasticity
of the brake bands is sufficient for taking off the brakes as soon as the free
ends are no longer acted upon. With regard to the arrangement for actuating
the brakes of the front wheels by the horses, it will be seen that the free ends
of the brake bands are actuated by levers o. These latter are actuated by the
rods and chains P P of which the extremities passing over guide pullies Q are
attached to the halters or traces of the horses. These connections being made
shorter than the chains of the harness it results that for stopping, the horses
actuate the brakes so as to apply them before they exert their force in stopping
the vehicle by means of the chains or other ordinary devices. It will also be
seen that if a horse falls he will thereby cause the brakes to be applied and stop
the vehicle.
Figs. 4 and 5 shew firstly a mode of adapting on the naves of the wheels the
friction drums of the brake bands and secondly a detail of the attachments of
the ends of the brake bands. These latter may be made of tapering section from
the fixed point towards the free end; lastly the fixed point should be behind in

page_text: the sense of the rotation, as this fixed point is considerably strained at the moment
of applying the brakes, the action upon it might be decreased by interposing a
spring between the fixed point and the corresponding end of the brake band.
This improved system of brakes may also be applied to apparatus such as
winches, as shewn at Figs. 6 and 7. The brake band is in this case applied to
cheeks formed of cast iron or preferably of wood fixed on the barrel of the winch,
the fixed end, viz. that behind the direction of rotation, is connected at A, for
example the chain A B serving to take the strain when the load is being lowered.
The free end E F is connected to a lever G H of the second order. A counter-
weight K is made of sufficient weight to apply the brake during the lowering of
the load P so as to stop this from descending if from any cause the crank handles
be let go of without putting in gear the retaining pawl. On the other hand, during
the raising of the load the action of the counterweight K upon the brake band is
insignificant, as the direction of rotation of the drum is the reverse of that of the
coiling of the brake band. Thus, it will be seen that the brake will be out of
action while the load is being raised and will be brought automatically into action
for preventing the descent of the load so that for permitting this descent it is
necessary to lift the lever G H. With a suitable coefficient of friction and number
of coils of the brake band, the stop ratchet might be dispensed with. With
brakes of ordinary winches or cranes the brakes are made to act upon intermediate
shafts and consequently the breaking of these shafts or of the teeth of the gearing
may render the brake useless. This is avoided with the arrangement of brakes
above described.
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 in respect of brake apparatus of the kind herein referred to is :-
1. The arrangement of friction rollers gearing with the drum of the brake band
instead of on the wheels, substantially as described with reference to sheet I.
2. Actuating the brakes by means of the traction bar combined with buffer and
draw bar springs, having an initial tension substantially as described with reference
to sheet I.
3. The herein described construction whereby the mass of the parts actuating
the brakes is reduced, substantially as described with reference to sheet I.
4. The arrangement whereby the traction bar is rendered discontinuous sub-
stantially as herein described with reference to sheet I.
5. The arrangement herein described with reference to sheet II whereby the
brake power can be modified by hand.
6. The arrangement herein described with reference to sheet II whereby the
degree with which the brakes are applied automatically is limited.
7. The arrangement herein described with reference to sheet III for applying
the brake apparatus to rolling stock of the American type.
8. The arrangements herein described with reference to Figs. 1, 2, 3, 4 and 5 of
sheet IV for applying the brake apparatus to road vehicles.
9. The arrangements herein described with reference to Figs. 6 and 7 of sheet IV
for applying the brake apparatus to machinery for raising and lowering weights.
Dated this 11th day of August 1886.