Improvements in Apparatus for Measuring the Flow of Liquids.
Year: 1894

page_text: Date of Application, 6th Jan., 1894
Complete Specification Left, 5th Nov., 1894-Accepted, 22nd Dec.. 1894
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Measuring the Flow of Liquids.
I, WALTER BROWN HARVEY DRAYSON, of 2 Newgate Street, in the City of
London, Sanitary Engineer, do hereby declare the nature of the said invention to
be as follows:-
It is well known that in rotatory or inferential meters, water passes through
without being registered when the velocity of such water is not sufficient to set
the fan or other measuring instrument in motion, but in one arrangement of
such meters, special means are provided for measuring the quantity of liquid that
would, under the above-mentioned circumstances, pass through a meter without
registration. That arrangement consists in combining, with the main rotatory or
inferential meter, a secondary meter placed in a bye-pass and capable of measuring
small flows that would not be measured by the larger main meter. One part of
my present invention relates to an improvement in the above-mentioned arrange-
ment of a secondary meter in a bye-pass and consists in constructing the secondary
meter and the requisite valve or valves in the casing of the main meter, the
necessary passages and fan chamber being formed in the said casing instead of
making the secondary meter as a separate instrument and placing it in a bye-pass
pipe between the inlet and outlet of the main meter as heretofore. By these means
I reduce the cost of construction of such compound meters and make them more
compact than heretofore.
Another part of my present improvements relates to means whereby the above-
mentioned secondary meter may be dispensed with and the main or large meter be
made to register the small flows which, under ordinary circumstances, it would not
do. For this purpose I provide in the inlet passage of the large meter a suitable
automatically acting controlling valve (or two or more such valves may be employed
if preferred) such that when the difference of pressure between the inlet and outlet
falls to a certain point, the said valve in the main inlet closes and prevents any
more liquid from passing through the main inlet to the large meter, but any small
quantity of liquid that is required to pass after the said valve in the main inlet is
closed, and which would not be measured if it passed to the large meter in the
ordinary way, I take from the inlet passage behind the aforesaid valve and lead it
by a separate passage also provided if necessary with a similar valve to a special
inlet port in the fan casing of the large meter, the said port being so shaped and
placed that the entering liquid is directed with such velocity against the pallets of
the measuring fan of the large meter that such fan is set in motion and registers
the smaller flow. When the difference of pressure between the inlet and outlet
increases to o certain point, the aforesaid valve in the main inlet opens and allows
the liquid to flow direct to the fan chamber of the large meter, and the valve in
the inlet to the special port is closed, the larger flow being then accurately
measured.
Dated this 5th day of January 1894.
W. B. H. DRAYSON,
Per W. H. Beck,
115, Cannon Street, London, Agent.

page_text: I, WALTER BROWN HARVEY DRAYSON, of 2 Newgate Street, in the City of
London, Sanitary 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, reference being had to the accom-
panying two sheets of drawings, and to the letters and figures marked thereon, that
is to say:
It is well known that in rotatory or inferential meters water passes through
without being registered when the velocity of such water is not sufficient to set the
fan or other measuring instrument in motion, but in one arrangement of such
meters special means are provided for measuring the quantity of liquid that would,
under the above mentioned circumstances, pass through a meter without registration.
That arrangement consists in combining with the main rotatory or inferential
meter a secondary meter, placed in a bye-pass and capable of measuring small
flows that would not be measured by the larger main meter. One part of my
present invention relates to an improvement in the abovementioned arrangement
of a secondary meter in a bye-pass and consists in constructing the secondary meter
and the requisite valve or valves in the casing of the main meter, the necessary
passages and fan chamber being formed in the said casing instead of making the
secondary meter as a separate instrument and placing it in a bye-pass pipe between
the inlet and outlet of the main meter.
This part of the invention is illustrated in Figures 1, 2, 3, 4, 5 and 6 of the
accompanying drawings in which Figure 1 is a horizontal section of a meter
having this part of the invention applied thereto, Figure 2 is a plan of same,
Figure is a sectional elevation taken on line 2-2 of Figure 1; Figure 4 is a
sectional elevation taken on line 3-3 of Figure 1; and Figures 5 and 6 are
sectional elevations showing modifications of the part illustrated in Figure 4.
The
A is the general casing containing both the main meter B and the secondary
meter C. D is the general inlet passage to both meters preferably provided, as
usual, with a strainer E. F is the general outlet passage from both meters.
main meter B receives liquid from the general inlet D through the passage D¹ and
the secondary meter C from the general inlet D through the passage D. G is a
weighted valve resting upon its seating G and interposed between the passage H
from the main meter and the general outlet passage F. I is a valve adapted to
rise and close the orifice J in the valve seat K when pressed upwards with sufficient
force. This valve I is interposed between the outlet passage L from the secondary
meter C and a passage M leading from the cage N surrounding the orifice J, to
the general outlet passage F.
If the outlet at F be closed, of course both meters B and C remain stationary,
and the valves G and I remain in the positions shown in Figures 3 and 4 respectively,
the pressure in all parts of the apparatus being equal. If now the outlet F be
opened slightly to allow a small quantity of liquid to pass, but not enough to set
the measuring instrument B' of the main meter B in motion, the liquid will enter
the secondary meter C through the passage D³, will set the measuring instrument C¹
of that meter in motion, will then pass through the passage L, up past the valve I,
through the orifice J, passage M and general outlet F. The weighted
valve G remains closed and no liquid passes through the main meter until the
outlet F is opened more fully so as to reduce the pressure acting on the upper side
of the said valve G. Assuming then that the outlet F is further opened, the
quantity and velocity of the liquid passing through the secondary meter C will be

page_text: increased; and when such quantity and velocity have reached a certain point the
liquid flowing from the passage Ĺ to the orifice J carries the valve I up with it
and presses it against and closes the orifice J so that no more liquid can pass
through the secondary meter C. But by the time the quantity and velocity of the
liquid passing through the secondary meter have become sufficient to close the
valve I they have become sufficient to raise the valve G, and as soon as that is
accomplished the main meter B is set in motion, and all the liquid passing through
and escaping at the outlet F will be registered by it so long as the quantity is as
much as or more than sufficient to hold the valve I against the orifice J.
When
that quantity decreases below what is necessary to hold up the valve I and
therefore below what the main meter would register correctly, the valve I falls,
reopening the orifice J, and the valve G falls, closing communication between the
main meter B and the outlet F, and so long as the quantity of liquid passing
remains below what is required to raise the valve I to its seat, it will pass through
and be registered by the secondary meter C.
It will be obvious that the weight of the valve G, and the weight of the valve I
and the size of the latter in relation to the area of the chamber 1' in which it
works should be, by preference, so adjusted that the pressure and velocity of liquid
that will raise the valve I to its seat will be sufficient to raise the valve G from its
seat, and that that pressure and velocity shall correspond, as nearly as may be,
with that at and below which the main meter ceases to register with sufficient
accuracy.
Figure 5 illustrates a somewhat different arrangement of the valve shown in
Figure 4. L is the passage leading from the secondary meter, M the passage
leading from the valve to the general outlet passage F, I the valve and J the
orifice. In this case the valve I is hinged and hangs pendant in front of the
orifice J so long as the quantity and velocity of liquid passing does not exceed a
certain amount the liquid finds its way round the valve to the orifice J without
closing the valve, but as soon as the quantity and velocity exceeds that amount it
presses the valve I against the end of the orifice J and closes it.
Figure 6 shows another modification of the. valve. I, J, L, M and N indicate
parts corresponding to those in Figure 4 marked with similar letters.
In this case
the valve 1 is formed as the plug of a well known waste preventer; I' being the
socket in which the plug I works and which socket is suspended from the cage N by
pillars 13. When the outlet F has been opened to such an extent that the quantity
and velocity of the liquid passing through the secondary meter have reached a
certain point, the plug I rises in its socket 12 and its upper end closes the orifice J
in the same way as the valve 1 closes the orifice J in Figure 4.
By the means above described I reduce the cost of construction of such compound
meters, and make them more compact than heretofore.
Another part of my present improvements relates to means whereby the above-
mentioned secondary meter may be dispensed with, and the main or large meter
be made to register the small flows which under ordinary circumstances it would
not do.
This part of the invention is illustrated in Figure 7 of the drawings which is a
horizontal section of a meter having this part of the invention applied thereto.
In this case the inlet passage D' of the meter is furnished with one or more
automatically-acting controlling valves G which may be arranged and constructed
in a manner similar to the valve G in Figure 3. This valve G is weighted,
o that when the difference of pressure between the inlet D and outlet F falls
to a certain point, the said valve closes and prevents any more liquid from
passing through the main inlet D₁ to the meter; but any small quantity of liquid
that is required to pass after the said valve G is closed, and which would not
be measured if it passed to the meter in the ordinary way, is taken from the
inlet passage D behind the aforesaid valve G and is led by a separate passage D'
through the orifice J in the valve seat K, and the passages D³ to a special
supplementary inlet port Q in the fan casing R of the meter, the said port Q being

page_text: so shaped and placed that the entering liquid is directe.l with such an increased
velocity against the pallets S of the measuring fan of the meter that such fan is
set in motion and registers the smaller flow. When the difference of pressure
between the inlet D and outlet F increases to a certain point, a controlling valve
similar to the valve I shown in Figure 4 for example is closed against the lower
end of the orifice J and prevents the further passage of liquid to the port Q and
the aforesaid valve G is raised and allows the liquid to flow direct to the fan
chamber T of the meter through the usual ports U U.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
First. In a compound liquid meter of the kind hereinbefore referred to,
constructing the secondary meter with its passages and fan chamber in the same
casing as the main meter, substantially as described.
Second. Constructing compound liquid meters of the kind hereinbefore referred
to with their main and secondary meters and their respective controlling valves
within one casing, substantially as described.
Third. In a liquid meter the use of a supplementary inlet port in the fan casing,
so shaped and placed that a comparatively small quantity of liquid entering
through it and impinging upon the pallets of the measuring fan at a greater
velocity than that at which the same quantity of liquid would enter the meter
through the ordinary inlet ports, imparts motion to the said fan and enables it to
register the passage of smaller quantities of liquid than it otherwise would do,
substantially as described with reference to Figure 7 of the drawings and for the
purpose specified.
Fourth. In a liquid meter the main inlet to which is governed or controlled by
a weighted valve the use of a supplementary inlet port opening into the fan
chamber and supplied with liquid from the main inlet of the meter behind the said
governing or controlling valve, and a controlling valve located in the passage
leading to the said port, substantially as described with reference to Figure 7 of the
drawings, and for the purpose specified.
HV A
WALCI TIK NA OVAL NYAVEmner LAYA
W. B. H. DRAYSON,
Per W. H. Beck,
115, Cannon Street, London, Agent.