An Improved Valve Motion for Steam Engines.
Year: 1890

page_text: Date of Application, 24th July, 1890
Complete Specification Left, 23rd Apr., 1891-Accepted, 23rd May, 1891
PROVISIONAL SPECIFICATION.
An Improved Valve Motion for Steam Engines.
I, Alfred GuHRAUER of Budapest in the Empire of Austria-Hungary,
Engineer, do hereby declare the nature of this invention to be as follows:-
:-
The object of this invention is a valve motion in which the opening and
closing of the valve takes place spontaneously during the whole stroke by lever
movement.
The improved arrangement is in the main as follows:-
The motion of an excentric is transmitted through a cross lever to a lever from
about the middle of which the valve lever and valve are movably suspended.
Between one extremity of said cross or. cam lever and one end of the valve lever,
a spring box is inserted hinge-fashion, while a similar but stationary spring-box is
provided on the other side of the valve lever where the latter has its fulcrum and
is connected hinge-fashion with a pin which is movable to a limited extent in said
box and is surrounded by a spiral spring. The spring-box on the other side is of
similar construction but its pin is connected with the cam lever, while the box
proper is attached to the respective end of the valve rod lever. Each of said
spiral springs tends to press a shoulder, provided on its pin, from outside against the
cover of the spring box.
On the cam lever moving upward, the valve rod lever is raised about its fulcrum,
thereby lifting the valve, while by the reverse movement the valve is closed. As
soon however as it bears on its seat, the hinge connecting the valve rod with its
lever and that connecting the latter with the pin of the stationary spring box
interchange their respective functions, the former hinge acting now as lever fulcrum,
while the latter, i.e. the hinge that hitherto served as fulcrum, is raised and com-
presses the respective spiral spring, until a shoulder or projection provided inside
the box on the pin abuts against the cover of the box.
On subsequent further downward movement of the cam lever, the spring in the
other box is compressed. The valve consequently rests softly but powerfully on
its seat under pressure from two springs.
The reverse movement of the cam lever having an analogous effect, it is evident,
that also the closing of the valve is not effected by means of springs but direct by
lever movement, while the action of the springs only commences after the valves
are closed.
The tension of the springs naturally depends on the stuffing-box friction and the
steam counter pressure.
1000
HUELSER & Co.,
Attorneys.
COMPLETE SPECIFICATION.
An Improved Valve Motion for Steam Engines.
I, ALFRED GUHRAUER, of Budapest in the Empire of Austria-Hungary,
Engineer, 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 :-
All valve motions, where the valves are raised and lowered direct by the move-
ment of an eccentric and where the variation in the supply only takes place
simultaneously by a change in the eccentricity or in the angle of lead or in both,
are, in their mode of action, exactly similar to the simple slide valve motion.
A dead point, situated between the levers which are used in the former kind of
LD

page_text: valves, corresponds to the inner and outer casing of the latter kind of valves, and
this dead point must always be traversed before the valve can be raised. But the
consequence of this dead point is that the valve, on the reversal of movement,
must be closed by spring pressure and not spontaneously by the motion of the
levers.
The object of this invention is to provide an arrangement of valve motion in
which the opening and closing of the valve take place spontaneously during the
whole stroke by lever movement.
The improved arrangement is in the main as follows, reference being had
to the accompanying sheet of drawings and to the letters of reference marked
thereon:-
The motion of an eccentric is transmitted by means of a cross lever a through the
hinge joints e el to a lever b pivotted at c, whilst the hinge joint d forms the suspension
point of the valve V.
e
The transmission of the motion through e e', as well as through the hinge joint c,
is rendered elastical by means of inserted spiral springs g g', placed in the spring
boxes. The hinge joint c ends in the plate shaped projection f, which is
constantly pressed by the spring g against the cover of the box. The hinge
joint is of similar construction, the projection f¹ of which is pressed against the
cover by means of spring gl. If the lever arm a now move from below upwards,
the lever is raised on the hinge joint c and lifts simultaneously the valve V. By
a reverse movement, the valve is closed, but, as soon as it rests on its seat, the
hinges c and d exchange their functions, in that d cannot move further downwards
and becomes the fulcrum on which e is raised, whereby the spring 9 is so far
stretched that the projection k, attached to the pin l, rests against the cover i. As
thereby the position of c is fixed, on the subsequent further downward movement of
the lever a, the spring gl comes into action whilst the same is compressed.
C
The valve consequently rests gently but powerfully on its seat under the pressure
of the tension of two springs.
On the reversal of the motion, lever a rises with dead movement so far until f¹
strikes on, then the lever b is raised on the hinge joint d so far until the pro-
jection of the hinge joint c rests against the cover i. From this time forward,
c again acts as fulcrum on which 61 further turns and raises the valve. The play
of the valve is, therefore, during the whole stroke, spontaneous, in such a way that
the closing is not brought about by means of springs but direct by the movement
of the levers, while the action of the springs only commences after the closing of
the valves. The tension of the springs depends on the friction in the friction boxes
and the counter pressure of the steam.
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 valve motion for steam engines consisting of a lever, actuating
the valve rod, in combination with the adjustable fulcrum c and suspension point d,
such lever, fulcrum and point being combined in such a way that alternately
c and d form the fulcrum of the lever, substantially as hereinbefore described and
shown.
2. In a valve motion for steam engines such as described in Claim 1, the insertion
of springs between the point c¹ and fulcrum c and points e e¹ of the levers a b, in
such a way that, on the valve resting on its seat and on the further movement of
the lever, first one and then the other spring is compressed, substantially as herein-
before described and shown.
Di 11
T
A
1 1001
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.