JPH0655463B2 - Double phaser - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a double facer for a paperwork machine product, and more specifically, an electrode is arranged near a strip-shaped corrugated cardboard sheet and a high frequency voltage is applied to the electrode. The present invention relates to a double facer that employs a so-called dielectric heating method for heating the sheet.

(Prior Art) The above heating method is different in principle from the conventional heat conduction heating by a hot plate, and therefore, as a conventional technology, the one that has been put to practical use by adopting the dielectric heating method for the double facer is: Currently none.

(Problems to be Solved by the Invention) In the double facer adopting the dielectric heating method, the output of the oscillator is usually designed according to the maximum operating speed and the maximum sheet width of the double facer which regulates the load of the material to be heated.

The characteristic of dielectric heating is that the power loss is E ² εtanδ
(F: frequency, E: electric field strength, ε: relative permittivity of object to be heated, tan δ: dielectric loss coefficient of object to be heated). Here, ε and tanδ are values peculiar to the object to be heated, and according to the inventor, the value of the product ε · tanδ is such that the glue is selectively concentrated on the glue in the order of tens of thousands with respect to 1 of the paper, and the paste is heated. It turns out. Therefore, if there is no restriction on the output control method, there is a concern that the maximum output of the oscillator will be supplied to the sheet as soon as the corrugated board sheet enters the double facer regardless of the operating speed and the paper width. The inventors have found that a discharge phenomenon or the like occurs in the case of overload.

The present invention is intended to solve such a problem and always perform stable output supply with respect to changes in the load of the object to be heated.

(Means for Solving Problems) Therefore, according to the present invention, an electrode is arranged in the vicinity of a strip-shaped corrugated cardboard sheet which is glued on the step top and continuously running, and a high frequency voltage is applied to the electrode to apply the sheet. In the double facer that heats, the operating speed is detected, the signal is fed back to the electric output system, and electric power proportional to [preset maximum sheet width] x [operating speed] is applied,
The voltage between the electrodes is adjusted by adjusting the capacity of a variable capacitor connected in series to the electrodes in response to the difference in the paper width at a predetermined speed, and this is a means for solving the above problems.

(Operation) As an output control method for the object to be heated, the operating speed is detected, the signal is fed back to the electric output system, and electric power proportional to [predetermined maximum sheet width] x [operating speed] is applied, On the other hand, with respect to the load fluctuation due to the difference in the paper width, the capacitance is changed according to the paper width by the variable capacitor connected in series to the grid electrode, and the voltage between the grid electrodes is adjusted.

As described above, the output control without excess or deficiency is performed with respect to the load of the object to be heated.

(Example) Hereinafter, the Example of this invention is described according to drawing.

FIG. 1 shows a conceptual diagram of a control device which is an embodiment of the present invention. Here, 1 is a corrugated cardboard sheet, 2 is a grid electrode as a dielectric heating device, 3 is a high frequency oscillator, 4 is an operation speed detection sensor, 5 is a paper width detection sensor, and 6 is a high frequency voltage. 7
Is an arithmetic circuit previously calculated and incorporated in the high-frequency oscillator 3, and is an example of a diagram of electric power applied in proportion to [predetermined maximum sheet width] × [operating speed].

Further, 8 is a typical example of an oscillator circuit also incorporated in the high frequency oscillator 3, 9 is an equivalent capacitor between electrodes, 10 is a coil, and 11 is a variable capacitor. Here, in the high frequency oscillator 3, for example, a predetermined output is supplied to the load by the arithmetic circuit 7 based on the speed detected by the operating speed detection sensor 4. Therefore, if the operating speed is determined, the maximum value of the output according to the speed is set. Next, with respect to the difference in the paper width at the same speed, for example, the signal from the paper width detection sensor 5 is fed back to change the capacitance of the variable capacitor 11 to adjust the inter-electrode voltage.

That is, the voltage between electrodes in the oscillation circuit 8 is V ₁ = V · C
₂ / (C ₁ + C ₂ ), and when the paper width is wide and the load is large, the capacitance C ₂ is increased by the signal of the paper width detection sensor, and in the opposite case, C ₂ is made small so that stable output is always performed. Is. (However, C ₁ : equivalent capacitor capacity between grid electrodes, C ₂ : variable capacitor capacity, V ₁ : voltage between grid electrodes, V: voltage across coil) (Effect of the invention) As described above in detail, the present invention According to the above, it is possible to perform stable output control without excess or deficiency against differences in operating speed and paper width, and prevent problems such as electric discharge.
It can be expected to improve product quality.

[Brief description of drawings]

 The figure is a conceptual diagram of output control showing an embodiment of the present invention. Description of main parts of the figure, 3 ... High frequency oscillator 4 ... Operating speed detection sensor 5 ... Paper width detection sensor 7 ... Arithmetic circuit 8 ... Oscillation circuit 11 ... Variable capacitor

Claims (1)

[Claims] 1. A double facer, in which an electrode is arranged near a strip-shaped corrugated cardboard sheet which is glued to the top of a step and which runs continuously, and a high frequency voltage is applied to the electrode to heat the sheet, the operating speed is detected. The signal is fed back to the electric output system, and [preset maximum sheet width] x
A double facer characterized by applying a power proportional to [operating speed] and adjusting the capacity of a variable capacitor connected in series to the electrodes to adjust the voltage between the electrodes against the difference in paper width at a predetermined speed. .