JP2017096821A - Appearance inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an appearance inspection device which is capable of obtaining excellent performance in both of inspection accuracy and inspection efficiency, excellent in versatility, and capable of achieving miniaturization or the like.SOLUTION: The appearance inspection device includes an imaging apparatus 66 having a fisheye lens, rotates a tablet 5 along an arc-shaped or circular conveyance path centering on the optical axis of the fisheye lens, and sequentially conveys the tablet 5 to a plurality of imaging positions P1 to P6, while changing a part located on an optical axis side in the side surface of the tablet 5. Whenever the tablet 5 is arranged in the imaging positions P1 to P6, the imaging apparatus 66 images at least the side surface of the tablet 5, to acquire the image data of the full circumference of the side surface. The quality of the tablet 5 is determined on the basis of the acquired image data.SELECTED DRAWING: Figure 8

Description

  The present invention relates to an appearance inspection apparatus for inspecting an inspection object such as a tablet.

  The appearance inspection apparatus inspects the appearance of an object to be inspected such as a tablet. For example, the appearance inspecting apparatus inspects for an abnormality in the shape of the object to be inspected due to chipping or the like, or adhesion of foreign matters to the inspected object.

  Here, the appearance inspection apparatus for inspecting the side surface of the inspection object has a convex lens whose focal point converges at the front end of the lens, the convex lens faces the front or back surface of the circular tablet as the inspection object, and the focal point. There has been proposed one provided with imaging means configured such that circular tablets are arranged within a distance (see, for example, Patent Document 1). According to the appearance inspection apparatus, it is possible to obtain image data in which the front surface or back surface of the circular tablet and the entire circumference of the side surface are represented in a plane, and to perform a quick inspection.

  In addition, another visual inspection apparatus for inspecting the side surface of the inspection object includes a supply drum having a large number of rotatable receiving cylinders on the outer periphery while adsorbing the inspection object, and a range surrounded by a light source box. And a plurality of (three or more) objects to be inspected are known (for example, see Patent Document 2). In the appearance inspection apparatus, the object to be inspected is conveyed by the rotation of the supply drum, and the object to be inspected is rotated one or more times by the rotation of the receiving cylinder within the range surrounded by the light source box (in the field of view of the imaging means). Then, at least three locations on the side surface of each inspection object are imaged by the imaging means. Thereby, it is supposed that the whole circumference of the side surface of the object to be inspected can be inspected reliably.

JP 2004-241488 A Japanese Examined Patent Publication No. 2-644

  However, in the former appearance inspection apparatus, if the inspection object is arranged in a state where the central axis is deviated from the optical axis of the convex lens, the inspection object TA (image data in the image data ID) as shown in FIG. Deformation (distortion) occurs in the portion corresponding to the inspection object TA in the ID, and in particular, the width of the side surface of the inspection object TA (the part with the dotted pattern in FIG. A) changes. This phenomenon will be briefly described. As shown in FIG. 16, when the center axis CL2 of the inspection object TA is shifted from the optical axis CL1 of the convex lens LE, in the image sensor IS, the side surface of the inspection object TA is changed. Among them, the number of light receiving elements LR that receive light from the side close to the optical axis CL1 is relatively small, and the number of light receiving elements LR that receive light from the side far from the optical axis CL1 is relatively large. As a result, as described above, the inspection object is deformed (distorted) in the image data. Note that FIG. 16 shows an optical path and the like until light from the side surface of the inspection object TA is received by the image sensor IS when an image side telecentric lens is used as the convex lens LE.

  If the inspection object in the image data is deformed as described above, the degree of appearance abnormality (for example, the size of the foreign matter) cannot be accurately grasped from the image data. For this reason, there is a risk that the inspection accuracy may be lowered. On the other hand, it is also conceivable that the position of the inspection object is corrected so that the central axis of the inspection object coincides with the optical axis of the convex lens. However, in this case, there is a possibility that the inspection efficiency is lowered by the amount of correction of the position of the inspection object. As a result, in the former appearance inspection apparatus, inspection accuracy and inspection efficiency are in a trade-off relationship, and it is difficult to obtain good performance in both cases.

  In addition, when the object to be inspected is not a circular tablet (for example, in the case of an irregular tablet or capsule), the optical axis from each part of the object to be inspected even if the optical axis of the convex lens coincides with the central axis of the object to be inspected. The inspection object in the image data is deformed according to the distance up to. Therefore, the former appearance inspection apparatus is limited to a disk-shaped object such as a circular tablet, and the inspectable object is inferior in versatility.

  On the other hand, in the latter appearance inspection apparatus, the object to be inspected is imaged a plurality of times by a single imaging means, so the relative position of the inspection object with respect to the imaging means is different at each imaging. For example, imaging is performed in a state where the inspection object exists in front of the imaging means (lens), or imaging is performed in a state where the inspection object is displaced from the front of the imaging means (lens). Then, with the difference in the position of the inspection object, the incident angle of the light from the inspection object to the imaging unit changes, so that a difference occurs in the size of the inspection object or attached foreign matter in the image data. There is a fear. As a result, there is a concern that the inspection accuracy becomes insufficient.

  In contrast to this, by preparing a plurality of imaging means and in each imaging means, imaging is performed when the relative position of the inspection object with respect to itself becomes a fixed position, respectively, the inspection object in the image data It is conceivable to prevent a difference in the size of each other. However, in this case, since a plurality of imaging means are required, there is a possibility that the apparatus becomes large and complicated, and the cost increases.

  The present invention has been made in view of the above circumstances, and its purpose is to obtain good performance in both inspection accuracy and inspection efficiency, and to have excellent versatility and downsizing. An object of the present invention is to provide an appearance inspection apparatus capable of

  In the following, each means suitable for solving the above-described object will be described in terms of items. In addition, the effect specific to the means to respond | corresponds as needed is added.

Means 1. Conveying means for conveying a predetermined object to be inspected;
Imaging means for imaging the inspection object conveyed by the conveying means from above via a lens;
A visual inspection apparatus comprising: a determination unit that determines the quality of the inspection object based on the image data acquired by the imaging unit;
The lens is a fisheye lens;
The transport means rotates a part to be inspected along a circular or circular transport path centered on the optical axis of the fisheye lens to locate a part positioned on the optical axis side of the side surface of the test object. While changing, sequentially convey the inspection object to a plurality of imaging positions,
The imaging means is configured to acquire image data for the entire circumference of the side surface by imaging at least the side surface of the inspection object every time the inspection object is arranged at the imaging position. An appearance inspection apparatus characterized by comprising:

  According to the means 1, image data for the entire circumference of the side surface can be obtained via the fisheye lens. Here, when a fish-eye lens is used, it is possible to focus to infinity at a location away from the lens by a predetermined position or more. Therefore, according to the means 1, it is possible to focus on both a portion of the inspection object that is relatively close to the lens and a portion of the inspection object that is relatively far from the lens. As a result, it is possible to obtain image data in which the object to be inspected and foreign matters attached thereto are clearly represented. Note that “in focus” includes not only the case where the object is strictly in focus but also the case where the object is almost in focus so that the inspected object is not blurred in the image data.

  Further, according to the means 1, the object to be inspected is imaged while being conveyed along an arcuate or circular conveyance path centered on the optical axis of the lens. Therefore, without specially correcting the position of the inspection object, the distance from the lens to the inspection object and the incident angle of light from the inspection object with respect to the lens can be made substantially the same at each imaging position. As a result, in the obtained image data, it is possible to more reliably prevent deformation (distortion) of the object to be inspected or foreign matter, or variations in the size of the object to be inspected. .

  As described above, according to the above-described means 1, the position of the inspection object is specially corrected using image data in which the inspection object or the like is clearly displayed and the inspection object or the like has almost no deformation or variation in size. It is possible to obtain the entire circumference of the side surface without performing it, that is, without causing a decrease in inspection efficiency. Therefore, the entire circumference of the side surface can be inspected accurately and quickly, and very good performance can be obtained in both inspection accuracy and inspection efficiency.

  Further, according to the above means 1, the object to be inspected is other than a round tablet such as atypical tablets and capsules, a circular tablet having a hole in the center, or the difference in tablet diameter, capsule number, etc. Accordingly, even if the sizes are different, it is possible to focus on each part of the inspection object during imaging, and as a result, image data in which the inspection object or the like is clearly displayed can be obtained. Therefore, various types of inspection objects can be inspected, and excellent versatility can be obtained.

  Further, only one imaging means is sufficient for obtaining the above-described effects. Therefore, the appearance inspection apparatus can be reduced in size and simplified, and the cost can be reduced.

Mean 2. The conveying means is
A rotation means for changing the portion of the side surface located on the optical axis side by rotation of the placement portion, and a placement portion on which the inspection object is placed;
The appearance inspection apparatus according to claim 1, further comprising: a revolving unit that moves the placement portion about the optical axis along the conveyance path.

  According to the above means 2, the object to be inspected can be sequentially conveyed to a plurality of imaging positions by the revolving means while the part located on the optical axis side on the side surface of the object to be inspected is changed by the rotation means. Therefore, the conveying means can be realized with a relatively simple configuration, and the appearance inspection apparatus can be reduced in size and simplified, and the cost can be reduced more effectively.

Means 3. The object to be inspected has a circular outer shape in a plan view,
The imaging means obtains data for an inspection range, which is a range smaller than a half circumference along a circumferential direction of the side surface, centered on a portion facing the optical axis in the inspection object, for the entire circumference of the side surface. So that the inspection object is imaged,
3. The appearance inspection apparatus according to claim 1, wherein the determination unit is configured to determine whether the inspection object is good based on the data of the inspection range in the image data.

  In the image data, portions located on both sides in the circumferential direction of the side surface of the inspection object appear as having a smaller area than a portion located at the center of the side surface. Therefore, for example, when a foreign substance adheres to this portion, the foreign substance appears in a relatively small size in the image data, and there is a possibility that what should be detected as a foreign substance cannot be detected. On the other hand, for example, it is conceivable to increase the inspection accuracy by making the inspection conditions different in each part of the image data, such as making the detection accuracy of foreign matters different in each part of the side surface. In some cases, the processing burden may increase.

  In this regard, according to the above means 3, the imaging means performs at least three imagings, thereby side-viewing data of an inspection range that is a range less than a half circumference centered on a portion facing the optical axis in the inspection object. The determination means performs an inspection based on the data of the inspection range in the image data. Therefore, it is possible to perform inspection by excluding the portions of the image data located on both ends in the circumferential direction of the side surface from the inspection target. Thereby, the inspection object can be inspected under the same inspection conditions. As a result, it is possible to maintain good inspection accuracy while reducing the processing load.

  In addition, the inspection accuracy can be improved as the inspection range is smaller. Therefore, it is more preferable to set the inspection range to a range equal to or less than ¼ circumference along the circumferential direction of the side surface, and to a range equal to or less than 1/6 circumference along the circumferential direction of the side surface. Even more preferred.

Means 4. The image processing means for extracting data corresponding to the inspection range in a plurality of the image data, and creating connected image data in which each extracted data is continuous for the entire circumference of the side surface,
4. The appearance inspection apparatus according to claim 3, wherein the determination means is configured to determine the quality of the inspection object based on the connected image data.

  According to the means 4, the entire circumference of the side surface can be inspected based on one connected image data. Therefore, the entire circumference of the side surface can be easily inspected under the same inspection conditions, and the processing load can be further reduced while maintaining good inspection accuracy.

  According to the means 3, the size of the inspection object in each image data can be made almost constant. Therefore, it is possible to easily create linked image data.

Means 5. The inspection object has a front surface and a back surface that sandwich the side surface,
The imaging means images at least one of the front surface and the back surface together with the side surface,
The determination means is further configured to determine pass / fail of the inspection object based on data of the at least one surface imaged by the imaging means in the image data. The appearance inspection apparatus according to any one of 1 to 4.

  According to the means 5, not only the side surface of the inspection object but also the front surface or the back surface of the inspection object can be inspected. Accordingly, it is not necessary to separately inspect the front and back surfaces, and the time required for the inspection can be shortened.

  In addition, since a fisheye lens is used, in the image data, the front and back surfaces of the inspection object appear in a clear state as well as the side surface of the inspection object. Therefore, it is possible to accurately inspect the front and back surfaces of the inspection object.

Means 6. The inspection object has a front surface and a back surface that sandwich the side surface,
The imaging means is configured to acquire image data for the entire circumference of the side surface in both a state where the front and back of the inspection object are not reversed and a state where the surface is reversed. The appearance inspection apparatus according to any one of means 1 to 5.

  According to the means 6, the inspection can be performed based on the image data in both the state where the front and back surfaces of the previous inspection object are not reversed and the state where the front and back are reversed. Thereby, it is possible to eliminate the influence on the inspection due to the difference in the direction of the inspection object (whether or not the inspection object is reversed), and the inspection accuracy can be further improved.

Means 7. The transport means transports a plurality of objects to be inspected at a time so that the objects to be inspected are arranged at the respective imaging positions,
The appearance inspection apparatus according to any one of means 1 to 6, wherein the imaging means is configured to image a plurality of the inspection objects arranged at the respective imaging positions at a time.

  According to the means 7, image data relating to a plurality of inspection objects can be obtained at a time. As a result, the inspection efficiency can be further improved.

It is a perspective view of a PTP sheet. It is an expanded sectional view of a PTP sheet. It is a perspective view of a PTP film. It is a schematic diagram which shows schematic structure of a PTP packaging machine. It is a block diagram which shows the structure of an external appearance inspection apparatus. It is a perspective schematic diagram of an imaging unit. It is a front schematic diagram of an imaging unit. It is a plane schematic diagram of an imaging unit. It is explanatory drawing for demonstrating the focus position etc. which can be in a fisheye lens. It is explanatory drawing which shows the arrangement | positioning state of the tablet in image data. It is a plane schematic diagram for demonstrating the change of the position and direction of a tablet when a mounting part rotates and revolves. It is a flowchart of an inspection process. It is explanatory drawing for demonstrating the flow etc. of the image process in an inspection process. It is explanatory drawing for demonstrating the setting reason of a test | inspection range. It is explanatory drawing for demonstrating the subject in a prior art. It is explanatory drawing for demonstrating the subject in a prior art.

  Hereinafter, an embodiment will be described with reference to the drawings. First, the PTP sheet obtained by the PTP packaging machine of this embodiment will be described. As shown in FIGS. 1 and 2, the PTP sheet 1 in the present embodiment includes a container film 3 having a plurality of pocket portions 2 and a cover film attached to the container film 3 so as to close the pocket portions 2. 4.

  The container film 3 is made of, for example, a transparent or translucent thermoplastic resin material that is relatively hard and has a predetermined rigidity, such as PP (polypropylene) or PVC (polyvinyl chloride). The cover film 4 is made of an opaque material (for example, an aluminum foil or the like) having a sealant made of, for example, a polyester resin applied on the surface.

  Each pocket 2 stores one tablet 5 as an object to be inspected. In the present embodiment, the tablet 5 has a circular disk shape in plan view having a predetermined diameter (for example, 8 mm), and includes a side surface 5A, and a flat surface 5B and a back surface 5C sandwiching the side surface 5A. It has a configuration.

  Further, the container film 3 of the PTP sheet 1 is formed with a plurality of horizontal slits 6 so as to be separated into, for example, a pair of small pieces including two pocket portions 2 (of course, vertical slits are formed. Or the slit may be omitted).

  In addition, the PTP sheet 1 is manufactured into a sheet shape by punching a strip-shaped PTP film 7 (see FIG. 3) formed from the strip-shaped container film 3 and the cover film 4.

  Next, the structure of the PTP packaging machine (blister packaging machine) 10 for manufacturing the PTP sheet 1 will be described.

  As shown in FIG. 4, on the most upstream side of the PTP packaging machine 10, the strip-shaped container film 3 is wound in a roll shape. The container film 3 wound in a roll shape is intermittently conveyed, and a heating device 12 and a pocket portion forming device 13 are arranged in parallel along the conveyance path of the container film 3. Yes. And in the state which the container film 3 was partially heated by the heating apparatus 12 and this container film 3 became comparatively flexible, the pocket part 2 is formed in the container film 3 by the pocket part formation apparatus 13. FIG. Formation of this pocket part 2 is performed at the interval between conveyance operations of the container film 3.

  A tablet supply device 15, a filling device 16, an inspection device 17, a sealing device 18, and the like are disposed along the conveyance path of the container film 3 in which the pocket portion 2 is formed.

  The tablet supply device 15 includes a hopper (not shown) for storing a large amount of tablets 5, an appearance inspection device 50 for inspecting the appearance of the tablets 5, and a feeder for sending the tablets 5 from the hopper to the appearance inspection device 50 ( For example, a ball feeder) and a spring chute (not shown) for supplying the tablet 5 from the appearance inspection device 50 to the filling device 16 are provided. In the tablet supply device 15, after the quality of the tablet 5 is determined by the appearance inspection device 50, the non-defective tablet 5 is sequentially supplied to the filling device 16. Details of the appearance inspection apparatus 50 will be described later.

  The filling device 16 includes a rotary drum or the like, and automatically fills the tablet 5 into the pocket portion 2 of the container film 3 to be conveyed.

  The inspection device 17 is for inspecting whether or not the tablets 5 are reliably filled in the pockets 2, whether or not there are abnormal appearances such as chipping and cracking of the tablets 5, and the presence or absence of foreign matter. . The inspection device 17 performs an inspection from the opening side of the pocket portion 2.

  On the other hand, the cover film 4 formed in a belt shape is wound in a roll shape on the most upstream side. The drawing end of the cover film 4 wound in a roll shape is guided toward the sealing device 18.

  The sealing device 18 includes a film receiving roll 19 and a heating roll 20, and the heating roll 20 can be pressed against the film receiving roll 19. And container film 3 and cover film 4 are sent between both rolls 19 and 20, and container film 3 and cover film 4 pass between both rolls 19 and 20 in the state of heating pressure contact, A cover film 4 is adhered to the container film 3, whereby a band-shaped PTP film 7 in which the tablet 5 is filled in each pocket portion 2 is manufactured.

  An inspection device 23 for detecting an abnormality of the tablet 5 or the like from the pocket portion 2 side is provided downstream of the sealing device 18. In addition, when a defective product is determined by the inspection devices 17 and 23, a defective product signal is sent to a defective sheet discharge mechanism (not shown), and the PTP sheet 1 that has been determined to be defective is separately discharged by the defective sheet discharge mechanism. It has become so.

  A slit forming device 24 and a sheet punching device 26 are sequentially arranged along the transport path of the PTP film 7 downstream of the inspection device 23. The slit forming device 24 has a function of forming the horizontal slit 6 at a predetermined position of the PTP film 7. The sheet punching device 26 has a function of punching the PTP film 7 into one PTP sheet.

  The PTP sheet 1 punched by the sheet punching device 26 is conveyed by a take-out conveyor 27 and temporarily stored in a finished product hopper 28.

  Further, a cutting device 29 is disposed on the downstream side of the sheet punching device 26. The cutting device 29 has a function of cutting the remaining material portion remaining after punching by the sheet punching device 26 into a predetermined dimension. The remaining material portion (scrap portion) cut by the cutting device 29 is stored in the scrap hopper 30 and then discarded separately.

  Such a PTP packaging machine 10 is constructed inside the housing in consideration of hygiene. In the present embodiment, the tablet supply device 15 and the filling device 16 are unitized as a filling unit 40 separate from the device main body 11 by being covered with a predetermined unit cover. The filling unit 40 is detachable from the apparatus main body 11.

  Next, the configuration of the appearance inspection apparatus 50 will be described. As shown in FIG. 5, the appearance inspection apparatus 50 controls the operation of the imaging unit 60 for imaging the tablet 5 and obtaining image data, and the tablet 5 is inspected based on the image data. And a control processing unit 70 for this purpose.

  5 to 8, the imaging unit 60 includes a revolution motor 61, a revolution table 62, a rotation motor 63, a placement portion 64, an illumination device 65, an imaging device 66 as an imaging means, and the like ( 6-8, the illuminating device 65 is not shown). In this embodiment, a revolving means is constituted by the revolving motor 61 and the revolving table 62, and a revolving means is constituted by the revolving motor 63, the placement portion 64, and a revolving drive belt 67 described later. Moreover, a conveyance means is comprised by these rotation means and revolution means.

  The revolution motor 61 is constituted by a predetermined servo motor, and is arranged such that its rotation axis extends in the vertical direction. Moreover, the revolution motor 61 has a built-in predetermined encoder, and can output information (signal) relating to its own rotation amount from the encoder.

  The revolution table 62 has a disk shape, and is connected to the shaft portion of the revolution motor 61 in a state where the center axis of the revolution table 62 is coaxial with the rotation axis of the revolution motor 61. The revolution table 62 is rotated by the rotation of the revolution motor 61.

  The rotation motor 63 is constituted by a predetermined servo motor, and is arranged outside the outer periphery of the revolution table 62 in a state where its own rotation axis is parallel to the rotation axis of the revolution motor 61. Moreover, the autorotation motor 63 has a built-in predetermined encoder, and can output information (signal) related to its own rotation amount from the encoder.

  The mounted portions 64 have a disk shape, and a plurality of placement portions 64 are provided at equal intervals along the rotation direction of the revolution table 62 on the outer peripheral side of the revolution table 62. In addition, the center of the placement portion 64 is parallel to the rotation axis of the revolution motor 61 or the rotation motor 63, and can be freely rotated with respect to the revolution table 62 with its own center axis as the rotation axis. Yes.

  A belt-like rotation driving belt for transmitting the rotation of the rotation motor 63 is provided on the outer peripheral surface of each mounted portion 64 disposed within a range of 180 ° located on the opposite side of the rotation motor 63. There are 67 bridges. Thereby, when the autorotation motor 63 rotates, each placement part 64 positioned within the range of 180 ° rotates about its own central axis. Hereinafter, the rotation of the placement section 64 due to the rotation of the rotation motor 63 may be referred to as “the rotation of the placement section 64”.

  The rotation driving belt 67 is a toothed belt in which a plurality of teeth are formed on the inner periphery so that the rotation of the rotation motor 63 is more reliably transmitted to the placement portion 64. The outer periphery of the placement portion 64 may have a gear shape that can mesh with the rotation driving belt 67.

  Further, the placement section 64 moves along a circular conveyance path centering on the rotation axis of the revolution motor 61 as the revolution table 62 rotates. Hereinafter, the movement of the placement section 64 due to the rotation of the revolution motor 61 may be referred to as “revolution of the placement section 64”. In the present embodiment, each placement portion 64 moves (revolves) in this order with respect to the arrangement position P0, the imaging positions P1 to P6, and the removal position P7 (see FIG. 8) arranged in an arc shape.

  The arrangement position P0 is a position where the tablet 5 is placed on the center of the upper surface of the placement portion 64 by a predetermined placement device (not shown). The tablet 5 is placed in a state where the front surface 5B or the back surface 5C is an upper surface.

  The imaging positions P1 to P6 are positions at which imaging of the tablet 5 placed on the placement part 64 is performed.

  The removal position P7 is a position at which the tablet 5 placed on the placement portion 64 is picked up by a predetermined pickup device (not shown). The picked-up tablet 5 is usually transferred to the downstream side (the spring chute side). However, the tablet 5 determined to be defective is transferred to a predetermined defective product storage hopper (not shown).

  The illumination device 65 is installed above the imaging positions P1 to P7 and irradiates the tablet 5 placed on the placement portion 64 with predetermined light (for example, near infrared light or visible light).

  The imaging device 66 includes a camera (for example, a CCD camera or a CMOS camera) having sensitivity in the wavelength region of light emitted from the illumination device 65. The imaging device 66 has a fisheye lens 66A as a camera lens.

  The fisheye lens 66A adopts an equidistant projection method, and has an angle of view of 180 ° or more. As the fisheye lens 66A, for example, model FE185C057HA-1 manufactured by Fuji Film Co., Ltd. (Fujinon) can be used. As shown in FIG. 9, the fish-eye lens 66A is in a state where the closest focus position (referred to as the “shortest imaging position” and indicated by a thick line in FIG. 9) is bent so as to draw an arc around the lens. It has become. The depth of field in the fisheye lens 66A is very deep. The fisheye lens 66A can focus on each position in a range (for example, a range with a dotted pattern in FIG. 9) that is further away from the shortest imaging position. The phrase “in focus” includes not only the case where the focus is strictly, but also the case where the tablet 5 is in focus so that the tablet 5 is hardly blurred in the image obtained by imaging.

  In the present embodiment, the fisheye lens 66A has a shortest imaging distance (a distance from the lens center to the shortest imaging position) that is sufficiently small (for example, 20 mm or less).

  Further, the fisheye lens 66 </ b> A is arranged so that its optical axis coincides with the rotation axis of the revolution motor 61. And the imaging device 66 images the several tablet 5 located in imaging position P1-P6 via the fish-eye lens 66A at a time from diagonally upward side. As a result, as shown in FIG. 10, a plurality of tablets 5 are arranged in an arc shape, and image data ID (luminance image data or color image data) in which the side surface 5A and the upper surface (front surface 5B or back surface 5C) appear in each tablet 5 is displayed. ) Is obtained.

  In the present embodiment, the distance from the fisheye lens 66A to the tablet 5 placed on the placement portion 64 (so-called work distance, for example, 50 mm) is set to be larger than the shortest imaging distance. ing. Therefore, it is possible to focus on each of the side surface 5A and the upper surface (the front surface 5B or the back surface 5C) of the tablet 5 (see FIG. 9). As a result, each part of the tablet 5 and foreign matters attached thereto are clearly displayed. The image data ID can be obtained.

  Image data obtained by the imaging device 66 is converted into a digital signal inside the imaging device 66 and then input to the control processing unit 70 (an image processing device 74 described later) in the form of a digital signal.

  Next, the configuration of the control processing unit 70 will be described. As illustrated in FIG. 5, the control processing unit 70 includes a motion controller 71, a control device 72, an imaging control device 73, and an image processing device 74.

  The motion controller 71 is configured to be able to output a predetermined pulse signal to the revolution motor 61 and the rotation motor 63. By switching on / off of this pulse signal, the operation of both the motors 61, 63 is turned on / off. It switches off. In this embodiment, the revolution motor 61 and the rotation motor 63 rotate while the pulse signal is input.

  In addition, when a predetermined transport control signal is input from the control device 72, the motion controller 71 operates the revolution motor 61 and the rotation motor 63 in a predetermined manner in synchronization. Specifically, the revolving motor revolves the mounted portion 64 by a predetermined angle (36 ° in the present embodiment) and rotates the mounted portion 64 by a predetermined angle (60 ° in the present embodiment). 61 and the rotation motor 63 are operated. As a result, the motion controller 71 rotates one turn (360 °) while the mounted portion 64 revolves half a turn (180 °).

  In the present embodiment, in order to realize the rotation of the placement portion 64 as described above, the radius of the portion of the rotation driving belt 67 that spans the placement portion 64 is R (mm). When the radius of the mounting portion 64 is r (mm) (see FIG. 8), the amount of rotation of the rotation driving belt 67 in one transport operation is (πR−2πr) × (36/180) or (πR + 2πr) × The rotation of the rotation motor 63 is controlled so as to be (36/180). This shifts by 2πr (mm), which is the length of the outer periphery of the mounted portion 64, from πR (mm), which is the length of the portion of the rotation driving belt 67 that spans the mounted portion 64. By setting the feeding amount by the rotation driving belt 67, the guided portion 64 is derived based on the fact that it rotates once (360 °) while it revolves half a circle (180 °). .

  In addition, information relating to the rotation amounts of the motors 61 and 63 is input to the motion controller 71 from the encoders provided in the motors 61 and 63.

  The control device 72 is configured by a PLC (programmable logic controller), and is configured to be able to input and output information (signals) to and from the motion controller 71 and the imaging control device 73. The control device 72 mainly performs control related to the conveyance and imaging of the tablet 5, and basically executes the imaging routine and the conveyance routine repeatedly alternately.

  The imaging routine is an operation for causing the imaging device 66 to perform an imaging operation. Specifically, the imaging routine is an operation of outputting a predetermined imaging control signal to the imaging control device 73.

  The transfer routine executes the transfer operation of rotating the mounted portion 64 by a predetermined angle (60 ° in the present embodiment) while revolving the mounted portion 64 by a predetermined angle (36 ° in the present embodiment). It is an operation to make it. Specifically, this is an operation of outputting the conveyance control signal to the motion controller 71.

  Each time the carrying routine is executed, the placement portion 64 located at the arrangement position P0 moves to the imaging position P1, and the placement portion 64 located at the imaging position P1 moves to the adjacent imaging position P2. In such a manner, the placement parts 64 move to the adjacent positions. Thereby, each tablet 5 mounted on each mounting part 64 will be conveyed at once.

  Further, every time the carrying routine is executed, the orientation of the tablet 5 placed on the placement portion 64 changes. More specifically, as shown in FIG. 11, when the side surface of the tablet 5 is divided into six regions A1 to A6 along the circumferential direction, the fisheye lens among the regions A1 to A6 each time the conveyance routine is executed once. The direction of the tablet 5 is changed so that the regions facing the optical axis of 66A are shifted one by one. As a result, the entire area A1 to A6 of the side surface 5A is arranged on the optical axis side while the placement portion 64 moves from the imaging position P1 to the imaging position P6.

  In addition, information related to the rotation amounts of the revolution motor 61 and the rotation motor 63 is input to the control device 72 via the motion controller 71. The control device 72 determines the execution timing of the transport routine and the imaging routine based on the input information regarding the rotation amount. And according to the determined execution timing, the said imaging control signal and a conveyance control signal are output with respect to the motion controller 71 and the imaging control apparatus 73. FIG.

  The imaging control device 73 controls the imaging of the tablet 5 and controls operations of the imaging device 66 and the illumination device 65 (for example, imaging timing and imaging conditions by the imaging device 66). The imaging control device 73 outputs a predetermined pulse signal to the imaging device 66 when the imaging control signal is input from the control device 72 by executing the imaging routine. Thereby, the imaging operation is performed in the imaging device 66.

  The image processing device 74 is configured as a so-called computer system, and receives image data obtained by the imaging device 66.

  The image processing device 74 includes an image memory, an inspection result storage device, a determination memory, an image / inspection condition storage device, and the like, and various image processing such as binarization processing and block processing, and defect determination processing ( Inspection processing) can be carried out. In the present embodiment, the image processing device 74 constitutes a determination unit and an image processing unit.

  The image memory stores various image data such as image data input from the imaging device 66. An inspection is executed based on the image data stored in the image memory. Of course, when the inspection is executed, the image data may be processed. For example, it is conceivable to perform processing such as masking processing or shading correction. The shading correction is for correcting the lightness variation caused by the difference in position because there is a technical limit to uniformly illuminating the entire tablet 5 with the light of the illumination device 65.

  The test result storage device stores test result data of the tablets 5, statistical data obtained by probabilistically processing the data, and the like. These inspection result data and statistical data can be displayed on a display device (not shown). In addition, a predetermined control signal can be output to the imaging control device 73 based on the inspection result data or the like. In response to this control signal, the imaging control device 73 executes, for example, resetting of imaging conditions and adjustment of illumination.

  The determination memory stores determination values (threshold values, etc.) used for inspection. The determination value is set for each inspection item. The determination values used for the inspection include, for example, the dimensions of the tablet 5 and the like, the shapes and dimensions of various window frames for demarcating various inspection areas, the threshold values for binarization processing, and the determinations regarding the determination of the area and length. Contains values etc. In addition, among the determination values, there is also a determination value that is determined by statistically measuring the inspection measurement results for those determined to be non-defective items in the past inspection.

  The image / inspection condition storage device stores inspection items determined to be defective by the inspection, date and time of defect determination, image data, inspection conditions used for the inspection, and the like.

  Next, the inspection process of the tablet 5 by the appearance inspection apparatus 50 will be described with reference to the flowchart of FIG. Here, for convenience of explanation, the inspection process for one tablet 5T will be described, but actually, the inspection processes for a plurality of tablets 5 are executed in parallel at a time. Further, it is assumed that the tablet 5T is already placed on the placement portion 64 prior to the inspection process.

  As shown in FIG. 12, first, in step S11, the imaging routine and the transport routine are alternately and repeatedly executed to image the tablet 5T at each imaging position P1 to P6. Thereby, a plurality (six in this embodiment) of image data ID1 to ID6 (see FIG. 13) are obtained.

  In the present embodiment, the centers of the different areas A1 to A6 of the tablet 5T are opposed to the optical axis of the fisheye lens 66A at each of the imaging positions P1 to P6. Therefore, the image data ID1 to ID6 includes data related to any one of the areas A1 to A6. In the present embodiment, each of the areas A1 to A6 corresponds to the inspection range. That is, the data relating to the inspection range is acquired for the entire circumference of the side surface 5A.

  When a plurality of image data ID1 to ID6 are acquired, in the subsequent step S12, the tablet 5T (part corresponding to) each image data ID1 to ID6 is used by using an image cutting technique used in general image processing. Are extracted and extracted. Then, data (referred to as “primary image data”) MD1 to MD6 (see FIG. 13) regarding the extracted tablet 5T is stored in the image memory.

  In the subsequent step S13, the primary image data MD1 to MD6 are rotated as necessary using a general image rotation process (for example, affine transformation or the like), and the data ("secondary image data" GD1 to GD6 (refer to FIG. 13). Further, the acquired secondary image data GD1 to GD6 are stored in the image memory.

  Thereafter, in step S14, a portion corresponding to the inspection range in each of the secondary image data GD1 to GD6 is cut out by a general image cutting technique using the window frame, and the cut out portions are connected and connected. Image data CD (see FIG. 13) is obtained. In the present embodiment, the linked image data CD includes not only the side surface 5A but also the front surface 5B or the back surface 5C. Further, the obtained linked image data CD is stored in the image memory.

  In subsequent step S15, binarization processing is performed on the obtained linked image data CD based on the threshold for binarization processing to obtain binarized image data, and the obtained binarized image is obtained. The data is stored again in the image memory. In the binarization processing, the connected image data CD is converted into binarized image data, assuming that a portion having a lightness equal to or higher than the threshold is “1 (bright)” and a portion lower than the threshold is “0 (dark)”. Let In the binarized image data, a part where damage such as a foreign object or a chip exists is “0 (dark)”, and a normal part excluding this part is “1 (bright)”.

  Next, in step S16, determination processing is executed based on the binarized image data stored in the image memory, and the quality of the tablet 5T is determined. In the determination process, first, by performing a block process on the binarized image data, each connected component is specified for “0 (dark)” and “1 (bright)” of the binarized image data, Label the connected components of.

  Furthermore, a connected component corresponding to the foreign matter or the like, that is, a defective area is specified from the connected components of “0 (dark)”. Then, the length of each specified defective area is calculated. The length of the defective area is represented by, for example, the number of dots corresponding to the pixels of the imaging device 66. Then, the quality of the tablet 5T is determined by determining whether or not the calculated length of each defective area is equal to or less than a predetermined determination value. As a result, in this embodiment, the front surface 5B or the back surface 5C is inspected at the same time as the side surface 5A of the tablet 5T. After the pass / fail determination, the inspection process is terminated.

  In the present embodiment, the determination value is set to a value that can be determined as defective when the length of the defective area is 40 μm or more. Each part of the binarized image data is judged to be good or bad based on this judgment value. That is, in the determination process, each part of the binarized image data is determined based on the same inspection condition.

  In addition, the inspection method of the tablet 5 is not limited to what is mentioned here, It can change suitably. For example, the quality of the tablet 5 may be determined based on the calculated area of the defective area while calculating the area of the defective area. Of course, it is good also as combining both.

  Moreover, when a defect is determined in step S16, the tablet 5T is transferred to the defective product storage hopper by the pickup device and stored in the defective product storage hopper. On the other hand, if a non-defective product is determined in step S16, the tablet 5T is transferred downstream (spring chute, etc.) by the pickup device.

  In the present embodiment, the inspection range is set to a range corresponding to 1/6 round centering on the portion facing the optical axis for the following reason. That is, in the image data, the portions located on both sides in the circumferential direction of the side surface 5A of the tablet 5 appear as having a smaller area than the portion located at the center of the side surface 5A, and as a result, foreign matter present in the portion. Etc. will appear as relatively small ones.

  For example, as illustrated in FIG. 14, when it is assumed that the foreign substance BZ is attached to the side surface 5 </ b> A of the tablet 5, when the tablet 5 is viewed in plan, the portion of the tablet 5 that faces the optical axis and the tablet 5 The attachment angle of the foreign matter BZ with respect to the reference line L1 passing through the center is θ1 (°), the angle between the incident light from the foreign matter BZ to the fisheye lens 66A and the reference line L1 is θ2 (°), and the side surface 5A The length of the foreign material along the tangential direction is assumed to be X (μm). At this time, if the diameter of the tablet 5 is 8 mm, and the work distance (distance from the fisheye lens 66A to the tablet 5 placed on the placement part 64) is 50 mm, the length L (μm) of the foreign matter in the image data is , X × sin [90 ° − (θ1 + θ2)].

  In order to correspond to the point where the length L changes in accordance with the attachment angle θ1 and the like in this way, it is conceivable that the inspection conditions are different in each part of the tablet 5 in the image data. The burden increases.

  Therefore, in the present embodiment, when the length X is 50 μm, if the adhesion angle θ1 is 30 ° or less, the length L is 40 μm or more from the above formula, and the inspection range is set to the optical axis. Is a range corresponding to 1/6 circumference centered on the part facing (ie, a range of ± 30 ° centered on the part). By setting the inspection value in this way and setting a determination value so as to be determined as defective when there is a defective area having a length of 40 μm or more, the length can be changed without changing the inspection conditions in each part. Can detect foreign matters of 50 μm or more, and the detection accuracy can be sufficiently increased.

  However, the inspection range given here is only an example that can be set when the size and work distance of the tablet 5 are set to the above-described numerical values, and the inspection range is used when determining the size, work distance, and quality of the tablet 5. It is changed as appropriate based on the determination value. In addition, according to the change of the inspection range, it is necessary to change the revolution angle and the rotation angle of the placement portion 64 when the carrying routine is executed once.

  As described above in detail, according to the present embodiment, image data in which the tablets 5 and the like are clearly expressed can be obtained by performing imaging through the fisheye lens 66A.

  The tablet 5 is imaged while being conveyed along an arcuate conveyance path centered on the optical axis of the fish-eye lens 66A. Therefore, without specially correcting the position of the tablet 5, the distance from the fisheye lens 66A to the tablet 5 and the incident angle of light from the tablet 5 with respect to the fisheye lens 66A can be made substantially the same at each of the imaging positions P1 to P6. As a result, in the obtained image data, it is possible to more reliably prevent the tablet 5 from being deformed (distorted) or the tablet 5 from being varied in size.

  As described above, according to the present embodiment, the image data in which the tablet 5 and the like are clearly displayed and the tablet 5 has almost no deformation or size variation is obtained without performing the position correction of the tablet 5 in particular. Thus, the entire circumference of the side surface 5A can be obtained without causing a decrease in inspection efficiency. Therefore, the entire circumference of the side surface 5A can be inspected accurately and quickly, and very good performance can be obtained in both inspection accuracy and inspection efficiency.

  In addition, since only one imaging device 66 is sufficient for obtaining the above-described effects, the appearance inspection device 50 can be reduced in size and simplified, and the cost can be reduced. In addition, in the present embodiment, since the means for rotating the mounted portion 64 while revolving is realized with a relatively simple configuration, the appearance inspection apparatus 50 can be more effectively downsized. it can.

  Furthermore, in this embodiment, it is possible to perform inspection by excluding the portions of the image data located on both ends in the circumferential direction of the side surface 5A from the inspection target. Thereby, as above-mentioned, the test | inspection of the tablet 5 can be performed on the same test | inspection conditions. As a result, it is possible to maintain good inspection accuracy while reducing the processing load.

  Further, by performing an inspection based on one connected image data CD, the entire circumference of the side surface 5A can be easily inspected under the same inspection conditions. As a result, it is possible to further reduce the processing load while maintaining good inspection accuracy.

  In addition, in this embodiment, since the front surface 5B or the back surface 5C is also imaged in addition to the side surface 5A, the front surface 5B or the back surface 5C can be inspected together with the side surface 5A. Therefore, it is not necessary to separately inspect the front surface 5B and the back surface 5C, and the time required for the inspection can be shortened.

  In addition, according to the present embodiment, the image data regarding the plurality of tablets 5 can be obtained at a time, and therefore the inspection efficiency can be further improved.

  In addition, it is not limited to the description content of the said embodiment, For example, you may implement as follows. Of course, other application examples and modification examples not illustrated below are also possible.

  (A) In the said embodiment, it is comprised so that the image data for the perimeter of the side surface 5A of the tablet 5 may be obtained in the state which made one side of the surface 5B and the back surface 5C the upper surface. That is, when obtaining the image data, the front and back sides of the tablet 5 are not particularly reversed. On the other hand, you may comprise so that the image data for the perimeter of the said side 5A at least may be obtained in both the state which reversed the front and back of the tablet 5, and the state which is not reversed. In this case, the inspection can be performed based on the image data in both the state where the front and back of the tablet 5 are not reversed and the state where the tablet 5 is reversed. Thereby, the influence on the test | inspection by the difference in the direction of the tablet 5 (whether the tablet 5 is reversed upside down) can be eliminated, and the further improvement of a test | inspection precision can be aimed at.

  The reversing means for reversing the tablet 5 is provided in the middle of the transport path of the tablet 5. For example, the reversing means may be constituted by a mechanism including a gripping means for gripping the side surface of the tablet 5 and a rotating means for rotating the gripping means to reverse the front and back of the gripped tablet 5. it can.

  (B) In the above embodiment, the angle of view of the fisheye lens 66A is about 180 °, but the angle of view of the fisheye lens 66A is not limited to this. The angle of view of the fisheye lens 66 </ b> A may be an angle of view that can capture at least the tablet 5 placed on the placement portion 64.

  (C) In the above-described embodiment, the placement portion 64 is rotated by the rotation motor 63, but the placement portion 64 may be rotated by the driving force of the revolution motor 61. Good. That is, you may comprise so that the mounting part 64 may rotate and revolve by one power source.

  (D) In the above embodiment, the appearance inspection device 50 is provided in the tablet supply device 15, but the arrangement position of the appearance inspection device 50 can be changed as appropriate. Further, the appearance inspection apparatus 50 may be provided separately from the PTP packaging machine 10. Furthermore, in the PTP packaging machine 10, only one appearance inspection device 50 or a plurality of appearance inspection devices 50 may be provided.

  (E) In the above embodiment, the case in which the object to be inspected is a disc-shaped tablet 5 is embodied, but the object to be inspected is atypical tablets or capsules (pharmaceuticals, nutritional foods, etc.), and a hole is formed in the center. Other than circular tablets such as circular tablets may be used. In addition, the size of the object to be inspected may vary depending on the difference in tablet diameter, capsule number, and the like. According to the above embodiment, at the time of imaging, each part of the inspection object can be focused, and as a result, image data in which the inspection object or the like is clearly displayed can be obtained. Therefore, various types of inspection objects can be inspected, and excellent versatility can be obtained.

  (F) The material of the container film 3 and the cover film 4 is not limited to what was mentioned in the said embodiment, It can change suitably.

  DESCRIPTION OF SYMBOLS 5 ... Tablet (inspection object), 5A ... Side surface, 5B ... Front surface, 5C ... Back surface, 50 ... Appearance inspection apparatus, 61 ... Revolution motor, 62 ... Revolution table, 63 ... Rotation motor, 64 ... Mounted part, 66 DESCRIPTION OF SYMBOLS ... Imaging device, 66A ... Fisheye lens, 67 ... Autorotation drive belt, 74 ... Image processing apparatus (determination means, image processing means), CD ... Connection image data, ID ... Image data.

Claims (7)

Conveying means for conveying a predetermined object to be inspected;
Imaging means for imaging the object to be inspected conveyed by the conveying means via a lens;
A visual inspection apparatus comprising: a determination unit that determines the quality of the inspection object based on the image data acquired by the imaging unit;
The lens is a fisheye lens;
The transport means rotates a part to be inspected along a circular or circular transport path centered on the optical axis of the fisheye lens to locate a part positioned on the optical axis side of the side surface of the test object. While changing, sequentially convey the inspection object to a plurality of imaging positions,
The imaging means is configured to acquire image data for the entire circumference of the side surface by imaging at least the side surface of the inspection object every time the inspection object is arranged at the imaging position. An appearance inspection apparatus characterized by comprising: The conveying means is
A rotation means for changing the portion of the side surface located on the optical axis side by rotation of the placement portion, and a placement portion on which the inspection object is placed;
The appearance inspection apparatus according to claim 1, further comprising: a revolving unit that moves the placement unit along the transport path about the optical axis. The object to be inspected has a circular outer shape in a plan view,
The imaging means obtains data for an inspection range, which is a range smaller than a half circumference along a circumferential direction of the side surface, centered on a portion facing the optical axis in the inspection object, for the entire circumference of the side surface. So that the inspection object is imaged,
The appearance inspection apparatus according to claim 1, wherein the determination unit is configured to determine whether the inspection object is good based on data of the inspection range in the image data. The image processing means for extracting data corresponding to the inspection range in a plurality of the image data, and creating connected image data in which each extracted data is continuous for the entire circumference of the side surface,
The appearance inspection apparatus according to claim 3, wherein the determination unit is configured to determine the quality of the inspection object based on the connected image data. The inspection object has a front surface and a back surface that sandwich the side surface,
The imaging means images at least one of the front surface and the back surface together with the side surface,
The determination unit is configured to determine whether or not the inspection object is good based on data of the at least one surface imaged by the imaging unit in the image data. 5. An appearance inspection apparatus according to any one of items 4 to 4. The inspection object has a front surface and a back surface that sandwich the side surface,
The imaging means is configured to acquire image data for the entire circumference of the side surface in both a state where the front and back of the inspection object are not reversed and a state where the surface is reversed. The appearance inspection apparatus according to any one of claims 1 to 5. The transport means transports a plurality of objects to be inspected at a time so that the objects to be inspected are arranged at the respective imaging positions,
The appearance inspection according to any one of claims 1 to 6, wherein the imaging unit is configured to image a plurality of the inspection objects arranged at the respective imaging positions at a time. apparatus.

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