JPS6318568Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a defective product detection device for detecting defective products in an automatic packaging line that arranges and packages products such as tablets, capsules, and confectionery in multiple lines on a film.

Conventionally, in this type of defective product detection device, a film made by packaging a plurality of detection objects in multiple rows is transported in a predetermined direction by a transport mechanism, and a large number of films arranged in a direction perpendicular to the transport direction are transported. An image sensor having a light-receiving element is provided, and when the image sensor detects an object, the output signal output is adjusted to the size of the object, the arrangement pitch of the object, etc. set in advance by adjusting a digital switch. Discrimination is made based on the discrimination criterion data of
In this way, defective products of the object to be detected are detected.

However, according to the above configuration, when the type of object to be detected wrapped in a film is changed, the digital switch is adjusted in advance each time, and the discrimination criterion data such as the size of the object and the arrangement pitch of the object is changed. Since the settings must be made, adjusting the digital switch is troublesome and requires skill, making it almost impossible for ordinary workers to make adjustments.

The present invention was developed in view of the above circumstances, and its purpose is to provide a defective product detection device that can reliably detect defective products by automatically following changes in the type of the detected object. It is in.

To summarize the present invention, an image sensor is provided which has a large number of light receiving elements arranged in a direction perpendicular to the film transport direction and sequentially extracts output signals from these large number of light receiving elements, and the output of this image sensor is A control circuit is provided that compares the signal and a reference signal and outputs a detection signal when they do not match, and furthermore, a reference signal is written into this control circuit by the output signal when the image sensor detects the sample object. Even if the type of object to be detected is changed, the output signal when the image sensor detects the sample object can be used to send a reference signal to the storage section of the control circuit. Defective products can be detected based on this reference signal, and when the operator adjusts the digital switch and sets discrimination criteria data such as the size of the detected object and the arrangement pitch of the detected object, Its distinctive feature is that it eliminates the need for tedious work.

An embodiment in which the present invention is applied to an automatic tablet packaging line will be described below with reference to the drawings. First, in FIG. 1, numeral 1 is a film roll formed by winding a film 2 made of vinyl chloride, and 3 is a transport roller which is a transport mechanism for transporting the film 2 from the film roll 1. This is, for example, a motor (not shown). Rotated by 4 and 5 are a pair of shaping rollers to which the film 2 is fed from the transport roller 3;
These shaping rollers 4 and 5 form pockets 6 ₁ and 6 on the film 2 for storing a plurality of tablets, for example, 10 tablets.
₂ ,..., ₆₁₀ (see Figure 4) are formed in a row. Therefore, as the film 2 is transferred, ten pockets 6 ₁ , 6 ₂ , . . .
6 ₁₀ are sequentially formed in multiple rows. 7 is a film 2 having pockets 6 ₁ , 6 ₂ , ..., 6 ₁₀
A tablet feeding device is installed above the film 2.
It is sequentially supplied to the pockets 6 ₁ , 6 ₂ , . . . , 6 ₁₀ in each row. On the other hand, 8 is an aluminum foil roll formed by winding aluminum foil 9, and 10 is a transfer roller for transferring the aluminum foil 9 from the aluminum foil roll 8, which is rotated by, for example, a motor (not shown). 11
12 and 13 are a guide roller, and 12 and 13 are a pair of sealing rollers. The film 2 and the aluminum foil 9 are tightly overlapped between the sealing rollers 12 and 13, and the film 2 and the aluminum foil 9 are heated by a high-frequency heating device (not shown). are heat fused. 14 to 16 are guide rollers, 17 is a slitter for making perforations in the film 2 and aluminum foil 9, 18 is a cutter for cutting the film 2 and aluminum foil 9, and 19 is a conveying device for conveying non-defective products. be. Well, 20
2 is an image sensor installed above the film 2 between the tablet feeding device 7 and the sealing rollers 12 and 13, and is located in a direction (direction perpendicular to the direction of arrow Y shown in FIG. 2) of the film 2. For example, a large number of cells arranged in a straight line in the direction of the arrow X shown in Figure 2
It is equipped with 2048 (2048 bits) photodiodes and other light-receiving elements (not shown), and is configured to perform optical scanning by extracting output signals from each of the 2048 light-receiving elements in time series. There is. A light projector 21 is provided to face the image sensor 20 with the film 2 in between, and a light projector 21a formed on the top surface of the light projector 21 extends in a direction perpendicular to the transport direction of the film 2, as shown in FIG. It has an elongated rectangular shape, and the film 2 passes through the image sensor field of view A formed by the light projector 21a and the image sensor 20.
The output signal Sa of the image sensor 20 is the third
As shown in the figure, it is input to the CPU 23 of the control circuit 22 and compared with a reference signal Sb input from the RAM 24, which is a rewritable storage section. This reference signal Sb
is the standard for determining whether the tablet a stored in the pockets 6 ₁ , 6 ₂ , ..., 6 ₁₀ of the film 2 is defective, and is the output signal Sa when the image sensor 20 detects the sample tablet a. Based on this, the CPU 23 calculates the discrimination standard data for the tablet a, and the calculation result is stored in the RAM 24 as the discrimination standard data corresponding to the reference signal Sb. Therefore, CPU23
The output signal Sa of the image sensor 20 input to
When the reference signal Sb of the RAM 24 and the reference signal Sb of the RAM 24 do not match, a detection signal is outputted from the CPU 23, an alarm is issued by an alarm generating device (not shown), and the detection signal is input to a shift register (not shown) to control the transfer device 19. The transport operation is controlled.
Reference numeral 25 denotes a rotary encoder, which is designed to apply one pulse to the CPU 23 of the control circuit 22 each time the film 4 is transferred a certain distance by the transfer roller 3. Reference numeral 26 denotes an operation panel, which includes a push button switch for learning the detection zone of the detected object, a push button switch for learning the discrimination criterion data for defective products of the detected object, and a push button switch for starting defective product detection for tablet a (both (not shown) are provided, and each signal is output by pressing each push button switch.
Sc, Sd, and Se are provided to the CPU 23 of the control circuit 22. Furthermore, the operation panel 26 is provided with a digital switch (not shown) for setting an allowable error value.

Next, a procedure for changing the type of tablet a to be packaged in the film 2 in the defective product detection apparatus having the above configuration will be described. The film 2 is transferred from the film roll 1 by the transfer roller 3 in advance, and ten pockets 6 ₁ , 6 ₂ , . . . , 6 ₁₀ are formed on the film 2 by the shaping rollers 4 and 5. Then, as shown in FIG. 4, a predetermined pocket (in this embodiment, pocket 6 ₁ ,
After storing sample tablet a in 6 ₂ and 6 ₆ ),
Push the push button switch for detection zone learning on the operation panel 26. Then, the CPU of the control circuit 22
The signal Sc is input to 23, which causes the CPU 23 to
A scanning command signal Sf is applied to the image sensor 20, and the image sensor 20 starts optical scanning in the direction of the arrow X. Detection signals Sa resulting from the optical scanning are sequentially applied to the CPU 23.
The detection zone B per pocket (one tablet A) is calculated and set based on the base pattern. That is, CPU2
3 is based on the detection signal Sa from the image sensor 20, and the bit that is shielded from light by the tablet a in the pocket ₆₁ and the bit that is shielded from the light by the tablet a in the pocket ₆₂ . Arrow X between a
In addition to calculating the dimension in the direction, the bit and pocket 6 that are shielded from light by the tablet a in pocket 6 ₁ are calculated.
The width dimension of the film 2 and the number of tablets a stored in one row are calculated based on the bits shielded from light by the tablets a in the pockets 6 1 , ₆ from the scanning start point C of the image sensor ₂₀ . The distances L ₀ , L ₁ , L ₂ , ..., L ₁₀ to the interline points of 6 ₂ , ..., 6 ₁₀ are set, and the arrangement pitch W ₀ of the tablets a is also set. is set and this detection zone B is stored in the RAM 24. In this case, the tablet a is stored in advance in the pocket 6 ₁ ′ adjacent to the pocket 6 ₁ , and after the tablet a in the pocket 6 ₁ has been optically scanned, it is stored in the pocket 6 in the adjacent row.
By the time the optical scanning of tablet a in ₁ ' starts again, CPU2
The arrangement may be such that the dimension between the tablets a and a in the direction of the arrow Y is calculated based on the number of pulses from the rotary encoder 25 inputted to the input terminal 3, and the arrangement pitch _W0 is thereby set. Thereafter, the tablet supply device 7 is operated to supply sample tablets a to any row of pockets 6 ₁ , 6 ₂ , . . . , 6 ₁₀ on the film 2, and the push button switch for learning discrimination criterion data is pressed. When a signal Sd is inputted to the CPU 23 of the control circuit 22 by pressing the button, the film 2 is transferred in the direction of the arrow Y, and each tablet a stored in the pockets 6 ₁ , 6 ₂ , ..., 6 ₁₀ passes through the field of view A of the image sensor. The projected area of each tablet a is detected by optical scanning by the image sensor 20 as it passes. In this case, the image sensor 20
The optical scanning of is controlled by the pulses of the rotary encoder 25, and the projected area of each tablet a is determined for each optical scanning of the image sensor 20 in the detection zone B (one time in FIG. 5), as shown in FIG. The light-shielding bits W ₁ , W ₂ , W ₃ ,
..., W _o is detected as the sum D (D=W ₁ +W ₂ +W ₃ +...W _o ). Then, the sum D corresponding to the projected area of each tablet a detected by the image sensor 20 as described above is sent to the CPU as an output signal Sa.
23, and the deviation between the maximum and minimum projected area of tablet a is calculated for each detection zone B, and if the deviation is within the error tolerance given by the digital switch, for example. Only tablet a
is considered to be good product data. Then, when a predetermined number of good product data have been collected, the average value of the projected area per non-defective tablet a is calculated, and based on this average value and the above-mentioned error tolerance (excess %, insufficient %), The upper and lower limits of the number of bits corresponding to the projected area of are set, and these upper and lower limits are stored in the RAM 24 as discrimination criterion data corresponding to the reference signal Sb.

After the discrimination criterion data is created as described above, when the push button switch for starting defective product detection is pressed, the defective product of tablet a is detected by the image sensor 20 and the control circuit 22 in the following manner. That is, as described above, the image sensor 20 detects the sum D of the number of light-blocking bits W ₁ , W ₂ , ..., W _o (see FIG. 5) for each scan of the image sensor 20 in the detection zone B. The output signal Sa corresponding to this sum D is sent to the CPU of the control circuit 22.
23, and this output signal Sa is a reference signal corresponding to the upper limit value and lower limit value stored in the RAM 24.
It is compared with Sb and determined as follows.

(i) When the output signal Sa and the reference signal Sb match (in the case of a non-defective product) In this case, lower limit value < D < upper limit value,
Tablet a is determined to be a good product and no detection signal is output.

(ii) When the output signal Sa and the reference signal Sb do not match (defective product, such as a missing tablet, a missing tablet, or two tablets mixed in the same pocket) In this case, lower limit value > D, D > upper limit value. , tablet a is determined to be defective and CPU2
A detection signal is output from 3, and this detection signal causes an alarm generator (not shown) to issue an alarm, and the detection signal is also input to a shift register (not shown), whereby the defective part is cut off by the cutter 18. When this occurs, the conveying device 19 is rendered inoperative and the defective product portion falls and is discharged from the cutter 18 portion.

Although the above-described defective tablet a detection operation is performed for each tablet, the cutter 18 discharges one or more rows containing the defective tablet a as a defective product.

According to this embodiment, the following effects can be obtained. That is, the control circuit 22
Since it is composed of a CPU 23 and a RAM 24, the upper and lower limits of the number of bits corresponding to the detection zone B and the projected area of a good product can be determined based on the output signal when the image sensor 20 detects the sample tablet a. The reference data is calculated by the CPU23.
It can be stored in the RAM 24, and as a result, even if the type of tablet a is changed, there is no need to adjust the digital switch and reset the discrimination criterion data as in the past, which is a cumbersome and highly skilled work. , even ordinary workers can prepare tablets without any adjustment work.
It becomes possible to switch the product type. Furthermore, since the projected area of the tablet a is detected for each tablet by the image sensor 20 and the detected value is compared with the discrimination criterion data stored in the RAM 24, defective tablets a can be reliably detected. In particular, in this example,
Since the rotary encoder 25 is provided to detect the transport speed of the film 2, one output pulse is sent to the control circuit 22 each time the film 2 is transported a certain distance.
is now given to CPU23, and as a result,
Even if the transport speed of the film 2 is changed, the image sensor 20 can perform optical scanning by automatically following the change in speed.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the invention, for example, the object to be detected may be a capsule, a confectionery, etc.

As is clear from the above description, the present invention stores the reference signal in the storage section of the control circuit using the output signal when the image sensor detects the sample object even when the type of object to be detected changes. I was able to do it.
A defective product detection device can now detect defective products based on this reference signal, and as a result, it can automatically follow the switching of objects to be detected and detect defective products. can be provided.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a diagram showing the overall schematic configuration, Fig. 2 is a perspective view of the main parts, Fig. 3 is a block diagram showing the electrical configuration, and Fig. 4 is a diagram showing the overall configuration. FIG. 5 and FIG. 5 are diagrams for explaining the operation. In the figure, 2 is a film, 3 is a transfer roller (transfer mechanism), 20 is an image sensor, 21 is a projector, 2
2 is a control circuit, 23 is a CPU, 24 is a RAM (storage unit), and 25 is a rotary encoder.

Claims (1)

[Scope of utility model registration request] A transfer mechanism that transfers a film formed by packaging a plurality of detection objects in multiple rows in a predetermined direction, and a plurality of transfer mechanisms arranged in a direction perpendicular to the transfer direction for the film transferred by the transfer mechanism. The image sensor has a plurality of light-receiving elements and sequentially extracts output signals from the plurality of light-receiving elements, and a control circuit that compares the output signal of the image sensor with a reference signal and outputs a detection signal when they do not match. The defective product detection device is characterized in that the control circuit has a rewritable storage section in which a reference signal is written in accordance with an output signal when the image sensor detects a sample detection object.