JPS5871106A - Method of joining 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 The present invention relates to a bonding force method for veneer veneers (hereinafter referred to as veneers).

Conventionally, as a method for joining veneers, for example, the scarf joint method is generally known.

As shown in Fig. 1, this method involves making two veneers L and 2 side by side, and making a scarf cut length at the joint @ of the middle plate thickness t.
Form a bonding surface that is inclined so that it is about 10 to 12 times the
By adhesively bonding both of the bonded surfaces, a bonded veneer with uniform thickness is obtained.

However, in this method, it is extremely difficult to make the respective joint surfaces match well in the joining process, and in addition, there is a limit in terms of accuracy in processing the joint surfaces8! There was a drawback that H bonding could not be stably obtained.

The present invention provides, in place of such conventional techniques, a method for joining veneers that can achieve joining of middle boards by extremely simple means and also achieve stable and good joining. The following is an explanation based on the example.

Figures 2 (A) and (B) are explanatory diagrams showing the state of two veneers 1 to be joined, the joint ends 1a and 2a of 2, and Figures 3 (A) and (B) are Fig. 4 is an explanatory diagram showing the state of the two intermediate plates in the process of joining them together, or is an explanatory diagram showing the joined intermediate plates after they have been joined. Among the veneers for 2 seconds, the joint end 1a of the middle board 1 and the joint end n1 of the veneer 2 as necessary
Make a scarf cut on 12a. The cut length Ll is usually within the range of 2 to 12 t, preferably 3 to 6 t, where t is the thickness of the intermediate plate. Also, for I2, 0~
12t, and θTL< is approximately the same as fLl.

Of course, this type of scarf cut can be formed by any suitable means such as cutting with a knife or grinding with a sander.

Then, as shown in FIGS. 2(A) and 2(B), the joint end 1
a or 2a, or both over a suitable extent, a thermosetting adhesive such as an amino resin adhesive, a thermoplastic adhesive such as a hot melt adhesive, or a wet curing adhesive. Apply an appropriate adhesive 3 such as
Both joining ends 1a and 2a are overlapped as shown in (the adhesive 3 is not shown in this figure). Next, as shown in FIG. 3(B), a press device 7 comprising a flat base plate 4 and a press plate 6 having an elastic body 5 such as a comb plate is used to apply tf as shown in the figure. At this time, the elastic body 5 deforms the veneer 2 toward the base plate 4 while being deformed against the overlapping portion of the veneers 1 and 2. As a result, the adhesive between the joint ends of the joint screw is hardened, and the joint middle plate 8 whose base plate side surface is continuous and has a shell shape as shown in FIG.
get. As described above, the method for joining veneers according to the present invention is to make a scarf cut at the joint end of one of the 2-second intermediate boards to be joined, and cut the end of the other veneer by making l, ffi as necessary. A scarf cut is also applied to the joint end of the veneer, and both joint ends are overlapped with an adhesive interposed so that at least a part of the overlapping part is thicker than the thickness of the veneer, and the joint has a scarf cut. AfJ
Apply 11 degrees of overlapping oil and O at the pressure of 1C.
Since this is a method of joining veneers that uses an adhesive to join the joint ends, there is no strict requirement for the degree of energy applied to the scarf cut, and there is no need to adjust the degree of overlapping. A rough state is sufficient, thereby making it extremely easy to carry out the joining operation, and thereby significantly improving the stability of the joining.

Incidentally, the middle plate joined by the method of the present invention has a thickness that is at least slightly larger than the thickness of the middle plate at the joint part, but since this part accelerates the rib structure, so to speak, In addition to having one surface that is favorable in terms of strength, one side of the bonded veneer can ensure a continuous and substantially flat state, so
For example, when used as a plywood board to which a decorative board is glued, it does not pose any problem in applications where flatness is required only on the negative side of the veneer.

Further, in carrying out the present invention, FIG. 3(A) of the above embodiment
Width adjustment of the joined ends can be done directly on the base plate that applies the pressure described above or on the elastic body, or it can be done after substantially overlapping in a vacant space. Alternatively, it is also possible to move the pressure member described above toward the overlapping portion and pressurize it while performing the above operations.
) After being temporarily bonded to a state such as ), the materials may be transported to a press machine that applies the pressure described above.

Also, it is formed at the joint end of the veneer to be joined.
- Regarding the scarf cut, the cut is the fifth scarf cut.
It may have a curved cut surface like the joint ends la and 2a shown in the figure, and there is no particular restriction on the shape Sn. However, in any case, it is preferable to form a scarf cut such that the thickness of the tip 9 at the joint end becomes thinner, as shown at the joint end la in the drawings. In particular, for the joint end located on the base plate side that maintains flatness during pressurization, the thickness of the tip has a large effect on the flatness of the joined veneer 8, so the flatness requirement is The shape of the scarf cut, the cut length, etc. are determined appropriately depending on the degree of cutting, and the desired -Y surface properties are obtained. Furthermore, as shown in FIGS. 6 and 7, the joining described above can be performed on the joining end 2a attached to the elastic body side without scarf cutting the joining end 2a. As shown in FIGS. 8 and 9, the veneer 2 may be scarf cut so that the scarf cut is exposed to the outside.

In particular, in the case shown in FIG. 9, the joint end 1a located on the base plate side is also scarf cut so that the cut surface is exposed.

-Force, is the example shown in Figure 10 a joint in which the respective middle plates of the same thickness are joined in a horizontally serpentine manner?
In carrying out the present invention, it is also possible to join two-second intermediate plates with other thicknesses or fiber directions in a desired relationship.

In addition, if you place emphasis on the bonding strength of the bonded veneer, the fourth
The overlapping length 18 indicated in Figs. It is preferable to use a hot press type.Of course, other options may be used as required. L8 can be made larger or smaller than that.

However, in any case, when the joined ends are overlapped, the overlapped length 18 The basic rule is to make it larger. If you specify it! 8-11 or 18-L2.

, and further 3 or less, so that the size is about 10t or less, and in the example of Fig. 4, it is about 7
t, and in the example of FIG. 1θ, the bonding is made larger than 11 by about 5t.

Furthermore, the method of the present invention can also be used to improve the scarf cut joint method as illustrated in FIG. 1. In other words, in FIG. The overlapping length 8 (not shown) is made to be larger than the scarf cut length I by t or more by 17 to overlap the veneer thickness t or more than the condition, and the resulting thick wall of the joint is increased. The present invention described in detail above can also be put to practical use in cases where parts are unevenly distributed on one side and flatness is maintained on the other side to facilitate work.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the conventional veneer joining method, and Figure 2 (A
) ・(B) is an explanatory diagram showing the processing state of the edge of a veneer when implementing the joining force method of intermediate plates according to the present invention 7- FIG. 3(A) ・(B) is an explanatory diagram showing the joining process Figure 4 is an explanatory diagram showing a joined veneer. Figures 5 to 9 are explanatory diagrams showing an example of changing the processing state of the joint end of the veneer to be joined. Figure 1θ is an explanatory diagram showing another example of joining. 1.2 in the figure.
is a veneer, la and 2a are joint ends, 3 is an adhesive, 4 is a base plate, 5 is an elastic body, and t is a veneer thickness. Patent applicant Meinan Seisakusho Co., Ltd. Agent Patent attorney a) 1 Ken Maki - 8- 1\

Claims (1)

[Claims] 1. Make a scarf cut at the joint end of one veneer veneer, and if necessary, make a scarf cut at the joint end of the other veneer, so that at least a part of the overlapping part has a thickness of the veneer veneer. Layer both joint ends together with adhesive so that the joint ends are thicker than the original.A base plate to maintain flatness is placed on the side of the joint end with the scarf cut, and an elastic body is placed on the opposite side. A method for joining veneer veneers, characterized in that the overlapping portions are brought into contact and pressure is applied, the adhesive Ii1 is cured under the pressure, and the joining ends are joined.