Improved Automatic Prepayment Gas Meter.
Year: 1893

page_text: Date of Application, 18th Mar., 1893
Complete Specification Left, 12th Sept., 1893-Accepted, 18th Nov., 1893
PROVISIONAL SPECIFICATION.
Improved Automatic Prepayment Gas Meter.
We, WILLIAM ALEXANDER, Civil Engineer of 28 Rockybank Road, Devonshire
Park, Birkenhead, and WILLIAM EDWARD THOMPSON, Mechanical Engineer of
37 Madelaine Street, Liverpool do hereby declare the nature of this invention to
be as follows:-
:-
A novel and improved gas meter so constructed that on inserting a coin in a slot
or opening for that purpose a certain quantity of gas may be obtained and when the
correct amount has passed through the meter the supply is automatically cut off
until another coin is inserted. A number of coins may be inserted, one after the
other, up to an amount for which the meter may be regulated and the amount of
gas corresponding to the total number of coins so inserted may be obtained. An
index is attached shewing at any time the quantity of gas paid for but not then
consumed.
The mechanism may be attached to a meter of any pattern and does not require
one of special construction. It consists of two concentric toothed wheels with one
or more toothed wheels, carried in a frame, gearing into both of them and rolling
between them. One of the two concentric wheels is driven by suitable gearing
from the druin or bellows of the meter and the other is caused to revolve in the
opposite direction by means of a rack attached to it which is carried forward a
certain distance when a coin is inserted and causes the rolling wheels and frame to
advance proportionately. The wheel driven by the meter causes the rolling wheels
and frame to move back to their zero position when a stop attached to them
actuates a valve which cuts off the supply of gas. This mechanism is certain in its
action as it does not contain any frictional gearing.
The gearing between the meter and the rolling wheels is so arranged and
proportioned that when the rolling wheels are moved forward a certain distance, on
a coin being inserted, the meter while causing them to move back to their zero
position will pass a known quantity of gas and the distance to which the rolling
wheels are carried forward when a coin is inserted being adjustable, as hereinafter
described, the quantity of gas which may be obtained for each coiu inserted can be
adjusted to any amount.
The concentric and rolling wheels may be arranged either with one of the
concentric wheels, having teeth on its outer edge, placed inside of the other which
is of a larger diameter and has teeth on the inner edge of its rim, the rolling wheels
being placed in the space between them and gearing into both the inner and outer
wheels; or the concentric wheels may be in the form of crown or bevilled wheels of
the same diameter placed parallel to, and facing, each other with the rolling wheels
between them and gearing into both of them.
The frame carrying the rolling wheels also carries the index shewing the quantity
of gas paid for but not consumed. This index is in the form of a ring which moves
round with the rolling wheel frame and has divisions, marked on its face, which
pass a fixed pointer and are numbered so that they may be easily read off.
The means by which the wheel with rack attached is caused to revolve on
inserting a coin are as follows:-A lever works on a fulcrum which is in line with
the centres of the two concentric wheels and has attached to it a secondary lever
or arm carrying near its outer end two pawls or clicks one of which engages in the
rack attached to the wheel and the other in a fixed rack adjacent to it with its
teeth facing in the opposite direction. The arm when in its normal position lifts
the pawls out of the racks by means of a spring or counterbalance. The lever may
be moved backwards or forwards by any suitable means from the outside of the

page_text: meter such as a continuation of the lever through the casing etc. When a coin is
inserted in the slot or opening it falls on to the arm and if the lever is then moved
forward, the coin passes with it under a guide and depresses the arm, causing the
pawls to engage in the racks. The pawl engaging in the rack attached to the
wheel carries it and the wheel round a certaiu distance which may be regulated as
described hereinafter and the other pawl engaging in the fixed rack prevents the
lever being returned until it has been moved forward far enough to bring the coin
past the end of the guide, when the coin falls into a receptacle placed to receive it
and the arm being freed lifts the pawls and the lever may then be returned to its
original position. On this being done, another coin may be inserted and the wheel
and rack carried round a further distance equal to the first, and so on, until, when
a certain number of coins, for which the meter has been adjusted, have been
inserted, a stop on the frame carrying the rolling wheels and index causes the coin
slot or opening to be closed and so prevents any more coins being inserted until the
meter action carries the rolling wheels etc. back far enough to again open the coin
opening or slot.
The distance through which the lever causes the wheel with rack attached to
rotate is regulated thus:-The pawl which engages in the rack attached to the
wheel does not engage in the rack immediately on the coin coming under the guide
but rides over a carrier until it comes to the end of the same, when it drops
suddenly into the rack and forces it forward until it comes against a second carrier
which again lifts it out of the rack; the distance between the two carriers may be
reduced or increased and the distance through which the rack and wheel rotate
correspondingly altered and consequently the amount of gas obtainable for each
coin inserted may be adjusted to any desired quantity.
The mechanism is cased in and may be sealed so that it cannot be tampered
with. The ordinary meter index is retained as a check on the quantity of gas
consumed and the number of coins which should be found in the receptacle.
Dated this 17th dor of March 1802
W. ALEXANDER.
W. E. THOMPSON.
COMPLETE SPECIFICATION.
Improved Automatic Prepayment Gas Meter.
We, WILLIAM ALEXANDER of 28 Rocky Bank Road, Devonshire Park,
Birkenhead in the County of Chester, Civil Engineer and WILLIAM EDWARD
THOMPSON of 37 Madelaine Street, Liverpool in the County of Lancaster,
Mechanical 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:―
This invention has for its object certain improvements in that class of gas meter
through which, on the insertion of a coin or coins in a slot provided for the purpose,
a certain quantity of gas is allowed to pass, and the invention relates more
particularly to the coin freed or coin actuated mechanism therefor.
Our improved coin-actuated mechanism will be best understood from the
following description and by referring to the accompanying drawings, in which :-
Figure 1 is a front elevation :
Figure 2, a plan :
:-
Figures 3 and 4, vertical sections through line xx, Figure 1, viewed in opposite
directions: and,
Figure 5, a back elevation of the mechanism as a whole.
Figures 6 to 12 are detail views of separate parts of the mechanism.
In these―
A, is a portion of a meter with the mechanism in position: A¹ is a frame
carrying or supporting the latter and having a coin slot a and guide way formed

page_text: therein for purposes hereinafter described.
B and C are two concentric toothed
wheels, the one, B, being loosely mounted on a fixed spindle B¹ carried by the
aforesaid frame, and the other, C, fixed on a rotatable spindle C' which is driven
by the ordinary index gearing of the meter. Between these wheels B and C is a
frame D, loosely mounted on the spindle C¹ and carrying, in addition to two rolling
wheels D' and D', an index or dial E in the form of a ring, which has divisions
marked on its face inversely to the usual manner for the purpose of showing at any
time the quantity of gas paid for but not consumed. E' is a fixed pointer in front of
the dial E. The aforementioned rolling wheels D1 D2 gear, one with the toothed
wheel B, and the other with the wheel C and with each other, so that the dial or
index E is rotated in one direction when a coin is inserted, in a manner hereinafter
described, and in the reverse direction by means of the index gearing from the
drum or bellows of the meter. This epicyclic gear is an important feature of this
invention as it dispenses with the frictional arrangement employed for this purpose
in some prepayment gas meters and which is so uncertain in its action. We do not,
however, confine ourselves to the exact arrangement of rolling wheels above
described, as the same object can be attained by means of an epicyclic train of any
form, for instance, the concentric and rolling wheels may be arranged either with
one of the concentric wheels, having teeth on its outer edge, placed inside of the
other, which is of a larger diameter and has teeth on the inner edge of its rim, the
rolling wheels being placed in the space between them and gearing into both
the inner and outer wheels; or the concentric wheels may be in the form of crown.
or bevelled wheels of the same diameter placed parallel to and facing each other
with the rolling wheels between them and gearing into both of them. F is a
ratchet wheel loosely mounted on the aforementioned spindle B' and adapted to
rotate with the toothed wheel B. G is a pawl which, on the insertion of a coin,
operates the said ratchet wheel in the following manner :-
H is a frame in the form of a quadrant (shown best in Figure 5) mounted on the
central spindle B', and H' a handle for turning the said frame on its axis. This
frame, at its outer end, carries a spindle on which are mounted the afore-
mentioned pawl G and a second pawl G', also a weighted lever I, the pawl G is for
engaging the ratchet wheel F and the pawl G for a fixed rack J having its teeth
facing in the opposite direction to the teeth of the ratchet wheel, both pawls being
operated in a similar manner. In their normal positions, the pawls G and G¹ are
held out of engagement with their respective wheel and rack by a projection g
moving with the weighted lever I, and are therefore inoperative, but if a coin is
inserted, it rests partly in a pocket i, Figures 5 & 6, formed in one end of the
lever, and partly in the coin slot a, and, if the quadrant frame H carrying the
weighted lever and pawls be moved forward by the handle H', the coin passes
with it under a guide in the form of a groove K in the frame A and depresses the
weighted lever, causing the pawls to engage, the one with the ratchet wheel F, and
the other with the fixed rack J. The pawl engaging the ratchet wheel imparts to
the dial E (by means of the toothed wheel B and rolling wheel D¹) an angular
movement in a direction opposite to that in which it moves when driven by the
index gearing of the meter, the amount of such angular movement and, con-
sequently, the amount of gas obtainable for each coin inserted being regulated as
follows:
The pawl G, having a projection when moved forward, does not engage the
ratchet wheel F immediately on the coin coming under the groove K, but rides by
means of its projection on a fixed projection L until it comes to the end of the
latter, as shown in Figure 1, when it drops suddenly into engagement with the
wheel F and forces it round until (its projection having passed under guides L',
which have kept it in gear) it reaches a second projection 1 which raises it clear
of the ratchet wheel. These projections L L and guides L' are shown developed
in Figure 11, and, as one of them, L, with its guide, is adjustable in the direction
of its length by means of a set screw M¹ and curved slot m, Figure 5, it will be
evident that the distance between them can be varied, and consequently the pawl

page_text: will leave the ratchet wheel sooner or later and the dial be moved round a greater
or lesser distance according to the distance apart of the said projections. The
pawl G engaging in the fixed rack prevents the handle being moved backwards so
long as a coin is in the pocket, but when the coin falls into the box or receptacle
formed to receive it, both pawls are lifted by the weighted lever I clear of the
racks and the handle may then be moved back to its original position. On this
being done, another coin may be inserted and the process repeated.
N is a nosepiece on the frame D carrying the dial E, which, when the pointer
points to zero on the dial, raises the rod, if it be a wet meter, and actuates the
valve which shuts off the supply of gas, but it will be obvious that the same
nosepiece could be also arranged to shut off a valve on a dry meter.
In order to prevent the complete rotation of the index E by too great a
number of coins being inserted successively, which would cause the nosepiece N
to be forced onto the back of the valve rod or lever and damage the mechanism,
an arm or cam on the frame D is adapted in its rotation to force a spring
actuated pin or bolt d, Figure 7, across the path of the aforementioned frame H
which carries the pawls &G', thus rendering it inoperative until the meter
action has carried the cam O in the reverse direction sufficiently far to allow
the pin to spring back clear of the said frame. A somewhat similar bolt or
pin can be used in any arrangement for closing the coin slot for the same
purpose and forms an improvement in such. In place of causing a portion of a
lever or arm to come opposite the slot, the pin or bolt is caused to pass through
the sides of the slot or through guides attached so that it cannot be bent or
forced aside.
The quadrant-shaped frame H is made to dip, as shown at H2, so that, if a
coin be inserted in the slot a after the handle H' is pushed over, the latter on
its return will clear the coin owing to its dropping into the dip, and by this
means the length or height of the handle can be reduced. It will be observed
that a blank space e is left in the dial E, which, when the meter is not working,
is opposite the fixed pointer E', so that a person can see at a glance that all
the gas paid for has been consumed. To prevent persons obtaining gas
fraudulently by inserting a piece of wire or the like down the coin slot a and
pressing the pawl G on to the ratchet wheel F, a projection on the frame H
enters the groove K, closing the same.
The mode of action is as follows-
Having first regulated the distance apart of the projections L and L2, so that
a given amount of gas will be allowed to pass through the meter for a certain
coin, the latter is dropped in the coin slot a and rests in the pocket of the
weighted lever 1. The handle H and frame H are then moved forward and the
pawl G, after riding along the projection L, drops on to the ratchet wheel F,
rotating the same until it (the pawl) reaches the second projection L and is raised
clear of the said ratchet wheel. The coin now leaves the frame H and passes into a
receptacle in the meter, when the frame can then be turned back to its first position
ready for the next coin that is inserted, when the operation is repeated. The
movement of the ratchet wheel has turned the index or dial E a distance from zero
corresponding to the number of coins inserted, and the gas passing through the
meter turns, by means of the index gearing, the dial back again until zero is again
opposite the pointer, when the valve regulating the flow of gas through the meter
is closed, and no more gas allowed to pass through until another coin or coins is or
are inserted.
The ordinary meter index is retained as a check on the quantity of gas consumed
and the number of coins which should be found in the receptacle.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is-
1. In automatic prepayment gas meters, an arrangement of wheels in the form

page_text: of an epicyclic train connecting the coin operated feeding device F and the
movable dial or register E, so that the latter is rotated along with the coin operated
device when such moves forward, but can travel backwards independently (as the
gas passes through the meter) under the action of the ordinary index gearing of
the same, substantially as and for the purposes described.
2. In combination with the movable dial or register of an automatic prepayment
gas meter, a projection N moving with such dial and closing the valve of the
meter when the quantity of gas paid for has passed through, substantially as
described.
3. In automatic prepayment gas meters, a means for forming the coin connection,
consisting of a guide way such as K, in traversing which, the coin and its carrier
are depressed, and a pawl or pawls, which, on the depression of the coin and carrier,
are caused to engage the ratchet wheel F or its equivalent, being retained in
connection therewith by guides such as L', substantially as described.
4. In automatic prepayment gas meters, a device for regulating the quantity of
gas to be delivered, consisting of the projections and guiding device L L L
operating substantially as hereinbefore described and shown.
5. In automatic prepayment gas meters an improved device for automatically
closing the coin slot and so preventing the insertion of more than a predetermined
number of coius, consisting of a pin or bolt which may either form part of a lever
or arm or may be independent and is actuated in connection with the movable dial
or register and passes through the sides of the coin slot or through fixed guides in
connection with it, substantially as described.
Dated this 11th day of September 1893.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents.