JPS6339261B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to an apparatus for inspecting the appearance of solid preparations such as pharmaceutical preparations such as tablets and capsules or pellet-shaped preparations for other uses to determine their quality. This invention relates to an abnormal load detection device.

In order to provide an understanding, the functions of the entire solid preparation testing apparatus shown in FIG. 1 will be briefly explained.

The tablets 1 accommodated in the hopper 2 are once supplied to the first drum 3. More specifically, as shown in FIG. 3, the first drum 3 is a hollow cylindrical container having a plurality of receiving holes 31 passing through it at regular intervals along the circumferential direction, and is rotated in the direction of the arrow. As the drum rotates, the tablets 1 are filled into the accommodation holes 31 one by one and transported upward. At this time, the outer guide plate 32 prevents the tablet 1 from falling from the accommodation hole 31. A second drum 4 that rotates in the opposite direction to the first drum 3 is arranged adjacent to it.
When the transferred tablet 1 reaches a position where the first drum 3 and the second drum 4 come into contact, the tablet 1 is transferred from the first drum 3 to the second drum 4 at that position. As shown in Fig. 3, the transfer method is to create a negative pressure fixed chamber 43 in the second drum 4, which is evacuated by a sliding sealing method or the like, and has a size slightly more than half the circumference of the drum. Vacuum suction holes 42 passing through the bottom of countersink holes 41 bored at equal intervals on the outer periphery of the drum are provided, and the tablets 1 from the first drum 3 are sucked into the countersinks 41 and transferred to the second drum 4 side. At this time, the accommodation hole 31 of the first drum 3 and the countersunk hole 41 of the second drum 4 are aligned.

The tablets 1 transferred to the second drum 4 in this manner have a countersunk hole 51, a vacuum suction hole 52, and a vacuumed fixing chamber 53, having the same configuration as the second drum 4.
It is transferred to a third drum 5 adjacent to the second drum 4 and rotating in the opposite direction to the second drum 4 . In this case, the side of the tablet 1 opposite to the second drum 4 is turned to the front side. For example, when the tablet 1 transferred by the second drum 4 comes directly above the drum, the xenon lamp 7 is ignited and the first observation device 6 (for example, an industrial television camera) observes one surface of the tablet 1. Capture images instantly. Similarly, when the tablet 1 is directly under the third drum 5, the xenon lamp 9 is ignited, and the second
The other surface is instantaneously imaged by an observation device 8 (for example, an industrial television camera). Naturally, there is a time lag between the times at which the same tablet is observed by the first observation device 6 and the second observation device 8, so the number of holes corresponding to the holes drilled in the drum can be determined by, for example, a shift register or a regular As shown in FIG. 2, the quality determination signal is stored via the RAM and is determined by the quality determination signal by the surface determination device 14 captured by the second observation device 8 and the quality determination signal by the surface determination device 15 captured by the first observation device 6. The output of the discriminating device 15 is matched by reading the final stage through the shift register 16, and the comprehensive discriminating device 17 determines whether the tablet is finally a good product or a defective product based on the quality determination signals of both. For example, using a discharge mechanism such as an air blowing nozzle (not shown), if the product is good, it is transferred to the good product tank 13 via the good product transfer pipe 12.
The defective products are sorted and transported to a defective product tank 11 via a defective product transfer pipe 10.

By the way, as mentioned earlier, tablets 1 are placed in each drum 3,
In a conveying device that transports the first container from the supply section to the discharge section while being stored and held in the accommodation holes 31 or countersinks 41 and 51 arranged on the outer circumferential surface of the first
As mentioned in the figure, tablets 1 are stored in each collection tank 11,
Failure of the ejection mechanism for the tablet 1 ejected toward the tablet 13;
If, due to a mistake in the ejection operation, the tablet 1 is not ejected into the transfer pipes 10, 12 and is transferred while adsorbed to the third drum 5, the tablet bypasses the upper surface area of the third drum 5 and goes around the third drum 5. , it returns to the transfer position with the second drum 4 again. On the other hand, since subsequent tablets are continuously transferred from the second drum 4 to the third drum 5 at this transfer position, a situation occurs in which the tablets engage with each other in the countersink 51. This transportation trouble in which tablets get stuck during transportation is called jamming.

When such jamming occurs, it not only destroys the tablet, but also causes the broken tablet powder to scatter and degrade the inspection function of the visual inspection device. Therefore, when jamming occurs, it is immediately detected. Before the damage becomes more widespread, it is necessary to emergency stop the conveyance device and repair the problem by removing the jamming tablets or cleaning the drum-shaped conveyance section. An excellent method for detecting the occurrence of such jamming and making an emergency stop has been previously applied for and has already been put into practice. In order to gain understanding, the general structure and operation and effects will be explained. The first to third drums 3, 4, and 5 shown in FIG. 4 are connected to a drive motor 60 via a pulley 62 directly connected to the motor and a timing belt 71, and the driving torque of the drive motor 60 is directly connected to each drum. It is configured to rotate in the direction of the arrow. The drive motor 60 and the drum-shaped conveyance section are connected via a constant torque transmission mechanism 70 as shown in FIG. The driving force of the drive motor 60 instantly,
In addition to isolating the inertial force, it is configured to brake and stop in response to a signal from a sensor 44 shown in FIG. 3 that detects the change in the rotational speed of the drum-shaped conveyance section that occurs at that time. The constant torque transmission mechanism 70 is connected to the motor shaft 61 as shown in FIG.
A circular arc groove 64 that is directly connected to the board and runs along the circumferential direction of the plate surface.
and a pulley 62 as a driven member whose one end is rotatably fitted onto the motor shaft.
The connecting pin 65 is attached and fixed to the arcuate groove 64 and loosely fitted into the arcuate groove 64, and the connecting pin 65 and the driving plate are locked by locking both ends to the locking pin 66 implanted in the connecting pin 65 and the driving plate 63, respectively. Board 63
and a torque transmitting torsion spring 67 stretched between the two. Note that the symbol B indicates the rotation direction of the drive motor 60. In particular, the torque transmitting torsion spring 67 is applied to the connecting pin 65, and thus to the pulley 62, to a value slightly larger than the required load torque corresponding to the required load torque of the drum-shaped conveying sections 3, 4, 5 during steady operation. The structure is flexed and stretched to absorb the torsional moment. In this way, each drum 3, 4, 5
During steady operation of the conveying device, each drum 3, 4, 5 is moved at the same feed rate as the drive motor 60 while the connecting pin 65 is pressed against the right end of the arcuate groove 64 due to the torsional moment of the torsion spring 67. It is rotationally driven. In this state, an abnormal load is applied to the drum-shaped conveying section due to trouble such as jamming, and the load torque at that time is applied to the torsion spring 67.
When the transmission torque exceeds the transmission torque setting value set as the torsional moment value, the connecting pin 65 immediately separates from the right end of the arcuate groove 64 and lags behind the rotation of the drive plate 63. This operation causes the drive motor 6
The equivalent inertial force of 0 does not act on the jamming generating cylinder on the drum side, and only the relatively small inertial force of each drum 3, 4, 5 interconnected by the timing belt 71 acts on it. By disconnecting the inertial force of the drive motor 60 in this way,
Excessive impact force is prevented from being applied to the location where jamming occurs, thereby preventing further damage to the tablets and the components of the conveying device. At the same time, due to the intervention of the constant torque transmission mechanism 70, the inertial force of the drive motor 60 is disconnected from the drums 3, 4, 5 when jamming occurs. This appears as a decrease in the rotational angular velocity. In addition to this, the drum rotational angular velocity detection mechanism described below easily and quickly detects the occurrence of an abnormal load such as jamming, and immediately brakes and stops the drive motor 60 based on the signal. That is, one of the drums 3, 4, and 5 shown in FIG.
For example, the inner periphery of the drum 4 is positioned so that the light emitting element 45 and the light receiving element 46 of the sensor 44 correspond to the rows of countersinks 41 arranged on the outer peripheral surface of the drum 4. and are installed facing each other on the outer circumferential side. In other words, the countersunk hole 41 and the vacuum suction hole 42 form a hole that penetrates both the inside and outside of the drum 4, so the sensor 44
The light emitting element 45 and the light receiving element 46 are optically coupled through the penetrating hole. Therefore, the sensor 44 functions as a passage detector whose detection holes include a plurality of countersunk holes 41 and vacuum suction holes 42 provided at equal intervals on the outer peripheral surface of the drum. The output waveform of this sensor 44 is shown in FIG. 6, and a pulse signal 48 representing passage through each hole is obtained by differentiating the rising portion of the output waveform 47 when passing through each hole. As is clear from FIG. 6, compared to the time interval t ₁ of the passing pulses 48 obtained during steady operation, the rotational speed of the drum decreases when jamming occurs, so the time interval t 2 of the passing pulses 48 is larger than t _{1 .}
Changes to The countersinks 41 of the tablets 1 are arranged at relatively narrow intervals on the drum circumferential surface, so by constantly monitoring the passing pulses 48, even slight changes in rotational angular velocity can be detected with high sensitivity. .
Thus, if the time interval of the passing pulse signals obtained by this detection mechanism 44 becomes larger than a certain predetermined value, it is determined that the rotational angular velocity of the drums 3, 4, 5 has decreased, that is, trouble such as jamming has occurred, and the drive motor is immediately stopped. 60 is brought to an emergency stop by appropriate braking means. As the braking means, in addition to well-known mechanical braking means, electrical braking means such as DC excitation braking and eddy current braking are effectively used.

In addition, when stopping the braking described above, if the load torque due to jamming, that is, the rotational resistance is very large and each drum 3, 4, 5 is stopped immediately, the rotational inertia of each drum 4, 5, 6 is applied to the drive motor. 60 does not act as a braking load, and the connecting pin 65 in the constant torque transmission mechanism 70 stops while remaining apart from the right end of the arcuate groove 64. On the other hand, if the increase in load torque caused by jamming is small, the connecting pin 65 and the right end of the arcuate groove 64 will temporarily separate from each other at the instant jamming occurs, but they will come into contact again. A part of the rotational inertia of each drum acts as a braking load on the drive motor 60, and the drive motor 60 is suddenly stopped.

By the way, since the above-mentioned emergency stop device detects a change in the rotational speed of the drum-shaped conveyance section when an abnormal load occurs, there is a possibility that the speed of the drum-shaped conveyance section changes for some reason while it is rotating. An abnormal load is detected. Therefore, it is not possible to distinguish between a change in conveyance speed and an abnormal load, and the problem of being able to detect an abnormal load separately from a change in conveyance speed remains unsolved.

From this perspective, the present invention aims to solve the above-mentioned unresolved problems.

According to the present invention, the drive motor is connected and inserted between the drive motor and the drum-shaped conveyance section, and the transmission torque is set to a value corresponding to the required load torque of the drum-shaped conveyance section during steady operation. A constant torque transmission mechanism that disconnects the inertia force of the drive motor when a load torque larger than the specified value is applied, a detection mechanism that detects the rotational angular velocity of the drum-shaped conveyance section, and a speed detection mechanism that detects the rotational speed of the drive motor. and a braking means for the drive motor, and counts the number of output conversion pulses of a speed detection mechanism that detects the rotational speed of the drive motor until the rotational angular velocity detection mechanism of the drum conveying section outputs the next output. In comparison, this is achieved by stopping the drive motor when there is a larger change in the number of pulses counted than normal.

The configuration and effects thereof will be explained in detail below with reference to the drawings. We will omit the explanation of the parts that overlap with the abnormal load emergency stop device already described, and will describe the different parts of the device that makes an emergency stop of the drive motor when an abnormal load such as jamming occurs in the solid preparation conveying device.

The abnormal load emergency stop device according to the present invention is also inserted between the drive motor 60 and the drum conveyance section as shown in FIG. 7 in the same manner as in FIG. A constant torque transmission mechanism 70, which is set to a value corresponding to the required load torque of the motor and acts to disconnect the inertia force of the drive motor when a load torque larger than the transmission torque setting value is applied, is shown in FIG. A detection mechanism for detecting the rotational angular velocity of the drum-shaped conveying section, that is, a detection mechanism that corresponds to a row of countersink holes 41 arranged on the outer circumferential surface of the drum, and through holes penetrating the inside and outside of the two drums together with the countersink holes 4 and vacuum suction holes 42. Optical sensor 4 for optical coupling
A light emitting element 45 and a light receiving element 46 of No. 4 are arranged facing each other on the inner and outer circumferential sides of the drum. The difference is that in addition to the constant torque transmission mechanism 70 and the rotational angular velocity detection mechanism 44 of the drum-shaped conveyance section, the rotational speed of the drive motor 60 and the rotational speed of the drum are changed during steady operation or variable speed operation when no abnormal load such as jamming occurs. Since the rotational speeds of Nos. 3, 4, and 5 are in a constant relationship, No. 7 is used as a means for checking the relationship between the rotational speed of the drive motor 60 and the rotational speed of the drum-shaped conveyance section by comparing it with the case of an abnormality. As shown in the figure, a well-known tachometer generator (hereinafter abbreviated as tachometer generator) 60A is attached to the shaft 61 of the drive motor.
is installed. The rotational speed of the drive motor 60 is changed to a pulse waveform 60 of the output 60 waveform 60a shown in FIG.
0b, and the number of tachometric pulse waveforms 60b inputted between a rising pulse signal obtained by differentiating the output waveform from the optical sensor 44 and the next rising pulse signal is counted. In this case, even if the rotational speed of the drive motor 60 is changed, the number of pulse counts should remain constant because the output of the sensor 44 also changes. That is, as shown in FIG. 8b, the output waveform 60a1 of the tachometer 60A and the output waveform ₄₄ of the sensor 44 change in proportion to the speed change of the drive motor 60.
The periods of _a1 both change, and the relationship established between the output of the tachogenerator 60A and the period of the optical sensor 44 does not change. However, when an abnormal load such as jamming is applied, the torque of the drive motor 60 is absorbed by the torsion spring 67 as described above, and the output of the tachogenerator 60A, that is, the number of output conversion pulses, remains unchanged as shown in FIG. 8c. However, the output waveform from the optical sensor 44 is extended, and a time difference occurs between one rising converted pulse and the next rising converted pulse, and the number of tachogenene pulses counted during that period increases. Based on the above-mentioned premise, the present invention is based on a counter circuit 8 consisting of a known electronic circuit as shown in FIG.
2, the output waveform of the Takogiene 60A is first passed through the pulse conversion circuit 80 and then inputted to the counter circuit 82 for counting, and the count number is differentiated from the output waveform of the sensor 44 to generate a rising pulse signal by the rising pulse signal conversion circuit 81. 44b, 44b
Counter circuit 8 using 1,44b2 as a clear signal
This is introduced as the second reset input.

In this manner, the number of pulses from the tachogenerator sent between the pulse signals of the sensor 44 during normal speed operation or variable speed operation is counted, and this value is determined in advance as a reference value. This reference value and the actually counted value are compared via a comparison circuit or the like. When the actually counted value greatly exceeds the reference value, it is determined that an abnormal load has occurred, and the output signal immediately activates the drive motor 6.
0 to an emergency stop using appropriate braking means.

Note that when the reference value is exceeded by a wide margin, it is considered as an abnormal load, and this is distinguished from the case where an abnormality occurs by providing a margin in consideration of the possibility that the count number may slightly exceed due to a counter error or voltage fluctuation.
However, it is also possible to provide a means for detecting even slight overages in a row and determining the cause thereof.

As described above and understood from the drawings, according to the present invention, the torque of the drive motor 60 is transmitted to the drum-shaped conveying section via the constant torque transmission mechanism 70, and a tachogenerator 60A is installed to detect the rotational speed of the drive motor. At the same time, some of the drums in the drum-shaped conveyance section are equipped with sensors for detecting the rotational angular velocity, and the number of converted pulse signals from the tachogenerator is counted in one pitch between the rising pulse signal of the output waveform of the sensor and the next rising pulse signal. The number of counts during normal operation is used as a reference value in advance, and this reference value is compared with the value counted during actual load operation.When the reference value is exceeded by a wide range, it is determined that the load is abnormal and the drive is started. to stop the motor,
Abnormal loads are detected not by changes in the rotational angular velocity detection mechanism itself attached to the drum-shaped conveyance unit, but by relative changes in the tachodynamic output attached to the drive motor, making it possible to clearly distinguish between changes in the speed of the drive motor. Separately, only abnormal loads can be detected.

In the explanation, we have described a visual inspection device for solid drug preparations, but it is not only possible to detect abnormal loads on such drum-shaped conveyance units, but also to independently detect the speed of the conveyance unit itself in various conveyance devices that use motors as drive sources. If it is a mechanism, it can be applied to all kinds of fields, such as stopping the drive source when there is a large change by comparing the detection mechanism with the tachodynamic output attached to the drive motor.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a visual inspection device for solid preparations, Fig. 2 is a block diagram showing a circuit system for visual inspection, Fig. 3 is a sectional view of main parts of a drum-shaped conveyance section, and Fig. 4 is a sectional view of a main part of a drum-shaped conveyance section. 5A and 5B are side sectional views and front views of the constant torque transmission mechanism, FIG. 6 is a time chart showing the output waveform of the rotational angular velocity detector provided in FIG. 3, and FIG. The figure is a side cross-sectional view of the drive motor with the constant torque transmission mechanism and tachometer generator attached, and Figures 8a, b, and c show the relationship between the output waveform of the tachometer generator and the output waveform of the rotational angular velocity detector in different states. FIG. 9 is a block diagram showing the circuit system of the abnormal load emergency stop device according to the present invention. Identical and corresponding parts in FIGS. 1 to 9 are designated by the same reference numerals. 3...First drum, 4...Second drum, 5...
Third drum, 44... Rotation angular velocity detection mechanism, 45
... Light emitting element, 46 ... Light receiving element, 60 ... Drive motor, 61 ... Drive motor shaft, 62 ... Pulley, 63 ... Drive plate, 64 ... Arc groove, 65 ...
Connection pin, 66... Stopping pin, 67... Torsion spring, 70... Constant torque transmission mechanism, 71... Timing belt, 60A... Tachometer generator, 80... Pulse conversion circuit, 81... Differential circuit (clear) signal generation circuit), 82...counter.

Claims (1)

[Claims] 1. A drum-shaped conveying section consisting of a plurality of drums driven by a drive motor, the drum-shaped conveying section having accommodating holes or holes for solid preparations arranged at predetermined intervals along its outer peripheral surface, and the accommodating holes In a device that transports solid preparations while holding them in holes or holes, the drive motor is connected and inserted between the drive motor and the drum-shaped transport section, and the transmitted torque has a value corresponding to the required load torque of the drum-shaped transport section during steady operation. a constant torque transmission mechanism that operates to disconnect the inertia force of the drive motor when a load torque larger than the transmission torque setting value is applied, and a detection mechanism that detects the rotational angular velocity of the drum-shaped conveyance section; The apparatus includes a speed detection mechanism for detecting the rotational speed of the drive motor and a braking means for the drive motor, and detects the rotational speed of the drive motor that occurs between adjacent pulses in the output pulses from the rotational angular velocity detection mechanism of the drum-shaped conveyance section. A solid drug conveying device characterized by counting the number of output pulses of a speed detection mechanism and stopping a drive motor when this count value exceeds a predetermined set value larger than the number of pulses counted during normal operation. Emergency stop device in case of abnormal load.