AN IMPROVED COMPOUND BRAKE APPARATUS
Year: 1881

page_text: LETTERS PATENT to William John Adams, of Queen Victoria Street, in the
City of London, Engineer, for an Invention of "AN IMPROVED COMPOUND
BRAKE APPARATUS."
*
PROVISIONAL SPECIFICATION left by the said William John Adams at the
Office of the Commissioners of Patents on the 21st February 1881.
WILLIAM JOHN ADAMS, of Queen Victoria Street, in the City of London, Engineer.
"AN IMPROVED COMPOUND BRAKE APPARATUS."
This Invention relates to a means of operating automatically the brake apparatus
fitted to a train of carriages, and the brake apparatus applied to the engine of such
train when the engine is fitted with a steam brake and the carriages are fitted
with pneumatic or hydraulic brakes.
Supposing, for example, the brake apparatus with which the carriages are fitted
to work on the principle of destroying the vacuum in the pipes, as in the "Smith"
and "Hardy" brake apparatus, I fit to the engine, which is provided with a steam
brake, a steam reducing valve, preferably of the construction patented by Bowman
Malcolm, dated November 8th, 1879, No. 4553, and the plunger of this valve I
operate by the pressure of a rod attached to the piston of what is known as a
Hardy" cylinder, which cylinder I connect below its piston with the system of
vacuum brake pipes. Thus when vacuum is formed on both sides of the piston
the piston will fall, and its rod will be clear of the plunger of the reducing valve,
but so soon as air is admitted below the piston, either by the severance of the train
pipe couplings, or by opening an admission valve, the piston rod will rise, lift the
plunger of the steam valve, and thereby cause steam from the boiler of the engine
to set the steam brake in action. By this means the two brakes will be brought
within the control of the guard as well as the engine driver, and will in case of an
accident occuring come simultaneously and automatically into action.
It will be understood that other well known means acting in a similar manner
to the "Hardy" cylinder may be used for setting the steam valve in action, the
details of such means depending on the system of brake apparatus used upon the
carriages. Thus in adapting the "Hardy" cylinder for use with compressed air,
it will be necessary to reverse the action of the valve in the piston, or to connect
the train pipe with the cylinder above the piston instead of below it, as above
mentioned.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William John Adams in the Great Seal Patent Office on the 20th
August 1881.
WILLIAM JOHN ADAMS, of Queen Victoria Street, in the City of London, Engineer.
"AN IMPROVED COMPOUND BRAKE APPARATUS."
This Invention relates to a means of operating automatically the brake apparatus
fitted to a train of carriages, and the brake apparatus applied to the engine of such
train when the engine is fitted with a steam brake and the carriages are fitted
with pneumatic brakes.
Supposing, for example, the brake apparatus with which the carriages are fitted
to work on the principle of destroying the vacuum in the pipes, I fit to the engine
which is provided with a steam brake a steam valve, and the stem of this valve I
operate by the pressure of a lever attached to the piston rod of a cylinder, which
cylinder I connect below its piston with the system of vacuum brake pipes. Thus
when vacuuin is formed on both sides of the piston the piston will fall and its
lever will be clear of the stem of the steam valve, but so soon as air is admitted
below the piston, either by the severance of the train pipe couplings or by opening
an admission valve, the piston rod will rise, lift the steam valve, and thereby cause
steam from the boiler of the engine to set the steam brake in action.
In the accompanying Drawings I have shewn two arrangements for carrying out
the object of my Invention. In Sheet I., Fig. 1 is a plan view of the apparatus
which connects the vacuum brakes of the carriages with the steam brake of the
engine; Fig. 2 is a vertical section of the same taken in the line 1, 2, of Fig. 1,
and Fig. 3 is a vertical section taken in the line 3, 4, of the same Figure.
This apparatus which is secured to the engine boiler consists of a casting
containing three cylindrical chambers A, B, and C. The chamber A opens to the
steam boiler at a, and is fitted with a steam valve a¹. It also communicates by a
passage a² with the chamber B, which is fitted with a cylindrical reducing slide
valve b. The chamber C consists of a vacuum cylinder and is fitted with a sliding
piston c through which a passage is made controlled by a loose disc valve at bottom
so constructed as to allow of air being drawn down from the upper side of the
piston for the purpose of maintaining a vacuum in the chamber C.
This chamber communicates below its piston with a pipe D leading to the
vacuum brake apparatus, and through this pipe the chamber is exhausted.
Similarly the cylinder B communicates through the pipe E with the steam brake
apparatus.
In communication with this cylinder is also an exhaust pipe F which takes the
steam returning by the pipe E from the engine brake cylinder when that brake
is thrown out of action, and discharges it into the atmosphere or conducts it to the
ejector to be there utilized to restore the vacuum.
G' is a lever underlying the chambers A, B, C, and pivotted to lugs forming part
of the casting.
Upon the upper edge of this lever when in its raised position rests the stem of
the steam valve a'. This lever passes through a vertical slot made in the lower end
of the cylindrical reducing valve b, and it extends to and enters a slot in the piston
rod c¹ of the piston c.
A tendency is given to the valve a¹ by means of a coiled pressure spring a³ to
recover its seat when it has been forced therefrom.
I will now explain the action of this apparatus, premising that in the Drawing
the working parts are shewn in the position which they will take when the brakes
are out of action. At this time the piston c is at its lowest position, having fallen
by its own gravity being in equilibrio.

page_text: This depression of the piston forces the lever G to its lowest position and causes
it to draw down the cylindrical reducing valve b so as to close the steam opening a³
between the chambers A and B.
When the lever is in this depressed position it will be clear of the stem of the
5 steam valve a¹, and that valve will therefore rest upon its seat, it being held
there by the downward pressure of the steam admitted from the boiler by the
opening a.
So soon as the vacuum below the piston c is destroyed by the automatic or other
action which puts on the vacuum brakes, the piston c will rise (its little disc valve
being forced up to its seat), lift the lever G to the dotted position of Fig. 2, and
thereby cause that lever to raise the cylindrical valve b and the valve a¹ to the
dotted position of Fig. 2.
The steam from the boiler will now pass the valve a', enter by the passage a²
the chamber B, and passing round the cylindrical valve b will escape by the pipe E
to the steam brake apparatus on the engine, and thus apply the engine brakes.
The steam at the same time passes through a central opening b¹ in the valve b to
the top of the valve, and as soon as the pressure in the steam brake cylinder
exceeds a given pressure, the piston 6' will be forced down and close the
opening a², so that a pressure corresponding to that in the pneumatic apparatus
will be given in the steam cylinder.
So soon however as the vacuum is restored to the vacuum brake pipe, the
piston c will fall, carry down the lever G to its drawn position, and allow the steam
valve a¹ to close, while at the same time it opens a passage from the steam brakes
by the pipe E and chamber B to the exhaust pipe F.
It will be understood that the areas of the vacuum piston and the reducing valve
piston must be proportioned to give the desired pressure in the steam brake
cylinder.
From the foregoing description it will now be understood that the two kinds of
brakes will be brought within the control of the guard as well as the engine driver,
and will in case of an accident occurring come simultaneously and automatically
into action.
.
In Sheet II., Figures 4 and 5 shew in side elevation and in vertical section a
more simple arrangement of the apparatus, by which I bring within the control
of the guard the two kinds of brakes.
A is a hollow casting made fast to the boiler of the engine. The uppermost
division a of this casting is in steam communication with the boiler, and it is closed
against a division or chamber b by a valve B, which is held up against its seat by its
stem being borne upwards by the stem of a pneumatic lever C. One side of
this pneumatic lever is open to a vacuum chamber c, and the opposite side to
the atmosphere.
The stem of this pneumatic lever works through a solid part of the casting A
as in a guide, and it is surrounded by a coiled spring which puts a slight
downward pressure on the pneumatic lever.
The chamber c is in cominunication through the pipe D with the vacuum brakes
of the train, and the chamber b is in communication through the pipe E with the
steam brakes of the engine.
So soon as the vacuum is destroyed in the chamber C by the putting on of the
carriage brakes, the stem of the pneumatic lever will drop and allow the valve B
to open under pressure of the steam which will pass into the chamber 6, and by the
pipes E to the steam brakes.
To provide for the escape of the steam from the brakes at the time the vacuum
is being restored,. I provide a two-way cock which will simultaneously close
the air admisssion pipe, and open a passage for the escape of the exhaust
steam. This cock will be under the control of the engine driver.
It will be understood that the other well known means for setting the piston
or pneumatic lever in action so as to control the steam valve may be used, the
details of such means depending on the system of brake apparatus used upon

page_text: the carriages; thus, for example, in adapting what is known as the "Hardy"
cylinder for use with compressed air, it will be necessary to reverse the action of
the valve in the piston, or to connect the train pipe with the cylinder above the
piston instead of below it, as above mentioned.
Having now set forth the nature of my Invention of "An Improved Compound
Brake Apparatus," and explained the manner of carrying the same into effect,
I wish it to be understood that under the above in part recited Letters Patent
I claim,―
Combining pneumatic brakes with steam brakes by means of apparatus consisting
essentially of a steam valve controlled by a piston or pneumatic lever, which
receives its impulse from the pneumatic brake apparatus, in the manner and for
the purpose above set forth.
In witness whereof, I, the said William John Adams, have hereunto set my
hand and seal, the Sixteenth day of August, in the year of our Lord One
thousand eight hundred and eighty one.
W. J. ADAMS. (..)