FEEDER SYSTEM FOR FEEDING A STACK OF FLAT ELEMENTS TO A PROCESSING DEVICE

Abstract

A feeder system for feeding a stack (101) of stackable flat, carton elements to a processing device: A delivery ramp (103) includes a receiving surface (104) on which an edge portion (111) and a center portion (116) of the stack (101) is arrangeable. A transport device (125) includes a supporting platform on which at least a further edge portion (115) of the stack (101) is supportable, wherein the supporting platform is arranged adjacent to the receiving surface (104) such that the further edge portion (115) of the stack (101) may be received. A downholder element (117), adjusts a size of a gap (705) between the downholder element and a supporting platform, such that the further edge portion (115) of the stack (101) is clampable between them. The transport device (125) is movable between the receiving position, at which the stack (101) may be received by the delivery ramp (103), and a hand over position at the processing device such that the stack (101) is movable from the receiving position to the hand over position.

Claims

1. A feeder system for feeding a stack of stackable flat elements, to a processing device, the feeder system comprising a delivery ramp which comprises a receiving surface on which an edge portion and a center portion of the stack may be arranged; a transport device comprising a supporting platform on which at least a further edge portion of the stack may be supported; wherein the supporting platform is arranged adjacent to the receiving surface such that the further edge portion of the stack may be received; a downholder element is arranged for adjusting a size of a gap between the downholder element and the supporting platform, such that the further edge portion of the stack is clampable between the downholder element and the supporting platform; the transport device is configured to be movable along a first direction between the receiving position, at which the stack is received by the delivery ramp, and a hand over position at the processing device, such that the stack is movable from the receiving position to the hand over position; and the first direction is transverse to the delivery ramp, parallel to an edge of the delivery ramp and parallel to the further edge portion of the stack which is locatable on the delivery ramp.

2. A feeder system according to claim 1, wherein the downholder element comprises a clamping bar extending along the further edge portion of the stack.

3. A feeder system according to claim 1, wherein the downholder element is a stamp configured to press a section of the further edge portion of the stack against the supporting platform.

4. A feeder system according to claim 1, wherein the transport device comprises a transport carriage to which the second supporting platform is coupled.

5. A feeder system according to claim 4, further comprising a guiding rail, the transport carriage is coupled to the guiding rail such that the transport carriage is drivable along the guiding rail to the hand over position.

6. A feeder system according to claim 1, further comprising: a carrier element which is arranged between the delivery ramp and the hand over position, and arranged such that a portion of the stack is arranged on the receiving surface which is receivable by the carrier element; and the carrier element is configured to carry the portion of the stack between the delivery ramp and the hand over position.

7. A feeder system according to claim 6, wherein the carrier element is fixed to a ground, carrier element comprises a sliding surface extending between the delivery ramp and the hand over position, and the sliding surface is formed such that the stack is slideable on the sliding surface between the delivery ramp and the hand over position.

8. A feeder system according to claim 6, further comprising a carrier structure, fixed to a ground and including the carrier element, the carrier structure is configured such that the carrier element is movable along the carrier structure between the delivery ramp and the hand over position.

9. A feeder system according to claim 1, further comprising: a hand over device arranged at the hand over position, the hand over device comprises a hand over platform, wherein the hand over platform is formed such that the stack at the hand over position is feedable to the processing device; and the hand over device comprises a further downholder element which is arranged for adjusting a size of a further gap between the further downholder element itself and the hand over platform, such that an edge portion of the stack is clampable between the further downholder element and the hand over platform.

10. A feeder system according to claim 9, wherein the hand over device is movable such that a distance between the supporting platform and the hand over platform is variable so that the hand over platform is movable away from the supporting platform for pulling the further edge portion of the stack from the supporting platform if the further downholder element clamps the further edge portion to the hand over platform.

11. (canceled)

12. A feeder system according to claim 1, further comprising: a portioning system for portioning the stackable flat elements in a stack for a further processing, the portioning system comprising: a stacking section on which flat elements are stackable, the delivery ramp is adjacent to the stacking section such that the stack is pushable from the stacking section to the delivery ramp; and a feeder device for moving the stack and comprising a lifting platform and a pushing, the feeder device is movable along a linear path for pushing the stack to the delivery ramp; the feeder device is further movable along a lifting direction having at least a component that is parallel to the direction of gravity; the feeder device is configured such that the lifting platform is movable partially below the flat elements defining the stack such that an edge portion of the stack is arranged on the lifting platform for being liftable by the lifting platform; and the feeder device is further configured such that the stack is pushable by the pushing platform along the linear path until the stack is arranged on the delivery ramp.

13. A feeding system according to claim 1, further comprising: a transfer system for transferring the stack to a processing device, the transfer system comprising: a first comb structure comprising at least one first supporting platform on which at least a further edge portion of the stack is supportable, wherein the first comb structure is mounted to the delivery ramp; a second comb structure comprising at least one second supporting platform on which at least the further edge portion of the stack is supportable; the second comb structure is configured for supplying the stack to the processing device; the first supporting platform and the second supporting platform are arranged along the first direction, one after another, and are interleaved, such that the further edge portion is supportable on at least one of the first supporting platform and the second supporting platform; and the first comb structure and the second comb structure are independently movable along the lifting direction with respect to each other such that the further edge portion at a leading end of the stack is supportable selectively by the first supporting platform or by the second supporting platform.

14. A feeding system according to claim 13, further comprising: the first comb structure comprises at least two first supporting platforms on which the further edge portion of the of the stack is supportable, the two first supporting platforms are spaced along the first direction such that the second supporting platform is movable along the lifting direction through the space between the two first supporting platforms.

15. A method for feeding a stack of stackable flat elements, to a processing device, the method comprising: arranging an edge portion and a center portion of the stack on a receiving surface of a delivery ramp; arranging at least a further edge portion of the stack on a supporting platform of a transport device, the supporting platform is arranged adjacent to a receiving surface such that the further edge portion of the stack is receivable at a receiving position; clamping the further edge portion of the stack between a downholder element and the supporting platform, the downholder element is arranged for adjusting a size of a gap between the downholder element and the supporting platform, and moving the stack along a first direction from the receiving position to a hand over position by a transport device which is configured to be movable between the receiving position and the hand over position at the processing device, wherein the first direction is parallel to an edge of the delivery ramp and parallel to the further edge portion of the stack which is locatable on the delivery ramp.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The aspects defined above and further aspects of the present invention are apparent from the examples of embodiment to be described hereinafter and are explained with reference to the examples of embodiment. The invention will be described in more detail hereinafter with reference to examples of embodiment but to which the invention is not limited.

[0065] FIG. 1 to FIG. 6 show schematic views of a handling system comprising a portioning device, a transfer system and a feeder system according to exemplary embodiments of the present invention.

[0066] FIG. 7 shows a perspective view of a transfer system according to an exemplary embodiment of the present invention,

[0067] FIG. 8 shows a schematic view of a transfer system according to an exemplary embodiment of the present invention, and

[0068] FIG. 9 shows a schematic view of a transfer system and a hand over system according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0069] The illustrations in the drawings are schematic. It is noted that in different figures similar or identical elements are provided with the same reference signs.

[0070] FIG. 1 to FIG. 6 shows show a handling system comprising a portioning device, a transfer system and a feeder system according to exemplary embodiments of the present invention. In particular, the handling system is shown in FIG. 1 to FIG. 6 in different operational states.

[0071] The portioning system is adapted for portioning carton elements in a stack 101 for further processing. The portioning system comprises a stacking section 102 on which flat elements are stackable and a delivery ramp 103 comprising a receiving surface 104 for receiving the stack 101. The delivery ramp 103 is arranged adjacent to the stacking section 102 in such a way that the stack 101 is pushable from the stacking section 102 to the delivery ramp 103.

[0072] The system further comprises a feeder device 105 comprising a lifting platform 106 and a pushing platform 107, wherein the feeder device 105 is movable along a linear path 108 for pushing the stack 101 to the delivery ramp 103. The feeder device 105 is further movable along a lifting direction 110 having at least a component parallel to the gravity direction. The feeder device 105 is configured such that the lifting platform 106 is movable partially below the flat elements defining the stack 101 such that the stack 101 is arranged on the lifting platform 106 for being liftable by the lifting platform 106. The feeder device 105 is further configured such that the stack 101 is pushable by the pushing platform 107 along the linear path 108 until the stack 101 is arranged on the delivery ramp 103.

[0073] The edge portion 111 of the stack 101 denotes a portion of the stack 101 which is in contact with the lifting platform 106. The edge portion 111 is between an edge and a center portion 116 of the stack 101 within a plane along which the length and the width of the stack 101 are defined. The further edge portion 115 is a portion of the stack 101 which is defined between a further edge and a center portion 116, which further edge is an opposite further edge with respect to the edge along the linear path 108.

[0074] The stacking section 102 comprises for example an area on which the flat elements are placed and hence stacked. For example, the flat elements arrive from the manufacturing side and are arranged on a palette (i.e. a Europalette). When they are on such a palette, the flat elements are stacked and form atall tower which may comprise a height of 2 meters and more.

[0075] The receiving surface 104 of the delivery ramp 103 is arranged and formed for receiving the stack 101, which is separated from a lower stack 119 of the flat elements which stack 119 is left within the stacking section 102. The receiving surface 104 has a predetermined height and forms a plateau, which comprises a similar height from the ground or a slightly lower height than the bottom of the stack 101. The bottom of the stack 101 is formed by the lowermost flat element of the stack 101. In particular, the height of the receiving surface 104 is slightly lower than the bottom of the stack 101, if the stack 101 is still arranged within the stacking section 102, but is slightly higher than the height of the topmost flat element of the lower stack 119 which rests within the stacking section 102. Hence, the stack 101 may be simply pushed along a horizontal direction from the stacking section 102 on the receiving surface 104, because the height of the receiving surface 104 and the height of the bottom of the stack 101 is almost similar.

[0076] The stack 101 rests after its portioning from the lower stack 119, which rests in the stacking section 102, on the receiving surface 104 (see FIG. 5 and FIG. 6) and may be used for the further processing, for example to deliver the stack 101 to a desired location at a processing unit, such as a printing machine.

[0077] The feeder device 105 is adapted for separating the stack 101 from the lower stack 119 by lifting and pushing the stack 101 from the stacking section 102 to the delivery ramp 103. Specifically, the feeder device 105 comprises a lifting platform 106 which is configured for lifting the flat elements defining the stack 101. The lifting platform 106 defines a platform which comprises a sufficient large supporting surface on which at least the edge portion 111 of the stack 101 may be arranged. Hence, by the lifting of the lifting platform 106, the edge portion 111 of the stack 101 is lifted such that at least the edge portion 111 and also a part of an adjacent center section 116 of the stack 101 is lifted from the lower stack 119. A further edge portion 115 of the stack 101, which is located at an opposite side of the stack 101 in comparison to the lifted edge portion 111, is still arranged on the topmost flat element of the lower stack 119.

[0078] This has the technical effect that the frictional contact between the lowermost flat element of the stack 101 and the topmost flat element of the lower stack 119 is reduced, making sliding of the stack 101 with respect to the lower stack 119 easier. In particular, the lifting platform 106 is formed and arranged generally within a horizontal plane, such that the weight of the stack 101 may be transferred to the lifting platform 106.

[0079] Furthermore, the feeder device 105 comprises the pushing platform 107 which is configured for pushing the stack 101 along a linear path 108 from the stacking section 102 to the receiving surface 104. The pushing platform 107 defines a platform which is sufficiently large that the stack 101 may be pushed along the linear path 108 without damaging the flat elements of the stack 101. In particular, the pushing platform 107 is formed generally within a vertical plane such that a pushing force is exertable along a horizontal direction by moving the pushing platform 107 along the linear path 108. In particular, the pushing platform 107 is configured, such that the pushing platform 107 may be guided against a lateral surface of the stack 101. In particular, the pushing platform 107 is formed to push the platform 107 in particular against the lowermost flat element of the stack 101. However, the pushing platform 107 may extend from the lowermost flat element of the stack 101 to the topmost flat element of the stack 101 to provide a proper transfer of the pushing force to the stack 101.

[0080] The lifting platform 106 and the pushing platform 107 are formed integrally and hence may be moved together such that no relative movement between the lifting platform 106 and the pushing platform 107 is possible.

[0081] The stack 101 is movable along the linear track. Furthermore, the feeder device 105 is also movable specifically along the linear path 108.

[0082] The feeder device 105 may be coupled to a feeder guiding system 120 which comprises for example, a supporting framework. Along the supporting framework, the feeder device 105 may be driven automatically or manually in a remote controlled manner.

[0083] Furthermore, a position of the delivery ramp 103 is adjustable along the vertical direction. Hence, the height of the delivery ramp 103 from the bottom is adjustable. Hence, also the height of the receiving surface 104 is adjustable in its height, so that the height and hence the amount of flat elements in the stack 101 is adjustable by adjusting the height of the receiving surface 104. The higher is the receiving surface 104, the smaller is the height and the lower is the amount of flat elements of the stack 101 which is adjustable. The lower is the receiving surface 104, the higher is the height and the higher is the amount of flat elements of the stack 101, which is adjustable.

[0084] The receiving surface 104 is formed such that the stack 101 is arrangeable on it by the feeder device 105, wherein at least a section of the receiving surface 104 is formed within a plane which comprises a component parallel to the horizontal direction such that the stack 101 is slidable along the receiving surface 104 due to gravity. In other words, the receiving surface 104 or at least a part of the receiving surface 104 is formed like a ramp having an inclination such that the stack 101 slides due to gravity along the receiving surface 104 to a desired final destination. Hence, no further pushing mechanism along the receiving surface 104 may be necessary.

[0085] In order to improve the sliding of the stack 101 along the receiving surface 104, a vibration system may be arranged to the receiving surface 104 of the delivery ramp 103, such that the receiving surface 104 vibrates. Due to vibrating of the receiving surface 104, sliding of the stack 101 along the receiving surface 104 is supported.

[0086] As shown exemplary in FIG. 2, the delivery ramp 103 comprises a sliding rail 201 arranged on the receiving surface 104. The stack 101 is slideable along the sliding rail 201. The sliding rail 201 is formed such that the stack 101 is pushable on the sliding rail 201 by the pushing platform 107. The sliding rail 201 is a protrusion on the receiving surface 104. The sliding rail 201 extends from an edge of the sliding surface adjacent to the stacking section 102 along the linear path 108 to a section of the receiving surface 104 which defines a desired final destination of the stack 101. By arranging the stack 101 on the sliding rail 201, the contact region of the stack 101 with respect to the receiving surface 104 is reduced so that the friction between the stack 101 and the receiving surface 104 is also reduced such that sliding of the stack 101 along the receiving section is promoted.

[0087] The stacking section 102 comprises a stacking platform 114 on which the flat elements are stackable. The stacking platform 114 is liftable along a vertical direction, i.e. the lifting direction 110.

[0088] Hence, the height of the stacking platform 114 from the bottom is adjustable. Hence, also the height difference with respect to the receiving surface 104 is adjustable, so that the height and hence the amount of flat elements in the stack 101 is adjustable by adjusting the height of the stacking platform 114. The smaller is the height distance between the stacking platform 114 and the receiving surface 104, the higher is the height of the stack 101 to be portioned and the higher is the amount of flat elements of the stack 101. The higher is the height distance between the stacking platform 114 and the receiving surface 104, the lower is the height of the stack 101 to be portioned and the lower is the amount of flat elements of the stack 101.

[0089] Before the step of moving a lifting platform 106 of the feeder device 105 partially below the flat elements defining the stack 101, a further pushing platform 112 is moved along the linear path 108 against a downstream, leading lateral face 113 of the stack 101 such that the stack 101 is pushed along the linear path 108 in the direction to the feeder device 105 such that the edge portion 111 of the stack 101 projects from the lower stack 119 along the linear path 108 and is arrangable on the lifting platform 106. Hence, it is easier to move the lifting platform 106 below the edge portion 111 because the edge portion 111 extends upstream from the lower stack 119. In particular, the further pushing platform 112 is formed such that the further pushing platform 107 is pushing in particular against the lowermost flat element of the stack 101. However, the further pushing platform 903 (FIG. 9) may extend from the lowermost flat element of the stack 101 to the topmost flat element of the stack 101 such that a proper transfer of the pushing force to the stack 101 is provided.

[0090] Furthermore, FIG. 1 to FIG. 6 show a transfer system for transferring the stack 101 to a processing device. The transfer system comprises a first comb structure 121 comprising at least one first supporting platform 123 on which at least the further edge portion 115 of the stack 101 is supportable, wherein the first comb structure is mounted to the delivery ramp 103.

[0091] The transfer system further comprises a second comb structure 122 comprising at least one second supporting platform 124 on which at least the further edge portion 115 of the stack 101 is supportable, wherein the second comb structure 122 is configured for supplying the stack 101 to the processing device. The first supporting platform 123 and the second supporting platform 124 are interleaved with respect to each other such that the further edge portion 115 is supportable on both the first supporting platform 123 and the second supporting platform 124. The first comb structure 121 and the second comb structure 122 are movable with respect to each other such that the further edge portion 115 of the stack 101 is supportable at least by one of the first supporting platform 123 and the second supporting platform 124.

[0092] The first and the second supporting platforms 123, 124 are configured for supporting the flat elements defining the stack 101. Each of the first and the second supporting platforms 123, 124 defines a platform having a sufficiently large supporting surface, on which at least the further edge portion 115 of the stack 101 may be arranged.

[0093] The first supporting platform 123 and the second supporting platform 124 are interleaved with each other. This means that the first supporting platform 123 and the second supporting platform 124 are arranged along a first direction 109 one after another, wherein the first supporting platform 123 and the second supporting platform 124 comprise respective lateral edges which are arranged adjacent to each other along the first direction 109. The first direction 109 describes for example a direction which is parallel to a transverse edge of the delivery ramp 103 and hence parallel to the further transverse edge portion 115 of the stack 101 which is located on the delivery ramp 103.

[0094] The first supporting platform 123 is mounted to the delivery ramp 103. Hence, the edge of the stack 101 located on the receiving surface 104′ may be supported by the first supporting platform 123. The second supporting platform 124 is mounted to a mounting structure, such as a mounting bar. The mounting structure and the delivery ramp 103 may be arranged spaced apart from each other, wherein the first supporting platform 123 extends from the delivery ramp 103 to the mounting structure, and the second supporting platform 124 extends from the mounting structure to the delivery ramp 103. Hence, the further edge portion 115 of the stack 101 is arranged in the gap 705 (see FIG. 7) between the mounting structure and the delivery ramp 103 (see FIG. 6). Within the gap 705, the first supporting platform 123 and the second supporting platform 124 are arranged along the first direction 109, wherein dependent on the height of the delivery ramp 103 for the mounting structure, the first or the second support porting platform supports the further edge portion 115.

[0095] The first supporting platform 123 is movable in particular along a vertical direction with respect to the second supporting platform 124 such that if the edge of the stack 101 is supported by the first supporting platform 123, the second supporting platform 124 may be moved against the further edge portion 115 and lifts the further edge portion 115 of the stack 101 away from the first supporting platform 123. Hence, the further edge portion 115 of the stack 101 is arranged on and supported by the second supporting platform 124. Alternatively, the first supporting platform 123 may be lowered (i.e. along the vertical direction), e.g. by lowering the delivery ramp 103, such that the edge of the stack 101 is supported by the second supporting platform 124 if the first supporting platform 123 is moved lower than the second supporting platform 124.

[0096] Hence, the stack 101 is supported by the first system, i.e. the delivery ramp 103, and is transferred to a second system, e.g. the transfer system, in a robust and simple manner. If the further edge portion 115 of the stack 101 is supported by the second supporting platform 124, the second comb structure may be moved together with the stack 101 to a further processing process, for example.

[0097] The transfer system is described more in detail in FIG. 7.

[0098] Furthermore, as shown in FIG. 1 to FIG. 6, a feeder system for feeding the stack 101 to the processing device is illustrated. The feeder system comprises a transport device 125 comprising the at least one second supporting platform 124 as described above. The second supporting platform 124 is arranged adjacent to the receiving surface 104′ such that the further edge portion 115 of the stack 101 is received (see FIG. 6).

[0099] The feeder system further comprises a downholder element 117, wherein the downholder element 117 is arranged for adjusting a size of a gap 705 between the downholder element 117 itself and the second supporting platform 124 such that the further edge portion 115 of the stack 101 is clampable between the downholder element 117 and the supporting platform (see FIG. 6). The transport device 125 is configured to be movable between a receiving position and a hand over position at the processing device such that the stack 101 is movable from the receiving position to the hand over position.

[0100] Hence, by the above described transport system, the further edge portion 115 of the stack 101 is clamped by the downholder element 117 to the second supporting platform 124. The rest of the stack 101 which is not clamped by the downholder element 117 is arranged on the receiving surface 104′ of the delivery ramp 103, for example. By moving the transport device 125 along a desired moving direction, for example the first direction 109, the stack 101 of flat elements slips away from the receiving surface 104′ to the desired location, such as the hand over position.

[0101] The transport device 125 comprises a transport carriage to which the second supporting platform 124 is coupled. The transport carriage is coupled to a guiding rail 118 such that the transport carriage is drivable along the guiding rail 118 to the hand over position.

[0102] In the following, the method for portioning and transferring the stack 101 from the stacking section 102 to the transfer system 125 is summarized in the following:

[0103] In an initial position, the flat elements are arranged in the stacking section 102. Next, the further pushing platform 112 pushes against the further downstream leading edge portion 115 and pushes the stack 101 along the linear path 108 until the upstream, trailing edge portion 111 projects from the lower stack 119 (see FIG. 2).

[0104] Next, the feeder device 105 is moved in a position, where the lifting platform 106 is arranged below the edge portion 111 and the pushing platform 107 contacts a face of the stack 101 (FIG. 3).

[0105] Next, the feeder device 105 is moved in a position where the lifting platform 106 lifts the edge portion 111 and partially the center section 116 of the stack 101 from the lower stack 119. Further, the pushing platform 107 pushes against the lateral face of the upstream edge portion 111 and hence pushes the stack 101 along the linear path 108 in the direction to the receiving surface 104 (see FIG. 1).

[0106] Next, the device 105 pushes the stack 101 along the linear path 108 until the stack 101 is arranged on the receiving surface 104 (see FIG. 4).

[0107] Next, the stack 101 slides along the receiving surface 104 of the delivery ramp 103 until the further edge portion 115 of the stack 101 is arranged on the first supporting platform 123 of the first comp structure 121. The receiving surface 104′ may be inclined such that the stack 101 slides due to its weight from the feeder device 105 along the receiving surface 104′ until the stack 101 is decoupled from the feeder device 105 (see FIG. 5). The first supporting platforms 123 and the second supporting platforms 124 may comprise vertically extending platforms which functions as a stopper such that the movement of the stack 101 along the linear path 108 is limited.

[0108] Next, a portion of the receiving surface 104′, on which the stack 101 is arranged, is movable along the lifting direction 110. Hence, the receiving surface 104′ is lowered until the first supporting platforms 123 are lower than the second supporting platforms 124 of the second comb structure 122. In this position, the further edge portion 115 is fully supported by the second supporting platforms 124 and, completely decoupled from the first supporting platforms 123. In this position of the stack 101, the downholder element 107 clamps the further edge portion 115 against the second supporting platforms 124, such that the stack 101 is movable, for example along the first direction 109 (see FIG. 6).

[0109] In this position shown in FIG. 6, the stack 101 is portioned such that the stack 101 comprises the desired amount of flat elements and hence a desired height. Furthermore, the stack 101 is transferred from the portioning system to the feeder system by the transfer system. Next, as described further below, the feeder system may move the clamped stack 101 along the first direction 109 from the receiving surface 104′ to the hand over position.

[0110] Hence, by the portioning system according to the present invention, the feeder device 105 is driven in the lifting position, where the lifting platform 106 is moved between a lowermost flat element of the stack 101 and an topmost flat element of the lower stack 119. Next, the feeder device 105 lifts the lifting platform 106 along a lifting direction 110 such that the edge portion 111 and, for example, a further part of the center portion 116 of the stack is lifted and hence separated from the topmost flat element of the lower stack. Next, the pushing platform 107 of the feeder device 105 pushes the stack from the lower stack at the stacking section 102 above the receiving surface 104 of the delivery ramp 103.

[0111] FIG. 7 shows a more detailed view of the transfer system for transferring the stack 101 to the processing device and the feeder system for feeding the stack to the processing device.

[0112] The first comb structure 121 comprises a first mounting bar 701 extending along the first direction 109, wherein the first supporting platforms 123 are mounted to the first mounting bar 701, which may be part of the delivery ramp 103, and extend from the first mounting bar 701 along a second direction 703, which is perpendicular to the first direction 109. The second comb structure 122 comprises a second mounting bar 702 extending along the first direction 109, wherein the second mounting bar 702 is spaced apart from the first mounting bar 701 along the second direction 703. The second supporting platforms 124 are mounted to the second mounting bar 702 and extend from the second mounting bar 702 along a third direction 704, which is opposite to the second direction 703.

[0113] Two first supporting platforms 123 are spaced apart from each other (i.e. along the first direction 109) such that a respective one of the second supporting platforms 124 is movable through the space between the two separated first supporting platforms 123. Hence, along the first direction 109, the first supporting platforms 123 and the second supporting platforms 124 are arranged in an alternating interleaved manner.

[0114] The first comb structure 121 is movably supported e.g. by the delivery ramp 103 in such a way that the first comb structure 121 is movable along the lifting direction 110 with respect to the second comb structure 122 such that the first supporting platforms 123 pass the second supporting platforms along the lifting direction 110.

[0115] The downholder element 117 is a clamping bar 706 extending along the further edge portion 115 of the stack 101.

[0116] The downholder element 117 may for example be hinged to the second mounting bar 702. Hence, the downholder element 170 is pivotable between a clamping position, where the clamping bar 706 clamps the further edge portion 115 of the stack 101 against the second supporting platforms 124, and a releasing position, where the clamping bar 706 does not clamp the stack 101 to the second supporting platforms 124.

[0117] The second mounting bar 702 may be movably mounted to a guiding rail 118 such that the second mounting bar 702 is movable together with the clamped stack 101 along the first direction 109.

[0118] FIG. 8 shows a schematic view of the feeder device, wherein the clamping bar 706 is shown in the clamping position where it clamps the further edge portion 115 of the stack 101 against the second supporting platforms 124. The second mounting bar 702 and the stack 101, as shown in FIG. 8, are moved along the first direction 109 in comparison to the position as shown in FIG. 7. Hence, the delivery ramp 103 is already located in the back of the stack 101 and is illustrated in broken lines. Hence, the center portion 116 and the edge portion 111 of the stack 101 already left the receiving surface 104.

[0119] A carrier element 801 is arranged between the delivery ramp 103 and the hand over position, wherein the carrier element 801 is further arranged such that a portion of the stack 101 is arranged on the receiving surface 104′ and is received by the carrier element 801. The carrier element 801 is configured to carry the portion of the stack 101 between the delivery ramp 103 and the hand over position. The carrier element 801 is fixed to a ground, wherein the carrier element 801 comprises a sliding surface extending between the delivery ramp 103 and the hand over position. The sliding surface is formed such that the stack 101 is slideable on the sliding surface between the delivery ramp 103 and the hand over position.

[0120] The carrier element 801 is for example a table or a supporting bar which extends along a desired direction, in particular along the first direction 109. The carrier element 801 is at the same height or a little bit lower with respect to the receiving surface 104, shown in broken lines, such that the portion of the stack 101 which surrounds the edge which is clamped by the downholder element 117 may slip from the receiving surface 104 on the carrier element 801. Hence, a smoother more soft transport of the stack 101 is provided.

[0121] FIG. 9 shows the feeder device and the hand over position. A hand over device 900 is arranged at the hand over position. The hand over device 900 comprises a hand over platform 901, wherein the hand over platform 901 is formed such that at the hand over position the stack 101 is feedable to the processing device. The hand over device 900 comprises a further downholder element 902, wherein the further downholder element 902 is arranged for adjusting a size of a further gap between the further downholder element 902 and the hand over platform 901 such that the edge portion 111 of the stack 101 is clampable between the further downholder element 902 and the hand over platform 901.

[0122] If the second supporting platforms 124 are driven to the hand over position, the edge portion 111 of the stack 101 is arranged on the hand over platform 901. Next, the further downholder element 902 clamps the edge portion 111 against the hand over platform 901. In a next step, the downholder element 117 may release the further edge portion 115 of the stack 101 and the transport device 125 may drive back to the receiving position, where a new further stack 101 may be received. Next, the further downholder element 902 may release the edge portion 111 of the stack 101 and the flat elements forming the stack 101 may be processed in the processing device.

[0123] Additionally, the hand over device 900 is movable e.g. along the linear path such that a distance between the second supporting platform 124 and the hand over platform 901 is variable so that the hand over platform 901 is movable away from the second supporting platform 124 for pulling the further edge portion 115 of the stack 101 from the second supporting platforms 124 if the further downholder element 902 clamps the edge portion 111 to the hand over platform 901.

[0124] Hence, the further edge portion 115 of the stack 101 lays on a feeding platform 904, whereas the edge portion 111 is still clamped by the further downholder element 902. In a next step, the hand over platform 901 is moved along the linear path 108 again in a direction to the second supporting platforms 124 until the further edge portion 115 and hence the stack 101 are arranged in a desired final position on the feeding platform 904. In a final step, the further downholder element 902 releases the edge portion 111 and the hand over platform 901 moves again away from the second supporting platforms 124 such that the further edge portion 115 slips down from the hand over platform 901. Finally, the stack 101 comprising a desired amount of flat elements is arranged at the feeding platform 904 from which the flat elements may be fed to the processing device.

[0125] It should be noted that the term “comprising” does not exclude other elements or steps and “a” or “an” does not exclude a plurality. Also elements described in association with different embodiments may be combined. It should also be noted that reference signs in the claims should not be construed as limiting the scope of the claims.