Method for Producing Pressed Products and Assembly for Producing Pressed Products

Abstract

A method of manufacturing compacts and an arrangement for manufacturing compacts, in which the disadvantages of the state of the art are overcome and an efficient method and at the same time a simple construction and a simple implementation are achieved. This involves a method for manufacturing compacts, wherein after feeding the feedstock, pre-pressing into a pre-agglomerate using at least one pre-pressing punch or at least one stuffing screw and subsequently main pressing of the pre-agglomerate into a compact in at least one pressing die using at least one main pressing punch and subsequently ejection of the compact from the at least one pressing die are performed, pre-pressing, main pressing and ejection being performed in a mutually parallel working direction. This also involves an arrangement for manufacturing compacts, wherein at least one pressing die is provided in die tool receptacle with a feed for feedstock.

Claims

1. A method for manufacturing compacts by means of a die tool receptacle (2) rotating sequentially around a rotation axis (28), wherein after feeding of feedstock a volume reduction of the feedstock (11) is performed and subsequently main pressing of the feedstock into a compact and ejection of the compact are performed, characterized in that after feeding the feedstock (11), pre-pressing into a pre-agglomerate (12) using at least one pre-pressing punch (1) or at least one stuffing screw (17) and subsequently main pressing of the pre-agglomerate (12) into a compact in at least one pressing die (3) using at least one main pressing punch (21) and subsequently ejection of the compact from the at least one pressing die (3) by means of at least one ejection punch (23) are performed, pre-pressing, main pressing and ejection being performed simultaneously in a mutually parallel working direction at different fixed positions distributed in the circumferential direction and on one side at the respective position and the die tool receptacle (2) being at a standstill for this purpose.

2. The method according to claim 1, characterized in that pre-compacting of the feedstock (11) is performed for pre-pressing and/or pre-pressing into at least pre-pressed feedstock (11) or pre-agglomerate (12) is performed in the pressing die (3) and/or in a pre-pressing channel (7).

3. The method according to claim 1, characterized in that the at least one pressing die (3) is moved sequentially to the at least one pre-pressing punch (1) or the at least one stuffing screw (17), the at least one main pressing punch (21) and the at least one ejection punch (23).

4. The method according to claim 1, characterized in that each time one, two or more pre-pressing processes, main pressing processes and ejections are parallel or at the same time.

5. The method according to claim 1, characterized in that two or more successive pre-pressing processes are preformed, wherein the respective feedstock (11) is pressed against the respective preceding pre-agglomerate (12).

6. The method according to claim 1, characterized in that in case of two or more successive pre-pressing processes, the pre-agglomerates (12) are pushed one position further during pre-pressing, wherein each time one pre-agglomerate (12) is pushed into the pressing die (3) and/or, in case of two or more successive main pressing processes or ejections, the compacts are pushed out of the pressing die (3) or from the pressing die (3) into a shaping channel (30) having a region of a constriction (31), the respective compacts being pushed one position further into the shaping channel (30).

7. The method according to claim 1, characterized in that the pre-agglomerate (12) is pre-pressed into a positionally stable shape.

8. The method according to claim 1, characterized in that positioning of the pre-agglomerate (12) is performed in the pressing die (3).

9. The method according to claim 1, characterized in that the feeding of the feedstock (11) for pre-pressing is dynamically controlled, wherein the quantity of the fed feedstock (11) is influenced by means of the at least one pre-pressing punch (1) or by means of the pre-compacting unit (27).

10. The method according to claim 1, characterized in that the quantity of the feedstock (11) is adjusted based on the travel path of the pre-pressing punch (1).

11. The method according to claim 1, characterized in that the at least one pre-pressing punch (1) or the at least one stuffing screw (17) and/or the at least one main pressing punch (21) and/or the at least one ejection punch (23) act on respectively allocated pressing dies (3) at the same time.

12. method according to claim 1, characterized in that the main pressing process is performed alternately between at least two pressing dies (3) in die tool receptacles (2) spaced from each other.

13. An arrangement for manufacturing compacts, wherein at least one pressing die (3) is provided in a die tool receptacle (2) rotating sequentially around a rotation axis (28) with a feed (10) for feedstock (11) and wherein the at least one pressing die (3) is able to be arranged or moved correspondingly to at least one pre-pressing punch (1) or at least one stuffing screw (17), to at least one main pressing punch (21) and to at least one ejection punch (23), the working directions of the at least one pre-pressing punch (1) or of the at least one stuffing screw (17), of the at least one main pressing punch (21) and of the at least one ejection punch (23) being parallel to each other, wherein a counter-pressing plate (4) is provided on the side of the respective pressing die (3) opposite and/or facing the at least one pre-pressing punch (1) or die tool receptacle (2) and a counter-pressing plate (4) is provided on the side of the respective pressing die (3) opposite the at least one main pressing punch (21), the at least one pressing die being continuous (3) in the working direction.

14. The arrangement according to claim 13, characterized in that on the side of the respective one pressing die (3) opposite the at least one ejection punch (23), a shaping channel (30) with a region of a constriction (31) or a device or a device for discharging or further processing of the compacts is provided.

15. The arrangement according to claim 13, characterized in that the die tool receptacle (2) is preferably a round or polygonal die tool disc (2) or a die tool ring (2) rotatable around the rotation axis (28), wherein the at least one pressing die (3) is arranged in the at least one rotatable round or polygonal die tool disc (2) or die tool ring (2) as die tool receptacle (2), wherein, in case of two or more pressing dies (3), the pressing dies (3) are arranged distributed or offset in the circumferential direction in the die tool receptacle (2) as a rotatable round or polygonal die tool disc (2) or die tool ring (2), or the die tool receptacle (2) is preferably at least one radially arranged die tool arm (2) extending from the rotation axis (28) and rotatable around the rotation axis (28), wherein the at least one pressing die (3) is arranged in the at least one die tool arm (2), wherein, in case of two or more die tool arms (2) of the die tool receptacle (2) extending from the rotation axis (28) and rotatable around the rotation axis (28), the die tool arms (2) are distributed or offset around the rotation axis (28).

16. The arrangement according to claim 13, characterized in that the counter-pressing plate (4) is stationary or pivotable or movable.

17. The arrangement according to claim 13, characterized in that in case of two or more pressing dies (3), the at least one pre-pressing punch (1) or the at least one stuffing screw (17), the at least one main pressing punch (21) and/or the at least one ejection punch (23) are each allocated to one of the pressing dies (3).

18. The arrangement according to claim 13, characterized in that a feed of feedstock (11) is provided for the respective pressing die (3) or a common feed (10) of feedstock (11) for two or more pressing dies (3) is provided, wherein, in case of a common feed (10) of feedstock (11), the respective pressing dies (3) are arranged side by side in a horizontal plane in the region of the feed (10) of feedstock (11) and/or of pre-pressing.

19. The arrangement according to claim 13, characterized in that two die tool receptacles (2) are provided, wherein the two die tool receptacles (2) are spaced from each other and the at least one main pressing punch (21) is drivable alternately by a common main pressing cylinder (22) or drive arranged between the die tool receptacles (2).

20. The arrangement according to claim 13, characterized in that a pre-pressing channel (7) leads into the respective pressing die (3), wherein the at least one pre-pressing punch (1) or the at least one stuffing screw (17) is arranged in or leads into at least one pre-pressing channel (7) and/or the pre-pressing channel (7) has a tapered portion in the working direction.

21. The arrangement according to claim 13, characterized in that a positioning punch (5) is connected to the at least one pressing die (3), wherein the working direction of the positioning punch (5) is contrary to that of the pre-pressing punch (1).

22. The arrangement according to claim 13, characterized in that at least one pre-compactor (27) is arranged in the pre-pressing channel (7) or in the feed (11).

23. The arrangement according to claim 13, characterized in that the pre-compactor (27) is arranged at an angle of less than or equal to 90 degrees to the working direction of the pre-pressing punch (1).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0102] Several exemplary embodiments of the invention are illustrated in the drawings and are described in detail in the following. Of the drawings:

[0103] FIG. 1 shows a schematic illustration of an arrangement for a pressing process with a feedstock feed, a pre-pressing punch with a pre-pressing cylinder, a main pressing punch with a main pressing cylinder and an ejection punch with an ejection cylinder at a driveable, rotatable die tool disc with pressing dies arranged therein and a schematic illustration of a force-absorbing connection between the counter-pressing plates and the cylinders of the pre-pressing punch and of the main pressing punch, where the pre-pressing punch with the pre-pressing cylinder, the main pressing punch with the main pressing cylinder and the ejection punch with the ejection cylinder are arranged to be parallel and to have the same working direction.

[0104] FIG. 2 shows a schematic illustration of an arrangement for the pressing process with one feedstock feed, one pre-pressing punch with a pre-pressing cylinder, one main pressing punch at a main pressing cylinder operating as a synchronous cylinder and one ejection punch with an ejection cylinder on each of two drivable, rotatable die tool discs with pressing dies arranged therein, the die tool discs having a coincident rotation axis.

[0105] FIG. 3 shows a schematic illustration of an arrangement for a pressing process with a feedstock feed, a pre-pressing punch with a pre-pressing cylinder, a main pressing punch with a main pressing cylinder and an ejection punch with an ejection cylinder at a driveable, rotatable die tool disc with pressing dies arranged therein, where the pre-pressing punch with the pre-pressing cylinder and the main pressing punch with the main pressing cylinder are arranged to be parallel and to have the same working direction and the ejection punch with the ejection cylinder arranged to be parallel to the pre-pressing punch with the pre-pressing cylinder and to the main pressing punch with the main pressing cylinder, but is arranged with a contrary, i.e. opposite, working direction as well as with a pivotable counter-pressing plate between the pre-pressing punch or filling channel, respectively, and the pressing die.

[0106] FIG. 4 shows a schematic illustration of an arrangement for a pressing process with a feed for feedstock, a pre-pressing punch with a pre-pressing cylinder, a main pressing punch with a main pressing cylinder operating as a synchronous cylinder and an ejection punch with an ejection cylinder at each of two driveable, rotatable die tool discs with pressing dies arranged therein, where the die tool discs have a coincident rotation axis and in which the pre-pressing punch with the pre-pressing cylinder and the main pressing punch are arranged to be parallel and to have the same working direction and the main pressing punch with the main pressing cylinder is arranged to be parallel to each of the pre-pressing punch with the pre-pressing cylinder and the ejection punch with the ejection cylinder, however with a contrary, i.e. opposite, working direction,

[0107] FIG. 5 shows a schematic illustration as a sectional view of pre-pressing with a pre-pressing punch and feedstock feed into a filling channel,

[0108] FIG. 6 shows a schematic illustration as a sectional view of pre-pressing with a pre-pressing punch and with pre-pressed feedstock as a pre-agglomerate in the pressing die,

[0109] FIG. 7 shows a schematic illustration as a sectional view of pre-pressing with a pre-pressing punch and with feedstock feed and vertical pre-compaction by means of a pre-compaction punch, where a pre-pressing channel is provided in front of the pressing die, in which pre-compacted and already pre-pressed feedstock and an empty pressing die is provided for receiving pre-pressed feedstock as a pre-agglomerate,

[0110] FIG. 8 shows a schematic illustration as a sectional view of pre-pressing with a pre-pressing punch and with feedstock feed and vertical pre-compaction, where a pre-pressing channel is provided in front of the pressing die, in which pre-compacted feedstock is pre-pressed and already pre-pressed feedstock is present, and a pressing die is provided, in which a pre-agglomerate is pressed in and loose and uncompacted feedstock is already fed above the pre-pressing punch in the pressing position, the positioning punch having positioned the pre-agglomerate into the boundary region or transition region between the pre-pressing channel and the pressing die,

[0111] FIG. 9 shows a schematic illustration as a sectional view of pre-pressing with a pre-pressing punch and with feedstock feed and vertical pre-compaction by means of a stuffing screw as a pre-compaction screw, where a pre-pressing channel is provided in front of the pressing die, in which channel pre-compacted feedstock and already pre-pressed feedstock is present, and an empty pressing die is provided for receiving pre-pressed feedstock as a pre-agglomerate.

[0112] FIG. 10 shows a schematic illustration as a sectional view of pre-pressing with a pre-pressing punch and with feedstock feed and vertical pre-compaction, where a pre-pressing channel is provided in front of the pressing die, in which channel pre-compacted feedstock is pre-pressed and already pre-pressed feedstock is present, and a pressing die is provided, in which a pre-agglomerate is pressed in and loose feedstock and feedstock compacted by the stuffing screw as a pre-compacting screw is already fed above the pre-pressing punch in the pressing position,

[0113] FIG. 11 shows a schematic illustration as a sectional view of a pre-pressing unit with a pre-pressing punch and with feedstock feed, where a pre-pressing channel is provided in front of the pressing die with a tapering cross-section, in which already compacted feedstock, already pre-pressed feedstock and an empty pressing die is provided for receiving pre-pressed feedstock as a pre-agglomerate,

[0114] FIG. 12 shows a schematic illustration as a sectional view of a pre-pressing unit with a pre-pressing punch and with feedstock feed, where a pre-pressing channel is provided in front of the pressing die with a tapered cross-section, in which channel already pre-compacted feedstock and an empty pressing die is provided, into which a pre-agglomerate is pressed in, and a pre-pressing punch is provided in the pre-pressing channel, being in pre-pressing position.

[0115] FIG. 13 shows a schematic illustration as a sectional view of pre-pressing with a stuffing screw as a pre-pressing screw with a tapered cross-section and feedstock feed into and through the stuffing screw as a pre-pressing screw, where already compacted feedstock is present in front of the pressing die and an empty pressing die is provided for receiving pre-pressed feedstock as a pre-agglomerate,

[0116] FIG. 14 shows a schematic illustration as a sectional view of pre-pressing with a stuffing screw as a pre-pressing screw with a tapered cross-section and feedstock feed into and through the stuffing screw as pre-pressing screw, in which a pre-agglomerate is pre-pressed in front of and pressed into the pressing die,

[0117] FIG. 15 shows a schematic illustration of an arrangement for a pressing process with feedstock feed, a pre-pressing punch with a pre-pressing cylinder, a main pressing punch with a main pressing cylinder and an ejection punch with an ejection cylinder at a drivable, rotatable die tool disc with pressing dies arranged therein, where a shaping channel with a region of a constriction is provided on the side of the pressing die opposite the at least one ejection punch and an enlarged cylinder is arranged as a drive for the ejection punch,

[0118] FIG. 16 shows a schematic spatial illustration of an arrangement for a pressing process with a pre-pressing punch with a pre-pressing cylinder, having a counter-pressing plate on the side of the pressing die opposite the at least one pre-pressing punch and a main pressing punch with a main pressing cylinder having a counter-pressing plate on the side of the pressing die opposite the at least one main pressing cylinder and an ejection punch with an ejection cylinder and a shaping channel with a region of a constriction on the side of the pressing die opposite the at least one ejection punch, the ejection being into the shaping channel,

[0119] FIG. 17 shows a die tool receptacle as a die tool disc with pressing dies,

[0120] FIG. 18 shows a die tool receptacle as die tool arms with pressing dies, and

[0121] FIG. 19 shows a die tool receptacle as a die tool ring with pressing dies.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0122] The method according to the invention proposes an at least two-step pressing process in a die tool with the following sequence, where feedstock 11 is fed and after feeding the feedstock 11, pre-pressing into a pre-agglomerate 12 in at least one pressing die 3 is performed. This also causes a volume reduction of the feedstock 11. Depending on the feedstock 11 and on process design, pre-pressing is performed with at least one pre-pressing punch 1 or with at least one stuffing screw 17. Subsequently, main pressing of the pre-agglomerate 12 into a compact is performed in the at least one pressing die 3 with at least one main pressing punch 21. After main pressing, ejection of the compact from the at least one pressing die 3 is performed. Pre-pressing, main pressing and ejection are performed in a mutually parallel working direction.

[0123] In a specific exemplary embodiment, pre-pressing and main pressing are performed at the same time and in the same direction. Besides pre-pressing and main pressing being performed at the same time and in the same direction, opposite or co-directional pressing directions independently of each other and/or simultaneous or sequential pressing processes are provided.

[0124] Identical pressing directions are shown in FIGS. 1 to 3, 15 and 16. FIG. 4 shows opposite pressing directions for pre-pressing and main pressing.

[0125] Ejection or the ejection direction of the compact is determined by the respective subsequent process or by the periphery for further processing of the compact. Depending on the requirement, ejection is simultaneous or, departingly, sequential relative to at least one of the pressing processes of pre-pressing or main pressing. In addition and depending on the requirement, ejection is in the same direction or in opposite direction relative to at least one of the pressing processes of pre-pressing or main pressing.

[0126] In FIGS. 1, 2 and 15, ejection is in the same direction as pre-pressing and main pressing. In FIG. 3, ejection is in opposite direction to pre-pressing and main pressing. In FIG. 4, ejection is in opposite direction to main pressing and in the same direction as pre-pressing.

[0127] Alternatively to the exemplary embodiments of the arrangement according to the invention illustrated in FIGS. 3 and 4, it is also provided that the main pressing punch 21 and the ejection punch 23 act in the same working direction whereas the pre-pressing punch 1 acts in the contrary, i.e., opposite direction.

[0128] The feedstock 11 is conveyed into the pressing die 3 for pre-pressing and is pressed by means of the pre-pressing punch 1 or the stuffing screw 17 against a fixed counter-pressing plate 4 behind. In this way, a pre-agglomerate 12 is produced. The pressing die 3 is continuous. This facilitates pre-pressing and also main pressing against the counter-pressing plate 4, on the one hand, and ejection of the compact from the pressing die 3, on the other hand. Thus, the respective pressing directions can be selected according to the process requirements. The counter-pressing plate 4 is provided on the side of the pressing die 3 side opposite the pre-pressing punch 1 or stuffing screw 17 and the main pressing punch 21. This is shown in FIGS. 1 to 16.

[0129] A shaping channel 30 with a constriction 31, for example with stepwise reduced course in the specific exemplary embodiment, may be provided opposite the ejection punch 23, This is shown in FIG. 16. In this case, the compact is ejected by means of the ejection punch 23 from the pressing die 3 into the shaping channel 30 with a region of a constriction 31. Inside this shaping channel 30, a string of compacts is formed, the respective compacts being pushed one position further into the shaping channel 30 at each ejection.

[0130] Depending on the embodiment, the respective pressing dies 3 each are moved from the pre-pressing position, i.e. from the pre-pressing of the fed feedstock 11 into the pre-agglomerate 12 by means of the respective pre-pressing punch 1 or respective stuffing screw 17, into the main pressing position, i.e. to the respective main pressing punch 21 for the main pressing of the pre-agglomerate 12 into a compact, and into the ejection position, i.e. for ejecting the compact by means of the at least one ejection punch 23.

[0131] For this purpose, the respective pressing dies 3 are arranged in at least one die tool receptacle 2. Preferably, the die tool receptacle 2 is a round or polygonal die tool disc 2 or die tool ring 2 rotatable around a rotation axis 28, or at least one radially arranged die tool arm 2 extending from the rotation axis 28 and rotatable around the rotation axis 28, in which the continuous pressing die 3 or the continuous pressing dies 3 are arranged.

[0132] Depending on the embodiment and demand, one or several pressing dies 3 are arranged to be distributed in the respective die tool receptacle 2. Thus, multiple pressing dies 3 can be provided for pre-pressing and main pressing and, if separate, for ejection. Thus, with two or more pressing dies, pre-pressing punches 1 or stuffing screws 17 are allocated to one group of pressing dies 3, main pressing punches 21 are allocated to another group of pressing dies 3 and ejection punches 23 are allocated to yet another group of pressing dies 3, whereby a high efficiency of the method is achieved. For this purpose, the pressing dies 3 can be arranged such that the next pressing process is performed either at each sequential rotation of the die tool receptacle 2 or at a later sequential rotation of the die tool receptacle 2.

[0133] By the rotating movement of the die tool receptacle 2 around the rotation axis 28, the pressing dies 3 are sequentially moved to different fixed positions distributed in the circumferential direction, from pre-pressing to main pressing, from main pressing to ejection as well as from ejection again to pre-pressing. The rotating movement is sequential, and thus the die tool receptacle 2 is sequentially rotating since the die tool receptacle 2 stands still for each pressing process.

[0134] Corresponding to the pressing dies 3 allocated to pre-pressing, pre-pressing punches 1 are provided. Likewise, main pressing punches 21 are provided corresponding to the pressing dies 3 allocated to main pressing and, if separate, ejection punches 23 are provided corresponding to the pressing dies 3 for ejection. Consequently, several pressing dies can be provided, preferably arranged such that pre-pressing, main pressing and ejection, if separate, can be performed simultaneously and plurally.

[0135] Thus, in a specific exemplary embodiment, the respective pressing die 3 with the pre-agglomerate 12 therein is moved by means of a sequentially rotating die tool disc 2 until in front of the main pressing punch 21. Now, main pressing is performed in the same pressing die 3 at a high pressure. The pressure is determined by the feedstock 11 and the design of the main pressing punch 21 and the drive of the main pressing punch 21.

[0136] In the specific exemplary embodiment, hydraulic cylinders are used as pre-pressing cylinder 9, main pressing cylinder 22 and ejection cylinder 24 to drive the pre-pressing punch 1, the main pressing punch 21 and the ejection punch 23.

[0137] In the specific exemplary embodiments, the drive for the die tool receptacle 2 is a stepper motor or a servo-motor.

[0138] It is possible that two or more pre-pressing, main pressing and/or ejection processes can be performed individually or groupwise in parallel as well as at the same time.

[0139] Accordingly, the respective pre-pressing punches 1 or stuffing screw 17, the at least one main pressing punch 21 as well as the respective provided ejection punches 23 act successively or at the same time on the respective allocated pressing die 3 or allocated pressing dies 3. The respective pre-pressing punches 1 or the respective stuffing screw 17, the at least one main pressing punch 21 as well as the respective provided ejection punches 23 each act unilaterally on the respective allocated pressing die 3 or allocated pressing dies 3. With this method, the respective pre-pressing punches 1 or the respective stuffing screw 17, the at least one main pressing punch 21 as well as the respective ejection punches 23 provided can act in the same direction or different directions on the respective allocated pressing die 3 or allocated pressing dies 3. However, the respective directions are parallel to each other. The respective pressing die(s) 3 are arranged at different fixed positions distributed in the circumferential direction on the die tool receptacle 2 that sequentially rotates around a rotation axis 28.

[0140] In a specific exemplary embodiment, the compact is ejected or demoulded from the pressing die 3 by means of an ejection punch 23 with a small hydraulic cylinder as ejection cylinder 24 after a further rotating movement of the die tool receptacle 2. Ejection can be as a loose drop on a conveyor belt, into a fixed receptacle or to a subsequent process.

[0141] In an alternative embodiment, ejection by means of the ejection punch 23 is performed into a shaping channel 30 that has a constriction 31 with a conical course and subsequent flare. This allows the counter-pressure produced to be smaller than that of the main pressing punch 21 since the compact is already fully pressed and only needs to be conveyed into the shaping channel 30. Depending on the peripheral process and pressure conditions, the compacts may be required to seal the shaping channel 30. Likewise, inside the shaping channel 30, a string of compacts is formed, the respective compacts being pushed one position further into the shaping channel 30.

[0142] After ejection of the compact, the pressing process starts again with the feeding of the feedstock 11, pre-pressing of the feedstock 11 into a pre-agglomerate 12, main pressing of the pre-agglomerate 12 into a compact and subsequent ejection, the pressing die 3 being moved for pre-pressing, main pressing and ejection.

[0143] Pre-pressing can be done in various ways, as shown in FIGS. 5 to 14.

[0144] As shown in FIGS. 5 and 6, a pre-pressing punch 1 with a hydraulic cylinder of a small diameter as the pre-pressing cylinder 9 receives the feedstock 11 in loose and uncompacted form in the pre-pressing channel 7 below the filling duct 8 and conveys it directly into the pressing die 3 which is provided or mounted in or on the sequentially rotating die tool receptacle 2. Only when the feedstock 11 has been conveyed into the pressing die 3 is the necessary pre-pressing pressure built up and the pre-agglomerate 12 thus produced. As shown, the pre-pressing channel 7 leads into the pressing die 3.

[0145] FIGS. 7 to 10 show that a pre-pressing punch 1 with a hydraulic cylinder of a small diameter as the pre-pressing cylinder 1 receives the feedstock 11 which has already been pre-compacted in the filling duct 8, for example by means of a stuffing screw 17, as shown in FIGS. 9 and 10, or by means of a vertical compactor 27 as a pre-compacting punch 14, as shown in FIGS. 7 and 8, and conveys the pre-compacted feedstock 11 into the pressing die 3, whereby the appropriate pre-pressing pressure is built up and the pre-agglomerate 12 is formed for the subsequent main pressing process. Pre-pressing with the pre-compactor 27 can be performed from above at an angle of less than or equal to 90 degrees to the movement direction of the pre-pressing punch 1, i.e., inclined towards the drive of the pre-pressing punch 1 or inclined away from the pressing die 3, respectively, whereby the pre-compaction is performed in the direction of the subsequent pre-pressing. The pre-compaction drive can be implemented by means of a hydraulic cylinder, pneumatic cylinder, linear motor or by means of a pre-compaction unit driven by a worm gear.

[0146] FIGS. 7 to 10 further show that pre-pressing by means of the pre-pressing punch 1 is also performed already outside the pressing die 3 in the pre-pressing channel 7. Here, several pre-agglomerates 12 are waiting in line in the pre-pressing channel 7, and each time fed feedstock 11 is pre-pressed, the “string” of pre-agglomerates 12 is pushed one position further. Thereby, each time exactly one pre-agglomerate 12 is conveyed into the pressing die 3. The pressure required for pre-pressing is built up already in the pre-pressing channel 7 on the loose feedstock 11 that has been fed last by pressing the feedstock 11 against the preceding pre-agglomerate 12. Thus, a pre-pressing series is performed as multiple pre-pressing. By conveying the respective pre-agglomerate 12 into the pressing die 3, the pre-pressing thereof is complete. As shown, the pre-pressing channel 7 leads into the pressing die 3.

[0147] The respective drives of the pre-pressing punches 1 or pre-compaction punches 14 shown in FIGS. 5 to 12 may be hydraulic cylinders as the pre-pressing cylinder 9 or pre-compaction cylinder 15, only the piston rods 9 of the respective pre-pressing punches 1 or of the pre-pressing cylinder 9 as well as the pistons rods 15 of the respective pre-compaction punches 14 pre-compaction cylinder 15 being shown for simplification.

[0148] Likewise simplistically, only the piston rod 6 of the positioning punch 5 or positioning cylinder 6 is shown exemplarily of the positioning punch 5 in FIGS. 5 to 14.

[0149] As shown in FIGS. 13 and 14, the pre-pressing channel has a tapered portion, whereby the pre-agglomerates are further compacted inside the pre-pressing channel. The tapered portion of the pre-pressing channel 7 can also be combined with pre-compaction unit.

[0150] Pre-pressing by means of a stuffing screw 17 is shown in FIGS. 13 and 14. In this case, operation of a pre-pressing punch 9 is dispensed with, and instead a continuous string of compacted feedstock 11 is conveyed into the pressing die 3 by means of the stuffing screw 17. This string is shorn off during the sequential rotation of the die tool receptacle 2. As shown, the pre-pressing channel 7 leads into the pressing die 3.

[0151] Feeding of the feedstock 11 for pre-pressing is dynamic, with the quantity of the fed feedstock 11 being influenced by means of the at least one pre-pressing punch 1 or by means of the pre-compacting unit 27 so that the sizes of the pre-agglomerates 12 are preferably equalized. For this purpose, the travel path of the pre-pressing punch 1 or drive is measured and the quantity of the feedstock 11 is adjusted based on the measurement. For example, based on travel path measurement, the pre-pressing punch 1 is thus only retracted as far as to allow the desired quantity of feedstock 11 to get in front of the pre-pressing punch 1 or into the pre-pressing channel 7 in front of the pre-pressing punch 1. Depending on the feedstock 11, this either already falls towards the pressing die 3 so that, depending on the feedstock 11, the pre-pressing punch 1 does not have to unblock the input opening 10 or feed 10 for the feedstock 11. This varies depending on the feedstock 11 and the individual state thereof. Depending on the quantity of the fed feedstock 11, the travel path of the pre-pressing punch 1 varies during pre-pressing. Accordingly, the pre-pressing punch 1 is moved for a subsequent pre-pressing process in an adapted manner such that the required quantity of feedstock 11 is fed or gets in front of the pre-pressing punch 1.

[0152] Pre-pressing presses the feedstock 11 into a pre-agglomerate 12 of a positionally stable shape.

[0153] Due to the aggregate being built in a modular manner, an optimal pre-pressing device can be implemented for the respective feedstock 11. The pre-pressing device to be used largely depends on the conveying properties of the respective feedstock 11 as well as on the relationship between the bulk density and the subsequent density of the compact. This offers the possibility to apply the optimal solution in terms of energy and process-technology depending on the feedstock 11.

[0154] For exact positioning of the agglomerate 12 in the pressing die 3, a positioning unit is provided. For this purpose, a positioning punch 5 is provided on the side of the pressing die 3 opposite the respective pre-pressing punch 1 and with a main working direction contrary to the pre-pressing punch 1. A positioning punch 5 is provided in each of FIGS. 5 to 14. The positioning punch 5 is arranged in the counter-pressing plate 4 in each case.

[0155] In FIG. 8, the positioning punch 5 is extended as far as to push the pre-agglomerate 12 in the pressing die 3 back to an extent that the surface boundary 17 thereof as the contact surface 17 to the pre-agglomerate 12 that follows in the pre-pressing channel 7 is in alignment with the surface of the die tool receptacle 2, for example as a die tool disc 2.

[0156] Furthermore, positioning of the pre-agglomerate 12 can be required if the feedstock has residual elasticity and relaxes and expands after pre-pressing both in the direction of the pre-pressing punch 1 and in the direction of the counter-pressing plate 4. By positioning, the pre-agglomerate 12 is pushed into a central position in the pressing die 3 so that the pre-agglomerate 12 does not protrude from the pressing die 3. Positioning can also be required if the pre-agglomerates 12 have different sizes due to different feedstock quantities or pre-pressing cycles or, depending on the feedstock 11, have a uniform small size and a plurality of pre-agglomerates 12 is present inside the pre-pressing channel 7, which however fit in the pressing die 3 together, depending on their size. Thus, this may also require a correction of the position to be performed.

[0157] The arrangement for manufacturing compacts according to the invention comprises at least one pressing die 3 in at least one die tool receptacle 2 with a feed 10 for the feedstock 11. Correspondingly to the respective pressing die 3, a pre-pressing punch 1, as shown in FIGS. 1 to 12, 15 and 16, or a stuffing screw 17, as shown in FIG. 13 or 14, are arranged. Furthermore, as shown in FIGS. 1 to 4 and 15 and 16, one main pressing punch 21 is arranged correspondingly to one pressing die 3. As shown in FIGS. 1 to 4, 15 and 16, the die tool receptacle 2 is rotatable so that the pressing dies 3 can move from the pre-pressing punch 1 to the main pressing punch 21 and, if provided, to the ejection punch and again to the pre-pressing punch 1.

[0158] The working direction of the respective pre-pressing punch 1 or the respective stuffing screw 17 and the respective main pressing punch 21 is mutually parallel, as shown in FIGS. 1 to 4, 15 and 16. The at least one pressing die 3 is continuous in working direction.

[0159] On the side of the pressing die 3 opposite the pre-pressing punch 1, a counter-pressing plate 4 covering the cross-section of the pressing die 3 is provided, as in FIGS. 1 to 16. The counter-pressing plate 4 is arranged to absorb the pre-pressing forces so that these do not act or act only minimally on the die tool receptacle 2. The counter-pressing plate 4 and the drive of the pre-pressing punch 1, for example a hydraulic cylinder, are constructively coupled via a force-absorbing connection 26 so that the pressing process towards the die tool receptacle 2 is almost stressless. The force-absorbing connection 26 is schematically shown in FIG. 1.

[0160] Furthermore, on the side of the pressing die 3 opposite the main pressing punch 21, a counter-pressing plate 4 is also provided depending on the embodiment, as shown in FIGS. 1 to 4 and 15, or a shaping channel 30 with a region of a constriction 31, as shown in FIG. 16. The counter-pressing plate 4 and the drive of the main pressing punch 1, for example a hydraulic cylinder as the main pressing cylinder 22, are also constructively coupled via a force-absorbing connection 26 so that the pressing process towards the die tool receptacle 2 is almost stressless. The force-absorbing connection 26 is also schematically shown in FIG. 1.

[0161] Furthermore, if ejection is not performed by the main pressing punch 21, at least one ejection punch 23 is provided, as shown in FIGS. 1 to 4 and 15. As shown in FIG. 15, a shaping channel 30 with a region of a constriction 31 is provided on the side of the pressing die 3 opposite the at least one ejection punch 23 or a device for discharging or further processing is provided (not shown). This device for discharging or further processing can be a conveyor belt or a collection box.

[0162] In one exemplary embodiment, as shown in FIG. 17, the die tool receptacle 2 is a round die tool disc 2 rotatable around a rotation axis 28. An alternative embodiment of the die tool receptacle 2 is a die tool ring 2 as shown in FIG. 19. The respective pressing dies 3 are distributed in the round die tool receptacle 2 in the circumferential direction, each offset by 120 degrees, and in the die tool ring 2 each offset by 90 degrees. As shown in FIG. 17, the pressing dies 3 are arranged in twos or pairs in the die tool disc 2.

[0163] In the exemplary embodiment as shown in FIG. 18, the die tool receptacle 2 comprises four die tool arms 2 extending radially from a rotation axis 28 and rotatable around the rotation axis 28. The respective pressing dies 3 are arranged in the die tool arms 2. The radially arranged die tool arms 2 of the die tool receptacle 2 and rotatable around the rotation axis 28 are distributed or offset by 90 degrees.

[0164] For example, it is provided to have at least one feed of feedstock 11 for each pressing die 3 or to have a common feed 10 for feedstock 11 for two or more pressing dies 3. With a common feed 10 of feedstock 11, the respective pressing dies 3 are arranged side by side in a horizontal plane in the region of the feed 10 of feedstock 11, as shown in FIG. 17.

[0165] According to the exemplary embodiment as shown in FIG. 1, the pre-pressing punch 1, the main pressing punch 21 and the ejection punch 23 are arranged at a die tool receptacle 2 as die tool disc 2 to be mutually parallel and to have the same working direction. The feed 10 of the feedstock 11 is from a filling duct 8 into the pre-pressing channel 7. The respective punches 1, 21, 23 are driven by hydraulic cylinders. A motor 25 drives the die tool receptacle 2 as a die tool disc 2 sequentially or stepwise. Counter-pressing plates 4 are provided at the sides of the pressing dies 3 opposite the respective pressing punches 1, 21.

[0166] In addition to the arrangement as shown in FIG. 1, the exemplary embodiment in FIG. 2 has another die tool receptacle 2 as die tool disc 2 which is spaced from the first die tool disc 2 and has the same rotation axis 28. The at least one respective main pressing punch 21 is alternately driveable by a common main pressing cylinder 22 operating as a synchronous cylinder arranged between the die tool receptacles 2.

[0167] In deviation from FIG. 1, the exemplary embodiment in FIG. 3 has an ejection punch 23 with a working direction contrary to the pressing punches 1, 21. Furthermore, a pivotable counter-pressing plate 4 is provided between the pre-pressing punch 1 or filling channel 7 and the pressing die 3, against which pre-pressing is performed already in the filling channel 7 and, if present, also in the pre-pressing channel. After pre-pressing, the counter-pressing plate 4 is pivoted away and unblocks the way to the respective pressing die 3 leading into the respective pressing die 3 for the pre-agglomerate 12 to be pushed into the pressing die 3.

[0168] In deviation from FIG. 2, the exemplary embodiment in FIG. 4 has pre-pressing punches 1 and an ejection punches 23 with a working direction contrary to the respective main pressing punch 21. The main pressing cylinder 22 that drives the main pressing punch 21 works alternately as a synchronous cylinder

[0169] In deviation from FIG. 1 and according to the exemplary embodiment in FIG. 15, a shaping channel 30 is arranged on the pressing die 3 side opposite the ejection punch 23 and has a conical and local tapered portion 31, into which the compacts are conveyed when ejected.

[0170] FIG. 16 shows an arrangement for manufacturing compacts, where three pressing dies 3 are provided in a die tool receptacle 2 as die tool disc 2, one pre-pressing punch 1 and one main pressing punch 21 being arranged correspondingly to two of the pressing dies 3. The working direction of the pre-pressing punch 1 and the at least one main pressing punch 21 is parallel to each other and in the same direction. A counter-pressing plate 4 is arranged on the side of the pressing die 3 opposite the pre-pressing punch 1, and a shaping channel 30 with a region of a constriction 31 is arranged on the side of the pressing die 3 opposite the main pressing punch 21. In addition, a movable counter-pressing plate 4 is arranged between the shaping channel 30 and the pressing die 3. The pressing dies 3 is continuous in working direction. The pre-pressing punch 1 movably arranged in a pre-pressing channel 7. The pre-pressing channel 7 leads into the pressing die 3 and has a feed 10 for feedstock 11.

[0171] Although FIG. 16 shows a pre-pressing punch 1 and a main pressing punch 21, more than one pre-pressing punch 1 and one main pressing punch 21 can be arranged individually or in groups or alternately in an even distribution in the circumferential direction of the rotary movement of the die tool disc 2, the die tool ring 2 or the die tool arm 2. This advantageously achieves that the force that may be introduced into the die tool disc 2, the die tool ring 2 or the die tool arm 2 acts evenly, thus preventing or at least reducing lever forces acting on the drive and the bearing. According to the arrangement of the pre-pressing punches 1 and main pressing punches 21, the respective pressing dies are also arranged in a corresponding distribution or arrangement, or vice versa, according to the arrangement of the pressing dies in an even distribution in the circumferential direction of the rotating movement of the die tool disc 2, of the die tool ring 2 or of the die tool arm 2, the pre-pressing punch 1 and the main pressing punch 21 are correspondingly arranged to be able to operate the pressing dies at the same time at least for one step, for example main pressing or pre-pressing.

LIST OF REFERENCE NUMERALS

[0172] 1—Pre-pressing punch [0173] 2—Die tool disc, die tool ring, die tool arm, die tool receptacle [0174] 3—Pressing die [0175] 4—Counter-pressing plate [0176] 5—Positioning punch [0177] 6—Piston rod of positioning punch, positioning cylinder [0178] 7—Pre-pressing channel, filling channel [0179] 8—Filling duct [0180] 9—Piston rod of pre-pressing punch, pre-pressing cylinder [0181] 10—Input opening, feedstock feed [0182] 11—Feedstock [0183] 12—Pre-agglomerate [0184] 13—Bulk-free space [0185] 14—Vertical pre-compaction punch [0186] 15—Piston rod of pre-compaction punch, pre-compaction cylinder [0187] 16—Pre-compacted feedstock [0188] 17—Stuffing screw [0189] 18—Contact area of two pre-agglomerates, boundary surface of pre-agglomerate [0190] 19—Feedstock movement direction [0191] 20—Punch movement direction [0192] 21—Main pressing punch [0193] 22—Piston rod of main pressing punch, main pressing cylinder [0194] 23—Ejection punch [0195] 24—Piston rod of ejection punch, ejection cylinder [0196] 25—Motor [0197] 26—Force-absorbing connection [0198] 27—Pre-compacting unit [0199] 28—Rotation axis [0200] 29—Rotary movement [0201] 30—Shaping channel [0202] 31—Constriction [0203] 32—Pre-compaction punch