The present invention relates to a feeder module for a converting machine, such as a rotary printing press or a converting machine configured to print and cut sheets to produce packaging elements. The invention may also relate to a digital printing machine.
Converting machines are used in the production of packaging elements such as flat-packed and folding boxes.
Sometimes, the same converting machine is configured to print, cut and crease, and fold the sheet to form a packaging element.
However, it is also common to use several types of converting machines when producing a packaging element. For instance, a first machine in the form of a printing press will print the sheet, a second machine in the form of a die-cutting machine will shape the sheet to a cut-to-shaped blank (also referred to as a flat-packed box). Alternatively, a folder-gluer converting machine may glue and fold the blank to form a folding box.
A common module for most converting machines is a feeder module. The feeder module comprises a loading surface onto which a stack of sheets or cut-to-shaped blanks can be placed. The feeder is configured to discharge the sheets or blanks one by one into the converting machine at a precise timing.
Some feeder modules comprise a movable loading surface which displaces the stack up and down such that the pile is engaged and disengaged from drive belts or rollers in the feeder. The feeder is further provided with a gauge which only allows one sheet to enter into the converting machine at a time.
The feeder is often provided with a rear bar configured to support part of the stack. Instead of moving the loader surface linearly up and down, a pivoting movement can be provided by applying the lifting force at a position at the rear of the stack.
However, this solution has an effect of lifting the rear ends of the sheets to a position which is higher that the vertical tip of the gauge. This may lead to scratching the top side of the sheets as they are passed under the tip of the gauge.
It is an object of the present invention to alleviate the above-mentioned drawbacks of the prior art.
This object is solved by a feeder module according to claim 1.
According to an aspect of the present invention, there is provided a feeder module for discharging sheets into a converting machine. The feeder module comprises a loading surface configured to receive a stack of sheets, and a movable discharge conveyor comprising a plurality of belt conveyors.
The belt conveyors each comprise an upper contact surface which is in contact with the sheets, and wherein the belt conveyors are configured to move between a discharge position in which the belt conveyors are contacting the lowermost positioned sheet in the stack and discharges said sheet, and a clearing position in which the conveyor belts are located underneath the loading surface
The invention is based on a realization that a more precise discharge of sheets can be provided by a vertical movement of the discharge conveyor.
Within the context of this application, the term “converting machine” includes machines which are only configured to print a sheet substrate and converting machines which further comprise cutting and shaping modules such as rotary die-cutters, slotting modules and folding modules, or flatbed die-cutters.
In an embodiment, each of the belt conveyors is guided by a motorized drive roller and an idle roller, wherein the motorized rollers are mounted to a drive shaft.
In an embodiment, the drive shaft comprises a first drive shaft member and a second drive shaft member, and wherein a first group of belt conveyors are connected to the first drive shaft member and a second group of belt conveyors are connected to the second drive shaft member.
The first and second drive shaft members may be connected to a common motor. The motor may be located under the loading surface and in the center of the loading surface.
Preferably, the belt displacement member is arranged between the drive roller and the idle roller, and wherein the belt displacement member is configured to move the belt conveyor up and down in the vertical direction. Hence, the belt displacement member may be restricted to a vertical displacement. That is without any horizontal displacement component.
In an embodiment, the displacement member is arranged inside a loop formed by the belt conveyor and wherein the displacement member is configured to contact an inner periphery of the belt conveyor.
In an embodiment, belt displacement member comprises an upper displacement surface configured to move the contact surface of the conveyor belt and a lower displacement surface configured to move the return portion of the belt conveyor belt.
In an embodiment, the upper displacement surface is provided with apertures.
Preferably, the upper and lower displacement surfaces are provided with a sliding surface configured to contact the inner periphery of the belt conveyor.
In an embodiment, the belt displacement member is connected to a second drive mechanism, and wherein the second drive mechanism comprises a second motor and a timed mechanism. The timed mechanism may comprise an eccentric drive shaft.
In an embodiment, the feeder module according to the preceding claim, wherein the feeder module comprises a suction box provided with a plurality of suction compartments, and wherein the first and second drive shaft members are located in the suction box, and wherein the suction compartments are symmetrically arranged in relation to a center axis of the loading surface.
The invention will now be described with reference to the appended drawings, in which like features are denoted with the same reference numbers and in which:
General description of a Masterflex, DRO and FFG machines
Referring to the figures and in particular to
As illustrated in
A main operator interface 18 may also be provided in the proximity of the converting machine. The converting machine 1 may also comprise a bundler and a palletizer module.
As illustrated in
The lower feeder assembly 22 comprises a loading surface 24 and a sheet discharge mechanism 26. The loading surface 24 is configured to receive a stack
S of sheets 2 and the sheet discharge mechanism 26 is configured to discharge the sheets 2 one by one into the converting machine 1 in the direction of transportation T. The sheet discharge mechanism 26 comprises a plurality of belt conveyors 30 arranged side by side.
The upper feeder assembly 20 comprises a gauge 32. The gauge 32 has a distal vertical end 32′ which is arranged at distance d1 from the loading surface 24. The distance d1 between the distal vertical end 32′ and the loading surface 24 defines a clearance through which the lowermost positioned sheet 2 in the stack S can pass.
The feeder module 12 further comprises a feeder roll assembly 34. The feed roll assembly 34 is located on a downstream side of the gauge 32 and is configured to grasp each sheet 2 to pull the sheet 2 from the loading surface 24. The feed roll assembly 34 comprises an upper feed roller 35a and a lower feed roller 35b.
As best seen in
The loading surface 24 is a flat surface which is configured to receive stacks S of sheets 2. The loading surface 24 is attached to a chassis of the feeder module. The stack of sheets S can be placed on the loading surface 24 by a loader module 10 as the one described in document EP2408698B1.
As best seen in
As illustrated in
Each belt conveyor 30 is provided with an upper contact surface 52 which is in contact with the bottom surface of the sheets 2 and a return portion 54 which is located vertically below the contact surface 52. The upper contact portion 52 of the belt conveyors 30 is thus exposed to the sheet 2 in the elongated slots 44.
The belts conveyors 30 are movable in unison between a discharge position DP in which the contact surfaces 52 of the belt conveyors 30 are located vertically above the loading surface 24, and a clearing position CP in which the contact surfaces 52 of the belt conveyors 30 are located vertically below the loading surface 24. In the discharge position DP, the lowermost positioned sheet 2 in the stack S is brought into contact with the belt conveyors 30 which drive the sheet 2 forward in the direction of transportation T.
Each belt is mounted onto the belt guiding mechanism 48. The belt guiding mechanism 48 comprises a drive roller 56 and an idle roller 58 around which the belt is mounted. The drive roller 56 and the idle roller 58 are rotatably attached to the chassis of the feeder module 12 in a first bracket 60a and a second bracket 60b.
The drive roller 56 may be connected to a drive shaft 62 which extends through the center of all drive rollers 56. In such a way, all the belt conveyors 30 are driven in unison. Alternatively, as best seen in
The common motor may be located in the center under the loading surface 24. In another variant (non-illustrated), the motor may be located on opposite exterior lateral sides of the loading surface 24.
Hence, the driving connection from the motor 39 and to each respective drive shaft 33a, 33b can be located in the center of the loading surface. Alternatively, in a non-illustrated embodiment, two motors 39 can be provided and the driving connection between each motor 39 and each drive shaft 33a, 33b can be located at an exterior portion of the loading surface 24.
Preferably, the drive roller 56 and the idle roller 58 have the same diameter. In such a way, the trajectory of the belt conveyor is symmetric. The drive roller 56 and the idle roller 58 may be toothed and configured to engage with the inner dented surface of the belt conveyors 30.
As best seen in
The upper and lower displacement surfaces 65a, 65b are parallel to each other. The upper and lower displacement surfaces 65a, 65b may be horizontal. The upper and lower displacement surfaces 65a, 65b are preferably interconnected via at least one vertical member 66a, 66b. Preferably, a first vertical member 66a and a second vertical member 66b are provided. The at least one vertical member 66a, 66b may extend across the loading surface 24 such as to interconnect all upper and lower displacement surfaces 65a, 65b of all belt conveyors 30.
As illustrated in
The displacement mechanism 50 is moved in the vertical direction by a motor 75, a toothed drive roller 74, a pulley 71 and a timed mechanism 76. The timed mechanism may comprise an eccentric shaft 76. A first bracket 78 and a second bracket 80 connected the eccentric shaft 76 to the displacement member 64. As the eccentric shaft 76 rotates, the displacement member 64 moves up and down in the vertical direction V. The belt displacement member 64 is thus connected to a second motor 75, which is separate from the motor 39.
The upper and lower displacement surfaces 65a, 65b are positioned symmetrically with respect to the drive roller 56 and the idle roller 58. The displacement member 64 thus symmetrically supports the upper contact portion 52 and the return portion 54 of the belt conveyor 30. The up and down movement of the displacement member 64 is preferably at the same distance. This makes it possible to have the same variations in the length of the belt conveyors on either side of the displacement member and therefore to limit belt tension variations.
Number | Date | Country | Kind |
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23203599.8 | Oct 2023 | EP | regional |