Roll holder for a label roll and label printer

Abstract

The present invention relates to a roll holder for a label roll. This is, in particular, a transversely wound linerless label roll. The roll holder comprises a horizontally arranged axle, which is held on at least one side by a frame. The roll holder includes a rotatable roll receptacle, which is aligned parallel to the axle and mounted on the axle. The roll receptacle is mounted on the axle so as to be linearly displaceable by means of at least one linear bearing. A label printer for printing on a paper tape wound on a label roll comprises a roll holder for the label roll and at least one printhead for printing on the paper tape. A paper path runs along the direction of movement of the paper tape from the roll holder to the printhead. The label printer includes a deflection roller along the paper path, along which the paper tape is guided.

Description

[0001] The present invention relates to a roll holder for a label roll and a label printer, in particular a label printer with a roll holder for a label roll.

[0002] Label printers, in particular label printers for labeling food packaging, comprise a rotatable roll holder designed to support a label roll made from a wound paper tape. During printing, the paper tape is unwound and conveyed along a paper path to a print head. The roll holder comprises, for example, a stop in the axial direction against which the label roll, in particular the core of the label roll, is struck when applied to the roll holder, so that the label roll is in a defined position along the axial direction of the roll holder. If the individual paper layers of the label roll are wound exactly one above the other on the label roll, the edges of the paper tape are always in a predetermined axial position when it is unwound. The taut paper tape is therefore not twisted along the paper path.

[0003] Most common label rolls are rolled so that the edges of the individual paper layers are exactly aligned. The sides of the label roll are aligned along its diameter.

[0004] In the food sector, however, so-called F-wrap or C-wrap packaging is being used more and more. This packaging is marked with a label that is not just on one side of the packaging, but wraps completely around the packaging (F-wrap) or is attached to three sides of the packaging (C-wrap). What these types of packaging have in common is that the label to be applied has an elongated shape, i.e. the extension of the label in one direction is considerably greater, for example four to eight times as large as the extension of the label in the direction perpendicular to it. If the roll width of a label roll with F-wrap or C-wrap labels corresponds to the length of the label, considerably more labels can be wound onto the roll with the same roll diameter than if the roll width corresponds to the short side of the label. A label roll of this type has a roll width of, for example, between 30 cm and 50 cm.For production-related reasons, label rolls of this width, especially linerless label rolls without a backing tape, often cannot be wound up in such a way that the edges of the individual paper layers of the paper tape are aligned. Instead, these label rolls often have an S-shaped profile on their sides, which means that even with axial alignment of the roll core on the roll holder, axial alignment of the side edges of the paper tape cannot automatically be achieved over the entire length of the paper. Instead, with an axially fixed roll core, the side edges of the paper tape move back and forth in the axial direction as the paper tape is unwound. With a defined paper path, this axial movement of the paper tape leads to twisting of the paper tape along the paper path and, in the worst case, to malfunctions of the label printer.

[0005] A device is known from the prior art in which a paper sensor detects an edge of the unrolled portion of the paper tape. Based on the current position of the edge of the paper tape or the direction in which the edge of the paper tape is currently moving, the sensor uses a motor to control the axial position of the roll holder and thus the axial position of the roll core in such a way that the axial displacement of the paper tape on the label roll is compensated. The paper tape is guided safely through the paper path, and no paper twisting occurs. However, such a roll holder is complex and expensive.

[0006] The object of the invention is to find a more cost-effective and less maintenance-prone solution.

[0007] This object is achieved by a roll holder according to claim 1 and a label printer according to claim 14.

[0008] According to the invention, a roll holder for a label roll is proposed. The label roll is, in particular, a linerless label roll, i.e., a label roll without a carrier tape. The label roll is, in particular, rolled up crosswise. This is understood by those skilled in the art to mean a paper strip comprising a plurality of labels applied side by side, a so-called endless strip, wherein the labels lie side by side with the long side in the unwinding direction of the label roll, such that the short side of each label corresponds to the longitudinal direction of the paper strip. The paper strip is provided so that individual labels can be cut from the paper strip using a cutting unit, printed by a label printer before or after cutting, if necessary, and then applied to packaging using a corresponding device, particularly as an F-wrap or C-wrap label.In one embodiment, the width of the label roll, and thus the long side of a label, is between 150 mm and 500 mm. In one embodiment, the short side of the label is between 50 mm and 150 mm long. In one embodiment, the paper tape wound on the label roll is several hundred meters long.

[0009] The roller hanger comprises a horizontally arranged axle supported on at least one side by a frame. In one embodiment, the horizontally arranged axle is supported on one side by a frame, while the other side of the axle is free-floating and thus unsupported.

[0010] The roller holder further comprises a rotatable roller holder, which is aligned parallel to the axis and mounted on the axis. The roller holder is mounted on the axis with at least one linear bearing and can be linearly displaced on the axis via the at least one linear bearing. In one embodiment, two linear bearings are provided, which enable the roller holder to be displaced on the axis, with the two linear bearings being mounted in particular at the axial end regions of the roller holder.

[0011] In this context, a person skilled in the art understands a linear bearing to be a bearing that allows the roller support to be moved along the axis in both axial directions, i.e., forwards and backwards along the axis. The term "linear bearing" does not specify whether the bearing allows or blocks rotation of the roller support on the axis.

[0012] This has the advantage that a label roll, which is held at a defined position on the roll holder, can be moved linearly with respect to the axis. In the case of a label roll whose paper layers have an S-shaped profile in relation to the roll core and thus the individual paper layers have an axial displacement in relation to the roll core, this displacement can be compensated by an opposite displacement of the roll holder, so that twisting of the paper web in the paper path is prevented. This is particularly advantageous for wide label rolls. Since the paper web in the paper path is under tension and the linear bearing enables smooth axial displacement between the axis and the roll holder, the roll holder aligns itself to the corresponding axial position of the paper web due to the paper tension, provided the paper edges are guided or held at a defined position in the paper path.A sensor for detecting the current paper position along the axial direction and a control unit with a motorized actuator for axially moving the roll holder can be omitted.

[0013] In one embodiment, the linear bearing is a plain bearing.

[0014] In one embodiment, the linear bearing is a linear ball bearing, in particular a linear ball bearing with angular misalignment compensation. A linear ball bearing allows linear displacement of the roll holder on the axis with low frictional resistance. This is advantageous because the linear displacement of the roll holder on the axis of the roll holder is achieved by the paper tension of the paper ribbon in the paper path. Smooth linear displacement of the roll holder supports the function of the mechanism. A linear ball bearing with angular misalignment compensation is necessary if the axis bends slightly due to the weight of the label roll. Since the weight of the label rolls is several tens of kg, in particular over 25 kg, slight bending always occurs, especially with an axis that is freely suspended at one end. This bending is compensated for by a linear bearing with angular misalignment compensation.The linear bearing with angular error compensation not only compensates for the bending of the axis but also for misalignment of the housing bores or the axis holder in the housing.

[0015] In one embodiment, the axle is connected to the frame in a rotationally fixed manner. The roll holder is rotatably mounted on the axle. In particular, the at least one linear bearing is a linear ball bearing, which enables both axial and rotational movement of the roll holder on the axle. The axial mobility of the roll holder on the axle by the linear ball bearing compensates for the offset of the individual paper layers transversely to the unwinding direction on the label roll. The linear ball bearing also enables rotational movement of the roll holder on the axle for unwinding the paper tape from the label roll.

[0016] In one embodiment, the axle is rotatably supported by the frame. The roller holder is connected to the axle in a rotationally fixed and linearly movable manner. In one embodiment, the roller holder is connected to the axle in a rotationally fixed manner via a driver, and the driver transfers rotation of the roller holder to the axle. In one embodiment, in the design with a driver, the linear bearing is a linear ball bearing. The driver prevents the roller holder from rotating on the axle, although this rotation would in principle be enabled by the linear ball bearing. However, the linear ball bearing, in particular a linear ball bearing with angular error compensation, has the advantage that tolerances are compensated. The use of a linear ball bearing is therefore also advantageous in this embodiment.

[0017] In one embodiment, the driver consists of a sleeve with a slot running in the axial direction. The sleeve is connected to the axle in a rotationally fixed manner. This also means that the sleeve and the axle are not connected directly, but via an intermediate element. The technical effect is that a rotational movement caused by the sleeve also causes a rotational movement of the axle. A pin connected to the roller holder engages in the slot of the driver. This has the advantage that a rotational movement of the roller holder is transferred to the sleeve with the help of the pin. The rotational movement is transferred to the axle through the rotational connection between the sleeve and the axle.When the label roll located on the roll holder is unwound by exerting a force on the paper tape in the direction of the paper path, a rotational movement is created in the roll holder, which leads to a rotational movement of the axle. At the same time, the design of the sleeve with an axial slot and the rotationally fixed connection between the roll holder and the sleeve, with the pin engaging in the slot, creates a driver that can be moved in the direction of the slot, i.e., in the axial direction. This enables the roll holder to be moved on the axle in the axial direction and simultaneously creates a rotationally fixed connection between the roll holder and the axle.

[0018] In one embodiment, the sleeve of the driver or the axle is connected to a brake disc in a rotationally fixed manner. The brake disc is connected by a band to a deflection roller located in the paper path. In one embodiment, the band is guided around the brake disc so that the brake disc rotates in a loop formed by the band. If the band is tensioned by pulling on the end of the band in a direction away from the brake disc, it exerts a frictional force on the brake disc and brakes the brake disc. In one embodiment, one end of the band is fixed in a fixed position. The other end of the band is fixed to a movable holder for a deflection roller of the paper path. If the tension of the paper band in the paper path decreases, the holder moves and moves the end of the band, thus exerting a braking force on the brake disc. In one embodiment, the band is made of stretchable material.In one embodiment, the band is formed from a flexibly flexible but non-stretchable material, in particular from a sheet metal, in particular a steel sheet, in particular a steel sheet with a thickness between 0.15 mm and 0.45 mm, in particular 0.3 mm.

[0019] In one embodiment, the roller holder consists of a base body, in particular a tubular base body. At least one rail, in particular three rails, which are open in the radial direction, are attached to the base body. The base body is mounted on the axle via the at least one linear bearing for linear movement. The at least one rail guides an at least radially movable clamping element, in particular a clamping plate. In one embodiment, a clamping plate is guided in each rail for radial and axial movement.

[0020] In one embodiment, the roller holder has an operating lever at its axial end. The operating lever can be moved from a working position to an installation position via an eccentric. For the purposes of this disclosure, an eccentric is understood to mean an element that is rotatable about a pivot point, in which the distance between the pivot point and an edge of the element, measured in the horizontal plane, changes when the element is rotated.

[0021] In one embodiment, the operating lever, in the installation position, extends from the roll holder in an extension of the roll holder's axis, i.e., the operating lever is aligned longitudinally in the axial direction of the axis. The at least one clamping plate is adjusted radially by moving the operating lever from the installation position to the working position via the eccentric.

[0022] In one embodiment, the at least one clamping plate comprises a guide rail that runs on a pin in the at least one rail of the base body. The guide rail is arranged such that a movement of the clamping plate in one axial direction of the base body leads to a radial outward displacement of the clamping plate and a movement of the clamping plate in the other axial direction of the base body leads to a radial inward displacement of the clamping plate. In one embodiment, the eccentric and clamping plate interact in such a way that a movement of the operating lever from the installation position to the working position leads to a displacement of the clamping plate in the axial direction, by means of which the clamping plate is guided radially outwards by the guide rail.The eccentric and the clamping plate interact in such a way that a movement of the operating lever from a working position to an installation position leads to a displacement of the clamping plate in the axial direction, by which the clamping plate is guided inwards in the radial direction by the link.

[0023] In one embodiment, an adjusting element is coupled to the operating lever. Rotating the operating lever along or against the direction of rotation of the base body causes the at least one clamping plate to move in the axial direction of the base body. In one embodiment, the adjusting element is positively connected to the operating lever in the direction of rotation of the base body, so that rotating the operating lever causes the adjusting element to rotate. Rotating the adjusting element changes the distance between the base body and the adjusting element. The adjusting element further comprises a driver for the at least one clamping plate, with which the clamping plate is displaced in the axial direction with the adjusting element.

[0024] In one embodiment, the roller holder, in particular the base body, comprises a locking device for locking the roller receptacle in a central position along a displacement path of the roller receptacle on the axis. The central position is not to be interpreted in such a way that the roller receptacle must have an exactly identical travel path in both axial directions from the central position. Rather, the central position is to be understood as meaning that the locking takes place essentially in the middle of the travel path, so that movement in both axial directions is possible after the locking is released. The locking does not lock the roller receptacle in an axial end position.

[0025] According to the invention, a label printer is proposed for printing on a paper tape wound on a label roll. The label printer comprises a roll holder for the label roll and at least one print head for printing on the paper tape. The label printer has a paper path that runs along the direction of movement of the paper tape from the roll holder to the print head. In one embodiment, the paper tape is separated into individual labels by a cutting device between the roll holder and the print head. In this case, too, the paper path is to be understood as the direction of movement from the roll holder to the print head. The label printer comprises a deflection roller along the paper path, along which the paper tape is guided. The deflection roller has the effect that the paper path changes direction at the deflection roller, and the deflection roller guides the paper tape accordingly.The label printer comprises a roll holder in one of the previously described embodiments.

[0026] In one embodiment, the deflection roller comprises a paper guide device. The paper guide device comprises a guide element on each side of the paper strip, wherein the guide elements are adjustable and lockable in the axial direction of the deflection roller. In one embodiment, the guide elements are motor-adjustable. In one embodiment, the guide elements are manually adjustable. In one embodiment, the guide elements are coupled to one another so that adjusting one guide element in one direction leads to adjusting the other guide element in the opposite direction. The guide elements form a guide for the edges of the paper strip. Since the paper strip is under tension at the deflection roller, the axial position of the paper strip on the deflection roller is defined by the guide elements.The axial position of the roll holder follows this position accordingly, so that the paper tape is not twisted when guided between the paper roll and the deflection roll, regardless of whether the top paper layer is offset from the roll core.

[0027] In one embodiment, the deflection roller comprises markings along its axial direction that indicate positions for an arrangement of the guide elements on the deflection roller. The markings are related to the position of the at least one print head and / or the paper width of the label roll. This has the advantage that the markings indicate to the operator the positions of the guide elements to which the guide elements must be adjusted for a certain paper width in order to feed the paper strip to the print head in the correct position for printing in a designated field.

[0028] In one embodiment, the label printer comprises a control device comprising an input device.

[0029] The control device receives at least one paper width of a label roll from the input device. The control device comprises a processor that determines the axial positions of the guide elements on the deflection roller from the received paper width. In one embodiment, the axial positions of the guide elements on the deflection roller are displayed on a display unit. In one embodiment, the processor controls an adjustment unit that motor-drivenly moves the guide elements to the determined axial positions on the deflection roller.

[0030] In one embodiment, the deflection roller is held by a pivoting arm. Pivoting the arm changes the position of the deflection roller and thus the paper path. The arm is preloaded by a spring and the spring pulls the arm in a direction that lengthens the distance along the paper path between the roll holder and the print head. The tension in the paper ribbon pulls the arm in a direction that shortens the distance along the paper path between the roll holder and the print head. The tension in the paper ribbon, or by tightening the paper ribbon, the arm is pulled against the spring force. This has the effect that when the paper ribbon is transported, for example by a transport roller, the paper is tensed and the deflection roller pulls in a direction that shortens the paper path. This enables rapid, jerky acceleration of the paper ribbon. The spring force pulls the arm in the opposite direction.In particular, when the paper tape is not being transported, the spring force outweighs the tension of the paper tape and the arm is pulled in a direction that makes the paper path longer.

[0031] For clarification, it is noted that the expression "distance from the deflection roller to the print head" is for illustrative purposes.

[0032] Due to the paper roll diameter decreasing over printing time and the fact that the top layer of paper from a paper roll is always unwound, the exact paper guide changes depending on the diameter of the paper roll. However, those skilled in the art in the label printing field will be familiar with the interpretation of the term paper path. In one embodiment, the deflection roller defines a deflection point for the paper ribbon in the paper path. The paper ribbon runs with its flat side over the deflection roller. In one embodiment, the paper ribbon runs with its non-adhesive side over the deflection roller. In one embodiment, the paper ribbon runs with its adhesive side over the deflection roller, wherein the deflection roller is provided with an anti-adhesive coating. In one embodiment, the adhesive side of the paper ribbon comprises a plurality of longitudinal strips of adhesive material, wherein the longitudinal strips are narrow compared to the width of the paper ribbon.In one embodiment, the longitudinal strips of adhesive material are interrupted at the points where the paper tape is intended for separating individual labels.

[0033] In one embodiment, the label printer comprises an actuator, in particular a pneumatic cylinder. The actuator moves the arm against the spring force into an installation position. In the installation position, the distance along the paper path between the roll holder and the print head is short. This means that the actuator pushes the arm against the spring force, which, as described above, tensions the paper ribbon. In other words, the actuator pushes the arm into a position in which the paper ribbon, if a paper ribbon is inserted in the paper path, is released. The actuator is triggered by the control device of the label printer. In one embodiment, the control device of the label printer triggers the actuator when a sensor detects the opening of the label printer's cover or when the control device receives a signal from the input device that the label roll should be changed.This has the effect of causing the actuator to move the arm and the idler roller into a position where, after a new label roll has been applied to the roll holder, the paper ribbon can be inserted into the paper path from the roll holder to the print head. Specifically, when the actuator is moved, another actuator creates a gap between a print roller and the print head, or between a transport roller and a counter-holder to the transport roller, allowing the end of the paper ribbon to be inserted into the gap. If the transport roller and counter-holder, or the print roller and print head, and the arm are subsequently returned to their original position, the label printer is ready for operation again.

[0034] In one embodiment, the band which is connected to the brake disc is fastened at one end to the pivoting arm. The band runs over at least part of the circumference of the brake disc. In one embodiment, the band runs in a loop or in part of a loop around the brake disc. The band is tensioned around the brake disc when the pivoting arm moves with the spring force and the band is released around the brake disc when the pivoting arm moves against the spring force. This has the effect that the brake disc and thus the roll holder with the label roll are braked when the paper path becomes longer, i.e. when more paper is unwound from the roll than is processed by the print head. This prevents the paper roll from running on when the transport of the paper tape is stopped.

[0035] In one embodiment, the roll holder, in particular the base body or in particular an end element on the base body, comprises a locking device for locking the roll holder in a central position along a displacement path of the roll holder on the axis. The linear displacement of the roll holder on the axis is prevented by the locking device. This is advantageous for changing the paper roll, as the operator does not have to pay attention to not moving the roll holder into the end position of the axial displacement path when sliding on the paper roll, which would therefore only allow the label roll to be moved in one axial direction. If the roll holder is locked with the locking device, in particular in the middle of the axial displacement path, and remains in this axial position when the paper roll is applied, the roll holder can move in both axial directions during printing operation after the locking device is released.In one embodiment, the locking device is triggered when the sensor for the cover detects the opening of the cover. In one embodiment, the locking device is coupled to the actuator, in particular the pneumatic cylinder of the arm. In one embodiment, the locking device consists of a movable retaining plate that engages a slot in the roll holder.

[0036] Some embodiments of the invention are shown by way of example in the drawings and described below. They show, in schematic representations: Fig. 1 a sectional drawing of a label roll, Fig. 2a a roll holder for a label printer in a first view, Fig. 2b a roll holder for a label printer in a second view, Fig. 3 a deflection roller, Fig. 4 a locking device for a roll holder, Fig. 5a a sectional drawing of a roll holder, Fig. 5b a roll holder, Fig. 6a a driver of a roll holder, Fig. 6b a sleeve for the driver of a roll holder, Fig. 7 an axis of a roll holder, Fig. 8a a roll receptacle of a roll holder in a first view, Fig. 8b a roll receptacle of a roll holder in a second view, Fig. 9a a tensioning device of a roll holder in a first view, Fig. 9b a tensioning device of a roll holder in a second view, and Fig. 9c clamping plates and an adjusting element of the tensioning device.

[0037] Fig. 1 shows a sectional drawing through a label roll 11. The drawing serves to illustrate the effect that the individual paper layers 14a, 14b, 14c are not rolled up flat at the edges, vertically relative to one another. This effect is particularly pronounced when dealing with cross-wound and thus very wide label rolls 11, such as those used for F-wrap labeling. Such a label roll 11 is, for example, up to 50 cm wide. The label roll 11 is wound around a roll core 13. The center point of the roll core 13 defines the axis 12 of the label roll 13, around which the endless tape of the label roll 11 is unwound. The individual paper layers 14a, 14b, 14c of the endless tape are continuously wound onto the label roll 11.The production process causes a horizontal shift of the individual paper layers 14a, 14b, 14c, resulting in bulges 16 and indentations 15 on the left and right vertical edges of the label roll 11. This means that the individual paper layers 14a, 14b, 14c can be shifted horizontally relative to each other. Since the topmost paper layer is always unwound, a vertical shift of the paper strip occurs when the paper strip is unwound from the label roll 11.

[0038] Fig. 2a and 2bshow a roll holder of a label printer for a label roll 11 in two different views. The roll holder comprises a frame which is attached to a labeler, for example an F-Wrap labeler. The frame comprises a vertical support 21, which is continued by a holder 22 for a roll holder 80. The roll holder 80 is rotatably attached to the holder 22 via ball bearings. The roll holder further comprises a tensioning device 70 and a driver device 60. The roll holder comprises a locking device 50 for locking the roll holder 80 in an axial position. The roll holder further comprises a deflection roller 30, which is pivotally mounted via a pivot device 40 and defines the paper band. The pivot device 40 comprises a pivotable arm 41, which is pivotally mounted about a pivot point 42. The deflection roller 30 is rotatably mounted on the pivotable arm 41.The pivoting arm 41 is pulled by the spring force of a spring 46 in a direction 48, in which the paper path defined by the deflection roller 30 between the label roll 11 and the print head becomes longer. When the pneumatic cylinder 45 is extended, a piston 45 of a pneumatic cylinder 44 moves the pivoting arm 41 in an opposite direction 47, in which the paper path defined by the deflection roller 30 between the label roll 11 and the print head becomes shorter. This movement is limited by a stop 49 for the pivoting arm. A fastening mechanism 43 attaches a flexible steel band 62 to the pivoting arm 41, particularly near the pivot point 42, and guides it over a brake disc.

[0039] Fig. 3 shows the deflection roller 30 for the paper tape. The paper tape, which is unwound from the label roll 11, wraps around a rotatable roller 31 of the deflection roller 30. The paper tape comprises a first side edge 12 and a second side edge 13. In order to guide the paper tape in a defined manner in the paper path with regard to its position on the deflection roller 30 perpendicular to the direction of movement of the paper tape, the deflection roller 30 comprises a paper guide device. Attached to the rotatable roller 31 is an axially movable first guide element 32 which can be fixed in an axial position on the rotatable roller 31 by a first fixing device 34. Furthermore, attached to the rotatable roller 31 is an axially movable second guide element 35 which can be fixed in an axial position on the rotatable roller 31 by a second fixing device 37. The side edges 12, 13 of the paper strip slide along the inner sides 33, 36 of the respective guide element 32, 35.If the guide elements 32, 35 are fixed in the axial direction such that the distance between the inner sides 33, 36 of the guide elements 32, 35 corresponds to the width of the paper strip, possibly the width of the paper strip including a small tolerance, the paper strip wraps tightly around the rotatable roller 31 due to the paper tension and is guided in a defined manner. The rotatable roller 31 further comprises markings 38 along its axial direction which indicate positions for an arrangement of the guide elements on the deflection roller. The markings 38 are related to the position of the at least one print head and / or the paper width of the label roll. This means that the markings 38 show an operator at which position in the axial direction the guide elements 32, 35 must be fixed for a specific paper roll 11 with a defined width and a predetermined print field.

[0040] Fig. 4 shows a locking device 50 for a roll holder for locking the roll receptacle 80 in a central position along the axial displacement path of the roll receptacle. The locking device 50 consists of a movable retaining plate 51, which engages with one end 53 in a slot 54 in the roll holder 80, in particular in a slot 54 of an end element 64 of the roll holder 80. The locking device 50 comprises a locking guide 52, which is fixedly connected to the holder 22 of the vertical support 21. The retaining plate 51 is linearly movable in the locking guide 52. The retaining plate 51 is moved into the locking position in the direction of the roll receptacle by a pneumatic cylinder 55. In Fig. 4 the view of the pneumatic cylinder 55 is obscured. If the pneumatic cylinder 55 is vented, the retaining plate 51 is pulled by a spring 56 into a release position in which the retaining plate 51 no longer engages with its end 53 in the slot 54.

[0041] Fig. 5a und 5b show a roll holder for a label printer. In Fig. 5a the roll holder is shown in a sectional drawing. Fig. 5b shows a top view of the roll holder. The roll holder is rotatably mounted in a holder 22 with its horizontal axis 81 via ball bearings 82. The holder 22 continues a vertical support of the label printer in the vertical direction. The axis 81 is with respect to Fig. 7 described below. Fig. 5a und Fig. 5b show the carrier device 60 of the roll holder, which with reference to Fig. 6a und 6b described below. Fig. 5a und 5b also show the clamping device 70, which with reference to Fig. 9a, 9b and 9c as described below. As described in Fig. 5a und Fig. 5b As shown, the roll holder comprises a roll holder 80. The roll holder 80 consists of a base body 84 (see also Fig. 8a und 8b ), which is mounted on the axis 81 via linear ball bearings 86, 87 with angular error compensation so that it can move linearly. The travel of the linear ball bearings 86, 87 on the axis 81 is not restricted by stops on the axis 81, since this travel is restricted by the driver device 60. The base body 84 of the roller holder 80 is designed as an elongated tube 89, which is placed on the axis 81 via the linear ball bearings 86, 87. On the outside of the tube 89 there are three rails 88 which run in the axial direction and are open in the radial direction. In the rails 88 there are clamping plates 83 which are movable in the axial and radial directions, whereby the clamping plates 83 have obliquely arranged guides 93 which are movable via fixed pins 94. The pins 94 are held in bores 91 in the rails 88. Thus, the pins 94 form a fixed guide for the slides 93 within the rails 88.During an axial movement of the clamping plates in one axial direction, the clamping plates 83 are moved radially out of the rails 88 via the pins 94 and the linkages 93. During an axial movement of the clamping plates in the opposite axial direction, the clamping plates 83 are moved radially into the rails 88 via the pins 94 and the linkages 93. Arranged between the rails 88 on the outside of the base body 84 are support elements 85 which are fastened in screw connections 92 of the base body 84. The support elements 85, interrupted by the rails 88, form a round contour of the roller holder 80. The rails 88 have a smaller radial extension than the support elements 85. The support elements 85 thus form a roller holder onto which the roller core is mounted.The diameter of the roll holder 80 formed by the support elements 85 is slightly smaller than the inner diameter of the roll core, allowing the label roll 11 to be easily pushed onto the roll holder 80. The clamping plates 83 protrude from the rails 88 and are radially displaceable. The radial displaceability of the clamping plates 83 extends from a region in which the outer sides of the clamping plates 83 do not protrude radially beyond the support elements 85 to a region in which the outer sides of the clamping plates 83 protrude radially beyond the support elements 85. This makes it possible to clamp the roll core onto the roll holder 80 by radially displacing the clamping plates 83.

[0042] The roll holder further comprises a driver device 60, which transmits a rotational movement of the roll holder 80, which occurs by unwinding the paper strip of the label roll 11, to the axis 81. The driver device 60 comprises, as in Fig. 6b shown a sleeve 62, in the inner area 69 of which the roller holder 80, in particular a closing element 64 ( Fig. 6a ), which is screwed to the base body 84 of the roller holder 80 with screws 65, is attached so as to be axially movable. The end element 64 comprises a pin 63 which engages in an axial slot 66 in the sleeve 62. This allows axial movement of the end element 64 in the sleeve 62. However, the deflection of the axial movement is limited by the length of the slot 66. In this respect, the driver device 60 limits the travel path of the roller holder 80 on the axis 81 of the roller holder in the axial direction. The sleeve 62 is mounted on the axis 81 in a rotationally fixed manner. The rotationally fixed connection is produced in particular via a bore 67 in a wall of the sleeve and an associated recess 68 in the bore 67. The sleeve 62 is mounted with the bore 67 in a receiving area 67' on the axis 81, wherein the axis comprises a nose 68' which engages in the recess 68 and forms the rotationally fixed connection.The sleeve 62 includes holes 61' in a side wall through which the sleeve is connected to a brake disc 61. As shown, the brake disc 61 is braked via a flexible steel band 62 when the pivotable arm 41 of the pivoting device 40 is moved by the spring force of the spring 46 in a direction in which the paper path is extended.

[0043] Fig. 8b shows holes 90, which are present in the axial direction in the base body 84, in which a cylinder 73 of the clamping device 70 is fastened by screws. Likewise, on the other side, in Fig. 8b On the rear and therefore not visible side of the base body there are holes in which the end element 64 is screwed to the base body with screws.

[0044] The clamping device 70 is in the Fig. 9a, 9b , and 9cshown. Basically, the clamping device 70 has the function of axially displacing the clamping plates 83 relative to the base body 84 in the slots 88 of the base body 84. Via the links 93 in the clamping plates 83 and the pins 94, which are firmly connected to the base body 84, the radial position of the clamping plates 83 with respect to the center point of the base body 84 depends on the axial position of the clamping plates 83 in the slots 88 of the base body 84. This means that by axially displacing the clamping plates 83 in the slots 88 of the base body 84, the diameter of a cylinder spanned by the outer edges of the clamping plates 83 changes. This is effected via the clamping device 70.

[0045] Two adjustment mechanisms are implemented via the clamping device 70 to adjust the radial position of the clamping plates 83 in the base body 84, with both mechanisms being implemented with the assistance of an adjustment element 72. The first mechanism changes the position of the clamping plates by rotating the adjustment element 72 and serves to establish a basic setting. The second mechanism is effected by moving an operating lever 71 from a working position, in which the operating lever is aligned perpendicular to the axis 81, to an installation position, in which the operating lever is aligned parallel to the axis 81. This mechanism serves to firmly clamp the label roll 11 onto the roll holder by moving the operating lever 71 from the installation position to the working position, i.e., to move the clamping plates 83 radially outwards with this transfer of the operating lever 71.

[0046] The adjusting element 72 is particularly designed as a single piece and consists of a rotating element 72a, a holder 72b for the operating lever 71, a driving plate 72c, and a sleeve 72d. The sleeve 72d forms the base body of the adjusting element 72 and is open on one side. The driving plate 72c is attached to the sleeve 72d, and the rotating element 72a is attached to the axial end of the sleeve 72d opposite the opening. In the axial direction between the driving plate 72c and the rotating element 72a, there is a defined distance into which the clamping plates 83 engage with a coupling device 94. The coupling device 94 is designed as a hook that engages from the outside into the space between the driving plate 72c and the rotating element 72a, the hook being formed by a sheet metal that has the width of the space between the driving plate 72c and the rotating element 72a.Thus, the sheet metal is contacted on one side by the drive plate 72c and on the other side by the rotating element 72a. If the adjusting element 72 is displaced in the axial direction, the clamping plates 83 are also displaced in the axial direction via the coupling device 94. Since the drive plate 72c and the rotating element 72a are concentric in the area where they contact the coupling device 94, this effect is present regardless of the rotational position of the adjusting element 72.

[0047] The adjusting element 72 is attached to a cylinder 73 with the sleeve 72d, the cylinder forming a sliding surface for the sleeve 72d. The cylinder 73 is firmly connected to the base body 84. A screw 77 is screwed into an internal thread of the cylinder 73. The operating lever 71 is tiltably attached to the screw head 74. Turning the screw 77 changes the distance between the cylinder 73 and the operating lever 71. The operating lever 71 is mounted in the holder 72b of the adjusting element 72 such that it is tiltable, but is connected in a rotationally fixed manner in the direction of rotation of the screw 77. Turning the rotating element 72a consequently leads to a rotation of the operating lever 71 about the axial direction of the screw 77 and to a screwing of the screw 77 in or out of the cylinder 73. The distance between the operating lever 71 and the cylinder 73 is thus reduced or increased.Thus, by rotating the rotating element 72a, the distance between the base body 84 and the area between the drive plate 72c and the rotating element 72a is changed, and thus the clamping plates 83 move axially in the slots 88 of the base body. This causes a change in the radial position of the clamping plates 83 via the guide 93. Thus, by rotating the adjusting element 72, the diameter of a cylinder spanned by the outer edges of the clamping plates 83 can be changed.

[0048] The operating lever 71 has an eccentric 75 at its end, where it is pivotably connected to the screw head 74 of the screw 77. A washer 76 rests on the eccentric on the screw 77. This washer, in turn, rests on the adjusting element 72. If the operating lever 71 is moved from the installation position (not shown in the drawings, in extension of the axis 81) to the working position ( Fig. 9a und 9b) is tilted from the horizontal position to the vertical position by rotating about the screw head 74, the washer 76 on the screw 77 is moved in the direction of the cylinder 73 by the eccentric 75. The adjusting element 72 is moved in the direction of the base body 84. The clamping plates 83 are pushed radially outwards. If the operating lever 71 is tilted from the working position to the installation position by rotating about the screw head 74, a spring (not shown) presses the adjusting element 72 in the direction of the operating lever 71 until the washer 76 rests on the eccentric. The distance between the adjusting element 72 and the base body 84 increases and the clamping plates 83 are retracted. By axially displacing the clamping plates 83 in the slots 88 of the base body 84, the diameter of a cylinder which is clamped by the outer edges of the clamping plates 83 changes and the label roll 11 is tightened or loosened accordingly.The mechanism is enclosed by a cover 78.

[0049] The functions of various elements shown in the drawings, including the functional blocks, may be implemented by dedicated hardware or by generic hardware capable of executing software in conjunction with the corresponding software. If the functions are provided by a processor, they may be provided by a single dedicated processor, a single shared processor, or multiple generic processors, which may in turn be shared. The functions may be provided, without limitation, by a digital signal processor (DSP), network processor, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), read-only memory (ROM) with stored software, random access memory (RAM), and non-volatile memory.

Claims

1. A roll holder for a label roll, in particular for a transversely wound linerless label roll, comprising a horizontally arranged axis which is held on at least one side by a frame, and a rotatable roll holder which is aligned parallel to the axis and is mounted on the axis, characterized in that the roller holder is mounted on the axis with at least one linear bearing so that it can be moved linearly.

2. Roll holder for a label roll according to claim 1, characterized in that the linear bearing is a plain bearing.

3. Roll holder for a label roll according to claim 1, characterized in that the linear bearing is a linear ball bearing, in particular a linear ball bearing with angular error compensation.

4. Roll holder for a label roll according to one of claims 1 to 3, characterized in thatthe axis is connected to the frame in a rotationally fixed manner and the roller holder is rotatably mounted on the axis, wherein in particular the at least one linear bearing is a linear ball bearing which enables both an axial movement and a rotational movement of the roller holder on the axis.

5. Roll holder for a label roll according to one of claims 1 to 3, characterized in that the axis is rotatably mounted on the frame and the roller holder is connected to the axis in a rotationally fixed and linearly movable manner.

6. Roll holder for a label roll according to claim 5, characterized in that the roller holder is connected to the axle in a rotationally fixed manner via a driver and the driver transfers a rotation of the roller holder to the axle.

7. Roll holder for a label roll according to claim 6, characterized in thatthe driver consists of a sleeve with a slot in the axial direction and the sleeve is connected to the axle in a rotationally fixed manner, and a pin connected to the roller holder engages in the slot of the driver.

8. Roll holder for a label roll according to one of claims 1 to 7, characterized in that the sleeve of the driver or the axle is non-rotatably connected to a brake disc, which is connected by a belt to a deflection roller located in the paper path.

9. Roll holder for a label roll according to one of claims 1 to 8, characterized in that the roller holder consists of a base body with at least one rail, wherein the base body is mounted on the axis in a linearly movable manner via the at least one linear bearing and the at least one rail guides an at least radially movable clamping element, in particular a clamping plate.

10. Roll holder for a label roll according to claim 8, characterized in thatthe roller holder has an operating lever at its axial end which can be moved from a working position into an installation position via an eccentric, and the operating lever in the installation position protrudes from the roller holder in extension to the axis of the roller holder, and that the at least one clamping plate is adjusted in the radial direction via the eccentric by moving the operating lever from the installation position into the working position.

11. Roll holder for a label roll according to claim 10, characterized in that the at least one clamping plate comprises a link which runs on a pin in the at least one rail of the base body and the link is arranged such that a movement of the clamping plate in one axial direction of the base body leads to a radial displacement of the clamping plate outwards and a movement of the clamping plate in the other axial direction of the base body leads to a radial displacement of the clamping plate inwards.

12. Roll holder for a label roll according to claim 10 or 11, characterized in that an adjusting element is coupled to the operating lever and a rotation of the operating lever along or against the direction of rotation causes a movement of at least one clamping plate in the axial direction of the base body.

13. Roll holder for a label roll according to one of claims 1 to 12, characterized in that the roll holder comprises a locking device for locking the roll holder in a central position along a displacement path of the roll holder on the axis.

14. A label printer for printing on a paper tape wound on a label roll, comprising a roll holder for the label roll and at least one print head for printing on the paper tape, and a paper path running along the direction of movement of the paper tape from the roll holder to the print head, wherein the label printer comprises a deflection roller along the paper path, along which the paper tape is guided, characterized in that the label printer comprises a roll holder according to one of claims 1 to 13.

15. Label printer for printing a paper tape wound on a label roll according to claim 14, characterized in that the deflection roller comprises a paper guide device, wherein the paper guide device comprises a guide element on each side of the paper strip, wherein the guide elements are adjustable and lockable in the axial direction of the deflection roller.

16. Label printer for printing a paper tape wound on a label roll according to claim 15, characterized in that the deflection roller comprises markings along its axial direction which indicate positions for an arrangement of the guide elements on the deflection roller, and the markings are related to the position of the at least one print head and / or the paper width of the label roll.

17. Label printer for printing a paper tape wound on a label roll according to claim 15 or 16, characterized in thatthe label printer comprises a control device which comprises an input device, wherein the control device receives at least one paper width of a label roll from the input device and the control device comprises a processor which determines axial positions of the guide elements on the deflection roller from the received paper width and displays the axial positions of the guide elements on the deflection roller on a display unit or controls an adjustment unit which moves the guide elements by motor to the determined axial positions on the deflection roller.

18. A label printer for printing a paper tape wound on a label roll according to claim 14 or 17, characterized in thatthe deflection roller is held by a pivoting arm and by pivoting the arm the position of the deflection roller and thus the paper path is changed, whereby the arm is pretensioned by a spring and the spring pulls the arm in a direction in which the distance along the paper path between the roll holder and the print head becomes longer and the tension of the paper belt pulls the arm in a direction in which the distance along the paper path between the roll holder and the print head becomes shorter.

19. Label printer for printing a paper tape wound on a label roll according to claim 18, characterized in thatthe label printer comprises an actuator, in particular a pneumatic cylinder, which moves the arm counter to the spring force into an installation position in which the distance along the paper path between the roll holder and the print head is short, wherein the actuator is triggered by the control device of the label printer and the control device of the label printer triggers the actuator in particular when a sensor detects the opening of the cover of the label printer or the control device receives a signal from the input device that the label roll is to be changed.

20. A label printer for printing a paper tape wound on a label roll according to claim 18 or 19, characterized in thatthe band, which is connected to the brake disc, is fastened at one end to the pivoting arm and the band runs over at least part of the circumference of the brake disc and the band is tensioned around the brake disc when the pivoting arm moves with the spring force and the band around the brake disc is relaxed when the pivoting arm moves against the spring force.

Images