Article inspection device

Abstract

To provide an article inspection device capable of preventing deterioration in inspection accuracy.SOLUTION: The article inspection device includes: a conveying disk 11 that conveys a tablet W; a light source portion 3 that irradiates the tablet W being conveyed with light from a projection end 3a; a light-detecting portion 4 that has an incident end 4a on which transmitted light emitted from the light source portion 3 and transmitted through the tablet W is incident and detects the transmitted light incident through the incident end 4a; an inspection portion 21 that inspects the tablet W on the basis of the transmitted light detected by the light-detecting portion 4; a light quantity determination portion 22 that determines whether or not a light quantity of reference light emitted from the light source portion 3 and detected by the light-detecting portion 4 without being transmitted through the tablet W is lower than a reference light quantity by a predetermined value or more; and cleaning portions 23 and 24 that clean the projection end 3a and the incident end 4a when the light quantity determination portion 22 determines that the light quantity of the reference light is lower than the reference light quantity by the predetermined value or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an article inspection device. [Background technology]

[0002] Patent Document 1 discloses an inspection device that includes a light source and a sensor that is a light-receiving element, which are arranged facing each other along the vertical direction, which is the direction of the rotation axis of a rotor that transports the molded product, sandwiching the molded product and the rotor.The light or electromagnetic waves emitted from the light source that have passed through the molded product are made incident on the sensor as signal light, and the signal light is analyzed to inspect whether the molded product contains any foreign matter and / or whether the components and other qualities of the molded product are appropriate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-112199 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the inspection device described in Patent Document 1, if dust or the like adheres to the light source or the sensor, which is the light receiving element, and the light source or sensor becomes dirty, the amount of light from the light source will decrease, or the amount of light received by the sensor will decrease.

[0005] If the amount of light from the light source or the amount of light received by the sensor decreases, the accuracy of the inspection may decrease.

[0006] The present invention has been made in view of the above circumstances, and has as its object to provide an article inspection device that can prevent a decrease in inspection accuracy. [Means for solving the problem]

[0007] The object inspection device of the present invention comprises a conveying section (11) that conveys an object (W) to be inspected, a light source section (3) that irradiates the object (W) from a light-emitting end (3a) while being conveyed, a light detection section (4) that has an incident end (4a) into which transmitted light irradiated from the light source section and transmitted through the object is incident and detects the transmitted light incident through the incident end, an inspection section (21) that inspects the object based on the transmitted light detected by the light detection section, a light intensity determination section (22) that determines whether the light intensity of the irradiated light irradiated from the light source section and detected by the light detection section without transmitting through the object is lower than a reference light intensity by a predetermined value or more, and cleaning sections (23, 24) that clean at least one of the light-emitting end and the incident end when the light intensity determination section determines that the light intensity of the irradiated light is lower than the reference light intensity by a predetermined value or more.

[0008] With this configuration, the article inspection device according to the present invention includes a cleaning unit that cleans at least one of the light-emitting end and the light-incident end when it is determined that the amount of irradiated light emitted from the light source unit and detected by the light-detector unit without passing through the article is lower than the reference light amount by a predetermined value or more, so that it is possible to detect that at least one of the light-emitting end of the light source unit or the light-incident end of the light-detector unit has become dirty and perform cleaning. This prevents a decrease in the amount of light detected by the light-detector unit, and as a result, prevents a decrease in inspection accuracy.

[0009] In the item inspection device of the present invention, the cleaning unit is configured to repeatedly perform the cleaning until the difference between the light intensity of the irradiated light and the reference light intensity becomes less than the predetermined value, and it is preferable that the inspection of the item is stopped if the difference between the light intensity of the irradiated light and the reference light intensity does not become less than the predetermined value even after performing the cleaning a predetermined number of times.

[0010] With this configuration, the article inspection device of the present invention repeats cleaning until the difference between the light intensity of the irradiated light and the reference light intensity becomes less than a predetermined value, so cleaning can be continued until dirt is removed from either the light-emitting end of the light source unit or the light-incident end of the light-detecting unit, or both. Furthermore, if the difference between the light intensity of the irradiated light and the reference light intensity does not become less than a predetermined value even after performing cleaning a predetermined number of times, article inspection is stopped, so unnecessary repeated cleaning can be prevented, and further, stopping article inspection can prompt the user to perform appropriate processing other than cleaning by the cleaning unit.

[0011] In the article inspection device according to the present invention, it is preferable that the light detection unit has a spectroscope (42) that measures the spectral characteristics of the transmitted light, and that the light detection unit reduces the gain of the spectroscope when detecting the irradiated light compared to when detecting the transmitted light.

[0012] With this configuration, the item inspection device of the present invention reduces the gain of the spectrometer when detecting illuminated light compared to when detecting transmitted light, so that the gain of the spectrometer can be switched to an optimal gain suited to each situation when detecting illuminated light to determine whether or not the light intensity has decreased using the light intensity determination unit, and when detecting transmitted light to inspect the item.

[0013] In the article inspection device according to the present invention, the cleaning unit may be configured by an air injection unit (23, 24) that blows air onto at least one of the light-emitting end and the light-incident end.

[0014] With this configuration, the object inspection device of the present invention has a cleaning section that is composed of an air injection section that blows air onto at least one of the light-emitting end and the incident end, so that dust and the like that has adhered to the light-emitting end or the incident end, or both, can be removed without contact. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide an article inspection device that can prevent a decrease in inspection accuracy. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram of an article inspection device according to one embodiment of the present invention. [Figure 2] FIG. 2 is a flowchart showing the flow of cleaning control processing executed in an article inspection device according to one embodiment of the present invention. [Figure 3] FIG. 3 is a schematic diagram showing a modified example of the cleaning unit of an article inspection device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an article inspection device according to an embodiment of the present invention will be described with reference to the drawings.

[0018] In this embodiment, as an example of an item inspection device that irradiates light onto an item to be inspected, detects the transmitted light that has passed through the item, and inspects the item based on the detected transmitted light, we will describe an item inspection device 10 that, when an item to be inspected is transported individually along a transport path by a transport unit and reaches a predetermined inspection position, irradiates light onto the item, which is in a fixed position at the predetermined inspection position, and inspects the quality of the item based on the spectral characteristics of the transmitted light that has passed through the item as a result of the irradiation of this light.

[0019] The object inspection device of this embodiment may be, for example, an object inspection device that irradiates an object to be inspected with visible light, infrared light, etc., detects the transmitted light that passes through the object, and inspects the object based on a transmitted image obtained from the detected transmitted light.

[0020] The items to be inspected are items that are relatively close in size to the area irradiated with light, and include items with an outer diameter φ of several mm to several tens of mm that can be transported individually without packaging, bite-sized items, as well as items and molded products of a predetermined shape manufactured using existing manufacturing equipment or manufacturing equipment without inspection functions, and especially items that do not change shape during transportation.

[0021] Examples of such articles include pharmaceutical preparations such as tablets, capsules, lozenges, and drops, as well as candy and chocolate. The following description will be given taking as an example an article to be inspected a tablet W that is circular in plan view, has a height (thickness) smaller than its diameter, and is roughly cylindrical in side view. Note that the article to be inspected is not limited to a circular shape in plan view, and articles of various shapes such as an oval shape or a polygonal shape can also be used.

[0022] The conveying unit may be, for example, a conveying unit configured to align and convey articles individually, such as a conveying belt, a conveying disk, or a conveying chute. In this embodiment, an example will be described in which a conveying disk 11 (see FIG. 1) is used as the conveying unit.

[0023] As shown in Fig. 1, the conveying disk 11 is a conveying unit configured to suck tablets W into suction holes on its outer circumferential surface and convey them in the circumferential direction while rotating horizontally. In the conveying disk 11, the tablets W are conveyed with their upper and lower surfaces kept horizontal as their sides are sucked into the suction holes. Fig. 1 shows only a portion of the outer circumferential side of the conveying disk 11. The conveying disk 11 is driven to rotate by a drive motor 12.

[0024] The article inspection device 10 according to this embodiment includes a spectroscopic measurement device 1 and a control device 2.

[0025] [Spectrometer] The spectroscopic measurement device 1 includes a light source unit 3 and a light detection unit 4. The spectroscopic measurement device 1 irradiates a tablet W to be measured with broadband light (visible light, near-infrared to terahertz light (terahertz waves)), and measures the spectral characteristics of the light that passes through the tablet W in response to the irradiation of this light.

[0026] (Light source part) The light source unit 3 is configured to irradiate a tablet W passing through a predetermined inspection position, i.e., a tablet W being conveyed (moving), with broadband light from a light-emitting end 3a, which will be described later. In this embodiment, the light source unit 3 is arranged on the opposite side (lower side in this embodiment) from the light detection unit 4 across the conveyance path of the tablet W, so as to irradiate light from one side (lower side in this embodiment) of a pair of circular end faces of the approximately cylindrical tablet W to the other side (upper side in this embodiment).

[0027] The conveying path of the tablet W is an area through which the tablet W passes during conveyance. The predetermined inspection position is a position on the conveying path of the tablet W where the light source unit 3 and the light detection unit 4 are arranged.

[0028] The light source unit 3 includes a light source 30 , a light guide 31 , and an optical lens 32 .

[0029] The light source 30 is composed of a broadband light source, such as a halogen lamp, in order to irradiate broadband light onto the tablet W to be measured, and is provided at a predetermined position as a light source unit integrally assembled with a lamp holding means (not shown) and a case having heat dissipation fins, and is connected to a power supply unit (neither of which is shown).

[0030] Broadband light refers to visible light and near-infrared to terahertz light (light including terahertz waves). The wavelength of the irradiated light does not need to cover all of these; for example, a wavelength band of 400-2500 nm can easily penetrate a measured object such as a tablet and is less likely to be damaged by ultraviolet light, so it may be limited to this wavelength band or the near-infrared band within this wavelength band. Furthermore, if the absorption spectrum of the component to be measured is known, only the wavelength band corresponding to the absorption spectrum may be used.

[0031] The light guide 31 is made up of a number of glass optical fibers bundled together, and guides the light from the light source 30 to an optical lens 32 that condenses the light.

[0032] The optical lens 32 focuses light from the light guide 31 onto the tablet W at a predetermined inspection position (the lower surface of the tablet W in the example of FIG. 1). In this embodiment, the end of the optical lens 32 facing the tablet W (the upper end in this embodiment) constitutes the light-emitting end 3a of the light source unit 3.

[0033] The light source unit 3 may have a dustproof cover glass provided between the optical lens 32 and the tablet W. In this case, the upper surface of the cover glass constitutes the light-emitting end 3a of the light source unit 3.

[0034] The light source unit 3 emits broadband light from the light source 30 to the optical lens 32 via the light guide 31, and adjusts the magnification of the optical lens 32 (the positions of the optical lens 32, light source 30 and tablet W) so that the optical lens 32 covers the entire underside of the tablet W at the specified inspection position, thereby efficiently irradiating the light from the light source 30 onto the tablet W passing through the specified inspection position.

[0035] (Photodetector) The light detection unit 4 includes an optical fiber 41 and a spectroscope .

[0036] The light detection unit 4 is positioned on the opposite side (in this embodiment, the upper side) from the light source unit 3 across the conveying path of the tablet W, so as to face the other (in this embodiment, the upper side) of a pair of circular end faces of the approximately cylindrical tablet W.

[0037] The optical fiber 41 is connected to the spectroscope 42, and the end on the opposite side to the spectroscope 42 (the side facing the tablet W) is configured as the incident end 4a of the light detection unit 4.

[0038] The light detecting unit 4 may have a dustproof cover glass provided between the optical fiber 41 and the tablet W. In this case, the lower surface of the cover glass constitutes the incident end 4a of the light detecting unit 4.

[0039] The optical fiber 41 is configured so that transmitted light that has passed through the tablet W at a predetermined inspection position is incident through the incident end 4a. The transmitted light that has passed through the tablet W enters the optical fiber 41 from the incident end 4a. The transmitted light that has entered the optical fiber 41 passes through the optical fiber 41 and reaches the spectroscope 42.

[0040] The spectroscope 42 performs spectrometry using, for example, a grating that utilizes differences in the diffraction angle depending on the wavelength of light. Specifically, the light that enters the spectroscope 42 is irradiated onto a grating (diffraction grating) and separated into individual wavelength components. The light separated into individual wavelength components is then detected for each wavelength component by a row of photodetector elements. The light intensity for each wavelength component is then measured. The grating is an optical element with multiple grooves engraved on its surface.

[0041] A tapered optical fiber with a large input diameter and a small output diameter can be used as the optical fiber 41. This allows the transmitted light to be incident on the spectroscope 42 more efficiently.

[0042] In this way, the light detection unit 4 receives light irradiated from the light source unit 3 and transmitted through the tablet W, and the transmitted light is incident on the optical fiber 41, and the spectrometer 42 measures the spectral characteristics of the transmitted light that has passed through the optical fiber 41.

[0043] [Control device] The control device 2 is configured by a computer unit that includes at least a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an input port, and an output port.

[0044] The control device 2 is connected to various sensors such as a tablet detection sensor that detects the tablets W being conveyed, as well as a drive motor 12 and an operation display unit 20. The drive of the drive motor 12 is controlled by the control device 2.

[0045] The operation display unit 20 is configured by, for example, a touch panel display. The operation display unit 20 has a function as a display unit that displays various information in addition to a viewer display screen related to the management of each tablet W, and also has a function as an operation unit that accepts various operations such as adjustment operations from the user. Examples of user operations include various setting operations, driving operations, and selection operations.

[0046] The control device 2 has a function as an inspection unit 21 that inspects the tablets W based on the transmitted light of the tablets W detected by the light detection unit 4.

[0047] The inspection unit 21 has a signal processing unit (not shown) that processes the spectroscopic characteristics obtained by the light detection unit 4 within a predetermined exposure time, and inspects the quality of the tablet W, i.e., determines whether the quality of the tablet W is good or bad, based on the results of the signal processing.

[0048] The signal processing unit calculates the spectral characteristics of the absorbance absorbed by the tablet W from the spectral characteristics obtained by the light detection unit 4. Specifically, the absorbance A at wavelength λ is obtained by the formula A=-log10(I / Ii), which is the common logarithm of the ratio (transmittance) of the light intensity Ii of the incident light to the light intensity I of the transmitted light, and the transmitted amount detected when there is no tablet W at the predetermined inspection position can be calculated as the light intensity Ii of the incident light.

[0049] The inspection unit 21 compares the spectroscopic characteristics of absorbance of a non-defective tablet W obtained in advance (intensity of each wavelength of the spectrum (including when differentiated multiple times), waveform shape, information obtained by extracting the entire or partial region and creating a calibration curve, statistical information) with the spectroscopic characteristics of absorbance of the tablet W to be inspected that has been transported to a predetermined inspection position, and judges whether the quality of the tablet W is good or bad based on the magnitude of the difference. The inspection unit 21 outputs a sorting signal based on the pass / fail result of the judgment to a sorting unit (not shown) that sorts the tablets W into normal and defective products.

[0050] Specifically, for example, the quality of the tablet W is judged based on whether the difference amount for each wavelength determined by calculation using a calibration curve obtained by statistical calculation results (such as standard deviation) or statistical methods such as regression is within a predetermined range (a range determined based on the results of statistical calculations or the results of the calibration curve).The quality of the tablet W can also be judged based on whether the sum of the intensities of each wavelength is within a predetermined range.Furthermore, if the components of the tablet W are uniform, the quality of the tablet W may be judged based on whether there is an intensity exceeding a predetermined threshold value set in advance in a region other than the specific wavelength.

[0051] The control device 2 has a function as a light amount determination unit 22. The light amount determination unit 22 determines whether or not the amount of irradiated light (also referred to as reference light) that is irradiated from the light source unit 3 and detected by the light detection unit 4 without passing through the tablet W is lower than the reference light amount by a predetermined value or more.

[0052] The reference light refers to the light that is irradiated from the light source unit 3 and directly incident on the light detection unit 4 when there is no tablet W at the predetermined inspection position. The reference light amount is the amount of reference light that is irradiated from the light source unit 3 and detected by the light detection unit 4 when the light projection end 3a and the incident end 4a are not dirty, such as when the article inspection device 10 is installed or after cleaning the light projection end 3a of the light source unit 3 and the incident end 4a of the light detection unit 4, and is measured in advance and stored in the ROM of the control device 2.

[0053] The predetermined value is the lower limit of the difference between the light amount at which it is determined that the accuracy of the inspection by the inspection unit 21 has deteriorated to an unacceptable level and the reference light amount, and is experimentally determined in advance and stored in the ROM of the control device 2.

[0054] Here, cleaning units 23 and 24 are connected to the control device 2. The cleaning units 23 and 24 are configured by air injection units including air nozzles 23a and 24a that inject air, respectively, and air compressors (not shown) that supply compressed air to the air nozzles 23a and 24a. The air compressor may be the same for the air nozzles 23a and 24a, or different air compressors may be used.

[0055] The cleaning unit 23 is provided to clean the light emitting end 3a of the light source unit 3, and has an air nozzle 23a disposed radially outside the conveying disk 11 relative to the conveying path of the tablets W.

[0056] The cleaning unit 23 is configured to blow compressed air from the air nozzle 23 a onto the light-emitting end 3 a of the light source unit 3 when the compressor is driven by an instruction from the control device 2 .

[0057] The cleaning unit 24 is provided to clean the incident end 4a of the light detection unit 4, and has an air nozzle 24a disposed radially outside the transfer disk 11 relative to the transfer path of the tablet W.

[0058] The cleaning unit 24 is configured so that the compressor is driven by an instruction from the control device 2, and compressed air is blown from the air nozzle 24a onto the incident end 4a of the light detection unit 4.

[0059] The arrangement of the air nozzles 23a and 24a described above is an example and is not limited to this, and any arrangement may be used as long as it does not interfere with the transport of the tablet W and is capable of blowing air onto the light-emitting end 3a and the light-incident end 4a.

[0060] When the control device 2 determines that the light intensity of the reference light is lower than the standard light intensity by a predetermined value or more, it controls the cleaning units 23 and 24 to spray air toward the light-emitting end 3a and the incident end 4a, respectively, thereby cleaning the light-emitting end 3a and the incident end 4a.

[0061] [About cleaning control] Next, a process flow of cleaning control executed by the control device 2 will be described with reference to Fig. 2. This cleaning control is repeatedly executed at predetermined time intervals.

[0062] 2, the control device 2 determines whether it is the measurement timing to measure the reference light while the article inspection device 10 is in operation (step S1). Specifically, the control device 2 determines whether it is the timing when there are no tablets W at a predetermined inspection position based on the detection result of the tablet detection sensor. The measurement timing can be set at any interval, and may be set, for example, for all tablets that are conveyed sequentially, or may be set at a certain time interval, such as every time a predetermined number of tablets are detected.

[0063] If the control device 2 determines in step S1 that it is not time to measure, it ends this cleaning control.

[0064] When the control device 2 determines in step S1 that it is time to measure, it switches the gain of the spectroscope 42 from large to small (step S2). When measuring tablet W, the light incident on the optical fiber 41 becomes transmitted light that has passed through tablet W, so the light intensity for each wavelength detected by the spectroscope 42 decreases. Therefore, when measuring tablet W, the gain of the spectroscope 42 is increased to amplify the signal corresponding to the detected light intensity. In contrast, at the above-mentioned measurement timing, the light incident on the optical fiber 41 is reference light, so the light intensity for each wavelength detected by the spectroscope 42 increases compared to when measuring tablet W. Therefore, at the above-mentioned measurement timing, the gain of the spectroscope 42 is reduced. Here, the aforementioned "reducing the gain" includes shortening the exposure time of the spectroscope 42.

[0065] Next, the control device 2 measures the reference light (step S3) and determines whether or not cleaning of the light-emitting end 3a of the light source unit 3 and the incident end 4a of the light detection unit 4 is necessary (step S4). Specifically, the control device 2 determines whether or not the light intensity of the reference light that is irradiated from the light source unit 3 and detected by the light detection unit 4 without passing through the tablet W is lower than the standard light intensity by a predetermined value or more.

[0066] If the control device 2 determines in step S4 that cleaning of the light-emitting end 3a and the incident end 4a is not necessary, i.e., if it determines that the light intensity of the reference light is not lower than the standard light intensity by more than a predetermined value, it switches the gain of the spectrometer 42 from small to large, i.e., returns the gain of the spectrometer 42 to the value at the time of measuring the tablet W (step S5), and terminates this cleaning control.

[0067] If the control device 2 determines in step S4 that cleaning of the light-emitting end 3a and the light-incident end 4a is necessary, i.e., if it determines that the light intensity of the reference light is lower than the standard light intensity by a predetermined value or more, it controls the drive motor 12 to stop the rotation of the conveying disk 11 and stop the conveyance of the tablet W (step S6).

[0068] At this time, the control device 2 controls the drive motor 12 so that the tablet W does not stop at a predetermined inspection position, i.e., above the light source unit 3. This prevents air from hitting the tablet W or blowing the tablet W away when cleaning the light-emitting end 3a and the light-incident end 4a. It also prevents the tablet W from reducing the light intensity of the reference light measured in step S8 to determine whether re-cleaning, which will be described later, is necessary.

[0069] Next, the control device 2 cleans the light-emitting end 3a and the incident end 4a (step S7). Specifically, the control device 2 controls the cleaning units 23 and 24 to blow air onto the light-emitting end 3a and the incident end 4a.

[0070] Thereafter, the control device 2 measures the reference light (step S8) and determines whether or not re-cleaning of the light-emitting end 3a and the light-incident end 4a is necessary (step S9). Specifically, the control device 2 determines whether or not the difference between the light intensity of the reference light measured in step S8 and the standard light intensity is less than the predetermined value.

[0071] In the determination in step S9, it may be determined whether re-cleaning is necessary by determining whether the difference between the light intensity of the reference light measured in step S8 and the standard light intensity is equal to or less than a re-cleaning determination threshold that is smaller than the predetermined value. In this case, the re-cleaning determination threshold has a margin with respect to the predetermined value, so that it is possible to suppress hunting in control, such as repeated restart of conveyance and cleaning.

[0072] If the control device 2 determines in step S9 that re-cleaning of the light-emitting end 3a and the light-incident end 4a is not necessary, i.e., if it determines that the difference between the light intensity of the reference light measured in step S8 and the standard light intensity is less than the above-mentioned predetermined value, it resumes the transportation of the tablet W that was stopped in step S6 (step S10) and moves the processing to step S5.

[0073] If the control device 2 determines in step S9 that re-cleaning of the light-emitting end 3 a and the light-incident end 4 a is necessary, that is, if the control device 2 determines that the difference between the light intensity of the reference light measured in step S8 and the standard light intensity is not less than the predetermined value, the control device 2 determines whether the cleaning in step S7 has been performed a predetermined number of times (step S11). The predetermined number of times can be set to any number of times, and can be set to the minimum number of times that can restore the light intensity, for example, unless special dirt that cannot be removed by air blowing has occurred.

[0074] If the control device 2 determines in step S11 that the cleaning in step S7 has not been performed the predetermined number of times, it returns the process to step S7 and performs cleaning again.

[0075] When the control device 2 determines in step S11 that the cleaning in step S7 has been performed a predetermined number of times, it executes an error stop process (step S12) and ends this cleaning control. As the error stop process, the control device 2 stops the operation of the article inspection device 10, i.e., stops the inspection of the tablets W, and notifies the outside that an error has occurred.

[0076] [Action and effect] As described above, the article inspection device according to this embodiment is equipped with cleaning units 23, 24 that clean the light-emitting end 3a and the incident end 4a when it is determined that the light intensity of the reference light irradiated from the light source unit 3 and detected by the light detection unit 4 without passing through the tablet W is lower than the reference light intensity by a predetermined value or more, so that it is possible to detect that the light-emitting end 3a of the light source unit 3 or the incident end 4a of the light detection unit 4, or both, are dirty and perform cleaning. This makes it possible to prevent a decrease in the light intensity detected by the light detection unit 4, and as a result, to prevent a decrease in inspection accuracy.

[0077] The object inspection device of this embodiment repeatedly performs cleaning until the difference between the light intensity of the reference light and the standard light intensity becomes less than a predetermined value, so cleaning can be performed until dirt is removed from either the light-emitting end 3a of the light source unit 3 or the incident end 4a of the light detection unit 4, or both.

[0078] Furthermore, if the difference between the light intensity of the reference light and the standard light intensity does not become less than a predetermined value even after cleaning is performed a predetermined number of times, the inspection of the tablets W is stopped, thereby preventing unnecessary repetition of cleaning, and furthermore, by stopping the inspection of the tablets W, the user can be prompted to perform appropriate processing other than cleaning by the cleaning units 23 and 24.

[0079] In the object inspection device of this embodiment, the gain of the spectrometer 42 is made smaller when detecting reference light than when detecting transmitted light, so that the gain of the spectrometer 42 can be switched to an optimal gain suited to each situation when detecting reference light to determine whether or not the light intensity has decreased using the light intensity determination unit 22, and when detecting transmitted light to inspect the tablet W.

[0080] In the object inspection device of this embodiment, the cleaning units 23 and 24 are configured as air injection units that blow air onto the light-emitting end 3a and the incident end 4a, so that dust and the like adhering to the light-emitting end 3a, the incident end 4a, or both, can be removed without contact.

[0081] [Variations] In this embodiment, the cleaning units 23 and 24 are configured as air injection units, but this is not limiting. The cleaning units 23 and 24 may be configured to physically come into contact with the light-emitting end 3 a and the light-incident end 4 a to perform cleaning, for example, as shown in FIG. 3, they may be configured as a brush mechanism equipped with brushes 123 a and 124 a and actuators 123 b and 124 b.

[0082] The actuators 123b and 124b are connected to the control device 2, and rotate the brushes 123a and 124a around their axes in accordance with instructions from the control device 2, bringing them into contact with the light-emitting end 3a and the incident end 4a to clean the light-emitting end 3a and the incident end 4a. At this time, a mechanism is further provided for moving the brushes 123a and 124a along the light-emitting end 3a and the incident end 4a.

[0083] Further, the brushes 123a and 124a may be bristle-shaped and may be moved along the light-emitting end 3a and the light-incident end 4a while being in contact with the latter.

[0084] Furthermore, in this embodiment, the cleaning units 23 and 24 are configured to blow air, but this is not limited thereto. The cleaning units 23 and 24 may be configured to include a suction nozzle and a suction pump that generates negative pressure, and to suck up dust and the like adhering to the light-emitting end 3 a and the light-incident end 4 a.

[0085] Furthermore, in this embodiment, a configuration in which the cleaning units 23, 24 are provided at both the light-emitting end 3a and the incident end 4a has been described, but this is not limiting, and a configuration in which a cleaning unit is provided only at either the light-emitting end 3a or the incident end 4a may also be used. For example, the cleaning unit 23 is provided only at the light-emitting end 3a, which is prone to attracting dust and the like.

[0086] Furthermore, in this embodiment, a configuration has been described in which, when the control device 2 determines that cleaning of the light-emitting end 3a and the incident end 4a is necessary, the transport of the tablets W is stopped and the cleaning is performed, but this is not limited to this, and for example, the configuration may be such that the cleaning is performed at a time when the tablets W are not being transported without stopping the transport of the tablets W.

[0087] Furthermore, in this embodiment, a configuration has been described in which inspection of the tablet W is stopped if the difference between the light intensity of the reference light and the standard light intensity does not become less than a predetermined value even after cleaning has been performed a predetermined number of times. However, the present invention is not limited to this, and for example, a configuration may be adopted in which an alert is issued to warn of a decrease in light intensity if the difference between the light intensity of the reference light and the standard light intensity does not become less than a predetermined value even after cleaning has been performed a predetermined number of times.

[0088] While an embodiment of the present invention has been disclosed, it will be apparent to one skilled in the art that modifications may be made thereto without departing from the scope of the present invention, and it is intended that all such modifications and equivalents be included in the following claims. [Explanation of symbols]

[0089] 1 Spectrometer 2. Control device 3 Light source section 3a Light emitting end 4. Light detection unit 4a Incidence end 10. Item inspection equipment 11 Transfer disk (transfer section) 12 Drive motor 20 Operation display section 21 Inspection Department 22 Light intensity determination section 23, 24 Cleaning section (air injection section) 23a, 24a Air nozzle 30 light source 31 Light Guide 32 Optical Lenses 41 Optical Fiber 42 Spectrometer 123a, 124a brush 123b, 124b Actuators W Tablet (item)

Claims

1. a conveying section (11) for conveying an object (W) to be inspected; a light source unit (3) that irradiates light from a light projection end (3a) onto the article being conveyed; a light detection unit (4) having an incident end (4a) into which transmitted light irradiated from the light source unit and transmitted through the object is incident, the light detection unit detecting the transmitted light incident through the incident end; an inspection unit (21) that inspects the article based on the transmitted light detected by the light detection unit; a light amount determination unit (22) that determines whether the amount of irradiated light that is irradiated from the light source unit and detected by the light detection unit without passing through the object is lower than a reference light amount by a predetermined value or more; An object inspection device comprising a cleaning unit (23, 24) that cleans at least one of the light-emitting end and the incident end when the light intensity determination unit determines that the light intensity of the irradiated light is lower than the reference light intensity by a predetermined value or more.

2. The object inspection device of claim 1, wherein the cleaning unit is configured to repeatedly perform the cleaning until the difference between the light intensity of the irradiated light and the reference light intensity becomes less than the predetermined value, and if the difference between the light intensity of the irradiated light and the reference light intensity does not become less than the predetermined value even after performing the cleaning a predetermined number of times, the inspection of the object is stopped.

3. The light detection unit has a spectroscope (42) for measuring the spectral characteristics of the transmitted light, 2. The object inspection device according to claim 1, wherein the light detection unit reduces the gain of the spectroscope when detecting the irradiated light compared to when detecting the transmitted light.

4. 4. The object inspection device according to claim 1, wherein the cleaning unit is configured by an air injection unit (23, 24) that blows air onto at least one of the light-emitting end and the light-incident end.

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