Improvements in Compound Steam Engines.
Year: 1894

page_text: Date of Application, 13th Mar., 1894-Accepted, 8th Seot, 1894
COMPLETE SPECIFICATION.
[Communicated from abroad by FREDERIC CANDEE WEIR, of Cincinnati,
Hamilton County, Ohio, United States of America, Manufacturer.]
Improvements in Compound Steam Engines.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45 Southampton Buildings, in the County of Middlesex, 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 :-
The object of my invention is to provide a progressively expansion steam engine;
it is shown of the triple expansion type. I employ a differential piston working in
a differential cylinder, and constructed in the manner hereinafter explained.
The various features of my invention are fully set forth in the description of the
accompanying drawings making a part of this Specification, in which-
Fig. 1 is a longitudinal central section of my improvement.
Fig. 2 is a section on line c, r, Fig. 1.
Fig. 3 is a plan view of the auxiliary valve.
Fig. 4 is a bottom plan view of the main valve.
Figs. 5, 6 and 7 are views similar to Fig. 1, showing different positions of the
valves.
The cylinder is of the differential form. A represents a larger cylinder, B the
smaller cylinder. C represents a reservoir or chamber; it is shown as an annulus
around the cylinder B, its inner periphery forms a bearing for the smaller piston D.
E represents the larger piston; both pistons are united and form a differential
piston. F represents the piston rod, G the cross head. Ha casing enclosing the
engine. I the steam chest. K the auxiliary valve. M a main valve; L the
upper seat of the auxiliary valve; N the lower seat of the auxiliary valve and
the upper seat of the main valve. O represents the pipe for admitting steam into
the steam chest. P represents the exhaust pipe.
I have shown the differential piston constructed of two pieces connected to the
piston rod F, but they may be cast in one piece. The cylinder B supports the
smaller piston D.
a represents a packing at the rear end; the piston E is packed in the usual
manner by rings b. The main valve is provided with the main port 1 by which
steam is admitted through port 2 to the rear face of the piston D, in position shown
in Fig. 1. It is also shown as exhausting steam from the cylinder A through
port 5 to exhaust port 6. Ports 5 and 6 coinmunicate through port 7 of the inain
valve. When the valve moves forward into the position shown in Fig. 5 it cuts off
the admission of steam to port 2, port 8 of the valve connects with port 4, and the
steam is exhausted through port 2 and port 8 of the valve and port 4 of the steam
chest into the annulus C, where it is stored for being compounded when the valve
is moved back again into the normal position shown in Fig. 1; the steam stored in
the annulus C is passed by ports 4, 8 and 3, on to the smaller area of piston E,
acting thereon by expansion in unison with the direct steam admitted by port 2 on
to the rear end of the smaller piston D. When the valve is again moved forward
into position shown in Fig. 5, ports 3 and 5 are connected by port 7 of the valve,
and the steam is exhausted from the smaller area of the piston E through ports 3, 7
and 5, over on to the larger area of piston E, where it is utilized by expansion to
make the return stroke. Thus the steam is used first directly upon the smaller
area of piston D, thence passed in the annular C, thence expanded upon the smaller
area of piston E, and then expanded from the smaller on to the larger area of
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page_text: piston E making a triple expansion. I have shown the main valve adjustable on
its seat so that the engine may be used as a direct acting engine. To do this I
provide an additional port 11 in the main valve and adjust it on the seat as shown
in Fig. 6, instead of being adjusted as shown in Fig. 1. Port 1 of the main
valve supplies live steam by port 5 to the larger area piston. The position of
the valve for making the opposite or return stroke is shown in Fig. 7; in this
position port 1 communicates with port 3, admitting live steam on to the smaller
area of piston E and port 11 admits live steam through port 2 on to the rear end of
piston D. As these two areas are about equal to the area of the large piston E,
the engine is balanced or driven relatively by the same amount of pressure on
either stroke. When the engine is being thus used the port 4 is cut off at all
times so that the annulus C is not brought into use.
I have shown as a means of adjusting this valve the valve stem 12 divided in
two parts and connected by a coupling sleeve 13 which is threaded. right and
left at each end connecting the valve stem sections. 14 represents a hand wheel
for turning a sleeve 14' splined to the sleeve 13 and journalled in bracket 18,
and through which the sleeve 13 is rotated. 15 represents a worm segment
engaging with worm threads on the outer periphery of sleeve 141 operating an
indicator hand 16, so that the operator can see the exact position of the main
valve; and this is the preferred form of adjusting mechanism employed for
converting the engine from the triple expansion into the direct acting engine.
I have likewise shown the valve seats adjustable vertically by means of taper
plates operated by threaded bolts, as shown in elevation in Fig. 2.
L represents the upper valve seat, N the lower valve seat. The ends of these
seat plates are grooved to receive the inclined tongues a* of the sliding plates¨b* ¿*.
represents screw rods the inner ends of which are threaded and engage with
threads tapped in the sliding plates 6*6*. These screw rods project through
stuffing boxes d* d* outside of the steam chest. e represents the heads of the
screw rods c✶ to which a wrench can be applied to turn rods c* which moves the
plates longitudinally in ways f* Fig. 1 provided for them in ends of steam chest.
This movement of the plates raises or lowers the valve seats L, N according to
direction in which the screw rods are turned. When used as a direct engine steam
is exhausted from port 3 through side ports 12¹ in the main valve, as shown in
dotted lines in Fig. 4.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :
1. In a compound engine, the combination of the differential cylinder A, B, with
the differential double acting piston E, D, the reservoir C formed within the shell
of the cylinder and steam chest, and a valve provided with suitable ports and
passages for expanding the steam progressively on succeeding piston faces,
substantially as described.
2. In a compound engine, the combination of the differential cylinder A, B, with
the differential double acting piston E, D, the reservoir C formed within the shell
of the cylinder and steam chest, and a valve provided with suitable ports and
passages for expanding the steam progressively on succeeding piston faces, the last
expansion driving the piston in the opposite direction from the preceding one,
substantially as described.
3. In a compound engine consisting of the differential cylinders A, B, the storage
reservoir C, the steam chest provided with the ports 2, 3, 4, 5 and 6, and the main
valve provided with a main and branch ports and cut offs for opening and closing
the said chest ports for progressively compounding the steam, substantially as
specified.
4. In combination with the progressively expansive steam engine composed of
two cylinders of different areas and pistons of different areas working therein, the
live steam port 2, and storage reservoir C, a port 4 communicating alternately with

page_text: ports 2 and 3, and the port 5 for supplying steam to the larger cylinder, and a
suitable valve for operating said piston by cutting in and out the respective ports
at each alternate stroke of the valve, substantially as specified.
5. In combination with the compound steam cylinders A, B, the ports 2, 3, 4, 5
and 6, and a main valve provided with ports 1,7 and 8, adapted to open and close
the said chest ports, whereby the direct steam is admitted on the smallest piston
and progressively expanded upon the successive faces of the larger pistons,
substantially as specified.
6. In combination with the compound cylinders A, B, and pistons D, E, the
storage reservoir C, the main valve provided with ports 1 and 11, and branch
ports 7, 8 and 12¹, and mechanism for adjusting said valve on its seat and adapted
to communicate with the respective ports of the cylinder whereby the engine
may be used as a direct or compounding engine by the adjustment of said valves,
substantially as specified.
7. In combination with the progressive compound engine, composed of unequal
cylinders and pistons having three communicating supply ports 2, 3 and 5, and main
valve provided with the supply ports 1 and 11, and the branch ports 7 and 8,
substantially as specified.
DL: 19L
March 1901
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.