EP0645333A1 - Adjustable guide for web material - Google Patents

Abstract

The invention relates to an adjustable guide for web material (1) of differing width, with two lateral guide elements (2,3) which can be positioned at a spacing corresponding to the respective web width and a first of which can be adjusted towards or away from the second, each guide element (2,3) having a guide slot (14,15) for the associated edge region of the web material (1), and the two guide slots (14,15) pointing towards one another. For the optimum guidance of the material (1), it is recommended that the one flank (22), supporting the web material (1), of the guide slot (15) of at least one guide element (3) be displaceable relative to the other flank (24) of this guide slot (15) towards the other guide element (2), preferably be displaceable at least as far as the middle between the two guide slots (14,15). <IMAGE>

Description

The invention relates to an adjustable guide for band-shaped material of different widths with two lateral guide elements that can be positioned at a distance from the respective band width, of which a first can be adjusted towards or away from the second, each guide element having a guide slot for the associated edge region of the band-shaped Has material and the two guide slots point towards each other.

An adjustable guide of the generic type has become known from DE AS 1 235 634. A card-shaped recording medium is passed between two guide elements which can be displaced relative to one another and which grip the edge region on both sides.

A disadvantage is that such a guide can only be used for relatively stiff material, since more flexible tapes - such as a carrier tape with partial areas or labels to be printed - can undesirably deform in the middle area between the guide elements due to a lack of support, so that lateral guidance is no longer guaranteed. In the case of a printing press, for example, however, correct transverse alignment with respect to a printing roller or the like is necessary. necessary.

Starting from the prior art, the invention is based on the problem of improving a guide for band-shaped material in such a way that optimal guidance of the material is guaranteed at all times.

According to the invention the object is achieved in that the flank supporting the one flank of the guide slot of at least one guide element is displaceable relative to the other flank of this guide slot against the other guide element, preferably at least halfway between the two guide slots.

Each guide element has a guide slot for the associated edge region of the band-shaped material and the two guide slots point towards one another. This guidance therefore takes over the guided passage, for example towards the printing area of a printing press. The height of the slot-like guides depends on the maximum thickness of the band-shaped material. In particular, if a relatively wide band runs through the guide and its guide elements only support a comparatively narrow edge region of the band, it is advantageous that the band not only from below at the edge regions, but also over at least part of the region in between is supported. The support can extend over the entire width or almost the entire width. However, because when using a narrower band the two guide elements have to be adjusted towards each other, it is necessary that the effective length of the support surface of one or the other flank, viewed in the direction of adjustment of the guide elements, is also adjusted (ie shortened or lengthened). becomes. In extreme cases the two flanks are of equal length when viewed in the adjustment direction.

The advantage of the invention consists primarily in the fact that the guide is suitable for optimal transport of any width, flexible material, in particular a good guide in the directions orthogonal to the transprot direction is guaranteed.

If both guide elements are adjusted laterally and to the same extent by means of an adjusting spindle, the center of the belt guide is always at the same point on the machine, regardless of its effective width. If a change is made from a wider band to a narrower band, the two guide elements are moved towards one another simultaneously and to the same extent. If, on the other hand, a wider band is to be used, each of the two guide elements is moved outwards, again to the same extent and at the same time. Thus, as required, the belt center is always assigned to the same point on the guideway for the belt, regardless of the belt width. The adjusting spindle is advantageously rotatable but stationary.

Another embodiment of the invention provides that both guide elements can be displaced in a preferably common longitudinal guide. The latter may well be part of a belt processing machine or the like. his. The longitudinal guide prevents the guide elements from rotating when adjusting the adjusting spindle. Thus, a displacement movement of the guide elements can be achieved via the rotary movement of the adjusting spindle.

A further development of the invention in this direction is that each guide element is two at a distance of guide flanks of a guide rail forming the longitudinal guide for the guide elements arranged, preferably parallel sliding surfaces. The guide elements have an essentially cubic shape.

A particularly simple but expedient further development of the above-mentioned embodiment results from claim 5. The slide mentioned there is mounted in the associated guide element so as to be longitudinally displaceable in the adjustment direction, which is why this guide element for accommodating the slide guide in the adjustment direction, i.e. is longer than the guide element without a slide. Otherwise, the two guide elements can be designed quite the same.

A very useful variant of the invention is set out in claim 6. The guide rods mentioned there ensure that the slide on the guide element is guided securely and without tipping over the entire travel distance. For assembly reasons, it can be expedient if the guide elements have different cross sections, for example diameters. Due to the use of guide rods, there is no need for a special guide for the slide in the guide element, so that no tight tolerances are required. It is not even necessary for the slide to be roughly adapted to its guide element in a rough manner.

A particularly preferred embodiment of the invention is characterized in that the carriage carries a first sensor which functions or can be switched at least as a reflex sensor. With the help of such a sensor, one can not only monitor the presence of a belt, but also precisely scan the individual sections of a belt divided into regular sections. The subdivision can be carried out in any way, for example by means of openings or imprints made at recurring intervals, for example in the form of small squares. Reflex sensors of the type in question here are known as such, which is why further explanations are unnecessary. They consist of a transmitter and a receiver and can be delivered in an extremely miniaturized design. Light is emitted via the transmitter, which is reflected on the band. The receiver receives at least part of this light if there is a band or if the band has no breakthrough of any kind in the assigned area. However, if you punch the tape at regular intervals, the light exits through this hole and can no longer be perceived by the receiver. This changed situation can be used in a suitable and known manner, for example for controlling a step-by-step tape feed with feed steps according to the length of the individual sections.

It is easy to see that the tape can have small non-reflective imprints on the underside instead of regularly recurring openings or holes or in addition to these. The effect is exactly the same when the light beam hits such a non-reflective spot. This can also be used for control purposes of the type mentioned. In any case, the sled can take on an additional task in both cases.

The latter also applies to another very advantageous embodiment of the invention according to claim 10. It is used when a tape is used which, for example, is provided with openings or "perforated" on at least one of its longitudinal edges. Of course, this must be the longitudinal edge, which passes through the space between the two opposing sensors. The sensor of the carriage is switched so that it only emits a light beam and this is received by the second sensor located on the other side of the belt whenever a longitudinal slot clears the way. This signal is used in the manner described above. For manufacturing reasons, possibly even for economic reasons, it can be advantageous to design both the first and the second sensor as a reflex sensor with a transmitter and a receiver. Depending on what is to be scanned on the tape, the unnecessary receivers or transmitters must be switched off or on before commissioning.

In this regard, a further embodiment of the invention is proposed, in which the second sensor is switched off when the slide extends and the first sensor located in the slide is switched as a reflex sensor.

• Figur 1 eine Seitenansicht der einstellbaren Führung mit eingefahrenem Schlitten, wobei das bandförmige Material senkrecht zur Bildebene bewegt wird;
• Figur 2 die Führung gemäß Figur 1 mit dem Schlitten in ausgefahrener Position;
• Figur 3 eine Rückansicht der Führung gemäß Figur 1 in Pfeilrichtung A gesehen mit einer in den Figuren 1 und 2 nicht dargestellten Führungsschiene;
• Figuren 4 bis 6 drei verschiedene Varianten des bandförmigen Materials zur Führung in dieser Vorrichtung;
• Figuren 7 und 8 zwei weitere Varianten der Einstellvorrichtung für die Breite der Bandführung.

Further advantages, features and details of the invention emerge from the drawings which show various exemplary embodiments of the invention. Here represent:

• Figure 1 is a side view of the adjustable guide with the carriage retracted, the band-shaped material being moved perpendicular to the image plane;
• Figure 2 shows the guide of Figure 1 with the carriage in the extended position;
• 3 shows a rear view of the guide according to FIG. 1 seen in the direction of arrow A with a guide rail not shown in FIGS. 1 and 2;
• Figures 4 to 6 three different variants of the band-shaped material for guidance in this device;
• Figures 7 and 8 two further variants of the adjusting device for the width of the tape guide.

Essential elements of the adjustable guide for a band-shaped material 1 are two lateral guide elements 2 and 3 for the left and right longitudinal edge of the band-shaped material 1, which are coupled to one another via an adjusting spindle 4. It consists essentially of a right-hand thread 5 and a left-hand thread 6. The lateral guide elements 2 and 3 are equipped with corresponding threaded bores 7 and 8, respectively. The threaded spindle is rotatably supported in symbolically represented walls 9 and 10, for example in a printing press. At its one end projecting outwards, it carries an actuating element 11, preferably a knurled rotary knob. Thus, a clockwise rotation, for example, causes a simultaneous and due to the same thread pitch uniform displacement of the guide elements 2 and 3 in the direction of arrows 12 and 13. A rotation in the opposite direction causes a displacement of the guide elements 2 and 3 against the arrows 12 and 13. Im in the latter case, wider band-shaped materials can be guided in this guide.

The longitudinal edges of the band-shaped material engage, according to FIGS. 1 and 2, in guide slots 14 and 15 of the lateral guide elements 2 and 3. 1, the guide slot 14 or 15 in the direction of displacement (arrows 12 and 13) can be quite shorter than the guide element 2 or 3 itself. The height of the guide slot 14 or 15 is to be chosen so that the thickest guided by this guide band-shaped materials 1 can slide easily.

Because the two threaded bolts 5 and 6 of the adjusting spindle 4 are of the same length and have the same thread pitch (but with different signs) and these threaded bolts 5 and 6 are screwed into the threaded bores of the guide elements 2 and 3 at the same time, the belt center is independent of that Bandwidth always assigned to the center of the adjusting spindle 4. Thus, the band-shaped material 1 is always aligned with the walls 9 and 10 regardless of its width.

According to FIG. 3, the two guide elements 2 and 3 can be displaced in a preferably common longitudinal guide 16. For this purpose, each of the lateral guide elements 2 and 3 has two, preferably parallel sliding surfaces 19 and 20 arranged at a distance from the guide flanks 17 and 18 of a guide rail forming the longitudinal guide 16.

According to FIGS. 1 and 2, each of the two guide slots 14 and 15 has an upper flank 24 and a lower flank 21 or 22 supporting the band-shaped material 1. At least one of the lower flanks, in the exemplary embodiment according to FIGS. 1 and 2 the lower flank 22 of the second lateral guide element 3, is displaceable in the sense of the double arrow 23 with respect to its upper flank 24. As a result, the contact area of the lower flank 22 is greatly increased. In the exemplary embodiment, it can assume three times the length and extend to the center of the adjusting spindle 4. The width of course remains the same. It can be seen from FIG. 2 that in this way the band-shaped material 1 can be supported over most of its entire width.

The extendable flank 22 of the one guide slot 15 is formed by a surface of a slide 25 pointing in the direction of the fixed flank 24, which is slidably mounted on the relevant lateral guide element 3 in the sense of the double arrow 23. The carriage 25 is slidably mounted on two guide rods 26 and 27 which are parallel to the direction of displacement of the guide elements 2, 3 and which engage in or penetrate bores in the two lateral guide elements 2, 3. According to FIG. 2, the length of the guide rods 26 and 27 is equal to the lateral distance between the two walls 9 and 10 and they can be inserted into corresponding bores of the walls 9 and 10 in a manner not shown by means of end pins, similarly as is provided for the adjusting spindle 4 .

The use of the carriage 25 has a very special advantage. This is because it can also be used to attach at least one first sensor 28, which works as a reflex sensor. Reflex sensors are known as such and therefore do not require any further explanation. You have a sender and a receiver. For example, the transmitter emits a light beam that is reflected on a surface provided for this purpose. The reflected light is received by the receiver of this sensor 28. If the reflection is omitted for any reason, it can be used in a known manner for switching purposes, for control purposes, for the purpose of counting or in another known manner. The electronics required for this, a computer or the like. are also known prior art.

Various embodiments of the band-shaped material 1 result from FIGS. 4 to 6. For the sake of simplicity, the band width is chosen to be the same, although, of course, it may vary as intended according to the foregoing.

Dashed lines 29 and 30 indicate that the band is divided into individual sections. The strip-shaped material can certainly be a carrier on which labels are arranged directly one after the other or at the same distance in succession, which are to be printed on in the printer mentioned. The labels can also be connected to one another by means of a perforation. In any case, the two dashed lines 29 and 30 define a tape length that is maximally available for printing. As a rule, appropriate margins are maintained on all sides when printing. However, in order to ensure the exact printing of such labels or partial surfaces 31 of the strip-like material 1, the detection point of the front end 30 and rear end 29 seen in the direction of passage 32 being located in the direction of passage 32 in front of the printing roller of the printing press, these ends 30 and 29 can be recorded very precisely. This is done with the aid of the first sensor 28 mentioned and, if appropriate, also with the aid of a second sensor 32 according to the explanations below.

In the area of the dashed lines 29 and 30 there are various “markings” which can be detected by the sensor or sensors 28 and 32, respectively. In the exemplary embodiment according to FIG. 4, there are slots 33 and 34 which are open at the edge. Instead, the band-shaped material 1 of FIG. 5 provides openings 35 which can be arranged in the center relative to the band-shaped material 1 and are also arranged in the center of the dashed lines 29 and 30. Instead, the exemplary embodiment according to FIG. 6 provides black or dark marks 36 which are on the back of the band-shaped material 1 are attached.

If, when the carriage 25 is extended (FIG. 2), the first sensor 28 is aligned with such a central opening 25 or a middle dark mark 36, switching pulses or counting pulses can be derived from this. In the case of the exemplary embodiment in FIG. 5, the light emitted by the first sensor 28 is reflected until an opening 35 appears above the first sensor 28. The light then emits through this opening 35 and is no longer perceived by the receiver. This means that the dashed line 30 is at a very precisely predetermined distance from the printing roller or the effective surface line of the printing roller. For a given throughput speed of the band-shaped material 1 and a precisely defined distance, the start of printing on this partial area 31 can be determined very precisely by the sensor 28 by means of a precisely operating step switching mechanism. The same applies to the end of the printing process seen in the direction 32.

It is easy to see that a dark or black mark 36 attached to the back of material 1 can do the same. It also follows from the above that it is of course not absolutely necessary to provide the openings or dark marks exactly in the center of the band-shaped material 1. In the case of off-center attachment, the slide 25 with the first sensor 28 must be correspondingly moved further or less to the left or right.

If a band-shaped material 1 according to FIG. 4 is used, the slits 33, 34 open at the edge either on the left or on the right edge, if appropriate also on both edges, or also closed openings on at least one edge region , the first sensor 28 and the second sensor 32 preferably face each other. The two sensors 28 and 32 are not connected as reflex sensors, but rather as a so-called fork light barrier. For example, the sensor 28 emits the light, but does not receive any reflected light. However, if a breakthrough 33 or 34 has arrived between the two sensors 28 and 32, the second sensor 32 can receive the light emitted by the first sensor 28 and emit a corresponding pulse.

The switching of the sensors 28 and 32 from "reflex mode" to "fork light mode" can take place automatically, for example by switching off the slide 25 from the position according to FIG. 1 to, for example, switching off the second sensor 32 and the first one according to FIG Sensor 28 is switched to reflex operation. For this purpose, a switch can be provided on the slide 25. In addition, the slide 25 can be provided with a locking element which locks with the guide element 3 when the slide 25 is retracted.

According to FIG. 7, the lateral spacing of the lateral guide elements 2 and 3 can be brought about by the fact that the longitudinal axis of the adjusting spindle 4 does not run in the direction of the double arrow 23, but perpendicular to it. A pinion 37 is connected in a rotationally fixed manner to the adjusting spindle 4 and can be rotated in the direction of the double arrow 38. At positions of the pinion 37 offset by 180 °, toothed racks 39 and 40 are coupled with this. This means, for example, that when the pinion 37 is turned counterclockwise, the rack 39 moves from right to left and the rack 40 moves from left to right. In this case, the two lateral guide elements 2 and 3 approach each other during the pinion rotation. Because the same toothing is available, one is achieved synchronous approach or removal of the two lateral guide elements 2 and 3 and thus a narrowing or expansion of the tape guide.

Figure 8 shows another variant of such a drive. Here, the adjusting spindle 4 is, for example, rigidly connected to the link 41 of a universal joint 42. The second link 43 is also rotatably mounted on the shaft. Each link 41 and 43 has a fixed articulation point 44 or 45 and a longitudinally movable articulation 46 or 47. In this case, the hinge pin engages in a vertical longitudinal slot 47 or 48. The fixed linkage 44 and the longitudinal slot 47 are located on the first lateral guide element 2, while the fixed bearing 45 and the longitudinal slot 48 are attached to the second lateral guide element 3. A rotation of the adjusting spindle 4, for example in the direction of the arrow 49, brings about a uniform and uniform approach of the two lateral guide elements 2 and 3.

Claims (10)

Adjustable guide for band-shaped material (1) of different widths with two lateral guide elements (2, 3) that can be positioned at a distance from the respective band width, of which a first can be adjusted towards or away from the second, each guide element (2, 3) one Has guide slot (14, 15) for the associated edge region of the band-shaped material (1) and the two guide slots (14, 15) point towards one another, characterized in that the flank (22) supporting the band-shaped material (1) of the guide slot (15) at least one guide element (3) can be displaced relative to the other flank (24) of this guide slot (15) against the other guide element (2), preferably at least up to the middle between the two guide slots (14, 15). Guide according to claim 1, characterized in that the guide elements (2, 3) can be adjusted relative to one another by means of an adjusting spindle, and that the adjusting spindle (4) forms elements of a drive for both lateral guide elements (2, 3), the drive using this second guide element (3) is adjustable relative to the first guide element (2) and at the same time with the latter such that both are moved in the direction of one another (12, 13) or apart. Guide according to one of claims 1 or 2, characterized in that both guide elements (2, 3) can be displaced in a preferably common longitudinal guide (16). Guide according to Claim 3, characterized in that each lateral guide element (2, 3) has two, preferably parallel sliding surfaces (19) arranged at a distance from guide flanks (17, 18) of a guide rail for the guide elements (2, 3) forming the longitudinal guide (16) , 20). Guide according to one of claims 1 to 4, characterized in that the extendable flank (22) of the one guide slot (15) is formed by a surface of a slide (25) which points in the direction of the fixed flank (24) and which on the one Guide element (3) is slidably mounted or displaceable relative to this. Guide according to claim 5, characterized in that the slide (25) is displaceably mounted on two guide rods (26, 27) which are parallel to the direction of displacement (23) of the guide elements (2, 3) and which are in bores in the two lateral guide elements (2, 3 ) intervene or enforce them. Guide according to claim 5 or 6, characterized in that the carriage (25) carries at least one first sensor (28) which operates or can be switched as a reflex sensor. Guide according to claim 7, characterized in that the first sensor (28) is arranged in the retracted initial position of the slide (25) opposite a second sensor (32) attached to the associated guide element (3), the two sensors (28 and 32 ) work as fork light sensors. Guide according to claim 8, characterized in that when the carriage (25) is extended, the second sensor (32) is switched off and the first sensor (28) is switched as a reflex sensor. Guide according to one of Claims 7 to 9, characterized in that the two sensors (28, 32) are connected to a computer and the belt drive has a stepping motor, the number of steps of which is specified by the computer when the belt is fed in steps.

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