AN IMPROVEMENT OR IMPROVEMENTS IN THE MAKING OR CONSTRUCTION OF METERS OR APPARATUS FOR MEASURING WATER OR OTHER FLUIDS
Year: 1841

page_text: TO ALL
WHOM THESE PRESENTS SHALL COME, I, ANDREW
MCNAB, of Paisley, in the County of Renfrewshire, Engineer, send greeting...
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her.
Letters Patent under the Great Seal of Great Britain, bearing date, at
Westminster, the Seventh day of July, in the fifth year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said
Andrew McNab, Her especial licence, full power, sole privilege and authority,
that I, the said Andrew McNab, my exors, admors, and assigns, and such
others as I, the said Andrew M°Nab, my exors, admors, and assigns, should at
any time agree with, and no others, from time to time and at all times during
the term of years therein mentioned, should and lawfully might make, use;
exercise, and vend, within England and Wales, and the Town of Berwick-
upon-Tweed, my Invention of "AN IMPROVEMENT OR IMPROVEMENTS IN THE
MAKING OR CONSTRUCTION OF METERS OR APPARATUS FOR MEASURING WATER OR
OTHER FLUIDS;" in which said Letters Patent is contained a proviso that I,
the said Andrew McNab, shall cause a particular description of the nature of
my said Invention, and in what manner the same is to be performed, to be
enrolled in Her Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters Patent,
as in and by the same, reference being thereunto had, will more fully and
at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Andrew McNab, do hereby declare the nature of my said Invention of an

page_text: improvement or improvements in the making or construction of meters or
apparatus for measuring water or other fluids, to consist in the certain new
arrangement or construction of apparatus or machinery, by which a vibrating
blade or vane is caused to indicate the amount of water or other fluid passed
through the meter; and the manner in which the same is to be performed
and carried into effect will be seen by reference to the annexed Drawings and
the following description. The scale to which the annexed Drawings are
made is marked thereon, and the same letter of reference indicates the same
part of the apparatus in the various Figures there represented.
DESCRIPTION OF THE DRAWINGS.
Figure 1 represents a sectional elevation, Figure 2 a transverse section,
and Figure 3 a plan, of a meter. In these Figures a, a, a, a, represent a
circular drum or case, provided with a stop or stationary division A; B is the
vane or blade which moves on the center 6, while the inlet C and slide
valve D guide the water or other fluid alternately to each side of the blade or
vane B, which is forced forward by the pressure of the column from which
the meter is supplied. The stop or division A, and the moving vane or blade B,
are packed by leather or other suitable substance so as to make them water-
tight, and the axis on which the vane or blade B revolves is carried through
cup leathers at one side of the circular drum, or case a, a, a, a, where it is
provided with the spur wheel E, geering into the horizontal rack F, as seen
at Figures 1 and 3, which carries the parts G, H, and I, the friction roller I
being supported on the vibrating lever K; thus, as soon as the-vane or blade B
has been forced forward by the pressure of the water or other fluid about
three quarters of a revolution on its center b, the rack Fis traversed the
distance from one end to the other of the lever K, when the part H pressing
against the supporting catch L, 'the lever K-is relieved, and instantly vibrates
by the pressure of the weight G; the slide valve D is connected with the
vibrating lever 'K by means of the connecting rod m, so that the vibration of
the lever K traverses the valve D, and directs the water or fluid to the opposite
side of the vane or blade B, which is consequently forced back, and the amount
of water or other 'fluid already received by the meter escapes by the outlet
pipo M, and thus the alternating vibration of the vane or blade B metes or
measures the water or other liquid with which it is supplied. By this improved
construction of meter, it will be remarked that no movement of the slide
valve D takes place until the vane or blade B is at the end of its vibration,
and that such movement is instantaneous and dependant on the striking off of
the spring catch L, so that every movement of the valve D metes or measures

page_text: off an equal and exact amount of fluid, which can be recorded by a train of
wheels similar to an ordinary gas meter.
But the arrangement which I prefer for recording the movement (of the
vane B is by carrying a small spring catch from the valve D, as seen at cat
Figure 1, and resting on a ratchet wheel Natic, Figure 4, in which it gathers
a tooth at every traverse of the valve D. From the foregoing.description of
my Invention of an improvement or improvements in the making or construc-
tion of meters or apparatus for measuring water or other fluids, it will be
obvious that the same improvements may be variously modified and varied;
and I would particularly refer to the substitution of a continuous rotatory
movement of the vane or blade, in place of the alternating movement already
described, which, with a slight variation in the arrangement, would answer the
same purpose; but this and other variations must depend on the purpose
for which such meter is to be used, and can be varied, according to circum-
stances, by any person competent to construct machinery for this nature. And
as regards the machinery for counting or telling the number of traverses or
vibrations of the blade or vane by which the water or other liquid is to be
measured, it may be constructed in various ways (to which I lay:no claim),
to indicate each opening of the inlet valve as it passes the center. It may be
remarked that meters of this nature require no more power to move them.than
is sufficient to overcome the friction of the moving parts and the.clevation
of the part G, which is very small, so that water or other fluid, meted or
measured by an apparatus of this nature, may be carried nearly to the same
clevation from which it is supplied; while the small pressure required on the
revolving blade or vane presents little risk of breakage, and consequent
inaccuracy. Added to these advantages, the small cost at which the apparatus
may be constructed, and slight risk there is of it getting out of order, are
recommendations worthy of attention. Finally, I would remark that though
less convenient, the blade or vane may remain stationary while the cylinder is
revolved, but I have represented such an arrangement as, with my present
experience, I consider the best, and which I have found to answer the desired
object of meting or measuring water and other fluids.
Having now described the nature of my Invention, and the manner in which
the same may be performed and carried into effect, I would remark that my
improvements are not limited to the precise arrangements, of machinery herein-
before described, but that the same may be effected by using any of the
well-known valves or cocks used for distributing steam, water, or other fluid,
on vibrating or revolving blades or vanes, and that, although I do not claim
any individual or separate part of the machinery herein-before set forth and

page_text: described, I do claim such apparatus or combination of parts as applied to the
meting or measuring of water or other fluids. And I further claim such
modification of the same for meting or measuring water or other fluids in
which a vibrating or revolving blade or vane is used to indicate the quantity,
together with the gradual and uniform elevation of a weight, for the purpose
of instantaneously reversing the valve, by which the supply of water or other
fluid is regulated. . And such improvement or improvements being to the best
of my knowledge and belief new, and never before used in that part of Her
Majesty Dominions called England, I deliver this as a true and faithful Speci-
fication of the same..
In witness whereof, I, the said Andrew M°Nab, have hereunto set my
hand and seal, this Third day of January, in the year of our Lord