JPS61181603A - Tenderizing method and device for veneer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION ((a) Industrial Application Field The present invention is directed to veneer lace, veneer slicer, and other veneer cutting machines used in the field of plywood manufacturing.
Alternatively, a veneer veneer tenderizing method for softening the material of a veneer veneer with upward curls and burrs, which has been dried by a veneer dryer such as a veneer dryer, and correcting the curls and burrs. It is related to the device.

(0) Prior Art Conventional methods and apparatuses for tenderizing veneer veneers of this type include, for example, Japanese Patent Application Laid-Open No. 48-87003, a method for tenderizing veneer veneers. A veneer veneer tender using the so-called knife method, in which a number of blades are protruded in the axial direction of one or both of the surfaces of a pair of cylinders to form numerous cuts in the veneer veneer material fed between the rotating cylinders. As disclosed in ``Rising Method and Apparatus'', JP-A-51-11 ooo7 @ Method and Apparatus for Forming Small Cracks in Veneer Plywood, JP-A-59-91004, Apparatus for Tender Rising of Veneer Plywood, etc. [4] Consisting of a pair of upper and lower loading rollers and unloading rollers arranged at different positions in the front and rear.
Today - Regarding the veneer conveyance mechanism with the R-configuration, by making the speed of the lower carry-out roller faster than the speed of the upper carry-in roller, a large number of splits are formed in the material of the veneer veneer held between both rollers. There are conventional techniques such as the so-called veneer veneer tenderizing method and apparatus using a differential loading/unloading speed method.

(C) Problems to be Solved by the Invention This type of veneer veneer tenderizing method and apparatus, which is the prior art described above, involves making numerous cuts from above and below into the material of the veneer veneer using a knife. material,
In particular, the so-called knife method is used to correct curls and cracks by cutting off the continuity of the fibers 7q, or by pulling the veneer veneer using the speed difference between loading and unloading to create a large number of splits in the material. By refusing to use continuous materials, especially fibers, to correct curls and blemishes.
Since it was based on the so-called loading/unloading speed differential method, the former was designed to prevent small pieces of broken veneer veneer from surrounding the cutting edge and wood chips, etc. There are many cases of so-called blade clogging, where the blade gets stuck tightly between the edges and significantly impairs the cutting action of the blade in that area. Since the warisaki was only forcibly pulled to form warisaki at random, the distribution and size of the warisaki were uneven, and therefore, the former was not effective due to the unexpectedly caused blade clogging phenomenon. There is a serious drawback that has made the function of correcting curls and blemishes unstable, and the latter not only causes severe damage to the material due to excessive softening of the weak parts, but also increases the risk of splitting as the thickness increases. It had dwarf disadvantages such as loss of formative functions.

■Means for solving the problem In order to eliminate the drawbacks of the above-mentioned prior art, the present invention does not use the method of directly forming a cut using a knife or the method of forming a split using a difference in loading and unloading speeds, as in the prior art. The wood structure of the veneer veneer is shredded into broken lines by means of intermittent laser beam irradiation from an indirect space, and the curls and cracks caused by the continuity of the material, especially the fibers, are corrected all at once. The main components thereof include a) a laser beam irradiator, b) a laser beam scanner, and C) a laser power supply circuit and an intermittent control circuit.

(The laser beam emitted from the laser beam irradiator of the present invention in a substantially horizontal direction is turned into a pulsed waveform laser beam by an intermittent control circuit inserted into the power supply circuit of the irradiator, and is turned into a laser beam with a pulse waveform. The sheet is sent to a rotating scanner that repeatedly irradiates the sheet surface in a direction orthogonal to the direction of conveyance.

The laser beam sent to the scanner is corrected by a correction lens, etc., and its optical path is changed in a substantially vertical direction, and the laser beam is intermittently irradiated back and forth from directly above the surface of the veneer veneer. The thermal energy of a laser beam irradiates the wood structure in a broken line shape to shred it into thin cuts. In this case, if the irradiated surface of the veneer veneer is a surface with no back cracks formed during cutting, and if the back surface has many back cracks formed during cutting, the laser beam may penetrate through the material. Even if the output is adjusted so that the shredding stops in the middle of the process, it is possible to correct curls and blemishes as desired.

In addition, in the intermittent irradiation of the laser beam of the present invention, the pulse waveform of the intermittent irradiation is changed depending on the degree of curling and fraying of the veneer veneer, or the pulse waveform is temporarily stopped. Either irradiate intermittently with a pulse waveform that can form many fragmented areas, and on the other hand, irradiate relatively flat areas intermittently with a pulse waveform that can form coarse fragments, or temporarily stop the irradiation to avoid wasting energy. It is also possible to prevent the consumption of

Furthermore, the intermittent irradiation of the laser beam of the present invention is used to reduce the overlap phenomenon caused by the application of adhesive in the plywood bonding process. forming part
It is also possible to temporarily stop the irradiation of the laser beam near the butt surface by controlling the irradiation width using light receiving elements installed near both sides of the veneer veneer. It is something.

(g) Example As shown in FIGS. 1 and 2, a veneer veneer 1 is conveyed by conveyors 2a and 2b in a direction orthogonal to the fiber direction, and is conveyed at right angles to the direction of conveyance. An irradiator 4 such as a carbon dioxide laser that emits a laser beam 3 from a substantially horizontal direction is installed on the conveyors 2a and 2b so that the laser beam 3 can be irradiated intermittently and repeatedly back and forth from directly above the conveyor. A laser beam 3 emitted from the veneer in a substantially horizontal direction is changed to a substantially vertical direction by a rotating scanner 5 such as a polyhedral mirror, and the laser beam 3 is intermittently reciprocated from directly above the surface of the veneer veneer 1 during the transportation process. The wood structure is exposed to the irradiation thermal energy of the laser beam 3.
This device is designed to gradually form a large number of thin cuts 6 in the shape of broken lines in a direction perpendicular to the conveying direction. Further, the intermittent irradiation of the laser beam 3 is performed by controlling the laser power supply circuit 7 that supplies power to the irradiator 4 to be turned on and off by an intermittent control circuit 8. Usually, the intermittent control circuit 8 includes a pulse transmitter, A variable pulse transmitter such as a timer is built-in, so operate this variable pulse transmitter to generate a pulse signal with an arbitrary waveform that matches the material and shape of the veneer veneer 1, thereby generating the laser beam 3. This device is capable of forming cuts 6 of any number and length with any desired width on the surface of a veneer veneer by intermittent rusting.

Note that 9 in the figure is a motor that drives the rotary scanner 5 such as a polyhedral mirror.

(g) Effects of the Invention As mentioned above, the present invention does not involve the prior art of this type, which involves direct cut-forming means using a cutter or crack-forming means based on the difference in loading and unloading speeds, but indirectly generates a laser beam from space. The structure is such that the wood structure of the veneer veneer is shredded into broken lines by means of intermittent irradiation with a beam, and the curly cracks caused by the continuity of the material, especially the fibers, are corrected all at once. Small pieces of veneer veneer that broke around the time when the knife was cutting into the material that was being used, or wood chips that got on the veneer veneer during the transportation process, got stuck tightly between the edges of the blade, causing the cutter to break in that area. Due to the frequent occurrence of the so-called blade clogging phenomenon, which significantly impairs the cutting action of
There are serious drawbacks that have made the actual curl and blemish correction function unstable, and veneer veneers that have fragile parts due to the material of the loading/unloading speed difference method are forcibly removed by the front and rear speed difference. The present invention has been able to eliminate all of the serious problems caused by randomly forming splits by stretching, such as severe damage to the material and loss of the splits forming function due to increase in thickness. The tenderizing method and device using intermittent irradiation with a laser beam from a space does not directly contact the surface of the veneer veneer with objects such as cutlery, and can be used to create any number and length of broken lines that match the material and shape of the veneer. Cuts that shred the wood structure in a shape can be formed on the board surface with any width, so the stability of the cut formation and the accompanying straightening function is extremely excellent across all board thicknesses, improving process efficiency and improving veneer This invention greatly contributes to improving yields.

[Brief explanation of the drawing]

The drawings show an example of the implementation of the present invention, in which FIG. 1 is a side view, FIG. 2 is a plan view, and FIG. 3 is a front view. 1...Plywood veneer, 2a, 2b...Conveyor, 3.
... Laser beam, 4... Irradiator, 5... Scanner, 8... Laser power supply circuit, 9... Intermittent control circuit.

Claims (2)

[Claims] (1) While transporting the veneer veneer, a laser beam is intermittently and repeatedly irradiated in the direction orthogonal to the transport direction, and the irradiation thermal energy of the laser beam shreds the wood structure of the veneer veneer in the shape of broken lines during the transport process. A method for tenderizing veneer veneer, which is characterized by: (2) A conveyor that conveys the veneer veneer, a laser beam irradiator installed on the conveyor, and a laser beam emitted from the irradiator perpendicular to the conveying direction to convey the veneer veneer. A veneer veneer single sheet tenderizing device comprising: a laser beam scanner consisting of a polyhedral mirror or the like that reciprocates irradiation onto a surface; and an intermittent control circuit that intermittently controls a laser power supply circuit that supplies power to the irradiator. .