Method of folding paper

Abstract

A method for folding paper by means of a folding machine having a folding station, wherein a portion of a paper web (9) supplied to same is firstly folded in a first stack (10) containing continuous sheets and, after reaching a threshold value of the thus-created first stack (10), moved into a stacker (15) and thus remains in contact, via a folded stacking area (12) with a further portion of the paper web (9), wherein a section of the folded stacking area (12) serves as basis for a further subsequent stack of continuous sheets to be folded thereupon. Such method is intended to be developed such that only the smallest possible loops are required. To this end, before moving the first stack (10) into the stacker (15) the folded stacking area (12) is withdrawn out of the folding station from the first already folded stack (10), the folded stacking area (12) is fed back into the folding station while the first stack (10) is moved into the stacker (15), and then the already folded stacking area (12) fed back into the folding station serves as the basis for the subsequent stack to be folded, and the process of withdrawing the folded stacking area (12) after reaching a threshold value of the subsequent stack is repeated until the whole paper web (9) supplied has finished being folded.

Claims

1. A method of folding an elongated paper web with a folding machine having a folding station, the method comprising the steps of sequentially: a) initially supplying a leading portion of the web to the machine and folding the leading portion into a first stack of continuous sheets connected to a following portion of the paper web via a folded trailing sheet of the first stack; b) withdrawing the folded trailing sheet in the folding station from the folded stack; c) moving the first stack into a tray while holding back the folded trailing sheet such that the folded trailing sheet does not move into the tray; d) folding a leading portion of the following portion of the web into a subsequent stack with the folded trailing sheet of the first stack constituting a leading sheet of the subsequent stack and a trailing sheet of the subsequent sheet connecting the subsequent stack to a following portion of the paper web; and e) after each execution of step d) repeating steps b) through d) until the whole paper web supplied is completely folded.

2. The method according to claim 1, wherein the stack is fed alternatingly between three folding rollers of the folding station into the guide plates, wherein after reaching a threshold value, the paper web is folded between the folding rollers in the next folding step, the folding rollers and the supply rollers upstream therefrom are reversed after folding is completed after the folds have left the gap between the folding rollers, the folding rollers are reversed again, while the supply rollers continue pulling the folded trailing sheet further out of the folding station, at this point the first stack is guided into a guide plate and outward via same, the supply rollers are then reversed when the next to last fold has exited the gap between the folding rollers, and after the stack has left the guide plate and reached the tray, the folding rollers are reversed for stacking again.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The invention is described below in greater detail using drawings.

(2) FIGS. 1 to 8 show a folding machine operated and controlled using the method according to the invention.

SPECIFIC DESCRIPTION OF THE INVENTION

(3) The drawing shows a folding station 16 formed between a roller 1 and rollers 2 and 3 cooperating with the roller 1. Guide plates 4 and 5 are associated with the roller 1. Supply rollers 6 and 7 feed a paper web 9 in a direction 8 to the rollers 1 to 3.

(4) FIG. 1 shows a first folded stack 10 made from the paper web 9 positioned between the rollers 1 and 2 and juxtaposed with the guide plate 4. The rollers 1 to 3 are repeatedly reversed to form folds 11 between the rollers 1 and 3 as shown in FIG. 2. Immediately following formation of the folds 11, the rollers 1 to 3 and supply rollers 6 and 7 are reversed as shown in FIG. 3. Reversing the supply rollers 6 and 7 then causes a trailing sheet 12 of the paper web 9 to be pulled from the folding station 16.

(5) After the folds 11 have exited the gap between the rollers 1 and 3, the rollers 1 to 3 are reversed again, while the supply rollers 6 and 7 continue to pull the trailing sheet 12 of the paper web 9 farther out of the folding station 16 (see FIG. 4).

(6) FIG. 5 shows a loop 13 resulting from the withdrawing of the trailing sheet 12 of the paper web 9 from the folding station 16 and the continued feeding of the paper web 9 to the folding station 16. As FIG. 5 illustrates, the first stack 10 is fed back by the rollers 1 and 3 and toward the guide plate 5. After the second to last fold 14 has exited the gap between rollers 1 and 2, the supply rollers 6 and 7 are reversed (see FIG. 6). The trailing sheet 12 is then fed back into the folding station 16. The loop 13 is eliminated again.

(7) As FIG. 7 illustrates how the first stack 10 is conveyed outward toward the tray 15 (FIG. 8) via the guide plate 5. After the first stack 10 has reached the tray 15 and the folds 11 are advanced into the guide plate 5 according to the planned length of the paper web to be folded, the rollers 1 to 3 are reversed again. Folding of the subsequent stack is thereby resumed between rollers 1 and 2 as in FIGS. 1-7.