JP2017024911A - Buckle folding unit and sheet-fed folding machine including the buckle folding unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a buckle folding unit and a sheet-fed folding machine including the buckle folding unit capable of advantageously improving the quality of the fold.SOLUTION: A buckle folding unit for sheets 1000 includes: a folding plate 33 and three rollers 32.1, 32.2, 32.3 that form a transport roller pair 32.1, 32.2 and a folding roller pair 32.2, 32.3; and at least one blown-air nozzle 40 for guiding the sheet elements 1000. The blown-air nozzle 40 emits a blown-air jet 42 in a direction radial to a common roller 32.2 of the transport roller pair and the folding roller pair. The air jet places the sheet against the surface of the common roller 32.2 and guides it into a nip of the folding roller pair in a defined way.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a buckle folding device having the configuration according to claim 1 and a sheet folding machine including the buckle folding device according to claim 7.

BACKGROUND ART Buckle and knife folders are known in the prior art. A combination of a buckle folding station and a knife folding station is widely known as a combination type folding machine. In the combination type folding machine, parallel folding is performed in the buckle folding apparatus, and right-angle folding is performed in the subsequent knife folding apparatus. In the buckle folding machine, the sheet passes through at least the following stations in the conveyance direction: a sheet feeding device, a transfer table (feed table), a buckle folding device, and a sheet discharge unit.

  The configuration of a buckle folding machine provided with a plurality of buckle folding devices is apparent in DE 10 2004 047171. In this configuration, each buckle folding device includes one folding plate and three folding rollers, and the folding plate and the folding roller are disposed on two folding roller pairs.

  In the known prior art, it is known to use an air nozzle for the folding plate. The air nozzle is used to reliably guide the sheet to be conveyed through the buckle folding device in a purpose-oriented manner. In EP 1577244 it is proposed to use a blow-off air nozzle in a folding plate arranged in the upper sheet guide just behind the upper plate inlet. The blowing air nozzle generates an air flow that travels substantially in the direction of entry of the folding plate and thus assists the entry of the sheet until the leading edge of the sheet contacts the folding plate stopper. In one possible embodiment, the blown air nozzle is configured for that purpose as a venturi nozzle.

  The use of blown air nozzles for folding plates is also described in German Utility Model No. 8906505, US Pat. No. 2,699,331 and German Utility Model No. 7029693. The last German utility model No. 7029693 discloses a Kannon folding plate for carrying out Kannon folding. The function of the blown air nozzle that functions using compressed air is to ensure the reliable entry of the folded product already produced by the first folding device, which already has one fold, into the folding plate of the second buckle folding device. It is to be. According to one embodiment, the plurality of blowing air nozzles form part of a blowing tube extending across the entire width in the folding plate.

  So-called collecting plates are known, for example as described in EP-A-0511574. Such an assembly plate is used to collect a plurality of individual sheets fed to the assembly plate one after the other. The collected sheets are subsequently ejected from the collective plate together and fed to subsequent folding devices so that the collected sheets can be folded together.

  For example, in German Patent Application Publication No. 102008048286 and German Patent Application Publication No. It is known. In this case, it is particularly difficult to guide the sheet when entering and leaving the folding device (specifically, the folding plate).

  The disadvantage of the folding device described above is that, especially at high speeds, the sheet cannot be reliably transported through the folding device to the subsequent folding device, which damages the sheet or impairs quality, for example, when introducing the fold. Folding or post-folding can occur.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a buckle folding device in which guide of a sheet-like element is improved in the buckle folding device.

  This problem is solved by a buckle folding device having the configuration described in the characterizing portion of claim 1.

  The buckle folding device according to the present invention is used to fold a sheet-like element that can be supplied even in a lower stack, in particular a sheet made of paper, cardboard and plastic, and comprises one folding plate and three rollers, Two of the rollers constitute a conveying roller pair for supplying the sheet-like element, and the other two of the rollers constitute a pair of folding rollers for folding the sheet-like element. At least one blown air nozzle is provided for guiding the element. The blown air nozzle is preferably supplied with, or supplied from, at least one blown air nozzle, a blown air jet directed radially to a common roller of the conveying roller pair and the folding roller pair. Configured and positioned as such. The orientation of the blown air jet in the radial direction means that the blown air is directed from the blown air nozzle toward the central axis of the folding roller on the inlet side of both folding rollers. As a result, the sheet-like element is brought into contact with the surface of the roller described above and guided to the roller gap of the pair of folding rollers in a predetermined shape, whereby the folding quality can be improved.

  According to a preferred refinement, a control unit for activating the blown air nozzle by controlling the timing of the blown air nozzle in accordance with the purpose is assigned to the blown air nozzle. Thus, the blown air jet can be activated when the front edge of each sheet-like element abuts on or just before the front edge stopper of the folding plate.

  According to a particularly preferred and thus advantageous refinement of the buckle folding device according to the invention, it comprises a plurality of blowing air nozzles arranged side by side in the nozzle strip, in which case these nozzle strips are substantially folded plates Or it extends over the width of the folding roller.

  According to an improved embodiment of the buckle folding device, the folding plate is arranged with an entry angle of 20 ° to 40 ° with respect to the entry plane of the sheet-like element into the buckle folding device. In this case, the entrance plane is a plane in which the sheet-like element is conveyed to the folding plate through the pair of conveying rollers and at the same time the common tangent line of both conveying rollers is located. Placing the folding plate at a flat angle helps with easy entry of the sheet into the folding plate.

  According to a particularly preferred and thus advantageous refinement of the buckle folding device, at least another roller of the folding roller pair, i.e. a folding roller on the plate side rather than a folding roller on the inlet side, which is not part of the conveying roller pair Is provided with at least one groove on its surface, in particular a groove extending annularly around the outer peripheral surface, a so-called cut. The groove is processed as a recess on the surface of the roller. As a result, air existing between the sheet-like element and the pair of folding rollers can be released more quickly and better during the folding process. Thus, on one side of the sheet-like element, that is, below the sheet-like element, an increase in pressure is avoided in a so-called folding space, and the folding quality is improved.

  The present invention also relates to a sheet folding machine including the buckle folding device as described above.

  A nozzle strip comprising a plurality of blown air nozzles as described above may also be used for the reversing plate, as described, for example, in EP 1925579.

  The described invention and preferred improvements of the described invention, together with each other, constitute a preferred improvement of the present invention when combined with each other.

  For further advantages and for structural and functional aspects of preferred embodiments of the invention, reference is made to the dependent claims and to the description of the embodiments with reference to the accompanying drawings.

The present invention will be described in more detail with reference to the accompanying drawings. Components and members corresponding to each other are provided with the same reference numerals in a plurality of drawings. In order to make the drawings easier to see, they are not shown to scale.

It is a figure which shows the sheet folder based on this invention. It is a figure which shows the buckle folding apparatus by a well-known prior art. It is a figure which shows the buckle folding apparatus by a well-known prior art. It is a figure which shows the buckle folding apparatus which concerns on this invention. 1 shows a side view of one embodiment of a buckle folding device according to the invention. 1 shows a plan view of one embodiment of a buckle folding device according to the present invention.

  FIG. 1 shows a sheet feeder 10, a supply station 20 having an alignment table (feed table), a buckle folding station 30 having two buckle folding devices 30.1 and 30.2, and a signature discharge unit 50. The sheet folding machine 100 provided is shown. In the area of the sheet feeder 10, each sheet 1000 is separated from the pile 1001 and passed to a supply station 20 having an alignment table. Each sheet 1000 is supplied from the supply station 20 to the buckle folding station 30 in the sheet conveyance direction T. In this case, the sheet 1000 can be processed by the slitter shaft 31 provided in advance for preparation of the fold. In the buckle folding station 30, actual processing, that is, folding of the sheet 1000 by cooperation of the folding plate 33 and the folding roller 32 is performed. The configuration of the buckle folding station 30 will be described in detail below based on other drawings. The sheet 1000 completely folded at the buckle folding station 30 is discharged as a signature 1002 to the signature discharge unit 50.

  2a and 2b show a known prior art buckle folding device 30.1. Each sheet 1000 is moved in the folding plate 33 until the leading edge of the sheet 1000 contacts the leading edge stopper 34 by the two rollers 32.1 and 32.2 constituting the pair of conveying rollers in the sheet conveying direction T. It is conveyed to. Then, in the folding space 36, as shown in FIG. 2b, a bend is formed, and the sheet 1000 is captured in the folding gap between the rollers 32.2 and 32.3 constituting the folding roller pair. The actual folding process is performed. The progress of the buckle formation depends on many factors, that is, the sheet traveling speed, the sheet basis weight, the configuration of the folding plate entry portion 35, the width of the sheet 1000, the surface of the roller 32, and the like.

  In order to improve the folding quality, a nozzle strip 41 having a plurality of blown air nozzles 40 is arranged in the entry area 35 of the folding plate 33, ie in the area of the upper plate lip, as shown in FIG. In this case, the blown air nozzle 40 has an air jet 42 that is directed radially with respect to the second roller 32.2, i.e. towards the central axis of the second roller 32.2. Oriented to supply. The air jet 42 ensures that the sheet 1000 is placed on the second roller 32.2 in a planar shape, and as a result, is guided into the folding roller gap between the pair of folding rollers 32.2 and 32.3 in a predetermined shape. Act on. In contrast, an air jet that is directed directly into the gap between the folding rollers does not improve folding accuracy, the introduction of the folding process is mainly governed by the air flow, and the crease formation is no longer accurately reproducible. it is conceivable that. This is because the sheet “flutters” into the gap between the folding rollers of the pair of folding rollers. In contrast, the present invention provides a highly accurate introduction of the folding process that is reproducible for any sheet based on the radially oriented air jets 42. In any case, the formation of the fold is mainly due to the geometrical state of the folding device 30.1, ie based on the position of the plate stopper 34.

  In the embodiment shown in FIG. 3, the folding plate 33 is oriented with an entry angle α of about 25 ° with respect to the entry plane E. Unlike the general approach angle of about 45 ° according to the known prior art, the sheet 1000 can easily enter the folding plate 33 and avoid an entry trouble.

  The blown air nozzle 40 may be incorporated into the nozzle strip 41 at the illustrated position. The nozzle strip 41 extends over the width of the folding plate 33 or the folding roller 32 (see FIG. 4b). Further, as shown in FIG. 4b, the nozzle strip 41 is connected to a blown air source, and can be supplied with blown air with timing controlled by a machine control device. For this purpose, a sensor connected to the machine control device in terms of data technology may be incorporated in the buckle folding device 30.1. The sensor monitors the abutment of the leading edge of each sheet 1000 at the plate stopper 34 and sends a pulse to supply blown air.

  In the embodiment shown in FIG. 4a, at least one groove 37, a so-called notch, is machined on the surface of the folding roller 32.3 on the plate side. The groove 37 is formed by a recess on the outer peripheral surface of the folding roller 32.3, and is configured to endlessly extend around the outer peripheral surface of the roller 32.3, in particular, endlessly. Thus, the groove 37 forms an air passage. This air passage assists in escaping air located below the sheet 1000, that is, between the sheet 1000 and the pair of folding rollers 32.3 and 32.3. Since the sheet 1000 cannot be easily brought into close contact with the folding rollers 32.3 and 32.3, it is inconvenient during the introduction of the folding process. The air existing there is the bearing side end of the folding rollers 32.3 and 32.3. In addition to the portion, it is possible to escape through the groove 37 additionally. As shown in the plan view of FIG. 4b, a plurality of grooves 37 are formed on the outer peripheral surface of the folding roller 32.3.

DESCRIPTION OF SYMBOLS 10 Sheet feeder 20 Supply station 30 Buckle folding station 30.1 1st buckle folding device 30.2 2nd buckle folding device 31 Slitter shaft 32 placed in front 32 Folding roller 32.1 First roller 32.2 2nd Roller 32.3 Third roller 33 Folding plate 34 Plate stopper 35 Entrance (upper plate lip)
36 Folding space 37 Groove 40 Blowing air nozzle 41 Nozzle strip 42 Air jet 50 Signature discharge unit 100 Sheet folding machine 1000 Sheet 1001 Pile 1002 Signature (folded sheet)
E approach plane T transport direction α approach angle

Claims (7)

A buckle folding device (30.1, 30.2) for a sheet-like element (1000),
One folding plate (33);
A pair of conveying rollers (32.1, 32.2) for supplying the sheet-like element (1000) and a pair of folding rollers (32.2, 32.3) for folding the sheet-like element (1000) are configured. Three rollers (32.1, 32.2, 32.3);
At least one blowing air nozzle (40) for guiding the sheet-like element (1000);
A buckle folding device comprising:
At least one of the blown air nozzles (40) discharges a blown air jet (42) directed in a radial direction with respect to a common roller (32.2) of the conveying roller pair and the folding roller pair. A buckle folding device characterized by that.   The buckle folding device according to claim 1, wherein a control unit for activating the blown air nozzle by timing control is assigned to the blown air nozzle (40).   The buckle folding device according to claim 1 or 2, wherein the buckle folding device (30.1, 30.2) comprises a plurality of the blowing air nozzles (40) aligned side by side in a nozzle strip (41).   The folding plate (33) is arranged with an entry angle (α) of 20 ° to 40 ° with respect to the entry plane (E) of the sheet-like element (1000). The buckle folding apparatus of any one of Claims.   The buckle folding device according to any one of claims 1 to 4, wherein at least one groove (37) is provided on a surface of at least another roller (32.3) of the pair of folding rollers.   The buckle folding device according to claim 5, wherein the at least one groove (37) is configured as an endlessly extending groove on the outer peripheral surface of the roller (32.3).   A sheet folding machine (100) comprising at least one buckle folding device (30.1, 30.2) according to any one of the preceding claims.