Year: 1893

page_text: Date of Application, 10th Oct., 1893-Accepted, 18th Nov., 1893
Figs. 6 and shew respectively the upper and Tower Sides of ULIC Γουανικό
valve,
Fig. 8 is a section of the valve casing on the line E. F. Fig. 3 and
Figs. 9, 10, 11, 12, 13 and 14 are part sections of the valve casing taken
respectively on the lines P, Q, R, S, T, U, shewing the arrangement of the ports
and passages.
The valve casing, in which are formed the various air passages hereinafter
described, instead of being made as formerly in two parts, the upper part containing
the rotating valve, and the lower part the piston, is, according to this invention,
made in one piece with the cavities for the rotating valve and the piston arranged
side by side, these cavities being tightly closed by two screw caps A and B.
Through A passes the valve spindle E, leakage past it being prevented by a packing
washer P. On the upper end of the valve spindle E is fixed the driver's handle D
which has in it a sliding piece d urged by a spring so as to press against the upper
edge of the valve box. This edge is formed with two projections did which by
stopping d determine the two extreme positions 1 and 5 of the handle D. There
is on the edge a hollow d and a wider hollow into which the sliding piece d
springs when the handle is in the position 2, and also in the positions 3 and 4, these
hollows causing a little resistance, which the driver can feel, to the movement of
the handle. On the lower end of the spindle E is a disc e from which projects a
wedge shaped piece e' fitting into a recess on the upper side of the rotating valve G
which can be turned by the handle D into the various positions 1, 2, 3, 4 and 5
indicated in Fig. 3 by the dotted radial lines.
The valve G has through it a hole U with a curved recess u in its under side
communicating with U, also a hole W through it; there is also in its under side a
large recess G¹, and a small curved recess Z. The face on which this valve bears
has a port G2 communicating with the passage V to the train pipe, a port G³
leading to the open air, with a curved recess 22 communicating with G³, a recess G¹,
a port W and a port Z. The space T above the valve G communicates with the
passage S leading from the main reservoir of compressed air. In the cylindrical
cavity covered by the cap B is fitted a piston H the stem I of whicb terminates in
a valve which, when on its seat J, closes a passage I¹ to the open air. From the
717

page_text: space above the piston H there is a passage Y communicating with the port Z.
This passage Y may also communicate with a small reservoir attached at A¹ to
constitute an extension of the space above the piston H, and thus to moderate its
action. The port W leads to the middle of a piston valve K which is urged to the
left by a spring O adjustable by turning a stem M having a screw thread, preferably
of rapid pitch so that a slight turn of the stem may make a considerable change in
the force of the spring O. Behind the piston valve K there is an outlet K* to the
open air, and from the chamber in front of its seating K', there is a passage X
leading to the upper part of the passage V. When signalling apparatus has to be
worked, the signalling pipe is attached at A2 which communicates with a port a².
The valve box is fixed to the engine by the stud and nut R.
The operation of the valve is as follows :-
:-
°
When the handle is in position 1, air from the main reservoir passes by S to the
space T, thence down through the hole U of the valve into the recess G₁ of the
seating, up into recess G¹ of the valve and down by V to the train pipe, which can
thus be fully and rapidly charged. But before it is charged to full working
pressure, the handle may be moved to position 2, cutting off the passage by U, and
then air will continue to flow by the small passage W past the valve K by X into V
continuing to raise gradually the pressure in the train pipe until it attains the full
working pressure which acting on the valve K overcomes the spring O causing K to
be seated. According as the spring O is adjusted to press with more or less force
on the valve K the pressure in the train pipe is greater or less. When the handle
is in position 3, the valve G closes all the ports in the scating below it. When the
handle is moved from 3 to 4, air escapes from above the piston H by the passage Y
and hole and recess Z'Z³ and by G³ to the open air, and, owing to the excess of
pressure then acting on the underside of the piston H, it rises, raising the valve I
and allowing air to escape by the passage I until the pressure in the train pipe is
so far reduced that the piston H descends. As in this operation the escape from
above H is by the small passage Z, the reduction of pressure in the train pipe is
gradual, and the driver can stop the discharge by moving the handle back to the
positions 3. When the handle is moved to position 5, the large cavity G¹ in the
valve puts the port G2 in communication with the port G³, and the air is then
rapidly discharged from the train pipe.
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 is: --
1. The construction of the valve casing in one piece with the valve and piston
cavities side by side closed by caps, substantially as described.
2. In the valve casing above referred to, the passages W and X and the piston
valve K, subject to pressure of a spring which can be adjusted to determine the
pressure in the train pipe, substantially as described.
Dated this 9th day of October 1893.
ABEL & IMRAY,
Agents for Applicant.