IMPROVEMENTS IN AND RELATING TO STEAM ENGINES
Year: 1883

page_text: LETTERS PATENT to William Phillips Thompson of the Liverpool &. London
Agency for Foreign Patent Solicitors 6 Lord Street Liverpool in the-county
of Lancaster Civil Engineer for an Invention of "IMPROVEMENTS IN AND
RELATING TO STEAM ENGINES a communication from Franklin D. Cumnver
a person resident at Detroit in the County of Wayne and State of Michigan
United States of America
"
COMPLETE SPECIFICATION filed by the said William Phillips Thompson at
the Office of the Commissioners of Patents on the 17th November 1883.
WILLIAM PHILLIPS THOMPSON of the Liverpool and London Agency for Foreign
Patent Solicitors 6 Lord Street Liverpool in the county of Lancaster Civil
Engineer " IMPROVEMENTS IN AND RELATING TO STEAM-ENGINES
nication from Franklin D. Cumnver a person resident at Detroit in the county of
Wayne and State of Michigan, United States of America
"
a commu-
This invention has for its object, firstly, such an arrangement of the steam and
exhaust valves that the latter shall be on a level lower than the cylinder thereby
draining the cylinder; secondly, an arrangement of the main steam and exhaust
valves, whereby all may be operated simultaneously by one eccentric, eccentric rod
and rocker arm, and whereby all the valve motion and all the valves are located
upon one side of the engine; thirdly, to combine with the main exhaust-valve
secondary valves which distribute the exhaust steam to the auxiliary heater and a
condenser, the proportions of the said distributing valves, and their ports to their
seat-ports, and their adjustments as to times of opening and closing in relation to
each other and the main exhaust valves, being such or being capable of such
adjustment that the steam after passing the main exhaust valves, is distributed to
the auxiliary heater and to the condenser in such a way that the feed-water is
heated to a temperature corresponding very nearly with the terminal temperature
of the steam in the cylinder at the time of release, and without causing any
increase of back pressure or variation in the exhaust line upon an indicator diagram
taken from the engine; fourthly, the connection of the cut-off valve with an
... 077

page_text: eccentric and rod independent of those which operate the steam, exhaust, and
distributing valves, for reasons which will be hereinafter explained; fifthly, in
other and minor features of construction.
In the drawings, Fig. 1 is a side elevation of an engine cylinder with the face
plate removed from one end, so as to expose the main steam-valve, exhaust-valve,
and valve leading to the auxiliary heater and condenser.
Fig. 2 is a cross section by a vertical plane passed at right angles to the axis of
the cylinder and through the main steam and exhaust valve chambers.
Fig. 3 is a central section by a horizontal plane.
Fig. 4. is a cross section by a vertical plane passed at right angles to the axis of
the cylinder at its middle point.
Fig. 5.-is a section by a horizontal plane, illustrating the main steam valve at
the left, and with a portion broken away at the right, so as to illustrate in plan
view the main exhaust valve seat beneath.
Fig. 6 is a central cross section by a vertical plane passed through the steam and
exhaust prssages, showing the positions of the valve rods, and also with a jacket
surrounding the cylinder.
Fig. 7-is a side elevation, with parts broken away, illustrating the devices as
applied to an ordinary engine, with the auxiliary heater valve and condenser valve
removed.
Fig. 8-is an elevation on one side. Fig. 9-is a plan view of the engine.
Fig. 10-shows the arrangement of engine, auxiliary heater, and condenser
et cetera.
Fig. 11-is a view of a steam cylinder, viewed from the steam chest side, with
one chest cover removed..
Fig. 12-is an enlarged view of a portion of a similar cylinder, viewed from
above it and having a portion of the top of the cylinder and the steam chest valve-
seat and valves removed.
Fig. 13 is a top view of a cylinder complete of a similar construction.
Fig. 14 is a detail view, partly in section showing the adjustable dogs which
operate the cut-off,
Fig. 15 is a detail side view, illustrating the connection of the main eccentric
rod, the rods of the main steam valves, the exhaust and auxiliary valves, and the
rocker arm.
In the designing and construction of this engine the desire has been to have the
engine very simple and durable, to have all its parts easy of access, and that in the
extreme degree it should be economical, not only at the starting, but that its valves
should be of such design and proportion and the valve seats so arranged that the
valves should remain tight on their seats and move with but little friction, and
that the clearance should be reduced to the least degree possible.
In selecting a valve motion the desire was to adopt the most familiar devices,
that the engine might be suitable for general use, and such as would. enable to be
given to the valves such travel and proportion that great range of adjustment of
the valves in relation to each other might be obtained, and that the steam might be
admitted to the cylinder, exhausted from it and used and distributed in the most
economical manner, and at the same time be used to give the engine different
degrees of lead and compression corresponding to the duty required of the engine,
so that if working with heavy or light loads, with many or few revolutions, or
condensing or non-condensing, it might be possible to give the exhaust valve an
earlier or later closure without causing back pressure or defective release.
To still further carry out the idea of economy and retain still the simplicity of
the engine, a portion of the exhaust-steam from a condensing engine is utilized
while it is possessed of the temperature corresponding to its terminal pressure at
the time of its release from the cylinder, in order to heat the feed-water to a
corresponding temperature. This is accomplished without adding any operating
mechanism whatever to the engine, or increasing the clearance or waste room in.
the cylinder, and without causing any back pressure in the cylinder to the piston,

page_text: or adding any effecting friction or load to any of the operating parts of the engine.
To this end there are used two main steam admission valves B and two main
exhaust valves C, all located in proper relation on the same side of the cylinder H
in the steam chest H¹. These four valves are operated by one fixed eccentric b on
a shaft G receiving motion through suitable transmitting devices from the shaft u
of the fly-wheel W. A rod B connects the eccentric b with the upper end of a
rocker arm D, which has also connected to its upper end the rod & which operates
the main steam valves, while to its lower end is connected the rod d' which
operates the main exhaust and the auxiliary valves. The two main steam valves
are connected by a rod 65, leading through the branch steam-pipe I', and shown in
section in Figs. 4 and 6. The steam valves are arranged to work against a vertical
seat b¹ in which are one or more ports b for the admission of steam to the cylinder.
This seat at the upper end 63 and by its two edges b' is cast to the cylinder; but
the lower end of this seat is not attached to the cylinder. By this arrangement
one is enabled to construct seat of uniform thickness, which is practically
suspended and free to retain a uniformly true plane.
The cylinder is provided with a chest at each end, as shown in the drawings.
The two chests are connected by a horizontal branch steam-pipe I' into which
leads the main steam-pipe I. The lower end of this chest furnishes a shelf h to
carry the main steam and cut-off valves and also to divide the steam chests from
the exhaust chests H³, which are placed horizontally below the steam chests, with
the exhaust-seats below the bottom of the cylinder, so as to drain the cylinder,
and arranged to carry the exhaust-valves in a horizontal position and at right
angles to the steam valves. Both the steam or admission ports and the exhaust
ports at each end of the cylinder are arranged to be in communication with the
same opening or passage into the cylinder. Thus, with the use of separate steam
and exhaust valves only two ports 6 through the cylinder for the admission of the
steam and exhausting it are necessary instead of four, as is usual with engines
employing four or more valves. By this arrangement the exhaust valve seats may
be so designed that they shall be of uniform thickness, and so located as not to be
warped from an even plane by any uneven expansion as the temperature of the
steam and seat varies.
By reference to the drawings, the exhaust side pipe K is scon to be disconnected
from the cylinder, so that the exhaust steam passes directly from the cylinder into
the side pipe and is restrained from all contact with the cylinder, and frees the
cylinder from the distorting effect and uneven expansion that would follow from
having a greater temperature at one side than at the other, and from the evil
effect of incasing the cylinder with saturated steam. The rod or stem d' which
operates the exhaust valves, passes through this exhaust pipe.
s
On the back of each steam-valve is placed a cut-off valve T which may be
operated by a fixed or varying eccentric T' and which is sleeved on the main
eccentric shaft. The point in the stroke of the engine at which the cut-off would
take place and expansion begin may be varied by a rotary adjustment of the
cut off eccentric T¹ forward or in a reverse direction automatically, as is done by
the governor, which forms the subject of another application for a patent, or in the
ordinary way.
The rod T connects the eccentric T¹ with the rod d, which
operates directly the cut-offs which are connected by a rod d' passing through the
branch steam-pipe I', and shown in section in Figs. 4 and 6.
It will be seen that there are employed slide-valves, plain flat plates, gridiron-
valves, preferably. When the ordinary D-valve is used with automatic engines
and high pressures the area under the valve is necessarily very great-about six
times greater than would be necessary for admission only-and by the use of
gridiron-valves and separate valves for admission and exhaust arranged with them
four or more ports, the necessary travel is reduced three, four, or more times, so
that by the reduction of travel and port area under the steam valves the friction
is very much lessened, and also distributed, so that steam at very high pressure
may be used with these engines, and the economy of the greater expansion and the

page_text: use of drier steam may be obtained. Further this system of operating the valves
gives to them a uniform travel, and all parts of the seat wear alike, and from this,
as well as the tendency of the seats to remain in an undisturbed plane, the valves
are liable to remain tight on their seats. With most automatic engines the
admission-valves have a varying travel, and as the valves and seats have not an
even friction over their entire surface, the valves and seats are worn unevenly, and
leak from this cause.
As the main and exhaust valves are operated by a fixed eccentric, and the cut-
off valves by a separate eccentric, one is enabled to give to the main steam and
exhaust valves such a travel in relation to the width of the main admission and
main exhaust ports that by spreading the main valves or adjusting them so as to
be at greater or less distances from each other, the steam valves may be given
greater or less lap, as desired, and, of course as the lap of the main valve is
increased, and after there has been given to the exhaust valves necessary lead, that
steam may be exhausted freely and without back pressure, one is enabled to
increase the compression and cause an earlier closure of the exhaust valves in
proportion as the lap of the main valves is increased, without decreasing the
exhaust lead or causing back-pressure. In short, there may always be given
to this engine any desired compression without compromising the exhaust lead or
compromising the benefit resulting from the desired compression by giving back-
pressure to the piston. In this engine all the valves are arranged on the stems so
each valve may be adjusted independently of any other.
By referring to Figs. 8 and 9 it will be seen that the main eccentric is placed in
front of the girder, and by its rod is attached or connected to a double roeker-
arm D, at the upper end of the upper arm, and to the same end of the upper
rocker-arm, and to the opposite end of said arm is attached the stem that operates
the two main steam-valves. At the lower end of the lower arm of the rock-shaft
is attached the rod that operates the main exhaust-valves. This arrangement of
the chest and valves as fully described, allows of this very simple arrangement for
operating the mechanism, which consists of only one eccentric, one eccentric rod,
one rocker-shaft, with its two arms, and two valve-stems.
The cut-off valves are operated by the cut-off eccentric, one eccentric rod, and
one valve stem, and the arrangement is such that all the rods are straight.
So far this Specification describes a non-condensing engine. The condensing
engine is arranged with auxiliary valves E and F, which are attached to the
exhaust stem which operates the main exhaust-valve, and in this way they are
operated without adding any mechanism to the engine; and the arrangement of
the steam-valves and the relation between the travel of the valves and widths of
the ports, as described, allows by giving motion to the auxiliary or distributing
valves from the same eccentric that drives the main steam and exhaust valves, of
the regulating of their opening and closing at such times that steam is distributed
by said auxiliary valves to the auxiliary heater and condenser in such proportions
to the whole volume of steam that there is given to the feed water, with a portion
of the exhaust steam, while retaining its terminal pressure, a temperature
corresponding very nearly to the temperature of the steam in the cylinder at the
time of its release. It is accomplished in the following manner,
It will be observed that when the main exhaust-valve is closed the auxiliary
heater valve and condenser-valve are both closed; but when the exhaust valve
begins to open the auxiliary heater valve opens simultaneously, so as to give
momentarily a free exit for the steam into the heater. Now as the pressure
accumulates in the heater, and just at the moment it would otherwise operate to
create a back-pressure through the exhaust-valve into the cylinder the further
movement of the valve stem causes the heater valve to close, and before it fully
closes the condenser valve begins to open. The latter however having small but
numerous ports, opens so fully and so quickly that the freedom of the exhaust is
not impaired. Another effect relative to the valves is important. There is no
pressure of the heater valve upon its seat, for as soon as the steam begins to

page_text: exhaust it finds its valve open, and as soon as it closes the condenser valve has
opened and the back-pressure from within the heater lifts the heater valve from
the seat. Moreover so long as the exhaust is free through the heater valve into
the heater there is no pressure upon the exhaust valve, and only a pressure upon
the condenser valve upon its seat, due to the vacuum beneath and the exhaust
pressure. As soon as pressure would otherwise occur, by the closing of the heater.
valve the condenser valve has opened already. The result of this arrangement of
the valves is that the auxiliary heater valve and condenser valve offer no increased
resistance to the eccentric and its rod beyond what would be created by the
exhaust valve if the said auxiliary heater and condenser valves were not employed.
Another result follows from the foregoing construction: The cylinder having but
two ports, the range of movement of the valve is substantially the same upon
engines which differ very much in size and power and the heater and condenser
valves offering practically no resistance therefore with different sizes of engines
there may be employed a common size of eccentric and eccentric rod.
By
connecting the main steam and exhaust valves and the auxiliary heater and
condenser valves all with the same eccentric rod and the cut-off with the
independent eccentric, the travel of the heater and condenser valves may be
adjusted with respect to each other and to the exhaust valve, so as to distribute
properly the exhaust steam and not effect injurious back-pressure in the cylinder,
which adjustment it would be difficult to effect except by making the cut-off
independent.
As ascertained by Mr F. D. Cummer [sic] and corroborated by other competent
engineers, for the best economy the terminal pressure of steam in the cylinder of
a steam engine should not be less than atmosphere, but should range from two to
five pounds, at least above atmosphere. The corresponding temperature of the
exhaust steam would range at and between these pressures at from 221 degrees to
228 degrees, and higher of course, as the terminal pressure might be greater, so
that with a condensing engine in good proportion to its work with this arrange-
ment, in connection with the other parts of the improved engine, there may be
obtained all the benefit obtainable from high steam up to two hundred pounds
pressure or possibly higher, and the expansion a free exhaust and a compression to
any desired degree under all conditions, with all the benefits resulting from the use
of a condenser. Hot feed-water is also procured for the boiler at a temperature
equal to or greater than could be obtained with an ordinary non-condensing engine,
for if the terminal pressure were enough more to warrant it, the auxiliary heater
would then be closed to the atmosphere by a safety valve and so adjusted that it
would prevent all escape of steam, or allow any portion to escape that might be
desired. If no steam were allowed to escape, of course a drainage pipe would be
necessary to carry off the water that would otherwise accumulate and finally fill
the steam chamber of the auxiliary heater. The effect of this auxiliary device and
its combination with an auxiliary heater have been tried by M³ Cummer [sic] with one
of his eighteen-by-thirty-six engines, and he has verified the results as described
by actual test. This engine is also now in daily operation. When desired a nicely
balanced check-valve may be placed in the pipe connecting the auxiliary heater
with the engine-cylinder, to prevent the lifting of the heater distributing-valve E
by pressure under it after it has closed and the condenser distributing-valve opens.
The only objection to this device is the slight noise made by the closing of the
valve, and which it is preferable to avoid, and, instead use the wedge C³, placed
between the lower ends of the driving-dogs C', that drive the main exhaust-valves
and the top of the heater distributing valves. These driving dogs are provided with
flanges that wear against the under side of the main exhaust-valve seats and
resist the raising of the heater auxiliary or distributing valves when the pressure
underneath them is greater than it is above them. Both valves are open to
examination by removing the face-plate D¹.
E is the secondary valve, governing the admission of steam through it to the
auxiliary heater, and F. the other valve governing the passage leading to the

page_text: condenser. The lap and lead of these respective valves is such that when steam is
exhausted from the cylinder through the exhaust-valve C it finds the condenser.
valve F closed entirely or partially, as may be found necessary, and the heater
valve E open. In case it is desired to employ this engine as an ordinary non-
condensing engine, it is effected by simply removing the two valves last named
and employing the foundation bed, as shown in Fig. 7. It will be understood that
this engine has similar valves at each end of its cylinder, and that the face-plates
are removed, so as to expose only one set in the drawings. In this construction
the arrangement is such that each of the various valves is directly adjacent to the
same face of the engine, so that by removing the face plate or plates each valve
can be attended to from the same position and without in any way disturbing the
other valves. This element of convenience in the arrangement of the valves is
of great importance in caring for an engine. It has also been found that by this
employment of valves E and F with a condensing engine the feed water can be
heated to as high or a higher degree than is usual with non-condensing engines.
In operating engines having their expansion valves riding on the back of the
main or admission valves, it often occurs that the engine, when shut down, stops
at such a point in the stroke, and the main and cut-off valves are in such positions
in relation to each other, that should the main valves be worked by hand by
means of a starting bar the cut-off valve or valves would cover the ports on the
back of the main valves at a time when the main valve would cover the ports
leading into the cylinder. To overcome this difficulty it has been usual to pry the
engine with levers in the desired direction until steam in sufficient volume would
be admitted to start the engine or to unhook both the main and cut-off valves
from the operating rods and work both the main and cut-off valves by hand, or
fix the cut-off valves in a suitable stationary position while the main valves are
being worked by hand.
In order that an engine having the expansion valve or valves may be reversed
or handled at any point in the stroke, the device shown in Figs. 11, 12 and 13 is
provided, in which R is the valve seat, r, the three admission steam ports. S is an
auxiliary port, which is covered and uncovered by a lip S¹ on the valve R¹
simultaneously with the covering and uncovering of the ports r. T is the cut-off
valve. U represents a cock for opening and closing the auxiliary ports S, and U¹ a
handle for facilitating the operation.
It will be seen that the port S cannot be closed by the cut-off valve, but may
be opened and closed at will by the engineer through the medium of the handle U³,
which governs simultaneously a similar valve at each end of the cylinder. In
this way the engineer can at any time operate these valves and give steam to the
cylinder no matter what position may be had by the steam or cut off valves,
so that he can start the engine at will by hand, and without unhooking the
cut-off valve stem or detaching or disturbing the connections of any of the parts.
The peculiar construction of the valve seat, hereinbefore referred to as having
the purpose of preventing warping and leakage of steam at the valve seat, is
intended to form the subject of a separate application for patent.
Having now described the invention as communicated to me, I wish it to be
understood that what I desire to protect under the Letters Patent is :-
1. In a condensing engine, a secondary valve governing the admission of exhaust
steam to the auxiliary heater, and another valve governing the admission to the
condenser, and provided with a relative lap and lead, substantially as and for the
purposes described.
2. In a condensing engine the combination of a steam-valve, exhaust-valve,
heater-valve, and condenser-valve, all arranged adjacent to the same face of the
engine, and directly accessible by removing said face, and without disturbing the
other valves, substantially as described.
3. In an engine, a steam-valve with a vertical seat, and a main exhaust-valve
located beneath the latter, with a horizontal seat, the two communicating with the
cylinder by a single port or opening, substantially as described.

page_text: 4. In a condensing engine, the main steam and exhaust, auxiliary heater and
condenser-valves, connected with and operated by one eccentric and its rod, and,
in combination therewith, cut off valves connected with and operated by an
independent eccentric and its rod, substantially as described.
5. In a non-condensing engine, an eccentric, eccentric-rod, and rocker arm, and
in combination with said rocker-arm, a rod connected with its upper end, to which
the main steam valves are attached, and another rod connected with its lower end,
to which the exhaust valves are attached, substantially as described.
6. The combination with a sliding valve and its rod, of two independent driving
dogs which are attached to the rod and enter a cavity in the valve, the combination
being such that lost motion at the points where the dogs enter the valve may be
compensated by loosening their connections with the rod and forcing the dogs
apart from each other, substantially as described.
7. In a non-condensing engine, a steam valve with a vertical valve-seat, and an
exhaust valve beneath it, with a horizontal seat, the two valves connected with
the opposite ends of a rocker-arm, which is moved by an eccentric and its rod, and
in connection therewith, a cut-off valve connected with and operated by an
independent eccentric and its rod, substantially as described.
8. A steam engine provided with similar steam, exhaust, and cut-off valves at
each end of its cylinder, said valves and their operating rods all located upon the
same side of the cylinder and rendered accessible by removing vertical face-plates,
substantially as described.
9. The combination with the main steam valves and cut-off valves of a cut-off
engine, of independent hand-valves for admitting steam to the cylinder at either
end and exhausting from the other end, whereby the engine may be started when
it has stopped at a point where the ports of the main steam valves are closed by
the cut-offs, essentially as set forth.
In witness whereof I the said William Phillips Thompson havo hereunto set
my hand and seal this sixteenth day of November in the year of our Lord one
thousand eight hundred and eighty three.
TIZM D
HOMPSON
TMD THOMPSON (L.S.)