Improvements in the Inlet Valves of Steam Engine Cylinders and in Mechanism for Actuating the said Valves.
Year: 1897

page_text: Improvements in the Inlet Valves of Steam Engine Cylinders and
in Mechanism for Actuating the said Valves.
I, ALFRED HOYOIs, of Clabecq, in the Kingdom of Belgium, 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 :-
My invention relates to inlet valves of steam engine cylinders and has for its
object to considerably reduce the rise of these valves and their dimensions and
hence to diminish injurious spaces and cooling surfaces.
To this end my invention consists of a valve with a plurality of seats the rod of
which is capable of moving independently of the valve when the latter is in its
closed position and of actuating mechanism connected to the said rod and designed
to reduce to a minimum the independent motion of the said rod.
In order that my invention may be readily understood, I will describe it with
reference to the accompanying drawings in which
Figure 1 is an elevation partly in section on the line A B Figure 3 showing a
portion of a steam engine cylinder provided with two valves having two seats
and actuating mechanism constructed according to my invention.
Figure 2 is a front elevation of a portion of one of the ends of a cylinder furnished
with two valves arranged side by side.
Figure 3 is a plan view of the arrangement illustrated in Figure 1 showing the
actuating mechanism of the valves.
Figure 4 is a section of a modification of the valve Figure 1.
Figures 5 and
are sections of a valve having four seats the said valve being
shown in its open and closed positions.
Figures 7 and 8 are corresponding views of a valve having six seats.
The same letters and figures of reference indicate corresponding parts in all the
figures of the drawings.
The valve has a number of seats either two as shown at a a¹ in Figures 1
and 4 or four as shown at a a¹ a² a³ in Figures 5 and 6 or six as shown
at a a¹ a as a' as in Figures 7 and 8 or the valve may have more seats the
number being limited only by practical difficulties of construction. The seat a is cast
[Price 8d1

page_text: in one with a cylinder or drum b on which slides the valve c. In the construction
shown in Figure 1 the rod d of this valve is connected to the actuating lever e
and passes freely through a socket r in the centre of the said valve. This rod d
has a collar q made on it and is surrounded by a spiral spring p placed between
the said collar q and the socket and is furnished at its free end with a washer s.
This arrangement allows the rod d to move independently of the valve when the
latter rests on its seat. The effect of the said arrangement is that when the valve
has been closed by forward motion of its rod d and has come to rest on its seat
the said rod continues its forward motion to the end of its stroke causing the
spring p to be compressed and during backward or return motion of the said
rod the valve is not carried with it until the washer & bears against the rear
part of the socket r. The spring p assists the motion of the rod during the first
portion of its return stroke and the arrangement ensures effectual closure of the
valve and prevents it from being broken upon its seat.
Figures 45, 6, 7, and 8 illustrate a modification of the valve above described
specially applicable when the valve is actuated by a trip motion.
In this case the rod d is not moveable relatively to the valve the collar q of the
rod d bears upon the socket r of the valve and the coiled spring p is placed
between the collar q and another collar t¹ around the guide t of the rod d.
As shown in Figures 1, 2 and 3 each of the valve rods Figures 1, 2, 5, 6, 7 and 8
is actuated by a lever arms at the head of which is fixed the end of the rod d.
The lever arm e is formed integrally with a piece f sliding upon a cylindrical
support and receiving rectilinear to and fro motion from a rod n to
which it is fixed. The rod n which slides in a support o receives its to and fro
motion from a connecting rod m one end of which is jointed to this rod n and the
other end of which is jointed to one of two arms 11 of a lever k keyed on a shaft j
to which a lever i communicates oscillatory or rocking motion when actuated by a
connecting rod the head of which is jointed at h. This connecting rod receives
to and fro inotion from an eccentric keyed on the driving shaft or from the link
motion of the engine in the case of one furnished with a reversing gear, as will be
readily understood.
The arms or branches of the lever h form such an angle to each other as to
minimize motion of the rod d while the valves are closed when the said rod moves
independently of the valve.
When two valves are used at each end of the cylinder as shown in Figures 2
and 3 the piece f is forked and to the respective branches ee of the fork the end of
the rod of one of the valves is secured but if only one valve is used the piece ƒ has
but one lever arm e as in Figure 1.
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 I
claim :-
First: A valve for inlet of steam to the cylinders of steam engines characterized
by a plurality of seats allowing steam to enter at one and the same time through a
great number of ports or openings and to thus considerably reduce the rise of the
valve for admission of steam, substantially as hereinbefore described and illustrated
in Figures 1, 4, 5, 6, 7 and 8 of the accompanying drawings.
Secondly: A circularly seated simple or multiple valve for admission of steam
into the cylinders of steam engines characterized by an actuating rod furnished
with a spring connected to the valve in such a manner as to be capable of moving
independently of the said valve while compressing the spring after having closed
the valve during its forward motion extension of the said spring taking place
beforo the valve is opened during rearward motion of the said rod substantially as
herein before described and illustrated in Figure 1, of the accompanying drawings.
Thirdly-The modification of the valve referred to in the second claim in which
modification the valve rod is fixed to the valve and furnished with a spring which

page_text: it compresses while opening the valve substantially as hereinbefore described and
illustrated in Figures 4 5, 6, 7 and 8 of the accompanying drawings.
;-
Fourthly The actuating mechanism of the rod of the valve referred to in the
second claim characterized by a lever having two arms forming between them
a determined angle and to each of which is jointed a connecting rod transmitting
to the rod of one of the cylinder valves or to the rod of two or more coupled valves,
a to and fro motion communicated to the said connecting rod by oscillation of
the two armed lever which is actuated by the driving shaft, substantially as
herein before described and illustrated in Figures 1, 2 and 3 of the accompanying
drawings.
Dated the Seventh day of December 1897