Apparatus and method for converting a sheet into a continuous strip

Abstract

The present invention relates to an apparatus and method for converting a sheet of elastomeric material into a continuous strip, the apparatus comprising an infeed section providing a sheet with a series of incisions capable of separating the sheet into interconnected zigzag sections to form a continuous strip, the apparatus further comprising a feed section for feeding the sheet in a feed direction along a feed path to the infeed section, the infeed section comprising a first infeed member for feeding the sheet along the feed path at a first infeed speed and a second infeed member downstream of the first infeed member for feeding the sheet along the feed path at a second infeed speed, the apparatus operable in a stretching mode in which the second infeed speed is greater than the first infeed speed.

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for converting a sheet into a continuous strip. [Background technology]

[0002] WO 2017 / 171454 discloses an apparatus and method for converting a sheet into a continuous strip, the sheet having a series of cuts extending in a cut direction across the sheet relative to a longitudinal direction to form a plurality of interconnected sheet segments, the continuous strip having a zigzag portion, the sheet segments being arranged to be pulled apart in a feed direction to form the zigzag portion, the apparatus comprising a separating device having a holding device for holding an upstream sheet portion against a successive downstream sheet portion in the feed direction, and a sensor device for detecting the separation of the downstream sheet portion from the upstream sheet portion. Summary of the Invention

[0003] A disadvantage of the known devices is that the sheets comprise an elastomeric material that may have irregularities in shape, size and / or thickness. In particular, the sheets may have folds and wrinkles. Small folds and wrinkles can be fed through the device without problems, but larger folds and wrinkles, for example when the sheet is at least partially folded back on itself, may block or jam the device. In such cases, the device must be stopped to allow manual intervention and / or removal of the jam.

[0004] SUMMARY OF THE PRESENT EMBODIMENT It is an object of the present invention to provide an apparatus and method for converting sheets into a continuous strip that can reduce equipment downtime as a result of blockages or jams.

[0005] According to a first aspect, the present invention provides an apparatus for converting a sheet of elastomeric material into a continuous strip, the apparatus comprising a cutting section for forming a series of cuts in the sheet capable of separating the sheet into interconnected zigzag sections to form the continuous strip, the apparatus further comprising an infeed section for feeding the sheet in a feed direction along a feed path to the infeed section, the infeed section comprising a first infeed member for feeding the sheet along the feed path at a first infeed speed and a second infeed member downstream of the first infeed member for feeding the sheet along the feed path at a second infeed speed, the apparatus being operable in a stretch mode in which the second infeed speed is greater than the first infeed speed.

[0006] By providing a speed differential between the first and second infeed speeds, the sheet can be stretched between the first and second infeed members. This stretching can reduce, flatten or smooth irregularities such as creases and wrinkles in the sheet, thus reducing the risk of clogging and / or jamming of the device as a result of such irregularities.

[0007] In a preferred embodiment, the device comprises a first drive for driving one of the first and second infeed members, and the device further comprises a transmission between the first and second infeed members for driving the other of the first and second infeed members with a transmission ratio such that the second infeed speed is greater than the first infeed speed, so that only one of the infeed members needs to be driven.

[0008] Alternatively, the apparatus comprises a first drive for driving the first infeed member, a second drive for driving the second infeed member, and a control unit operatively connected to the first and second drives for controlling the second infeed speed to be higher than the first infeed speed in the stretching mode, by controlling both drives a variable ratio between the first and second infeed speeds can be set and / or adjusted during the stretching mode or can be switched to a non-stretching mode in which the infeed speeds are equal.

[0009] In another embodiment, the first infeed member comprises a first driven roll and a first drive for rotating the first driven roll, the apparatus comprising a control unit operatively connected to the first drive for rotating the first driven roll at a peripheral speed corresponding to the first infeed speed in the stretching mode. The rotation of the first driven roll can be directly or indirectly imparted or transmitted to the sheet to move the sheet at the first infeed speed.

[0010] Preferably, the first infeed member comprises a conveyor belt for transporting the sheet along the feed path and the first driven roll is arranged to drive the conveyor belt. The first infeed member may, for example, be a head or tail pulley for driving the conveyor belt.

[0011] More preferably, the apparatus further comprises a pressing member for pressing the sheet on the conveyor belt in a pressing direction. The pressing can increase friction between the sheet and the conveyor belt and prevent the sheet from slipping relative to the conveyor belt. Thus, the first infeed speed can be reliably imposed on the sheet.

[0012] More preferably, the pressing direction is a vertical direction, and the pressing member is freely movable in the pressing direction under the influence of gravity. Therefore, the pressing force can be applied to the sheet by utilizing the weight of the pressing member. In other words, no driving unit is required to drive the pressing member.

[0013] In a further embodiment, the pressing member comprises a pressing roll which is capable of rolling over the sheet as it is advanced and / or transported along the feed path.

[0014] In another embodiment, the second infeed member comprises a second driven roll arranged to rotate in the stretching mode at a peripheral speed corresponding to the second infeed speed, the rotation of the second driven roll being directly or indirectly imparted or transmitted to the sheet to move the sheet at the second infeed speed.

[0015] In another embodiment, the second infeed member comprises a pair of calender rolls defining an entrance nip for receiving the sheet in the feed direction and an exit nip for further advancing the sheet in the feed direction along the feed path, the pair of calender rolls can further flatten and / or smooth irregularities in the sheet before the sheet reaches a notch.

[0016] It should be noted that the aspect of the pair of calender rolls, and any of the embodiments related to said pair of calender rolls described below, can also be applied independently of the apparatus, and more particularly, independently of any of the aforementioned infeed speeds.

[0017] In particular, in one embodiment of the pair of calender rolls, at least one of the pair of calender rolls is driven, which can pull or feed the sheet further along the feed path towards the incision.

[0018] In another embodiment thereof, one of the pair of calender rolls is rotatable about a first roll axis and is movable toward or away from the other of the pair of calender rolls along a calender direction perpendicular to the first roll axis. By moving one calender roll toward the other calender roll, the pair of calender rolls can be placed in a position to calender the sheet. More specifically, the distance between the pair of calender rolls can be adjusted and / or the pressure exerted by the pair of calender rolls on the sheet can be controlled. By moving one calender roll away from the other calender roll, an opening between the pair of calender rolls can be opened to allow removal or insertion of a sheet, for example during start-up or maintenance of the machine.

[0019] Preferably, the device comprises an actuator for pressing the one calender roll towards the other calender roll along the calender direction, which actuator can be used, for example, to apply a predetermined, variable or constant pressing force to the sheet.

[0020] More preferably, the actuator is further arranged to move the one calender roll away from the other calender roll, the actuator may for example be bidirectionally movable, once the one calender roll is moved away the pair of calender rolls becomes accessible for removal or insertion of sheets.

[0021] In a further embodiment, the pair of calender rolls comprises a first calender roll arranged coaxially with the first roll axis and having a plurality of first disks rotatable about the first roll axis, and the second feed member comprises one or more first guide bodies interposed between the plurality of first disks in an axial direction parallel to the first roll axis, the one or more first guide bodies protruding into a guide region downstream of the advancing nip of the pair of calender rolls. The sheet contains an elastomer material that easily adheres to the circumferential surface of the first calender roll when the pair of calender rolls are at the position of the advancing nip. By providing one or more first guide bodies in the region of the advancing nip, it is possible to prevent the sheet from being pulled along the circumferential surface of the first calender roll. The one or more first guide bodies can force the sheet to continue along the feed path. In particular, the one or more first guide bodies can function as scrapers that scrape the sheet from the circumferential surface of the first calender roll in the advancing nip.

[0022] In one embodiment, the one or more first guide bodies protrude beyond the first discs into a square area including a quadrant of the first discs, the square area extending to the feed path and located downstream of the first roll axis. It is within the square area that there is a risk that the sheet will be pulled along the circumference of the first calender roll. Therefore, by providing one or more first guide bodies within the square area, such pulling can be prevented.

[0023] In another embodiment thereof, each of the one or more first guide bodies comprises a first guide surface for guiding the sheet along the feed path downstream of the first calender roll, the first guide surface being positioned to directly contact the sheet to guide the sheet.

[0024] Preferably, the first guide surface is away from the feed path, which is considered to be in the feed direction. The purpose of the first guide surface is to loosely guide the sheet along the feed path. It is not intended that the first guide surface tightly pinches or presses the sheet. In particular, unnecessary friction between the first guide surface and the sheet should be avoided. Thus, by arranging the first guide surface facing away from the feed path in the feed direction, the first guide surface can be opened or widened with respect to the feeding path, instead of restricting the freedom of movement of the sheet relative to the feed path.

[0025] In another embodiment, the one or more first guide bodies comprise a plurality of first guide bodies, the plurality of first guide bodies being arranged alternately with the plurality of first disks in the axial direction, such that the sheet can be guided along a guide path at the exit nip at two or more positions along the first calender roll.

[0026] In another embodiment, each first disc of the plurality of first discs has a disc width in the axial direction, and each first guide body of the one or more first guide bodies has a guide body width in the axial direction that is smaller than the disc width. The relatively larger disc width allows the first calender roll to apply pressure to the sheet more uniformly, i.e., over a larger contact surface area between the plurality of first discs and the sheet.

[0027] In another embodiment, the one or more first guide bodies are in a retracted position relative to the first disks at the entry nip, such that the first disks can effectively press the sheet at the entry nip while reducing or preventing contact and / or pressure between the sheet and the one or more first guide bodies. In particular, considering that an elastomeric material of the sheet may be slightly pressed into the area between the respective first disks, the one or more first guide bodies may be in a sufficiently retracted position to remain clear of the sheet even when the sheet is slightly pressed against the first calender roll.

[0028] In another embodiment, the one or more first guide bodies are fixed relative to the first roll shaft, and therefore the one or more first guide bodies can be disposed in a fixed orientation relative to the supply path.

[0029] In another embodiment, the apparatus comprises a holder for holding the first calender roll and the one or more first guide bodies, the holder being movable in a calender direction perpendicular to the first roll axis, so that the first calender roll and the one or more first guide bodies can be moved together or integrally by the holder, for example to access the pair of calender rolls for removal or insertion of sheets, or for maintenance.

[0030] In another embodiment, the pair of calender rolls comprises a second calender roll having a plurality of second disks arranged coaxially with a second roll axis parallel to the first roll axis and rotatable about the second roll axis, and the second infeed member comprises one or more second guide bodies interposed between the plurality of second disks in the axial direction, the one or more second guide bodies protruding beyond the plurality of second disks toward the feed path downstream of the second calender roll. The one or more first guide bodies and the one or more second guide bodies can both continue the sheet along the feed path from opposite sides of the feed path.

[0031] In a further embodiment thereof, each first guide body of the one or more first guide bodies faces each second guide body of the one or more second guide bodies in a calendar direction perpendicular to the first roll axis, so that the set of two opposing guide bodies can effectively define a guide channel through which the sheet passes after exiting the pair of calendar rolls.

[0032] In another embodiment thereof, a first guide body of each of the one or more first guide bodies comprises a first guide surface for guiding the sheet along the feed path downstream of the pair of calender rolls, and a second guide body of each of the one or more second guide bodies comprises a second guide surface for guiding the sheet along the feed path downstream of the pair of calender rolls, the first guide surface being spaced apart from the second guide surface considered to be in the feed direction. By arranging the first and second guide surfaces relatively apart in the feed direction, a guide channel defined between the guide surfaces can be opened or widened relative to the feed path, instead of restricting the freedom of movement of the sheet relative to the feed path.

[0033] In another embodiment, which can also be applied independently of the aforementioned infeed members and infeed speeds, the apparatus further comprises an irregularity sensor for detecting irregularities in the sheet upstream of the second infeed member. The irregularity sensor can be used to detect irregularities above a predefined threshold, e.g. irregularities likely to cause problems such as blockages or jams despite measures taken downstream of the irregularity sensor. The apparatus can be stopped to allow for human intervention.

[0034] In another embodiment, which may be applied independently of the aforementioned infeed members and infeed speeds, the infeed section further comprises one or more input rollers for holding the sheet within the device, the one or more input rollers being rotatable in only one direction, so that the one or more input rollers can hold or support the leading edge of the sheet within the device while preventing the leading edge from inadvertently exiting the device in the opposite direction to the feed direction.

[0035] Preferably, the infeed section comprises one or more swing arms for supporting the one or more input rollers relative to the feed path and an irregularity sensor for detecting a parameter indicative of a position and / or orientation of the one or more input rollers or the one or more swing arms relative to the feed path. The one or more swing arms enable the one or more input rollers to be pressed against the sheet by their own weight. When an irregularity occurs in the sheet, the one or more input rollers and the associated one or more swing arms are lifted and the orientation and / or position of these parts can be used to activate the irregularity sensor.

[0036] In another embodiment, the sheet has two longitudinal edges, and a series of the cuts alternately extend from one of the longitudinal edges and terminate at a terminal distance away from the other longitudinal edge to form a plurality of interconnected zigzags, the cuts comprising a cut member for cutting the sheet along a cut line intersecting the feed path, and a lateral edge sensor for detecting a lateral position of the longitudinal edge at a detection position upstream of the cut line relative to the feed direction. The lateral position of the longitudinal edge may vary depending on the original shape of the sheet. The lateral position of the longitudinal edge is detected in order to determine where in the series of cuts to start or end a cut. By detecting the lateral position of the longitudinal edge upstream of the cut line, the start or end position for a future cut can already be determined before the future cut is started.

[0037] In one embodiment thereof, the apparatus is configured to provide a series of said cuts with a cut spacing, and the detection location is upstream of the cut line at a detection distance from the cut line that is equal to or greater than the cut spacing, so that the lateral position of the longitudinal edge can be detected at a detection location associated with a subsequent cut.

[0038] In another embodiment thereof, the lateral edge sensor is arranged to move with the incision member in a cutting direction parallel to the cut line. In particular, the lateral edge sensor can be supported by or relative to a carriage that also carries the incision member. By moving the lateral edge sensor with the incision member, the same lateral edge sensor can be used to detect both longitudinal edges. More particularly, the incision member incises the sheet from a position on the outer side of the sheet aligned with one of the longitudinal edges, so that the lateral position of the one of the longitudinal edges can be detected simultaneously with the incision member incising the sheet at the one of the longitudinal edges.

[0039] Preferably, the lateral edge sensor is arranged centrally relative to the incision member in the incision direction. Since the lateral edge sensor is not used to control the incision in real time, it does not need to detect the lateral position of the longitudinal edge in front of the incision member in the incision direction. Instead, the lateral position of the longitudinal edge can be detected at the current position of the incision member along the incision line. Thus, only a single lateral edge sensor is required, which can be conveniently arranged centrally relative to the incision member and can be used to detect both longitudinal edges in the same way. This can make the device cheaper and / or less complex.

[0040] In a further embodiment, the apparatus further comprises a control unit operatively connected to the lateral edge sensor for receiving a signal indicative of an edge position of one of the longitudinal edges at the detection location, the control unit being configured to associate a signal received from the lateral edge sensor during one of the series of cuts with a future cut to be made in the series. The signal or a value representative of the signal may be stored in a memory for later use, for example, to determine the start or end of the future cut to be made. More particularly, the control unit is configured to set an end distance of the future cut based on the signal from the lateral edge sensor.

[0041] In another embodiment, which may be applied independently of the infeed members and infeed speeds mentioned above, the incision section comprises an incision member for incising the sheet along a incision line intersecting the feed path, the feed path and the incision line extending in a feed plane at their intersection within a range of 0 degrees to 10 degrees relative to a vertical plane. Preferably, the feed plane extends vertically. In a vertical or near vertical direction to the feed plane, gravity can assist in the separation of the interconnected zigzag portions into the continuous strips.

[0042] In another embodiment, which may also be applied independently of the aforementioned infeed members and infeed speeds, the cutting section comprises a cutting member and anvil cooperating to cut the sheet along the cut line intersecting the feed path, the cutting member being movable in a cutting direction perpendicular to the feed path and the cut line to and against the anvil, and the cutting section further comprises a damper for cushioning impacts between the cutting member and the anvil in the cutting direction, the cushioning or damping of the impacts reducing wear on the cutting member as a result of the impacts.

[0043] In another embodiment, the feed path between the first and second infeed members extends within a range of 0 to 30 degrees with respect to the vertical plane, such that irregularities in the sheet can be reduced under the influence of gravity.

[0044] In another embodiment, the device defines a free section of the feed path from the first infeed member to the second infeed member, in which the sheet is not supported, in other words the sheet can extend freely between the respective infeed members, in which irregularities in the sheet can be reduced under the influence of gravity.

[0045] In another embodiment, which may be applied independently of the aforementioned infeed members and infeed speeds, the device comprises an outfeed section having an outfeed opening for outfeeding the continuous strip from the device, the outfeed section further comprising a redirecting member for redirecting the continuous strip towards the outfeed opening. When feeding a new continuous strip through the device, the leading end of the new continuous strip may be in a position that is difficult to reach from outside the device. The redirecting member can be used to conveniently move the leading end at the outfeed opening within reach of a human operator or a mechanical gripper.

[0046] Preferably, the deflection member comprises a manually operable lever which may be located in a safely accessible location, for example on the outside of the device housing.

[0047] According to a second aspect, the present invention provides a method for converting a sheet of elastomeric material into a continuous strip using the apparatus according to any one of the first aspects of the present invention, said method comprising the steps of: feeding the sheet along the feed path by the first infeed member at the first infeed speed; and feeding the sheet along the feed path by the second infeed member at the second infeed speed. Includes.

[0048] The method relates to the practical application of the device according to the first aspect of the invention and therefore has the same technical advantages, which will not be repeated below.

[0049] In one embodiment of the method, the sheet has two longitudinal edges, the series of cuts alternately extending from one of the longitudinal edges and terminating at a terminal distance away from the other of the longitudinal edges to form a plurality of interconnected zigzag portions, the cuts comprising a cut member for cutting the sheet along a cut line that intersects the feed path, and the method further comprising the step of detecting a lateral position of the longitudinal edges at a detection position upstream of the cut line relative to the feed direction.

[0050] Preferably, said series of cuts are provided at a cut spacing and said detection location is upstream of said cut line at a detection distance from said cut line that is equal to or greater than said cut spacing.

[0051] In a further embodiment, the method further comprises a step of associating a lateral position of the longitudinal edge detected at a detection position during one of the series of cuts to a future cut to be made in the series of cuts.

[0052] Preferably, the method further comprises setting an end distance of the future cut based on the lateral position of the longitudinal edge associated with the future cut.

[0053] The various aspects and features described and illustrated in this specification may be applied individually to the extent possible. These individual aspects, in particular those aspects and features described in the accompanying dependent claims, may be the subject of divisional patent applications. [Brief description of the drawings]

[0054] The invention will now be explained on the basis of exemplary embodiments shown in the accompanying schematic drawings. [Figure 1] FIG. 1 is a side view of an apparatus for converting a sheet into a continuous strip according to a first exemplary embodiment of the present invention. [Diagram 2] FIG. 2 is a front view of the device of FIG. [Diagram 3] FIG. 3 is a cross-sectional view of the pair of calender rollers taken along line III-III in FIG. [Figure 4] FIG. 4 is a top view of the pair of calender rollers of FIG. [Diagram 5] 5A and 5B are side views of the notch of the device of FIG. [Figure 6] FIG. 6 is a front view of the notch of FIG. [Figure 7] FIG. 7 is a side view of an alternative apparatus for converting a sheet into a continuous strip according to a second exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0055] 1 and 2 show an apparatus 1 for converting a sheet 8 of elastomeric material, in particular rubber, into a continuous strip 9 according to a first exemplary embodiment of the present invention. The continuous strip 9 is used as input material for an extruder. The sheet 8 is fed to the apparatus 1 as a continuous length. The sheets 8 may be stacked in layers on a pallet. The sheet 8 consists of material that may have irregularities and / or inconsistencies such as folds, wrinkles, thickness variations, irregular edges and / or width variations.

[0056] 2, the sheet 8 comprises a first longitudinal edge 81 and a second longitudinal edge 82. The apparatus 1 comprises a cutout portion 5 adapted, arranged and / or configured to form in the sheet 8 a series of cuts C1, C2, C3, ..., Cn along which the sheet 8 is separable into interconnected zigzag portions 91, 92, 93, 94. In particular, the series of cuts C1, C2, C3, ..., Cn extend alternately from one of the longitudinal edges 81, 82 towards the other and terminate at a terminal distance T away from the other of the longitudinal edges 81, 82 to form the plurality of interconnected zigzag portions 91, 92, 93, 94.

[0057] As best seen in Figure 1, the apparatus 1 includes an infeed section 2 for feeding a sheet 8 along a feed direction F to a cut section 5. The apparatus 1 further includes an outfeed section 6 for feeding a continuous web 9 away from the apparatus 1. The sheet 8 and the continuous web 9 travel along a feed path P, a portion of which is shown in Figure 2. Where the feed path P is not visible in the drawings, e.g. Figure 1, it will be understood that the path along which the sheet 8 and the continuous web 9 travel through the apparatus 1 corresponds to or is coincident with the feed path P.

[0058] 1, the infeed section 2 includes one or more input rollers 21 for holding the sheet 8 in the apparatus 1 when the leading edge of the sheet 8 is fed into the apparatus 1. In this example, the one or more input rollers 21 are rotatable in only one direction to prevent the sheet 8 from sliding back out of the apparatus 1 in the direction opposite to the feed direction F.

[0059] In this exemplary embodiment, the infeed section 2 comprises one or more swing arms 22 for supporting the one or more input rollers 21 relative to the feed path P. The one or more input rollers 21 are free to move under their own weight towards the sheet 8 and come to rest on the sheet 8. Additionally or alternatively, the one or more input rollers 21 may be moved towards or away from the feed path P, for example in an automated or semi-automated manner. Thus, an operator can have at least one hand free to guide the continuous web 9 into the infeed section 2.

[0060] The infeed section further comprises a first infeed member 3 and a second infeed member 4 downstream of the first infeed member 3 in the feed direction F for feeding the sheet 8 along a feed path P towards the incision 5. The first infeed member 3 and the second infeed member 4 are arranged at a distance along the feed path P. In this example, the device 1 defines a free section of the feed path P from the first infeed member 3 to the second infeed member 4, in which the sheet 8 is not supported. In said free section, the feed path P extends at a relatively steep downward angle to the vertical, in particular at an angle in the range of 0 to 30 degrees.

[0061] The first infeed member 3 is adapted, arranged or configured to feed the sheet 8 along the feed path P at a first infeed speed V1. The second infeed member 4 is adapted, arranged or configured to feed the sheet 8 along the feed path P at a second infeed speed V2 different from the first infeed speed V1. The apparatus 1 is operable in a drawing mode in which the second infeed speed V2 is faster than the first infeed speed V1. In particular, the second infeed speed V2 is at least 5% faster, preferably at least 10% faster than the first infeed speed V1.

[0062] The first infeed member 3 comprises a first driven roll 31 adapted, arranged or configured to be driven or rotated at a peripheral speed corresponding to a first infeed speed V1 in the stretching mode. The first driven roll 31 thus imparts the first infeed speed V1 to the sheet 8. In this example, the first driven roll 31 indirectly imparts the first infeed speed V1 to the sheet 8. In particular, the first infeed member 3 further comprises a conveyor belt 32 for conveying the sheet 8 along the feed path P. The first driven roll 31 is one of the pulleys, in particular the head pulley, that drives the conveyor belt 32. The first driven roll 31 is thus able to drive the conveyor belt 32 to operate at the first infeed speed V1.

[0063] In this embodiment, the load carrying side of the conveyor belt 32 extends horizontally or substantially horizontally, i.e., within the range of 0 degrees to 10 degrees relative to the horizontal plane.

[0064] The second infeed member 4 comprises a second driven roll 42 adapted, arranged or configured to be driven or rotated at a peripheral speed corresponding to the second infeed speed V2 in the drawing mode. In this example, the second driven roll 42 is part of a pair of calender rolls 41, 42. The pair of calender rolls 41, 42 comprises a first calender roll 41 and a second calender roll 42. The pair of calender rolls 41, 42 and their related aspects are described in more detail below, but can be claimed independently from the whole apparatus 1. Therefore, in the following, the second driven roll 42 may be referred to as both the "second driven roll" and the "second calender roll", the latter not being limited by the term "driven".

[0065] As shown diagrammatically in FIG. 1, the device 1 comprises a first drive 11 for driving the first driven roll 31 and a transmission 12 between the first driven roll 31 and the second driven roll 42 for driving the second driven roll 42. The transmission 12 may be formed by a chain or a timing belt. Alternatively, gears or other suitable types of transmission may be used. The transmission 12 is configured to obtain a transmission ratio between the first infeed member 3 and the second infeed member 4 such that the second infeed speed V2 is higher than the first infeed speed V1. It will be understood by those skilled in the art that the first drive 11 may alternatively be configured to directly drive the second driven roll 42, in which case the transmission 12 will drive the first driven roll 11.

[0066] The apparatus 1 further comprises a control unit 7 operatively, electronically and / or functionally connected to the first drive 11 for controlling the peripheral speed of the first driven roll 31 in the drawing mode.

[0067] As further shown in FIG. 1, the device 1 comprises a pressing member 23 for pressing the sheet 8 on the conveyor belt 32 in a pressing direction D. In this embodiment, the pressing member 23 comprises a pressing roll 24 that can roll over the sheet 8 as it passes underneath. Furthermore, in this embodiment, the pressing direction D is vertical or substantially vertical. The pressing member 23 is freely movable under the influence of gravity in said pressing direction D, for example in a vertical slot in a frame of the device 1. In other words, the pressing member 23 can be pressed against the sheet 8 by its own weight. In contrast to what is shown in FIG. 1, the pressing member 23 may also be arranged directly opposite the first driven roll 31 or another roller or pulley of the infeed member 3, so as to be able to press the continuous strip 9 more reliably.

[0068] As shown in Figures 1 and 2, the infeed section 2 further comprises one or more infeed guides 27, 28, 29 arranged outside the feed path P, through which the sheet 8 is redirected downwards towards the incision 5 into a free section of said feed path P. As best seen in Figure 1, the one or more infeed guides 27, 28, 29 have an arcuate inner surface capable of redirecting and / or guiding the sheet 8 downwards when the sheet 8 is unable to redirect downwards under its own weight. Furthermore, the one or more infeed guides 27, 28, 29 can reliably limit unpredictable movement of the trailing end of the sheet 8 towards and / or into the incision 5 when the trailing end of the sheet 8 is no longer held and / or controlled by the first infeed member 3.

[0069] As shown in FIG. 1, the first calender roll 41 and the second calender roll 42 are rotatable about a first roll axis R1 and a second roll axis R2, respectively. The roll axes R1, R2 are parallel or substantially parallel to each other. The first calender roll 41 is movable toward and away from the second calender roll 42 in a calender direction X perpendicular to the first roll axis R1. In this embodiment, the infeed section 2 comprises a holder 26 for holding the first calender roll 41 relative to the second calender roll 42. The holder 26 is pivotable about a pivot axis B parallel to and spaced apart from the first roll axis R1 in order to move the first calender roll 41 in the calender direction X.

[0070] In this embodiment, the one or more infeed guides 27, 28, 29 mentioned above form part of and / or are integral with the holder 26. The infeed guides 27, 28, 29 together with the first calender roll 41 can therefore move towards and away from the feed path P about the pivot axis B.

[0071] The device 1 further comprises an actuator 15 for pressing the first calender roll 41 towards the other calender roll 42 in the calender direction X. In this example, the actuator 15 acts on the first calender roll 41 indirectly via a holder 26. The actuator 15 may also be bidirectional, which means that the first calender roll 41 can be moved away from the second calender roll 42, for example to insert and remove the sheets 8 and / or for maintenance purposes.

[0072] The pair of calender rolls 41, 42 is shown in more detail in Figures 3 and 4. In particular, Figure 3 shows that the pair of calender rolls 41, 42 defines an entry nip N1 for receiving the sheet 8 in the feed direction F. The "entry nip" N1 is interpreted as the entrance between the pair of calender rolls 41, 42, where the pair of calender rolls 41, 42 "bites" the sheet 8 as it is moved or pulled through the pair of calender rolls 41, 42. The pair of calender rolls 41, 42 further defines an exit nip N2 for further feeding the sheet 8 along the feed path P in the feed direction F. Similarly, the "entry nip" N1 is interpreted as the exit point between the pair of calender rolls 41, 42, where the sheet 8 exits the pair of calender rolls 41, 42.

[0073] In this embodiment, the feed path P extends vertically or substantially vertically at the exit nip N2, i.e. within a range of 0 to 10 degrees with respect to the vertical plane, as shown in Fig. 3. In particular, a vertical or nearly vertical feed plane Z can be defined at the pair of calender rolls 41, 42, passing through the exit nip N2 and extending in a direction parallel to the feed direction F, the feed path P and / or the first roll axis R1.

[0074] As best shown in FIG. 4, the first calender roll 41 comprises a plurality of first discs 43 arranged coaxially with the first roll axis R1 and rotatable about the first roll axis R1. Similarly, the second calender roll 42 comprises a plurality of second discs 46 arranged coaxially with the second roll axis R2 and rotatable about the second roll axis R2. Furthermore, the first calender roll 41 comprises a plurality of first guide bodies 44 interposed between the plurality of first discs 43 in an axial direction A parallel to the first roll axis R1. Similarly, the second calender roll 42 comprises a plurality of second guide bodies 47 interposed between the plurality of second discs 46 in the axial direction A. In particular, in the axial direction A, the first guide bodies 44 are arranged alternately with the first discs 43, and the second guide bodies 47 are arranged alternately with the second discs 46. It should be noted that in this embodiment, each first guide body 44 is arranged directly opposite a respective one of the second guide bodies 47 in the calender direction X.

[0075] The first guide body 44 is fixed with respect to or adjacent to the first roll axis R1. In other words, the first guide body 44 is arranged to remain stationary while the first disc 43 rotates about said first roll axis R1. In particular, the first guide body 44 is formed as a plate fixed to the holder 26 which holds the first calender roll 41. In this embodiment, the first guide body 44 is U-shaped so that it can be fitted onto the shaft 40 of the first calender roll 41.

[0076] Each disc 43, 46 has a disc width W1 in the axial direction A, and each guide body 44, 47 has a guide body width W2 that is smaller than the disc width W1 in the axial direction A. In particular, the guide body width W2 is less than 80% of the disc width W1, and more preferably less than 60%.

[0077] As shown in FIG. 3, the first guide body 44 protrudes into a guide area G downstream of the exit nip N2 of the pair of calender rolls 41, 42. This guide area G corresponds to and / or overlaps with the remaining space between the calender rolls 41, 42 immediately downstream of the exit nip N2. By providing the first guide body 44 in the guide area G, it is possible to prevent the sheet 8 from being pulled along the circumferential surface of the first calender roll 41. Specifically, the first guide body 44 protrudes beyond the first discs 43 into a square area S including the quadrants Q of the first discs 43. The square area S extends to the feed path P and / or the feed plane Z and is located downstream of the first roll axis R1.

[0078] As further shown in FIG. 3, each first guide body 44 comprises a first guide surface 45 for guiding the sheet 8 along the feed path P downstream of the first calender roll 41. The first guide surface 45 is turned away from or inclined away from the feed path P considered in the feed direction F. In the entry nip N1, the first guide body 44 is in a retracted position relative to the first disc 43. In particular, the first guide surface 45 has an arcuate or circular cross section with a radius smaller than the radius of the first disc 43. Preferably, the first guide body 44 is retracted from the outer periphery of the first disc 43 in the entry nip N1 by a distance of at least 1 millimeter, more preferably at least 2 millimeters.

[0079] The second guide bodies 47 likewise extend from the opposite side of the feed path P and / or the feed plane Z into the aforementioned guide area G. Each second guide body 47 has a second guide surface 48 facing the opposite side of the feed path P and / or the feed plane Z towards the first guide surface 45. The mutually opposing guide surfaces 45, 48 form or define a guide channel for the sheet 8 in the exit nip N2 and can guide said sheet 8 further along the feed path P. In particular, the first guide surface 45 and the second guide surface 48 are spaced apart from each other in the feed direction F. The guide channel formed between the mutually opposing guide surfaces 45, 48 is thus open or widened with respect to the feed path P.

[0080] It should be noted that the first guide body 44 and the second guide body 47 may be identical in shape and / or size and may be interchangeable.

[0081] 5A and 5B show the cutting unit 5 in more detail. As shown in FIG. 6, the cutting unit 5 includes a cutting member 51 for cutting the sheet 8 in a cutting direction C along a cutting line K intersecting the feed path P. In this example, as shown in FIG. 5A, the cutting member 51 is a cutting disk that is rotatable about a cutting axis M parallel to the feed path P, the feed plane Z and / or the feed direction F at the cutting line K. The cutting unit 5 further includes a carriage 50 for moving the cutting member 51 relative to the cutting line K, and a cutting drive unit 54 for driving or moving the carriage 50 in the cutting direction C along the cutting line K.

[0082] The cutting section 5 comprises an anvil 52 which cooperates with the cutting member 51 to cut the sheet 8 along a cutting line K. The anvil 52 is located on the opposite side of the cutting member 51 with respect to the feed path P and / or the feed plane Z. As shown comparatively in Fig. 5A and Fig. 5B, the cutting member 51 is movable to abut against the anvil 52 in a cutting direction H perpendicular to the feed path P, the feed plane Z and / or the cutting line K. The cutting section 5 further comprises a damper 53 for absorbing, cushioning and / or cushioning shocks between the cutting member 51 and the anvil 52 in said cutting direction H. In particular, the cutting member 51 is movable along a cutting stroke in the cutting direction H, and the damper 53 is configured to cushion shocks at the end of the cutting stroke.

[0083] As further shown in Figures 5A and 5B, a feed plane Z at the intersection of the feed path P and the cut line K is vertical or substantially vertical, i.e., within the range of 0 degrees to 10 degrees relative to the vertical.

[0084] As shown in FIG. 1, the delivery section 6 comprises a delivery opening 61 in the housing of the device 1 for delivering the continuous strip 9 from the device 1. Since the feed plane Z in the incision section 5 is vertical or nearly vertical, the leading edge of the continuous strip 9 tends to fall onto the floor surface of the device 1. Therefore, when the incision operation starts and when a new leading edge of the continuous strip 9 occurs, the leading edge must be guided towards and through the delivery opening 61. Since it may be difficult or dangerous to reach into the device 1 during operation, the delivery section 6 further comprises a redirecting member 62 for redirecting the continuous strip 9 towards the delivery opening 61. In this embodiment, the redirecting member 62 comprises a manually operable lever 63. The manually operable lever 63 may be located in a safely accessible position outside the housing of the device 1.

[0085] As shown in FIG. 1, the device 1 further comprises an irregularity sensor 71 for detecting a parameter indicative of the position and / or orientation of the one or more input rollers 21 or the one or more swing arms 22 relative to the feed path P. In particular, the irregularity sensor 71 may be a photocell for detecting a light beam extending on the one or more input rollers 21 and / or the one or more swing arms 22 when the one or more input rollers 21 are in their normal position. However, when the one or more input rollers 21 are displaced by an upward irregularity of the sheet 8, the one or more input rollers 21 or the one or more swing arms 22 associated therewith will interrupt the light beam, which interruption can be used as an indication that the irregularity has passed the position of the one or more input rollers 21. The irregularity sensor 71 is operatively, electronically and / or functionally connected to the control unit 7. Upon receiving a signal from the irregularity sensor 71, the control unit 7 can stop the device 1 and request human intervention.

[0086] The irregularity sensor 71 may alternatively be arranged further downstream of the input roller or rollers 21, for example at a predetermined height above the conveyor belt 32 to directly detect irregularities in the sheet 8, or at the pressing member 23 to detect irregularities as a function of the height of the pressing member 23. The irregularity sensor 71 is arranged upstream of the second infeed member 4 to prevent irregularities above a predetermined threshold from being retained on the pair of calender rolls 41, 42.

[0087] As shown in Fig. 6, the longitudinal edges 81, 82 of the sheet 8 may have a slightly irregular shape. Thus, the lateral positions E1, E2 of each longitudinal edge 81, 82 may vary slightly for each cut C1, C2, C3, ..., Cn in the series of cuts C1, C2, C3, ..., Cn. The apparatus 1 comprises a lateral edge sensor 72 for detecting the lateral positions E1, E2 of the longitudinal edges 81, 82. The detected lateral positions E1, E2 can be used to determine appropriate start, end, cut length and / or termination distance T such that each cut C1, C2, C3, ..., Cn in the series of cuts C1, C2, C3, ..., Cn can end at a position spaced apart from the respective longitudinal edge 81, 82.

[0088] The lateral edge sensor 72 is arranged at a detection position L upstream of the cut line K with respect to the feed direction F. In particular, the device 1 is configured to form the cuts C1, C2, C3, ..., Cn in sequence with a cut spacing I. In other words, the sheet 8 is advanced between the cuts C1, C2, C3, ..., Cn over a distance in the feed direction F equal to the cut spacing I. The detection position L is upstream of the cut line K at a detection distance J from the cut line K equal to the cut spacing I. Alternatively, the detection distance J may be greater than the cut spacing I, and is preferably a multiple of the cut spacing I.

[0089] In this particular embodiment, the lateral edge sensor 72 is arranged to move together with the incising member 51 in the incising direction C. More specifically, the lateral edge sensor 72 is mounted on or carried by the same carriage 50 that carries the incising member 51. The lateral edge sensor 72 is arranged centrally with respect to the incising member 51 in the incising direction C. In other words, the lateral edge sensor 72 is arranged symmetrically with respect to the incising member 51 in the incising direction C. The lateral edge sensor 72 can therefore detect opposite longitudinal edges 81, 82 of the sheet 8 in substantially the same way.

[0090] The lateral edge sensors 72 are operatively, electronically and / or functionally connected to the control unit 7 for transmitting signals indicative of the lateral positions E1, E2 of the respective longitudinal edges 81, 82 to said control unit 7. The control unit 7 is configured to associate a signal received from the lateral edge sensors 72 during a cut C1, C2, C3, ..., Cn of the series of cuts C1, C2, C3, ..., Cn with a future cut C2 of the series of cuts C1, C2, C3, ..., Cn to be made in the future. The signal or a value indicative of said signal may for example be stored in a memory, in particular a non-transient memory, for later use. The control unit 7 is further configured to set an end distance T for said future cut C2 based on the signal from the lateral edge sensors 72.

[0091] As shown in FIG. 1, the device 1 further comprises a first leading edge sensor 73 for detecting when the leading edge of the continuous strip 9 passes the position of the first leading edge sensor 73. In this embodiment, the first leading edge sensor 73 is arranged in the infeed section 2, in particular between the one or more input rollers 21 and the pressing member 23. Alternatively, the function of the first leading edge sensor 73 may be integrated into the one or more input rollers 21 or the pressing member 23. The first leading edge sensor 73 is operatively, functionally and / or electronically connected to the control unit 7 for sending a signal to the control unit 7 indicative of the detection of the leading edge. In this embodiment, the first leading edge sensor 73 comprises a detection roller 74 for rolling on the continuous strip 9. When the leading edge reaches the detection roller 74, it is lifted from the surface of the conveyor belt 32, and this lifting is detected as an indication of the arrival of the leading edge.

[0092] The control unit 7 may further receive a signal from an encoder for tracking how much of the length of the continuous strip 9 has passed the position of the first leading edge sensor 73 in order to theoretically determine when the leading edge reaches the notch 5. In this embodiment, the encoder is coupled to the detection roller 74 for sensing the rotation of the detection roller 74. This has the added technical advantage of being able to more accurately measure the length of the passing continuous strip 9 compared to an encoder associated with the conveyor belt 3, particularly since the detection roller 74 rolls over any waves, wrinkles or folds in the continuous strip 9 and therefore includes in its measurement the length of the continuous strip 9 over the portions with waves, wrinkles or folds.

[0093] It should be noted that a second leading edge sensor 75 may be provided in the cut 5, for example in or opposite the anvil 52, to detect whether the leading edge has actually arrived at the cut 5 as expected. In particular, the second leading edge sensor 75 detects whether the continuous strip 9 is present at the cut line K or whether it is present downstream of the cut line K. If there is a fold or wrinkle that causes the continuous strip 9 to be redirected from its feed path P, the leading edge may not pass through the cut line K. If the leading edge is not detected when, in theory, it should arrive at the cut 5, then it is assumed that something has gone wrong and the apparatus 1 is stopped.

[0094] 7 shows an alternative device 101 according to a second exemplary embodiment of the invention, which differs from the previously described device 1 only in that the transmission 12 is replaced by a second drive 112 controlled by the control unit 7 in conjunction with the first drive 111 such that the second infeed speed V2 is higher than the first infeed speed V1. By supplying the individual drives 111, 112, the ratio between the first infeed speed V1 and the second infeed speed V2 can be adjusted or varied as required.

[0095] The method of converting a sheet 8 of elastomeric material into a continuous strip 9 using the above-described apparatus 1, 101 will now be briefly described with reference to Figures 1-4, 5A, 5B and 6.

[0096] As shown in Figures 1 and 2, the sheet 8 is fed along a feed path P with the first infeed member 3 imparting a first infeed speed V1 to the sheet 8 and the second infeed member 4 imparting a second infeed speed V2 to the sheet 8. By providing a speed difference between the first infeed speed V1 and the second infeed speed V2, the sheet 8 is stretched between the first infeed member 3 and the second infeed member 4. This stretching can reduce, flatten or smooth irregularities such as creases and wrinkles in the sheet 8. Thus, the risk of blockage and / or jamming of the device 1, 101 as a result of such irregularities can be reduced.

[0097] As shown in Figures 5A and 5B, the cutting member 51 is reciprocated in a cutting direction H to form a series of cuts C1, C2, C3, ..., Cn, as best shown in Figure 6. In particular, as shown in Figure 6, the cutting member 51 is positioned outside the sheet 8 in line with the first longitudinal edge 81 and begins a first cut C1 by cutting the sheet 8 through the first longitudinal edge 81. Upon reaching a terminal distance T, the cutting member 51 is pulled back in a direction opposite to the cutting direction H to prevent the cutting member 51 from cutting further into the sheet 8 beyond the terminal distance T. Thus, the first zigzag portion 91 formed by the first cut C1 remains connected to the sheet 8 and any future zigzag portions 92-94 to be cut.

[0098] It is noted that when the cutting member 51 starts the first cut C1, the lateral edge sensor 72 has already detected the lateral position E1 of the first longitudinal edge 81 at a detection position L upstream of the cutting line K. In particular, said lateral position E1 is detected at a position where a future second cut C2 of the series of cuts C1, C2, C3, ..., Cn will be made after completing the first cut C1. The lateral position E1 is used to computationally determine the end distance T of the second cut C2 or a parameter related to said end distance T. Similarly, it is noted that when starting the second cut C2 at the second longitudinal edge 82, the lateral edge sensor 72 can already detect the lateral position E2 of the second longitudinal edge 82 for the purpose of determining or calculating the end distance T of a future third cut C3 of the series of cuts C1, C2, C3, ..., Cn. This process can be repeated for all cuts in the series C1, C2, C3, ..., Cn.

[0099] It should be understood that the above description is included to illustrate the operation of the preferred embodiments and is not intended to limit the scope of the invention. From the above discussion, many variations will be apparent to those skilled in the art that would fall within the scope of the invention. [Explanation of symbols]

[0100] 1 device 11 First drive unit 12. Transmission 2 Supply section 21 Feeding roller 22 Swingarm 23 Pressing member 24 Press roll 25 Actuator 26 Holder 27 First Delivery Guide 28 Second Delivery Guide 29 Third Delivery Guide 3 First feed member 31 First driven roll 32 Conveyor Belt 4 Second feed member 40 Shaft 41 1st Calendar Roll 42 2nd calendar roll / 2nd driven roll 43 Disc 1 44 First guide body 45 First guide surface 46 2nd Disc 47 Second guide body 48 Second guide surface 5 Cutting section 50 Carriage 51 Cutting member 52 Anvil 53 Damper 54 Cutting drive unit 6. Sending section 61 Delivery opening 62 Direction change member 63 Lever 7. Control Unit 71 Irregularity Sensor 72 Lateral Edge Sensor 73 First tip sensor 74 Detection roller 75 Second tip sensor 8 sheets 81 first longitudinal edge 82 second longitudinal edge 9 Continuous strip 101 Alternative Devices 111 First Drive Unit 112 Second Drive Unit A axis direction B Pivot axis C Cutting direction C1 First cut C2 Second cut C3 3rd cut Cn nth cutting depth D Pressing direction E1 Lateral position E2 Lateral position F Supply direction G Guide Area H Cutting direction I Cutting interval J Detection distance K Cut line L Detection position M Cutting axis N1 Entry nip N2 Advance nip P supply route Q Quadrant R1 1st roll axis R2 Second roll axis S square area T termination distance V1 First feed speed V2 2nd feed speed W1 Disc width W2 Guide body width Z supply plane

Claims

1. 1. An apparatus for converting a sheet of elastomeric material into a continuous strip, the apparatus comprising a cutting section for forming a series of cuts in the sheet capable of separating the sheet into interconnected zigzag sections to form the continuous strip, the apparatus further comprising a feed section for feeding the sheet in a feed direction along a feed path to the cut section, the feed section comprising a first infeed member for feeding the sheet along the feed path at a first infeed speed, and a second infeed member downstream of the first infeed member for feeding the sheet along the feed path at a second infeed speed, the apparatus being operable in a stretch mode wherein the second infeed speed is greater than the first infeed speed.

2. 2. The apparatus of claim 1, wherein the apparatus comprises a first drive for driving one of the first and second infeed members, the apparatus further comprising a transmission between the first and second infeed members for driving the other of the first and second infeed members in a transmission ratio such that the second infeed speed is faster than the first infeed speed.

3. 2. The apparatus of claim 1, comprising: a first drive for driving the first feed member; a second drive for driving the second feed member; and a control unit operatively connected to the first drive and the second drive, and configured to control the second feed speed to be faster than the first feed speed in the stretching mode.

4. 2. The apparatus of claim 1, wherein the first infeed member comprises a first driven roll and a first drive for rotating the first driven roll, the apparatus comprising a control unit operatively connected to the first drive to rotate the first driven roll at a peripheral speed corresponding to the first infeed speed in the drawing mode.

5. 5. The apparatus of claim 4, wherein the first infeed member comprises a conveyor belt for transporting the sheet along the feed path, and the first driven roll is positioned to drive the conveyor belt.

6. The apparatus of claim 5 , further comprising a pressing member for pressing the sheet on the conveyor belt in a pressing direction.

7. 7. The device according to claim 6, wherein the pressing direction is vertical, and the pressing member is freely movable in the pressing direction under the influence of gravity.

8. The apparatus of claim 6 , wherein the pressure member comprises a pressure roll.

9. 2. The apparatus of claim 1, wherein the second infeed member comprises a second driven roll, the second driven roll being arranged to rotate in the drawing mode at a peripheral speed corresponding to the second infeed speed.

10. 2. The apparatus of claim 1, wherein the second infeed member comprises a pair of calender rolls defining an entrance nip for receiving the sheet in the feed direction and an exit nip for feeding the sheet further along the feed path in the feed direction.

11. 11. The apparatus of claim 10, wherein at least one of the pair of calender rolls is driven.

12. 11. The apparatus of claim 10, wherein one of the pair of calender rolls is rotatable about a first roll axis and movable toward or away from the other of the pair of calender rolls along a calender direction perpendicular to the first roll axis.

13. 13. The apparatus of claim 12, wherein the apparatus comprises an actuator for urging the one calender roll toward the other calender roll along the calender direction.

14. The apparatus of claim 13 , wherein the actuator is further positioned to move the one calender roll away from the other calender roll.

15. 11. The apparatus according to claim 10, wherein the pair of calender rolls comprises a first calender roll having a plurality of first disks arranged coaxially with a first roll axis and rotatable around the first roll axis, and the second feed member comprises one or more first guide bodies interposed between the plurality of first disks in an axial direction parallel to the first roll axis, the one or more first guide bodies protruding into a guide region downstream of the exit nip of the pair of calender rolls.

16. 16. The apparatus of claim 15, wherein the one or more first guide bodies protrude beyond the plurality of first discs into a square area including a quadrant of the plurality of first discs, the square area extending to the feed path and located downstream of the first roll axis.

17. 16. The apparatus of claim 15, wherein each first guide body of the one or more first guide bodies comprises a first guide surface for guiding the sheet along the feed path downstream of the first calender roll.

18. 18. The apparatus of claim 17, wherein the first guide surface is spaced away from the feed path considered to be in the feed direction.

19. 16. The apparatus of claim 15, wherein the one or more first guide bodies comprise a plurality of first guide bodies, the plurality of first guide bodies being interleaved with the plurality of first disks in the axial direction.

20. 16. The apparatus of claim 15, wherein each first disk of the plurality of first disks has a disk width in the axial direction, and each first guide body of the one or more first guide bodies has a guide body width in the axial direction that is smaller than the disk width.

21. The apparatus of claim 15 , wherein at the entrance nip, the one or more first guide bodies are in a retracted position relative to the plurality of first disks.

22. The apparatus of claim 15 , wherein the one or more first guide bodies are fixed relative to the first roll axis.

23. 16. The apparatus of claim 15, further comprising a holder for holding the first calender roll and the one or more first guide bodies, the holder being movable in a calender direction perpendicular to the first roll axis.

24. 16. The apparatus according to claim 15, wherein the pair of calender rolls comprises a second calender roll having a plurality of second disks arranged coaxially with a second roll axis parallel to the first roll axis and rotatable about the second roll axis, and the second feed member comprises one or more second guide bodies interposed between the plurality of second disks in the axial direction, the one or more second guide bodies protruding beyond the plurality of second disks toward the feed path downstream of the second calender roll.

25. 25. The apparatus of claim 24, wherein each first guide body of the one or more first guide bodies faces each second guide body of the one or more second guide bodies in a calendar direction perpendicular to the first roll axis.

26. 25. The apparatus of claim 24, wherein each of the one or more first guide bodies has a first guide surface for guiding the sheet along the feed path downstream of the pair of calender rolls, and each of the one or more second guide bodies has a second guide surface for guiding the sheet along the feed path downstream of the pair of calender rolls, the first guide surface being spaced apart from the second guide surface considered to be in the feed direction.

27. The apparatus of claim 1 , further comprising an irregularity sensor for detecting irregularities in the sheet upstream of the second infeed member.

28. The apparatus of claim 1 , wherein the infeed section further comprises one or more input rollers for retaining the sheet within the apparatus, the one or more input rollers being rotatable in only one direction.

29. 29. The apparatus of claim 28, wherein the infeed section comprises one or more swing arms for supporting the one or more input rollers relative to the feed path, and an irregularity sensor for detecting a parameter indicative of a position or orientation of the one or more input rollers or the one or more swing arms relative to the feed path.

30. 2. The apparatus of claim 1, wherein the sheet has two longitudinal edges, and the series of cuts alternately extend from one of the longitudinal edges and terminate at a terminal distance away from the other of the longitudinal edges to form a plurality of interconnected zigzags, the cuts comprising a cut member for cutting the sheet along a cut line that intersects the feed path, and a lateral edge sensor for detecting a lateral position of the longitudinal edges at a detection position upstream of the cut line relative to the feed direction.

31. 31. The apparatus of claim 30, wherein the apparatus is configured to provide a series of the cuts with a cut spacing, and the detection location is upstream of the cut line at a detection distance from the cut line that is equal to or greater than the cut spacing.

32. 31. The apparatus of claim 30, wherein the lateral edge sensor is positioned to move with the scoring member in a scoring direction parallel to the score line.

33. 33. The apparatus of claim 32, wherein the lateral edge sensor is centrally located relative to the incision member in the incision direction.

34. 31. The apparatus of claim 30, further comprising a control unit operatively connected to the lateral edge sensor to receive a signal indicative of an edge position of one of the longitudinal edges at the detection location, the control unit configured to associate a signal received from the lateral edge sensor during one of the cuts in the series of cuts with a future cut to be made in the series of cuts.

35. 35. The apparatus of claim 34, wherein the control unit is configured to set the end distance of the future cut based on the signal from the lateral edge sensor.

36. 13. A method for converting a sheet of elastomeric material into a continuous strip using the apparatus of claim 1, comprising the steps of: feeding the sheet along the feed path by the first infeed member at the first infeed speed; and feeding the sheet along the feed path by the second infeed member at the second infeed speed; The method includes:

37. 37. The method of claim 36, wherein the sheet has two longitudinal edges, the series of cuts alternately extending from one of the longitudinal edges and terminating at a terminal distance away from the other of the longitudinal edges to form a plurality of interconnected zigzags, the cuts comprising a cut member for cutting the sheet along a cut line that intersects the feed path, the method further comprising detecting a lateral position of the longitudinal edges at a detection location upstream of the cut line relative to the feed direction.

38. 38. The method of claim 37, wherein the series of cuts are provided at a cut spacing, and the detection location is upstream of the cut line at a detection distance from the cut line that is equal to or greater than the cut spacing.

39. 38. The method of claim 37, further comprising the step of relating a lateral position of a longitudinal edge detected at a detection position during one of the series of cuts to a future cut made in the series of cuts.

40. 40. The method of claim 39, further comprising setting an end distance of the future cut based on the lateral position of the longitudinal edge associated with the future cut.

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