IMPROVEMENTS IN METERS FOR MEASURING LIQUIDS
Year: 1880

page_text: LETTERS PATENT to Alfred Willmer Pocock, of 15, Spencer Road, Wandsworth,
in the County of Surrey, for an Invention of "IMPROVEMENTS IN METERS FOR
MEASURING LIQUIDS."
PROVISIONAL SPECIFICATION left by the said Alfred Willmer Pocock at
the Office of the Commissioners of Patents on the 10th February 1880.
ALFRED WILLMER POCOCK, of 15, Spencer Road, Wandsworth, in the County of
Surrey. "IMPROVEMENTS IN METERS FOR MEASURING LIQUIDS.”
This Invention has more especially for its object to provide a reliable meter for
measuring water as it is delivered from water supply mains, but the meter may
also be used for measuring other liquids.
For this purpose I form the meter with expanding and collapsible chambers into
which the liquid is alternately admitted from the supply and expelled to the pipe
by which the liquid when measured is to be delivered. One side of each of such
chambers I form of a flexible diaphragm which can either move inwards and lie
against the opposite side of the chamber or can be moved outwards away from it.
The centre of each such diaphragm I connect by a connecting rod with a crank pin
on a spindle, which as the diaphragms of the chambers move in and out is revolved,
and in revolving gives motion to counting and registering apparatus, and to
mechanism for alternately admitting liquid to the chambers from the supply main,
and afterwards allowing the liquid which has entered and filled the chamber to
escape to the delivery pipe. So far the apparatus is similar to other liquid meters
heretofore constructed. My improvements relate first to a means for preventing
the pressure of the liquid as it expands the chambers from unduly distending or
bursting the flexible diaphragms.
To prevent this the outside of the central part of the flexible diaphragm has a
metal disc secured to it; to the outer circumference of this metal disc are hinged
numerous metal plates which extend radially from it and lie against the outer
surface of the diaphragm.
The outer ends of these radial plates have hinged to them other plates, preferably
shorter plates, which form links to joint them to other plates which are held fast
around the circumference of the diaphragm. The links are at an angle to the

page_text: radial plates so that they allow the outer ends of these plates to approach towards
or recede from the centre of the diaphragm as the diaphragm is moved in and out,
when consequently the radial plates alternately come parallel with the metal disc,
to which they are jointed or turn into positions at an angle to it. The flexible
diaphragm I make by preference of vulcanized india rubber. The outer edge of the
disc is turned over and the outermost plates of the jointed metal plates which cover
the exterior of the diaphragm lie between the diaphragm and its turned over edge.
These plates with the thickness of rubber above and below them are clamped up to
the outer circumference of the rigid portion of the measuring chamber.
The outer circumference of the flexible diaphragm is thus securely held and a
tight joint obtained.
In order to ensure that the central portion of the diaphragm shall move to and
fro in a straight line in and out from the rigid side of the chamber I cause a pin or
stem to project from the centre of the rigid side of the chamber and to pass through
the centre of the diaphragm and the metal disc which covers its exterior, and to
the outer side of this disc I secure a metal cap which fits to the sides of the pin or
stem and covers over its extremity. The cap sliding to and fro upon the pin keeps
the centre of the diaphragm in proper position. On the outside of the cap are
projecting pins or trunnions which are coupled by connecting links with the crank
of the crank axis of the meter.
The several measuring chambers of the meter (by preference I use three) are
placed at equal angles to one another around the crank shaft, so that the crank
shaft is at the centre of the space enclosed between the chambers, and the central
caps or covers of the flexible diaphragms of all the chambers are connected by their
connecting rods with one and the same crank.
To alternately admit liquid to and allow it to escape from the measuring chambers
I use a single slide valve. If three measuring chambers are used then this valve is
made triangular with a central triangular opening through it, and the face against
which this valve works has formed in it three ports from which passages or channels
pass to each measuring chamber, each chamber being thus in communication with
one port only. The ports are made at equal angles to one another, so forming a
triangle corresponding with the form of the valve. At the back of the triangular
valve is formed a cylinder, the extremity of which is caused to fit and work against
a flat surface which is parallel with the valve face and forms the cover to the valve
chamber. The cylinder is for this purpose made telescopic in two parts, which by
springs are pressed outwards away from one another. A tight joint is obtained by
embracing the two parts of the cylinder with a broad ring of vulcanized india
rubber or leather.
Through the centre of this cover passes the end of the crank shaft of the meter,
and a crank pin carried by it enters a hole in a plate which stands across the
interior of the cylinder at the back of the valve, so that when the crank shaft is
rotated the valve is moved in a circular course. The plate above mentioned is
perforated so as not to obstruct the flow of liquid past it.
At the same time that the valve is moved in a circular course it is also maintained
with the edges of its face always parallel with the edges of the ports in the face
against which the valve works. This I effect by jointing the valve by a pair of
links to a bar or frame which is itself by other links at right angles to the links
first mentioned jointed to pins that stand up from the valve face. Or the same
effect might be obtained by using guide surfaces at right angles to one another, but
it is better to use links as they work with less friction. Or the edges of the valve
face may be kept parallel to the edges of the ports by two or more links of the
same length as the throw of the valve crank, and which are jointed at one end to
arms extending from the valve and at the other end to the valve face, and which
links revolve similarly to the valve crank.
The liquid to be measured is admitted to a casing which surrounds the valve,
and as the valve is moved the ports in the valve face are successively uncovered

page_text: and open for liquid to pass from the casing through the port to one of the measuring
chambers. In the same way the ports are in succession uncovered and open to the
interior of the valve, so that liquid may pass into the interior of the valve from the
measuring chamber with which the uncovered port communicates. Thus the
measuring chambers are in rotation first filled with and then emptied of the liquid
to be measured. The liquid escaping from the measuring chambers into the interior
of the valve passes away through holes in the plate that the back of the valve
works against and passes into the central space enclosed by the several measuring
chambers, and may be led off at any suitable point from this space.
If desired, the flexible diaphragms of the measuring chambers might instead of
moving to and from a rigid side of one chamber be placed as a diaphragm .or
partition between two such sides; in this case the diaphragm would require to have
a set of rigid jointed plates on both its sides, instead of one only, or two flexible
diaphragms might be employed, having the set of metal plates between them.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alfred Willmer Pocock in the Great Seal Patent Office on the
10th August 1880.
ALFRED WILLMER POCOCK, of 15, Spencer Road, Wandsworth, in the County of
Surrey. "IMPROVEMENTS IN METERS FOR MEASURING LIQUIDS."
This Invention has more especially for its object to provide a reliable meter for
measuring water as it is delivered from water supply mains, but the meter may
also be used for measuring other liquids. For this purpose I form the meter with
expanding and collapsible chambers, into which the liquid is alternately admitted
from the supply and expelled to the pipe by which the liquid when measured is to
be delivered. One side of each of such chambers I form of a flexible diaphragm
which can either move inwards towards the opposite side of the chamber, or can be
moved outwards away from it. The centre of each such diaphragm I connect by
a connecting rod with a crank pin on a spindle, which as the diaphragms of the
chambers move in and out is revolved, and in revolving gives motion to counting
and registering apparatus, and to mechanism for alternately admitting liquid to the
chambers from the supply main, and afterwards allowing the liquid which has
entered and filled the chamber to escape to the delivery pipe. So far the apparatus
is similar to other liquid meters heretofore constructed. My improvements relate
first to a means for preventing the pressure of the liquid as it expands the
chambers from unduly distending or bursting the flexible diaphragms.
To prevent this, the outside of the central part of the flexible diaphragm has a
metal disc secured to it; to the outer circumference of this metal disc are hinged
numerous metal plates which extend radially from it, and lie against the outer
surface of the diaphragm.
The outer ends of these radial plates have hinged to them other plates, preferably
shorter plates, which form links to joint them to other plates which are held fast
around the circumference of the diaphragm. The links are at an angle to the
radial plates, so that they allow the outer ends of these plates to approach towards
or recede from the centre of the diaphragm as the diaphragm is moved in and out,
when consequently the radial plates alternately come parallel with the metal disc
to which they are jointed, or turn into positions at an angle to it.
The flexible diaphragm I make by preference of vulcanized india rubber; the
outer edge of the india rubber, and the outermost plates of the jointed metal plates
are clamped up to the outer circumference of the rigid portion of the measuring
chamber.
The outer circumference of the flexible diaphragm is thus securely held, and a
tight joint obtained..
In order to ensure that the central portion of the diaphragm shall move to and
fro in a straight line in and out from the rigid side of the chamber, I cause a pin or
stem to project from the centre of the rigid side of the chamber, and to pass through
the centre of the diaphragm, and the metal disc which covers its exterior, and to
the outer side of this disc I secure a metal cap which fits to the sides of the pin or
stem, and covers over its extremity. The cap sliding to and fro upon the pin keeps
the centre of the diaphragm in proper position. On the outside of the cap are
projecting pins or trunnions which are coupled by connecting links with the crank
of the crank axis of the meter.
The several measuring chambers of the meter (by preference I use three) are
placed at equal angles to one another around the crank shaft, so that the crank
shaft is at the centre of the space enclosed between the chambers, and the central
caps or covers of the flexible diaphragms of all the chambers are connected by their
connecting rods with one and the same crank.
To alternately admit liquid to and allow it to escape from the measuring

page_text: chambers, I us a single slide valve. If three measuring chambers are used, then
this valve is made triangular with a central triangular opening through it, and the
face against which this valve works has formed in it three ports, from which
passages or channels pass to each measuring chamber, each chamber being thus in
communication with one port only. The ports are made at equal angles to one
another, so forming a triangle corresponding with the form of the valve. At the
back of the triangular valve is formed a cylinder, the extremity of which is caused
to fit and work against a flat surface, which is parallel with the valve face, and
forms the cover to the valve chamber. The cylinder is for this purpose made
telescopic in two parts, which by springs are pressed outwards away from one
another. A tight joint is obtained by embracing the two parts of the cylinder with
a broad ring of vulcanized india rubber or leather.
Through the centre of this cover passes the end of the crank shaft of the meter,
and a crank pin carried by it enters a hole in a plate which stands across the
interior of the cylinder at the back of the valve, so that when the crank shaft is
rotated the valve is moved in a circular course. The plate above mentioned is
perforated so as not to obstruct the flow of liquid past it.
At the same time that the valve is moved in a circular course, it is also maintained
with the edges of its face always parallel with the edges of the ports, in the face
against which the valve works. This I effect by jointing the valve by a pair of
links to a bar or frame, which is itself by other links at right angles to the links
first mentioned jointed to pins that stand up from the valve face. Or the same
effect might be obtained by using guide surfaces at right angles to one another, but
it is better to use links, as they work with less friction.
Or the edges of the valve face may be kept parallel to the edges of the ports by
two or more links of the same length as the throw of the valve crank, and which
are jointed at one end to arms extending from the valve, and at the other end to
the valve face, and which links revolve similarly to the valve crank.
The liquid to be measured is admitted to a casing which surrounds the valve,
and as the valve is moved the ports in the valve face are successively uncovered
and open for liquid to pass from the casing through the port to one of the
measuring chambers. In the same way the ports are in succession uncovered and
open to the interior of the valve so that liquid may pass into the interior of the
valve from the measuring chamber with which the uncovered port communicates.
Thus the measuring chambers are in rotation first filled with and then emptied of
the liquid to be measured. The liquid escaping from the measuring chambers into
the interior of the valve passes away through holes in the plate that the back of
the valve works against, and passes into the central space enclosed by the several
measuring chambers, and may be led off at any suitable point from this space.
If desired the flexible diaphragms of the measuring chambers might, instead of
moving to and from a rigid side of one chamber, be placed as a diaphragm or
partition between two such sides; in this case the diaphragm would require to
have a set of rigid jointed plates on both its sides, instead of one only, or two
flexible diaphragms might be employed, having the set of metal plates between
them.
In the Drawings hereunto annexed I have shewn examples of meters constructed
in the manner above described.
Figures 1 to 10 shew various views of a meter constructed with three single
acting diaphragms.
Figure 1 is a horizontal section of the meter looking upwards; Figure 2 is a
side elevation, Figure 3 a vertical section, and Figure 4 a plan of the same;
Figure 5 shews the valve face with a section of the valve on same; Figure 6, a
plan of the valve and valve face, shewing links for keeping the sides of the valve
parallel with the edges of the ports in the valve face; Figure 7 shews an elevation
of the same, and Figure 8 a section taken at right angles to the section Figure 3;
Figures 9 and 10 shew a plan view and section of one of the diaphragms composed
of metallic plates, jointed together by metallic hinges.

page_text: A, A1, A2, shew the three diaphragms composed of hinged metal plates (in the
manner clearly shewn at Figures 9 and 10) and lined with vulcanized india rubber
as above described. The outermost plates of the jointed metallic diaphragms and
the outer circumference of the vulcanized india rubber lining are clamped and held
in the manner clearly shewn at Figures 1 and 3; B is a metal cap standing out
from the centre of each diaphragm; C, C, are fixed pins which enter these_caps,
and form guides to compel the caps to move to and fro in straight lines; D, D, are
trunnions on the exterior of the caps; E, E, are connecting rods coupling these
trunnions with the crank M of the crank shaft F. On the end of the crank shaft
is a crank G which gives motion to the valve in the manner clearly shewn at
Figure 8. The crank G also acts against an arm on the end of a small spindle H,
which passes out from the casing of the meter through a stuffing box, and gives
motion to a train of registering wheels contained in a box secured to the exterior
of the meter, as shown at Figure 3. I is the inlet of the meter, and K the
outlet.
The action of the meter is as follows:-The water service being in connection
with the inlet I, water passes from there into the valve chamber L, and thence
(when the valve is in the position shewn in the Drawings) through the port 2, into
the chamber behind the diaphragm A', which by the pressure of the water is forced
towards the centre of the meter, causing the crank M to move round in the direction
of the arrow and forcing the diaphragms A² and A into their chambers, and their
contents through the ports 3 and 1 into the interior of the valve, and thence
through the openings V in the valve box cover into the interior of the meter, and
then away through the outlet K. As the crank M moves round the ports are
successively opened to the incoming water and then to the outlet, thus putting the
diaphragm chambers successively into connection with the incoming water, which
causes a constant revolution of the crank spindle.
The incoming water in the valve chamber L is prevented from leaking into the
outlet by the ring N, which being concentric with a ring on the back of the valve O,
is pressed against the valve box cover by a spring, the joint between the two rings
being covered by a ring of india rubber, as shewn at Figures 3 and 8.
This ring of india rubber, the ring N, and the ring on the back of the valve O
may be so formed, as shown in Figure 16, that the india rubber ring may itself act
as the spring. The valve O is compelled to move with its edges parallel to the
ports 1, 2, and 3, by the arms R, R, which are pivotted to the valve face at one
end, and at the other to the ring T and the arms S, S, which are pivotted at one
end to the valve O and the other end to the ring T.
Another way, hereinbefore mentioned, of ensuring that the sides of the valve shall
keep parallel with the ports, is shewn at Figures 18 and 19. The valve receives
motion from a crank at its centre in the same way as shewn at Figures 3, 6, and 8,
and three points on the valve are connected to three small cranks of equal throw
with the crank which gives movement to the valve, the arms of these cranks
always keep parallel with the arm of the driving crank and revolve with it, and so
the valve is kept parallel with the ports.
At Figures 11, 12, 13, 14, 15, and 16 I have shewn views of a meter constructed
with two double acting diaphragins.
Figure 11 is a plan of the meter with top cover removed; Figure 12, plan of the
meter with top cover and valve box, cover removed also; Figure 13 is a horizontal
section through centre of the meter; Figure 14 is a vertical section; Figure 15 is
an elevation with one cover and diaphragm removed; Figure 16 is a vertical
section at right angles to Figure 14.
In this meter the diaphragms divide the meter into four chambers, viz.,
S, S', T, T¹.
A, A', are the two diaphragms, each made of a flexible diaphragm of jointed
metallic links with a lining of vulcanized india rubber on either side of it. Each
diaphragm at its centre carries a cap B which works over a fixed guide pin C, as
in the meter shewn at Figures 1 to 8. On the caps are pins or trunnions D, which

page_text: as the diaphragmns move in and out give a rocking motion to arms fixed on shafts X;
these shafts pass through stuffing boxes into the upper part of the meter; here
they have other arms Y connected to them, which by links Z are connected to a
crank pin on the crank shaft F, from which motion is given to the valve and to
the recording mechanism.
The action of the meter is as follows:-When the diaphragms stand in the
position shown, the water entering by the inlet I passes thence to the valve
chamber B, thence flowing through the port 2 it passes into the chamber S¹,
This move-
pushing the diaphragm E in the direction indicated by the arrow.
ment being communicated by the rocking shaft X to the connecting rod Z, the
crank is caused to revolve and to move the valve by the eccentric on the crank
shaft. By its action the valve admits the fluid from the inlet alternately to the
chambers on either side of the diaphragms, and from them passing into the interior
of the valve to the outlet. In this way a perpetual revolution of the crank shaft
is maintained, and it being ascertained how much liquid is passed at each
revolution of the crank an index is attached accordingly, and may be worked
from the crank shaft giving motion to a spindle H, as in the meter shewn at
Figures 1 to 8.
As there are four measuring chambers the valve seating has four openings in it,
as shewn at Figure 17, one leading to each chamber, and a central opening leading
to the outlet; or, if preferable, the central opening in the valve seat might be
dispensed with and the liquid pass out of the diaphragms through the valve, and
through opening in the valve box cover, the outlet being in that case in the top
part of the meter.
The valve is caused to remain parallel with the ports in the valve face in a
similar manner to the three way valve used for the 3 diaphragm meter.
Having thus described the nature of my Invention, and the manner of performing
the same, I would have it understood that I do not confine myself to the details
shewn in the Drawings annexed, but that I claim,―
First. The construction of meters for measuring liquids, substantially as herein-
before described with reference to Figures to 8, that is to say, with three or
other number of flexible diaphragms, each forming a cover to a measuring chamber,
which measuring chambers are ranged at equal angles to one another around a
central crank shaft, so that their flexible diaphragms may cause the crank shaft to
revolve as explained, and thereby give motion to a valve that controls the admission
of liquid to the measuring chambers, and its escape from the measuring chambers
into the central space enclosed between the measuring chambers, and so to the
outlet.
Second. The construction of meters for measuring liquids, substantially as herein
before described with reference to Figures 11 to 16.
Third. The construction of the flexible diaphragms of meters for measuring
liquids of rigid radial links, jointed together by metallic joints, and lined or covered
with flexible waterproof material, substantially as described.
Fourth. The construction of the valves of meters for measuring liquids, substan-
tially in the manner herein before described.
In witness whereof, I, the said Alfred Willmer Pocock, have hereunto set
my hand and seal, this Ninth day of August, in the year of our Lord One
thecond night hundred and sighter
ALFP. WILLMER POCOCK. (L.S.)