IMPROVEMENTS IN STEAM ENGINES FOR TEMPORARILY INCREASING THE POWER NORMALLY AND USUALLY EXERTED
Year: 1884

page_text: I, GEORGE WESTINGHOUSE, Junior, of Pittsburgh, in the County of Allegheny,
State of Pennsylvania, and United States of America, engineer, do hereby
declare the nature of my invention for “IMPROVEMENTS IN STEAM ENGINES FOR
TEMPORARILY INCREASING THE POWER NORMALLY AND USUALLY EXERTED 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 enable increase of power above that normally
and usually exerted, to be developed, in the operation of a steam engine, in
accordance with, and as required by, additional resistance encountered in the per-
formance of temporarily increased duty, imposed from time to time upon the engine.
To this end, my improvements consist in a novel method of and means for effecting
an increased supply of steam to one or more pistons of an engine, upon application
of increased duty thereto, and in the combination, with an engine having two or
more pistons, of a governor or regulator, and supply ports and passages, controlled
by said governor and leading from a communication with a main, steam pipe to
the supply sides of said pistons, all as hereinafter more fully set forth.
In. the operation of steam engines of various descriptions, a temporary increase
of power is frequently necessary or desirable, to enable the engine to perform duty
in excess of that within its normal capacity, such duty being comparatively
infrequent, or of such short duration as not to render economical the permanent
employment of an engine of higher power than that which is required to be
developed under ordinary conditions of operation. To render such increase of power
practicable, in an engine having more than one piston, as in a compound reciprocating
engine, or a rotary engine, having a series of pistons, whether simple or compound,
'or in an engine working steam expansively in a single cylinder, I automatically and
coincidently supply two or more pistons of the engine with steam, or open to the
cylinder of an engine, communication with one or more independent steam supply
passages, under and in accordance with the degree of additional duty imposed,
regulating such increased supply by, and terminating it with, such additional
imposition of duty.
•
In the accompanying drawings: Figure 1 is a transverse section through the
cylinders of a two cylinder compound reciprocating engine, illustrating an application
of my invention': Fig. 2, a longitudinal section through the cylinder and steam chest

page_text: -
of an engine adapted to work steam expansively in a single cylinder, illustrating
another application of my invention: Fig. 3, a longitudinal section through one
cylinder of a compound rotary engine, illustrating a further application, and:
Fig. 4, a transverse section, at the line x, x, of Fig. 2.
The
In the practice of my invention, I provide a governor or regulator 1, of any
Buitable construction, and connect the same with a governor valve 2, fitting seats in
a valve chest 3, and controlling the admission of steam from a main supply pipe 4,
to a main steam passage 5, leading to the primary piston of the engine, and an
auxiliary or supplemental steam. passage 6, leading to a secondary piston, that is to
say, one which is subsequent to the primary piston in the reception of steam.
capacity of the main steam passage 5, and the relation of the governor valve thereto,
are such that when said passage is fully opened to the steam pipe 4, by the move-
ment of the governor valve, the maximum quantity of steam required in the normal
operation of the engine shall be supplied to the primary piston thereof, through
the main steam passage 5, and the valve is so set, relatively to the opening of the
supplemental steam passage 6, that said passage shall not be opened to the steam
pipe until after the maximum admission of steam through the passage 5, shall have
been effected. Upon the application of duty greater than that within the capacity
of the engine, under the maximum steam supply afforded to the primary piston
through the passage 5, the continued traverse of the governor valve, effected by the
increased resistance upon the governor, opens the supplemental steam passage 6, to
the steam pipe 4, to a greater or less degree, proportionate to the resistance, and,
by affording a further supply of steam, from the main steam pipe 4, through the
- passage 6, to the primary piston, or to another or secondary piston of the engine,
correspondingly increases its power during the continuance of the duty imposed,
upon the cessation of which the governor closes the supplemental passage 6, and
continues its regulation for the normal operation of the engine, by controlling the
main passage to the primary piston, in the usual manner.
My invention is illustrated in Fig. 1, as applied in connection with a two
cylinder compound reciprocating engine, the main steam passage 5, supplying steam
to the steam chest 7, and thereby to the primary piston, that is to say, the piston
of the high pressure cylinder 8, and the supplemental steam passage 6, supplying,
under increased duty of the engine, steam to the steam chest 9, and piston of the
low pressure cylinder 10, said piston, which in the construction is a secondary
piston, thereby receiving steam directly from the boiler, in addition to its normal
supply, to wit, the exhaust steam of the high pressure cylinder 8. It will be
obvious that in an engine having more than one low pressure cylinder and piston,
the supply of steam directly to each of said cylinders and pistons, may be effected
by supplemental passages controlled by the governor valve, in a similar manner.
In the application shown in Fig. steam is supplied to and exhausted from the
piston 11, of the cylinder 12, by a main slide or distribution valve 13, and in the
operation of the engine within the limit of its ordinary or normal capacity, is cut
off at a determined period in the stroke, by an independent cut off or expansion
valve 14, working in a chest 16, above the chest 15, of the main valve, and com-
municating therewith by ports or passages, over which the cut off valve travels.
The main steam passage 5, leads from the governor -valve chest 3, to the cut off
valve chest 16, and the supplemental steam passage, from the governor valve chest
to the main valve chest 15. Under ordinary conditions, the passage 6, being closed,
steam will be cut off at a determined point of the stroke, but upon the opening of
the passage 6, by the governor, on the application of duty or resistance beyond the
normal capacity of the engine when working expansively, steam will be admitted
directly to the main valve chest 15, and will be supplied therefrom, to the
piston 11, during the full stroke thereof, such increased supply continuing until
the passage 6, is closed by the governor, on the relief of the excess of duty imposed
on the engine.
Figures 3 and 4 illustrate the application of my invention to a compound rotary
engine having tren
1:1

page_text: drum 12, secured upon and adapted to rotate with a shaft 13, and carrying a series
of pistons 14, the construction of said engine being fully set forth in another
application for Letters Patent by me. In the normal operation of the engine,
steam is admitted, as before described, through the main steam passage 5, and acts
successively upon the series of pistons of the high pressure cylinder, in the rotation
of the drum. Upon the application of duty greater than the maximum in normal
operation, steam is admitted through the supplemental passage 6, to the exhaust
passage leading to the low pressure cylinders, and acts directly upon the pistons
thereof, as in the former case. The engine may be constructed to use steam
expansively, or cut off at a fraction of the active traverse of its pistons, when in
ordinary operation, and one supplemental passage may be led into the high pressure
cylinder, so as, when opened by the governor valve, to supply steam thereto for the
full stroke or active traverse of its pistons, while a second supplemental passage,
also opened by the governor valve under further increase of duty, supplies steam
directly to the low pressure pistons. Such specific embodiment of my invention
being however, set forth in another application for Letters. Patent by me is not,
per se, claimed as of my present invention.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. The improved method of increasing the development of power from steam
engines, which consists in affording a direct supply of steam coincidently to each of
two or more pistons of a steam engine, in accordance with the application of an
increased duty or resistance thereto, and by mechanism actuated to effect said
supply in and by said application, substantially as set forth.
2. The improved method of increasing the development of power from steam
engines, which consists in affording a supply of steam for the full stroke of the
engine piston, in addition to the ordinary supply for a fraction of the stroke, said
additional supply being effected in accordance with the application of an increased
duty or resistance to the engine and by mechanism actuated in and by said
application, substantially as set forth.
3. The combination, with a compound engine, of a governor, a governor valve,
and passages controlled by said valve and establishing direct and independent
communication from the main steam supply pipe to the receiving side of two or
more pistons of the engine, substantially as set forth.
4. The combination, with a steam engine adapted to work expansively or receive
steam for a portion only of its piston stroke when in ordinary or normal operation,
of a governor, a governor valve, and main and auxiliary passages, each controlled
by said valve and leading, respectively, from the chest thereof to a delivery opening
controlled by the cut off mechanism and to a similar opening independent of said
mechanism, substantially as set forth.