IMPROVEMENTS IN COMPOUNDING THE CYLINDERS OF STEAM ENGINES SO AS TO WORK ON THE HIGH AND LOW PRESSURE PRINCIPLE
Year: 1876

page_text: LETTERS PATENT to John Sturgeon, of West Derby, near Liverpool, in the
County of Lancaster, Engineer, for the Invention of "IMPROVEMENTS IN
COMPOUNDING THE CYLINDERS OF STEAM ENGINES SO AS TO WORK ON THE
HIGH AND LOW PRESSURE PRINCIPLE."
Sealed the 14th July 1876, and dated the 16th February 1876.
PROVISIONAL SPECIFICATION left by the said John Sturgeon at the Office of
the Commissioners of Patents on the 16th February 1876.
JOHN STURGEON, of West Derby, near Liverpool, in the County of Lancaster,
Engineer. "IMPROVEMENTS IN COMPOUNDING THE CYLINDERS OF STEAM ENGINES
SO AS TO WORK ON THE HIGH AND LOW PRESSURE PRINCIPLE."
This Invention has for its object "Improvements in Compounding the Cylinders
of Steam Engines so as to Work on the High and Low Pressure Principle," and "
consists in the first place in arranging the cylinders in the following manner, that is to
say-Instead of placing one high and one low pressure cylinder end to end or side
by side with independent gear to the crank shaft, and with independent valves and
valve gear as has been the general custom heretofore, I place two high-pressure
cylinders of smaller size one on each side of the low-pressure cylinder, the piston
rods of the three cylinders being connected to one cross head working in guides in
the usual manner. Or conversely the low-pressure may be divided into two, one
on each side of a high-pressure, all being connected in same manner.
The ports
from the two side cylinders communicate by means of passages through the end
covers, or along the sides of the central cylinder with passages leading up to one
main valve face common to all, which is situated at the top of the central cylinder,
thus forming five ports on the valve face, namely, one exhaust port, and two ports
on each side thereof. A slide valve having a port or passage through it passing
over the exhaust opening working over these ports, first admits steam to the high-
pressure cylinders, from whence it passes through the above described port of the
slide valve to the low-pressure cylinder, and from that again through the exhaust
opening of the slide valve to the main exhaust. By these means I make a single valve
to control both high and low-pressure cylinders, and I also save the extra length
required where the cylinders are placed end to end, and the extra connecting rod
and other gear where placed side by side in the ordinary manner.

page_text: It is obvious that the same arrangement may be carried out by placing the two
outer cylinders, whether high or low pressure, above and below the central cylinder,
the valve box being at the side thereof instead of on the top. I also arrange the
high and low pressure cylinders one inside the other and concentric therewith,
either the high inside the low or the low inside the high, the inner cylinder being
truly turned on the outside and the piston of the outer one being of annular form
and working theron, the piston rods being connected in the manner above described
to the cross head; but in this case the passages to the inner cylinder are necessarily
continued through the end covers.
Any convenient number of cylinders may be combined and compounded in this
manner, additional ports being provided in the valve chamber and in the valve to
correspond therewith.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Sturgeon in the Great Seal Patent Office on the 10th August
1876.
JOHN STURGEON, of West Derby, near Liverpool, in the County of Lancaster,
Engineer. "IMPROVEMENTS IN COMPOUNDING THE CYLINDERS OF STEAM ENGINES
SO AS TO WORK ON THE HIGH AND LOW PRESSURE PRINCIPLE."
The
This Invention has for its object improvements in compounding the cylinders of
steam engines so as to work on the high and low pressure principle, and consists in
the first place in arranging the cylinders in the following manner, that is to say:
Instead of placing one high and one low pressure cylinder end to end or side by
side with independent gear to the crank shaft, and with independent valves and
valve gear as has been the general custom heretofore, place two high-pressure
cylinders of smaller size, one on each side of the low-pressure cylinder, the piston
rods of the three cylinders being connected to one cross head working in guides in
the usual manner.
Or conversely the low-pressure may be divided into two, one
on each side of a high-pressure cylinder, all being connected in same manner.
ports from the two side cylinders communicate by means of passages through the
end covers or along the sides of the central cylinder, with passages leading up to
one main valve face, common to all, which is situated at the top of the central
cylinder, thus forming five ports on the valve face, namely, one exhaust port and
two ports on each side thereof. A slide valve having a port or passage through it
passing over the exhaust opening working over these ports, first admits steam to
the high-pressure cylinders, from whence it passes through the above described port
of the slide valve to the low pressure cylinder, and from that again through the
exhaust opening of the slide valve to the main exhaust. By these means I make a
single valve to control both high and low-pressure cylinders, and I. also save the
extra length required where the cylinders are placed end to end, and the extra
connecting rod and other gear where placed side by side in the ordinary manner.
It is obvious that the same arrangement may be carried out by placing the two
outer cylinders, whether high or low pressure above and below the central cylinder,
the valve box being at the side thereof instead of on the top. I also arrange the,
high and low pressure cylinders one inside the other and concentric therewith,
either the high inside the low or the low inside the high, the inner cylinder being
truly turned on the outside and the piston of the outer one being of annular form
and working thereon, the piston rods being connected in the manner above described
to the cross head; but in this case the passages to the inner cylinder are necessarily
continued through the end covers.
Any convenient number of cylinders may be combined and compounded in this.
manner, additional ports being provided in the valve chamber and in the valve to
correspond therewith.
The before-going being the nature, object, and purposes of this my Invention, I

page_text: will now proceed to describe more in detail how the same may be carried into
practical effect, and for that purpose I have hereunto attached a Sheet of Drawings
inarked with letters and figures of reference corresponding with those in the
following explanation, and throughout the various views like letters and figures
denote similar parts.
Figure 1 represents a side elevation shown broken off, and partly in section of a
high and low pressure engine according to my Invention as applied to a steam.
pump; Figure 2 is an end view of Figure 1, shown partly in section through the
line A, B, Figure 1; Figure 3 is a plan of Figure 1.
Figure 4 is a plan illustrative of my Invention as applied to engines generally;
Figure 5 is an end view of Figure 4.
Figure 6 is a section of a cylinder compounded on the annular principle;
Figure 7 is an end view of Figure 6.
Upon reference to Figures 1, 2, and 3, it will be seen that the cylinders of the
steam pump illustrated are compounded so as to work on the high and low pressure.
principle. This is effected by placing_two high-pressure cylinders A, A¹, one on
each side of the low-pressure cylinder B. The piston rods C, D, and E are con-,
nected to one common cross head F working in guides G in the usual way. The
two side cylinders being the high-pressuse cylinders A, A³, communicate by means
of passages H, K, in the end covers with passages or ports b leading up to one main
valve face S common to all three cylinders A, A', and B. There are thus five ports
on the valve face S, namely, one exhaust port a and two ports on each side thereof.
The ports b being the ports for the high-pressure cylinders A, A', and communicating
therewith by the passages H, K, in the end covers thereof, and the ports & being
the ports for the low-pressure cylinder B. There is one slide valve R common to
all three cylinders and arranged with a port or passage of through it, passing over
the exhaust opening a¹. The slide valve R working over the ports a, b, and d, first
admits steam to the high-pressure cylinders A, A', from whence it passes through the
port f of the slide valve R to the low-pressure cylinder B, and from the low-
pressure cylinder B through the exhaust opening of the slide valve to the main
exhaust a. By this arrangement I make the slide valve R control both the high-
pressure cylinders A, A', and the low-pressure cylinder B.
In the example shown at Figures 1, 2, and 3, the slide valve R is worked by the
auxilliary piston T which receives its motion by means of the supplemental slide
valves V, V, controlled by the rod and tappet gear Z.
It will be obvious that the arrangement just described may be carried out by
making the two outer cylinders either high or low pressure, and by placing them
above and below the central cylinder. In such case the valve box being at the side
instead of the top, as shown at Figures 4 and 5.
The annular principle of compounding steam cylinders according to my Invention
will be seen upon reference to Figures 6 and 7, and consists in placing the
cylinders A, A¹, one inside and concentric with the other, and these inside and
concentric with the cylinder B. This arrangement gives two grades of expansion,
namely, the steam is first used in the cylinder A, then in the cylinder A', and
lastly in the cylinder B. The valve face S is provided with seven ports for this
purpose, a being the exhaust; b, the ports of the cylinder A; 6', the ports of the
cylinder A¹; and d being the ports of the cylinder B. The pistons W, X, of the
outer cylinders are of annular form, and the piston Y of the centre cylinder is of
ordinary type. The respective piston rods are connected to a cross head common
to all.
Any convenient number of cylinders may be combined and compounded in this
manner, additional ports f, f¹, being provided in the valve R to correspond there-
with. This arrangement is particularly applicable to engines of the non-rotative
class in which the load is equal throughout the stroke, such as pumping engines,
blowing engines, and other like engines, in which the steam power is applied
direct without intermediate gear, such as cranks, discs, fly wheels, and attendant
parts.

page_text: My Invention enables the steam to, be economised by the reuse of the steam
expansively in such a manner as to maintain a nearly uniform pressure throughout
the stroke.
Having now described the nature of my said Invention and shown a manner in
which the same is or may be used or carried into practical effect, I would observe
that what I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent is,-
Firstly. The general arrangement and construction of three cylinders, such
as A, A¹, and B, arranged to actuate one common cross head, the cylinders A, A¹,
being high-pressure and exhausting into the cylinder B, or the cylinder B being
high-pressure and exhausting into the cylinders A, A¹, as herein-before described
and shown in the accompanying Sheet of Drawings at Figures 1, 2, 3, 4, and 5.
Secondly. The construction of a valve, such as R arranged with a port, or ports
such as ff, in combination with high and low pressure cylinders, such as A, A¹,
and B, as shown in the accompanying Sheet of Drawings at Figures 1, 2, and 6.
Thirdly. The arrangement and construction of three or more cylinders with end
covers common to all, such end covers being arranged with passages, such as H, K,
leading from the ports, such as b, b, d, to the interior of the cylinders, as herein-before
described and shown in the accomanying Sheet of Drawings.
Fourthly. The combination of an internal ported valve, such as R with concentric
cylinders and ports through the end covers, such as shown in Figures 6 and 7 of
the accompanying Drawings, as applied to direct-acting non-rotative engines.
In witness whereof, I, the said John Sturgeon, have hereunto set my hand
and seal, this Eighth day of August, in the year of our Lord One thousand
cight hundred and seventy-six.
JOHN (L.S.) STURGEON.