An Improved Liquid Meter.
Year: 1889

page_text: Date of Application, 23rd Feb., 1889
Complete Specification Left, 23rd Dec., 1889-Accepted, 25th Jan., 1890
An Improved Liquid Meter.
I, HENRY CONRAD AHRBECKER of 117 Stamford Street in the County of Surrey,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to a simple and compact construction of meter for measuring
the quantity of water or other liquid passing through the apparatus, the chief object
which I have in view being the working of the valves which alternate the pressure
on the piston in such a manner that, whether the flow through the meter be quick
or slow, the stroke of the piston shall always be reversed with certainty at each
extreme. The meter consists of a vertical cylinder fitted with a packed piston,
with its rod passing through packing in the cylinder cover into a closed chamber
above the cylinder cover, which chamber contains the slide valve and the gear for
working it, and is surmounted by a chamber containing a counter with its dial and
index visible through a glass at the top. The supply pipe opens into the closed
chamber, in which is arranged a horizontal slide valve of D kind governing
ports to both ends of the cylinder and a discharge port in communication with
the discharge pipe.
By preference, the slide valve is arranged to slide under a spring cover, so that it is
to a great extent relieved from the pressure of the liquid in the closed chamber.
A pin projecting from the piston rod works in the slot of a link connecting it to
a slot in one arm of a three armed lever; this arm in its middle position is
horizontal, and the other two arms are vertical, the one extending upwards and the
other downwards, and both having rollers mounted on their ends.
The roller of the upper arm moves under a wedge shaped arm which is pressed
down by a weight or spring; the roller of the lower arm moves to and fro between
two tappets fixed on the slide rod. The action of this valve gear is as follows.
As the piston approaches the end of its upstroke, it begins to move the three
armed lever, the upper roller of which in passing under the protuberance of the
wedge shaped arm raises it in opposition to the weight or spring; as soon as the
roller passes the apex of the wedge, it is caused to make a sudden stroke onwards,
and the roller of the lower arm is thus made to meet one of the slide rod tappets
and move it shifting rapidly the slide valve. When the piston approaches the end
of its down stroke, a similar action takes place in the opposite direction. The slide
rod carries a pawl which at every stroke turns a ratchet wheel one tooth, another
pawl preventing the wheel from retreating. A worm on the axis of the ratchet
wheel works a vertical spindle which passes through packing into the counter
chamber above and works the gearing of the counter. In cases where the stroke
of the piston is considerable, I fit the piston rod with a head sliding in a tube
between stops therein, this tube passing through packing into the closed chamber
and there working the valve gear. As the tube is only moved as the piston is
approaching the extremes of its stroke, the extent of movement of the tubo is
small as compared with that of the piston, and consequently the valve gear and
closed chamber containing it may be compact notwithstanding considerable extent of
piston stroke.
Dated this 23rd day of February 1889.
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
An Improved Liquid Meter.
I, HENRY CONRAD AHRBECKER of 117, Stamford Street in the County of Surrey,
Engineer, 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 relates to a simple and compact construction of meter for measuring
the quantity of water or other liquid passing through the apparatus, the chief object
which have in view being the working of the valves which alternate the pressure on
the piston in such a manner that whether the flow through the meter be quick or
slow the stroke of the piston shall always be reversed with certainty at each extreme.
The meter consists of a vertical cylinder fitted with a packed piston with its rod
passing through packing in the cylinder cover into a closed chamber above the
cylinder cover which chamber contains the slide valve and the gear for working it
and is surmounted by a chamber containing a counter with its dial and index visible
through a glass at the top.
The supply pipe opens into the closed chamber in which is arranged a horizontal
slide valve of D kind governing ports to both ends of the cylinder and a discharge
port in communication with the discharge pipe.
By preference, the slide valve is arranged to slide under a spring cover, so that it is
to a great extent relieved from the pressure of the liquid in the closed chamber.
A pin projecting from the piston rod works in the slot of a link connecting it to a
slot in one arm of a three arined lever this arm in its middle position is horizontal,
and the other two arms are vertical, the one extending upwards and the other
downwards, and both having rollers mounted on their ends.
The roller of the upper arm moves under a wedge shaped arm which is pressed
down by a weight or a spring; the roller of the lower arm moves to and fro between
two tappets fixed on the slide rod. The action of this valve gear is as follows. As
the piston approaches the end of its upstroke it begins to move the three armed lever
the upper roller of which in passing under the protuberance of the wedge shaped arm
raises it in opposition to the weight or spring; as soon as the roller passes the apex
of the wedge it is caused to make a sudden stroke onwards and the roller of the lower
arm is thus made to meet one of the slide rod tappets and move it, shifting rapidly the
slide valve. When the piston approaches the end of its downstroke similar action
takes place in the opposite direction. The slide rod carries a pawl which at every
stroke turns a ratchet wheel one tooth, another pawl preventing the wheel from
retreating. A worm on the axis of the ratchet wheel works a vertical spindle which
passes through packing into the counter chainber above and works the gearing of the
counter.
In cases where the stroke of the piston is considerable, 1 fit the piston rod with a
head sliding in a tube between stops therein, this tube passing through packing into
the closed chamber and there working the valve gear As the tube is only moved as
the piston is approaching the extremes of its stroke, the extent of movement of the
tube is small as compared with that of the piston and consequently the valve gear and
closed chamber containing it may be compact, notwithstanding considerable extent of
piston stroke.
In the accompanying drawings Fig. 1 is a vertical section. Fig. 2 is a back
elevation of the gear for working the slide valve and the spindle of the counter and
Fig. 3 is a sectional plan on X X of Fig. 1.
A is a cylinder fitted with piston B suitably packed, and having a port opening
through the cover into, the cylinder above the piston and a passage and port D
opening through the bottom into the cylinder below the piston. The piston rod is
made with a head E which works freely within a tubular rod F that passes through
packing in the cylinder cover.

page_text: The head E of the piston rod and the internal collar of F on which E comes to
bear are notched so as to allow free passage for liquid into and out of the interior
of F. Above the cylinder is formed a chamber G which contains the valve gear and
into which opens the inlet pipe H, so that this chamber is subject internally to the
pressure of the supply. The outlet I communicates with the central exhaust port
between the two cylinder ports these ports being governed by a D slide valve J. The
rod K of the slide valve has two tappets projecting up from it and has jointed
on it a pawl ³ which engages with the teeth of a ratchet wheel L; another paw! I
prevents the wheel from turning backwards. On the spindle of the wheel L is a
worm gearing with a worm wheel 2 on a spindle that passes through packing into
a compartment M above, this compartment containing suitable counter gearing with
an index and dial that can be seen through a glass m. An arm frigidly attached to
the rod F has a stud capable of adjustment in a slot in the arm working in a slotted
link R which is connected with one arm of a three armed lever N by means of a stud
capable of adjustment in a slot in the lever arm. Another arm of this three armed
lever, which three armed lever or its equivalent is hereinafter referred to as the
tumbler, carries a roller n which is in the space between the tappets k¹² and a third
arm carries a roller n which is under a downwardly curved or inclined projection p of
a lever P. This lever P has attached to its end an adjustable spring purging it
downwards.
The purpose of this arrangement is to store up the energy of the piston and render
it available for moving the slide valve at the proper time independently of the
movement of the piston during the last portion of its stroke.
It is obvious that this result might be secured by the use of a weight instead of a
spring or by the use of equivalent arrangements for storing up such energy and
giving it out at the proper moment to move the slide valve.
The arrangements of the lever P with its spring an inclines acting upon the roller
of the tumbler and any equivalent arrangement is hereinafter referred to for con-
venience as the actuator.
The operation of the meter is as follows:
The slide valve J being in the position shewn in Fig. 1 uncovering the port that
leads to the passage D and putting the port leading to C in communication with the
outlet I, liquid under pressure flows from the chamber G hy the passage D to the
cylinder under the piston B, while liquid can flow from above the piston by C to
the outlet I.
The piston B is thus caused to ascend; after performing part of its upstroke
the head E of the piston rod meets the upper end of the tubular cavity of F and
during the rest of the stroke moves F up with it. The arm as it approaches the
end of its upstroke, through the medium of the slotted link R, moves the tumbler N
causing its roller to move along the projection thus raising the lever P and
straining the spring of the actuator; when the roller n' passes the most prominent
part of p the force of the spring purging down the lever P causes the roller n¹ to
pass rapidly towards the less prominent part of p and by the action of the roller n
upon the tappet pushes the slide valve to the position where it puts the upper part
of the cylinder A in communication with the chamber G and the lower part in com-
munication with the outlet 1. The piston now descends until the head E of the piston
rod meets the internal collar of F which then descends with the piston until its arm f
acting through the medium of the slotted link R on the tumbler N causes the
movements of the roller n and n¹ like those above described but opposite in direction,
whereby the slide valve J is rapidly shifted back to the position shewn in Fig. 1 and
the piston B is again caused to ascend.
k2
By means of the pawl ³ the ratchet wheel L is moved one tooth for every to and
fro stroke of the slide valve J, and this movement is communicated by the worm
worm wheel and its spindle to the counter in the compartment M. The index of
this counter consequently shews the number of up and down strokes of the piston B
aud, the capacity of the cylinder A being known, the quantity of liquid passing
through it is registered.

page_text: The rod F might be in one piece with the piston rod when the stroke of the piston
is comparatively short. But by the arrangement of F as shewn so as to be moved
only by the latter part of each stroke of the piston, the valve gear can be made
compact however long may be the stroke of the piston."
In order to secure the certain and complete shifting of the slide valve at or near the
end of the stroke of the piston in certain cases prior to my invention a subsidiary
cylinder and piston were employed to operate the slide valve at the required time.
In my invention I am enabled to accomplish this object without the intervention of a
subsidiary cylinder and piston, by means of such an arrangement as I have described
already, a sudden impulse is imparted to the slide valve at or near the end of each
stroke of the piston.
By this arrangement the slide valve remains unmoved and the port in action fully
open until near the end of the piston stroke when it begins to move and a complete
shifting is effected, not as in some prior arrangements by the final movement of the
piston, but wholly independently of such final movement by means of the energy
stored up in the train of parts intermediate between the piston rod and the slide
valve.
By making the accelerated movement of the slide valve independent of the final
movement of the piston, I get increased certainty of action; such certainty of action
cannot be secured where the movement of the slide valve depends on the final
movement of the piston, as this is apt to be variable owing to differences of pressure
and other circumstances.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what 1
claim is :-
1. The improved liquid meter constructed arranged and operating substantially
as hereinbefore described.
2. In a liquid meter of the kind herein referred to the use of a tumbler, such
as described and slotted link in combination with an actuator to govern the notion
of the slide valve, substantially as described.
3. In combination with the cylinder of a liquid meter having its parts governed by
a D slide valve the loaded lever P, the arm moved by the piston, the slotted link R,
the tumbler N. linked to f and carrying two rollers n engaging with the tappets on
the slide rod and n' moving along the downward projection p of the loaded lever
whereby the slide valve is shifted at each end of the piston stroke, substantially as
described.
Dated this 23rd day of December 1889.
ABEL & IMRAY,
Agents for the Applicant.