JP6103848B2 - Foreign object detection device - Google Patents

Description

The present invention relates to a foreign object detection device that detects a foreign object (metal) that is mistakenly mixed into an object to be inspected by a magnetizer such as a magnet and uses residual magnetism of the magnetized metal, and includes a plurality of inspection lanes. The present invention relates to a foreign object detection apparatus provided.

  Conventionally, as a foreign matter detection device, an X-ray foreign matter detection device that irradiates an object to be inspected with X-rays and detects foreign matter in the inspection subject from the amount of X-ray transmission, and a magnetic field by the object to be inspected being conveyed There is known a metal detection device that detects a metal in an object to be inspected by a change in the angle. These foreign matter detection devices inspect the presence of foreign matter in the inspection object flowing through the conveyance path, sort the inspection object into non-defective products and defective products based on the inspection results, and remove only defective products from the conveyance path. Is excluded.

Further, the foreign substance inspection apparatus is provided with a substantially plate-shaped partition member that is long along the transport direction on the transport surface that the object to be inspected is transported, and the partition member makes the transport surface perpendicular to the transport direction (
In some cases, a plurality of inspection lanes are formed by dividing in the width direction of the conveyance surface. According to this foreign matter inspection apparatus, for example, a bulky inspection object such as a winner sausage or chicken nugget is inspected for each inspection lane, and the inspection object is sorted into a non-defective product and a defective product. For this reason, the number of inspected objects to be inspected in one inspection lane is reduced, and the ratio of non-defective products that are mixed with inspected inspected objects that are discharged as defective products is reduced to improve the yield. be able to. Also, some of the plurality of inspection lanes can be used as re-inspection lanes.

JP 2010-139725 A

However, since the foreign object detection apparatus of Patent Document 1 uses an X-ray sensor for foreign object detection, the apparatus needs to have a shielding structure so that X-rays do not leak from the inside of the apparatus. Alternatively, since the carry-out port is open, the conveyance direction cannot be shortened to prevent X-ray leakage, and the apparatus becomes large. In addition, since X-rays are irradiated in a fan shape from the X-ray source toward the X-ray detector in the width direction of the transport surface, the intensity of the X-rays differs at the center and end in the width direction of the transport surface. In order to reduce the influence, the X-ray source needs to be separated from the conveyance surface to some extent. Therefore, when increasing the inspection lane, the X-ray source needs to be further away from the transport surface in order to widen the inspection width in the width direction of the transport surface, resulting in a larger apparatus.

As described above, there is a problem that the size of the foreign object detection apparatus that detects a foreign object by forming a plurality of inspection lanes divided in the width direction of the transport surface is large. For this reason, a foreign object detection device that can be inspected in a plurality of inspection lanes in a small space has been desired by a user who wants to detect only metal as a foreign object, since the inspection object such as a tablet is relatively small.

Therefore, the present invention has been made in view of the above situation, and an object of the present invention is to provide a foreign object detection apparatus that can perform inspection for each of a plurality of inspection lanes in a small space.

In order to solve the above problems, a foreign object detection device according to the present invention has (1) a plurality of conveyance paths partitioned in parallel with the conveyance direction by a partition that divides the conveyance surface in a direction orthogonal to the conveyance direction. A conveying means for conveying the inspection object using the conveying path as an inspection lane; a magnetizing means for magnetizing a metal in the inspection object conveyed by the conveying means in a predetermined magnetization direction; and downstream of the magnetizing means. Is provided for each of the inspection lanes in the magnetic detection space, and has a sharp directivity in the magnetization direction by the magnetizing means, and the residual magnetic component of the metal in the inspection object magnetized by the magnetizing means. A magnetic sensor for detecting; shielding means for shielding an external magnetic field in the magnetization direction that enters the inside of the magnetic detection space; and the presence or absence of metal in the inspection object based on a signal from the magnetic sensor in the inspection lane. Judge every Characterized by comprising a constant section.

  With this configuration, a magnetic sensor having sharp directivity in the magnetization direction of the remanent magnetism of the metal in the inspection object magnetized by the magnetizing means is provided for each inspection lane. The residual magnetic component of the metal can be detected from an inspection object transported on another inspection lane in a state where the influence of magnetism is small, and inspection can be performed for each of the plurality of inspection lanes with a small space.

  In addition, since a shield hand is provided to shield the external magnetic field in the magnetization direction that enters the inside of the magnetic detection space, it is possible to shield the noise due to the external magnetic field that is not the residual magnetism of the metal in the inspection object. It is possible to detect the metallic foreign matter inside with high accuracy.

Further, the foreign matter detecting apparatus according to the present invention, (2) conveying said partition is a is constituted by a partition member provided near the conveying surface, the conveying means, the object to be inspected by the conveyance belt characterized in that it is constituted by a belt conveyor for.

  With this configuration, a plurality of inspection lanes can be formed with a simple configuration, and the width direction of the conveyance means orthogonal to the configuration conveyance direction can be kept short.

  Moreover, the foreign material detection apparatus according to the present invention is characterized in that (3) the transport means is formed of a slide having a transport path inclined downward with respect to the transport direction.

 With this configuration, the object to be inspected can be transported by free fall without a drive source, and inspection can be performed for each of a plurality of inspection lanes with more space.

Further, the foreign matter detecting apparatus according to the present invention, (4) the conveying means, a plurality of grooves are formed in the conveying direction, characterized in that it is constituted by a conveying path which the side walls of the groove was set to the partition .

 With this configuration, since the side wall of the groove is a partition, it can be partitioned without a gap from the adjacent inspection lane, and a part of the object to be inspected can be transported without being caught in the gap of the partition.

  The foreign matter detection apparatus according to the present invention is characterized in that (5) the magnetizing means and the magnetic sensor are provided on a side wall of the groove.

  With this configuration, the width direction of the transport unit orthogonal to the transport direction can be kept short.

Moreover, the foreign material detection apparatus according to the present invention is characterized in that (6) the magnetizing means and the magnetic sensor are provided below a conveying surface of the conveying means.

With this configuration, the height direction of the transport unit orthogonal to the transport direction can be kept low.

In the foreign matter detection apparatus according to the present invention, (7) the magnetizing means is provided across the plurality of inspection lanes below a transport surface of the transport means.

  With this configuration, the magnetizing means can be simplified.

  In addition, the foreign matter detection apparatus according to the present invention includes (8) a core that provides an elongated magnetic path with respect to the magnetic field measured by the magnetic sensor, and a detection coil wound around the core. It is comprised from the orthogonal type | mold fluxgate sensor which supplies an alternating current to the said core so that a moment may face the orthogonal direction periodically with respect to the longitudinal direction of the said core.

 With this configuration, the magnetic sensor can be miniaturized and the width of the inspection lane can be kept small, so that the inspection can be performed for each of the plurality of inspection lanes with more space.

  According to the present invention, in a foreign object detection apparatus that forms a plurality of inspection lanes for inspection, metal foreign objects can be detected in each inspection lane without increasing the size of the apparatus.

It is a perspective view which shows the structure of the foreign material detection apparatus which concerns on 1st Embodiment. It is a block diagram which shows typically the structure of the foreign material detection apparatus which concerns on 1st Embodiment. (A) It is a top view of the foreign material detection apparatus concerning 1st Embodiment, (b) is sectional drawing of B-B ', (c) is sectional drawing of A-A'. It is a figure which shows the structure of the other magnetizing means in the foreign material detection apparatus which concerns on 1st Embodiment. It is a circuit block diagram of the magnetic detection part in the foreign material detection apparatus which concerns on 1st Embodiment. It is a perspective view which shows the structure of the foreign material detection apparatus which concerns on 2nd Embodiment. It is a top view which shows the structure of the foreign material detection apparatus which concerns on 2nd Embodiment. (A) is a top view which shows the other structure in the foreign material detection apparatus which concerns on 2nd Embodiment, (b) is sectional drawing of BB 'of (a), (c) is A- of (a). It is sectional drawing of A ''.

  Embodiments of the present invention will be described below with reference to the drawings.

  1. First Embodiment (FIG. 1) FIG. 1 is a diagram showing a first embodiment of the present invention. First, the configuration will be described.

  As shown in FIG. 1 and FIG. 2, the foreign object detection device 1 is, for example, as a transport unit that transports an inspection object W having a thin cylindrical shape containing food in a tablet or plastic container in a plurality of inspection lanes 3. The belt conveyor 2, the magnetizing means 5 for magnetizing the metal m in the inspection object W in a predetermined magnetization direction, and the predetermined for detecting the residual magnetism of the metal m in the inspection object W magnetized by the magnetizing means 5. Sensors 6a to 6e having a sharp directivity in the magnetization direction, magnetic shield 7 for shielding noise caused by an external magnetic field that is not the residual magnetism of metal m in the inspection object, and detection signals from the magnetic sensors 6a to 6e. Based on this, there is provided determination means 11 for determining the presence or absence of the metal m in the inspection object W.

  The belt conveyor 2 includes rollers 2b and 2b at both ends, respectively, and an endless conveyance belt 2b is wound around the rollers 2b and 2b. One of the rollers 2b is connected to a drive motor (not shown), and the conveyor belt 2b is rotated by the drive force of the drive motor. At this time, the belt surface of the conveyance belt 2c becomes the conveyance surface 2a of the inspection object W.

A plurality (six) of substantially rectangular plate-like partition members 4 extending in the transport direction X are provided on the transport surface 2 a of the belt conveyor 2 in proximity to the transport surface.

The partition member 4 is formed of a resin such as polycarbonate or acrylic so that the substantially whole plate-like portion is formed so as not to affect the magnetic sensor. As shown in FIG. 1, the partition member 4 includes the transport surface 2a. The direction perpendicular to the transport direction X on the horizontal plane (the width direction Y of the transport surface 2a)
) To form a plurality (five) of transport paths 3a to 3e, and the divided transport paths 3a to 3e can be used as inspection lanes 3 to independently check for the presence of metal m. And

At a predetermined position on the upstream side of the conveying means 2, a permanent magnet is installed for each lane of the inspection lane 3 as the magnetizing means 5 for magnetizing the metal m in the object to be conveyed. As shown in FIG. 3B, the permanent magnet has a magnetic pole below the conveying surface 2a so that the metal m in the object to be inspected is magnetized in a direction perpendicular to the conveying surface 2a (the height direction in FIG. 1). It is arranged near the side.

  When the magnetic pole (for example, N pole) of the permanent magnet is arranged in the vicinity of the lower side of the transport surface 2a in this way, when the inspection object passes just above the magnetic pole, the metal m in the inspection object is changed from the N pole to the S pole. Magnetized in a direction perpendicular to the transport surface 2a by a strong magnetic field directed to the pole.

Further, any arrangement may be used as long as the metal m in the inspection object W is magnetized in the same direction as described above. For example, as shown in FIG. 4, the magnetic poles cross each inspection lane 3. In addition, common to each lane arranged on the upper side of the conveyance surface 2a so that the north pole common to each inspection lane 3 arranged near the lower side of the conveyance surface 2a faces the upward magnet with the object to be inspected in between. The magnetizing means 5 may be composed of a magnet with the S pole facing downward. Further, the magnetizing means 5 may be configured by only one magnet common to each inspection lane 3 in which the N pole is disposed in the vicinity of the lower side of the conveyor belt 2b. Further, the magnetic poles of all the above permanent magnets may be arranged in reverse, that is, the N pole may be arranged at the S pole position and the S pole may be arranged at the N pole position. Here, although the permanent magnet has been described as the magnetizing means 5, other magnetizing means such as an electromagnet may be used.

The magnetic sensors 6 a to 6 e are provided for each inspection lane 3 in the magnetic detection space 8 that is located on the downstream side of the magnetizing unit 5 that is not directly affected by magnetism from the magnetizing unit 5. The magnetic sensors 6 a to 6 e indicate the residual magnetism of the metal m with respect to the inspection object W conveyed on the conveyance path of the inspection lane 3 and the magnetic field from the inspection object W conveyed on the adjacent inspection lane 3. It has a sharp directivity in the magnetization direction (the height direction in FIG. 1) by the magnetizing means 5 so as to detect without being affected.

As shown in FIG. 3C, the magnetic sensors 6a to 6e have a sharp directivity in the height direction (direction indicated by the arrow H) of the inspection object W, which is the magnetization direction by the magnetizing means. For this reason, the magnetic sensors 6a to 6e can detect only the component in the H direction of the magnetic flux of the metal m in the inspection object W. In the present embodiment, the magnetic sensors 6a to 6e are composed of orthogonal flux gate sensors shown in FIG.

Here, the fluxgate sensor is a small high-sensitivity sensor that can measure a magnetic field of 10 pT to a geomagnetic level in a frequency band from a static magnetic field to a low frequency without requiring cooling or heating. In a fluxgate sensor, a core that provides an elongated magnetic path for a magnetic field to be measured and a detection coil wound around the core are basic elements of the sensor head.

Since the magnetic sensors 6a to 6e have the same configuration, a specific configuration of the magnetic sensor 6a will be described below.

As shown in FIG. 5, in the magnetic sensor 6a configured as the orthogonal fluxgate sensor of this embodiment, a coil that cancels the input magnetic field is provided as the detection coil 63, and the residual magnetic field is detected by the high sensitivity sensor. In addition, a negative feedback configuration is adopted in which a zero position method is employed in which the magnitude of the input magnetic field is detected from the magnitude of the current used to cancel the input magnetic field so that the residual magnetic field becomes substantially zero. In the negative feedback configuration employing the zero position method, there is an advantage that the linearity of the zero point portion is good and the dynamic range is widened.

  The sensor head 61 employs a U-shaped amorphous magnetic wire as the core 62, and one end of the detection coil 63 is grounded with a low resistance. In order to simplify the structure, the detection coil 63 is also used as a negative feedback coil. The exciting current of the core 62 is taken directly from the signal generator 64 having an output resistance of 50Ω for simplicity. Excitation applies a necessary DC bias voltage (Vdc) to a sine wave voltage (Vac) of 100 kHz. Since the detection voltage from the detection coil 63 is 100 kHz, which is the same as the excitation frequency, it is input to the preamplifier 65 by AC coupling, balanced demodulated by the synchronous detector circuit 66, and then by a subsequent smoothing filter (cutoff frequency≈100 Hz). Conversion to direct current. The signal converted into direct current is amplified by a band-limited error amplifier 67 using 0 V as a reference voltage, and a negative feedback current for cancellation is superimposed on the detection winding via the high resistance Rf. Here, the reason why the resistance value of the high resistance Rf is increased is to convert the negative feedback current into a voltage with high sensitivity, and to prevent the feedback circuit from becoming a load when viewed from the detection coil 63. The selection of the time constant of the error amplifier 67 on the input side of the preamplifier 65 and the negative feedback circuit side is set in the range of 1 / (C1R1)> 10 / (C2R2). The voltage across the high resistance Rf is extracted by a voltage follower (not shown) and then output through a subtraction circuit and a 60 Hz notch filter. The magnetic sensor 6a has a U-shaped core 62 made of amorphous wire, thereby preventing magnetic flux changes that occur independently of the input magnetic field at the left and right legs of the core 62 from occurring and preventing an offset from occurring. Can be done. The length of the core 62 of the magnetic sensor 6a is optimally about 1.5 to 3 cm. This is because, if the core 62 is lengthened, the resolution can be increased and the directivity can be sharpened, while an insensitive body is generated at the center.

  In addition, although the example of the orthogonal fluxgate sensor was demonstrated as the magnetic sensors 6a-6e, what is necessary is just a magnetic sensor with high directivity, the magnetic sensor using a pick-up coil, the magnetic impedance sensor, and the magnetism using a Hall element. A sensor or the like may be used.

  The magnetic shield 7 has not only the direction of sharp directivity of the magnetic sensors 6a to 6e (indicated by an arrow H in FIG. 3C) but also the width direction of the transport surface 2a (indicated by an arrow Y in FIG. 3C). And a tunnel structure in which the direction of conveyance of the inspection object is opened with an integral configuration surrounding the magnetic detection space 8 on each inspection lane 3 and the magnetic sensors 6a to 6e. Yes.

  Further, the foreign object detection device 1 includes a control unit 10 having an AD converter and a determination unit 11 (not shown) and a display unit 12 for displaying the determination result. Although a specific hardware configuration is not illustrated, the control unit 10 includes an EEPROM (Electronically Erasable and Programmable Read Only Memory), a hard disk, and the like as a nonvolatile memory in addition to a CPU, a ROM, a RAM, and an input / output interface circuit. In accordance with a predetermined metallic foreign matter detection control program stored in a ROM, EEPROM, hard disk or the like, based on detection signals from the magnetic sensors 6a to 6e, determination threshold values stored in a nonvolatile manner in the EEPROM, and the like Thus, it is determined whether or not the metal m is mixed in the inspection object W.

  Detection signals from the magnetic sensors 6 a to 6 e are respectively input to AD converters individually provided for the magnetic sensors 6 a to 6 e, and while the inspection object W passes through the magnetic detection space 8. The detection signals from the magnetic sensors 6a to 6e are converted from analog signals to digital signals in the AD converters, respectively, and a determination threshold value preset by the determination means 12 provided for each of the magnetic sensors 6a to 6e is set. The presence or absence of the metal m is determined with reference to it. The determination result by the determination unit 11 is displayed on the display unit 12.

  The determination unit 11 determines the presence or absence of the metal m in the inspection object W based on detection signals from the plurality of magnetic sensors 6a to 6e, and outputs the result to the display unit 12.

  Next, the operation will be described.

  As shown in FIG. 1, when the inspection object W passes through the magnetic detection space 8, the detection signals from the magnetic sensors 6a to 6e are converted from analog signals to digital signals in AD conversion (not shown), and the magnetic sensors 6a to 6e. The determination unit 11 is provided for each 6e.

  Assuming that the detection signals from the magnetic sensors 6a to 6e are the detection signals 6as to 6es, the determination unit 11 compares the detection signals 6as to 6es with the determination threshold value, and exceeds the determination threshold value. If there is a detection signal, a determination result indicating that metal is mixed is output to the display unit 12. Upon receiving the determination result, the display unit 12 displays the presence or absence of metal contamination in the inspection object W for each inspection lane 3.

  As described above, the foreign object detection device 1 according to the present embodiment has a plurality of conveyance paths that are partitioned in parallel with the conveyance direction, and the belt that conveys the inspection object W using the conveyance paths as inspection lanes 3. An inspection lane in the conveyor 2, a magnetizing means 5 for magnetizing the metal m in the inspection object W conveyed by the belt conveyor 2 in a predetermined magnetization direction, and a magnetic detection space 8 positioned downstream from the magnetizing means 5 Magnetic sensors 6a to 6e provided for every three, which have a sharp directivity in the magnetization direction by the magnetizing means 5 and detect the residual magnetic component of the metal m in the object W magnetized by the magnetizing means 5. The presence or absence of the metal m in the object W to be inspected for each inspection lane 3 based on the signals from the magnetic sensors 7a to 6e and the magnetic shield 7 that shields the external magnetic field in the magnetization direction entering the magnetic detection space 8 Having the judging means 11 for judging It is a symptom.

  For this reason, a magnetic sensor having sharp directivity in the magnetization direction of the residual magnetism of the metal m in the inspection object W magnetized by the magnetizing means 5 is provided for each inspection lane 3. It is possible to detect the residual magnetic component of the metal m in the inspection object W from the inspection object W transported on another inspection lane 3 in a state where the influence of magnetism is small, and to inspect each of the plurality of inspection lanes 3 in a space-saving manner. it can.

  In addition, since the magnetic shield 7 is provided to shield the external magnetic field in the magnetization direction penetrating into the magnetic detection space 8, noise due to the external magnetic field that is not the residual magnetism of the metal m in the inspection object W can be shielded. It is possible to detect a metal foreign object in the inspection object W with high accuracy.

  Furthermore, since the plurality of inspection lanes 3 are formed by dividing the conveyance surface 2a in the direction orthogonal to the conveyance direction by the partition member 4 provided close to the conveyance surface 2a, the plurality of inspection lanes 3 can be formed with a simple configuration. The width direction of the belt conveyor 2 can also be suppressed short.

  Moreover, since the orthogonal type fluxgate sensor which is a small high-sensitivity sensor is used for the magnetic sensors 6a to 6e, the width of the inspection lane 3 can be further reduced, and the space for each of the plurality of inspection lanes 3 can be further reduced. Can be inspected.

2. Second Embodiment The foreign object detection device 21 of the present example is different from the first embodiment in that the transport unit 22 does not have a drive source and is a slide inclined downward with respect to the transport direction. Since the other configuration is the same as that of the first embodiment, a different part from the configuration of the first embodiment will be described, and regarding the other configuration, the portion corresponding to the configuration of the first embodiment is shown in the first embodiment in the drawing. The same reference numerals are used, and the description of the first embodiment is appropriately incorporated as long as there is no contradiction, and the description thereof is omitted.

  In the present embodiment, as shown in FIGS. 6 and 7, the foreign object detection device 21 includes a conveying means 22 in which a plurality of grooves are formed, a magnetizing means 5 for magnetizing a metal in the inspection object W, Magnetic sensors 6a to 6e for detecting the residual magnetic component of the metal m in the inspection object W magnetized by the magnetizing means 5, and a magnetic shield for shielding noise caused by an external magnetic field that is not the residual magnetism of the metal m in the inspection object. 7 and determination means 11 (not shown). In addition, an alignment supply device 30 for supplying the inspection object in alignment with the conveyance means 22 and the conveyance groove of the conveyance means is disposed in front of the conveyance means 22.

  The conveying means 22 is constituted by a slide in which grooves that are parallel to the conveying direction and inclined downward with respect to the conveying direction form conveying paths 23 a to 23 e for conveying the inspection object W. The slide is integrally formed of a resin such as polycarbonate or acrylic so as not to affect the magnetic sensors 6a to 6e provided in the vicinity of the conveyance path. Hereinafter, the inspection object lane 23 is used as an inspection lane 23, and the inspection object W is inspected for the presence or absence of metal in the inspection object while sliding freely along the conveyance paths 23a to 23e. The plurality of inspection lanes 23 are partitioned by the side walls of the conveyance grooves.

The permanent magnet as the magnetizing means 5 has a magnetic pole disposed near the lower side of the conveying surface 22a on the upstream side of the conveying means 22 so that the metal m in the inspection object is magnetized in a direction orthogonal to the conveying surface 22a. ing. In addition, the magnetic sensors 6a to 6e are arranged below the transport surface 2a in the magnetic detection space 8 located on the downstream side of the magnetizing means 5 that is not directly affected by magnetism from the magnetizing means 5, and in the inspection lane 23. It is provided for each.

  In the foreign matter detection device 21, since the inspection lane 23 is partitioned by the side wall of the conveyance groove, as shown in FIGS. 8A to 8C, the permanent magnet as the magnetizing means 5 and the magnetic sensor 6a. ˜6e can be arranged on the side wall of the conveyance groove.

  In this case, the permanent magnets are arranged so that the polarities of the permanent magnets are different at both ends of the conveying groove so that a strong magnetic field crosses the conveying groove, and the magnetization direction is orthogonal to the conveying direction X on the conveying surface (FIG. 8 (a The magnetic sensors 6a to 6e are preferably arranged so as to have sharp directivity in the same direction.

  Further, when the length of the side wall (partition width) of the transport groove is shortened in the magnetization direction, the magnetic sensor is not affected by the magnetic field from the inspection object W transported on the adjacent inspection lane 23. It is preferable to provide a magnetic shield between 6 a to 6 e and the adjacent inspection lane 23 to shield noise in the magnetization direction from the inspection object W transported on the adjacent inspection lane 23.

The alignment supply device 30 is a device for sequentially aligning the inspection objects in the conveyance grooves of the conveyance means 22 and conveying and supplying them. The alignment supply device 30 is inclined downward with respect to the conveyance direction and is aligned downstream from the upstream loading portion 31. The object to be inspected is conveyed to the portion 32 by free fall.

Since the alignment unit 32 is formed with a conveyance path having the same width as the conveyance groove of the conveyance unit 22, the inspection objects to be collectively loaded into the carry-in unit 31 are distributed along the conveyance path of the alignment unit 32 and are conveyed by the conveyance unit 22. To be supplied.

As described above, in the foreign object detection device 21 according to the second embodiment of the present invention, the object W distributed to the inspection lanes 23 by the alignment supply device 30 and carried into the transport means 22 is covered by free fall. While the inspection object slides on the conveyance path, the presence or absence of metal in the inspection object is inspected for each inspection lane 23.

  As described above, the foreign object detection device 21 according to the second embodiment of the present invention can transport an object to be inspected by a free fall that does not have a drive source, and can perform inspection for each of a plurality of inspection lanes 23 in a smaller space. Can do.

Further, if the magnetizing means 5 and the magnetic sensors 6a to 6e are arranged on the side wall of the transport groove, the height in the direction orthogonal to the transport surface 23a can be kept low.

  As described above, the foreign object detection device of the present invention has an effect of being able to inspect each of a plurality of inspection lanes in a space-saving manner, and detects a plurality of metal foreign objects in an object to be inspected, such as food and medicine. This is useful for a foreign object detection device having an inspection lane.

DESCRIPTION OF SYMBOLS 1, 21 ... Foreign object detection device 2, 22 ... Conveyance means 3, 23 ... Inspection lane 4 ... Partition member 5 ... Magnetization means 6a-6e ... Magnetic sensor 7 ... Magnetic shield (shielding member)
DESCRIPTION OF SYMBOLS 8 ... Magnetic detection space 10 ... Control part 11 ... Determination means 12 ... Display part

Claims (8)

Conveying means (2, 22) having a plurality of conveying paths partitioned in parallel with the conveying direction by partitions that divide the conveying surface in a direction perpendicular to the conveying direction, and conveying the inspection object using the conveying path as an inspection lane )When,
Magnetizing means (5) for magnetizing a metal in the inspection object conveyed by the conveying means in a predetermined magnetization direction;
Inspected in the magnetism detection space (8) located downstream from the magnetizing means, provided for each of the inspection lanes, having a sharp directivity in the magnetization direction by the magnetizing means and magnetized by the magnetizing means. A magnetic sensor (6a-6e) for detecting the remanent magnetic component of the metal in the object;
Shielding means (7) for shielding an external magnetic field in the magnetization direction entering the inside of the magnetic detection space;
A foreign matter detection apparatus comprising: a determination unit (11) that determines, for each inspection lane, the presence or absence of metal in the inspection object based on a signal from the magnetic sensor. The partition is constituted by a partition member provided close to the transport surface;
The conveying means, the foreign matter detecting device according to claim 1, characterized in that it is constituted by a belt conveyor for conveying the object to be inspected by the conveyance belt. The foreign matter detection apparatus according to claim 1, wherein the transport unit includes a slide having a transport path inclined downward with respect to the transport direction . Said conveying means, a plurality of grooves are formed in the conveying direction, foreign object detecting device according to sidewalls of the groove to claim 3, characterized in that it is constituted by a transport path and the partition.   The foreign object detection device according to claim 3, wherein the magnetizing unit and the magnetic sensor are provided on a side wall of the groove.   The foreign object detection device according to claim 1, wherein the magnetizing unit and the magnetic sensor are provided below a conveyance surface of the conveyance unit.   The foreign object detection device according to claim 6, wherein the magnetizing means is provided across the plurality of inspection lanes below a conveyance surface of the conveyance means.   A core that provides an elongated magnetic path to a magnetic field measured by the magnetic sensor; and a detection coil wound around the core, wherein the magnetic moment of the core is periodically orthogonal to the longitudinal direction of the core The foreign matter detection device according to claim 1, wherein the foreign matter detection device is configured by an orthogonal fluxgate sensor that supplies an alternating current to the core so as to face the direction.

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