Improvements in Steam and other Fluid Pressure Engines.
Year: 1899

page_text: Date of Application, 7th Nov., 1893-Accepted, 9th Dec., 1899
COMPLETE SPECIFICATION.
[Communicated from abroad by THE AMERICAN WELL WORKS, a Corporation
organized under the laws of the State of Illinois, and having its place of
business at Aurora Kane County, Illinois, United States of America,
Manufacturers.]
Improvements in Steam and other Fluid Pressure Engines.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45, Southampton Buildings, in the County of Middlesex, do hereby declare the
mature 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 balanced slide-valves for engines, and has for its object
to provide new and improved means for cutting off the supply of steam from the
steam-chest to the cylinder in which the driving piston reciprocates, at any point
previously determined upon by the engineer.
Speaking generally, said invention consists in locating within a cylindrical
piston-valve two cut-off valves adapted to be moved independently of the motion
of the main valve, and adapted to regulate the supply of steam passing from the
steam-chest to the cylinder, the main-valve and the two cut-off valves therein
contained being suitably operated by eccentrics on the engine, in the ordinary
manner.
The said invention also contemplates the adjustment of the cut-off valves by a
governor of any approved pattern as usual, or by the hand of the engineer and
means are provided for such operation.
The accompanying drawing is a central longitudinal section through the steam-
chest and mechanism contained therein, showing also, in section, a portion of
the steam-cylinder and the piston therein.
1 indicates the steam-cylinder, 2, the piston in such cylinder, and 3 the piston
rod. 4 indicates the steam-chest, which for small sizes may he cast with the
cylinder 1, but which is preferably cast separate and bolted or otherwise suitably
secured to the cylinder. indicates a large steam inlet port in the upper part of
the wall of the chest 4 communicating with a wide passage 6 extending nearly the
full length of the chest and communicating with the interior of the chest at each
end. and 8 indicate heads for the opposite ends of the steam chest. 9 and 10
indicate cylindrical sleeves or liners located at opposite ends of the steam chest,
which are made to accurately fit the interior of such chest, and are for the purpose
of serving as seats for the main valve. Such seats are shown, as stated, to be in
the form of separate rings located within and secured to the steam-chest, but it is
obvious, of course, that such seats could be formed integral with the chest. Each
seat has formed in it a port, indicated respectively by 11 and 12, such poris being
of a size and character to properly cooperate with the ports in the main valve.
13 indicates the main valve which is cylindrical in shape and turned to fit
accurately within the chest upon the two seats 9 and 10, so as to be free to br
reciprocated. It has secured to one end a hub 14 to which is suitably connected
CD 9.77

page_text: one end of a stem 14", said stem projecting through the head 7 of the steam-
chest, a suitable stuffing-box being provided of course around said stem as usual.
In order to provide for the passage of another valve-stem, said stem 14 is made
in the form of a tube, as shown. The outer end of the stem 14° is connected in
any suitable way to an eccentric rod, not shown. In order to properly balance
the valve at all times, it, is, of course essential to provide for the free admission
of steam to all parts of the valve, and in order that it may be so admitted at the
end where the hub 14 is situated, said hub is made in the form of a spider, which, of
course, permits the steam to pass freely between the arms. At the opposite end
of the steam-chest is a plate 15, in which are formed wide openings through which
steam may pass. Inserted in the faces of this main valve 13 where they bear upon
the seats are suitable packing rings as shown, which may be of the form shown
or otherwise. 16 and 17 are ports formed in the main valve 13, near the opposite
ends thereof, and adapted to be brought over the ports 11 and 12 in the seats 9
and 10 respectively, which latter ports, as will be seen, register with other ports in
the steam-cylinder, so that through these several ports communication is estab-
lished between the chest and cylinder.
Within the main valve and uear each end thereof, are located two cut-off
valves, 18 and 19, each in the form of a ring from which arms extend to a central
hub, this construction permitting the free passage of steam throughout the steam-
chest, as stated when explaining the construction of the spider-like part 14. The
outer face of each cut-off valve is recessed and provided in the recesses with a
suitable metallic or other packing in order to ensure steam-tight joints between
such valves and the inner surface of the main valve. The central or hub portion
of each of these cut-off valves 18 and 19 is screw-threaded, one such central or hub
Fortion being given a right-handed screw-thread, and the other a left-handed
screw-thread. Passing through these cut-off valves is a long stem 20 which
extends through both heads of the steam-chest, extending out at one end through
the hollow valve-stem 14", which hollow stem fits accurately upon it, and where it
passes out at the opposite end it is surrounded by a suitable stuffing-box. The
end shown as passing out through the hollow valve-stem is suitably connected
to an eccentric to give the proper amount of reciprocation to such long stem 20
to cut off the steam at the desired point. Where such long stem 20 passes through
the hubs or central portions of the cut-off valves 18 and 19 it has formed upon it
screw-threads, as shown, to engage the interior screw-thrends of such central
portions or hubs, and, of course, such screw-threaded portions on the stem 20 are
oppositely inclined to adapt them for proper engagement with the right and left-
hand threads in the cut-off valves.
21 indicates a bracket extending from the head of the steam-chest, in the outer
end of which bracket is revolubly mounted a wheel 22, such wheel having formed
with it or suitably secured to it a sleeve or elongated hub 23 that fits over the end
of the stem 20, the said sleeve and stem being secured together by a feather or
key as shown, or in any other suitable manner. Lock nuts on the inner end of the
elongated hub are employed as shown, to hold such hub and its wheel in place.
To insure the main valve reciprocating perfectly true, I provide a guide on its
outer face where indicated at 24, in which a suitable projection on the inner face
of the steam-chest engages. Such projection may be, if desired, one or more
bolts inserted through the side wall of the chest, and having the inner end or ends
thereof enter or engage such guide. I also provide a guide to ensure the same
perfection of reciprocation in a straight line without side turning for the cut-off
valves 18 and 19, the means employed for this purpose being a rod 25 secured at
one end in a cross-piece 26 at one end of the main valve and having its opposite
end fitting in an opening 27 in one of the spokes of the hub 14, in which opening
it is free to move back and forth.
28 represents an indicator adapted to indicate on a suitably marked plate (not
shown) at what point in the stroke of the engine the steam is cut off by the cut-off
valves 18 and 19.

page_text: In operation, with the parts as shown in the drawing, stenm admitted through
the port
will pass into the centre of the main valve from each end by way of
the passage 6, and to the cylinder 1 by the ports 16 and 11 is the main valve
and its seat 9 respectively, and the communicating port in the cylinder, the steam
being cut off by the valve 18 at such point as may have been previously determined
upon by the engineer, and the setting of such valve and its companion valve 19
to attain this object being accomplished by the turning of the stem 20, the effect
of which will be to draw the two valves 18 and 19 toward each other, or move them
farther apart by reason of their screw-threads inclining in opposite directions.
This adjustment of the valves to cut off the steam is done through the turning of
the wheel 22, to the hub of which the stem 20 is keyed, and such turning may be
done directly by the engineer, or through the medium of suitable gearing operated
by an ordinary governor
As the pisten 2 is driven forward in its cylinder 1 and approaches the end of
its stroke, the main valve, through the action of the eccentric which controls it,
is reversed, the supply of steam cut off through the ports 16 and 11, and the
corresponding poris at the opposite end brought into communication so as to admit
steam to the cylinder at the opposite side of the piston. While the main valve is
working as described, the cut-off valves are also being reciprocated by the action
of a separate eccentric to which the steam 20 is connected, and are timed so that
their motion will be ahead of the main valve and will cut off the supply of steam
to the ports 16 and 17 as desired, the point at which the cutting off is to be
effected being determined by the adjustment of such valves farther from or nearer
to each other,and as stated, such adjustment is made by the turning of the stem either
automatically by a governor, or by the hand of the engineer. By the arrangement
of the cut-off valves within a cylindrical main valve, and providing for the pres-
sure of steam at all points in such main valve, a perfect balancing of the valves
is attained, so that the adjustment for cutting off at any desired point may at any
time be readily and quickly made, and just the required amount of steam admitted
through the main valve to the cylinder 1, so that the expansion of the steam may
be properly utilized.
The steam is exhausted through the same ports in the cylinder, steam-chest and
valve-seats by which it enters, passing away through a suitable exhaust passage,
as clearly apparent from the drawing.
While I have herein described the invention as intended for use in regulating
the supply of steam, I would say that I do not wish to be confined to steam, as it
is also applicable to air or gas, or other lluids used under pressure for driving an
engine.
Having now particularly described and ascertained the nature of this invention,
and in what manner the same is to be performed, as communicated to me by my
foreign correspondents, I declare that what I claim is :-
1. The combination with a steam cylinder and piston therein, and a steam-chest
having communication with said cylinder, of a cylindrical main valve in said
steam-chest adapted to be reciprocated in unison with the movement of an engine
driven by the steam in said cylinder, and two cul-off valves seated in the main
cylindrical valve and adapted to be operated by the said engine independently of
the operation of said main cylindrical valve, and also adapted to move ahead of the
said main valve to cut off the supply of steam at any predetermined point, sub-
stantially as specified.
2. The combination with a steam cylinder and piston therein, and a steam-
chest having communication with said cylinder, of a cylindrical main valve in said
steam-chest adapted to be reciprocated in unison with the movement of an engine
driven by the steam in said cylinder, two cut-off valves seated in the main cylin-
drical valve, means for moving said cut-off valves to and from each other to cut off
the steam at such point as desired, and means for reciprocating said cut-off valves
independently of the main valve and ahead of the movement of the main valve,
substantially as specified,

page_text: 3. The combination with a steam cylinder and piston therein, and a sicam-
cheat having communication with said cylinder, of a cylindrical main valve in
said steam-chest adapted to be reciprocated in unison with the movement of an
engine driven by the steam in said cylinder, and open at both ends to admit steam
for balancing purposes, two cut-off valves seated in said main cylindrical valve.
a stem passing through said cut-off valves and connected to them by right and
left hand screw-threads respectively, and adapted to be connected at one end to an
eccentric for reciprocating said stem and cut-off valves, and having a wheel at the
other end for turning said stem to adjust the cut-off valves nearer to or farther
from each other, substantially as and for the purpose specified.
Dated this 7th day of November 1899.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.