Improvements. in. Reducing Valves.
Year: 1896

page_text: Date of Application, 23rd Jan., 1896-Accepted, 29th Feb., 1893
[Communicated from abroad by the Firm of SCHAFFER & BUDENBERG, of
Buchau, near Magdeburg, in the German Empire, Engineers.]
Improvements. in. Reducing Valves.
I, WILLIAM EDWIN HEYS of 70 Market Street Manchester in the County of
Lancaster, Chartered Patent Agent, do 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 :-
This invention relates to reducing valves and its object is to secure.greater
efficiency and certainty in operation.
A reducing valve constructed according to this invention consists of a suitable
casing with a high pressure inlet and a low pressure outlet. In the lower part of
the casing there is a piston or a diaphragm which is normally forced upward by an
adjustably weighted lever or by an adjustable spring. Above the piston there is
a diaphragm or horizontal partition dividing the high pressure side from the low
pressure side of the valve, and through which two or more openings are formed,
these openings being closable by valves having stems of different lengths projecting
towards the face of the piston. The valves are so arranged that the high
pressure tends to close them."
In action, the low pressure acts on the face of the piston or equivalent diaphragm,
tending to force it downwards, but the weighted lever tends to force it in the
opposite direction and is so weighted or adjusted as to lift the piston or diaphragm
when the pressure on the low pressure side falls below the predetermined amount,
and the contrary. When the piston is thus lifted it acts first upon the valve
having the longer or longest stem and opens that valve. Should the steam thus
admitted to the low pressure side be insufficient, the motion of the piston is
continued and opens the valve having the next shorter stem, and after this, if the
pressure on the low pressure side is still below what is required, it successively
opens the remaining valves where there are more than two. When the pressure
on the low pressure side is in excess of what is required, the valves are successively
closed by the reverse motion of the piston.
Figure 1 of the accompanying drawings illustrates a reducing valve constructed
to embody these improvements, in vertical cross section.
Figure 2 represents a plan of the valves, seven being employed in the apparatus
illustrated and hereinafter described with reference to the drawings.
A is the valve casing, I the high pressure inlet, and O the low pressure outlet.
D is the diaphragm or horizontal partition having passages therethrough fitted
with valves V having stems S of different lengths. The piston P is held in
equilibrium by the weight W on the lever L or by means of an adjustable
spring as is well understood. The high pressure steam entering at I as indicated
by the arrow, presses upon the valves V and tends to keep them closed, but when
the piston P lifts, it first touches and opens the valve V having the longest stem
and then, the lifting being continued, it touches and opens the other valves in
succession as hereinbefore described. The last of the valves is not opened until
the piston has nearly completed the whole of its lift.
Since the diameter of the piston P is very large as compared with one of the
valves V, only a slight reduction of pressure on the low pressure side is necessary
to raise one of these valves, but the moment it is opened, the whole pressure on the

page_text: inlet side no longer acts upon it, the valve having a tendency to be drawn down
only by the friction of the steam passing it. The same observation therefore
applies to the remaining valves. The resistance therefore which the piston P
encounters in its movement from the lowest to the highest position is comparatively
small, and it is thus called upon to exert a much less force upwards than would be
necessary if, instead of the plurality of valves there were only one large valve
having the same area as the combined area of all the small valves V. It follows
that a comparatively small reduction of pressure on the outlet side can effect an
opening of all the valves V. As the pressure tends to increase on the outlet side,
the reverse takes place, and the valves V close one by one until the desired pressure
is established on the outside.
Although a piston P is represented in the drawings as the agent by means of
which the valves V are operated, it will be understood that as in other types of
reducing valves, an equivalent flexible diaphragm or the like may be employed, and
it is to be understood therefore that this invention is not limited to reducing valves
in which a piston is employed.
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. A reducing valve constructed arranged and operated substantially as herein-
before described with reference to the accompanying drawings.
2. In a reducing valve, the combination and arrangement of a plurality of
valves having stems of different lengths arranged in a diaphragm or horizontal
partition, with a piston or flexible diaphragm or the like adapted to be lifted
and lowered by a weighted lever or spring and acting successively upon the valves,
substantially as hereinbefore described and as illustrated by the accompanying
drawings.
Dated this 22nd day of January AD 1896
WILLIAM E. HEYS.