JPS599447B2 - Emergency stop device in case of abnormal load on solid drug transport equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applied, for example, to a visual inspection device for solid preparations, and is applicable to pharmaceutical tablets, capsules, or other pellet-like preparations (hereinafter referred to as "solid preparations"). When an abnormal load is applied to a conveyance device that uses a drum-shaped conveyance unit to convey solid preparations (generally referred to as ``-'') due to a trouble in conveying solid preparations, this is immediately detected and the conveyance device is immediately stopped. Regarding equipment.

First, the external appearance of the solid preparation conveying apparatus shown in FIG. 1 will be explained.

In the figure, 1 is a supply hopper for solid preparations (hereinafter referred to as "tablets" as an example), 2 is a drum-shaped conveying section (hereinafter referred to as "supply drum") constituting the supply section, and 3 and 4 are first and second hoppers, respectively. 2 one drum-shaped conveyance unit (hereinafter referred to as the “first drum”)
and "second drum") 5 and 6 are the first drum 3
, first and second tablet observation devices using, for example, industrial cameras, disposed close to the outer peripheral surface in the upper and lower top regions of the second drum 4; A determination device consisting of a discrimination circuit, a collection tank for defective tablets that are determined to be defective based on the 8-Pa judgment result and are sorted and discharged from the middle of the conveyance route, and a collection of good tablets that are carried out from the end position of the 9-Pa conveyance route. Tank 10 is a tablet.

The detailed structure of the conveying device, which is composed of the supply drum, first and second drums, etc. in FIG. 1, is as shown in FIG. 2.

In the figure, the supply drum 2 has holes 11 for storing tablets, which are through holes arranged at predetermined intervals on the outer peripheral surface of the drum, and the inner space of the drum is used as a tablet storage chamber 12.
A chute from the hopper 1 shown in the figure is opened.

On the other hand, in the first and second drums 3 and 4, pocket-shaped tablet accommodation holes 13 are arranged on the outer peripheral surface at equal pitches to the accommodation holes 11 of the supply drum, and each of the accommodation holes 13/
ri through the vacuum suction hole 14 to the first and second drums 3, 4.
It communicates with a vacuum chamber 15 defined inside the
It is configured to hold the tablet 10 by vacuum suction.

As shown in the figure, the drums 2 and 34 are arranged side by side so that their outer peripheral surfaces face each other, and are driven to rotate synchronously in the direction of arrow A with the phases of the accommodation holes 11 to 13 aligned. .

Further, an outer guide 16 is installed in the outer peripheral area of the lower surface of the supply drum 2 so as to cover the outer peripheral surface of the drum 2 .

This guide 16 is for guiding the tablets 10 filled in the through-hole 11 to prevent them from falling downward, and the tip thereof faces toward the position where the drums 2 and 3 meet. It is extended.

In the above configuration, the storage chamber 1 of the supply drum 2 is
The tablet 10 introduced into 2 is passed through the through-accommodating hole 11 from here.
As the drum rotates, it slides on the guide 16 and is guided upward to the upper right.

When the tablet 10 reaches a position facing the first drum 3, it is adsorbed and transferred from the through-accommodation hole 11 to the accommodation hole 13 of the first drum 3, and then in the process of being conveyed on the upper surface area of the first drum 3. The television camera 5 observes one half of the surface.

Further, the image is transferred between the first drum 3 and the second drum 4 in the same way, and the surface of the other half is observed by the television camera 6.

The tablets 10 are determined to be good or bad based on the above two observation results, and the tablets 10 determined to be defective are transferred to the defective product tank 8 in FIG. It is used to sort and discharge.

Incidentally, the drive mechanism of the above-mentioned conveying device can be constructed as shown in FIG.

A toothed pulley 17 is connected to each of the drums 2, 3, and 4, and a timing belt 18 with teeth on both sides is stretched across each pulley 17. A pulley 20 is engaged.

Note that the drive motor 19 is equipped with a reduction gear mechanism.

With the above configuration, by driving the drive motor 19, each drum 2, 3, 4 is connected to the arrow A through the timing belt 18.
It is synchronously rotated in the direction.

By the way, in the conveyance device that transports the tablets 10 from the supply section toward the discharge end while holding them in the accommodation holes 11 to 13 arranged on the outer peripheral surface of each drum as described above, for example, as described in FIG. If the tablet 10 is transferred without being ejected while being adsorbed to the second drum 4 due to a malfunction in the tablet ejection mechanism that ejects the tablet toward the recovery tank or due to an error in the ejection operation, the tablet 10 is transferred to the second drum 4 without being ejected. It detours around the upper surface area and returns to the transfer position with the first drum 3 again.

On the other hand, since subsequent tablets are continuously transferred from the first drum 3 to the second drum 4 at the transfer position, a situation occurs in which the tablets engage with each other within the accommodation hole 13.

Also, if the transfer posture of the tablets transferred to the first drum 3 or the second drum 4 is disturbed and the tablets stand upside down or protrude from the accommodation hole 13 and become tilted, the TV camera 5, 6 or other A situation occurs in which the tablet gets caught in a component close to the outer peripheral surface of the drum.

The transport trouble in which tablets get caught during transport is referred to as jamming.

When such jamming occurs, not only is there a risk of the tablet being destroyed, but also the visual inspection equipment may be affected by the scattering of the broken tablet powder, causing the inspection function to deteriorate. Therefore, when jamming occurs, it must be detected immediately. However, there is a demand for an emergency stop of the conveying device before the damage becomes more extensive, to facilitate recovery from the failure, such as by removing jammed tablets or cleaning the drum-shaped conveying section.

As a method for detecting the occurrence of jamming and making an emergency stop, the number of rotations of the drum in the conveyance device or the drive torque is monitored as a detection signal, and when an abnormal load occurs due to jamming, the drive motor is braked based on the detection signal. Attempts have been made to stop the transport drum or to disconnect the transport drum from the drive motor using a clutch mechanism.

That is, when jamming occurs, the load torque increases rapidly in an instant, resulting in a decrease in the rotational speed or an increase in the drive torque of the drive motor.

Therefore, it is theoretically possible to detect the occurrence of jamming by constantly monitoring the rotational speed or driving torque.

However, in the conventional drive mechanism, as shown in FIG. 3, each drum 2, 3, 4 is connected to a drive motor 19 via a pulley 20 directly connected to the motor and a timing belt 18, for example.
The drive torque of the drive motor is directly transmitted to the drum.

For this reason, in addition to the inertial force of each drum, the inertial force of the drive motor 19 is also applied to the location where jamming occurs.

In particular, the drive motor 19 is usually equipped with a reduction gear mechanism,
Even if the moment of inertia of the rotor of the motor itself is small, the equivalent inertial force of the drive motor viewed from the drum side in the operating state acts as a large value proportional to the square of the feed reduction ratio.

As a result, when jamming occurs with the conventional drive mechanism, the large inertia force mentioned above is applied, and the decrease in rotational speed appears with a time delay, and furthermore, changes in rotational speed can be easily detected. By the time the jamming is reduced to a certain level, excessive force will be applied to the jamming location, and damage such as pill breakage will be magnified before the drive motor stops braking, making it impossible to provide practically satisfactory protection. There was a drawback that it did not work properly.

A method that detects an increase in the drive torque when severe jamming occurs and disconnects the drive motor using, for example, an electromagnetic clutch, is possible if it is possible to quickly detect an increase in the drive torque, then disconnect the drive motor. This is preferable in that the inertial force of the motor is not applied to the jamming location, and therefore the impact load applied to the jamming location can be suppressed to a small level.

However, this not only complicates the language device provided with means for detecting an increase in drive torque, but also is disadvantageous in terms of cost because it also uses an expensive electromagnetic clutch.

The present invention has been developed in consideration of the above points, and when an abnormal load occurs due to jamming or other solid drug transport trouble, this invention is quickly detected and the transport device is brought to an emergency stop. It is an object of the present invention to obtain a novel emergency stop device that can prevent the inertial force of the motor from acting and minimize damage9. and the load side of the drum-shaped transfer section are connected via a constant torque transmission mechanism, and when an abnormal load exceeding the load torque during normal operation is applied due to jamming, etc., the drive motor is instantly switched off. In addition to separating the driving force and inertia force,
The gist of the present invention is that the drive motor is configured to brake and stop by detecting a change in the rotational angular velocity of the drum-shaped conveyance section that occurs at that time.

Next, the configuration and operation of the present invention will be explained in detail based on illustrated embodiments.

First, as shown in FIGS. 4a and 4b, the constant torque transmission mechanism 2 according to the present invention is connected and inserted between the drive motor 19 and the pulley 20.
Let's talk about 1.

The mechanism 21 includes a drive plate 24 that is directly connected to the motor shaft 22 and has an arcuate groove 23 along the circumference on the plate surface, and a pulley as a driven member whose one end is rotatably fitted onto the motor shaft. The connecting pin 25 is attached and fixed to the connecting pin 20 and is loosely fitted into the arcuate groove 23, and the connecting pin 25 is attached at both ends to the connecting pin 25.
, and a torque transmitting torsion spring 26 stretched across the lotus knot pin 25 and the drive plate 24 by being engaged with a stop pin 24a installed in the drive plate 24.

Note that the symbol B indicates the rotation direction of the drive motor 19.

In addition, in particular, the torque transmission spring 26 and the connecting pin 25, that is, the pulley 20, are
, 3 and 4, and is stretched so as to be flexed so as to apply a torsion moment of a value slightly larger than the required load torque.

Next, the operation of the constant torque transmission mechanism 21 will be explained in conjunction with FIGS. 2 and 3.

During steady operation of the conveying device consisting of the drums 2, 3, and 4, the connecting pin 25 remains pressed against the right end of the arcuate groove 23 due to the torsion moment of the spring 26.
3 and 4 are driven to rotate at the same speed as the drive motor 19.

In this state, if an abnormal load is applied to the drum-shaped conveyance section due to trouble such as jamming, and the load torque at that time exceeds the transmission torque setting value set as the torsion moment value of the spring 26, the connecting pin 25 (/ 'i immediately leaves the right end of the arcuate groove 23 and lags behind the rotation of the drive plate 240.

Due to this operation, the equivalent inertial force of the drive motor 19 does not act on the jamming location on the drum side, and only the relatively small inertial force of the drums 23 and 4, which are interconnected by the timing belt 18, acts. Become.

By disconnecting the inertial force of the drive motor 19 in this way, excessive impact force is prevented from being applied to the jamming location, which is extremely advantageous in preventing damage to the tablets and the components of the conveying device 9 At the same time, due to the intervention of the constant torque transmission mechanism 21, the inertial force of the drive motor 19 is separated from the drums 2, 3, 4 when jamming occurs, so that the increase in negative torque due to jamming is immediately applied to the drums 2, 3, 4. This appears as a decrease in the rotational angular velocity of .4. Therefore, the drum rotational angular velocity detection mechanism described below can easily and quickly detect the occurrence of an abnormal load such as a jump, and it is possible to immediately stop the drive motor 19 by braking.

Next, an embodiment of the rotational angular velocity detection mechanism described above will be shown with reference to FIG.

That is, 130 rows of accommodation holes are located outside the tablet conveying path in one of the drums 2, 3, and 4, for example, the first drum 3, and the sensor 270, the light emitting element 28, and the light receiving element 29 are arranged on the outer peripheral surface of the drum. They are installed facing each other on the inner and outer periphery sides of the drum to correspond to the

The housing hole 13 together with the vacuum suction hole 14 constitutes a hole penetrating the drum from the inside to the outside.

Therefore, each element 28 and 29 (ri) of the optical sensor 27 is optically coupled through the aforementioned hole.

With this configuration, the optical sensor 27 functions as a passage detector through which the accommodation hole 13 serves as the detection hole.

An output waveform 30 of the secessor 27 and a pulse signal 31 representing passage through the hole obtained by differentiating the rising portion of each waveform.
The result is as shown in Fig. 6.

As is clear from FIG. 6, when jamming occurs, the speed of the drum decreases compared to the time interval t1 of passing pulses 31 obtained during steady operation, so the time interval of passing pulses 31 changes to t2 (t2>t1). .

In addition, the 13 tablet-accommodating holes are arranged at relatively narrow pitches on the circumference of the drum, so by constantly monitoring the passing pulse signal 31 in Fig. 6, even slight changes in rotational angular velocity can be detected with high sensitivity. Can be detected.

Now, if the time interval of the passing pulse signals obtained by the detection mechanism 2γ becomes shorter than a certain predetermined value, the drum 2,
When a decrease in the rotational angular velocity of the motors 3 and 4, that is, occurrence of a trouble such as jamming, is detected, the drive motor 19 is immediately brought to an emergency stop by an 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 preferably employed.

In addition, at the time of the braking stop described above, the load torque due to jamming, that is, the rotational resistance is very large, and each drum 2, 3
, 4 are stopped immediately, the rotational inertia of each drum does not act as a brake force on the drive motor, and
The connecting pin 25 in FIG. 4 stops at a distance from the right end of the arcuate groove 23.

On the other hand, if the increase in load torque caused by jamming is small and each drum does not stop immediately due to jamming alone, the connection pin 25 and the right end of the arcuate groove 23 are Although they are temporarily separated, they come into contact again, and a portion of the rotational inertia of each drum becomes a braking load on the drive motor 19, and the drive motor is suddenly stopped.

As described above, according to the present invention, the constant torque transmission mechanism 21 described in FIG. 4, the drum rotational angular velocity detection mechanism 27 described in FIGS. The drive motor is configured to brake and stop the drive motor by detecting a change in rotational angular velocity when an abnormal load such as jamming occurs.

Therefore, first, by installing a constant torque transmission mechanism, the inertia of the drive motor is separated from the drum side, so even slight jamming, that is, a relatively small increase in abnormal load torque, can cause a large rotational angular velocity change to the drum. This can be easily detected and the operation can be quickly stopped in an emergency.

Further, by disconnecting the inertia force of the drive motor by the constant torque transmission mechanism, application of an excessive impact load to the jamming location is prevented.

By combining these, it is possible to provide a highly reliable and excellent emergency stop device that can minimize the destruction of solid preparations and failure of the conveyance device during abnormal loads such as jamming, thereby preventing the damage from expanding.

The illustrated embodiment is composed of two drum-shaped conveyance sections,
In addition, although the conveyance device in which the solid preparation is introduced and supplied into the inner space of the supply drum is shown, there is also an outside supply method in which the solid preparation is supplied from the outside of the supply drum, or (ri) which is composed of two drum-shaped conveyance units. The same method can be applied to a two-drum conveying device in which one of the drums also functions as a supply drum.

Further, the drum-shaped conveyance section described here is not limited to only one having a drum structure, but also includes a conveyance section having a similar disk structure or the like.

Furthermore, the present invention includes the above-mentioned appearance inspection device for solid preparations, as well as
For example, it goes without saying that the present invention can also be applied to a conveyance device of a printing press that prints on both sides of a solid preparation.

[Brief explanation of the drawing]

Fig. 1 is an equipment layout diagram of a visual inspection device for solid preparations cited as an example of the implementation target of the present invention, Fig. 2 is a cross-sectional view of the configuration of the conveyance device in Fig. 1, and Fig. 3 is a diagram of the drive mechanism in Fig. 2. , 4th
Figures a and b are side sectional views and front views of the constant torque transmission mechanism according to the embodiment of the present invention, Figure 5 is a configuration diagram of the rotational angular velocity detection mechanism, and Figure 6 shows the output waveform of the detector in Figure 5. FIG. In each figure, common symbols indicate the same or equivalent parts, and the correspondence between the main parts and the symbols is as follows. 2, 3, 4... drum-shaped conveyance section, 10...
...Solid preparation, 11, 13... Accommodation hole for accommodating solid preparation, and accommodation hole, 17, 20...
... Pulley, 18 ... Timing belt, 20
... Drive motor, 21 ... Constant torque transmission mechanism, 22 ... Motor shaft, 23 ...
Arc groove, 24...drive plate, 25...connection pin, 26...screw spring for torque transmission,
27... Optical sensor as a rotational angular velocity detection mechanism.

Claims (1)

[Scope of Claims] 1. A drive motor is connected to a drum-shaped conveying section provided with holes or holes for storing solid preparations arranged at predetermined intervals along the outer circumferential surface, and the drive motor is rotationally driven to transport the solid preparations to the drum-shaped conveying section. In a solid drug transport device that transports a supplied solid drug while holding it in a storage hole or hole, the drum-like transport part is connected and interposed between a drive motor and a drum-shaped transport part, and the transmission torque is maintained during steady operation. A constant torque transmission mechanism that is set to a value corresponding to the required load torque of the transmission torque and 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 rotation of a drum-shaped conveying section. A solid drug delivery device comprising a detection mechanism for detecting angular velocity and a braking means for a drive motor, the drive motor being braked to a stop when the rotational angular velocity of a drum-shaped transport section decelerates below a predetermined value. Emergency stop device in case of abnormal load. 2. The emergency stop device according to claim 1, wherein the constant torque transmission mechanism is directly connected to the shaft of the drive motor, and includes a drive plate having an arcuate groove along the circumferential direction on the plate surface, and one end of which is a driven member. A solid preparation comprising a connecting pin fixed to the arc groove and loosely fitted in the arcuate groove, and a torsion spring for torque transmission stretched across the connecting pin and the drive plate. Emergency stop device in case of abnormal load on transport equipment. 3. In the emergency stop device according to claim 1, the rotational angular velocity detection mechanism detects the rotational angular velocity by monitoring the passing time interval of the solid preparation accommodation hole or hole as the hole to be detected. 1. An emergency stop device for a solid preparation conveying device in the event of an abnormal load, characterized in that the device serves as a passage detector for solid preparation accommodation holes arranged on the outer circumferential surface of a drum-shaped conveyance section or holes arranged opposite to the holes.