IMPROVEMENTS IN LIQUID METERS
Year: 1871

page_text: LETTERS PATENT to Alfred Willmer Pocock, of Pimlico, in the
County of Middlesex, Engineer, for the Invention of "IMPROVEMENTS
IN LIQUID METERS."
Sealed the 15th August 1871, and dated the 17th February 1871.
PROVISIONAL SPECIFICATION left by the said Alfred Willmer Pocock
at the Office of the Commissioners of Patents, with his Petition,
on the 17th February 1871.
I, ALFRED WILLMER POCOCK, of Pimlico, in the County of Mid-
dlesex, Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN LIQUID METERS," to be as follows:-
-
My improvements relate, firstly, to the employment of eccentrically
arranged valves on the crank shaft which is turned by the piston
rods of double acting cylinders, and also to a new construction of
plug or key which the reciprocating action of the pistons causes to
revolve, and also a new arrangements of ports opening into the valve
seat.

page_text: The first-mentioned part consists of one or more cupped or plain rings
upon eccentrics on the main shaft, which rings find a scating over or
against the surface or surfaces in which the ingress and egress ports
leading from and to the cylinders are situated. These rings by there
rotation cover and uncover the ports in succession to regulate the flow
of liquid through the meter.
In the second part the plug or key is composed of two discs or plates
connected and held concentrically to each other by a semi-disc also
concentric with the other two, thus holding the two outer discs apart,
thus about one half of the plug so formed is solid, while the other
portion has a space between the two outer discs. In the solid part of
the plug and on the face, which works against the valve seat a well or
cavity is made, and in the other half in the same face a perforation is
made through the face into the space between the discs. This per-
foration permits the liquid to flow from the supply into each of the
ports successively as the plug is rotated by the action of the pistons,
while the cavity permits the liquid to flow from the other ports into the
outlet or vice versa. The piston rods are connected by cranks to the
plug, and their up-and-down movements cause the plug to rotate in a
similar manner to the plug or key described in the Specification of my
previous Patent, dated November 30th, 1869, No. 3463. The valve
seat or seatings has two or more ports or openings in them; these
lead to the cylinders. In the centre is one or more openings for the
outflow.
SPECIFICATION in pursuance of the conditions of the Letters Patent, 2
filed by the said Alfred Willmer Pocock in the Great Seal Patent
Office on the 17th August 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
WILLMER POCOCK, of Pimlico, in the County of Middlesex, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventeenth day of February, in the
year of our Lord One thousand eight hundred and seventy-one, in the
thirty-fourth year of Her reign, did, for Herself, Hor heirs and successors,
give and grant unto me, the said Alfred Willmer Pocock, Her special 3

page_text: licence that I, the said Alfred Willmer Pocock, my executors, admi-
nistrators, and assigns, or such others as I, the said Alfred Willmer
Pocock, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN LIQUID METERS," upon the condition (amongst others)
that I, the said Alfred Willmer Pocock, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and scals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Alfred Willmer Pocock, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, reference being had to the Drawings
hiereunto annexed, that is to say :-
My improvements relate to the employment of eccentrically arranged
valves on the crank shaft of liquid meters which is turned by the
piston rods of double acting cylinders, and consists of one or more
cupped or plain rings upon eccentrics on the main shaft, which rings
find a scating over or against the surface or surfaces in which the
ingress and egress ports leading from and to the cylinders are situated.
These rings by their rotation or sliding motion cover and uncover the
ports in succession to regulate the flow of liquid through the meter.
The valve scat or scating has two or more ports or openings in them;
these lead to the cylinder. In the centre is one or more openings for
the outflow.
The Invention will be understood by referring to the accompanying
Drawings, in which Figure 1 is a partial section of a meter for mea-
suring water or other liquid; Figure 2, being a transverse section
through the line 2, 2; Figure 3 is a detached view of the box, in which
the ring shaped valve works against the face plate for controlling the
ingress and egress of the liquid which has to be measured. a, a', are twa
cylinders placed side by side, and in which pistons or plungers b, b', nove

page_text: up and down under the pressure of the inflowing liquid. The plungers
b, b, have rods c, c, pinned to them which are also connected to crank
arms d, d, of a shaft e on which an eccentric and a cupped shaped
ring is fitted. The shaft is arranged in a water-tight trunk or head h,
of the meter and it carries a wheel which gears into another wheel i,
the spindle of which passes through a stuffing box to the outside to
operate the index mechanism in a similar manner to that described in
a previous Specification of a Patent, No. 3463, 1869. The trunk or
head is provided with ports or passages j, j', k, k', through which the
liquid passes from the cylinders to the outlet 4, the impurities being kept
back by the strainer or perforated tube m with which the reservoir n
into which the liquid first flows is provided. The cupped ring valve g is
ground to bear against the exterior face q of the block in which the
ports or passages are formed in a liquid-tight manner; the ring y moves
in a circular path to and fro, and up and down, without turning upon its
axis and in its motion it covers and uncovers the ports in succession.
Each port in its turn becomes the inlet as well as the outlet port, as will
be understood from the following account of the action. Suppose the
water to be entering from the inlet into the reservoir m, it thence passes
to the chamber a, and passing through the port k³, which is uncovered,
to the outside, finds its way down the passage and forces against the
under side of the piston b, causing it to move upward, thus turning the
shaft e, e, and with it the eccentric. By this means the valve is caused
gradually to uncover the port j' leading to the bottom of the cylinder a',
whereby the water is admitted to play upon the bottom of the piston b',
thus causing its ascent. When the piston has arrived at the top of its
stroke the valve has moved into such a position as to entirely cover
both ports leading to the cylinder a, namely k and ', while the port
leading to the bottom of the cylinder a, viz. j is fully open, the
piston b' being just at half stroke (as the cranks are set at right angles
to one another). Thus the motion of the shaft e, e, is continued by the
piston until by the continued rotation of the eccentric the port / is
opened, admitting the liquid to the top of the cylinder a, thus causing
the descent of the piston; when the piston 6' has arrived at the top of
the cylinder the ports j and j' will be entirely covered, while the port k
will be fully open, and the rotation of the shaft will be continued by
the descent of the piston b, which is at this moment at half stroke. The
port; leading to the top of the cylinder «' will now be gradually opened
when the liquid will find its way into the top of the cylinder a' and

page_text: press upon the top of the piston b', and so cause its descent. It will be
seen that while the liquid is being admitted to the under side of the
pistons by the ports k' and , the liquid, on the top side of the cylinder
is forced away by the motion of the pistons through the ports k and j
and passes under the valve to the central opening to the outlet, this
uncovering of two ports, one from the outside of the valve and one
from the inside, going on in successive order, so long as there is a
pressure into the inlet chamber . I fit a back stop valve o in the
reservoir n against the inlet pipe to prevent the water passing through
the meter, should the supply pipe be fitted to the outlet / by error on
the part of the workman; this also prevents fraud on the part of the
consumer.
In the views before referred to I have shown the ports as of curved
form, but in Figure 4 I have shewn them of circular form, and the
cupped ring valve is differently shaped, so that the eccentric flies in
the recess from the outside, the pressure of the inflowing water against
the face p, being sufficient to keep the valve to its work, whereas in the
former case a leather washers is attached to the valve to prevent
leakage.
Figure 5 is a sectional elevation of a meter in which the valve is of a
modified form, and one of them is arranged for cach cylinder in lieu of
having only onc valve to the two cylinders. The valves g, g', in this
case are cupped shaped or recessed, and instead of moving in a circular
direction over the ports by the eccentrics fƒ, they are caused to rise
and fall only within the straps or guide pieces shown in the face views.
Figures 6 and 7: These valves g, g', cover and uncover their respective
ports in regular order, to permit of the water flowing to and from the
tops and bottoms of the cylinders, so that the plungers 6 and 6' and
their rods c, c', act upon the shaft e and consequently upon the registering
mechanism through the wheels h¹ and i, as before explained. The trunk
of the meter of this modified arrangement is in two parts transversely,
the division being above the dirt box or reservoir n in which the strainer
is fitted, the two halves being bolted together by the tie rods t, t, as seen
in Figure 8.
Of course the modified arrangement of the cupped shaped valves
necessitates a rearrangement of the passages between the reservoir and
the cylinders, and this is shown in Figures 5, 6, 7, and 8, and also in
Figure 9, which is a sectional plan through the line y, z, of Figure 6.

page_text: I have before referred more particularly to cupped shaped rings or
valves, but the valves may be plain on their surfaces, and then the ports
would be farther apart than those shown in the Drawings.
And having now described the nature of my said Invention, and in
what manner the same is to be performed, I declare that I claim,—
Firstly. The employment of cupped or plain shaped ring valves in
liquid meters when worked by eccentrics, in the manner and for the
purposes described and shown.
Secondly. I claim the arrangements of ports and passages in liquid
meters when employed in connection with a valve or valvos which are
moved by eccentrics as hercin-before described and shown.
Thirdly. I claim the modification described with reference to Figures 5,
6, 7, 8, and 9, and also the stop valve when fitted in liquid meters as
described and shown.
In witness whereof, I, the said Alfred Willmer Pocock, have here-
unto set my hand and seal, this Seventeenth day of August One
ledad no
ANA
ALF. WILLMER POCOCK. (L.S.)