Improvements in Steam-engine Slide Valves.
Year: 1894

page_text: Da'e of Application, 27th Nov., 1894-Accepted, 13th July, 1895
COMPLETE SPECIFICATION.
Improvements in Steam-engine Slide Valves.
We, EMIL LOUIS SAUER and ALBERT COLEMAN, both of 2291 West Randolph
Street, Chicago. Illinois, United States of America, Artisans, 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 in that class of valves that are especially
adapted for use in connection with locomotive engines, and has for its object to
provide the ordinary slide-valve with an improved arrangement to relieve the
piston from any undue compression or back pressure.
In the drawing :-
:-
Figure 1 is a broken-away longitudinal section of a cylinder and steam-chest
showing the valve in position; the piston being in elevation.
Figure 2 is a similar view; the piston and valve being shown in a different
relative position.
Figure 3, an end elevation of a slide-valve and its yoke; the valve-rod being
broken away.
Figure 4, a top or plan view of the valve.
Figure 5, a bottom plan.
Figure 6, part side elevation and part section of the valve; the section part
being in two different planes X, Z, Figs. 4 and 7.
Figure 7, a transverse section on line 7, Fig. 6; and
Figure 8, a detached detail of a locking-ring.
A is the slide-valve, A' the valve-yoke, A³ the valve-rod, A³ the steam-cheet,
B the cylinder, B' the piston, and B' the piston-rod.
As the cylinder, piston and steam-chest are of the usual ordinary construction
the description will be limited to the improved valve.
The side-walls of the valve are provided with a number of apertures a opening
horizontally therethrough. In each of these apertures is inserted a fixed bushing a¹
of cylindrical form. The inner ends of these bushings open into the exhaust-
chamber D; the outer ends being closed by a flanged head a² which bears against
the exterior surface of the valve and prevents the bushings from entering too far
when inserted in place, as shown in Figs. 1, 2, and 7.
The bushings are provided near their inner ends with an annular exterior
groove a. The adjacent valve-surface is provided with a corresponding groove a*.
An open spring-ring b (Fig. 8) is seated in said groove and serves the purpose of
assisting in locking the bushings in position against an outward endwise movement.
The bushings are located directly opposite each other and have piston-valves d do
inserted therein; each pair of which is mounted on the respective ends of a common
rod d' extending across the exhaust-chamber of the main valve.
The piston-valves are adapted to have a limited reciprocating endwise
movement.
The bushings are provided with a number of exhaust-ports d², which open on one
side into the annular space d', (Fig. 6), and exhaust through the open ends of the
bushings into the exhaust-chamber of the main valve, as indicated by the arrows in
Figs. 1 and 2.
The annular space in the adjacent valve-surface around the bushings provides
for a free and quick escape, as the exhaust is distributed to the different ports
alike.

page_text: The main-valve is provided with the steam-port g (Fig. 5) starting in from the
underside and opening into the closed (Fig. 6) ends of the bushings back of the
piston-valves. This end of the piston-valves is beveled or rounded off, as at g', so
that the steam can enter and force the same over to their opposite position.
The rectangular exhaust-ports 92 alternate with reference to the steam-ports,
Fig. 6, and open into the steam-port or passage g, as indicated by dotted oblique
lines g³, Fig. 7.
arrow.
E E are the usual steam-passages connecting the steam-chest and cylinder.
Supposing the piston (Fig. 1) to be moving in the direction indicated by the
The valve moving in the opposite direction has just closed the steam-
passage E and opened up the ports g, which admit steam back of the piston-valves
and force the same over to the position shown, that is, in the direction in which the
piston is moving. This opens the exhaust or relief-ports in the bushings on that
side; the piston-valves d covering and closing the companion-ports on the opposite
side.
Now, when the piston is near the end of its stroke (Fig. 2) and the valve has
traveled far enough to open the narrow exhaust-ports g2, the pressure, back of the
piston-valve d, will be relieved and escape down into the passage E¹ leading to
the cylinder; the excess of pressure, entering back of the piston-valves d, forces
the same over to their other position, shown in Fig. 2, thus relieving the piston
from compression or back-pressure which escapes into the exhaust-chamber through
the ports in the circular wall of the bushings, which are alternately opened and
closed.
The steam-ports y in the under side of the valve, which lead into the bushings
back of the piston-valves, are much wider than the alternating exhaust-ports, which
provides for the admission of steam while the valve is moving the required distance
before the alternating exhaust-ports are uncovered to relieve the pressure on the
piston-valves on that side.
The adjustment of the piston-valves is such that they are automatically shifted
from side to side in accordance with the direction in which the main valve and
piston are moving, so that there will be little, if any, compression on the exhaust-
side and no waste of steam-force on the acting side.
If at any time the conditions should require it, the steam-ports may be enlarged
toward the outer ends so that the live steam may act on the series of piston-valves
without always depending on compression.
Any number of piston-valves may be used, one or more, as practical working may
require.
The connecting-rods may be made in two parts and joined in the center by means
of a screw-threaded sleeve, to facilitate insertion and removal from the main-valve
without being compelled to take out the bushings.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim, is―
1. A steam-engine valve, provided in its respective sides with a number of
apertures, bushings, seated in said apertures and open at one end and closed at the
other and having exhaust-ports in the sides, piston-valves, inserted in and having a
reciprocating movement in said bushings and connected by rods extending
across the exhaust-chamber, and steam-ports or passages, starting in from the
bottom of the maiu-valve and communicating with said bushings, substantially as
set forth.
2. A steam-engine valve, having steam and exhaust-passages starting in from the
bottom and stopping short in the respective side walls, bushings, seated in the side-
walls and provided with exhaust-openings, piston-valves, adapted to have a
reciprocating movement in said bushings, in accordance with the movement of the
main valve, substantially as set forth.

page_text: 3. The combination with the bushings, having an annular exterior groove, the
main-valve, having a corresponding groove in the adjacent surface, and a spring-
ring inserted in said grooved parts and locking said bushings in place, substantially
as set forth.
Dated this 27th day of November 1894.
EMIL LOUIS SAUER.
ALBERT COLEMAN.
Haseltine, Lake & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicants.