Improvements in Means or Apparatus for Automatically Varying the Load and Pressure of Gas Governors.
Year: 1898

page_text: Date of Application, 28th June, 1898
Complete Specification Loft 97th Anr 1800 Accerted 27th May. 1899
PROVISIONAL SPECIFICATION.
Improvements in Means or Apparatus for Automatically Varying the
Load and Pressure of Gas Governors.
WILLIAM COWAN, Buccleuch Street Works, Edinburgh, North Britain, Gas
Meter Manufacturer, etc. I do hereby declare the nature of this invention to be as
follows:
-
In my Patents, dated May 24th 1892 No. 9829, and October 21st 1892,
No. 18,855, I described my system, of regulating the loading & unloading of gas
governors by means of the pressure of gas in a remote district. In the latter of
these two specifications, an electrical means of communication, between the
auxilliary gas holder, (or pressure vessel), in the distant locality, and the governor,
-in the gas works, or elsewhere,—
,—was described. It is to this part of the invention
that the present improvements relate.
In this invention, I propose to dispense, as far as may be practicable, with the
wires employed hitherto, for electrically bridging the distance between the governor
room & the distant "pressure vessel: " and to employ,--instead thereof, where,
and to the extent applicable, or desirable, a system of wireless telegraphy," (suel.
as has been, and now is, at work, experimentally, between Bournemouth and
the Isle of Wight, and elsewhere); suitable apparatus & arrangements, necessary
for the working of the system, and for its adaptation to, and combination with,
my system of pressure regulation being provided.
Dated this Twenty-seventh day of June 1898.
Improvements in Means or Apparatus for Automatically Varying the
Load and Pressure of Gas Governors.
I, WILLIAM COWAN, of Buccleuch Street Works, Edinburgh, Gas Meter Manu-
facturer, 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 automatic gas pressure controllers of the general type
described in my Patents Nos. 9829 and 18855 of 1892, and more particularly to
the electrically operated type described in the latter specification. In the method
of operation there described, electric connecting wires are used between the
auxiliary gas-holder or pressure regulating vessel in the remote district, and the
electrical device controlling the governor loading at the supply station.
The object of my present invention is to dispense with these connecting wires.

page_text: My present invention consists in varying the load on a gas pressure governor at
the supply station by means of electrical impulses transmitted from a pressure
regulating vessel in the remote district by space telegraphic methods without line
wires.
My invention may be carried into effect by any of the well-known methods,
such as (1) the earth current or leakage method; (2) the magnetic induction
method, or (3) the Hertzian wave method. I will, however, only describe one
method of carrying out my invention, that, by means of the third, or Hertzian wave
method.
Referring to the accompanying sheet of drawings:
Figure 1 shows a diagrammatic view of my gas pressure governor, with the
water loading and unloading valves, and electro-magnets for operating them.
Figure 2 shows a space telegraphic receiver, adapted to supply current by its relay
to the electro-magnet operating the governor loading valve.
Figure 3 shows a similar space telegraphic receiver similarly supplying current
by its relay to the electro-magnet operating the governor unloading valve.
Figure 4 shows my pressure regulating vessel as used at the remote district
to control the pressure of supply from the station.
These drawings are only diagrammatic.
In Figure 1, A is the governor bell, which is loaded by means of an electro-
magnet B, opening a water supply valve C, and unloaded by means of an electro-
magnet B, opening an exhaust valve C which draws off water from the bell through
a syphon tube. The circuit of the valve electro-magnet B is completed by wires
from its terminals E and F to the terminals E and F of the relay circuit of the
automatic signal-receiving device shown in Figure 2. In a similar way the circuit
of the electro-magnet B' is completed by wires from its terminals E and F to the
terminals E and F of the relay circuit of the second automatic signal receiving
device shown in Figure 3. The gas pressure regulating vessel with its sending
instrument is shown diagrammatically in Figure 4. The pressure regulating vessel
consists of an auxiliary gas holder G adapted to move up and down with variations
in the gas pressure. This gas-holder or pressure vessel G carries a contact-piece H.
which, when lifted or lowered by motion of the bell, bevond certain predetermined
limits, makes contact with one or other of two contact levers I and T. thus complet-
ing the transmitter circuit through one of the contact breakers K' or K. The
contact piece H is connected to the battery J. and through J to one end of the
primary circuit of an induction coil K. fitted with two vibrating hammers K¹
and Kadanted to give different frequencies in the secondary when the coil is
excited. When contact is made on the lower contact-piece I. the battery circuit
is completed through the make and break or interrupter K. and the primary
coil L, and when contact is made on the upper contact-piece I¹. the battery circuit
is completed through the other make and break or interrupter K2 and the primary
coil L. The terminals K and K of the secondary circuit of the induction coil are
connected to an oscillator M of the Righi type, and a reflector N is provided, so
that when the primary circuit is completed an electric discharge takes place, and
a directed induction wave issues from the oscillator in the direction necessary to
affect and operate the receiving instrument connected with the governor at the
supply station. The reflector may he of extindrical narabolic surface as shown or
have the surface of a paraboloid of revolution. When electric contact is made
through the upper contact piece I¹, waves of high frequency are sent out from the
oscillator and when electric contact is made through the lower contact-piece. I,
waves of a much lower frequency issue from the oscillator. Two separate oscillators
might be used, in place of the one, for the same purpose. Two receivers are
provided. cach of similar type, but one is tuned to respond to the waves of
higher frequency, and the other is tuned to respond to the waves of lower
frequency.
I will now describe one of these receivers. It consists of a coherer or sensitive
tube 0 of the Branly type, in which a metal powder contained in the tube separates
£

page_text: two discs 01 and 0 forming the terminals of a local circuit P. Normally the
resistance of the powder between 01 and 02 is very high, so that the local battery Q
is unable to send a current through the local circuit P, but when the electric waves
or surgings from the transmitter reach the tube O, the resistance of the circuit P
immediately falls, and a local current passes from the battery Q which then operates
an electro-magnetic relay R. The relay R works an electro-magnetic tapper S
and also energises the electro magnet B, by means of a battery T thus admitting
water to the top of the governor bell, and increasing the pressure of the gas supply.
The tapper S has a hammer S₁ which may operate either direct on the tube 0
or through a rod S2, as shown in Figure 2.
It will be seen that a mechanical tapper tapping at suitable regular intervals
might be used instead of the tapper S without departing from my invention.
Where reflectors, such as N' (shown in section in Figures 2 and 3), are used in the
receiver suitable short strips of copper 03 and 04 are connected in the circuit at
each end of the tube 0.
The electro-magnetic apparatus in the receiver is shunted by non-inductive
resistances to prevent sparking at the contacts and disturbances by the local
battery current.
Choking coils P₁ and P2 are provided in the circuit P between the coherer
and the relay R to cause the oscillating current induced by the transmitted electric
waves to pass through the coherer rather than the relay.
An exactly similar receiver to that iust described is provided (see Figure 3) to
operate the unloading valve C through its electro-magnet 13 but this receiver is
tuned to respond to the signals of different frequency from the first. Each receiver
therefore responds only to the signals from its corresponding transmitter and the
gas pressure is therefore controlled by the pressure in the district.
In many cases I find it necessary to place the transmitter, or receiver, or both, or
it may be only suitable parts of one or both, at a considerable height above the
ground. This is preferable especially where telegraph or telephone wires pass
through the intervening space between the gas supply station and the district
supplied.
Interference with telegraph and telephone circuits may be avoided by placing
the reflectors in the receiving and transmitting instruments shown in Figures 2
and 3 in such positions that their axes are horizontal or approximately horizontal,
and situated at such a distance above the ground that there is clear space between
the sending and receiving instruments.
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. Governing the pressure of gas supply to a district from a pressure controlling
device in the district by means of space telegraphy without line wires.
2. Controlling the loading of a gas governor for regulating the gas pressure at
the supply station by means of space telegraphy without line wires from the
gas pressure controlling device in the remote district, substantially as described.
3. The improved means and apparatus for automatically varying the load
and pressure of gas governors substantially as described and illustrated in the
accompanying drawings.
MARKS & CLERK,
18. Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and 25, Cross Street, Manchester, Agents.