Pressing device for the production of pressed bales from straw
The pressing device addresses the challenge of achieving high-density, dimensionally accurate straw bales by using adjustable walls and opposing press carriage movements, enhancing production efficiency and reducing mechanical stress.
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- HOLZ JURGEN
- Filing Date
- 2025-02-25
- Publication Date
- 2026-06-11
AI Technical Summary
Existing pressing devices for producing straw bales for building insulation struggle to achieve high material density and dimensional accuracy while maintaining a simple design and efficient production.
A pressing device with a press chamber and adjustable press carriage, equipped with additional pressing devices on movable walls, and a drive unit that operates press carriages in opposite directions to reduce dynamic forces, allowing for efficient compression and uniform density.
The device achieves improved dimensional accuracy and uniform density in straw bales with reduced operational forces, increased production efficiency, and minimized mechanical stress, ensuring high-quality bales for building insulation.
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Abstract
Description
[0001] The invention relates to a pressing device for the production of pressed bales from straw.
[0002] It is known to construct modular building elements in the form of rectangular wooden frames with multiple compartments, into which compressed straw bales are inserted for thermal and acoustic insulation. Such a building element in timber frame construction is described, for example, in AT 510 797 A1. This building element can be used, for instance, as an exterior or interior wall for residential buildings or other structures.
[0003] To comply with legal regulations, especially with regard to strength, insulation properties, but also fire and insect protection, it is necessary to manufacture the straw bales with a high material density while maintaining high dimensional accuracy.
[0004] German patent application DE 10 2007 036 293 A1 discloses an agricultural baler with a press piston for conveying the harvested crop into a press channel surrounded by a press ring with lateral pressing devices. By means of these pressing devices, an upper press flap and side walls can be moved in such a way as to reduce the cross-sectional area of the press channel for compressing the crop. The finished, bound bale is then placed in the field.
[0005] The invention is based on the objective of creating a pressing device with simple design measures which is suitable for efficiently producing pressed straw bales suitable for use in building walls.
[0006] This problem is solved according to the invention by the features of claim 1. The dependent claims specify advantageous further developments.
[0007] The press device according to the invention for producing straw bales that can be used in building walls has at least one press chamber for receiving straw, to which a press carriage is assigned for compressing the straw in the press chamber. The press carriage is adjustable between a retracted starting position and a forward pressing position in which the straw in the press chamber is subjected to a pressing force. The press carriage is driven by means of a drive device, which is designed in particular such that the press carriage performs a translational movement when moving between the starting position and the pressing position.
[0008] In addition to the press carriage, the press chamber is equipped with an additional pressing device, which allows for the adjustment of a movable wall of the press chamber or an adjustment plate on the inner wall. In a preferred embodiment, the press chamber has an open side on the side of the press carriage to allow the straw to be fed in via the press carriage. The additional pressing device, on the other hand, is able to adjust a movable wall of the press chamber, which advantageously adjoins the open side of the press chamber, and also apply a pressing force to this wall. This makes it possible to compress the bale from two different sides, resulting in improved dimensional accuracy of the straw bale and a more uniform density.
[0009] It may be advantageous to arrange additional pressing devices on two different movable walls of the press chamber that are adjacent to each other, so that the compressed bale can be subjected to a pressing force in all three spatial directions. However, it is generally sufficient for only one wall of the press chamber to be movable and for only one pressing device to be present, which allows adjustment of the movable wall. In a preferred embodiment, the upper wall of the press chamber is movable, and the additional pressing device is located above the press chamber. Alternatively, a side wall of the press chamber can also be movable.
[0010] The movable wall of the press chamber is mounted in a sliding manner. During the adjustment movement, the wall is moved translationally in such a way that its orientation remains unchanged and it is parallel to its original position in all adjusted positions.
[0011] The movable wall advantageously forms an outer wall of the press chamber, limiting its volume. However, it is also possible for the movable wall to be designed as an adjustable wall located on the inside of an outer wall of the press chamber.
[0012] The additional pressing device can move a wall of the pressing chamber or a positioning plate that is part of the wall or is designed independently of the wall and located on the inside of the wall.
[0013] The additional pressing device can also be designed in such a way that the press bale is pushed out of the press chamber by the pressing device and pushed under a wedge device, whereby the press bale also experiences a compressing force.
[0014] According to a further advantageous embodiment, the maximum open position of the movable wall of the press chamber is limited by a stop. Accordingly, the maximum volume of the press chamber is also limited by the stop. When the straw in the press chamber is subjected to pressure from the press slide, an outward force can be exerted on the movable wall. The stop ensures that, despite this force, the movable wall is not pushed further outwards. The stop is formed, for example, by projections on the adjacent press chamber walls that extend inwards into the press chamber.
[0015] The additional pressing device is preferably hydraulically or pneumatically designed and accordingly includes a hydraulic or pneumatic actuating cylinder.
[0016] The baling device has at least a first and a second baling chamber for receiving straw, each baling chamber being assigned a baling slide for compressing the straw within the chamber. Each baling slide is adjustable between a retracted starting position and a forward position in which the straw in the baling chamber is subjected to a pressing force. The two baling slides are driven by a common drive unit located between the two opposing baling chambers. The drive unit is configured such that the two baling slides move in opposite directions when transitioning between the starting position and the pressing position.
[0017] This baling device offers several advantages. Firstly, despite the increased output of bales, the device is subjected to only relatively low forces, even though significant pressing force is required to produce the bales, with which each press carriage applies pressure to the straw in the baling chamber. This reduction in force is achieved through the inventive design of the drive unit in the baling device, which is arranged centrally between the two opposing baling chambers and moves the two press carriages in opposite directions. Accordingly, the pressing forces acting on the straw in each baling chamber are also directed in opposite directions. Due to the opposing movements of the press carriages, the dynamic forces in the drive unit cancel each other out or are at least significantly reduced.The same applies to the reverse movement when transferring from the pressing position to the starting position, since in this case, too, the respective return movements of the two press slides are directed in opposite directions, and the forces therefore cancel each other out. Particularly at the reversal points of the movement during the transition from the pressing direction to the return direction and vice versa, which are each associated with high forces, the forces in the drive mechanism cancel each other out or largely cancel each other out.
[0018] In this way, the components of the drive unit are largely relieved of the dynamic forces that occur at the reversal points of the press slides. Furthermore, the other components of the press, particularly those firmly fixed to the floor, such as a support frame, are also relieved of the high forces that arise during the movement of the press slides. This ensures that the entire press is not subjected to increased shocks, vibrations, or oscillations during operation, which could disrupt the pressing process and potentially damage components of the press.
[0019] Secondly, the baling machine can be operated more efficiently by simultaneously filling both baling chambers with straw and compressing the straw into a bale. In this configuration, the baling machine achieves a higher production rate of bales per unit of time than a baling machine with only one chamber.
[0020] Alternatively, it is also possible to fill only one of the press chambers with straw and compress it by the associated press carriage. In this configuration as well, the two press carriages perform opposing movements, thereby significantly reducing the dynamic forces in the drive mechanism.
[0021] In an advantageous embodiment, the drive unit comprises an eccentric device for adjusting the two press slides in opposite directions. The drive unit includes, for example, a motor-driven drive disc which drives the two opposing press slides, the connection between the drive disc and the two press slides being made via the eccentric device. This device comprises, for example, two connecting rods, one of which is assigned to each press slide, wherein the connecting rod is connected at one end directly or indirectly, in particular by pivot, to the drive disc and at the other end, pivotally connected to the press slide at a distance from the axis of rotation of the drive disc. Advantageously, at least one drive shaft of the drive disc is rotatably mounted in the press device, with the two connecting rods being oriented relative to the axis of rotation of the drive shaft.The drive discs are arranged axially offset from each other. This ensures that both press slides can be driven via the axially offset connecting rods and that the drive disc can perform a continuous rotational movement without reversing the rotation for the pressing process and the return process of the press slides.
[0022] The eccentric device converts the rotary drive movement of the drive disc into a preferably translational sliding movement of the press slides. The press slides can optionally be mounted in guide rails or similar devices within the press fixture, either rolling or sliding, to achieve a defined movement pattern.
[0023] The drive shaft of the drive pulley is rotatably mounted in a support frame of the press device, which accommodates both the press chambers and the drive unit. The shaft of the drive unit, extending orthogonally to the adjustment direction of the press slides, advantageously has three bearing points along its axial length, located at the ends and in the middle of the shaft.
[0024] The connecting rods are articulated to each drive arm, with the two drive arms being rotationally fixed to the drive shaft and advantageously located on opposite axial sides of the central bearing point of the drive shaft. This ensures that dynamic forces acting on the shaft due to the axial offset of the two connecting rods and the press slides are distributed evenly across the support frame of the press device via the bearing points. At least one bearing is provided at each bearing point.
[0025] The press has two further press chambers, also arranged opposite each other, parallel to the first two opposing press chambers. Each of these additional press chambers is also assigned a press carriage and a common, additional drive unit. The design of the additional drive unit is identical to that of the first drive unit, which drives the first two press carriages. This design doubles the capacity. Advantageously, the production of straw bales in the additional press chambers can be carried out independently of the straw bale production in the first two press chambers. For this purpose, the two drive units can be operated independently of each other. The design is particularly symmetrical with respect to a central longitudinal axis of the press.The drive units can be arranged symmetrically to each other and be of identical construction. The drive shafts of the drive units, to which the connecting rods are fixedly mounted and which drive the press slides, are coaxial to each other, but they are mounted independently and are designed separately. Each drive unit also has its own drive motor, in particular an electric motor, which, for example, drives the respective drive pulley via a belt. Alternatively, a single drive unit can be used for both drive units.
[0026] According to yet another advantageous embodiment, the baling device has a straw feed unit for conveying straw to a storage point located in front of the baling chamber. The storage point is situated in front of the open side of the baling chamber, so that the straw conveyed to the storage point is caught by the baling carriage and pressed into the baling chamber. It is particularly advantageous for the baling carriage to continuously perform a forward pressing movement and a reverse retraction movement, with the storage point for the straw being exposed in the retracted starting position, so that straw can be conveyed to the storage point by actuating the straw feed unit. In the next cycle, this straw can again be pressed into the baling chamber by the advancing baling carriage.
[0027] Possible configurations include systems where, at each retracted starting position of the press carriage, straw is conveyed to the storage point in front of the press chamber via the straw feed device. Alternatively, it is also possible to activate the straw feed device and convey straw to the storage point in front of the press chamber not at every retracted starting position, but only at some of the retracted positions of the press carriage.
[0028] According to another advantageous embodiment, the straw feed device is located below the press chamber and the straw is gathered from a delivery point below the press chamber by means of the straw feed device and conveyed upwards to the storage point immediately in front of the press chamber.
[0029] In an alternative design, straw is fed into the press chamber not from below, but from above or from the side.
[0030] The straw feeding device advantageously comprises a conveying arm and a conveying channel, the operation of which transports straw from a delivery position through the conveying channel to the depositing point in front of the opening of the baling chamber. The conveying arm is, in particular, articulated and performs a pivoting movement during conveying. The conveying movement includes gathering or grasping the straw deposited in front of the conveying channel and transporting the straw through the conveying channel to the depositing point.
[0031] It may be advantageous for the conveying arm to perform two different movements during the conveying process. This particularly involves a superposition or sequential movement of two rotary pivoting motions. Each movement can be assigned its own drive unit, especially an electric drive motor.
[0032] The pressing device has an ejection mechanism for pushing the press bales out of the pressing chamber. After the press bales are formed, they are initially still in the pressing chamber and are pushed out by means of the ejection mechanism, which in particular includes an ejection cylinder. The ejection cylinder acts on a sliding plate located on the inside of a wall of the pressing chamber. The ejection cylinder protrudes through a recess in the wall and adjusts the sliding plate to eject the press bale. Advantageously, the ejection direction is perpendicular to the adjustment direction of the press carriage and also perpendicular to the adjustment direction of the additional pressing device, which allows adjustment of a wall of the pressing chamber.To carry out the ejection, it is advantageous to open the wall of the press chamber opposite the ejection device to allow for the desired ejection path. The pressed bale is preferably ejected to a collection platform on the press, where it can be deposited. Alternatively, instead of a collection platform, the pressed bale can be ejected towards a robot gripper or inserted into a receptacle of a robot gripper. The robot gripper then picks up the pressed bale and transports it to its next use.
[0033] Instead of an extension cylinder, an electrically adjustable spindle can also be used.
[0034] The invention also relates to a method for actuating the aforementioned press device. The drive unit is configured such that the press carriage is continuously moved back and forth in only one direction of rotation during a continuous rotation of the drive disc. This occurs, for example, at a frequency of preferably one to three, for example two, adjustment movements per second, in which the press carriage is moved between the retracted starting position and the advanced pressing position. Advantageously, the movement of the straw feed device is synchronized with the movement of the press carriage, so that, for example, straw is conveyed to the storage point between the press chamber and the retracted press carriage at every retracted position.If necessary, it may also be useful to convey straw to the storage point not at every withdrawn starting position, but only at every second, every third, etc. withdrawn starting position.
[0035] During operation of the baling machine, it may be advisable to fill only one of the two opposing baling chambers with straw. However, it is also possible to fill both baling chambers with straw simultaneously.
[0036] The drive unit encompassing the press carriages allows the straw in the press chamber to be subjected to a high pressing force. This force is typically between 1 ton and 10 tons, for example, 6.5 tons. A sensor, such as a load cell mounted in or on a wall of the press chamber, can be used to evaluate the pressing force.
[0037] The additional pressing device, which allows for the adjustment of a movable wall within the press chamber, can also be adjusted with a high pressing force in a range between 200 kg and 5 t, for example, 2 t. In this case, it may be advantageous to install sensors in or on the press chamber to determine and monitor the pressing force.
[0038] Advantageously, the drive mechanism for adjusting the two press slides is electrically operated, comprising an electric drive motor. The additional press mechanism for adjusting a chamber wall is expediently hydraulically operated and includes a hydraulic actuator. The ejection mechanism for pushing out finished bales is expediently pneumatically operated. The straw feed mechanism for conveying straw to the storage area in front of the press chamber is advantageously electrically operated and includes at least one electric drive motor, optionally two electric drive motors.
[0039] The drives for the straw feeding device, the drive device, the pressing device and the ejection device can be either electrical, electromechanical, hydraulic or pneumatic.
[0040] The geometry of the press chamber can be variable. In particular, it is possible to adjust the length, width, and / or height of the press chamber depending on the type of bale being produced. Furthermore, it can also be advantageous to design the geometry of the press carriage to be variable.
[0041] Further advantages and practical designs can be found in the additional requirements, the figure description, and the drawings. These show: Fig. 1 a side view, partly in section, of a press device for the production of pressed bales from straw, with two opposing press chambers with a drive device for driving two press slides, each assigned to a press chamber, and with two straw feed devices arranged below the press chambers, Fig. 2 the pressing device in side view without section, Fig. 3 the pressing device without illustration of the straw feed device, with the drive device in a 0° position (retracted basic or starting position), Fig. 4 the press device with the drive unit in a 90° position, in which the press slides are moved towards the press chambers, Fig. 5 the pressing device with the drive unit in a 180° position (advanced pressing position), in which the press slides are adjusted maximally in the direction of the press chambers, Fig. 6 a top view of the press device with two drive units, each having two press slides for two opposing press chambers, Fig. 7 a Fig. 6. Corresponding top view of the press device with identification of the press slides and press chambers belonging to a drive unit, Fig. 8. A front view of the pressing device with an additional upper pressing device for adjusting the upper wall of the pressing chambers and with an ejection device for ejecting finished pressed bales. Fig. 9 a Fig. 8 corresponding representation, but with the upper wall of the press chambers in a lowered position.
[0042] In the figures, identical components are labelled with the same reference symbols.
[0043] The illustrated press 1 is used to produce pressed straw bales, which can be used in wall elements of buildings, particularly for insulation. The pressed straw bales produced by the press 1 can be manufactured from delivered straw material with predetermined dimensions, a desired density, and a specific orientation of the straw stalks.
[0044] The press device 1 comprises a support frame 2, which stands on a frame or on supports 3 and accommodates a total of four press chambers 4, which are in Fig. The press chambers 4 are labeled A, B, C, and D, with two press chambers 4 arranged opposite each other. Each press chamber 4 has one open side. The open sides of opposite press chambers 4 face each other. A drive unit 5 actuates press slides 6 to push straw, which is located at a storage point directly in front of the press chambers 4, into the press chambers 4 and compress it with pressure in each press chamber 4. One press slide 6 is assigned to each press chamber 4.
[0045] Each baling chamber 4 is also assigned a straw feed device 7, which is located on the floor below the support frame 2. The straw feed device 7 gathers straw from a delivery position at floor level and conveys it upwards to the discharge point 8, which is located directly in front of an opening of the baling chamber 4. The straw feed device comprises a motor-driven upfeeder 9 and a curved conveying channel 10, which extends from the delivery position at floor level to the discharge point 8 in front of the baling chamber 4. The upfeeder 9 is motor-driven and connected to the drive via a kinematic mechanism, enabling the upfeeder 9 to move along the curve of the conveying channel 10.
[0046] The drive unit 5 simultaneously drives two opposing press slides 6, as is the case in Fig. Figure 7 is shown with the two double arrows. A total of two drive units 5 are provided for the four press chambers 4, each drive unit 5 comprising two press slides for two opposing press chambers 4. The two drive units 5 can be operated independently of each other. The drive units 5 are located on opposite sides of a central longitudinal axis of the press device 1 and are of identical construction. Each drive unit 5 comprises a rotatably mounted drive pulley 11, which is driven by an electric drive motor 13 via a belt or chain 12.An eccentric device converts the rotary motion of the drive disc 11 into a translational forward and backward movement of the two press slides 6, which are adjustable along the central longitudinal axis of the press device 1 between a retracted starting position and a forward pressing position in which the straw in the press chamber 4 is subjected to a pressing force. The retracted starting position is in . Fig. Figure 3 shows the advanced pressing position in Fig. 5, where Fig. 4 represents an intermediate position between the starting and pressing positions.
[0047] The eccentric device comprises a connecting rod 14 for each press slide 6, wherein the two connecting rods 14 are pivotally coupled at one end to a drive arm 15 rotating with the drive disc 11 and at the other end to the press slide 6. Each connecting rod 14 is associated with a drive arm 15, which is non-rotatably connected to a drive shaft 16. The drive shaft 16 is in turn non-rotatably connected to the drive disc 11 and has the same axis of rotation as the drive disc 11. The drive shaft 16 extends transversely to the press 1, i.e., transversely to the longitudinal center axis of the press 1. The pivot points of the two connecting rods 14 on their respective associated drive arms 15 are offset from each other by 180°, as shown, for example, Fig. 4 can be seen. The offset in the transverse direction - or the axial offset with respect to the axis of rotation of the drive disc and the drive shaft - is particularly due to the Fig. 6 and Fig. 7 can be seen, whereby in Fig. Figure 7 shows the offset with the angled double arrow. Accordingly, the two opposing press chambers 4 are also positioned with a corresponding offset from each other.
[0048] With the aid of the drive unit 5, it is possible, firstly, to ensure a significantly reduced force operation due to the simultaneous adjustment of the two press slides 6 into the advanced pressing position and, during the retraction process, into the retracted starting position. Both connecting rods 14 and the press slides 6 attached to them are at the reversal point between pressing and retraction, and vice versa, at the same instant. Accordingly, while forces do act on the drive shaft 16, the other components of the press device 1, in particular the support frame 2 with the bearings for the drive shaft 16, are largely relieved of dynamic pressing forces and retraction forces.
[0049] It is also advantageous that the drive pulley 11 is as in Fig. 4, represented by the curved arrow, must be driven continuously in only one direction of rotation to achieve the desired continuous translational pressing motion – as shown by the straight arrows in Fig. 4 indicated - as well as carrying out the return movement. However, it is not necessary to reverse the direction of rotation of the drive disc 11.
[0050] The drive shaft 16 for each drive unit 5 has three bearing points 17, 18, 19 along its axial length, as Fig. As can be seen in Figure 6. The two bearing points 17 and 19 are located at the two end faces of the drive shafts 16, whereas the central bearing point 18 is arranged in the middle. The two connecting rods 14, each driving a press slide 6, are located on either side of the central bearing point 18. The bearing point 19 in the middle of the press device has two bearings, each assigned to a drive shaft 16 for each drive unit.
[0051] In Fig. Figure 7, which also shows a top view of the press 1, shows a dividing line 20 between the two double arrows. This line runs along the longitudinal center axis of the press 1 and symbolically separates the two drive units 5. The dividing line 20 passes through the bearing 19, which serves as a bearing for both drive shafts 16.
[0052] The two drive units 5 can be operated independently of each other. Each drive unit 5 is assigned an electric drive motor 13. Due to the independent control, it is possible to operate either only one of the two drive units 5 or both drive units 5 simultaneously.
[0053] During the pressing movement of the press carriages 6 across the open side of the press chambers 4, the walls of the press chambers 4 remain stable and immobile. After completion of the pressing process, the press carriages 6 initially remain in their furthest advanced pressing position, whereupon an upper, movable wall or cover 21 of the press chambers 4 is lowered by means of a hydraulically actuated pressing device 22 ( Fig. 8, Fig. 9) to apply an additional pressing force to the straw bale in the press chamber 4 from another side. Using the press carriages 6, a pressing force in a range between 1 t and 10 t, for example a pressing force of 6.5 t, can be generated and applied to the bale. Via the overhead press device 22, a pressing force in a range between 200 kg and 5 t, for example 2 t, can be applied to the bale from another side by lowering the wall or cover 21. The lowering of the wall or cover 21 is, in comparison to the two Fig. 8 and Fig. 9 to recognize.
[0054] After the straw bales have finished pressing, they can be pushed laterally out of the pressing chambers 4 using a hydraulic ejection device 23. The press carriages 6 remain in the extended pressing position, and the wall or lid 21 remains in the lowered position during the ejection movement. As particularly the Fig. 6, Fig. 7, Fig. 8 to Fig. As can be seen from Figure 9, the ejection device 23 is located in the side area, and there are a total of two such ejection devices 23, each of which is used to remove press balls from two press chambers 4 located on the same side of the press device, which belong to different drive devices 5. Fig. 6 A left-hand ejection device 23 can remove press bales from the two press chambers 4 marked A and C, whereas the right-hand ejection device 23 can eject press bales from the two press chambers 4 marked B and D. To carry out the ejection process, the side walls 24 of the press chambers 4 ( Fig. 8) pulled out or, if necessary, lowered so that an ejection path is cleared up to a collection platform 25 ( Fig. 6, Fig. 7), from which the ejected press bale can be collected for further processing. When the ejection device 23 is activated, a sliding plate 26 ( Fig. 8, Fig. 9), which is located on the inner wall of the press chamber wall nearest to the ejection device 23, is adjusted to eject the press bale.
[0055] Instead of a collection platform, the press bale can be pushed out towards a robot gripper or inserted into a receptacle of a robot gripper.
[0056] The movements of the straw conveying device 7 and the drive devices 5 are coordinated so that, in the retracted position of the press carriages 6, straw is conveyed upwards to the storage point 8, which, during the subsequent pressing movement of the press carriages 6, is conveyed into the chambers 4 and compressed there. The frequency of the press carriages 6 is preferably between one and three movements per second, and, for example, at least two movements per second between the retracted starting position and the advanced pressing position.
[0057] Advantageously, the pressing force is monitored. Suitable sensors are provided for this purpose, which can measure and monitor both the pressing force of the press slides 6 and the pressing force of the upper pressing unit 22.
Claims
Pressing device (1) for producing pressed bales from straw, comprising at least one pressing chamber (4) for receiving straw and a pressing carriage (6) for compressing the straw in the pressing chamber (4), wherein the pressing carriage (6) is adjustable by means of a drive device (5) between a retracted starting position and a forward pressing position in which the straw in the pressing chamber (4) is subjected to a pressing force, wherein, in addition to the pressing carriage (6), a pressing device (22) is assigned to the pressing chamber (4) by means of which a movable wall (21) of the pressing chamber (4) is adjustable with a pressing force, characterized in that the pressing device (1) has an ejection device (23) for ejecting pressed bales from the pressing chamber (4),that the press (1) has at least a first and a second press chamber (4) for receiving straw and that each press chamber (4) is assigned a press slide (6) for compressing the straw in the press chamber (4), wherein each press slide (6) is adjustable between a retracted starting position and a forward press position in which the straw in the press chamber (4) is subjected to a pressing force, and that the two press slides (6) are driven by means of a common drive unit (5) located between the two opposing press chambers (4), that the press (1) has two further press chambers (4), also arranged opposite each other, parallel to the first two opposing press chambers (4), each of which is assigned a press slide (6) and a common, additional drive unit (5),wherein a total of two ejection devices (23) are provided, via which press balls are to be removed from two press chambers (4) located on the same side of the press device (1), which belong to different drive devices (5). Pressing device according to claim 1, characterized in that an upper wall (21) of the press chamber (4) is movably designed and the pressing device (22) is located above the press chamber (4). Pressing device according to claim 1 or 2, characterized in that the pressing device (22) is hydraulically actuated. Pressing device according to one of claims 1 to 3, characterized in that the movable wall (21) of the press chamber (4) is directly adjacent to an open side of the press chamber (4), through which the press slide (6) presses the straw into the press chamber (4). Pressing device according to one of claims 1 to 4, characterized in that the pressing device (1) has a straw supply device (7) for conveying straw to a storage point (8) in front of the pressing chamber (4). Pressing device according to claim 5, characterized in that the straw supply device (7) is arranged below the press chamber (4) and the straw can be conveyed by means of the straw supply device (7) from a lower delivery position upwards to a storage point (8) located in front of the press chamber (4). Pressing device according to one of claims 1 to 6, characterized in that the ejection device (23) acts on a sliding plate (26) which is located on the inside of a wall of the press chamber (4). Pressing device according to one of claims 1 to 7, characterized in that a collection platform (25) is arranged laterally on the pressing device (1), onto which an ejected press bale can be deposited. Pressing device according to one of claims 1 to 8, characterized in that the pressing device (22) is arranged in such a way that the maximum pressing force exerted on the movable wall (21) of the pressing chamber (4) corresponds to a weight in a range between 200 kg and 5 t, for example 2 t. Pressing device according to one of claims 1 to 9, characterized in that the drive device (5) is configured such that the maximum pressing force exerted on the press slide (6) corresponds to a weight in a range between 1 t and 10 t, for example 6.5 t. Method for actuating the pressing device according to one of claims 1 to 10, in which first the drive device (5) is actuated to adjust the press slide (6) and then - after completion of the pressing by the press slide (6) - the pressing device (22).