An Improved Double Cylinder Direct Acting Steam Engine.
Year: 1889

page_text: e of Application. 14th May. 1889-Accepted. 15th June, 1889
COMPLETE SPECIFICATION.
An Improved Double Cylinder Direct Acting Steam Engine.
I, WILLIAM DAVIS HOOKER, Hydraulic and Mechanical Engineer, of St Louis, in
the state of Missouri, United States of America, 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 :-
My invention relates to double cylinder direct acting steam engines, and has for its
object the provision of a simple and effective engine of this type.
The following detailed description will fully explain the nature, construction and
functions of my said invention, and the manner in which I carry the same into
practice.
The accompanying drawings illustrate what I consider the best means for carrying
my said invention into use.
Figure 1 is a plan view of both cylinders, with the valve chamber removed, showing
the main valve seat, ports, etc.
Figure 2 is a vertical section of the engine on the line cc, Fig. 1, showing the valve
chamber mounted over the cylinders.
Figure 3 is a transverse vertical section of the invention taken on the line a a,
Fig. 1. This view shows the valve chamber also, but at right angles to Fig. 2.
Figure 4 is a longitudinal section on line xx, Fig. 3, parts being taken on different
vertical lines, as the line indicates.
Figure 5 is a face view of the main valve comprising the D and B types.
Figure 6 is a transverse section of the same, on the line ii Fig. 5..
Figure 7 is a section on line hh, h. of Fig. 5.
Figure 8 represents a section of supplemental valves for controlling the admission
and exhaust of steam to the valve chest, or chamber. This Figure is represented in
relative position with Figure 4, to indicate the position of the valve at a certain point
of operation.
Figure 9 is a face view of the valve shown in Figure 8.
Figure 10 is a face view of a modified form of main valve, having two cavities of
the D type.
Figure 11 is a transverse section of Figure 10, taken across one of exhaust
cavities.
Similar letters of reference indicate corresponding parts in all the figures where
they occur.
A represents one cylinder, and B the other, of my double cylinder direct acting
engine. They are connected by yokes A' B' to a pump (not shown), and the piston
rods A B² of the cylinders A B serve also as pump rods.
C is the valve chest, or chamber, mounted over the cylinders in the manner and
position shown. In it is one valve seat, and one valve for controlling the admission
and exhaustion of steam to and from both cylinders. The valve seat is marked D,
and the main valve which moves upon it is marked E. The valve is moved by
means of a recessed piston J. between the two parts jj to which the valve E is held.
The piston J is operated by steam the admission and exhaustion of which are controlled
by a supplemental valve k, which is moved by a rod K, connected to a valve gear K',
on the yoke A', and operated by rod K2, connected to and driven by tho piston
rod A of the cylinder or engine A, which, for distinction and convenience I
denominate the main or controlling cylinder of the engine, since from it the one
valve which controls the admission of steam to both cylinders, derives its sole
operation and control, while cylinder B, I term the secondary cylinder.
It will thus be seen that the pistons of both cylinders or engines are driven by
motion derived from the pistons of one cylinder only, which feature I, deem to be
novel and important.

page_text: The valve gear K is of any suitable type.
Referring now to the construction of parts a, a', and b, bare the main steam
ports leading from the main valve seat D to the steam cylinders A and B ; the
ports a leading to the main cylinder A, and the ports a leading to the other
or secondary cylinder B, and opening into said cylinders a little distance from each
end thereof, as shown.
c, c, and d, d', are secondary steain ports also leading from the main valve D, but
extending to the extreme end of the respective cylinders A and B. e, e¹, are the
exhaust ports leading from the main valve seat to the main exhaust passage, which
is common to both cylinders. These exhaust ports e, el connect only with the
main steam ports a, a, b, b¹ and the secondary ports c, c', d d have no exhaust
connection.
And the steam ports a, a, b, b¹ and the secondary steam ports c, c, d, d¹ are ali
separate and have no connection with each other. They all lead into one single
valve scat.
The main valve E is one single valve, but may comprise both the D & B types of
valves, or the D type only, but have two cavities. The D and B types are both
shown on the valve, Figs. 5, 6 and 7, and when this style of main valve is used
upon an engine having the two cylinders and valve seat above described, the effect
will be to drive the pistons of the two cylinders in opposite directions at the same
time.
With the D & B types combined in one valve, I also place narrow transverse
cavities in the valve E and openings or cuts p p on the sides thereof.
The D type alone is shown in Figures 10 and 11, but two cavities are used one in
each end of the valve, and the effect of the use of this style of valve upon the
cylinders and valve seat described, is to drive the pistons in both cylinders in the
same direction at the same time.
As the piston in the main or controlling engine or cylinder A nears the end of
its stroke, it will through the valve movement K attached to its piston rod and
supplemental valve k, cause the main valve to be reversed by the steam pressure, as
will be herein after explained.
Since the secondary steam ports c c and d d supply the live steam to the engines;
but have no exhaust, it will readily be seen that all the steam which is removed from
the cylinders must be exhausted out of the main ports under the cavities of the main
valve through separate exhaust ports e and e¹ to the common exhaust passage ; and
that, as the main pistons close the main steam ports in their respective cylinders,
some distance from the ends of their strokes the pistons will be cushioned on
'compressed exhausted steam or air, remaining in the ends of the cylinders and
unable to escape from the ports c c and d d. This construction and arrangement
gives a very efficient and reliable cushioning device, and one which can be regulated
as to amount of retained'air or steam, by placing the mouths of the main or
secondary steam ports closer to or farther apart in the cylinders: All noise and
concussion are obviated and the pistons are brought to rest or slowed down more
gradually upon this exhausted steam, than it could be with live steam supplied for
the purpose as is often done.
Since only one engine or "cylinder gives or controls the valve movement, and since
the prime object of the double cylinder direct acting engine is to produce a steady
pressure on the discharge of the pumps they are called upon to operate, it is very
desirable that otie engine shall arrive at the end of its stroke slightly in 'advance of
the other, so as to gradually slow'down, giving the pump valves in the pump it is
driving, time or opportunity to seat quietly, and also that both engines shall make
their full stroke before the engine entirely stops or reverses. To accomplish this end
and have both engines under perfect control while running I have invented and
applied a controlling valve or device which 1 place in the main exhaust passage
between the discharge openings of the separate exhaust ports of the two engines.
This valve or device is marked g and is clearly shown in Fig. 3 of the drawings. It
consists of a plate mounted upon a screw rod i which is supported at one'endins
....

page_text: bearing in the walls of the exhaust port and at the other passes through a stuffing
box and is provided with a hand wheel h on its outer end. By turning the rod i
in one direction or the other the plate or valve is carried to one side or the other
broad wise across the exhaust passage f; and the movement of the plate g being
produced by a screw it is very easy and gradual, and the adjustment of the plate can
be controlled witli great nicety, and the slightest perceptible change in the com-
pression of the exhaust can be produced. It is also apparent that the plate g may he
moved up tight against the exhaust of secondary engine B and close it, so that the
main engine A can be run alone as a single cylinder engine.
When engine A is running itself and also supplying and exhausting steam to and
from engine B, it is very desirable to have the piston of engine B arrive at the ends
of its strokes slightly in advance of the piston of engine A for the reasons above
stated. And this can be caused by turning the hand wheel which moves or draws the
plate or regulating device slightly towards the mouth of exhaust of engine A, the
motion whereof thereby retarded by the compression of its exhaust and piston of
engine B will arrive at the end of its stroke and cushion and slow down in advance of
engine A. Or, it engine B is running too far ahead of engine A then its exhaust can
be compressed, or the compression apon exhaust of engine A be slightly relieved so
as to give the exact motion required. In practice only a slight compression of the
exhaust is required.
The exhaust controlling device or plate y passes some distance down into the main
exhaust port so as to turn the current of the exhausts, from the engines and prevent
one from reacting upon the other.
Thus, it will be seen that the regulation and control of the speed of the engine is
very fully accomplished by this regulating device in a most simple and effectual
manner. The regulator valve can, by means of the screw to which it is connected,
be made to close the opening of the exhaust of the secondary engine when this
will be stopped and the main engine will run on alone, and independent of the
secondary engine, should a less capacity be required or should the secondary engine
be out of order.
As already stated, the main valve E is driven by the supplemental piston J,
which, as explained, is divided or recessed, and encloses the main valve between the
parts thereof. And the means for supplying and exhausting steam to and from
supplemental piston J, has already been mentioned as consisting essentially of the
supplemental valve k.
The supplemental valve khas one exhaust cavity and rides upon a seat L from
which lead the steam ports, which may be termed the main steam ports of the
valve chest C and empty into the supplemental piston cylinder at a short distance
from the ends thereof; and ports m, m¹ which may be termed the secondary steam
ports of the valve chest, empty into the supplemental piston cylinder at extreme ends.
thereof. The ports perimit the escape of the spent steam while ports mm have
no exhaust. The exhaust port n of the supplemental valve chest connects with
exhaust port e of engine A, and the steam ports communicate with the exhaust m
at different ends of the stroke of the supplemental piston J through the cavity
under the valve k. The steam ports 1, land m, m' act in the valve chest in the
same manner as the ports a a and b, c c and d d do in the cylinders A and B;
and the supplemental valve J is cushioned on compressed exhausted steam, which is
far preferable to supplying live steam for this purpose, for reasons already given in
connection with the engines.
Provision is made for the steam to enter the valve chest at o between the portions jj
of the supplemental pistons J and also to pass through small ports e to the supple-
mental valve chamber.
The operation of this engine is as follows:-
-
The piston of main engine A being to the left hand end of its steam cylinder, and
its valve movement also at the left, as shown in Fig. 2; and the piston. of engine B
being at the right or opposite, that of engine A and the supplemental valve on its
valve seat in the position shown in Figs. 4 and 8, steam now entering at O and

page_text: passing to the main valve between the sections ; ; of piston J, also passing to supple-
mental valve chamber, will pass through ports m¹, (which are not covered by
valve) to the left hand of valve chest behind the left hand end of piston K while
the exhaust from the right hand end of this piston will pass out of port 1, under
the exhaust cavity in valve K into exhaust port n to exhaust of engine A, and
thence to main exhaust and then out into the atinosphere; the supplemental piston J
carrying the main valve with it and thus opening the main ports to both cylinders of
the engine.
These ports being open, steam passes through port to left of piston in
engine A and through port a¹ to the right of piston in engine B, and both engines
move in opposite directions; the exhaust of engine A escaping out of port a under
the cavity provided into exhaust port e, to main exhaust; while engine B exhausts
through port 1, cavity provided under valve, exhaust port el, main exhaust to
atmosphere.
Engine A in completing its stroke has moved the supplemental valve k in the
opposite direction to that shown in Figs. 4 and 8, and steam is now supplied to and
exhausted from both engines (to A through port a and B through port 6¹), and the
motion of both engines becomes continuous.
While the engines are running, steam is exhausting from them into the main
exhaust, and by turning the hand wheel and with it the screw i which engages the
regulating device g, the exhaust from either engine may be retarded so as to give one
engine the lead of the other, and cause one set of pump valves to seat in advance of
the other, and all noise and concussion will be avoided, and a steady pressure will be
maintained on pumps driven by the engine.
And this steadiness in pressure, absence of noise and jar are also due in part, to the
very effective cushioning of both of the engine pistons, and supplemental pistons upon
compressed exhausted steam or air, in the manner as already described.
This engine is peculiarly adapted to drive pumps of fire engines or stationary
force pumps, as it has only "one valve moving device," and can be run at a very
high rate of speed and by the perfect control of the exhaust, my double cylinder
direct acting steam engine will maintain very nearly a steady pressure on the hose
and prevent all pulsation and throbbing in the hose, which is very desirable. The
engine is also peculiarly adapted for running hydraulic elevators or any other use
where steady pressure, great speed and silent motion is required.
I do not desire to be understood as limiting myself to the particular parts and
detail, as such may be varied and modified within wide limits without departing from
the spirit of sacrificing the advantages and capacities of my invention.
The main valve can have both ends either D or B variety or one end of each type,
both ends being the same type, will cause the engines to run in unity, and then by
the use of the exhaust regulator one engine can be made to finish its stroke in advance
of the other to avoid concussion.
Various other modifications will suggest themselves to a practical steam engineer,
such as different type of valve movement etc. etc. etc.
The strokes of the piston of the main engine are measured by the movement of the
supplemental valve of this engine, and will make its full strokes as this main piston
cannot reverse until the main engine has moved the supplemental valve into position
to supply the steam to reverse the main valve. And as by the use of the regulator
valve in the main exhaust, the main piston of the secondary engine will arrive
at the end of its strokes first, it follows that at whatever speed the engines are
running they will both be compelled to make full strokes which is not the case in the
ordinary double cylinder direct acting engine.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is -
1. The combination of a main direct acting supplemental valved engine as A, with
a secondary engine as B, said secondary engine having no independent supplemental

page_text: valve or valve moving device, and a main valve to supply and exhaust the steam
simultaneously to and from both engine cylinders so that the main engine shall
control the steam admitted and exhausted, to drive the main pistons in their cylinders,
said main pistons being separate and having no mechanical connection with each other
so that one can run in advance of the other, as set forth.
2. A supplemental valved engine cylinder combined with its secondary engine
cylinder having but a main valve, to supply and exhaust the steam to and from both
engine cylinders and a regulating valve in the main exhaust so that the main
supplemental valved engine shall impart the motion to, and the regulating valve control
the motion of, both main pistons in their engine cylinders, as set forth.
3. The combination in a double cylinder direct acting engine, of a regulating valve
in the main exhaust to close the opening of the exhaust of the secondary engine
whereby said secondary engine is stopped, and the main engine permitted to run alone
and independently of the secondary engine, as set forth.
4. In à double cylinder steam engine a regulating device in the exhaust passage
common to both engines, consisting of an adjustable plate or valve to control the motion
of either engine, as set forth.
5. In a double cylinder steam engine, a regulating device in the exhaust passage
common to both engines, consisting of a plate or valve having an elongated end to
separate the exhaust of the two engines, as set forth.
6. In a double cylinder steam engine, the combination with the separate exhaust
passage, of a screw rod operated from the outside, and a regulating device placed
in the main exhaust between the mouths of the separate exhaust ports, said device
consisting of a plate or valve having a threaded opening and being suspended upon
the threaded portion of the rod, as set forth.
7. In a double cylinder direct acting steam engine, employing but one main valve
for both engines, and one engine having an indepedent valve moving device, the
combination with said cylinders and main valve of the supplemental ports and the
main ports; said main valve controlling all of the ports, steam being supplied from
both the main and supplemental ports, to both ends of both main steam cylinders, and
released through the main ports only to arrest and cushion both main pistons at the
termination of the strokes, as set forth.
8. In a double cylinder direct acting steam engine, the combination with a main
valve having a B exhaust cavity at one end, and a D exhaust cavity at the other, and
transverse narrow cavities between them, and side cuts, of the main steam ports a, b
having exhaust ports e between them, and the main steam ports a¹ and b¹ having
exhaust ports el between them, and the secondary steam ports c c, d d opening into
the main valve seat longitudinally between the end set of ports, as set forth.
9. The combination in a double cylinder direct acting steam engine having a main
steam moved valve to supply and exhaust the steam simultaneously to and from both
engine cylinders of a regulating valve in the main exhaust to compel both main pistons
to make and measure their full strokes said pistons having no mechanical connection.
with and moving independent of each other, as set forth.
Dated the 14th day of May 1889.
PHILIP M. JUSTICE,
Associate Agent.