IMPROVEMENTS IN FLUID METERS
Year: 1861

page_text: LETTERS PATENT to William Dingwall, of Dundee, in the County of
Forfar, North Britain, Joiner, for the Invention of "IMPROVEMENTS IN
FLUID METERS."
Sealed the 17th December 1861, and dated the 1st July 1861.
PROVISIONAL SPECIFICATION left by the said William Dingwall at the
Office of the Commissioners of Patents, with his .Petition, on the 1st
July 1861.
I, WILLIAM DINGWALL, of Dundee, in the County of Forfar, North
Britain, Joiner, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN FLUID METERS," to be as follows, that is to say:-
This Invention relates to improvements in the construction of meters for
measuring water or other fluid. In a meter embodying one modification of
the improvements, the details are contained in a chamber of a shape resem-
bling that obtained by placing two truncated cones with their bases together,
and the measuring is effected by means of a compound diaphragm working to
and fro in the chamber. The diaphragm consists of a central metal portion
attached to an annular portion of a flexible material such as leather, the outer
edge of which last is fixed in a joint running round the chamber at the
junction of the two cones. The valves which regulate the passage of the
fluid alternately to and from the opposite sides of the diaphragm are arranged
in the central metal part thereof. The central metal part of the diaphragm

page_text: is formed with two internal chambers, which communicate respectively with
the inlet and outlet pipes by means of flexible tubes arranged so as to accom-
modate themselves to the movements of the diaphragm. Each internal
chamber has two openings, one through the top and the other through the
bottom of the diaphragm, and directly opposite to the former; each pair of
openings is controlled by a single disc valve lying between them, the moving
up or down of which closes the top or bottom opening. The distance between
the opposite ports or apertures (of either the inlet or outlet chamber) is
exceedingly short, being only equal to the thickness of the valve, and the slight
space necessary for the passage of the fluid through one of the openings; and
in consequence of this arrangement, not only is the effective discharge area
always the same (one aperture being opened precisely as the opposite one is
being closed), but there is no appreciable column of fluid between the ports,
the motion of which has to be reversed. The two valves are fixed upon
spindles jointed to a beam or lever centred midway between them on a small
bracket on the diaphragm in such a way that the two valves are always in
opposite positions. To one end of the beam there is jointed a peculiarly-shaped
lever, and to the other end a link, which is connected to the lever by a slotted
link, a pin on the lever working in the slot of the link, whilst a spring is
applied to the lever pin and slotted link in such a way as to cause a tension
between the lever pin and the end of the slotted link jointed to the beam
link. The action of this arrangement is to keep the valves firmly against
their seats, except at the instant they have to change their positions. The
change of the valves is effected by a movement of the peculiarly-shaped lever
brought about as the diaphragm reaches either end of its stroke by the
tightening of a check strap, or by a stop which can be accurately adjusted to
make the meter measure a determinate quantity at each stroke. The move-
ment of the lever causes its pin to approach the end of the valve beam which
is centre to the short link, and whilst this takes place the valves are held in
their unchanged position with increased firmness; but as the movement con-
tinues, the lever pin passes the centre of the link, whereupon from the position
of the parts the tendency of the spring is to throw the links over, and, at the
same time to reverse the valves, and press them firmly against their opposite
seats. Counting mechanism of the ordinary kind is applied to register the
number of double strokes made by the diaphragm, the first ratchet wheel of
which mechanism is acted upon by a catch carried by a lever moved by the
diaphragm each time it reaches that end of its stroke. A safety valve is
in some cases applied to the outlet chamber of the diaphragm to provide
against injury from back pressure; this valve is double,. and consists of two.

page_text: washers applied to the outsides of apertures on opposite sides of the diaphragm,
being fixed on a single spindle passing across. The washers are of an elastic
or flexible material, and they can be screwed up more or less tightly. When
the back pressure is sufficiently great to lift the washers, the fluid can pass
directly through the diaphragm, and so be incapable of doing injury.
The details of the meter may be considerably modified without departing
from the principal features of improvement; thus a piston or other moving
partition may be substituted for the flexible or partially flexible diaphragm,
or a different form of chamber may be used. In some cases the peculiarly-
shaped lever herein-before mentioned may be dispensed with, and a spring
may be applied to act tensionally between one end of the beam and the outer
end of the link at the other end of the beam, stops being provided to limit the
motion of the link in opposite directions, whilst the check or stop which limits
the stroke of the diaphragm, and causes the reversal of the valves, is arranged
to act directly upon the link.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Dingwall in the Great Seal Patent Office on the
28th December 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
DINGWALL, of Dundee, in the County of Forfar, North Britain, Joiner,. send.
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters:
Patent, bearing date the First day of July, in the year of our Lord One
thousand eight hundred and sixty-one, in the twenty-fifth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Dingwall, Her special licence that I, the said William Dingwall, my
executors, administrators, and assigns, or such other as I, the said William
Dingwall, 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.
FLUID METERS," upon the condition (amongst others) that I, the said William
Dingwall, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same

page_text: 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 William Dingwall, 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 in writing, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to say :-
My said Invention relates to improvements in the construction of meters for
measuring water or other fluid, and in order that the same may be properly
understood and carried into effect, I have hereunto appended a Sheet of
explanatory Drawings representing certain modifications of my improved
apparatus, which I will particularly describe, premising that the same
reference letters mark the same or like parts in all the Figures.
Figure 1 is a vertical section of a meter embodying one modification of the
improvements. The details are contained in a chamber, which in this
example is of a shape resembling that obtained by placing two truncated
cones with their bases together, and which is formed by two castings A, A',
united by flanges a, a', at the middle. The measuring is effected by means of
a compound diaphragm B, C, working to and fro in the chamber, and dividing
it into upper and lower compartments D, D¹. The diaphragm consists of a
central metal portion B, which is represented in section in Figure 1, and sepa-
rately in plan in Figure 2, and is attached to an annular portion C of a flexible
material, such as leather or vulcanised rubber; the outer edge of this last
being fixed in the joint running round the chamber D, D¹, and formed by the
flanges a, a¹. The valves which regulate the passage of the fluid alternately
to and from the opposite sides D¹, D, of the diaphragm B, C, are arranged in
the central metal part B thereof. This part B consists of upper and lower
discs, contrived so as on being fixed together by screws to nip and hold the
inner edge of the flexible part C, and the space between the discs is divided
into two separate compartments, the inlet compartment E and the oulet com-
partment F, by flanges across the middle. The compartments E, F,
communicate respectively with the inlet and outlet apertures through the sides
of the meter by means of flexible tubes arranged in coils to permit of their
accommodating themselves to the movements of the diaphragm. In Figure 1
only the coiled tube V communicating with the outlet is shown, the other being
in the front half supposed to be removed in the section. Each internal
chamber E, F, has two openings e, e¹, and f, f¹; one e, f, through the top,
and the other e, f, through the bottom of the diaphragm B, and directly.

page_text: opposite to the former. Each pair of openings e, e¹, f, f¹, is controlled by a'
single disc valve G, H, lying between them, the moving up or down of which'
closes the top or bottom opening in each case. The distance between the
opposite ports or apertures e, e¹, or f, f, is exceedingly short, being equal to the
thickness of the valve G or H, and the slight space necessary for the passage
of the fluid through one of the openings; and in consequence of this arrange-:
ment not only is the effective discharge or passage area always the same, (one
aperture being opened precisely as the opposite one is being closed,) but also
there is no appreciable column of fluid between the ports, the motion of which
has to be reversed. The two valves G, H, are fixed upon spindles g, h, jointed
to opposite ends of a beam or lever I, centred midway between them on a pair
of small brackets i on the top of the diaphragm B, in such a way that the two.
valves are always in opposite positions, except at the instant of reversal. To
one end of the beam I there is jointed a peculiarly shaped lever J, formed with
two side plates, as shown in Figure 2, and to the other end of the beam I
there is jointed a link K (also double sided), which is connected to the lever J
by a pair of slotted links L, a pinj on the lever working in the slot of each
link L, whilst a steel spring M is on each side applied to the lever pin j and
to a pin l, on the inner end of each slotted link L, in such a way as to produce
a tension between the lever pins j and the outer ends of the slotted links L,
where they are jointed to the beam link K. The action of this arrangement
is to keep the valves G, H, firmly against their seats, except at the instant
they have to change their positions. The change of the valves is effected by a
movement of the peculiarly-shaped lever J, brought about as the diaphragm
B, C, reaches either end of its stroke by the tightening of a check strap N, N¹,
attached to the lever J and to the top and side of the chamber D. Both ends
of this check strap are brought through between the flanges a, a', and by
adjusting their lengths the stroke of the meter can be made to accurately
measure a determinate quantity. The motion of the lever J is limited in its
upward direction by a stop P, and in its downward direction by coming in.
contact with the disc B. In Figure 1 the diaphragm B, C, is supposed to
have just completed its downward movement, to have effected the reversal of
the valves, and to be about to commence its upward movement, the arrows-
indicating that the fluid is entering the lower compartment D₁ beneath the
diaphragm, whilst the fluid in the upper compartment D is being discharged.
As the diaphragm B, C, approaches the top of the meter the strap N will
become tightened, which will cause the lever J to gradually turn down, and
this movement will cause its pinsj to approach the end of the valve beam I,
which is centre to the beam link K. Whilst this takes place the valves G, H,

page_text: will be held in their present positions with increased firmness in consequence
of the springs M becoming more strained; but as the movement continues the
lever pins will pass the centre of the beam link K, whereupon from the
position of the parts the tendency of the springs M will be to throw downward
the links K, L, and at the same time to reverse the lever I and valves G, H,
and
press the latter firmly against their opposite seats. Counting mechanism
of the ordinary kind is applied to register the number of double strokes made
by the diaphragm B, C, and the first ratchet wheel Q of this mechanism is
acted upon by a catch R carried by a lever S, acted upon by the diaphragm
B, C, each time it makes its upward stroke. A safety valve T is in some
cases applied to the outlet chamber F of the diaphragm B to provide against
injury from back pressure. This valve is double, and consists of two washers
(T; T, Figure 3), applied to the outsides of apertures on opposite sides of
the diaphragm B, being fixed on a single spindlet passing across. The
washers T, T¹, are of an elastic or flexible material, and they can be screwed
up more or less tightly. When the back pressure is sufficiently great to lift
the washers the fluid can pass directly through the diaphragm, and so be
incapable of doing injury.
The details of the meter may be considerably modified without departing
from the principal features of improvement. Thus, a piston or other moving
partition may be substituted for. the flexible or partially flexible diaphragm.
Or a different form of chamber may be used; thus the chamber may be
shaped so that the diaphragm may have a vibrating motion as though moving
about a hinge at one end or side, in which case the inlet and outlet commu-
nications may be arranged at the part of the diaphragm having the least
motion.
In some cases the peculiarly-shaped lever (J) may be dispensed with, and
a spring may be applied to act tensionally between one end of the valve
beam (I) and the outer end of the beam link (K), stops being provided to
limit the motion of the link in opposite directions, whilst the check or stop
which limits the stroke of the diaphragm and causes the reversal of the
valves (G, H,) is arranged to act directly on the beam link. Or, instead of
the slotted links L and springs M, shown in Figures 1 and 2, there may be
substituted two links L, m, of rubber, as shown in Figures 3 and 4, which are
respectively an elevation and a plan of the diaphragm B, and valve details as
fitted with this slightly modified arrangement. These rubber links L, m, are
confined between cheeks j, upon the side plates of the lever J, being extended
beyond these to the joint end of this lever merely to obtain sufficient length
for the proper action of their elasticity.

page_text: In Figure 3, the diaphragm B is shown in elevation, and projecting from its
under side are seen the inlet and outlet mouthpieces U, V, upon which the
coiled flexible tubes herein-before referred to are fixed.
Having thus particularly described my said Invention, and the manner in
which the same is or may be used or carried into effect, I have to state that I
do not restrict myself to the precise details herein-before described or delineated,
but that what I consider to be novel and original, and claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is, the con-
structing, arranging, and applying of the valvular details of reciprocating fluid
meters substantially as herein-before described.
In witness whereof, I, the said William Dingwall, have hereunto set my
hand and seal, this Twenty-sixth day of December, in the year of
our Lord One thousand eight hundred and sixty-one.
WILLIAM DINGWALL. (L.S.)