JP2009121872A - Method and apparatus for detecting detection signals of magnetic sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To output detection signals from each magnetic sensor without being affected by overlapping from adjacent magnetic domains adjacent in the arrangement direction of magnetic sensors in the case of detecting a magnetized carrier through the use of a magnetic sensor array. <P>SOLUTION: A plurality of magnetic sensors 17 adjacently arranged in an array shape are actuated to the magnetized carrier in a direction which intersects at right angles with the traveling direction of the magnetized carrier 13 having a magnetized region 11. Output signals corresponding to directly opposite field strength from a directly opposite magnetic domain directly opposite to each magnetic sensor and adjacent field strength from an adjacent magnetic domain adjacent to the directly opposite magnetic domain are extracted from each magnetic sensor. Adjacent signal components caused by the adjacent field strength are corrected to each output signal to output directly opposite signal components caused by the directly opposite field strength as detection signals of each magnetic sensor. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and apparatus for operating a magnetic sensor in a magnetic carrier having a magnetized region and detecting a detection signal from the magnetic sensor.

  As is well known in the art, a magnetic sensor is used for a discriminating device that discriminates the authenticity of, for example, banknotes, checks, securities, etc. (see, for example, Patent Document 1). That is, by utilizing the fact that these bills, checks, securities, etc. are magnetic carriers having a magnetized region such as magnetic ink, a magnetic field intensity pattern from the magnetized region (hereinafter simply referred to as a pattern) is obtained using a magnetic sensor. Detected). Then, the magnetic carrier is discriminated by comparing the detected pattern of the magnetized region in the magnetic carrier with a reference pattern prepared in advance.

  In order to detect the pattern of the magnetization region of the magnetic carrier, a plurality of magnetic sensors are arranged adjacent to each other in an array in a direction perpendicular to the traveling direction of the magnetic carrier to be conveyed. The plurality of magnetic sensors, that is, the magnetic sensor array, outputs the magnetic field intensity from the magnetized region transported at a constant speed as a detection signal at regular time intervals. The entire pattern of the magnetized region is detected from the detection signal obtained at this time.

Here, when the magnetic sensor array is used to output the magnetic field intensity from the magnetized region as a detection signal, each magnetic sensor constituting the magnetic sensor array has a magnetic domain in the magnetized region facing each other, that is, from the directly facing magnetic domain. An output signal corresponding to the strength of the directly facing magnetic field is taken out and output as a detection signal.
JP 2006-236198 A

  However, when a magnetic medium is detected using a magnetic sensor array, each magnetic sensor has a magnetic field from a magnetic domain around each paired magnetic domain in addition to the corresponding magnetic field strength from the paired magnetic domain. A phenomenon called so-called overlap occurs that detects the intensity.

  Overlap occurs due to the spreading of the magnetic field from the magnetized region. That is, since the magnetic field from the magnetization region is detected by the magnetization sensor with a spread, the magnetic field from each magnetic domain is detected across not only the corresponding magnetization sensors but also the adjacent magnetic sensors. Therefore, as described above, each magnetic sensor detects not only the corresponding magnetic field strength but also the magnetic field strength from the magnetic domains around each corresponding magnetic field.

  Thus, when an overlap occurs when a magnetic medium is detected using a magnetic sensor array, the magnetic field strength from each magnetic domain is detected by a plurality of magnetic sensors. For this reason, each magnetic sensor detects and outputs an output signal corresponding to the strength of the corresponding magnetic field and the magnetic field strength due to overlap from the magnetic domains around each of the magnetic domains. As a result, there arises a problem that the resolution of each magnetic sensor is lowered and the reliability of the output detection signal is deteriorated.

  By the way, the overlap occurs particularly prominently in a magnetic sensor that is assumed to be used apart from a magnetic carrier to be detected, that is, a separated magnetic sensor. Compared with a so-called contact type magnetic sensor that is assumed to be used in close contact with a magnetic carrier to be detected, the separated type magnetic sensor has a large area of the opening that is opened to take in the magnetic field. Susceptible to magnetic fields due to surrounding magnetic domains.

  In addition, since the magnetic field expands in proportion to the distance from the magnetized region, the separation type magnetic sensor used with the separation distance between the magnetic sensor and the magnetic carrier set larger than that of the close contact type magnetic sensor is a direct It is easily affected by the magnetic field caused by the magnetic domains around the magnetic domain. Accordingly, when the magnetic carrier is detected using the separated magnetic sensor, the overlap significantly affects the output detection signal.

  Here, the overlap with each magnetic sensor is caused by the magnetic field strength from adjacent magnetic domains adjacent to each other in the magnetic sensor arrangement direction among the magnetic domains around each of the facing magnetic domains. Reduce the resolution.

  Of the magnetic domains around each pair of magnetic domains, the magnetic domain located in the traveling direction of the magnetic carrier to be conveyed is a magnetic domain that will eventually become the magnetic domain of each magnetic sensor and / or already Since the magnetic domains are the magnetic domains that are directly opposite to each magnetic sensor, the resolution of each magnetic sensor is not significantly reduced by the overlap from these magnetic domains.

  On the other hand, among the magnetic domains around each facing magnetic domain, the overlap from the adjacent magnetic domains adjacent in the magnetic sensor array direction affects each magnetic domain sensor constituting the magnetic sensor array. The resolution of the sensor is significantly reduced. Therefore, the overlap caused by the adjacent magnetic field strength affects the output detection signal.

  An object of the present invention is to detect each magnetization carrier using a magnetic sensor array by a contact type or a separation type magnetic sensor, without being affected by overlap from adjacent magnetic domains adjacent to each other in the arrangement direction of the magnetic sensor. The present invention proposes a detection method and a detection apparatus for a magnetic sensor detection signal for outputting a detection signal from the magnetic sensor.

  In order to achieve the above object, a magnetic sensor detection signal detection method according to the gist of the present invention includes the following steps.

  That is, a plurality of magnetic sensors arranged adjacent to each other in an array in the direction orthogonal to the traveling direction of the magnetic carrier having the magnetized region are operated with respect to the magnetic carrier.

  By this operation, each magnetic sensor outputs an output signal corresponding to the strength of the magnetic field directly opposite from the magnetic field directly opposite to the magnetic sensor and the magnetic field strength adjacent to the magnetic domain adjacent to this magnetic field. Take out.

  Then, the adjacent signal component due to the adjacent magnetic field strength is corrected for each output signal, and the directly facing signal component due to the directly facing magnetic field strength is output as the detection signal of each magnetic sensor.

  In addition, a magnetic sensor detection signal detection device according to the gist of the present invention has the following features in order to perform the above-described magnetic sensor detection signal detection method.

  That is, a detection device for a magnetic sensor detection signal operates on a magnetic carrier having a magnetized region, and a plurality of magnetic sensors arranged adjacent to each other in an array in a direction perpendicular to the traveling direction of the magnetic carrier; Correction means for correcting the output signals of these magnetic sensors and outputting detection signals is provided.

  The plurality of magnetic sensors correspond to the magnetic field strengths from the magnetic domains directly facing the magnetic sensors and the magnetic field strengths from the magnetic domains adjacent to the magnetic domains. The output signal is taken out.

  Further, the correction means corrects the adjacent signal component caused by the adjacent magnetic field strength with respect to each output signal, and outputs the facing signal component caused by the facing magnetic field strength as the detection signal.

  According to the detection method and the detection apparatus of the magnetic sensor detection signal according to the gist of the present invention, the output signal extracted by each magnetic sensor by the correcting unit is over the adjacent signal component caused by the adjacent magnetic field strength, that is, the overshoot from the adjacent magnetic domain. The signal component extracted by the wrap is corrected. As a result, the directly-facing signal component caused by the directly-facing magnetic domain is output as the detection signal of each magnetic sensor.

  Therefore, the magnetic sensor detection signal detection method and detection apparatus according to the gist of the present invention can output the detection signal without including the adjacent signal component due to the overlap from the adjacent magnetic domain. Therefore, the magnetic sensor detection signal detection method and detection apparatus according to the gist of the present invention can suppress a decrease in resolution of the magnetic sensor due to the overlap even when the separation type magnetic sensor is used.

  Hereinafter, an exposure position determination method according to an embodiment of the present invention will be described with reference to the drawings. Each figure only schematically shows the shape, size, and arrangement relationship of each component to the extent that the present invention can be understood. Therefore, the configuration of the present invention is not limited to the illustrated configuration example.

<Embodiment>
In this embodiment, a magnetic sensor detection signal detection method for detecting a magnetic carrier using a magnetic sensor array, without being affected by overlap from adjacent magnetic domains adjacent to each other in the magnetic sensor arrangement direction, A method for detecting a magnetic sensor detection signal for outputting a detection signal from the magnetic sensor and a detection apparatus for the magnetic sensor detection signal will be described.

  FIG. 1 is a perspective view for explaining a magnetic sensor detection signal detection method and a detection apparatus according to this embodiment of the present invention.

  FIG. 2 is a plan view for explaining this embodiment of the magnetic sensor detection signal detection method and detection apparatus of the present invention.

  FIG. 3 is a diagram for explaining the embodiment of the detection method and the detection apparatus of the magnetic sensor detection signal according to the present invention, as seen from the direction of the arrow at the cut line in the II line shown in FIG. It is an end view.

  The detection method and detection device for a magnetic sensor detection signal according to this embodiment detect a magnetization carrier 13 having a magnetization region 11 that travels along a certain reference plane. Therefore, in this embodiment, this reference plane is set as a running plane 15 in which the magnetization carrier 11 is installed and runs in the horizontal direction (see FIG. 3). The traveling direction of the magnetic carrier 13 is indicated by an arrow in each figure.

  In addition, the magnetic carrier 13 detected by the detection method and detection device of the magnetic sensor detection signal according to this embodiment is, for example, a paper sheet having a magnetic region such as a banknote, a check, or a securities, or other magnetic region. It is the flat structure which has. And the magnetization carrier 13 has the magnetization area | region 11 in the whole surface or one part of the detection surface 13a. In the configuration example of FIGS. 1 and 2, the magnetization carrier 13 having the magnetization region 11 in a part of the detection surface 13a is shown.

  The magnetic sensor detection signal detection device according to this embodiment includes a magnetic sensor 17 and a correction means 19.

  The magnetic sensor 17 is provided for the purpose of detecting the magnetic carrier 13. For this purpose, a plurality of magnetic sensors 17 are arranged adjacent to each other in an array in the direction orthogonal to the traveling direction of the magnetic carrier 13, that is, in the arrangement direction indicated by the arrows in FIGS. Hereinafter, the plurality of magnetic sensors 17 arranged in an array are also referred to as a magnetic sensor array 21. Hereinafter, the arrangement direction of the magnetic sensors 17 is also simply referred to as the direction of the magnetic sensors 17.

  The number of magnetic sensors 17 to be arranged is set according to the width of the magnetic carrier 13 to be detected in the direction of the magnetic sensor 17. That is, in order to detect the magnetic carrier 13 using the magnetic sensor array 21, the magnetic carrier 13 is arranged so that the width in the arrangement direction of the magnetic sensor array 21 is larger than the width in the direction of the magnetic sensor 17. The number of magnetic sensors 17 to be set is set. In this embodiment, the number of magnetic sensors 17 is set so that at least the first magnetic sensor from both ends of the plurality of magnetic sensors 17 constituting the magnetic sensor array 21 does not face the magnetic carrier 13. . Therefore, the magnetic sensor array 21 includes a magnetic sensor 17 facing the magnetic carrier 13 (hereinafter also referred to as a counter magnetic sensor 18a) and a magnetic sensor 17 not facing the magnetic carrier 13 (hereinafter also referred to as a non-opposing magnetic sensor 18b). Including. And the non-opposing magnetic sensor 18b is arrange | positioned on both sides of the opposing magnetic sensor 18a. 1 and 2, eight magnetic sensors 17, that is, a magnetic sensor 17a, a magnetic sensor 17b, a magnetic sensor 17c, a magnetic sensor 17d, a magnetic sensor 17e, a magnetic sensor 17f, a magnetic sensor 17g, and a magnetic sensor 17h are illustrated. An example of the arrangement is shown. 1 and FIG. 2, among the eight magnetic sensors 17, the magnetic sensor 17c, the magnetic sensor 17d, the magnetic sensor 17e, and the magnetic sensor 17f are opposed to the magnetic carrier 13 that is the detection target. This is a counter magnetic sensor 18a. The magnetic sensor 17a, the magnetic sensor 17b, the magnetic sensor 17g, and the magnetic sensor 17h are non-opposing magnetic sensors 18b that are not opposed to the magnetic carrier 13.

  The magnetic sensor array 21 operates at regular intervals in order to detect the magnetic carrier 13 traveling on the traveling surface 15 at a constant speed. Then, by each operation, an output signal corresponding to the detected magnetic field strength is taken out from each magnetic sensor 17. In this embodiment, each magnetic sensor 17 operates simultaneously with respect to the magnetic carrier 13 by sending an operation signal from the drive circuit 22 to each magnetic sensor 17 at regular intervals.

  The traveling speed of the magnetic carrier 13 and the time intervals between the operations are preferably set arbitrarily and appropriately according to the type of the magnetic carrier to be detected, the accuracy of the detection signal to be obtained, and the like. Further, the magnetic carrier 13 travels on the traveling surface 15 by being conveyed by, for example, a known roller (not shown).

  Each magnetic sensor 17 is adjacent to each magnetic domain 23 in the magnetic carrier 13 facing directly to each of the magnetic sensors 17, that is, the strength of the facing magnetic field from the facing magnetic domain, and adjacent to each facing magnetic domain in the arrangement direction of the magnetic sensor 17. An output signal corresponding to the adjacent magnetic field intensity from the adjacent magnetic domain is extracted. Here, in the configuration example of FIG. 1, the magnetic sensor 17c faces the magnetic domain 23c, the magnetic sensor 17d faces the magnetic domain 23d, the magnetic sensor 17e faces the magnetic domain 23e, and the magnetic sensor 17f faces the magnetic domain 23f. Therefore, each of these combinations indicates the relationship between each magnetic sensor 17 and the corresponding directly-facing magnetic domain. In addition, the magnetic domains adjacent to each facing magnetic domain in the arrangement direction of the magnetic sensors are adjacent magnetic domains corresponding to the magnetic sensors 17. For example, the adjacent magnetic domains corresponding to the magnetic sensor 17d are the magnetic domains 23c and 23e adjacent to the magnetic domain 23d that is the directly-facing magnetic domain of the magnetic sensor 17d.

  In the magnetic sensor detection signal detection method according to the present embodiment, the magnetic sensor array 21 arranged in this manner causes each magnetic sensor 17 to have a magnetic field strength from the magnetic field directly opposite to each other. An output signal corresponding to the adjacent magnetic field intensity from the adjacent magnetic domain adjacent to each directly facing magnetic domain is extracted.

  In addition, the magnetic sensor array 21 is connected to the correction unit 19 via the amplifier circuit 25 and the A / D converter 29. The amplification circuit 25 amplifies the information of the output signal taken out by each magnetic sensor 17 constituting the magnetic sensor array 21 at the same magnification. The A / D converter 29 converts the information of the amplified output signal into digital data and inputs the digital data.

  And in the detection method of the magnetic sensor detection signal which concerns on this embodiment, each output signal obtained by the magnetic sensor array 21 detecting the magnetic carrier 13 is sent through the circuit unit 25 and the A / D converter 29. An input is made to the correction means 19 for each magnetic sensor 17.

  The correcting means 19 is installed for the purpose of correcting the adjacent signal component caused by the adjacent magnetic field strength with respect to the output signal and outputting the facing signal component caused by the facing magnetic domain as a detection signal.

  As already described, each magnetic sensor 17 detects the strength of the opposite magnetic field and the strength of the adjacent magnetic field. Therefore, the output signal taken out by each magnetic sensor 17 includes a directly-facing signal component and an adjacent signal component resulting from the directly-facing magnetic field strength and the adjacent magnetic field strength.

  Here, the adjacent signal component included in the output signal is a signal component caused by an undesired adjacent magnetic field strength detected by the above-described overlap. And as already demonstrated, due to the detection of the adjacent magnetic field strength due to the overlap, there is a risk that the resolution of each magnetic sensor 17 is lowered or the reliability of the detection signal to be output is deteriorated.

  Therefore, in the detection method of the magnetic sensor detection signal according to this embodiment, the adjacent signal component is corrected by the correction means 19 such as a well-known computer (CPU) installed in the detection device, and only the direct signal component is detected. Is output as a detection signal of each magnetic sensor 17.

  For this purpose, the correction unit 19 includes a control unit 32, a storage unit 33, a processing unit 35, and a determination unit 36.

  Incidentally, as already described, in the magnetic sensor detection signal detection method and detection apparatus according to this embodiment, the magnetic sensor array 21 includes the opposing magnetic sensor 18a and the non-opposing magnetic sensor 18b, and the non-facing magnetic sensor 18b. Are arranged with the opposing magnetic sensor 18a interposed therebetween. That is, in this embodiment, the n magnetic sensors arranged in order from the first to the n-th (n is a natural number excluding 0) facing the magnetic carrier 13 are arranged on the plurality of magnetic sensors 17 in order. It is included as 18a. In FIG. 1 and FIG. 2, four counter magnetic sensors 18a are included, and in order, the magnetic sensor 17c is the first counter magnetic sensor 18a, the magnetic sensor 17d is the second counter magnetic sensor 18a, and the magnetic sensor 17e. A configuration example is shown in which the third counter magnetic sensor 18a and the magnetic sensor 17f are replaced with a fourth counter magnetic sensor 18a.

  Here, each opposing magnetic sensor 18a has an adjacent signal calculated by the product of the magnetic field intensity from the adjacent magnetic domain and the correction coefficient α (α is a real number of 0 <α <1) in addition to the corresponding direct signal component. Take out the ingredients. Α is a specific constant corresponding to the sensitivity of the magnetic sensor 17 and the separation distance between the magnetic sensor 17 and the magnetic medium 13, and is actually calculated using a reference magnetic carrier having a known magnetic field strength. Possible value. In this embodiment, α is calculated in advance.

  Among the first to nth counter magnetic sensors 18a, the counter magnetic sensors located at both ends, that is, the first counter magnetic sensor (hereinafter also referred to as the first magnetic sensor), and the nth The i-th (i is a natural number of 1 <i <n) -th counter magnetic sensor (hereinafter also referred to as the i-th magnetic sensor) excluding the counter magnetic sensor (hereinafter also referred to as the n-th magnetic sensor) In addition to the positive signal component from the direct magnetic domain, adjacent signal components on both sides of the i-th positive magnetic domain, that is, the adjacent signal components from the (i-1) th adjacent magnetic domain and the (i + 1) th adjacent magnetic domain are detected.

Here, A _i is an output signal taken out by the i-th magnetic sensor, and B _i is a direct signal component caused by the i-th direct magnetic domain. Further, when B _i-1 is a signal component resulting from the i−1 adjacent magnetic domain and B _{i + 1} is a signal component from the i + 1 adjacent magnetic domain, the adjacent signal component taken out by the i th magnetic sensor is αB _i−1 + αB. _{i + 1} . Therefore, the output signal A _i taken out by the i-th magnetic sensor is expressed by the following equation (1).

A _i = B _i + αB _i−1 + αB _{i + 1} (1 <i <n) (1)
In addition, among the first to nth counter magnetic sensors 18a, counter magnetic sensors located at both ends, that is, a first magnetic domain and an n-th counter-facing facing the first magnetic sensor and the n-th magnetic sensor, respectively. The magnetic domains are located at both ends of each magnetic domain 23 in the arrangement direction of the magnetic sensor 17. Accordingly, each of the first and n-th pair magnetic domains is adjacent to one adjacent magnetic domain on one side in the arrangement direction of the magnetic sensor 17.

  Therefore, the first magnetic sensor detects the adjacent signal component from the first adjacent magnetic domain, that is, the adjacent signal component from the second adjacent magnetic domain, in addition to the positive signal component from the first directly opposed magnetic domain. The n-th magnetic sensor has an adjacent signal component from the n-1 adjacent magnetic domain, that is, an adjacent signal component from the n-1 adjacent magnetic domain, in addition to the positive signal component from the n-th positive magnetic domain. Is detected.

Here, the output signal taking out the A ₁ is the first magnetic sensor, confronting signal component due to B ₁ in the first confronting magnetic domain, the output signal taking out the A _n is the n-th magnetic sensor, and B _n n-th positive The signal component is a directly-facing signal component due to the magnetic domain. Further, when B ₂ is a signal component caused by the second adjacent magnetic domain and B _n-1 is a signal component caused by the n-1 adjacent magnetic domain, the adjacent signal component taken out by the first magnetic sensor is αB ₂ , The adjacent signal component taken out by the n-th magnetic sensor is αB _n−1 . Therefore, the output signal A ₁ in which the first magnetic sensor taken is represented by the following equation (2). The output signal A _n the n-th magnetic sensor taken is represented by the following equation (3).

A ₁ = B ₁ + αB ₂ (i = 1) (2)
A _n = B _n + αB _n-1 (i = n) (3)
Here, as a matter of course, the (i-1) -th adjacent magnetic domain is the (i-1) -th facing magnetic domain facing the (i-1) -th i-1th magnetic sensor in the opposed magnetic sensor 18a. Therefore, B _i−1 is a directly-facing signal component corresponding to the i−1th magnetic sensor. Further, the (i + 1) -th adjacent magnetic domain is the (i + 1) -th facing magnetic domain that faces the (i + 1) -th i + 1-th magnetic sensor in the opposed magnetic sensor 18a. Therefore, B _{i + 1} is a directly-facing signal component corresponding to the i + 1 th magnetic sensor. The second adjacent magnetic domain is a second directly-facing magnetic domain that faces the second second magnetic sensor in the opposed magnetic sensor 18a. Accordingly, B ₂ is a confronting signal component corresponding to the second magnetic sensor. The (n−1) -th adjacent magnetic domain is the n−1 directly opposed magnetic domain that faces the (n−1) th n−1 magnetic sensor among the opposed magnetic sensors 18a. Therefore, B _n−1 is a directly-facing signal component corresponding to the n−1 th magnetic sensor.

  Further, the non-opposing magnetic sensor 18b in the magnetic sensor array 21 does not need to detect a detection signal because there is no facing magnetic domain. Therefore, the non-opposing magnetic sensor 18b regards the output signal as 0.

In the above-described formulas (1) to (3), A ₁ , A _i , and _An are actual measured values of output signals extracted by detecting the magnetic carrier 13 by the magnetic sensor array 21. As already described, α is a correction coefficient calculated and set in advance. Accordingly, by inputting the output signal taken out from each counter magnetic sensor 18a into the formulas (1) to (3), the number of terms of the opposite signal component of each counter magnetic sensor 18a to be detected and the number of formulas Can be matched. Therefore, by using the equations (1) to (3), the directly-facing signal component of each counter magnetic sensor 18a can be calculated.

  Hereinafter, an example in which the detection device according to this embodiment includes the configuration of FIGS. 1 and 2, that is, the four opposing magnetic sensors 18 a of the sensor magnetic sensor 17 c, the magnetic sensor 17 d, the magnetic sensor 17 e, and the magnetic sensor 17 f. In the following, a method for calculating the directly-facing signal component of each opposing magnetic sensor 18a using equations (1) to (3) will be described.

  1 and 2, the magnetic sensor array 21 includes, as first to fourth opposing magnetic sensors 18a, a magnetic sensor 17c (hereinafter also referred to as a first magnetic sensor 17c) and a magnetic sensor 17d (hereinafter referred to as a first magnetic sensor 17c). , A second magnetic sensor 17d), a magnetic sensor 17e (hereinafter also referred to as a third magnetic sensor 17e), and a magnetic sensor 17f (hereinafter also referred to as a fourth magnetic sensor 17f). That is, in this configuration example, n = 4.

Since the first magnetic sensor 17c is the first of the opposing magnetic sensors 18a and is located at one end in the arrangement direction of the magnetic sensors 17, it calculates the directly-facing signal component using the above equation (2). To do. That output signal _{A 1} in which the first magnetic sensor 17c is taken out is directly opposite the positive-to-signal components _{B 1} from the magnetic domains 23c, to include the adjacent signal component alpha B ₂ from the magnetic domains 23d is adjacent magnetic domains of the magnetic domain 23c, the above-mentioned It is represented by the following formula (4) using formula (2).

A ₁ = B ₁ + αB ₂ (4)
The second magnetic sensor 17d is an i-th magnetic sensor located between the first magnetic sensor 17c and the n-th magnetic sensor, that is, the fourth magnetic sensor 17f in this configuration example. Therefore, the directly facing signal component is calculated using the above-described equation (1). That is, the output signal _{A 2} of the second magnetic sensor 17d taken is directly opposite the positive-to-signal components _{B 2} from the magnetic domains 23d, the magnetic domain 23c and the adjacent signal components alpha B ₁ and alpha B ₃ from the magnetic domains 23e is adjacent magnetic domains of the magnetic domain 23d Therefore, it is expressed by the following formula (5) using the above formula (1).

A ₂ = B ₂ + αB ₁ + αB ₃ (5)
The third magnetic sensor 17e is an i-th magnetic sensor located between the first magnetic sensor 17c and the n-th magnetic sensor, that is, the fourth magnetic sensor 17f in this configuration example. Therefore, the directly facing signal component is calculated using the above-described equation (1). That is, the output signal _{A 3} to the third magnetic sensor 17e is taken out, the positive-to-signal component _{B 3} from directly facing magnetic domains 23e, domains 23d and the adjacent signal components alpha B ₂ and alpha B ₄ from the magnetic domains 23f is adjacent magnetic domains of the magnetic domain 23e Therefore, it is expressed by the following formula (6) using the above formula (1).

A ₃ = B ₃ + αB ₂ + αB ₄ (6)
The fourth magnetic sensor 17f is the n-th of the opposing magnetic sensors 18a and is located at one end opposite to the first magnetic sensor 17c in the arrangement direction of the magnetic sensors 17, and thus the above-described formula ( 3) is used to calculate the facing signal component. That is, the output signal _{A 4} which is fourth magnetic sensor 17f taken is directly opposite the positive-to-signal component _{B 4} from the magnetic domains 23f, to include the adjacent signal component alpha B ₃ from the magnetic domains 23e is adjacent magnetic domains of the magnetic domain 23f, above It is represented by the following formula (7) using formula (3).

A ₄ = B ₄ + αB ₃ (7)
From these formulas (4) to (7), B ₂ and B ₃ are represented by the following formulas (8) and (9).

_{B 2 = {(A 2 -αA} 1) (1-α 2) -αA 3 + α 2 A 4} / (1-3α 2 + α 4) ··· (8)
B ₃ = (A ₃ -αA ₄ -αB ₂ ) / (1-α ² ) (9)
B ₂ and B ₃ are calculated by substituting A ₁ , A ₂ , A ₃ , A ₄ and the correction coefficient α taken out by the opposing magnetic sensors 18a into these equations (8) and (9). Can do. Then, B ₁ and B ₄ can be calculated by substituting the calculated B ₂ and B ₃ into the equations (4) and (7).

  In the method of detecting a magnetic sensor detection signal according to this embodiment, the expressions (1) to (3) are stored in advance in the storage unit 33 of the detection device in order to correct the output signal extracted by each magnetic sensor 17. .

Then, in the processing unit 35, the respective output signals A _i (i is 1 ≦ i) extracted by the n magnetic sensors 17, that is, the counter magnetic sensors 18 a from the formulas (1) to (3) read from the storage unit 33. Each of the directly facing signals B _i (i is a natural number of 1 ≦ i ≦ n) is calculated using a value of ≦ n natural number).

More specifically, the control unit 32 identifies each output signal A _i extracted by each magnetic sensor 17. Then, each output signal for each identified magnetic sensor 17 is input to the storage unit 33.

Based on the identified output signals, the processing unit 35 outputs the output signals from the n magnetic sensors 17, that is, the counter magnetic sensors 18 a, according to the positions of the counter magnetic sensors 18 a, Formula (1), Formula (2) ) Or equation (3), and the directly-facing signal component B _i is calculated.

  Further, the processing unit 35 regards an output signal from the magnetic sensor 17 arranged at a position not facing the magnetic carrier 13, that is, the non-opposing magnetic sensor 18 b as 0.

Then, the detection device, for example a known printer, using a display or the like, and outputs a confronting signal components B _i as a detection signal.

  Thus, in the detection method of the magnetic sensor detection signal according to this embodiment, only the directly-facing signal component can be output as the detection signal by the correction means 19 installed in the detection device.

  Further, the magnetic sensor detection signal detection device according to this embodiment includes an optical sensor 37. In the detection method of the magnetic sensor detection signal according to this embodiment, the n magnetic sensors 17 facing the magnetic carrier 13 are selected from the magnetic sensor array 21 using the optical sensor 37.

  As already described, in the magnetic sensor detection signal detection method according to this embodiment, the correction means 19 uses the output signals extracted from the opposing magnetic sensor 18a as the expressions (1) and (1) corresponding to the respective positions. Input to (2) or equation (3). Therefore, in this embodiment, the processing unit 35 is made to discriminate the output signal from each magnetic sensor 17 from the output signal from the opposing magnetic sensor 18a and the output signal from the non-opposing sensor 18b. Then, the processing unit 35 recognizes the positions of the magnetic sensors 17 located at both ends in the arrangement direction of the magnetic sensors 17 among the opposed magnetic sensors 18 a included in the magnetic sensor array 21, that is, the positions of the first magnetic sensor and the n-th magnetic sensor. Let

  Therefore, in this embodiment, before the magnetic carrier 13 traveling on the traveling surface 15 is detected by the magnetic sensor array 21, an optical signal is obtained from the magnetic carrier 13 using the optical sensor 37, thereby obtaining the magnetic carrier. 13, the width W of the magnetic sensor 17 in the arrangement direction is detected.

  The optical sensor 37 is connected to the correction means 19 via the amplifier circuit 39 and the A / D converter 41. The amplifier circuit 39 amplifies the optical signal acquired by the optical sensor 37 at the same magnification. The A / D converter 41 is installed for the purpose of converting the amplified optical signal into digital data and inputting it into the correction means 19.

  In this embodiment, the width W of the magnetic carrier 13 detected by the optical sensor 37 is input to the determination unit 36 of the correction means 19. As a result, when the traveling magnetic carrier 13 is detected by the magnetic sensor array 21, the determination unit 36 sets each magnetic sensor 17 to the opposing magnetic sensor 18 a that faces the magnetic carrier 13 and the magnetic carrier 13 that does not face the magnetic carrier 13. It discriminate | determines from the opposing magnetic sensor 18b. Based on the information from the determination unit 36, the processing unit 35 selects n magnetic sensors corresponding to the detected width W from the plurality of magnetic sensors 17. As a result, in this embodiment, the processing unit 35 inputs the extracted output signals into the formula (1), the formula (2), or the formula (3) corresponding to the position of the respective opposing magnetic sensor 18a. be able to.

  Here, in this embodiment, when the magnetic sensor array 21 includes the magnetic sensor 17 partially facing the magnetic carrier 13, the magnetic sensor 17 is recognized by the determination unit 36 as the opposing magnetic sensor 18 a. The

  When the width W of the magnetic carrier 13 in the arrangement direction of the magnetic sensors 17 is not constant, the determination unit 36 determines the magnetic field based on the traveling speed of the magnetic carrier 13 and the time interval between each operation of the magnetic sensor array 21. For each operation of the sensor array 21, the processing unit 35 selects n magnetic sensors corresponding to the width W of the magnetic carrier 13 during the operation.

  As the optical sensor 37, for example, a transmissive optical sensor, a reflective optical sensor, or any other known optical sensor is used according to the design. In the configuration example of FIGS. 1 and 2, the light source 37a for irradiating the magnetic carrier 13 and the light receiving surface 37ba are opposed to the running surface 15 in order to acquire the transmitted light from the irradiated magnetic carrier 13. This shows a case where a transmission type optical sensor having a light receiving portion 37b arranged in the manner described above is used.

  In this embodiment, an operation signal is sent from the drive circuit to the optical sensor 37 at regular intervals, so that the optical sensor 37 operates simultaneously with respect to the magnetic carrier 13. As the drive circuit for operating the optical sensor 37, the drive circuit 22 for operating the magnetic sensor 17 described above is preferably used in common. In each drawing, a configuration example in which the magnetic sensor 17 and the optical sensor 37 are operated by a common drive circuit 22 is shown. In this embodiment, the drive circuit may be controlled by the control unit 32 (not shown).

  In this embodiment, in order to accurately detect the width W of the magnetic carrier 13, it is preferable to set the resolution of the optical sensor 37 included in the detection device to at least twice the resolution of the magnetic sensor 17. . That is, preferably, in the magnetic sensor detection signal detection device according to this embodiment, the number of photosensors 37 at least twice that of the magnetic sensors 17 constituting the magnetic sensor array 21 is arranged. The optical sensors 37 are preferably arranged adjacent to each other in parallel with the arrangement direction of the magnetic sensor array 21. In the configuration example of FIGS. 1 and 2, the number of the light receiving portions 37 b of the transmissive optical sensor 37 is the number of the magnetic sensors 17, that is, the resolution of the optical sensor 37 is set to be twice that of the magnetic sensor 17. Show. Further, a plurality of light sources 37a may be arranged corresponding to the light receiving unit 37b (not shown).

  According to the detection method and the detection apparatus of the magnetic sensor detection signal according to this embodiment, the correction means 19 is adjacent to the output signal taken out by each magnetic sensor 17 facing the magnetic carrier 13, that is, each opposing magnetic sensor 18a. The adjacent signal component caused by the magnetic field strength, that is, the signal component extracted by the overlap from the adjacent magnetic domain is corrected. As a result, the directly-facing signal component caused by the directly-facing magnetic domain is output as the detection signal of each counter magnetic sensor 18a.

  Therefore, the magnetic sensor detection signal detection method and detection apparatus according to this embodiment can output a detection signal without including adjacent signal components due to overlap from adjacent magnetic domains. Therefore, in the detection method and detection apparatus of the magnetic sensor detection signal according to this embodiment, it is possible to suppress a decrease in the resolution of each magnetic sensor 17 due to the overlap even when the separation type magnetic sensor is used.

It is a perspective view with which it uses for description of the detection method and detection apparatus of the magnetic sensor detection signal which concern on embodiment of this invention. It is a top view with which it uses for the detection method and detection apparatus of the magnetic sensor detection signal which concern on embodiment of this invention. FIG. 3 is a diagram for explaining a detection method and a detection apparatus for a magnetic sensor detection signal according to an embodiment of the present invention, and is an end view of a cut surface taken along line II shown in FIG.

Explanation of symbols

11: Magnetized region 13: Magnetized carrier 15: Running surface 17: Magnetic sensor 18a: Opposing magnetic sensor 18b: Non-opposing magnetic sensor 19: Correction means 21: Magnetic sensor array 22: Drive circuit 23: Magnetic domain 25, 39: Amplifying circuit 29 41: A / D converter 32: control unit 33: storage unit 35: processing unit 36: determination unit 37: optical sensor

Claims (6)

Actuating a plurality of magnetic sensors arranged adjacent to each other in an array in a direction perpendicular to the traveling direction of the magnetic carrier having a magnetized region;
By this operation, an output signal corresponding to the magnetic field strength from the magnetic field directly opposite to each magnetic sensor and the magnetic field strength adjacent to the magnetic field adjacent to the magnetic field is extracted from each magnetic sensor. ,
Correction of the adjacent signal component caused by the adjacent magnetic field strength is performed on each output signal, and the facing signal component caused by the facing magnetic field strength is output as a detection signal of each magnetic sensor. A method for detecting a magnetic sensor detection signal. In the detection method of the magnetic sensor detection signal according to claim 1,
The plurality of magnetic sensors include n magnetic sensors arranged in order from the first to the n-th (n is a natural number excluding 0), facing the magnetic carrier,
The output signal taken out by the i-th magnetic sensor arranged at the i-th (i is a natural number of 1 <i <n) of the n magnetic sensors is A _i , and the i-th pair of magnetic domains facing the i-th magnetic sensor. B _i , a correction signal α (α is a real number where 0 <α <1), and the i−1 adjacent magnetic domain and the i + 1 adjacent magnetic domain adjacent to the i th positive magnetic domain Are adjacent signal components αB _i−1 and αB _{i + 1} ,
The output signal taken out by the first magnetic sensor arranged first among the n magnetic sensors is A ₁ , and the signal component directly due to the first facing magnetic domain facing the first magnetic sensor is B ₁ , Further, the adjacent signal component due to the second adjacent magnetic domain adjacent to the first directly facing magnetic domain is αB ₂ ,
An output signal taken out by the n-th magnetic sensor arranged in the n-th position among the n magnetic sensors is A _n , and a direct signal component caused by the n-th direct magnetic domain facing the n-th magnetic sensor is B _n , Further, an adjacent signal component caused by the (n−1) th adjacent magnetic domain adjacent to the nth positive magnetic domain is αB _n−1 , and the expression A _i = B _i + αB _i−1 + αB _{i + 1} (1 <i <n)
A ₁ = B ₁ + αB ₂ (i = 1)
A _n = B _n + αB _n-1 (i = n)
In addition, by using the value of A _i (i is a natural number of 1 ≦ i ≦ n) taken out by the n magnetic sensors, B _i (i is a natural number of 1 ≦ i ≦ n) is calculated, A detection method of a magnetic sensor detection signal, wherein the direct signal component is output as a detection signal of each of the magnetic sensors. In the detection method of the magnetic sensor detection signal according to claim 2,
Detecting the width of the magnetic sensor in the arrangement direction of the magnetic carrier using an optical sensor,
A detection method of a magnetic sensor detection signal, wherein the n magnetic sensors are selected from the plurality of magnetic sensors in correspondence with the detected width. A plurality of magnetic sensors operating on a magnetic carrier having a magnetized region and arranged adjacent to each other in an array in a direction perpendicular to the traveling direction of the magnetic carrier;
Correction means for correcting the output signal of each magnetic sensor and outputting a detection signal,
The plurality of magnetic sensors correspond to the magnetic field strength from the magnetic field directly opposite to each magnetic sensor and the magnetic field strength from the magnetic field adjacent to the magnetic field adjacent to the magnetic field. Take the output signal,
The correction means corrects an adjacent signal component caused by the adjacent magnetic field strength for each of the output signals, and outputs a facing signal component caused by the facing magnetic field strength as the detection signal, respectively. An apparatus for detecting a magnetic sensor detection signal. A detection device for a magnetic sensor detection signal according to claim 4,
The plurality of magnetic sensors include n magnetic sensors arranged in order from the 1st to the n-th (n is a natural number excluding 0), facing the magnetic carrier,
The correction means includes a storage unit and a processing unit,
The storage unit is the i (i is 1 <i <natural number n) directly facing an output signal taken out is the i-th magnetic sensor disposed in th A _i, the i-th magnetic sensor of the n-number of the magnetic sensors The direct signal component resulting from the i-th positive magnetic domain is B _i , the correction coefficient is α (α is a real number of 0 <α <1), and the (i-1) -th adjacent magnetic domain adjacent to the i-th direct magnetic domain and the The adjacent signal components resulting from the i + 1 adjacent magnetic domain are αB _i−1 and αB _{i + 1} ,
The output signal taken out by the first magnetic sensor arranged first among the n magnetic sensors is A ₁ , and the signal component that is directly opposite to the first magnetic sensor is B ₁ , Further, the adjacent signal component due to the second adjacent magnetic domain adjacent to the first directly facing magnetic domain is αB ₂ ,
An output signal taken out by the n-th magnetic sensor arranged in the n-th position among the n magnetic sensors is A _n , and a direct signal component caused by the n-th direct magnetic domain facing the n-th magnetic sensor is B _n , Further, an adjacent signal component caused by the (n−1) th adjacent magnetic domain adjacent to the nth positive magnetic domain is αB _n−1 , and the expression A _i = B _i + αB _i−1 + αB _{i + 1} (1 <i <n)
A ₁ = B ₁ + αB ₂ (i = 1)
A _n = B _n + αB _n-1 (i = n)
Is stored in advance,
The processing unit uses a value of A _i (i is a natural number of 1 ≦ i ≦ n) extracted by the n magnetic sensors from the equation read from the storage unit, and B _i (i is 1). ≦ i ≦ n (natural number). A magnetic sensor detection signal detection device. A detection device for a magnetic sensor detection signal according to claim 5,
An optical sensor for detecting the width of the magnetic carrier in the arrangement direction of the magnetic sensors and selecting the n magnetic sensors from the plurality of magnetic sensors corresponding to the detected width is provided. Magnetic sensor detection signal detection device.

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