JPS58382B2 - Manufacturing method of particle board - Google Patents

Description

[Detailed Description of the Invention] This invention aims to manufacture particle board having a three-layer structure with stable quality and excellent productivity by adopting a new method for measuring the weight of forming mats. be.

Traditionally, when trying to manufacture this kind of particleboard, after forming all the layers, the weight of this formed mat is measured, and if this value is not within the preset normal weight tolerance, In addition to manually controlling the forming conveyor, the chip mat that has already been formed is returned to the raw material process, where it is again sieved into chips of different sizes for the surface layer and the inner layer, and then formed again. was.

Moreover, from the time of forming the surface layer to the time when the weight of the mat is measured, the mat has progressed to a considerable length, so returning this to the raw material process would be extremely wasteful and result in a large production loss. There was a drawback that this occurred.

In addition, if the allowable range of the mat weight is expanded in order to eliminate such loss, there is a drawback that the quality of the particle board cannot be stabilized.

The present invention aims to provide a novel particle board manufacturing method that overcomes these drawbacks.

Hereinafter, the present invention will be explained from one embodiment with reference to the drawings.

The figure is a side view of the forming process of the present invention and a block diagram showing control of the forming amount corresponding thereto.

In the figure, 1, 2, 3, and 4 are forming stations, of which 1 and 4 are forming stations for the surface layer, and 2 and 3 are forming stations for the inner layer.

First, fine surface layer chips sent from an external process enter the forming station 1, are agitated by the upper chip supply conveyor 6, and are deposited on the surface layer forming conveyor 7, and as this forming conveyor rotates, , so that it falls downward.

The same applies to other surface forming stations 4.

Similarly, coarse chips for the inner layer enter the forming stations 2 and 3, are deposited on the inner layer forming conveyor 8 from the upper chip supply conveyor 6, and then fall downward as the forming conveyor 8 rotates. It looks like this.

The fallen chips are formed on a continuous coal net 9 that is separably loaded on a chain conveyor 10 (with one particle board covered) to form a mat with a constant thickness.

In this way, a three-layer forming mat consisting of a continuous surface layer, an inner layer, and a surface layer is formed on the coal net 9, and flows in the direction of the arrow as the chain conveyor 10 rotates.

In this forming step, the amount of forming is determined by the rotational speed of the forming conveyor 7.8.

The rotational speed of this forming conveyor 7.8 is controlled by the control method described below.

That is, in the figure, reference numeral 12.13 is a weight detecting device for measuring the weight of the forming mat, and the detecting device 12 is designed to constantly measure the weight of the flowing forming mat on the surface layer.

The value detected by this detection device 12 is converted into a digital value by a converter, such as an anazolo/digital converter, as shown in the block diagram, and is displayed on an indicator. The value is compared with the weight of the surface layer mat, and if there is even a slight difference in the comparison value, it is automatically converted, for example, digital/anazoro conversion, and the speed of the surface forming conveyor 7 is changed by this signal command. let

In other words, in this case, if the weight value of the surface forming mat detected by the weight detection device 12 is larger than the set normal value, the speed of the forming conveyor 7 is reduced in proportion to it, and vice versa. If so, proportional control is performed to increase the speed of the conveyor proportionally.

In this case, the surface layer forming conveyor 7 of the forming station 4 is also proportionally controlled at the same time as shown by the chain line, so that a fixed amount of chips are always formed on the upper and lower surface layer mats.

In the figure, numeral 11 is a net weight detection device for detecting the weight of the coal net 9, and measures only the weight of the net before forming the forming mat.

The weight of the net detected here is finally memorized by magnetism, and the net passes through the weight detection device 12 of the surface mat.
When both the weight of the mat and the net are measured by this detection device 12, the memorized weight of the net is subtracted to detect the net weight of the mat.

The above-mentioned comparison with the preset normal forming mat weight of the surface layer is made by comparing with this net mat weight value.

Therefore, a very accurate comparison is made and the speed of the forming conveyor 7 is controlled proportionally.

Next, the weight detection device 13 constantly measures the weight of the forming mat of all layers on which all forming has been completed.

The weight of the mat detected here is converted in the same way as above,
Subtract the memorized weight of the coal net 9 to obtain the accurate full-layer mat weight, compare this with the preset normal full-layer mat weight, and use this as the final command. The conveyor speed (rotation speed) of the forming conveyor 8 for the inner layer is changed.

That is, similar to the proportional control of the surface layer, the forming amount of the inner layer chip is changed moment by moment by proportional control.

In this way, in this invention, the forming amount of the surface layer chip is controlled by detecting the weight of the surface layer mat, but the forming amount of the inner layer chip is controlled by detecting the weight of all layer mats. The weight of the inner layer forming mat is not detected.

In this way, the mat, which has completed forming all layers under control, is sent in the direction of the arrow, separated into individual coal nets, and heat-pressed to produce a three-layer particle board.

As described above, the present invention constantly measures the weight of the surface forming mat, proportionally controls the amount of forming of the surface layer chip based on this value, forms the surface layer chip, and measures the weight of the forming mat of all layers. This value is used to proportionally control the forming amount of the inner layer chip to form the inner layer chip, and then heat-press the forming mat consisting of the surface layer and the inner layer, so that not only all the layers , the composition ratio of the surface layer is always constant, and therefore the inner layer is also constant), so particleboard of consistently stable quality can be manufactured.

In addition, this invention constantly measures the weight of the surface layer and all mat layers, thereby proportionally controlling the forming amount of the surface layer and inner layer, respectively, so that the forming amount is constantly controlled moment by moment and is always set in advance. Since the weight of the mat is controlled to a certain level, unlike in the past, the formed mat is not returned to the raw material process, and therefore particle board can be manufactured with extremely high productivity.

[Brief explanation of the drawing]

The figures are a side view and a block diagram of the forming process of the present invention. 1 to 4: Forming station, 7: Forming conveyor for surface layer, 8: Forming conveyor for inner layer, 9
:Colenet, 11:Colenet weight detection device, 1
2: Surface layer mat weight detection device, 13: Full layer mat weight detection device.

Claims (1)

[Claims] 1 Always measure the weight of the surface forming mat,
This value proportionally controls the forming amount of the surface layer tip to form the surface layer tip, and the weight of the forming set for all layers is constantly measured, and this value proportionally controls the forming amount of the inner layer tip to form the inner layer tip. A method for producing particle board, which comprises forming chips and then hot-pressing the forming mat consisting of a surface layer and an inner layer.