JPH0624790B2 - Double phaser - Google Patents

Description

The present invention relates to a double facer, which is one unit of a corrugator, which is a facility for manufacturing corrugated board sheets.

[Conventional technology]

FIG. 3 shows a side sectional view of a double facer using dielectric heating.

In the previous step, the single-faced corrugated fiberboard sheet 1 made by a single facer (not shown) is coated with the starch paste 12 by the glue machine 13 on the top of the wavy core paper and enters the double facer 5.

On the other hand, the liner 2 is preheated by the preheater 4 and then similarly enters the double facer 5. The single-faced cardboard sheet 1 and the liner 2 that have entered the double facer are heated and bonded in the heating part 6 by dielectric heating by a grid electrode 9 to be described later to form the double-faced cardboard sheet 3. This double-sided corrugated cardboard sheet 3 is continuously cooled by the upper belt 8 in the cooling part 7.
It is carried out while being sandwiched between the lower belt 10 and the lower belt 10 and sent to the next step.

At this time, as a typical layout of the dielectric heating device,
As shown in FIG. 3, there is one in which several units are installed on the lower surface side of the corrugated board sheet 3 in parallel with the width direction of the corrugated board sheet 3 so that the (+) poles and the (−) poles alternate. . Various arrangements of the electrodes on the corrugated cardboard sheet 3 can be considered as shown in FIGS.

Here, when a high frequency voltage is applied between the (+) pole supported by an insulator (not shown) and the (−) pole grounded,
An electric field 15 shown by an arrow in FIG. 7 is generated. Due to the dielectric heating due to this electric field, E ² εt is contained in the corrugated board sheet 3.
Heat is generated in proportion to anδ (E: electric field strength, tanδ: dielectric loss coefficient ,: frequency, ε: relative permittivity).
The value of nδ is 20 to 30 times as high as the water content in the paste and the water content in the corrugated board sheet 3, so that the generated electric field concentrates on the adhesive bonding portion 14, and extremely efficient heating and drying are performed. Done.

By the way, in a double facer using such a dielectric heating method, as an oscillator specification usually considered when applying the dielectric heating method, a constant input method is used, or an input corresponding to the operating speed fluctuation in the double facer is applied. It is one of the input control methods for controlling. But,
Since there are various types of corrugated board manufactured by the corrugator, there is a possibility that the quality of the corrugated board cannot be homogenized due to variations in the drying conditions of the corrugated board only by the above control method.

[Problems to be solved by the invention]

As described above, in the double facer to which the dielectric heating method is applied, no particular consideration has been given to the input control of the dielectric heating at present, and there are multiple load fluctuation factors that influence the dielectric heating amount. Regardless of these, the simple control method is adopted by ignoring them. Therefore, it is difficult to say that proper drying is performed for each of the different specifications of the corrugated board that is manufactured, and this may affect the quality.

The present invention, as a result of diligent research based on these points, elucidates the factors contributing to load fluctuations of the adhesive adhered to the corrugated cardboard sheet that is the object to be heated, and comprehensively while checking the fluctuations between these factors. It is an object of the present invention to provide a double facer in which the output of the oscillator is adjusted to obtain an appropriate amount of dielectric heating.

[Means for solving problems]

Therefore, the present invention is a double facer for producing a double-faced corrugated sheet by attaching a liner to the corrugated core paper of a single-faced corrugated sheet, in which a dielectric heating device is disposed in proximity to the attaching surface, and at least the traveling speed of the single-faced cardboard sheet. And a means for detecting the amount of glue attached to the top of the corrugated core paper of the same sheet, and the load fluctuation is detected by the traveling speed and the amount of glue detecting means. It is equipped with an arithmetic unit that performs arithmetic processing and an oscillator to which the result is sent. The oscillator adjusts the necessary output and performs heating under optimal conditions. Is the means of.

[Action]

According to the present invention, the corrugated board manufacturing conditions, that is, the operating speed,
Even if each condition such as the corrugated cardboard sheet and the paste condition changes, the output control of the oscillator is immediately executed correspondingly, and as a result, the paste that is the object to be heated is appropriately dielectrically heated. Drying can be realized.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a conceptual diagram of output control for carrying out the present invention, and also shows a side sectional view of a double facer in which the grid electrode 9 is arranged on one side of a corrugated board sheet.

In the present embodiment, the operating speed, the width of the corrugated cardboard sheet, and the amount of paste are targeted as the factors of the load fluctuation of the object to be heated. Other factors include the corrugated board sheet pitch, the glue concentration, and the like, but in the present invention, at least the operating speed and the glue amount are to be inspected among these factors.

In FIG. 1, 1 is a single-faced cardboard, 2 is a liner, and 3 is a double-faced cardboard sheet having a liner attached to the top of the corrugated core paper of the single-faced cardboard 1.

4 is a preheater for preheating the liner 2, 5 is a double facer, 6 is a heating part for heating the corrugated cardboard sheet in the first half of the double facer 5, 7 is a cooling part which is a cooling zone following the heating part 6, and 8 is a double facer. An upper belt which is arranged over the entire area of the single-sided corrugated board and runs in the traveling direction of the corrugated board, in contact with the liner surface on the side of the single-sided corrugated board, 9 is a grid electrode, 10 is a lower belt extending between cooling parts 7, and 11 is an upper belt. 8 is a drive roller, 12 is a starch paste, and 13 is a glue machine. The above is essentially the same as the conventional part shown in FIG.

In this embodiment, an operating speed detection sensor 17 and a cardboard sheet width detection sensor 18 are arranged facing the single-sided corrugated board 1, and a corrugated core paper is formed at a portion of the single-sided corrugated board 1 that has passed through the glue machine 13. A glue amount detection sensor 19 is arranged so as to face. Each of these detection sensors 1
All detection signals from 7, 18, and 19 are sent to the arithmetic unit 20. The arithmetic unit 20 receives these signals, performs arithmetic processing, and sends the result to the oscillator 16.

Here, the signal of the driving speed detection sensor 17 may be replaced by a motor voltage or a rotation speed signal. Further, as the corrugated cardboard sheet width detection sensor 18, an edge sensor which is an optical known method is used, and an output signal from a computer input to a centralized production control system can be used instead.

In the above configuration, when the load of the object to be heated fluctuates, the fluctuation of the load is detected by the above-mentioned detection sensors or their substitute signals, and the oscillator 16 adjusts the necessary output under the optimum conditions. The heating is done. As a method of adjusting the output, the relationship of the required output with respect to the load of the object to be heated is programmed in advance in the oscillator 16, the signals from the respective sensors are arithmetically processed by the arithmetic unit 20, and the result is set as the above. A system for automatically controlling the output compared with the value may be adopted.

A method of setting the oscillator output E · I will be exemplified below. Since the load of the object to be heated is proportional to the width B of the corrugated board sheet, the amount q of the adhesive adhering to the corrugated corrugated crest 1 streaks of the corrugated sheet, and the corrugated pitch P, the oscillator outputs E / I must be increased or decreased accordingly. Since the required heating amount is proportional to V / L (operating speed V, heating length L), the load constant C of the object to be heated is defined as follows, and the oscillator output E · I is adjusted in proportion to C. .

The relationship is shown graphically in FIG.

〔The invention's effect〕

As described above in detail, according to the present invention, the cause of the load fluctuation of the object to be heated is clarified, and the output of the oscillator is program-controlled based on this factor. It became possible to adjust the output of various oscillators. As a result, as a matter of course, the drying of the corrugated cardboard sheet during normal manufacturing is made uniform, and even when the specifications of the corrugated cardboard sheet are changed, appropriate drying can be performed immediately and appropriately. Therefore, the quality of the corrugated board sheet is made uniform and the quality is improved.

[Brief description of drawings]

FIG. 1 is a schematic side sectional view of a double facer showing an embodiment of the present invention, and FIG. 2 is a diagram showing an example of a correlation between an oscillator output applied to output adjustment in an oscillator of the present invention and a load to be heated. FIG. 3 is a side sectional view showing a conventional double facer to which a dielectric heating method is applied, FIGS. 4 to 6 are views showing examples of arrangement of grid electrodes on a corrugated cardboard sheet, and FIG. 7 is a view showing an electric field generation state. It is an AA sectional view of a figure. Description of main parts of the figure 16 …… Oscillator 17 …… (Operating speed) detection sensor 18 …… (Cardboard sheet width) detection sensor 19 …… (Adhesive amount) detection sensor 20 …… Calculator

Claims (1)

[Claims] 1. A double facer for producing a double-sided corrugated sheet by attaching a liner to a corrugated core paper of a single-sided corrugated sheet, and a dielectric heating device is disposed in the vicinity of the attaching surface, and at least the traveling speed of the single-sided corrugated sheet is improved. The load fluctuation is detected by the detecting means and the means for detecting the amount of glue attached to the top of the corrugated core paper of the same sheet, and the load speed is detected by the means for detecting the traveling speed and the glue amount, and calculation is performed in response to this detection signal. A double facer comprising a processing unit for processing and an oscillator to which the result is sent, the oscillator adjusting necessary output and performing heating under optimum conditions.