Improvements in connection with Signalling on Trains.
Year: 1892

page_text: Date of Application, 31st Dec., 1892
Complete Specification Left, 23rd Sept., 1893-Accepted, 25th Nov., 1893
PROVISIONAL SPECIFICATION.
Improvements in connection with Signalling on Trains.
I, ALEXANDER SHIELS, of 190 Bath Street, Glasgow, M.B., C.M., B.Sc., do
do hereby declare the nature of this invention to be as follows:-
―
This invention relates to signalling on trains, and it has for its object to utilize,
in an improved manner, the Westinghouse or other pressure brake system for this
purpose.
In my prior application, dated the 30th day of December 1892, I have described
an apparatus for signalling on trains where the vacuum brake is used, and my
present invention is for the application of the same principle to pressure brakes.
In this invention, as in my prior invention, I use a passenger's air or release
valve, a controlling valve and, if necessary, a cut-out valve. The air and cut-out
valves may be of practically the same construction as those described in my prior
application aforesaid, but the controlling valve is or may be of different construction.
The valves of course, since we are dealing with pressure instead of vacuum, act
in a reverse manner to those described in my prior invention.
valve
In carrying out my invention, I actuate the passenger's air, or "release" valve,
as I, in this case, term it, by means of a chain and pulley arrangement as described
in my prior application. A pipe leads from the underside of the "release
down to the controlling valve casing, which is or may be made in two parts. In
the one part is fitted the controlling valve, which may be of any suitable construc-
tion, but is preferably a ground metal valve, and which has a long guide and
actuating spindle passing through or attached to it. At the back of the valve or
other place, is a spiral or other spring, which normally tends to press the valve
outwards from its seat. A screw cover may be fitted at the back of the valve, for
the purpose of giving access to it at any time. The guide spindle is connected, at
its outer end, to a diaphragm or piston, or their equivalent, which is secured or
fitted in the other part of the casing. The casing is air tight and a pipe or passage,
which has an automatically closing valve in it, connects the air spaces at both
sides of the diaphragm or piston. Storage reservoirs or pipes may be fitted in
connection with these air spaces. Leading from the back or underside of the
controlling valve, is a pipe which passes to the cut-out valve box and train pipe.
A bye-path passage is left or made at, or near, the controlling valve.
The action of the apparatus is as follows:-Whenever the passenger pulls the
chain in his compartment, the release valve is opened and the compressed air in the
controlling valve casing and train pipe is allowed to escape to a limited extent and
so partially apply the brakes, the pressure in the controlling valve casing at one
side of the diaphragm or piston is also destroyed, and, as a consequence, the locked.
up pressure at the other side of the diaphragm or piston, forces said piston or
diaphragm inwards, against the pressure of the spring, and gradually closes the
controlling valve. The small valve in the passage way, communicating with the
compartiments or spaces at both sides of the piston or diaphragm, is, at this time,
closed down on its seat by the difference of pressure at both sides of the diaphragm
or piston, so that the locked up pressure cannot escape. When the controlling
valve is closed, the driver can again pump up his pressure to its normal limits in
the train pipes, and so release the partially applied brakes, and keep the train under
his full control, so that he can, with ease, run to a place of safety. The diaphragm
or piston is, by preference, always made much larger in area than the valve, so that,
it keeps said valve closed against its seat, when the driver is pumping up his pressure.
When the passenger's release valve is again closed by a train official, and the
pressure is being again pumped up in the train pipes, during the time that the
controlling valve is also closed, a leakage of pressure takes place from the train

page_text: pipes, past the valve or through the bye-path passage, into the inner compartment
of the diaphragm or piston casing, and this pressure gradually increases until, when
it reaches the normal, it balances the pressure of the locked-up air in the other
compartment of the casing, and thereby allows the spring to act and force back the
piston or diaphragm to its original position. The backward movement of the
diaphragmn or piston moves back the controlling valve to the open position, so that
the pressure is now equal in all parts of the apparatus, and it is in its normal state
ready for another signal.
"
Should the pressure increase, in the near compartment of the diaphragm or piston
casing, above the normal, it opens the valve in the communicating passage and
allows pressure to pass into the outer compartment, and thereby equalize the
pressure on both sides of the piston or diaphragm. The self-acting stop valve in
the communicating passage only closes against its seat, whenever the pressure in
the inner compartment is destroyed or partially destroyed.
The cut-out valve consists of a self-acting valve, which closes against its seat,
and thereby cuts off communication between the controlling valve casing and the
train pipes, whenever the pressure in the train pipes is reduced by the ordinary
application of the brakes. The cut-out valve saves wear and tear of the controlling
valve mechanism.
Under a modification, instead of having the diaphragm or piston enclosed in an
air-tight casing, the diaphragm or piston may be open at one side to the atmosphere,
and closed at the other side; in this case, when the pressure at the closed or inner
side of the diaphragm or piston is destroyed or reduced by the opening of the
passenger's release valve, the pressure at both sides of the diaphragm or piston
are equalized, and the spring, which, in this case, is made so as to normally tend to
close the controlling valve, comes into action and closes said valve, so that the
driver can again pump up his pressure as before.
The passenger's release valve may be actuated by a lever, or by a pin on the
chain wheel, and it is actuated, so as to open against the action of a spring, which
normally tends to close the valve against its seat.
Instead of using an ordinary packed piston or a diaphragm, a loose piston may be
used, with a cup leather at one side only. In this case, the communicating passage
and its valve may be done away with, as the action of the cup leather is sufficient.
The spring on the controlling valve is so arranged as to limit the amount of
reduction of pressure in the train pipes, whenever the passenger's release valve is
opened.
In some cases, if so desired, weights may be used instead of springs, and the
valves may be either ball, slide, flap, piston valves, or they may be of any other
well-known construction, with suitable actuating mechanism.
The self-closing cut-out valve is, preferably, a ball or cone valve.
The general construction of apparatus is similar to my prior application aforesaid.
Dated this 30th day of December 1899
H. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.
COMPLETE SPECIFICATION.
Improvements in connection with Signalling on Trains.
1, ALEXANDER SHIELS of 190 Bath Street, Glasgow, M.B., C.M., B.Sc., 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 signalling on trains, and it has for its object to utilize,
in an improved manner, the Westinghouse or other pressure break system for this
purpose.
In my prior application dated the 30th day of December 1892 No. 24067, I
have described an apparatus for signalling on trains where the vacuum brake is

page_text: used, and my present invention is for the application of the same principle to
pressure brakes.
In this invention, as in my prior invention, I use a passengers' air or release
valve, a controlling valve and, if necessary, a cut out valve. The air and cut out
valves may be of practically the same construction as those described in my
prior application aforesaid, but the controlling valve is or may be of different
construction.
The valves, of course, since we are dealing with pressure instead of vacuum,
act in a reverse manner to those described in my prior invention.
"
In carrying out my invention, I may actuate the passengers' air or “release
valve, as I, in this case term it, by means of a chain and pulley arrangement as
described in my prior application. A pipe leads from the underside of the
"release" valve down to the controlling valve casing, which is or may be made in
two parts. In the one part is fitted the controlling valve, which may be of any
suitable construction, but is, preferably, a ground metal valve, and which has a
long guide and actuating spindle passing through or attached to it. At the back
of the valve, or other place, is a spiral or other spring which normally tends to
press the valve outwards from its seat. A screw cover may be fitted at the back
of the valve, for the purpose of giving access to it at any time. The guide spindle
is connected, at its outer end, to a diaphragm or piston or their equivalents,
which is secured or fitted in the other part of the casing. The casing is air tight
and a pipe or passage, which has an automatically closing valve in it, connects the
air spaces at both sides of the diaphragm or piston. Storage reservoirs or
pipes may be fitted in connection with these air spaces. Leading from the back
or underside of the controlling valve, is a pipe which passes to the cut-out valve
box and train pipe.
A bye path passage is left or made at, or near, the controlling valve.
The cut out valve consists of a self-acting valve which closes against its seat,
and thereby cuts off communication between the controlling valve casing and the
train pipes, whenever the pressure in the train pipes is reduced by the ordinary
application of the brakes." The cut out valve saves wear and tear of the con-
trolling valve mechanism.
Under a modification, instead of having the diaphragm or piston enclosed in
an air-tight casing, it may be open at one side to the atmosphere, and closed at
the other side; in this case, when the pressure at the closed or inner side of the
diaphragm or piston is destroyed or reduced by the opening of the passengers'
release valve, the pressures at both sides of the diaphragm or piston are equalized,
and the spring, which, in this case, is made so as to normally tend to close the
controlling valve, comes into action and closes said valve so that the driver can
again pump up his pressure as before.
The passengers' release valve may be actuated by a lever, or by a pin on the
chain wheel, and it is actuated, so as to open against the action of a spring, which
normally tends to close the valve against its seat.
Instead of using an ordinary packed piston or a diaphragm, a loose piston may
be used, with a cup leather at one side only. In this case, the communicating
passage and its valve may be done away with, as the action of the cup leather is
sufficient. The spring on the controlling valve is so arranged as to limit the
amount of reduction of pressure in the train pipes, whenever the passengers' release
valve is opened.
In some cases, if so desired, weights may be used instead of springs, and the
valves may be either ball, slide, flap, piston valves, or they may be of any other
well-known construction, with suitable actuating mechanism.
The self-closing cut-out valve is, preferably, a ball or cone valve.
The general construction of apparatus is similar to my prior application
aforesaid.
And in order that my said invention may be properly understood I have hereunto
appended two explanatory sheets of drawings, whereon,

page_text: .
Figs. 1, 2, 3, 4 and 5 are sectional views showing different constructions of the
device.
Fig. 1 is a detail view.
Referring to the drawings whereon the same reference letters wherever repeated
indicate the same or similar parts, it will be seen that the device is very similar in
its general features of construction to the device described in the Specification of
my aforesaid prior invention No. 24067 of 1892.
On the drawings the passengers' "air" or "release" valve is not shown as it is,
or may be, of the same construction as that set forth in my prior application
aforesaid. The arrangement of cords or chains for actuating the valve may also
be the same.
"
As will be seen the construction of controlling and "cut out' valves shown at
Figs. 1, 2 and 5 are similar to those shown at Figs. 6 and 7 of my prior application
aforesaid. In this case, referring to Fig. 1,-1 is the controlling valve box which
is divided into compartments a, b, c, d; 2 the branch leading to the passengers'
"release" valve; 3 the controlling valve; 4 the controlling valve spindle which is
hollow; 5 the spring; 6 and 7 are the main compartments of the controlling valve
box; 8 is the passage way leading to the train pipes; 9 is the flexible diaphragm ;
10 is the partition between the compartments a, c. 11 is a hole in the partition ;
12 is a web which divides the compartments a, b, and it also serves to carry a seat
for the valve 3; 13 is a hole in the web; 14 is a screw cap secured on the branch 15
of the valve box; 16 is an internal adjusting nut screwed into the branch 15-this
nut has a central guide hole 16ª in it for one end of the spindle 4; 17 are holes in
said nut for enabling it to be screwed up; 18 is the cover of the chamber or com-
partment d; 19 is an internal pap on the cover having a guide hole in it for the
other end of the spindle 4; 20, 21 are holes made in the hollow spindle, one at
each side of the diaphragm; 22 is a collar fitted on the spindle over the hole 21
(see also Fig. 1A), this collar has a hole in it communicating with the hole 21 and
it is covered by an elastic band 23 which serves the purpose of a valve as hereinafter
described;-24 is a supporting web, cast in the valve box, for the diaphragm ;
25 is the "cut-out" valve; 26 is the spindle of the valve; 27 is a screw plug with
central guide hole; 28 is the valve seat made on the web or partition 29; 30 is the
branch leading to the train pipes. As will be seen in this figure the valves 3
and 25 are rubber disc valves the same as those shown in Fig. 6 of my prior
application aforesaid.
Fig. 2 differs from Fig. 1 in that the valves 3 and 25 are ground metal valves,
the spindle is solid, and the cup leather piston valve 31 replaces the diaphragm 9
otherwise the construction is the same. The piston valve consists, as in my prior
Patent aforesaid, of a loose disc 31*, with cup leathers 32ª at one side only. 22* is
a packing ring.
"
Fig. 3 differs from Fig. 1 in that there is a bye-path passage leading from the
back of the diaphragm 9 to the passage way 8. The spindle 4 is in this case also
solid. The bye path passage consists of a pipe 32 which is coupled at each end to
hollow branches or projections 33, 34, cast on the cover 18 and "cut out valve
box respectively. 35 is a small ball valve inserted in a cup-shaped socket piece
fitted in the coupling 36. 13 is a small bye path passage in the seat of the
valve 3. This passage may be used alone in lieu of the hole 13 or in conjunction
therewith.
Fig. 4 differs from Fig. 2 in having a hollow spindle 4 and valve 23, a solid
piston 31 with packing rings on its periphery (instead of the cup leather piston)
and also a ball valve 25-instead of a ground metal disc valve. It will also be
noted that in this figure the hole 20 is at the opposite end of the hollow spindle 4
to the hole 21.
In Fig. 5 the chamber or compartment 7 is made much longer than at Fig. 1 and
the spring 5 is placed in it so as to bear against the back of the diaphragm.
37 is a bearing plate. 38 are air holes in the cover.
Under normal conditious the compartments a, b, c and d are, equally with the

page_text: In
passages 8 and 30, filled with compressed air which passes in through the
holes 13, 11, 20 and valves 21, or round the edge of the piston valve 31 in Fig. 2.
In Fig. 3 compressed air passes into the compartment d through the valve 35.
Fig. 5 the compartment d is not filled with compressed air, but is open to the
atmosphere.
The action of the apparatus, referring to Figs. 1 and 4 of the drawings, is as
follows:-
"
When it is desired to give a signal the passenger pulls the cord or chain in his
compartment, and, as a consequence, as explained in my said prior application, the
air or "release" valve is opened, and, in this case, as we are dealing with
pressure, compressed air in the controlling valve casing and train pipes is allowed
to escape to a limited extent and so partially apply the brakes, the pressure in the
pipe 2, and compartments a and b is also destroyed. As the compressed air leaks
through the hole 11 the pressure in the compartment c is also gradually destroyed.
As a consequence the locked up pressure in the compartment d at the back of the
diaphragın 9, (or in Fig. 4 at the back of the piston 31) which cannot escape owing
to the pressure closing the rubber band 23 down tight over the holes 21, forces
said diaphragm (or piston) inwards against the action of the spring 5, and
gradually closes the controlling valve 3 against its seat.
When the valve 3 is thus closed, the driver can again pump up his pressure to
its normal limits in the train pipes and so release the partially applied brakes and
keep the train under his full control, so that, he can, with ease, run to a place of
safety. The diaphragm (or piston) is, by preference, always made much larger in
area than the valve 3, so that, it keeps said valve closed against its seat when the
driver is pumping up his pressure.
When the passengers" "release" valve is again closed by a train official, which
may be done in the manner explained in my said prior application, and the pressure
is again pumped up in the train pipes, during the time that the controlling valve 3,
is also closed, a leakage of pressure takes place from the train pipes, through the
hole or bye path passage 13, and passage 11, into the compartment c and this
pressure gradually increases until, when it reaches the normal it balances the
pressure of the locked up air in the compartment d, and thereby allows the spring 5
to act and force back the diaphragm 9 (or piston 31) to its original position. The
backward movement of the diaphragm (or piston) moves back its spindle 4 and
with it the controlling valve 3 to the open position as shown on the drawings.
The pressure is now equal in all parts of the casing and the apparatus is ready for
another signal.
Should the pressure increase, in the compartment c above the normal, it passes
through the hole 20, opens the band valve 23 and allows pressure to pass into the
compartment d and thereby equalize the pressure on both sides of the diaphragm
(or piston). The self-acting band stop-valve on the hollow spindle 4 only covers
over and tightly closes the hole 21, whenever the pressure in the compartment c is
destroyed or partially destroyed, that is to say it only closes when the pressure in
the compartment d is greater than in c. The cut out valve 25 is a self-acting one
and closes against its seat 28, thereby cutting off communication between the
controlling valve casing and passage 30 leading to the train pipes, whenever the
pressure in the train pipes is reduced by the ordinary application of the brakes.
The cut out valve saves wear and tear of the controlling valve mechanism.
In the modification shown at Figs. 2 and 3 when the passengers' release valve is
opened the pressure in the compartments a, b, and c is destroyed so that, as before,
the diaphragm (or piston) owing to the difference of pressure in the compartments c
and d, is forced inwards so as to again gradually close the valve 3. In this
arrangement the cup leather piston valve (Fig. 2) and also the ball valve 35
(Fig. 3) serve the same purpose as the band valve 23 as they lock up the pressure
in the compartment d. In the case of the piston valve the pressure in the
compartment d forces the cup leathers 32" tight against the interior of the casing
and prevents leakage of pressure. Should the pressure be at any time greater in

page_text: the compartment c (Fig. 2) or b (Fig. 3) than in d then the cup leather 32ª and
the ball valve 35 respectively automatically open and allow pressure to pass
from c or 6 to d until the pressures are again equal. The use of a cup leather
piston, or the valve 35 and pipe 32, obviates the use of a hollow spindle as at
Fig. 1. In Fig. 3 it will be noted that I have shown an opening at 13* in the
valve seat and under the valve which may be used as a bye path passage instead
of or in conjunction with the hole 13.
In the modification shown at Fig. 5 the compartment d is placed in communication
with the atmosphere by the holes 38. In this case when the pressure in the com-
partment c is destroyed or reduced by the opening of the passengers' air or
"release" valve, the pressures at both sides of the diaphragm 9 are equalized and
the spring 5, which is, in this case, a powerful one, forces the diaphragm and
spindle 4 inwards and closes the controlling valve 3 which is normally kept open
against the action of the spring by the pressure of air in the compartment c acting
en the diaphragm 9. When the valve is closed the driver, can, as before explained,
again pump up the pressure and run to a place of safety.
It is to be understood that I can use in any of the constructions diaphragms in
lieu of pistons and vice versa. Likewise ball valves may be used in lieu of rubber
disc or ground metal valves and vice versa. I do not confine myself to any special
construction of valve.
Audible signals may be fitted in conjunction with the apparatus if so desired.
The parts of the apparatus may be variously modified without departing from
the invention.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. Train signalling or communicating apparatus for use in connection with
pressure "brake systems, wherein the opening of the passengers' air valve is
allowed to only partially destroy the pressure in the train pipes, the further
destruction of pressure being prevented by a self-acting controlling valve which is
so actuated by the fall of pressure as to cut off communication with the atmosphere
and thereby again close the brake system so that the engine driver can again pump
of the pressure to a sufficient extent to allow time to run the train to a place of
safety, substantially as hereinbefore set forth.
2. In pressure brake signalling systems, the application and use of a self acting
controlling valve and its accessory parts constructed substantially as hereinbefore
described and shown at Fig. 1 of the drawings annexed.
3. In pressure brake signalling systems, the application and use of a self acting
controlling valve and its accessory parts constructed substantially as hereinbefore
described and shown at Fig. 2 of the drawings annexed.
4. In pressure brake signalling systems, the application and use of a self acting
controlling valve and its accessory parts constructed substantially as hereinbefore
described and shown at Fig. 3 of the drawings annexed.
5. In pressure brake signalling systems, the application and use of a self acting
controlling valve and its accessory parts constructed substantially as hereinbefore
described and shown at Fig. 4 of the drawings annexed.
6. In pressure brake signalling systems, the application and use of a self acting
controlling valve and its accessory parts constructed substantially as herein before
described and shown at Fig. 5 of the drawings annexed.
7. The combination in pressure brake signalling systems of an automatic
" cut-out valve with a controlling valve, substantially as hereinbefore set forth.
Dated this 20th day of September 1893
H. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.