Year: 1887

page_text: Date of Application, 6th Jan., 1887
Complete Left, 6th Oct., 1887
Complete Accepted, 6th Mar:, 1888
1, SAMUEL AUGUSTINE DE NORMANVILLE, of 26 Gloucester Road, Kensington, in
the county of Middlesex, Gentleman, do hereby declare the nature of this Invention
to be as follows:-
My invention consists in improvements upon that class of liquid meter, wherein a
slotted piston has a combined rotary and sliding motion upon a boss or pivot, within
a chamber of suitable form.
In the construction of my improved meter, I prefer to employ a chamber having an
internal periphery similar in principle to that shewn and described in the specification
and drawings accompanying the Letters Patent granted to Lawrence, Davison and
Lawrence, No. 258 of 1853, and 1 employ. a piston, somewhat similar to that shewn
and described in the specification and drawings accompanying the Letters Patent
granted to J. Reid, No. 3323 of 1870.
The internal parallel slot in the piston is fitted to slide, practically liquid-tight, upon
a boss pivotted eccentrically within the chamber, and such boss therefore divides the
internal space of the piston into two parts. The curve of the internal periphery of
the said chamber is such, that, no matter what may be the position of the piston, it
always maintains contact with the said periphery at both ends. That part of the
curve extending for a short distance in each direction from that end of the ininor axis,
further from the centre of the aforesaid pivot, I preferably form as an are of a
circle struck from the said pivot, which is necessarily situate upon the said
minor axis.
The ends of the chamber are flat surfaces, and it will be obvious that the aforesaid
piston and boss are of the same depth as the said chamber.
An inlet and an outlet port are provided in one of the ends of the cylinder, in such
a position, that when the piston is at right angles to the minor axis of the chamber,
and therefore bisected by the boss, the said ports are covered by the piston and open
only into its respective ends, intercommunication being prevented by the aforesaid
boss. The said ports are preferably of such shape and dimensions, that they extend
almost to the exterior outline of the piston when in the aforesaid position, and nearly
to the edges of the boss. I may make small extensions of the ports at certain points
[PQ27

page_text: extending beyond the general outline of such ports, to make the opening of one port
more nearly co-incident with the closing of the other. Starting from the last nained
position, the action of the apparatus is as follows:-the water entering one end of the
piston by the inlet port, communicates a sliding movement to the said piston, but the
advancing end being in contact with the curved wall of the chamber, which here is so
figured as to present an easy angle, the aforesaid sliding movement is immediately
combined with a rotary movement, and these said combined movements uncover the
ports upon opposite sides of the piston, so that the water enters between one side of
the piston and the chamber wall, and assists in the rotary movement, while the water
on the other side and from within the opposite end of the piston, flows away by the
outlet port. This action continues till the end of the piston enters upon that portion
of the curve forming an arc of a circle, when the motion necessarily becomes wholly
a rotary one, which carries the piston over this part of the curve. During part of
this rotary movement the ports are cut off from communication with the interior of
the piston.
When the point is reached, where the curve departs again from the circle, the ports
will have reopened into the respective ends of the piston, and a sliding movement will
be again combined with the rotary one until the first position is once more reached,
the piston meanwhile having become reversed, end for end.
By preference, I shape the external ends of the loop to a curve forming an arc of
a circle, having a radius equal to the distance from the centre of the aforesaid pivot
to the nearest part of the cylinder wall.
A stop may be provided upon each side of the boss, limiting the sliding motion of
the piston thereon to prevent undue friction when passing the circular part of the
chamber wall.
If desired inlet and outlet ports may be provided in both ends of the chamber,
communicating by suitable exterior passages, or the inlet may be formed in one end
and the outlet in the other.
I inay provide the piston with a telescopic or expanding action in a longitudinal
direction, actuated by a suitably disposed spring, so that it may better maintain
contact with the chamber walls. Such expanding action may be controlled by a stop
(preferably adjustable) arresting such action at such a point as to allow a good working
fit, but without unnecessary friction.
The telescopic action in this case is useful to enable the piston to clear any obstacle
coming between its rounded end and the chamber wall.
With such a telescopic piston, but allowing the expanding action free play, I may
use a chamber of a figure departing, to a certain extent, from the theoretical figure
described, such divergence being compensated by the expanding action of the piston,
or even a real cylinder, i.e., of circular section, might be used.
To give additional stiffness to such expanding pistons, I may connect the two ends
by a pair of telescopic tubes, passing along the axis of the slot and through a water-
tight fitting perforation in the boss, such tubes forming a convenient mounting or
receptacle for a helical expanding spring.
The usual indicating mechanism is employed in my apparatus and may be actuated
by a spindle connected with the aforesaid boss.
AMBROSE MYALL, C.E.,
Agent for the Applicant.

page_text: 1, SAMUEL AUGUSTINE DE NORMANVILLE of 26 Gloucester Road, Kensington, in
the county of Middlesex, Gentleman, 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 :-
My invention consists in improvements upon that class of liquid meter wherein a
slotted piston has a combined rotary and sliding motion upon a boss or pivot within a
chamber of suitable form.
In the construction of my improved meter, I prefer to employ a chamber having
an internal periphery similar in principle to that shewn and described in the
specification and drawings accompanying the Letters Patent granted to Lawrence,
Davison & Lawrence No. 258 of 1853, and I employ a piston somewhat similar to
that shewn and described in the specification and drawings accompanying the Letters
Patent granted to J. Reid, No. 3323 of 1870.
In the accompanying four sheets of drawings Fig. 1 is a plan of a water meter
constructed according to my invention with the cover and registering apparatus
removed. Fig. 2 is a similar plan shewing the piston in a different position and
Fig. 3 is a cross-section, through the line A A in Fig. 1. Fig. 4 is a plan of a meter
constructed according to my invention in a somewhat modified form, Fig. 5 is a plan
of a telescopic piston and Fig. 6 is a cross section through the line B, B, in Fig. 5.
Similar letters of reference refer to similar parts throughout the drawings.
In the meter shewn in Figs. 1. 2 and 3, the piston, C. is formed with an internal
parallel slot fitted to slide practically liquid tight upon a boss D, pivotted eccentrically
within the chamber E upon a pin or stud F, and such boss D therefore divides tho
internal space of the piston into two parts. The curve of the internal periphery of
the chamber E is such, that no matter what may be the position of the piston C, it
always maintains contact with the said periphery at both ends. A convenient
method of generating the curve is first to decide the position of the pivot centre F
upon the minor axis Z, Z, then to place the piston in the position shewn in Fig. 1
and describe a curve Y, Z, Y', (not necessarily part of a circlo) passing through Z¹
and tangential to the piston ends, the piston being then moved about the pivot F, with
one end always in contact with the said curve Y, Z, Y, the remainder of the curve
will be generated by the other end of the piston. And if the piston ends, as shewn,
are formed to the radius F, Z, a part of the curve extending a certain distance on
each side of Z, will be a portion of a circle with radius F, Z, but it is evident that the
general figure of the chainber may be modified to an infinite extent, provided always
that its form is such that the piston always maintains contact at both ends with the
cylinder wall during the whole of its rotation. One modification which has been
found to work well in practice is shown in the subsequently described Fig. 4. The
bottom H and the top J of the chamber E, are flat surfaces, and the piston C and
boss D are of the same depth as the chamber. An inlet port K and an outlet port L

page_text: are provided in the bottom H of the chamber, communicating with nozzles K¹, L'.
These ports are in such a position that when the piston is at right angles to the minor
axis Z, Z, as shewn in Fig. 1, and therefore bisected by the boss D, they are covered
by the piston and open only into its respective ends, intercommunication being pre-
vented by the boss. The said ports are preferably of such shape and dimensions that
they extend almost to the exterior outline of the piston and nearly to the edges of the
boss D), when the piston is in the position shewn in Fig. 1. Small notches or
extensions N of the ports may be provided to make the opening of one port more
nearly coincident with the closing of the other, without practically diminishing the
lap of the piston beyond the edges of the ports. The actual position and size of the
ports may be varied within certain limits, provided that they are so placed that the inlet
and outlet ports can never both be open at the same time on the same side of the piston,
or into the same end of the piston, and by this arrangement, an abutment or cut-off, to
prevent direct communication between the ports, such as is described and shewn in
the specification and drawings of Boult No. 1719 of 1882, is rendered unnecessary.
Starting from the position shewn in Fig. 1, the action of the apparatus is a follows;
the water, entering one end of the piston by the inlet port K, communicates a sliding
motion to the said piston, but the advancing end being in contact with the curved
wall of the chamber, which here is so figured as to present an easy angle, the
aforesaid sliding movement is immediately combined with a rotary movement in the
direction of the arrow, and these combined movements uncover the ports upon
opposite sides of the piston, so that the water enters between one side of the piston and
the chamber wall, and assists in the rotary movement, while the water on the other
side and from within the opposite end of the piston flows away by the outlet port L.
This action continues until the end of the piston enters upon that portion of the
curve forming an arc of a circle, when the motion necessarily becomes wholly a
rotary one, which carries the piston over this part of the curve-
e-During part of
this rotary movement, when the piston is in the position shewn by dotted lines in
Fig. 2, the ports are cut off from communication with the interior of the piston.
When the point has been passed where the curve departs again from the circle, the
ports will have reopened into the ends of the piston, as shewn by the position of
the said piston in full lines in Fig. 2, and a sliding movement will be again com-
bined with the rotary one, until the first position is once more reached, the piston
meanwhile having become reversed end for end. A stop may be provided upon
each side of the boss D, limiting the sliding motion of the piston thereon to prevent
undue friction when passing the circular part of the chamber wall.
If desired inlet and outlet ports may be provided in the top as well as the bottom
of the chamber, communicating by suitable exterior passages, or the inlet may be
formed in the top and the outlet in the bottom, or vice versa. A pin P is affixed
by a flange on its lower end to the top of the boss D and forms the medium of
communication with the registering mechanism. Such mechanism may be fixed to
the upper part of the broken away cover Q Fig. 3, but it is not shewn in the
drawings, as its construction is well understood and forms no part of my invention.
And any suitable means, other than that shewn, may be employed for communicating
motion thereto from the boss D.
The principles of construction and action of the modified form of meter shewn in
plan in Fig. 4. are the same as in the previously described meter, but no portion
of the internal periphery of the chamber necessarily forms part of a circle, so that
more or less sliding motion may be taking place during the entire rotation of the
piston.
The piston C, as here shewn, instead of sliding on a square or rectangular boss,
although such construction could be employed, moves on a sleeve or roller D on the
pivot F, so that the sliding friction of the piston on the boss is more or less
obviated, and it is evident that this arrangement could be applied to the ineter shown
in Figs. 1. 2 and 3. As in this case the sleeve or roller cannot be used to com-
municate motion to the registering apparatus, I prefer to employ for this purpose
a short pin journalled in the cover of the meter and provided at its lower ond

page_text: with a rectangular flange which will slide in the piston slot, but will turn with it as
it rotates, and the pivot F and sleeve D are reduced in height sufficiently to
allow room for the said flange.
The piston, as shewn in Figs. 5 and 6, may be made in two parts C and C³, so that
it can have a telescopic or expanding action in a longitudinal direction actuated by
helical springs contained in cylindrical cavatios and guided by pins S, S. One or
more of these springs would be placed on each side, or flat springs T might be
used instead-An outlet for the water behind the pin S must be provided oither
by a hole S' in the side of the piston, or a longitudinal groove in the pin, or in the
hole in which it slides.
The object of the expanding action is to maintain better contact with the chamber
walls and such action may be controlled by a stop (preferably adjustable) arresting
the action at such a point as to allow a good working fit without unnecessary friction.
This telescopic arrangement would enable the piston to clear any obstacle coming
botween its rounded end and the chamber wall.
Again with this telescopic action, but allowing free play to the expansion, I may use
a chamber departing somewhat from the figures previously described, such divergence
being compensated by the expanding action, but in practice I prefer to adhere to the
figures wherein the piston ends always maintain contact, without requiring any
expansion.
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:
1. In a liquid meter, the combination consisting of a slotted piston having a com-
bined rotary and sliding motion upon a boss or pivot, ports opening to the interior of
the said piston to assist such combined motion, and a chamber of such form that the
said piston always maintains contact at both ends with the wall of the said chamber,
and prevents direct communication between the inlet and outlet ports without the
necessity for any fixed "abutment," or other equivalent device, substantially as herein
set forth.
2. The combination of parts forming a liquid meter constructed substantially
as herein described and shewn with reference to Figs. 1. 2 and 3 of the accompanying
drawings.
3. The combination of parts forming a liquid meter constructed substantially as
herein described and shewn with reference to Fig. 4 of the accompanying drawings.
4. In a liquid meter of the class hereinbefore described, the use of a telescopic or
expanding piston, substantially as set forth.
5. The telescopic or expanding piston, for use in a liquid meter, constructed sub-
stantially as herein described and shewn with reference to Figs. 5 and 6 of the
accompanying drawings.
11
11007
AMBROSE MYALL,
21, Cockspur Street, London, S.W.,
Agent for the Applicant.