JPH0192175A - Method for folding up sheet - Google Patents

Abstract

PURPOSE:To form a fold with a simple method while simultaneously enabling the bitting of the fold by making the width in the circumferential direction of the groove of a grip roller matched with the sum of twice the thickness of a sheet and the thickness of the end part of a folding plate. CONSTITUTION:The width in the circumferential direction of a groove 2 in the axial direction on the peripheral face of a bitting roller 1 is matched with the sum of twice the thickness of a sheet S and the thickness of the end edge part of a folding plate 3 projecting out of the peripheral face of a folding roller 4, and the fold forming position of the sheet S is pushed into this groove by means of the end part of the folding plate 3. Thereby, a fold so is formed and, when the end part of the folding plate 3 is retracted from the inside of the groove 2, the fold So is kept gripped by the groove 2 to carry out the folding action of gathering the wings on both sides of the fold So of the sheet S together. In this case, even if the end part of the folding plate 3 which is thrust inside the groove 2 with the rotation of both rollers 1, 4 may be momentarily in a firm fit-in condition with the inner walls of the groove in the most deeply thrust position, since the peripheral speed of both rollers are equal in this part, the end part of the folding plate 3 will not be damaged.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a sheet folding method for folding napkin paper, tissue paper, and various other flat-fed sheets.

(Prior art) In order to fold a sheet, a folding roll is used, in which the tip of a folding plate fixed in the axial direction protrudes radially from the circumferential surface, and an axial groove into which the tip edge of the folding plate enters is formed on the circumferential surface. The folding rolls having the above-mentioned folding plates are opposed to each other and rotated synchronously, and the folding plate is pushed into the groove of the folding roll with the tip of the folding plate, thereby creating a crease in the sheet. It is known to form.

(Points to be solved by the invention) In the above-mentioned known method, the circumferential speeds of the outer periphery of the folding roll and the outer periphery of the gripping roll are made equal, so the circumferential width of the groove of the gripping roll is It is necessary that the tip of the folding plate protruding from the circumferential surface of the folding roll be made sufficiently wider than the thickness of the tip so that it can enter and exit the groove without any problem. Therefore, even if both rolls rotate synchronously and the tip of the folding plate or the sheet crease is once pushed into the groove of the gripping roll, the tip of the folding plate or the folding edge of the sheet will be pushed into the groove of the gripping roll. When the sheet is moved out, the folded portion of the sheet that has been pushed into the groove also escapes from the groove. In order to prevent this, either a negative pressure is applied in the groove to suck the folded part of the pushed sheet, or a mechanical holding device using a cam or a spring is built into the groove. However, the structure is very complicated and the manufacturing cost is high.Especially when using a vacuum suction method, the exhaust noise of the pump is loud, causing noise pollution problems.

<Means for Solving the Problems> Therefore, the present invention provides a folding roll in which the tip of a folding plate fixed in the axial direction protrudes radially from the circumferential surface, and a folding roll in which the tip edge of the folding plate protrudes in the axial direction. The folding rolls having grooves on their circumferential surfaces are rotated in synchronization with each other, and the folding element of the sheet supplied between the two rolls is pushed into the groove of the folding roll with the tip of the folding plate. In a sheet folding method in which a crease is formed in a sheet using The circumferential speed of the tip of the folding plate protruding from the circumferential surface of
It is characterized in that the circumferential speed at the depth at which the tip of the folding plate enters the deepest position inside the groove of the gripping roll is made equal.

<Function> In other words, the basic concept of the present invention is to set the width in the circumferential direction of the axial groove on the circumferential surface of the gripping roll to twice the sheet thickness and the folding width that protrudes from the circumferential surface of the folding roll. Create a crease by matching the thickness of the leading edge of the sheet and pushing the sheet's crease in place into this groove with the leading edge of the folding board. Even when the sheet is taken out, the fold is caught in the groove, and the folding operation is completed by bringing the two wings of the fold of the sheet together.

In order to allow the tips of the folding plates in the axial direction that protrude radially from the circumferential surface of the folding rolls to enter and exit without any trouble into the grooves of the gripping rolls, which have such a narrow width, in this invention, both rolls Rather than making the circumferential speed of the outer circumferential surface of The circumferential speed of As a result, even if the tip of the folding plate, which enters the inside of the groove as both rollers rotate, momentarily becomes a hard fit with the inner wall of the groove at the deepest position, the circumferential speed of both rollers is equal at that point, so the folding plate cannot be folded. The tip of the plate is not damaged. The fold of the sheet firmly pressed against the groove wall by this instantaneous fit [1]
Even if the tip of the folding plate starts to withdraw at the next moment, the fold will not stick to the groove because the elastic compressive stress generated inside the sheet pushes the inner wall of the groove and increases the friction between the sheet and the groove wall. It is obtained and remains.

<Embodiment> Fig. 1.2 shows an embodiment of a sheet folding device to which the present invention is applied. In the figure, S denotes a sheet that is fed flatly by being sandwiched from above and below by, for example, a belt conveyor from the left side of the figure, and a feeding device and a cutting device are located on the left side of the figure. 1 is a gripping roll, 2 is a groove in its axial direction, and 3 is a folding plate. The base of the folding plate 3 fixed to the folding roll 4 has a tightening member screwed to the axial notch step of the folding roll 4. 5, and the tip 3' protrudes in the radial direction from the outer peripheral surface of the roll 4 by 2.5 to 3.0 mm in this example (
(See Figure 3). The gap between the gripping roll 1 and the folding roll 4 is approximately 0.5 to lam.

The groove 2 of the gripping roll 1 is formed by screwing a groove width adjusting member 6 to a similar axial notch step. Each time the thickness of the sheet to be folded changes, the above member is replaced so that the width of the groove in the circumferential direction matches the sum of twice the thickness of the sheet and the thickness of the tip of the folding plate.

As can be clearly seen in FIG. 2, the gripping roll l also has a deep annular groove 8 cut into its circumferential surface, into which the left and right take-out belts 7a are hung. The depth is such that there is no risk of touching the belt 7a or the tip of the folding plate 3.

The take-out belt 7a passes from the left and right deep grooves 8 to the grooves of the parallel rolls 9, respectively. The guide belt 7b, which constitutes the delivery belt mechanism 7 together with the take-out belt 7a and moves both wings of the sheet fold So together, is a roll pulley 11.
It is hung between 11 and 11. S' shown by a chain line in FIG. 1 shows a state in which the sheet S shown by a solid line is folded in half, is sandwiched between both belts 7a and 7b of the delivery belt mechanism 7, and then proceeds to the next step.

In FIG. 4, the gripping roll 1 and the folding roll 4 rotate synchronously, and the tip 3' of the folding plate 3 gradually pushes the sheet S into the groove 2. After being pushed in about On+s, the tip 3' of the folding plate 3 is gradually pulled out of the groove 2, and the fold S of the sheet remaining in the groove 2 is shown.
0 or about 90 degrees and is pushed out by the straight part of the take-out belt 7a, and the delivery belt mechanism 7, that is, the take-out and guide belt 7
The picture shows how the seat S is sandwiched between seats a and 7b, and behind them, both wings of the seat S come together and are in a folded state.

Approximately 2.5~:1. Since the circumferential speed of the tip of the protruding folding plate 3 is made equal to the sheet feeding speed, when the sheet S is pushed into the groove 2, it has the effect of pulling the sheet S by the pushing amount, eliminating loosening during traveling. When it is pushed in enough, the relationship between the fold line and the cut edge can be made accurate by activating the cutting machine on the left side of the IA.

Also, from the distance l1l (radius) R1 between the tip of the folding plate 3 and the axis of the folding roll 1 and the depth at which the tip of the folding plate enters the deepest inside the groove 2, the biting roll 1
With the distance (radius) 112 from the axis of
Make the circumferential speeds at 2 the same. Further, the folding plate 3 may have a different thickness up to the tip, but if the tip 3' that enters the groove 2 is made thinner as shown in FIG. This is preferable because it smoothly enters into the groove, pushes the sheet, and then exits from the groove without difficulty.

In this embodiment, since a sheet of napkin paper with a thickness of 0.25 mm is folded, the folding plate 3 made of thin steel plate has a thickness of 0.5 mm.
mm, the tip part 3' protruding from the outer periphery of the folding roller
The thickness was gradually reduced toward the tip, and the thickness at the tip was 0.3 mm. Good results were obtained by setting the circumferential width of the groove 2 of the gripping roll to 0.8 mm.

Figures 1 to 4 are examples of folding divided sheets.
FIG. 5 shows an example in which this invention is applied to continuous zigzag folding of a long sheet.

Both of the same-shaped rolls 10 and 10, which rotate synchronously while sandwiching the classic long sheet S, are the gripping rolls having the grooves 2 of the present invention, and at the same time, the folding plate 3 is attached to the opposite side so that they can also function as folding rolls. do. The roles change every half turn, and the direction of the fold S0 is reversed. The roll 10 on the side that has caught the fold s0 in the groove 2 rotates the fold S0 downward, but at the moment when the rear of the sheet is caught in the narrow groove 2 of the opposite roll 10, Crease S that was bitten first. falls off the groove 2 and folds downwards as shown in the figure, and this action is repeated alternately on the left and right sides.

It goes without saying that the sheet folding method of the present invention can be varied and applied in a variety of ways according to the well-known techniques of those who carry out the method without changing its gist.

<Effects of the Invention> This invention feeds a flat sheet between a folding roll in which the tip of a folding plate fixed in the axial direction from the circumferential surface protrudes radially and a gripping roll having thin grooves on the circumferential surface, and folds the sheet. By using a simple method of shallowly pushing the folding element of the sheet into the groove using the tip of the plate, we were able to create the fold and at the same time, we succeeded in making it bite. has become unnecessary.

Then, by rotating the gripping roll biting the narrow groove of the fold to a certain extent, the sheet can be pulled out from the narrow groove of the fold by turning it from the side to the bottom without fear of it coming out. From opposite directions, they both follow the crease and come together. Therefore, the folds can be folded as they are by letting the folds escape from the narrow grooves as shown in Figure 5, or the delivery and folding can be ensured using a delivery belt mechanism as shown in Figure 1. can be maintained and implemented in a variety of ways.

In addition, if the circumferential width of the groove of the gripping roll of this invention is adapted to the sum of twice the sheet thickness and the thickness of the tip of the folding plate that protrudes outward from the outer peripheral surface of the folding roll. does not necessarily mean matching, but also includes making the width of the groove a little narrower if the sheet is thick and compressible, for example.

[Brief explanation of the drawing]

FIG. 1 is a front view of an apparatus according to an embodiment of the present invention. Fig. 2 is a side view of Fig. 1, Fig. 3 is an enlarged view of the main part of Fig. 1, and Fig. 4 shows that after the folding plate of the folding roll gradually pushes the sheet into the groove of the gripping roll FIG. 5 is an explanatory diagram of another embodiment. In the figure, l is the gripping roll, 2 is the groove, 3 is the folding plate, 3' is the tip, and 4 is the A folding roll is shown. Procedural formalization (voluntary) October 29, 1988

Claims (1)

[Scope of Claims] A folding roll in which the tip of a folding plate fixed in the axial direction protrudes radially from the circumferential surface, and a gripping roll having an axial groove on the circumferential surface into which the tip edge of the folding plate enters. A sheet folding method in which a fold is formed in the sheet by rotating the sheets facing each other synchronously and pushing the expected fold position of the sheet supplied between the two rolls into the groove of the gripping roll with the tip of the folding plate. In this case, the width of the groove in the circumferential direction of the gripping roll is adjusted to the sum of twice the sheet thickness and the thickness of the tip of the folding plate, and the tip of the folding plate protrudes from the circumferential surface of the folding roll. and a circumferential speed at a depth at which the tip of the folding plate enters and is located at the deepest point inside the groove of the gripping roll are made equal.