Improvements in Prepayment Apparatus suitable for Gas and other Meters.
Year: 1897

page_text: Date of Application, 1st Nov., 1897
Complete Specification Left, 2nd Aug., 1898-Accepted, 1st Nov., 1898
TRUVIDIONAL DIUITIATION.
Improvements in Prepayment Apparatus suitable for Gas and other
Meters.
L, HAYDN THIES HARRISON, of 47, Victoria Street, Westminster, in the County
of London, Engineer, do hereby declare the nature of this invention to be as
follows;-
My invention has reference to improvements in prepayment apparatus suit-
able for use in connection with gas, electricity and other meters, intended to
supply a given quantity of gas, electricity or other fluid (hereinafter referred
to as gas) in exchange for each coin or token (hereinafter referred to as the
coin) inserted in the apparatus, and it relates more particularly to apparatus
so constructed that it is only necessary to insert a coin therein in order to obtain
its equivalent in gas, the turning of a handle, or the pulling of a knob or trigger,
or other operation at the time of inserting the coin being dispensed with.
According thereto in order to ensure that the apparatus for causing the
delivery of gas in exchange for a coin shall be operated to the same extent for
each coin inserted, whether the coin is gently pressed into the coin slot or shoot
or is suddenly forced into the same by a blow, the coin is caused by its periphery
to bear against and move idly to one side a lever (hereinafter called the coin
lever) which after the passage of the coin is caused to return under the action
of a weight or spring to its original position and in so doing actuate to a pre-
determined extent the apparatus for causing the delivery of gas to take place.
In connection with the coin lever there is or may be provided a locking device
adapted to be operated by the coin so as to unlock the coin lever and permit it
to be operated as described. To prevent the coin being fraudulently withdrawn
from the coin shoot after being used to operate the coin lever, there is provided
at a point between the free end of the lever and the outer end of the shoot,
a stop device which will move and permit a coin to enter but will prevent its
being pulled out again.
}
In one arrangement of mechanism of the kind referred to, the coin lever is
provided with a weighted arm and with a pin that projects into the coin shoot
through a slot in one of the walls thereof so as to be located near one side of the
slot. At the opposite side of the wall is a stop device in the form of a sliding
bolt that is formed with ratchet teeth and is normally pressed into the coin
shoot by a spring. In proximity to the bolt is a fixed rack having ratchet teeth
adapted to engage with and hold those on the bolt when the latter is pressed
toward them. The side of the coin shoot opposite to the pin on the coin lever
is formed partly by a strip of metal which is fixed upon a pin to one end of
which, outside the shoot, is fixed a lever arm having a notched part adapted to
engage with a pin on the coin lever and locks the same in its normal position.
The arrangement is such that upon inserting a coin into the shoot, it first
slightly depresses the bolt and moves it back against the action of its spring

page_text: which will return it or partly return it to its normal position after the coin or
the largest portion thereof has passed it. The coin upon being pressed between
the movable side of the shoot and the pin on the coin lever slightly tilts the
former and causes it to unlock the coin lever which, as the coin is pressed
further into the shoot, is moved idly to one side thereof. As the largest part of
the coin passes below the pin on the lever, the pin and lever return to their
normal position in which they are again locked, the lever during its return move-
ment forcing by its pin the coin into the coin receptacle and operating through
a pawl and ratchet wheel or equivalent means, the apparatus for causing the
delivery of gas. Should it be attempted to withdraw the. coin after it has been
used to operate the coin lever, it will move the toothed part of the sliding bolt
into contact with the fixed rack which will prevent the bolt being pressed side-
ways out of the shoot and thus prevent the coin from being withdrawn.
The apparatus operated from the coin lever for causing the delivery of gas
to take place may be of various kinds. According to one construction such
apparatus comprises two toothed wheels one of which (hereinafter called for ‹lis-
tinction the spur wheel) is arranged to be rotated from the meter train and the
other of which (hereinafter called for distinction the ratchet wheel) is arranged
to be rotated in one direction by the pawl on the coin lever, the two wheels
being provided on their opposing sides with crown or bevel wheels that are in
gear with an intermediate spur or bevel pinion carried by a radial arm, plate
or frame (hereinafter called for distinction the radial arm) arranged to rotate
between the spur and ratchet wheels. The arrangement is such that for each
coin of proper value inserted in the apparatus, the ratchet wheel will be turned
through a definite angle notwithstanding slight variations in the diameter of
different coins, and the radial arm will be turned a definite amount and by the
movement of the coin lever a valve, switch or equivalent device will be moved
against the action of a spring or weight into a position to enable gas, electric
current or other fluid to pass the meter until the spur wheel gradually returns
the radial arm into its original position and by releasing a pawl or other suitable
device causes the valve or equivalent to shut off the supply of gas or other fluid
or electricity when the amount paid for has been consumed.
The spur and ratchet wheels may be mounted to rotate independently of
each other on the same shaft, the pinion with which the crown or bevel wheels
gear, being mounted to rotate about a radial arm fixed to the shaft on which the
spur and ratchet wheel rotate. Thus the shaft rotates with the radial arm
which is moved by the pinion when it is carried round by the, crown wheels
and if a pointer be mounted on the end of the shaft it will be rotated a given
distance for every coin inserted. As the gas is consumed and causes the crown
wheel attached to the spur wheel to rotate in the opposite direction to that in
which the ratchet wheel was moved by the insertion of a coin, the pointer will
be gradually rotated towards its original position and will thus show the amount
of gas to the credit of the consumer at any time. The valve, which is preferably
a sliding plunger valve with coiled spring, is prevented, for the time being,
from returning to its closed position, by a detent which catches in a notch in
the valve when the same is opened by the coin lever, the lever which opened
the valve being nevertheless free to afterward move backward so that the coin
lever can be repeatedly operated by the insertion of additional; coins for the
purpose of rotating the ratchet wheel and radial arm to a greater extent.
The detent is connected to a pivoted arm or lever arranged to come in contact
.. with the radial arm on which the intermediate wheel or pinion rotates, the said
arm being arranged in such a manner that when it returns to the starting posi-
tion out of which it is moved by the insertion of a coin, it moves the detent
and releases the valve which is then moved into its closed position by the spring
or its equivalent.
The action of the apparatus is as follows:-
The ratchet wheel being geared by the crown or bevel wheel thereon to the

page_text: radial pinion, when it is partly rotated by the pawl of the coin lever it causes
the said pinion to rotate upon the crown or bevel wheel fast on the spur wheel,
which at this time is stationary or nearly so, thereby causing the radial arm,
on which the pinion is mounted, to turn through an angular distance equal to
one half that moved through by the ratchet wheel. The radial arm being then
moved out of contact with the detent which then holds open the valve, the valve
remains open. As gas or other fluid is allowed to flow through the meter the
spur wheel in gear with the meter train, and the crown or bevel wheel carried
thereby, will be gradually rotated and will through the pinion, which will
then travel on the crown or bevel wheel on the then stationary ratchet wheel,
rotate the radial arm in the opposite direction until it has been moved back
through an angular distance equal to that through which it was moved by the
ratchet wheel, whereupon the radial arm will assume its original or starting
position and will disengage the detent from the valve and permit the same to
be automatically closed so as to cut off the further supply of gas or other fluid
until another coin has been inserted in the apparatus.
The arrangement is such that coins can be successively inserted until the
radial arm has been caused to make nearly a complete revolution, and the
valve remaining open, gas or other fluid will be supplied until the spur wheel
has been rotated to the same extent as the ratchet wheel has been rotated by the
introduction of successive coins. The number of coins inserted will be indicated
by the pointer mounted on the shaft to which the radial arm is fixed, and as
this arm is moved back during consumption of the gas the pointer will indicate
the amount of gas paid for but not consumed.
In applying my apparatus to control an electricity meter the valve is replaced
by a switch. In this case if the registering train of the meter has very little
driving power the catch for holding the switch in the on position can be con-
trolled by an electro magnet which is caused to release the switch when a sniall
shunt current is sent through it upon the radial arm coming into electrical
contact with a platinum contact, or otherwise completing an electrical circuit
through it. But in most meters I find such a relay circuit unnecessary in
which case the switch is released by a detent as herein before described.
It has been found in practice that in order to obtain the most accurate results
the amount through which the measuring wheel is caused to travel by the inser-
tion of each coin must be made definite by means of a device which will bring
it to a definite position each time it is moved. Suitable means for this purpose
is a spring which is caused to press into notches equidistantly cut on the peri-
phery of the wheel.
In order to change the quantity of gas supplied for each coin inserted, the
distance through which the spur wheel of the differential gear hereinbefore
described is rotated by the meter for a given quantity of gas supplied, may be
varied, or the distance through which the ratchet wheel is rotated by the pawl
of the coin lever may be varied. The first can be done by changing the ratio
of the gearing between it and the meter but this is tedious and unsatisfactory.
The latter can be done by regulating the traverse of the pawl but this also is
not always satisfactory. I have therefore devised an arrangement by which
the quantity of gas supplied in exchange for a coin can be varied by simply
moving a lever or pawl. One arrangement for this purpose comprises a cam
which is fixed on one of the horizontal spindles of the meter train, or in the case
of a gas meter, on the driving spindle of the meter train. Below the cam and
arranged so as to come into contact with its underside is one arm of a lever
pivoted between the cam and the differential wheel which is required to be
rotated by the meter. Gearing into this wheel is a pinion mounted on the same
spindle as a finely cut ratchet wheel, and engaging with the teeth of this
ratchet wheel is a pawl mounted on the other arm of the said lever which is
moved up and down by the cam. The arrangement is such that when the cam
moves the lever in one direction, the pawl will rotate the ratchet wheel through

page_text: a distance corresponding to a given number of teeth depending on the angular
movement of the lever, and when the lever moves in the opposite direction,
which it does under the action of gravity or a spring, its pawl slips idly over a
given number. of teeth, the pawl again engaging the ratchet wheel and partly
rotating it when the lever is again operated in the reverse direction by the cam.
By regulating the angular movement imparted to the lever by the cam, the
amount the wheel is rotated can be regulated. This can be done by making
the end of the lever carrying the pawl rest against a stop the position of which
is capable of being varied so that the lever can be caused to come into contact
with the cam for a greater or less fraction of its revolution. For instance if
the lever touches the cam at its smallest and greatest radius respectively, the
greatest angular movement will be imparted to the lever, but if it only touches
the cam from its mean to its greater radius the angular movement of the lever
will be only one half the former movement. The adjustable stop can be arranged
to be moved by a radial arm at the opposite end of which is a dial which can
be marked with figures to indicate for each position of the radial arm the
quantity of gas, electricity or fluid that will be supplied in exchange for each
coin inserted in the apparatus.
It will be obvious that the details of construction can be variously modified
and that some of my improvements can be used without others, or with different
operating means. Thus the differential gearing hereinbefore described may be
used with coin actuated mechanism other than that herein set forth.
Dated this 1st day of Novemb.. 100-
COMPLETE SPECIFICATION.
Improvements in Prepayment Apparatus suitable for Gas and other
Meters.
I, HAYDN THIES HARRISON, formerly of 47, Victoria Street, Westminster, in the
County of London, but now of 19 and 21, Queen Victoria Street, in the City of
London, 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 has reference to improvements in prepayment apparatus suit-
able for use in connection with gas, electricity and other meters, intended to
supply a given quantity of gas, electricity or other fluid (hereinafter referred
to as gas) in exchange for each coin or token (hereinafter referred to as the
coin) inserted in the apparatus, and it relates more particularly to apparatus
so constructed that it is only necessary to insert a coin therein in order to obtain
its equivalent in gas, the turning of a handle, or the pulling of a knob or trigger,
or other operation at the time of inserting the coin being dispensed with.
According thereto in order to ensure that the apparatus for causing the
delivery of gas in exchange for a coin shall be operated to the same extent for
each coin inserted, whether the coin is gently pressed into the coin slot or shoot
or is suddenly forced into the same by a blow, the coin is caused by its periphery
to bear against and move idly to one side a lever (hereinafter called the coin
lever) which, after the passage of the coin, is caused to return under the action
of a weight or spring to its original position and, in so doing, to actuate to a
predetermined extent the apparatus for controlling the delivery of gas. In

page_text: connection with the coin lever there is or may be provided a locking device
adapted to be operated by the coin so as to unlock the coin lever and permit
it to be operated as described. To prevent the coin being fraudulently with-
drawn from the coin shoot after being used to operate the coin lever, there is
provided at a point between the free end of the lever and the outer end of the
shoot, a stop device which will move and permit a coin to enter but will prevent
its being pulled out again.
Referring to the accompanying drawings,
Fig. 1 is an elevation of one arrangement. of prepayment apparatus according
to this invention, applied to a gas meter.
Fig. 2 is a plan, part of the meter cover being removed; and
Figs. 3 and 4 are detail views hereinafter referred to.
1 is the casing of the apparatus formed with a coin slot or shoot 2, the walls
of which are recessed as shown so as to allow the coin 3 to be readily pressed
down into a money box below.
4 is the coin lever provided with a weighted arm 4ª and with a pin 4b that
projects into the coin shoot 2 through a slot 2 in one of the walls thereof so as
to be located near one side of the shoot. 5 is a sliding bolt that serves as a
stop device; it is formed with ratchet teeth and is normally pressed into the
coin shoot by a spring 6. In proximity to the bolt is a fixed rack 5 having
ratchet teeth adapted to engage with those on the bolt, when the latter is
pressed toward them. The side of the coin shoot opposite to the pin 4b of the
coin lever is formed partly by a strip of metal 7, which is fixed upon a pin 7,
to one end of which, outside the shoot, is fixed a lever arm 8 having a notched
part adapted to engage with a pin 9 on the coin lever and to lock the same in
its normal position. The arrangement is such that upon inserting a coin into
the shoot, it first slightly depresses the bolt 5 and moves it back against the
action of its spring 6, which will return it or partly return it to its normal
position after the coin or the largest portion thereof has passed it. The coin
upon being pressed between the movable side 7 of the shoot and the pin 4 on
the coin lever slightly tilts the former and causes it to raise the arm 8 and so
unlock the coin lever, which, as the coin is pressed further into the shoot, is
moved idly to one side thereof. As the largest part of the coin passes below
the pin 4 the coin lever returns to its normal position in which it is again
locked, the lever, during its return movement. forcing by its pin 4b the coin
into the coin receptacle, and operating the apparatus for controlling the delivery
of gas. Should it he attempted to withdraw the coin, after it has been used
to operate the coin lever, it will move the toothed part of the sliding bolt 5
into contact with the fixed rack 5" which cannot then be pressed sideways out
of the shoot and will thus prevent the coin from being withdrawn.
The apparatus operated from the coin lever for causing the delivery of gas
to take place may be of various kinds. According to the construction illus-
trated it comprises two toothed wheels, one 10 of which (hereinafter called for
distinction the spur wheel) is arranged to be rotated from the meter train and
the other 11 of which (hereinafter called for distinction the ratchet wheel) is
arranged to be rotated in one direction by the pawl 12 on the coin lever, the
two wheels being provided on their opposing sides with crown or bevel
wheels 10, 11 that are in gear with an intermediate spur or bevel pinion 13,
carried by a radial arm, plate or frame 14 (hereinafter called for distinction the
radial arm) arranged to rotate between the spur and ratchet wheels. The
arrangement is such that for each coin of proper value inserted in the apparatus,
the ratchet wheel 11 will be turned by the pawl of the coin lever through a
definite angle notwithstanding slight variations in the diameter of different
coins, and consequently the radial arm 14 will be turned a definite amount, and,
by the movement of the coin lever, the valve 15 of the meter will be opened.
In the arrangement illustrated the coin lever has connected with it an arm 16

page_text: which engages in a slot in the valve spindle and moves the valve against the
action of a spring or weight into a position to enable gas to pass through the
meter, until the spur wheel 10 gradually returns the radial arm 14 into its original
position.
The valve 15, which is preferably a sliding plunger valve with coiled spring
as shown in section in Fig. 4, is prevented, for the time being, from returning
to its closed position, by a counterweighted pawl or detent 17 which catches a
projection on the valve when the same is opened by the coin lever, which is
nevertheless free to afterward move backward so that it can be repeatedly
operated by the insertion of additional coins for the purpose of rotating the
ratchet wheel and radial arm to a greater extent.
The detent is connected to a pivoted arm or lever 18 with which the radial
arm 14 comes in contact so that the said arm 14, when it returns to the starting
position out of which it is moved by the insertion of a coin, moves the detent 17
and releases the valve, which is then moved into its closed position by the
spring or its equivalent. It is necessary to insert two coins before gas will be
delivered owing to the radial arm 14 not being actuated so as to allow the
detent 17 to move under the action of its weight into a position ready for
engagement with the valve until the coin lever makes its first return movement
which return movement also moves the arm 16 and releases the valve.
The spur wheel 10 and the ratchet wheel 11 may be mounted to rotate inde-
pendently of each other on the same shaft, the pinion 13 being mounted to
rotate about a radial arm fixed to the said shaft. Thus the shaft rotates with
the radial arm and, if a pointer 16* be mounted on the end of the shaft, it will
be rotated a given distance for every coin inserted. As the gas is consumed
and causes the crown wheel attached to the spur wheel to rotate in the opposite
direction to that in which the ratchet wheel was moved by the insertion of a
coin, the pointer will be gradually rotated towards its original position and will
thus show the amount of gas to the credit of the consumer at any time.
The action of the apparatus is as follows:-
The ratchet wheel 11 being geared by the crown or bevel wheel 11 to the
radial pinion 13, when it is partly rotated by the pawl 12 causes the said pinion
to rotate or roll upon the crown or bevel wheel 10, which at this time is
stationary or nearly so, thereby turning the radial arm 14 through an angular
distance equal to one half that moved through by the ratchet wheel. The radial
arm being then moved out of contact with the arm or lever 18 the valve will
be held open by the detent 17. As gas is allowed to flow through the meter the
spur wheel 10 and the crown or bevel wheel 10" will be gradually rotated pre-
ferably by means hereinafter described and will through the pinion 13, which
will then travel on the crown or bevel wheel 11" on the then stationary ratchet
wheel 11, rotate the radial arm 14 in the opposite direction until it has been
moved back through an angular distance equal to that through which it was
moved by the ratchet wheel, whereupon the radial arm will disengage the
detent 17 from the valve and permit the same to be automatically closed so as
to cut off the further supply of gas until another coin has been inserted in the
apparatus. With such an arrangement coins can be successively inserted until
the radial arm has been caused to make nearly a complete revolution, and the
valve will remain open and gas will be supplied until the spur wheel has been
rotated to the same extent as the ratchet wheel has been rotated by the intro-
duction of several coins. The number of coins inserted will be indicated by
the pointer 16* and as the arm 14 is moved back during consumption of the
gas the pointer will indicate the amount of gas paid for but not consumed.
It has been found in practice that in order to obtain the most accurate results,
the amount through which the ratchet wheel 11 is caused to travel by the
insertion of each coin must be made definite by means of a device which will
bring it to a definite position each time it is moved. Suitable means for this

page_text: purpose is a spring 20 which is caused to press into the spaces between the
teeth of the ratchet wheel or into other notches equidistantly cut on the periphery
of the wheel.
:
In order to change the quantity of gas supplied for each coin inserted, the
distance through which the spur wheel 10 of the differential gear. hereinbefore
described is rotated by the meter for a given quantity of gas supplied, may be
varied, or the distance through which the ratchet wheel is rotated by the pawl
of the coin lever may be varied. The first can be done by changing the ratio
of the gearing between it and the meter but this is tedious and unsatisfactory.
The latter can be done by regulating the traverse of the pawl but this also is
not always satisfactory.
I
".
The arrangement by which the quantity of gas supplied in exchange for a
coin can be varied comprises a cam 21 which is fixed on the driving spindle of the
meter train. Below the cam 21 is one arm of a lever 22 pivoted at 23 between
the cam and the wheel 10 which is required to be rotated by the meter. Gearing
into the wheel 10 is a pinion 24 mounted on the same spindle as a finely cut
ratchet wheel 25; engaging with the teeth of this ratchet wheel is a pawl 26
that is mounted on the other arm of the lever 22 which is oscillated or moved
up and down by the cam in such a way that, when the cam moves the lever in
one direction, the pawl will rotate the ratchet wheel through a distance corre-
sponding to a given number of teeth depending on the angular movement of
the lever, and when the lever moves in the opposite direction, which it does
under the action of gravity or a spring, its pawl slips idly over a given number
of teeth, the pawl again engaging the ratchet wheel and partly rotating it when
the lever is again operated in the reverse direction by the cam. By regulating
the angular movement imparted to the lever by the cam, the extent of rotation
of the wheel can be regulated. This can be done by making the end of the
lever carrying the pawl rest against a stop 27 the position of which is capable
of being varied so that the lever will be in contact with the cam for a greater
or less fraction of its revolution. For instance, if the lever touches the cam
at both its smallest and greatest radius, the greatest angular movement will be
imparted to the lever, but if it only touches the cam from its mean to its greater
radius the angular movement of the lever will be only one half the former
movement. The adjustable stop 27 can be arranged to be moved by a radial
arm at the opposite end of. which is a dial, which can be marked with figures
to indicate, for each position of the radial arm the quantity of gas, electricity
or fluid that will be supplied in exchange for each coin inserted in the apparatus.
Fig. 1 is a diagrammatic view of an arrangement of this kind. The stop. 27
is pivoted at 27 to the casing and its other end is supported by a pin 27b carried
by a pivoted arm 27°; attached to the pivot of this arm is a pointer 27 that
moves in front of a dial on the outside of the casing. The arm 27° is held, in
position by a spring detent that takes into a toothed quadrant 27. Fig. 5
illustrates in sectional elevation a modified construction of prepayment mechan-
ism. In this case the valve 15 is, normally kept closed by means of an arm 14*
bearing against a projection on the valve, the spring 15ª being thereby. com-
pressed. On the insertion of a coin into the coin shoot, a pin 7b fixed to an
arm 7 connected to the lever arm 8 is moved aside thereby raising the arm 8.and
so unlocking the coin lever. On the further insertion of the coin the coin lever 4
is idly moved back, and on its return rotates the ratchet wheel 11 (not shown)
by means of the pawl 12. The rotation of the ratchet wheel 11 moves the
arm 14 which is attached to the same spindle as the radial arm 14 (not shown)
away from the projection on the valve, and so allows the spring 15 to force it
open. After the consumption of the amount of gas that has been paid for,
the spur wheel 10, which is geared to the meter train by means of change wheels
5 located on the exterior of the meter casing, and covered by a glass plate
that covers the meter dials, moves the radial arm 14 (not shown) in the reverse
direction, and consequently the arm 14* against the projection on the valve
.

page_text: thereby compressing the spring and shutting of the gas supply. With this
arrangement the levers connecting the coin lever to the gas valve and those
for releasing the said valve when the proper quantity of gas is consumed can
be dispensed with and a gradual cutting off of the gas supply is obtained.
In applying my apparatus to control an electricity meter the valve is replaced
by a switch. In this case if the registering train of the meter has very little
driving power the catch for holding the switch in the on position can be con-
trolled by an electro magnet which is caused to release the switch when a small
shunt current is sent through it upon the radial arm coming into electrical
contact with a platinum contact, or otherwise completing an electrical circuit
through it. But in most meters I find such a relay circuit unnecessary in which
case the switch is released by a detent as hereinbefore described.
It will be obvious that the details of construction can be variously modified
and that some of my improvements can be used without others, or with different
operating means. Thus the differential gearing hereinbefore described may be
used with coin actuated mechanism other than that herein set forth.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
1. Prepayment apparatus for use in connection with gas and other meters
in which the periphery of the coin is caused by the act of insertion into the
coin shoot to bear against and move idly to one side a lever which, after the
passage of the coin, is returned by the action of a weight or spring to its original
position and thereby caused to actuate to a predetermined extent that part of
the apparatus whereby the delivery of gas or other fluid is controlled, substan-
tially as described.
2. In prepayment apparatus for use in connection with gas and other meters
the combination, with the coin actuated lever, of a locking device, such as a
strip of metal pivoted in the coin shoot and connected with a notched lever arm
that normally engages the coin lever, said device being adapted to be operated
by the coin during its passage through the coin shoot and prior to its contact
with the coin lever, substantially as described.
3. In prepayment apparatus for use in connection with gas and other meters
the provision, in the coin shoot between the free end of the coin lever and the
outer end of the coin shoot, of a stop device, such as a sliding spring pressed
bolt with ratchet teeth adapted to be caused to engage with a fixed rack only
when an attempt is made to withdraw a coin that has once displaced and passed
it, substantially as and for the purpose specified.
4. In prepayment apparatus for use in connection with gas and other meters
the combination with the coin lever, of a pawl carried by said lever, a ratchet
wheel adapted to be driven thereby, a wheel geared to the meter train and by
means of a pinion to the ratchet wheel, said pinion being carried by a radial arm
arranged between the said wheels, the arrangement being such that, for each coin
inserted, the ratchet wheel and the radial arm will be turned through definite
angles and gas or other fluid allowed to pass through the meter until a prede-
termined quantity has passed and the meter train has in consequence driven the
other wheel in the reverse direction to such an extent that the pinion and radial
arm will have been returned to their normal positions and the supply cut off,
substantially as described.
5. In prepayment apparatus of the kind referred to, means whereby the quan-
tity of gas or other fluid supplied per coin may be varied, comprising a cam on
a spindle of the meter train adapted to come in contact, as it rotates, with a lever
carrying a pawl that engages with a ratchet wheel connected with or geared
to the differential wheel that is to be driven from the meter, the angular move-
ment or throw of said lever being adjustable, substantially as described.
6. Prepayment apparatus for gas and other fluid meters constructed arranged

page_text: and operating substantially as described with reference to and shown in Figs. 1
to 4 inclusive of the accompanying drawings, or modified as described with refer-
ence to and shown in Fig. 5 thereof.
For the Applicant,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.