Rotary press and method for cleaning same

Abstract

The invention relates to a rotary press (10), in particular a rotary tablet press, comprising a rotor (14) that can be rotated about an axis of rotation (12), and a cleaning device (16) for cleaning the rotary press (10), the cleaning device (16) comprising at least one injection opening (18), in particular a plurality of injection openings (18), for injecting a cleaning agent (20), characterized in that the cleaning agent (20) is separated from the rotor (14), in particular the plurality of injection openings (18). The cleaning device (16) is coupled to the rotor (14) and is configured to enable rotation of the injection orifice (18) about the axis of rotation (12) by rotation of the rotor (14). The invention also relates to a method for cleaning such a rotary press (10).

Description

Technical Field

[0001] The invention relates to a rotary press, in particular a rotary tablet press, having the features of the preamble of claim 1 and to a method for cleaning a rotary press, in particular a rotary tablet press, having the features of the preamble of the subordinate claims. Background Art

[0002] Tablet presses can be wet cleaned at the end of a tablet batch. The success of wet cleaning depends on whether as many surfaces as possible on the tablet press that need to be cleaned can be wetted directly with the cleaning liquid. Therefore, it is desirable to have as little spray shadow as possible between the cleaning agent nozzle and the surface to be cleaned.

[0003] To avoid jet shadows, the number of nozzles can be increased. The nozzles themselves and / or their supply lines can create their own jet shadows. This can make the arrangement of the nozzles and the tablet press itself very complicated, especially if the nozzles are arranged statically. To reduce jet shadows, the nozzles can be moved during the cleaning process.

[0004] WO 2009 / 021776 A2 discloses a cleaning device for cleaning a capsule filling machine with a rotating cleaning unit, the cleaning device having a spraying opening for spraying a cleaning agent. Summary of the invention

[0005] The object of the present invention is therefore to provide a rotary press, in particular a rotary tablet press, and a method for cleaning a rotary press, in particular a rotary tablet press, in which spray shadows are avoided or at least reduced and the design effort is kept to a minimum.

[0006] This object is achieved by a rotary press, in particular a rotary tablet press, having the features of claim 1 .

[0007] The rotary press comprises a rotor rotatable about a rotation axis. The rotor can be designed as a rotor disk. The rotor can be mounted to rotate about the rotation axis.

[0008] The rotary press also includes a cleaning device. The cleaning device is used to clean the rotary press. The cleaning device includes at least one injection port. The cleaning device particularly includes a plurality of injection ports. The injection ports are used to inject a cleaning agent. The cleaning agent may be a liquid, a gas and / or a mixture of a liquid and a gas. The cleaning agent may particularly be a cleaning liquid.

[0009] The cleaning device (or nozzle) is coupled to the rotor and is configured to rotate the nozzle about the rotation axis by the rotation of the rotor. The nozzle of the cleaning device can be designed to rotate about the rotation axis. The rotor can be used as a driver for the rotational movement of the nozzle. The rotor and the nozzle can be coupled to each other so that when the rotor rotates, the nozzle also rotates, in particular at the same angular velocity or rotation speed as the rotor. The rotor and the nozzle are particularly designed to rotate about the rotation axis.

[0010] The rotary press is suitable for wet cleaning with a cleaning liquid. The rotary press or cleaning device may include supply lines, pumps and / or appropriate wastewater structures.

[0011] This allows the injection opening to be moved using the (rotational) movement of the rotor. No separate drive is required for the (rotational) movement of the injection opening. As a result, the design effort for the cleaning device can be reduced. Due to the rotation of the injection opening, injection shadows can be avoided or at least reduced during the cleaning process. The cleaning process can be carried out optimally and the cleaning time can be reduced. This can reduce the costs of the rotary press (low design effort) and the costs of each cleaning process (due to the avoidance of injection shadows).

[0012] According to a further development of the rotary press, static nozzles can be arranged at the injection opening.

[0013] This allows the cleaning agent to be sprayed in a targeted manner using a simple method and to the desired measuring pressure. The spray pattern of the cleaning agent can be adjusted as required.

[0014] According to a further development of the rotary press, a rotary nozzle can be arranged on the ejection opening. The rotary nozzle can be spherical. The rotary nozzle can be designed to rotate (spin) during the cleaning process, thereby ejecting the cleaning agent around its own axis of rotation. The rotary movement of the rotary nozzle can be caused by the ejection of the cleaning agent (recoil principle) (similar to a dishwasher).

[0015] This allows the cleaning agent to be distributed more effectively over as many surfaces as possible. The cleaning agent spray pattern can be adjusted as required.

[0016] According to a further development of the rotary press, the cleaning device can comprise at least one internal supply channel, in particular a plurality of internal supply channels, for guiding the cleaning agent to the injection opening. The internal supply channel can be arranged at least partially, in particular completely, in the rotor. The internal supply channel can open into the injection opening.

[0017] In this way, the injection nozzles (or at least part of the cleaning device) can be integrated into the rotor. This eliminates the need for external components, such as supply lines for cleaning agents and static cleaning nozzles. These also have to be extensively cleaned after batch processing. By integrating the injection nozzles into the rotor (disc), additional cleaning work for these components can be eliminated. In other words, due to the integration of the injection nozzles (or cleaning technology) into the rotor, many cleaning nozzles and their supply lines, in particular static, externally arranged cleaning nozzles and their supply lines, can be omitted. This reduces cleaning time, enhances the clear layout of the machine and saves costs.

[0018] According to a further development of the rotary press, the cleaning device can comprise at least one external supply channel, in particular a plurality of external supply channels, for guiding the cleaning agent to the injection opening. The external supply channel can be arranged at least partially, in particular completely, outside the rotor. The external supply channel can lead to the injection opening.

[0019] This makes it possible to realize injection openings using rotor rotation by a simple method. No conversion and / or replacement of the rotor is necessary. For example, a rotary press can be "upgraded" without a rotor having an internal supply channel for guiding the cleaning agent.

[0020] According to other developments of the rotary press, the rotary press may include at least one upper tabletting punch. Alternatively or additionally, the rotary tablet press may include at least one lower tabletting punch. The upper and lower tabletting punches may be designed to cooperate in compressing powder, in particular to produce tablets. The upper tabletting punch and / or the lower tabletting punch may be designed as a tabletting tool or a stuffing punch. The cleaning device may include at least one cleaning punch. The cleaning punch may be designed to be interchangeable with the lower tabletting punch and / or the upper tabletting punch. At least one channel for guiding a cleaning agent to the injection port may be arranged in the cleaning punch. The channel may lead to the injection port.

[0021] This enables the cleaning agent to be sprayed in a targeted manner onto surfaces that are difficult or impossible to reach, such as in the area of ​​the guide curves of tableting punches or tampering punches. The cleaning process can thus be further optimized.

[0022] According to other developments of the rotary press, the cleaning device may include at least one guide element. The guide element may be tubular. The guide element may be designed as a tube. The guide element may be designed to be fixed (or fastened) to the rotor. The injection port may be arranged in or on the guide element. At least one guide channel for guiding the cleaning agent to the injection port may be arranged in the guide element. The guide channel may lead to the injection port.

[0023] This allows the injection opening to be moved radially outward using a simple method. Therefore, the arrangement of the injection opening (relative to the radial direction of the rotor) can be variably or purposefully adjusted. Therefore, the injection of the cleaning agent can be purposefully adjusted.

[0024] According to other developments of the rotary press, the cleaning device can include an inlet for introducing the cleaning agent into the rotor. The inlet can lead into the rotor in the area of ​​the axis of rotation. The inlet can be fluidically coupled to an internal supply channel, an external supply channel, a channel for a cleaning punch and / or a guide channel of a guide element. The inlet can be sealed using a sliding seal on the rotor. The inlet can be designed as a separate rotary joint.

[0025] The inner supply channel, the outer supply channel, the channel of the cleaning punch and / or the guide channel of the guide element can all be fluidically coupled to one another.

[0026] In the present context, fluid connection or fluid coupling means that a gas and / or a liquid (fluid) can flow between two fluidly coupled elements or between two fluidly connected elements.

[0027] This allows a simple method of directing the cleaning agent through the rotor to the injection opening.

[0028] According to a further development of the rotary press, the cleaning device can comprise a pump for pumping the cleaning agent into the injection opening.

[0029] This enables the cleaning agent to be delivered in a simple manner so that it can be sprayed through the spray opening.

[0030] This object is also achieved by a method for cleaning a rotary press, in particular a rotary tablet press, according to the above, having the features of the subclaims.

[0031] The method comprises the following steps:

[0032] The injection port is rotated about the rotation axis by rotating the rotor.

[0033] The cleaning agent is sprayed through spray ports and / or static nozzles and / or rotating nozzles.

[0034] With regard to the advantages that can be achieved thereby, reference is made to the statements in this respect regarding the rotary press. The measures relating to the rotary press and / or the following explanations can be used for further implementation of the method.

[0035] The method may include the following steps:

[0036] The cleaning agent is pumped into the circuit. The cleaning agent can be circulated (especially by means of a pump), i.e. can be used several times.

[0037] This means that the cleaning agent can be used multiple times, thus saving usage. This can reduce the cost of cleaning agents.

[0038] The method may include the following steps:

[0039] After the sprayed cleaning agent passes through the spray port and / or the static nozzle and / or the rotating nozzle once, the sprayed cleaning agent is collected and processed.

[0040] This means that the cleaning agent is only used once. This means that fresh and uncontaminated cleaning agent can always be used during the cleaning process. This improves the cleaning effect.

[0041] The method may include the following steps:

[0042] The cleaning agent is guided through the inner supply channel, the outer supply channel, the channel of the cleaning plunger and / or the guide channel of the guide element.

[0043] Therefore, the cleaning agent can be guided to the injection port by a simple method and injected through the injection port.

[0044] The method may include the following steps:

[0045] Closing the injection port and / or the internal supply channel. Closing can be achieved using the upper tabletting punch and / or the lower tabletting punch.

[0046] This allows to close or reopen the injection opening and / or the internal supply channel using simple (already existing) methods. This allows to control or adjust the injection of cleaning agent from the injection opening (the injection opening can be closed or opened) as required. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Further features, details and advantages of the invention can be gathered from the claims and the following description of exemplary embodiments with reference to the attached drawings. In the drawings:

[0048] Figure 1 is a perspective view of a rotary press having a rotor;

[0049] Figure 2 is based on Figure 1 A side view of a rotary press;

[0050] Figure 3 is a perspective view of a rotor of a rotary press according to a first exemplary embodiment;

[0051] Figure 4 is based on Figure 3 A cross-sectional view of the rotor;

[0052] Figure 5 Shows Figure 4 Details of the cross-section in the;

[0053] Figure 6 is a cross-sectional view of a rotor according to a second exemplary embodiment;

[0054] Figure 7 shows a detail of a perspective view of a rotor according to a third exemplary embodiment; and

[0055] Figure 8 Shown according to Figure 7 Detail of a cross-section of the rotor.

[0056] In the following description and drawings, corresponding components and elements have the same reference numerals. For the sake of clarity, not all reference numerals are shown in all figures. DETAILED DESCRIPTION

[0057] Figure 1 and Figure 2 A perspective view and a side view are shown of a rotary press 10 with a rotor 14. In the present example, the rotary press 10 is designed as a rotary tablet press.

[0058] Figure 3 shows a perspective view of the rotor 14 of the rotary press 10 according to the first exemplary embodiment, Figure 4 A cross-sectional view thereof is shown.

[0059] The rotor 14 is designed to be rotatable about the rotation axis 12. In the present example, the rotor 14 comprises a plurality of upper tabletting punches 30 and a plurality of lower tabletting punches 31. The upper tabletting punches and / or the lower tabletting punches 30, 31 may be designed as tamper punches.

[0060] The rotor 14 comprises a cleaning device 16 for cleaning the rotary press 10. The cleaning device 16 comprises at least one injection opening 18 for injecting a cleaning agent 20. In this example, the cleaning device 16 comprises a plurality of injection openings 18.

[0061] In the present case, the cleaning device 16 is coupled to the rotor 14 and is configured to rotate the injection openings 18 about the rotation axis 12 by the rotation of the rotor 14. Thus, the cleaning device 16 and in particular the injection openings 18 can rotate together with the rotor 14. The cleaning device 16 is in particular integrated in the rotor 14.

[0062] In this example, the cleaning device 16 comprises a lower internal supply channel 26, a middle internal supply channel 27 and an upper internal supply channel 29 for guiding the cleaning agent 20 to the corresponding injection openings 18. In this example, the three internal supply channels 26, 27, 29 are arranged one above the other with respect to the direction of gravity 15.

[0063] In the present case, the internal supply channels 26, 27, 29 are arranged completely within the rotor 14. The internal supply channels 26, 27, 29 are fluidically connected to the corresponding injection openings 18, respectively.

[0064] In the present case, the internal supply channels 26, 27, 29 are each formed as a hole in the rotor 14. In the present case, the internal supply channels 26, 27, 29 designed as holes are oriented perpendicularly to the rotation axis 12, i.e. they extend along a horizontal straight line (perpendicularly to the direction of gravity 15). The direction of gravity 15 is determined by Figures 4 to 8 It is also conceivable that the internal supply channels 26, 27, 28, which are designed as holes in this example, have a slight slope, ie are inclined to the horizontal direction. This allows the internal supply channels 26, 27, 28 to be automatically emptied after the cleaning process.

[0065] In this example, the cleaning device 16 has an inlet 40 for introducing the cleaning agent 20 into the rotor 14. The inlet 40 is only schematically indicated by a large arrow (in Figure 4 and 6 In this case, the inlet 40 is arranged in the region of the axis of rotation 12. The inlet 40 thus opens centrally into the rotor 14. Figure 4 and 6 As shown, the inlet 40 can open into the rotor 14 from below relative to the direction of gravity 15 . It is also conceivable that the inlet 40 can open into the rotor 14 from above relative to the direction of gravity 15 .

[0066] In this example, the cleaning device 16 comprises a pump 42 for pumping the cleaning agent 20. The pump is only schematically represented (in Figure 4 and 6 The cleaning agent 20 is delivered to the rotor 14 through the inlet 40 by a pump 42. In the rotor 14, the cleaning agent 20 pumped in through the inlet 40 is transferred to the corresponding injection openings 18 by means of the internal supply channels 26, 27, 29.

[0067] The internal supply channels 26, 27, 29 can be Figure 4 The right end of the inner supply channel 26, 27, 29 leads to the inlet 40. The inner supply channels 26, 27, 29 can be designed at least partially as a common channel. A chamber 41 can be arranged between the inner supply channels 26, 27, 29 and the inlet 40, which can fluidically connect the inner supply channels 26, 27, 29 and the inlet 40. The chamber 41 can be used as a cleaning agent reservoir or buffer.

[0068] In this example, the lower internal supply channel 26 is Figure 4The left end of the lower inner supply channel 26 leads to the injection opening 18, which is blocked or closed by the lower tablet punch 31. This allows the lower tablet punch 31 to be included in the cleaning process. In this case, the lower internal supply channel 26 and the corresponding injection opening 18 can be closed and opened again by moving the corresponding lower tablet punch 31 in the direction of gravity 15.

[0069] In this example, the cleaning device 16 includes at least one guide element 36. In this example, the guide element 36 is designed in the form of a straight tube. The guide element 36 can be fixed to the rotor 14 (such as Figure 4 The injection port 18 is arranged at one end of the guide element 36. Figure 4 In this example, a guide channel 38 for guiding the cleaning agent 20 to the injection port 18 is arranged in the guide element 36. The guide channel 38 is on the one hand (with its Figure 4 The left end in the middle) leads to the corresponding injection port 18, and on the other hand (with its Figure 4 The right end in the middle) leads to the middle internal supply channel 27.

[0070] In this example, the static nozzle 22 is arranged on the injection opening 18, and the injection opening 18 is arranged on the guide element 36. It is also conceivable that the rotating nozzle 24 (see Figure 7 and Figure 8 ) or another nozzle may be arranged on the injection port 18. The nozzle may be selected so as to adjust the injection manner (injection angle, injection direction, injection speed, injection pattern, etc.) of the cleaning agent 20 as required.

[0071] In this example, the cleaning device 16 includes at least one cleaning punch 32. The cleaning punch 32 is designed to be interchangeable with the upper tabletting punch 30. Therefore, the cleaning punch 32 can be arranged on the rotor 14 or fixed on the rotor 14 to replace the upper tabletting punch 30. In this example, the cleaning punch 32 is replaced by the upper tabletting punch 30 and arranged on the rotor 14.

[0072] Figure 5 Shown according to Figure 4 Detail of a sectional view of FIG. 1 , in which the cleaning punch 32 is shown in enlarged form.

[0073] In this example, the cleaning punch 32 has four injection ports 18 for spraying the cleaning agent 20. The four injection ports 18 are arranged on the cleaning punch 32. In this example, four channels 34 are formed in the cleaning punch 32 for guiding the cleaning agent 20 to the corresponding injection ports 18 arranged on the cleaning punch 32. On the one hand, the four channels 34 lead to the corresponding injection ports 18 respectively. On the other hand, the four channels 34 converge and lead to the upper internal supply channel 29 of the rotor 14. The cleaning agent 20 can be sprayed through the cleaning punch 32, especially in the area of ​​the guide curve 35 of the upper tableting punch 30.

[0074] Figure 6 A cross-sectional view of a rotor 14 according to a second exemplary embodiment is shown. Figures 3 to 5 The differences of the first exemplary embodiment shown in FIG. 1 are as follows:

[0075] In the present case, the cleaning device 16 additionally has at least one external supply channel 28 for conducting the cleaning agent 20 to the injection opening 18 . In the present case, the external supply channel 28 is arranged at least partially outside the rotor 14 .

[0076] The external supply channel 28 leads to the chamber 41 and / or the inlet 40 on the one hand and to the corresponding injection opening 18 on the other hand. In this example, the spherical rotating nozzle 24 is arranged on the injection opening 18 to which the external supply channel 28 leads. With the help of the rotating nozzle 24, the cleaning agent 20 can be sprayed in as many spatial directions as possible.

[0077] The external supply channel 28, the injection port 18 arranged on the supply channel 28 and the rotating nozzle 24 arranged on the injection port 18 are only schematically shown (see FIG. Figure 6 middle).

[0078] Figure 7 shows a detail of the perspective view, Figure 8 A detail of a sectional view of a rotor 14 according to a third exemplary embodiment is shown. The third exemplary embodiment differs from the first and / or second exemplary embodiment as follows:

[0079] Instead of the static nozzle 22, a spherical rotating nozzle 24 is arranged on the spray opening 18 arranged on the guide element 36. The cleaning agent 20 can be sprayed in as many spatial directions as possible by means of the spherical rotating nozzle 24.

[0080] Reference below Figures 1 to 8 The method of cleaning the rotary press 10 is described below:

[0081] The method comprises the following steps:

[0082] The injection openings 18 are rotated about the rotation axis 12 by rotating the rotor 14. Since the injection openings 18 are integrated in the rotor 14 and / or coupled to the rotor 14, they rotate together with the rotor 14.

[0083] The cleaning agent 20 is sprayed through the spray port 18 and / or the static nozzle 22 and / or the rotating nozzle 24 .

[0084] In this example, the method includes the following steps:

[0085] The cleaning agent 20 is pumped into the circuit. To this end, the cleaning agent 20 can be pumped in a circuit through the rotor 14 and / or the cleaning device 16 by means of a pump 42. Thus, the cleaning agent 20 can be reused several times.

[0086] Alternatively, the method may include the following steps:

[0087] After the cleaning agent 20 is sprayed once through the spray port 18 and / or the static nozzle 22 and / or the rotating nozzle 24, the sprayed spray agent 20 is collected and processed. After the cleaning agent 20 is sprayed once, it can be collected in a collection container (not shown).

[0088] In this example, the method includes the following steps:

[0089] The cleaning agent 20 is guided through the internal supply channels 26, 27, 29, the external supply channel 28, the channel 34 of the cleaning punch 32 and / or the guide channel 38 of the guide element 36. In this way, all channels and / or injection openings 18, in particular those channels and / or injection openings 18 that are fluidically connected to one another, are acted upon or supplied with cleaning agent 20.

[0090] In this example, the method includes the following steps:

[0091] Closing the spray openings 18 and / or the lower internal supply channel 26. This can be achieved, for example, by means of the lower tabletting punch 31. By moving the lower tabletting punch 31 in the direction of gravity 15, the lower internal supply channel 26 or the spray openings 18 arranged on the lower internal supply channel 26 can be closed or opened again. This allows the spray pattern of the cleaning agent 20 to be influenced and adjusted as desired.

Claims

1. A rotary press (10), in particular a rotary tablet press, comprising: - a rotor (14) rotatable about an axis of rotation (12), and - A cleaning device (16) for cleaning the rotary press (10), wherein the cleaning device (16) comprises at least one injection opening (18), in particular a plurality of injection openings (18), for injecting a cleaning agent (20), characterized in that the cleaning device (16) is coupled to the rotor (14) and is configured such that the injection opening (18) can be rotated about the rotation axis (12) by the rotation of the rotor (14).

2. The rotary press (10) according to claim 1, characterized in that A static nozzle (22) is arranged on the injection port (18).

3. The rotary press (10) according to claim 1, characterized in that: A rotating nozzle (24), in particular a spherical rotating nozzle (24), is arranged on the injection port (18).

4. A rotary press (10) according to any one of the preceding claims, characterised in that The cleaning device (16) comprises at least one internal supply channel (26, 27, 29) for conducting a cleaning agent (20) to the injection opening (18), wherein the internal supply channel (26, 27, 29) is at least partially, in particular completely, arranged inside the rotor (14), in particular the internal supply channel (26, 27, 29) opens into the injection opening (18).

5. A rotary press (10) according to the preceding claim, characterised in that The internal supply channels (26, 27, 29) are at least partially, in particular completely, formed as holes in the rotor (14).

6. A rotary press (10) according to any one of the preceding claims, characterised in that The cleaning device (16) comprises at least one external supply channel (28) for conducting cleaning agent (20) to the injection opening (18), wherein the external supply channel (28) is arranged at least partially, in particular completely, outside the rotor (14), in particular, the external supply channel (28) opens into the injection opening (18).

7. A rotary press (10) according to any one of the preceding claims, characterised in that The rotary press (10) comprises at least one upper tabletting punch (30) and / or at least one lower tabletting punch (31), in particular a stuffing punch, the cleaning device (16) comprises at least one cleaning punch (32), wherein the cleaning punch (32) is designed to be interchangeable with the lower tabletting punch (31) and / or the upper tabletting punch (30), the injection port (18) is arranged in or on the cleaning punch (32), and at least one channel (34) for guiding the cleaning agent (20) to the injection port (18) is arranged in the cleaning punch (32), in particular, the channel (34) leads to the injection port (18).

8. A rotary press (10) according to any one of the preceding claims, characterised in that The cleaning device (16) comprises at least one guide element (36), in particular a tubular guide element (36), wherein the guide element (36) is designed to be fixed to the rotor (14), the injection port (18) is arranged in or on the guide element (36), and at least one guide channel (38) is arranged in the guide element (36) for guiding the cleaning agent (20) to the injection port (18), in particular, the guide channel (38) opens into the injection port (18).

9. A rotary press (10) according to any one of the preceding claims, characterised in that The cleaning device (16) comprises an inlet (40) for introducing a cleaning agent (20) into the rotor (14), in particular the inlet (40) opens into the rotor (14) in the region of the rotation axis (12).

10. A rotary press (10) according to any one of the preceding claims, characterised in that The cleaning device (16) comprises a pump (42) for pumping a cleaning agent (20), in particular for pumping the cleaning agent (20) through the cleaning device (16) and / or the spray opening (18).

11. A method for cleaning a rotary press (10), in particular a rotary tablet press, according to any one of the preceding claims, comprising the following steps: - rotating the rotor (14) so ​​that the injection port (18) rotates about the rotation axis (12); - Spraying the cleaning agent (20) through the spray opening (18) and / or through the static nozzles (22) and / or through the rotating nozzles (24).

12. The method according to claim 11, characterized in that The method further comprises the following steps: - Pump cleaning agent (20) into the circuit.

13. The method according to claim 11, characterized in that The method further comprises the following steps: After the sprayed cleaning agent (20) passes through the spray opening (18) and / or through the static nozzle (22) and / or through the rotating nozzle (24) once, the sprayed cleaning agent (20) is collected and processed.

14. The method according to any one of claims 11 to 13, characterized in that The method further comprises the following steps: - guiding the cleaning agent (20) through the inner supply channels (26, 27, 29), the outer supply channel (28), the channel (34) of the cleaning punch (32) and / or the guide channel (38) of the guide element (36).

15. The method according to any one of claims 11 to 14, characterized in that The method further comprises the following steps: - Closing the injection opening (18) and / or the internal supply channel (26, 27, 29), in particular by means of an upper tabletting punch (30) and / or a lower tabletting punch (31).

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