JPH0350699B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a corrugated board manufacturing apparatus, particularly to improvements in the upper and lower corrugating rolls and nip pressure rolls in a single facer.

In recent years, cardboard packaging boxes, which are made of paper, have become the main packaging material for small and medium-sized items due to their various advantages, such as their durability and ease of transportation.

In addition to speeding up the manufacturing process, conventional corrugated board manufacturing equipment requires corrugation processing of the core, and after gluing, the rolls must be heated to press them against the liner to speed up the drying of the glue and ensure complete adhesion. Iron rolls have been used due to the lack of availability. However, when these iron rolls are used, they sometimes emit high-pitched sounds exceeding 100 phons, which not only causes noise pollution to the neighborhood, but also causes vibrations, significantly deteriorating the working environment and making work difficult. There was a risk that this would lead to a decrease in efficiency and even lead to work-related accidents.

For this reason, conventional measures have been taken to reduce noise, such as covering the single facer that generates the noise or installing corrugated molded parts underground, but these methods require additional equipment costs, and It could not be a fundamental solution.

SUMMARY OF THE INVENTION An object of the present invention is to provide a single facer that can significantly reduce noise and vibration generation through slight modification without substantially changing the structure of the conventional single facer.

Another object of the present invention is to use a low-temperature adhesive and a corresponding material for one of the corrugating rolls to ensure corrugation of the paper core without heating the roll. To provide a single facer which can reduce the oscillation of a lower corrugating roll to prevent corrugated drift of the core, high-low and poor lamination, and enables the production of corrugated board sheets under energy-saving conditions.

The above-mentioned and other purposes include an upper roll and a metal lower roll for corrugating a strip-shaped paper core that is continuously fed, and a paper core that is fed separately from the corrugated paper core. In an apparatus having nip pressure rolls for press-bonding a band-shaped liner after applying a low-temperature adhesive, at least the entire stepped portion of the upper roll is formed of a polyurethane material, and at least the surface of the nip pressure roll is made of a polyurethane material. This is achieved by a single facer in corrugated board manufacturing, characterized in that the diameter of the lower corrugating roll is larger than the diameters of the upper corrugating roll and the nip pressure roll.

Next, preferred embodiments of the single facer according to the present invention will be explained with reference to the drawings.

Figure 1 schematically shows a single facer, where 1 is the machine frame body, 2 is the upper roll, 3 is the lower roll, 4 is the nip pressure roll, 5 is the glue roll, and 6 is the glue adhesion amount adjustment doctor. 7 is a glue reservoir, and 8, 9, and 10 are feed rolls.
In the apparatus shown in the figure, a strip-shaped paper core 11 passes through a feed roll 8 and passes through the meshing portion of an upper roll 2 and a lower roll 3, which rotate in opposite directions. Steps are formed into a shape that corresponds to the shape of the steps. Glue is applied to the corrugated paper core 11 at the contact portion between the lower corrugated roll 3 and the glue roll 5. On the other hand, the liner 12 sent through the feed roll 9 is pressed to the corrugating medium to which glue has been applied at the contact area between the lower roll 3 and the nip pressure roll 4.
It is sent to the next process through.

In such a device, the meshing portion between the upper roll 2 and the lower roll 3 and the contact portion between the lower roll 3 and the nip pressure roll 4 are the main sources of noise and vibration.

In the present invention, the stepped portion of the upper roll 2 is
It may be obtained by bonding a material made entirely of a polyurethane resin material (for example, Mitsui Nisso Urethane Co., Ltd. trade name "L-213") onto a steel roll using an adhesive. Furthermore, a casting method may be used in which a steel roll is placed in a mold and polyurethane resin is injected into the gap around the roll. The nip pressure roll 4 may be coated with a polyurethane material by coating a steel roll with a polyurethane resin (for example, the above trade name "L-213") or by bonding the roll with an adhesive.
Furthermore, a steel roll is placed in the mold, and polyurethane resin is injected into the gap around it.
A casting method may also be used. The thickness of the polyurethane layer is applied to the upper roll in a ratio of about 1:0.05 to 0.2 to the total diameter when processing the steps. In the nip pressure roll,
The thickness of the polyurethane layer is 1:0.02 to the total diameter.
Coated with a ratio of ~0.1. However, if the diameters of the upper roll and the nip pressure roll are formed to be significantly smaller than the diameter of the lower roll, the entire roll may be made of polyurethane resin.

When coating the upper roll and the nip pressure roll with a polyurethane layer by casting, at least one axial groove is formed on the surface of the iron roll to ensure a bond between the iron roll and the polyurethane. In Figures 2A and 2C, four vertical grooves 2b and 4b are formed on steel rolls 2a and 4a, respectively.
Polyurethane layers 2c and 4c are provided on the outer peripheral surface of the roll by a casting method. Further, a stepped portion 2d is formed on the upper roll 2 by machining. Although four grooves are formed in FIG. 2, the number of grooves can be selected as desired, and protrusions or recesses of other forms may be formed instead of vertical grooves. .

The polyurethane applied to the upper roll 2 and the nip pressure roll 4 is, for example, the above-mentioned product name “L-
In the case of ``213'', the hardness is 75D, but since the lower roll 3 is made of steel as in the past, no particular problem occurs in the step forming. however,
Polyurethane material is heat resistant (usable temperature is
(usually at 80°C to 90°C),
The glue used in the present invention is preferably a low-temperature adhesive (an adhesive that allows the core and liner to be bonded together without heating), for example, a synthetic resin agent typified by vinyl acetate.

The lower roll 3 used in the single facer of the present invention is made of steel, but has a larger diameter than the upper roll 2 and the nip pressure roll 4.
More specifically, the ratio of the diameters of the lower roll 3 and the upper roll 2 or nip pressure roll 4 is 1:0.8 to 0.5.
is preferred. In this way, a polyurethane layer 2a is formed on the surface of one of the rolls, especially the upper roll 2,
By forming the lower roll 3 to have a relatively large diameter and meshing them together, the generation of noise and vibration can be significantly reduced. Furthermore, since the steps on one of the rolls are made of a slightly elastic material, the engagement gap between the steps on both rolls can be reduced. In this way, in the present invention,
By making one part made of iron and the other part made of polyurethane, step forming of the core can be reliably performed. On the other hand, in the relationship between the lower roll 3 and the nip pressure roll 4, it is possible to similarly suppress the generation of noise and vibration at the contact portion.

In the illustrated embodiment, the ratio of the diameters of the lower roll 3 and the upper roll is 1:3/4, the lower roll 3 is driven via an electric motor and a speed reducer, and the upper roll 2
is rotatably supported, and is rotated by engagement with the lower roll 3 and the tiers. Since it is necessary to synchronize the rotations of the lower roll 3 and the nip pressure roll 4, the nip pressure roll 4 is rotated by appropriately selecting the gear transmission ratio. However, this does not prevent the nip pressure roll from being rotated by its own drive source.

As described above, in the single facer according to the present invention, the entire corrugated portion of the upper roll and at least the surface of the nip pressure roll are made of polyurethane, and the diameter of the lower roll is made smaller than the diameter of the upper roll and the nip pressure roll. It is also characterized by a large formation. By forming the entire stepped portion of the upper roll from polyurethane resin, the damping rate for vibration and noise increases, contributing to their reduction. Furthermore, the polyurethane resin that forms the stepped portion of the upper roll has appropriate hardness and elasticity for the paper inner cylinder compared to other synthetic chemical products such as polypropylene and vinyl chloride. It has good compatibility with the paper core, and steps can be appropriately formed on the paper core between the upper and lower corrugating rolls without heating the paper core as in the conventional method.

In addition, by making the diameter of the lower roll larger than the diameter of the upper roll and nip pressure roll,
The number of rotations of the lower roll can be reduced while maintaining the same machine speed as before. The reduction in the number of rotations suppresses the irregular oscillation of the lower roll, which directly suppresses the generation of noise and also reduces vibration, resulting in a synergistic reduction in noise.

Furthermore, since the irregular movement of the lower roll is reduced, the formation of the ridges on the center core is ensured, and tiering and high-low are prevented. Furthermore, as the rotational speed of the lower roll decreases, the centrifugal force weakens, reducing the possibility that the core will be caught in the rotational direction of the lower roll, improving separation of the stages, and even when using adhesives other than instant adhesives, irregular molding is possible. Steps and lamination defects are reduced.

Furthermore, the single facer according to the present invention can adhere to the corrugated rolls using a low-temperature adhesive without heating the corrugated rolls as in conventional devices, and therefore meets the demand for energy saving.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an embodiment of the single facer according to the present invention, and FIG. FIG. 2 is a sectional view showing one embodiment of the invention. 2...Upper roll, 3...Lower roll, 4...Nip pressure roll, 2a, 4a...Iron roll, 2b, 4b
...Vertical groove, 2c, 4c...polyurethane layer.

Claims (1)

[Claims] 1. The upper roll and metal lower roll for corrugating the continuously fed strip-shaped paper core, and the strip-shaped liner that is fed separately from the stepped paper core, are bonded with a low-temperature adhesive. In an apparatus having a nip pressure roll that applies pressure and then presses it,
At least the entire stepped portion of the upper roll is made of a polyurethane material, at least the surface of the nip pressure roll is made of a polyurethane material, and the diameter of the lower roll is larger than the diameter of the upper roll and the nip pressure roll. A single facer used in corrugated board manufacturing, characterized by a large facer.