IMPROVEMENTS IN GAS METERS
Year: 1877

page_text: LETTERS PATENT to Samuel Johnson, of Wood Green, in the County of
Middlesex, and Richard Burton, of Clerkenwell, in the same County, for the
Invention of "IMPROVEMENTS IN GAS METERS."
Sealed the 21st August 1877, and dated the 22nd February 1877.
COMPLETE SPECIFICATION filed by the said Samuel Johnson and Richard
Burton at the Office of the Commissioners of Patents on the 22nd February
1877.
SAMUEL JOHNSON, of Wood Green, in the County of Middlesex, and RICHARD
BURTON, of Clerkenwell, in the same County. "IMPROVEMENTS IN GAS METERS."
Our Invention relates to that form of gas meter known as the "wet" gas meter,
in which the correct measurement of the quantity of gas passing through the meter
depends upon the continual accurate adjustment of the level of the water contained
in the measuring chamber.
Our Invention consists of improved methods of constructing and arranging the
parts of the apparatus hy which the height or level of the water in the measuring.
chamber is adjusted, by which improved methods the meter is rendered capable of
being regulated from outside without disturbing any of its fixed parts, and greater
cheapness of construction is attained than in wet gas meters as heretofore ordinarily
constructed and used; also of a method of supplying and retaining a sufficient
quantity of water in the overflow box through which, any surplus water in the meter
passes. Within the square front of the meter (which serves as a reservoir for the
supply of water to the measuring chamber in the method well understood and
practised in the construction of wet gas meters), we arrange a vertical pipe or
chamber of any suitable shape and dimensions, but preferably circular in plan,
and we make the upper end of this vertical chamber open and rising nearly to
the top of the square front or reservoir. The lower end of the vertical chamber we
make closed, and we provide a connecting pipe which forms a communication
between the inlet gas pipe of the meter and an opening in the bottom of the
vertical chamber described, and we also make a communication between the lowest
part of the connecting pipe described and the waste water box below the square
front or reservoir.

page_text: In those forms of gas meters in which the gas passes from the inlet pipe into the
waste water box, it is advantageous to employ a connecting pipe which forms a
communication between the upper part of the waste water box and the opening in
the bottom of the vertical chamber in place of the connecting pipe herein-before
described, and its communication with the waste water box. We make the end of
the connecting pipe which forms a communication as described between the inlet
gas pipe or the waste water box (as the case may be) and the opening in the bottom
of the vertical chamber rise vertically for a short distance within the latter, and we
make a screw thread upon its outside upon which fits a piece of vertical pipe of
larger diameter, open at both ends, and having a. corresponding screw thread inside.
Over but not closing the upper end of this last mentioned piece of pipe we place
and attach firmly by means of one or more arms or bars an inverted cup of such a
size that its sides overlap the pipe to which it is attached,, leaving a space between
the inside of the cup and the outside of the pipe sufficient for the passage of gas and
water, and leaving a space between the outside of the cup and the sides of the
vertical chamber sufficient for the passage of gas and water, and sufficient also to
allow the cup to turn horizontally within the vertical chamber. We adjust the
inverted cup and fix it to the upper screwed pipe, having its lower edge a little
below the level of the upper edge of that pipe in such a position that the lower edge
of the inverted cup is completely immersed when the vertical chamber contains
water up to the level of the upper edge of the pipe, but is above the water level in
the vertical chamber when that level sinks so far below the level of the upper edge
of the pipe that a corresponding lowering of the water in the drum of the meter
would injuriously affect the accuracy of the meter. We make the inverted cup with a
catch projecting externally from its top or side, and we make an opening in the cover
of the square front or reservoir, through which opening a key or other convenient
instrument can be inserted, fitting the catch upon the inverted cup, and the latter,
together with the pipe to which it is attached, can be adjusted exactly to the
required height by screwing the pipe to which the cup is attached up or down upon
the vertical screwed pipe upon which it fits by means of the key or instrument so
inserted. The pipe to which the inverted cup is attached may be screwed into the
vertical screwed pipe instead of being screwed outside the latter; or instead of being
screwed, one pipe may be made to slide inside the other, the joint being made gas-
tight and instead of making the inverted cup with a projecting catch the sides of
the cup may be made of such a shape that the cup can be grasped and turned by a
key or other instrument fitted to it and inserted through the opening in the cover
of the square front; or the inverted cup may be made with a groove or hollow (not
being a complete perforation) in its upper surface, and may then be screwed up or
down by means of a key, turnscrew, or other instrument inserted in like manner,
and fitted into such groove or hollow. A small opening is made in the lower part
of the vertical chamber communicating directly with the drum case of the meter,
so that the water stands at the same height in both. A suitable passage or opening
is also made between the drum case and the lower part of the square front or
reservoir, as is commonly done in some gas meters. When the exact level of the
edges of the short screwed pipe and of the inverted cup attached to it has been
adjusted by means of a key, as above described, so that the level of the water in the
drum case is at the exact height for the meter to register correctly, we close the
.opening in the top of the square front through which the key is introduced by a
cover made air-tight and gas-tight, and to which a seal may then be affixed if
'desired.
The action of the apparatus is as follows:-If the level of the water falls from
evaporation or any other cause below the lower edge of the inverted cup, a bubble
of gas passes up the screwed pipes and under the edge of the inverted cup, and
thence into the upper part of the square front or reservoir, whence a corresponding
quantity of water immediately passes (by displacement) into the drum case through
the opening between the latter and the reservoir. If the level of the water rises too
high from the accidental admission of too great a quantity, or any other cause, the

page_text: surplus water passes under the edge of the inverted cup down the screwed pipes,
and so into the waste water box beneath the reservoir.
In order to supply and retain a sufficient quantity of water in the overflow box
at the bottom of the waste water box, we provide a pipe open at both ends, the
lower end of which dips into the overflow box to the lowest point to which it is
desired that the level of the water should ever fall in the latter, whilst its upper
end passes into the square front or reservoir nearly to its top and above the level of
the water. If therefore the level of the water in the waste water box falls below
the lower end of the pipe, arranged as last described, a sufficient quantity of gas
passes up into the upper part of the square front or reservoir, whence a corre-
sponding quantity of water passes by displacement through the drum case, and down
the screwed pipes into the overflow box until a sufficient quantity has so passed to
close the lower end of the pipe in the latter.
In order that our Invention may be fully understood we hereunto annex the
accompanying Drawings. Figure 1 is a longitudinal vertical section of the gas
meter through the square front; Figure 2 is a transverse vertical section; Figure 3
is a horizontal section; Figure 4 is a front view; and Figure 5, a plan of the meter.
A is the square front or reservoir containing water; B is a vertical chamber open at
its upper end, and having its lower end communicating by the pipe C with the
waste water box F, into which the gas is admitted from the inlet pipe D through
the pipe E. The vertical screwed pipe G rises from the end of the pipe C into the
chamber B, and has screwed upon its upper end the short screwed pipe H, upon
which is fixed the inverted cup I provided with a projection, upon which fits a key
introduced through the opening K at the top of the square front A, so that the pipe
H and inverted cup I can be screwed up or down until their exact position has been
adjusted. L is a small opening from the chamber B to the drum case M, in which
the measuring drum revolves in the usual way, actuating in doing so (by means of
the screw and wheel N) indicating apparatus contained in the index box O; a small
opening P allows the passage of water from the reservoir A into the drum case M.
A pipe R has its lower end dipping into the overflow box S, whilst its upper end
passes up nearly to the top of the reservoir A for the purpose of adınitting gas to
the latter from the overflow box when necessary, and so allowing a corresponding
quantity of water to pass through the drum case into the overflow box, as already
described.
In order to prevent the water from being sucked down under the edge of the
inverted cup and through the inner screwed pipes into the waste water box by an
action resembling that of a syphon, we modify our improved apparatus in the
following manner :- -We arrange within the vertical screwed pipe a small pipe open
at both ends, its upper end reaching nearly to the top of the inverted cup, and its
lower end descending into the waste water box. This arrangement is shewn in
Figure 1, where V is the small pipe inside the screwed pipe G. Or instead of this
method of construction we connect to the top or cover of the inverted cup a hollow
stem or spindle, screwed on its outside with a thread having the same pitch as that
of the vertical or screwed pipes already described.
The hollow spindle is screwed and passes vertically through a hollow pipe or
chamber which is fixed to the top of the reservoir or square front, and has its upper
and lower extremities closed with the exception of the openings through which the
hollow spindle passes. These openings we make with screw threads corresponding
and fitting gas-tight to the screw thread on the outside of the spindle. We make
the interior of the hollow pipe or chamber last described larger in transverse section
than the hollow spindle, so as to leave a space between the spindle and the walls of
the hollow pipe or chamber, within which the spindle can turn freely when screwed
round, and we make a communication between the interior of such hollow pipe or
chamber and the inlet gas pipe of the meter by means of a small pipe, which may
be placed either outside or inside the square front, as may be deemed most con-
venient. We also make an opening through the side of the spindle into its interior
in such a position as to be constantly within the hollow pipe or chamber, and in

page_text: constant communication, by means of the small pipe last described, with the inlet
gas pipe of the meter. The upper end of the hollow spindle we close and make
square, or of such other convenient shape as to fit a suitable key or instrument, by
which it can be turned round so as to raise or lower the inverted cup until the
proper position of the latter has been adjusted in a manner similar to that already
described. The hollow spindle may sometimes be made to slide gas-tight through
the openings in the extremities of the hollow pipe or chamber, instead of being
screwed through them in the manner herein-before described, and stuffing boxes
may be provided at one or both ends. We prefer to make the hollow pipe through
which the hollow spindle passes of internal diameter sufficiently large to allow the
inverted cup to be introduced and withdrawn through it when requisite.
Figure 6 shews this method of construction and arrangement; W is the hollow
spindle fixed to the top of the cup I, and screwed through the pipe or chamber X
which is fixed to the top of the reservoir A. The small pipe Y communicates
between the hollow space in the interior of the pipe or chamber X and the inlet
pipe D. Through the opening Z in the side of the hollow spindle W gas from the
inlet pipe has always free access by means of the pipe Y to the inside of the
inverted cup I.
We sometimes fix the hollow pipe or chamber through which the spindle passes
beneath the top of the square front or reservoir instead of projecting above it, as
shewn in the Drawing, and in that case we make an opening in the top of the
square front or reservoir through which the extremity of the spindle may project or
may be grasped and moved within the reservoir by means of a key or other
appropriate instrument. When the level of the inverted cup has been accurately
adjusted, so that the level of the water in the drum case is at the exact height for
the meter to register correctly, access to the extremity of the spindle may be closed
by fastening over it a cap or cover to which a seal may be attached, if desired.
By means of our Invention herein-before described, the apparatus for regulating
the level of the water can be adjusted from the outside of the meter without
disturbing any of its parts after they have been fixed; and as the adjustment can
be effected whilst the meter is being "proved," the utmost accuracy of registration
can easily be secured.
Having now described our Invention, and the manner in which it is to be
performed, we claim,-
The method of adjusting and regulating the height of the water in the drum case
of wet gas meters by means of a screwed or sliding pipe carrying an inverted cup,
and raised or lowered when required from outside the meter, substantially as
lierein-before described and shewn in the Drawings.
Also, the combination with such inverted cup actuated as described, of a pipe
admitting gas into the inverted cup, substantially as and for the purpose described.
Also, the method of supplying the overflow box of wet gas meters with water
from a reservoir by the use of a pipe admitting gas into such reservoir when
necessary, arranged substantially as herein-before described and shewn in the
Drawings.
Also, the combination of parts constituting respectively the two modifications
of our improved construction of gas meter, substantially as and for the purposes
described and shewn in the Drawings hereunto annexed.
In witness whereof, we, the said Samuel Johnson and Richard Burton, have
hereunto set our hands and seals, this Nineteenth day of February, in the
year of our Lord One thousand eight hundred and seventy-seven.