Patent Description:
Flow sensors used in residential gas meters, e.g., a G4 meter, are typically tailored for measurement of gas within a volume range of about <NUM> to <NUM> cubic meters per hour. Such sensors are mass-marketed and are less expensive than sensors used for other ranges of gas flowrates. Sensors for gas meters having a higher gas flowrate capacity (e.g., G6, G10 and G25 meters) may be custom designed. Accordingly, higher-capacity gas meters are expensive.

<CIT> describes a gas flowmeter that includes: a device body which airtightly accommodates a fluid to be measured; an inlet pipe through which the fluid to be measured is made to flow into the device body; and an outlet pipe through which the fluid to be measured is made to flow out from the device body. The gas flowmeter further includes: an ultrasonic flow rate measuring unit which is connected to the outlet pipe and measures a flow rate of the fluid to be measured which flows in the ultrasonic flow rate measuring unit; a connecting pipe which is connected to the outlet pipe; and a flow passage member which is connected to the connecting pipe and has a flow passage shape identical to a shape of the ultrasonic flow rate measuring unit. The gas flowmeter is provided with a support member which fixes the ultrasonic flow rate measuring unit and the flow passage member to each other. With such a configuration, a gas flow meter capable of performing stable flow rate measurement can be implemented.

<CIT> describes a gas flowmeter that includes a device body that airtightly encapsulates a measurement target fluid, an inlet configured to introduce the measurement target fluid into the device body, an outlet configured to exhaust the measurement target fluid from the device body, and a connector that is connected with the outlet. The gas flowmeter further includes a flow rate measuring part of an ultrasonic type that is connected with the connector and calculates a flow rate of the measurement target fluid flowing inside, and a flow path member that is connected with the connector and has a flow path shape identical with that of the flow rate measuring part. The flow rate measuring part and the flow path member are connected with the connector in a vertical direction in such a manner that a side of inflow ports through which the measurement target fluid flows in faces downward.

The same numbers are used throughout the drawings to reference like features and components. Moreover, the figures are intended to illustrate general concepts, and not to indicate required and/or necessary elements.

The disclosure describes structures and techniques for using a gas sensor that is designed to measure a range of gas flowrates that is less than a range of gas flowrates moving through a gas meter. In an example gas meter, a portion of the gas-flow through the meter passes through the gas sensor, and a portion of the gas-flow through the meter passes through at least one bypass module, thereby bypassing the gas sensor module. The total gas-flow through the meter may be determined based in part on measurements made by the gas sensor and based in part on calculations performed on those measurements, wherein the calculations account for gas passing the sensor and going through the bypass module(s).

An example gas meter includes a sensor module and at least one bypass module. An enclosure of the gas meter may define an interior cavity within which a manifold may be configured to include at least one sensor module connector, a plurality of bypass module connectors (which may be the same as the sensor module connector(s)), and an exhaust port. A sensor module may be connected to the sensor module connector of the manifold and may measure a volume of the first gas-flow that flows through the sensor module and into the manifold. A plurality of bypass modules may be connected to the plurality of bypass module connectors of the manifold, respectively, and may be configured to collectively allow a second gas-flow to flow through the plurality of bypass modules, to bypass the sensor module, to flow into the manifold, and to flow out of the exhaust port. A total gas-flow through the meter may be determined based in part on output from the gas sensor module and based in part on calculations performed on that output.

In a first example of the calculations, a percentage of the gas passing through the gas meter that passes through the sensor module is a known constant value at different pressures and/or different flowrates through the gas meter. In this example, the total gas flowing through the meter may be determined based on measurements by the sensor module, multiplied by a value according to this known percentage.

In a second example of the calculations, a percentage of the gas passing through the meter that passes through the sensor module is a known function of the gas flowrate measured by the sensor module. That is, the percentage of gas flowing through the gas sensor module (with the remainder of the gas flowing through the bypass module) is variable and is related to the flowrate measured by the gas sensor module. In this example, the total gas flowrate or volume flowing through the meter may be determined by multiplying the measured gas flowrate by an appropriate, known and/or predetermined value. The value may be a function of the measured gas flowrate value indicated by the sensor module; i.e., the value may be obtained using the measured gas flowrate. Once the measured gas flowrate is obtained, the factor used to determine overall gas flowrate may be obtained from a function, a lookup table, or other means.

<FIG> shows an example gas meter <NUM> having an enclosure <NUM>, defining an interior cavity <NUM>. A manifold <NUM> is located within the interior cavity. A sensor module <NUM> and a representative plurality of bypass modules <NUM>, <NUM>, <NUM> are shown attached to the manifold <NUM>. In the example shown, a first gas flow <NUM> enters the interior cavity <NUM> of the gas meter <NUM> through an input port <NUM>. A second gas flow <NUM> leaves the interior cavity <NUM> passes into the gas sensor <NUM>. Other gas flows <NUM>, <NUM>, <NUM> leave the interior cavity <NUM>, and bypass the gas sensor <NUM>, by passing through bypass modules <NUM>, <NUM>, <NUM>. In an example, the gas flow <NUM> may be approximately equal to (e.g., within <NUM>%) the gas flow <NUM> through one of the bypass modules. The gas flows <NUM>, <NUM>, <NUM> may be approximately equal or may be significantly different. The gas flows <NUM>, <NUM>, <NUM>, <NUM> are unified within the manifold <NUM>, and the outgoing gas flow <NUM> leaves the gas meter <NUM> at exhaust port <NUM>. In a further example, the plurality of bypass modules may include bypass modules having at least two different cross-sectional areas and/or lengths over which gas travels within each bypass module. The plurality of bypass modules may be configured to allow passage of a bypass gas flow that results in a gas flow through the sensor module to be within an operating range of the sensor module.

Accordingly, the manifold <NUM> is configured with sensor module connector(s) and bypass module connector(s). Appropriate sensor module(s) and/or bypass module(s) may be selected and attached to the manifold, according to design requirements, parameters, component availability and component costs. The manifold therefore assists in the design and construction of a gas meter for use with larger customers, which uses a sensor module designed for smaller customers.

The example manifold <NUM> includes one or more each of sensor module connector(s) and bypass module connector(s). In the example shown, sensor module connector <NUM> allows connection of the sensor module <NUM>. While only one sensor module connector and one sensor module are shown, additional sensor module connector(s) may be included on the manifold <NUM>, with appropriate sensor module(s) installed. If the additional sensor module connectors are not needed, they may be plugged.

In the example shown, bypass module connectors <NUM>, <NUM>, <NUM>, <NUM> allow connection of a bypass module or a plug. In the example shown, bypass module connector <NUM> is connected to a plug <NUM>, which prevents gas from leaving the interior cavity <NUM> and entering the manifold <NUM>. Also shown, bypass module connectors <NUM>, <NUM>, <NUM> allow connection of bypass modules <NUM>, <NUM>, <NUM>, respectively. The bypass modules <NUM>-<NUM> allow gas to bypass the sensor <NUM>. In an example, the volume of gas bypassing the sensor is accounted for by use of mathematical relationships between the gas volume measured by the sensor and the characteristics of the bypass modules attached to the manifold.

The sensor module <NUM> shows a representative design; however, different designs may alternatively be used, which locate processor(s), memory device(s) and/or metrology sensor(s) in alternative locations. The sensor module <NUM> shown includes a processing device <NUM>, memory device <NUM> and metrology sensor <NUM>. In other configurations, the processor <NUM> and/or memory <NUM> may be located in a different part of the gas meter <NUM>.

In the example shown, a first gas flow <NUM> enters an interior cavity <NUM> of the gas meter <NUM>. A second flow <NUM> leaves the interior cavity and passes through the sensor module <NUM>. A third flow <NUM> includes gas flows <NUM>, <NUM>, <NUM>, which pass through bypass modules <NUM>, <NUM>, <NUM>. In operation, the gas meter <NUM> determines the gas flow <NUM> by actual measurement of the gas flow <NUM> passing through the sensor <NUM>, and by estimation of the gas flows <NUM> passing through the bypass modules <NUM>, <NUM>, <NUM>. The estimation may be performed by operation of the processing unit <NUM>, using instructions and data stored on the memory device <NUM>.

<FIG> shows an example manifold assembly <NUM> configured for installation within a gas meter (not shown). A sensor module <NUM> is attached to a manifold <NUM> of the manifold assembly <NUM>. The sensor module <NUM> may be configured for use without a bypass module in a smaller meter (e.g., a meter for a residential or small business customer). However, with a bypass module, the sensor module may be used in a mid-sized gas meter. In the example shown, a sensor module <NUM> and a single bypass module <NUM> are attached to the manifold <NUM>. The sensor module <NUM> is configured to measure a first portion of the gas flowing through the meter. The bypass module <NUM> is configured to allow a second portion of the gas flowing through the meter to bypass the sensor module. Accordingly, measurement of the gas flowing through the meter is based on measurement of a quantity of gas measured by the sensor module <NUM>, and a calculation based on characteristics of the bypass module <NUM> installed in the manifold <NUM>. In an example, a look-up table provides a relationship between different measured flowrates of gas (measured by the sensor module <NUM>) and associated percentages of gas that pass through the bypass module <NUM> at those measured flowrates.

Thus, a ratio of a first flowrate of the first gas flow through a sensor module and a second flowrate of a second gas flow through one or more bypass modules may be variable over a range of gas flowrates and/or pressures at an entry port of a gas meter. In such an example, the gas meter may additionally include a processor to compensate for the variability of the ratio by adjusting a calculation of total gas flow, wherein the adjusting of the calculation is based at least in part on a changing gas flowrate measured by the sensor module. In an example, a lookup table may be created with different measured flowrates and the percentage of gas that went though the sensor module and/or the percentage of gas that went through the bypass module(s). This lookup table may be created experimentally for each meter design, or for each meter manufactured.

In a further example, which is outside of the subject-matter of the claims, the bypass module <NUM> may be constructed to bypass a fixed percentage of the gas flowing through the gas meter at all flowrates or gas pressures appropriate for a particular design-requirement. Thus, a ratio of a first rate of the first gas flow through a sensor module and a second rate of the second gas flow through one or more bypass modules may be fixed over a range of gas flowrates and/or gas pressures at an entry port of a gas meter. In such an example, the gas meter may additionally include a processor to calculate the total gas flow, such as by multiplying by an appropriate factor.

<FIG> shows an example manifold assembly <NUM> configured for installation within a gas meter (not shown). The gas meter may be configured to measure larger volumes of gas flow than the gas meter of <FIG>, and may use the same or different sensor module. In the example shown, the sensor module <NUM> may be configured for use without a bypass module in a smaller meter (e.g., a meter for a residential or small business customer). However, with bypass module(s), the sensor module <NUM> may be used in a larger gas meter. In the example shown, a sensor module <NUM> and a plurality of bypass modules <NUM> are attached to the manifold <NUM>. The sensor module <NUM> is configured to measure a first portion of the gas flowing through the meter. Collectively, the bypass modules <NUM> are configured to allow a second portion of the gas flowing through the meter to bypass the sensor module <NUM>. Accordingly, measurement of the gas flowing through the meter is based on measurement of a quantity of gas measured by the sensor module <NUM>, and a calculation based on characteristics of the plurality of bypass modules <NUM> installed in the manifold <NUM>.

In an example, the sensor module <NUM> includes an enclosure <NUM>, which may include a processing unit, memory device, and/or a metrology sensor. Accordingly, the sensor module <NUM> may be configured in the manner of sensor module <NUM> of <FIG>, with processing unit <NUM>, memory device <NUM>, and metrology sensor <NUM>. The metrology sensor <NUM> may be an ultrasonic measuring unit (UMU) or may use other technology as indicated by design requirements.

A plurality of connectors <NUM> may each be configured to allow connection of a bypass module <NUM> or a "plug" or stopper (now shown) to prevent gas flow. Accordingly, the same manifold <NUM> may be used with differing numbers of bypass modules <NUM> to create the desired manifold assembly <NUM>.

In one example, all of the plurality of bypass modules <NUM> may be of the same type, design, size and/or shape, and may be configured to allow the same gas flowrates under like conditions and/or pressures. Accordingly, the same factor could be used to derive the total flowrate from the measured flowrate at all flowrates.

Alternatively, bypass modules having two or more designs, sizes and/or shapes may be selected and used as the plurality of bypass modules. Such diverse bypass modules may be of different type, design, size and/or shape, and may be configured to allow different gas flowrates under like conditions and/or pressures. Advantageously, bypass modules having different characteristics may be selected to allow a desired percentage(s) of the gas flowing through the gas meter to bypass the sensor module over an anticipated range of gas flows through the meter.

Additionally or alternatively, while one sensor module is shown, a bypass module(s) could be replaced by an additional sensor module(s). This would allow a gas meter to measure a greater percentage of the gas flow, and would allow the data from the sensor modules to be compared and contrasted. The data would also allow for the generation of diagnostics, for the performance of self-tests, and for greater flexibility in the design and operation of gas meters configured with two or more sensor modules.

At setup and/or manufacture, at each measured flowrate, a factor is derived (e.g., and added to a lookup table) for use in deriving the total flowrate through the meter. In some example, the factor is adjusted as the gas meter ages.

<FIG> shows an example gas meter <NUM>. In the example shown, a gas flow enters the meter, and within the enclosure of the meter the flow is bifurcated, with separate flows passing through either a sensor module or a bypass module that allows gas to "bypass" the sensor module. The gas flows may be reunified in a manifold before exiting the meter.

The example meter <NUM> includes a measuring, sensor and/or metrology module and a bypass module. The bypass module allows gas to "bypass" the measuring module, thereby allowing utilization of a less expensive sensor module. Gas that bypasses the sensor/metrology module is accounted for by the meter <NUM>. In the example shown, the sensor module and the bypass module are connected to a manifold, which is connected to an outlet of the meter. In the example, the bypass module may have a conic shape and a slot, wherein an opening angle of the bypass module is calculated to create a bypass ratio which depends on, or is a function of, the measured flowrate. In an example, the bypass ratio could than have the response that is similar to <FIG>. The bypass ratio may be the ratio of gas passing through the sensor module divided by the gas passing through the bypass module. In some examples, the bypass ratio is the ratio of gas passing through the sensor module divided by the total gas passing through the meter. In other examples, the numerator and denominator of the ratio could be reversed. Accordingly, the bypass ratio is a ratio, equation and/or relationship that relates two or more of measured, unmeasured and/or total gas, and allows calculation of the overall gas flowrate and/or volume using the measured gas flowrate and/or volume.

The design of the example meter <NUM> allows the minimization or reduction of measurement uncertainty at low flowrates (where pressure drop is not problematic) and reduces or minimizes pressure drop at higher flowrates (where measurement uncertainty is not problematic).

In the example shown, a threaded connector <NUM> allows a gas flow <NUM> to enter an enclosure <NUM> of the meter <NUM>. A first flow <NUM> of gas from within the enclosure <NUM> passes into and through a sensor module or metrology module <NUM>. A second flow <NUM> gas from within the enclosure <NUM> passes into and through a bypass module <NUM>. The first gas flow <NUM> and the second gas flow <NUM> are unified within the manifold <NUM>, and a unified gas flow <NUM> exits the meter <NUM> at threaded connector <NUM>.

In the example according to the present invention, gas meter <NUM> shown, there is only one bypass module <NUM> attached to the manifold <NUM>. In other example gas meters, two or more bypass modules <NUM> could be attached to the manifold. In some examples wherein multiple bypass modules are used, the bypass modules are the same (e.g., same size, shape, length, etc.). In other examples wherein multiple bypass modules are used, the bypass modules may be configured according to two or more designs, each design having one or more differences from one or more other designs. In still other example meters, wherein one or more bypass modules are utilized, the bypass modules may be configured to have a size, shape and/or configuration that is the same, or substantially similar, to the gas-flow passages of the sensor module <NUM>. In example use of one such bypass module, half the gas flow from the meter enclosure into the manifold would pass through the sensor module and half of the gas flow would pass through the bypass module. In example use of two such bypass modules, one-third of the gas flow from the meter enclosure into the manifold would pass through the sensor module and two-thirds of the gas flow would pass through the two bypass modules. In such examples, the percentage of the volume of the total gas flow passing through the meter could be derived by multiplying the measured gas flow by an appropriate factor.

<FIG> shows an example gas meter <NUM>, showing a manifold assembly having a different manifold than was shown in <FIG>. In the example shown, a threaded connector <NUM> allows a gas flow <NUM> to enter an enclosure <NUM> of the meter <NUM>. A first flow <NUM> of gas from within the enclosure <NUM> passes into and through a sensor module or metrology module <NUM>. A second flow <NUM> gas from within the enclosure <NUM> passes into and through a bypass module <NUM>. The first gas flow <NUM> and the second gas flow <NUM> are unified within the manifold <NUM>, and a unified gas flow <NUM> exits the meter <NUM> at threaded connector <NUM>.

<FIG> is an additional perspective view of the manifold assembly <NUM>, rotated approximately <NUM>-degrees and removed from the gas meter <NUM> of <FIG>. The manifold <NUM> is configured for attachment of one bypass module <NUM> and the sensor module <NUM> (substantially obscured in the view of <FIG>) to show the reverse side of the manifold.

<FIG> shows a further example of a manifold assembly <NUM>, a sensor module and bypass module. In the example assembly <NUM>, a sensor module <NUM> and a bypass module <NUM> are connected to a manifold <NUM>.

<FIG> shows an example bypass module <NUM>. A tubular body <NUM> may be made of aluminum or aluminum alloy. An entry fixture <NUM> is configured to smooth the incoming gas flow and reduce turbulence. A footing <NUM> is configured to attach to a manifold (manifold not shown in this view).

<FIG> shows an example bypass module <NUM>. A tubular body <NUM>, entry fixture <NUM> and a footing <NUM> are made of a single material, such as plastic. The entry fixture <NUM> is configured to smooth the incoming gas flow and reduce turbulence. The footing <NUM> is configured to attach to a manifold (not shown).

<FIG> shows an additional example of a manifold assembly <NUM>. In the example, a sensor module and a plurality of bypass modules result in less measured gas flow and more bypassed gas flow. The sensor module <NUM> is associated with an enclosure <NUM>, which may include a processing unit, memory device, and/or a metrology sensor. A plurality of bypass modules <NUM> allow gas to enter the manifold <NUM> without passing through the sensor module <NUM>. The manifold <NUM> has an exhaust port <NUM> which exhausts gas that has passed through any of the sensor module <NUM> or bypass modules <NUM>.

<FIG> is shown with a manifold <NUM> having a single sensor module <NUM> and six bypass modules <NUM>. In an alternative, one or more of the bypass modules <NUM> could be replaced by an additional sensor module <NUM>. This would result in a greater percentage of the overall gas flow going through a sensor module and a small percentage of the overall gas flow going through a bypass module. Additionally, this would provide two sources of gas flowrate data. These data flows could be compared over time, and diagnostics could be generated. In an example, degraded performance of one of the sensor modules may be assumed, if the percentage of the overall gas flow measured by the two sensor modules changes. Accordingly, while <FIG> shows one sensor module and six bypass modules, any number of sensor modules and bypass modules could be used. In a further example, where two or more sensor modules are used, one or more of the sensor modules may be turned off during period(s) of time, such as in response to higher or lower gas flows.

<FIG> shows an example gas meter <NUM>. An entry port <NUM> receives gas, such as from a utility company. An exit port <NUM> exhausts gas after measurement, such as to a utility customer. The enclosure <NUM> is shown as partially transparent to provide a view of the interior of the meter. Within the meter, the manifold assembly <NUM> of <FIG> is shown. The manifold assembly <NUM>, with a sensor module and a plurality of bypass modules measures gas before it exits the meter at port <NUM>.

A deflector or baffle <NUM> regulates the flow of gas from the entry port <NUM> tends to reduce turbulence and create a more laminar flow of gas as it moves toward the manifold assembly <NUM>.

<FIG> shows an example gas meter <NUM>. Gas <NUM> (e.g., from a utility company) enters the gas meter at entry port <NUM>. The gas flow <NUM> is directed in part by a baffle <NUM>, which reduces turbulence. The gas flow <NUM> travels between baffles <NUM>, <NUM>. The gas flow <NUM> proceeds toward the opposite end of the gas meter, where gas flow <NUM> is redirected by the inside surface of the enclosure <NUM>. Gas flow <NUM> approaches the sensor module <NUM>, having an enclosure <NUM> for a processor, memory, and a sensor device. Gas also enters a bypass module <NUM>. Within the module <NUM>, the gas flows from the sensor module <NUM> and bypass module <NUM> are unified as gas flow <NUM>. Gas flow <NUM> then exits through exhaust port <NUM>.

The gas meter <NUM> shows that one or more baffles <NUM>, <NUM> can reduce turbulence and increase laminar gas flow characteristics. Also, by putting the input of the sensor module <NUM> and the bypass module <NUM> near a wall of the enclosure <NUM>, gas turbulence is also reduced. By reducing turbulence, a more accurate gas flowrate measurement is made.

<FIG> shows a top view of an example manifold assembly <NUM>. The assembly includes a gas sensor module <NUM>, bypass module <NUM>, and manifold <NUM>. The sensor module <NUM> and bypass module <NUM> are attached to the manifold <NUM>.

<FIG> shows a side-view of the example manifold assembly <NUM>. An input port <NUM>, an exhaust port <NUM>, and the manifold <NUM> are shown. The valve assembly <NUM> allows the exhaust port <NUM> to be closed.

<FIG> is a top view of an example manifold assembly <NUM>. A gas entry connector or port <NUM> and the shut-off valve <NUM> are shown. The sensor module <NUM> and bypass module <NUM> are also shown.

<FIG> is an end view of the manifold assembly <NUM>. The exhaust port <NUM> and valve assembly <NUM> are shown.

<FIG> is an end view of the manifold assembly <NUM>, bypass module, and sensor module. The gas inlet port <NUM> is shown. The sensor module <NUM> and bypass module <NUM> are attached to the manifold. Module <NUM> encloses electronics, which may include one or more of a processing unit, memory device, and/or metrology sensor.

<FIG> is a perspective view of the manifold <NUM>, bypass module, sensor module and valve <NUM>. The entry port <NUM> and exhaust port <NUM> are shown. The sensor module <NUM> and bypass module <NUM> are.

<FIG> shows a compound manifold assembly <NUM>. In the example, three pairs of sensor modules and bypass modules are shown. Sensor modules <NUM>, <NUM> are seen in the foreground, and are associated with respective bypass modules <NUM>, <NUM>. Each sensor module has an electronics module <NUM>, which may include one or more of a processor unit, a memory device, and/or a metrology sensor. Each sensor module and bypass module pair exhausts gas into a secondary manifold <NUM>. Each secondary manifold exhausts gas into a collector pipe <NUM>, which transfers gas to a primary manifold <NUM>. Gas is finally exhausted from an outlet <NUM>. The compound manifold assembly <NUM> may be contained within an enclosure (not shown for clarity) of a gas meter.

In an example, any of the gas manifold assemblies of the previous figures (e.g., manifold assembly <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, etc.) could be attached to the primary manifold <NUM>. Accordingly, a gas meter having a larger gas flowrate-measuring capacity could be configured with a primary manifold <NUM> attached to (fed by) any combination (e.g., mix or match) of sensor module(s)/bypass module(s) of the earlier figures.

In some examples of the compound manifold assembly <NUM>, the assembly is configured so that a distance from an opening of each sensor module <NUM> and each bypass module <NUM> is the same distance. Such a configuration may result in increased accuracy of gas flowrate measurement.

In some examples, a position of the on/off valve of one or more of the manifold assemblies used to form the compound manifold assembly may be changed. Such valve settings may further customize the compound manifold assembly.

<FIG> shows an example chart <NUM> illustrating a bypass ratio for different total gas flowrates. In some meters, a fixed percentage of gas flows through the sensor module. In an example, if <NUM>% of the gas flow is though the sensor module, then total gas flow is twice measured gas flow. This calculation is easily made if a different fixed percentage of the gas flows through the sensor module.

In other meters, the percentage of gas flowing through the sensor module is fixed over time for any given gas flowrate. However, for different gas flowrates, the percentage of gas flowing through the sensor module varies. <FIG> addresses this issue. By experimentation, the graph and/or associated lookup table can be created. The experimentation may be made for any particular meter design or for any particular meter (i.e., a custom lookup table for each meter manufactured).

In operation, a gas meter may determine a sequence of flowrates, as a customer uses gas. Using a lookup table, a gas meter may determine an appropriate factor for each measured flowrate, to determine a total gas flowrate. Thus, gas measurement includes measuring a flowrate and obtaining a factor associated with the flowrate to yield total gas flowrate.

In the example <NUM>, the percentage of the gas passing through bypass module(s) is equal to the percentage of gas measured at <NUM>. The percentage of gas passing through bypass module(s) is slightly higher at <NUM> and lower at <NUM> than the percentage of gas passing through the sensor module.

<FIG> shows example methods <NUM> and operation of a gas meter. The methods and operation may be performed and/or directed by any desired processor, memory, integrated circuit, logic devices, programming, etc. A controller may include one or more of the processor, memory and/or other devices. The example methods of <FIG> may be implemented at least in part using the structures and techniques illustrated by <FIG>. However, the methods of <FIG> contain general applicability, and are not limited by other drawing figures and/or prior discussion. The functional blocks of <FIG> may be implemented by software and/or hardware structures or devices that are configured to operate a gas meter.

In some examples of the techniques discusses herein, the methods of operation may be performed by one or more application specific integrated circuits (ASIC) or may be performed by a general-purpose processor utilizing software defined in computer readable media. In the examples and techniques discussed herein, the memory <NUM> may comprise computer-readable media and may take the form of volatile memory, such as random-access memory (RAM) and/or non-volatile memory, such as read only memory (ROM) or flash RAM. Computer-readable media devices include volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules, or other data for execution by one or more processors of a computing device. Examples of computer-readable media include, but are not limited to, phase change memory (PRAM), static random-access memory (SRAM), dynamic random-access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to store information for access by a computing device.

As defined herein, computer-readable media does not include transitory media, such as modulated data signals and carrier waves, and/or signals.

<FIG> shows an example method <NUM> by which a volume of gas is measured in a gas meter having a manifold with attached sensor module(s) and bypass module(s). In the example, a gas flow is received by the gas meter. A portion of the gas flow is passes through a gas sensor module, where it is measured. Another portion of the gas flow passes through one or more bypass modules, thereby bypassing the gas sensor module. A manifold provides connectors to allow attachment of the gas sensor module(s) and/or the bypass module(s). A relationship between two or more of: a volume of gas flowing into the meter; a volume of gas flowing through the gas sensor module(s); and a volume of gas flowing through the bypass module(s) is known over a range of gas flowrates. Accordingly, by using the relationship and measured values from the gas sensor module, a flowrate of gas flowing through the meter, and a volume of gas that passed through the meter over time, can be determined.

At block <NUM>, a first gas flow having a first gas flowrate is received into an interior of a gas meter.

At block <NUM>, a second gas flow, having a measured second gas flowrate, is measured by operation of a sensor module. The measured second gas flowrate is a portion of the first (i.e., total) gas flow rate. In the example of block <NUM>, the measuring may be performed by one or more sensor modules. The sensor modules may be connected to a manifold within a gas meter.

At block <NUM>, a third gas flow bypasses the sensor module(s) and is carried by a bypass module. In the example of block <NUM>, the third gas flow bypasses the sensor module(s) by passing through a plurality of bypass modules.

In the example of block <NUM>, gas flow is blocked from flowing into the manifold by one or more stoppers or plugs. Accordingly, the gas is routed into the manifold through the sensor module(s) or the bypass module(s).

At block <NUM>, data (such as a multiplicative factor) is obtained to compensate for variability of a ratio of the measured second gas flowrate to the third gas flow rate. That variability is seen in <FIG>. In an example, the variability (and compensation for the variability) may be based at least in part on the measured second gas flowrate. In an example, the variability may be based at least in part on a number of bypass modules used. In the example of block <NUM>, the gas flowrate through the meter is measured (e.g., a flowrate measured at the sensor module) and data (e.g., a multiplicative factor) based on the measured flowrate (e.g., data from <FIG> that indicates a factor to be used to at different gas flowrates to obtain the overall gas flowrate) is used to obtain the overall flowrate (i.e., measured plus bypassed flowrates). In an example of <FIG>, the data or multiplicative factor is approximately <NUM> for most measured gas flows. That is, approximately half of the overall gas flow is measured, and the full gas flow is (approximately) the measured gas flow times two. However, for some gas flowrates, it is less than <NUM>, and for some gas flowrates it is more than <NUM>. Accordingly, there is variability in the multiplicative factor, which may be repeatedly updated from a lookup table, as the sensor module makes measurements. If an additional bypass module was used, the factor might increase. In the example of block <NUM>, a plurality of values may be used for the ratio of the measured second gas flowrate to the third gas flow-rate for each of a respective plurality of measured second gas flowrates. In the example of block <NUM>, a lookup table is accessed, which may be customized for the gas meter design, or for the gas meter individually.

Because ratio of any two of the measured gas flowrate, the bypassed gas flowrate, and the total gas flowrate, and the inverse of the ratios, all convey the same or similar information, any one of the ratios can be used as a factor to determine a total flowrate from a measured flowrate. Accordingly, statement of one relationship implies and includes the others.

At block <NUM>, the first gas flowrate is determined. The determination may be made based on input including the measured second gas flowrate and a compensation factor for the variability of a measured gas flowrate and a bypassed gas flowrate.

At block <NUM>, in an example, output from two sensor modules may be compared to determine if the output is within a threshold difference and/or whether the gas meter should be replaced. If the output of the two sensor modules have a ratio or other relationship that has changed, then that change may indicate a failure of the gas meter.

Claim 1:
A gas meter (<NUM>), comprising:
an enclosure (<NUM>) defining an inlet port (<NUM>), an outlet port (<NUM>), and an interior cavity (<NUM>);
a manifold (<NUM>) located within the interior cavity of the enclosure, comprising a first connector, a second connector, and a third connector, wherein the manifold is connected to the outlet port to exhaust gas through the outlet port;
a valve connected to the manifold to regulate gas flow from the manifold to the outlet port;
a sensor module (<NUM>), connected to the first connector of the manifold, and configured to measure a first gas flowrate from the interior cavity of the enclosure, through the sensor module, through the manifold and out the outlet port;
a bypass module (<NUM>, <NUM>, <NUM>) connected to the second connector of the manifold, to direct a second gas flow having a second gas flowrate from the interior cavity of the enclosure, through the bypass module, through the manifold, and out the outlet port; and
a plug (<NUM>) connected to the third connector (<NUM>), to block gas flow from entering the manifold through the third connector; and
a processor (<NUM>) to compute a total gas flowrate through the gas meter using inputs comprising:
a measured gas flowrate through the sensor module; and
an adjustment factor, the adjustment factor being based on the measured gas flowrate; wherein the adjustment factor is obtained by:
using a plurality of values for the factor for each of a respective plurality of measured second gas flowrates.