Information
-
Patent Grant
-
6390330
-
Patent Number
6,390,330
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Date Filed
Thursday, January 11, 200123 years ago
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Date Issued
Tuesday, May 21, 200222 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 222 168
- 222 1685
- 222 25
- 141 71
- 141 81
- 141 146
- 141 238
- 141 240
- 141 242
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International Classifications
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Abstract
An apparatus for metering and dispensing powder into hard gelatin capsules or the like. The apparatus has a metering disk that rotates in advancing steps, with bores disposed in its base. The bores which cooperate with tamping plungers that move up and down. The tamping plungers are disposed on a common tamping plunger support and when inserted into the bores, compress the powder into compressed pellets. In order to detect breakage of the springs and in order to be able to make a statement as to the mass of the compressed pellets, means are provided which detect the spring path of the tamping plungers immediately preceding the ejection plungers.
Description
PRIOR ART
The invention relates to an apparatus for metering and dispensing powder into hard gelatin capsules or the like as has been disclosed by DE 197 20 362 A1. In the known apparatus, the springs, which were previously coupled to the tamping plungers for the metering and compression of the powder in the bores of the metering disk, are replaced with pneumatically acting means. It is therefore possible to eliminate the danger of spring breakage and at the same time to minimize the conversion work required in a format change of the apparatus. Mention is also made of the fact that by means of pressure sensors for the pneumatic means, which are coupled to the control device of the apparatus, make it possible for there to be a monitoring/control of the tamping plungers.
However, a quantitative statement as to the powder quantities metered into the bores of the metering disk by the tamping plungers has not been possible up to this point with either the known apparatus with pneumatic means instead of the springs or with an apparatus that has springs for the tamping plungers.
ADVANTAGES OF THE INVENTION
The apparatus according to the invention for metering and dispensing powder into hard gelatin capsules or the like has the advantage over the prior art that it is possible to make a quantitative statement as to the weight of the compressed pellets formed in the bores of the metering disk. In a simple way, this permits a 100% weight control of the compressed pellets, which previously took place outside the apparatus by means of a weighing device, for example the closed hard gelatin capsules were weighed. With a 100% weight control of the hard gelatin capsules by means of the weighing device, the performance of the apparatus was limited or a number of weighing devices were required.
Other advantageous improvements of the apparatus according to the invention are disclosed herein. An embodiment set forth makes it possible, for example, to convert existing conventional tamping plungers that cooperate with mechanically acting springs. This embodiment permits both a weight control of each individual compressed pellet and also optionally permits a statement to be made as to the presence of possibly broken springs. A particularly simple format adaptation and adjustability of the apparatus are permitted. With this embodiment, the pneumatically acting means of the individual tamping plunger groups can be adjusted in order to permit a format or weight adaptation of the compressed pellets. Another embodiment permits a conversion of existing apparatuses with springs without having to insert pneumatic means.
BRIEF DESCRIPTION OF THE DRAWINGS
An exemplary embodiment of the invention is shown in the drawings and will be explained in detail in the subsequent description.
FIG. 1
is a longitudinal section through an apparatus for metering and dispensing powder into hard gelatin capsules or the like,
FIG. 2
is a simplified top view of a metering disk,
FIG. 3
is a schematic depiction for indicating the pneumatic triggering of a tamping plunger group,
FIG. 4
is a section through a metering disk in the vicinity of a tamping plunger loaded by a spring, and
FIG. 5
is a section through a metering disk in the vicinity of a tamping plunger in a modified exemplary embodiment.
DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
The apparatus
10
for metering and dispensing powder into hard gelatin capsules
1
or the like shown in
FIG. 1
has a filling material container
11
. The filling material container
11
is constituted by a casing
12
, a cover
13
, and a metering disk
14
. At the same level as the metering disk
14
, the filling material container
11
is encompassed by a ring
15
, which is used to hold capsule tops
2
. Underneath the ring
15
, segments
17
are provided, which are correspondingly embodied to hold capsule bottoms
3
. The segments
17
are supported so that they can each pivot around a bolt, not shown, fastened in the ring
15
and during the rotation through a fixed curve
20
via a curve roller
21
, are moved inward as needed, i.e. under the bores
22
of the metering disk
14
, or outward, i.e. beyond the circumference of the ring
15
. The metering disk
14
is fastened to a shaft
23
which is coupled to the drive mechanism of the apparatus
10
and rotates the metering disk
14
in advancing steps, by a respective angular amount each time. As can be seen from
FIG. 2
, the metering disk
14
has a total of four groups
18
a
to
18
d
offset from one another by 90 degrees, with five bores
22
each.
For the fastening of the curve
20
, a second ring
24
is provided, which is in turn fastened to the table top
25
of the apparatus
10
. Between the curve
20
and the metering disk
14
, an intermediary ring
26
is provided, which can be pressed against the underside of the metering disk
14
in an intrinsically known manner by adjusting means not shown. This intermediary ring
26
is used to seal the bores
22
of the metering disk
14
in the vicinity of the powder metering.
As
FIG. 1
also shows, a support
28
, which can be moved up and down by means of columns
27
and is disposed above the filling material container
11
, respectively executes a particular stroke. A number of tamping plunger supports
29
, three tamping plunger supports
29
in the exemplary embodiment, are disposed on a graduated circle of the support
28
at uniform angular intervals, each of which has five tamping plungers
30
guided in it, which pass through the cover
13
of the filling material container
11
in corresponding bores. In addition, ejection plungers
31
are disposed on the support
28
, which are connected to a retainer
32
disposed on the support
28
in such a way that they can move vertically. The ejection plungers
31
are encompassed inside the filling material container
11
by a powder deflecting body
33
that is intrinsically known and is not essential to the invention.
What is essential to the invention is the disposition, embodiment, and function of the tamping plungers
30
. In particular according to the first exemplary embodiment of the invention, at least the tamping plungers
30
immediately preceding the ejection plungers
31
when the metering disk
14
is rotated clockwise (
FIG. 2
) (i.e. in the position of the metering disk
14
shown, the tamping plungers
30
which are disposed above the group
18
d
of bores
22
) are equipped with pneumatic means instead of the conventional springs
19
(FIG.
4
). To that end, a bore
34
for each of the tamping plungers
30
is embodied in the tamping plunger support
29
associated with the tamping plungers
30
. The upper ends of the tamping plungers
30
, which are embodied as pistons
35
, are guided in a sealed fashion in the bores
34
so that they can slide for a particular distance. A stop
36
limits the maximal stroke of the pistons
35
in the direction of the metering disk
14
. The bores
34
of the tamping plunger support
29
have a common compressed air connection
37
(FIG.
3
), which is connected to a compressed air source with the interposition of a pressure regulating circuit
38
. The pressure regulating circuit
38
can be triggered by the control device
40
of the apparatus via a line
41
. In particular, the control device
40
supplies a pressure reference value P(ref) as a preset to the pressure regulating circuit
38
via the line
41
. Furthermore, the pressure chambers
42
of the bores
34
embodied above the pistons
35
are connected via lines
43
to pressure sensors
44
, which supply the measured pressure values P(actual) to the control device
40
as input values. The control unit
40
is also coupled to a weighing device
45
which supplies the weighing result M(capsule) of a hard gelatin capsule
1
to the control device
40
as an input value via another line
46
. Finally, an ejection device
48
can be triggered by means of a line
47
in order to be able to discharge individual hard gelatin capsules
1
from the apparatus
10
.
In the above-described first exemplary embodiment of the invention, only the tamping plungers
30
immediately preceding the ejection plungers
31
(in the vicinity of the bore group
18
d
) are provided with the above-described pressure sensors
44
. However, according to
FIG. 4
, the other two groups of tamping plungers
30
are equipped with conventional springs
19
, which act via the tamping plunger support
29
, for example on the top ends of the tamping plungers
30
.
The above-described apparatus
10
functions as follows: In order to form the compressed pellets in the bores
22
from the powder disposed in the filling material container
11
, the metering disk
14
is rotated in advancing clockwise steps under the tamping plungers
30
of a tamping plunger support
29
. Then with a downward motion of the support
28
, the tamping plungers
30
are inserted into the bores
22
of the metering disk
14
, wherein the powder disposed in the bore
22
is compressed. During the compression or pressing of the powder, the intermediary ring
26
constitutes a counter support for the tamping plungers
30
and the powder. Then, the tamping plungers
30
are moved back out of the bores
22
of the metering disk
14
, whereupon the metering disk
14
is rotated into the vicinity of the next tamping plunger support
29
. After the last pressing action, the compressed pellets thus produced travel into the vicinity of the ejection plungers
31
where they are slid into the capsule bottoms
3
supplied by the segments
17
. Then the capsule bottoms
3
are brought back together with the capsule tops
2
.
The weight or mass of the compressed pellets formed in the bores
22
by the tamping plungers
30
and consequently the mass M(capsule) of the hard gelatin capsules
1
is determined on the one hand by the stroke of the tamping plungers
30
(produced by the stroke of the support
28
), and is determined on the other hand by the spring ratio of the springs
19
cooperating with the tamping plungers
30
as well as the level of the pressure reference value P(ref). The greater the spring ratio of the springs
19
and the higher the pressure reference value P(ref), the less the tamping plungers
30
of the last tamping plunger group are deflected into the bores
22
, i.e. the greater the density of the powder in the bores
22
and consequently the greater the mass of the compressed pellets as well.
It is now essential that by means of the pressure values P(actual) measured by the pressure sensors, which values correspond to the corresponding spring paths of the tamping plungers
30
, for one thing, a statement can be made as to whether for example one of the springs
19
cooperating with the tamping plungers
30
is broken and for another, whether the mass of the compressed pellets in the bores
22
is within preset tolerances. This can be explained in that with correctly functioning springs
19
and a correct preset pressure reference value P(ref), the pressure value P(actual) and the spring path when a tamping plunger
30
is inserted into a bore
22
is increased by a particular amount or has a particular characteristic course. The level or course of the pressure value P(actual) consequently corresponds to the level or course of the spring path of a tamping plunger
30
. When a spring
19
breaks, however, the powder disposed in a bore
22
is compressed much less or not at all by the corresponding tamping plunger
30
so that the last tamping plunger
30
coupled to the pressure sensor
44
is inserted more forcefully into the corresponding bore
22
since the powder has been compressed less beforehand. As a result, however, with its insertion, the measured pressure value P(actual) increases by only a slight amount and has a different characteristic curve. The breaking of a spring
19
can consequently be detected by virtue of the fact that the pressure value P(actual) is compared to a pressure value stored in the control device
40
.
In addition, by means of the weighing device
45
, the mass M(capsule) of a hard gelatin capsule
1
can be determined, which is associated with a particular progression of pressure values P(actual) detected in succession during the insertion of a tamping plunger
30
into a bore
22
. If, for example, the determined mass M(capsule) is too high, then a lower pressure reference value P(ref) will be preset by the control device
40
so that the corresponding last tamping plunger
30
is inserted somewhat less into the bore
22
and consequently also introduces somewhat less powder. Consequently, it is possible to make a statement as to the mass of the compressed pellets by means of the pressure values P(actual) measured.
If the measured pressure value P(actual) of a compressed pellet and consequently the mass of the hard gelatin capsule
1
filled with the compressed pellet is outside predetermined tolerances, then the corresponding hard gelatin capsule
1
can be separated out by means of the ejection device
48
.
With the above-described first exemplary embodiment, it is also possible in a format change to change the mass of the compressed pellets within certain limits by changing the pressure reference values P(actual), without having to replace the springs
19
, which reduces the conversion times of the apparatus
10
.
In a second exemplary embodiment of the invention, all of the tamping plungers
30
are equipped with pneumatic means, i.e. the tamping plungers
30
do not have any springs
19
according to FIG.
4
. In accordance with the first exemplary embodiment, at least the tamping plungers
30
immediately preceding the ejection plungers
31
have pressure sensors
44
for detecting pressure values P(actual).
In order, in the second exemplary embodiment with a predetermined stroke of the support
28
, to be able to produce different pressing powers of the tamping plungers
30
on the powder and consequently different densities and volumes of the compressed pellets, different pressure reference values P(ref) are provided. Depending on the pressure reference value P(ref) that is set, a corresponding air pressure acts on the tops of the pistons
35
so that a corresponding damping degree of the tamping plungers
30
is produced. This means that with a relatively high air pressure, the tamping plungers
30
are damped relatively little so that with a downward motion of the tamping plungers
30
into the bores
22
, the powder is compressed relatively forcefully. This produces a relatively high density and mass of the compressed pellets. With a relatively low air pressure, the air disposed above the pistons
35
in the bores
34
can be compressed relatively forcefully with the compression by means of the compressed pellets. This means that a relatively low density and mass of the compressed pellets is produced.
In the third exemplary embodiment of the invention, however, all of the tamping plungers
30
have springs
19
according to FIG.
4
. However, the tamping plungers
30
immediately preceding the ejection plungers
31
are respectively equipped according to
FIG. 5
with a path sensor
50
for each tamping plunger
30
. This path sensor
50
coupled to the control device
40
of the apparatus
10
can, for example, be used as a strain gauge (DMS) or as an inductive sensor. It is only essential that the path sensor
50
detect the spring deflection characteristic curve of the tamping plungers
30
to a sufficiently precise degree when the tamping plungers
30
are inserted into the bores
22
. This path characteristic curve consequently corresponds to the characteristic curve of the pressure values P(actual). With the third exemplary embodiment, both breakage of the springs
19
and incorrect meterings can be detected.
It should also be mentioned that the wiring example shown in
FIG. 2
can be modified in numerous ways in order to permit, depending on the particular application, a more sensitive regulation of the set air pressure, for example, or a greater adjustment range.
In a modification of the first two exemplary embodiments, it is also conceivable to couple the tops of each of the tamping plungers to a membrane disposed in the tamping plunger support
29
. On one side, this membrane is acted on by a particular air pressure so that the tamping plungers
30
are damped by the membranes in accordance with the air pressure.
The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.
Claims
- 1. An apparatus (10) for metering and dispensing powder into hard gelatin capsules (1), comprising a filling material container (11) for the powder, a metering disk (14) with bores (22), which is disposed underneath the filling material container (11), the metering disk rotates in steps, and during a stop phase, comes into alignment with tamping plungers (30), the tamping plungers can be moved into and out of the bores (22) and when the tamping plungers are inserted into the bores (22), the tamping plungers dispense the powder into the bores (22) and compresses the powder, the tamping plungers (30) are disposed so that they are damped by spring means (19) or by pneumatically acting means (38, 39, 42) so that when the powder is compressed in the bores (22) the tamping plungers are deflected by a particular distance, and ejection plungers (31) following the tamping plungers (30), in which the ejection plungers transfer the compressed pellets previously formed in the bores (22) by the tamping plungers (30) into supplied capsule parts (3), at least the tamping plungers (30) immediately preceding the ejection plungers (31) have means (44; 50) for detecting the spring path of the tamping plungers (30) and that the means (44; 50) are coupled to a control device (40) which compares the detected spring paths to a spring path stored in the control device (40).
- 2. The apparatus according to claim 1, in which the tamping plungers (30) immediately preceding the ejection plungers (31) have pneumatically acting means (38, 39, 42) and that the tamping plungers (30) immediately preceding these tamping plungers (30) are coupled to springs (19).
- 3. The apparatus according to claim 2, in which the means for detecting the spring path of the tamping plungers (30) have pressure sensors (44).
- 4. The apparatus according to claim 3, in which in regard to the tamping plungers (30) cooperating with the pneumatically acting means (38, 42), the ends of the tamping plungers (30) remote from the bores (22) are embodied as pistons (35) that are guided in sliding fashion in cylinder bores (34) and are acted on by a compressed air source.
- 5. The apparatus according to claim 4, in which the cylinder bores (34) are connected by means of a common compressed air connection (37) coupled to the compressed air source (39).
- 6. The apparatus according to claim 2, in which in regard to the tamping plungers (30) cooperating with the pneumatically acting means (38, 42), the ends of the tamping plungers (30) remote from the bores (22) are embodied as pistons (35) that are guided in sliding fashion in cylinder bores (34) and are acted on by a compressed air source.
- 7. The apparatus according to claim 6, in which the cylinder bores (34) are connected by means of a common compressed air connection (37) coupled to the compressed air source (39).
- 8. The apparatus according to claim 1, in which all of the tamping plungers (30) are coupled to pneumatically acting means (38, 39, 42).
- 9. The apparatus according to claim 8, in which in regard to the tamping plungers (30) cooperating with the pneumatically acting means (38, 42), the ends of the tamping plungers (30) remote from the bores (22) are embodied as pistons (35) that are guided in sliding fashion in cylinder bores (34) and are acted on by a compressed air source.
- 10. The apparatus according to claim 9, in which the cylinder bores (34) are connected by means of a common compressed air connection (37) coupled to the compressed air source (39).
- 11. The apparatus according to claim 1, in which in regard to the tamping plungers (30) cooperating with the pneumatically acting means (38, 42), the ends of the tamping plungers (30) remote from the bores (22) are embodied as pistons (35) that are guided in sliding fashion in cylinder bores (34) and are acted on by a compressed air source.
- 12. The apparatus according to claim 11, in which the cylinder bores (34) are connected by means of a common compressed air connection (37) coupled to the compressed air source (39).
- 13. The apparatus according to claim 1, in which all of the tamping plungers (30) are coupled to spring means (19) and that the means for detecting the spring path of the tamping plungers (30) have path sensors (50).
Priority Claims (1)
Number |
Date |
Country |
Kind |
100 01 068 |
Jan 2000 |
DE |
|
US Referenced Citations (4)