Improvements in Cut-off Valves for Steam Engines.
Year: 1892

page_text: Date of Application, 24th June, 1892-Accepted, 6th Aug., 1892
COMPLETE SPECIFICATION.
Improvements in Cut-off Valves for Steam Engines.
We GIDEON VANBUREN PUTMAN of No. 7 Third Street Gloversville in the
County of Fulton in the State of New York United States of America Engineer
and LAWTON CATEN of 87 South Main Street Gloversville in the County of
Fulton in the State of New York United States of America Railroad Superinten-
dent 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 a cut-off valve adapted to be used on stationary engines
as well as on locomotives.
And the invention consists in a novel construction of said cut-off valve whereby
the same is rendered very sensitive and very efficient in its operation, all as herein-
after more fully described and set forth in the claims.
In the annexed drawing
Fig. 1 is a side view illustrating one of the modes of applying my improved
cut-off valve to a stationary engine,
Fig. 2 is an enlarged longitudinal section of the cut-off valve,
Fig. 3 is a transverse section on line a, a, in Fig. 2, and
Fig. 4 is an enlarged perspective view of the so-called speeder.
Similar letters of reference indicate corresponding parts.
A represents the steam chest of the cut-off valve, which steam-chest we preferably
make of cylindrical form as shown. It is secured either to the top or side of the
main-valve steam chest C which is provided with the usual valve by which steam
is admitted to and emitted from the cylinder D of the engine in the usual and well
known manner not necessary to be illustrated.
P denotes the steam pipe by which live steam is admitted into the cut-off valve-
chest A which is provided in its side with two steam ports a a by which it
communicates with the interior of the main valve-steam-chest C.
In the chest A are arranged two cylindrical throttling slides b b which are of
the same or nearly the same diameter as the interior of said chest and movable
toward and from each other. Each of said slides is provided with a steam-port c
in the side adjacent to the ports a a, and a sufficient distance from the inner end or
end adjacent to the companion slide to form a bridge d.
Each of these throttling slides has attached to it à separate rod e and the two rods
extend through one and the same end of the chest A. and are connected to opposite
ends of a centrally pivoted lever 7. The pivotal support may be a bracket l' on the
governor stand as shown. When the throttle valve is applied to a stationary engine
the said lever is suitably arranged to be operated by a suitable governor g driven by
the engine, but when connected to a locomotive the lever is to be operated by another
lever suitably connected thereto and under control of the engineer. By operating
the lever the two throttling slides are caused to move either toward or from each
other and thus carry the ports cc of said slides to a greater or less degree in or
out of communication with the ports a a of the chest A and consequently the
admission of steam to the main valve steam-chest is varied in volume. This is
effected automatically by the governor y which in its dormant position holds the
lever so as to cause the throttling slides to stand with their ports c c directly
over the ports a a of the chest A, and when the engine is in motion the governor y
turns the lever so as to carry the throttling slides toward opposite ends of the
chest A to a greater or less distance according to the velocity of the governor, and
said movement of the throttling slides carries the ports thereof to a corresponding
degree out of communication with the ports a a, the steam being thereby cut off

page_text: or partly cut off from the main valve steam-chest and the speed of the engine is:
checked.
We prefer to employ in connection with aforesaid throttling slides and governor,
a speeder S by which the said slides are caused to open the ports a a to a greater
degree and thus cause the engine to move at a higher speed. Said speeder consists
of the quadranth which is rigidly secured to the same shaft to which the lever lis
affixed. Said quadrant is provided with a segmental slot and to the axis of the
quadrant is pivotaly connected an arm which extends across the quadrant and is
connected to the spindle of the governor g.
A post is pivoted to the quadrant and formed with a screw threaded sleeve k¹
through which passes a screw coupled to the arm j so as to allow the latter to be
set at any desired angle by means of said screw. A clamping screw u passes through
the arm and slot of the quadrant and serves to clamp said arm in its adjusted
position.
It will be observed that, by setting the arm into different angles, the quadrant h
and lever are also carried into different angles, and by that means the throttling
slides can be caused to open the ports a a to a greater degree when desired to
accelerate the motion of the engine.
Within the throttling slides is located a cylindrical slide-valve f preferably
composed of two cylinders rigidly secured to one and the same stem and a proper
distance apart to form between them a steam port i of about the same width as the
bridge a between the ports a a of the chest A. The valve-stem " extends through
the end of the chest A. and is connected to an eccentric secured to the main shaft
or crank-shaft o of the engine.
The connection of the stem f¹ with the said eccentric may be made in various
ways, one of which is indicated by the lever and eccentrie rod in Fig. 1 of the
drawing. The valve thus has a uniform stroke and the throttling of the steam
is effected by the movement of the slides b b.
In order to balance the described throttling valve, I form the interior of the
chest A with circumferential grooves in line with the ports a a to allow the
steam to circulate between the slides and valve f, and I perforate the beads of
the throttling slides b, and also the diaphragms ss of the valve f to which the
stem is attached, to allow steam to pass to the ends of the chest A.
pressure of the steam on the throttling slides and cut-off valve is thus
equalized as near as possible, and consequently wear and tear is greatly obviated.
The
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. In combination with the main valve steam-chest of an engine, a cut-off valve
chest receiving the live steam and provided with steam ports communicating with
said steam-chest, throttling slides seated movably toward and from each other
within the cut-off valve-chest and provided with steam-ports and bridges at their
adjacent ends, rods extending from the throttling slides, a centrally pivoted lever
connected at opposite ends to said rods to regulate the throttling, and a cut-off'
valve placed movably over the ports of the throttling slides and actuated by the
motion of the engine as set forth.
2. In combination with the main valve steam-chest of an engine, a cut-off valve
chest of cylindrical form receiving the live steam and having in its side steam ports
communicating with the main steam-chest, two cylindrical throttling slides in said
cut-off valve-chest and of the same or nearly the same diameter and provided each
with a steam-port in its side and with a bridge at its inner end, two rods extending
.respectively from the two throttling slides through one and the same end of the
cut-off valve-chest, a centrally pivoted lever connected at opposite ends to the said
rods to move the slides simultaneously in opposite directions, a governor actuating
said lever, a cylindrical slide-valve located in the throttling slides and provided
in its side with a port of about the same width as the bridge between the ports of

page_text: the cut-off valve-chest, a rod extending from said valve through the end of said chest,.
and receiving reciprocating motion from the engine as set forth.
3. The combination of the cut-off valve-chest A, of cylindrical form and provided
with the ports a a and circumferential grooves r, the cylindrical throttling
slides having perforated heads, and the valve f having perforated diaphragms & s
substantially as described and shown.
4. In combination with the governor and the throttling slides having separate
stems extending through one and the same end of the valve-chest, the lever / and
quadrant attached to one and the same shaft and said lever connected at opposite
ends to the aforesaid stems, the arm pivoted to the axis of the quadrant and
having its free end connected to the governor spindle, and the screw a for adjusting
the arm in its position as set forth.
Dated this 10th day of June 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicants.