JPS6023004A - Tender rising method of 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 Technical Field The present invention relates to a tenderizing method for forming a large number of small cracks in a veneer intermediate board (hereinafter referred to as a veneer).

Conventional technology Conventionally, as a veneer tenderizing method that improves veneer quality and yield by forming a large number of small cracks in the veneer, the veneer is inserted between a pair of large T rubber rollers and pressure is applied to the veneer. A method of forming a large number of small cracks using a tensile force generated by elastic deformation of a large-diameter yom roller (for example, Patent No. 7736
No. 93), a method in which a veneer is inserted between a large-diameter roller and a small-diameter iron roller, and a large number of small cracks are formed while bending the medium by the small-diameter iron roller that presses the veneer (for example, (Japanese Patent Publication No. 50-32543), between a cutting roller with a large number of cutting blades protruding from the outer periphery and a receiving roller, or between a pair of cutting rollers with a large number of cutting blades protruding from the outer periphery. A method in which a number of small cracks are formed by cutting the veneer with a 1r11 cutting blade that pressurizes the veneer (for example, Japanese Patent Publication No. 50-34
312, Japanese Patent Publication No. 49-42524), or by inserting the veneer between the carry-in roller and the carry-out roller at the first and second pressure positions separated by an appropriate distance, and applying pressure to the veneer. Generally known methods include forming a large number of small cracks using the tensile force generated by the difference in circumferential speed between the carry-in roller and the carry-out roller (Japanese Unexamined Patent Publication No. 51-110007, Utility Model Application No. 58-22490). There is. However, even in the tenderizing method described above, a large number of small cracks were uniformly formed regardless of the presence or absence of knots that repeatedly appear in the veneer. Core part 1 has fibers in the thickness direction of the veneer compared to fibers in other veneer parts, so if many small cracks are formed at the joints, the joints are likely to fall off and the quality of the veneer will deteriorate. However, there have been problems such as a decrease in the yield of intermediate plates and, for example, a decrease in work efficiency in subsequent processes such as an adhesive application process.

Purpose of the Invention The purpose of the present invention is to provide a tenterizing method for veneer veneers that can improve the quality and yield of veneers by simple means without reducing work efficiency in subsequent processes, in view of the above-mentioned conventional drawbacks. It is in.

The present invention is a tenterizing method in which a large number of small cracks are formed while pressurizing an imported veneer veneer, by reducing or releasing pressure on the veneer veneer corresponding to the joints. By effectively controlling the formation of small cracks at the joints and preventing the joints from falling off in the veneer, it improves the quality and yield of intermediate boards while preventing a decline in work efficiency in subsequent processes. .

Example Hereinafter, embodiments will be described according to the drawings.

FIG. 1 is a perspective view of a road body schematically showing a tenterizing device.

In the figure, the tenterizing device 1 has an elastic link 2 such as a comb attached to the outer periphery, a support roller 3 that is rotationally driven in the direction of the solid line arrow in the figure by an electric motor (not shown), and a support parallel to the axis of the support roller 3. A large number of pressure rollers 6 are arranged at appropriate intervals on the shaft 4, and a rubber elastic ring 5 is attached to the outer periphery. When the pressure roller 6 is brought into pressure contact with the 1JtI support roller 3 at the time (indicated by the broken line arrow in the figure), the pressing force of the pressure roller 6 against the veneer S is reduced or It is composed of a pressure member 7 such as an air cylinder that releases the pressure. In addition, S in the figure is IT
iI The middle plate has fibers in the axial direction of the support roller 3 and the support shaft 4 and is subjected to the tenderizing process. This is a joint having m fibers in the thickness direction of S.

A tenderizing method using the above apparatus will be explained with reference to FIGS. 2 and 3.

When the pressure member 7 moves back, the pressure roller 6 is pressed against the support roller 3 and is rotated by the rotationally driven support roller 3. When a veneer S having fibers is inserted between the rotating support roller 3 and the pressure roller 6 in a direction perpendicular to the conveyance direction, a large number of Small cracks Sa are formed. That is, as shown in FIG. 2, the elastic link 5 in pressure contact with the veneer S is deformed in a centrifugal direction at position A on the input side of the pressure roller 6, and the distance Q1 from the center of the pressure roller 6 is Since it is longer than the radius of the pressure roller 6, the speed v1 at the position A is slightly lower than the rotational speed (2) of the pressure roller 6. On the other hand, the valve ring 5 is at a position of 11ffiB as the center of pressure.
The maximum compression deformation occurs at , and the distance 1i111Q2 from the center of the pressure roller 6 becomes shorter than the radius of the pressure roller 6, so the speed V2 at the position B becomes slightly higher than the rotational speed V of the pressure roller 6. . Then, the veneer S is stretched in the direction orthogonal to the fibers by the tensile force generated by the speed difference (v2-Ml) between the positions A and B, thereby forming small cracks Sa.

On the other hand, when the operator visually observes that the joint H in the veneer S is conveyed to a position between the support roller 3 and the pressure roller 6, the forward movement of the pressure member 7 causes the pressure roller to move as shown in FIG. 6
move up. By this operation, the pressing force of the pressure roller 6 against the veneer S is reduced or released, and the speed difference (v2-vl:l) based on the elastic deformation of the elastic link 5 is reduced or zero, so that the small crack Sa shadow formation is substantially reduced. Thereby, as shown in FIG. 1, the tenterizing process on the veneer S including the joint H is restricted, and the removal of the joint H is prevented.

In addition to the means for moving the pressure roller 6 upward by the forward movement of the pressure member 7, in addition to the above-mentioned operator's visual inspection means, the means for moving the pressure roller 6 upward is by applying a specific wavelength to the joint H of the veneer S which is subjected to the tenderizing process in advance. It may be a means to mark with a color or tape that absorbs or reflects light, and to control the operation of the pressure member 7 based on a change in the amount of reflected light of the light irradiated onto the veneer S from the light emitting element. . By using this means, it is possible to automatically restrict the formation of a small crack Sa shadow on the veneer S including the joint H.

Further, the width of the veneer S in the direction perpendicular to the fibers, in which the formation of small cracks Sa is regulated, is appropriately set according to the state of the joint H. That is,
At the so-called living knot H, the boundary between the joint I (and the veneer part of the dragon) is relatively unclear, so a small crack Sa was formed only at the joint I as a test. , For removal, it is only necessary to set the next width that repeatedly appears depending on the state of falling, and on the other hand, at a joint H called a so-called dead joint, the boundary between the joint H and other veneer parts can be clearly identified. Therefore, the word width can be set relatively narrow from the beginning.

In addition, the joint H at which the formation of small cracks Sa is regulated is selected appropriately depending on the state of the joint H, and it is not necessary to restrict the formation of small crack Sa shadows for all joints H in practice. There is no problem.

Therefore, in the method of this embodiment, when the joint H is conveyed between the support roller 3 and the pressure roller 6, the pressing force of the pressure roller 6 against the veneer S is reduced by the forward movement of the pressure member 7. It is possible to prevent the formation of small cracks Sa in the veneer S including the joint H by releasing it, and to prevent the joint H from falling out.

Incidentally, cases in which the present invention is applied to various tenterizing methods will be explained.

First, as shown in Japanese Patent Publication No. 50-32543, a veneer is inserted between a large-diameter comb roller and a small-diameter iron roller, and a large number of small cracks are formed while bending the veneer with a small-diameter comb roller. In the tenterizing method, when the veneer portion containing the joint is conveyed between the large (d) rubber roller and the small one-piece iron roller, the large diameter j or This can be carried out by moving either one of the small diameter iron rollers upward to reduce or release the pressing force Jf against the veneer.

Next, for example, Special Publication No. 41-42524, Equity 11+'
! As shown in No. 50 34312, in the tenderizing method in which small cracks are formed by cutting the veneer using a cutting roller with many cutting blades protruding from the outer periphery, the veneer portion including the joints is When transported to the cutting roller,
To control the formation of small cracks by moving either the cutting roller or the receiving roller j=I by a pressure member to reduce or release the pressure applied to the veneer and restrict the cutting of the veneer. I can do it.

Furthermore, for example, Japanese Patent Application Laid-open No. 51-110007, Utility Application No. 58
As shown in No. 22490, the veneer S carried in is pressurized by the carrying-in III roller and the carrying-out roller at the first and second pressurizing positions separated by an appropriate distance, and the carrying-in roller and the carrying-out side In a tenterizing method in which small cracks are formed by a tensile force generated by a speed difference between the tenterizing roller and the roller, at least the carry-in roller or the carry-out roller is moved at the first pressure position or the second pressure position. By reducing or releasing the pressing force of the carry-in roller or the carry-out roller against the veneer S, the formation of small cracks in the veneer portion including the joints is restricted.

Among these, in the case where a pair of carry-in rollers and a pair of carry-out rollers are arranged at the first and second pressure positions, the carry-in roller or the carry-out roller is placed at the first or second pressure position. A method in which the pressing force on the veneer is reduced or released by moving only one of the rotations, or a method in which the carrying-in side roller and the carrying-out side roller are brought into pressure contact at the first and second pressurizing positions on the width support roller. In this case, even if the pressure applied to the veneer is reduced or released by moving either the support roller, the carry-in roller, or the carry-out roller, the formation of small cracks at the joints can be substantially prevented. Can be regulated.

DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention provides a tenderizing method in which a large number of small cracks are formed while pressurizing an imported veneer veneer, in which pressure is applied to a veneer veneer corresponding to a joint.
By reducing or releasing the pressure, the veneer quality and yield can be improved without reducing the work efficiency in the subsequent process by using a simple method that substantially restricts the formation of small cracks at the joints. This is a tenderizing method for veneer veneer.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a road body showing a portion of the tenderizing device, and FIGS. 2 and 3 are explanatory diagrams showing the state of the tenderizing process. In the figure, S indicates a veneer, Sa indicates a small crack, and H indicates a joint. Patent applicant Meinan Seisakusho Co., Ltd. Agent Patent attorney Ip Fuji Ken −

Claims (1)

[Scope of Claims] 1. In a tenderizing method in which a large number of small cracks are formed while applying pressure to a veneer veneer that has been brought in, the pressure applied to the veneer veneer corresponding to the juncture is reduced or released to reach the juncture. A method for tenderizing a veneer veneer, the method comprising substantially controlling the formation of small cracks in the veneer.