JP3198075U6 - Magnet device and position detection system - Google Patents

Abstract

A magnet apparatus and a position detection system for generating a magnetic flux density change / magnetic field change that more accurately reflect an angular position of a rotatable shaft.
A position detection system includes a magnet device, a detection device, a processing circuit, and a rotating shaft. The detection device 104 is electrically connected to the processing circuit 106 via a connection 109. The magnet device 102 is introduced on the rotating shaft 108 and is suitable for rotating with the rotating shaft 108 about the axial center of the rotating shaft 108. The detection device 104 is located above the magnet device 102 and is separated from the magnet device 102 by a distance D (183). When the magnet device 102 rotates about the axial center of the rotating shaft 108, the magnet device 102 A change in magnetic flux density at the position of the detection device 104 (ie, the detection position) is generated, and a change in the magnetic field is further generated.
[Selection] Figure 1A

Description

  The present disclosure relates generally to magnet devices and position detection devices. More particularly, the present invention relates to a magnet device used in a position detection device for detecting an angular position range of a rotatable shaft.

  It is known in the industry to use multiple position sensing devices for detecting multiple angular positions of a rotatable shaft.

  Traditionally, mechanically contacted position sensing devices are used to detect the angular position of a rotatable shaft. However, mechanically contacted position sensing devices have drawbacks including mechanical wear, low angular accuracy and reliability, and lack of diagnostic capabilities.

  There have been proposals to use an electronic detection system to generate a binary signal to reflect the angular position of the rotatable shaft. In particular, the electronic detection system includes a detection device for generating an analog electronic signal in response to rotation of the rotatable shaft, the electronic detection system further comprising a binary signal for indicating the angular position of the rotatable shaft. Process the analog signal to generate More particularly, the magnet device is fixed on the rotatable shaft and is configured to rotate with the rotatable shaft. The magnet device causes a magnetic flux density change / magnetic field change to the detection device while it rotates about a rotatable shaft. The detection device generates an analog electrical signal in response to the magnetic flux density change / magnetic field change, which is then converted to a binary signal.

  Accordingly, there is a need to provide an improved magnet arrangement for generating magnetic flux density changes / magnetic field changes that more accurately reflect the angular position of the rotatable shaft.

  There is another need to provide an improved detection device to generate binary state signals to more accurately reflect the angular position of the rotatable shaft using magnetic flux density changes / magnetic field changes. To do.

In a first aspect, the present disclosure provides a magnet apparatus for providing a magnetic field strength change / magnetic field change with respect to a detection location. The magnet apparatus centralizes / condenses the magnetic member mounted on the rotatable shaft and configured to rotate with the rotatable shaft (108) and the magnetic field strength change / density of the magnetic field change. A magnetic flux density concentrator for
The magnet member generates the magnetic field strength change / magnetic field change with respect to the detection position when the magnet member is rotating around the rotatable shaft.

According to the first aspect, the magnet device is used together with the detection device having the detection position where the detection element is positioned. Here, the detection device includes the detection element having a front surface and a back surface,
The magnetic flux density concentrator includes a magnetic flux density concentrator element positioned adjacent to the back surface of the sensing element.

According to the first aspect of the magnet device,
The magnet member has a first side surface and a second side surface located on opposite sides of the magnet member,
The magnetic flux density concentrator further includes first and second magnetic flux density concentrator elements,
The first magnetic flux density concentrator element is positioned adjacent to the first side of the magnet member;
The second magnetic flux density concentrator element is positioned adjacent to the second side surface of the magnet member.

According to a second aspect, the present disclosure provides a position detection system for generating a binary state signal for indicating an angular position range relative to a rotatable shaft. The position detection system is
Comprising a magnet device as described in the first aspect, wherein the magnet device generates a magnetic field strength change / magnetic field change;
The position detection system is
A detection device for generating an electrical signal in response to the magnetic field strength change / magnetic field change;
And a processing circuit for generating the binary state signal in response to the electrical signal.

According to the second aspect of the position detection system,
The processing circuit includes a threshold circuit for providing a threshold voltage on a bell-shaped function curve, and an indication circuit,
The indicating circuit generates a first signal state when the voltage of the detected electric signal is larger (or smaller) than the threshold voltage, and the voltage of the detected electric signal is the threshold value. When it is smaller (or larger) than the voltage, a second signal state is generated.

According to the second aspect of the position detection system,
The threshold voltage and the bell-shaped function curve are such that when the bipolar magnet rotates 360 degrees around the rotatable shaft, the position is detected in response to the magnetic flux density change / magnetic field change in one dimension. It is calibrated before the system is installed.

According to the second aspect,
To compensate for variations in operating conditions including gap deformation and temperature and parameter variations in the components used by monitoring and updating the maximum and minimum peaks of the electrical signal that fit the bell-shaped function curve. An adjustment circuit for adjusting the binary state signal is further provided.

  By providing a magnet device and position sensing system, the present disclosure overcomes the drawbacks described above in existing technology.

  The present invention will be described with reference to the accompanying drawings.

1 illustrates a position detection system 100 according to the present disclosure showing a side view of a rotatable shaft 108 in the position detection system 100. FIG. 1B illustrates the position detection system 100 of FIG. 1A, showing a top view of the rotatable shaft 108 illustrated in FIG. 1A. 1B illustrates a position detection system 100 showing a cross-sectional view of the rotatable shaft 108 of FIG. 1B along line AA in FIG. 1B. 2 illustrates an exemplary embodiment of the magnet device 102 and the detection device 104 illustrated in FIGS. (A)-(C) illustrate three embodiments of the magnet device 102 and detection device 104 illustrated in FIGS. 1A-C, according to the present invention. (A)-(C) illustrate three additional embodiments of the magnet devices 102A-C and detection devices 104A-C illustrated in FIGS. 1A-C according to the present invention. One embodiment of the processing circuit 106 in the position detection system 100 is illustrated in more detail. Another embodiment of the processing circuit 106 in the position detection system 100 is illustrated in more detail. The processing unit 504 illustrated in FIG. 5A is illustrated in more detail. (A) illustrates a bell-shaped function curve 702 reflecting changes in magnetic flux density / magnetic field generated by the magnet 204 illustrated in FIG. 2, and (B) illustrates FIGS. 3 (A), (B), and 4. Magnetic flux density produced by a magnet (304A, 304B, 404A or 404B) and one or more magnetic flux density concentrators (308A1, 308A2; 308C1, 308C2; 309B; or 309C) illustrated in (A), (B). A bell-shaped function curve 706 reflecting changes / magnetic field changes is illustrated. (A) illustrates a bell-shaped function curve 802 that reflects the voltage output detected by the detection element 202 illustrated in FIG. 2, and (B) is illustrated in FIG. 3A, FIG. 3B, 4A, or 4B. The bell-shaped function curve 806 that reflects the voltage output detected by the detection element (302A or 302B) is illustrated, and (C) shows the first signal based on the bell-shaped function curve 806 in the calibration (or simulation) process. FIG. 6 illustrates a method for forming a binary state signal 107 having a state and a second signal state. (A), (B) are either a positive binary state signal 107 or a negative binary state signal 107 ′ to indicate the rotational range for the rotatable shaft 108 illustrated in FIGS. The use of is illustrated. The output 111 of the processing circuit 106 illustrated in FIGS. 1A-C illustrates an engine control system 900 that is used to control an engine in an automobile.

  Reference will now be made to the embodiments, examples of which are illustrated in the accompanying drawings. In the detailed description of the embodiment, for example, “top”, “bottom”, “above”, “below”, “left”, “right”. Terms such as direction are used with reference to the direction of the drawing or drawings described. Because components of embodiments of the present disclosure are positioned in many different directions, the terminology terms are used for illustrative purposes and are not limited by the terms. Wherever possible, the same or similar reference numbers and symbols are used throughout the drawings to refer to the same or like parts.

  FIG. 1A illustrates a position detection system 100 according to the present disclosure showing a side view of the rotatable shaft 108 in the position detection system 100.

  In FIG. 1A, the position detection system 100 includes a magnet device 102, a detection device 104, a processing circuit 106, and a rotatable shaft 108. The detection device 104 is electrically connected to the processing circuit 106 via a link 109, and the magnet device 102 is mounted on the rotatable shaft 108 and of the shaft 112 (shown in FIG. 1C) of the rotatable shaft 108. It is configured to rotate around with the rotatable shaft 108. The detection device 104 is positioned upward and separated from the magnet device 102 by a distance (or gap) D (183). When rotating about the axis 112 of the rotatable shaft 108, the magnet device 102 can cause a change in magnetic flux density relative to the position (or detection position) where the detection device 104 is located, which in turn causes a magnetic field change. be able to. The detection device 104 may generate an electrical signal (eg, PWM, SENT, etc.) when it receives a magnetic flux density change / magnetic field change from the magnet device 102. As in the exemplary embodiment, the detection device 104 may include a Hall effect circuit for generating an electrical signal in response to magnetic field changes caused by magnetic flux density changes. The detection device 104 supplies the detected electrical signal to the processing circuit 106 and then generates a binary status signal 110 at its output terminal (ie, link 111) in response to the detected electrical signal.

As illustrated in FIG. 1A, the rotatable shaft 108 can move linearly along its length and can rotate about its axis 112 (as illustrated in FIG. 1C). . As the rotatable shaft 108 moves linearly along its length, the processing circuit 106 maintains its binary voltage state signal at its output 111. In other words, the binary state output 111 of the processing circuit 106 does not change its binary state output in response to the linear movement of the rotatable shaft 108. The reason is that the detection device 104 cannot detect any changes in magnetic flux density and / or magnetic field from the linear movement of the rotatable shaft. However, when the rotatable shaft 108 rotates about its axis 112, the processing circuit 106 sets its binary voltage state between V _high and V _low at its output 111 based on the rotation angle of the rotatable shaft 108. It may be changed. In other words, the processing circuit 106 switches its binary state output 111 between V _high and V _low in response to the rotation angle of the rotatable shaft 108.

  FIG. 1B illustrates the position detection system 100 of FIG. 1 showing a top view of the rotatable shaft 108. In the top view of the rotatable shaft 108, the detection device 104 should be illustrated in a position above the magnet device 102 (a distance D (183) away). However, to better illustrate the principles of the present disclosure, in FIG. 2, the detection device 104 is the side of the rotatable shaft 108, but the upper and lower positional positions between the magnet device 102 and the detection device 104. Positioned illustratively using dotted lines 109 to reflect the relationship.

  As shown in FIG. 1B, whenever the rotatable shaft 108 moves linearly along its length, to ensure that the detection device 104 is within the effective detection area of the magnet device 102. The magnet device 102 has a length L along the longitudinal direction of the rotatable shaft 108. A dotted line 114 indicates a center line along the longitudinal direction of the rotatable shaft 108, and dotted lines 115 and 117 define a rotation range (−L 1, + L 1) of the rotatable shaft 108. In other words, when the rotatable shaft 108 rotates left and right around its axis 112, the center line 114 rotates in the directions of dotted lines 115 and 117, respectively.

  FIG. 1C illustrates the position detection system 100 of FIG. 1B showing a cross-sectional view of the rotatable shaft 108 along line AA in FIG. 1B.

  As illustrated in FIG. 1C, the rotatable shaft 108 moves from its center position (indicated by the centerline 113 in the diametrical direction of the rotatable shaft 108) to its left (indicated by the dotted line 121). It can rotate to the left until it reaches the rotation limit -Lm or it can rotate to the right until it reaches its right rotation limit + Lm (indicated by dotted line 123). Centerline 113 passes through centerline 114 and axis 112 of rotatable shaft 108 and disassembles. Thus, the two dotted lines 121 and 123 define an overall (or maximum) rotation range (−Lm, + Lm) for the rotatable shaft 108. Within the overall rotation range (−Lm, + Lm), the two dotted lines 115 and 117 define an internal rotation range (−L1, + L1) for the rotatable shaft. In the embodiment illustrated in FIG. 1C, the overall rotation range and the internal rotation range are symmetric with respect to the axis 112 and the centerline 113 on the rotatable shaft 108. That is, the rotation range between -Lm and -L1 is equal to the rotation range between + Lm and + L1 with respect to the axis 112 and the center line 113, respectively. However, an asymmetrical array of rotation ranges is possible for those skilled in the art. Furthermore, the entire rotation range (−Lm, + Lm) of the rotatable shaft 108 can be expanded to 360 degrees. To more clearly define the positional relationship between the components in FIGS. 1A-C, the diametrical centerline 113 of the rotatable shaft 108 is a straight line passing through the axis 112 and the length of the rotatable shaft 108. It should be noted that it is perpendicular to the centerline 114 along the direction.

By operating the detection device 104 and the processing circuit 106 together, the angular position of the rotatable shaft 108 can be detected and a binary state indication signal 107 on the output 111 can be generated. In particular, the processing circuit 106 has a high voltage state V _high (shown in FIG. 1C or a low voltage state V _low shown in FIG. 9B) when the rotatable shaft 108 is within the rotation range (−L1, + L1). ) A first signal state can be generated. The processing circuit 106 can operate when the rotatable shaft 108 is outside (or beyond) the rotational range (−L1, + L1) (low voltage state V _low illustrated in FIG. 1C or high illustrated in FIG. 9B). Generate a second signal state (of voltage state V _high ). Next, the binary state instruction signal 107 is applied to the ECU (engine control unit) 902 via the output terminal 111 of the processing circuit 106 (illustrated in FIG. 10).

  FIG. 2 illustrates an exemplary embodiment of the magnet device 102 and the detection device 104 illustrated in FIGS.

  As shown in FIG. 2, the magnet device 102 includes a magnet 204 having an S pole and an N pole. The south pole of the magnet 204 is fixed on the surface of the rotatable shaft 108. The front surface of the detection device 104 and the surface of the N pole of the magnet 204 are positioned facing each other. The S pole and N pole of the magnet 204 are aligned by the axis 112 and the radial center line 113 on the rotatable shaft 108. The detection device 104 is separated from the magnet 204 by a distance (or gap) D (183) and is flush with the magnet 204. As shown in FIG. 1B, the magnet 204 has a length L and a longitudinal centerline 114 along the longitudinal direction of the rotatable shaft 108. In order to more efficiently detect magnetic flux density changes from the magnet 204, in one embodiment, the sensitivity point of the detection device 104 is aligned by the longitudinal centerline 114 of the magnet 204.

As illustrated in FIG. 2, the detection device 104 includes a detection element 202 that can be a Hall effect detection device or a magnetoresistive (MR) detection device capable of generating an electrical signal when exposed to a rotating magnetic field. More particularly, the Hall effect detection element 202 includes a conductive semiconductor film for generating a low voltage that is perpendicular to the direction of current flow when subjected to a magnetic flux density change / magnetic field change that is normal to the film surface. can do. As illustrated in FIG. 2, the magnetic flux density and the magnetic field change in the gap 183 along the three dimensions 203 (B _x , B _y , B _z ). Detection device 104 is typically one of the B _x or B _y, or is designed to detect the magnetic field changes along both. The detection element 202 is configured on a detection position that is sensitive to and sensitive to changes in magnetic flux density / magnetic field generated by the rotating magnet 204. In Figure 2, B represents the magnetic flux density, B _x represents the magnetic flux density measurement is perpendicular to and detecting elements 202 along the radial direction of the shaft 108, B _y is tangent to the shaft 108 and detection A magnetic flux density measurement in the same plane with respect to the element 202 is shown.

  FIGS. 3A-C illustrate three embodiments of the detection system 100 illustrated in FIGS. 1A-C, according to the present invention.

  As shown in FIG. 3A, the detection device 104A has a front surface 305A and a back surface 306A, and the magnet device 102A includes a bipolar magnet 304A having an S pole and an N pole. The south pole of the magnet 304A is fixed to the surface of the rotatable shaft 108, and the front surface 305A of the detection device 104A and the north pole surface of the magnet 304A are positioned so as to face each other. The S pole and N pole of the magnet 304A are aligned by a radial center line 113 with respect to the rotatable shaft 108. The detection device 104A includes a detection element 302A, is separated from the magnet 304A by a distance (or gap) D (183), and is on the same plane as the magnet 304A. The bipolar magnet 304A and the detection position (where the detection element 302A is located) are in the same plane as the plane perpendicular to the axial direction of rotation of the bipolar magnet 304A. In order to concentrate / condense the magnetic flux density generated by magnet 304A, a pair of magnet concentrators 308A1 and 308A2 are located on two sides of bipolar magnet 304A and adjacent to bipolar magnet 304A.

  As shown in FIG. 3B, the detection device 104B has a front surface 305B and a back surface 306B, and the magnet device 102B includes a bipolar magnet 304B having an S pole and an N pole. The south pole of the magnet 304B is fixed to the surface of the rotatable shaft 108, and the front surface 305B of the detection device 104B and the north pole surface of the magnet 304B are positioned so as to face each other. The S pole and N pole of the magnet 304B are aligned by a radial center line 113 with respect to the rotatable shaft 108. The detection device 104B includes a detection element 302B, is separated from the magnet 304B by a distance (or gap) D (183), and is on the same plane as the magnet 304B. Similar to the structure shown in FIG. 3A, the bipolar magnet 304B and the detection position (where the detection element 302B is positioned) are in the same plane as the plane perpendicular to the axial direction of rotation of the bipolar magnet 304B. is there. In order to concentrate / condense the magnetic flux density generated by the magnet 304B, a magnetic flux density concentrator 309B is disposed on the back surface of the detection element 302B and adjacent to the detection element 302B.

  As shown in FIG. 3C, the detection device 104C has a front surface 305C and a back surface 306C, and the magnet device 102C includes a bipolar magnet 304C having an S pole and an N pole. The south pole of the magnet 304C is fixed to the surface of the rotatable shaft 108, and the front face 305C of the detection device 104C and the north pole surface of the magnet 304C are positioned so as to face each other. The S and N poles of magnet 304C are aligned by a centerline 113 with respect to rotatable shaft 108. The detection device 104C includes a detection element 302C, is separated from the magnet 304C by a distance (or gap) D (183), and is on the same plane as the magnet 304C. Similar to the structure shown in FIG. 3A, the bipolar magnet 304C and the detection position (where the detection element 302C is positioned) are in the same plane as the plane perpendicular to the axial direction of rotation of the bipolar magnet 304C. is there. A pair of magnet concentrators 308C1 and 308C2 are positioned on two sides of the bipolar magnet 304C and adjacent to the bipolar magnet 304C, respectively, to concentrate / condense the magnetic flux density generated by the magnet 304C. The magnetic flux density concentrator 309C is disposed on the back surface of the detection element 302C and adjacent to the detection element 302C.

  3B, 3C, 4B, and 4C, the distance between the detection element 302B (or 302C) and the concentrator 309B (or 309C) is 304B (or 304C). ) Must be the distance by which the magnetic field topology generated is adjusted. In one embodiment, the distance is selected to be 0.1 mm, although several variations are possible. For example, according to the magnetic field topology generated by 304B (or 304C), the distance between the detection element 302B (or 302C) and the concentrator 309B (or 309C) can be selected from 0.1 mm to 5 mm.

  3A, 3C, 4A, and 4C, the distance between the magnet 304A (or 404A or 404C) and the concentrators 308A1 and 308A2 (or 308C1 and 308C2). Is the distance by which the magnetic field topology generated by 304A and 304C (or 404A or 404C) is adjusted. In one embodiment, the distance is selected to be 0.1 mm, although several variations are possible. For example, according to the magnetic field topology generated by 304A and 304C (or 404A or 404C), the distance between the magnet 304A or 304C (or 404A or 404C) and the concentrator 308A1 and 308A2 (or 308C1 and 308C2) is 0. .Selectable from 1 mm to 10 mm.

  3 (A)-(C) and FIGS. 4 (A)-(C), distance (or gap) D (183) is a magnet that includes magnet size, magnet properties, radius of rotation, and expected performance. Determined / selected based on parameters 304A-304C and 404A-404C. In one embodiment of the present disclosure, the distance (or gap) D (183) is selected to be 2 mm, although several variations are possible. For example, the distance (or gap) D (183) is selected from 1 mm to 3 mm. The concentrators (308A1, 308A2, 308C1, 308C2, 309B and 309C) are formed from ferromagnetic materials or steels containing metal alloys with high concentrations of iron, non-exotic materials, and base metals.

  As shown in FIG. 1B, the magnets 304A-304C illustrated in FIGS. 3A-3C have a length L along the longitudinal direction of the rotatable shaft. In order to more efficiently detect a change in magnetic flux density from the magnets 304A to 304C, as an example, the sensitivity points of the detection elements 302A to 302C illustrated in FIG. 3C are the center lines of the magnets 304A to 304C. 114 is aligned. The detection elements 302A, 302B, or 302C can be Hall effect detection devices or magnetoresistive (MR) detection devices.

  4A-4C illustrate three additional embodiments of the position detection system 100 illustrated in FIGS. 1A-1C.

  4A-4C, the three additional embodiments each have almost the same structure as the embodiment in FIGS. 3A-3C, respectively, and FIG. ) To 4C, the magnetic polarization orientation of the magnets 402A to 402C is expected to be different from the magnetic polarization orientation of the magnets 302A to 302C shown in FIGS. 3A to 3C. Each of the N poles of magnets 404A-404C is secured onto the surface of rotatable shaft 108. The front surfaces 305A to 305C of the detection devices 104A to 104C and the surfaces of the south poles of the magnets 404A to 404C are positioned so as to face each other. The north and south poles of the magnets 404A-404C are aligned by the centerline 113 on the rotatable shaft 108.

FIG. 5A illustrates one embodiment of the processing circuit 106 in the position detection system 100 in more detail. As shown in FIG. 5A, the processing circuit 106 includes an A / D converter 502, a digital processing unit 504, and an indicating circuit 508, all of which are electrically connected together via links 503, 505 and 507. Connected to. When electrically connected to detection device 104 via link 109, A / D converter 502 receives an analog electrical signal as input from detection device 104 (ie, 104A-104C) and converts the analog electrical signal to digital electrical. The signal is processed and the digitized electrical signal is applied to the processing unit 504 via the link 503. Next, the processing unit 504 processes the digitized electrical signal to determine whether the rotatable shaft 108 is within the rotation range (−L1, + L1). Based on the determination, the processing unit 504 can output the binary state output 111 of the indicating circuit 508 (the high voltage state V _high or the high voltage state shown in FIG. The first signal state (low voltage state V _low ) shown in FIG. 9B is set. The processing unit 504 outputs the binary state output 111 of the indicating circuit 508 (the low voltage state V shown in FIG. 1C) when the rotatable shaft 108 is outside (or beyond) the rotational range (−L1, + L1). _low or the second signal state (in the high voltage state V _high shown in FIG. 9B).

More specifically, the binary state output 111 of the indication circuit 508 provides two control signals on the links 505 and 507, ie state control (having a first control signal state and a second control signal state) on the link 505. Based on the signal and the trigger signal (or trigger pulse) on the link 507, it can be set to either a high voltage state (V _high ) or a low voltage state (V _low ). When the digital processing unit 504 applies a trigger pulse on the link 507 and applies a state control signal on the link 505, the indicating circuit 508 is set to the same state control signal voltage state that is applied on the link 505. Is set. When the trigger signal is not applied on the link 507, the indication circuit 508 maintains its current output state regardless of the state control voltage state on the link 505. In one embodiment, the logic function of the instruction circuit 508 is implemented by using a JK register or a D register.

Thus, when the processing unit 504 determines that the rotatable shaft 108 is within the rotational range (−L1, + L1), it links the first control signal state (of high control state signal or low control state signal). Apply a trigger signal on link 507. Thereby, the instruction circuit 508 is set to the first signal state (in the high voltage state V _high illustrated in FIG. 1C or the low voltage state V _low illustrated in FIG. 9B). When the processing unit 504 determines that it is outside (or beyond) the rotational range (-L1, + L1), it links the second control signal state (of a low control state signal or a high control state signal) to the link 505. Apply a trigger signal on link 507. Thereby, the instruction circuit 508 is set to the second signal state (low voltage state V _low shown in FIG. 1C or high voltage state V _high shown in FIG. 9B).

  FIG. 5B illustrates another embodiment of the processing circuit 106 in the position detection system 100 in more detail. As illustrated in FIG. 5B, the processing circuit 106 ′ includes an analog processing unit 924 and a polarity circuit 928. Analog processing unit 924 has an input connected to link 109 and an output connected to polarity circuit 928 via link 925. The polarity circuit 928 has an output connected to the output terminal 111.

The analog processing unit 924 receives electrical signals from the detection device 104 (ie, 104A-104C) and processes them, and drives the first state when the rotatable shaft 108 is within the rotation range (−L1, + L1). A signal is generated, and a second state drive signal is generated when the rotatable shaft 108 is outside (or beyond) the rotation range (-L1, + L1). The polarity circuit 928 is responsive to the first state drive signal for a first state signal (of the high voltage state V _high illustrated in FIG. 1C or the low voltage state V _low illustrated in FIG. 9B). In response to the second state drive signal, the polarity circuit 928 is configured to change between the low voltage state V _low illustrated in FIG. 1C or the high voltage state V _high illustrated in FIG. 9B. 2 status signal.

More particularly, the threshold voltage is calibrated (or simulated) using the process associated with the description for FIG. The calibrated (or simulated) threshold voltage is then set in the analog processing unit 924. When the detected voltage from the detection device 104 is greater than or equal to the threshold voltage, the analog processing unit 924 generates a first state drive signal to cause the polarity circuit 928 (shown high in FIG. 1C). It is set to the voltage state V _high or the first state signal (of the low voltage state V _low illustrated in FIG. 9B). When the voltage detected from the detection device 104 (ie, 104A-104C) is less than the threshold voltage, the analog processing unit 924 generates a second state drive signal to cause the polarity circuit 928 (shown in FIG. 1C). Set to the low voltage state V _low or the second state signal (high voltage state V _high illustrated in FIG. 9B).

  The analog processing unit 924 is implemented using a low pass filter or some similar device.

  FIG. 6 illustrates the processing unit 504 illustrated in FIG. 5A in more detail. As shown in FIG. 6, the processing unit 504 includes a processor (or CPU) 602, a register 604, a memory device 606, an I / O circuit 608, and a bus 610. The processor 602, the register 604, the memory device 606, and the I / O circuit 608 are connected to the bus 610 via links 603, 605, 607, and 609, respectively. The memory device 606 includes a program (ie, a set of instructions), parameters (eg, reference voltages illustrated in FIGS. 7B and 8B), and digitized electrical signals. Data can be stored. The register 604 can store parameters and data. The I / O circuit 608 receives the input signal to the processing unit 504 and transmits the output signal from the processing unit 504 (for example, to the links 505 and 507). Register 604 may supply or hold signals based on content stored therein for one or more CPU operating cycles. As a result, the processor 602 can execute a plurality of operations within the CPU operation cycle.

  By executing a plurality of programs stored in the memory device 606, the processor (or CPU) 602 can control the operations of the plurality of registers 604, the memory device 606, and the I / O circuit 608. Read / write operations can be performed on register 604 and memory device 606. The I / O circuit 608 can receive an input signal from the A / D converter 502 and transmit an output signal from the processor (or CPU) 602 to the instruction circuit 508. To perform the comparison logic operation, the processor (or CPU) 602 can perform a comparison operation from two sources at inputs 613 and 615 to produce a comparison result for output 617. Includes a logical operation unit (not shown). The processor (or CPU) 602 can determine the subsequent operation based on the comparison result for the output 617. More specifically, based on the comparison results, the processor (or CPU) 602 can generate the desired state control signal and trigger signal (or trigger pulse) and send them to the links 505 and 507.

  FIG. 7A is related to the detection points of the detection element 202 along one dimension (X dimension or Y dimension) while the magnet 204 is rotating around the rotatable shaft 108 in FIG. A bell-shaped function curve 702 that reflects changes in magnetic flux density / magnetic field caused by the illustrated magnet 204 is illustrated. As shown in FIG. 7A, the bell-shaped function curve 702 is symmetric with respect to the vertical center line 703 corresponding to the radial center position of the rotatable shaft 108. As illustrated in FIG. 7A, the magnetic flux on the bell-shaped function curve 702 when the magnet 204 is in the position furthest away (corresponding to the line 703) with respect to the detection device 104 illustrated in FIG. The density is minimum. When the magnet 204 is rotating in the direction of the position closest to the detection device 104 (corresponding to the line 703), the magnetic flux density on the bell-shaped function curve 702 gradually increases to the maximum value. Next, when the magnet 204 is rotating in the direction of the position farthest away from the detecting device 104 (corresponding to the line 711) from the closest approach position, the magnetic flux density on the bell-shaped function curve 702 is minimized. Decrease.

  FIG. 7B shows a sensing element (302A or 302B) along one dimension (X or Y dimension) while the magnet (304A, 304B, 404A or 404B) is rotating about the rotatable shaft 108. ), The magnet (304A, 304B, 404A or 404B) as shown in FIG. 3 (A), FIG. 3 (B), FIG. 4 (A), or FIG. 4 (B). And a bell-shaped function curve 706 reflecting the flux density changes produced by one or more flux density concentrators (308A1, 308A2; 308C1, 308C2; 309B; or 309C). As shown in FIG. 7B, the bell-shaped function curve 706 is symmetric with respect to the vertical center line 707 corresponding to the radial center position of the rotatable shaft 108. As shown in FIG. 7B, the magnet (304A, 304B, 404A or 404B) is shown in FIGS. 3A, 3B, 4A, and 4B. When located at the position farthest from the detection device 104A or 104B (corresponding to the line 713), the magnetic flux density on the function curve 706 has a minimum value. When the magnet (304A, 304B, 404A or 404B) is rotating in the position direction closest to the detection device 104A or 104B (corresponding to the line 707), the magnetic flux density on the bell-shaped function curve 706 is the maximum value. Gradually increase to. On the bell-shaped function curve 706 when the magnet (304A, 304B, 404A or 404B) is rotating from the position closest to the detector 104A or 104B toward the position farthest away (corresponding to the line 711) The magnetic flux density decreases to a minimum value.

  In FIG. 7A, line 704 shows the magnetic flux density at a value of 70 percent (%) of the difference between the magnetic flux density maximum value and the magnetic flux density minimum value on the bell-shaped function curve 702. In FIG. 7B, line 708 indicates the magnetic flux density at a value of 70 percent (%) of the difference between the magnetic flux density maximum value and the magnetic flux density minimum value on the bell-shaped function curve 706.

  It should be noted that the bell-shaped function curve 706 in FIG. 7 (B) has a steeper slope than the bell-shaped function curve 702 in FIG. 7 (A). In order to better compare the performance of the two bell-shaped function curves illustrated in FIGS. 7A and 7B, the density output ratio G1 based on the bell-shaped function curve 702 is defined by the following equation.

  G1 is the ratio between H1 and W1 measured at a predetermined percentage (eg, 70%) of the magnetic flux density output on the bell-shaped function curve 702. Here, H1 represents a magnetic flux density value at a predetermined percentage on the bell-shaped function curve 702, and W1 represents a rotation angle range corresponding to the magnetic flux density value at a predetermined percentage on the bell-shaped function curve 702.

  Similarly, the density output ratio G2 based on the bell-shaped function curve 706 is defined by the following equation.

  G2 is the ratio between H2 and W2 measured at a predetermined percentage (eg, 70%) of the magnetic flux density output on the bell-shaped function curve 706. Here, H2 represents the magnetic flux density at a predetermined percentage on the bell-shaped function curve 706, and W2 represents the rotation angle range corresponding to the magnetic flux density value at the predetermined percentage on the bell-shaped function curve 706.

  Therefore, the density output ratio G2 for the bell-shaped function curve 706 is larger than the density output ratio G1 (G2> G1) for the bell-shaped function curve 702. The reason is that the function curve 706 has a steeper slope than the function curve 702.

  FIG. 8A shows the voltage output detected by the detection element 202 shown in FIG. 2 in response to the magnetic flux density change / magnetic field change related to the bell-shaped function curve 702 shown in FIG. A bell-shaped function curve 802 to be reflected is illustrated.

  FIG. 8B shows the response of the magnetic flux density change / magnetic field change related to the bell-shaped function curve 706 shown in FIG. 7B to FIG. 3A, FIG. 3B, FIG. ) Or a bell-shaped function curve 806 reflecting the voltage output detected by the detection element (302A or 302B) shown in FIG. 4B.

  Since the voltage is output, the bell-shaped function curve (voltage function curve) 802 illustrated in FIG. 8A is proportional to the bell-shaped function curve (magnetic flux density function curve) 702 illustrated in FIG. . Similarly, the bell-shaped function curve (voltage function curve) 808 illustrated in FIG. 8B is proportional to the bell-shaped function curve (magnetic flux density function curve) 708 illustrated in FIG.

  In order to better compare the performance of the two bell-shaped function curves illustrated in FIGS. 8A and 8B, the voltage output ratio G3 based on the function line 802 is defined by the following equation.

  G3 is the ratio between H3 and W3 measured at a predetermined percentage (eg, 70%) of the voltage output on the bell-shaped function curve 802. Here, H3 represents a voltage in a predetermined percentage on the bell-shaped function curve 802, and W3 represents a rotation angle range corresponding to the voltage value in the predetermined percentage on the bell-shaped function curve 802.

  Similarly, the voltage output ratio G4 based on the bell-shaped function curve 806 is defined by the following equation.

  G4 is the ratio between H4 and W4 measured at a predetermined percentage (eg, 70%) of the voltage output on the bell-shaped function curve 806. Here, H4 represents a voltage in a predetermined percentage on the bell-shaped function curve 806, and W4 represents a rotation angle range corresponding to the voltage value in the predetermined percentage on the bell-shaped function curve 806.

  Therefore, the voltage output ratio G4 with respect to the voltage function curve 806 is larger than the voltage output ratio G3 (G4> G3) with respect to the voltage function curve 802. This is because the voltage function curve 806 has a steeper slope than the voltage function curve 802.

  In FIG. 8A, line 804 shows the voltage at a value of 70 percent (%) of the difference between the maximum voltage value and the minimum voltage value on the function curve 802. In FIG. 8B, line 808 shows the voltage at a value of 70 percent (%) of the difference between the maximum voltage value and the minimum voltage value on the function curve 806.

  According to one embodiment, the voltage output curve 806 and the threshold line 808 are generated in a calibration (or simulation) process. In particular, when the magnet device 304A (or 304B) is continuously rotating around the axis 112 of the rotatable shaft 108, the detection device 104A (or 104B) is in one dimension (X or Y dimension). In response to the magnetic flux density change / magnetic field change generated by the magnet device 102A (or 102B) along, an electrical signal that fits the function curve 806 is generated.

  In performing a calibration (or simulation) process, a processing device (eg, processing circuit 106) processes an analog electrical signal that fits a function curve 806 (shown in FIG. 8B) to produce a line 808. A threshold voltage indicated by is generated. In particular, within processing circuit 106, A / D converter 502 receives analog electrical signals (conforming to function curve 806) from detection device 104A (or 104B), converts them into digital electrical signals, and digitizes them. The applied electrical signal is applied to the I / O circuit 608 in the processing unit 504. After receiving the digitized electrical signals, the processor (CPU) 602 in the processing unit 504 stores them in the memory device 606 and then uses the following mathematical equation (5) to express the digitized electrical signals: The signal is converted to a threshold voltage 808.

  In the present disclosure, the predetermined percentage value is selected as 70%, although other percentage values are possible.

FIG. 8C shows a binary state having a first signal state (high voltage V _high ) and a second signal state (low voltage V _low ) based on the bell-shaped function curve 806 in the calibration (or simulation) process. A method for forming the signal 107 is illustrated. Based on the mathematical formula (5), the digital processing circuit 106 shown in FIG. 5A (or the analog processing circuit 106 ′ shown in FIG. 5B) is used as the first binary state signal (high voltage V _high ). Threshold voltage 808 by matching all voltage points (or voltages) on bell-shaped function curve 806 equal to or greater than threshold voltage 808 and as a second binary state signal (low voltage Vlow) The binary state signal 107 is generated by matching all voltage points (or voltages) on the smaller bell-shaped function curve 806. When a calibration (or simulation) output is applied to the oscilloscope, the electrical signal illustrated in FIG. 8B is observed from the oscilloscope.

  In FIG. 8B, the width of the binary state signal 107 is set to deal with a variation in the operating conditions of the position detection system 100 (including variations in the gap and variations in temperature and parameters in the components). It is compensated by adjusting the value of the threshold voltage 808. According to one embodiment, the threshold voltage 808 generated in the calibration (or simulation) process is stored in the memory device 506. As a result, the processing circuit 504 can later use it to detect the rotational range of the rotatable shaft 108 in field use. According to another embodiment, the threshold voltage 808 generated in the calibration (or simulation) process is set in the analog processing unit 924. As a result, the analog processing unit 924 can be used to detect the rotational range of the rotatable shaft 108 in field use.

  It should be noted that the electronic non-contact detection device includes, but is not limited to, operations in manufacturing and / or operation, including variations in gaps used, variations in temperature and parameters in components. This means that you inevitably face a variation of the conditions. The adjustment / compensation capability is critical for measurement accuracy, especially for detecting a neutral position range relative to the gear shaft for the automobile. The basis for adjustment / compensation (including width and / or offset) is the use of a binary state signal to indicate the angular position range. In order to facilitate maintenance (maintenance management) of the position detection system 100, a calibration (or simulation) process is executed in field use by executing a calibration (or simulation) program stored in the processing circuit 106. . In one embodiment, the width of the binary state signal is adjusted by monitoring and updating the maximum and minimum peaks of the electrical signal that fit the bell-shaped function curve (806). Such an approach is a feasible and effective way to adjust the binary state signal.

  9A and 9B show that either the positive binary state signal 107 or the negative binary state signal 107 ′ indicates the rotation range (−L1, + L1) with respect to the rotatable shaft. Illustrate that it can be used.

In particular, as illustrated in FIG. 9A, when the rotatable shaft 108 is within the rotation range (−L1, + L1), the digital processing circuit 106 illustrated in FIG. _Is set to a high voltage state V _high indicated by When the rotatable shaft 108 is on the other side (or outside) of the rotation range (−L 1, + L 1), the processing unit 504 sets the instruction circuit 508 to the high voltage state V _high indicated by the line 919.

Alternatively, as illustrated in FIG. 9B, the binary state signal 107 ′ can be the inverse of the binary state signal 107. Accordingly, in FIG. 9B, when the rotatable shaft 108 is within the rotation range (−L1, + L1), the processing circuit 106 illustrated in FIG. 5A causes the indicating circuit 508 to be in a low voltage state indicated by line 917. Set to V _low . When the rotatable shaft 108 is on the other side (or outside) of the rotation range (−L 1, + L 1), the processing unit 504 sets the instruction circuit 508 to the high voltage state V _high indicated by the line 919.

  FIG. 10 illustrates an engine control system 900 in which the binary output 111 of the processing circuit 106 (or processing circuit 106 ') is used to control an engine in a vehicle. In FIG. 10, the engine control system 900 includes a detection device 104, a processing circuit 106, and an ECU (engine control unit) 902. In the engine control system 900, the rotatable shaft 108 is used as a gear shift lever, and the rotation range (−L1, + L1) reflects the neutral position range of the gear shift lever.

  As shown in FIG. 10, an ECU (Engine Control Unit) 902 receives a binary state signal on the link 111 as an input from the processing circuit 106 and an input 903 from a clutch detection circuit (not shown) of the automobile. Receive. Input 903 indicates whether the clutch of the automobile is being pressed. When the ECU 902 detects that the gearshift lever stays in a neutral position range based on a binary status signal on the link 111 for a specific time period (eg, 5 seconds, etc.), it Stop the engine. When the ECU 902 detects that the clutch of the vehicle is pressed based on the input on the link 903, the ECU 902 further determines whether the gear shift lever is within the neutral position range based on the binary state signal on the link 111. Detect if. When the gear shift lever is within the neutral position range, the ECU 902 starts only the engine. Therefore, the detection accuracy of the neutral position range with respect to the gear shift lever is important to ensure proper operation of the automobile.

  It should be noted that the bell-shaped function line 806 generates a binary state signal having a rotation angle arrangement that is narrower than the rotation angle arrangement of the rotatable shaft 108 with respect to the binary state signal generated by the bell-shaped line 802. Is that you can. It should be appreciated that a narrower binary state signal 107 is particularly desirable, particularly when the position detection system 100 is used to detect a neutral position range for a gear shift lever in an automobile.

  For field use, the digital processing circuit 106 illustrated in FIG. 5A or the analog processing circuit 106 ′ illustrated in FIG. 5B is responsive to the angle of rotation of the rotatable shaft 108 using the following steps, indicating circuit 508: Are set to the first signal state and the second signal state.

  For field use, according to one embodiment, when the rotatable shaft 108 is being rotated at a certain rotation angle, the detection device 104A (or 104B) can move the magnet device 102A or 102B along the X and / or Y dimensions. To generate an electrical signal in response to a change in magnetic flux density and / or a change in magnetic field. The detected voltage fits a bell-shaped curve 808 illustrated in FIG. The detection device 104 </ b> A (or 104 </ b> B) transmits an electrical signal to a processor (CPU) 602 in the processing circuit 106.

A processor (CPU) 602 compares the detected voltage with a threshold voltage 808. If the value of the detected voltage is equal to or greater than the threshold voltage 808, the processor (CPU) 602 generates a corresponding state control signal and trigger signal on links 505 and 507, respectively, to indicate the indication circuit 508. Set to the first signal state (high voltage state V _high illustrated in FIG. 1C or low voltage state V _low illustrated in FIG. 9B). If the detected voltage value is less than the threshold voltage 808, the processor (CPU) 602 generates a corresponding state control signal and trigger signal on the links 505 and 507, respectively, to indicate the indicating circuit 508 (FIG. Set to the second signal state (low voltage state V _low illustrated at 1C or high voltage state V _high illustrated in FIG. 9B).

  A program (or instruction set) for executing a specific step for setting the instruction circuit 508 is stored in the memory device 606 and executed by the processor (CPU) 602.

  For field use, according to another embodiment, the detection device 104A (or 104B) is one dimension (in the X and / or Y dimensions) when the rotatable shaft 108 is rotated at a rotation angle. In response to the magnetic flux density change and / or the magnetic field change caused by the magnet device 102A or 102B, an electrical signal is generated. The detected electrical signal fits a bell-shaped function curve 808 illustrated in FIG.

When the detected voltage of the electrical signal from the detector 104A (or 104B) is equal to or greater than the threshold voltage, the analog processing unit 924 generates a first state drive signal to cause the polarity circuit 928 (FIG. Set to a first state signal (high voltage state V _high illustrated at 1C or low voltage state V _low illustrated in FIG. 9B). When the detected voltage of the electrical signal from the detection device 104A (or 104B) is less than the threshold voltage, the analog processing unit 924 generates a second state drive signal to cause the polarity circuit 928 (in FIG. 1C). Set to the second state signal (in the illustrated low voltage state V _low or the high voltage state V _high illustrated in FIG. 9B).

  In order to reduce the cost of the ECU system, it is desirable to simplify the architecture of its control unit. One item of realizing it is to change the sensor input from the A / D converter input to the binary logic input in this control unit. This can be realized on the sensor side with a mechanical switch with the disadvantages of low measurement accuracy and poor reliability.

  It should be noted that the position detection system illustrated in FIG. 3 (C) or FIG. 4 (C) has two sets of magnetic density concentrators 308C1, 308C2, and 309C, so FIG. 3 (C) and FIG. The position detection system illustrated in C) has a steeper slope than the bell-shaped function curve generated by the detection system illustrated in FIGS. 3 (A) to 3 (B) and FIGS. 4 (A) to 4 (B). It is possible to generate a bell-shaped function curve having However, the implementation principle of generating a binary status signal for the position detection system illustrated in FIG. 3 (C) or FIG. 4 (C) is shown in FIGS. 3 (A)-(B) and 4 (A). It is the same as the implementation principle of generating a binary status signal for the position detection system illustrated in (B). Therefore, the position detection system illustrated in FIG. 3C or 4C is the same as the position detection system illustrated in FIGS. 3A to 3B and 4A to 4B. A binary state signal narrower than the binary state signal can be generated.

  It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the spirit and scope of the disclosure. Accordingly, the specification is intended to cover various modifications and variations of the embodiments described herein, and such modifications are within the scope of the appended utility model registration claims and their equivalents. And variations are provided.

Claims (24)

A magnetic device (102) for providing a magnetic field strength change / magnetic field change with respect to a detection position, the magnet device comprising:
Magnet members (304A-C, 404A-C) mounted on the rotatable shaft (108) and configured to rotate with the rotatable shaft (108);
A magnetic flux density concentrator (308A1, 308A2, 308C1, 308C2, 309B, 309C) for concentrating / condensing the magnetic field strength change / density of the magnetic field change,
The magnet device (102), wherein the magnet member generates the magnetic field intensity change / magnetic field change with respect to the detection position when the magnet member rotates around the rotatable shaft.   The magnet device according to claim 1, wherein the magnet device is used together with a detection device (104A-C) having the detection position where the detection element (302A-C) is positioned. The detection device includes the detection element having a front surface (301B to C) and a back surface (303B to C),
The magnet apparatus according to claim 1, wherein the magnetic flux density concentrator includes magnetic flux density concentrator elements (309B, 309C) positioned adjacent to the back surface (303B-C) of the detection element. The magnet member (304A, 304C, 404A, 404C) has a first side surface and a second side surface located on opposite sides of the magnet member,
The magnetic flux density concentrator further includes first and second magnetic flux density concentrator elements (308A1, 308A2, 308C1, 308C2),
The first magnetic flux density concentrator element is positioned adjacent to the first side of the magnet member;
4. The magnet apparatus according to claim 3, wherein the second magnetic flux density concentrator element is positioned adjacent to the second side surface of the magnet member. The magnet member (304A, 304C, 404A, 404C) has a first side surface and a second side surface located on opposite sides of the magnet member,
The magnetic flux density concentrator includes first and second magnetic flux density concentrator elements (308A1, 308A2, 308C1, 308C2),
The first magnetic flux density concentrator element is positioned adjacent to the first side of the magnet member;
The magnet device according to claim 1, wherein the second magnetic flux density concentrator element is positioned adjacent to the second side surface of the magnet member.   6. The magnet device according to claim 1, wherein the magnetic flux density concentrator increases an output ratio of the magnetic field strength change / magnetic field change of the magnet member.   6. The magnet device according to claim 1, wherein each of the magnetic flux density concentrator elements is made of a ferromagnetic material.   The magnet member is mounted such that the N pole and the S pole of the magnet member are arranged along the radial direction of the rotatable shaft. The magnet apparatus as described.   9. The magnet apparatus according to claim 8, wherein the magnet member and the detection position are in the same plane as a plane perpendicular to the axial direction of rotation of the magnet member.   10. The magnet apparatus according to claim 9, wherein the magnet member rotates around the rotatable shaft together with the first and second magnetic flux density concentrator elements (308A1, 308A2, 308C1, 308C2).   The magnet device according to claim 10, wherein a side surface center line of the first and second magnetic flux density concentrator elements is aligned with a side surface center line of the magnet member.   9. The magnet according to claim 8, wherein a center line of the magnetic flux density concentrator element (309B, 309C) and the detection position are aligned by the center line passing through the S pole and the N pole of the magnet member. apparatus. The magnet device is used together with the detection device (104A-C) having the detection position where the detection element (302A-C) is positioned,
The detection device has a front surface (305A to C) and a back surface (306A to C), and the front surface of the detection detection device faces the front surface of the detection device while the magnet member rotates the magnet member. Facing the north or south pole of the magnet member, the detector is separated from the magnet member by a distance,
2. The magnet device according to claim 1, wherein the south pole or the north pole is fixed on the rotatable shaft. A position detection system for generating a binary state signal for indicating an angular position range with respect to a rotatable shaft, the position detection system comprising:
The magnet device according to any one of claims 1 to 13, wherein the magnet device generates a magnetic field strength change / a magnetic field change,
A detection device (104A-C) for generating an electrical signal in response to the magnetic field strength change / magnetic field change;
A position detection system comprising: a processing circuit (106, 106 ') for generating the binary state signal in response to the electrical signal. The detection device has a front surface (305A-C) and a back surface (306A-C), and the front surface of the sensor circuit faces the front surface of the sensor circuit during rotation of the magnet member. Facing the north or south pole of the magnet member,
The position detection system according to claim 14, wherein the detection device is arranged separately from the magnet member.   16. A position detection system according to claim 15, wherein the sensor circuit is used to detect an angular position range of the rotatable shaft.   The position detection system according to claim 16, wherein the angular position range is a neutral position range with respect to the gear shift lever.   The position detection system according to claim 17, wherein the detection device includes a Hall effect sensor. The processing circuit includes a threshold circuit (604, 924) for providing a threshold voltage (808) on the bell-shaped function curve (806), and an indicating circuit (508, 928).
The indicating circuit generates a first signal state when the voltage of the detected electric signal is larger (or smaller) than the threshold voltage, and the voltage of the detected electric signal is the threshold value. 16. The position detection system according to claim 15, wherein the second signal state is generated when the voltage is smaller (or larger) than the voltage.   The threshold voltage and the bell-shaped function curve (806) are responsive to the flux density change / magnetic field change in one dimension when the bipolar magnet rotates 360 degrees around the rotatable shaft, 20. The position detection system according to claim 19, wherein the position detection system is calibrated before the position detection system is introduced.   21. The position detection system according to claim 20, wherein the binary state signal switches between the first signal state and the second signal state in response to an angular position change of the rotatable shaft. .   Monitor and update the maximum and minimum peaks of the electrical signal to adjust the binary state signal to compensate for deformations in gaps and operating conditions including temperature and parameter variations in the components used The position detection system according to claim 21, further comprising an adjustment circuit (504, 924) for performing the operation.   23. The position detection system of claim 22, wherein the binary status signal is adjusted by monitoring and updating maximum and minimum peaks of the electrical signal.   The position detection system according to claim 22, wherein the width of the binary state signal is adjusted by monitoring and updating the maximum and minimum peaks of the electrical signal.

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