Magnetic sensor system

Provided herein are improved magnetic sensor systems for use in linear measurement systems. A magnetic sensor can be positioned offset from a center line positioned between two magnets. The two magnets can be oriented so as to provide opposite polarities. As the magnetic sensor traverses a path parallel to the magnets and parallel to the center line, the sensor can detect a magnetic flux density provided by the two magnets. Offsetting the magnetic sensor from the center line can improve the linear range of the magnetic sensor, thereby improving the reliability and accuracy of an output signal generated by the magnetic sensor based on the detected magnetic flux density.

FIELD OF THE DISCLOSURE

This disclosure relates generally to the field of magnetic sensor systems, more particularly, to linear measurement systems using magnetic sensors.

BACKGROUND OF THE DISCLOSURE

In many conventional measurement systems, magnetic sensors such as Hall sensors are used. For example, for a conventional tension sensor for a seat buckle, a Hall sensor and two magnets can be used to generate an output signal indicative of varying levels of tension. Typically, in such systems, the Hall sensor is positioned in the center of two magnets. The Hall sensor travels linearly along a center line between the two magnets as tension is applied and generates the output signal.

The linearity of many conventional magnetic sensor systems—including many conventional tension sensors—is limited by the arrangement of the sensor and the magnets. Specifically, the linearity of the sensor is often limited to positions very near the midpoints of the two magnets. This limited linearity range in such conventional systems limits the reliability and accuracy of measurements made by the magnetic sensor, thereby limiting the usefulness of such conventional systems.

To improve the linear range of conventional magnetic sensor systems, larger magnets can be used. However, the use of larger magnets can introduce significant size burdens that must be accounted for during the design and use of such systems. In many instances, employing larger magnets prevents conventional magnetic sensor systems from fitting into tight spaces or restricted spaces where such systems are typically used.

SUMMARY

Accordingly, there is a need for magnetic sensor systems that can provide extended linear ranges without imposing the need for larger magnets.

Various embodiments are generally directed to an improved magnetic sensor system with an extended linear range. Various embodiments provide an improved magnetic sensor system with an extended linear range that can be applied to any measurement system including linear displacement or linear distance measurement systems. Various embodiments provide a magnetic sensor system that includes one or more sensors and two or more magnets. Various embodiments provide a magnetic sensor system including a sensor that is offset from a center line positioned between two magnets having opposite polarities. Various embodiments provide a magnetic sensor system including a first sensor that is offset from a center line positioned between two magnets having opposite polarities and a second sensor offset from the center line in a direction opposite to the first sensor.

DETAILED DESCRIPTION

FIG. 1illustrates a conventional magnetic sensor system100. The conventional magnetic sensor system100includes a first magnet102, a second magnet104, and a magnetic sensor106. The first magnet102and the second magnet104can be separated by a distance108. As shown inFIG. 1, the first magnet102and the second magnet104can be oriented in opposite manners relative to one another with respect to north and south poles of each of the first and second magnets102and104. As such, the first magnet102and the second magnet104can be considered to be of opposite polarity.

The magnetic sensor106can be positioned in the middle between the first magnet102and the second magnet104. The magnetic sensor106can traverse a path110. The path110can be parallel to the first and second magnets102and104. The path110can bisect the distance108such that the sensor106is separated from each of the first and second magnets102and104by the same distance.

The magnetic sensor106can detect a magnetic flux density provided by the first and second magnets102and104. The magnetic flux density provided by the first and second magnets102and104can vary along the path110. Accordingly, as the sensor106traverses the path110, the sensor106can detect changes in the magnetic flux density. The sensor106can generate a signal based on the detected magnetic flux density and/or changes thereto.

The range of linearity of a signal generated by the sensor106is significantly limited by the arrangement of the conventional magnetic sensor system100. As such, in the conventional magnetic sensor system100, the sensor106can only reliably output a linear signal when it is confined to positions near the midpoint of the first and second magnets102and104. This limited range of linearity greatly reduces the ability of the conventional magnetic sensor system100to reliably provide signals based on measured magnetic flux density over needed distances. To improve the range of linearity, the sizes of the first and second magnets102and104can be increased. However, in doing so, movement of the sensor106may become overly restricted and/or the conventional magnetic sensor system100may become too large to be used in confined areas where magnetic sensor systems are typically used.

FIG. 2illustrates an exemplary magnetic sensor system200. The exemplary magnetic sensor system200includes a first magnet202, a second magnet204, and a magnetic sensor206. The magnetic sensor206can be any type of sensor for detecting or measuring magnetic flux density such as, for example, a Hall sensor.

As shown inFIG. 2, the first and second magnets202and204are separated by a gap distance208. The first and second magnets202and204can be of the same size and shape. As an example, the first and second magnets202and204can be cylindrical magnets or can be rectangular magnets. The first and second magnets202and204can be oriented or positioned parallel to one another.

To foster explanation, orientation axes210is provided inFIG. 2. The orientation axes210include an “x” axis and a “y” axis as shown which, as an example and for purposes of illustration only, can be considered as representing horizontal and vertical directions, respectively. The first and second magnets202and204can be horizontally separated as shown relative to the “x” axis. The magnets202and204can be also be oriented vertically relative to the “y” axis.

Contours212can represent a component of the magnetic flux density provided by the first and second magnets202and204. As an example, the contours212can represent variations in magnitude of the “x” component of the magnetic flux density provided by the first and second magnets202and204(relative to the orientation axes210). The sensor206can measure variations in the magnetic flux density represented by the contours212. That is, the sensor206can measure the “x” component of the magnetic flux density represented by the contours212.

As an example, the first and second magnets can be cylindrical magnets of the same size having diameters of approximately 4.4 millimeters (mm) and lengths of 6 mm. Further, the gap distance208between the magnets can be approximately 5.0 mm. Additionally, the contours212can represent the x component of the magnetic flux density that ranges from −0.4 Tesla (T) to 0.4 T (such that contours of the x component of the magnetic flux density having magnitudes larger than 0.4 T or smaller than −0.4 T are not shown). The “+” and “−” signs shown inFIG. 2can represent positive and negative values of the x component of the magnetic flux density provided by the first and second magnets202and204, respectively.

As shown inFIG. 2, the first and second magnets202and204can be oriented opposite to one another. Specifically, the first magnet202can be oriented such that its north pole is oriented upwards (relative to the orientation axes210) and the second magnet204can be oriented such that its north pole is oriented downwards (relative to the orientation axes210). The orientation of the first magnet202as shown inFIG. 2can be considered a first orientation or state and the orientation of the second magnet204as shown inFIG. 2can be considered a second orientation or state. As such, the first magnet202can be associated with providing (or oriented according to) a first polarity and the second magnet204can be associated with providing (or oriented according to) a second polarity. Accordingly, the first and second magnets202and204as shown inFIG. 2are oriented with opposite polarities relative to one another.

FIG. 2further shows a center line or path214, a left line or path216, and a right line or path218. The “left” and “right” lines216and218are considered to be oriented as such for illustration and explanation purposes only (e.g., relative to the orientation axes210). The center line214can be parallel to the first and second magnets202and204. As an example, the center line214can be parallel to a central vertical axis of the first magnet202and the second magnet204. The center line214can be positioned in the center between the first and second magnets202and204such that a distance between the center line214and the first magnet202is equal to the distance between the center line214and the second magnet204(e.g., the center line214can bisect the gap distance208).

The left line216can be offset from the center line214. Specifically, the left line216can be offset from the center line214by a distance220. The left line216can be positioned closer to the first magnet202relative to the center line214as shown inFIG. 2.

Similarly, the right line218can be offset from the center line214. Specifically, the right line218can be offset from the center line214by a distance222. The right line218can be positioned closer to the second magnet204relative to the center line214as shown inFIG. 2.

The offset distances220and222can be any distance. The offset distances220and222can be, as an example, equal such that the left line216is offset from the center line214by an amount that is equal to the offset between the right line218and the center line214. The left line216and the right line218can be parallel to the center line214and so also parallel to the first and second magnets202and204(e.g., parallel to a central vertical axis of the first magnet202and a central vertical axis of the second magnet204). As an example, the offset distance220can be approximately 1.25 mm and the offset distance222can also be approximately 1.25 mm.

For the exemplary magnetic sensor system200, the sensor206can be positioned along the path shown by the right line218(as shown inFIG. 2) or can be positioned along the path shown by the left line216. As such, the left and right lines216and218can each be considered sensor lines. The sensor lines216and218are arranged such that when the sensor206is positioned on either sensor line216or218, the sensor206would be closer to one of the two magnets202and204. For example, when the sensor206is positioned on the sensor line216, the sensor206will remain closer to the first magnet202than the second magnet204for all positions along the sensor line216. Likewise, when the sensor206is positioned on the sensor line218, the sensor206will remain closer to the second magnet204than the first magnet202for all positions along the sensor line218.

To measure or detect the magnetic flux density (or changes thereto) provided by the first and second magnets202and204, the sensor206can be moved along either of the sensor lines214and216while the first and second magnets202and204remain in a fixed or stationary position. Alternatively, the sensor206can be positioned on either of the sensor lines216or218and can remain in a fixed or stationary position as the first and second magnets202and204are moved in unison. Under such a scenario, the first and second magnets202and204can move along a path that is parallel to the sensor lines216and218(along the central vertical axes of the first and second magnets202and204).

As an example, the positions of the first and second magnets202and204can be fixed relative to the sensor206. Further, the sensor206can be positioned to traverse the path indicated by the sensor line218. As the sensor206traverses the path indicated by the sensor line218, the sensor206can measure or detect the magnetic flux density provided the first and second magnets202and204(e.g., the x component of the magnetic flux density). The sensor206can generate or produce an electrical signal based on the detected magnetic flux density. For example, the sensor206can generate a signal of relatively lower magnitude corresponding to a relatively weaker detected magnetic flux density and can generate a signal of relatively higher magnitude corresponding to a relatively stronger detected magnetic flux density. As shown inFIG. 2, as an example, the sensor206can detect negative values of the magnetic flux density at the lower end of the sensor line218and can detect positive values of the magnetic flux density at the upper end of the sensor line218(e.g., relative to the orientation axes210).

The sensor206, when positioned on one of the sensor lines216or218, can have an extended linear range as compared to the sensor206being positioned on the center line214(or in comparison to the sensor106of the conventional magnetic measurement system100). The extended linear range of the sensor206provided by being positioned on one of the sensor lines216or218is provided whether the sensor206is fixed relative to movement of the first and second magnets202and204or whether the sensor206is moved relative to a fixed positioning of the first and second magnets202and206. As mentioned above, the sensor206can measure the x component of the magnetic flux density/magnetic fields as shown inFIG. 2.

The sensor lines216and218can provide an extended linear range for the sensor206relative to the center line214by being oriented to traverse or overlap larger regions of the contours212that have gaps or distances between the contours212that are the same or similar sizes. The contours212can represent different magnitudes of the magnetic flux density provided by the first and second magnets202and204(e.g., the x component of the magnetic flux density). Accordingly, gaps or distances between adjacent contours212can represent a difference in magnitude between adjacent contours212. When the gaps between adjacent contours212remain fixed or are of approximately the same size, a signal generated by the sensor206can remain linear or more closely linear over such regions as compared to over regions where the gap distances vary.

As an example, a contour gap distance224is shown inFIG. 2for the center line214. As can be seen inFIG. 2, the contour gap distance224(shown inFIG. 2as “ΔY”) remains fairly uniform in a central region along the center line214between the first and second magnets202and204. However, at the top and bottom ends of the center line214, the gaps between the contours212increase such that the contour gap distance224varies considerably. Since the linear range of a sensor depends on the gap distance224remaining approximately uniform, a sensor traversing the center line214would have a very limited linear range.

In contrast, the gaps between the contours212traversed by the sensor lines216and218remain approximately uniform over a longer distance, particularly at the ends of the sensor lines216and218compared to the center line214. That is, gaps between contours212at the ends of the sensor lines216and218remain more uniform as compared to the center line214. As a result, when the sensor206measures magnetic flux density along one of the sensor lines216or218, the linear range of the sensor is extended in comparison to measuring magnetic flux density long the center line214.

Accordingly, the magnetic sensor system200provides an enhanced linear magnetic measuring system. By positioning the sensor206offset from the center line214, a linear range of the sensor206—e.g., in terms of the relationship between detecting magnetic flux density and generating an output signal indicative of the detected magnetic flux density—can be extended, in comparison to the conventional magnetic sensor system100.

FIG. 3illustrates an extended linear range provided by the exemplary magnetic sensor system200. Specifically,FIG. 3shows measured magnetic flux density (e.g., the x component of the magnetic flux density) relative to distance along the center line214and the sensor lines216and218. Plot302can represent measured magnetic flux by a sensor positioned along the center line214. A linear range of the plot302is indicated by first end306-A and second end306-B, and represents the linear range of a sensor positioned on the center line214. In comparison, plot304can represent measured magnetic flux by a sensor (e.g., the sensor206) positioned along either sensor line216or218. The linear range of the plot304is indicated by first end308-A and second end308-B, and represents the linear range of a sensor (e.g., the sensor206) positioned on either sensor lines216or218. The plots302and30can be based on the exemplary cylindrical magnet shapes and sizes (e.g., cylindrical with diameters of 4.4. mm and lengths of 6 mm), exemplary gap distance208(5.0 mm), and exemplary offset distances220and222(1.25 mm each) discussed above.

As shown inFIG. 3, the linear range of plot304is larger or longer than the linear range of the plot302. Specifically, the linear range of a sensor positioned on one of the sensor lines216or218is greater (e.g., in terms of distance) than the linear range of a sensor positioned on the center line214. Consequently, a sensor positioned on either sensor line216or218can provide a signal indicative of the magnetic flux density that remains linear over a longer distance range, thereby improving the reliability, usefulness, and/or accuracy of a magnetic flux density measurement compared to such measurement made by a sensor along the center line214. For the example cylindrical magnets sizes, gap distance, and offset distances, the linear range of the sensor206when positioned on the sensor line216or218can be extended by approximately 25% compared to the linearity range of a sensor provided by the conventional magnetic sensor system100(e.g., when the sensor is positioned along the center path214).

The magnetic sensor system200can be used in any measurement system based on producing signals indicative of magnetic field density changes. The magnetic field density changes can be converted into useful electrical signals which can, for example, inform the weight of drivers or passengers of vehicles or can indicate the tension of a seat belt (e.g., whether the seat belt is buckled or not or is too tight or too loose). In general, the sensor206shown inFIG. 2can generate or provide a signal based on detected magnetic flux density that depends on the orientation of the sensor206relative to the first and second magnets202and204to provide useful information about such positioning. As such, the magnetic measurement system200(and any magnetic measurement system of the present disclosure as described herein) can be used in any distance or displacement measurement system.

FIG. 4illustrates a second exemplary magnetic sensor system400. The second exemplary magnetic sensor system400, as shown, is similar to the first exemplary magnetic sensor system200but includes a second sensor402. The second sensor402is positioned along the sensor line216. The second sensor402can be any magnetic sensor including, for example, a Hall sensor.

The magnetic sensor system400can function and operate similarly to the magnetic sensor system200. In the magnetic sensor system400, however, each of the sensors206and402can measure or detect the magnetic flux density provided by the magnets202and204. Specifically, the first sensor206and the second sensor402can each measure magnetic flux density such that the measured x components of the magnetic flux density can be added and the measured y components of the magnetic flux density can be canceled out.

In general, for many magnetic sensor systems, it is desirable to detect and measure one component of a magnetic flux density (e.g., the x component) while disregarding a second component of the magnetic flux density (e.g., the y component). For example, accurate measurement of the x component of the magnetic flux density can be adversely affected by undesired detection of the y component of the magnetic flux density. In various magnetic sensor systems, misalignments between the magnets and/or the magnetic sensors (e.g., during fabrication or from wear and tear over time) can cause a magnetic sensor to pick up or detect the undesired y component of the magnetic flux density.

The magnetic sensor measurement system400mitigates this risk by providing the two sensors206and402. As an example, the sensors206and402can each measure the magnetic flux density of the environment provided by the magnets202and204. Further, the x components of the measured magnetic flux densities as detected by the sensors206and402can be measured additively while the y components of the magnetic flux densities as detected by the sensors206and402can be cancelled out.

For example, the magnetic flux density measured by the sensor206can have a first component and a second component, corresponding to a desired x component measurement and an undesired y component measurement, respectively. Further, the magnetic flux density measured by the sensor402can also have a first component and a second component, corresponding to a desired x component measurement and an undesired y component measurement, respectively. With the magnetic sensor system400, these first measured components (the x components of the detected magnetic flux density) can be measured additively while the second measured components (the y components of the detected magnetic flux density) can be canceled out (e.g., by subtracting the y component measurement from the sensor206from the y component measurement from the sensor402). In doing so, the magnetic sensor measurement system400can provide improved magnetic flux density measurements.

FIG. 5illustrates possible variations in the positions of the sensors206and/or402depicted in magnetic measurement systems200and400.FIG. 5shows a first plane502, a second plane504, and a third plane506. The planes502-506can be perpendicular to the orientation axes210(shown inFIG. 5for illustrative purposes). That is, the planes502-506can be perpendicular to a plane that bisects the first and second magnets202and204and contains the center line214as shown, for example, inFIGS. 2 and 4. The plane502can correspond to the center line214. The plane504can correspond to the left sensor line516. The plane506can correspond to the right sensor line218. Specifically, the planes502-506can indicate a range of positioning of the center line214and sensor lines516and518, respectively, that is perpendicular to the orientation axes210(and therefore perpendicular to a plane that bisects the first and second magnets202and204and contains the center line214as shown inFIGS. 2 and 4).

For purposes of illustration, the right sensor line218is shown for reference. The plane506can include the right line218. The plane506, as mentioned above, can be perpendicular to the orientation axes210. As an example, the plane506can represent a possible variation in the placement of the right sensor line218along a “z” direction. The plane506—representing variation in a “z” direction—can be perpendicular to a plane that bisects the first and second magnets202(e.g., and includes a central vertical axis of each of the magnets202and204) and is parallel to the orientation axes210(and can include the center line214). According to the present disclosure, the sensor206can be offset along the plane506from the right sensor line218. For example, the sensor206can be offset by a distance510along an offset line508. Alternatively, as an example, the sensor206can be offset by a distance in the opposite direction along an offset line512. The offset distance510can be any distance such as, for example, 1.25 mm.

Overall,FIG. 5is intended to show variations of the positioning of the sensor206and/or402in the magnetic measurement systems200and400in three dimensions (and for further magnetic sensor systems of the present disclosure described below). In general, the sensors206and402can be offset in a direction that is perpendicular to a plane that bisects the first and second magnets202and204and is parallel to the orientation axes210. As an example, the sensors206and/or402can be offset along this third axis by an amount that is approximately equal to or less than the offset distances220and/or222. For example, for sensor206, the offset distance222can be 1.5 mm and the offset distance510can also be 1.25 mm. As such, the sensor206can be positioned along the sensor line508(or sensor line512) for measuring magnetic flux density. The positioning of the sensor402can be similarly varied. As shown, the plane506can contain the lines508,218, and512. As such, the plane506can be perpendicular to a plane containing the lines214,216, and218as depicted, for example, inFIGS. 2 and 4.

FIG. 6illustrates a third exemplary magnetic measurement system600. As shown inFIG. 6, the magnetic measurement system600is similar to the magnetic measurement systems200and functions similarly. With the magnetic measurement system600, however, the first and second magnets202and204are oriented differently than the orientation between the first and second magnets202and204as shown inFIG. 2for the magnetic measurement system200. Specifically, the first magnet202is oriented according to a third orientation or state such that its north pole is positioned closer to the sensor line216relative to its south pole. Similarly, the second magnet204is oriented according to a fourth orientation or state such that its north pole is positioned closer to the sensor line218relative to its south pole.

The positioning and orientation of the first and second magnets202and204as shown inFIG. 6results in the first and second magnets202and204having opposite polarities. Further, in contrast to the magnetic measurement system200, the sensor206as depicted inFIG. 6can measure variations in the magnetic flux density along a y component (relative to the orientation axes210). The orientation of the magnets202and204as shown inFIG. 6is such that the north and south poles of the magnets are oriented parallel to the sensor line214. In contrast, the orientation of the magnets202and204as shown inFIG. 6is such that the north and south poles of the magnets are oriented perpendicular to the sensor line214. In both arrangements, the magnets202and204can be considered as arranged having different polarities.

The magnetic flux density provided by the magnets202and204as oriented inFIG. 6can vary from the magnetic flux density provided by the magnets202and204as oriented inFIG. 2. Specifically,FIG. 2illustrates the x component of the magnetic flux density whileFIG. 6illustrates the y component of the magnetic flux density. As such, the magnetic flux density variations provided by the magnets202and204as depicted inFIG. 6are represented by contours610(corresponding to the contour212shown inFIG. 2). As an example, the contours610can represent the y component of the magnetic flux density provided by the magnets202and204ofFIG. 6that ranges from −0.4 T to 0.4 T (such that contours of the y component of the magnetic flux density having magnitudes larger than 0.4 T or smaller than −0.4 T are not shown).

The shapes and sizes of the first and second magnets202and204, the gap distance208, the offset distances220and222, as well as other features of the magnetic measurement system600can vary as discussed in relation toFIG. 2. As an example, the magnets202and204can be cylindrical magnets having diameters of approximately 4.4 mm and lengths of approximately 6 mm, with a gap distance2085.0 mm, and with offset distances220and222of 1.5 mm each.

As with the magnetic measurement system200, the magnetic measurement system600can also provide for an enhanced or extended linear range of the sensor206. This can be illustrated based on gap distance604(shown inFIG. 6as “ΔY”). As can be seen inFIG. 6, the gap distance604remains fairly uniform in a central region along the center line214between the first and second magnets202and204. However, at the top and bottom ends of the center line214, the gaps between the contours602increase such that the gap distance604varies considerably. In contrast, the gaps between the contours602traversed by the sensor lines216and218remain approximately uniform over a longer range, particularly at the ends of the sensor lines216and218compared to the center line214. That is, gaps between contours602at the ends of the sensor lines216and218remain more uniform as compared to the center line214. As a result, when the sensor206measures magnetic flux density along one of the sensor lines216or218, the linear range of the sensor is extended in comparison to measuring magnetic flux density along the center line214.

FIG. 7illustrates an extended linear range provided by the exemplary magnetic sensor system600. Specifically,FIG. 7shows measured magnetic flux density (e.g., the y component of the magnetic flux density) relative to distance along the center line214and the sensor lines216and218. Plot702can represent measured magnetic flux by a sensor positioned along the center line214. A linear range of the plot702is indicated by first end706-A and second end706-B, and represents the linear range of a sensor positioned on the center line214. In comparison, plot704can represent measured magnetic flux by a sensor (e.g., the sensor206) along either sensor line216or218. The linear range of the plot704is indicated by first end708-A and second end708-B, and represents the linear range of a sensor (e.g., the sensor206) positioned on either sensor line216or218.

As shown inFIG. 7, the linear range of plot704is larger or longer than the linear range of the plot702. Specifically, the linear range of a sensor positioned on one of the sensor lines216or218is greater (e.g., in terms of distance) than the linear range of a sensor positioned on the center line214. Consequently, a sensor positioned on either sensor line216or218can provide a signal indicative of the magnetic flux density that remains linear over a longer distance range, thereby improving the reliability, usefulness, and/or accuracy of a magnetic flux density measurement compared to such measurement made by a sensor along the center line214. For the example cylindrical magnets sizes, gap distance, and offset distances stated above in relation toFIG. 6, the linear range of the sensor206when positioned on the sensor line216or218can be extended by approximately 30% compared to the linearity range of a sensor provided by the conventional magnetic sensor system100(e.g., when the sensor is positioned along the center path214).

FIG. 8illustrates a fourth exemplary magnetic sensor system800. The fourth exemplary magnetic sensor system800, as shown, is similar to the third exemplary magnetic sensor system600but includes a second sensor802. The second sensor802is positioned along the sensor line216. The second sensor802can be any magnetic sensor including, for example, a Hall sensor. By including two sensors, the fourth exemplary magnetic sensor system800can improve detection of a first component of a magnetic flux density provided by the first and second magnets202and204(e.g., the y component as shown in relation toFIG. 8) while reducing unwanted effects from detection of a second component of the magnetic flux density (e.g., the x component as shown in relation toFIG. 8), as explained in relation to the magnetic sensor system400.

The sensors206and802can each measure the magnetic flux density of the environment provided by the magnets202and204. Specifically, the y components of the magnetic flux densities as detected by the sensors206and802can be measured additively while the x components of the magnetic flux densities as detected by the sensors206and802can be cancelled out. For example, the magnetic flux density measured by the sensor206can have a first component and a second component, corresponding to a desired y component measurement and an undesired x component measurement, respectively. Further, the magnetic flux density measured by the sensor802can also have a first component and a second component, corresponding to a desired y component measurement and an undesired x component measurement, respectively. With the magnetic sensor system800, these first measured components (the y components of the detected magnetic flux density) can be measured additively while the second measured components (the x components of the detected magnetic flux density) can be canceled out (e.g., by subtracting the x component measurement from the sensor206from the x component measurement from the sensor802). In doing so, the magnetic sensor measurement system800can provide improved magnetic flux density measurements.

FIG. 9illustrates exemplary results for a magnetic sensor system of the present disclosure. A plot902shows the relationship between a signal generated by a magnetic sensor and a vertical displacement of the sensor in relation to two identical magnets. The signal generated by the magnetic sensor was based on the magnetic flux density detected by the sensor. To generate the exemplary results, a Hall sensor was placed 0.22 mm off from a center line separating the two identical magnets and 0.55 mm of from the plane passing through the two centers of the magnets. The sensor was moved relative to the magnets. A signal generated by the sensor was recorded for various vertical displacements of the sensor relative to the two magnets, resulting in plot902. As shown inFIG. 9, the plot902is linear, indicating that the output signal generated by the test sensor is linear as the sensor traverses the magnetic flux density provided by the test magnets.

FIG. 10illustrates an exemplary arrangement of multiple magnets500that can be used with the magnet sensor systems of the present disclosure as described herein. As shown inFIG. 10, four magnets are shown: a first magnet1002, a second magnet1004, a third magnet1006, and a fourth magnet1008. The magnets1002-1008can be of approximately the same size and shape. As an example, each of the magnets1002-1008can be cylindrical magnets. Alternatively, the magnets1002-1008can be rectangular magnets. As further shown inFIG. 5, exemplary orientation axes1010is also shown for illustrative and explanatory purposes. The orientation axes include “x”, “y”, and “z” directions to illustrate the three dimensional arrangement of the magnets1002-1008.

As shown inFIG. 10, each of the magnets1002-1008are oriented vertically (e.g., relative to the y axis of the orientation axes1010), but are not so limited. The first magnet1002and the second magnet1004are oriented similarly such that the north poles of the magnets1002and1004are positioned above the south poles of the magnets1002and1004. The third magnet1006and the fourth magnet1008are also oriented similarly such that the south poles of the magnets1006and1008are positioned above the north poles of the magnets1006and1008. The first and second magnets1002and1004can be considered to be oriented in a first manner to provide a first polarity and the and the third and fourth magnets1006and1008can be considered to be oriented in a second manner to provide a second, opposite polarity.

When viewed along the z axis direction of the orientation axes1010, the second magnet1004can correspond to the first magnet202and the fourth magnet1008can correspond to the second magnet204as depicted, for example, inFIG. 2. The first magnet1002and the third magnet1006can then be seen as similarly oriented magnets positioned behind the magnets1004and1008.

The arrangement1000shown inFIG. 10can be used with the magnetic measurement systems described herein. For example, the magnetic measurement systems200and400can be modified to include the arrangement1000. Further, as an example, by adjusting the orientation of the magnets1002-1008as described herein, the magnetic measurement systems600and800can be modified to include the arrangement1000(e.g., by having the north poles of the magnets1002-1008oriented horizontally and pointing to one another). The arrangement1000can be extended to additional magnets and is not limited to the four magnets as shown. Further, in accordance with the present disclosure, one or more sensors can be positioned in the center of the magnets1002-1008such that the one or more sensors are offset from a central vertical axis that is equidistant to each of the magnets1002-1008. In doing so, a linear range of the one or more sensors can be enhanced over conventional positioning of magnetic sensors relative to multiple magnetic arrangements in accordance with the principles described herein.

In accordance with the present disclosure, the gap distance between the two or more magnets (e.g., in the systems described herein) can be based on the size of the magnets used in the system. Further, any offset of a sensor from a center line (e.g., either in the same plane as the center line or perpendicular thereto) can be based on the size of the magnets and/or the size of the gap distance, thereby allowing the one or more sensor lines to be positioned so as to extend a linear range of a sensor used in the systems described herein.

While the present disclosures references certain embodiments, numerous modifications, alterations and changes to the described embodiments are possible without departing from the sphere and scope of the present disclosure, as defined in the appended claim(s). Accordingly, it is intended that the present disclosure not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof.