IMPROVEMENTS
Year: 1879

page_text: PROVISIONAL SPECIFICATION left by Albert Krank at the Office of the
Commissioners of Patents on the 3rd June 1879.
ALBERT KRANK, of 39, Moreton Terrace, Pimlico, S.W.
PUMPING AND OTHER ENGINES."
"IMPROVEMENTS IN
My Invention has for its object the improvement of direct acting engines so as
to make them use the steam expansively in a single cylinder with one steam
moved valve, and to govern their motion themselves without any gear either for
the governor or the valve.
The Suomi pumping engine consists of a common steam cylinder with a valve
chest containing a single slide valve with either plain or cylindrical face, a common
pump-cylinder with necessary valves and air vessel connected to the steam
cylinder by means of a distance piece, or a bed plate, or both. The pump piston is
connected directly to the steam piston by a piston rod, and the thus connected
pieces move altogether by themselves without in anyway interfering with the valve
motion.
The single slide valve is moved entirely by the steam without any tappets or
valves. For giving the motion to the valve there is at each end of it a plunger
fitting into a corresponding cylinder at the end of the valve chest. In the bottom
of each valve-cylinder are three holes of which the innermost lead to the exhaust
and the outer ones to different parts of the steam cylinder. In the bottom of each
plunger is one hole leading to the back of it, which when the valve moves passes
over the holes in the cylinder bottom. Except through this hole there is no con-
nection between the steam cylinder and the valve cylinder as the plunger covers
the holes. If one end of the steam cylinder is named "the front end" and the
other the "back end," the valve cylinders in the same way and the holes in the
cylinder bottoms are numbered from the ends towards the centre, then the holes
1 and 2 in both valve cylinders lead to the steam cylinder and the holes 3 to the
exhaust, and the action of the steam on the valve is as follows :-
=
When the piston is at the front end of the stroke the valve is at the back end
admitting steam to the front and exhausting it from the back. The hole in the
front plunger is over the hole 3 in the front valve cylinder, so that the steam
previously behind the plunger passes into the exhaust, and the hole in the back
plunger is over the hole 1 in the back cylinder. When the piston has passed a
short distance the steam behind the piston gets through a hole in the cylinder
barrel, and the back hole 1 behind the back plunger pushing the valve towards the
Price 21

page_text: front. As soon as the valve has passed so far that the hole in the back plunger is
over the hole 2 in the back cylinder which leads to the end of the exhaust part of
the steam cylinder, the steam rushes away and the valve stops closing the steam
admission to the front and leaving the exhaust from the back full open. The
steam in the front end of the steam cylinder then expands during the rest of the
stroke, and when the piston reaches the back end the steam gets into the hole 2 and
finishes the stroke of the valve, so that steam is admitted through the back port
and exhausted through the front port. The holes 1 and 2 in the front valve
cylinder can be arranged so that the back of the front plunger is not in connection
with the steam in the cylinder before the valve has opened the corresponding
exhaust, and any disturbances can thus not occur in the valve motion. The action
of the steam on the valve is the same during the back stroke. In starting the
engine the valve is moved the first time by a hand lever.
If the engine is to be made to work without expansion the holes I are left away,
and the holes 2 skifted in their places. If the engine is to work with fixed
expansion the above arrangement is sufficient. A variable expansion regulated by
a gearless governor is provided in the following way :-
one.
To the cover of one of the valve cylinders a small cylinder is fixed. In this
cylinder a piston works which is connected by a rod to the valve plunger and moves
thus with the valve. The ends of the small cylinder are connected by a canal in
the side, which is closed more or less by a small sluice. At the end of the sluice
rod there is a piston working in a second small cylinder which is fixed to the first
The bottom of the second cylinder is through a small pipe in connection
with the delivery pipe above the air vessel, and the head thus always tries to press
the second piston upwards and shut the sluice. The second piston is kept down by
a spring which is adjustable by a handle. The water which leaks through the
second piston is taken away by a pipe fixed to the top of the second cylinder, and
the water can, through a hole round the sluice spindle, fill the first cylinder. When
the slide valve moves the first piston there is a certain resistance when the water
shall pass the sluice, which resistance increases if the sluice through increase of the
head is lifted higher, and decreases if the water pressure decreases either by lessened
head or thro' an increase of velocity in the delivery pipe caused by greater
pressure of the steam. The cut off is thus later if the head is greater, and quicker
if the steam pressure is greater. When the spring is adjusted so that the engine
runs with a certain speed it will govern itself under any circumstances. To allow
the valve to pass quicker at its second motion when the steam admission shall
occur, there are in the first cylinder besides the connection past the sluice also con-
necting canals from each end to the points corresponding to those where the valve
stops for expansion. These canals are shut either by one drop valve at the centre
opening inwards, or one at each end opening outwards, so that all the water must
pass the sluice at the first part of the valve stroke, and at the second part can take
an easier way.
The above mentioned valve gear can of course even be applied to engines for
other purposes, and another cylinder added to the engine to make it compound.