IMPROVE- MENTS IN FLUID METERS
Year: 1882

page_text: LETTERS PATENT to Charles Denton Abel of No 28 Southampton Buildings
Chancery Lane, in the County of Middlesex for an invention of "IMPROVE-
MENTS IN FLUID METERS Communicated to him from abroad by Charles
Schreiber of Paris, France
"
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel at the
Office of the Commissioners of Patents on the 24th May 1882.
"
CHARLES DENTON ABEL of No 28 Southampton Buildings Chancery Lane in the
County of Middlesex "IMPROVEMENTS IN FLUID METERS [Communicated to him
from abroad by Charles Schreiber of Paris, France]
This invention relates to that description of fluid meters in which the fluid
under pressure is caused to impart a reciprocating motion to pistons in cylinders
of definite capacity, the strokes of the pistons being registered on a counter.
According to the present improvements two such pistons are arranged side by
side in two cylindrical cavities in a casing, the pistons being made to perform their
strokes alternately in opposite directions and the rod of the one piston being made
to actuate the slide valve of the other piston by the following arrangements. The
piston rod of each cylinder passes through a guide at the one end of the cylinder
in which guide is a sliding piece having a slot through which the piston rod passes.
This has at its extremity a lateral incline or cam face, and a second one on its
opposite side at a certain distance from the end, which inclines, in passing
alternately through the slot of the sliding piece as the piston rod moves to and fro,
impart to it a to and fro motion at right angles to that of the piston rod. The
piston rod has grooves on the sides opposite those on which are the inclines, into
which grooves take projections on the guide of the sliding piece, which thus also
acts as guide to the piston rod. The guide of the sliding piece is cast in one with
a plate covering the end of the cylinder, which plate forms the face for the slide
valves to work against.
The slide valves are contained in separate chambers and work on the outer face
of the said plate and the motion of the sliding pieces is imparted to them by means
of a fork on the underside of an extension of the slide valve passing through a slot

page_text: in the said plate and embracing a neck on the sliding piece. The extension of the
slide valve covers the said slot with a certain amount of lap in all positions so that
no fluid can leak from the slide chamber of the one cylinder into the other cylinder
through the said slot. The slide valves are of the ordinary D kind, governing two
ports leading to the opposite ends of the cylinder and a third port leading to an
escape passage for the fluid formed in the sides of the casing.
The ends of the piston rods work up and down in closed chambers formed in the
cover of the casing, and the one rod is made to impart motion to a counter by
means of a rod having a helical twist, which passes with its lower end into a
corresponding helical groove or recess in the piston rod while its upper end passes
through a stuffing box into the counter chamber, where it has a disc or arm
carrying a pawl in gear with a ratchet wheel that actuates the train of the wheels
of the counter. Thus at each stroke of the piston rod the helical rod has a partial
rotation imparted to it whereby a step by step motion is imparted to the counter.
As in the above described improved construction of fluid meter the piston rods
and slide valves work without stuffing boxes, there is very little friction of the
moving parts to overcome and the meter will consequently work accurately with
comparatively little fluid pressure, in addition to which, being of simple con-
struction it is not liable to get out of order or require repair, and the several parts
are so arranged that they can easily be inspected.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Denton Abel in the Great Seal Patent Office on the
22nd November 1882.
CHARLES DENTON ABEL of No 28 Southampton Buildings, Chancery Lane, in the
County of Middlesex IMPROVEMENTS IN FLUID METERS A communication to me
from abroad by Charles Schreiber of Paris, in the Republic of France
This invention relates to that description of fluid meters, in which the fluid
under pressure is caused to impart reciprocating motion to pistons in cylinders of
definite capacity the strokes of the pistons being registered by a counter. I will
describe the construction and arrangement of a fluid meter according to this
invention referring to the accompanying drawings.
Fig: 1 is a vertical section on the line N N of the sectional plan fig: 2, and
fig: 3 is a part vertical section shewing the mechanism for moving the counter.
In one casing are two vertical cylinders A A each fitted with a piston B which
as will be presently described works a slide for supply and discharge of the other
cylinder. For this purpose the piston rod has on it two inclines C C which as the
piston approaches the end of its up and down strokes cause a sliding piece E to
move to and fro horizontally, the piston rod being itself guided in a straight line
by studs H entering grooves D in the sides of the rod. The slide G is of the usual
D kind commanding ports to both ends of the cylinder and a middle discharge
port, communicating with outlets X. A stud K projecting down from the slide,
passes through a slot F and engages in a notch in the sliding piece E, the
movement of which is thus communicated to the slide which covers the slot F.
As no stuffing is employed for the piston rods or slides, there is comparatively
little friction so that the meter is worked by fluid under very low pressure. The
counter is worked by the mechanism shewn in Fig 3. One of the piston rods R
has a slot, through which passes a helically twisted bar S which, as the piston
makes its up and down strokes is caused to turn partly round its axis and to
return. On a disc at the top of the bar S is a spring pawl, engaging with the
teeth of a ratchet wheel T, that is geared to the counter, which, registering the
number of strokes of the piston, thus records the volume of fluid passed through
the meter. As the piston rods work in closed spaces U and are guided, the meter
may be placed either vertically or in another attitude.
Being simple in construction, the Meter is not liable to damage or derangement,
and it can readily be taken apart for inspection or repair of the working parts.
Having thus described the nature of the said invention, and in what manner the
same is to be performed, as communicated to me by my foreign correspondent, I
claim:
The construction of fluid meter with two cylinders and pistons, each piston
being arranged to work the slide of the other cylinder substantially as herein
described
In Witness whereof, I, the said Charles Denton Abel have hereunto set my
hand and seal this twenty second day of November in the year of our Lord.