Improvements in Apparatus for Measuring the Flow of Liquids.
Year: 1889

page_text: Date of Application, 3rd Oct., 1889
Complete Specification Left, 3rd July, 1890-Accepted, 9th Aug., 1890
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Measuring the Flow of Liquids.
I, JOSEPH JOHN TYLOR, of 2 Newgate Street in the City of London, Civil Engineer,
do hereby declare the nature of the said invention to be as follows :-
--
It is well known that in rotary 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. The object of my present
invention is to provide means for measuring the quantity of liquid that would, under
ordinary circumstances, pass through such a meter without registration. For this
purpose I combine with the main rotary or inferential meter a secondary piston
or other positive meter, or a secondary smaller rotary or inferential meter capable
of measuring minimum flows, in such manner that so long as the velocity of the
liquid passing through the main rotary or inferential meter is sufficient to set
the fan or other measuring instrument thereof in motion, the registration of the
quantity passing is effected by one or both of the measuring instruments; but
when the velocity of the liquid is not sufficient to set the measuring instrument
of the main meter in motion, the liquid is caused to pass through the secondary
piston or other meter whereby its quantity is measured; and the sum of the readings
of the two meters represents the total quantity of liquid passed. When the velocity of
the liquid becomes again sufficient to set the main rotary or inferential meter in motion,
the secondary meter may cease to act.
In order to put the secondary meter into and out of action at the proper times
automatically, I employ a more or less balanced valve controlling the inlet to the
Dain meter and applied in such manner that when the difference of pressure
between the inlet and outlet of the main meter falls to a certain point the valve
will close and prevent any more liquid from passing through the main meter, but will
cause any small quantity of liquid that would not be measured by the main meter,
were it to pass through the same, to pass instead through the secondary meter from
which it is conducted to the outlet side of the main meter without passing through
the latter at all.
By these means I am enabled to measure small flows of liquid, that would other-
wise pass through a large inferential meter unmeasured, without restricting to any
considerable extent the larger flow, as for example in the case of a large inferential
meter on a fire main where at times a full bore flow is required, which is properly
registered by such meter, whilst at other times only a comparatively small flow
passes through the main which the large meter does not register at all.
Dated this 1st day of October 1889.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Measuring the Flow of Liquids.
I, JOSEPH JOHN TYLOR of 2 Newgate Street, in the City of London, Civil Engineer,
do hereby declare the nature of the said 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 accompanying two sheets of drawings and to the
letters and Figures marked thereon that is to say :-
It is well known that in rotary or inferential meters water passes through
without being registered when the velocity of such water is not sufficient to set

page_text: '
the fan or other measuring instrument in motion. The object of my present invention
is to provide means for measuring the quantity of liquid that would, under ordinary
circumstances, pass through such a meter without registration. For this purpose I
combine with the main rotary or inferential meter a secondary piston or other positive
meter or a secondary smaller rotary or inferential meter capable of measuring
minimum flows, in such manner that so long as the velocity of the liquid passing
through the main rotary or inferential meter is sufficient to set the fan or other
measuring instrument thereof in motion, the registration of the quantity passing is
effected by that measuring instrument, or by that and the measuring instrument of
the secondary meter conjointly but when the velocity of the liquid is not sufficient
to set the measuring instrument of the main meter in motion, the liquid is
prevented from passing through the measuring chamber of the main meter; but
is caused to pass instead through the secondary piston or other meter whereby
its quantity is measured; and the sum of the readings of the two meters
represents the total quantity of liquid passed. When the velocity of the liquid
becomes again sufficient to set the main rotary or inferential meter in motion, the
secondary meter may either cease to act, or continue to act as well as the main
meter according as the pressures of liquid at its inlet and outlet are the same
or differ.
:
In order to put the meter into and out of action at the proper times automatically
I employ a valve controlling the inlet thereto applied in such manner that when the
difference of pressure between the inlet and outlet falls to a certain point, the valve
will close and prevent any more liquid from passing through the main meter, and
any small quantity of liquid that would not be measured by the main meter, were it to
pass through the same, then passes instead through the secondary moter from which it
is conducted to the outlet side of the main meter without passing through the
measuring chamber of the latter.
Figure 1 of the drawings hereto annexed represents a plan view of apparatus
constructed in accordance with my invention.
Figure 2 is an elevation, partly in section on the line X X of Figure 1.
Figure 3 a sectional elevation on line Y Y of Figures 1 and 2, and
Figure 4 a partial section on line X X Figure 1 to a larger scale than that shown in
Figure 2.
A represents the main rotary or inferential meter, which may be of any ordinary
construction. Bis the secondary meter above referred to, shown in the drawing as
an ordinary positive or piston meter, but it may, if preferred, consist of a smaller
rotary or inferential meter. But whether it be a positive or a rotary meter this
secondary meter should be one capable of measuring comparatively small flows of
liquid. is a valve box placed in the inlet pipe leading to the main meter A. Dis
the inlet passage to this valve box, E a strainer, F a box to receive the dirt or foreign
substances retained by the strainer, G a valve which closes on to the seating H.
I is a cylindrical chamber closed at top, formed above and concentric with the
valve G. K is a piston, capable of moving up and down liquid tight in the cylinder I
and is somewhat larger in area than the passage through the valve seat H. The
stem G of the valve G passes into and is guided by a hole formed in the pro-
jection depending from the piston K which latter rests upon the top of the
stem G so that its weight and the pressure on the upper side thereof tend to force
the valve G to its seat H. L is the outlet from the valve box leading to the
inlet of the main meter A. A passage N leads from the space above the
piston K to the outlet passage A' of the main meter A. A passage O (Figure 3)
leads from the box F or from some other part of the main supply pipe to the inlet
passage of the secondary meter B, a passage P leading from the outlet passage of
such meter to the space above the piston K. It will be seen that the secondary
meter is placed in a bye-pass passage between the main supply pipe and the outlet.
passage from the main meter.
The action of the apparatus is as follows:-
Lu Figure 2 the valve G is shown closed against its seat being urged thereto by

page_text: its own weight as well as by that of the piston K which rests on it, and also by the
liquid pressure above the said piston. If the outlet from the main meter A be closed,
of course both meters remain stationary and the valve and piston remain in the
position shown in Figure 2. the pressure of liquid in all parts of the apparatus being
equal. If now the outlet A from the main meter A be opened slightly to allow a
small quantity of liquid to pass, but not enough to set the measuring instrument of
the main meter A in motion, the pressure in the outlet A' of the meter A will be
somewhat reduced, and liquid will How from the main through the passage D, box F,
passage O, secondary meter.B, passage P, space 1, passage N and outlet passage
of meter A, to its intended destination, without passing through the measuring
chamber of the meter A. The reduction of pressure in the outlet A' causes a
reduction of pressure in the space and consequently a reduction of pressure on
the piston K and therefore on the valve G, but, inasmuch as the area of the
piston K. is greater than that of the valve G, the latter is kept closed against the
pressure in the main and the inlet D until the outlet A' is opened sufficiently to
reduce the pressure in the space I' to a point at which the downward pressure on
the piston K is no longer sufficient to balance the pressure from the main supply
pipe, and the valve G then opens to its full extent, allowing the full discharge to take
place through the measuring chamber of the main meter and to be thereby measured.
The flow through the meter B, chamber I', and passage N continues as well as that
through the main meter unless the difference of pressure in the chamber and that
at the inlet to the meter B should from any cause become too small to work such
meter, in which case the flow through the secondary meter ceases When the How
through the main meter is again reduced to, or below the quantity necessary fo
keep the main meter in motion, the pressure accumulates in the space over the
piston K. until the pressure on the latter is sufficient to close the valve G against
the pressure in the main supply pipe, thereby cutting off the supply to the main
meter while the small quantity still flowing passes through and is measured by the
secondary meter B, as before explained.
The resistance in the secondary meter has to be adapted to suit each particular
case, and depends upon the sensitiveness of the main meter A, that is to say, upon
the quantity of water that has to pass through it under ordinary circumstances before.
its measuring fan will be put in motion.
The difference between the area of the piston K and of the valve G must be
such that the pressure in the chamber exerted on the said piston will keep the
valve G closed, until the resistance at the outlet A' of the main meter is.
reduced sufficiently to allow enough liquid to pass to set the main meter A in
motion.
The action of the apparatus may be regulated within certain limits by varying the
resistance in the passage Nor P, whereby the opening of the valve. G may be-
accelerated or retarded as required.
As above stated the secondary meter instead of being of the positive or piston kind
may be of the rotary or inferential kind. Figure 5 of the drawings shows the
application of such a meter to the apparatus described in reference to Figures 1 to 4
in place of the positive meter B therein shown, similar letters of reference relate to.
like parts in all the Figures 1 to 5.
When the secondary meter is of the rotary or inferential kind as above described,
it is important that it should be constructed so as to measure as accurately as possible.
small flows of liquid and for the purpose of registering these small flows, I prefer to
employ the construction of meter shown in Figures 6 and 7 which is applicable to
general purposes as well as when combined with another meter. Figure 6 is a plan
and Figure 7 a longitudinal section.
This meter is preferably made with an inner casing Q containing the working
parts, and an outer casing R the inlet passage S being separated from the outlet
passage T by means of a bevil joint U in a manner similar to that described in the
specification of a patent granted to me bearing date the 3rd September 1885,
No. 10443. The inner casing Q is secured in the outer casing R by the glass cover

page_text: which bears on its upper edge. The joint between the said glass cover V and the
outer casing R being made liquid tight by the jointing material W. The glass cover V
is held in place by the metallic ring Z and bolts Z. The clockwork or registering
mechanism is contained in the case a which is dropped into the upper part of the
inner casing Q, and the spindle 6 of the registering fan passes up through a hole in
the casing whereby the friction of the ordinary stuffing box is avoided. In this
arrangement the registering mechanism works in the water under pressure and the
wheels may be made of vulcanite. c is a special form of brake which, acting in con-
junction with the corrugations formed in the measuring chamber and described in the
Specification of a Patent granted to me bearing date the 27 October 1887 and No. 14652,
enables a large range of sufficiently accurate registration to be obtained. The brake c
is provided on its under side with ribs c¹ and has a trumpet mouth opening dat its centre,
through which the liquid has to pass before reaching the outlet passage T.
By means of the apparatus above described, I am enabled to measure small flows
of liquid that would otherwise pass through a large rotary or inferential meter
unmeasured, without restricting to any considerable extent the larger flow; as for
example, in the case of a large inferential meter on a fire-main where, at times, a full
hore flow is required, which is properly registered by such meter whilst at other
times, only a comparatively small flow passes through the main supply pipe which the
large meter would not register at all.
Having now particularly described and ascertained the nature of my said
invention, and inhat manner the same is to be performed, I declare that what I
claim is
First. The combination with a main rotary or inferential meter, of a secondary
meter arranged and adapted to measure comparatively small quantities of liquid
which not being sufficient to set in motion the measuring instrument of the main
meter would otherwise pass through such meter without being registered, substantially
as hereinbefore described, and illustrated in Figures 1 to 5 of the drawings hereto
annexed.
Second. The combination with a main rotary or inferential meter of a valve and
piston so arranged and adapted, that the said valve is opened when the difference of
the pressures in the outlet of the main meter and in the main supply pipe, increases
beyond. a certain point, and is closed when such difference of pressure decreases to or.
below such point, and a secondary meter placed in a bye-pass passage between the
main supply pipe and the outlet passage of the main meter, substantially as herein-
before described, and illustrated in Figures 1 to 5 of the drawings.
Third. The secondary rotary or inferential meter constructed as hereinbefore
described, and illustrated in Figure 6 and 7 of the drawings.
Dated this 3rd day of July 1890.
Dated this 3rd day of July 1890.
J. J. TYLOR.
Per W. H. Beck,
115, Cannon Street, London, E.C., Agent.
J. J. TYLOR.
Per W. H. Beck,
115, Cannon Street, London, E.C., Agent.