JPS63170003A - Finger bending method - 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] Industrial Application Field The present invention relates to a finger bending method for bending and forming wood, and more specifically, for forming curved parts of wooden furniture such as chair backs and table legs. This invention relates to a method for easily bending and forming wood used for.

Conventional technology and its disadvantages In response to the diversification of lifestyles in recent years, there has been a demand for diversification of wooden furniture designs.For example, designs that incorporate curved lines in parts such as the back of a chair and the legs of a table are widely adopted. has been done. In manufacturing furniture with many curved parts, it is important to improve wood processing techniques.

The most commonly used method for bending wood is the so-called hanging method, in which the wood is steamed to soften it, then fitted into a mold of a predetermined shape, and then dried and solidified to form a bend.

According to this method, the wood grain has a beautiful curve,
Moreover, there is an advantage that a product with a very good appearance can be obtained without a decrease in strength. Therefore, it is suitably used for bending raw materials such as wooden furniture. However, the bending angle that can be suitably bent using this method is three times the thickness of the wood to be bent, that is, in the case of a board thickness of 30 mm, a bending radius of 90 (R) is considered to be the practical limit due to reduced strength. ing.

Therefore, when bending with a bending radius of 90 (R) or more relative to the plate thickness is required, the method described below is used. One method is to directly cut out a piece of wood with a predetermined curve from a flat piece of wood. However, this method has the disadvantage that the effective utilization rate of a single plate is reduced and the yield is extremely poor. Moreover, a serious drawback has been pointed out that the curved portion of a cut piece of wood inevitably has a portion that extends in the direction along the grain of the wood, which tends to cause a decrease in strength at that portion.

Another method is formed plywood, in which a large number of thin veneers are laminated, bent into a predetermined shape, and then bonded together. However, this method is not suitable for creating a bend in the center of a long piece of wood, such as forming a bend in the center of a table leg, and it also requires a lot of effort and time to laminate the veneers. There are drawbacks such as the need for Moreover, despite this much effort, the finished product has the disadvantage that the wood grain is cut and the appearance is unsatisfactory.

In addition, as an application of the above-mentioned molded plywood technology, Patent No. 108
The invention "Wood Curving Method" according to No. 619 discloses a method of forming a slit in one end of a piece of wood, supplying an adhesive to the slit, and forming a bend in the end. According to this method, it is possible to easily bend the wood, but the disadvantage is that the bend can only be formed at the ends of the wood.

Purpose of the Invention The present invention has been devised in view of the above-mentioned problems and to suitably solve them. It is an object of the present invention to provide a useful means that enables the formation of curved wood with a good appearance, as well as the effective use of wood resources.

Means for Solving the Problems In order to overcome the above-mentioned problems and suitably achieve the intended purpose, the finger bending method according to the present invention provides a finger bending method in which a plurality of By drilling slits in the wood to form finger parts, applying adhesive to the finger parts, and inserting each finger part into the slit in the other piece of wood,
It is characterized in that both finger portions are interlocked with each other, and then a bending stress is applied to the joined finger portions by a bender to give a predetermined bending deformation.

Examples Next, regarding the finger bending method according to the present invention,
Preferred embodiments will be described below with reference to the accompanying drawings.

In FIG. 2, a piece of wood designated by the reference numeral 10 is finger-connected and bent as described below.
This piece of wood is particularly strong against bending from the side, and is made of square lumber or board with grain in the longitudinal direction.
For example, broad-leaved trees such as oak, beech, elm, chestnut, and ash, and coniferous trees such as cypress, pine, cedar, fir, and hiba are suitable.

A slit 12a consisting of a large number of cuts is made in one end of this piece of wood 10 in a direction parallel to the grain of the wood, and as a result, a finger portion 12 is formed at the end. Note that the depth of each cut in the large number of slits 12a is made so that it gradually becomes shallower toward the outside than on the side where the bend is applied inward. This is to prevent the tip of each finger 12 from coming into contact with the bottom of the slit 16a of the other finger to be connected and creating a gap when the joint portion is bent as will be described later. Therefore, the cutting depth of each slit 12a is determined by the curvature applied to the piece of wood 10 and the thickness of the wood.

Another piece of wood 1 to be joined at the end with this piece of wood 10
In the same manner, a slit 16a is formed in one end of wood 4 in a direction parallel to the wood grain, and as a result, a finger portion 16 is formed in the end.

These finger portions 12.16 are coated with, for example, a vinyl acetate-based or urea-based adhesive, and then, as shown in FIG. 3, both finger portions are brought into meshing contact with each other and compressed in the axial direction. One piece of wood 18 is formed.

At this time, the cutting depth of each of the many slits 12a, 16a is gradually deeper as it goes outward compared to the center side where the bending is applied, as described above, so that the bending is applied. In the state before this, one slit 12a
There is a gap of a required size between the innermost part of the finger part 16 (16a) and the tip of the finger part 16 (12) which is inserted and engaged with the innermost part of the finger part 16a.

Next, the finger-connected central portion of the wood 18 is bent at a required angle using a bender, which is a known bending machine. For example, a bottom metal 2 having the same length as the joined wood 18 and having its ends bent at right angles.
0, and use this lower metal 20 to secure both sides 1 of the wood 18.
8a and 18b are sandwiched. This prevents the joint portion 22 connecting the finger portions 12 and 16 from separating when bending is applied as described later.

Then, as shown in FIGS. 4 and 1, the wood 18 is bent by a bender consisting of a breakaway die 23 having a predetermined bending shape and a breakaway die 24 having a predetermined bending shape that forms a pair with the breakaway die 23. to hold. At this time, the separation mold 23 is located at the center of the joint portion 22, and the separation mold 24 corresponds to the wood 18 via the lower metal 20. In this state, by forcibly moving the separating mold 23 toward the separating mold 24, the wood 18 is bent at the joint portion 22. Note that as the bending at the joint portion 22 progresses, one finger portion 16 (12)
The tip of the finger comes close to the innermost part of the corresponding slit 12a (16a), and finally, the tip of the finger part and the innermost part of the slit are in complete contact with each other as shown in FIG. By holding the wood 18 in this pressed state until the adhesive dries, the series of air bending operations is completed.

The adhesive on the wood 18 is dried by natural drying,
Alternatively, any method of heating and drying using high frequency or a heat source can be used, and the adhesive used in this case is appropriate for each drying method. In this embodiment, the tips of the finger portions 12 and 16 are rectangular, but it is also possible to use a chevron-shaped finger or the like.

FIG. 5 shows another embodiment of the invention, in which the wood 18 can be bent in an S-shape. That is, the finger portions 12 and 16 are formed long, and the joint portion 2 connecting the finger portions is
2 are pressed against each other by an S-shaped open mold 23 and a corresponding S-shaped open mold 24, thereby making it possible to form an S-shaped bend. Furthermore, by performing a similar bending process, it is also possible to simultaneously form bends at two cylindrical locations in the finger portion, as shown in FIG.

FIG. 7 shows still another embodiment in which the joint portion 22 of the wood 18 is bent into two branches in a T-shape. That is, a finger portion 25a is formed at one end of a relatively thick piece of wood 25, and two thin pieces of wood 25 are processed.
Finger portions 26a and 27a are also formed at each end of 6.27, and these finger portions are bent using a bender as described above. At this time, by bending the thin wood pieces 26 and 27 in the direction of opening, a T-shaped bend is obtained.

In the above embodiments, the bending process of wood for wooden furniture was explained, but the present invention is not limited thereto, and can be applied to general interiors of wooden buildings such as handrails of stairs, and wooden products of credit unions. It can be suitably used for bending.

As described in detail, according to the finger bending method of the present invention, a curved piece of wood with a consistent wood grain can be obtained by simply bending and crimping the wood pieces forming the finger portions one time after interlocking them with each other. This method produces a finish that is no different from the normal plain wood method, and can significantly reduce processing time compared to the curved water method. Moreover, you can easily create beautiful finishes for wooden furniture of any design without using molded plywood. can be manufactured.

Currently, the aforementioned hardwoods such as oak and beech are preferred as materials for wooden furniture due to their beautiful grain and color, but these are expensive and, due to the nature of hardwoods, they require straight and long raw materials. is difficult to obtain. However, according to the present invention, since two or more short pieces of wood are joined and used, wooden furniture using the above-mentioned materials can be manufactured at low cost, and wood resources can be used effectively.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the bending state of the finger portion of the finger bending method according to the present invention, FIG. 2 is a partial front view of the wood showing the finger forming state, and FIG. 3 is a front view showing the finger portion of FIG. FIG. 4 is a front view showing a state in which the finger portion of FIG. 2 is bent, and FIG.
FIG. 6 is a front view of yet another embodiment with a trapezoidal bend, and FIG. 7 is a front view of still another embodiment with a T-shape bend. 10... Wood piece 12... Finger part 14
... Wood piece 16 ... Finger part 18 ...
·wood

Claims (1)

[Claims] [1] Finger portions (12, 16) are formed by drilling a plurality of slits (12a, 16a) in the ends of at least two or more pieces of wood (10, 14) to be joined. death,
By applying adhesive to the finger parts (12, 16) and inserting each finger part (12, 16) into the slit (16a, 12a) of the other piece of wood,
Both finger parts (12, 16) are interlocked with each other,
Then, to this joined finger part (12, 16),
A finger bending method for wood, characterized by applying bending stress with a bender to give bending deformation in a predetermined shape. [2] Finger portions (12, 16) are formed in the wood (10, 14) by drilling slits (12a, 16a) in the direction along the wood grain, and the finger portions (12, 16) and 2. The finger bending method according to claim 1, wherein the bending stress is applied in a perpendicular direction.