Note: Descriptions are shown in the official language in which they were submitted.
COUNTER MODULE ADAPTOR ASSEMBLY FOR ROTARY GAS METERS
FIELD
[0001] This disclosure relates generally to gas meter equipment, and
more
specifically to an adaptor assembly for rotary gas meters.
INTRODUCTION
[0002] Gas meters may be used to measure volumes of gas transported
and/or
used for heating or cooling purposes. For large-scale and/or industrial uses,
most gases
are typically sold on a price-per-volume basis (e.g. $5 per 1,000 cubic feet).
Accordingly, it is generally considered desirable to measure gases being
transported
and/or used with a relatively high degree of accuracy. For example, natural
gas may be
characterized as a relatively expensive commodity, and it is important to
accurately
measure the amount of gas being transported and/or consumed, particularly at
high
volume rates. Accurate measurement may prevent a consumer from being
overcharged
by a provider, and it may also ensure that the consumer is charged for the
entire volume
of gas provided.
[0003] A common method of providing accurate measurement of a
consumed
gas is the use of one or more positive displacement rotary gas meters. When
gas flows
through such a rotary gas meter, fixed volumes of gas are displaced by, for
example,
two figure-eight impellers that rotate in opposite directions within a
cylinder of known
volume. The impellers of the gas meter rotate because of a lower differential
pressure at
the outlet of the meter than is present at the inlet. As they rotate, a fixed
volume of gas
or other fluid is entrapped and then moved toward the outlet. Therefore, with
each full
rotation of the impellers, a known volume of gas or other fluid is displaced
through the
outlet.
[0004] By measuring the number of rotations of the impellers, the volume of
gas
or other fluid displaced over a period of time can be determined. Also, as the
lobed
figure-eight impellers remain in a fixed relative position, it is only
necessary to measure
the rotational movement of one of the impellers. To accomplish this, in the
case of
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positive displacement rotary gas meters that are electronically compensated,
the
impeller may be magnetically coupled to an electronic recording device.
[0005] Typically, a magnetic coupling device senses movement of the
impellers
by sensing the passage of magnets fixed to the rotating impellers. This may be
done
with a Wiegand sensor mounted outside the pressure body of the gas meter. The
sensor then transfers a signal to the electronic recording device. This
electronic device
compensates for density changes due to fluctuations in the temperature,
pressure,
and/or composition of the gas being metered, resulting in an extremely
accurate
measurement of the consumed gas.
[0006] However, electronically compensated gas meters may fail to correctly
record the amount of gas volume passing through it for a variety of reasons.
The most
common failures are due to power loss, faulty electronic components, failures
due to
lightning, or vandalism. If the electronic module stops recording for any
reason, there is
a need for a device to account for the flow. It is thought that hundreds of
millions, if not
billions, of dollars are contested in disputes each year between gas providers
and
consumers as a result of failures of electronically compensated gas meters.
SUMMARY
[0007] The following introduction is provided to introduce the reader
to the more
detailed discussion to follow. The introduction is not intended to limit or
define any
claimed or as yet unclaimed invention. One or more inventions may reside in
any
combination or sub-combination of the elements or process steps disclosed in
any part
of this document including its claims and figures.
[0008] Alternatively, or additionally, to an electronic recording
device, a gas meter
impeller may be coupled to a mechanical register, either directly or through a
series of
reduction gears. A mechanical register or counter can conveniently account for
the flow
in the event of a failure of an electronically compensated gas meter.
Typically, such
mechanical registers display the unconverted volume of consumed gas (e.g. the
volume
of gas that passed through the gas meter body, without compensating for
density
changes due to fluctuations in the temperature, pressure, and/or composition
of the gas
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being metered). This volume displayed by a mechanical register may be used to
determine the amount of gas that has flowed through the pressure body. Where a
gas
meter body is provided with electronic recording device and a mechanical
register, the
mechanical register may act as a backup to the electronic recording device.
[0009] Typical mechanical registers have a complicated gear assembly that
is
mechanically actuated by the rotation of the impellers of the gas meter. That
is, gas
flowing through the meter causes rotation of the impeller of the gas meter,
the impeller
drives a first gear member in a series of gear members, and the gear members
in turn
drive the uncorrected volume register.
[0010] A manufacturer of gas meter bodies may provide a common electronic
counter module mounting surface on a number of models and/or sizes of gas
meter
bodies to which an electronic counter module may be coupled. However, based on
the
relative location of the impeller within the gas meter body, the location of
the impeller
(and/or a counter drive shaft operatively coupled to the impeller) relative to
the mounting
surface may be different for different models and/or sizes of gas meter
bodies.
[0011] While a typical electronic counter module may be used with gas
meter
bodies having different relative locations of their common mounting surface
and counter
drive shafts (as the magnetic sensor, typically being connected to the
electronic counter
module by flexible wiring, may be easily repositioned relative to the mounting
surface),
the differing relative positions of counter drive shafts may present problems
for the use
of a mechanical counter with different sizes and/or models of gas meter
bodies. This
may require the use of a different mechanical counter module and/or a
different housing
with each different model and/or size of gas meter body.
[0012] The apparatus and backup counter module disclosed herein may
alternatively be used with gas meter bodies having different relative
positioning of their
counter drive shaft and mounting surface. The ability to use this universal
apparatus
and backup counter module with multiple gas meter bodies provides a number of
advantages. For example, the number of different mechanical counter modules
and/or
housings that are required to be brought to a customer's facility when
installing and/or
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repairing backup counter modules may be reduced, as the same parts may be used
with a wide variety of gas meters.
[0013] In accordance with a first broad aspect, there is provided an
apparatus for
use with a backup counter module, the apparatus comprising: a housing having a
first
end and a second end, the first end for coupling the housing to a gas meter
body, the
second end for coupling an electronic counter module to the housing; and the
second
end having an inner surface and an outer surface, the inner surface having at
least two
sets of backup counter module engagement features for securing an output end
of a
backup counter module in one of at least two backup counter module positions;
whereby the housing may be coupled to a first gas meter body with a first
backup
counter module positioned within the housing with an input end of the first
backup
counter module coupled to a counter drive shaft of the first gas meter body
and an
output end of the first backup counter module secured in one of the at least
two backup
counter module positions, and whereby the housing may alternatively be coupled
to a
second gas meter body with the first backup counter module positioned within
the
housing with the input end of the first backup counter module coupled to a
counter drive
shaft of the second gas meter body and the output end of the first backup
counter
module secured in another of the at least two backup counter module positions.
[0014] In some embodiments, the outer surface of the housing is
adapted to
receive a magnetic sensor operatively coupled to an electronic counter module
in one of
at least two magnetic sensor positions.
[0015] In some embodiments, the outer surface of the housing
comprises at least
two apertures, each aperture for receiving a magnetic sensor therein.
[0016] In some embodiments, the outer surface of the housing
comprises an
aperture shaped so that a magnetic sensor can be secured in one of at least
two
magnetic sensor positions within the aperture.
[0017] In some embodiments, each of the at least two sets of backup
counter
module engagement features comprise at least one recess for receiving a
complimentary protrusion extending from an output end of a backup counter
module.
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[0018] In some embodiments, the second end of the housing further
comprises a
bore through which wiring associated with a temperature probe coupled to an
electronic
counter module may be run.
[0019] In some embodiments, the housing further comprises a conduit
extending
from the bore through which wiring associated with a temperature probe coupled
to an
electronic counter module.
[0020] In some embodiments, the at least two sets of backup counter
module
engagement features comprises three sets of engagement features, whereby an
output
end of a backup counter module may be secured in one of at least three backup
counter
module positions.
[0021] In some embodiments, the housing has at least one viewing
window
positioned such that when a backup counter module is secured in one of the at
least
two backup counter module positions and the housing is coupled to a gas meter
body, a
counter display of the backup counter module is visible through the viewing
window.
[0022] In some embodiments, at least a portion of the housing is
translucent.
[0023] In some embodiments, at least a portion of the housing is
transparent.
[0024] In some embodiments, the first gas meter body comprises a gas
meter
body of a first size, and wherein the second gas meter body comprises a gas
meter
body of a second size.
[0025] In accordance with another broad aspect, there is provided a backup
counter module having an input end and an output end, the backup counter
module
comprising: a frame; a driven shaft mounted to the frame and having an end for
coupling to a counter drive shaft of a gas meter body, the driven shaft end
located at the
input end of the backup counter module; a mechanical counter mounted to the
frame
and coupled to the driven shaft so that rotation of the driven shaft
increments a value of
the mechanical counter proportionally to the rotation of the driven shaft; an
output shaft
connected to the driven shaft through a gear train so that rotation of the
driven shaft
results in a proportional rotation of the output shaft, the output shaft
having a mount for
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receiving a magnet so that the magnet rotates in direct proportion to rotation
of the
output shaft, the mount located at the output end of the backup counter
module; and
one or more housing engagement features at the output end of the backup
counter
module for securing the output end of the backup counter module in one of at
least two
backup counter module positions within a housing.
[0026] In some embodiments, the one or more housing engagement
features
comprise at least one protrusion for insertion into a complimentary recess on
a housing.
[0027] In some embodiments, the magnet comprises a magnet for use
with a
Wiegand sensor.
[0028] In some embodiments, a longitudinal axis of the driven shaft and a
longitudinal axis of the output shaft are offset.
[0029] In some embodiments, the frame comprises a frame base and two
frame
plates extending from the frame base, and wherein the driven shaft extends
through
one of the two frame plates and is connected to the other of the two frame
plates via a
bearing.
[0030] In some embodiments, the gear train is configured such that
the output
shaft rotates at the same speed as the driven shaft.
[0031] It will be appreciated by a person skilled in the art that a
method or
apparatus disclosed herein may embody any one or more of the features
contained
herein and that the features may be used in any particular combination or sub-
combination.
[0032] These and other aspects and features of various embodiments
will be
described in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] For a better understanding of the described embodiments and to show
more clearly how they may be carried into effect, reference will now be made,
by way of
example, to the accompanying drawings in which:
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[0034] FIG. 1 is a perspective view of an electronic counter module
and a first
gas meter body;
[0035] FIG. 2 is a partially exploded view of the electronic counter
module and
gas meter body of FIG. 1 with an embodiment of an apparatus and backup counter
module positioned between the electronic counter module and the gas meter
body;
[0036] FIG. 3 is a perspective view of the electronic counter module,
apparatus
and backup counter module, and gas meter body of FIG. 2;
[0037] FIG. 4 is a side view of the electronic counter module,
apparatus and
backup counter module, and gas meter body of FIG. 2;
[0038] FIG. 5 is a perspective view of one end of an apparatus for use with
a
backup counter module 200;
[0039] FIG. 6 is a perspective view of another end of the apparatus
of FIG. 5;
[0040] FIG. 7A is another end view of the apparatus of FIG. 5 with a
backup
counter module secured in a first backup counter module position;
[0041] FIG. 7B is an end view of the apparatus of FIG. 5 with a backup
counter
module secured in a second backup counter module position;
[0042] FIG. 7C is an end view of the apparatus of FIG. 5 with a
backup counter
module secured in a third backup counter module position;
[0043] FIG. 8 is a perspective view of an embodiment of a backup
counter
module;
[0044] FIG. 9 is another perspective view of the backup counter
module of FIG.
8;
[0045] FIG. 10 is another perspective view of the backup counter
module of FIG.
8;
[0046] FIG. 11 is an exploded view of the backup counter module of FIG. 8;
[0047] FIG. 12 is another exploded view of the backup counter module
of FIG. 8;
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[0048] FIG. 13 is an end view of the apparatus of FIG. 5 with a
backup counter
module secured in a first backup counter module position;
[0049] FIG. 14 is a perspective view of the apparatus of FIG. 5 with
a backup
counter module secured in a first backup counter module position;
[0050] FIG. 15 is a side view of the apparatus of FIG. 5 with a backup
counter
module secured in a first backup counter module position;
[0051] FIG. 16 is an end view of the apparatus of FIG. 5 with a
backup counter
module secured in a second backup counter module position;
[0052] FIG. 17 is a perspective view of the apparatus of FIG. 5 with
a backup
counter module secured in a second backup counter module position;
[0053] FIG. 18 is a side view of the apparatus of FIG. 5 with a
backup counter
module secured in a second backup counter module position;
[0054] FIG. 19 is a partially exploded view of an electronic counter
module, a
second gas meter body, and the apparatus and backup counter module of FIG. 16
positioned between the electronic counter module and the gas meter body;
[0055] FIG. 20 is a perspective view of the electronic counter
module, apparatus
and backup counter module, and gas meter body of FIG. 19;
[0056] FIG. 21 is a side view of the electronic counter module,
apparatus and
backup counter module, and gas meter body of FIG. 19;
[0057] FIG. 22 is an end view of the apparatus of FIG. 5 with a backup
counter
module secured in a third backup counter module position;
[0058] FIG. 23 is a perspective view of the apparatus of FIG. 5 with
a backup
counter module secured in a third backup counter module position;
[0059] FIG. 24 is a side view of the apparatus of FIG. 5 with a
backup counter
module secured in a third backup counter module position;
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[0060] FIG. 25 is a partially exploded view of an electronic
counter module, a
third gas meter body, and the apparatus and backup counter module of FIG. 22
positioned between the electronic counter module and the gas meter body;
[0061] FIG. 26 is a perspective view of the electronic counter
module, apparatus
and backup counter module, and gas meter body of FIG. 25; and
[0062] FIG. 27 is a side view of the electronic counter module,
apparatus and
backup counter module, and gas meter body of FIG. 25.
[0063] It will be appreciated that FIGS. 10 and 11 are for
reference only, and that
it may not be possible to assemble and/or disassemble the backup counter
module with
the components in their illustrated configurations.
[0064] The drawings included herewith are for illustrating
various examples of
articles, methods, and apparatuses of the teaching of the present
specification and are
not intended to limit the scope of what is taught in any way.
DESCRIPTION OF EXAMPLE EMBODIMENTS
[0065] Various apparatuses, methods and compositions are described below to
provide an example of an embodiment of each claimed invention. No embodiment
described below limits any claimed invention and any claimed invention may
cover
apparatuses and methods that differ from those described below. The claimed
inventions are not limited to apparatuses, methods and compositions having all
of the
features of any one apparatus, method or composition described below or to
features
common to multiple or all of the apparatuses, methods or compositions
described
below. It is possible that an apparatus, method or composition described below
is not an
embodiment of any claimed invention. Any invention disclosed in an apparatus,
method
or composition described below that is not claimed in this document may be the
subject
matter of another protective instrument, for example, a continuing patent
application,
and the applicant(s), inventor(s) and/or owner(s) do not intend to abandon,
disclaim, or
dedicate to the public any such invention by its disclosure in this document.
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1
[0066] While the apparatus and methods disclosed herein are described
specifically in relation to conventional positive displacement rotary gas
meters, it will be
appreciated that the apparatus and methods may alternatively be used with
other types
of gas meters.
[0067] FIG. 1 illustrates a positive displacement rotary gas meter and an
electronic counter module. Gas meter body 10A has an aperture 16 for providing
access to a counter drive shaft of the gas meter, and an aperture 14 for
receiving a
temperature probe. As used herein, a counter drive shaft is any shaft of the
gas meter
body that rotates proportionally to the rotation of the impellers (e.g. lobed
figure-eight
impellers, or other rotors) and may be used to drive a counter module. For
example, a
rotor shaft may be used as a counter drive shaft. Gas meter body 10A also has
a
mounting surface 12 to which an electronic counter module 20 may be secured.
[0068] Electronic counter module 20 has a magnetic sensor 22 that may
be
positioned within aperture 16 of gas meter body 10A for sensing the rotation
of the
counter drive shaft. A display 24 is provided on electronic counter module 20
for
outputting the measured amount of gas that has traveled through the gas meter.
Electronic counter module 20 may also have a temperature probe (not shown) for
insertion into aperture 14, allowing electronic counter module 20 to provide a
temperature-corrected measurement of the volume of gas that has flowed through
the
gas meter, as is conventionally known.
[0069] For example, electronic counter module 20 may be an AdEMTm
series
electronic counter module as available from Romet Limited.
[0070] It will be appreciated that electronic counter module 20 may
be coupled
directly to gas meter body 10A, and used to measure a volume of gas that has
flowed
through the gas meter. But electronic counter module 20 may fail to correctly
record the
amount of gas volume passing through it for a variety of reasons. The most
common
failures are due to power loss, faulty electronic components, failures due to
lightning, or
vandalism. To account for a flow of gas without relying on electronic counter
module 20,
a mechanical counter module may also be coupled to gas meter body 10A.
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[0071] FIGS. 2-4 illustrate an apparatus for positioning a backup
counter module
(e.g. a mechanical counter module) between a gas meter body and electronic
counter
module. More specifically, a first end 112 of a housing 110 of the apparatus
100 is
configured to be coupled to the mounting surface 12 of gas meter body 10A, and
a
second end 114 of housing 100 is configured to be coupled to electronic
counter
module 20. As will be discussed further below, backup counter module 200 is
positioned
within housing 110 such that an input end of backup counter module 200 may be
coupled to the counter drive shaft of gas meter body 10A, and an output end of
backup
counter module 200 is secured to an inner surface of the second end 114 of
housing
110. In this way, when electronic counter module 20 is coupled to the second
end 114
of housing 110, magnetic sensor 22 may be used to sense the rotation of an
output
shaft of backup counter module 200. Since rotation of the output shaft of
backup
counter module 200 is proportional to (or equal to, depending on the gearing
of backup
counter module 200) the rotation of the counter drive shaft of the gas meter,
electronic
counter module 20 may use magnetic sensor 22 to indirectly sense the rotation
of the
counter drive shaft of the gas meter.
[0072] As exemplified in FIGS. 5 and 6, apparatus 100 comprises a
housing 110
having a first end 112 and a second end 114. First end 112 is configured to be
coupled
to the mounting surface 12 of a gas meter body 10. As shown, first end 112 has
an
annular flange 111 with a plurality of holes 113 for receiving mechanical
fasteners used
to secure housing 110 to gas meter body 10. It will be appreciated that first
end 112 of
housing 110 may be alternatively or additionally coupled to mounting surface
12 of a
gas meter body 10 by any suitable means, for example, using a magnetic
coupling
system.
[0073] As best seen in FIG. 5, the outer surface 118 of second end 114 is
adapted such that an electronic counter module 20 may be coupled to second end
114.
For example, outer surface 118 may be provided with a ridge 117 dimensioned so
that
ridge 117 and a complementary surface feature on electronic counter module 20
may
be placed in abutting relation with each other. It will be appreciated that
one or more
other surface features may be provided, or no such surface feature may be
provided.
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Alternatively or additionally, second end 114 may be provided with one or more
holes
119 for receiving mechanical fasteners used to secure electronic counter
module 20 to
housing 110. It will be appreciated that electronic counter module 20 may be
alternatively or additionally secured to second end 114 by any suitable means,
for
example, using a magnetic coupling system.
[0074] Second end 114 of housing 110 may also be adapted to receive
magnetic
sensor 22 of electronic counter module 20 in one or more magnetic sensor
positions.
For example, second end 114 has a circular aperture 142 dimensioned to receive
magnetic sensor 22 therein. Second end 114 also has a peanut-shaped aperture
144
dimensioned to receive magnetic sensor 22 in one of two positions (e.g. in
either lobe
144a or 144b of the peanut-shaped aperture). It will be appreciated that other
shapes
and/or sizes of apertures may be provided, depending for example on the
dimensions of
the magnetic sensor being used.
[0075] A bore 150 may optionally be provided in second end 114 to
allow a
temperature probe and/or associated wiring of electronic counter module 20 to
be
inserted therethrough, for insertion into aperture 14 of gas meter body 10.
[0076] Turning to FIG. 6, inner surface 116 of second end 114 is
adapted such
that a backup counter module may be alternatively secured in one of a
plurality of
backup counter module positions. In the illustrated embodiment, a first set of
engagement features 120a, 126a each have a corresponding recess 122a, 128a,
and
each recess 122a, 128a is dimensioned to receive a complimentary protrusion
extending from an output end of backup counter module 200. Thus, backup
counter
module 200 may be secured in a first backup counter module position 130a (see
e.g.
FIG. 7A) by positioning the complementary protrusions within the recesses
122a, 128a.
[0077] It will be appreciated that securing backup counter module 200 in
the first
backup counter module position 130a aligns the output end of backup counter
module
200 in a predetermined position relative to the second end 114 of housing 110.
Also, an
input end of backup counter module 200 will be aligned in a predetermined
position
relative to the first end 112 of housing 110.
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[0078] In a similar manner, a second set of engagement features 120b,
126b
allow an output end of backup counter module 200 to be secured in a second
backup
counter module position 130b (see e.g. FIG. 7B), and a third set of engagement
features 120c, 126c allow an output end of backup counter module 200 to be
secured in
a third backup counter module position 130c (see e.g. FIG. 7C).
[0079] Optionally, one or more visual aids 129a-c may be provided on
inner
surface 116 to assist in positioning backup counter module 200 for insertion
into
engagement features 120a-c, 126a-c.
[0080] Returning to FIG. 6, a conduit 152 may optionally be provided
between
bore 150 and first end 112 of housing 110 to guide and/or protect wiring
associated with
a temperature probe of electronic counter module 20.
[0081] A viewing window 160 may optionally be provided in housing 110
so that a
display of a backup counter is visible when housing 110 and backup counter
module
200 are installed on a gas meter body and electronic counter module.
[0082] It will be appreciated that housing 110 may be made of any suitable
rigid
material, such as metal, plastic, and the like. Optionally, some or all of
housing 110 may
be made of a material that is translucent or transparent. For example, viewing
window
160 may be made of a translucent or transparent material.
[0083] FIGS. 8-12 illustrate a backup counter module (e.g. a
mechanical counter
module) for use with apparatus 100. Backup counter module 200 has an input end
202
for coupling to a counter drive shaft of a gas meter body, an output end 204
for securing
the backup counter module to the housing 110. Backup counter module 200
includes a
mechanical counter 230 for tracking a number proportional to the number of
rotations of
the counter drive shaft.
[0084] An advantage of the backup counter module disclosed herein is that,
in
general, the more complicated the gear train, the more difficult it is to
ensure proper
measurement of low gas flow rates. By using a gear train with minimal
components, the
friction in the gear train is reduced and the energy needed to move the gear
train and
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counter is reduced. With a more complicated gear train, a significant
proportion of the
energy embodied in the gas flow is used to overcome the torque created by the
gear
train and counter. This may create errors in measuring low flow rates and
should be
avoided. Also, a simple gear train produces a minimal pressure drop which in
turn
allows the impellers of the gas meter to rotate in a normal manner. This may
increase
the accurately of the measurement of relatively low gas flow rates.
[0085] In the embodiment illustrated in FIG. 8, backup counter module
200
includes a frame 210 having a frame base 210 and two frame plates 212, 214 for
rotatingly supporting a driven shaft 220 and an output shaft 240. In the
illustrated
embodiment, bearings 260 are provided to facilitate rotation of the driven and
output
shafts relative to frame 10, although it will be appreciated that other
arrangements (e.g.
using one or more bushings) may alternatively or additionally be used.
[0086] Driven shaft 220 has an end 202 configured to be coupled to a
counter
drive shaft of a gas meter body, so that the driven shaft 220 rotates at a
rate
proportional to, and preferably at the same rate as, the counter drive shaft.
In the
illustrated embodiment, a magnet 222 is provided at the end of driven shaft
220. This
magnet 222 may be magnetically coupled to a rotor shaft of a gas meter body.
It will be
appreciated that driven shaft 220 may alternatively or additionally be coupled
to a
counter drive shaft using any suitable means.
[0087] A worm 224 is mounted on driven shaft 220 for meshing with a worm
gear
234, which in turn drives mechanical counter 230. In this way, when the
counter drive
shaft is rotated (e.g. in response to gas flowing through gas meter body 10),
mechanical
counter 230 is operable to count a number directly proportional to the number
of
rotations of counter drive shaft. This number is displayed on a display 232 of
mechanical counter 230.
[0088] While it is preferable to use a worm 224 and worm gear 234 so
that the
mechanical counter records a fraction of the number of rotations of the driven
shaft
(and, by extension, of the counter drive shaft), it will be appreciated that
any suitable
gearing may be used. For example, the gearing may be configured so that the
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mechanical counter 230 records the number of rotations of the counter drive
shaft on a
1:1 basis, or records a multiple of the number of rotations of the driven
shaft.
[0089] Mechanical counter 230 is illustrated as being mounted to the
frame base
210, although it will be appreciated that mechanical counter 230 may
alternatively, or
additionally, be mounted to one or both frame plates 212, 214.
[0090] Also notable in the arrangement shown is that the mechanical
counter 230
and its display 232 are oriented transverse to driven shaft 220 and output
shaft 240.
Such an arrangement may have a number of advantages. For example, rotating
mechanical counter 230 may reduce the overall size of backup counter module
200,
and in particular the length of the backup counter module 200 between the
first end 202
and second end 204 may be shorter than may be required if the mechanical
counter
were positioned parallel to driven shaft 220 and output shaft 240.
[0091] Also, as will be discussed further below, orienting display
232 transverse
to driven shaft 220 and output shaft 240 may allow a smaller viewing window
160 to be
provided in housing 110 while still allowing display 232 to be visible through
viewing
window 160 when backup counter module 200 is secured in any one of multiple
backup
counter module positions 130a-c.
[0092] It will be appreciated that that the value appearing on the
display 232 of
mechanical counter 230 may be manipulated in a variety of ways to determine
the
amount of gas consumed (e.g. flowed through the gas meter body) over a period
of
time. For example, a conversion factor based on the type of gas meter being
tracked
(e.g. by part or make number) may be used. For example, a suitable conversion
factor
may be determined by calculating the specific displacement generated by each
type (or
size) of gas meter. Such a conversion factor may be proportional to the size
of the gas
meter and the gear ratio between the impeller shaft of the gas meter and the
mechanical counter 230.
[0093] It will also be appreciated that, in addition to acting as a
backup for
electronic counter module 20, mechanical counter 230 may be used to track a
total
number of rotations of the counter drive shaft (and thus of the gas meter's
impeller) over
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the life of the gas meter. This may be valuable, as typically it is difficult
to measure the
life of a gas meter. Since mechanical counter 232 may be operable to count
throughout
the operational life of the gas meter, the value displayed on the display 232
may be
used as a proxy for the operational age of the gas meter, e.g. to provide a
measure of
future life expectancy and/or the future operational value of the gas meter.
[0094] Turning to FIG. 9, also mounted on driven shaft 220 is a
driven gear 226,
which meshes with an output gear 246 (in the Figures, most of the gear teeth
have been
omitted for clarity). Thus, rotation of driven shaft 220 results in a
proportional rotation of
output shaft 240. While the illustrated embodiment has two gears providing a
1:1 ratio, it
will be appreciated that other gear arrangements and/or other gear ratios may
be used.
[0095] Also notable in the arrangement shown is that the longitudinal
axis 225 of
driven shaft 220 is offset from the longitudinal axis 245 of output shaft 240.
Such an
arrangement may have a number of advantages. For example, in this arrangement
the
location of magnet holder 242 is offset from the position of the end 222 of
driven shaft
220 that, in use, is coupled to a counter drive shaft of a gas meter. As will
be discussed
further below, a backup counter module 200 with offset driven and output
shafts may
facilitate the use of backup counter module 200 with a number of different
sized of gas
meter bodies. Also, offsetting the shafts 220, 240 may reduce the overall size
of backup
counter module 200.
[0096] Turning to FIG. 10, a magnet holder 242 is mounted to output shaft
240 at
the output end 204 of backup counter module 200. Thus, rotation of driven
shaft 220
(e.g. when coupled to and driven by a counter drive shaft of a gas meter body)
results
in: i) incrementation of mechanical counter 230; and ii) rotation of magnet
holder 242.
While any desired gearing may be provided, the gear ratio between driven shaft
220
and mechanical counter 230 is preferably 100:1 (i.e. 100 rotations of driven
shaft 220
results in mechanical counter being incremented by one digit), and the gear
ratio
between driven shaft 220 and magnet holder 242 is preferably 1:1.
[0097] As shown in FIGS. 8-11, worm 224, gears 226, and/or magnet
holder 242
may be mounted to their respective shafts using set screws, flats, and/or keys
and
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keyways. It will be appreciated that any suitable mounting system may be used,
such as
splined shafts.
[0098] Turning to FIG. 11, also provided at the output end 204 are
protrusions
250, 256. These protrusions cooperate with engagement features 120a-c, 126a-c
to
secure backup counter module 200 in one of a number of backup counter module
position 130a-c (see e.g. FIGS. 7A-C). In the illustrated embodiment, backup
counter
module 200 may be secured in housing 110 by positioning protrusions 250, 256
within
recesses 122a, 128a, within 122b, 128b, or within 122c, 128c. As discussed
above this
allows backup counter module 200 to be secured in one of a number of backup
counter
module position 130a-c.
[0099] For example, as shown in FIGS. 13-15, backup counter module
200 may
be secured in a first backup counter module position 130a by positioning
protrusions
250, 256 within recesses 122a, 128a of engagement features 120a, 126a,
respectively.
As perhaps best seen in FIG. 13, by providing a reference against which a
corner of
frame 210 can be aligned, visual aid 129a may assist in positioning backup
counter
module 200 into position for insertion into engagement features 120a, 126a.
[00100] The location of the end 222 of output shaft 220 relative to
the first end 112
of housing 110 when backup counter module 200 is secured in first backup
counter
module position 130a is significant. More specifically, the relative position
of end 222
and flange 111 allows housing 110 with backup counter module 200 secured in
backup
counter module position 130a to be coupled to a gas meter body having a
counter drive
shaft in a complementary position relative to a mounting surface. For example,
as
perhaps best seen in FIG. 2, gas meter body 10A has an aperture 16 for
providing
access to a counter drive shaft in certain relative position to mounting
surface 12.
[00101] Also significant when backup counter module 200 is secured in
backup
counter module position 130a is the location of magnet holder 242 relative to
the inner
surface 116 of housing 110. More specifically, the relative position of magnet
holder 242
and aperture 142 allows magnetic sensor 22 of electronic counter module 20 to
be
positioned in aperture 142 (see e.g. FIG. 2) such that the magnetic sensor 22
is
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operable to track the rotation of output shaft 240 via the rotation of a
magnet held in
magnet holder 242. For example, a Wiegand magnet and corresponding magnet
sensor
may be used, although any suitable tracking system may alternatively be used.
[00102] Thus, with the backup counter module 200 secured in position
130a,
apparatus 100 and backup counter module 200 may be coupled to gas meter body
10A
and used to i) track the relative rotation of the counter drive shaft via
mechanical
counter 230; and ii) allow electronic counter module 20 to track the relative
rotation of
the counter drive shaft via the rotation of a magnet positioned in magnet
holder 242.
[00103] Advantageously, the same apparatus 100 and backup counter
module
200 may alternatively be used with a gas meter body having a different
relative
positioning of its counter drive shaft and mounting surface. For example, this
may be a
gas meter body of a different size, and/or a different model of gas meter.
[00104] For example, as shown in FIGS. 16-21, backup counter module
200 may
be secured in a second backup counter module position 130b by positioning
protrusions
250, 256 within recesses 122b, 128b of engagement features 120b, 126b,
respectively.
As perhaps best seen in FIG. 16, by providing a reference against which a
corner of
frame 210 can be aligned, visual aid 129b may assist in positioning backup
counter
module 200 into position for insertion into engagement features 120b, 126b.
[00105] As with first backup counter module position 130a, the
location of the end
222 of output shaft 220 relative to the first end 112 of housing 110 when
backup counter
module 200 is secured in second backup counter module position 130b is
significant.
More specifically, the relative position of end 222 and flange 111 allows
housing 110
with backup counter module 200 secured in backup counter module position 130b
to be
coupled to a gas meter body having a counter drive shaft in a complementary
position
relative to a mounting surface. For example, as perhaps best seen in FIG. 19,
the
relative position of aperture 16 and mounting surface 12 for gas meter body
10B is
different than their relative position on gas meter body 10A.
[00106] Also, when backup counter module 200 is secured in second
backup
counter module position 130b, the relative position of magnet holder 242 and
aperture
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144 allows magnetic sensor 22 of electronic counter module 20 to be positioned
in
aperture 144b (see e.g. FIG. 19) such that the magnetic sensor 22 is operable
to track
the rotation of output shaft 240 via the rotation of a magnet held in magnet
holder 242.
[00107] Thus, with the backup counter module 200 secured in position
130b,
apparatus 100 and backup counter module 200 may be coupled to gas meter body
10B
and used to i) track the relative rotation of the counter drive shaft via
mechanical
counter 230; and ii) allow electronic counter module 20 to track the relative
rotation of
the counter drive shaft via the rotation of a magnet positioned in magnet
holder 242.
[00108] Similarly, as shown in FIGS. 22-27, backup counter module 200
may be
secured in a third backup counter module position 130c by positioning
protrusions 250,
256 within recesses 122c, 128c of engagement features 120c, 126c,
respectively. As
perhaps best seen in FIG. 22, by providing a reference against which a corner
of frame
210 can be aligned, visual aid 129c may assist in positioning backup counter
module
200 into position for insertion into engagement features 120c, 126c.
[00109] Again, the location of the end 222 of output shaft 220 relative to
the first
end 112 of housing 110 when backup counter module 200 is secured in third
backup
counter module position 130c is significant. More specifically, the relative
position of end
222 and flange 111 allows housing 110 with backup counter module 200 secured
in
backup counter module position 130c to be coupled to a gas meter body having a
counter drive shaft in a complementary position relative to a mounting
surface. For
example, as perhaps best seen in FIG. 25, the relative position of aperture 16
and
mounting surface 12 for gas meter body 10C is different than their relative
position on
either of gas meter bodies 10A or 10B.
[00110] Also, when backup counter module 200 is secured in third
backup counter
module position 130c, the relative position of magnet holder 242 and aperture
144
allows magnetic sensor 22 of electronic counter module 20 to be positioned in
aperture
144a (see e.g. FIG. 25) such that the magnetic sensor 22 is operable to track
the
rotation of output shaft 240 via the rotation of a magnet held in magnet
holder 242.
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[00111] By allowing backup counter module 200 to be alternatively
secured within
housing 110 in more than one backup counter module position, the same
apparatus 100
and backup counter module 200 may alternatively be used with a gas meter body
having a different relative positioning of its counter drive shaft and
mounting surface.
[00112] For example, a manufacturer of gas meter bodies may provide a
common
mounting surface on a number of models and/or sizes of gas meter bodies.
However,
based on the relative location of the impeller within the gas meter body, the
location of
the counter drive shaft relative to the mounting surface may be different for
different
models and/or sizes of gas meter bodies. For example, compare and contrast the
relative locations of mounting surfaces 12 and counter drive shafts 16 in
FIGS. 2, 19,
and 25.
[00113] However, the differing relative positions of counter drive
shafts may
present problems for the installation of a mechanical counter between the gas
meter
body and an electronic counter module. For example, a different mechanical
counter
module and/or a different housing may be required for each different model
and/or size
of gas meter bodies having different relative mounting surface / counter drive
shaft
arrangements.
[00114] The ability to use the same universal apparatus 100 and backup
counter
module 200 with gas meter bodies having different relative positioning of
their
respective counter drive shafts and mounting surfaces may have a number of
advantages.
[00115] For example, the ability to use a universal apparatus 100 and
backup
counter module 200 with multiple gas meter bodies may reduce the number of
different
mechanical counter modules and/or housings that are required to be brought to
a
customer's facility when installing and/or repairing backup counter modules,
as the
same parts may be used with a wide variety of gas meters.
[00116] Also, as noted above, an advantageous result of using a backup
counter
module with a display oriented transverse to a driven shaft is that display is
located the
same distance along the housing 110 regardless of which backup counter module
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CA 3004875 2018-05-14
position it is secured in. As seen in e.g. FIGS. 4, 21, and 27, this allows
display 232 to
be visible through a relatively small viewing window 160 in housing 110
regardless of
which backup counter module position 130a-c the backup counter module 200 is
secured in.
[00117] As used herein, the wording "and/or" is intended to represent an
inclusive
- or. That is, "X and/or Y" is intended to mean X or Y or both, for example.
As a further
example, "X, Y, and/or Z" is intended to mean X or Y or Z or any combination
thereof.
[00118] While the above description describes features of example
embodiments,
it will be appreciated that some features and/or functions of the described
embodiments
are susceptible to modification without departing from the spirit and
principles of
operation of the described embodiments. For example, the various
characteristics which
are described by means of the represented embodiments or examples may be
selectively combined with each other. Accordingly, what has been described
above is
intended to be illustrative of the claimed concept and non-limiting. It will
be understood
by persons skilled in the art that other variants and modifications may be
made without
departing from the scope of the invention as defined in the claims appended
hereto. The
scope of the claims should not be limited by the preferred embodiments and
examples,
but should be given the broadest interpretation consistent with the
description as a
whole.
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