NEW OR IMPROVED SELF-ACTING EXPANSION GEAR FOR STATIONARY STEAM ENGINES
Year: 1876

page_text: LETTERS PATENT to Max Alexander Starke, in the City of Hirschberg, Kingdom
of Prussia, Empire of Germany, for the Invention of "NEW OR IMPROVED
SELF-ACTING EXPANSION GEAR FOR STATIONARY STEAM ENGINES."
Sealed the 22nd August 1876, and dated the 28th February 1876.
PROVISIONAL SPECIFICATION left by the said Max Alexander Starke at the
Office of the Commissioners of Patents on the 28th February 1876.
MAX ALEXANDER STARKE, in the City of Hirschberg, Kingdom of Prussia, Empire
of Germany,
"NEW OR IMPROVED SELF-ACTING EXPANSION GEAR FOR STATIONARY
STEAM ENGINES."
This Invention is applicable to all machines with valve gear, machines with
horizontal or vertical steam cylinders, to lever engines with one cylinder, or to
compound engines.
The principal parts of the gear are, 1st, a valve chest with expansion valve and
disposition of stroke; 2nd, gear with pawls and disposition of regulation.
The application of the apparatus which forms in itself a separate applicance can
be effected in most cases without any difficulty, necessitating only the adjustment
of the valve chest and some alteration of the pipes connected therewith; alterations
of existing construction do not extend further than to the suspension of the old
expansion and throttle valve, and the distribution of steam is effected by the main
slide in the ordinary way.
The box of the new expansion valve is bolted to the flange of the old valve chest
instead of the throttle valve in such a way that the valve stands vertically. The
lifting of it is quickly effected by the expansion gear at each stroke, and so that it
remains unaltered in an open position during the period of full pressure; the
shutting of the valve depending on the governor. The steam expands after the
shutting of the valve up to the moment when the main valve closes the steam port, a
certain quantity of expanded steam being now in the valve chest, which steam is
utilized for the next stroke, and is instantly supplemented by fresh steam, as at
this moment the valve again opens to take up the corresponding open position for
the following stroke.

page_text: It is evident that no disadvantage to the economy of steam and effect will arise
from the position of the expansion valve outside the valve chest, it being necessary
only to reduce this space to the smallest possible dimensions so as not to have too
nuch power for the machine when it is driving the shafting only, because the steam
filling it must absolutely take effect in the steam cylinder, even if the expansion
valve would again shut at the beginning of the stroke. The space in the valve
chest must therefore be filled up by fastening a hollow box of cast iron to the
inside of the lid after removal of the old expansion valve, so as to have over the
back of the main valve only the required space for the passage of steam.
The action of the governor is effected by disengagement of a disposition of click
and ratchet wheel.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Max Alexander Starke in the Great Seal Patent Office on the 28th
August 1876.
MAX ALEXANDER STARKE, in the City of Hirschberg, Kingdom of Prussia, Empire
of Germany. "NEW OR IMPROVED SELF-ACTING EXPANSION GEAR FOR STATIONARY
STEAM ENGINES."
This Invention is applicable to machines with valve gear, machines horizontal or
vertical steam cylinders, to lever engines with one cylinder, or to compound
engines.
The principal parts of the gear are, first, a valve chest with expansion valve and
disposition of stroke; and second, gear with pawls and disposition of regulation.
The box of this improved expansion valve is bolted to the flange of the old valve
chest instead of the throttle valve in such a way that the valve stands vertically.
The lifting of it is quickly effected by the expansion gear at each stroke, and so
that it remains unaltered in an open position during the period of full pressure; the
shutting of the valve depending on the governor. The steam expands after the
shutting of the valve up to the moment when the main valve closes the steam port,
a certain quantity of expanded steam being now in the valve chest, which steam is
utilized for the next stroke and is instantly supplemented by fresh steam, as at this
moment the valve again opens to take up the corresponding open position for the
following stroke.
It is evident that no disadvantage to the economy of steam and effect will arise
when the position of the expansion valve outside the valve chest, it being necessary
only to reduce this space to the smallest dimensions so as not to have too
much power for the machine when it is driving the shafting only, because the steam
filling it must absolutely take effect in the steam cylinder, even if the expansion
valve should again shut at the beginning of the stroke. The space in the valve
chest must therefore be filled up by fastening a hollow box of cast iron to the
inside of the lid after removal of the old expansion valve, so as to have over the
back of the main valve only the required space for the passage of steam.
The action of the governor is effected by the disengagement of a ratchet wheel
and catch.
A special arrangement of this improved gear is represented in the annexed Drawing,
wherein is shewn two different constructions of expansion valves, one serving for
application to machines with vertical cylinders, and is illustrated in Figs. to 6, the
other for application to machines with horizontal cylinder, and is illustrated in
Figs. 7 to 9.
In the first case the valve box a of an outer and an inner chamber, the
latter capable of being shut off by a doubble seal valve b. The steain from the boiler
first enters the outer chamber and opens the valve through the upper and lower

page_text: passage, (same being open at that time,) thence into the inner chambers and to the
valve chest.
In the second case, where the box is generally bolted to a vertical flange of the
valve chest, it is divided into an upper and lower chamber, and these are separated
by a doubble seal valve in shape of a tube hanging into the lower chamber. On
lifting this valve the steam filling the upper chamber falls through the valve into
the valve chest lying underneath. The lifting of this valve is effected by a cast
steel rod, which in the first case without any other connection supports the valve,
while in the second one it is firmly attached to it. The rod clying centrally in
the line of the axis of the valves are guided on one side by stuffing boxes fixed to
the case lids, and on the other side in small air cylinders d, and are here provided
with air pistons e and springs f which effects the closing of the valves. The lifting
of the rods is effected by means of short and strong levers; one of them g made
of steel supports one end of the rod, while the other and opposite end is in direct
connection by a link with the cam shaft of the expansion gear.
The expansion gear is arranged in the following manner:-The post or column
of the governor is bolted to a strong foundation plate h, the foot being shaped
as a fork and holding two brackets cast on it, which brackets carry a short cast
iron excentric shaft i. The two centres of the excentric discs are placed in
opposite directions, and said shaft commanded by simple transmission from the
main shaft performs the same number of revolutions as the driving shaft of the
machine and transmits the movements by bevil gearing to the governor.
The two excentrics have to perform the lifting of the expansion valve according
to the direction of their motion. For this purpose a cam acts for every stroke on a
small slide k working in planned guides and carries on a steel pivot, and capable of
turning thereon a metal catch b, the working parts of which are faced with hardened
steel plates.
When the slide k advances these catches touch the cheeks m
which are screwed to the rods m, which are screwed to the rods n, said rods being
guided at one end in socketed holes of the slide k, and at the other end in a
cylinder o in which they are provided with a welded hollow piston upon which a
spring u acts, same being sunk into the cylinder. On these rods are screwed metal
cliceks in front of the entrance into the cylinder o which move in planed guides
of the cylinder foot p, and act in moving forward by means of short faces upon
the cam shafts t which are provided with steel runners 8.
During the advancing of the rod the valve is lifted for each stroke by the one or
other cheek, the spring w in the cylinder is compressed, and at the same time air
is drawn into the cylinder.
The opening of the valve lasts only so long as the pulley 8 rolls upon the upper
face of the cheek q and the catches are the forward motion inserted, and on their
disengagement they act upon the governor by a key u fixed to its link, and it
fastens a piece o in such position that the catches must go down, and thereby
disengage their ends, whereupon the compressed spring comes into action, the
expansion rod quickly regains its original position, the cam shaft is lowered, and the
valve shut. These motions are carried out with ease and precission, and the
compressed air employed avoids any shock to the valve and valve rod.
The same apparatus with slight modifications only can be applied to new steam
engines, with lying cylinders as one of the best expansion gears, and they show
with it an effect at least as high as the best Corliss machine. In this case the
expansion valve b is only inserted into the body of the slide and makes with it the
same movements. Slide and valve are then surrounded by the valve chest into
which the steam from the boiler enters, and the lifting of the valve is effected by a
rod entering through a stuffing box into the valve chest, the upper end of this rod
being provided with a cross plate of steel upon which the rod slides during the to-
and-fro motion of the valve, and this rod or link also made of steel forms the
intermediate link between the lifting rod and the valve, and is carried in a
concentric guide to protect the valve from wear under the to-and-fro motions.
opening in the upper side of the valve chest gives easy admission to the valve.
An

page_text: Having now described the nature and particulars of the said Invention in such
wise that it may be carried into practical effect, I claim the new or improved self-
acting expansion gear for stationary steam engines, substantially as set forth.
In witness whereof, I, the said Max Alexander Starke, have hereunto set my
hand and seal, this Twenty-fifth day of August, in the year of our Lord One
thousand eight hundred and seventy-six.
MAX ALEXANDER STARKE. (L.S.)