Medication filling apparatus

Abstract: A medication filling apparatus is equipped with a tablet case (7) for holding medications (5) and a dispensing drum (9) which lets the medications (5) fall through an outlet (7A) from the tablet case (7) as it rotates, thereby dispensing the medications (5), it is further equipped with a plurality of grooves (11) into which the medications (5) from the tablet case (7) are fed and fall therefrom when they are aligned with the outlet (7A) and a separating member (14) which is provided in such a manner that it juts out into or over the groove (11) aligned with the outlet (7A). The separating member (14) is composed of a material which has predetermined lateral and longitudinal dimensions, is flexible and capable of retaining a medication thereon. As the separating member is flexible, it does not scratch the medications that hit it and it also enables medications of different shapes and sizes to be dispensed reliably and smoothly.

Description: BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a medication filling apparatus for filling a container such as a vial or a bag with medications (the medications hereinafter mean tablets, capsules, pills, lozenges, and any other solid medications) in a quantity specified by a prescription at a hospital or the like. Description of the Related Art Conventionally, at a hospital or a pharmacy, medications prescribed by doctors are supplied to patients by using a medication feeding machine as disclosed, for example, in Japanese Examined Utility Model Publication No. 57-7660 (B65D83/04). More specifically, medications in a quantity specified by a prescription are dispensed one by one from a tablet case using a dispensing drum and the dispensed medications are collected by a hopper, a conveyor, etc., then packaged with packaging paper. In this case, the side surface of the dispensing drum in the tablet case is provided with a plurality of vertical grooves, i.e. aligned holes, so that the medications such as tablets, capsules, pills, and lozenges are admitted from the tablet case to the grooves and aligned in a single line in each of the grooves. Under this condition, the dispensing drum is rotated to let the medications fall out of the groove when the groove is aligned with an outlet, i.e. a dropping hole. The medications falling through the outlet are counted by a sensor; when the number of the dropped medications reaches a quantity specified by the prescription, the dispensing drum is stopped, thus filling a container with a predetermined quantity of medications. In a configuration where a groove permits two medications to enter therein vertically, there is a danger that the two medications drop at the same time through the outlet. To prevent this from happening, a conventional apparatus is provided with a separator which juts out in the groove as disclosed in the aforesaid publication so as to allow only one medication to drop at a time. The separator is made of a plate-shaped member such as sheet metal which is thin but resistant to deformation because it is used to separate the medications, e.g. two medications, which have been vertically aligned in the groove provided on the rotating dispensing drum and to let the medications drop one by one. Thus, when the groove is aligned with the outlet, the separator separates the single medication which is in the lowermost position, i.e. the one to drop, from the medication above it so that the lowermost medication is permitted to fall while the medication above it is prevented from falling. The aforementioned tablet case, dispensing drum, etc. are usually composed of synthetic resin primarily to enhance safety, obviate complicated manufacture processes, and protect medications from being scratched. Further, medications include many capsules; therefore, when the dispensing drum is rotated, static electricity is generated from the friction between the rotating dispensing drum and the medications, or among the medications, or between the tablet case and the medications, thus electrifying the medications. As described above, the conventional apparatus employs a hard thin plate-shaped material as the separating plate, presenting a problem in that the separating plate scratches or chips medications. There has been another problem: depending on shape and size of medications, if the medications which have been vertically aligned and fed in the groove are shifted vertically at their contact point, the separating plate would be caught on the side surfaces of the medications, clogging the medications and preventing them from being dispensed. For this reason, a plurality of different types and mounting positions of the separating plates have been conventionally prepared or the mounting position has been made adjustable, so that the separating plate may be changed or adjusted in position to make the separating plate exactly positioned between the vertically aligned medications according to the type of medications placed in the tablet case. Thus, extremely cumbersome work has been required in the conventional apparatus. There has been still another problem: if the medications in the tablet case are electrified, then the medications, which are generally extremely lightweight, stick to the inner surface of the tablet case or the dispensing drum. As a result, the medications do not fall even when the dispensing drum rotates. Moreover, the conventional apparatus is designed so that the aforesaid outlet of the medications is always open and therefore the medications are sometimes over-dispensed due to the inertia force of the dispensing drum. The chance of such over-dispensing increases greatly especially when the rotational speed of the dispensing drum is increased to shorten the filling time. In particular, outside air comes into the table case through the outlet at all times, leading to a problem in that the medications absorb humidity and deteriorate or degrade. There has been another problem in that medications Accidentally drop through the outlet, which is kept open at all times, when the tablet case is detached or attached for filling it with medications or for cleaning it. It is also known from EP-A-0502526 to provide a medication filling apparatus comprising a chamber for a plurality of solid medications and a dispensing drum for dispensing the solid medications from the chamber, the dispensing drum including guide means into which medications are fed from the chamber and separating means for separating the medications fed into the guide means. Medication filling apparatus according to the present invention is characterised in that the separating means is made from a flexible material. With this arrangement, a medication placed on the separating member can be adequately retained; in addition, since the separating member has certain flexibility, the medications will not be scratched even if they bump against the separating member. The problem of the medications being unable to be dispensed due to clogging, which causes an abnormal stop, will be also solved. Even if the type of medications placed in the tablet case is changed and the size and shape of medications accordingly change to cause the separating position of the individual medications in the groove to be shifted and the separating member to be positioned on the side surface of the upper medication, the separating member will resiliently move outward to retain the upper medication in the groove of the dispensing drum since the separating member has certain flexibility and predetermined lateral and longitudinal dimensions. Thus, the medications can be reliably dropped one by one even in such a case as described above; therefore, it is no longer necessary to make fine adjustment of the separating plate according to the size of medications as in the case of the conventional separating plate. Moreover, the versatility is enhanced with a resultant decreased number of different components involved and markedly improved assemblability. In one embodiment, the separating means is a brush. Preferably, an earthed conductive member is located beneath the dispensing drum such that medications in the grooves that are not aligned with the outlet are in contact with the conductive member. This arrangement enables the static electricity to be removed from at least the medications which have been fed into the grooves. Hence, it is possible to prevent the medications from being stuck to the grooves of the dispensing drum, thereby permitting smooth dispensing of the medications. In another embodiment, the separating member is composed of a conductive member that is earthed. This arrangement also enables the static electricity to be removed from at least the medications which have been fed into the grooves. Hence, it is possible to prevent the medications from being stuck to the grooves of the dispensing drum, thereby permitting smooth dispensing of the medications. In another embodiment, the medication filling apparatus is preferably provided with a conductive member on the inner wall of the tablet case and which is grounded. This arrangement enables the static electricity to be removed from the medications placed in the tablet case. Hence, it is possible to prevent the medications from being stuck to the inner wall of the tablet case, thereby permitting smooth dispensing of the medications. Preferably, the medication filling apparatus includes shielding means which normally closes the outlet and opens it only when the dispensing drum is rotated to dispense medications. This arrangement blocks outside air from entering the tablet case through the outlet most of the time, thus solving the problem in that medications absorb humidity and deteriorate or degrade. The arrangement also prevents medications from accidentally dropping out of the outlet when the tablet case is detached or attached for supplying medications or for cleaning. The outlet is closed when the dispensing operation is stopped; therefore, over-dispensing can be securely prevented, enabling accurate filling operation to be achieved. Preferably, driving means normally spaced away from the shielding means is provided, the driving means coming into contact with the shielding means due to centrifugal force generated when the dispensing drum rotates so as to open the outlet. The medication filling apparatus preferably also includes a first spring to bias the shielding means into a closed position in which it is located over the outlet, a centrifugal arm rotatably mounted in the dispensing drum to contact the shielding means and a second spring normally biasing the arm into a position in which it is spaced away from the shielding means, the arrangement being such that rotation of the centrifugal arm against the second spring due to centrifugal force generated in response to rotation of the dispensing drum causes the centrifugal arm to contact the shielding means causing it to turn against the first spring and open the outlet. With this arrangement, the outlet can be opened or closed by the shielding means due to the centrifugal force generated by the rotation of the dispensing means, i.e. the dispensing drum; therefore, it is no longer required to provide a special electric driver for opening and closing the outlet. This permits reduction in production cost and also contributes to energy saving. Moreover, since the shielding means closes the outlet the moment the dispensing means, namely, the dispensing drum, stops, over-dispensing can be prevented even when the rotational speed of the dispensing means, namely, the dispensing drum, is increased. This permits shorter time required for dispensing and filling. Further, the medication filling apparatus in accordance with the present invention preferably includes a shielding plate which is composed of a conductive material and which is grounded, in addition to the arrangement described above. This arrangement removes the static electricity from the medications in the tablet case so as to enable smooth dispensing and charging of medications. Furthermore, the use of the shielding plate to remove the static electricity makes it possible to achieve reduced material cost and improved assemblability. Figure 1 is a front view showing a medication filling apparatus in accordance with the present invention; Figure 2 is a perspective view showing the medication filling apparatus in accordance with the present invention with a top table thereof opened; Figure 3 is a longitudinal side view showing the medication filling apparatus in accordance with the present invention; Figure 4 is a top sectional view showing the medication filling apparatus in accordance with the present invention; Figure 5 is an illustration of the internal configuration of the medication filling apparatus in accordance with the present invention; Figure 6 is a perspective view illustrating a holder unit; Figure 7 is a side view of the holder unit; Figure 8 is a partially cut away perspective view showing the interior of a tablet case equipped with a case grounding plate; Figure 9 is another partially cut away perspective view showing the interior of a tablet case equipped with a case grounding plate; Figure 10 is a longitudinal side view showing the bottom of the tablet case shown in Figure 8; Figure 11 is a front view of a cover; Figure 12 is a sectional view taken on line A-A shown in Figure 11; Figure 13 is a top plan view showing a brush member; Figure 14 is a front view showing the brush member; Figure 15 is a partially cut away perspective view showing the interior of a tablet case of another embodiment, i.e. another dispensing drum, which is equipped with the case grounding plate; Figure 16 is a partially cut away perspective view showing the interior of another tablet case of another embodiment, i.e. another dispensing drum, which is equipped with the case grounding plate; Figure 17 is a longitudinal side view showing the bottom of the tablet case shown in Figure 15; Figure 18 is a block diagram showing a control unit of the medication filling apparatus in accordance with the present invention; Figure 19 is a partially cut away perspective view showing a tablet case of another embodiment; Figure 20 is a longitudinal side view showing the bottom of the tablet case shown in Figure 19; Figure 21 is a top sectional view showing the bottom of the tablet case shown in Figure 19; Figure 22 is a top sectional view showing the bottom of the tablet case shown in Figure 19 for illustrating the operation of a shielding plate; and Figure 23 is a longitudinal side view showing the bottom of the tablet case illustrating still another embodiment. The present invention will be described in more detail in conjunction with the accompanying drawings. A medication filling apparatus 1 according to the present invention is installed at a hospital, pharmacy or the like. A tablet case enclosure 3A is disposed at the top inside a rectangular outer case 3, the tablet case enclosure 3A is open upward and provided with a top table 2 which opens and closes the tablet case enclosure 3A. A filling section 3B, which has an arcuate cross section, is provided on the front surface of the outer case 3. Transparent glass panels (or acrylic panels or the like) 4,4 having arcuate cross sections are installed on both sides on the front surface of the filling section 3B and an inserting opening 6 which is communication with the filling section 3B is provided between the transparent panels 4,4. A plurality of tablet cases 7 are detachably disposed and housed in the tablet case enclosure 3A. The respective tablet cases 7 are filled with different types of medications 5 such as capsules which are shaped like cylinders with predetermined lengths and both ends of which are hemispherical. The inner surface of each of the tablet cases 7 is provided with a case grounding plate 26 which serves as a conductive member and which is disposed vertically on the inner surface. The case grounding plate 26 functions to remove static electricity from the medication 5 or tablet case 7; it is composed of a conductive sheet metal such as copper or stainless steel. A conductive wire 26A is connected in the vicinity of the opening of the tablet case 7; the conductive wire 26A is grounded via a power earth, not shown, so as to remove the static electricity from the tablet case 7 itself or the medication 5 which has been in contact with the case grounding plate 26. Provided beneath the respective tablet cases 7 are corresponding dispensing & counting devices 8. As shown in Fig. 8 through Fig. 10, the dispensing & counting device 8 is comprised primarily of a dispensing drum 9 and a brush member 14 which are provided on the tablet case 7 side and a drum rotating motor 10 for driving the dispensing drum 9 and a photosensor 13 which are provided on the main body, i.e. the outer case 3. The dispensing drum 9 is incorporated at the bottom inside the tablet case 7; the side surface thereof is provided with a plurality of vertical grooves 11 into which the medications 5 such as tablets, capsules, pills, and lozenges are fed vertically in alignment, two pieces in this embodiment. Formed around the side surface, excluding the grooves 11, of the dispensing drum 9 are separating grooves 11A of a predetermined depth which are provided at predetermined distance from the bottom end, the distance being equivalent to the size of one medication 5. The tablet case 7 and the dispensing drum 9 are composed of ABS resin or other hard synthetic resin or the like. The grooves 11 provided on the side surface of the incorporated dispensing drum 9 are formed integrally with the dispensing drum 9. As shown in Fig. 10, the bottom surface of the dispensing drum 9 is provided with a fitting section 9A; a drum grounding plate 27 serving as a conductive member is disposed between the bottom surface of the dispensing drum 9 excluding the portion of the fitting section 9A and the bottom surface of the tablet case 7. The drum grounding plate 27 functions to remove the static electricity at least from the medications 5 which have been fed in the groove 11, the tablet case 7, and the dispensing drum 9; it is also composed of a conductive sheet metal plate of copper, stainless steel, etc. The drum grounding plate 27 is annularly shaped as a whole; the portion corresponds to the outlet 7A has been cut off. The drum grounding plate 27 is mounted under the dispensing drum 9 (in this embodiment, it is provided under the grooves 11 in the moving range of the respective grooves 11 excluding the outlet 7A); it is in contact with a drum grounding plate receiver 27A which is provided on the main body side beneath the tablet case 7 so as to be connected to the power earth which is not shown. A drum rotating motor 10 is provided on the main body side to match the bottom of the dispensing drum 9. A fitting shaft, i.e. a rotary shaft, 10A juts out from the top surface of the drum rotating motor 10; the fitting shaft 10A fits in the fitting section 9A of the dispensing drum 9. When the tablet case 7 is mounted, the fitting section 9A of the dispensing drum 9 fits onto the fitting shaft 10A of the drum rotating motor 10 and the drum grounding plate 27 is brought in contact with the grounding plate receiver 27A. The bottom surface of the tablet case 7 has the outlet 7A which is formed in a position in the rotating range of the grooves 11. A path 12 which is open on a turntable 16, which will be discussed later, is provided on the main body side to match the outlet 7A. As the dispensing drum 9 is driven by the drum rotating motor 10, the medication 5 in the groove 11 which is aligned with the outlet 7A is dropped into the path 12 through the outlet 7A as indicated by a black arrow in Fig. 5. Detachably installed on the side surface of the tablet case 7 above the outlet 7A is a cover 15 as shown in Fig. 11 and Fig. 12; the brush member 14 serving as the separating member composed of a conductive material is attached to the cover. The brush member 14 provides a vertical separator in the groove 11 so as to securely let the medications 5 in the groove drop one at a time through the outlet 7A. As shown in Fig. 13 and Fig. 14, the brush member 14 employs filament fiber 14B composed by a mixture of flexible fiber, i.e. chemical fiber such as nylon, or natural fiber such as animal hair and a conductive material such as carbon. The fiber 14B is implanted at a predetermined density in a fixed plate 14A like a toothbrush having predetermined lateral and longitudinal dimensions. The distal edge of the fiber 14B is trimmed arcuately so that it comes close to or in contact with the bottom surface of the separating grooves 11A of the dispensing drum 9 (see Fig. 13 and Fig. 14). A conductive wire, not shown, is connected to the fiber 14B to ground it via the power earth, thereby removing static electricity from the dispensing drum 9 or the medications 5 in the grooves 11. The cover 15 installs the brush member 14 in a predetermined position on the dispensing drum 9 in a detachable fashion. As shown in Fig. 11 and Fig. 12, a fitting section 15A for fitting a fixing plate 14A of the brush member 14 is formed approximately at the center of the cover 15. Hooks 15B, 15B which engage with the tablet case 7 are provided on both sides of the cover 15; fixing the cover 15 on the tablet case 7 detachably installs the brush member 14 on the side of the dispensing drum 9. In the state described above, the fiber 14B goes into the separating groove 11A to vertically separate the interior of the groove 11; it positions itself between the lowermost medication 5 and the medication 5 thereover which have been fed into the groove 11 in alignment. The photosensor 13 is installed in a position for detecting the medications 5 which fall out through the outlet 7A. The turntable 16 is provided in the main body, i.e. the outer case 3, under the tablet case 7 and the dispensing & counting device 8; the turntable 16 is shaped like a disc and has a sufficiently large area to match the bottom area of all the tablet cases 7 and the dispensing & counting devices 8. The turntable 16 has a projection cone 16A at the center thereof; there are also provided separating vanes 17, 17 which extend in the radial direction from the projecting cone 16A (Fig. 5). A turntable motor 18 provided beneath the projecting cone 16A drives and rotates the turntable 16 in the direction of the arrows shown in the drawing at a predetermined speed. An annular guide 21 is provided vertically around the turntable 16; a notch-shaped dispensing port 22 is formed at the front end of the guide 21. The dispensing port 22 communicates the turntable 16 with the area outside the guide 21. The dispensing port 22 is opened and closed by a shutter 23 which swings outward. The shutter 23 is driven by a shutter activating means 24 of a solenoid plunger or the like, which will be discussed later. The vertical dimension of the turntable 16 including the guide 21 is approximately 10 cm. Provided at the bottom front of the turntable 16 and the guide 21 is a holder unit 31 which temporarily retains the medications 5. As shown in Fig. 6 and Fig. 7, the holder unit 31 is equipped with a disc base 32 at the top and a plurality of holders 33 (12 holders in this embodiment) which jut out from the base 32 downward and outward aslant (at 60 degrees in the embodiment). The top ends of the respective holders 33 are open through inlets 33A provided in the base 32, while the bottom ends thereof are open through an outlets 33B. Further, the respective holders 33 extend radially from the center of the base 32; the respective inlets 33A and the respective outlets 33B are arranged on virtual circles which are concentric with the base 32. The respective holders 33 are equipped with covers 36 for opening and closing the respective outlets 33B although only one cover is shown in Fig. 5 and Fig. 6; the covers 36 close the outlets 33B at all times by springs or the like which are not shown. Each cover 36 has a handle 37 sticking out of the holder 33 and the cover 36 is swung by the handle 37 to open the outlet 33B. A rotary shaft 38 juts out downward from the center of the base 32 of the holder unit 31. A holder motor 39 is attached to the rotary shaft 38 and the holder unit 31 is driven and rotated by the holder motor 39. The holder unit 31 is equipped with a holder position sensor 41 for detecting the positions of the respective holders 33, which will be discussed hereinafter. Inside the filling section 3B of the aforesaid outer case 3, there is provided a bar code reader 42 which is located near the inserting opening 6. Provided on the top surface of the filling section 3B are a key switch 43 consisting of ten keys and a display 47 for showing prescription data and preparing state and for giving an alarm. Figure 18 is the block diagram showing a control unit 44 of the medication filling apparatus 1 which comprises a general-purpose microprocessor 45. As the dispensing drum 9 rotates, the tablet cases 7, the dispensing drum 9, the medications 5, etc. are charged with static electricity. The static electricity, however, is removed from the medications 5 since the medications 5 come in contact with the case grounding plate 26 at the top of the tablet case 7, or the bottom ends of the medications 5 come in contact with the drum grounding plate 27 when they are in the grooves 11 in the rotating range thereof. As the dispensing drum 9 rotates, the medications 5 fall from the groove 11 which is aligned with the outlet 7A; at this time, the brush member 14 is placed between the two medications 5,5 vertically aligned in the groove, so that the brush member 14, which is in contact with the groove 11 and the medications 5, removes the static electricity therefrom while retaining the upper medication 5 at the same time. This allows only the lower medication 5 under the brush member 14 to drop from the groove 11 without sticking to the groove 11 due to static electricity. The medications 5 do not stick to the upper inner surface of the tablet case 7, either. Thus, the medications 5 smoothly drop from the respective grooves 11 one by one as the dispensing drum 9 rotates. The arrangement described above also solves the problem with the conventional apparatus in that the generated static electricity causes the medications 5 to stick to the grooves 11 of the dispensing drum 9, preventing the medications 5 from being dispensed. Since the brush member 14 is composed of the flexible filament fiber 14B which is implanted in the fixed plate 14A at the predetermined density in the form of a toothbrush having predetermined lateral and longitudinal dimensions, it is capable of securely holding the medication 5 thereon. In addition, since the brush member 14 has certain flexibility in the radial direction, i.e. outward, of the dispensing drum 9 and also in the vertical direction, even if the medications 5 bump against the brush member 14, the medications 5 will not be scratched and the medications will not be caught, either, thus preventing a dispensing failure which causes an abnormal stop. When a different type of medications 5 are put in the tablet case 7 and the separating position of the medications, namely, the contact point between the two medications 5,5 in the groove 11, is shifted because of the different size and/or shape of the medications 5 such as in a case where shorter capsules are charged in the tablet case 7, the brush member 14 will be positioned at the side surface of the upper medication 5; as previously described, the brush member 14 exhibits certain flexibility in the radial direction of the dispensing drum 9 and has the predetermined lateral and vertical dimensions, therefore, the fiber 14B of the brush member 14 resiliently moves outward, i.e. toward the tablet case 7 and it also securely retains the upper medication 5 between itself and the bottom surface of the groove 11 of the dispensing drum 9. Accordingly, even in such a case, the medications 5 can be securely dropped one at a time and it is no longer necessary to make fine adjustment of the separating plate according to the size of the medications 5 as in the conventional apparatus. In addition, the enhanced versatility permits a reduced number of different components used and also enables improved assemblability. Thus, the medications drop one by one as previously mentioned and the dropped medications are received by the turntable 16. The medications 5 that have dropped are counted by the microprocessor 45 according to the output received from the photosensor 13. The microprocessor determines whether the counting has been completed; if the determination result is negative, then the same process is repeated. When the number of dropped medications 5 detected by the photosensor 13 coincides with the number of the medications 5 based on the prescription data, the microprocessor 45 decides that the counting has been completed and it stops supplying electric current to the drum rotating motor 10. The medication 5 which has dropped onto the turntable 16 moves toward the guide 21 located on the circumference of the turntable 16 due to the centrifugal force of the rotating turntable 16. At this time, since the projecting cone 16A is located at the center of the turntable 16 at which the centrifugal force is weaker, the medication 5 dropped onto the center moves outward along the slope of the projecting cone 16A and then moves toward the guide 21 owing to the centrifugal force. The separating vanes 17,17 provided on the turntable 16 turn with the turntable, so that the medication 5 which stays stationary on the turntable 16 is also pushed and moved outward smoothly. Thus, the medications 5 dropped onto the turntable 16 are collected and moved to the guide 21 and aligned, being pushed against the guide 21. Next, the microprocessor 45 positions on empty holder 33 under the dispensing port 22 of the guide 21 with the aid of the holder position detecting sensor 41 and then swings the shutter 23 outward as shown in Figure 5 by the shutter activating means 24 to open the dispensing port 22 for a predetermined time (e.g. 1 second) and then close it. When the dispensing port 22 is opened, the medications 5 aligned against the inner circumferential wall of the guide 21 are collected at the dispensing port 22 one after another by the centrifugal force and moved into the holder 33 through the inlet 33A of the holder 33. The microprocessor 45 repeats the procedure for all types of medications 5 specified by the prescription data to fill the separate holders 33 for the different types of medications. Thus, according to the present invention, as the separating member for separating the medications 5,5 in the groove 11, the brush member 14 is employed which is composed of the flexible filament fibers 14B implanted in the fixed plate 14A at the predetermined density in the form of a toothbrush having predetermined lateral and longitudinal dimensions; therefore, the medication 5 placed on the brush member 14 can be securely retained. Moreover, since the brush member 14 has certain flexibility in the radial direction, i.e. outward, of the dispensing drum 9 and also in the vertical direction, even if the medications 5 bump against the brush member 14, the medications 5 will not be scratched and the medications 5 will not be caught, either, thus preventing a dispensing failure which causes an abnormal stop. Even when the type of medications is changed and the size and shape of medications accordingly change, the fiber 14B of the brush member 14 will resiliently move outward to retain the upper medication 5 between itself and the bottom surface of the groove 11 of the dispensing drum 9. Accordingly, the medications 5 can be reliably dropped one by one in such a case as described above; in addition, it is no longer necessary to make fine adjustment of the mounting position of the separating plate according to the size of medications 5 as in the case of the conventional separating plate. Moreover, the versatility is enhanced with a resultant markedly improved assemblability and a decreased number of different components involved. The case grounding plate 26 is provided on the inner side surface of the tablet case 7 and the drum grounding plate 27 is installed between the bottom surface of the dispensing drum 9 and the tablet case 7; therefore, even if static electricity is generated as the dispensing drum 9 runs and the tablet case 7, the dispensing drum 9, and the medications 5 are electrified, the static electricity can be removed through the case grounding plate 26 and the drum grounding plate 27 via the conductive wire 26A and the drum grounding plate receiver 27A. Hence, the charges on the dispensing drum 9 or the medications 5 can be removed before they generate an abnormally high potential. This allows the medications 5 in the groove to fall smoothly, thus preventing the medications 5 from being stuck in the groove 11 and failing to fall. Furthermore, since the conductive brush member 14 is attached to the side surface of the dispensing drum 9, even if static electricity remains on the medications 5, the remaining static electricity is further removed by the brush member 14, thus further enhancing the prevention of the medications 5 from being stuck in the groove 11 and failing to drop. Referring now to Figure 15 through Figure 17, an embodiment which employs a dispensing drum 29 having a different shape will be described. In this embodiment, the tablet case 7 holds medications 5A which are elliptical tablets having a predetermined thickness. In these drawings, like reference numerals given in Figure 1 through Figure 14 designate like components or components providing like functions. The dispensing drum 29 is driven by the drum rotating motor 10 as in the first embodiment and the control is carried out in the same manner as in the first embodiment. The dispensing drum 29 of the dispensing and counting device dispensing and counting device 8 in this embodiment has a smaller vertical dimension; it is provided with a plurality of vertical grooves 30 on the side surface thereof. Medications 5A such as pills, lozenges, and other types of tablets are fed into the groove 5A one at a time. The brush member 14 juts out from side to cover the top of the grooves 30 of the dispensing drum 29. The brush member (separating member) 14 which is the conductive member and which is provided on the side surface of the dispensing drum 29 is positioned over the groove 30 of the dispensing drum 29; it prevents more than one medications 5A from entering the groove 30. Thus, the brush member 14 permits only one medication 5A to drop at a time from the groove 30. The brush member 14 is grounded with the conductive wire which is not shown. The tablet case 7 is provided with the case grounding plate 26, which is conductive, as in the first embodiment, so that it is grounded via the connected conductive wire 26A. Provided under the dispensing drum 29 is the drum grounding plate 27 serving as the conductive member. Other operations are available as in the first embodiment. A still another embodiment of the medication filling apparatus 1 in accordance with the present invention will now be described in conjunction with Figure 19 through Figure 23. In these drawings, like reference numerals given in Figure 1 through 18 designate like components or components providing like functions. The dispensing drum 9 and other component units are controlled in the similar manner as described in the embodiments described above. The dispensing drum 9, i.e. the dispensing means, of the dispensing and counting device 8 is a hollow cylinder opened downward; there is provided a fitting section which extends downward from the top end of the inner center of the dispensing drum 9 and which is not shown; and the drum rotating motor 10 is provided under the dispensing drum 9. The fitting shaft, i.e. the rotary shaft, which is similar to that in the embodiments described above and which is not shown, juts out from the top surface of the drum rotating motor 10; the fitting shaft 10A fits in the fitting section of the dispensing drum 9. When the tablet case 7 is mounted, the fitting section of the dispensing drum 9 fits onto the fitting shaft of the drum rotating motor 10. A shielding plate 51 serving as a shielding means is provided on the bottom surface of the tablet case 7. The shielding plate 51 is constituted by: a nearly annular base 52; a shielding section 53 which projects outward from a part of the outer circumference of the base 52; a friction wall 54 which extends from the top surface of the base 52 into the dispensing drum 9 above and which has an arcuate cross section (only one is shown in this embodiment; however, providing a plurality of the friction wall will add to reliability); and an arcuate slot 56 formed on the base 52. The shielding plate 51 is rotatably disposed at the bottom of the dispensing drum 9 in such a manner that it is concentric with the dispensing drum 9. The shielding section 53 has an adequate area for covering the outlet 7A; it is located over the outlet 7A. The fitting section of the dispensing drum 9 or the fitting shaft of the drum rotating motor 10 passes through the center of the base 52. A pin 57 extends from the bottom surface of the tablet case 7; it engages in the slot 56 of the base 52 of the shielding plate 51. This allows the shielding plate 51 to turn within the slot 56. A first spring (tension spring) 58 is installed between the pin 57 and the end of the slot 56 on the shielding section 53 side. The urging force of the spring 58 holds the shielding plate 51 in place so that the outlet 7A is closed by the shielding section 53 at all times (Figure 19). When the shielding plate 51 is turned in the direction of the arrow in Figure 19 against the urging force, i.e. the pulling force, applied by the spring 58, the shielding section 53 opens the outlet 7A. Installed in the dispensing drum 9 is a centrifugal arm 61 serving as a driving means. The centrifugal arm 61 has an arcuate external shape which matches the inner wall shape of the friction wall 54; it is rotatably mounted to one edge of the inner wall of the dispensing drum 9 at a rotary shaft 62 which is attached to one end of the centrifugal arm 61. Thus, the centrifugal arm 61 is located inside the friction wall 54 (Figure 20 shows the dispensing drum 9 which has turned 90 degrees from the state illustrated in Figure 19). A weight 63 is attached to the other end of the centrifugal arm 61; a second spring 64, which is a compression spring, is installed between the weight 63 and the inner surface of the side wall of the dispensing drum 9. The spring 64 always urges or stretches the centrifugal arm 61 so that it stays away from the friction wall 54 with a gap "a" between them; if the spring 64 is compressed against the urging force, then the outer surface of the centrifugal arm 61 comes in contact with the inner surface of the friction wall 54 with a predetermined frictional force. An annular conductive plate 66 with the portion of the outlet 7A cut out is mounted on the bottom surface of the tablet case 7 in the rotating range of the grooves 11. The conductive plate 66 is located under the shielding plate 51; the lowermost one among the medications 5 which have been fed into the groove 11 comes in contact with the conductive plate 66 which is grounded through the contact with a conductive plate 68 fixed to the outer case 3 via a conducting plate 67 when the tablet case 7 is installed. The operation of the embodiment with the configuration described above will now be described. When the power is ON, the dispensing drum 9 is in a stopped state, the centrifugal arm 61 is spaced away from the friction wall 54 by the spring 64, the shielding plate 51 is pulled by the spring 58, and the shielding section 53 closes the outlet 7A. Hence, normally, the outside air does not enter into the tablet case 7 through the outlet 7A, preventing the medications 5 from absorbing humidity and deteriorating or degrading. Furthermore, even when the tablet case 7 is detached and attached back again for supplying the medications 5 or for cleaning the tablet case 7, medications 5 do not accidentally drop out of the outlet 7A. Based on prescription data, the drum rotating motor 10 of the dispensing and counting device dispensing and counting device 8 of the tablet case 7 holding the type of medications 5 specified in the prescription data is driven as previously described. When the dispensing drum 9 is rotated in the direction of the arrow shown in Figure 19, the centrifugal arm 61 rotates together with the dispensing drum 9; at this time, the centrifugal arm 61 turns around the rotary shaft 62 against the urging force of the spring 64 due to the centrifugal force so that the weight 63 on the other end moves outward. This causes the outer surface of the centrifugal arm 61 to come in contact with and pressed against the inner surface of the friction wall 54; therefore, the frictional force at this time causes the shielding plate 51 to turn also in the rotational direction of the dispensing drum 9 against the urging force of the spring 58. This in turn causes the shielding section 53 of the shielding plate 51 to open the outlet 7A as previously described (Figure 22). Then, the medication 5 drops from the groove 11 which is aligned with the opened outlet 7A. The dimensions of the centrifugal arm 61 are set so that a portion thereof comes in contact with the friction wall 54 to open the outlet 7A during the rotation of the dispensing drum 9. When the number of dropped medications 5 coincides with the number of the medications based on the prescription data, the microprocessor 45 decides that the counting has been completed and it stops supplying electric currents to the drum rotating motor 10. Stopping the supply of electric currents to the drum rotating motor 10 stops the dispensing drum 9; as the revolution of the dispensing drum 9 changes, that is, slows down, and the centrifugal force on the centrifugal arm 61weakens, the centrifugal arm 61 is immediately pushed inward by the spring 64, leaving the friction wall 54. This causes the shielding plate 51 to be pulled back by the spring 58 and the outlet 7A is closed by the shielding section 53. Hence, even when the dispensing drum 9 continues to rotate owing to inertia force, although it is actually an extremely short time, after the supply of electric currents to the drum rotating motor 10 is stopped, the medications 5 are prevented from being dispensed from the groove 11, thus assuring the prevention of over-dispensing. Therefore, the rotational speed of the dispensing drum 9 can be increased to shorten the time required for dispensing without the problem of over-dispensing. Moreover, although the medications 5 in the tablet case 7 are charged with static electricity owing to the rotation of the dispensing drum 9 or other reason, the medications 5 fed in the groove 11 come in contact with the conductive plate 66 whenever they reach the lowest level in the groove, so that the static electricity is discharged from the medications 5 to the outer case 3 via the conductive plate 66, and the conducting plates 67 and 68. Thus, the static electricity is removed from the medications 5, preventing a dispensing failure from taking place due to the medications 5 being stuck to the tablet case 7 or dispensing drum 9. Figure 23 shows yet another embodiment of the tablet case 7 and dispensing & counting device 8 in accordance with the present invention which correspond to the one shown in Figure 20. In this embodiment, the shielding plate 51 does not have the shielding section 53; instead, the width of the base 52 has been increased and the whole outer section thereof is located under the full area where the grooves 11 of the dispensing drum 9 rotate. The base 52 is also provided with a through hole or notch, not shown; the base 52 normally closes the outlet 7A, but when it rotates as the dispensing drum 9 is rotated and the through hole or notch is aligned with the outlet 7A, it opens the outlet 7A. The shielding plate 51 in this embodiment is composed of a conductive material such as a metal plate, and a conductive plate 71 is in contact with the bottom surface thereof. The conductive plate 71 is grounded via the conducting plates 67 and 68 as in the aforementioned embodiments. According to this embodiment, the shielding plate 51 also provides the function of the conductive plate 66 in the aforementioned embodiments, and the conductive plate 71 can be made smaller, enabling better assemblability and reduced material cost. In the embodiments described above, the brush member 14 is used as the separating member. The separating member, however, is not limited to the brush member; it may be an elastic member such as a sponge member which exhibits the similar function. Likewise, in the embodiments described above, only one case grounding plate 26 is installed in the tablet case 7; however, two or more case grounding plates 26 may be provided in the tablet case 7. As another alternative, the case grounding plate may be provided in the whole interior of the tablet case 7. The metal plate such as a stainless steel plate is employed for the case grounding plate 26 in the embodiments; however, cloth or the like made of conductive fiber with carbon or the like mixed therein may be used instead. Further, although the vials are used as the containers in the respective embodiments, the type of container to be used is not limited thereto; the present invention can be also effectively implemented also when packaging paper which is formed into a bag is used as the container. Thus, the medication filling apparatus in accordance with the present invention is useful for filling a container such as a vial or bag with medications including tablets, capsules, pills and lozenges in a quantity specified by a prescription at a hospital, pharmacy, or the like; it is particularly suited for charging many different types of medications.

Claims: Medication filling apparatus comprising a chamber (7) for a plurality of solid medications (5) and a dispensing drum (9) for dispensing the solid medications (5) from the chamber (7), the dispensing drum (9) including guide means (11) into which medications (5) are fed from the chamber (7) and separating means (14) for separating the medications (5) fed into the guide means (11) characterised in that the separating means (14) is made from a flexible material. A medication filling apparatus according to claim 1, wherein the chamber includes an outlet and the guide means comprises a plurality of grooves (11) which are formed vertically on a side surface of the dispensing drum (9), the arrangement being such that the medications (5) drop from the grooves (11) through the outlet when the grooves (11) are aligned therewith. A medication filling apparatus according to claim 2, wherein the separating member extends across the groove aligned with the outlet to separate the medications disposed therein, thereby permitting only one medication to drop from a groove (11) disposed over the outlet (7A). A medication filling apparatus according to any preceding claim, wherein the separating means is a brush (14). A medication filling apparatus according to any of claims 1 to 4, wherein an earthed conductive member (27) is located beneath the dispensing drum (9) such that medications in the grooves (11) that are not aligned with the outlet (7A) are in contact with the conductive member (27). A medication filling apparatus according to any of claims 1 to 4, wherein the separating member is composed of a conductive member (27) that is earthed. A medication filling apparatus according to any of claims 1 to 6, wherein a conductive member (26) is provided on the inner wall of the chamber (7), the conductive member (26) being earthed. A medication filling apparatus according to any preceding claim, wherein shielding means (51) closes the outlet (7A) and is moveable to open the outlet (7A) when medications are to be dispensed. A medication filling apparatus according to claim 8, wherein driving means (61) normally spaced away from the shielding means (51) is provided, the driving means (61) coming into contact with the shielding means (51) due to centrifugal force generated when the dispensing drum (9) rotates so as to open the outlet (7A). A medication filling apparatus according to claim 9 comprising a first spring (58) to bias the shielding means (51) into a closed position in which it is located over the outlet (7A), a centrifugal arm (61) rotatably mounted in the dispensing drum (9) to contact the shielding means (51) and a second spring (64) normally biasing the arm (61) into a position in which it is spaced away from the shielding means (51), the arrangement being such that rotation of the centrifugal arm (61) against the second spring (64) due to centrifugal force generated in response to rotation of the dispensing drum (9) causes the centrifugal arm to contact the shielding means (51) causing it to turn against the first spring (58) and open the outlet (7A). A medication filling apparatus according to any of claims 8 to 10 wherein the shielding means (51) is composed of a conductive material and is earthed.

Inventors: ITO KENICHI, NIIJIMA TOSHIYUKI, ITO, KENICHI, NIIJIMA, TOSHIYUKI
Applicants: SANYO ELECTRIC CO, SANYO ELECTRIC CO., LTD.
Application year: 1996
Main classification: A61J7
IPC codes: B65B1, A61J3, A61J7