WO1985002374A1

WO1985002374A1 - Endless arrangement of sets of forms

Info

Publication number: WO1985002374A1
Application number: PCT/EP1984/000378
Authority: WO
Inventors: Jürgen Grosse
Original assignee: Grosse Juergen
Priority date: 1983-11-30
Filing date: 1984-11-30
Publication date: 1985-06-06
Also published as: FI852930A0; DE3466960D1; FI852930L; EP0165277A1; EP0165277B1; DE3343380A1

Abstract

Endless arrangement of sets of forms, wherein the length of the different superposed sheets is regularly graduated, a certain length difference existing between the longest upper sheet and the shortest lower sheet. This enables to avoid the difficulties such as the formation of beads, the unstapling operation, removal of the form set which occurred heretofore when filling the sets of forms with a table printer.

Description

Endless arrangement of form sets

The invention relates to an endless arrangement of form sets according to the preamble of claim 1.

For the increasing number of workplace printers, which are arranged decentrally and are operated via computer systems at screen workstations, not only endless forms but also endless arrangements of form sets are necessary. These consist of several continuous webs arranged one above the other, which are connected to each other by a stitch at the edge of the form. Difficulties arise when thicker copying rates are to be processed.

The impact of workplace printers is generally sufficient for six to sevenfold sets. The actual difficulties arise - due to the construction of the form guide - during the run, ie when the form sets are transported through the writing mechanism. In the form guide, the form set is usually drawn in via spiked tractors, directed around a platen roller at the printing point and led out at a different point by a spiked tractor. The angle of the deflection between the two tractor guides is sometimes over 180 °. Due to this strong deflection, the lower paper web lying against the platen roller runs a shorter distance than the upper webs of the form set. Since the endless webs are all made of the same length for manufacturing and measuring reasons, the lower webs move so far after a few form lengths that the edge holes are covered and the form set jumps out of the tractor guide. A bead can also form on, in front of or behind the platen roller, which staples the webs and causes them to run sideways.

The remedial options known so far, explained below, all have considerable deficiencies.

A first, obvious option is to use only form sets with a small number of copies. In the case of a breakthrough, the shift explained above is insignificant; in the case of two breakthroughs, it is just bearable under favorable conditions. The obvious disadvantage of this solution is that one or two copies are rarely sufficient. The

A way out of writing the form set several times is obviously very uneconomical and also entails the risk that deviations between the individual form sets occur. Another possibility is to strengthen the sentence connection. Instead of the inexpensive and easily detachable crimplock stapling (claw-like stampings on the edge of the form), the more expensive and more difficult-to-detachable multiflex stapling has been provided, in which a narrow strip of self-adhesive paper is drawn through a larger punched edge hole and onto the first and last sheet of the form set is glued.

However, this multiflex stapling does not prevent moving, but only provides a somewhat greater resistance. Often you have to attach the Multiflex stapling again in the opposite direction. This then reduces the shift even further and prevents jumping out of the form guide; the above-mentioned bulge and the resulting shift in the print image remain. There are also wrinkles that affect the appearance and the

Hinder further processing. Furthermore, since the paper loops have to be torn when separating the webs, separating the endless sets connected with Multiflex is much more complex than separating a crimplock stitch.

Another known solution is to use carrier sheet sets. They consist of an endless carrier web, to which individual sentences are glued. This prevents bulging. The disadvantage of a shift of the print image to the one below the other beating remains however. In addition, the carrier tape sets can only be produced with such large stand tolerances in the print that a division of the pre-printed area by lines is forbidden, unless tolerances of ± 2 mm or more are available.

The invention is therefore based on the object, while avoiding the shortcomings described, to form an endless arrangement of form sets in such a way that the formation of a bulge in the lettering in the printer is avoided even when there are a plurality of webs arranged one above the other, no shifting of the print image occurs and also at Using an easily releasable stapling (like the crimplock stapling) there is no risk of stapling in the printer.

This object is achieved according to the invention by combining the following features:

a) The length of the individual tracks is evenly graded, with the following percentage difference in length between the top, longest track and bottom, shortest track:

V = d.U.K + 2nd.U. (1 E -K), r

where mean: d = thickness of all webs in the form set from the first to the last but one web (in mm)

U = wrap around the platen (in%)

r = radius of the platen (in mm)

E = clamping length (in mm)

V = difference in length between the top and bottom lanes (in%)

K = coefficient of friction (can take values between 0 and 1)

b) the sheets arranged one above the other are stapled in such a way that - with uniform distribution of the entire length difference over the individual form sets - the dividing lines between successive form sets for all sheets lie one above the other.

The above-mentioned clamping length E is to be understood as the length of the form web clamped in the printer, starting from the point at which the webs have to lie one above the other for the first time to the point at which this must be the last case. On the basis of FIG. 3 it will be explained in detail which length is to be regarded as the clamping length in the different types of form guides. The wrap U (expressed in% of 360 °) in the above formula is the angle which is formed between the point of first contact of the form web with the platen roller and the point of last contact.

The coefficient of friction K can take values between 0 and 1 depending on the conditions. 1 extremely high friction (stationary platen, fixed stapling, rough papers) and 0 extremely low friction (moving platen, without stapling, extremely smooth papers).

In individual cases, the coefficient of friction K is taken from tables that were determined by tests.

As can be seen from the above formula for the percentage length difference between the top, longest path and the bottom, shortest path, the lengthening is greater, the smaller the clamping length and the radius of the platen and the greater the wrap of the platen and the thickness the papers is. The extension is also greater the smaller the coefficient of friction K to be taken into account.

The variation of the length of the individual webs provided according to the invention does not interfere with the stacking of the form sets in the zigzag stack. The change in length is compensated for in each outer fold. On the other hand, a certain problem is the gathering of the webs in the production of the endless arrangement of form sets and the attachment of the set connection (stitching on the edge of the form).

An expedient embodiment of the invention therefore relates to a device for stapling the webs of the endless arrangement of form sets according to the invention. This device is characterized by the features of claim 2.

The invention is explained below with reference to the drawing. Show it

1 and 2 are schematic diagrams for explaining the endless arrangement of form sets according to the invention,

3 shows a schematic diagram of various form guides in workplace printers,

4 shows a schematic of a device for stapling the webs of the endless arrangement of form sets according to the invention.

1 shows an endless arrangement 1 of form sets according to the invention before stapling. It consists of a plurality of continuous webs 2a to 2k arranged one above the other, the thickness being calculated from the uppermost web 2a to the second-lowest Lane 2i is designated d.

The length of the individual tracks 2a to 2k is stepped uniformly, being between the uppermost, longest track 2a and the lowest, shortest

Lane 2k there is a percentage difference in length V.

2 illustrates the endless arrangement 1 'in the stapled state. The individual form sets are labeled 1a to 1m, the dividing lines between successive form sets are labeled 3a to 3n. As can be seen from the schematic illustration in FIG. 2, the webs 2a to 2k arranged one above the other are stapled such that the

Separation lines 3a to 3n between successive form sets for all lanes lie exactly one above the other. This means that the entire length difference V of the form set (see Fig. 1) was evenly distributed to the individual form sets 1a to 1m during stapling. Since the length difference V is of the order of a few percent, it cannot be seen in the schematic illustration in FIG.

The various common form guides in workplace printers are shown in a schematic form in FIG. 3, the clamping length E to be taken into account in the extension formula being shown. Show in detail

3a to 3d form guides with tractors 4, pressure rollers 5 and pressure rollers 6,

- and Figures 3e and 3f form guides with a spiked roller 7 and pressure rollers 6.

Taking into account the different device settings, there are the following variants:

Wrapping variant device setting angle

Fig.3a 180º a pressure roller fixed b pressure roller movable

Printing roller movable with pressure rollers

Fig.3b 135º d printing roller fixed e printing roller movable

Printing roller movable with pressure rollers (clamping length is designated here with E ')

Fig.3c 45º g pressure roller fixed with brush brake h pressure roller movable with brush brake Wrapping variant device setting angle

Fig.3d 135º i pressure roller fixed j pressure roller movable

Fig.3e 180º k with brake rollers l with pressure rollers

Fig.3f 130º m with brake rollers n with pressure rollers

The following numerical examples for the form guides a, 1 and h may serve to explain the invention, typical values for the coefficient of friction K being assumed in each case:

Variant a Variant 1 Variant h

r = 20 mm r = 20 mm r = 20 mm d = 1 mm d = 1 mm d = 1 mm U = 50% U = 50% U = 12.5% E = 250 mm E = 50 mm E = 170 mm K = 0.5 K = 0.9 K = 0.4

Extension V for the top sheet: 1.87% 2.35% 0.52%

Fig. 4 illustrates in a schematic form

Device for stapling the webs of an endless arrangement of form sets according to the invention. It contains a support roller 8 partially wrapped by the endless arrangement, with which a stitching roller 9 interacts. Furthermore, two transport elements 10, 11 in the form of spiked wheels are arranged on the inlet and outlet sides of the support roller 8. These transport members 10, 11 are pivotable in the direction of the double arrows 12, 13, so that their relative position or their distance can be adjusted. As a result, the angle at which the endless arrangement 1 wraps around the support roller 8 can be set to the desired value.

The webs 2a to 2k running in through the transport member 10 are stapled on the edge of the form by the stapling roller 9 and placed in a zigzag stack 14 after the transport member 11. Depending on the chosen extension V (ie the difference in length between the top web 2a and the bottom web 2k), the wrap angle of the support roller 8 is adjusted by means of the adjustable transport members 10, 11 so that the dividing lines between the successive form sets for each web lie exactly one above the other .

When the endless arrangement of form sets according to the invention is used, the printing press is set precisely to the form length of the individual web (when the webs 2a to 2k of different lengths later lying one above the other are thus printed, one is carried out Correction of the press setting). This can be done in a simple manner, for example by means of a measuring rail of approximately 3 m in length made of metal, which contains pins at one end for receiving the edge perforation and at the other end after exactly 10 pre-printed forms at a height of 12 "(standard format) a scale that is ten times extended , on which the length can then be read.

Claims

Claims:

1. Endless arrangement of form sets, consisting of several continuous sheets arranged one above the other, which are connected to each other at the edge of the form by stapling, characterized by the combination of the following features:

a) the length of the individual tracks is evenly graded, with the following percentage difference in length between the top, • longest track and the bottom, shortest track:

V = d.U.K + 2πd.U. (1-K), r E

where mean:

d = thickness of all webs in the form set from the first to the last but one web (in mm)

U = wrap around the platen (in%)

r = radius of the platen (in mm)

E = clamping length (in mm)

V = difference in length between the top and bottom lanes (in%) K = coefficient of friction (can have values between

Assume 0 and 1),

b) the sheets arranged one above the other are stitched in such a way that - under even

Distribution of the total difference in length among the individual form sets - the dividing lines between successive form sets for all lanes lie one above the other.

2. Device for stapling the webs of an endless arrangement of form sets according to claim 1, characterized by:

a) a support roller (8) partially wrapped around by the endless arrangement (1), with which a stitching roller (9) interacts,

b) and two rotatable transport members (10, 11) arranged on the inlet and outlet sides of the support roller (8),

c) wherein the wrap angle of the support roller (8) can be adjusted by changing the relative position of the two transport members (10, 11) such that the dividing lines (3a to 3n) between successive form sets (1a to 1m) one above the other in the area of the stitching roller (9) lie.