JPH0120374B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field to which the Invention Pertains] The present invention relates to an article appearance inspection device that inspects the article based on sensor output obtained by scanning a cylindrical article such as a pharmaceutical capsule with an optical sensor. In particular, the present invention relates to an appearance inspection device with an improved storage method for storing sensor outputs.

[Prior art and its problems]

FIG. 1 is an external view of such a drug capsule. That is, the capsule 1 is composed of a cap 11 and a body 12, and the cap 11 is further provided with a locking hole (notch) 13 for locking the cap and the body 12 together. The capsule before being filled with a drug is called an empty capsule, and at this time the bonding force between the cap 11 and the body 12 is small, and they are in a so-called temporary bonded state as shown in FIG. After the empty capsule is filled with a drug, the cap 11 and body 12 are further pressed to form a fully bonded state with a strong bonding force, as shown in FIG. Capsules formed in this manner may suffer from various defects during manufacture. For example, a thin spot where the capsule wall thickness is partially thinned,
This is a hole, pinhole, etc. where this swing spot has become even larger. Among the manufactured capsules, there are loose products in which the cap and body are separated, twin caps in which the separated cap is recombined with the normal product body, and lock capsules in which the empty capsule is fully connected during capsule transportation. There may be cases where defective products called . Therefore, it is necessary to inspect empty capsules to eliminate defective products with the above-mentioned defects.

By the way, various methods can be considered for inspecting such a capsule, and for example, the following can be used.

FIG. 2 is a block diagram showing the configuration of the capsule inspection apparatus, and FIG. 3 is an explanatory diagram showing the relationship between the capsule transport mode and the sensor output waveform. In FIG. 2, 2 is an optical sensor that irradiates light onto a capsule and receives the reflected light, 3 is a binarization circuit that binarizes the sensor output at a predetermined level, and 4 is a data processing unit (CPU). and a determination circuit consisting of a memory, etc., and 5 is a controller. Incidentally, since the capsule is conveyed in the direction of the arrow by the conveying member 6 as shown in FIG. 3a while being rotated about its longitudinal axis as the rotation axis, The surface of each capsule is thus scanned. Such scanning is also called a helical scan, and the output waveform obtained by this helical scan is an analog waveform, for example, as shown in FIG. The capsule can be inspected by writing the data into the file and performing predetermined processing using the data processing device.

By the way, in such a system, 1) The transport direction of the capsule is not necessarily fixed, and as shown in Figure 3a, some capsules are transported with the cap side first, while others are transported with the body side first. There are things that are done.

2) It is important to increase the inspection throughput, and for this purpose, if the transport speed is constant, it is necessary to narrow the capsule arrangement interval d as shown in FIG. 3a.

3) Depending on the material of the capsule, both the cap and body may be transparent or opaque, or a combination thereof, but in that case, the signal level for binarization will be different, so countermeasures are required.

4) Although the conveyance speed is constant, there are some fluctuations.

There are various problems such as. For this reason, if all the determination circuits are configured in hardware, especially the above 1),
In order to deal with items 2) and 3), the circuit becomes extremely complex and the number of parts increases, so software processing is usually performed by a data processing device. In this case, the binarized data for one capsule is stored in a predetermined memory at appropriate intervals, and the stored contents are processed by software to make a determination, as is clear from Fig. 3b. To,
Most of the total testing time (T ₁ +T ₂ ) is spent on data acquisition time T ₁ , leaving only a small amount of time T ₂ for judgment time. Moreover,
As pointed out in item 2) above, this time tends to be reduced, which has the disadvantage that accurate determination cannot be made.

[Purpose of the invention]

This invention was made in view of these points,
It is an object of the present invention to provide a capsule inspection device that can secure enough time to determine whether a capsule is good or not.

[Key points of the invention]

The key point is that the sensor output, which varies from predetermined position to predetermined position according to the outer shape and surface shape of the capsule, is binarized at a predetermined level. 2
The determination time can be reduced by alternately repeating the operation of enabling the binary signal to be read from the other memory while the binary signal is being written to one memory each time the capsule passes. The key point is that it is possible to take a sufficiently long time (maximum, the total inspection time required for one capsule; in Fig. 3b, it corresponds to the sum of T ₁ and T ₂ ).

[Embodiments of the invention]

FIG. 4 is a configuration diagram showing an embodiment of this invention, and FIG.
The figure is a waveform diagram of each part to explain the operation of Fig. 4,
FIG. 6 is an explanatory diagram explaining the write and read operations of the memory, FIG. 7 is a waveform diagram explaining the timing of reading sensor output into the memory, and FIG. 8 is a partial storage mode of various signals in FIG. 7. FIG. 2 is a memory configuration diagram showing the.

In FIG. 4, 2 and 5 are the same optical sensors and controllers as in FIG. 2, 4' is a data processing unit (CPU), 21 ₁ and 21 ₂ are differentiators, and 22 ₁ to 22
₅ is a comparator, 23 ₁ to 23 ₄ are monostable multivibrators (hereinafter also simply referred to as monostable), 24 and 26 are bus changeover switches specially provided according to the present invention, 25 ₁ and 25 ₂ are also memories, and 27 ₁ , 27 ₂ , 27 ₁ ', 27 ₂ ' are data buses, and 28 is an AND gate.

Differentiators 21 ₁ , 21 ₂ and comparator 2 in Fig. 4
2 ₁ to 22 ₅ , monostages 23 ₁ to 23 ₄ , AND gate 28 and the like form a binarization circuit, and its operation will now be described with reference to FIG. Furthermore, as shown in _FIG .
It is assumed that 1 _{and 2} defective capsules are each inspected.

The capsules 1 ₁ and 1 ₂ are helically scanned by the sensor 2, and a signal a as shown in FIG. 5A is obtained. Here, a ₁ is the recess created by the notch 13, and a ₂ is the recess created by the hole 14.
From this signal a, four types of signals b, f, g and m are obtained as follows. First, the signal b is obtained by comparing the analog signal a with a predetermined level a _L (see FIG. 5 B) using the comparator 22 ₁ , and as shown in FIG. It's going to change. Signals f and g are the size of the field of view of the sensor and the transport speed of the capsule V _T
and the analog signal a by a differentiator 21 ₁ having a predetermined differential coefficient determined by the shape of the capsule.
After being differentiated, it is binarized by the comparators 22 ₂ and 22 ₃ at the levels C _H and _CL shown in _FIG . Depending on the beginning and end of the body and cap, the results are as shown in Figure 5 D and H, respectively. Note that the signals f and g are output from the comparators 22 ₂ and 22 ₃ to monostems 23 ₁ and 2
The reason for holding the signals for a predetermined _period of time will be described later. On the other hand, the signal m is obtained by differentiating the analog signal a using a differentiator ₂₁₂ having a predetermined differential constant determined by the size of the field of view of the sensor, the circumferential velocity of the capsule _VN , the shape of the defective part, etc. The signal h as shown in Fig. 5,
The comparators 22 ₄ and 22 ₅ set the predetermined level h _H ,
Signals i and j are obtained by comparing them with h _L respectively, and the AND gate 28 performs an AND operation on the signal k obtained through the monostage 23 ₄ that shapes this signal j into a signal of a predetermined width, and the signal i. The signal l is further shaped into a signal of a predetermined width by a monostage ₂₃₃ . Therefore, the signal l or m is the fifth
As shown in the figure, this is obtained only when a concavity such as _a1 exists in the analog signal a, and is not obtained in other cases. Here, the concave portion including the notch of the capsule is detected using the monoste 23 ₃ , 23 ₄ and the AND gate 28 , but the outputs i and j of the comparators 22 ₄ and 22 ₅ are shaped into signals of a predetermined width. It is possible to store the information in the memory and perform the detection inside the CPU 4'. The binary signal from the capsule thus obtained is, for example, from the Nth capsule ₁₁ shown in FIG.
6 is in the position indicated by the solid line in FIG. 4, those signals are stored in the memory ₂₅₁ . At this time, data regarding the N-1st capsule has been written in the memory ₂₅₂ , and therefore,
The CPU 4' determines the N-1st capsule based on this data, and sends the result to the controller 5.
send to Next, when scanning the N+1-th capsule ₁₂ as shown in FIG. 5, the controller 5 switches the bus selector switches 24 and 26 to the dotted line positions in FIG. is written to memory 25 ₂ while memory 25 ₁
is connected to CPU 4', so CPU 4' judges the Nth capsule.

Here, the timing of writing the binarized signal into the memory will be explained with reference to FIG. 7. In addition,
Figure 7A shows the sensor output a, Figure A' shows its partially enlarged waveform, Figure 7B shows the output of the AND gate 28 in Figure 4, and Figure C shows the output of the monoste ₂₃₃ in Figure 4. , Figure 2 shows the timing t. In particular, the interval between the timings t is the standard for the determination accuracy in the capsule length direction, but here, for example, the time required for the capsule to rotate 1/4 turn and equally chosen. Incidentally, the time width of the binary signal l as described above is determined by the size of the notch or hole in the capsule, but its value is approximately 1/10 or less of the time required for one revolution of the capsule. Therefore, since the signal l cannot be read at the read timing _shown in _FIG . It's something you make. Note that, according to this signal m, reading can be performed more than once as shown in FIG. This point also applies to the signals f and g. In this way, as shown in _{FIG .}
For example, in the case of FIG. 7, the 8th
It is stored as shown in the figure. 6A shows the operation of the memory ₂₅₁ , and FIG. 6B shows the operation of the memory ₂₅₂ , respectively.

Figures 9 and 10 are normal capsules 1 as shown in Figure 5.
FIG _{. 1} is an explanatory diagram for explaining the storage mode of signals b, f, g, and m obtained by scanning the perforated capsules 1 _{and 2} , respectively.

In FIGS. 9 and 10, the symbols shown at each address are attached as follows. That is,
CPIN1, 2 are the start and end addresses where the binary signal b becomes "1", RISE1, 2 are the addresses where the binary signal f becomes "1", CENTER-B,
C is the address near the center of the capsule, FALL1,
2 is the address where the binary signal g becomes "1", and the addresses near the beginning and end of the capsule are
NOTCH1 and NOTCH2 are addresses where the binary signal m becomes "1", which occurs in the area where the cap and body overlap, and HOLE is the address mentioned above.
These are assigned in correspondence with the addresses where the binary signal m becomes "1" in areas other than NOTCH. Note that Figure 9 shows the case of a normal product that is transported with the cap first, and Figure 10 shows the case of a defective product that has a hole in the body and is transported with the body first. It can be seen that in FIG. 9, the addresses indicating notches (NOTCH1, 2) appear earlier than in the case of FIG. 10, and the address indicating a hole (HOLE) does not appear.

Next, a description will be given of how the determination is made based on the information (signals b, f, g, m, etc.) extracted and stored as described above.

Here, the meanings of the signals b, f, g, and m are summarized as follows.

1) Regarding signal b: Becomes "1" when scanning a capsule or conveyance member.

2) Regarding the signal f, it becomes "1" when scanning the beginning of the capsule, the end of the capsule storage hole on the conveying member, or the cut end of the cap when the capsule is conveyed with the body first.

3) About signal g End of capsule, beginning of capsule storage hole,
Alternatively, if the capsule is transported with the cap first and the cap cut end is scanned, it becomes "1".

4) Signal m becomes "1" when scanning a concave part, a thin part, or a part with low reflectance on the capsule surface.

As described above, each signal has its own meaning, but it is not necessarily determined uniquely, and therefore it is necessary to further analyze these. That is, the signals f and g are generated near the beginning, end, or center of the capsule, but since their addresses are far apart from each other, they can be easily distinguished. However, since there are two types of signal m, one for a notch (NOTCH) and the other for a hole (HOLE), the distinction is made here as follows.

FIG. 11 is a flowchart illustrating a signal determination method.

First, as is clear from the above sections 2) and 3), by checking the address where the signal f or g becomes "1", the direction of transport of the capsule and the position of the cap cut are determined (see A and B). ). Next, check the address for which the signal m is "1" (see C and D), and if this address is on the cap side and is not more than a predetermined distance from the cap cut, the signal m = 1 is due to the notch. It is a thing,
On the other hand, if it is a predetermined distance or more away and is on the body side, it can be considered that it is due to a hole.
Therefore, here, f=1 representing the center position
Alternatively, determine whether the difference between the address where g = 1 and the address where m = 1 is smaller than a predetermined setting value CT ₁ (see E and F), and if YES, it is due to the notch and is normal. (see G), and if NO, it is determined that the product is defective because it has a hole (see H).
Note that in C and D, if there is no address for which m=1, it is determined as an error (see R and N).

Although the above description has mainly focused on inspecting the surface of a capsule, it is also possible to inspect twin caps, chipped caps, lock capsules, etc. as described above in the same way. In addition, in the embodiment shown in FIG. 4, the monoste 23 is
I am trying to set up ₄ , but this monoste 23 ₄
By connecting to the comparator 22 ₄ side instead of the comparator 22 ₅ , the convex portion of the analog signal can be detected. Moreover, if the unevenness of the analog signal is not to be distinguished, it is possible to omit the monoste.
Furthermore, as mentioned above, the comparators 22 ₄ and 22 ₅
directly memorizes the output of
4' may also be used.

〔Effect of the invention〕

As described above, according to the present invention, two memories are provided and the writing and reading of the binary signal are performed alternately, so that the data acquisition time and the calculation time are not separated. It can be used as calculation time. For example, the determination time when only one memory is used is approximately 20% or less of the capsule transport pitch time (T ₁ + T ₂ ) explained in FIG.
According to this invention, the determination time is approximately the same as this, that is, without reducing the processing capacity, the determination time can be reduced to 5.
It can be more than doubled. Furthermore, in this invention, all the binarized information for one capsule is stored, which not only makes it easier to judge by software, but also reduces the influence of conveyance speed. This has the advantage that it can be easily handled even if the conveyance directions vary.

The present invention can be widely applied not only to pharmaceutical capsules as described above, but also as an inspection device for similar articles in general.

[Brief explanation of drawings]

Fig. 1 is an external view showing the capsule, Fig. 2 is a block diagram showing the outline of the capsule inspection device, Fig. 3 is an explanatory diagram showing the relationship between the transport mode of the capsule and the sensor output waveform, and Fig. 4 is the present invention. FIG. 5 is a waveform diagram of each part to explain the operation of FIG. 4, FIG. 6 is an explanatory diagram to explain write and read operations of two memories, and FIG. A waveform diagram illustrating the relationship between the reading timing of the sensor output into the memory, FIG. 8 is a memory configuration diagram showing the partial storage mode of various signals, and FIGS. 9 and 10 are the various signals shown in FIG. 5. FIG. 11 is a flowchart showing part of a signal determination method. Code explanation 1, _{1 1} , 1 ₂ ... drug capsule, 1
1... Cap, 12... Body, 13... Notch, 14... Hole, 2... Optical sensor, 3... Binarization circuit, 4... Judgment circuit, 4'... Data processing unit (CPU) , 5...Controller, 6...Transporting member, 6 ₁ ...Capsule storage hole of the transporting member, 21 ₁ ,
21 ₂ ... Differentiator, 22 ₁ to 22 ₅ ... Comparator, 23 ₁ to 23 ₄ ... Monostable multivibrator (Monoste), 24, 26 ... Bus changeover switch, 27 ₁ , 27 ₂ , 27 ₁ ', 27 ₂ '...Data bus.

Claims (1)

[Claims] 1 An optical sensor that sequentially scans a substantially cylindrical article that is rotated about a longitudinal axis and conveyed in the axial direction; a signal extraction means for extracting a predetermined signal representing the shape of the surface; two storage means for storing the binarized signal for a predetermined time for each article; a switching means for switching so that when the signal is written in the storage means, the signal is read from the other storage means, and the switching means alternately switches between the two storage means for each article, thereby writing; Reading is performed alternately,
An appearance inspection apparatus characterized in that an article is inspected by performing a predetermined analysis based on the read binary signal.