DE3411742A1 - FOLDING MACHINE FOR FOLDING BOWS - Google Patents

Description

description

The invention relates to a folding machine for folding sheets (drawing breaks or the like) and a control such a folding machine.

Folding machines are known for folding drawing pauses, in particular according to a standard-compliant folding program with normal folds and, if necessary, compensating folds, which have a folding mechanism, in front of which transport rollers for inserting the sheet and in front of it - in each case in the sheet feed direction - at least one sensor is arranged to feel its trailing edge, and also a Pulse generator and counter for sheet length measurement and finally a control circuit linking the folding mechanism, the sensor and the pulse generator / counter for determining and executing the folding program, for example from DE-OSes 21 20 204 and 23 17 950. The length measurement takes place in these known machines with the aid of an 'outer classification ^1' , ie several sensors which are arranged along an inlet path for the folded goods at different distances in front of the folding mechanism, provide the control device in conjunction with a sensor arranged at the inlet of the folding mechanism In a sense, it is a rough grid with regard to the length of the sheet to be folded. Depending on which sensors in the sensor chain the trailing edge of the sheet is between

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is located when its front edge reaches the inlet sensor or when the folding mechanism has just formed a fold, the further folding takes place according to a folding scheme provided for this length range. A more detailed statement which length must have for example an opening provided for this folding arrangement compensation fold is derived from the residual length determining by means of the pulse counter, which is made to 'press ¹ of the next sensor by the sheet trailing edge in the course of its further Faltvorschubs.

This' outer classification ^{1 of} the sheet length requires a not inconsiderable structural effort and also has disadvantages in the control of the folding machine.

The resulting task of simplifying and facilitating the required determination of the or a length of the sheet to be folded is achieved by the invention in that the pulse generator is connected to a measuring roller that runs on the sheet without slipping during operation, and that in the sheet feed direction the trailing edge sensor is arranged in front of the measuring roller at a distance from the inlet which is at least as large as the length of the sheet section which is required for the folding sections which, including compensating folds, adjoin a folding section full width on the leading edge side. In this way, an 'inner classification ^{1' is} carried out, so to speak, because the measuring roller not only supplies length measurements via the pulse generator within a classification level (e.g. within a certain folding scheme), but also carries out the classification itself, e.g. selecting one of several folding schemes the control circuit enables.

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For longer sheets to be folded, no (additional) sensor is required to feel the sheet leading edge, because the reversal of the folding mechanism occurring on the occasion of the formation of folds is a corresponding one Can provide reference signal. In a further development of the invention - especially for the case. That also shorter Sheets are to be processed - but there is provision for a leading edge sensor in the sheet feed direction is arranged behind the measuring roller.

The control circuit can then calculate the total length of the sheet as the sum of the pulse count and the distance between the leading and trailing edge sensors. However, it is also possible to leave the control circuit a residual length to be determined, for example the length of what is available for compensating folds Sheet section, with the help of the pulse count between the actuation of the trailing edge sensor and the subsequent folding in the folding mechanism.

The control of a folding machine according to the invention, in particular one of the type discussed above, is based on the fact that a sheet ^{to be folded several times is introduced into the folding machine and placed in successive zigzag folds using a folding mechanism 1} according to a predetermined folding scheme, the folding scheme the maximum length of the sheet sections lying between two folds and the fixed length of a cover sheet section adjoining the last fold, but a length measurement on the sheet determines the length of any necessary compensating fold sections before the cover sheet section.

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Folding schemes of the type mentioned above are provided for example in DIN 824 for drawing breaks. Depending on the sheet length, (longitudinal) folds are first made at equal distances from one another after a somewhat wider sheet section enclosing the filing edge. The same length (width) as JUL also have the sheet section adjoining the last fold and complete the folded package as a cover sheet, because it regularly contains the title block of the drawing. For this it is also necessary that the last fold lies on the binding edge side of the folded package - that is, 'leading edge side ¹ ; the aforementioned cover sheet ends with the trailing edge of the sheet. In order to meet these conditions, it is regularly necessary to provide a compensating fold of shorter length between one or more sheet sections of full fold length (width) and the cover sheet. In those cases in which, because of the dimensional proportions, this compensating fold would be so short that it can no longer be produced, the two preceding folds of full ("maximum") length are added to the compensating length and in this way two compensating double-fold sections are obtained (Compared to the simple compensating fold with two arched sections so a total of four arched sections) of manufacturable length (width).

For an appealing external appearance of the folding package and of course its proper stowability in folders, mailers etc. of standardized size, it is not only important that the folded sheet sections full length are the same size and with their

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The folds on the leading edge lie one above the other, but rather also that the latter is the case with the other arch sections, and that finally the last arch section, So the cover sheet has the correct width (= sheet section length); these being equal to the The maximum distance between the folds of full arch sections or larger (in the latter case, the rear edge protrudes of the sheet slightly beyond the folds on the trailing edge). It has been shown that with all of the above discussed measurements of sheet lengths (total lengths or remaining lengths) it is difficult to use the folding machine in this way control that these conditions are (also) met.

Therefore, the invention also provides that depending on a shortly after the formation of the third to last fold performed measurement of the remaining sheet length, the position of the penultimate fold and thus the length of the last Determined compensation folding section in front of the cover sheet section and the folding mechanism is controlled accordingly will. After the third to last fold has been formed, with the exception of the last fold, the cover sheet 'ties' to the fold all wrinkles that are regularly visible; The latter applies to those under the cover sheet (rear edge side) Do not fold back the compensating fold sections. By the control method described above enabled modification of the penultimate fold, which is the or one of the aforementioned folds is, the position and length '(width) of the cover sheet can be determined very precisely. You can work with others Words the position of the two folds relating to the cover sheet (the penultimate and last) compared to the due Correct the folding program specified in a previous measurement and thus any deviations

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turn off, which are, for example, by adding up Small deviations in dimensions in all previous wrinkles can be very annoying.

Conventional folding controls place, depending on the length measurements discussed above, at the same time as the Faitschema also defines the folding program in detail, that is not only the type and number of folds still to be made, but also their spacing (= length of the arched sections in between). The invention provides a further development of the control specified above before that, depending on a measurement of the remaining arc length at a distance from the arc end (Trailing edge), which is at most equal to the sum of two arch sections of maximum length, of the cover sheet section and two equalizing folding sections of the greatest length necessary, the type and number of down to the last fold (cover sheet section) required folds and then the folds up to third to last folds are formed at predetermined length points of the arch.

So it turns out when determining the length of the sheet to be folded that for the reasons explained above not a compensating double fold (from two arch sections) can be made, but whose, two (from four arc sections) must then be provided thereafter initially the first compensating double fold is formed with arcuate sections of a predetermined length (width). So no consideration is given to the size of the two arch sections of the other equalizing double fold need to be done; it is, however

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It is expedient to have several predetermined lengths ready for the first compensating double fold ¹ , which are called up depending on the individual dimensions. The control of the folding machine is further simplified because only after the third to last fold does the (only) individual determination of the fold position need to take place; all other folding distances are fixed (if necessary with the aforementioned alternative option) for all sheets to be folded regardless of their actual size.

Other developments of the invention are the subject of further subclaims.

The drawing illustrates the invention using exemplary embodiments. It shows:

1 shows the schematic structure of a folding machine with a folding mechanism and Length measuring device;

Fig. 2 in different stages (A - C) the entry of a sheet to be folded in the folding mechanism;

3 is a speed diagram of the folding mechanism drive; and

4 shows a compilation of various

Folding schemes in the form of cross-sectional representations of longitudinally folded packages of bows of different sizes.

The folding machine shown schematically in FIG. 1 has a folding roller frame 1 (outlined by dashed lines) with reversing folding rollers 2, 3 and a corresponding reversing group of adjacent, with the

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Folding rollers 2, 3 co-operating belts 4, which are guided over drive and deflection rollers 5.

The folding rollers 2, 3 form with the belt 4 folding gaps 6, 7. The folding roller frame 1 is controlled so that the The leading edge 8 of a sheet 10 entering through the inlet 9 always enters the folding nip 6 (the folding roller 2) is performed. In the area of this folding gap 6 - slightly behind it in the inlet direction - there is a Sensor 23 is arranged, which senses the leading edge 8 of the sheet 10 entering the folding gap 6; on this will have to be entered.

In front of the inlet 9, the sheet 10 deflecting and interacting transport rollers 11, 12 are arranged. Again in the feed direction of the sheet 10 in front of the transport rollers 11, 12 a measuring device designated as a whole by '13 is provided. It has the measuring roller 15 which is mounted at the free end of a lever 14 and which is set against the direction of advance of the sheet 10 (arrow 16) at the angle cc . It works together with a counter roller 17, which protrudes in a manner not shown through an opening in the table (also not shown) over which the sheet 10 runs in the area of the measuring device 13. The measuring roller acts on a pulse generator 18; this consists of a disk 19 with edge markings, which a scanner receives. The pulses generated in this way are summed up in a counter 21, and the sum of the pulse signals represents a measure of the length of the sheet 10 taken up by the measuring roller 15.

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The above-described design and arrangement of the measuring roller 15 in the context of the measuring device 13 has proved to be expedient in view of the need to use the measuring roller despite constantly changing feed speeds of the sheet 10 (caused by the type of wrinkling with the help of reversing Folding rollers) without slipping on the sheet.

In FIG. 1, the sheet 10 has 8 with its leading edge already pass through the folding gap 6. The various representations of Figure 2 illustrate how up to this time the speed of the folding mechanism drive is controlled or regulated.

In Figure 2A, the leading edge 8 of the sheet 10 is approaching after being between the transport rollers 11, 12 and the Inlet 9 has been guided, the surface of the belt 4, which move - driven synchronously with the folding rollers 2, 3 in the direction of arrow 22 (the arrangement is the mirror image of that in Figure 1). Usually, the sheet 10 has a twist in the region of the leading edge 8, which This is indicated in FIG. 2A by the curvature of an edge section of the sheet under the leading edge 8. It must However, it is ensured that the sheet is stretched smoothly in the folding nip between the folding roller 3 and the Belt 4 arrives.

For this reason, the belt 4 as well as the folding rollers. 2, 3 granted a peripheral speed, the higher is than the feed speed of the sheet 10 (peripheral speed the transport rollers 11, 12). As soon as the leading edge 8 reaches the belt 4, they take the Arc start with that higher peripheral speed

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j and thread the leading edge 8 of the sheet 10 into the Fait- j

gap between the belt 4 and the folding roller 3. \

Figure 2B shows the moment in which the sheet 10 is loading!

already pushed so far through the folding gap i became that the folding roller frame 1 can be stopped,

so that the continued advance of the sheet 1 to a j

Bulging of the sheet 10 between the folding rollers 2, 3 leads. If the drive direction (arrow 22) is now reversed, the bulge (in the usual way) reaches the Folding gap between the folding roller 2 and the belt 4, a fold is formed, and with the sheet 10 pushed behind at the same time, the arc section delimited by that fold with the front edge 8 from its illustrated in Figure 2B Layer transported to the left through the folding gap between the roller 2 and the belt 4.

Back to the inlet situation in FIG. 2A. Once the leading edge 8 shows the tangential line LS between the folding roller 3 and the belt 4 (FIG. 2C) or the ones just behind it Has reached sensor 23, the sheet 10 - because of the aforementioned speed difference - is taut around the adjacent one Area of the folding roller 3 is stretched. At this moment, the peripheral speed of the folding rollers 2, 3 and the belt 4 reduced to the feed speed of the sheet 10.

Figure 3 illustrates this course of the speed. The speed reduction prevents a not exactly perpendicular to the feed direction of the sheet 10 running leading edge, which was also from a previously according to DIN 824 attached diagonal fold can be formed,

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to a lateral warping of the sheet in the folding gap If

leads because the higher peripheral speed of the folding roller 3 and the belt 4 initially grasp the sheet only on one side. But as soon as the arch 10 over the distance L. (Fig. 2C, 3) was transported further, the peripheral speed of the folding roller frame 1 over the distance L ^ again increased to the original value, which during the entire further folding process must be maintained in order to ensure correct folding. Thereby (because of the reversing interruptions) the sheet 10 given the above-mentioned changing feed speed, which allow the transport rollers 11, 12 with friction slip.

Figure 1 illustrates (with arrows directed perpendicularly against the course of the sheet 10) schematically next to the Sensor 23 also has a trailing edge 26 (FIG. 4) of sheet 10 sensing sensor 24 and a leading edge 8 of the sheet 10 sensing sensor 25. To determine the total length of a sheet 10, the starts Sensor 25 the pulse generator 18 when it passes the leading edge of the sheet. Reached the trailing edge 26 of the sheet 10 via the sensor 24, the pulse counting in the counter 21 is stopped, and the total length of the sheet 10 results from the sum of the counted pulses and the distance between sensors 24, 25. -

Since the center of interest is always the length of the compensating folds arched sections is, especially in the case of longer bows, the measurement of the total length can be dispensed with and a Remaining length measurement can be made. If the folding roller frame is already producing folds on a sheet 10, it is necessary before the trailing edge 26 of the sheet 10 has passed the sensor, the signaling by the sensor 25 does not;

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The reversing of the folding roller frame 'adjacent' to the actuation of the sensor 24 can then be used as a reference signal to serve. For example, the pulse generator 18 is only started with the counter 21 when the trailing edge 26 the Sensor 24 passes, and the counting is stopped when the reversing of the folding roller frame 1 (more precisely: the Stopping the folding roller frame before its renewed drive in the opposite direction) the position of the last The fold formed defines: When the sheet 10 is (still) tensioned, the remaining length of the sheet as the path distance between this fold and the sensor 24, reduced by the content of the counter 21 given. From this remaining length can then both the required folding scheme and the (in addition, the individual spacing lengths between the folding program containing the folds in the control circuit - not shown - and determined by this are then carried out by appropriate control of the folding roller frame 1. Figure 4 shows various Examples, namely sheets of different lengths, how different such folding schemes and Folding programs can be; in fact, further variations result from the fact that in the case of two compensating double folds these are not the same, but - for the reasons already explained above - of different lengths (widths) are executed.

In order to determine the position and dimensions of the cover sheet 27 (FIG. 4) in accordance with the control already explained above To be able to determine exactly, a further remaining length determination with the help of the measuring device 13 can only shortly after the third to last fold 28 has been formed (FIG. 4),

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that is, before the formation of the fold 29 (FIG. 4) which is decisive for the position and dimensions of the cover sheet 27. For this purpose, as soon as the folding roller frame is reversed, the one in it is already switched off the folded package formed on the sheet 10 has covered a certain distance, based on the content then available of the counter 21 checked the position of the fold 29 previously determined by the folding program and - if it turns out should that their retention lead to an incorrect length and / or position of the cover sheet 27 would - corrected so that a correct cover sheet position and dimension results.

It is readily apparent that the sensor 24 is at such a distance from the inlet 9 of the folding roller frame 1 or from the sensor 23 or the position of the folds at the reversal point of the folding roller frame drive must be that the length measurements carried out with the aid of the measuring device 13 the execution allow the resulting folding programs. In connection with the control described above becomes in the event that the first remaining length determination results in a folding scheme with two (double) compensating folding sections leads, the first double compensation. folding section in a fixed predetermined length educated. As already mentioned at the beginning, several such fixed, predetermined lengths can be stored and can be called up depending on the measurement result. Subsequent to the formation of the first double compensating fold section The third to last fold 28 formed then takes place the - if necessary corrective - new remaining length determination, as previously described.

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Claims (8)

IRON GUIDE & SPEISER Patentanv'plic --tliiroiXnnPiWrii Attorneys _. - ^ ". ^ OH II IkL Our reference: M 733 Applicant / owner: Meteor .. -, -, patent attorneys File number: New registration Dipl.-Ing. Günther Eiscnluhr Dipl.-Ing. Dieter K. Speiser Dr.-Ing. Werner W. Rabus Date: March 29, 1984 Dipl.-Ing. Detlef Ninnemann METEOR-SIEGEN Apparatebau Paul Schmeck GmbH Frankfurter Strasse 27, 5900 Siegen Folding machine for folding sheets Expectations (1) Folding machine for folding sheets (drawing breaks or the like), in particular according to a standard-compliant folding program with normal folds and, if necessary, compensating folds, with a folding mechanism, in front of which Infeed transport rollers for inserting the sheet and in front of it - in each case in the sheet feed direction - at least a sensor is arranged to feel its trailing edge, with a pulse generator and counter for sheet length measurement, and with a folding mechanism, the sensor and the control circuit linking the pulse generator / counter for determining and executing the folding program, characterized in that the pulse generator (18) is connected to a measuring roller (15) which, in operation runs off the sheet (10) without slipping, EPO - COPY JP ^ Ö Bremen I · Telephone (0421) 32 80 37 Tclecopierer · Telex 02 44 020 lVp.it «1 and that in the sheet feed direction (arrow 16) the trailing edge sensor (24) is arranged in front of the measuring roller (15) at a distance from the inlet (9) which is at least so as large as the length of the arch section which is required for the folding sections, including Connect compensating folds to a full-width fold section on the front edge side. 2. Folding machine according to claim 1, with a further sensor for sensing the leading edge of the sheet, characterized in that the leading edge sensor (25) in the sheet feed direction (arrow 16) behind the Measuring roller (15) is arranged. 3. Folding machine according to claim 1 or 2, characterized in that the measuring roller (15) cooperating with a counter roller (17) is employed at an angle {CC) against the feed direction (arrow 16) of the sheet (10). 4. Folding machine according to claim 2, characterized in that the control circuit measures the total length of the sheet (10) as the sum of the pulse count and the distance between the leading and trailing edge sensors (24, 25). 5. Folding machine according to claim 1 or 2, characterized in that the control circuit measures the remaining length of the sheet section available for compensating folds with the help of the pulse count between actuation of the trailing edge sensor (24) and the subsequent folding in the folding mechanism (1). 6. Folding machine according to at least one of the preceding claims with reversely driven folding rollers ΞΡΟ-COPY £ ß or tapes, in their folding gap, the arch through the Movement of the folding rollers or belts is steered, the peripheral speed of the folding rollers or -belts is greater than the transport speed of the incoming sheet, characterized in that the control circuit controls the peripheral speed of the folding rollers (2, 3) or belts (4) is reduced as soon as a sensor (23) in the area of the first folding gap the leading edge (8) of the sheet (10) or the leading edge sensor (25) in connection with the measuring roller (15) the passage of a distance of this Sensor determines the corresponding sheet length from the first folding gap. 7. Control of a folding machine in particular according to one of the preceding claims, in die.ein several times to be folded sheet introduced and with the help of a folding mechanism according to a predetermined folding scheme in successive Zigzag folds are laid, the folding pattern being the maximum length of between two Arch sections lying in folds as well as the fixed length of a cover sheet section adjoining the last fold, but a length measurement on the sheet of the length of any necessary equalizing folds before the Cover sheet section determined, characterized in that in dependence on one carried out shortly after the formation of the third to last fold (28) Measure the remaining sheet length, the position of the penultimate fold (29) and thus the length of the last Compensating folding section in front of the cover sheet section (27) determined and the folding mechanism (1) controlled accordingly will. A) ΞΡΟ - COPY M? * '£ 8. Control according to claim 7, characterized in that depending on a measurement of the remaining Arc length at a distance from the end of the arc (rear edge 26) which is at most equal to the length of two arc sections maximum length, the cover sheet section and two double compensating fold sections of the largest necessary length is the type and number of folds required up to the last fold (cover sheet section 27) Defined folds and then the folds up to the third from last fold (28) at predetermined length points of the Arc (10) are formed. EPO - COPY * "