IMPROVEMENTS IN STEAM ENGINES AND WATER ENGINES
Year: 1877

page_text: LETTERS PATENT to Thomas Charles Watts, of Leadenhall Street, in the City
of London, Engineer, for the Invention of "IMPROVEMENTS IN STEAM ENGINES
AND WATER ENGINES."
Sealed the 3rd May 1878, and dated the 8th November 1877.
"
PROVISIONAL SPECIFICATION left by the said Thomas Charles Watts at
the Office of the Commissioners of Patents on the 8th November 1877.
THOMAS CHARLES WATTS, of Leadenhall Street, in the City of London, Engineer.
IMPROVEMENTS IN STEAM ENGINES AND WATER ENGINES."
My Invention relates to engines of that class in which two or more single-acting
cylinders, fitted with trunk pistons, are arranged in combination with a crank shaft,
to which the said pistons are connected by suitable rods.
In the ordinary construction of steam engines of this class they have very long
steam passages, and as these engines usually run at a very high velocity, the length
of the said passages causes a great. waste or useless expenditure of steam, and a
consequent loss of useful effect in their working.
But, according to my Invention, I avoid this loss or waste of steam, and also the
usual loss of effect by the friction of the stuffing boxes, as will be seen by the
following description.
I prefer to construct my improved engines with two single-acting inverted cylin-
ders placed above a crank shaft. The said cylinders are fitted with trunk pistons,
to each of which is jointed one end of a connecting rod, whose other end is fitted
upon one of the cranks of the said shaft. These cylinders are single-acting, that is
to say, they are moved in one direction only by the steam pressure. Their lower
ends, or the ends nearest the cranks, are open, and the other ends of the said cylinders
are closed.
I prefer to cast the ends or covers in one piece with the body of the cylinder, to
avoid the fitting of separate ends or covers on the same.

page_text: To avoid the necessity for the ordinary long steam passages, and the consequent
loss of steam and useful effect, I have devised a novel arrangement of the valves of
these engines, that is to say, I form the admission ports through the said ends or
covers, and fit a valve upon the same within a suitable casing secured upon the
cylinder ends.
I prefer to employ one valve for each pair of cylinders, and I use a simple-faced
valve fitted on its seat and operated to control the admission and exhaust of the
steam by alternately uncovering and covering the ports in the usual manner.
I prefer, in some instances, to use a circular valve operated by means of a vertical
rod or spindle arranged between the two cylinders, and connected by bevel gearing
with the crank shaft, from which it receives rotary motion.
But, if desired, instead of a circular valve I may use a slide valve of the usual
form, and move it to and fro over the said port face by small rods and cranks
operated by an excentric or cam on the said crank shaft, or by other suitable means.
And, in some instances, the cam or excentric and rods for operating the valve may
be at one end of the crank shaft instead of being in the centre of the engine.
I prefer to exhaust the steam in the usual manner, that is to say, to discharge it
directly through a suitable exhaust pipe instead of into a casing or hollow base, as
in some engines of the class above described, for the reason that when the exhaust
takes place in this last-named manner the leakage or loss of any steam through
defects in the pistons cannot be easily detected, and stuffing boxes and steam joints
have to be provided.
When my Invention is to be applied to a yacht, launch, or other steam vessel, I
prefer to couple two of the above-described engines together instead of constructing
an engine with three or more cylinders.
The said improved engines may be made compound, that is to say, they may
have a small and a large cylinder for the use of high-pressure and expanded steam;
and, if desired, the spaces between the said cylinders may be utilized as a
receiver.
When the said Invention is to be used as a water engine, it will only be necessary
to modify the same by substituting for the above-described valve any of the well-
known or suitable water engine valves.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Charles Watts in the Great Seal Patent Office on the 8th
May 1878.
THOMAS CHARLES WATTS, of Leadenhall Street, in the City of London, Engineer.
"IMPROVEMENTS IN STEAM ENGINES AND WATER ENGINES.'
My Invention relates to engines of that class in which two or more single-acting
cylinders, fitted with suitable pistons, are arranged in combination with a crank
shaft, to which the said pistons are connected by suitable rods.
In the ordinary construction of steam engines of this class they have very long
steam passages, and as these engines usually run at a very high velocity, the length
of the said passages causes a great waste or useless expenditure of steam, and a con-
sequent loss of useful effect in their working.
But, according to my Invention, I avoid this loss or waste of steam, and also the
usual loss of effect by the friction of the stuffing boxes, as will be seen by the
following description and by the aid of the Drawings, which I will now proceed to
describe.
.
Figure 1 is a plan or top view of an engine for ordinary use as a stationary
engine, constructed according to my Invention; Figure 2 is a front elevation of the
same.
Figure 3 is a vertical longitudinal section on the line x, x, Figure 1.
Figure 4 is a vertical transverse section on the line y, y, Figure 1.
Figure 5 is a horizontal section on the line 2, 2, Figure 2.
Figure 6 is a plan or top view of the cylinders and port face of the said engine.
Figure 7 is a vertical longitudinal section illustrating a modification of parts of
the said engine.
Figure 8 is a similar section of a four-cylinder compound or high and low pressure
engine, embodying this Invention.
Figure 9 is a longitudinal section showing modifications of this engine.
Like letters indicate the same parts throughout the Drawings.
For ordinary purposes I prefer to construct my improved engines with a strong
framing A of cast iron or other suitable material, and with two inverted cylinders a
placed above a crank shaft b, as clearly shewn in Figures 3 and 4 of the Drawings.
This crank shaft is supported in suitable bearings b' at or near its ends, these
bearings being attached to the frame A in any suitable manner, and I prefer that
the said shaft should have a central bearing, as shewn at 62. The said cylinders are
fitted with trunk pistons c, to each of which is jointed one end of a connecting
rod d, whose other end is fitted upon one of the cranks bs of the said shaft b.
For small or light engines I prefer to make these connecting rods of phosphor
bronze, and shaped in transverse section, but for large engines I prefer to have
the connecting rods made of steel tubes, with heads or ends of phosphor bronze.
The pistons of these cylinders a are single-acting, that is to say, they are moved in
one direction only by the steam pressure. The lower ends of the said cylinders a, or
the ends nearest the cranks 68, are open, and the other ends of the said cylinders are
closed, as shewn at a¹.
I prefer to cast the ends or covers a¹ solidly, or in one piece with the body of the
cylinder, to avoid the work of fitting separate ends or covers on the same.
>
To avoid the necessity for the ordinary long steam passages, and the consequent
loss of steam and of the useful effect of steam engines of this class, I have devised a
novel arrangement of the valves and ports and mechanism for operating the valves
in these engines; that is to say, I form the admission ports e through the said ends
or covers a¹, and fit a valve f upon the same within a suitable casing g secured upon
each of the said cylinder ends a'.
I prefer to employ one valve for each pair of cylinders, as shewn, and I use a
faced valve fitted on its seat h, and operated to control the admission and exhaust

page_text: of the steam by alternately uncovering and covering the admission ports e and
exhaust port e* in the usual manner.
When a circular rotating valve is used, as in the engine illustrated in Figures 1
to 6, it is operated by means of a vertical rod, shaft, or spindle i, arranged between
the two cylinders a, and connected by bevel gear wheels j, k, with the crank shaft b,
from which it receives rotary motion. To reduce the friction of this valve on its
face, I provide the rod or spindle i with an adjustable collar i, which works on the
top of the bearing or bush 2 of the spindle i, and I make the upper end of the said
spindle square, and fit the same in a square hole in the valve; or I otherwise form
the said spindle, and fit it in the valve in such a manner that it will act to turn the
said valve while allowing it free movement on the spindle, so that the valve may
bear properly on its face independently of the weight of the said spindle and its
gearing. Furthermore, I form a flange fl around the upper part of the said valve
to fit the interior of the casing g, which flange takes off a great portion of the down-
ward pressure of the steam upon the said valve.
The steam enters by the pipe or passage between the top and bottom flanges of
the said valve, which has a port or aperture at ƒ2; and each time this aperture passes
over the port e of either cylinder steam is admitted to the same, while the exhaust
steam passes from the other cylinder through the cavity fs of the valve and the
exhaust port e* to the exhaust pipe n. By thus fitting the valve upon a square
portion of the spindle it will always adjust itself freely to its seat, and the accuracy
of its working will not be affected by the wearing of the spindle or the gearing.
Holes may be drilled in the port face or seat to contain lubricating matter.
•
When this form of valve is used, I prefer to drive the governor by means of gear
wheels from the shaft or spindle i. In Figure 4 I have shewn the governor at o and
the throttle valve at o' adjacent to the valve casing; p is a spur wheel on the
spindle ; and 7 is a pinion on the governor spindle projecting through the frame A
of the engine, and gearing with the wheel pl
,
If desired, instead of a circular valve I may use a slide valve of the usual form,
and move it to and fro over the said port face by small rods and cranks operated by
an excentric or cam on the said crank shaft, or by other suitable means; and in
some instances the cam or excentric and rods for operating the valve may be at one
end of the crank shaft, instead of being in the centre of the engine. This modifi-
cation of my Invention is illustrated in Figure 7. The valve fis in this case moved
to and fro over the steam ports e and exhaust port e* by a cam and lever 8. The
said cam is fixed on the crank shaft b, and has a groove r¹ into which projects the
lower end of the lever 8. The said lever has its fulcrum at s¹, and its upper end
projects into the cavity of the valve and enters and works in a recess 82 in the top
of the same.
It is obvious that the rotation of the said cam will oscillate the lever 8, and thereby
impart, a reciprocating movement to the valve f.
I prefer to exhaust the steam in the usual manner, that is to say, to discharge it
directly through a suitable exhaust pipe, as above described, instead of into a casing
or hollow base, as in some engines of the class to which this Invention relates, for
the reason that when the exhaust takes place in this last-named manner the leakage
or loss of any steam through defects in the pistons cannot be easily detected, and
stuffing boxes and steam joints have to be provided.
In cases where a fly wheel pit would not be objectionable the base can be
shortened, making the engine considerably lighter and more compact than is other-
wise practicable.
I may provide any suitable gear or apparatus for reversing these engines, but an
arrangement I find to answer well in connection with the rotating valves is the
following, that is to say:-I divide the valve stem into two parts connected to a long
sleeve by cotters or pins; the said sleeve has in it spiral grooves, into which the
cotters or pins fit in such manner that when the said sleeve is raised or lowered the
upper part of the stem, and with it the valve, will be shifted or turned half way

page_text: round upon its seat, thereby altering the relation of the valve to the crank in the
required manner.
In the engine where the slide valve and cam are employed any of the well-known
arrangements for adjusting the cam on the crank shaft may be adopted to afford the
means for reversing the engine.
When my Invention is to be applied to a yacht, launch, or other steam vessel, I
prefer to couple two of the above-described engines together instead of constructing
an engine with three or more cylinders.
The said Invention may be applied to compound engines, that is to say, engines
that have a small and a large cylinder, or two or more small and large cylinders
for the use of high and low pressure or expanded steam.
!
In Figure 8 I have shewn the adaptation of the said Invention to a four-cylinder
compound engine. A is the frame on which the cylinders and other parts are
mounted, as in the engine above described; a, a, are the high-pressure cylinders;
and a, a, the low-pressure cylinders. The small or high-pressure cylinders a are
provided with trunk pistons c, whose connecting rods & extend to and are fitted upon
the cranks bs, as above described.
It will be seen that the said small and large cylinders are concentric with each
other, and that the pistons c* of the large cylinders are annular, as in other
compound engines. The said pistons c* are provided at their lower ends with
flanges c', which are fitted to flanges c² on the pistons c, and by means of screws
passed through these flanges; or by other suitable means the said pistons are secured
to each other, so that the two pistons exert their joint action on the crank through
the medium of one connecting rod. This arrangement of the pistons permits the
use of a condenser in an engine with single-acting cylinders.
The valve f, in this engine, may be a rotating valve, as shewn; it is provided with
passages and cavities for the distribution of the steam as follows, that is to say :-The
port or passage f2 supplies the steam to the admission ports e of the high-pressure
cylinders a, and steam is conducted from these cylinders by the passage f³ to the
large or expansion cylinders, and is exhausted from the latter through the passage f6,
whence it passes to the exhaust pipe n. The rotation of this valve is effected by
means of a vertical spindle geared with the crank shaft, and connected with the said
valve as in the engine first above described.
When the said Invention is to be used as a water engine, it will only be necessary
to modify the same by substituting for the above-described valve any of the well-
known or suitable water engine valves.
In Figure 9 I have shewn a modification in the construction of the valve, whereby
I am enabled to greatly reduce the diameter of the same. In this modification the
said valve has a central projecting portion f', which is fitted into the central bored
tubular chamber a7 in such a manner as to turn freely therein. The said valve has
a port or aperture at f2 for supplying steam to the high-pressure cylinders a, and a
passage fo for conducting the steam from the high-pressure cylinders a to the low-
pressure cylinders a*, and the said centrally-projecting portion f' is made hollow
and provided with a passage and aperture fº, f10, whereby the steam passes from the
low-pressure cylinders to the exhaust pipe n.
When my Invention is.applied to small steam engines, I prefer to arrange the
cylinders below the crank shaft to allow space for a comparatively large fly wheel;
and for water engines this arrangement affords the additional advantage of allowing
the water exhausted from the cylinders to pass away more conveniently and quickly
than would otherwise be practicable.
Having thus fully described my said Invention, and the manner of performing
the same, I wish it understood that I claim,-
First. In an engine with single-acting cylinders, that is to say, with cylinders
whose pistons are moved in only one direction by the steam or other fluid, and
which pistons are connected with cranks arranged across the ends or transversely to
the axial line of the said cylinders, the rotating valve operated by a shaft, rod, or
spindle geared with the said crank shaft, and which valve is arranged in combi-

page_text: nation with suitable ports or passages opening directly into the end of the cylinders;
as above set forth.
.
Second: The modification of my Invention, wherein a reciprocating slide valve is
employed, as shewn in Figure 7 of the Drawings, and as above specified:
Third. The modification of my Invention embodied in the compound or high and
low pressure engine; with four cylinders, as shewn in Figure 8 or in Figure 9 of the
Drawings; and in which the pistons of the high and low pressure cylinders are
connected with each other, as above set forth.
In witness whereof, I, the said Thomas Charles Watts, have hereunto set my
hand and seal, this Seventh day of May, in the year of our Lord One
thousand eight hundred and seventy-eight.