Improvements in Gas Governors.
Year: 1895

page_text: Date of Application, 11th Dec., 1895
Complete Specification Left, 8th Sept., 1896-Accepted, 31st Oct., 1896
PROVISIONAL SPECIFICATION.
Improvements in Gas Governors.
I JAMES MILNE, Milton House Works, Edinburgh, Engineer, do hereby declare
the nature of this invention to be as follows :-
:-
The nature of my invention is the rendering of gas governors automatic,
whereby when an increased consumption renders an increased pressure advisable
the governor will at once respond and give an increased pressure and again reduce
the pressure when the demand declines. I fit above the "bell" of the governor a
horizontal shaft upon which I fix a cycloid path with a balance weight so that at .
various positions the balance weight hangs at varying distances from the centre of
shaft. On this same shaft 1 fix a wheel from the edge of which the cord hangs
which suspends the governor bell. By this arrangement the bell can be partially
relieved of counter-balancing weight as it falls, the balance weight hanging from
the cycloid assuming a position nearer the centre upon which the shaft revolves,
thereby increasing automatically the weight of the bell and in consequence the
pressure the governor allows upon the main.
Alternatively I arrive at this end by any one of the three following means or by
a combination of any or all of them with each other or with the method above
described.
First. I may substitute a chain of the requisite weight to support the balance
weight and do away with the cycloid. The weight of chain on the balance weight
side of the supporting pulley diminishes as the bell falls, thus throwing increased
weight on the bell.
Second. I may fix a heavy arm or weight on the side of the shaft or pulley,
which when standing in a vertical position will exercise no influence, but as the bell
falls will be carried to side of centre of shaft, thus partially counterbalancing the
balance weight and increasing the weight on the bell.
Third. I may make the bell of the governor tapered or of varying areas smaller
at its upper end, the floating power being thus reduced when a smaller area is in.
action at the surface of the sealing liquid.
Dated this Tenth day of December 1895.
I, JAMES MILNE, Engineer, Milton House Works, Edinburgh, 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 :-
The nature of my invention is the rendering of station or other gas governors
automatic, whereby when an increased consumption renders an increased pressure
advisable the governor will at once respond and give an increased pressure and
again reduce the pressure when the consumption diminishes.
In ordinary gas governors the bell is supported partly by the counterbalance
weights and partly by the pressure upon its under side of the gas which has passed
through the cone or other valve.
"

page_text: Immediately increased consumption takes place this pressure diminishes, and the
bell with its pendent cone falls, thus giving a larger area for the passage of gas so
as to raise the pressure again to that for which the governor is set.
As the consumption of gas increases it is necessary to increase the pressure to
enable a proper supply of gas to be maintained to the points of the mains furthest
distant from the governor.
In the ordinary gas governors to obtain this increase of pressure it is necessary
either to load the bell of the governor by means of weights, or to diminish the
counterbalance weights, which operations require to be done by hand and at the
discretion of the attendant.
By means of my invention any decrease of the pressure on the outlet side at
once sets in operation mechanism which automatically gives the necessary increased
pressure above referred to, and likewise reduces the pressure as the demand
diminishes.
I now proceed to describe the various means whereby I propose to accomplish
this object.
In Fig. 1A represents the bell of the governor which rises and falls according
to the outlet pressure, and to which is connected by chain, rod, lever, or other
means the cone B which regulates the flow of gas.
CC represents the ordinary weights used to wholly or partially counterbalance
the bell A and D D are the floats (shewn in dotted lines) which are also frequently
used for the same purpose, either alone or in conjunction with the weights CC.
E is a balance weight suspended by a cord, chain, tape, or other means of
suspension from a helix F, certain parts of whose circumference are at varying
distatices from the centre G upon which it revolves. The helix F is securely fixed
upon the shaft H, to which are also securely fixed the pulleys KK and L from
which are suspended the balance weights and bell.
It is obvious that when the weight E is suspended from a point in the
circumference of the helix F at its greatest distance from the centre G as in Fig. 2
it is neutralising to a much greater extent the effect of the counterbalance
weights CC than when suspended from a point b in the circumference of the
helix Fat its least distance from the centre G as in Fig. 3. Thus the varying
distances of the points of suspension of the weight E from the centre G regulate
accordingly the outlet pressure of the gas.
In determining the rate of increase of the radius of the helix it is necessary to
note the position of the bell and cone when the maximum quantity of gas is
passing through the governor at the maximum pressure fixed upon and also when
the minimum quantity at the minimum pressure is passing. The distance of travel
of the bell between these two extremes and the diameter of the wheel K govern
the rate of increase of the radius of the helix.
Alternatively I arrive at the object of this invention by any one of the three
following means, or by a combination of any or all of them with each other or with
the method above described.
First. I may supersede the helix by constructing the several links of the balance-
weight chain of such equal or varying weights as may in each case be determined
by experiment of calculation to be necessary to ensure that as the bell falls,
drawing with it a portion of the balance-weight chain, the weight of chain on the
counterbalance weight side of the pulley shall be diminished in suitable proportion
and the weight upon the other side increased in such relative proportion thereto as
will automatically give the desired increase of pressure.
Second. I may dispense with the helix by fixing a heavy arm or weight on the
side of the shaft H or pulley K Fig. 4, which, when standing in a vertical position,
will exercise no influence, but as the bell falls will be carried to the side of the
centre of the shaft, as shewn by dotted line at M', thus partially counterbalancing
the balance weight and causing the desired increase of pressure.
Third. Instead of using a helix, special chain or arm, as above described, I may
make the bell of the governor A tapered upward or of varying areas diminishing

page_text: in the direction of its upper end, as shewn in section in Fig. 5, in such a way that
the further the bell is immersed in the sealing liquid the smaller is the area of the
bell at the surface of the liquid exposed to the pressure of the gas-occasioning
the desired larger pressure of gas to counterbalance it.
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.) In a station gas governor the application of a helix or similar arrangement
an increase of
in such a way that the opening of the valve consequent on
consumption automatically causes an increase of pressure as required; all as and
for the purposes hereinbefore set forth and as illustrated by the annexed
drawings.
(2.) In a station gas governor the application of a balance-weight chain upon a
pulley fixed to the shaft actuated by the rising and falling of the bell, the several
links of such chain being constructed in manner hereinbefore described, so that by
its means the outlet pressure is automatically increased or decreased as necessity
requires; all as and for the purposes hereinbefore set forth and as illustrated by
the annexed drawings.
(3.) In a station gas governor the application of a weight fixed upon an arm or
crank in such a way that the opening of the valve. consequent on an increase of
consumption automatically causes an increase of pressure as required; all as
and for the purposes hereinbefore set forth and as illustrated by the annexed
drawings.
(4.) In a station gas governor the use of a bell diminishing in size towards the
upper end whereby as the valve opens the area at the surface of the sealing liquid
is diminished and consequently a greater outlet pressure is obtained; all as aud for
the purposes herein before set forth and as illustrated by the annexed drawings.
(5.) My herein before described apparatus applicable to station gas governors for
automatically increasing and decreasing outlet pressure as required by any increase
or decrease of the consumption; all as described in the foregoing specification and
illustrated by the accompanying drawings.
Dated thi. Fifth day of Santember 1896
JAMES MILNE.