Method for filling two-part capsules, each with an upper capsule part and a lower capsule part, using a capsule filling machine

Abstract

The invention relates to a capsule filling machine for filling two-part capsules, each consisting of a capsule top and a capsule bottom. The capsule filling machine comprises a main drive unit (4) for operating the capsule filling machine (1) and a closing device (23) for closing the capsule top (31) and capsule bottom (32). The capsule filling machine (1) includes a capsule top holder (33) for the capsule top (31) and a capsule bottom holder (34) for the capsule bottom (32). The closing device (23) comprises at least one first closing element (26) for exerting an insertion force (FS) acting on the capsule (10) and at least one second closing element (27) for exerting a counterforce (FG) acting against the insertion force (FS).The locking device (23) comprises an auxiliary drive unit (24) designed separately from the main drive unit (4), wherein the at least one first locking element (26) is driven by means of the auxiliary drive unit (24).

Description

[0001] The invention relates to a method for filling two-part capsules, each with a capsule top and a capsule bottom, using a capsule filling machine.

[0002] Capsules are used primarily in the pharmaceutical sector, but also in the field of dietary supplements, to administer measured amounts of a powdery, granular, or liquid preparation. The capsules consist of hard gelatin or similar materials and dissolve after being swallowed, releasing their contents.

[0003] In the case of so-called plug-in capsules, timed capsule filling machines first feed in empty capsules, which are positioned upright in capsule holders and then opened. In one or more dosing stations, the open-topped capsule bottoms are filled with the intended product in a measured quantity. The previously removed capsule tops are then attached to the filled capsule bottoms in a closing station. The resulting filled capsules are then removed from their holders in an ejection station and sent for further processing, in particular packaging.

[0004] Capsule filling machines are known that are designed as rotary machines with a rotating table. These machines have a drive unit that powers the rotary table, thereby transporting the capsules from station to station. The stations are stationary and arranged at equal angular intervals around the rotary table. Handling, especially opening and closing the capsules, requires precise coordination of the individual machine elements. Otherwise, damage to the capsules and their rejection may result. Therefore, in known rotary machines, the closing device is mechanically coupled to the rotary table, for example, by a cam, so that the closing device is also driven by the rotary table's drive unit. Depending on the rotation angle of the rotary table, the sliding elements of the closing device bring the capsule tops and bottoms together and close them.The mechanical coupling between the rotary table and the closing device ensures precise interaction between the two units.

[0005] Capsule filling machines with a main drive unit for operating the capsule filling machine and an auxiliary drive unit designed separately from the main drive unit for driving a closing device are known from US 8,596,025 B2, US 2008 / 0236106 A1, US 3,978,640 A, US 4,615,165 A, EP 2 490 649 B1, US 10 935 415B2 and EP 1 547 570 A1.

[0006] A disadvantage of such capsule filling machines is the complex setup required for adjustments such as the stroke of the slide elements. If a new batch of capsules is to be produced, the slide elements may even need to be changed due to different capsule sizes. This is time-consuming and costly.

[0007] The invention is based on the objective of further developing a method for filling two-part capsules, each with a capsule top and a capsule bottom, using a capsule filling machine in such a way that flexible production is enabled while simultaneously allowing fast changeover times.

[0008] This problem is solved by a method having the features of claim 1.

[0009] The capsule filling machine for filling two-part capsules, each consisting of a capsule top and a capsule bottom, comprises a main drive unit for operating the machine and a closing device for sealing the capsule top and bottom. The machine includes a capsule top holder for the capsule top and a capsule bottom holder for the capsule bottom. The closing device comprises at least one first closing element for exerting an insertion force on the capsule and at least one second closing element for exerting a counterforce to the insertion force. The closing device includes an auxiliary drive unit separate from the main drive unit, with the at least one first closing element being driven by the auxiliary drive unit.

[0010] The first sealing element of the closing device is therefore not driven by the main drive unit, but by a separate auxiliary drive unit. Thus, the first sealing element is not kinematically coupled to the main drive unit, in particular to the rotary table of the capsule filling machine. The kinematics of the first sealing element can be easily and individually adapted to the production conditions. This allows production fluctuations to be compensated for without having to mechanically readjust the first sealing element. For example, when converting the capsule filling machine to fill capsules of different sizes, the travel distance of the first sealing element can be adjusted. Replacing the first sealing element with one of a different geometry is not necessary. Furthermore, the speed of the first sealing element can also be adjusted to the capsule contents.This is particularly useful for products that are difficult to fill. For example, if the capsules are to be filled with a liquid, the closing speed of the first sealing element can be reduced to prevent spillage. Similarly, with particularly dusty products, dust accumulation in the machine can be reduced.

[0011] Another application involves calibrating the AMV sensors (not shown) of the filling stations. The empty capsules are weighed on a weighing device of the capsule filling machine, then filled and weighed again. The measured tare weight of the empty capsule is subtracted from the gross weight of the filled capsule to determine the net weight of the contents. This net weight is then compared with the readings from the AMV sensors, and the AMV sensors are subsequently calibrated.

[0012] In gross tare weighing, the capsule to be weighed is first fed into a capsule segment of the capsule filling machine via the insertion station. In this production step, the capsule is in a pre-sealed position – hereinafter referred to as pre-sealing. In this position, the capsule can be mechanically separated into its two halves. If, however, the capsule is filled, it is completely sealed – hereinafter referred to as full sealing. In full sealing, the capsule bottom is inserted deeper into the capsule top than in pre-sealing. In gross tare weighing, however, the capsule is not filled after the separation process, but rather resealed empty in order to determine the tare weight of the capsule on the weighing device.Since the gross weight of the same capsule is also to be determined, it is crucial that the capsule is only pre-sealed by the closing device so that, after the tare weight has been determined, it can be mechanically separated and filled again according to the sequence of stations in the capsule filling machine. With capsule filling machines known from the prior art, the capsules had to be manually reinserted into the pre-closure. Consequently, calibrating the AMV sensors is time-consuming and costly. The capsule filling machine according to the invention makes it easy to adjust the setting of the closing path of the first closing element, allowing the capsule to be pre-sealed for determining the tare weight and fully sealed for determining the gross weight.This calibration of the AMV sensors can therefore be carried out fully automatically, without having to mechanically adjust the path of the closing elements or even replace closing elements.

[0013] Preferably, the at least one first closing element is assigned to the capsule base receptacle and the at least one second closing element to the capsule top receptacle. The capsule base receptacle is designed to hold the capsule base. Accordingly, when the capsule is closed, the first closing element acts on the capsule base and pushes it towards the capsule top. The capsule top is held in the capsule top receptacle, with the second closing element acting on the capsule top. The first closing element exerts a pushing force on the capsule base in the direction of the capsule top, with the second closing element counteracting this pushing force on the capsule top. In this way, it is ensured that the capsule base is inserted into the capsule top without the capsule top jumping out of the capsule top receptacle.

[0014] It is advantageously provided that the at least one second sealing element is operatively connected to the main drive unit. Since the second sealing element essentially serves to generate a counterforce opposing the insertion force, and individual adjustment of the movement of the second sealing element is therefore not strictly necessary, it is expedient to drive the second sealing element via the main drive. In an alternative embodiment of the capsule filling machine, it can, of course, also be provided that the sealing device includes a further auxiliary drive unit, designed separately from the main drive unit, wherein the at least one second sealing element is driven by means of this further auxiliary drive unit. The auxiliary drive unit and the further auxiliary drive unit are two independent drive units.Thus, the kinematics of the first locking element can be individually adjusted via the auxiliary drive unit, and the kinematics of the second locking element can be individually adjusted via the further auxiliary drive unit.

[0015] Preferably, the at least one first locking element is designed as a locking pin. The at least one second locking element is preferably designed as a receiving pocket. The receiving pocket ensures a secure hold of the capsule top, thus preventing it from popping out of the capsule top receptacle. Preferably, the receiving pocket is wedge-shaped or conical. This allows capsules of different sizes to be fixed in a single receptacle.

[0016] In an alternative design of the capsule filling machine, it may also be advantageous for the second closing element to be designed as a locking pin.

[0017] It is advantageous for the auxiliary drive unit to include a servo motor that acts on the first closing device. In an alternative embodiment of the capsule filling machine, it may also be expedient to provide a stepper motor instead of the servo motor. Similarly, a servo motor or a stepper motor may be provided for the second auxiliary drive unit.

[0018] The capsule filling machine preferably includes a control unit. This control unit is also specifically associated with the closing device, and the movement of the at least one first closing element can be adjusted via the control unit. The control unit also controls the auxiliary drive unit. If a further auxiliary drive unit is provided, it can also be adjusted via the control unit.

[0019] An embodiment of the invention is described in more detail below with reference to the drawing. The drawing shows: Fig. 1 shows a top view of a capsule filling machine in the embodiment according to the invention with a rotary table, with capsule segments on the rotary table and with a closing device with a drive unit; Fig. 2 shows a partial side view of the capsule filling machine according to the invention. Fig. 1 , Fig. 3 in a side view the auxiliary drive unit of the capsule filling machine according to Fig. 1 , Fig. 4 in a perspective view the auxiliary drive unit of the capsule filling machine according to Fig. 1 and Figs. 5 to 7 show partial sectional views of the capsule segment as well as the first and second closing elements during the closing process of several capsules.

[0020] Fig. 1 shows in a top view an embodiment of a capsule filling machine 1 according to the invention for filling capsules 10 ( Fig. 5 bis Fig. 7 ) with a filling material. The filling material can be in the form of a powder, granules, tablets, or the like. This can be a pharmaceutical preparation, a food supplement, or the like. The capsules 10 consist of a capsule base 32 and a capsule top 31 attached to it, both of which are made, for example, of hard gelatin.

[0021] The capsule filling machine 1 after Fig. 1 The capsule filling machine 1 comprises a rotary table 2 and a schematically represented main drive unit 4, wherein the rotary table 2 can be driven by the main drive unit 4 to rotate about a vertical axis of rotation 3 in timed steps in the direction of rotation 9. The main drive unit 4 comprises at least one electric motor which is operatively connected to and drives the rotary table 2. Preferably, the capsule filling machine 1 comprises a control unit 30 which is coupled to the main drive unit. The control unit 30 is also in Fig. 1 The diagram is shown schematically in dashed lines. A number of capsule segments 5 are arranged at uniform angular intervals on a circumferential area of ​​the rotary table 2. In the illustrated embodiment, a total of twelve capsule segments 5 are provided. A different number of capsule segments 5 may also be advantageous. Each capsule segment 5 consists of a lower segment part 6 fixed to the circumferential area of ​​the rotary table 2 and an upper segment part 7 pivotable relative to it. Several stationary machining stations 11 to 22, which do not rotate with the rotary table 2, are positioned around the rotary table 2. Fig. 1 not shown in detail. The number of processing stations 11 to 22 corresponds to the number of capsule segments 5, so that in each rotary position of the rotary table 2, which is clocked in angular increments, each capsule segment 5 lies within the access range of one of the processing stations 11 to 22.

[0022] As in Fig. 1 As shown, the capsule segments 5 of the preferred embodiment contain several capsule receptacles 8 for receiving the capsules 10. In the preferred embodiment, each capsule segment 5 contains five capsule receptacles 8. It may be advantageous to provide several capsule receptacles 8, in particular ten, preferably twelve capsule receptacles 8. In the preferred embodiment, the capsule receptacles 5 are arranged in a linear, straight row. With a large number of capsule receptacles 5, they can also be arranged in two or more such rows.

[0023] The preferred embodiment of the capsule filling machine 1 comprises an insertion station 11 in which empty capsules, initially provisionally assembled and consisting of a capsule base 32 and a capsule top 31, are inserted into the capsule receptacles 8 of the capsule segment 5. During normal operation, the attached capsule top 31 separates from the capsule base 32. The next processing station is a rejection station 12. Defective, unseparated empty capsules are rejected in the rejection station 12.

[0024] After the discharge station 12, the upper segment 7, with the capsule tops 31 held within it, is pivoted relative to the lower segment 6, with the capsule bottoms 32 held within it. Following the discharge station 12 are a total of three filling stations 13, 14, 15, in which the capsule bottoms 32 held in the lower segments 6 are filled with the intended filling material. It may also be sufficient to provide only one or two filling stations.

[0025] After passing through the last filling station 15, the upper segment 7 is pivoted back into alignment with the lower segment 6 via stations 16, 17, and 18. At closing station 18, the capsules 10 are closed by sliding the previously removed or separated capsule uppers 31 back onto the filled capsule lowers 32 and locking them into place. Several inspection stations 19 and 20 follow closing station 18. At inspection stations 19 and 20, capsules 8 are inspected and, if necessary, rejected. At a subsequent ejection station 21, the remaining capsules 10 that have been found to be good are ejected by means of a plunger or other ejection device (not shown).

[0026] As in Fig. 1 As shown, the capsule filling machine 1 includes a closing device 23, wherein the capsules 10 are resealed at the closing station 18 by means of the closing device 23. The closing device 23 is described below with reference to the Fig. 2 bis 4 described: As in the Fig. 2 bis 4 As shown, the locking device 23 comprises an auxiliary drive unit 24, which is designed separately from the main drive unit 4, and thus the auxiliary drive unit 24 is completely mechanically decoupled from the main drive unit 4. Furthermore, the locking device 23 comprises at least one first locking element 26 driven by the auxiliary drive unit 24. The locking element 26 is designed such that, when the capsule 10 is closed, it exerts a clamping force FS on the capsule lower part 32, more precisely on the base of the capsule lower part 32, in the direction of the segment upper part 7.

[0027] The auxiliary drive unit 24 comprises an electric motor 40 and a linear actuator 45 driven by the electric motor 40. The electric motor 40 is connected to a drive shaft 42 via a coupling 41. In the preferred embodiment, the coupling 41 is designed as a bellows coupling; however, other coupling types may also be suitable. The drive shaft 42, in turn, acts on the linear actuator 45 via a gearbox 43. In this embodiment, the linear actuator 45 is designed as a threaded spindle. At one end, the linear actuator 45 is connected to a lower retaining plate 35 for the at least one locking element 26. The linear actuator 45, driven by the electric motor 40, can raise and lower the retaining plate 35. As shown in Fig. 2 As shown, all components of the auxiliary drive unit 24 are attached either directly to a rigid table 37 of the capsule filling machine 1 or via a mounting frame 38 arranged on the table 37. In an alternative embodiment, it may be advantageous to provide other machine elements for the auxiliary drive unit 24. However, it is essential that the auxiliary drive unit 24 is mechanically decoupled from the main drive unit 4 and that the at least one first sealing element 26 can be driven by the auxiliary drive unit 24 in the form of a linear movement.

[0028] The auxiliary drive unit 24, in particular its electric motor 40, is the one in Fig. 2 The control unit 30 is only schematically indicated. Accordingly, movement parameters such as travel distance, speed, acceleration, etc., of the first capping element 26 can be set via the auxiliary drive unit 24 using the control unit 30. Since the auxiliary drive unit 24 is mechanically completely decoupled from the main drive unit 4, the aforementioned parameters can be set independently of the rotary movement of the rotary table 2. Thus, the movement parameters can be easily adapted to the process parameters via the control unit 30 without having to make any mechanical adjustments to the capsule filling machine 1, such as changing a capping element 26. Process parameters can be, as already described, the product to be filled, the quantity of the product, the capsule size, etc.

[0029] As especially in the Fig. 5 bis 7 As shown, the at least first closing element 26 is arranged on the lower retaining plate 35, which is positioned below the lower segment part 6 with respect to gravity S. In a preferred embodiment, the retaining plate 35 has a plate-like basic geometry. In an alternative embodiment, it may also be advantageous to provide a different geometry for the retaining plate 35. In the preferred embodiment, five first closing elements 26 are arranged on the lower retaining plate 35. The number of first closing elements corresponds to the number of capsule receptacles 8; therefore, a different number of first closing elements 26 may also be advantageous. The lower retaining plate 35 is operatively connected to the auxiliary drive unit 24 such that the lower retaining plate 35 with the closing elements 26 is linearly movable when driven by the auxiliary drive unit 24.The lower retaining plate 35 is aligned with the closing elements 26 relative to the capsule receptacles 8. When a linear movement is performed by the auxiliary drive unit 24, the closing elements 26 engage in the lower segment part 6, in particular in the capsule lower part receptacles 34 formed on the lower segment part 6, and push the lower capsule part 32 upwards against gravity S in the direction of the upper segment part 7.

[0030] Furthermore, the closing device 23 comprises at least one second closing element 27. The second closing element 27 is designed such that, when the capsule 10 is closed, it exerts a counterforce FG on the capsule upper part 31 in the direction of the segment lower part 6. As shown in particular in the Fig. 5 bis 7 As shown, the at least second closing element 27 is arranged on an upper retaining plate 36, which is positioned above the upper segment part 7 with respect to gravity S. Analogous to the design of the lower retaining plate 35, in the preferred embodiment five second closing elements 27 are arranged on the upper retaining plate 36. As already described, the number of second closing elements 27 also corresponds to the number of capsule receptacles 8. The upper retaining plate 36 is aligned with the second closing elements 27 relative to the capsule receptacles 8. The upper retaining plate 36 is mechanically connected to the main drive unit 4 via a gearbox 39. Both the linear movement of the second closing elements 27 and the rotary movement of the rotary table are performed by means of the main drive unit 4. Thus, the linear movement of the second closing elements 27 is directly dependent on the rotary movement of the rotary table 2.The gearbox 39 can, for example, be designed as a cam gearbox or as a cam on the rotary table 2.

[0031] In the Fig. 5 bis 7 The closing process of the capsules 10 is shown. Fig. 5 The lower segment part 6 and the upper segment part 7 are shown overlapping, so that the lower capsule part receptacle 34 and the upper capsule part receptacle 33 are aligned with each other. The lower capsule part 31 is held in the lower capsule part receptacle 34 of the lower segment part 6, and the upper capsule part 31 is held in the upper capsule part receptacle 33 of the upper segment part 7. The first closing elements 26 are spaced apart from the lower capsule parts 32, and the second closing elements 27 are spaced apart from the upper capsule parts 31. To close the capsule halves 31, 32, the first closing elements 26 and the second closing elements 27 move together. The second closing elements 27 are moved linearly towards the lower segment part 6 via the main drive unit 4 until they contact the upper capsule parts 31. Fig. 6 ). Simultaneously, the first closing elements 26 are moved linearly towards the segment upper part 7 via the auxiliary drive unit 24 until they contact the capsule lower parts 32. The first closing elements 26 are moved further towards the segment upper part 7 and exert the insertion force FS on the capsule lower parts 32. The capsule lower parts 32 are pushed into the respective capsule upper parts 31 by means of the first closing elements 26, whereby the second closing elements 27 now exert a counterforce FG on the capsule upper parts 31 ( Fig. 7 As a result, the capsule tops 31 cannot be pushed out of the capsule top receptacle 33, thus ensuring secure closure of the capsules 10. Once the capsules 10 are closed, the first closing elements 26 and the second closing elements 27 move apart again, allowing the capsules 10 to be transported on the rotary table 2 to the next station.

[0032] In an alternative embodiment of the capsule filling machine 1, it may be advantageous to provide a separate auxiliary drive unit for the second sealing elements 27, distinct from the main drive unit 4. This would allow the movement parameters of both the first sealing elements 26 and the second sealing elements 27 to be individually adjusted.

[0033] As especially in the Fig. 5 bis 7 As shown, both the first locking elements 26 and the second locking elements 27 are designed as locking pins. In an alternative embodiment, it may also be advantageous to provide other locking elements instead of locking pins 28.

Claims

1. Method for filling two-part capsules, having in each case one capsule top part and in each case one capsule bottom part, using a capsule-filling machine, wherein the capsule-filling machine comprises a main drive unit (4), for operating the capsule-filling machine (1), and a closing device (23), for closing off the capsule top part (31) and the capsule bottom part (32), wherein the capsule-filling machine (1) comprises a capsule segment (5), and wherein the capsule segment (5) comprises a capsule-top-part receptacle (33), for the capsule top part (31), and a capsule-bottom-part receptacle (34), for the capsule bottom part (32), wherein the closing device (23) comprises at least one first closure element (26), for exerting a plugging force (FS) that acts on the capsule (10), and at least one second closure element (27), for exerting a counter-force (FG) that counteracts the plugging force (FS), wherein the closing device (23) comprises an auxiliary drive unit (24) formed separately from the main drive unit (4), wherein the at least one first closure element (26) is driven by means of the auxiliary drive unit (24), wherein the closing device (23) is assigned a controller (30), wherein the movement of the at least one first closure element (26) is settable by means of the controller (30), wherein the capsule-filling machine (1) comprises a weighing device, comprising the following steps: - supplying a capsule to be weighed to a capsule segment via an insertion station, - separating the plugged-on capsule top part (31) from the capsule bottom part (32), - adapting the movement parameters of the first closure element (26) to process parameters via the controller (30), - after the separation of the plugged-on capsule top part (31) from the capsule bottom part (32), closing off the empty capsule bottom part (32) with the capsule top part (32).

2. Method according to Claim 1, characterized in that the empty capsule is preliminarily closed off in the closing device.

3. Method according to Claim 2, characterized in that the tare weight of the capsule is determined at a weighing device.

4. Method according to Claim 3, characterized in that, after the tare weight of the capsule has been determined, the plugged-on capsule top part (31) is separated from the capsule bottom part (32) by machine.

5. Method according to one of Claims 1 to 4, characterized in that the capsule bottom part (32) is filled.

6. Method according to Claim 5, characterized in that the capsule is closed off completely, so that the capsule is in the fully closed-off state.

7. Method according to Claim 6, characterized in that the gross weight of the fully closed-off capsule is determined at the weighing device.

8. Method according to Claim 7, characterized in that the net weight of the capsule is determined by subtracting the determined tare weight of the capsule from the determined gross weight of the capsule.

9. Method according to Claim 8, characterized in that the net weight is compared with measurement values of the AMV sensors, and in particular fully automatic calibration of the AMV sensors is subsequently carried out.

10. Method according to one of Claims 1 to 9, characterized in that a closure travel of the first closure element is adapted so as to be able to preliminarily close off the capsule.

11. Method according to one of Claims 1 to 9, characterized in that a closure travel of the first closure element is adapted so as to be able to fully close off the capsule.

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