Year: 1888

page_text: Date of Application, 14th Feb., 1888
Complete Specification Left, 14th Nov., 1888
Complete Specification Accepted, 14th Dec., 1888
I, JOHN CLARET, of 61 Templeton Road, West Green Road, Tottenham, in the
County of Middlesex, Engineer, do hereby declare the nature of this invention to be
as follows:-
This invention relates to improvements in that class of liquid meter known as
inferential, in which the measurement of the quantity of liquid passing through the
meter is obtained from the revolutions of a fan, paddle wheel, or turbine, set in motion
by such liquid, and the object of the invention is to increase the sensitiveness of such
meters so as to enable them to indicate small flows of liquid with more accuracy than
has heretofore been obtained in that class of. meter. For this purpose, I employ
certain arrangements whereby the pressure of the liquid in the supply pipe is
maintained at its full head, or nearly so, up to the point of discharge or delivery of
such liquid to the fan, wheel, or turbine, whatever the pressure at the outlet pipe may
be, and therefore the velocity of the liquid striking the vanes of the fan, wheel, or
turbine, is maintained more or less constant whether the volume of liquid passing
through the meter be large or small, and thereby the fan, wheel, or tnrbine is
kept in rotary motion at a speed more nearly corresponding to the quantity of liquid
passing than in meters of the ordinary construction, in which the velocity, and
therefore the energy, of the liquid striking the blades of the fan, wheel or turbine, is
not sufficient to impart thereto a speed which bears the same proportion to the
quantity of liquid passing when that quantity is small, that the speed of the fan;
wheel, or turbine, bears to the quantity passing when that quantity is large.
I effect this object by conducting the liquid to the fan, wheel, or turbine, by a pipe
or other suitable conduit having inlet orifices placed, by preference, as near as possible
to the blades of the said fan, wheel, or turbine. Means are provided whereby the
areas of these orifices can be varied in proportion to the volume of liquid passing
through the meter; and in order to effect this variation of the areas of these orifices
automatically, I employ in connection with the means for varying them, a weighted
piston, diaphragm, Hoat, or other equivalent instrument, which is acted upon by the

page_text: liquid entering the meter, in such manner as to effect the opening or closing. of the
aforesaid inlet orifices in proportion to the volume of liquid passing, thereby main-
taining the requisite speed of the liquid impinging upon the fan, wheel, or turbine,
whatever be the quantity of such liquid entering the meter.
Instead of employing orifices the areas of which are varied by devices actuated by
a piston, diaphragm, float, or other such like instrument, I may employ one or more
inlet nozzles of elastic material such as indiarubber for example. The pressure of the
liquid on the inner side or sides of such nozzle or nozzles causing the areas of such
nozzle or nozzles to vary according as a larger or smaller quantity of liquid is passing
through the meter.

page_text: Improvements in Liquid Meters.
1, JOHN CLARET, of 61 Templeton Road, West Green Road, Tottenham, in the
County of Middlesex, 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 accompanying sheet of
Drawings, and to the letters and figures marked thereon, that is to say:
This invention relates to improvements in that class of liquid meter known as
inferential in which the measurement of the quantity of liquid passing through the
meter is obtained from the revolutions of a fan, paddle wheel or turbine set in motion
by such liquid, and the object of the invention is to increase the sensitiveness of such
meters so as to enable them to indicate sumall flows of liquid with more accuracy than
has heretofore been obtained in that class of meter. For this purpose I employ
certain arrangements whereby the pressure of the liquid in the supply pipe, is
maintained at its full head, or nearly so, up to the point of discharge or delivery of
such liquid to the fan, wheel or turbine whatever the pressure at the outlet pipe
may be, and therefore the velocity of the liquid striking the vanes of the fan,
paddle wheel or turbine is maintained more or less constant whether the volume of
liquid passing through the meter be large or small, and thereby the fan, wheel or
turbine is kept in rotary motion at a speed more nearly corresponding to the
quantity of liquid passing than in meters of the ordinary construction in which,
the velocity and therefore the energy of the liquid striking the blades of the fan,
wheel or turbine is not sufficient to impart thereto a speed which bears the same
proportion to the quantity of liquid passing when that quantity is small, that the
speed of the fan, wheel or turbine bears to the quantity passing, when that quantity
is large.
I effect this object by conducting the liquid to the fan, wheel or turbine, by a
pipe or other suitable conduit having inlet orifices placed by preference as near as
possible to the blades of the said fan, wheel or turbine. Means are provided
whereby the areas of these orifices can be varied in proportion to the volume of
liquid passing through the meter; and in order to effect this variation of the areas
of these orifices automatically employ a weighted piston, or other equivalent
instrument which is acted upon by the liquid entering the meter in such manner as to
effect the opening or closing of the aforesaid inlet orifices in proportion to the volume
of liquid passing, thereby maintaining the requisite speed of the liquid impinging
upon the fan, wheel or turbine whatever be the quantity of such liquid passing through
the meter.
Instead of employing orifices the areas of which are varied by devices actuated
by a piston, or other such like instrument, I may employ one or more inlet
nozzles of elastic material such as indiarubber, for example. The pressure of the
liquid on the inner sides of such nozzles causing the areas of their openings to
vary according as a larger or smaller quantity of liquid is passing through the
meter.

page_text: And in order that my said invention may be clearly understood
to describe the same by the aid of the accompanying drawings:
will now proceed
Figure 1 is a longitudinal sectional elevation of an inferential meter constructed
in accordance with my invention, and Figure 2 is a horizontal section of same
taken on line X X of Figure 1.
A is the body of the meter, B the inlet passage. C the outlet passage, D the
measuring turbine or wheel the spindle E of which passes upwards through the
bottom of the chamber G and is connected by worm gearing or otherwise, in
the usual way, to the registering mechanism contained therein. H is a partition in
the body. A of the meter, separating the inlet passage B from the outlet passage C.
I is a pipe or tube secured in the partition FL. The upper end of this pipe is closed,
and passes up into the interior of the turbine or wheel D and is furnished with lateral
inlet openings or ports K which, as shown in the Figures, are thus brought very near
the vanes of the turbine or wheel D. L is a hollow piston or plunger fitted to slide
easily up and down in the pipe I, it is closed at its upper end, but is furnished with
lateral ports or passages M, corresponding in number and position with the ports or
passages K in the pipe I. The piston or plunger L carries a weight which
tends constantly to keep the said piston or plunger down in the position shown in
Figure 1.
It will now be understood that any liquid passing through the meter enters the
chamber A by the passage B, and passing up the interior of the hollow piston or
plunger Lexerts a pressure upon the closed upper end thereof which causes the said
piston to rise in opposition to the action of the weight N. This causes the ports M to
open more or less to the ports K and to allow the liquid to pass through them and to
impinge upon the vanes of the turbine D so as to set it in rotary motion; and then
after escaping at the circumference of the said turbine the said liquid passes away
through the outlet. passage C. The greater the quantity of liquid entering at B the
higher the piston L is raised, and consequently the larger the area of the passage
ways through the ports M. in the piston Land the ports in the pipe I becomes, until
the said ports MK are fully open. On the other hand if the quantity of liquid
passing decreases, the weight N acts to draw down the piston L so as to decrease the
area of the passage way through the ports M and K. Thus the area of the inlet ports
or orifices MK is varied automatically in proportion to the volume or quantity of
liquid passing thereby maintaining the requisite speed of the liquid impinging upon
the wheel whatever be the quantity of such liquid passing.
The piston L is prevented from turning in the pipe I by means of a feather P
taking into a groove or slot in the pipe I, whereby the lateral coincidence of the
ports M with the ports K is preserved.
Figure 3 shows a slightly modified arrangement of the regulating piston, similar
letters of reference relating to like parts in Figures 1, 2 and 3. In this case the
piston L is connected to the weight N by the rod Land instead of being hollow is
solid. When it is raised by the pressure of the in-coming liquid its lower edge opens
the ports K in proportion to the volume of liquid passing and when lowered by the
weight N on a reduction of the volume passing, it closes the said ports, and when no
liquid is passing it rests on the flange or stop 11
It will be seen that the piston I. in Figures 1, 2 and 3 acts the part of a slide
valve to vary the area of the passage ways through the inlet ports or orifices and
it is obvious that a similar effect can be obtained if the piston L in Figure 3 be
converted into a lift valve with a seating I' The inlet port in this case consists
of the annular opening between the lift valve and its seat, and the regulation of
the area of that opening is effected by the movement of the said valve to or from
its seat by the action of the liquid on the weighted valve in the same way as on the
piston I in Figures 2 and 3.
Figure 4 is a horizontal section of a meter in which inlet nozzles of elastic
material are employed instead of a pipe with ports or orifices the areas of which
are varied by the movement of a piston or valve as described in reference to
Figures 1 to 3.
"

page_text: A is the body of the meter as before, B the inlet, the outlet passage, D the
registering fan, contained in an inner casing Q. Rare the nozzles formed of elastic
materials, such as indiarubber for example, with lips R' similar to the well known
Prideaux valve. These nozzles are held in place in apertures in the inner casing Q
by means of screwed rings S and are directed more or less tangentially to the
circumference of the fan or paddle wheel D. The liquid entering at B passes into
the annular chamber A¹ between the body A and inner casing Q, then through
the nozzles R, impinges on the vanes or blades of the fan D and then escapes
by suitable passages to the outlet C, the pressure of the liquid on the inner sides
of the elastic lips R of the nozzles R causing the areas of the openings of such
lips to vary according as a larger or smaller volume of liquid is passing through
the meter.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
First. In liquid meters, regulating the velocity of flow of liquid to the measuring fan,
paddle wheel or turbine by varying the area of the inlet orifices, ports or passages
automatically in proportion to the quantity of liquid passing through the meter,
substantially as herein before described, and illustrated in Figures 1, 2 and 3 of the
Drawings hereto annexed, and for the purpose specified.
Second. In liquid meters, the tube I with inlet orifices or parts K, the weighted
piston or valve L and the turbine, fan or wheel D, arranged, combined, and
operating, substantially as herein before described, and illustrated in Figures 1, 2 and 3
of the Drawings hereto annexed, and for the purpose specified.
Dated this 14th day of November 1888