Tablet inspection device

Abstract

Provided is a tablet inspection device capable of achieving a simple and compact structure, etc. A tablet inspection device (23) is provided with: optical path conversion sheets (62a-62d) capable of converting the optical path of light reflected at one side surface region of a tablet; and an imaging optical system (66) that forms an image of the light, the optical path of which has been converted by the optical path conversion sheets (62a-62d), onto the imaging element (64c), and determines whether or not the side surface section is qualified on the basis of image data obtained from the light formed on the imaging element (64c). A plurality of optical path conversion sheets (62a-62d) are provided across a plurality of rows of tablets (5) in the transport direction of the tablets when viewed from the imaging element (64c) side. The plurality of optical path conversion sheets (62a-62d) respectively correspond to different side surface regions, and convert the optical path of the light reflected at the corresponding side surface region into an optical path along the optical axis direction of the imaging optical system (66). The entire outer periphery of the side surface section of the tablet is covered by a plurality of one-side surface regions corresponding to the respective optical path conversion sheets (62a-62d).

Description

Technical Field

[0001] The present invention relates to a tablet inspection device for inspecting the side faces of tablets. Background Art

[0002] Conventionally, there has been known a tablet inspection device including: a photographing mechanism for photographing tablets being transported, and a determination mechanism for determining whether a tablet is qualified based on the image data obtained by the photographing mechanism. As a tablet inspection device, there is a device capable of determining whether the side faces of tablets are qualified (for example, see Patent Document 1, etc.).

[0003] The tablet inspection device related to Patent Document 1 above includes: an illumination device that irradiates a prescribed light onto a tablet transported to a prescribed inspection area; a plurality (six) of cameras located around the inspection area and photographing the tablet from an oblique upper direction; and an image processing mechanism for performing an inspection related to the side face of the tablet based on the image data obtained by the cameras. The cameras include: a photographing element (for example, a CCD area sensor) in which a plurality of light receiving elements are arranged in a two-dimensional array, and an imaging optical system (lens unit) that images the image of the tablet located within the inspection area onto the photographing element. The photographing optical system is constituted by an object-side telecentric optical system or a bilateral telecentric optical system. Further, for a plurality of tablets located within the inspection area, the light receiving surface of the photographing element and the principal plane of the photographing optical system are set to satisfy an anti-flicker condition. With such a configured tablet inspection device, regardless of the distance between the photographing element and the tablet, the sizes of the plurality of tablets in the image data can be made substantially the same, and image data in which all the tablets located within the inspection area are in focus can be acquired. Thereby, the inspection accuracy of the image processing mechanism can be improved.

[0004] In addition, as a tablet inspection device, there is known the following structure, having: a rotary drum that transports tablets in a state of being adsorbed and arranged in multiple columns; and an annular prism that is arranged so as to surround the side face of the adsorbed tablet, and the annular prism can be used to acquire image data of the entire circumference of the side face of the tablet (for example, see Patent Document 2, etc.).

[0005] [Prior Art Documents]

[0006] [Patent Documents]

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2019-39762

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 5-87744 Summary of the Invention

[0009] [Problems to be Solved by the Invention]

[0010] However, the tablet inspection device disclosed in Patent Document 1 utilizes an object-side telecentric optical system, among other features. Furthermore, the light-receiving surface of the imaging element and the main surface of the imaging optical system must meet anti-flicker requirements for multiple tablets, potentially leading to an increase in camera size. Furthermore, to avoid physical interference between the multiple cameras, they must be positioned sufficiently far from the tablets. This, combined with the increased size of the cameras, can ultimately lead to an increase in the overall size of the device.

[0011] Furthermore, in the tablet inspection apparatus related to Patent Document 2, whenever the shape or size of the tablet to be inspected changes, the annular prism needs to be replaced or adjusted to suit the tablet, which results in low inspection convenience and efficiency.

[0012] The present invention has been proposed in view of the above-mentioned situation, and an object of the present invention is to provide a tablet inspection device that can realize a simple and compact structure while improving the convenience and efficiency of inspection.

[0013] [Solutions to solve the problem]

[0014] The following describes each solution for achieving the above-mentioned objectives in detail, and, where necessary, provides additional notes on the unique effects of each solution.

[0015] Solution 1: A tablet inspection device for inspecting the side surfaces of a plurality of tablets transported in a plurality of rows, characterized in that the tablet inspection device comprises:

[0016] an irradiation mechanism for irradiating a plurality of tablets with predetermined light;

[0017] an imaging element for imaging the light emitted from the irradiation mechanism;

[0018] an optical path conversion sheet capable of converting the optical path of light irradiated from the irradiation mechanism and reflected from a circumferentially continuous side surface area of the side surface portion,

[0019] an imaging optical system that images the light after the optical path conversion by the optical path conversion sheet onto the photographing element, and

[0020] a determination unit capable of determining whether the side surface portion is acceptable based on image data obtained by the light formed into an image on the imaging element,

[0021] The optical path conversion sheet is configured to span multiple rows of tablets when viewed from the imaging element side, and a plurality of the optical path conversion sheets are provided along the tablet conveying direction.

[0022] A plurality of the optical path conversion sheets respectively correspond to different ones of the side surface regions, and are configured to convert the optical path of the light reflected at the corresponding side surface region into an optical path along the optical axis direction of the imaging optical system.

[0023] It is further configured such that the entire outer periphery of the side surface portion is covered by the plurality of side surface regions corresponding to the respective optical path conversion sheets.

[0024] According to the above-described Solution 1, the optical path conversion sheets are configured such that, when viewed from the side of the imaging element, they straddle multiple columns of the tablets and are arranged in the tablet conveyance direction. Moreover, the light whose optical path has been converted by the optical path conversion sheets passes through the imaging optical system to be imaged by the imaging element. Therefore, the device can simultaneously image and inspect multiple tablets, and can simplify the structure of the device (camera) having the imaging element or the tablet inspection device itself, and further can more reliably miniaturize and simplify the tablet inspection device. In addition, it is not necessary to provide multiple devices (cameras) having imaging elements to image multiple tablets, and thus, the miniaturization of the tablet inspection device can be further achieved. As a result, the tablet inspection device can be designed to have a simple and compact structure.

[0025] In addition, according to the above-described Solution 1, multiple optical path conversion sheets are arranged in the tablet conveyance direction, and the entire outer periphery of the side surface portion of the tablet is covered by the plurality of side surface regions corresponding to the respective optical path conversion sheets. Therefore, it is possible to inspect the entire outer periphery of the side surface portion of the tablet.

[0026] In addition, even when the shape or size of the tablets to be inspected is changed, it is not necessarily required to replace or adjust the optical path conversion sheets. Therefore, the convenience and efficiency of the inspection can be improved.

[0027] Furthermore, according to the above-described Solution 1, a plurality of optical path conversion sheets respectively correspond to different side surface regions, and convert the optical path of the light reflected at the corresponding side surface region into an optical path along the optical axis direction of the imaging optical system. Therefore, it is possible to suppress the influence of the light reflected at other parts of the tablet on the part related to the side surface region in the image data, and make the contours and shapes of the part related to the side surface region and the defective parts (such as stains or defects, etc.) located in the side surface region in the image data clearer. As a result, it is possible to accurately determine the presence or absence of defective parts in the side surface portion and more accurately specify the positions of the defective parts.

[0028] Solution 2: The tablet inspection device according to Solution 1, wherein the imaging optical system is configured to form an object-side telecentric optical system and has an aperture capable of adjusting the light imaged in the imaging element.

[0029] According to the above-mentioned Solution 2, the light that forms an image on the imaging element among the light whose optical path is converted by the optical path conversion sheet can be adjusted by the aperture. Therefore, based on the inspection, appropriate image data can be obtained more reliably and easily.

[0030] Solution 3: The tablet inspection device according to Solution 1, characterized in that the imaging optical system has an object-side lens for focusing the light whose optical path is converted by the optical path conversion sheet.

[0031] The object-side lens is a Fresnel lens.

[0032] According to the above-mentioned Solution 3, since the object-side lens is a Fresnel lens, the thickness of the object-side lens can be designed to be relatively thin. This enables the device to adopt a more compact structure.

[0033] Solution 4: The tablet inspection device according to Solution 1, characterized in that a plurality of protruding strip portions arranged in parallel are formed on the surface of the optical path conversion sheet.

[0034] The protruding strip portion has:

[0035] A basic vertical plane, the angle of the angle formed by the basic vertical plane in a cross-section perpendicular to the extending direction of the protruding strip portion with respect to the flat back surface of the optical path conversion sheet is 80° or more and 95° or less; and

[0036] An inclined plane, the angle of the angle formed by the inclined plane in the cross-section with respect to the back surface is 10° or more and 55° or less.

[0037] According to the above-mentioned Solution 4, each optical path conversion sheet can more reliably convert the optical path of the light reflected in the corresponding side surface area into the optical path along the optical axis direction of the imaging optical system, and at the same time, can more effectively prevent the optical path of the light reflected in other parts of the tablet from being converted into the optical path along the optical axis direction. Thus, in the image data, the contours and shapes of the parts related to the side surface area or the non-conforming parts can be made clearer more reliably. As a result, the presence or absence of non-conforming parts in the side surface part can be determined with higher accuracy, and the position of the non-conforming parts can be specified more accurately.

[0038] Solution 5: The tablet inspection device according to Solution 1, characterized in that the irradiation mechanism is arranged between the plurality of optical path conversion sheets.

[0039] According to the above-mentioned Solution 5, since the irradiation mechanism can be accommodated between the optical path conversion sheets, further miniaturization of the device can be achieved.

[0040] Solution 6: The tablet inspection device according to Solution 1 is characterized in that the imaging optical system is configured to form an image on the imaging element of light that passes between the plurality of optical path conversion sheets and is reflected by a surface of the tablet facing the imaging element.

[0041] The determination unit can determine whether the surface of the tablet facing the imaging element is acceptable based on the image data.

[0042] According to the sixth aspect, not only the side surfaces of the tablet can be inspected, but also the surface of the tablet facing the imaging element can be inspected, thereby further improving the efficiency of tablet inspection.

[0043] In addition, the technical features associated with the above solutions may be appropriately combined. For example, the technical features associated with solution 2 may be combined with the technical features associated with solution 3. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a three-dimensional diagram showing a PTP sheet.

[0045] Figure 2 This is a partially enlarged cross-sectional view of the PTP sheet.

[0046] Figure 3 It is a perspective view showing a PTP film.

[0047] Figure 4 This is a schematic diagram showing the general structure of a PTP packaging machine.

[0048] Figure 5 It is a partial cross-sectional schematic diagram showing the general structure of a tablet inspection and filling device.

[0049] Figure 6 It is a partially enlarged stereoscopic view of a tablet filling device.

[0050] Figure 7 This is a block diagram showing the general structure of a tablet filling device.

[0051] Figure 8 This is a perspective view of a tablet inspection device.

[0052] Figure 9 It is along Figure 8 Schematic diagram of the cross section of the JJ line.

[0053] Figure 10 It is along Figure 8 Schematic cross-section of the KK line.

[0054] Figure 11 It is a planar schematic diagram of the tablet and the optical path conversion sheet.

[0055] Figure 12 It is a three-dimensional schematic diagram of an optical path conversion sheet for indicating the extending direction of the rib portion.

[0056] Figure 13 It is an enlarged planar schematic diagram for explaining a side surface area.

[0057] Figure 14 It is an enlarged cross-sectional schematic diagram of the optical path conversion sheet.

[0058] Figure 15 It is a cross-sectional schematic diagram of a tablet inspection device when photographing a tablet at the first position in the case of obtaining a cross-section parallel to the conveying direction of the tablet.

[0059] Figure 16 It is a cross-sectional schematic diagram of a tablet inspection device when photographing a tablet at the first position in the case of obtaining a cross-section perpendicular to the conveying direction of the tablet.

[0060] Figure 17 It is a schematic diagram showing a part of the image data obtained by photographing a tablet at the first position.

[0061] Figure 18 It is a cross-sectional schematic diagram of a tablet inspection device when photographing a tablet at the second position.

[0062] Figure 19 It is a schematic diagram showing a part of the image data obtained by photographing a tablet at the second position.

[0063] Figure 20 It is a cross-sectional schematic diagram of a tablet inspection device when photographing a tablet at the third position in the case of obtaining a cross-section parallel to the conveying direction of the tablet.

[0064] Figure 21 It is a cross-sectional schematic diagram of a tablet inspection device when photographing a tablet at the third position in the case of obtaining a cross-section perpendicular to the conveying direction of the tablet.

[0065] Figure 22 It is a schematic diagram showing a part of the image data obtained by photographing a tablet at the third position.

[0066] Figure 23 It is a cross-sectional schematic diagram of a tablet inspection device when photographing a tablet at the fourth position.

[0067] Figure 24 It is a schematic diagram showing a part of the image data obtained by photographing a tablet at the fourth position.

[0068] Figure 25 It is a cross-sectional schematic diagram of the lighting device in other embodiments.

[0069] Figure 26 It is a three-dimensional schematic diagram of the optical path conversion sheet in other embodiments.

[0070] Figure 27 It is a cross-sectional schematic diagram of a tablet inspection device that can photograph the front or back surface of a tablet between multiple optical path conversion sheets in other embodiments.

[0071] Figure 28 It is a cross-sectional schematic diagram of a tablet inspection device in which an illumination device is arranged between optical path conversion sheets in other embodiments.

[0072] Figure 29 It is a cross-sectional schematic diagram of a tablet inspection device in which the front and back of the optical path conversion sheet are changed in other embodiments.

[0073] Figure 30 It is a partial cross-sectional schematic diagram of the general configuration of a tablet inspection device or the like that takes tablets filled in a bag portion as an inspection object in other embodiments. Detailed implementation manners

[0074] Hereinafter, an embodiment will be described with reference to the accompanying drawings. First, the configuration of the PTP sheet will be described in detail.

[0075] As Figure 1 , Figure 2 shown, the PTP sheet 1 has: a container film 3 having a plurality of bag portions 2, and a cover film 4 mounted on the container film 3 so as to cover the bag portions 2.

[0076] The container film 3 is made of a transparent thermoplastic resin material such as polypropylene (PP) or polyvinyl chloride (PVC), and has light transmissivity. On the other hand, the cover film 4 is composed of an opaque material (such as aluminum foil, etc.) coated with a sealant made of, for example, polypropylene resin. Of course, the materials of the respective films 3 and 4 are not limited thereto, and other materials may be used.

[0077] The PTP sheet 1 is manufactured by stamping a strip-shaped PTP film 6 formed by a strip-shaped container film 3 and a strip-shaped cover film 4 (see Figure 3 ) into a sheet shape, and is formed to be substantially rectangular in plan view. In the PTP sheet 1, a bag row formed by five bag portions 2 arranged along its length direction is formed in two rows in its width direction. That is, a total of ten bag portions 2 are formed.

[0078] In each bag portion 2, one tablet 5 is respectively accommodated. The tablet 5 in this embodiment is a plain tablet in the shape of a disc that is circular in plan view, and has a side surface portion 5a that is circular in plan view, and a front surface portion 5b and a back surface portion 5c that sandwich the side surface portion 5a.

[0079] Next, with reference toFigure 4 Describe the general structure of the PTP packaging machine 10 that can manufacture the above-mentioned PTP sheet 1.

[0080] As Figure 4 shown, at the uppermost upstream side of the PTP packaging machine 10, the raw material roll of the strip-shaped container film 3 is wound into a roll shape. The leading end side of the container film 3 wound into a roll shape is guided by a guide roller 13. The container film 3 is hung on an intermittent feeding roller 14 on the downstream side of the guide roller 13. The intermittent feeding roller 14 is connected to an intermittently rotating motor and is used to intermittently transport the container film 3.

[0081] Between the guide roller 13 and the intermittent feeding roller 14, a heating device 15 and a bag portion forming device 16 are successively arranged along the transport path of the container film 3. Moreover, in a state where the container film 3 is heated by the heating device 15 and becomes relatively soft, a plurality of bag portions 2 are formed at a specified position of the container film 3 by the bag portion forming device 16. The formation of the bag portions 2 is carried out during the gap between the transport operations of the container film 3 by the intermittent feeding roller 14.

[0082] The container film 3 sent out from the intermittent feeding roller 14 is successively hung on a tension roller 18, a guide roller 19, and a film receiving roller 20. The film receiving roller 20 is connected to a motor that rotates at a constant speed, so the container film 3 can be transported continuously and at a constant speed. The tension roller 18 is in a state of pulling the container film 3 toward the tension side by an elastic force to prevent the container film 3 from loosening due to the difference in the transport operations between the intermittent feeding roller 14 and the film receiving roller 20, so as to always keep the container film 3 in a tensioned state.

[0083] Between the guide roller 19 and the film receiving roller 20, a tablet inspection and filling device 21 is arranged along the transport path of the container film 3. The tablet inspection and filling device 21 inspects the tablets 5 and fills the tablets 5 into the bag portions 2 at the same time. The detailed structure of the tablet inspection and filling device 21 will be described later.

[0084] On the other hand, the raw material roll of the strip-shaped cover film 4 is wound into a roll shape at the uppermost upstream side. The leading end of the cover film 4 wound into a roll shape is guided by a guide roller 24 to the side of the heating roller 25.

[0085] The heating roller 25 can be pressed against the aforementioned film receiving roller 20 to feed the container film 3 and the cover film 4 between the two rollers 20 and 25. Moreover, the container film 3 and the cover film 4 pass between the two rollers 20 and 25 in a heated and pressed state, whereby the cover film 4 is mounted on the container film 3 and the bag portions 2 are sealed by the cover film 4. Thus, a strip-shaped PTP film 6 in which the tablets 5 are stored in the respective bag portions 2 is manufactured.

[0086] The PTP film 6 sent out from the film receiving roller 20 is successively hung on the tension roller 27 and the intermittent feeding roller 28. Since the intermittent feeding roller 28 is connected to an intermittently rotating motor, the PTP film 6 is transported intermittently. The tension roller 27 is in a state of tightening the PTP film 6 toward the tension side by an elastic force, so as to prevent the PTP film 6 from slackening due to the difference in the transporting action between the film receiving roller 20 and the intermittent feeding roller 28, thereby always keeping the PTP film 6 in a tensioned state.

[0087] The PTP film 6 sent out from the intermittent feeding roller 28 is successively hung on the tension roller 31 and the intermittent feeding roller 32. Since the intermittent feeding roller 32 is connected to an intermittently rotating motor, the PTP film 6 is transported intermittently. The tension roller 31 is in a state of tightening the PTP film 6 toward the tension side by an elastic force, thereby preventing the PTP film 6 from slackening between the intermittent feeding rollers 28 and 32.

[0088] Between the intermittent feeding roller 28 and the tension roller 31, a slit forming device 33 and an engraving device 34 are successively arranged along the transporting path of the PTP film 6. The slit forming device 33 has a function of forming a cutting slit at a specified position of the PTP film 6. The engraving device 34 has a function of imparting an engraving at a specified position of the PTP film 6. In addition, in Figure 1 etc., the illustration of the cutting slit and the engraving is omitted.

[0089] The PTP film 6 sent out from the intermittent feeding roller 32 is successively hung with a tension roller 35 and a continuous transporting roller 36 on its downstream side. Between the intermittent feeding roller 32 and the tension roller 35, a sheet punching device 37 is arranged along the transporting path of the PTP film 6. The sheet punching device 37 has a function of punching the PTP film 6 at the outer edge in units of PTP sheets 1, that is, a function of cutting off the PTP sheet 1 from the PTP film 6.

[0090] The PTP sheet 1 obtained by the sheet punching device 37 is transported by the conveyor belt 39 and temporarily stored in the finished product hopper 40. However, if the tablet inspection and filling device 21 determines a non-conforming product, the PTP sheet 1 related to this non-conforming determination will not be fed into the finished product hopper 40, but will be separately discharged through a non-conforming sheet discharging mechanism (not shown).

[0091] A cutting device 41 is arranged on the downstream side of the continuous transporting roller 36. After being punched by the sheet punching device 37, the unnecessary film part 42 that constitutes the remaining waste part in a strip shape is guided through the tension roller 35 and the continuous transporting roller 36 and then introduced into the cutting device 41. The cutting device 41 cuts the unnecessary film part 42 to a specified size. After the cut unnecessary film part 42 is stored in the waste hopper 43, it is separately disposed of.

[0092] Next, the tablet inspection and filling device 21 will be described. Figure 5is a partial cross-sectional schematic diagram showing the general configuration of the tablet inspection and filling device 21 and the like. As Figure 5 shown, the tablet inspection and filling device 21 includes a tablet filling device 22 and a tablet inspection device 23. In addition, the operations of the tablet filling device 22 and the tablet inspection device 23 are controlled by a control device (not shown).

[0093] The tablet filling device 22 is sequentially provided with a storage unit 51, a supply tank 52, a rotating drum 53, and an adsorption belt 54 along the supply path of the tablets 5 from the upstream side.

[0094] The storage unit 51 can store a large number of tablets 5 and sequentially supply the tablets 5 to the supply tank 52 from here.

[0095] The supply tanks 52 are respectively provided at positions corresponding to the positions of the respective bag portions 2 in the width direction of the horizontally transported container film 3 ( Figure 5 the depth direction of the paper surface of the drawing). That is, in the present embodiment, five supply tanks 52 are arranged side by side in the width direction of the container film 3. Each supply tank 52 is cylindrical and is configured to be able to load the tablets 5 vertically in a row in a horizontal posture.

[0096] Near the lower opening of each supply tank 52, a gate 52a for opening and closing the lower opening is provided. Moreover, by performing the opening and closing operation of the gate 52a, the tablets 5 can be made to fall naturally one by one from the supply tank 52 and supplied to the rotating drum 53.

[0097] After receiving the tablets 5 supplied from the supply tank 52, the rotating drum 53 adsorbs and holds the tablets 5 and at the same time transports them to the adsorption belt 54 side. The rotating drum 53 is cylindrical and is pivotally supported so as to be rotatable, and is rotationally driven by a driving device such as a motor.

[0098] In addition, as Figure 6 shown, a plurality of adsorption portions 53a for adsorbing and holding the tablets 5 are formed on the outer peripheral surface of the rotating drum 53. The adsorption portions 53a are regularly arranged at regular intervals in the circumferential and axial directions of the rotating drum 53. In the present embodiment, five rows of adsorption portions 53a arranged in the circumferential direction of the rotating drum 53 are equidistantly provided in the direction of the rotation axis of the rotating drum 53.

[0099] In addition, while each adsorption part 53a moves from directly above the rotation axis of the rotary drum 53 to near directly below as it rotates with the rotary drum 53, a state of being evacuated (i.e., a state in which negative pressure is supplied) is formed by a prescribed vacuum pump (not shown). Thus, each adsorption part 53a adsorbs and holds the tablets 5 while moving from directly above the rotation axis of the rotary drum 53 to near directly below. On the other hand, while each adsorption part 53a moves from directly below the rotation axis of the rotary drum 53 to near directly above as it rotates with the rotary drum 53, it is in a state of being open to the atmosphere. Therefore, the tablets 5 adsorbed and held on the rotary drum 53 are desorbed directly below the rotation axis of the rotary drum 53.

[0100] Based on receiving the tablets 5 from the rotary drum 53, the adsorption belt 54 adsorbs and transports the tablets 5 and finally fills them into the container film 3 (bag part 2). As Figure 5 , Figure 6 shown, the adsorption belt 54 includes: a pair of pulleys 54a, 54b, a conveyor belt 54c formed by connecting a plurality of holding plates 54d in a belt shape, and a suction mechanism (not shown).

[0101] The pair of pulleys 54a, 54b are arranged at regular intervals along the transport path of the container film 3, and are each rotatable about a rotation axis parallel to the rotation axis of the rotary drum 53 by a prescribed drive mechanism.

[0102] The conveyor belt 54c is bridged between the pair of pulleys 54a, 54b and rotates and moves as the pulleys 54a, 54b rotate. The portion of the conveyor belt 54c that moves from the pulley 54b to the pulley 54a (i.e., the portion of the outer peripheral surface of the conveyor belt 54c facing downward) is arranged close to the transport path of the container film 3 and continuously moves at the same speed as the transport speed of the container film 3 transported by the film receiving roller 20.

[0103] In addition, a plurality of adsorption holes 54e are provided at regular intervals in the width direction of the conveyor belt 54c on each holding plate 54d. In the present embodiment, five columns of adsorption holes 54e arranged in the circumferential direction of the conveyor belt 54c are provided at regular intervals in the width direction of the conveyor belt 54c.

[0104] In addition, it is configured such that by activating the above-described suction mechanism, each adsorption hole 54e can be placed in a vacuum state (i.e., a state in which negative pressure is supplied). Thus, the adsorption belt 54 can adsorb and hold the tablets 5 at the formation positions of the respective adsorption holes 54e.

[0105] Furthermore, an air blowing mechanism (not shown) is provided inside the suction belt 54. This blowing mechanism blows pressurized air toward the suction holes 54e. The air blowing mechanism releases the suction belt 54 from adsorbing the tablets 5. In this embodiment, the air blowing mechanism releases the tablets 5, allowing the tablets 5 to be filled into the bag 2 at a predetermined filling position (in this embodiment, directly below the rotation axis of the pulley 54a).

[0106] Next, the tablet inspection device 23 will be described. The tablet inspection device 23 is provided corresponding to the conveying path of the tablet 5 from the pulley 54a to the pulley 54b, and is used to inspect the side portions 5a of the tablets 5 conveyed in a multi-row parallel state. [[ID=�4]]Figures 7 - 10 As shown, the tablet inspection device 23 is equipped with an illumination device 61, optical path conversion sheets 62a, 62b, 62c, and 62d, an object-side lens 63, a camera 64, and an image processing device 65. Furthermore, the tablet inspection device 23 may be equipped with a display mechanism for displaying information stored in the image processing device 65, and an input mechanism (e.g., a keyboard) for inputting information into the image processing device 65. In this embodiment, the illumination device 61 constitutes the "illumination mechanism," and the image processing device 65 constitutes the "determination mechanism." Hereinafter, the optical path conversion sheets 62a, 62b, 62c, and 62d will be simply referred to as "optical path conversion sheets 62a to 62d."

[0107] The lighting device 61 irradiates the tablets 5 with a predetermined light source (e.g., ultraviolet light). The lighting device 61 includes a light source 61a, such as an LED, and a light guide plate 61b. The light guide plate 61b guides the light emitted by the light source 61a to the tablets 5. Alternatively, the light guide plate 61b can be a thin plate, such as acrylic, with a dot patterned surface, such as by printing or ultrasonic techniques, to achieve surface illumination.

[0108] The light guide plate 61b emits light from the light source 61a toward the tablet 5 side, but does not emit light toward the opposite side (camera 64 side) of the tablet 5. The light guide plate 61b is configured to transmit light reflected by the tablet 5.

[0109] The optical path conversion sheets 62a to 62d are used to convert the side regions AR1, AR2, AR3, and AR4 (see FIG. Figure 13 ) is converted into an optical path along the optical axis OA of the imaging optical system 66 (an optical path parallel to the optical axis OA). In addition, the side surface areas AR1, AR2, AR3, and AR4 are hereinafter simply referred to as "side surface areas AR1 to AR4".

[0110] The optical path conversion sheets 62a to 62d are disposed between the illumination device 61 and the tablet 5 (adsorption belt 54), and are provided at regular intervals along the conveyance direction of the tablet 5. Further, the optical path conversion sheets 62a to 62d (particularly the flat back surface 62r, see Figure 14 ) are arranged perpendicular to the optical axis OA and parallel to the conveyance direction of the tablet 5. Further, when viewed from the side of the camera 64 (imaging element 64c described later), the optical path conversion sheets 62a to 62d are arranged so as to straddle multiple columns of the tablet 5 (five columns in this embodiment) (see Figure 11 ).

[0111] Further, the optical path conversion sheets 62a to 62d respectively correspond to different side surface regions AR1 to AR4, and convert the optical path of the light reflected in the corresponding side surface regions AR1 to AR4 into a direction along the optical axis OA. And the entire outer periphery of the side surface portion 5a is covered by the corresponding side surface regions AR1 to AR4 of the optical path conversion sheets 62a to 62d. <00>

[0112] In this embodiment, the side surface region AR1 corresponding to the optical path conversion sheet 62a is a region composed of all regions of the left side surface portion 5a1 in the side surface portion 5a, a part of the downstream side surface portion 5a2, and a part of the upstream side surface portion 5a3 (see Figure 13 ). The left side surface portion 5a1 is a part on one end side in the width direction of the adsorption belt 54 in the side surface portion 5a. Further, the downstream side surface portion 5a2 is a portion on the downstream side in the conveyance direction of the tablet 5 in the side surface portion 5a1, and the upstream side surface portion 5a3 is a portion on the upstream side in the conveyance direction of the tablet 5 in the side surface portion 5a.

[0113] Further, the side surface region AR2 corresponding to the optical path conversion sheet 62b is a region composed of all regions of the downstream side surface portion 5a2 in the side surface portion 5a, a part of the left side surface portion 5a1, and a part of the right side surface portion 5a4 (see Figure 13 ). The right side surface portion 5a4 is a part on the other end side in the width direction of the adsorption belt 54 in the side surface portion 5a.

[0114] Further, the side surface region AR3 corresponding to the optical path conversion sheet 62c is a region composed of all regions of the right side surface portion 5a4 in the side surface portion 5a, a part of the downstream side surface portion 5a2, and a part of the upstream side surface portion 5a3 (see Figure 13 ).

[0115] Further, the side surface region AR4 corresponding to the optical path conversion sheet 62d is a region composed of all regions of the upstream side surface portion 5a3 in the side surface portion 5a, a part of the left side surface portion 5a1, and a part of the right side surface portion 5a4 (see Figure 13 ).

[0116] In addition, on the surface of the optical path conversion sheets 62a to 62d disposed on the side of the tablet 5, a plurality of protruding strip portions 62t are formed side by side in parallel. Further, the surface of the optical path conversion sheets 62a to 62d refers to the surface on which the protruding strip portions 62t are formed.

[0117] As Figure 14 shown, the protruding strip portion 62t is substantially right-angled triangular in a cross-section perpendicular to the extending direction of the protruding strip portion 62t, and has a substantially vertical surface 62t1 and an inclined surface 62t2. In addition, Figure 14 in the figure, for the sake of easy illustration, the hatching is omitted.

[0118] The substantially vertical surface 62t1 is the following surface, in the above cross-section, extends in a direction substantially perpendicular to the flat back surface 62r of the optical path conversion sheets 62a to 62d, and the angle α of the angle formed with respect to the back surface 62r is 80° or more and 95° or less.

[0119] The inclined surface 62t2 is the following surface, in the above cross-section, extends obliquely with respect to the back surface 62r, and the angle β of the angle formed with respect to the back surface 62r is 10° or more and 55° or less. Light is refracted on the inclined surface 62t2, so that the optical path of the light reflected from the side surface portion 5a is converted into an optical path along the optical axis OA. More specifically, the optical path of the light L1 ( Figure 14 shown by the thick dashed line in the figure) whose incident angle γ with respect to the inclined surface 62t2 is greater than the specified angle of the angle β is converted into an optical path along the optical axis OA. On the other hand, the optical paths of the light L2 and L3 whose incident angles with respect to the inclined surface 62t2 are the angle β or less are converted into optical paths inclined with respect to the optical axis OA, and are not converted into optical paths along the optical axis OA.

[0120] In addition, in the optical path conversion sheets 62a to 62d, the extending directions of the protruding strip portions 62t are each different by 90° (see Figure 12 . Figure 12 The extending direction of the protruding strip portion 62t shown by the arrow in the figure). Here, the extending direction of the protruding strip portion 62t means that when observing the surface of the optical path conversion sheets 62a to 62d (the surface where the protruding strip portion 62t exists) from the front (in this embodiment, when observing from the bottom surface), when advancing along the protruding strip portion 62t, the substantially vertical surface 62t1 related to the protruding strip portion 62t is on the right side, and the inclined surface 62t2 related to the protruding strip portion 62t is on the left side.

[0121] In this embodiment, the extending direction of the protruding strip portion 62t in the optical path conversion sheet 62a is parallel to the conveying direction of the tablet 5, and is in the opposite direction to the conveying direction.

[0122] In addition, the extending direction of the protruding strip portion 62t on the optical path conversion sheet 62b is perpendicular to the conveying direction of the tablet 5, and is a direction from the other end side in the width direction of the adsorption belt 54 toward the one end side in the width direction (i.e., a direction from the other end side row to the one end side row in the tablet 5).

[0123] Furthermore, the extending direction of the protruding strip portion 62t in the optical path conversion sheet 62c is parallel to the conveying direction of the tablet 5, and is the same direction as the conveying direction.

[0124] In addition, the extending direction of the protruding strip portion 62t in the optical path conversion sheet 62d is perpendicular to the conveying direction of the tablet 5, and is a direction from the one end side in the width direction of the adsorption belt 54 toward the other end side in the width direction (i.e., a direction from the one end side row to the other end side row in the tablet 5).

[0125] Moreover, in the present embodiment, while the light reflected at one side surface region AR1 of the tablet 5 located at a prescribed first position P1 (see Figure 15 、 Figure 16 ) is incident on the inclined surface 62t2 in the optical path conversion sheet 62a, the optical path conversion sheet 62a converts the optical path of the light reflected at the one side surface region AR1 into an optical path along the optical axis OA.

[0126] In addition, while the light reflected at one side surface region AR2 of the tablet 5 located at a prescribed second position P2 (see Figure 18 ) is incident on the inclined surface 62t2 in the optical path conversion sheet 62b, the optical path conversion sheet 62b converts the optical path of the light reflected at the one side surface region AR2 into an optical path along the optical axis OA.

[0127] Furthermore, while the light reflected at one side surface region AR3 of the tablet 5 located at a prescribed third position P3 (see Figure 20 、 Figure 21 ) is incident on the inclined surface 62t2 in the optical path conversion sheet 62c, the optical path conversion sheet 62c converts the optical path of the light reflected at the one side surface region AR3 into an optical path along the optical axis OA.

[0128] In addition, while the light reflected at one side surface region AR4 of the tablet 5 located at a prescribed fourth position P4 (see Figure 23 ) is incident on the inclined surface 62t2 in the optical path conversion sheet 62d, the optical path conversion sheet 62d converts the optical path of the light reflected at the one side surface region AR4 into an optical path along the optical axis OA.

[0129] Return to Figure 9 、 Figure 10, the object-side lens 63 is disposed between the camera 64 and the illumination device 61 and is configured to focus the light whose optical path is converted by the optical path conversion sheets 62a to 62d. In the present embodiment, the object-side lens 63 is composed of a Fresnel lens, which has sawtooth protrusions formed in a stepped and concentric shape on a specified resin thin plate material. Each protrusion functions as a refracting surface, enabling the object-side lens 63 to have the same function as an ordinary single lens.

[0130] The camera 64 is disposed on the side opposite to the surface of the tablet 5 adsorbed by the adsorption band 54 and is composed of at least a camera (such as a CCD camera or a CMOS camera, etc.) that is sensitive to the light irradiated from the illumination device 61. The camera 64 is equipped with an aperture 64a, an element-side lens 64b, and an imaging element 64c.

[0131] The aperture 64a is located between the object-side lens 63 and the element-side lens 64b and adjusts the light that forms an image on the light-receiving surface 64c1 of the imaging element 64c described later by restricting the amount of light entering the imaging element 64c from the object-side lens 63.

[0132] The element-side lens 64b converts the optical path of the light passing through the object-side lens 63 into a state parallel to the optical axis OA and the chief ray.

[0133] The imaging element 64c is composed of, for example, a CCD area sensor or a CMOS sensor, etc., and is configured to capture the light irradiated from the illumination device 61. The imaging element 64c has a light-receiving surface 64c1 in which a plurality of light-receiving elements are two-dimensionally arranged in a matrix, and the light-receiving surface 64c1 is set to be perpendicular to the optical axis OA. Through the shooting process by the camera 64, image data is acquired by the imaging element 64c. The acquired image data is sent to the image processing device 65.

[0134] In addition, in the present embodiment, an imaging optical system 66 is constituted by the object-side lens 63, the aperture 64a, and the element-side lens 64b, which is configured to image the light whose optical path is converted by the optical path conversion sheets 62a to 62d onto the imaging element 64c (light-receiving surface 64c1). The imaging optical system 66 is configured as an object-side telecentric optical system. That is, the imaging optical system 66 is configured such that, compared with the object-side lens 63, on the object side (tablet 5 side), the optical axis OA is parallel to the chief ray. In addition, the imaging optical system 66 in the present embodiment is also a bilateral telecentric optical system.

[0135] The image processing device 65 determines whether or not at least the side surface portion 5a of the tablet 5 is acceptable based on the image data obtained from the light imaged on the imaging element 64c (light receiving surface 64c1) (i.e., the image data obtained by the camera 64). The image processing device 65 is configured as a so-called computer system, which is equipped with: a CPU as an arithmetic unit, a ROM that stores various programs, a RAM that temporarily stores various data such as calculation data and input / output data, etc. The image processing device 65 is as Figure 7 shown, and is equipped with an image memory 65a, an inspection result storage device 65b, a determination memory 65c, an inspection condition storage device 65d, a camera timing control device 65e, and a CPU and an input / output interface 65f.

[0136] The image memory 65a is used to store the image data input from the camera 64. Based on the image data stored in this image memory 65a, an inspection related to whether or not the side surface portion 5a is acceptable is performed. Of course, when performing the inspection, the image data can be processed. For example, masking processing or shadow correction processing, etc. may be considered.

[0137] The inspection result memory 65b is used to store data on whether or not the acceptance determination result and statistical data obtained by performing probability statistical processing on this data, etc.

[0138] The determination memory 65c is used to store various information for inspection. Among the various information, it includes programs for determining the presence or absence of foreign matter, dirt, breakage (such as nicks, etc.), and various determination values as acceptance determination criteria, etc.

[0139] The inspection condition storage device 65d is used to store the date and time of non-acceptance determination, inspection conditions for inspection, etc.

[0140] The camera timing control device 65e is used to control the shooting timing of the camera 64. Specifically, the camera timing control device 65e controls the camera 64 in such a way that it takes pictures when the tablets 5 arranged in a row in the direction perpendicular to the conveying direction are at the first position P1, at the second position P2, at the third position P3, and at the fourth position P4, respectively.

[0141] In this embodiment, by photographing the tablet 5 at the first position P1, image data including a part related to one side surface area AR1 can be obtained (see Figure 17 : In addition, Figure 17 , Figure 19 , Figure 22 , Figure 24 only a part of the image data is shown). In addition, by photographing the tablet 5 at the second position P2, image data including a part related to one side surface area AR2 can be obtained (see Figure 19)。Furthermore, by photographing the tablet 5 located at the third position P3, image data including a part related to the one-side surface area AR3 can be obtained (see Figure 22 )。In addition, by photographing the tablet 5 located at the fourth position P4, image data including a part related to the one-side surface area AR4 can be obtained (see Figure 24 )。The four types of image data obtained in this way are image data respectively related to different one-side surface areas AR1, AR2, AR3, and AR4. Moreover, through these four types of image data, the entire outer peripheral part of the side surface part 5a of all the tablets 5 in one row amount can be covered.

[0142] In addition, the camera timing control device 65e controls the photographing timing of the camera 64 based on a signal sent by an encoder (not shown) provided on the tablet inspection filling device 21 for grasping the conveyance amount of the tablets 5.

[0143] The CPU and the input / output interface 65f have functions of inputting and outputting various types of data such as image data or pass / fail determination results, and functions of executing various types of programs. The CPU and the input / output interface 65f use the information stored in the determination-use memory 65c and the input image data to perform at least a pass / fail determination on the side surface part 5a of the tablet 5. In the present embodiment, a prescribed pass / fail determination process is performed on all the acquired image data, so that for each tablet 5, 4 types of image data are used to determine whether there are non-conforming parts in the entire outer periphery of the side surface part 5a. The pass / fail determination result is stored in the inspection result storage device 65b. In the present embodiment, it is inspected whether foreign matters or dirt are attached to the tablet 5, whether the tablet 5 has defects, etc.

[0144] As described above, according to the present embodiment, by being able to photograph multiple tablets 5 at one time for inspection, the structure of the device (camera 64) having the photographing element 64c and the tablet inspection device 23 itself is simplified, so that the miniaturization and simplification of the tablet inspection device 23 can be more reliably achieved. In addition, without arranging multiple devices (cameras 64) having the photographing element 64c, multiple tablets 5 can be photographed, thereby further realizing the miniaturization of the tablet inspection device 23. As a result, the tablet inspection device 23 can be designed to have a simple and compact structure.

[0145] In addition, the entire outer periphery of the side surface part 5a in the tablet 5 can be covered by the multiple one-side surface areas AR1 to AR4 corresponding to each of the optical path conversion sheets 62a to 62d. Therefore, the entire outer periphery of the side surface part 5a of the tablet 5 can be inspected.

[0146] In addition, even when changing the shape and size of the tablet 5 to be inspected, it is not necessarily necessary to replace or adjust the optical path conversion sheets 62a to 62d. Therefore, the convenience and efficiency related to inspection can be improved.

[0147] In addition, the influence of the light reflected from other parts of the tablet 5 on the part of the image data related to the one-side regions AR1 to AR4 can be suppressed, so that in the image data, the outlines and shapes of the part related to the one-side regions AR1 to AR4 and the defective parts (such as stains or defects) located in the one-side regions AR1 to AR4 become clearer. As a result, the presence or absence of defective parts in the side surface part 5a can be determined with high precision, and the positions of the defective parts can be specified more accurately and particularly.

[0148] In addition, through the aperture 64a, the light that has undergone optical path conversion by the optical path conversion sheets 62a to 62d and is imaged on the imaging element 64c can be adjusted. Therefore, on the basis of performing the inspection, appropriate image data can be obtained more reliably and easily.

[0149] In addition, since the object-side lens 63 is a Fresnel lens, the thickness of the object-side lens 63 can be designed to be relatively small. As a result, the tablet inspection device 23 can adopt a more compact structure.

[0150] In addition, since the optical path conversion sheets 62a to 62d have the above-described cross-sectional shapes, in each of the optical path conversion sheets 62a to 62d, the optical path of the light reflected at the corresponding one-side regions AR1 to AR4 is more reliably converted into an optical path along the optical axis OA direction of the imaging optical system 66. On the other hand, the situation where the optical path of the light reflected from other parts of the tablet 5 is converted into an optical path along the optical axis OA direction can be more effectively prevented. As a result, in the image data, the outlines and shapes of the part related to the one-side regions AR to AR4 or the defective parts can be made clearer more reliably. As a result, the presence or absence of defective parts in the side surface part 5a can be determined with higher precision, and the positions of the defective parts can be specified more accurately and particularly.

[0151] In addition, it is not limited to the description content of the above-described embodiment. For example, the following method can also be adopted. Of course, other application examples and modification examples not illustrated below are also possible.

[0152] (a) In the above-described embodiment, the illumination device 61 is arranged on the side opposite to the surface of the tablet 5 adsorbed by the adsorption belt 54. In contrast, as Figure 25 shown, the illumination device 61 can also be arranged on the same side as the surface of the tablet 5 adsorbed by the adsorption belt 54. Also, at this time, the adsorption belt 54 should be configured to be able to transmit the light irradiated by the illumination device 61.

[0153] (b) In the above-described embodiment, four optical path conversion sheets 62a to 62d are provided, but the number of optical path conversion sheets can be appropriately changed.

[0154] For example, as Figure 26As shown, three optical path conversion sheets 62e, 62f, and 62g can be set, and the entire outer periphery of the side portion 5a is covered by a plurality of one-side surface regions corresponding to the respective optical path conversion sheets 62e, 62f, and 62g. At this time, the extending directions of the respective rib portions 62t in the optical path conversion sheets 62e, 62f, and 62g can be set to differ by 120°.

[0155] Of course, it can also be configured to set two or five or more optical path conversion sheets, and the entire outer periphery of the side portion 5a is covered by a plurality of one-side surface regions corresponding to these optical path conversion sheets. In addition, in terms of improving the inspection accuracy, it is preferably set such that at least some of the one-side surface regions among the plurality of one-side surface regions overlap as in the above-described embodiment.

[0156] (c) In the above-described embodiment, each of the optical path conversion sheets 62a to 62d corresponds to one row of tablets 5, but it may also correspond to multiple rows of tablets 5. That is, it can be configured to simultaneously photograph multiple rows of tablets 5 through the respective optical path conversion sheets 62a to 62d.

[0157] (e) The illumination device 61 in the above-described embodiment has a light source 61a and a light guide plate 61b, but the structure of the illumination device can be appropriately changed. Therefore, for example, the light guide plate may not be provided, and the illumination device may be constituted by a plurality of light sources.

[0158] (f) As Figure 27 shown, a gap can be formed between adjacent optical path conversion sheets 62b and 62c, and the light reflected at one surface (the surface portion 5b or the back surface portion 5c) of the tablet 5 facing the imaging element 64c side is photographed through this gap. Moreover, based on the image data obtained from the light reflected at the surface of the tablet 5 facing the imaging element 64c side, the imaging processing device 65 can determine whether this surface is qualified. In this case, not only can the side portion 5a of the tablet 5 be inspected, but also the surface portion 5b or the back surface portion 5c of the tablet 5 can be inspected. Therefore, the inspection efficiency of the tablet � can be further improved.

[0159] (f) As Figure 28 shown, the illumination device 61 can be configured to be constituted by the light source 61a, and the illumination device 61 (light source 61a) is arranged between the plurality of optical path conversion sheets 62a to 62d. In this case, since the illumination device 61 can be housed between the optical path conversion sheets 62a to 62d, the miniaturization of the tablet inspection device 23 can be further achieved.

[0160] (g) In the above-described embodiment, the surface (the surface on which the rib portion 62t is formed) of the optical path conversion sheets 62a to +02d is provided on one side of the tablet 5. In contrast, as Figure 29As shown, the surfaces of the optical path conversion sheets 62a to 62d can be configured to be on the opposite side of the tablet 5, that is, on the side of the camera 64 (imaging element 64c).

[0161] (h) In the above-described embodiment, the tablet inspection device 23 (particularly, the optical path conversion sheets 62a to 62d, the object-side lens 63, and the camera 64) is disposed on the side opposite to the surface (adsorbed surface) of the tablet 5 that is adsorbed by the adsorption belt 54. On the contrary, the tablet inspection device 23 can also be disposed on the adsorbed surface side of the tablet 5. For example, the tablet inspection device 23 can be disposed in the space surrounded by the adsorption belt 54. In addition, in this case, the adsorption belt 54 should be designed to be able to transmit the light irradiated by the illumination device 61.

[0162] (i) In the above-described embodiment, the one-side surface regions AR1 to AR4 corresponding to the respective optical path conversion sheets 62a to 62d are configured to be photographed at different timings. However, the photographing timings of at least two of the plurality of one-side surface regions can be made the same. Therefore, for example, it can be configured such that the two one-side surface regions AR1 and AR4 are photographed at the same timing. Of course, it can also be configured such that all of the one-side surface regions AR1 to AR4 are photographed at the same timing.

[0163] In addition, in the above-described embodiment, the image data related to all regions of the one-side surface region is acquired by one photographing, but it can also be acquired by multiple photographings.

[0164] (j) In the above-described embodiment, the tablet 5 is circular when viewed from above, but the tablet 5 can also be oblong or oval when viewed from above, etc.

[0165] (k) The tablet is not limited to a pharmaceutical tablet, and can also be a dietary tablet, etc. In addition, the tablet includes not only plain tablets, but also sugar-coated tablets, coated tablets, chewable tablets in the mouth, enteric-coated tablets, gelatin-coated tablets, etc. Of course, it also includes various capsule tablets such as hard capsules and soft capsules.

[0166] (l) In the above-described embodiment, the tablets 5 are transported in a state of being arranged in 5 columns, but the number of columns of the transported tablets 5 can be multiple and is not limited to 5 columns.

[0167] (m) In the above-described embodiment, the tablet inspection device 23 is configured to inspect the tablets 5 before they are filled into the bag portion 2. In contrast, as Figure 30 Note: In the translation of , "~" is translated as "-". If there are more specific requirements for this symbol, please adjust accordingly. shown, the tablet inspection device 23 can also be arranged downstream of the tablet filling device 22 along the transport path of the container film 3, and the tablets 5 filled into the bag portion 2 are inspected by the tablet inspection device 23.

[0168] [Description of reference symbols]

[0169] 5…Tablet, 5a…Side face portion, 5b…Surface portion, 5c…Back face portion, 23…Tablet inspection device, 61…Illumination device (irradiation mechanism), 62a, 62b, 62c, 62d…Optical path conversion sheets, 62r…Back surface (of the optical path conversion sheet), 62t…Ridge portion, 62t1…Substantially vertical plane, 62t2…Inclined plane, 63…Object-side lens, 64c…Imaging element, 65…Image processing device (judgment mechanism), 66…Imaging optical system, AR1, AR2, AR3, AR4…One side area, OA…Optical axis.

Claims

1. A tablet inspection device for inspecting the side faces of a plurality of tablets transported in a side-by-side state in multiple columns, characterized in that, The tablet inspection device includes: An irradiation mechanism that irradiates prescribed light onto a plurality of tablets; An imaging element that is used to capture the light irradiated from the irradiation mechanism; An optical path conversion sheet that can convert the optical path of the light irradiated from the irradiation mechanism and reflected at a circumferentially continuous side surface area in the side surface portion; An imaging optical system that images the light whose optical path has been converted by the optical path conversion sheet onto the imaging element, and A determination mechanism that can determine whether the side surface portion is qualified based on the image data obtained from the light imaged on the imaging element; The optical path conversion sheet is configured such that, when viewed from the imaging element side, it straddles multiple columns of the tablet, and a plurality of the optical path conversion sheets are arranged along the tablet conveyance direction; The plurality of optical path conversion sheets respectively correspond to different ones of the side surface areas, and are configured to convert the optical path of the light reflected at the corresponding side surface area into an optical path along the optical axis direction of the imaging optical system; It is further configured such that the entire outer periphery of the side surface portion is covered by the plurality of side surface areas corresponding to the respective optical path conversion sheets.

2. The tablet inspection device according to claim 1, wherein The imaging optical system is configured to form an object-side telecentric optical system and has an aperture that can adjust the light imaged on the imaging element.

3. The tablet inspection device according to claim 1, characterized in that, The imaging optical system has an object-side lens that is used to focus the light whose optical path has been converted by the optical path conversion sheet; The object-side lens is a Fresnel lens.

4. The tablet inspection device according to claim 1, characterized in that, A plurality of ridge portions are formed in parallel side by side on the surface of the optical path conversion sheet; The ridge portion has: A basic vertical surface, the angle of the angle formed by the basic vertical surface relative to the flat back surface of the optical path conversion sheet in a cross section perpendicular to the extending direction of the ridge portion is 80° or more and 95° or less; and An inclined surface, in the cross section, the angle of the angle formed by the inclined surface relative to the back surface is 10° or more and 55° or less.

5. The tablet inspection device according to claim 1, characterized in that, The irradiation mechanism is disposed between the plurality of optical path conversion sheets.

6. The tablet inspection device according to claim 1, characterized in that, The imaging optical system is configured to be able to image the light that passes between the plurality of optical path conversion sheets and is reflected at the surface of the tablet facing the imaging element side onto the imaging element; The determination mechanism can determine whether the surface of the tablet facing the imaging element side is qualified based on the image data.

Images