AN IMPROVED STEAM GENERATOR AND ENGINE
Year: 1880

page_text: LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and
Company, Solicitors of Patents, of 67, Strand, in the City of Westminster,
Civil Engineer, for an Invention of "AN IMPROVED STEAM GENERATOR
AND ENGINE," A communication from abroad by Wilhelm von Pittler, of
Gohlis-Leipzig, in the Kingdom of Saxony.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at
the Office of the Commissioners of Patents on the 13th October 1880.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors
of Patents, of 67, Strand, in the City of Westminster, Civil Engineer.
"AN IMPROVED STEAM GENERATOR AND ENGINE." [A communication from abroad
by Wilhelm von Pittler, of Gohlis-Leipzig, in the Kingdom of Saxony.]
The Invention relates to a combined steam generator and engine, and consists
chiefly in generating steam by injecting or pumping into a strong metallic vessel
the water necessary for each stroke of the engine, the said vessel or evaporator
being preferably made of cast iron and heated so as to immediately evaporate the
water injected and convert it into high pressure steam, which is then conducted to
the engine.
Also in constructing the furnace in such a manner that the combustion chamber
surrounds the evaporator, but is itself surrounded by a mantle in which the feed
water circulates before being pumped into the evaporator, the gases of combustion
being preferably made to pass from the combustion chamber into a flue surrounding
the feed water mantle and around the latter into the chimney.
The feed water mantle communicates with a feed pump driven by the engine,
and also with a high level reservoir, the feed pump having two barrels and pistons
driven from the same connecting rod and cross head, either of which pistons may
be set in operation, while the other is a reserve piston.
The governor of the engine acts simultaneously as a steam valve and a feed water
valve. The governor may be a centrifugal governor with horizontal shaft, the
pendulous arms of which move a conical slide along the shaft, thereby setting in
motion a lever which is connected with the steam valve and also with the feed water
valve, the return motion of the said lever being effected by a spring.
The engine is preferably vertical and bolted on the top of the generator.

page_text: F
10 the feed water neater.
3. To the steam inlet.
4. To the water inlet.
The general operation of the apparatus is as follows:-
The thickwalled cast iron receptacle A is heated to red heat, after which water
is injected by means of the pump B, which water escapes through the perforations
of the pipe C, and is rapidly converted into high pressure steam by its contact with
the inner walls of A. The steam thus generated is made to act on the piston E in
the steam cylinder D, thereby setting the crankshaft F in motion.
The generator A receives only a small quantity of water at a time, that is to say,
as much as (or little more than) is necessary to produce the steam required for
every stroke. The walls of A are made very strong in order to tako up a large
quantity of heat at the beginning of the operation. The generator A is closed by a
cover G through which pass the feed water pipe and the steam pipe. This cover
carries also an ordinary pressure gauge M, a pyrometer H, and an ordinary safety
valve S. The pyrometer H indicates the temperature of the steam contained in the
generator A. The furnace consists of the grate J and the casing K which surrounds
the latter, and has two compartments Land N, of which L serves as a receptacle for
the feedwater to be heated, while the outer space N forms a flue for the gaseous
products of combustion, which pass into N at a, and are forced by a partition to
travel around the whole casing K before they can escape into the chimney at c.
The heated feedwater is drawn off by the feed pump B and forced through the
pipe C, which distributes it towards the walls of the receptacle A where it evapo-
porates. To avoid the necessity of letting the pump B act by suction the feedwater
heater or space L is put in communication with a high level reservoir, and an
ascension pipe d is applied through which the water enters the pump after having
passed through the regulating valve u. The punp B has two barrels and valve
boxes, so arranged that one of the cylinders forms a reserve pump while the other
is in action, under ordinary conditions.
The pistons e¹, el, are ram pistons guided at their upper ends in a cross head f
which is so connected with the pistons that it imparts motion to one or other of
the two pistons, according to requirements. The coupling of the pistons is effected
by passing a pin through one of the sleeves of the cross head f and through a
corresponding opening of the piston rod which belongs to this sleeve, thereby
establishing a rigid connection between the cross head and the piston to be set in
action.
The pump B receives its motion from the eccentric g. The distribution of
the steam in the cylinder is as usual, but the valve gear has some peculiarity, the
governor R being driven from the crank shaft and constructed as follows:-The ball
arms m are connected with the conical sleeve n, mounted on the governor shaft
and movable along the latter. The sleeve n is connected with the lever o, which
carries at its other end the rod t leading to the slide valve q situated in the valve

page_text: chest. As soon as the governor is made to act by an increase of speed, the conus n
is shifted, and thereby the lever o moved so as to lower the slide valve q and
diminish the area of the steam inlet. The diminution of the steam inlet is accom-
panied by a diminution of water inlet, because the water valve u is attached to the
rod t by means of a cross piece v, so as to share the motion of the steam valve. It
is also opened and closed by means of the governor R, lever o, rod t, and helical
spring r.
The spring lifts the two valves as soon as this is permitted by the position of
the conical sleeve n on the governor shaft.
The improvements in the steam engine illustrated by Figs. 1-3, Sheet II. are
as follows-Instead of the feedwater heater L enclosed by the casing K, a system
of pipes i, i, is applied surrounded by a wrought iron casing. The steam cylinder D
projects into the generator or superheater A, thereby dispensing with steam
pipes between generator and cylinder. The steam is generated in the following
manner: The pump B forces the feedwater which has previously passed through
the heater G into the pipes i, i, where it is evaporated. The pipe c' has a larger
diameter than the pipes i, i, and has for its object to evaporate any water carried
with the steam before it enters the superheater A.
The pipe contains a float which indicates the water level on a scale, and may
be connected with the pump so as to stop the latter until the normal evaporation in
the pipes is re-established.
From the pipe the steam enters the superheater A to be superheated, from
where it is admitted to the steam cylinder D, according to the position of the slide
valve, the steam cylinder being supported by the flange of the superheater A.
The waste steam escapes from the cylinder through the exhaust pipe H and
through the feedwater heater G into the atmosphere.
H. J. HADDAN. (L.S.)