IMPROVEMENTS IN OR APPLICABLE TO VACUUM BRAKE APPARATUS
Year: 1880

page_text: LETTERS PATENT to James Gresham, of the Firm Gresham and Craven, of
Craven Iron Works, Salford, in the County of Lancaster, Engineers and
Machinists, for an Invention of "IMPROVEMENTS IN OR APPLICABLE TO
VACUUM BRAKE APPARATUS."
PROVISIONAL SPECIFICATION left by the said James Gresham at the Office
of the Commissioners of Patents on the 9th November 1880.
JAMES GRESHAM, of the Firm Gresham and Craven, of Craven Iron Works,
Salford, in tho County of Lancaster, Engineers and Machinists. "IMPROVEMENTS
IN OR APPLICABLE TO VACUUM BRAKE APPARATUS."
Firstly. My Invention relates to valves for automatic vacuum brakes similar to
those described under the first head of the Specification of Letters Patent granted
to me, No. 4801, and dated the 26th day of November 1878, and refers more
particularly to that modification of automatic valves illustrated by Figs. 3 and 4
of the Drawings accompanying the said Specification.
My present improvements consist in forming the main valves with a hole through
the axis of the connecting stem or guide, which hole is made small at one end, aud
is formed with a seating so as to be closed by an india rubber or other ball valvo
when atmospheric pressure is admitted in to the "train pipe," or pipe passing from
end to end of a train. When a partial vacuum is formed in the "train pipe
ball valve moves away from its seating, and air can thon be drawn from the vacuum
chamber.
the
Secondly. My Invention relates to improvements upon those also described
under the first head of the Specification of the said Letters Patent, having referenco
to arrangements by which automatic vacuum brake apparatus can be readily
changed so as to be worked as a "simple vacuum brake," and my present improve-
ments are also intended to dispense with the valve hitherto used with automatic
vacuum brakes for taking the brakes "off" when the vehicle is detached by
admitting the atmosphere into the brake cylinder.
My present improvements consist in arranging pipes from the "train pipe," the
automatic valve, the vacuum chamber, and brake cylinder, and combining them

page_text: "
with a cone cock or slide or disc valve having ways, ports, and passages arranged
so that when the cock or valve is moved into one position communication will be
open between the train pipe and the automatic valve and the vacuum chamber,
and with that valve and the brake cylinder when the brakes are to be "put on;
and when the cock or valve is moved into another position the "train pipe" will
be put into direct communication with the brake cylinder, and the communication
with the automatic valve and the vacuum chamber, and between the latter and
the brake cylinder, is shut off, and when the cock or valve is moved to a position
between the two above named positions the apparatus is put out of action both as
an "automatic" and "simple vacuum," and is disconnected from tho train pipe.
When the vehicle is uncoupled from a train the brake is or may be taken "off" by
moving the cock or valve to the position for "simple vacuum," which will admit
the atmosphere into the brake cylinder, and by moving the cock or valve one
way or the other the brakes may be put "on ог "off" as long as there is a
sufficient partial vacuum remaining in the vacuum chamber. The above
explanation refers to vacuum brakes in which the atmosphere is constantly acting
on one side of the diaphragm or piston of the brake cylinder, as illustrated by
Figs. 26 to 29 inclusive of the Specification of my aforesaid Patent.
In the case of vacuum brakes, where a vacuum is formed on both sides of the
diaphragm or piston of the brake cylinder, which is caused to operate when the
equilibrium is destroyed, by admitting the atmosphere to the cylinder on one
side of the piston or diaphragm; my present Invention is equally applicable by
providing in the cock or valve another way, port, or passage to admit the
atmosphere into the brake cylinder on one side of the diaphragm or piston.
"
Thirdly. My improvements relate to the arrangements for showing when "simple
vacuum brakes aro not in proper working order described under the second head
of the Specification of my aforesaid Letters Patent, and consists of an improved
arrangement and construction of pressure guage or "tell tale," which I prefer to
construct of a diaphragm arranged in a plane parallel with the vertical face upon
which the index is formed.
The movements of the diaphragm are transmitted through a chain or cord, or
through a bell crank lever and rods, or other means, to the index hand, or through
a rod and lover which is forked or slotted to act upon a helix formed on the axis
of the index hand. The force acting on the diaphragm is counteracted by a spring
or springs.
"
Fourthly. My Invention relates to improvements in the cock or valve for
putting automatic brakes "on and "off" which is illustrated by Figs. 19, 20,
and 21 of the Specification of the said Letters Patent, and consists in substituting
in place of the cock therein described a dise valve with ports and passages.
Fifthly. My Invention relates to the automatic couplings for vacuum brakes
described in the Specification of Letters Patent granted to me, numbered 392,
dated 29th January 1880, and consists in simplified modifications intended to
prevent the couplings from being improperly connected or disconnected, and in
dispensing with springs and inclines described in the said Specification.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Gresham in the Great Seal Patent Office on the 7th May
1881.
JAMES GRESHAM, of the Firm Gresham and Craven, of Craven Iron Works,
Salford, in the County of Lancaster, Engineers and Machinests. "IMPROVEMENTS
IN OR APPLICABLE TO VACUUM BRAKE APPARATUS."
Firstly. My Invention relates to valves for automatic vacuum brakes similar to
those described under the first head of the Specification of Letters Patent granted
to me, No. 4801, and dated the 26th day of November 1878, and refers more
particularly to that modification of automatic valves illustrated by Figs. 3 and 4 of
the Drawings accompanying the said Specification.
My present improvements consist in forming the main valves with a hole through
the axis of the connecting stem or guide, which hole is made with a seating so as
to be closed by an india rubber or other ball valve (a brass ball valve by preference)
when atmospheric pressure is admitted in to the "train pipe," or pipe passing from
end to end of a train.
"
When a partial vacuum is formed in the "train pipe the ball valve moves
away from its seating, and air can then be drawn from the vacuum chamber.
Secondly. My Invention relates to improvements upon those also described under
the first head of the Specification of the said Letters Patent, having reference to
arrangements by which automatic vacuum brake apparatus can be readily changed
so as to bo worked as a "simple vacuum brake," and my presont improvements are
also intended to dispense with the valve hitherto used with automatic vacuum
brakes for taking the brakes "off" when the vehiclo is detached by admitting the
atmosphere into the brake cylinder.
My present improvements consist in arranging pipes from the "train pipe," the
automatic valve, the vacuum chamber, and brake cylinder, and combining them
with a cono cock having ways, ports, and passages arranged so that when the
cock or valve is moved into one position communication will bo open between
the train pipe and the automatic valve and the vacuum chamber, and with that
valve and the brake cylinder, when the brakes are to be "put on," and when the
cock or valve is moved into another position tho train pipe will bo put into direct
communication with the brake cylinder, and the communication with the automatic
valve and the vacuum chamber, and between the latter and the brake cylinder is
shut off, and when the cock or valve is moved to a position between the two above
named positions the apparatus is put out of action, both as an automatic and
simple vacuum, and is disconnected from the train pipe.
When the vehicle is uncoupled from a train the brake is or may be taken "off"
by moving the cock or valve to the position for " simple vacuum," which will
admit the atmosphere into the brake cylinder, and by moving the cock or valve one
way or the other the brakes may be put "on" 'or "off" as long as there is a sufficient
partial vacuum remaining in the vacuum chamber.
"
The above explanation refers to vacuum brakes in which the atmosphere is
constantly acting on one side of the diaphragm or piston of the brake cylinder, as
illustrated by Figs. 26 to 29 inclusive of the Specification of my aforesaid
Patent.
In the case of vacuum brakes where a vacuum is formed on both sides of tho
diaphragm or piston of the brake cylinder, which is caused to operate when the
equilibrium is destroyed by admitting the atmosphere to the cylinder on one side
of the piston or diaphragm; my present Invention is equally applicable by pro-
viding in the cock or valve another way, port, or passage to admit the atmosphere
into the brake cylinder on one side of the diaphragm or piston.
-

page_text: Thirdly. My Invention relates to improvements in the cock or valve for putting
automatic brakes "on" and "off," which is illustrated by Figs. 19, 20, and 21 of the
Specification of the said Letters Patent, and consists in adding a small valve to
slowly admit the atmosphere into the vacuum chambers and cylinders for the sacks
or diaphragms when required to take "off" the brakes and prevent them from being
applied when the train is to be detached from the engine.
Fig. 1 is a longitudinal section; Fig. 2 a cross section on the line A, B, Fig. 1,
and Fig. 3 is an outside plan view of the improved valve apparatus according to
the first part of my Invention.
a is the branch pipe from the train pipe; b, the branch to the vacuum chamber;
c, the branch pipe to brake sack or cylinder; d is the main valve; c, the diaphragm
connected with the main valve; f, holes in the casing to admit the atmosphere to
one side of the diaphragm (e), and through the main valve to the pipe c leading to
the brake sack or cylinder.
It will be seen that the stem or spindle of the double valve d is tubular, and one
end is enlarged and has a seating formed in it for a ball valve a³ which is prevented
from moving too far from the seating by a pin a¹, as shown.
This valve apparatus is used with the longitudinal axis of the main valve d in a
horizontal position, as shown, so that the ball valve a will fall away from its
Beating by gravity, this ball valve being formed by preference of metal, so that it
will have weight enough to resist the action of such small currents of air as arise
from the slow variations in the perfection of the partial vacuum, but will be readily
acted upon by the strong current which is formed when the brakes are to be put
on. Fig. 4 is a longitudinal section, and Fig. 5 is an outside view of an improved
modification of the valve illustrated by Figs. 6 and 7 of the Specification of my
aforesaid Patent for opening and closing the communication between the train pipe
and vacuum chamber. a is a branch to the train pipe; b, pipe to vacuum chamber;
a³, a metal ball valve having its scating in the casing, and a' is a pin to limit the
movement of the ball valve; g is a stem or spindle sliding in guides in the bush g³,
which spindle has a screw thread for an arm g* screwed upon the spindle g, which
secures a diaphragm g' between the arm g* and a collar on the spindle g, the
outside edge of the diaphragm (g) being secured by the bush g³ carrying the
spindle, as shown.
The lower end of the arm g* is so formed that it will come against and push the
ball valve a away from its seating when a communication is to be opened between
the train pipo a and the pipo b to the vacuum chamber, when the spindle is
moved end ways by the double lever g jointed to the end of the spindle g when
moved on its fulcrum or joint pin g³ in either direction.
This valve apparatus is intended to be used with the longitudinal axis of the
spindle in a horizontal position (as shown), so that the ball valve a will, when
required, fall away from its seating by gravity.
Fig. 6 is a cross section, and Fig. 7 an outside view of a four way cock arranged
according to one modification under the second part of my Invention, the appli-
cation of which is further illustrated by Fig. 11, which is an elevation of the
connected parts, with the cock, and its ways shown in section.
Fig. 8 is a cross sectional view, and Fig. 9 a longitudinal section of a cock,
according to the other modification, under the second part of my Invention, the
application of which is further illustrated by Fig. 12, an elevation of the connected
parts with the cock and its ways, shown in section.
In Fig. 11 a* is the train pipe and the branch from it; c, the cylinder of the
brake sack or diaphragm upon which the atmosphere is constantly acting on the
under side of the diaphragm; bx, the vacuum chamber; , the automatic valve
apparatus, (see Figs. 1, 2, and 3). a is the pipe between the automatic valve x and
the train pipe a* through the cock; b, the pipe between the valve x and the
vacuum chamber bx, and c the pipe between the valve x and the cock, and through
it and the pipe c' to the cylinder c
The cone or plug of the cock is shown in Figs. 6 and 11 in the position, when