Rotary tablet press and method for lubricating pressing punches using rotary tablet press

Abstract

To provide a rotary tablet press.SOLUTION: There is provided a rotary tablet press, comprising a lubrication device configured to lubricate, with a lubricant, upper press punches and / or lower pressing punches. The lubrication device includes a lubricant reservoir; and a stationary applicator connected to the lubricant reservoir and configured to apply the lubricant to the upper press punches and / or the lower pressing punches rotating, with a rotor, past the applicator. The lubrication device comprises a control apparatus designed to individually control, for different upper and / or lower pressing punches, an amount of lubricant applied by the applicator to the upper press punch and / or the lower pressing punch.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rotary tablet press comprising a rotor rotatable by a rotary drive, the rotor having upper punch guides for upper press punches and lower punch guides for lower press punches, and a die plate arranged between the punch guides, the press punches cooperating with cavities in the die plate, the rotary tablet press further comprising a filling device for filling the cavities in the die plate with powder material, the rotary tablet press comprising a press device having upper and lower press units cooperating with the upper and lower press punches for compressing the powder material in the cavities in the die plate into tablets during operation, the rotary tablet press having an ejection device for ejecting tablets, and the rotary tablet press further comprising a lubrication device for lubricating the upper and / or lower press punches with a lubricant. The present invention also relates to a method of lubricating the upper and / or lower press punches using a rotary tablet press. [Background technology]

[0002] A rotary tablet press is typically equipped with a number of upper and lower press punches, each pair of which is assigned to one cavity of the die plate. During operation, the upper and lower press punches rotate together with the die plate, their axial movement controlled by a control cam and guided by upper and lower punch guides. While rotating, the die plate passes through separate devices of the rotary tablet press: a filling device for filling the die plate cavities with powder material to be compressed, and a pressing device for forcing the upper and lower press punches into the cavities by upper and lower press units, e.g., press rollers, to compress the powder material into tablets. After passing through the pressing device, the upper press punch is guided upward and out of the cavity, and the tablet formed in the cavity is pushed up and over the die plate by the lower press punch. For example, a scraper scrapes the tablet off the die plate and out of the rotary tablet press, from where it is fed for further processing.

[0003] The press punches of such rotary tablet presses must be periodically lubricated with a lubricant to prevent them from becoming stiff, particularly in the punch guides. Typically, the lubricant is supplied to the press punches via injection elements and lubrication pumps. Lubricating felts can also be used. It is also known to introduce dry lubricant into the die plate cavities, particularly to ensure smooth entry of the press punches into the cavities and to prevent adhesion of the powder material.

[0004] Patent Document 1 discloses a spray device for the lower punch of a tablet press for lubricating the die. The spray device is directed toward the die of the die plate so that the nozzle opening of the quick-action valve is aligned with the side wall of the lower punch when it is in its lowest position. When the lower punch is inserted into the die, only its side wall should be lubricated with lubricant using a cycle-controlled and micro-supply method. The quick valve is connected via electrical wiring to a control unit that determines the cycle frequency and lubricant supply amount according to the rotor rotation speed. The amount of oil per pulse can be set by electrically adjusting the valve via the valve input. This device lubricates the die of the die plate. The purpose of this method is to optimize product release from the die wall. Therefore, tablets formed in the die are less likely to adhere to the lubricant and are easier to release.

[0005] The conventional lubrication devices described above require a large amount of lubricant. The lubricant often does not completely reach the press punches. Some of the lubricant passes through the press punches and splashes into the interior of the rotary tablet press, ultimately adhering to the formed tablets. When lubricating felts are used, the felts can become contaminated and lose their functionality. Furthermore, conventional lubricant supply tubes are installed inside the rotor, and the lubricant must be distributed within the tubes to reach the press punches. If these tubes become clogged, the lubricant cannot be distributed evenly. Cleaning the tubes is time-consuming. Furthermore, the lubricant is unevenly distributed among the tubes. As a result, the lubricant supply to the press punches varies. At the start of tablet production, the tubes must first be filled with lubricant before it reaches the press punches.

[0006] The device described in Patent Document 1 also cannot adapt to the different lubrication requirements of the individual press punches of a rotary tablet press. The amount of oil delivered via the valve can be adjusted between different production steps or different configurations of the tablet press. However, it cannot detect or respond to changes in the lubrication requirements that occur during the production process, especially for the press punches. Furthermore, to optimize product removal, only the die is lubricated. There is no lubrication of the punch shaft or punch head. Instead, the press punches are lubricated only at the neck below the press surface. This does not prevent increased wear on the punches, especially the punch shaft. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] German Utility Model No. 20107072 Summary of the Invention [Problem to be solved by the invention]

[0008] In light of the above-mentioned prior art, it is an object of the present invention to provide a rotary tablet press and a method of the type mentioned at the beginning, which allows for a precise and economical supply of lubricant and also accommodates the different lubrication requirements of the individual press punches, in particular in such a way that wear on the press punches can be effectively prevented. [Means for solving the problem]

[0009] This object is achieved by the independent claims 1 and 14. Advantageous embodiments are described in the dependent claims, the description and the drawings.

[0010] The invention achieves this object in relation to a rotary tablet press of the kind mentioned at the outset in that the lubricating device comprises a lubricant reservoir and a stationary applicator connected to the lubricant reservoir for applying lubricant to the upper and / or lower press punches which rotate together with the rotor past the applicator, and in that the lubricating device comprises a control device designed to enable the amount of lubricant applied by the applicator to the upper and / or lower press punches to be controlled individually for each of the different upper and / or lower press punches.

[0011] The basic configuration of the rotary tablet press was described at the beginning as the subject matter of the present invention. Reference is made to this. The tablets produced by the rotary tablet press may be pharmaceutical tablets. However, other tablets, such as dishwashing tablets, are also conceivable. According to the present invention, the lubrication device of the rotary tablet press comprises a lubricant reservoir and a stationary applicator connected to the lubricant reservoir for applying lubricant to the press punches that rotate together with the rotor past the applicator. The applicator is stationary and does not rotate together with the rotor of the rotary tablet press. The lubricant reservoir is also preferably stationary and, like the applicator, does not rotate together with the rotor. The lubricating device further comprises a control device, which is designed to control the applicator in such a way that the amount of lubricant applied by the applicator to the upper and / or lower press punches is individually controlled for each of the different upper and / or lower press punches.

[0012] Therefore, in the present invention, the lubricant is first applied directly to the press punch, particularly the punch shaft and punch head. This reduces the amount of lubricant required and ensures that the lubricant is supplied to the parts to be lubricated, effectively preventing wear on the press punch, especially when the press punch is guided through the punch guide. The control device for the lubricating device may be the same as the control device that controls the operation of the rotary tablet press, i.e., the machine control device, or it may be a control device designed independently of the machine control device. Rotary tablet presses typically have a press chamber in which a rotor is located. This press chamber is typically isolated from the outside by a housing. The lubricating device may also be located within the press chamber or the housing. The applicator is used to intermittently apply lubricant to the press punch as it moves past the applicator. The applicator can simultaneously apply lubricant to multiple press punches rotating past the applicator. Multiple applicators may also be arranged along a pitch circle formed by the press punches, and the multiple applicators apply lubricant to the passing press punches simultaneously or with a time lag. The applicator can also sequentially apply lubricant to multiple press punches rotating past the applicator. As part of the individual control of the amount of lubricant applied according to the present invention, it is also possible to not apply lubricant to individual press punches if no lubricant is particularly required.

[0013] The present invention thus reduces lubricant consumption compared to the prior art and prevents lubricant from spreading within the press chamber of a rotary tablet press, thereby minimizing the risk of lubricant contamination of the produced tablets. At the same time, the present invention allows for individual lubrication of press punches, particularly punch shafts and / or control cams guided in the associated punch guides and punch heads cooperating with, for example, press rollers, so that individual press punches can be lubricated more or less than other press punches during the production process. This allows for flexible and precise adaptation to different lubricant requirements, even during the production process. It is possible to prevent over-lubrication of press punches that are already sufficiently lubricated, while at the same time reliably preventing individual press punches from becoming under-lubricated, which could, for example, impede their operation in the punch guides and / or in the cavities of the die plate and increase wear. Long supply pipes in the press chamber, especially in the rotor of a rotary tablet press, are prone to clogging, require a great deal of cleaning effort, and can lead to uneven distribution of lubricant, which can be prevented by the present invention, in particular by an applicator that is arranged in a fixed position relative to the rotor and is connectable to a lubricant reservoir, for example, arranged in spatial proximity to the applicator. In particular, for example, all lower press punches can be lubricated by just one applicator. Similarly, upper press punches can be lubricated, if necessary. Of course, multiple applicators for lubricating the lower and / or upper press punches may also be provided. The lubricant reservoir may be arranged in spatial proximity to the applicator, as described above. The lubricant reservoir may be arranged, for example, in the drive chamber of the rotary press.

[0014] In a particularly practical embodiment, the applicator may comprise at least one valve that applies lubricant from a lubricant reservoir to the outer surfaces of the upper and / or lower press punches, in particular the punch shafts and / or punch heads. Multiple valves can be employed within one applicator, and they can simultaneously lubricate more than one press punch from the outside. Such valves allow for sufficiently precise application of lubricant, preferably in the form of droplets, even when there is a distance between the valve and the associated press punch. Meanwhile, particularly fast-acting valves can be used to lubricate each upper and / or lower press punch within exactly one rotation of the rotor, even when the rotor is moving at high speed.

[0015] The at least one valve may be arranged in an internal space, particularly an internal space of the rotor, radially arranged within the pitch circle described by the upper and / or lower press punches. The at least one valve applies lubricant to the upper and / or lower press punches from the inside to the outside. In this way, the lubricant flows around the outer periphery of the press punches due to centrifugal force, allowing the entire press punch to be lubricated with lubricant. The use of an applicator with at least one valve allows for a sufficiently compact design, since the at least one valve is arranged in the internal space of the rotor. In principle, the lubricant reservoir may be arranged within the internal space. This allows for a particularly short connection between the at least one valve and the lubricant reservoir. However, the lubricant reservoir may also be arranged separately. The at least one valve may also be arranged outside the pitch circle described by the upper and / or lower press punches. In this case, the at least one valve applies lubricant to the upper and / or lower press punches from the outside to the inside.

[0016] According to further embodiments, at least one valve can be arranged to lubricate the upper and / or lower press punch from above, below, and / or from the side. This is particularly true when multiple valves are used. Each valve can be controlled separately, for example, to lubricate only the punch shaft or punch head. These designs allow for particularly comprehensive lubrication of the press punches.

[0017] According to a further embodiment, at least one valve may be designed to apply lubricant intermittently at a frequency greater than 30 Hz, preferably greater than 100 Hz, more preferably greater than 200 Hz, and even more preferably less than 250 Hz. Using such a valve operable at a high frequency allows lubricant to be supplied to all upper or lower press punches during one rotor revolution, as previously described. This also applies to typical rotor rotation speeds of modern rotary tablet presses. For example, in the case of a rotor with 115 press punches and a rotor speed of 120 revolutions per minute, this corresponds to a valve operating frequency of 230 Hz. However, as previously described, it is also possible to apply lubricant to each press punch within multiple rotor revolutions, in which case, for example, a lower operating frequency can be set.

[0018] According to a further embodiment, the control device can be designed to control the applicator by taking into account the rotor rotational position and / or the delay time of the applicator or applicator valve and / or the flight time of the lubricant from the applicator or applicator valve to the upper and / or lower press punch. These parameters are crucial for determining when to open the applicator or valve for lubricant discharge in order to fully lubricate each desired press punch. In particular, the flight time of the lubricant from the valve or applicator outlet to the press punch, especially the flight time through the air gap between them, and any delay time after valve activation must be taken into account. A rotary encoder, typically provided in rotary tablet presses, ensures that the rotational position of the rotor and, therefore, the rotational position of the press punch are accurately known at all times. Based on the known rotor speed and the total delay resulting from the flight time and valve delay, it is possible to determine the rotor rotational position at which the applicator or valve should open in order to supply the associated press punch with the desired amount of lubricant. This allows a defined amount of lubricant to be supplied to each specific press punch. By controlling the applicator or valve with a controller, the required amount of lubricant can be applied individually to each particular press punch involved.

[0019] According to a further embodiment, the control device can take into account the lubricant pressure, lubricant temperature, lubricant viscosity, applicator or applicator valve opening time, applicator or applicator valve outlet geometry, and / or the distance from the applicator or applicator valve to the upper and / or lower press punches to determine the lubricant flight time. The lubricant flight time from the applicator or valve to the press punches depends on various parameters, in particular the lubricant pressure, applicator / valve opening time, lubricant temperature and viscosity, applicator or valve outlet geometry, and the distance from the applicator or valve to the press punches. To determine the lubricant's, e.g., lubricant drop, injection speed, tests are performed in advance using the aforementioned parameters. For example, if the press punches of a rotary tablet press are changed between various production runs, the distance between the applicator and the press punches may change. These differences can be taken into account accordingly when calculating the flight time.

[0020] The lubricant reservoir may further include a press device that maintains the lubricant at a predetermined pressure within the lubricant reservoir. To achieve reliable lubrication based on the above calculations and parameters, it is desirable to maintain the lubricant pressure as constant as possible. The press device may include, for example, a lubricant pump or a cartridge with a pressure regulator. However, a non-pressurized system is also possible, in which case a press device is not required.

[0021] According to a further embodiment, the control device is designed to individually control the amount of lubricant applied by the applicator to the upper and / or lower press punches, in particular the size or number of drops or the interval between lubricant applications, and can be designed to be individually controlled for different upper and / or lower press punches by adjusting the size of the drops of lubricant applied by the applicator or valve and / or the discharge time of the applicator or valve and / or the number of lubricant applications applied by the applicator or valve for each individual upper and / or lower press punch. Using the aforementioned parameters, the amount of lubricant applied individually can be reliably and accurately controlled.

[0022] According to a further embodiment, the control device can receive measurements from at least one sensor of the rotary tablet press, and the control device can be designed to individually control the amount of lubricant applied by the applicator to different upper and / or lower press punches based on the received measurements. The at least one sensor can include at least one stiffness sensor, which can individually measure the stiffness of each upper and / or lower press punch, particularly within the upper or lower punch guide. Such stiffness measurements can determine which press punches are stiffer than the other press punches, particularly during movement within the upper or lower punch guide and / or cavity. If an increase in stiffness of individual press punches is detected, these press punches can be individually supplied with more lubricant than the other press punches. The supply of lubricant can also be stopped for particularly smooth-running press punches, thereby further saving lubricant. For example, a force sensor can be used as a stiffness sensor, which records as a measurement the stiffness of the press punch during its axial movement, particularly the force required for the press punch to move within the associated punch guide. Multiple stiffness sensors can also be provided. The stiffness sensor can measure the stiffness of each press punch individually.

[0023] According to a further embodiment, the lubricant reservoir may contain a liquid lubricant, in particular a lubricating oil, and the applicator may intermittently apply the liquid lubricant to the upper and / or lower press punches by dripping and / or by atomizing a predetermined amount of the liquid lubricant and applying it to the upper and / or lower press punches. In either case, this allows the lubricant to be separated and applied specifically to each press punch. In the case of a spray, in particular, a predetermined amount of atomized lubricant is intermittently sprayed and applied to the upper and / or lower press punches.

[0024] According to a further embodiment, the lubrication device may comprise a heating device for heating the applicator, thereby achieving a desired lubricant viscosity to precisely achieve optimum lubrication.

[0025] The present invention also solves the problem by a method for lubricating the upper and / or lower press punches using a rotary tablet press according to the invention, which is suitable and designed to carry out the method appropriately, in particular with respect to the lubrication device and the control device.

[0026] An exemplary embodiment of the invention is explained in more detail below with the aid of a schematic diagram. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a rotary tablet press according to the present invention, showing an exploded view of the rotor. [Figure 2] FIG. 1 is a diagram of a lubrication system for a rotary tablet press according to the present invention, illustrating the upper press punch. [Figure 3] 1 is a cross-sectional view showing a portion of a rotary tablet press according to the present invention.

[0028] Unless otherwise specified, like reference numbers refer to like objects in the figures. DETAILED DESCRIPTION OF THE INVENTION

[0029] In the rotary tablet press shown in FIG. 1, powder material is compressed into tablets. The rotary tablet press comprises a rotor rotated by a rotary drive in a press chamber 11. The rotor is provided with a die plate 10 having a plurality of cavities 12. The cavities 12 are formed, for example, by holes in the die plate 10. The rotor further comprises a plurality of upper and lower press punches 14 and 16, which rotate synchronously with the die plate 10. The upper press punch 14 is axially guided in an upper punch guide 18, and the lower press punch 16 is axially guided in a lower punch guide 20. The axial movement of the upper and lower press punches 14 and 16 during rotor rotation is controlled by an upper control cam element 22 and a lower control cam element 24. The rotary tablet press further comprises a filling device 26, which has a filling reservoir 28 and a filling chamber 30, which are connected via a filling pipe 32. Thus, in this embodiment, the powder material moves by gravity from the filling reservoir 28 through the filling tube 32 into the filling chamber 30, and from there is supplied, also by gravity, to the cavity 12 of the die plate 10 through a filling opening provided on the underside of the filling chamber 30.

[0030] The rotary tablet press further comprises a press unit 34. The press unit 34 comprises a pre-press unit having an upper pre-press roller 36 and a lower pre-press roller 38, and a main press unit having an upper press roller 40 and a lower press roller 42. The rotary tablet press further comprises a discharge unit 44 and a scraper unit 46, the latter having a scraping element that feeds tablets 48 produced by the rotary tablet press to a discharge unit 50 for ejection from the rotary tablet press. The scraper unit 46 may, for example, comprise a preferably crescent-shaped scraper element that, in the region of the discharge unit 44, scrapes tablets 48 delivered to the upper surface of the die plate 10 by the lower press punch 16 from the die plate 10 and feeds them to the discharge unit 50. The rotary tablet press also comprises a control unit 52, in particular a machine control unit 52, for controlling the operation of the rotary tablet press and for controlling the lubrication unit of the present invention, as will be explained in more detail below.

[0031] FIG. 2 shows a lubricating device, used as an example for lubricating the upper press punch 14 in the rotary tablet press of FIG. 1 . The lubricating device includes a lubricant reservoir 54, which contains, for example, a liquid lubricant, i.e., lubricating oil. The lubricant in the lubricant reservoir 54 can be maintained at a predetermined, particularly constant, pressure by a press device (not shown). In the illustrated example, the applicator of the lubricating device includes three valves 56, 58, and 60, which are connected to the lubricant reservoir 54 via short connecting lines 62, 64, and 66, respectively. Both the lubricant reservoir 54 and the valves 56, 58, and 60, including the connecting lines 62, 64, and 66, may be located within an internal space 68, preferably located within the rotor or the rotary tablet press, and do not rotate with the rotor of the rotary tablet press. However, it is also possible, for example, to locate the lubricant reservoir 54 outside the internal space 68 and supply lubricant from the lubricant reservoir 54 to the valves 56, 58, and 60 via connecting lines through the internal space 68. Each valve 56, 58, 60 has a discharge port 70, 72, 74, specifically, a discharge nozzle 70, 72, 74. In this embodiment, the discharge ports 70, 72, 74 are directed toward different regions of the outer surface of the upper press punch 14. Specifically, the valve 56 having the discharge port 70 is directed toward the upper side of the punch head, while the valves 58, 60 having the discharge ports 72, 74 are directed at different heights toward the punch shaft of the upper press punch 14. The discharge ports 70, 72, 74 are each spaced apart from the upper press punch 14. During operation of the rotary tablet press, lubricant is supplied from the lubricant reservoir 54 onto the outer surface of the upper press punch 14 through the discharge ports 70, 72, 74, which are controlled by the control device 52. Figure 2 illustrates three valves 56, 58, 60 arranged within the interior space 68. It is possible for the lubricating device to have, for example, only one or two of the illustrated valves 56, 58, 60. Alternatively or additionally, the lubrication device may have further valves that allow lubrication of other areas outside the upper press punch 14. As mentioned above, the lubrication device has been described using the example of lubricating the upper press punch 14. The lubrication device for the lower press punch 16 may be designed similarly.During operation, the upper press punches 14 rotate past a fixed lubrication system as the rotor rotates. Figure 3 shows an example of this configuration, with the upper punch guide 18 viewed from above. The punch guide 18 has punch guide holes 76, and the upper press punches 14 are axially guided within the punch guide holes 76 by their punch shafts. Only the valves 58 are shown in Figure 3 as an illustrative example.

[0032] The rotary tablet press further includes a number of sensors that measure various parameters during operation, such as the press force and / or the stiffness of the press punches 14, 16 within the punch guides 18, 20. The sensor measurements are available to the control device 52. The control device controls the lubrication device, particularly the applicators of the valves 56, 58, 60 for individually lubricating the upper press punches 14, based on, for example, the stiffness sensor measurements. If, for example, the stiffness sensor detects that an individual upper press punch 14 is stiff, the valves 56, 58, 60 are controlled by the control device 52 to appropriately lubricate those upper press punches 14 with a large amount of lubricant. For example, the size of the lubricant droplets applied can be adjusted for this purpose. The amount of misted lubricant can also be adjusted. Furthermore, the duration of lubricant application and / or the number of spurts of lubricant applied can also be adjusted. It is also envisioned that the valves 56, 58, 60 can be individually controlled by the control device 52, for example, to appropriately apply more or less lubricant to specific areas of the press punch 14.

[0033] The valves 56, 58, and 60 may be designed to apply lubricant intermittently at a frequency of 30 Hz or more, preferably 100 Hz or more, more preferably 200 Hz or more, and even more preferably 250 Hz or less, so that even when there are many upper press punches 14 and the rotor is rotating at high speed, lubricant can be supplied to all of the upper press punches 14 during one rotation of the rotor.

[0034] To precisely deliver a predetermined amount of lubricant to a particular upper press punch 14, the applicator or control device for controlling the valves 56, 58, 60 takes into account the rotational position of the rotor and / or the delay time of the valves 56, 58, 60 and / or the flight time of the lubricant from the valves 56, 58, 60 to the upper press punch 14, as previously described. [Explanation of symbols]

[0035] 10 Die Plate 12 cavities 14 Upper press punch 16 Lower press punch 18 Upper punch guide 20 Lower punch guide 22 Upper control cam element 24 Lower control cam element 26 Filling equipment 28 Filling reservoir 30 Filling chamber 32 Filling tube 34 Press equipment 36 Upper spare press roller 38 Lower spare press roller 40 Upper press roller 42 Lower press roller 44 Discharge device 46 scraping device 48 tablets 50 Ejector 52 Control device 54 Lubricant reservoir 56, 58, 60 valves 62, 64, 66 connection lines 68 Interior Space 70,72,74 Discharge port 76 Punch guide hole

Claims

1. 1. A rotary tablet press comprising a rotor rotatable by a rotary drive, The rotor has an upper punch guide (18) for an upper press punch (14), a lower punch guide (20) for a lower press punch (16), and a die plate (10) arranged between the punch guides; The press punches (14, 16) cooperate with the cavities (12) of the die plate (10); The rotary tablet press further comprises a filling device (26) for filling the powder material to be compressed into the cavities (12) of the die plate (10); the rotary tablet press comprises a press device (34) having an upper press unit (40) and a lower press unit (42) which cooperate with the upper press punch (14) and the lower press punch (16) during operation to compress the powder material in the cavities (12) of the die plate (10) into tablets (48); The rotary tablet press has an ejection device (44) for ejecting the tablets (48), the rotary tablet press further comprises a lubrication device for lubricating the upper and / or lower press punches (14, 16) with a lubricant; the lubricating device has a lubricant reservoir (54) and a stationary applicator connected to the lubricant reservoir (54) for applying lubricant to the upper and / or lower press punches (14, 16) which rotate together with the rotor and pass through the applicator; 1. A rotary tablet press, comprising: a lubricating device comprising a control device (52) designed to individually control the amount of lubricant applied by the applicator to the upper and / or lower press punches (14, 16) for each of the different upper and / or lower press punches (14, 16).

2. 2. The rotary tablet press of claim 1, wherein the applicator comprises at least one valve (56, 58, 60) for applying lubricant from the lubricant reservoir (54) to the outer surfaces of the upper and / or lower press punches (14, 16).

3. 3. The rotary tablet press of claim 2, wherein the at least one valve (56, 58, 60) is arranged in an internal space (68) radially arranged within a pitch circle described by the upper and / or lower press punches (14, 16), thereby applying the lubricant to the upper and / or lower press punches (14, 16) from the inside out.

4. 4. A rotary tablet press according to claim 2 or 3, characterized in that the at least one valve (56, 58, 60) is arranged to apply the lubricant to the upper and / or lower press punches (14, 16) from above, from below and / or from the side.

5. 5. A rotary tablet press according to any one of claims 2 to 4, characterized in that the at least one valve (56, 58, 60) is designed to apply lubricant intermittently at a frequency above 30 Hz, preferably above 100 Hz, even more preferably above 200 Hz, even more preferably up to 250 Hz.

6. 6. A rotary tablet press according to claim 1, characterized in that the control device (52) takes into account the rotational position of the rotor and / or the delay time of the applicator or of its valve (56, 58, 60) and / or the flight time of the lubricant from the applicator or of its valve (56, 58, 60) to the upper and / or lower press punch (14, 16) in order to control the applicator.

7. 7. A rotary tablet press according to claim 6, characterized in that the control device (52) takes into account the lubricant pressure, the temperature of the lubricant, the viscosity of the lubricant, the opening time of the applicator or the applicator valve (56, 58, 60), the outlet shape of the applicator or the applicator valve (56, 58, 60), and / or the distance between the applicator or the applicator valve (56, 58, 60) and the upper and / or lower press punch (14, 16) to ascertain the flight time of the lubricant.

8. 8. A rotary tablet press according to any one of claims 1 to 7, characterized in that the lubricant reservoir (54) comprises a press device (34) that holds the lubricant at a predetermined pressure.

9. 9. A rotary tablet press according to claim 1, wherein the control device (52) is designed to individually control the amount of lubricant applied by the applicator to the upper and / or lower press punches (14, 16) for each of the different upper and / or lower press punches (14, 16) by adjusting the size of the drop of lubricant applied by the applicator and / or the opening time of the applicator and / or the number of lubricant applications applied by the applicator to each individual upper and / or lower press punch (14, 16).

10. the controller (52) receives measurements from at least one sensor of the rotary tablet press; 10. A rotary tablet press according to any one of claims 1 to 9, characterized in that it is designed to individually control the amount of lubricant applied by the applicator to the different upper and / or lower press punches (14, 16) based on the received measurements.

11. 11. Rotary tablet press according to claim 10, characterized in that the at least one sensor comprises at least one stiffness sensor measuring the stiffness of the upper and / or lower press punch (14, 16) individually.

12. said lubricant reservoir (54) contains a liquid lubricant, in particular a lubricating oil; the applicator intermittently applies the liquid lubricant in drops to the upper and / or lower press punches (14, 16); and / or 12. A rotary tablet press according to any one of claims 1 to 11, characterized in that the applicator applies the liquid lubricant in a predetermined amount in an atomized state to the upper and / or lower press punches (14, 16).

13. 13. A rotary tablet press according to any one of claims 1 to 12, characterized in that the lubricating device comprises a heating device for heating the applicator.

14. 14. A method, characterized in that the upper and / or lower press punches (14, 16) are lubricated using a rotary tablet press according to any one of claims 1 to 13.

Images