Magnetic sensing metering device and method

Methods and systems for implementing a rotation sensing device are provided. The rotation sensing device may include a magnet, a magnetic field sensor located in a fixed position relative to the magnet, the magnetic field sensor configured to sense a magnetic field of the magnet, and a flux conductor configured to alter the magnetic field of the magnet, wherein the flux conductor is mounted to a rotatable element. The magnet may be mounted in a fixed position relative to the flux conductor, and the magnetic field sensor may be configured to generate a signal based on a sensed strength of the magnetic field in accordance with rotation of the flux conductor.

FIELD

The present disclosure relates to rotation sensing devices, such as to rotation sensing devices used to measure a quantity, degree, or rate of something and/or some material.

BACKGROUND

Utility companies use meters to measure various commodities. These commodities can include resources like electricity, gas, and water. Meters can include a dial device that can indicate the amount of the commodity consumed. For example, the dial can indicate a volume of gas that has been consumed over time by a household. The dial may move responsive to the gas moving through a metering valve.

SUMMARY

The present disclosure provides a description of rotation sensing devices and sensing rotation, such as through the use of magnetic fields and magnetic flux paths. Rotation sensing devices may include a rotatable element that may indicate consumption of a material. For example, a meter (e.g., utility meter, etc.) may include a dial or index that may rotate based on a consumed resource, such as gas, electricity, or water. In some cases, the meter may be configured so that the number of rotations (or partial rotations) of the rotatable element may indicate (e.g., be proportional to) the volume of the material passing through a metering valve. In some situations, the rotatable element may indicate the amount of consumption of the resource according to number the rotations of the rotating device. In some cases, the meter may indicate, record, and/or measure time or an amount of something (e.g., a parking meter).

Aspects described herein provide for a rotation sensing device that may include a magnet, a magnetic field sensor located in a fixed position relative to the magnet, the magnetic field sensor configured to sense a magnetic field of the magnet, and a flux conductor configured to alter the magnetic field of the magnet, wherein the flux conductor is mounted to a rotatable element. The magnet may be mounted in a fixed position relative to the flux conductor, and the magnetic field sensor may be configured to generate a signal based on a sensed strength of the magnetic field in accordance with rotation of the flux conductor.

Aspects described herein provide for a method of sensing rotation that may include generating a magnetic field by a magnet disposed at a fixed location, altering the generated magnetic field via flux conductor mounted to an element that rotates relative to the magnet, sensing, by a magnetic field sensor, a magnetic field strength of the generated magnetic field, wherein the magnetic field sensor is located in a fixed position relative to the magnet, and generating, by the magnetic field sensor, a signal based the sensed magnetic field strength.

DETAILED DESCRIPTION

FIG. 1Aillustrates a top view of an exemplary embodiment of a rotation sensing device100in a first configuration. In some embodiments, the rotation sensing device100may be part of or may be a meter (e.g., utility meter, time meter, parking meter, etc.) The rotation sensing device100may include a magnet102, a magnetic field sensor104, and a housing or cover106. According to some aspects, the magnet102and/or the magnetic field sensor104may be attached to or mounted to the cover106, such as via the attachment structures114and/or116. In some embodiments, the magnet102and/or the magnetic field sensor104may be attached or mounted directly to the cover106or to another component of the rotation sensing device100, such as a printed circuit board118. The rotation sensing device100may include a flux conductor108, which may be mounted to or attached to a rotatable element110. The rotatable element110may be attached to a dial112(e.g., an index, a register, etc.), which may indicate a quantity or measure of a material or something else (e.g., time, etc.). In some embodiments, the flux conductor108may be the rotatable element110. According to some aspects, one or more ends or legs of the flux conductor108can extend over the rotatable element110. In some embodiments, the rotatable element110may be a dial hand of the dial112and may rotate based on a measured quantity, which may indicate consumption of a material. The flux conductor108and/or the rotatable element110may rotate about an axis of rotation101, such as in a clockwise or counter-clockwise manner about the axis of rotation101. The rotation sensing device100may include a printed circuit board118and a processing device120(e.g., a computer processor having a memory device), which may be attached to the cover106. The magnet102and/or the magnetic field sensor104may be coupled to the printed circuit board118and/or to the processing device120. In some embodiments, the processing device120may communicate with the magnetic field sensor104wirelessly and/or via a wire or other connecting device (e.g., via the circuit board118, etc.).

The magnet102may be an electromagnet or a permanent magnet such as neodymium. The magnet102may be configured in any manner. For example, as shown inFIG. 1A, the north pole of the magnet102may face the cover106, and the south pole of the magnet102may face the dial112. The magnetic field sensor104may be a reed switch, a Hall effect sensor, a magneto resistive element, and the like. The magnetic field sensor104may be located in a fixed position relative to the magnet102. For example, the magnet102and the magnetic field sensor104may be fixedly mounted to the cover106. In another example, the magnet102may be mounted to the cover106and the magnetic field sensor104may be mounted to the circuit board118. In another example, the magnet102and or magnetic field sensor104may be mounted to the dial112or to another component of the rotation sensing device100.

The magnetic field sensor104may be configured to detect the presence of the magnet102. For example, the magnetic field sensor104may sense a magnetic field generated by the magnet102. According to some aspects, the magnet102may be located at a distance from the magnetic field sensor104, such that the distance is sufficiently far enough to prevent the magnetic field sensor104from detecting the presence of the magnet102, such as by not sensing the magnetic field generated by the magnet102. For example, the distance between the magnet102and the magnetic field sensor104may be a function of the magnetic field strength of the magnet102or may be a function of the sensitivity of the magnetic field sensor104, such that the magnetic field strength might not be normally not sensed by the magnetic field sensor104. In some scenarios, the magnet102and the magnetic field sensor104may be spaced apart based on the strength of the magnet102and on the sensitivity of the magnetic field sensor104such that the strength of magnetic field sensed by the magnetic field sensor104is below a threshold value that might not activate the magnetic field sensor104.

According to some aspects, the magnetic field sensor104may sense the magnetic field strength of the magnetic field in accordance with or based on the rotation of the flux conductor108. The flux conductor108may be composed of a material with high relative permeability (e.g., low magnetic resistance), such as iron, nickel, or cobalt. For example, the flux conductor108may be a magnetically conductive strip of metal, which might not be magnetized. Table 1 below shows a list of materials and respective relative permeability for each of these materials.

Accordingly, a suitable material for the flux conductor108may be one with a high relative permeability and/or low magnetic resistance. In the context of this application, “high relative permeability” means a relative permeability of about 5 or higher.

The flux conductor108may have any shape. For example, the flux conductor108may have a substantially elongated shape. The flux conductor108may have length and a width, such that the length may be longer than a width. The flux conductor108may have one or more substantially broad surfaces, such that one of the broad surfaces may be adjacent to and/or attached to the rotatable element110. In some embodiments, the flux conductor108may comprise two broad surfaces, one on each of the opposing sides of the flux conductor108.

In some embodiments, as the rotating rotatable element110rotates, the flux conductor108may alternatively enhance a magnetic flux path between the magnet102and the magnetic field sensor104, which may cause the magnetic field sensor104to activate, such as if the flux path is enhanced, or may cause the magnetic field sensor104to deactivate (or otherwise be non-activated), such as if the enhancement to the flux path is removed. For example, because the flux conductor108exhibits a high relative permeability, such as compared to the surrounding fluid or gas (e.g., water, air, vacuum, etc.), the flux conductor108may enable the generated magnetic field or magnetic flux to follow a flux path along the length or longitudinal direction of the flux conductor108, such as shown inFIGS. 1A-1C. In an example where the magnetic field sensor104comprises a switch, such as a reed switch, the activated state of the magnetic field sensor104may correspond to a closed state of the switch, and the deactivated state of the magnetic field sensor104may correspond to an opened state of the switch. In an example where the magnetic field sensor104comprises a Hall effect sensor or a magneto resistive element, the magnetic field sensor104may generate a signal, such as a voltage signal or an electrical resistance signal, which may be based on or a function of (e.g., proportional to, etc.) the strength of a sensed magnetic field. In some of these embodiments, one or more thresholds may be used (e.g., by the processing device120) to distinguish between an activated state and a deactivated state.

FIG. 1Billustrates a front view of the rotation sensing device100.FIG. 1Bmay be a front view of the top view shown inFIG. 1A. The magnet102and the magnetic field sensor104may be located a distance apart, such that the magnet102's magnetic field (shown via the flux path) might not normally be sensed or detected by the magnetic field sensor104, such as illustrated inFIG. 1D, which shows a front view of the rotation sensing device100configured without the flux conductor108. Referring back toFIG. 1B, as the rotatable element110rotates (e.g., based on consumption of a material, like natural gas), the flux conductor108(which may be mounted or fixed to the rotatable element110) may also rotate, such as about the axis101. As the flux conductor108rotates to a position, such as shown inFIGS. 1A and 1B, such that the flux conductor108may be substantially longitudinally aligned between the magnet102and the magnetic field sensor104, the flux conductor108may cause the magnetic field strength to be sensed by the magnetic field sensor104. For example, the flux conductor108may direct the magnetic flux towards the magnetic field sensor104to effectively enhance or extend the magnetic field along the length or longitudinal direction of the flux conductor108, which may enable the magnetic field (i.e., the magnetic field strength) to be detected or sensed by the magnetic field sensor104. For example, because the magnet102's magnetic field might not normally be sensed or detected by the magnetic field sensor104, the extension of the magnetic flux path along the length of the flux conductor108may enable the magnetic field sensor104to detect the magnetic field. According to some aspects, the magnetic field sensor104may activate responsive to detecting or sensing the magnetic field. For example, the magnetic field sensor104may normally be in an deactivated state because the magnetic field sensor104might normally not sense the magnetic field generated by the magnet102. In the deactivated state, the magnetic field sensor104may produce a signal indicating the deactivated state, such as a low signal (e.g., a digital “0”), such as via the circuit board118and/or processing device120.

An illustration of the exemplary signals generated by the magnetic field sensor104may be shown inFIG. 2A. As shown inFIG. 2A, the signal may begin at a low state at time t0, such as when the magnetic field sensor104might not detect the magnetic field and may be in a deactivated state. As the flux conductor108rotates to a position as shown inFIG. 1B, the magnetic field sensor104may detect the magnetic field due to the enhancement or extension of the flux path between the magnet102and the magnetic field sensor104, and the magnetic field sensor104may activate at time t1. In the activated state, the magnetic field sensor104may generate a high signal (e.g., a digital “1”), such as via the circuit board118and/or processing device120. As shown inFIG. 2A, the signal may be at a high state if the magnetic field sensor104detects the magnetic field (or detects a threshold value of the magnetic field strength), such as if the flux conductor108is configured as shown inFIG. 1B. In embodiments where the magnetic field sensor104comprises a Hall effect sensor or a magneto resistive element, the magnetic field sensor104may generate a voltage signal based on the strength of a sensed magnetic field. In these embodiments, the signal generated by the magnetic field sensor104may also oscillate between a high value and a low value. In some of these embodiments, one or more thresholds may be used (e.g., by the processing device120) to distinguish between an activated state that may result in a high signal (e.g., a digital “1”) and a deactivated state that may result in a low signal (e.g., a digital “0”).

FIG. 1Cillustrates a front view of the rotation sensing device100. As illustrated, the magnet102and the magnetic field sensor104may be located a distance apart, such that the magnet102's magnetic field might not normally be sensed or detected by the magnetic field sensor104. As the rotatable element110rotates (e.g., based on consumption of a material, like natural gas), the flux conductor108(which may be mounted or fixed to the rotatable element110) may also rotate, such as about the axis101shown inFIG. 1A. The flux conductor108may rotate to a position, such as shown inFIG. 1C, such that the flux conductor108might not be substantially longitudinally aligned between the magnet102and the magnetic field sensor104. For example, the length of the flux conductor108may be oriented substantially transverse to a path between the magnet102and the magnetic field sensor104(e.g., transverse to a substantially straight path between the magnet102and the magnetic field sensor104).

In some embodiments, if the length of the flux conductor108is not substantially aligned between the magnet102and the magnetic field sensor104, the flux conductor108may cause the strength of the magnetic field in the vicinity of the sensor104to be diminished. For example, the flux conductor108may divert the magnetic field along the length of the flux conductor, which may effectively divert the magnetic field away from the magnetic field sensor104. In such situations, because the flux conductor108might not be enhancing the flux path between the magnet102and the magnetic field sensor104, the magnetic field strength might not be sensed by the magnetic field sensor104, such as in the default situation where the magnetic field might not be normally sensed by the magnetic field sensor104(e.g., as shown inFIG. 1D), and the magnetic field sensor104may deactivate. In the deactivated state, the magnetic field sensor104may generate a low signal (e.g., a digital “0”), such as at time t2, as shown inFIG. 2A. In some embodiments, the flux conductor108may provide a low resistance flux path for the generated magnetic field along the length of the flux conductor108, such that the flux path from one pole of the magnet102(e.g., north) enters one end of the flux conductor108and out the other end of the flux conductor108to the other pole of the magnet102. In these embodiments, and where the length of the flux conductor108may be oriented substantially transverse to a path between the magnet102and the magnetic field sensor104, the magnetic field might not be sensed by the magnetic field sensor104, and the magnetic field sensor may generate a low signal (e.g., a digital “0”).

According to some aspects, as the flux conductor108rotates 180 degrees from the position shown inFIG. 1B, the flux conductor108may again enhance the flux path between the magnet102and the magnetic field sensor104, such that the magnetic field sensor104may detect the magnetic field, activate, and generate a high signal indicating an activated state at time t3, such as shown inFIG. 2A. The magnetic field sensor104may continue (e.g., at times t4, t5, etc.) to generate such a signal shown inFIG. 2Abased on the rotation of the flux conductor108.

According to some aspects, in the context of a meter, the rotation sensing device100may be used to sense or count rotations of the rotatable element110(e.g., a rotating index hand), which can measure or indicate the amount of consumption of a quantity or material (e.g., gas, electricity, water, time, etc.). For example, the processing device120may count rotations based on the signals produced by the magnetic field sensor104. In one example, the processing device120may count a full rotation if the magnetic field sensor104generates a low signal, a high signal, a low signal, and a high signal, which may indicate a 360 degree rotation of the rotatable hand110and/or flux conductor108. Alternatively or additionally, the processing device102may count a full rotation if the magnetic field sensor104generates a high signal, a low signal, a high signal, and a low signal. Other permutations and combinations may be used by the processing device120to count a rotation. According to some aspects, the processing device102may count partial rotations based on the signal generated by the magnetic field sensor104. For example, the processing device102may count a ½-rotation (half rotation) if the magnetic field sensor104generates a low signal and a high signal, or alternatively, a high signal and a low signal.

FIG. 3Aillustrates a top view of an exemplary embodiment of the rotation sensing device100in a second configuration, which may include one or more components as described with respect toFIG. 1A-1C. For example, the rotation sensing device100may include a magnet102, a magnetic field sensor104, a cover106, and a flux conductor108, which may be attached to a rotatable element110, which may be attached to a dial112. In some embodiments, the flux conductor108may be the rotatable element110. The magnet102may be configured in any manner. For example, as shown inFIG. 3A, the north pole of the magnet102may face the cover106, and the south pole of the magnet102may face the dial112. The magnetic field sensor104may be located in a fixed position relative to the magnet102. The flux conductor108and the rotatable element110may rotate about an axis of rotation101, such as in a clockwise or counter-clockwise manner about the axis101. The rotation sensing device100may include a printed circuit board118and a processing device120. The magnet102and/or the magnetic field sensor104may be attached or mounted to the cover106, and in some embodiments mounted via respective attachment structures114or116. In some embodiments, the magnetic field sensor104may be coupled to the circuit board118and/or processing device120via an attachment structure, such as a wire, or may be wirelessly coupled.

According to some aspects, the magnet102may be located at a distance from the magnetic field sensor104, such that the distance is sufficiently close enough to enable the magnetic field sensor104to the presence of the magnet102, such as by detecting the presence of a magnetic field (i.e., magnetic field strength) generated by the magnet102. For example, the distance between the magnet102and the magnetic field sensor102may be a function of the magnetic field strength of the magnet102or on the sensitivity of the magnetic field sensor104, such that the magnetic field strength may be normally sensed by the magnet field magnetic field sensor104, such as shown inFIG. 3D, which shows a front view of the rotation sensing device100configured without the flux conductor108. In some scenarios, the magnet102and the magnetic field sensor104may be spaced apart based on the strength of the magnet102and on the sensitivity of the magnetic field sensor104such that the strength of magnetic field sensed by the magnetic field sensor104may be greater than a threshold value that may activate the magnetic field sensor104.

According to some aspects, the magnetic field sensor104may sense the strength of the magnetic field in accordance with or based on the rotation of the flux conductor108. As the rotatable element110rotates (e.g., based on consumption of a material, like natural gas), the flux conductor108(which may be mounted or fixed to the rotatable element110) may also rotate, such as about the axis101. The rotation of the flux conductor108may be configured to divert a magnetic flux path between the magnet102and the magnetic field sensor104via the flux conductor, which might cause the magnetic field to be not sensed by the magnetic field sensor104. For example, as shown inFIG. 3A, the flux conductor108may be “U-shaped” or shaped like an arch, and one of the legs of the arch may be attached to the rotatable element110. In some other embodiments, the flux conductor108may have a substantially elongated shape. The flux conductor108may extend in a vertical direction, such that the length of the flux conductor108may extend vertically from the rotatable element110and/or dial112towards the cover106. As the flux conductor108rotates to a position, such as shown inFIG. 3A and 3B, the magnetic field generated by the magnet104may follow a flux path into and out of the arch shape of the flux conductor108, in a manner to provide a low magnetic resistance flux path between the poles of the magnet104. For example, the flux conductor108may rotate to the position shown inFIGS. 3A and 3B, so that the “open” end of the arch (i.e., the two legs of the flux conductor108) may face the magnet102and/or be proximate to the magnet102. According to some aspects, the magnetic flux path from one pole of the magnet (e.g., north pole) may enter into one leg of the arch may follow the arch, where the magnetic flux path may exit the other leg of the arch and into the opposite magnetic pole of the magnet104(e.g., south pole).

According to some aspects, the magnetic field sensor104may deactivate responsive to no longer detecting or sensing the magnetic field generated by the magnet102. For example, the magnetic field sensor104may normally be in an activated state because the sensor may normally sense the magnetic field generated by the magnet102, such as shown inFIG. 3D, which shows a front view of the rotation sensing device100configured without the flux conductor108. In the activated state, the sensor may produce a signal indicating the activated state, such as a high signal (e.g., a digital “1”), such as via the circuit board118and/or processing device120. An illustration of the exemplary signals generated by the magnetic field sensor104may be shown inFIG. 2B. As shown inFIG. 2B, the signal may begin at a high state at time t0, such as when the magnetic field sensor104may detect the magnetic field and may be in an activated state.

As the flux conductor108rotates to a position as shown inFIG. 3B, the magnetic field sensor104might not detect the magnetic field due to the flux conductor108diverting the flux path between the magnet102and the magnetic field sensor104, and the magnetic field sensor104may deactivate. In the deactivated state, the magnetic field sensor104may generate a low signal (e.g., a digital “0”) at time t1, such as via the circuit board118and/or processing device120. As shown inFIG. 2B, the signal may be at a low state if the magnetic field sensor104does not detect the magnetic field (or does not detect a threshold value of the magnetic field strength). According to some aspects, the magnetic field sensor104may activate responsive to detecting or sensing the magnetic field, and may generate a high signal indicating an activated state at time t2, such as if the flux conductor108rotates to another position, such as shown inFIG. 3C.

FIG. 3Cillustrates a front view of the rotation sensing device100. As the rotatable element110rotates (e.g., based on consumption of a material, like natural gas), the flux conductor108(which may be mounted or fixed to the rotatable element110) may also rotate, such as about the axis101. The flux conductor108may rotate to a position, such as shown inFIG. 3C, such that the flux conductor108might not be located between the magnet102and the magnetic field sensor104, such that the flux conductor108might not provide a low magnetic resistance flux path to divert (or otherwise diminish) the magnetic field generated by the magnet102. For example, the magnet102and the magnetic field sensor104may be located a distance apart, such that the magnet102's magnetic field may be sensed or detected by the magnetic field sensor104, such as shown inFIG. 3D(e.g., in a default situation and/or if the flux conductor108is not diverting the flux path). In some embodiments, the flux conductor108may rotate to the position shown inFIG. 3C, so that the “open” end of the arch (i.e., the two legs of the flux conductor108) may face away from the magnet102(i.e., not face toward the magnet102). According to some aspects, the magnetic field sensor104may activate at time t2responsive to detecting or sensing the magnetic field, and may generate a high signal indicating an activated state, such as shown inFIG. 2B.

According to some aspects, as the flux conductor108rotates, the flux conductor108may again divert the flux path between the magnet102and the magnetic field sensor104(e.g., such as if the flux conductor108reaches the position shown inFIG. 3B), such that the magnetic field sensor104might not detect the magnetic field, deactivate (or otherwise be non-activated), and generate a low signal at t3indicating a deactivated state, as shown inFIG. 2B. The magnetic field sensor104may continue to generate such a signal shown inFIG. 2Bbased on the rotation of the flux conductor108. For example, the magnetic field sensor104may activate at time t4responsive to detecting or sensing the magnetic field.

According to some aspects, and as described above with respect toFIGS. 3A-3Cin the context of a meter, the rotation sensing device100may be used to sense or count rotations of the rotatable element100(e.g., a rotating index hand), which can measure or indicate the amount of consumption of a quantity of material (e.g., gas, electricity, water, time, etc.). For example, the processing device120may count a full rotation based on the signals produced by the magnetic field sensor104. In one example, with respect toFIGS. 3A-3C, the processing device120may count a full rotation if the magnetic field sensor104generates a low signal and a high signal. Other permutations and combinations may be used by the processing device120to count a rotation or a partial rotation.

FIG. 4is an exemplary process400for sensing rotation, such as via the rotation sensing device100, such as one described above with respect toFIGS. 1A-1D, 2A, 2B, and3A-3D. In some embodiments, the rotation sensing device100may be a metering device, such as a gas meter, parking meter, water meter, electricity meter, etc. One or more steps of the process400may be implemented by a processing device, such as the processing device120or other computing device, and may be implemented as computer-readable code. For example, one or more steps of the process400may be implemented using hardware, software, firmware, non-transitory computer readable media having instructions stored thereon, or a combination thereof and may be implemented in one or more computer systems or other processing systems. The process400may start at any step or may end after any step.

At step402, the magnet102of the rotation sensing device100may generate a magnetic field. At step404, the flux conductor108of the rotation sensing device100may rotate relative to the fixed magnet102. The flux conductor108may alter the generated magnetic field based on rotation of the flux conductor108. For example, the flux conductor108may provide a low magnetic resistance flux path for the generated magnetic field to follow, such as responsive to the flux conductor108being aligned with the magnetic field generated by the magnet102.

In some embodiments, the flux conductor108may rotate to a position such that may enhance a flux path between the magnet102and a magnetic field sensor104may be enhanced. In some embodiments, the flux conductor108may rotate to a position such that might not enhance or might no longer enhance a flux path between the magnet102and a magnetic field sensor104.

At step406, the magnetic field sensor may sense the magnetic field strength of the generated magnetic field. At step408, the magnetic field sensor104may generate a signal based on the sensed magnetic field, such as via the circuit board118and/or processing device120. At step410, the processing device120(or other device) may determine or measure a quantity based on the signal generated by the magnetic field sensor104.

While various exemplary embodiments of the disclosed system and method have been described above it should be understood that they have been presented for purposes of example only, not limitations. For example, various embodiments have been described in the context of a meter that is used to measure consumption of a commodity. It will be appreciated, however, that the principles disclosed herein are not limited to such, but rather can be applied in any context where sensing of rotation is desirable. Modifications and variations are possible in light of the above teachings or may be acquired from practicing of the disclosure, without departing from the breadth or scope.