TECHNICAL FIELD
[0001] The present invention relates to a tablet cassette that forms a driven portion in
a tablet feeder configured to automate dispensing of medicines in hospitals, pharmacies,
etc. Particularly, the present invention relates to a tablet cassette for a tablet
feeder, including a tablet container configured to contain tablets and a rotor located
in the tablet container, wherein the tablet cassette causes the tablets to consecutively
fall through a discharge port of the tablet container while aligning the tablets around
the rotor when the rotor is driven to axially rotate. More particularly, the present
invention relates to the structure of a rotary member (a fall prevention portion,
/a partitioning portion) configured to limit only the lowermost one of the tablets
above the discharge port as the tablet that is to fall down.
BACKGROUND ART
[0002] Tablet feeders that have conventionally been used (see Patent Documents 1 to 4:
JP H02-205523 A,
JP 2002-153541 A,
JP 2002-154637 A, and
JP 2012-120719 A) include a base (a drive portion) fixed to a drawing shelf or the like of a tablet
dispensing apparatus for power supply and control, and a tablet cassette removably
attached to the base to facilitate tablet replenishment or the like. A large number
of tablets are contained in the tablet cassette in a random manner, and the base is
caused to intermittently or continuously operate, as necessary, to feed the tablets,
one at a time. In some of tablet splitting apparatuses of an independent type (see
Patent Document 5:
JP 2012-179127 A, for example), the tablet cassette discussed above is removably attached on top of
a body portion that includes a cassette drive portion in addition to a tablet cutting
mechanism.
[0003] Such a tablet cassette for a tablet feeder includes a tablet container, a rotor and
a partition plate. The tablet container is configured to contain a large number of
tablets, which have been supplied with an upper lid of the container being opened,
in the internal space of the tablet container. The rotor is axially rotatably provided
in the tablet container and includes a rotation transmission shaft configured to receive
drive of a drive portion. The tablet container includes a bottom wall portion defining
a lower end portion of an annular gap formed between the tablet container and the
rotor. The bottom wall portion has a discharge port formed therein so as to penetrate
the bottom wall portion. The partition plate is provided to face the discharge port
and configured to partition a part of the annular gap on the upper end side. A through
hole shaped in a slit that allows insertion of the partition plate is formed in a
peripheral wall portion of the tablet container at a position above partition walls
and upward from the discharge port, in order to allow the partition plate to be mounted
from the outside of the tablet container.
[0004] The annular gap, in which the tablets are to be aligned, is partitioned by a plurality
of partition walls into spaces to receive the tablets on one-for-one basis. The plurality
of partition walls are each shaped in a blade and are formed at an equal pitch on
an outer peripheral portion of the rotor to project into the annular gap. Spaces between
adjacent partition walls serve as tablet receiving portions configured to each receive
one tablet which has fallen from above the rotor.
[0005] When the tablet cassette for a tablet feeder is mounted to a base or the like (a
drive portion), the rotation transmission shaft of the rotor is engaged with a rotational
drive shaft of the drive portion and is rotationally driven.
[0006] When a tablet is carried in the annular gap by the rotor that is rotating to a location
directly above the discharge port, the tablet falls to be discharged through the discharge
port, and tablets above the falling tablet are prevented from entering the discharge
port by the partition plate. This prevents fall of two tablets at a time, and the
tablets are discharged according to the amount of rotation, one at a time.
[0007] While the tablet container and the rotor are made from a hard plastic material, the
partition plate for tablet fall prevention is made from metal or a soft material.
The partition plate which is made from metal (see Patent Document 1:
JP H02-205523 A, for example) is formed by bending a thin metal plate or the like, and includes a
vertical plate portion for attachment from the outside of the tablet container, and
a horizontal plate portion extending into the internal space of the tablet container
to exhibit the partitioning function. Meanwhile, the partition plate which is made
from a soft material (see Patent Documents 2 and 3:
JP 2002-153541 A and
JP 2002-154637 A, for example) is formed by plastic molding or the like. Such a partition plate is
shaped in a flat plate to be soft and easily deformable so as not to damage the tablets.
A partition plate with a saw-tooth shaped portion that exhibits the partitioning function
is especially soft. Further, some partition plates are of a so-called cantilever type
in which only one end portion of the partition plate is attached to the tablet container
(see Patent Document 1:
JP H02-205523 A, for example), while other partition plates are of a so-called double support type
in which both end portions of the partition plate are attached to the tablet container
(see Patent Documents 2 and 3, for example). The attachment of the partition plates
is different, direct attachment (see Patent Document 1, for example) and indirect
attachment in which the partition plate is attached via a support or the like (see
Patent Documents 2 and 3, for example).
[0008] Such tablet cassettes for a tablet feeder handle tablets, not powdered medicine.
While tablets shaped in a circular plate are typical, the tablet cassettes for a tablet
feeder often handle tablets shaped in regular polygon, cylindrical capsules, etc.
[0009] The tablet cassettes for a tablet feeder occasionally handle oddly shaped tablets
having a shape of a diamond plate shape, a spindle with a swelled middle portion,
halved tablets prepared by cutting one tablet in half to allow dosing of less than
one tablet at a time, rather than so-called regular shaped tablets such as those of
a circular shape, a spherical shape, a regular polygonal shape, and a regular polyhedron
shape.
[0010] In order for the conventional tablet cassettes for a tablet feeder discussed earlier
to handle the oddly shaped tablets or the halved tablets discussed above, careful
adjustment or troublesome preparation that is not necessary for the regular shaped
tablets is required. Therefore, a tablet cassette for a tablet feeder that can handle
even the oddly shaped tablets and the halved tablets as easily as the regular shaped
tablets has been developed and well-received.
[0011] Such tablet cassettes for a tablet feeder will be discussed in detail (see Patent
Documents 1 to 5). If the tablet cassette for a tablet feeder that uses a partition
plate handles the regular shaped tablets, and when one tablet is received in a tablet
receiving portion between partition walls in an annular gap formed between the tablet
container and the rotor and another tablet comes over the tablet that is already received
in the tablet receiving portion, the tablet overlies the one tablet in the tablet
receiving portion or the partition walls, and even a part of the overlying tablet
cannot be received in the tablet receiving portion. Thus, the tablets can reliably
fall consecutively and be consecutively discharged since the tablets are vertically
separated from each other appropriately in this situation naturally and appropriately,
even if the positional adjustment of the partition plate is more or less imprecise.
Thus, the partition plate can be relatively adjusted with ease.
[0012] In contrast, for the oddly shaped tablets with a narrow or pointed end portion and
the halved tablets, a relatively large space tends to be left unoccupied at the lower
portion or the upper portion of a tablet receiving portion of the annular gap when
such oddly shaped tablet is received in the tablet receiving portion. Therefore, when
another tablet subsequently comes over the tablet receiving portion in which the preceding
tablet is already received, the lower end portion of the subsequently coming tablet
occasionally enters the upper space in the tablet receiving portion, depending on
the posture of the upper tablet. In such a case, however, the partition plate does
not have any position at which the partition plate can vertically separate the tablets
from each other, or if any, such position as allows for vertical separation of the
tablets is limited to a narrow range. Therefore, it is necessary to find an appropriate
position of the partition plate by trial and error through an experiment or the like,
and even if such a position is found, the position of the partition plate must be
exactly adjusted. In addition, in order for a tablet, a part of which has entered
a tablet receiving portion, to move upward completely out of the tablet receiving
portion such that the entire tablet moves to a location above the partition plate
when the tablet abuts on the partition plate, it is important to have end portions
of the oddly shaped tablets and cut surfaces of the halved tablets smoothed. Thus,
it is occasionally necessary to make preparations such as screening the tablets in
advance, neatly cutting the tablets, and finishing the surfaces.
[0013] Since the oddly shaped tablets and the halved tablets are more difficult to handle
than the regular shaped tablets as described above, frequently the oddly shaped tablets
and the halved tablets are not handled by a fully automatic tablet cassette for a
tablet feeder, and are often handled by a semi-automatic medicine hand-dispensing
device or manually. While the oddly shaped tablets are increasing along with an increase
in the number of types of medicines, prescription of the halved tablets also tends
to increase from the viewpoint of finely adjusting the number of tablets as dosage
according to the weight or the like of each patient, for example, in order to suppress
a side effect. Along with such tendency, there has been an increasing demand to automate
medicine dispensation and improve efficiency. Thus, a tablet cassette for a tablet
feeder, which can handle the oddly shaped tablets and the halved tablets as easily
as the regular shaped tablets, has been developed in order to meet such a demand.
[0014] Specifically (see Patent Document 6:
JP 2015-012893 A), the fall prevention member that prevents fall of two tablets at a time has been
changed from the partition plate discussed above to an endless belt of a flat string
shape or a round string shape.
[0015] Moreover, the endless belt that is newly adopted in place of the partition plate
is formed from an elastic member or a flexible member that is easily deformable, and
is provided at a position above the partition walls and upward from the discharge
port. When one of the tablet receiving portions comes closer to the discharge port
due to axial rotation of the rotor, a tablet that protrudes out of the tablet receiving
portion abuts on the endless belt, and the endless belt exerts its repulsive force
to push the tablet from the outer peripheral side toward the inner peripheral side,
thereby preventing the tablet from falling into the discharge port.
[0016] Such a tablet cassette for a tablet feeder that adopts the endless belt as the fall
prevention member has demonstrated improved compatibility with not only the regular
shaped tablets but also the oddly shaped tablets and the halved tablets by means of
partial modifications while following the proven basic structure according to the
related art as a whole. That is, when one of the plurality of tablet receiving portions
comes closer to the discharge port due to axial rotation of the rotor, the fall prevention
member located above the discharge port abuts on a tablet that protrudes out of the
tablet receiving portion from the outer peripheral side to push the tablet toward
the inner peripheral side, and only a tablet in the tablet receiving portion falls
through the discharge port, thereby preventing fall of the overlying tablet that protrudes
out of the tablet receiving portion. In that event, the protruding main part of the
tablet that protrudes out of the tablet receiving portion is pushed toward the inner
peripheral side, even if a part of the tablet has entered the tablet receiving portion,
and the entire tablet is held between the rotor and the fall prevention member, or
the main part of the tablet is gently pushed up to a location above the rotor so that
the remaining part of the tablet in the tablet receiving portion also gets out of
the tablet receiving portion accordingly. Thus, there is no concern that a part of
the tablet that has entered the tablet receiving portion and the main part of the
tablet that protrudes out of the tablet receiving portion are separated from each
other. Therefore, even if the tablets are the oddly shaped tablets or the halved tablets,
there is no need to make careful adjustment or troublesome preparation, and it is
only necessary to make adjustment and preparation that are the same as or similar
to those for the regular shaped tablets.
Related-Art Documents
Patent Documents
SUMMARY OF INVENTION
TECHNICAL PROBLEM
[0018] As described above, the tablet cassette for a tablet feeder which adopts the endless
belt is easy to use with not only the regular shaped tablets but also non-regular
shaped tablets.
[0019] In the tablet cassette for a tablet feeder that adopts the endless belt, however,
the endless belt must be supported at two or more locations for tension of the belt,
and it is necessary to incorporate axial rotation members at support portions for
smooth circulation of the endless belt.
[0020] Therefore, the tablet cassette for a tablet feeder that adopts the endless belt requires
a large number of members for the support portions for the fall prevention member
compared to the tablet cassette for a tablet feeder that adopts the partition plate
of the double support type, not to mention the tablet cassette for a tablet feeder
that adopts the partition plate of the cantilever type. In addition, it is difficult
to reduce the cost of the tablet cassette for a tablet feeder that adopts the endless
belt.
[0021] Thus, it is a technical issue to provide a tablet cassette for a tablet feeder that
requires only a small number of support members while taking over the properties of
a fall prevention member of an endless belt type, that is, to prevent fall of two
tablets at a time, by gently pushing a tablet from the outer peripheral side toward
the inner peripheral side over a discharge port.
SOLUTION TO PROBLEM
[0022] The tablet cassette for a tablet feeder according to the present invention has been
devised to address the foregoing issue. The tablet cassette for a tablet feeder includes:
a tablet container configured to contain a large number of tablets, and including
a bottom wall portion having a discharge port formed therein, and a peripheral wall
portion; a rotor having a rotary shaft that rotatably penetrates the bottom wall portion
of the tablet container and being rotatable about the rotary shaft, the rotor having
an upper surface shaped to align a plurality of tablets; and a plurality of partition
walls extending radially from an outer peripheral portion of the rotor and disposed
at predetermined intervals in a circumferential direction of the rotor to partition
an annular gap formed between the rotor and the peripheral wall portion of the tablet
container into a plurality of tablet receiving portions formed at an equal pitch.
A through hole is formed in the peripheral wall portion of the tablet container at
a position above the partition walls and upward from the discharge port. The tablet
cassette for a tablet feeder according to the present invention also includes: a rotary
member formed from an elastic member or a flexible member that is easily deformable,
and having a center of rotation at a center of a rotary peripheral portion of the
rotary member, whereby a part of the rotary peripheral portion is inserted into the
tablet container through the through hole; and a support structure that supports the
rotary member so as to be rotatable about the center of rotation with the part of
the rotary peripheral portion penetrating the through hole. The position of the through
hole and geometric dimensions of the rotary member are determined such that when one
of the plurality of tablet receiving portions comes to a location closet to the discharge
port due to the rotation of the rotor, one or more extra tablets that protrude out
of the one of the plurality of tablet receiving portions abut on the part of the rotary
peripheral portion, thereby preventing the one or more extra tablets from falling
into the discharge port.
[0023] In the present invention, the rotary member is used as the fall prevention member.
[0024] The tablet cassette for a tablet feeder according to the present invention described
above takes over the properties to prevent undesirable fall of two tablets at a time
by gently pushing tablets, which are entirely or partially received in a tablet receiving
portion but which are not the lowermost one and therefore should not fall and be discharged,
from the outer peripheral side toward the inner peripheral side by using the elastic
repulsive force of the rotary member that serves as the fall prevention member. Since
the fall prevention member has been changed from an endless belt to the rotary member
that is supported so as to be rotatable about the center of rotation, the rotary member
is centrally supported at one location, rather than a plurality of locations, thereby
reducing the number of axial rotation members . In the present invention that adopts
the rotary member, an arcuate projecting portion is inserted into the through hole,
which provides a further advantage that the slit length of the through hole can be
reduced, in contrast with the related art in which the endless belt is adopted and
a through hole of a slit shape will accordingly be long enough to allow insertion
of a straight tense portion of the belt.
[0025] The rotary peripheral portion of the rotary member may have a circular outline shape.
The rotary peripheral portion of the rotary member may have an outline shape in which
a plurality of projecting portions are arranged at constant intervals in a circumferential
direction.
[0026] The support structure may include a support member and a shaft holding member. The
support member is unitarily formed of a reinforcing member and a shaft portion. The
reinforcing member is harder than the rotary member, and is shaped in a thin circular
plate to support the rotary member from below, and the shaft portion is rotatable
about the center of rotation. The shaft holding member is disposed outside the tablet
container to rotatably hold the shaft portion. The rotary member is supported from
below by the reinforcing member that is hard and thin and is shaped in a circular
plate. Thus, when the rotary member is deformed as the tablets to be prevented from
falling abut on the rotary member, the rotary member tends to be deformed upward,
rather than downward. Therefore, the tablets to be prevented from falling are gently
retained while being lifted up, thereby improving the fall prevention effect. Alternatively,
the support structure may include: a reinforcing member that is harder than the rotary
member and is shaped in a thin circular plate to support the rotary member from below;
a bearing that rotatably supports the rotary member and the reinforcing member; and
a shaft holding member disposed outside the tablet container and fitted with both
ends of a shaft portion supported by the bearing to hold the shaft portion.
[0027] Further, the reinforcing member is preferably smaller in diameter than the rotary
member. Since the reinforcing member is smaller than the rotary member, the reinforcing
member and the tablets never or seldom interfere with each other, which makes it easy
to support the rotary member from below and also to support buffer the shock of the
abutment on the tablets.
[0028] An annular groove may be formed in a portion of the outer peripheral portion of the
rotor that faces the rotary peripheral portion of the rotary member, and an annular
buffer member formed from an elastic member or a flexible member that is easily deformable
may be fitted with the annular groove. Not only the rotary member that presses the
tablets to be prevented from falling against the rotor but also the corresponding
portion of the rotor that receives such tablets gently abuts on the tablets with an
elastic repulsive force, thereby improving the buffering effect.
[0029] An annular groove may be formed in a portion of the outer peripheral portion of the
rotor that faces the rotary peripheral portion of one or both of the rotary member
and the reinforcing member, and an annular buffer member formed from an elastic member
or a flexible member that is easily deformable may be fitted with the annular groove.
The buffering effect is improved even when the reinforcing member is attached to the
rotary member, by adjusting the width of the buffer member to the width of abutment
of the rotary member and the reinforcing member according to the attachment of the
reinforcing member to the rotary member.
BRIEF DESCRIPTION OF DRAWINGS
[0030]
Fig. 1 generally illustrates the structure of a tablet cassette according to a first
embodiment of the present invention; specifically Fig. 1A is a perspective view illustrating
the appearance of the tablet cassette, Fig. 1B is a perspective view illustrating
the appearance of the tablet cassette with a frame portion of a fall prevention unit
removed, Fig. 1C is a perspective view illustrating the appearance of the fall prevention
unit, and Fig. 1D is a plan view of the tablet cassette with a lid removed.
Fig. 2A is a perspective view illustrating the appearance of a rotor, and Fig. 2B
is a vertical sectional view (as taken along line A-A) of the tablet cassette, illustrating
a discharge port for tablets and a portion above the discharge port.
Fig. 3 is a vertical sectional view of a fall prevention unit using a bearing.
Fig. 4 generally illustrates the structure of a tablet cassette according to a second
embodiment of the present invention; specifically, Fig. 4A is a perspective view illustrating
the appearance of a fall prevention unit as seen from above, Fig. 4B is a perspective
view illustrating the appearance of the fall prevention unit as seen from below, and
Fig. 1C is a vertical sectional view of the tablet cassette, illustrating a discharge
port for tablets and a portion above the discharge port.
Fig. 5 is a plan view of a rotary member according to a third embodiment of the present
invention.
DESCRIPTION OF EMBODIMENTS
[0031] Tablet cassettes for a tablet feeder according to the first to third embodiments
of the present invention will be described to show specific configurations of the
present invention.
[0032] In the drawings, for the sake of clarity etc., fasteners such as bolts and couplers
such as hinges are not illustrated, and components that are necessary for or related
to the description of the present invention are mainly illustrated.
First Embodiment
[0033] A specific configuration of a tablet cassette according to a first embodiment of
the present invention will be described with reference to the drawings. Fig. 1 generally
illustrates the structure of a tablet cassette 10. Specifically, Fig. 1A is a perspective
view illustrating the appearance of the tablet cassette 10, Fig. 1B is a perspective
view illustrating the appearance of the tablet cassette 10 with a unit frame portion
25 of a fall prevention unit 20 removed, Fig. 1C is a perspective view illustrating
the appearance of the fall prevention unit 20 which is held by the unit frame portion
25, and Fig. 1D is a plan view of the tablet cassette 10 with a lid 11 removed. Fig.
2A is a perspective view illustrating the appearance of a rotor 30, and Fig. 2B is
a vertical sectional view (as taken along line A-A) of the tablet cassette 10, illustrating
a discharge port 14 for tablets and a portion above the discharge port 14.
[0034] The tablet cassette 10 includes an improved fall prevention member etc., and follows
the tablet cassette according to the related art discussed earlier as a whole.
[0035] The tablet cassette 10 includes a tablet container 12 and a rotor 30. The tablet
container 12 is configured to contain a large number of tablets supplied with its
top lid 11 opened. The tablets are contained in the internal space of the tablet container
12. The rotor 30 is axially rotatably provided in the tablet container 12 and having
a rotation transmission shaft 32 configured to receive drive from the outside. An
annular gap (15, ..., 15), in which the tablets are to be aligned, is formed between
the tablet container 12 and the rotor 30. A bottom wall portion 13 defining a lower
end portion of the annular gap has a discharge port 14 formed therein to penetrate
the bottom wall portion 13 to allow the tablets to fall down.
[0036] In order to partition the annular gap into spaces each receiving one tablet, a plurality
of partition walls 31 of a blade shape are formed at an equal pitch on an outer peripheral
portion 30a of the rotor 30 to project into the annular gap, and spaces between adjacent
partition walls 31, 31 serve as a plurality of tablet receiving portions 15 configured
to each receive one tablet which has fallen from above the rotor 30.
[0037] When the tablet cassette 10 is mounted to a base or the like (a drive portion), not
illustrated, the rotation transmission shaft 32 of the rotor 30 is engaged with a
rotation transmission shaft of the drive portion to be rotationally driven, and the
tablets that are received in the tablet receiving portions 15 consecutively fall through
the discharge port 14 along with axial rotation of the rotor 30.
[0038] Through improvement of the fall prevention member etc., the tablet cassette 10 includes
a rotary member 22, rather than the partition plate or the endless belt discussed
earlier, as the fall prevention member. In the present embodiment, the rotary member
22 is a circular plate member that includes a rotary peripheral portion 22a having
a circular outline shape. The rotary member 22 is formed from an elastic material
or a flexible material that is easily deformable. The rotary member 22 is combined
with a support member 21 to constitute the fall prevention unit 20. Here, the support
member includes a shaft portion 21a and a circular plate-shaped reinforcing member
23 that are unitarily formed, and the shaft portion 21a is configured to axially rotatably
support the rotary member 22. In the present embodiment, the fall prevention unit
20 is rotatably held by the unit frame portion 25 that constitutes a shaft holding
member that is removably attached to the tablet container 12 from the outer lateral
side. Thus the rotary member 22 is conveniently replaceable. In the present embodiment,
the support member 21 and the unit frame portion 25 constitute a support structure
configured to rotatably hold the rotary member 22.
[0039] With the introduction of the rotary member 22, a small through hole 12a of a horizontally
long slit shape is formed in a peripheral wall portion 13a of the tablet container
12 at a position above the partition walls 31 and upward from the discharge port 14.
The slit length of the through hole 12a of the tablet cassette 10 according to the
present embodiment is shorter than at least that of the through hole of the tablet
cassette with the endless belt described in Patent Document 6.
[0040] Further, the rotor 30 includes a buffer member 33, and the buffer member 33 extends
around a part of the outer peripheral portion 30a of the rotor 30 above the partition
walls 31, ..., 31.
[0041] The structural portions will be discussed in detail below.
[0042] The fall prevention unit 20 includes the support member 21, the rotary member 22,
and the circular plate-shaped reinforcing member 23, and is removably attached to
the tablet container 12, and the fall prevention unit 20 is held by the unit frame
portion 25. In the present embodiment, the shaft holding member is the unit frame
portion 25, and the support member 21, the circular plate-shaped reinforcing member
23, and the unit frame portion 25 constitute a support structure (21, 23, 25). The
support member 21 is a vertical shaft body, and is held by the unit frame portion
25 at both its upper and lower end portions engaged with the unit frame portion 25.
In the present embodiment, the shaft portion 21a of the support member 21 is axially
rotatably supported by the unit frame portion 25 from the viewpoint of placing emphasis
on cost reduction. As illustrated in Fig. 3, however, only one bearing 21b may be
provided at the middle portion of the shaft portion 21a of the support member 21,
and the rotary member 22 and the circular plate-shaped reinforcing member 23 may be
attached to the outer peripheral portion of the bearing 21b when emphasis is placed
on smooth axial rotation. With such a structure, both the members 22 and 23 are smoothly
rotatable, being orthogonal to the shaft portion 21a of the support member 21.
[0043] The rotary member 22 is a fall prevention member of a circular plate shape formed
from an elastic member or a flexible member that is easily deformable. In this embodiment,
the rotary member 22 is prepared by punching a flat plate of stretchable sponge into
an annular shape. The rotary member 22 is externally fitted with the shaft portion
21a of the support member 21. When the rotary peripheral portion 22a of the rotary
member 22 is pushed in the circumferential direction, the rotary member 22 is lightly
rotated about the shaft portion 21a.
[0044] In this embodiment, the circular plate-shaped reinforcing member 23 has the same
diameter as that of the rotary member 22, is thinner than the rotary member 22, and
is formed in a circular plate unitarily with the shaft portion 21a. If the bearing
21b is used as illustrated in Fig. 3, the circular plate-shaped reinforcing member
23 can be prepared by punching a thin flat plate made from metal or hard plastic into
an annular shape. In the structure in Fig. 3, the circular plate-shaped reinforcing
member 23 is externally fitted with the bearing 21b for the shaft portion 21a of the
support member 21, and is located directly under the rotary member 22 to support the
rotary member 22 from below and to lightly rotate about the shaft portion 21a together
with the rotary member 22.
[0045] Then, the unit frame portion 25 that is combined with the fall prevention unit 20
is held by a hand; a portion of the fall prevention unit 20 that is exposed from the
unit frame portion 25 is directed toward the through hole 12a of the tablet container
12; and the exposed rotary peripheral portions 22a and 23a of the rotary member 22
and the circular plate-shaped reinforcing member 23 are each inserted into the through
hole 12a. When the unit frame portion 25 is mounted to the tablet cassette 10 from
the outside, the support member 21 of the fall prevention unit 20 is disposed directly
outside the tablet container 12. As a result, a part of the rotary peripheral portion
23a of the circular plate-shaped reinforcing member 23 and a part of the rotary peripheral
portion 22a of the rotary member 22 of the support member 21 enter the internal space
of the tablet container 12 through the through hole 12a and are situated above the
discharge port 14.
[0046] In the present embodiment, the through hole 12a is formed at a position of the tablet
container 12 to face the annular gap between the rotor 30 and the tablet container
12, slightly higher than the partition walls 31 of the rotor 30, and slightly higher
than one tablet that has entered the tablet receiving portion 15, as with the through
hole for insertion of the partition plate or the endless belt according to the related
art. Therefore, among tablets received in one of the large number of tablet receiving
portions 15, ..., 15 that has come closer to the discharge port 14 due to axial rotation
of the rotor 30, the lowermost tablet falls through the discharge port 14 without
interfering with the fall prevention unit 20. A tablet overlying the lowermost tablet
and at least partially protruding out of the tablet receiving portion 15 abuts on
the respective rotary peripheral portions 22a and 23a of the rotary member 22 and
the circular plate-shaped reinforcing member 23, and goes over the circular plate-shaped
reinforcing member 23 while depressing the abutting portion of the rotary member 22.
Thus, the fall prevention unit 20 prevents fall of two tablets at a time into the
discharge port 14.
[0047] An annular groove is formed in a portion (a part of the outer peripheral portion)
of the outer peripheral portion 30a of the rotor 30 that faces the respective rotary
peripheral portions of the rotary member 22 and the circular plate-shaped reinforcing
member 23 of the fall prevention unit 20 discussed above. The annular groove completely
extends around the outer peripheral portion 30a of the rotor 30. The annular buffer
member 33 is fitted with the annular groove. The buffer member 33 is made from an
elastic member or a flexible member that is easily deformable. In this embodiment,
the buffer member 33 is made from sponge as with the rotary member 22. In this embodiment,
the thickness of the buffer member 33 is the same as the total thickness of the rotary
member 22 and the circular plate-shaped reinforcing member 23 that face the buffer
member 33. However, the thickness of the buffer member 33 may be larger than the total
thickness of the rotary member 22 and the circular plate-shaped reinforcing member
23.
[0048] The use and operation of the tablet cassette 10 according to the first embodiment
will be described with reference to Figs. 1 and 2 discussed above.
[0049] Tablet dispensing apparatuses and the like often handle a variety of tablets such
as tablets of a circular plate shape, halved tablets obtained by cutting the tablets
of a circular plate shape, and tablets of different shapes. It is desirable to use
the same tablet container 12 and bottom wall portion 13 of the tablet cassette 10
for tablets of various shapes as far as it is possible in consideration of storage
in the tablet dispensing apparatus, commonality of parts, etc. For this purpose, an
appropriate rotor 30 is selected to handle tablets of various types. Such rotor 30
is selected as the one with the tablet receiving portions 15 that are slightly larger
than the tablets such as the halved tablets so that the tablet receiving portions
15 each receive one tablet.
[0050] When forming the through hole 12a in the tablet container 12, a slit of such a size
that allows insertion of the respective rotary peripheral portions 22a and 23a of
the rotary member 22 and the circular plate-shaped reinforcing member 23 of the fall
prevention unit 20 is formed at a location slightly above the partition walls 31 of
the rotor 30.
[0051] When mounting the fall prevention unit 20 to the tablet container 12, the fall prevention
unit 20 is mounted to the tablet container 12 while inserting the respective rotary
peripheral portions 22a and 23a of the rotary member 22 and the circular plate-shaped
reinforcing member 23 into the through hole 12a described above from the outside.
[0052] Then, when the rotor 30 is axially rotated according to drive of the drive portion
in the base of the tablet dispensing apparatus or the like with a large number of
tablets such as halved tablets already received in the tablet container 12, the tablets,
which have been stirred on the upper surface of the rotor 30, slide down into the
annular gap that is formed between the rotor 30 and the tablet container 12, and then
are received in the tablet receiving portions 15 with one tablet in one tablet receiving
portion 15. As a result, the tablets are aligned in the plurality of tablet receiving
portions 15, ..., 15 that are circularly arranged, and are sequentially moved toward
a location above the discharge port, following an arcuate track together with the
tablet receiving portions 15.
[0053] At that time, tablets that have slid down to the tablet receiving portions 15 already
occupied by other tablets, do not reach the respective inner bottoms of the tablet
receiving portions 15. Thus, the tablets abut on the rotary member 22 of the fall
prevention unit 20 before a location above the discharge port 14, recess the rotary
peripheral portion of the rotary member 22, and are sequentially moved to a location
above the discharge port 14 together with the abutting portion of the rotary member
22 of the fall prevention unit 20 as the rotary member 22 is rotationally moved.
[0054] Then, each time the tablet receiving portion 15 in which tablets are received comes
to a location right above the discharge port 14, the lowermost one of the tablets
falls from the tablet receiving portion 15 and is discharged downward through the
discharge port 14.
[0055] In contrast, even if a tablet overlying the lowermost tablet is partially received
in the tablet receiving portion 15, a portion of the tablet protruding out of the
tablet receiving portion 15 is pushed from the outer peripheral side toward the inner
peripheral side of the annular gap by the rotary member 22, and then is pushed from
the inner peripheral side toward the outer peripheral side of the annular gap by the
buffer member 33 as a counter-action. Therefore, tablets other than the lowermost
tablet are gently sandwiched between the rotary member 22 and the buffer member 33,
either of which is easily recessed.
[0056] At that time, the rotary member 22 is deformed such that its thickness is increased
to compensate for the recess. Since the rotary member 22 is supported by the circular
plate-shaped reinforcing member 23 from below, a portion of the rotary member 22 that
is deformed to be recessed radially due to abutment with the tablets is suppressed
from being deformed downward as the thickness increases to compensate for the recess.
Thus the rotary member 22 is inevitably recessed radially as the thickness is likely
to increase upward.
[0057] Therefore, the tablets other than the lowermost tablet that should be prevented from
falling are held so as to be slightly lifted up, and reliably carried over the discharge
port 14 without being damaged. Even if the lower part of a tablet that should be prevented
from falling interferes with the circular plate-shaped reinforcing member 23, the
tablet is also gently held by the lift-up action due to the upward deformation of
the rotary member 22 and the relieving action due to the deformation of the buffer
member 33, and is also carried over the discharge port 14 without being damaged.
[0058] Then, the tablet that is gently sandwiched between the rotary member 22 and the buffer
member 33 is reliably held above the tablet receiving portion 15 without being damaged
until after the tablet passes through a location above the discharge port 14 even
if the tablet receiving portion 15 below is emptied. Thus, there is no fear that two
tablets fall at a time.
[0059] After the sandwiched tablet passes over the discharge port 14, the abutting portion
and the acting portion of the rotary member 22 are separated from those of the buffer
member 33, thereby loosening the sandwiching of the tablet. Further, when the tablet
is released from sandwiching, the released tablet falls down to be swiftly received
in the tablet receiving portion 15 below.
[0060] In the manner described above, the tablets are consecutively discharged rapidly and
accurately.
Second Embodiment
[0061] A specific configuration of a tablet cassette according to a second embodiment of
the present invention will be described with reference to the drawings. Fig. 4A is
a perspective view illustrating the appearance of a fall prevention unit 40 as seen
from above, Fig. 4B is a perspective view illustrating the appearance of the fall
prevention unit 40 as seen from below, and Fig. 4C is a vertical sectional view of
the tablet cassette, illustrating a discharge port 14 for tablets and a portion above
the discharge port 14.
[0062] The tablet cassette of this embodiment differs from that according to the first embodiment
discussed above in that the fall prevention unit 20 is replaced with the fall prevention
unit 40. The fall prevention unit 40 differs from the fall prevention unit 20 in that
a circular plate-shaped reinforcing member 43 is smaller in diameter than the circular
plate-shaped reinforcing member 23, and that the space generated by the reduction
in the diameter is occupied by a rotary member 42 that replaces the rotary member
22.
[0063] In this case, a tablet abuts on the rotary member 42 before abutting on the circular
plate-shaped reinforcing member 43 since the outside diameter of the circular plate-shaped
reinforcing member 43 is smaller than that the outside diameter of the rotary member
42 while maintaining the function of the circular plate-shaped reinforcing member
43 to support the rotary member 42 from below. As a result, the tablet hardly abuts
directly on the circular plate-shaped reinforcing member 43, and therefore there is
no need at all for concern that the tablet is strongly pressed by the circular plate-shaped
reinforcing member 43 and may be damaged.
Third Embodiment
[0064] A specific configuration of a tablet cassette according to a third embodiment of
the present invention will be described with reference to the drawing. Fig. 5 is a
plan view of a rotary member 52.
[0065] This tablet cassette of this embodiment differs from that according to the first
embodiment discussed above in that the rotary member 22 is replaced with the rotary
member 52. The rotary member 52 differs from the rotary member 22 in that a rotary
peripheral portion 52a of the rotary member 52 has an outline shape in which a plurality
of projecting portions 52b are arranged at constant intervals in the circumferential
direction while the rotary peripheral portion 22a of the rotary member 22 has a circular
outline shape.
[0066] In this case, when the rotary member 52 is rotated, the respective distal ends (portions
that are the farthest from the center of the rotary peripheral portion 52a of the
rotary member 52) of the plurality of projecting portions 52b are moved on a circular
track. Therefore, the rotary member 52 acts substantially uniformly to gently push
a tablet from the outer peripheral side toward the inner peripheral side of the rotor
30.
[Other Embodiments]
[0067] In the first to third embodiments described so far, the tablet cassette is removably
attachable, and is manually mounted to a base or the like (a drive portion) to complete
a tablet feeder. However, the combination of a tablet cassette and a drive portion
is not limited to these embodiments. For example, not only the tablet cassette but
also the drive portion may be movable or portable. In addition, the tablet cassette
and the drive portion may be automatically correlated with, mounted to, and separated
from each other. The tablet cassette may be fixed to the drive portion to form an
integral tablet feeder.
INDUSTRIAL APPLICABILITY
[0068] The tablet cassette for a tablet feeder according to the present invention may be
used in a device in which a large number of drive portions are incorporated in a storage
portion as in a medicine dispensing apparatus (see Patent Documents 1 to 3, for example),
and also in a device in which only one drive portion is mounted such as a tablet splitting
apparatus (see Patent Document 5, for example).
[0069] If the tablet cassette is removable, one tablet cassette for a tablet feeder can
be selectively attached to one of several drive portions to be used, and one of several
tablet cassettes for a tablet feeder can be selectively attached to one drive portion
to be used.
[0070] Further, the tablets are not limited to tablets in a circular plate shape and halved
tablets discussed above, and tablets of various types such as oddly shaped tablets
and capsules can be handled without inconvenience.
Description of Reference Numerals
[0071]
- 10
- tablet cassette
- 11
- lid
- 12
- tablet container
- 12a
- through hole
- 13
- bottom wall portion
- 13a
- peripheral wall portion
- 14
- discharge port
- 15
- tablet receiving portion (annular gap)
- 20
- fall prevention unit
- 21
- support member
- 21a
- shaft portion
- 21b
- bearing
- 22
- rotary member (fall prevention member)
- 22a
- rotary peripheral portion
- 23
- circular plate-shaped reinforcing member
- 23a
- rotary peripheral portion
- 25
- unit frame portion (shaft holding member)
- 30
- rotor
- 30a
- outer peripheral portion
- 31
- partition wall
- 32
- rotation transmission shaft
- 33
- buffer member (annular groove)
- 40
- fall prevention unit
- 42
- rotary member (fall prevention member)
- 43
- circular plate-shaped reinforcing member
- 52
- rotary member (fall prevention member)
- 52a
- rotary peripheral portion
- 52b
- projecting portion