JPH0450897B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a single facer for manufacturing single-sided corrugated cardboard, which is a unit constituting a corrugator.

(Prior art) As shown in FIG. 3, in the conventional single facer, a core paper 8 is supplied to the upper roll 1 side, and is bitten into the meshing part of the upper roll 1 and the lower roll 2, and is formed into a wave shape. The core paper 8' is then transferred as the lower roll 2 rotates, the glue 7 in the glue container 6 is scooped up by the glue roll 4, and the doctor roll 5 adjusts the glue film. After that, the glue roll 4 applies glue to the corrugated portion of the core paper 8'. On the other hand, the liner 9 supplied to the pressure roll 3 side and the glued core paper 8' are adhered to each other at the pressing portions of the lower roll 2 and pressure roll 3 to form a single-sided corrugated paperboard 10. In the conventional single facer shown above, generally the upper roll 1 is connected to the lower roll 2,
In addition, the pressure roll 3 applies a linear pressure to the lower roll 2, respectively.
It is pressed at 20 to 60 kg/cm. The former is a pressurizing force for performing corrugation on the core paper 8, and the latter is a pressurizing force for providing adhesive force between the core paper 8' and the liner 9. In addition, the lower roll 2, together with the upper roll 1, has tooth-shaped steps processed on the outer surface of the roll.
On the other hand, since the pressure roll 3 has a smooth surface, the corrugations of the lower roll hit the surface of the pressure roll 3 through the core paper 8' and the liner 9 at high cycles during operation. In this structure, there are an upper roll 1, a lower roll 2 and a pressure roll 3.
is mainly due to the excitation force based on [excitation change between lower roll 2 and pressure roll 3] × [contact spring constant between lower roll 2 and pressure roll 3] It vibrates with a tooth number cycle NZ (corrugated roll rotation speed N x tooth number Z), and when the tooth number cycle NZ matches the natural frequency of the roll system, it resonates, and the three rolls in particular vibrate violently. During such resonance, the pressure roll 3 and the lower roll 2 collide violently, and a large collision load is applied to the core paper 8' and liner 9 sandwiched between the rolls, causing the sheet to break or break. , depending on the phase state of vibration,
A phenomenon occurs in which the core paper 8' and the liner 9 are not bonded together, and moreover, a large amount of noise is generated.

The above-mentioned problems are becoming more problematic as machines become faster and sheet quality tends to deteriorate. For this reason, a single facer has been proposed that reduces vibrations generated in rolls and the like and reduces noise. One example is the structure shown in FIG. The pressure roll 3' has a cylindrical core 14 formed around the axis C, and the outer periphery of the cylindrical core 14 has a relatively thin wall (5 mm to 20
A cylindrical sleeve 13 with a diameter of about mm) is fitted, and there is a gap between the cylindrical core 14 and the cylindrical sleeve 13.
(approximately 2 mm to 10 mm) is formed. In between, a low melting point alloy 15 such as solder is sealed. As described above, the cylindrical sleeve 13 is made relatively thin, and a low melting point alloy is sealed in the inner part, thereby reducing the impact force and damping the vibrations of the sleeve 13. Low melting point alloy 1 sealed between the cylindrical core 14 and the cylindrical sleeve 13
5 also plays the role of ensuring heat conductivity. In other words, steam is introduced into the cylindrical core 14 to maintain the temperature of the surface of the cylindrical sleeve 13 at 160 to 220°C,
A cylindrical core 14 is used to rapidly gel the liquid starch paste for bonding the liner 9 and the core 8'.
It serves to improve heat transfer between the sleeve 13 and the cylindrical sleeve 13.

However, in this pressure roll, steam is introduced into the center of the cylindrical core 14 as a heating source, so
The thickness of the core 14 needs to be thin in terms of heat conduction efficiency to the surface of the cylindrical sleeve 13.
The natural frequency of the lower roll 2 decreases, and the tooth number cycle of the lower roll 2 decreases within the operating speed range of the single facer.
There is a new problem in that it resonates with the excitation force from the NZ and generates loud noise.

(Means for Solving Problems) The present invention was proposed to solve the above-mentioned conventional drawbacks, and is a single facer equipped with an upper roll, a lower roll, a pressure roll, and a pasting roll. Consisting of a thick-walled cylindrical core and a cylindrical sleeve inserted into the core at a distance, a steam introduction pipe is provided between the core and the sleeve, and the remaining space is filled with a low melting point metal. A steam introduction pipe as a heating source is installed between the core and the sleeve to increase heat transfer efficiency, increase the core wall thickness, raise its natural frequency, and increase the speed within the operating speed range. The object of the present invention is to provide a single phasor that can be prevented from resonating with the frequency of the excitation force, and can also reduce noise by attenuating impact force and elastic vibration using a thin sleeve and a low melting point alloy.

(Example) The present invention will be explained by referring to the most preferred illustrated embodiment shown in FIGS. 1 and 2. In the figure, 20 is a pressure roll, and the other structure is the same as the conventional one. The pressure roll 20 includes a thick cylindrical core 21 and a thin cylindrical sleeve 22 attached to the outer periphery of the core 21 at intervals. A number of steam introduction pipes 23 are provided between the core 21 and the sleeve 22, and the introduction pipes 23 are connected to a steam source (not shown) via the shaft end of the pressure roll 20. Furthermore, the interspace is filled with, for example, a low melting point metal 24 such as solder.

This embodiment is constructed as described above, and the core paper 8 is supplied to the upper roll 1 side, and is formed into a corrugated core paper 8' by the upper roll 1 and the lower roll 2, and then by the gluing roll 4. At the same time, it is glued to the nape and bonded to the Naina 9 sent to the pressure roll 20 side to form the single-sided corrugated board 10. At this time, the thin sleeve 22 alleviates the impact force caused by the collision of the flutes of the lower roll 2, and furthermore, the low melting point metal 24 damps the elastic vibrations of the sleeve 22. In addition, since the sleeve 22 is heated by the steam introduced into the steam introduction pipe 23 via the low-melting point metal 24, the sleeve 22 can be heated efficiently without considering the thermal resistance of the core 21 as in the past. can maintain a constant temperature. Therefore, the wall thickness of the core 21 can be made larger than the conventional thickness of about 40 mm, and as a result, the natural frequency becomes large, so that the frequency of the excitation force does not coincide with the operating speed range.

(Effects of the Invention) According to the present invention, as described above, the thin-walled sleeve alleviates the impact force caused by the collision of the tiers of the lower roll,
In addition, the elastic vibration is damped using a low melting point metal, and the thickness of the core is increased to increase its natural frequency to avoid resonance of the excitation force with the frequency NZ within the operating speed range of the single facer. As a result, it is possible to effectively prevent not only large noise caused by resonance but also noise in general.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention,
Fig. 1 is a partially cutaway front view of the pressure roll, Fig. 2 is a cross-sectional view of the pressure roll, Fig. 3 is a side sectional view of a conventional single facer, and Fig. 4 is the same as Fig. 3. A partial front view showing a part broken away, FIG. 5 is a partial side sectional view of another conventional single phaser,
FIG. 6 is a partially cutaway front view of FIG. 5. 1...Upper roll, 2...Lower roll, 4...
Gluing roll, 20...pressure roll, 21...cylindrical core, 22...cylindrical sleeve, 23...steam introduction pipe, 24...low melting point metal.

Claims (1)

[Claims] 1. In a single facer equipped with an upper roll, a lower roll, a pressure roll and a pasting roll,
The pressure roll is composed of a thick-walled cylindrical core and a cylindrical sleeve inserted into the core at a distance,
A single facer characterized in that a steam introduction pipe is provided between the core and the sleeve, and the other space is filled with a low melting point metal.