JPS63263489A - Detection of object to be detected by fluorescence emitting body - Google Patents

Abstract

PURPOSE:To detect an object to be detected without being affected by diffused external light, etc., by providing at least >=2 photodetecting elements and subjecting the output values of the respective photodetecting elements to a subtraction process. CONSTITUTION:A detecting part 2 is so constituted that the outputs of photodiodes 41, 42 are inputted by codes to a substrate 55. A photodetecting part 40 is constituted of the photodiodes 41, 42 and an arithmetic circuit 50 of operational amplifiers 51-53 in such detecting part 2. Photodetection signals DS1, DS2 of the polarity values reverse from each other are inputted from the photodiodes 41, 42 of the photodetecting part 40 to the operational amplifier 53 of the arithmetic circuit part 50. The difference between the two signals DS1 and DS2, i.e., a fluorescence emission signal DS5 indicating the fluorescence of glue is inputted to the amplifier 54, from which a detection output KS1 is outputted. The signal levels of the computed signals from the influence of the diffused external light and improving the S/N without weakening the emission intensity of the detected fluorescence by subtracting the signal levels of the arithmetic signals DS3, DS4 from the two photodiodes 41, 42 are subtracted to form the signal DS5 in this photodetecting part 2, by which the influence of the diffused external light is eliminated and the S/N is improved without weakening the emission intensity of the detected fluorescence.

Description

Detailed Description of the Invention (Technical Field of the Invention) This invention is directed to detecting the presence or absence of a detection object having a fluorescent light emitting substance,
The present invention relates to a method of detecting an object using a fluorescent light emitter, which efficiently detects the position of the object without being affected by ambient light or changes in color or quality of the object.

(Technical background and problems to be solved) Conventionally, one of the methods for detecting the presence or absence of an object to be detected, the amount of the object, etc. was to attach a fluorescent material to the object to be detected, or add or coat a fluorescent agent. This was done by irradiating the object with ultraviolet light and detecting the generated fluorescence with a light-receiving element. However, the fluorescence intensity of fluorescent substances is inherently very weak, so in order to improve the recognition rate, it is necessary to surround the detection device, ultraviolet source, and workpiece with a light-shielding plate or a light-shielding box to eliminate the effects of ambient light. However, since it requires a special box, etc., it has the disadvantage that the range of applications is greatly limited. Therefore, as an improvement to the above method, a method has been considered in which an optical filter or the like is provided in front of the light receiving element to selectively detect only the fluorescence of the fluorescent substance. However, in this method, since the fluorescence of the fluorescent substance, which is originally very weak, is received through a filter, the output signal from the light receiving element becomes even weaker, and the subsequent amplifier circuit etc. becomes extremely weak. Xtiff and S
There is a drawback that the /N ratio also decreases. Moreover, expensive devices are required for signal processing, and the apparatus becomes complicated. As described above, there is currently no inexpensive and easy way to detect fluorescent substances, so the actual situation is that humans perform visual confirmation. However, this method has very poor production efficiency as it requires people to perform simple tasks for long periods of time and to look at weak light in dark places, and there are also problems in terms of health and safety. Ta.

(Object of the invention) This invention was made under the above circumstances,
The purpose of this invention is to detect an object provided with a fluorescent light emitter with a plurality of light receiving elements, thereby detecting the object with a good S/N ratio, and to automate the inspection process and improve production efficiency. An object of the present invention is to provide a method for detecting an object using a light emitting body.

(Means for Solving the Problems) The present invention provides a detection object using a fluorescent light emitting material, in which a detection object having a fluorescent light emitting material is irradiated with ultraviolet rays, and the fluorescence of the fluorescent light emitting material is detected by a light receiving element. Regarding the detection method, the above-mentioned object of the present invention is to provide at least two or more light receiving elements and perform subtraction processing on the output value of each light receiving element.
The object to be detected is affected by ambient light or changes in color of the object to be detected,
This is achieved by detecting without being affected by changes in quality, etc.

(Operation of the Invention) This invention irradiates ultraviolet rays onto a detection object having a fluorescent light emitter, receives the fluorescence from the fluorescent light emitter and ambient light with a plurality of light receiving elements such as photodiodes, and outputs data. By processing with a subtraction circuit, the object to be detected is detected with a good S/N ratio (even if there is ambient light).

(Embodiments of the Invention) FIG. 1 shows how a gluing defect detection device that realizes the method of detecting an object using a fluorescent light emitter of the present invention is used in a collating machine. The gluing defect detection device is composed of an ultraviolet source 1, a detection section 2, an analog signal amplifier 3, and a device main body 10, which are attached to a support member 25 of a collating machine.
Each part is connected by a signal cord 4.5 and a power cord 6, and the continuous sheets 21A and 21B are conveyed.

It is designed to detect gluing defects and the amount of glue. The main body of the device 10 has a power switch 16 on its front panel.
Reset switch 17. Lamp lit on ν18. A lamp 19 that lights up when the gluing situation is poor;
A display 100 is provided to display the amount of glue, and a warning buzzer 15 is provided on the side panel of the main body 10 of the apparatus to issue an alarm when the glue is in poor condition.

Figure 2 shows the collating machine and ultraviolet light source 1. The positional relationship with the detection unit 2 is shown, and the continuous paper 2 is located at the bottom of the collating machine.
Rolls 20^, 20B on which the sheets 1A, 21B are wound are provided, and the continuous paper 21A, 21B sent out from these rolls 20^, 2011 in the direction of the arrow is passed through bin wheels 24^, 24B provided above. It is designed to be conveyed in the direction of arrow E. A glue applicator 22 for applying glue to the continuous paper 21A being conveyed is provided near the pin wheel 24A, and above the pin wheel 24A, the continuous paper 21 being conveyed is provided.
A flywheel 23 is provided for pressing and joining the parts A and 2111. Here, the detection unit 2 is located above the glue applicator 22, and further above this, the detection unit 2 is located above the pin wheel 2.
At the stage when the glue 30 is applied to the continuous paper 218 sent in the direction of the arrow E through the paper 48, the ultraviolet source 1 irradiates the glue 30 with ultraviolet BL, and the detection unit 2 detects the fluorescence from the glue 30. And only L1 and 1 and 2 are efficiently detected as disturbance light.

FIG. 3 shows the circuit system of the adhesive detection device in block form, and the details thereof will be explained below.

1) Ultraviolet source 1; A fluorescent black light or the like is used as the ultraviolet source 1.
The glue 30 (to which a fluorescent agent has been added in advance) applied to the conveyed continuous paper 21^ is irradiated with ultraviolet BL. In addition to keeping the intensity of the irradiated ultraviolet rays constant over time, high frequency power (approximately 20 KIIZ) is used to turn on a fluorescent black light at high frequency in order to stabilize the fluorescence of the glue 30. By arranging the light-receiving surface of UV light source 2 and the ultraviolet light source 1 at 45 degrees, the incidence efficiency of the UV light BL emitted by UV source 1 directly entering the light-receiving surface of the detection section is reduced and the S/N ratio is improved. I'm letting you do it.

2) Detection unit 2; The detection unit 2 has a structure as shown in FIG. 4, and converts the fluorescence and disturbance light Ll received from the light receiving feeds 43 and 44 and the disturbance light 162 into electrical signals. The signal is processed and transmitted as a detection signal KSI to the device main body lO by a signal code 4. Inside the detection unit 2, photodiodes 41' and 42 having a measurement wavelength in visible light are used, and an ultraviolet source is used. The fluorescent light of the glue emitted by L, the ambient light L1, and the ambient light L1 are received for photoelectric conversion, and the output polarities of the photodiodes 41 and 42 are reversed. Furthermore, the photodiode used has a wide measurement field of view, and the measurement field of view can be easily set by changing the shape of the light receiving section or the lens system.

The output of photodiodes 41 and 42 is connected to the board 55 by code.
It is becoming more and more human-powered. On the board 55, an IC
Three operational amplifiers 51, 52° 53 and an amplifier 54 consisting of
and is provided. The detection section 2 has a circuit configuration as shown in FIG.
．． 42 constitutes a light receiving section 40, and operational amplifiers 51 to 53 constitute an arithmetic circuit section 50. From the photodiodes 41 and 42 of the light receiving section 40, light receiving signals 501 and 502 of mutually opposite polarity are sent to the operational amplifier 5 of the operational circuit section 50.
1.52, and the operational amplifier 51.52 or 6
+73 calculation signal DS3. DS4 h<g”Q calculation amplifier 5
3: The difference between the two light reception signals 051 and DS2, that is, the fluorescence emission signal 055 indicating the fluorescence of the glue is detected by the amplifier 5.
4, and a detection signal KSI is output. That is, in this detection section 2, two photodiodes 41.4
Operation signal 053 from 2.

By subtracting the signal level of DS4 to obtain a fluorescence emission signal DS5, without weakening the emission intensity of the received fluorescence,
The effect of ambient light is removed and the S/N ratio is improved.

3) Analog signal amplifier 3; The analog signal amplifier 3 is an MO5 type human-powered operational amplifier, etc.
The detection signal 51 is easily distinguished from the detection signal received by the detection unit 2 and photoelectrically converted, and the signal-to-noise ratio is improved, and the signal is output to the subsequent circuit.

4) Apparatus body 10゜a) Judgment section ■A/[1 conversion section 11 ^/D conversion section 11 is composed of a timing pulse control circuit, a clock generation circuit, a sample hold circuit, an ADD conversion circuit, etc., and converts analog signals. The detection signal S2 from the amplifier 3 is sampled and converted into a digital signal, which is manually input to the one-board computer 12 for control. The timing pulse control circuit converts clock pulses of a constant period generated from a clock generation circuit that controls the operation timing of the sample and hold circuit and the conversion circuit into the converter according to the control pulses sent from the one-board computer 12 for control into /D. The time required for 10 to 10 conversion is determined by manually inputting a clock to the conversion circuit.

The sample and hold circuit samples the analog voltage during D/D conversion and fixes it at the data value at that time in order to eliminate conversion errors during D/D conversion. Sampling is performed at a rate of about llz. The A/D conversion circuit uses a commercially available 8-bit successive conversion type 810 conversion IC, the input terminal is bipolar, the input signal range is widened to simplify the entire circuit, and the output side has each bit A buffer is built in to take measures against noise.

■Control computer 12; The control computer 12 is a one-board computer, and includes a central processing unit (CPU), storage device (RAM,
iPROM), human output interface (1'PI)
, a decoder, a timer, etc., and the signal strength is input from the previous stage circuit via the human output interface, and the signal strength is the signal strength when the glue is completely attached, and the Shingetsu strength when there is no glue at all. The signal strength that indicates a defective product is determined from the two values, and the determined value is stored in a storage device as a determination value. After that, the central processing unit compares the Daichi No. 8 value sequentially read from the human output interface with the judgment value stored in the storage device to determine the presence or extent of gluing defects, and determines whether gluing defects are present or not. Then, the central processing unit calculates a judgment signal 85 and inputs it to the alarm device 13 via the input/output interface. Also, set the value corresponding to the amount of glue in advance (digital value).
is stored in a storage device, and the input signal read in as described above is judged and displayed on the display 100.

■Alarm device 13: The alarm device 13 is composed of a relay sequence, etc., and the alarm buzzer 1 is activated by the judgment signal Its from the control computer 12.
The control signal PS2 for outputting the control signal PSI for operating the lamp 19, etc.
Enter.

b) Operation unit 14: The operation unit 14 includes a power switch 16. Reset switch 17. Consisting of lamps 18 and 19, the operator activates the gluing defect detection device, checks the gluing situation, and resets the device main unit lO when gluing defect occurs to return to a detectable state again. It is designed to let you do so. When using the detection device, the operator presses the power switch 16, and after a gluing failure occurs and measures have been taken, the operator presses the reset switch 17. In such a configuration, the operation of the defective gluing detection device used in the T-jointing machine will be described.

First, a gluing defect detection device is set in the T-jointing machine as shown in FIG. 1, and the glue 30 to which a fluorescent agent has been added is placed in the glue applicator 22 in advance. Then, when the T-combining machine is operating, the operator turns on the power switch 16 installed on the main body 10 of the device to operate the glue (1) defect detection device. 1^, glue 30 is applied by the glue applicator 22, and the fluorescence of the glue 30 excited by the ultraviolet light source 1 and the disturbance light XL1 and the disturbance light XL2 are detected by the detection unit 2, and are transmitted through the analog signal amplifier 3. , device body
It is input to ^/D converter 11. Control computer 12. Processed by the alarm device 13, the lamp 1 of the operation unit 14
8 is lit to indicate that the gluing condition is good. Here, if a defect occurs in the gluing of the continuous paper 21^, it is detected by the detection section 2, and a sound is emitted from the alarm buzzer 15 provided in the main body IO of the apparatus, and the lamp 19 of the operation section 14 lights up. warning to the operator. The operator must stop the T-combining machine and process continuous paper 2.
After checking for gluing defects in 1^ and 21B, press the reset switch 17 on the operating section to reset the main body 10 of the device and operate the T-jointing machine again. Furthermore, since this gluing defect detection device displays the amount of glue on the display 100, the operator can also control the quality of gluing by checking the amount of glue.

The amount of fluorescent agent contained in the glue is 1% to 5%.
% aqueous solution at a ratio of 0.3% to 10%, and in the example, a 4% aqueous solution was contained at a ratio of 1%. In addition, in the above embodiment, a one-board computer was used as the control computer 12 in the main body IO of the apparatus, but
A personal computer may also be used. Further, although the alarm buzzer 15 and lamps 18 and 19 are used to issue a warning to the operator, the output signal from the alarm device 13 may be used to directly stop the machine. Further, when a plurality of detection sections 2 are to be judged by one judgment section, a multiplexer circuit may be incorporated in the judgment section and the detection signals may be successively compared.

(Effects of the Invention) According to the present invention, it is possible to provide a method for detecting an object using a fluorescent material, which detects an object with a good S/N ratio, automates the inspection process, and improves production efficiency. be. For example, as shown in the example, applied glue can be detected efficiently without the influence of ambient light, so it is possible to automatically inspect all products for gluing defects or the amount of glue at the same time as processing operations. It is possible to eliminate defects and improve productivity while maintaining high quality. In addition, since the equipment accurately performs inspections that were traditionally performed by humans, workers are freed from inspection work and there is no need to inspect all products in a separate process, significantly promoting labor and manpower savings. be effective.

[Brief explanation of drawings]

Fig. 1 is a diagram showing how a gluing failure detection device realizing the method of the present invention is used in a T-jointing machine, Fig. 2 is a diagram showing the positional relationship of the ultraviolet source and the detection part, and Fig. 3 is A diagram showing a block configuration of a circuit system of the gluing defect detection device, FIG. 4 is a structural diagram of a detection section, and FIG. 5 is a circuit diagram thereof. DESCRIPTION OF SYMBOLS 1... Ultraviolet source, 2... Detection part, 3... Analog signal amplifier, 1O... Device body, 11...-A/D conversion part, 12... Control computer, 13...・Alarm device, 14...Operation unit, 15...Alarm buzzer, 16
...Power switch, 17...Reset switch, 1
8.19...Lamp, 20A. 20B...roll, 21^, 22B...continuous paper,
23... Pin wheel, 24A, 24B... Hanging wheel, 40
... Light receiving section, 41.42 ... Photodiode, 4
3.44...Light reception feed, 50...Arithmetic circuit section,
51-53... operational amplifier, 54... amplifier.

Claims (1)

[Claims] In a method for detecting an object having a fluorescent light emitter, the detectable object is irradiated with ultraviolet rays and the fluorescence of the fluorescent light emitter is detected by a light receiving element, wherein at least two or more light receiving elements are provided, and each light receiving element is A method for detecting an object using a fluorescent light emitter, characterized in that the object to be detected is detected without being affected by ambient light or the like by subtracting the output value of .