Folding device for folding a cardboard cut-out

Description

[0001] The invention relates to a folding device for folding a carton blank not belonging to the folding device, comprising a folding die unit and a folding head unit, wherein the folding die unit is designed to fold the carton blank around the folding head unit.

[0002] The folding die unit of known folding devices from the applicant comprises a substantially horizontal U-shaped frame on which a plurality of vertically aligned folding tools are arranged. The base leg of the U-shape is mounted on a vertical support of the folding device so that it can be moved up and down in the vertical direction in order to be brought together with the folding head unit for folding the carton blank. The vertical support, in turn, is permanently connected to a machine frame of the machine, in particular a packaging machine, via a cross member.

[0003] In practice, these folding devices have shown that the side legs of the U-shaped form tend to deform not only due to their own weight, but also due to the weight of the folding tools attached to them. In particular, the free ends of the side legs tend to sag slightly downward and / or be deflected by the counterforces exerted on them by the folding head unit during folding and / or by acceleration forces. In extreme cases, this can lead to the carton blank being folded differently at its two ends.

[0004] For further prior art, reference is made to the generic DE 200 19 140 U1, DE 43 23 802 A1, US 2013 / 109555 A1 and ES 2 678 670 B1.

[0005] It is the object of the present invention to remedy this situation.

[0006] This object is achieved according to the invention by a folding device of the type mentioned at the outset, in which the folding die unit comprises two folding die sub-units, each of which has a substantially U-shaped frame on which a plurality of folding tools are arranged, wherein a base leg of the U-shape of each folding die sub-unit is attached to a separate vertical support so as to be movable up and down in the height direction, and wherein the two U-shaped frames are arranged with the openings of the respective U-shapes facing each other.

[0007] In this way, the side legs of the U-shape can be shorter for identical dimensions of the cardboard blanks to be folded, significantly increasing their resistance to deformations caused by gravity and / or counterforces and / or acceleration forces. Overall, the folding device according to the invention results in smaller U-shaped frames than conventional folding devices for folding cardboard blanks of identical dimensions.

[0008] It should already be noted at this point that a U-shaped frame comprises a base leg and two side legs, wherein the side legs can be arranged substantially parallel to one another on the base leg. Furthermore, it should be noted that, in the context of the present invention, a longitudinal direction of the folding device runs substantially parallel to the direction of extension of the undeformed side legs of the U-shape, and a transverse direction of the folding device runs substantially parallel to the direction of extension of the base leg of the U-shape.

[0009] To further reduce the length of the side legs, a predetermined distance can be provided between the free ends of the side legs of the two frames. This makes it possible for the side legs to have a length that is less than half the distance between the two base legs of the U-shaped frames. Since this distance between the two base legs has a direct influence on the maximum longitudinal dimension of the cardboard blanks that can be folded by the folding device, the stability of the side legs can be further increased.

[0010] This measure can also be used to adjust the format range that the folding device can process. For example, if the folding device was originally configured for cardboard blanks with a length ranging from 0 mm to 300 mm, it can easily be converted to a range of, say, 300 mm to 600 mm by, for example, moving one of the folding die subunits on the machine frame by 300 mm, which also increases the distance between the free ends of the side legs of the two frames by 300 mm.

[0011] In order to be able to construct the folding device according to the invention as short as possible in the longitudinal direction despite the provision of two folding die sub-units, at least two drive motors, which are intended to bring about the movement of the frame of at least one of the folding die sub-units in the vertical direction, are arranged at least partially, preferably completely, within the longitudinal extent of the vertical support of the associated folding die sub-unit. Suitable drive motors include motors with a rotating drive shaft, for example electric motors, but also fluidically, in particular pneumatically and / or hydraulically, driven rotary motors, as well as linear motors, for example electromagnetically operating linear motors, but also fluidically, in particular pneumatically and / or hydraulically, driven linear motors, for example pneumatic and / or hydraulic cylinders.

[0012] In motors with a rotating drive shaft, a further development of the invention can provide for the rotational axis of at least one drive motor to be arranged transversely to the longitudinal direction of the folding device. Preferably, each of the folding die subunits is assigned its own transversely arranged drive motor.

[0013] The overall length of the folding device can be further shortened by connecting a cross member, which serves to attach the folding die sub-unit to a machine frame not belonging to the folding device, to the vertical support in at least one of the folding die sub-units, to form a single unit. This eliminates the overall length required for a separate cross member.

[0014] To facilitate format changes, it is proposed that the side legs of at least one folding die sub-unit be adjustable in the transverse direction. The adjustment of the side legs can advantageously be performed synchronously and symmetrically with respect to a longitudinal center plane of the folding device. To enable automated format changes, the adjustment can also be performed by a motor, for example, an electric motor.

[0015] Additionally or alternatively, to facilitate a format change, at least one folding tool of at least one folding die subunit can be designed to be adjustable in the longitudinal direction. To enable an automated format change, the adjustment can advantageously be carried out by a motor, for example, an electric motor.

[0016] In principle, it is also conceivable with the folding device according to the invention for each side leg of the U-frame of the folding die subunits to carry more than one folding tool. However, according to the invention, each side leg of the U-frame of the folding die subunits carries exactly one folding tool. Should engagement of the folding tool with the carton blank be necessary or desired at more than one location, this can be achieved, for example, by having at least one folding tool with more than one engagement section intended for folding engagement with the carton blank.

[0017] The folding device according to the invention allows for various operating modes. The folding device comprises a control device designed to control the drive motors of the two folding die sub-units either synchronously and in the same direction according to a first operating mode or independently of each other according to a second operating mode. The first operating mode corresponds to the normal operation of the folding device. However, with very small cartons, it may be possible for one of the folding die sub-units to fold a carton alone. In In this case, it is possible to operate the folding device in double cycle mode, i.e., to process two carton blanks simultaneously, one in each of the two folding die sub-units. This allows the folding device's capacity to be doubled.

[0018] In order to be able to fold both straight and inclined trays (folding cartons) with the folding device according to the invention, it can further be provided for the first operating mode that the control device is designed to control the drive motors of the two folding die sub-units according to a first sub-operating mode of the first operating mode in order to generate an identical stroke amplitude of the two frames or according to a second sub-operating mode of the first operating mode in order to generate a different stroke amplitude of the two frames.

[0019] To enable easy adjustment of the folding die subunits, a further development of the invention proposes that a cross member have two fastening points at each of its transverse ends, spaced apart from one another in the longitudinal direction and intended for engagement with a machine frame not belonging to the folding device. One of the fastening points is eccentrically designed about a transverse axis. Thus, by simply rotating the eccentrically designed fastening point, the vertical support, for example, can be brought into a position extending exactly vertically.

[0020] Furthermore, the cross member can be connected to the vertical member to form a structural unit.

[0021] The invention will be explained in more detail below using exemplary embodiments with reference to the accompanying drawings.

[0022] It represents: Figure 1 is a perspective view of a folding device according to a first embodiment, Figure 2 is a schematic plan view of the folding device according to the first embodiment, Figure 3 is a side view of the folding device according to Figure 1 illustrated folding device, and Figure 4 is a schematic plan view of a folding device according to a second embodiment.

[0023] In Figure 1 A first embodiment of a folding device is generally designated 100. The folding device 100 is intended for folding a cardboard blank 102.

[0024] For this purpose, the folding device 100 comprises a Figure 3A roughly schematically indicated folding head unit 104 and a folding die unit 106, which is designed to fold the carton blank 102 around the folding head unit 104. According to the invention, the folding die unit 106 comprises two folding die subunits 108, each having a substantially U-shaped frame 110. A plurality of folding tools 112 are arranged on the substantially U-shaped frame 110 of each folding die subunit 108.

[0025] The U-shaped frame 110 comprises a base leg 110a and two side legs 110b, with the side legs 110b extending from the base leg 110a and running substantially parallel to each other. The base leg 110a of the U-shaped form of each folding die subunit 108 is mounted on a vertical support 114 for vertical movement up and down in the vertical direction H.

[0026] At this point it should be noted that the folding device 100 in a longitudinal direction L,a transverse direction Q and the height direction H, which extend orthogonally to each other in pairs. The longitudinal direction L runs essentially parallel to the extension direction of the undeformed side legs 110b and the transverse direction Q runs essentially parallel to the extension direction of the base leg 110a of the U-shaped frame 110, as shown in Figure 2 in the top view of the folding device 100.

[0027] In addition, each of the two substantially U-shaped frames 110 has an opening 110c (see Figure 2 In the folding device 100 according to the invention, the openings 110c of the respective U-shaped portions of the two frames 110 are arranged so that they face each other. As a result, the free ends 110d of the side legs 110b of the frames 110 of the two folding die subunits 108 also face each other.

[0028] In addition, the free ends 110d of the side legs 110b are arranged opposite one another, being spaced apart by a predetermined distance d. This distance d correlates to a minimum distance that the folding tools 112 always maintain during operation. This makes it possible to further reduce the length of the side legs 110b.

[0029] The folding device 100 can also be converted to a different format range by changing the distance d. For this purpose, for example, at least one of the folding die subunits 108 can be moved away from or toward the other folding die subunit 108 in the longitudinal direction L.

[0030] Furthermore, the folding device 100 comprises at least one drive motor 116, which is provided to bring about the movement of the frame 110 of at least one of the folding die sub-units 108 in the vertical direction H. In the illustrated embodiment, each of the folding die sub-units 108 is assigned a separate drive motor 116. The drive motors 116 each have a rotation axis 116a. In the Figures 1 to 3 In the embodiment shown, the rotation axis 116a runs parallel to the longitudinal direction L of the folding device 100.

[0031] Figure 4 shows a folding device 200 according to a second embodiment, which essentially corresponds to the folding device 100 according to the first embodiment. Therefore, in Figure 4 The same components are designated by the same reference numerals as in the Figures 1 to 3, but increased by 100. Furthermore, the folding device 200 will be described below only with regard to its differences from the folding device 100, to whose description express reference is otherwise made here.

[0032] The folding device 200 also has at least one drive motor 216, which is provided to bring about the movement of the U-shaped frame 210 of at least one folding die sub-unit 208 in the vertical direction H. In the folding device 200, each of the folding die sub-units 208 is also assigned a separate drive motor 216. In contrast to the embodiment of the Figures 1 to 3However, the rotation axis 216a of the drive motors 216 runs orthogonally to the longitudinal direction L of the folding device 200, in particular in the transverse direction Q. This configuration can also contribute to keeping the longitudinal extension of the folding device 200 as short as possible. With the same goal in mind, the two drive motors 216 are arranged at least partially within the longitudinal extension of a vertical support 214 of the associated folding die subunit 208. In particular, at least one of the drive motors 216 can be arranged entirely within the longitudinal extension of the vertical support 214.

[0033] With reference again to the Figures 1 to 3 A cross member 118 extends in the transverse direction Q adjacent to a vertical support 114 of a folding die sub-unit 108. The folding die sub-unit 108 is fastened to a machine frame 120 via the cross member 118.

[0034] According to the invention, the cross member 118 can be connected to the vertical member 114 to form a structural unit 122, whereby the overall length of the folding device 100 in the longitudinal direction L can be further shortened. For example, the cross member 118 can be divided into two cross member sections 118a, which accommodate the vertical member 114 between them. Preferably, the two cross member sections 118a are arranged such that the vertical member 114 can be arranged centrally in the transverse direction Q between the two cross member sections 118a and thus centrally in the machine frame 120.

[0035] The vertical support 114 and the cross-support sections 118a can, for example, be welded together. Alternatively, they can also be detachably connected to one another. For this purpose, the assembly 122 can comprise connecting elements 124 by means of which the vertical support 114 is connected to the cross-supports 118. These connecting elements 124 can, for example, be clamping elements tensioned by screws 126, which engage in clamping grooves of the vertical support 114 and the cross-support 118. Such a clamping connection makes it possible to move the vertical support 114 relative to the cross-support 118 in the vertical direction without, for example, having to drill new mounting holes.

[0036] In order to be able to fold carton blanks 102 with different formats, in particular widths, using the same folding device 100 and to facilitate this format change, the side legs 110b of at least one folding die sub-unit 108 are designed to be adjustable in the transverse direction Q, which in Figure 2 is indicated by a dot-dash arrow 128 for a side leg 110b. Figure 2 indicated by a dash-dotted arrow 130 that at least one folding tool 112 can be arranged displaceably in the longitudinal direction L.

[0037] Both the adjustment of a side leg 110b, preferably both side legs 110b, of a U-shaped frame 110 of a folding die sub-unit 108 in the transverse direction Q and the adjustment of a folding tool 112 in the longitudinal direction L on a side leg 110b can be performed by a motor, for example an electric motor. For this purpose, a side leg adjustment unit 132 or a folding tool adjustment unit 134 can be provided (see Figure 3 ). This makes format changes even easier.

[0038] Even though it is fundamentally possible for each side leg to carry more than one folding tool, it is preferred according to the invention that each side leg 110b of the U-shaped frames 110 of the folding die subunits 108 of the first exemplary embodiment discussed carries precisely one folding tool 112, which can extend in the vertical direction H. Each folding tool 112 can have at least one engagement section 112a designed to engage the carton blank 102. However, if engagement of the folding tool 112 with the carton blank 102 is required or desired at more than one location, at least one folding tool 112b can also have more than one engagement section 112a. In Figure 2 The folding tool 112b is provided, for example, with two engagement sections 112a.

[0039] Furthermore, the folding device 100 comprises a control device 136, which in Figure 2is shown only schematically. An analog control device 236 can also be used in the embodiment of the Figure 4 be provided.

[0040] The control device 136 is designed to control the drive motors 116 of the two folding die subunits 108 selectively according to a first operating mode or according to a second operating mode. In the first operating mode, the control device 136 controls the drive motors 116 synchronously and in the same direction, whereas in the second operating mode, the drive motors 116 of the frames 110 of the two folding die subunits 108 are controlled independently of one another. The first operating mode corresponds to the normal operation of the folding device. For very small cartons, however, it may be possible for one of the folding die subunits to fold a carton alone. In this case, it is possible to have the folding device operate in double cycle, i.e., to process two carton blanks simultaneously, one in each of the two folding die subunits. This enables the capacity of the folding device to be doubled.

[0041] Furthermore, the control device 136 can control the drive motors 116 of the two folding die subunits 108 in the first operating mode according to a first sub-operating mode or according to a second sub-operating mode. In the first sub-operating mode of the first operating mode, the control device 136 controls the drive motors 116 of the two folding die subunits 108 such that the frames 110 of the two folding die subunits 108 perform an identical stroke amplitude in the vertical direction H synchronously and in the same direction. In the second sub-operating mode of the first operating mode, the control device 136 controls the drive motors 116 of the two folding die subunits 108 such that the two frames 110 move in the same direction in the vertical direction H, but with different stroke amplitudes. This allows slanted trays to be folded from corresponding cardboard blanks 102 in addition to straight trays.

[0042] During the folding process, the control device 136 controls the drive motors 116 such that the U-shaped frame 110 moves up and down on the vertical support 114 with a preset stroke amplitude in the vertical direction H. Thus, the folding tools 112 provided on the side legs 110b also move in the vertical direction H toward the folding head unit 104 until at least one engagement section 112a engages the carton blank 102. The U-shaped frame 110 then moves further until the predefined stroke amplitude is reached and folds the carton blank around the folding head unit 104 into the desired carton shape. While the U-shaped frame 110 moves away from the folding head unit 104 in the vertical direction H, the folded carton is transported out of the folding device 100 in a known manner, and a new carton blank 102 is fed to the folding device 100.

[0043] For attachment to the associated machine frame 120, the cross member 118 has two attachment points 138 at each of its transverse ends 118b, spaced apart from one another in the longitudinal direction L, which can engage with the machine frame 120 and thus connect the cross member 118 to the machine frame 120. One of the attachment points 138a is eccentric to an axis 140 running in the transverse direction Q. If the two attachment points 138a and 138b engage with the machine frame 120, the eccentrically designed attachment element 138a can be rotated to bring the cross member 118 and / or components attached to it, for example the vertical support 114, into a desired position, for example a precisely vertical position. For easy operation of the eccentrically designed attachment point 138a, a rotating element 142, for example a rotary knob, can be provided on the eccentrically designed attachment point 138a.

Claims

1. Folding device (100; 200) for folding a cardboard blank (102) not belonging to the folding device (100; 200), comprising a folding die unit (106) and a folding head unit (104), wherein the folding die unit (106) is designed to fold the cardboard blank (102) around the folding head unit (104), characterised in thatthe folding die unit (106) comprises two folding die sub-units (108; 208), each of which has a substantially U-shaped frame (110; 210) on which a plurality of folding tools (112) is arranged, the U-shaped frame (110; 210) comprising a base leg (110a) and two side legs (110b); the base leg (110a) of the U-shape of each folding die sub-unit (108; 208) being mounted on a separate vertical support (114; 214) so as to be movable up and down in the vertical direction (H), and wherein the two U-shaped frames (110; 210) are arranged with the openings (110c) of the respective U-shapes facing each other, wherein at least two drive motors (116; 216), which are intended to cause the movement of the frame (110; 210) of at least one of the folding die sub-units (108; 208) in the height direction (H), are arranged at least partially, preferably completely, within the longitudinal extension of the vertical support (114; 214) of the associated folding die sub-unit (108; 208), wherein the folding device (100; 200) comprises a control device (136; 236) which is designed to optionally control the drive motors (116; 216) of the two folding die sub-units (108; 208) synchronously and in the same direction in accordance with a first mode of operation or to control them independently of each other in accordance with a second mode of operation.

2. Folding device according to claim 1, characterised in that a predetermined distance (d) is provided between the free ends (110d) of the side limbs (110b) of the two frames (110).

3. Folding device according to one of the preceding claims, characterised in that the rotation axis (216a) of at least one drive motor (216) is arranged transversely to the longitudinal direction (L) of the folding device (200).

4. Folding device according to one of the preceding claims, characterised in that in at least one of the folding die sub-units (108), a crossbeam (118), which serves to attach the folding die sub-unit (108) to a device frame (120) not belonging to the folding decive (100), is connected with the vertical support (114) to form a construction unit (122).

5. Folding device according to one of the preceding claims, characterised in that the side legs (110b) of at least one folding die sub-unit (108) are designed to be adjustable in the transverse direction (Q).

6. Folding device according to one of the preceding claims, characterised in that at least one folding tool (112) of at least one folding die sub-unit (108) is designed to be adjustable in the longitudinal direction (L).

7. Folding device according to one of the preceding claims, characterised in that each side limb (110b) of the frames (110) of the folding die sub-units (108) carries exactly one folding tool (112).

8. Folding device according to one of the preceding claims, characterised in that at least one folding tool (112b) has more than one engagement section (112a) designated for folding engagement with the cardboard blank (102).

9. Folding device according to one of the preceding claims, characterised in that the control device (136; 236) is designed to control the drive motors (116; 216) of the two folding die sub-units (108; 208) according to a first sub-mode of the first mode of operation to generate an identical stroke amplitude of the two frames (110; 210), or according to a second sub-mode of the first mode of operation to generate a different stroke amplitude of the two frames (110; 210).

10. Folding device according to one of the preceding claims, characterised in that a cross member (118) has, at each of its transverse ends (118b), two fastening points (138a; 138b) which are spaced apart in the longitudinal direction (L) and are intended for engagement with a device frame (120) that does not belong to the folding device (100), wherein one of the fastening points (138a) is designed eccentrically about an axis (140) extending in the transverse direction (Q).