The present invention relates to a tablet feeder.
Conventionally, there is a tablet feeder composed of a case support table on which a motor is placed, and a tablet storage case which can be mounted on or dismounted from the case support table. In this kind of the table feeder, when the motor is driven, a rotor disposed inside the tablet storage case is rotated via a plurality of gears so that tablets contained in its pocket can be discharged through a delivery passage.
In this tablet feeder, the tablets discharged from the tablet storage case are counted by a counting sensor provided on the delivery passage. There are a type of the counting sensor which maintains on state regardless of the mounting of the tablet storage case on the case support table, and a type of the counting sensor which is switched to on state only when the tablet storage case is mounted.
However, the counting sensor which constantly maintains on state may suffer erroneous operation due to external perturbations such as light from a fluorescent lamp while the tablet storage case is detached from the case support table. Also, the counting sensor which is switched to on state only when the tablet storage case is mounted on the case support table may suffer errors in the delivery quantity if tablets are accidentally dropped off before the mounting on the tablet storage case is completed and so these tablets are not detectable.
Accordingly, it is a primary object of the present invention to provide a tablet feeder capable of surely preventing erroneous operation from occurring due to the mounting and dismounting of the tablet storage case on and from the case support table.
In the present invention, as a means to solve the above problem, there is provided a tablet feeder in which tablets are delivered from a tablet storage case mounted on a case support table, and when the tablets are passed through a delivery passage formed in the case support table, quantity of the passed tablets is counted by a counting means, comprising:
With this constitution, in the state of the tablet storage case being demounted from the case support table, the counting means can be kept in off state, which makes it possible to restrain unnecessary power consumption and also ensures prevention of the erroneous operation by the counting means due to external perturbations. Further, when the tablet storage case is mounted on the case support table, the counting means is set to on state immediately after the start of mounting. Therefore, even if tablets are accidentally dropped off from the tablet storage case, it becomes possible to reliably count the tablets by the counting means when the tablets are passed through the delivery passage, thereby preventing errors in the delivery quantity from occurring.
The tablet storage case may be provided with an information display section for displaying information about tablets to be stored, and the case support table may be provided with identification means for detecting the information display section, so that the identification means is kept in off state until a start state of mounting of the tablet storage case is detected by the case detection means and is set to on state after detection.
With this constitution, a placement position of the identification means can be determined with disregard to potential adverse influences of external perturbations.
The counting means should preferably be set to on state based on the detection signal from the case detection means after passing of noise influence time, which allows further prevention of detection errors by the counting means.
Embodiments of the invention will now be described with reference to the accompanying drawings.
The tablet feeder 1 is composed of case support tables 3, which are placed on the drawer articles 100 of the tablet feeding apparatus 2A or a drum 102 of the tablet feeding apparatus 2B, and tablet storage cases 4 which can be mounted on or dismounted from the case support tables 3.
As shown in
The tablet storage case 4 is almost in a box shape, and its top surface can be opened and closed with a cover article 13. The upper surface of the bottom wall of the tablet storage case 4 is formed almost into a conical shape, in which a rotor 14 is disposed.
A plurality of groove-shaped pocket sections 15 extending in vertical direction are formed equiangularly on the external surface of the rotor 14. The pocket section 15 has a width and a depth that allows retention of only one tablet that is stored. A rotating shaft of the rotor 14 protrudes from the lower surface of the bottom wall of the tablet storage case 4, and is integrated with a driven gear 16.
Moreover, on the bottom surface of the tablet storage case 4, there are formed guide reception sections 17 which are guided by the guide sections 6 of the case support table 3. On the guide reception sections 17, there is respectively formed an elastic locking reception section 17a which is locked with and unlocked from the locking section 6c formed on each of the guide sections 6a, 6b. A bar code 18 (equivalent to the information display section of this embodiment) detected by the identification sensor 7 is provided on one inner side surface of the guide reception section 17. The bar code 18 corresponds to the kind of a tablet stored in the tablet storage case 4, and information about the tablet such as the kind of the tablet is displayed on an unshown display section based on a detection result of the bar code 18 by the identification sensor 7.
Further, on the other inner side surface of the guide reception section 17, a metal plate 19 is electrically connected to the conductive pattern 8. The metal plate 19 and the conductive pattern 8 constitute the case detection means of the present invention.?
The counting sensor 10 may be set to on state immediately upon contact of the metal plate 19 with the conductive pattern 8, or may be set to on state after passing of estimated time necessary for noise influence due to external perturbations such as light from a fluorescent lamp to disappear at the time of starting mounting of the tablet storage case 4 on the case support table 3. In the latter case, however, if tablets should be dropped off from the tablet storage cases 4 during a period from the start to the end of the mounting of the tablet storage cases 4 on the case support tables 3, it is necessary that the dropped tablets can be detected by the counting sensor 10.
Description is now given of the operation of the above-structured tablet feeder 1.
When the tablet storage case 4 is dismounted from the case support table 3, the metal plate 19 becomes out of contact with the conductive pattern 8, so that the identification sensor 7 and the counting sensor 10 keep on state. This ensures prevention of erroneous detection by the identification sensor 7 or the counting sensor 10 due to external perturbations such as light from a fluorescent lamp.
When the tablet storage case 4 is mounted on the case support table 3, as shown in
Although in the aforementioned embodiment, the case detection means is composed of a combination of the conductive pattern 8 and the metal plate 19 which is simply for obtaining electrical conduction, various means such magnetic sensors including hall elements and MR elements as well as limit switches are also applicable.
Further, in the aforementioned embodiment, the conductive pattern 8 and the metal plate 19 are set to constantly keep a conductive state immediately after the start of mounting of the tablet storage case 4. However, it is also possible to structure so that with partial disconnection of the conductive pattern 8 for example, a state from the start of the mounting of the tablet storage case 4 to the middle of the mounting and a state from the middle of the mounting to the end of the mounting may be separately detected. Consequently, even if the identification sensor 7 as disclosed in the aforementioned embodiment is adopted, it becomes possible to prevent such failure as erroneous detection by the identification sensor 7 when the tablet storage case 4 is not fully mounted on the case support table 3.
Number | Date | Country | Kind |
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2002-4908 | Jan 2002 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP03/00051 | 1/8/2003 | WO |