JPH10296885A - Corrugated board folding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a corrugated board folding device for forming a folded corrugated board, which improves folding precision of a corrugated board, and quality of a corrugated box formed by the corrugated board. SOLUTION: A corrugated board folding device conveys a corrugated board 1 applied ruled lines, and folds each folding piece formed on both sides of the corrugated board 1 along the ruled lines during conveying. The device provided with folding processing means 5a and 5b, and 21a and 21b, which bend and fold each folding piece, a side roller 16, which butts each folding piece to both sides of the folded corrugated board 1, and a sheet guiding means 3, which guides each folding piece folded through the folding processing means 5a and 5b, and 21a and 21b. The sheet guiding means 3 is arranged to butt to the end of each folding piece which is folded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrugated cardboard sheet folding apparatus which forms a folded corrugated cardboard sheet after forming a corrugated cardboard sheet along a ruled line after applying a crease processing to the corrugated cardboard sheet.

[0002]

2. Description of the Related Art Conventionally, cardboard boxes have been used for printing,
2. Description of the Related Art A corrugated cardboard sheet folding device is provided which, after processing such as creases, slotter grooves and punching, folds a corrugated cardboard sheet along the creases to form a folded cardboard sheet. As shown in FIG. 10, the corrugated cardboard sheet folding device includes a slotter creaser (not shown) and a corrugated cardboard sheet bending section 40 that folds the corrugated cardboard sheet 1 along a ruled line K to form the folded corrugated cardboard sheet 1. It is composed.

Here, the slotter cleaner is disposed upstream of the cardboard sheet bending section 40, and performs processing on the cardboard sheet 1 such as two ruled lines K and slotter grooves S along the conveying direction. . The slotter cleaner includes two pairs of upper and lower ruled rollers arranged in parallel in a direction perpendicular to the transport direction. Here, the pair of upper and lower ruled line rollers is composed of an upper ruled line roller and a lower ruled line roller, and the lower ruled line roller is formed with one convex portion. The corrugated cardboard sheet 1 is introduced and held between them, and the corrugated cardboard sheet 1 is subjected to a process of forming a ruled line K.

The corrugated cardboard sheet 1 is subjected to a process of inserting the ruled line K (ruled line processing).
, And bent pieces 2a and 2b are formed at both ends of the central portion of the sheet. As shown in FIG. 10, the corrugated cardboard sheet bending section 40 supports the corrugated cardboard sheet 1 and functions as a ruler when folding the folded pieces (corrugated cardboard panel) 2a, 2b of the corrugated cardboard sheet 1 along the ruled line K. Sheet guides 20a and 20b, and these sheet guides 20a and 20b
0b, the conveyor belts 17a and 17b for conveying the corrugated cardboard sheet 1, and the sheet guides 20a and 20b and the conveyor belts 17a and 17b.
17b, bending bars 21a, 21b that guide and bend the pieces (cardboard sheet panels) 2a, 2b of the corrugated cardboard sheet 1, and are disposed downstream of the folding bars 21a, 21b. And folding belts 5a and 5b which are pushed up and folded while guiding the bent pieces 2a and 2b of the cardboard sheet 1.

Here, the transport belts 17a and 17b are
It is wound around transport rollers 17c and 17d, and is driven to rotate by these transport rollers 17c and 17d. The bending bars 21a and 21b are arranged so as to be inclined so that the positions in the height direction and the width direction gradually change along the sheet conveying direction, and while guiding the bending pieces 2a and 2b of the cardboard sheet 1, It gradually bends.

Further, the folding belts 5a and 5b are also arranged so as to be inclined so that the positions in the height direction and the width direction gradually change along the sheet conveying direction. The guide 2b is gradually folded while being guided, and the bent piece 2b is bonded to the bent piece 2a via the glued piece 6 formed at the end thereof.

When the folded pieces 2a and 2b of the corrugated cardboard sheet 1 are folded by the folding belts 5a and 5b, both ends of the corrugated cardboard sheet 1 are in sliding contact with side rollers (not shown) and are pressed by these side rollers. It is supposed to be. In FIG. 10, the state in which the folded pieces 2a and 2b of the corrugated cardboard sheet 1 are being folded is indicated by a two-dot chain line and a solid line, and the arrow in the figure indicates the direction in which the sheet is folded.

As shown in FIG. 10, the corrugated cardboard sheet 1 on which the ruled line K and the slotter groove S have been processed by the slotter cleaner is provided in such a state that the bent pieces 2a and 2b are horizontal. 20b and the transfer belts 17a and 17b,
Due to the conveying force of 7a and 17b (frictional force generated between the cardboard sheet and the conveying belt), the sheet is sequentially transferred to the downstream side. At this time, the folded pieces 2a,
2b is guided while slidingly contacting the folding bars 21a and 21b, and the sheet guide 20 functioning as a ruler is provided.
It is bent at the position of the ruled line K along a and 20b.

The folded pieces 2a and 2b of the corrugated cardboard sheet 1 thus folded are further gradually folded while being in sliding contact with the folding belts 5a and 5b, and the folded piece 2b is glued at its end. The folded corrugated cardboard sheet 1 is bonded to the folded piece 2a via the piece 6 to form a folded corrugated cardboard sheet 1 as shown in FIG. In FIG. 9, K is a ruled line, and S is a slotter groove.

When the bent piece 2b is bonded to the bent piece 2a via the glued piece 6 formed at the end, slotter grooves S are formed on both sides of the glued piece 6. The corrugated cardboard sheet 1 folded in this way is transferred to the downstream side and stacked.

[0011]

However, in such a conventional corrugated cardboard sheet folding apparatus, the corners of the sheet guides 20a and 20b functioning as rulers are applied along the ruled line K of the corrugated cardboard sheet 1. The bent bars 21a and 21b and the folding belts 5a and 5b are used to fold the bent pieces 2a and 2b of the corrugated cardboard sheet 1 from the horizontal state by approximately 180 °. The bent portions are shown in FIG. As described above, the lower liner 22a of the main body of the corrugated cardboard sheet 1 and the liner 22b of the bent piece 2b to be overlapped with the liner 22a collide with each other. You will crush the liner.

That is, when the liner 22a on the lower side of the main body of the corrugated cardboard sheet 1 is more easily crushed, as shown in FIG. 11B, the position of the ruled line K is located above the liner joining surface. When the liner 22b of the bent piece 2b is more easily crushed, as shown in FIG. 11C, the position of the ruled line K is lower than the liner joint surface. In this case, since the length of the corrugated cardboard sheet 1 in the horizontal direction (the horizontal direction in the drawing) is regulated by the side rollers 16, 16, the position of the ruled line K is changed to the liner joining surface as shown in FIG. If it is higher than the bent pieces 2a and 2b of the cardboard sheet 1,
The gap of the slotter groove S formed at both ends of the glued portion becomes wider as shown by Pa in FIG.
As shown in (c), when the position of the ruled line K is below the liner joining surface, the folded piece 2 of the corrugated cardboard sheet 1 is used.
The gaps of the slotter grooves S formed at both ends of the glued portions a and 2b become narrow as indicated by Pb in the drawing.

When the gap of the slotter groove S is widened or narrowed as described above, the overlapping portion of the glued piece 6 formed at the end of the bent piece 2b becomes large or small. When the corrugated cardboard sheet 1 is formed into a box shape, the corrugated cardboard sheet 1 becomes distorted, its strength is remarkably reduced, and its appearance is deteriorated. Also, if the position of the ruled line K is above or below the liner joining surface, the bent portion of the corrugated cardboard sheet 1 may be curved.
When the is made into a box shape, the strength is reduced, and the quality is remarkably reduced.

In order to cope with such an inaccuracy of the bent portion of the corrugated cardboard sheet 1, it is conceivable to perform the crease processing by crushing the corrugated cardboard sheet 1 with a stronger pressing force in the crease processing of the slotter cleaner (not shown). However, crushing the corrugated cardboard sheet 1 with such a strong pressing force is not preferable because the liner may be broken (cracked) or the like.

The folding of the folded pieces 2a and 2b (see FIG. 9) and the bonding of the glued piece 6 and the folded piece 2a of the folded piece 2b are performed by transporting the corrugated cardboard sheet 1 by the transport belts 17a and 17b. As a result, the folded piece 2a and the folded piece 2b cannot be securely bonded to each other, and as shown in FIG. 12, the upper and lower portions of the folded corrugated cardboard sheet 1 move in the transport direction. There is also a problem that they may be stuck back and forth and bonded together, and the quality thereof is significantly reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is intended to improve the folding accuracy of a corrugated cardboard sheet and improve the quality of a corrugated cardboard box in which a corrugated cardboard sheet is formed into a box. It is intended to provide a device.

[0017]

According to the first aspect of the present invention, a corrugated cardboard sheet folding apparatus according to the present invention forms a corrugated cardboard sheet on both sides of a corrugated cardboard sheet along a ruled line while conveying the corrugated cardboard sheet. In a corrugated cardboard sheet folding apparatus for folding each folded piece into a folded state, a folding means for folding and folding each of the above-mentioned folded pieces, and abutting on both sides of the corrugated cardboard sheet in a state where each of the above-mentioned folded pieces is folded. A side roller, and sheet guide means for guiding each of the bent pieces folded by the bending means, such that the sheet guide means is brought into contact with an end of each of the folded pieces in the folded state. It is characterized by being arranged.

According to a second aspect of the present invention, there is provided a cardboard sheet folding apparatus according to the first aspect, further comprising sheet conveying means having an engaging portion for conveying the folded cardboard sheet. However, the speed is controlled so as to engage with the rear end of the folded cardboard sheet. The corrugated cardboard sheet folding device according to the present invention according to Claim 3 is the device according to Claim 1 or 2, further comprising a pair of crease rolls, and a slotter cleaner for performing the crease processing on the corrugated cardboard sheet by the crease rolls. At least one of the pair of ruled rolls of the slotter cleaner has a plurality of convex portions for the ruled lines.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 show a cardboard sheet folding apparatus according to an embodiment of the present invention. The cardboard sheet folding apparatus according to the present embodiment is provided in a cardboard box machine, and a cardboard sheet 1 in a folded state by folding a cardboard sheet 1 along a ruled line K as shown in FIG. And a corrugated sheet bending section 40 that forms

Here, the slotter cleaner is disposed on the upstream side of the cardboard sheet bending section 40 and processes the corrugated cardboard sheet 1 such as the ruled line K and the slotter groove S along the conveying direction. The slotter cleaner includes two pairs of upper and lower ruled rollers arranged side by side in the sheet width direction. Here, a pair of upper and lower ruled line rollers
As shown in FIG. 8, an upper ruled roller 19a and a lower ruled roller 19b are provided, and a plurality of (here, two) convex portions 19c, 19 are provided on the outer peripheral surface of the lower ruled roller 19b.
The cardboard sheet 1 is introduced and caught between the upper ruled roller 19a and the lower ruled roller 19b, and a plurality of lines (here, two lines) are formed at bent portions of the cardboard sheet 1. (Ruled line processing) for inserting the ruled line K.

By applying the ruled line processing, the corrugated cardboard sheet 1 is partitioned by the ruled line K, and bent pieces 2a and 2b are formed at both ends. As shown in FIG. 1, the corrugated cardboard sheet bending section 40 includes transport belts 17a and 17b, bending bars (bending means) 21a and 21b, folding belts (bending means) 5a and 5b, side rollers 16, 16, a sheet bonding section guide (sheet guiding means) 3, and a sheet conveying device (sheet conveying means) 4.

Here, the transport belts 17a and 17b are
The cardboard sheet 1 is brought into contact with the upper surface of the cardboard sheet 1
Is transported. Folding bars 21a, 21b
Is disposed below the conveyor belts 17a and 17b, and is bent while guiding the bent pieces (corrugated cardboard panel) 2a and 2b of the corrugated cardboard sheet 1.

These bending bars 21a, 21b are
The corrugated cardboard sheet 1 is configured to be gradually bent while guiding the bent pieces 2a and 2b of the corrugated cardboard sheet 1 in such a manner that the positions in the height direction and the width direction are gradually changed along the sheet conveyance direction. ing. The folding belts 5a and 5b are disposed downstream of the folding bars 21a and 21b, and are foldable so that the folding pieces 2a and 2b of the cardboard sheet 1 are pushed up while being guided.

These folding belts 5a and 5b are also
The corrugated cardboard sheet 1 is configured to be gradually folded while guiding the bent pieces 2a and 2b of the corrugated cardboard sheet 1 so that the position in the height direction and the width direction is gradually changed along the sheet conveyance direction. ing. Side rollers 16,
When the folding pieces 2a and 2b are folded by the folding belts 5a and 5b, the cardboard sheet 1
Are pressed while slidingly contacting both side ends.

The sheet bonding portion guide 3 guides the bent pieces 2a and 2b of the cardboard sheet 1. The sheet conveying device (sheet conveying means) 4 is disposed above the downstream side of the sheet bonding guide 3 and conveys the folded cardboard sheet 1. In FIG. 1, 30
Is a width direction moving frame. The arrow in FIG. 1 indicates the transport direction, and the cardboard sheet 1 is transported on a sheet path line.

Further, like the conventional corrugated cardboard sheet folding apparatus, the present corrugated cardboard sheet folding apparatus also has
Sheet guides 20a and 20b (see FIG. 10) which support the corrugated cardboard sheet 1 and which serve as rulers when folding the folded pieces (corrugated cardboard panel) 2a and 2b of the corrugated cardboard sheet 1 along the ruled line K are also provided. It is arranged so as to face below the sheet guides 20a and 20b.

Next, the sheet bonding portion guide 3 which is a feature of the present embodiment will be described with reference to FIGS. The sheet bonding portion guide 3 is formed by folding the corrugated cardboard sheet 1 using the folding belts 5a and 5b.
In the step of folding the folded pieces 2a and 2b and the initial step of bonding the ends of the folded pieces 2a and 2b of the cardboard sheet 1, the folded pieces 2a and 2b are gradually folded when the folded pieces 2a and 2b of the cardboard sheet 1 are gradually folded. It is for guiding.

The sheet bonding portion guide 3 has a main body portion 3a for guiding one bent piece 2b of the corrugated cardboard sheet 1 to be folded by the folding belt 5b, as shown in a schematic perspective view partially broken away in FIG. A stopper portion 8 provided integrally above the main body portion 3a and holding the folded piece 2b to be folded at a predetermined height position so as not to escape upward; and a stopper portion 8 integrally formed on the downstream side of the stopper portion 8. The guide plate 3c and the side surface of the main body 3a.
L for guiding the other bent piece 2a of the cardboard sheet 1
And a shape guide portion 3b. In FIG. 2, Z
Is a broken part.

Here, the main body 3a has, at its upper end, a bent piece 2b which is folded by the folding belt 5b.
The L-shaped stepped portion 3d is formed so as to be gradually inclined upward according to the bending state of the bent piece 2b so as not to interfere with the ends of the L-shaped stepped portion 3d and the stopper portion 8 The groove 9 for guiding the bent piece 2b
Are formed.

The L-shaped step 3d of the main body 3a has
A projection 10 is formed so as to protrude inside the groove 9. The projection 10 supports the bent piece 2 b, and the glued piece 6 of the bent piece 2 b supplied with the glue 7 is attached to the main body 3 a.
Is guided without contacting the L-shaped step portion 3d. The guide plate portion 3c is formed with a stepped portion 3e so as to restrict a displacement of one bent piece 2b supported by the projection 10 formed on the main body portion 3a in the horizontal direction.

The sheet bonding portion guide 3 thus configured is disposed at a position where the ends of the bent pieces 2a and 2b come into contact with each other in a state where the bent pieces 2a and 2b are folded. The cage (see FIG. 4 (d)) restricts the horizontal displacement that occurs when the bent pieces 2a and 2b are folded. That is, the end of the bent piece 2b abuts on the side surface of the L-shaped stepped portion 3d constituting the groove 9 at the time of folding, so that the horizontal displacement that occurs at the time of folding does not occur. Is in contact with the side surface of the main body 3a at the time of folding, so that there is no horizontal displacement occurring at the time of folding.

As shown by the dashed line in the schematic side view of FIG. 3, the folded piece 2a of the corrugated cardboard sheet 1 is gradually bent to form the folded corrugated cardboard sheet 1. Transferred downstream. In other words, at the section AA of FIG. 3 of the sheet bonding section guide 3, as shown in FIG. 4A, while the corrugated cardboard sheet 1 is being conveyed by the conveying belt 17, one of the bent pieces 2 b is The folding belt 5b precedes the other bending piece 2a so that the bending angle θ of the one bending piece 2b becomes smaller before the other bending piece 2a.
Is folded by The bent piece 2a is folded by the folding belt 5b.

In this case, since the groove 9 is formed above the sheet bonding section guide 3, the bent piece 2b is folded without interfering with the main body 3a. In FIG. 4A, reference numeral 13 denotes a frame. next,
FIG. 4 shows a portion of the sheet bonding portion guide 3 viewed from the arrow BB in FIG.
As shown in (b), the end of one of the folded pieces 2b of the corrugated cardboard sheet 1 is provided so as to be gradually positioned upward according to the folded state of the folded piece 2b while being folded by the folding belt 5b. The main body 3a is guided above the main body 3a along the L-shaped step 3d of the main body 3a, and is housed in a groove 9 formed by the L-shaped step 3d of the main body 3a and the stopper 8.

In this case, the end of the bent piece 2b abuts on the side surface of the main body 3a, so that the folded piece 2b can be correctly folded without being displaced in the horizontal direction when folded. The bent piece 2b is supported by a projection 10 formed on the main body 3a so that the glued piece 6 coated with the glue 7 does not contact the main body 3a. Next, as shown in FIG. 4C, in the sheet bonding portion guide 3 viewed along the line CC, one of the bent pieces 2b of the corrugated cardboard sheet 1 folded by the folding belt 5b is, as shown in FIG. The end is sandwiched between the stopper 8 and the projection 10. On the other hand, the other bent piece 2a of the cardboard sheet 1 is guided along the upper surface of the L-shaped guide portion 3b, and is folded by the folding belt 5a.

In this case, the cardboard sheet 1 to be folded
Are pressed by the side rollers 16, 16,
The folded corrugated cardboard sheet 1 is regulated so as not to be displaced in the horizontal direction. Also, one bent piece 2b
Is in contact with the side surface of the L-shaped step portion 3d of the main body portion 3a, and can be correctly folded without causing a horizontal displacement when the folded piece 2b is folded.

Next, the sheet bonding portion guide 3 shown in FIG.
4D, one bent portion 2b is sandwiched between the guide plate 3c and the upper end portion of the main body portion 3a, and the other bent portion 2 is viewed as shown in FIG.
a is guided above the main body 3a by a guide part 3b provided so as to be gradually higher according to the folded state of the bending part 2a, and a guide plate 3c provided at the upper end of the main body 3a. Abuts between the guide plate 3c and the guide portion 3b.

In this case, the end of one of the bent pieces 2b abuts on the step 3e formed on the guide plate 3c, so that the folded piece 2b can be correctly folded without causing a horizontal displacement when the folded piece 2b is folded. In the folded state, the end of the other bent piece 2a abuts against the side surface of the main body 3a, and the folded piece 2a is correctly folded without causing a displacement in the horizontal direction when the folded piece 2a is folded. The overlapping state (overlapping dimension) of the glued piece 6 of 2b and the end of the other bent piece 2a is accurately adjusted and bonded. Thereby, the bonding accuracy at the time of folding the bent pieces 2a and 2b can be improved.

Next, the sheet conveying device 4 which is a feature of the present embodiment will be described with reference to FIGS. The sheet conveying device 4 is disposed on the downstream side of the present corrugated cardboard sheet folding device and above the sheet path line, and assists the conveyance of the folded cardboard sheet 1.

As shown in the schematic cross-sectional view of FIG. 5, the sheet conveying device 4 includes two sets of timing belts 12, 12 arranged in the width direction of the sheet. Synchro pulley 11a,
11b. As shown in FIG. 5 and FIG.
A plurality of claw portions (engaging portions) 15 are fixed to the outer peripheral surface at a pitch (interval) corresponding to the circumferential length of the printing cylinder in the previous process. Then, the claw portions 15 fixed to the timing belts 12 and 12 are engaged with the rear end of the folded cardboard sheet 1, and the upper and lower portions of the folded cardboard sheet 1 are separated. The cardboard sheet 1 is conveyed so as not to be displaced.

The synchro pulleys 11a and 11b are
Each is supported by frames 13, 13 via bearings, and is driven by servomotors 14, respectively. Two sets of timing belts 12, 1 are provided.
2 runs synchronously. As shown in FIGS. 6 and 7, these timing belts 12, 12 have pawl portions 15 fixed to the timing belts 12, 12.
Is temporarily decelerated at a position immediately before engaging with the corrugated cardboard sheet 1, and the servo tube 14 is driven by the feedback of the detection signal of the rear end portion of the corrugated cardboard sheet 1 by the photoelectric tube 18 to accelerate the outer periphery of the timing belt 12. The claw portion 15 fixed to the surface is engaged with the trailing end of the corrugated cardboard sheet 1 to be conveyed, and after the engagement, the corrugated cardboard sheet 1 is conveyed at the same speed for a predetermined time (see FIG. 7). Has become. Such speed control is repeatedly performed each time the cardboard sheet 1 is carried in.

Specifically, the timing belts 12, 12
As shown in the velocity diagram of FIG. 7, the speed of the claw portion 15 fixed to each of the positions X, Y,
At O, the speed is controlled to be slower and then faster, and at other positions the speed is controlled to be faster than the speed of the conveyor belt. In order to adjust the timing of the claw portion 15 of the timing belt 12 to the rear end of the corrugated cardboard sheet 1, the rotation shaft of the upstream synchronous pulley 11a around which the timing belts 12 and 12 are wound and the downstream synchronous pulley 11a Distance from the rotation axis (Fig. 6
Is set to an integral multiple of the printing cylinder circumference in the previous step.

The corrugated cardboard sheet folding apparatus according to the present embodiment operates as follows because it is configured as described above. That is, as shown in FIG. 1, the corrugated cardboard sheet 1 on which the ruled line K and the slotter groove S have been processed by a slotter cleaner (not shown) is placed in such a state that the bent pieces 2a, 2b are horizontal, and the sheet guides 20a, It is introduced into the gap between the transfer belts 20b and the transfer belts 17a and 17b, and is sequentially transferred to the downstream side by the transfer force of the transfer belts 17a and 17b (frictional force generated between the corrugated cardboard sheet and the transfer belt). At this time, the upper surfaces of the bent pieces 2a and 2b of the corrugated cardboard sheet 1 are bent at the positions of the ruled lines K along the sheet guides 20a and 20b functioning as rulers (not shown) while slidingly contacting the bending bars 21a and 21b.

The folded pieces 2a and 2b of the corrugated cardboard sheet 1 thus folded are further gradually folded while slidingly contacting the folding belts 5a and 5b.
The folded cardboard sheet 1 is formed. When the corrugated cardboard sheet 1 is conveyed as described above, FIG.
As shown in (a) to (d), the bent piece 2b of the corrugated cardboard sheet 1 is the L of the main body 3a of the sheet bonding section guide 3.
The cardboard is guided along the stepped portion 3d, and abutted against the side surface of the L-shaped stepped portion 3d so as not to be displaced in the horizontal direction at the time of folding. The bent piece 2b of the sheet 1 is guided along the L-shaped guide portion 3b of the sheet bonding portion guide 3,
The folding belt 5a is accurately folded by the folding belt 5a in a state in which the lateral displacement of the folding part 5a does not occur due to contact with the side surface of the main body part 3a. The overlapping state (overlapping dimension) is accurately adjusted and bonded.

The folded corrugated cardboard sheet 1 is conveyed with its rear end engaged with the claw portions 15 fixed to the timing belts 12, 12 of the sheet conveying device 4 disposed downstream. Is done. For this reason, there is no displacement between the upper part and the lower part, and the accuracy of the parallel and right-angled portions when the corrugated cardboard sheet 1 is box-shaped can be maintained.

Thereafter, the corrugated cardboard sheet 1 folded in this manner is transferred to a downstream downstream step and stacked. Therefore, according to the cardboard sheet folding device of the present embodiment, when the cardboard sheet 1 is folded,
In a state where the corrugated paperboard sheet 1 is regulated so as not to be displaced in the horizontal direction by the side rollers 16, 16, the sheet bonding portion guide 3 allows the corrugated paperboard sheet 1 to be bent in the horizontal direction when the folded pieces 2 a and 2 b are folded. Since the displacement is regulated so as not to occur, the position of the ruled line K at the bent portion of the corrugated cardboard sheet 1 may be higher, lower, or even curved than the liner joint surface. The glued piece 6 of the bent piece 2b and the bent piece 2a
, The width of the slit groove S of the bonding portion can be formed accurately, and the folding accuracy of the bent pieces 2b and 2a can be improved. There is an advantage that a high-quality cardboard box having various dimensions and shapes can be formed.

Further, since the folds of the corrugated cardboard sheet 1 can be formed linearly and reliably, the strength of the corrugated cardboard box can be greatly improved. Therefore, depending on the application, the liner may be changed to a thin liner or poor quality base paper. You can also
Resources can be saved and manufacturing costs can be reduced. Also,
The appearance during the molding of the cardboard box is improved, and the aesthetic quality of the product is improved.

Further, the folded corrugated cardboard sheet 1 is speed-controlled so that the claw portion 15 fixed to the timing belt 12 of the sheet conveying means 4 is engaged with the rear end of the corrugated cardboard sheet 1 and folded. The corrugated cardboard sheet 1 in the opened state is transferred to the sheet conveying means 4 whose speed is thus controlled.
The upper and lower portions of the corrugated cardboard sheet 1 are not displaced back and forth with respect to the transport direction because the paper is conveyed by engaging with the claw portion 15 fixed to the timing belt 12 of FIG. There is also an advantage that the glued piece 6 of 2b and the bent piece 2a can be securely stuck together at an accurate position, and distortion at the time of assembling the cardboard box can be eliminated.

Also, in the corrugated cardboard sheet folding apparatus of the present embodiment, the lower ruled line roller 19b of the slotter cleaner is used.
Are provided with a plurality of (here, two) projections 19c,
19c are formed, and a plurality of (two in this case) ruled lines K are formed in the bent portions of the corrugated cardboard sheet 1, so that the bent pieces 2a and 2b of the corrugated cardboard sheet 1 are formed. There is an advantage that flexibility in the ruled line width direction can be provided at the fold position at the time of folding and folding, so that the accuracy of the folded dimension of the cardboard sheet 1 can be further improved.

Although the sheet conveying device 4 is provided above the sheet path line in the cardboard sheet folding apparatus of the present embodiment, it may be provided below the sheet path line. Further, in the corrugated cardboard sheet folding device of the present embodiment, the engaging portion of the sheet conveying device 4 is configured as the claw portion 15, but the present invention is not limited to this, and the engaging portion engages with the folded cardboard sheet 1. Anything that can be done is acceptable.

Further, in the corrugated cardboard sheet folding apparatus according to the present embodiment, the speed of the sheet conveying apparatus 4 is temporarily reduced and then accelerated, and the corrugated cardboard sheet 1 in a state where the claw portions 15 of the sheet conveying apparatus 4 are folded is provided. The speed control of the sheet conveying device 4 is not limited to this, but the rear end portion of the corrugated cardboard sheet 1 in a state where the claw portions 15 of the sheet conveying device 4 are folded. What is necessary is just to be able to make it engage with.

Further, in the corrugated cardboard sheet folding apparatus of the present embodiment, the sheet bonding section guide 3, the sheet conveying apparatus 4
And the ruled line roll of the slotter cleaner is configured as having a plurality of convex portions. For example, the ruled line roll of the slotter cleaner is configured to include only the sheet bonding portion guide 3 and the ruled line of the slotter cleaner is formed. Roll 1
You may comprise as what has a convex part of a line,
The sheet laminating unit guide 3 and the sheet conveying device 4 may be provided, and the ruled line roll of the slotter cleaner may be configured to have one convex portion.

[0052]

As described above in detail, according to the cardboard sheet folding apparatus of the first aspect of the present invention, when the cardboard sheet is folded, the side rollers do not cause the horizontal displacement of the cardboard sheet. And the sheet guide means restricts the horizontal displacement that occurs when the folded piece of the corrugated cardboard sheet is folded, thereby improving the folding accuracy of the folded piece. Since the piece and the other bent piece can be accurately bonded to each other, and the width of the slit groove at the bonded portion can be formed accurately,
There is an advantage that a high quality cardboard box having a shape can be formed.

According to the second aspect of the present invention, the engaging portion of the sheet conveying means is speed-controlled so as to engage with the rear end of the corrugated cardboard sheet, and the corrugated cardboard in the folded state. Since the sheet is conveyed by engaging the engaging portion of the sheet conveying means whose speed is controlled in this way, the upper portion and the lower portion of the corrugated cardboard sheet may be shifted back and forth in the conveying direction. Therefore, there is an advantage that one bent piece and the other bent piece can be securely bonded to each other at an accurate position and distortion at the time of assembling the cardboard box can be eliminated.

According to the third aspect of the present invention, a plurality of projections are formed on the outer peripheral surface of the crease roller of the slotter creaser, and the corrugated cardboard is formed by the plurality of projections. Since the sheet is processed with a plurality of ruled lines, the folded pieces of the corrugated cardboard sheet can be bent, and the fold position at the time of folding can be flexibly arranged in the crease width direction, and the folding accuracy of the corrugated cardboard sheet can be further improved. Thereby, there is an advantage that a higher quality cardboard box can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing the entire configuration of a cardboard sheet folding apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a sheet bonding portion guide of the cardboard sheet folding apparatus according to one embodiment of the present invention.

FIG. 3 is a schematic side view showing a sheet bonding portion guide of the cardboard sheet folding device according to one embodiment of the present invention.

FIG. 4 is a schematic view showing a sheet bonding portion guide of the cardboard sheet folding apparatus according to one embodiment of the present invention;
3A is a sectional view taken along the line AA in FIG. 3, and FIG.
FIG. 3B is a cross-sectional view taken along the arrow B. FIG.
FIG. 4D is a sectional view taken along line D-D in FIG. 3.

FIG. 5 is a schematic sectional view showing a sheet conveying device of the cardboard sheet folding device according to one embodiment of the present invention.

FIG. 6 is a schematic side view showing a sheet conveying device of the cardboard sheet folding device according to one embodiment of the present invention.

FIG. 7 is a velocity diagram of the sheet conveying device of the cardboard sheet folding device according to the embodiment of the present invention.

FIG. 8 is a schematic sectional view showing a slotter cleaner in a pre-process of the cardboard sheet folding apparatus according to one embodiment of the present invention.

FIG. 9 is a schematic perspective view showing the cardboard sheet in a folded state.

FIG. 10 is a schematic sectional view showing a conventional cardboard sheet folding apparatus.

11A and 11B are diagrams for explaining a problem in folding a corrugated cardboard sheet in a conventional corrugated cardboard sheet folding apparatus, wherein FIG. 11A is a schematic cross-sectional view of the corrugated cardboard sheet when folded, and FIG. FIG. 4C is a schematic cross-sectional view showing a state where the line is higher than the liner bonding surface, and FIG. 4C is a schematic cross-sectional view showing a state where the ruled line portion is lower than the liner bonding surface.

FIG. 12 is a schematic diagram for explaining a problem when a folded cardboard sheet is transported in a conventional cardboard sheet folding apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Corrugated cardboard sheet 2a, 2b Folded piece (corrugated cardboard panel) 3 Sheet bonding part guide (sheet guide means) 3a Main body part 3b L-shaped guide part 3c Guide plate part 3d L-shaped step part 3e Step part 4 Sheet conveying device (sheet) 5a, 5b Folding belt (bending means) 6 Glue piece 7 Glue 8 Stopper 9 Guide groove 10 Projection 11a, 11b Synchro pulley 12 Timing belt 13 Frame 14 Servo motor 15 Claw 16 Side roller 17a, 17b Transport Belts 17c, 17d Conveying rollers 18 Photoelectric tubes 19 Ruled line roll 19a Upper ruled line roll 19b Lower ruled line roll 19c Convex portions 20a, 20b Sheet guides 21a, 21b Bending bar (bending means) 22 Liner 30 Width moving frame 40 Corrugated cardboard Bent section

Claims (3)

[Claims] 1. A corrugated cardboard sheet folding apparatus for folding folded pieces formed on both sides of a corrugated cardboard sheet along a ruled line while conveying a corrugated cardboard sheet subjected to crease processing, wherein each of the folded pieces is Folding means for folding and folding, a side roller contacting both sides of the corrugated cardboard sheet in a state where each of the above-mentioned folded pieces is folded, and a sheet guide for guiding each of the above-mentioned folded pieces to be folded by the folding means. Means, and wherein the sheet guide means is disposed such that the ends of the folded pieces in the folded state are in contact with each other. 2. A sheet conveying means having an engaging portion for conveying the folded cardboard sheet, wherein the engaging portion engages with a rear end of the folded cardboard sheet. The cardboard sheet folding apparatus according to claim 1, wherein the folding is performed. 3. A slotter creaser having a pair of crease rolls for applying crease processing to the corrugated cardboard sheet by the crease rolls, wherein at least one of the pair of crease rolls of the slotter creaser is 3. The corrugated cardboard sheet folding device according to claim 1, wherein a plurality of projections for the ruled line are provided.