JP3048049B1 - Foreign matter inspection system - Google Patents

Abstract

Kind Code: A1 Abstract: In a production line for producing liquid products such as beverages and liquid medicines, foreign substances contained in a liquid fluid flowing at high speed in a conduit can be detected, and the mixed foreign substances can be automatically eliminated. To do. An illuminating means (20) for illuminating the inspection object by irradiating light to an inspection window (10) made of a translucent member with a liquid fluid flowing through a cylindrical tube (1) as an inspection object, and An imaging unit 30 for receiving the transmitted light or reflected light of light with respect to the target and imaging the inspection target; a signal level obtained by inputting and enhancing a video signal captured by the imaging unit; and a reference level of the inspection target. Detecting means 40 for detecting foreign matter mixed in the fluid by comparing
Are provided. When the foreign matter is detected by the detection means 40, the flow path is temporarily changed to the branch pipe 60A side by opening and closing control of the control valve 60, and the fluid containing the foreign matter is automatically discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foreign matter inspection system for inspecting foreign matter mixed in a liquid product such as a drink or medicine, and more particularly, to a real-time system for detecting the presence or absence of foreign matter mixed in a liquid fluid flowing through a cylindrical pipe. The present invention relates to a foreign substance inspection system for performing inspection.

[0002]

2. Description of the Related Art In recent years, with the application of the HACCP method to the Food Sanitation Law and the enforcement of the PL (Product Liability: Product Liability) method, the manufacture / processing of products such as food and medicine, and the preservation / distribution of products have been promoted. It is becoming obligatory to prevent the occurrence of harm caused by microbial contamination or other contaminants that may occur at any stage until the final consumer ingests the product, and to further enhance the security of the product.

[0003] The HACCP method is called Hazard An.
alysis Critical Control Po
An abbreviation of int System, which is an internationally highly valued US hazard analysis and
It is an important control point method. The HACCP system is a scientific hygiene management system designed to ensure the safety of products throughout the entire manufacturing process. Focuses on process precautions. The HACCP system consists of two parts, Hazard Analysis (HA) and Critical Control Point (CCP), which occur at every stage from food production / processing, product storage / distribution to final consumption by the end consumer. Investigate / analyze harms such as microbial contamination that may cause harm, set important control points for harm prevention, set management standards, and check management records to confirm that measures are being taken appropriately within the limits. Always monitor, and for any other harm,
General hygiene management standards (PP: Pre-requisite)
By managing the program, it is possible to prevent the occurrence of harm in the manufacturing process without overlooking it and to further enhance the safety of the product.

[0004] Conventionally, in a manufacturing / processing plant for producing liquid products (drinks, liquid drugs, etc.), microbial contamination is prevented by subjecting a production line to sterilization treatment such as heat treatment, or a cyclone separator. To prevent foreign matter from being mixed in. And
After filling in containers such as cans and bottles, inspections of foreign matter in the bottles and the like are carried out as final product inspections. For example, soft drinks,
In a manufacturing / processing plant that produces a large amount of liquid products such as fruit drinks and vegetable juices, the liquid raw material that has been subjected to the above-described foreign substance removal processing is usually placed in a tank, and a cylindrical guide tube (hereinafter, referred to as a “tube”) The product is sent to a filling machine at high speed through a "pipeline", and automatically filled into containers such as cans and bottles being conveyed, so that products are mass-produced.

[0005]

However, in the above-mentioned manufacturing / processing plants, the foreign substances that may be mixed before the final product is manufactured are roughly classified into the mixing sources according to the sources. There are "material foreign material", "environmental foreign material" that is mixed from outside in a state where the material is not sealed, and "manufacturing machine foreign material" generated from the manufacturing machine itself in the production line. When removing foreign substances mixed into the liquid product, of these foreign substances, those having a specific gravity greatly different from that of the liquid product can be removed by a cyclone separator or the like. In addition, foreign substances larger than the particles of the raw material can be removed by a filter. When a liquid product is produced in a manufacturing / processing plant, such a foreign substance removing process is conventionally performed before processing, and an inspection of a final product is performed to ensure product safety.

[0006] However, even if the inspection or the foreign substance removal processing is performed on the raw material, there is a possibility that foreign substances may be mixed in the manufacturing / processing stage. For example, in a production line, there is a possibility that environmental foreign substances or foreign substances in a manufacturing machine may be mixed between a time when a liquid material is put into a tank and a time when the liquid material is transferred through a pipeline and filled in a container such as a can. As a countermeasure, for example, liquid products such as tea and milk can relatively easily remove foreign substances by providing a fine filter in the pipeline, but products containing fibrous materials can be used as filters. There is a problem that it cannot be removed by a method using a filter because it is clogged. Also,
When manufacturing products that mix materials of different sizes, such as granular materials, foreign substances larger than the granular substances can be removed with a filter at the raw material stage. There is a problem that it cannot be removed. In addition, there is a problem that the visual inspection cannot inspect or remove the fluid flowing in the pipeline.

[0007] Therefore, at present, when a product containing a fibrous material or a granular material is manufactured, a visual inspection person visually inspects a solution or additive in a tank containing the raw material, and if there is a foreign substance, a manual inspection is performed. Until the product was filled into the container through the pipeline after the removal was performed by the operation, no inspection for foreign matter and no foreign matter removal processing were performed.

SUMMARY OF THE INVENTION The present invention has been made under the above circumstances, and an object of the present invention is to provide a liquid production system for producing liquid products such as beverages and liquid medicines, which is used for producing a liquid fluid flowing at a high speed in a conduit. It is an object of the present invention to provide a foreign matter inspection system capable of detecting foreign matter contained therein and automatically removing the foreign matter mixed therein.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a foreign matter inspection system for inspecting foreign matter mixed in a liquid fluid flowing through a cylindrical tube with the object to be inspected. An inspection unit connected to the cylindrical tube, at least a portion of the inspection window for the foreign substance made of a light-transmitting member, and an illumination unit that illuminates the inspection window with light to illuminate the inspection target, An imaging unit that receives transmitted light or reflected light of the light with respect to the inspection target and captures an image of the inspection target; and a part where a video signal captured by the imaging unit is input and the level of the video signal changes rapidly. Detecting means for detecting a foreign substance mixed into the fluid by comparing the signal level obtained by performing the emphasis processing with the reference level of the inspection target , wherein the reference level is higher than the previous level.
The waveform of the analog video signal obtained by scanning with the
Shift by a predetermined threshold to the level side and low level side respectively
Indicated by the analog slice level band set as
A detection level, and
Analog video signal continuously while scanning a analog image
The signal level after the inspection is
By determining whether they are within the rice level band.
This is achieved by detecting the foreign matter in real time .

Further, the inspection window has a cylindrical shape or
It is formed in a flat shape and has a predetermined inclination at a cross-sectional portion on the circumference of the inspection window so that light from a light source is reflected at the cross-section and travels straight through the wall of the inspection window. An annular mirror surface having an angle is formed, and the illumination window irradiates light from the light source to the annular mirror surface portion so that the inspection window itself becomes a luminous body; This is achieved more effectively.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention detects foreign matter in a liquid flowing at a high speed in a guide tube and detects the foreign matter detected in a production line for producing liquid products, such as beverages and liquid medicines, especially taken by humans. It is automatically removed without stopping the production line. That is, according to the present invention, not only the raw material and the final product are inspected as in the related art, but also foreign substances generated in the product manufacturing / processing process, for example, “raw material foreign substances” that have not been completely removed by the raw material inspection, Detects "environmental foreign substances" that may enter during the loading stage and "manufacturing apparatus foreign substances" generated from the manufacturing machine itself during production, and automatically discharges the solution containing the foreign substances via a branch pipe or the like. Thus, the occurrence of harm due to the contaminating foreign matter is prevented beforehand, and the security of the product is further improved.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The foreign substance inspection system of the present invention is applicable not only to liquid products (products such as drinks and liquid medicines) which humans ingest, but also to general fluid foreign substance inspection systems. Hereinafter, a case where the present invention is applied to a manufacturing / processing factory for liquid foods and chemicals will be described as a specific example.

FIG. 1 shows an example of a basic configuration of a foreign substance inspection system according to the present invention. In FIG. 1, a window (hereinafter, referred to as an "inspection window") 10 for inspecting foreign matter mixed in a fluid is provided in a portion of the pipeline 1 through which a fluid material flows. ing. A branch pipe (discharge pipe for removing foreign substances) 60A is connected downstream of the control pipe via a control valve (reject valve) 60 for removing foreign substances. The inspection window 10 is a cylindrical tube having the same inner diameter as the inner diameter of the pipeline 1 (for example, an inner diameter of 40 mm), and the entire wall of the tube is formed of a light-transmitting member such as glass or a transparent polymer material. . In FIG. 1, the portion of the light-transmitting cylindrical tube 11 is shown in an enlarged manner.
One inspection window 10 is arranged side by side. One or a plurality of imaging devices (CCD cameras in this example) 30 are provided around the circumference of the light-transmitting cylindrical tube portion 11 of the inspection window 10, and an illumination device 20 (a strobe in the example of FIG. 1). 1,2)
The transmitted light or the reflected light of the light from the light source is received, and the fluid 2 passing through the portion of the inspection window 10 is imaged.

The object of inspection is a relatively transparent liquid fluid. In the case of a fluid having a degree of transparency such that light from the illumination device 20 passes through the translucent cylindrical tube 11, a single imaging device is used. 30, foreign matter 3 mixed in the fluid 2
Can be detected. In addition, light is transmitted through the cylindrical tube 11.
When a semi-transparent fluid that reaches the center of the cylindrical tube but does not pass through the tube is to be inspected, the imaging device 30 is moved around the translucent cylindrical tube 11 so that the entire peripheral wall of the cylindrical tube can be imaged. In this configuration, foreign substances in the fluid can be detected by arranging them at equal intervals in the direction of and inspecting from a plurality of directions. In the example of FIG. 1, the imaging device 30 has an imaging area in the radial direction of the cylindrical tube larger than the diameter of the tube, and the two imaging devices 30 (camera 1 and camera 2) are connected to the cylindrical tube portion 11.
Are arranged side by side in the longitudinal direction and are opposed to each other (they are opposed to each other on the same circumference without juxtaposition), so that the cylindrical pipe portion 11
Is configured to be able to image the entire region of the translucent fluid that passes through. Further, when a fluid that does not reach the center of the translucent cylindrical tube 11 or an opaque fluid is targeted, similarly, a light receiving sensor unit 30 such as a camera is provided to receive reflected light from a plurality of directions. With this configuration, it is possible to inspect at least the entire surface of the fluid.

The image processing device 40 receives a video signal picked up by the image pickup device 30 and detects a foreign substance in the liquid by comparing the signal level with a preset reference level of the inspection object. In other words, fluid materials to be inspected, such as beverages and liquid medicines, have almost constant transmittance and reflectance for light of a specific wavelength in a state where no foreign matter is mixed, so that the level of a captured video signal is also low. It is almost constant. Therefore, if the average value or the range is set as the reference level, foreign matter can be detected based on the amount of change in the video signal. For example, in the case of juice containing fibers and granules of fruits and vegetables, the level of the video signal of each component (or the level of the video signal when the fluid after mixing is targeted)
Is set in advance as a reference level, and when a sudden change in the video signal with respect to the reference level is detected, it is determined that a foreign substance is included. At this time, since image processing cannot be performed in time if digitized and processed based on image data stored in a line memory, a frame memory, or the like, the image processing device 40 uses an analog device obtained by scanning with the imaging device 30. The video signal is compared with the reference level, and an analog image is continuously inspected.
For example, when producing 8 to 10 tons of beverage per hour through a pipeline, the flow rate in the pipe depends on the diameter of the pipeline and the speed at which the solution is sent out, but the flow rate is 1 m / sec.
It is about 2 m. Therefore, when inspecting such a high-speed fluid, in an image processing method of sequentially processing sampled and quantized digital images in frame units, there is a possibility that a part of inspection is omitted due to thinning.

Therefore, according to the present invention, an analog video signal obtained by scanning with the imaging device 30 is input as described above, and the level of the analog video signal is reduced so that foreign substances contained in a high-speed fluid can be detected without leakage. The signal level obtained by enhancing the rapidly changing part and the waveform of the video signal before the enhancement processing are shifted to the high level side and the low level side by predetermined thresholds S1 and S2, respectively.
Inspection is performed by comparing with the analog slice level band set by shifting by minutes. That is, while scanning a temporally continuous analog image, the video signal before sampling and quantization is continuously inspected, and the signal level after the enhancement processing is within the analog slice level band set in real time. The detection of foreign matter in liquid flowing at a high speed in the guide tube is detected in real time depending on whether or not the liquid is in the pipe. The emphasis processing and the analog slice level band setting processing will be described later with reference to waveform examples.

The control unit of the image processing device 40 is connected to the illumination device 20 and a control panel 50 of a reject valve (control valve for removing foreign substances) via an input / output interface device. Sometimes the control valve 60
By temporarily changing the flow path to the branch pipe 60A side by the opening / closing control, the fluid material containing foreign matter is discharged through the branch pipe 60A. The velocity of the fluid 2 passing through the inspection window 10 is constant, and in this example,
The time for the detected foreign matter to reach the reject valve 60 and the time for opening and closing the valve (change time of the flow path) are based on information on the distance between the detection window 10 and the reject valve 60 and the flow rate of the inspection target. Is set in advance for each inspection object. However, the foreign matter may fluctuate in flow velocity depending on its specific gravity or shape, or may temporarily stay due to a swirling motion. A value that takes minutes into account is set. It should be noted that a flow rate sensor may be provided, and the opening / closing time may be controlled based on flow rate detection information, without setting the time related to the opening / closing control in advance.

The control unit of the image processing apparatus 40 controls the illumination of the illuminating device and the interlocking control with the filling device for filling the product container with the fluid, in addition to the above-described discharge control of the foreign matter. In this example, the stop of the filling device is detected by inputting the control signal of the filling device, and the detection output (output of the inspection result) is stopped in conjunction with the stop of the filling device.
Note that a flow sensor may be provided near the inspection window 10 and the stop of the filling device may be detected by detecting the presence or absence of a fluid using the flow sensor.

Next, the configuration of the lighting device according to the present invention will be described. In the pipeline 1 for transferring a fluid, at least a portion of the inspection window 10 is formed of a light-transmitting cylindrical tube as described above. When illuminating a fluid flowing through such a translucent cylindrical tube, when illuminating from one direction on the circumference,
It is necessary to accurately arrange the light receiving elements in consideration of the refraction of the liquid and the reflection / refraction at the wall of the cylindrical tube, and the installation place is limited. Further, depending on the state of light reflection, a foreign substance is hard to be imaged, and there is a possibility that inspection may be omitted. Therefore, in the present invention, the wall itself of the translucent cylindrical tube serving as the inspection window serves as the light emitting body.

FIG. 2 schematically shows an example of the configuration of the illumination device. The light-transmitting cylindrical tube portion 1 of the inspection window 10 shown in FIG.
1 is a cross-sectional view illustrating an example of a configuration of a light emitting unit of the lighting device 20. In FIG. 2, the light from the light source is reflected at the cross-sectional portion on the circumference of the light-transmitting cylindrical tube portion 11 so that the light travels straight through the wall of the light-transmitting cylindrical tube portion 11. An annular (frustoconical shape) mirror surface 12 having a predetermined inclination angle is formed. Then, by irradiating uniform light from the circumferential direction (the emission surface 21a of the light emitting unit 21 in FIG. 2) to the entire area of the annular mirror 12, the annular light is transmitted to the inside of the wall of the translucent cylindrical tube 11. Since the light travels straight through the entire area, the translucent cylindrical tube 11 itself becomes a light emitting body. With such a configuration, the light applied to the fluid 2 becomes uniform, it is possible to detect any foreign matter at any position in the tube, and the degree of freedom of the installation location of the imaging device is increased. , Easy installation. In this example, an optical fiber is used as the light emitting means, and the distal end portion 21 of the optical fiber is arranged on the circumference as shown in FIG. 2, so that the light emitting surface 21a irradiates the mirror surface portion 12 with uniform light. The wavelength and intensity of the light emitted from the light source of the optical fiber are set in advance according to the characteristics of the inspection target, and the light is emitted at a specific wavelength and intensity based on the set values of the inspection target. At this time, light of a plurality of wavelengths may be emitted according to the inspection target so that the difference in the transmittance and the reflectance of the inspection target light is remarkable.

Next, a description will be given of an arrangement of a foreign substance inspection apparatus in a production line for preparing a plurality of materials. First, a general beverage product production line will be described with reference to FIG. FIG. 3 schematically shows a production line in a factory that produces a beverage product in which a syrup 2a and a cell 2b of a plant (fruit or vegetable) are mixed.

In a factory that produces a beverage product in which a plurality of ingredients are mixed, each ingredient is put into each tank 4 alone.
The raw materials in each tank 4 are fed through a conduit to a mixing device (holding) 6 to be mixed, and the prepared beverage is filled through a pipeline 1 into a filling device (filler) 7.
To produce beverage products by filling containers such as cans and bottles.

In the example shown in FIG. 3, the inspection of foreign substances is carried out in the compounding process before the respective fluid materials join in one pipeline 1 through the conduit and before they are sent to the mixing device 6 through the pipeline 1. And the detection foreign matter is eliminated. In this case, the inspection window 10 of the foreign matter inspection device is provided at an arbitrary position in the pipeline 1 after the merging, and a reject valve 60 for removing foreign matter is installed downstream thereof. In this example, a thermocylinder 5 for measuring the temperature during the blending process is provided upstream of the inspection window 10, and the control unit of the foreign matter inspection system (or the management computer) controls the temperature in the blending process. In addition to recording the history, the foreign substance detection status and the exclusion status are recorded.

FIG. 4 shows another example of the arrangement of the foreign matter inspection apparatus. This example is provided between the mixing device 6 and the filling device 7, specifically, downstream of the mixing device 6. In the mixing process between the head tank 8a, the liquid feed pump 8b, and the filling device 7, the inspection of foreign substances is performed and the detected foreign substances are eliminated. In this example, the mixing device 6
In this case, the fluid after mixing is to be inspected, but the inspection method for foreign substances is the same as the case of the arrangement of FIG. 3, that is, the case where the fluid before being mixed by the mixing device 6 is to be inspected. still,
In this example, as shown in FIG.
A detour path is provided in the pipeline via 3 and a reject valve 61 is provided in the detour path. That is, while the fluid containing foreign matter is discharged, the flow path is switched to the bypass path side by the distribution valves 62 and 63, and the reject valve 61 is opened. By controlling the reject valve 61 to be closed, the foreign matter can be removed smoothly.

Next, an example of the operation of the system of the present invention in the above configuration will be described with reference to FIG. 1 and along the flowchart of FIG.

The imaging device 30 images the fluid 2 passing through the translucent cylindrical tube 11 (step S1). When the video signal is input from the imaging device 30 (step S2), the image processing device 40 enhances the portion where the signal level changes abruptly, and performs the analog processing based on the video signal before the enhancement process. A slice level band is set, and it is checked whether or not the level of the analog video signal after the enhancement processing is within the analog slice level band. Here, the video signal from the imaging device 30 is an analog video signal that is temporally continuous. For a line sensor, an output signal of each light receiving element, and for a two-dimensional area sensor, for example, a horizontal scanning signal is input. Then, it is continuously checked whether or not the analog video signal after the emphasis processing is within the analog slice level band (step S3).

FIGS. 6A, 6B and 6C show examples of waveforms of the analog video signal Vi obtained by scanning with the imaging device 30.
7A and 7B show a waveform example of the analog video signal Vi ′ after the emphasis processing and a relationship between the analog video signal Vi ′ after the emphasis processing and the analog slice levels VS1 and VS2, respectively.
An operation example at the time of inspection will be described with reference to FIG. When foreign matter is contained in the fluid, the level suddenly increases as the luminance changes, as shown by V1, V2, and V3 in FIG. 6A (in this example, there are three foreign matters). Change.

In the image processing device 40, the video signal Vi is differentiated and compared with a predetermined threshold value, and a portion where the amount of change of the differential value is large, that is, a portion where the signal level rapidly changes as shown in FIG. The signals of V1, V2, and V3 (in this example, the portion where the luminance change is large) are amplified and emphasized. This emphasizing process is performed in real time, and the signal Vi ′ subjected to the emphasizing process is used for foreign substance inspection as shown in FIG. At this time, in the present invention, the original signal waveform (the waveform of the video signal before the enhancement processing shown in FIG. 6A) as shown in FIG.
On the high level side and the low level side respectively.
S2 (S1 = S2 in this example) is shifted by the first and second
Of each analog slice level VS1 and VS2 of
These slice levels (differential slice levels) VS
An analog slice level band consisting of 1 and VS2 is used as a reference level for foreign substance inspection.

The detection unit of the image processing device 40 determines whether or not the analog signal level after the emphasis processing is within the analog slice level band (step S4). It is determined that they are mixed, and a detection result (for example, “0” is normal and “1” is foreign matter detection) is output via the A / D converter. FIG.
In the example of (1), it is determined that foreign matters are mixed in the portions P1, P2, and P3 in FIG. Note that FIG.
In the example, the threshold value S for the undiluted solution “syrup” 2a
1 (a) and S2 (a) and a threshold value S1 for a fibrous or granular “cell” 2b which is a material to be mixed with the stock solution.
(B) and S2 (b) are set in advance, respectively.
If the analog signal level after the emphasis processing is not included in any of the analog slice level bands respectively set based on the thresholds, it is determined that foreign matter has been mixed, and a detection result indicating foreign matter detection is output. (Step S5).

The control section inputs a detection output, and if a foreign substance is detected, switches the flow path to the branch tube 60A through the control panel 50, and controls the control valve for a predetermined period corresponding to the inspection object. 60 is opened to remove foreign matter (step S6). The operations in steps S1 to S6 are repeated during the period when the filling device is operating (the period when the production line is operating). If the filling device is stopped (step S7), the operation related to the foreign substance inspection is performed. It ends, and it becomes a standby state.

In the above-described embodiment, the example of the configuration of the inspection window is an example in which only the inspection window portion of the pipeline for transferring the fluid is made of a translucent member. It is sufficient that the portion is formed of a light-transmitting member, and the entire tube may be made of a light-transmitting member. In addition, as an example, a cylindrical tube having the same inner diameter as the pipeline is used as the translucent cylindrical tube serving as the inspection unit. A pipe having an inner diameter larger than the inner diameter of the pipeline may be used.

However, in the case where the inner diameter of the inspection portion is made larger than the inner diameter of the pipeline, the imaging range can be widened, so that it can be suitably applied to a system having a small pipeline diameter. On the other hand, there is an advantage that the flow rate changes due to the difference in inner diameter,
There is a drawback that turbulence such as eddy currents may occur and foreign matter to be inspected may stay. Therefore, it is more effective to make the cross-sectional area of each part of the inspection unit through which the fluid flows the same as the cross-sectional area of the pipeline and make the inspection window part a flat shape.

FIG. 7 shows an example of the configuration of the inspection section when the inspection window has a flat shape, and is a plan view of FIG. 7A and a partial sectional side view of FIG. A description will be given of another preferred configuration of the inspection unit with reference to FIG.

7 (A) and 7 (B), the inspection section connected to the pipeline 1 has an inspection window 10 made of a translucent member at least in a flat shape (in this example, a rectangular thin plate). The cross-sectional area of the connecting portion (the inflow portion 10a and the outflow portion 10b in FIG. 7A) with the pipeline 1 and the cross-sectional area of the inspection window 10 (the cross-sectional area of the portion through which the fluid flows) Are all formed to be the same as the cross-sectional area of the pipeline 1. That is, the cross-sectional area of the inflow portion 10a, the flat inspection window 10, and the outflow portion 10b is the same as the cross-sectional area of the pipeline 1 irrespective of the section. The joint 10c uses a general valve.

In such a configuration, when the pipeline 1 and the inspection unit are cut at equal intervals, the integral value of each unit becomes constant, and the unit time tn shown in FIG.
And flow velocity Vn, t1 = t2 =... = T6, V1 = V2 =
.. = V6. In other words, the flow rate is always constant, and it is possible to avoid stagnation of foreign matter due to a change in the flow velocity. Further, since the inspection window is formed in a thin plate shape, it has excellent light transmittance. As shown in FIG. 7B, a general light projecting means 20 is provided at a position facing the camera 30. As a result, the cost can be reduced at a lower cost as compared with the above-described configuration in which the entire inspection window emits light. Further, since a planar imaging area can be secured in a wide area, it is possible to further improve the inspection accuracy of foreign substances.

Next, a method for avoiding the influence of turbulence that may occur upstream and downstream of the inspection unit will be described.
The turbulence that affects the inspection includes turbulence in the liquid flow such as a change in pressure and a change in concentration of the flowing liquid, in addition to the vortex flow described above. If the turbulence of the liquid flow occurs upstream of the inspection unit, the inspection accuracy may be reduced. Further, for example, in a configuration in which a control valve for removing foreign matter is provided downstream of the inspection unit, a turbulence in water pressure occurs due to opening and closing of the control valve,
The turbulence may affect the inspection unit side, and the turbulence of the flowing liquid generated in the inspection process may affect the downstream side. To avoid the effects of such turbulence,
It is effective to provide a turbulence buffer tank (balance tank).

FIG. 8 is a block diagram showing a first example of a foreign substance inspection system provided with a turbulence buffer tank, corresponding to FIG. 3, and the same components are denoted by the same reference numerals and description thereof is omitted. I do. 8, turbulence buffer tanks 70a and 70b are provided upstream and downstream of the inspection unit (inspection window) 10, respectively. The turbulence buffer 70 a provided upstream of the inspection unit 10 flows in the fluid flowing at high speed in the pipeline 1, reduces turbulence of the flowing liquid, and flows out to the inspection unit 10 side. On the other hand, a turbulence buffer tank 70b provided downstream of the inspection unit 10 via a control valve 60 for removing foreign matter.
Flows out of the fluid from the inspection unit 10 to alleviate the turbulence of the flowing liquid and flow out. With such a configuration, it is possible to avoid a decrease in inspection accuracy due to turbulence of the flowing liquid, and
The turbulence of the flowing liquid generated in the inspection process can be prevented from affecting the downstream process. Further, in the case of the configuration example shown in FIG. 4, as shown in FIG. 9 corresponding to FIG. 4, the turbulence buffer tanks 70a and 70b may be arranged upstream of the inspection unit 10 and downstream of the distribution valve 63, respectively. good.

In the embodiment in which a plurality of inspection units 10 are arranged side by side, as shown in FIG. 10 corresponding to FIG. 8, the flow buffer tanks 70a and 70b are each connected to each inspection unit 1 similarly to FIG.
0 may be arranged upstream and downstream. In the example of the foreign matter inspection system shown in FIG. 10, the turbulence buffer tank 70a provided upstream of each of the juxtaposed inspection units 10 includes:
The fluid flowing in the pipeline 1 at a high speed flows in to alleviate the turbulence of the flowing liquid, and diverges to flow out to each inspection unit 10 side. On the other hand, a turbulence buffer tank 70b provided downstream of the inspection unit 10 via a control valve 60 for removing foreign matter is provided with:
The fluid from each inspection unit 10 flows in and merges, and at the same time, flows out while reducing turbulence of the flowing liquid. In the case of such a configuration, the turbulence buffer tank 70a can equalize the supply of the liquid to the pipe that is divided into a plurality of pipes from the tank, and stabilize the water pressure applied to each inspection window.

In the configuration shown in FIG. 10, for example, in a production line for producing a liquid product at a speed of 20 t / h, the flowing liquid flowing at a flow rate of 20 t / h from the upstream is divided by a turbulence buffer tank 70a. , Each with a flow rate of 10 t / h
It flows into three inspection units 10 and is inspected. Then, the flowing liquid after the inspection (the flowing liquid after removing the foreign matter) is supplied to the turbulence buffer tank 70.
b and are discharged at a flow rate of 20 t / h. In addition, a liquid feed pump is provided at each of the outlets of the turbulence buffer tanks 70a and 70b, and the turbulence buffer tanks 70a and 70b are provided.
The capacity of b may be equal to or greater than the total capacity of the charging tanks containing the raw materials, and may be stored / stored in the turbulence buffer tanks 70a and 70b before starting / restarting the liquid feeding. good.

[0040]

As described above, according to the present invention, in a production line for producing liquid products such as beverages and liquid medicines, foreign substances are detected by inspecting a fluid material transferred in a conduit. In addition to this, it is possible to automatically remove foreign matter mixed in each material even if the product contains a fibrous or granular material. For this reason, it is possible to eliminate foreign substances that may be mixed in a container such as a can or a bottle or the like immediately before filling the container into a final product, thereby further improving the safety of the product.

Further, a signal obtained by scanning a portion where the level of an analog video signal obtained by scanning with an image pickup device rapidly changes is subjected to a comparison with a reference level, and a continuous inspection is performed while scanning an analog image. In this way, high-speed fluid that flows at a speed that would not be enough to process digitized pixel data can be inspected, and fine foreign substances contained in the fluid can be inspected in real time. Can be detected. Further, the waveform of the analog video signal is shifted to the high level side and the low level side by a predetermined threshold, respectively, and the analog slice level band is set as a reference level, and the signal level after the emphasis processing falls within the analog slice level band. Inspection accuracy is further improved by detecting foreign matter depending on whether or not there is.

Further, since the light-transmitting cylindrical tube itself, which is the inspection section, is used as a light-emitting body so that the fluid flowing through the light-transmitting cylindrical tube can be uniformly irradiated with light, foreign matter in the tube can be prevented. Detection can be performed at any position, and the degree of freedom of the installation location of the imaging device is increased, which facilitates installation. Further, in the system configuration using the inspection unit in which the inspection window is formed in a flat shape and the entire inspection unit has the same cross-sectional area as the conduit, the cost can be reduced and the inspection accuracy can be increased. Becomes possible. Furthermore, in a system configuration in which a turbulence buffer tank is provided upstream and downstream of the inspection unit, the pressure and concentration changes of the flowing liquid that can occur upstream of the inspection unit are caused by the opening and closing of the control valve in the inspection process. It is possible to avoid a decrease in inspection accuracy due to turbulence in the flowing liquid, such as a possible pressure change, and to prevent the turbulence in the flowing liquid from affecting downstream.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a basic configuration of a foreign substance inspection system according to the present invention.

FIG. 2 is a cross-sectional view schematically illustrating an example of a configuration of a lighting device used in the present invention.

FIG. 3 is a block diagram showing an example of an arrangement configuration of the foreign matter inspection device of the present invention.

FIG. 4 is a block diagram showing another example of the arrangement of the foreign matter inspection device of the present invention.

FIG. 5 is a flowchart showing an operation example of the system of the present invention.

FIG. 6 is a diagram for explaining an image processing method according to the present invention.

FIG. 7 is a plan view and a partial cross-sectional side view illustrating another configuration example of the inspection unit according to the present invention.

FIG. 8 is a block diagram showing a first example of a foreign substance inspection system provided with a turbulence buffer tank according to the present invention.

FIG. 9 is a block diagram showing a second example of the foreign substance inspection system provided with the turbulence buffer tank according to the present invention.

FIG. 10 is a block diagram showing a third example of a foreign substance inspection system provided with a turbulence buffer tank according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipeline 2 Liquid fluid 3 Foreign material 4 Tank 5 Thermocylinder 6 Mixing device 7 Filling device 10 Inspection window 11 Translucent cylindrical tube 12 Mirror surface 20 Illumination device 21 Light emitting part 30 Imaging device 40 Image processing device 50 Control panel 60 Control valve 60A Branch pipe 70a, 70b Turbulence buffer tank

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-9-257717 (JP, A) JP-A 1-214738 (JP, A) JP-A 1-107158 (JP, A) JP-A-6-257 43104 (JP, A) JP-A-8-278247 (JP, A) JP-A 64-15151 (JP, U) JP-A-5-3988 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01N 21/84-21/958 G01V 9/04

Claims (2)

(57) [Claims] 1. A foreign matter inspection system for inspecting foreign matter mixed into a fluid by using a liquid fluid flowing through a cylindrical pipe as an inspection object, wherein the foreign matter inspection system is connected to the cylindrical pipe and has at least a window for inspection of the foreign matter. An inspection part whose portion is formed of a light-transmissive member, illumination means for irradiating the inspection window with light to illuminate the inspection object, and receiving transmitted light or reflected light of the light with respect to the inspection object; An imaging unit that captures an image of the inspection target, a video signal captured by the imaging unit, and a signal level obtained by enhancing a portion where the level of the video signal changes rapidly, and a reference level of the inspection target. Detecting means for detecting a foreign substance mixed into the fluid by comparing , wherein the reference level
High-level analog video signal waveforms obtained by scanning
Side and low level side, respectively,
The reference level indicated by the specified analog slice level band
A bell, and the detecting means is an analog of the test object.
Continuous inspection of analog video signals while scanning images
The signal level after the emphasis processing is
By determining if it is within the level band
A foreign matter inspection system for detecting foreign matter in real time . 2. The inspection window is cylindrical or flat.
A predetermined inclination angle such that light from a light source is reflected by the cross-section and travels straight through the wall of the inspection window at a cross-section on the circumference of the inspection window. an annular mirror is formed which forms, claim adapted to the inspection window itself and the light emitting element by irradiating light from the light source to the mirror surface portion of the annular by the illumination means 1 The foreign matter inspection system according to 1.