JP6575019B2 - Magnetic metal foreign object detection device and detection method - Google Patents

Description

  The present invention relates to a magnetic metal foreign object detection device and detection method, and more particularly, a detection apparatus suitable for detecting a magnetic metal foreign object contained in an individual object to be inspected contained in a container such as a bottle. And a detection method using.

  It is well known to detect a magnetic metal foreign object by measuring the magnetic force of a magnetic metal foreign object contained in an inspection object traveling in one direction intermittently or continuously with a plurality of magnetic sensors. In addition, when the inspection object is a fluid such as a beverage and the magnetic sensor is installed inside the magnetic shield box forming the magnetic shield space, the inspection object passes through the magnetic shield box. It is known to measure the magnetic force of magnetic metal foreign matter.

  For example, Japanese Patent Laying-Open No. 2005-351804 (Patent Document 1) describes an apparatus for detecting a magnetic foreign substance in a liquid container in which a fluid substance is sealed. In this apparatus, a magnetic sensor is installed at the bottom or side of the transport path of the liquid container. The magnetic sensor is installed in a space created by a magnetic shield for shielding it from an external magnetic field. The magnetic shield space extends along the conveyance path, and has a front opening and a rear opening, and a liquid container placed on the conveyance belt can be introduced into the magnetic shield space.

  Japanese Unexamined Patent Publication No. 2000-171443 (Patent Document 2) describes a magnetic foreign substance detection method and a detection apparatus. The object to be inspected is a long rod-like or linear object that continuously travels in the longitudinal direction, and the magnetic variation of the object to be inspected is measured by a magnetic sensor, and the magnetism contained in the object to be inspected. Detect foreign objects. In this detection device, a magnetic sensor and an object to be inspected passing through the vicinity of the magnetic sensor are surrounded by a magnetic shielding device.

JP 2005-351804 A JP 2000-171443 A

  When the object to be inspected is transported in one direction by the conveying means or travels continuously in one direction, the magnetic shield box in which the magnetic sensor is installed usually has the object to be inspected. Two openings, an inlet and an outlet, are required to pass through. Further, when the object to be inspected is a fluid filled in a vertically long container such as a bottle, the opening tends to be large because the container is normally passed vertically through the opening. However, the larger the opening of the magnetic shield box, the more easily the magnetism generated in the external environment enters as magnetic noise, and as a result, the detection of the weak magnetic force from the fine magnetic metal foreign matter among the magnetic metal foreign matter is detected. There is a problem that becomes difficult.

  Accordingly, the present invention is to provide a magnetic metal foreign object detection device and a detection method that are improved so that the openings in the magnetic shield box for forming the magnetic shield space can be reduced or reduced. I have to.

  In order to solve the above problems, one of the objects of the present invention is to sequentially measure the magnetic force of the inspection object while moving a plurality of individually prepared inspection objects in one direction. This is a detection device for detecting magnetic metal foreign matter contained in each inspection object.

In the detection apparatus, the first aspect of the present invention is characterized as follows. The detection device includes a magnetic shield box having a bottom portion, a ceiling portion, and a side wall portion connected to both of them to form a magnetic shield space, and the magnetic metal foreign matter installed inside the magnetic shield box. A plurality of magnetic sensors for measuring the magnetic force of the magnetic signal, signal processing means for detecting the magnetic force of the magnetic metal foreign matter based on an output signal of the magnetic sensor, and a reciprocating mechanism, the magnetic shield box, An opening serving as an entrance for allowing the inspection object to enter and exiting for the inspection object is formed in the magnetic shield space, and the reciprocation mechanism causes the inspection object to reciprocate to cause the inspection object to reciprocate. The inspection object can be made to enter and leave the opening, and the magnetic sensor is configured to detect the inspection object that has entered the opening in the magnetic shield box. It is placed at the object and a position facing.
In the detection device, the second aspect of the present invention is characterized as follows. The detection device includes a magnetic shield box having a bottom portion, a ceiling portion, and a side wall portion connected to both of them to form a magnetic shield space, and the magnetic metal foreign matter installed inside the magnetic shield box. A plurality of magnetic sensors for measuring the magnetic force of the magnetic signal, signal processing means for detecting the magnetic force of the magnetic metal foreign matter based on an output signal of the magnetic sensor, and a reciprocating mechanism, the magnetic shield box, One opening is formed to serve as both an entrance for allowing the inspection object to enter the magnetic shield space and an exit for exiting the inspection object, and the reciprocating mechanism causes the magnetic shield box to reciprocate to move the object. The inspection object can enter and exit the opening, and the magnetic sensor enters the opening in the magnetic shield box. Wherein is installed at a position opposite to the object to be inspected was.

In order to solve the above problems, another object of the present invention is a method for detecting a magnetic metal foreign object.
In this detection method, the present invention is characterized in that a magnetic metal foreign matter contained in a plurality of objects to be inspected is detected using the detection apparatus according to the present invention.

  In the magnetic metal foreign object detection device and detection method according to the present invention, since the opening of the magnetic shield box in which the magnetic sensor is installed also serves as the entrance and exit of the object to be inspected, Compared to a conventional magnetic shield box in which the outlet is formed separately, intrusion of magnetic noise from the outside is reduced, and the accuracy of detecting the magnetic force from the magnetic metal foreign matter is improved.

The drawings illustrate certain embodiments of the invention according to the present disclosure and include selective and preferred embodiments as well as essential configurations of the invention.
The front view of the detection apparatus which concerns on this invention. The right view of the detection apparatus of FIG. The right view of a magnetism apparatus. Top view of the table. The VV arrow directional view of FIG. FIG. 2 is a block diagram for a detection device. FIG. 7 is a partial detail view of the block diagram of FIG. 6. The front view of an operation panel. The IX-IX line arrow directional view of FIG.

  The details of the magnetic metal foreign object detection device and the detection method using the device according to the present invention will be described below with reference to the accompanying drawings.

  In the front view and the right side view of the magnetic metal foreign object detection device 1 shown in FIGS. 1 and 2, the detection device 1 includes a device main body 2, an operation panel 3, a belt conveyor 4 as a conveying means, and a magnetizing means 5. And a transporting operation unit 8 and a reciprocating mechanism 13. The illustrated belt conveyor 4 has a motor 4a for driving the belt conveyor 4 and can run horizontally and continuously or intermittently in the machine direction MD. The belt conveyor 4 also has an upstream part A and a downstream part B, and a sorting unit 50 is attached to the downstream part B. A test object 100 such as a soft drink, a food, a detergent, or a medicine is filled in a container of an appropriate shape, for example, a cylindrical container W such as a bottle having an appropriate cross-sectional shape and size, and the individual test object. It becomes 100 and is placed on the belt conveyor 4 and proceeds in the machine direction MD. However, in order to facilitate understanding of the structure of the detection apparatus 1, in FIG. 1, the container W is shown only in the upstream portion A and not in the downstream portion B, but in FIG. The container W is shown in the downstream part B. The right side view of the detection device 1 is a view of the device 1 as viewed from the right side of FIG.

  In such a detection apparatus 1, when the container W passes through the magnetizing means 5, a magnetic metal foreign substance (not shown) mixed in the inspection object 100 is manifested with a magnetic force or a strengthened magnetic force. In the process in which the container W passes the post-magnetic force detection unit 23 (see FIGS. 5 and 7) in the apparatus main body 2, the magnetic force of the inspection object 100 is measured. The detection apparatus 1 also compares a preset threshold value with the measured magnetic force, and determines that the inspection object is a good product when the magnetic force is equal to or less than the threshold value. When the threshold value is exceeded, it is determined that the inspection object is defective. The results of these determinations are displayed on the display unit 35 in the operation panel 3. When the inspection object 100 is a defective product, the sorting unit 50 is operated by a signal from the magnetic force detection unit 23, and the container W filled with the inspection object 100 can be taken out from the belt conveyor 4.

  Further details of the detection device 1 are as follows. In addition to the magnetic force detection unit 23, the apparatus main body 2 includes a general control unit 26, a display unit 35, a setting unit 36, a storage unit 37, a driving operation unit 38, and an alarm transmitter 49 (see FIGS. 1 and 6) as will be described later. Have.

  In the belt conveyor 4, the operation restricting unit 6 and the magnetizing means 5 are incorporated in the upstream portion A. Between the upstream portion A and the downstream portion B, a transport operation unit 8 and a reciprocation mechanism 13 that allows the container W to move up and down are interposed.

The operation restricting unit 6 has a pair of struts 6 a facing each other in the width direction of the belt conveyor 4, and a pair of stoppers 6 b extending from each of the struts 6 a toward the width direction of the belt conveyor 4. The stopper 6b is a swing-type door that turns toward the downstream side around the column 6a. The upstream side of the column 6a, there is an optical sensor 7 which is formed by the light projecting unit 7a opposite to each other with respect to the belt conveyor 4 and the light receiving section 7b, the container W ₁ of the container W traveling downstream, spacing the container W ₂ subsequent to the container W _1, for example, the distance L between centers is monitored to or greater than a predetermined size. When the distance L between centers is less than the predetermined size, it is determined that the container W ₁ and the container W ₂ are too close, and a pair of stoppers 6b in the closed state as shown in FIG. 1, the belt conveyor 4 traveling container W ₂ even though it prevents the flow proceeds to the downstream side. When the center distance L becomes equal to or larger than a predetermined size, a pair of stoppers 6b is opened toward the downstream side, the container W ₂ thereby allowing the advancing with the belt conveyor 4 to the downstream side.

  FIG. 3 is a view of the magnetized means 5 of FIG. 1 when viewed from the downstream side of the belt conveyor 4. The magnetized means 5 includes a pair of permanent magnets 19 and 20 that face each other with the belt conveyor 4 interposed therebetween, and a yoke 22. A DC magnetic field is formed between the N pole of the permanent magnet 19 and the S pole of the permanent magnet 20, and when the container W placed on the belt conveyor 4 passes through the magnetizing means 5, it is included in the inspection object 100. The magnetic metal foreign material becomes magnetized or becomes magnetically reinforced and becomes easy to detect. The permanent magnets 19 and 20 can be replaced with electromagnets.

  1 and 2 again, the transport operation unit 8 includes an optical sensor 9, a rotating table 10, an electric rotary actuator 11 (see FIG. 4), and a magnetic shield box 12 (see FIG. 4). . However, although the optical sensor 9 is formed of a projector and a light receiver, only the projector is shown in the figure. The table 10 includes an upper table 10a and a lower table 10b having the same central axis (not shown), and each of the tables 10a and 10b can receive a container W from the outside in the radial direction. Recesses 65 and 66 are formed. The upper table 10 a and the lower table 10 b are also integrated through a plurality of support columns 67.

As is apparent in FIG. 4 is a top view of the upper table 10a of the table 10, the container W which is placed on the belt conveyor 4 moves the upstream portion A, for example, the container W ₁ is an upper table 10a in FIG. 1 Once received in the recess 65 of the optical sensor 9 detects the container W _1, to operate the electric rotary actuator 11. Then, the upper table 10a rotates clockwise 45 ° together with the lower table 10b, and the container W (for example, W ₂ in FIGS. 1 and 4) that is placed on the belt conveyor 4 and moves next is moved to the upper table 10a. Wait until it is received in the recess 65. When the next container W (W ₂ in FIGS. 1 and 4) is received in the recess 65, the upper table 10a and the lower table 10b rotate again by 45 °, and further the next container W (for example, FIGS. 1 and 4). Wait for W ₃ ) to be accepted. In this way, when the container W is rotated 90 ° in the clockwise direction D together with the table 10, the container W comes directly below the magnetic force detection unit 23 (container W ₁ in FIGS. 4 and 5). Since the electric rotary actuator 11 generates magnetic noise when it operates, it is covered with the magnetic shield box 12 so as not to affect the detection of metallic foreign matter. Incidentally, the distance L between the container W ₁ and the container W ₂ in the operation restricting unit 6 of FIG. 1 is controlled to be a required size, a table 10 of the container W is being rotated to move the machine direction MD This is to avoid a collision.

  Although the table 10 includes the upper table 10a and the lower table 10b, the container W can be stably held even when the container W is high in height, but depending on the height and shape of the container W Thus, the upper table 10a and the lower table 10b are made different in shape, an intermediate table or the like is added between the upper table 10a and the lower table 10b, or only one of the upper table 10a and the lower table 10b is used. Can do things.

As is clear from FIG. 5, which is a view taken along the line VV in FIG. 4, the reciprocating mechanism 13 includes an optical sensor 14 (see FIG. 1), a reciprocating unit 15, and an electric actuator 16. Yes. The reciprocating unit 15 in the illustrated example is a lifting platform that can be moved up and down in the vertical direction by placing the container W thereon. The optical sensor 14 is formed by a projector and a light receiver, but only the projector is shown in FIG. When the container W (see container W ₁ in FIG. 4) comes directly under the magnetic force detection unit 23, the light sensor 14 detects the container is W, the electric actuator 16 is operated, illustrating the reciprocating movement section 15 by arrows E It is raised manner, advancing the container W to the magnetic shield box 25 in the force detection unit 23 (see container W ₁ in FIG. 5). The electric actuator 16 is covered with a magnetic shield 17 because it generates magnetic noise when it operates.

In FIG. 5, the magnetic force detector 23 has a two-layer magnetic shield box 25 forming a magnetic shield space. Each of the layers of the magnetic shield box 25 is made of a highly permeable material such as permalloy, and an opening 60 penetrating the bottom 25a is formed in the bottom 25a. Magnetic Inside the shield box 25, each horizontal foundation of the magnetic sensor S ₁ -S 7 in the container W can face position coming enters through the opening 60 into the interior _(see also FIG. 9) attached to 70, is described below the magnetic sensor S ₈ is attached to the ceiling of the magnetic shield box 25. In the process in which the electric actuator 16 in the reciprocating mechanism 13 is activated and the container W (for example, the container W _{1 in} FIG. 5) enters the magnetic shield box 25, the reciprocating mechanism 13 is installed so as to be arranged at substantially equal intervals in the circumferential direction of the container W. When the magnetic sensors S _{1 to} S _{7 that} are in contact with the inspection object 100 via the container W are measured, the magnetic force of the magnetic metal foreign matter contained in the inspection object 100 is measured. When the measurement of the magnetic force for the entire required range in the height direction of the container W is completed, the reciprocating unit 15 descends, the container W is withdrawn from the opening 60 of the magnetic shield box 25, and the recesses 65 and 66 of the table 10 (FIG. Return to 1). In a state where the container W has returned to the recesses 65 and 66, the table 10 rotates 45 ° each time the container W is received from the upstream portion A of the belt conveyor 4, and the container W that has retreated from the magnetic force detection unit 23 is removed from the belt conveyor. 4 can be placed on the downstream portion B. In the illustrated magnetic shield box 25, the container W is prevented from dropping from the reciprocating operation unit 15 by the inner cylinder 61 made of aluminum or synthetic resin attached inside the opening 60. Further, a plate-like member 68 capable of horizontally sliding the bottom of the container W exists between the belt conveyor 4 and the reciprocating unit 15.

Magnetic sensor S ₈ in a magnetic shielding box 25, than any of the magnetic sensors S ₁ -S _7, the container has entered the magnetic shield box 25 W, more specifically the inspection object 100 that is filled in a container W Is used as a reference sensor for detecting magnetic noise inside the magnetic shield box 25. The magnetic force from the inspection object 100 is hardly detected. In the present invention, the types of the magnetic sensors S _{1 to} S ₈ are not specified, and those commonly used in the technical field, such as flux gate sensors, MI sensors, SQUID magnetic sensors, and the like can be used. . However, among them, the fluxgate sensor is particularly excellent in terms of ease of handling.

  The magnetic shield box 25 in the magnetic force detection unit 23 has a container W, in other words, an entrance for entering the individually inspected object 100 and an outlet for exiting the inspected object 100 separately. Rather than preparing, one opening 60 is made to serve as both an inlet and an outlet. On the other hand, the container W is located on the side of the belt conveyor 4 by changing from the state in the upstream side portion A that has been linearly moved in the machine direction MD to the state in which the container W is vertically moved up and down, and the belt conveyor. The magnetic shield box 25 (see FIG. 4) positioned above 4 can enter and leave the opening 60. Therefore, in the magnetic shield box 25, the number and area of the openings can be reduced as compared with the conventional magnetic shield box. In the detection apparatus 1, environmental noise outside the magnetic shield box 25 is affected by the magnetic shield. It is possible to prevent the occurrence of the problem of entering the box 25 and reducing the detection accuracy of the magnetic force of the magnetic metal foreign matter.

  6 and 7 are block diagrams in the detection apparatus 1. In FIG. 6, the general control unit 26 in the apparatus main body 2 includes a control unit 27, a signal processing unit 28, and a quality determination unit 33.

  The control means 27 reads the setting conditions of the operation restricting unit 6, the transporting operation unit 8, and the reciprocating operation mechanism 13, and controls each operation.

For each of the magnetic sensors S _{1 to} S ₇ , the signal processing unit 28 processes the magnetic force detection signal from the magnetic force detection unit 23 based on a predetermined processing condition, and then converts the analog signal into a digital signal. The processed signal is output by processing in the device 31 (see FIG. 7). Specifically, as shown in FIG. 7, the signal processing unit 28 amplifies the magnetic force detection signal from the magnetic force detection unit 23, and the amplified signal is converted into a high pass filter (HPF) and a low pass filter (LPF). An analog filter 30 to be processed, an A / D converter 31 for digitally converting the filtered signal, and an arithmetic processing unit 32 which is a first difference calculating means in the present invention are provided. The arithmetic processing unit 32, and the processed signal on the inspection object 100 that is digitally converted, digitally converted obtained by processing based on a magnetic force detection signal a predetermined process conditions for noise from the reference sensor S ₈ The difference calculation is performed with respect to the processed signal for noise. The arithmetic processing unit 32 also includes an absolute value conversion circuit that calculates the absolute value of the difference obtained by the difference calculation, and a sum circuit that calculates the sum of the absolute values.

  The pass / fail determination means 33 determines whether or not magnetic metal foreign matter is mixed in the inspection object 100. The sum of the absolute values of the differences obtained by the arithmetic processing unit 32 is a threshold 34 (see FIG. 6). ) Is judged as defective, and those not exceeding are judged as good. The level of the threshold 34 can be changed as appropriate by using the setting means 36 (see FIG. 6) built in the operation panel 3.

  The determination result in the pass / fail determination means 33 is output to the display unit 35 (see FIG. 1), and displays the voltage of the signal for the container W determined to be defective, the number of defective products, the time when the defective product was detected, and the like. can do. The determination result is output by the control means 27 to the sorting unit 50 attached to the downstream portion B of the belt conveyor 4. When the photoelectric sensor 51 (see FIG. 1) detects a defective container W, the sorting unit 50 operates a rod 52 (see FIG. 1) for pushing the container W out of the belt conveyor 4.

  The display unit 35 in the apparatus main body 2 includes a display device such as a liquid crystal display as shown in FIG. The display unit 35 also serves as a touch panel that can input operating conditions of the detection device 1.

  The storage means 37 is composed of a memory built in the liquid crystal display used in the display unit 35 and a storage medium from the CF card, and can store data such as processed signals and pass / fail judgment results.

FIG. 8 shows an example of the driving operation unit 38 (see FIG. 6) formed on the operation panel 3 (see FIG. 1). When the power is turned on with the power switch 40 in the operation operation unit 38, the power lamp 39 is turned on. When the power is turned off with the power switch 40, the power lamp 39 is turned off. The manual / automatic switch 41 can select a manual operation mode and an automatic operation mode. When the start button 42 is pressed in the automatic operation mode, a series of inspection processes starts. When the stop button 43 is pressed in the automatic operation mode, the inspection process is stopped. When the reset button 44 is pressed and held in the automatic operation mode, the production number and the disposal number on the screen of the display unit 35 are reset. When the manual button 45 is pressed in the manual operation mode, the table 10 can be manually rotated by 45 °. When the emergency stop button 46 is pressed, the belt conveyor 4 stops. The changeover switch 47 can select a normal inspection for the container W and a sensor inspection for the sensors S _{1 to} S ₈ . When the sensor inspection is selected and the dial 48 is turned in order, it is possible to sequentially check whether or not the magnetic sensors S _{1 to} S ₈ are operating normally on the screen of the display unit 35.

  The alarm oscillator 49 (see FIGS. 6 and 8) is lit in green when the series of inspection processes is in a normal state and the state in which the container W is determined to be non-defective continues. When the pass / fail determination means 33 determines that the container W is a defective product, it is lit red to notify the operator of the occurrence of the defective product.

Figure 9 is a IX-IX view taken along line of FIG. 5, the magnetic sensor _S 1 -S _7, the foundation 70 for the magnetic sensors _S 1 -S ₇ is mounted, showing only the inner cylinder 61 Yes. The container W is indicated by a virtual line. An operation checking coil C ₁ -C ₇ is attached to each of the magnetic sensors S ₁ -S ₇ arranged in the circumferential direction of the container W. Although not shown, the magnetic sensor S ₈ operation check coil C ₈ to _(see FIG. 5) is attached. When sensor inspection is selected with the changeover switch 47 (see FIG. 8) and the dial 48 is turned to select the magnetic sensors S _{1 to} S ₈ in order, a pulse current sequentially flows through the operation check coils C _{1 to} C ₈ . When the pulse current flows, sequentially weak magnetic field is generated in the vicinity of the magnetic sensor S ₁ -S _8, each of the magnetic sensors S ₁ -S _8, depending on whether detect the weak magnetic field, normally It is determined whether it is operating.

  The present invention is not limited to the illustrated embodiment. For example, the shape and material of the container W can be changed to an appropriate shape and material as long as there is no hindrance to the detection of the magnetic metal foreign matter. The operation restricting portion 6 can replace the swing type stopper 6b in the illustrated example with a stopper that reciprocates in the crossing direction or the vertical direction. The rotating table 10 of the transport operation unit 8 can be replaced with one that reciprocates between the belt conveyor 4 and either the reciprocation operation unit 15 or the magnetic shield box 25 in the crossing direction. The reciprocating unit 15 may also allow the container W to enter and leave the magnetic shield box 25 by reciprocating in the crossing direction. In such a case, the magnetic shield box 25 is not opened in the vertical direction as in the illustrated example, but used in the horizontal direction, that is, in the intersecting direction. In the present invention, the reciprocating mechanism 13 may raise and lower the magnetic shield box 25 so that the stationary container W enters and leaves the opening 60.

  In the present invention, the number and arrangement of magnetic sensors for detecting magnetism from a magnetic metal foreign material are not limited to the illustrated example, and can be determined as appropriate according to the state of the inspection object 100 and / or the container W. For example, in FIG. 5, at least two substrates 70 can be set in the vertical direction, and a magnetic sensor can be attached to each substrate 70.

Further, the present invention does not particularly limit the method for measuring the magnetic force of the magnetic metal foreign matter contained in the inspection object 100. The measurement method illustrated in FIGS. 4-9 is merely an example. For example, in the present invention, the first difference calculation means (calculation processing unit 32, see FIG. 7) is used to detect the magnetic force of each of the magnetic sensors S _{1 to} S ₇ and the magnetic noise in the magnetic shield box 25. It performs difference calculation for obtaining the difference between the force of the sensor S _8, instead of being determined that the magnetic metal foreign object is present if the sum of the absolute value of the difference exceeds a preset threshold value , a portion of the magnetic force of the difference calculated by the calculated difference (the primary difference) of the difference calculation for obtaining the difference (second-order difference) of a portion of the magnetic force of the reference sensor S ₈ repetitions, i.e. n-order difference and the reference sensor S ₈ After obtaining the (n + 1) th order difference that is the difference between and the absolute value of the difference and the sum of the absolute values, the noise component is derived from the magnetic force output by each of the magnetic sensors S ₁ -S _7. Erased or low While for, by amplifying the signal component of a magnetic metal foreign object can be detected magnetic metal foreign object accurately.

Further, without using the first difference calculation means and the reference sensor S _8, make a pair of each other magnetic sensor between the magnetic sensor S ₁ -S ₇ in FIG. 9, for example, the arithmetic processing unit 32 (see FIG. 7) The difference calculation means (second difference calculation means) for calculating the difference between the pair is used to calculate the difference between the magnetic sensors, and is included in the output signal of each magnetic sensor. It is also possible to obtain a difference between states in which noise has been eliminated or reduced, and to detect a magnetic metal foreign object signal from the sum of absolute values of the differences. When making a pair of magnetic sensors, a pair of adjacent magnetic sensors, for example, a pair of the magnetic sensor S ₁ and the magnetic sensor S ₂ can be formed. However, in order to improve detection accuracy, for example, the magnetic sensor S ₁ As for, it is preferable to make a pair with any of the other magnetic sensors S ₃ , S ₄ , S ₅ while avoiding the adjacent magnetic sensor S ₂ .

The first invention according to the detection device of the present invention described so far can be summarized as follows.
A detector for detecting magnetic metal foreign matter contained in each of the inspection objects by sequentially measuring the magnetic force of the inspection object while moving a plurality of individually prepared inspection objects in one direction. ,
The detection device includes a magnetic shield box having a bottom portion, a ceiling portion, and a side wall portion connected to both of them to form a magnetic shield space, and the magnetic metal foreign matter installed inside the magnetic shield box. A plurality of magnetic sensors for measuring the magnetic force of the magnetic signal, signal processing means for detecting the magnetic force of the magnetic metal foreign matter based on an output signal of the magnetic sensor, and a reciprocating mechanism,
The magnetic shield box is formed with one opening that serves both as an entrance for allowing the inspection object to enter the magnetic shield space and as an exit for exiting the inspection object.
The reciprocating mechanism can cause the inspected object to reciprocate to enter and leave the opening of the inspected object,
In the magnetic shield box, the magnetic sensor is installed at a position facing the inspection object that has entered the opening.
Moreover, the 2nd invention which concerns on the detection apparatus of this invention can be put together as follows at least.
The detection device includes a magnetic shield box having a bottom portion, a ceiling portion, and a side wall portion connected to both of them to form a magnetic shield space, and the magnetic metal foreign matter installed inside the magnetic shield box. A plurality of magnetic sensors for measuring the magnetic force of the magnetic signal, signal processing means for detecting the magnetic force of the magnetic metal foreign matter based on an output signal of the magnetic sensor, and a reciprocating mechanism, the magnetic shield box, One opening is formed to serve as both an entrance for allowing the inspection object to enter the magnetic shield space and an exit for exiting the inspection object, and the reciprocating mechanism causes the magnetic shield box to reciprocate to move the object. The inspection object can enter and exit the opening, and the magnetic sensor enters the opening in the magnetic shield box. Wherein is installed at a position opposite to the object to be inspected was.

The present invention relating to a magnetic metal foreign object detection device includes at least the following embodiments.
(1) The reciprocating mechanism includes a reciprocating unit that causes the inspection object to perform the reciprocating motion, and the detection device includes conveying means for sequentially conveying the individual inspection objects in one direction; It is interposed between the transport means and the reciprocating part, and transports the inspection object located on the transport means to the reciprocating part while transporting the inspection object located on the reciprocating part. And a transporting motion part for transporting to the means.
(2) The conveyor is a conveyor that travels horizontally in the one direction, the magnetic shield box is located above the conveyor, and the opening is formed in a lower portion of the magnetic shield box, The transporting operation unit reciprocates or rotates between the conveyor and the reciprocating operation unit, and the reciprocating operation unit reciprocates linearly in the vertical direction of the magnetic shield box.
(3) The electric actuator that drives the reciprocating unit is covered with the magnetic shield.
(4) The electric actuator that drives the carrying operation unit is covered with a magnetic shield.
(5) The object to be inspected is placed in a container, and the plurality of magnetic sensors are arranged on a horizontal plane, are outside in the radial direction of the container, and the circumferential direction of the container Are arranged at intervals.
(6) In the magnetic shield box, in addition to the plurality of magnetic sensors arranged at intervals in the circumferential direction, the shortest distance to the inspection object in the magnetic shield box Is disposed at a position farther than the shortest distance of each of the plurality of magnetic sensors, and a reference sensor for measuring magnetic noise in the inside of the magnetic shield box is installed, and the signal processing means outputs an output signal of each of the plurality of magnetic sensors. And first difference calculating means for calculating a difference between the output signal of the reference sensor and the reference sensor.
(7) The signal processing means includes second difference calculation means for forming a pair between the plurality of magnetic sensors and calculating a difference between the output signals of the paired magnetic sensors.

The invention according to the detection method of the present invention described so far can be summarized at least as follows.
The present invention is characterized in that a magnetic metal foreign object contained in a plurality of inspection objects is detected using the magnetic metal foreign object detection device according to the present invention.
The present invention relating to the detection method includes the following embodiments.
(1) The object to be inspected is a food in a container.

1 Device 4 Conveying means (belt conveyor)
DESCRIPTION OF SYMBOLS 8 Conveyance operation part 11 Actuator 12 Magnetic shield 13 Reciprocation mechanism 15 Reciprocation action part 16 Actuator 17 Magnetic shield 25 Magnetic shield box 28 Signal processing means (signal processing part)
32 Arithmetic processing means (arithmetic processing unit)
60 opening 100 inspection object S ₁ -S ₇ magnetic sensor S ₈ reference sensor (magnetic sensor)
W container

Claims (11)

A detector for detecting magnetic metal foreign matter contained in each of the inspection objects by sequentially measuring the magnetic force of the inspection object while moving a plurality of individually prepared inspection objects in one direction. ,
The detection device includes a magnetic shield box having a bottom portion, a ceiling portion, and a side wall portion connected to both of them to form a magnetic shield space, and the magnetic metal foreign matter installed inside the magnetic shield box. A plurality of magnetic sensors for measuring the magnetic force of the magnetic signal, signal processing means for detecting the magnetic force of the magnetic metal foreign matter based on an output signal of the magnetic sensor, and a reciprocating mechanism,
The magnetic shield box is formed with one opening that serves both as an entrance for allowing the inspection object to enter the magnetic shield space and as an exit for exiting the inspection object.
The reciprocating mechanism can cause the inspected object to reciprocate to enter and leave the opening of the inspected object,
In the magnetic shield box, the magnetic sensor is installed at a position facing the inspection object that has entered the opening. A detector for detecting magnetic metal foreign matter contained in each of the inspection objects by sequentially measuring the magnetic force of the inspection object while moving a plurality of individually prepared inspection objects in one direction. ,
The detection device includes a magnetic shield box having a bottom portion, a ceiling portion, and a side wall portion connected to both of them to form a magnetic shield space, and the magnetic metal foreign matter installed inside the magnetic shield box. A plurality of magnetic sensors for measuring the magnetic force of the magnetic signal, signal processing means for detecting the magnetic force of the magnetic metal foreign matter based on an output signal of the magnetic sensor, and a reciprocating mechanism,
The magnetic shield box is formed with one opening that serves both as an entrance for allowing the inspection object to enter the magnetic shield space and as an exit for exiting the inspection object.
The reciprocating mechanism can cause the magnetic shield box to reciprocate to enter and exit the opening of the inspection object,
In the magnetic shield box, the magnetic sensor is installed at a position facing the inspection object that has entered the opening.   The reciprocating mechanism includes a reciprocating unit that causes the inspection object to reciprocate, and the detection device includes a conveying unit that sequentially conveys the individual inspection objects in one direction, and the conveying unit. And the reciprocating unit between the reciprocating unit and the reciprocating unit, the inspection unit positioned between the reciprocating unit and the reciprocating unit. The detection device according to claim 1, further comprising a carrying operation unit for carrying. The transport means is a conveyor that travels horizontally in the one direction, the magnetic shield box is located above the conveyor, and the opening is formed in a lower portion of the magnetic shield box, and the transport operation unit 4. The detection device according to claim 3 , wherein the reciprocating motion or the reciprocating motion is performed between the conveyor and the reciprocating motion portion, and the reciprocating motion portion reciprocates linearly in the vertical direction of the magnetic shield box. . The electric actuator for driving the reciprocating operation part detecting apparatus according to claim 3 or 4, wherein is covered with magnetic shielding. The detection device according to claim 3 , wherein the electric actuator that drives the transporting operation unit is covered with a magnetic shield. The inspection object is placed in a container, and a plurality of the magnetic sensors are arranged on a horizontal plane, are outside in the radial direction of the container, and are spaced apart in the circumferential direction of the container. The detection device according to claim 1, wherein the detection device is arranged open. Inside the magnetic shield box, in addition to the plurality of magnetic sensors arranged at intervals in the circumferential direction, in the magnetic shield box, the shortest distance to the object to be inspected is a plurality of A reference sensor that is located farther than the shortest distance of each of the magnetic sensors and that measures magnetic noise inside the magnetic shield box is installed, and the signal processing means is configured to output an output signal of each of the plurality of magnetic sensors and the reference sensor. The detection apparatus according to claim 1, further comprising first difference calculation means for calculating a difference from the output signal. It said signal processing means, the claims includes a second difference calculating means for calculating a plurality of said make pairs between the magnetic sensors, the difference between the output signal each other of the magnetic sensor in the pair 1,3 8. The detection device according to any one of 7 above. Detection method characterized by detecting the magnetic metal foreign matter contained in the plurality of object to be inspected using the detecting apparatus according to any one of claims 1-9. The detection method according to claim 10 , wherein the inspection object is a food contained in a container.

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