IMPROVEMENTS IN APPARATUS FOR MEASURING, PUMPING, OR OFTAINING MOTIVE POWER FROM LIQUIDS
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Stephen Alley at the Office of
the Commissioners of Patents, with his Petition, on the 11th
November 1872.
I, STEPHEN ALLEY, of Glasgow, in the County of Lanark, North
Britain, Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN APPARATUS FOR MEASURING, PUMPING, OR OFTAINING
MOTIVE POWER FROM LIQUIDS," to be as follows, that is to say :-
This Invention has for one of its objects the constructing of liquid
meters in an improved manner and so as to be accurate and reliable,
and not easily deranged, whilst comparatively economical in first cost.
The arrangements or slightly varied modifications thereof are also.
applicable for pumping or for obtaining motive power from liquids.
In one modification suitable for a water meter the casing, made to be
bolted in two halves; has formed within it a segmental annular chamber
in which there reciprocates a duplex segmental plunger connected with
the main centre of the casing by a radial arm attached to its middle.
Each end of the plunger has attached to it a bag of a suitable flexible
material, such as vulcanised rubber, and the month of each bag is

page_text: attached to the sides of the segmental annular chamber at places near
the mid-stroke positions of the plunger ends. With the reciprocation
of the duplex plunger these flexible bags are alternately turned inside
out and back again, and they serve as convenient and nearly frictionless
packing. The liquid has access through valves to the otherwise closed
parts of the annular chamber, which are separated from the plunger
by the bags and constitute the measuring spaces; and the plunger is
acted on by the liquid just as the piston of a cylinder would be. Two
duplex disc valves are used to cause the liquid to flow alternately into
and out of the measuring spaces, each valve being in a small recess
communicating with the measuring space and the inlet and outlet
openings opposite to each other. The two valves are on rods which are
jointed to two parallel levers, so that when one valve closes its inlet its
outlet is open, whilst the inlet of the other valve is open and the
corresponding outlet closed. The valves are reversed by the action on
one of the levers of a tumbling weight or spring; and this tumbling
weight is turned over to each side alternately by the radial arm of the
plunger. The tumbling weight and a portion of the valve details
conveniently occupy a central space within the annular chamber, and
the other valve details occupy the space between the ends of that
chamber.
The counting mechanism, which may be of the usual kind, is actuated
by a spindle turned by the radial arm of the duplex plunger. The
spindle has on it two small cones which can be adjusted more or less.
apart by a screw and which have on them a split or overlapping ring
that varies in diameter with the screw adjustment; the combination thus
forming a pulley, the diameter of which can be adjusted to correct the
recording action for differences in the capacities of the measuring
chambers. This variable pulley has connected to it on opposite sides
two rods which reciprocate with the rocking of the pulley and act on a
ratchet wheel forming the first wheel of the counting mechanism.
Each rod may have two or more catches or sets of catches having the
effect ef sub-dividing the pitch of the ratchet teeth. Where the
adjustable pulley is not required there may be substituted for it a
toothed wheel gearing with rack teeth on the rods.
The herein-before described combination of valve details and flexible
bag may be used with a cylindrical or other convenient form of
measuring chamber, the duplex plunger having substituted for it in.

page_text: such cases a single long piston or plunger with a flexible. bag at each
end of it; or a single flexible bag will answer the purpose if fixed to the
middle of the plunger and to the middle of the cylinder.
Rubber rings known as rolling packing may be substituted for the
flexible bags, or the plungers may be made to work through stuffing
boxes. In the case of segmental plungers and chambers, each rubber
ring is to be made of gradually varying thickness or section to suit the
different lengths of travel of each part. The plungers may be made
of glass, earthenware, or enamelled metal to reduce the friction,
particularly when working through stuffing boxes; and these materials
may also be used in some cases for making the chambers or cylinders.
When using any of the herein-before described modifications of
apparatus for pumping or for obtaining motive power from liquids, the
valve mechanism herein-before described may have substituted for it
valve mechanism of any suitable kind in use in existing pumps or
hydraulic motive-power engines.