JP3388292B2 - Wooden tubular body - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wooden tubular body used as a pillar or beam of a building such as a temple or shrine, a decorative member, a conveying pipe for liquid or air, or a pillar for a street light or the like.

[0002]

2. Description of the Related Art For example, a pillar or a beam of a building has a diameter of 30
Although it is required to have a thickness of 0 mm or more, it has become difficult to obtain such a raw wood these days.

Therefore, conventionally, a reinforcing sheet made of cloth, paper or the like is adhered with an adhesive so as to cover the entire one surface of a veneer stripped by a rotary lace from an arbitrary raw wood, and this is stripped with a slitter to have an appropriate width. As a veneer, a wooden tubular body formed by spirally winding a plurality of band-shaped veneers around a mandrel so that the twist directions of all the band-shaped veneers are the same has been used. (See JP-A-58-91255).

[0004]

However, in the conventional tubular body, since all strip-shaped single plates have the same twisting direction, they are twisted and deformed when an axial tensile load or compressive load is applied. There was a problem. Moreover, there is a problem that the torsional strength when a torsional load is applied in the left-hand twist direction and the torsional strength when a torsion load is applied in the right-hand twist direction are significantly different.

Furthermore, since a reinforcing sheet made of cloth, paper or the like is adhered by an adhesive so as to cover the entire one surface of the strip-shaped veneer, the amount of material used increases and the adhesive is required, resulting in high material cost. There was a problem of becoming.

An object of the present invention is to provide a wooden tubular body that solves the above problems.

[0007]

A wooden tubular body according to the present invention is a tubular body formed by spirally winding and laminating a plurality of strip-shaped veneers each having a grain extending in the width direction. Therefore, the strip-shaped veneer that is wound so as to be twisted to the right and the strip-shaped veneer that is wound so that it is twisted to the left are mixed, and each band-shaped veneer is tightened while applying tightening pressure. spiral is wound, each strip veneer is formed by machine-sewing thread and comprises at least two or more parallel-like reinforcing portion extending in the longitudinal direction, form the reinforcing portion
Of the upper and lower threads that are sewn to make a sewing machine
Tension applied to one of the threads is applied to the other thread
It is made larger than the tension .

In the above-mentioned wooden tubular body, the number of strip-shaped veneers wound so as to be right-handed and the number of strip-shaped veneers wound so as to be left-handed may be the same.

Further, in the above-mentioned wooden tubular body, the strip-shaped veneers wound so as to be right-handed and the strip-shaped veneers wound so as to be left-handed are alternately present in the same number. There is. That is, the strip-shaped veneer wound so as to have a right-handed twist and the strip-shaped veneer wound so as to have a left-handed twist are alternately present one by one, or two by two. Or, there may be three or more alternately .

[0010]

[Function] A tubular body formed by winding a plurality of strip-shaped veneers each having a wood grain extending in the width direction in a spiral shape and a laminated shape, and the strip-shaped single piece wound so as to be right-handed. A board,
When the strip-shaped single plate that is wound so as to be left-handed is mixed, it is possible to suppress the occurrence of twisting deformation when receiving a tensile load or a compressive load in the axial direction. Moreover,
There is no significant difference between the torsional strength when a torsional load in the left-hand twist direction is applied and the torsional strength when a twisting load in the right-hand twist direction is applied.

When each strip-shaped veneer is provided with at least two or more reinforcing portions which are formed by sewing a thread with a sewing machine and extend in the lengthwise direction in parallel, the wooden tubular body is subjected to external force in various directions. Even when receiving the strip, breakage of the strip-shaped veneer in the longitudinal direction is prevented. Therefore, the strength of the wooden tubular body is improved. Moreover, since each strip-shaped veneer is simply provided with at least two or more reinforcing portions which are formed by sewing the thread with the sewing machine and extend in the lengthwise direction, the material used in comparison with the conventional ones. Is less.

Further, by making the tension applied to either one of the upper thread and the lower thread sewn on the sewing machine larger than the tension applied to the other thread, the effect of preventing the veneer from breaking is excellent. It will be a good thing.

Further, the number of strip-shaped veneers wound so as to be right-handed and the number of strip-shaped veneers wound so as to be left-handed are the same, or they are wound so as to be right-handed. If the same number of strip-like veneers that are turned and strip-like veneers that are wound so as to be left-handed are alternately present, twisting deformation occurs when an axial tensile load or compressive load is applied. The effect of suppressing the above is more remarkable, and the difference between the torsional strength when a torsional load in the left-handed helix direction and the torsional strength when a torsional load in the right-hand helix direction is eliminated disappears.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a wooden tubular body (1) is formed by winding a plurality of strip-shaped veneers (2) having wood grains extending in the width direction in a spiral shape and a laminated shape. , A multi-layered, for example four-layer, wood tube (3) formed from strip veneer (2)
Consists of. Adjacent wooden cylinders (3) are glued together. Appropriate adhesives can be used among the one-component type, the two-component type, the water-soluble type, the solvent type, the room temperature type, the thermosetting type and the like. The side edges of the strip-shaped single plates (2) constituting each tube (3) do not overlap but are abutted. The diameter of the tubular body (1) and the wall thickness of the peripheral wall are appropriately determined according to the purpose of use. Further, the thickness and width of each strip-shaped single plate (2) are also appropriately determined according to the purpose of use.

The strip-shaped veneer (2) forming the inner two-layer tube (3) is wound so as to have a right twist, and the strip-shaped veneer (2) forming the outer two-layer tube (3) is formed. 2) is wound so that it is twisted left. Further, it is preferable that the twist angles (A) of all the strip-shaped single plates (2) are equal. This twist angle (A) is appropriately determined according to the purpose of use of the wooden tubular body (1), but when the wooden tubular body (1) receives an axial tensile load or a compressive load during use, It is about 70 to 85 degrees, preferably about 75 degrees, and is about 20 to 30 degrees when subjected to a bending load or a radial compression load.

Each band-shaped single plate (2) is formed by sewing a thread on a sewing machine and extends in the lengthwise direction of the reinforcing section (4).
One is provided at each of the side edge portions. As the thread, thread made of polyester, rayon, cotton or the like is used, but the thread is not limited to this. Also, by making the tension applied to either one of the upper thread and the lower thread sewn by the sewing machine larger than the tension applied to the other thread, the effect of preventing the veneer from breaking is improved. Become.

In the above embodiment, the inner two-layer cylinder
The strip-shaped veneer (2) forming (3) is wound so as to have a right-hand twist, and the strip-shaped veneer (2) forming the outer two-layer tube (3) is wound so as to have a left-hand twist. However, the winding method is not limited to this, and if the tube (3) formed by two kinds of strip-shaped single plates (2) having different twist directions is mixed, the winding method is limited. is not.

FIG. 2 shows a modified example of a strip-shaped veneer forming a wooden tubular body.

In FIG. 2, the strip-shaped veneer (10) is provided with five parallel reinforcing portions (4) formed by sewing a thread and extending in the longitudinal direction.

Next, a method of manufacturing the wooden tubular body (1) will be described with reference to FIG. In the following explanation,
The right side of FIG. 3 is called front, the left side is called rear, and the upper side of FIG. 3 is left,
The lower side is called the right.

First, the rear end is fixed and the front end is 3
Two sets of horizontal mandrels (M1) (M2) supported by a supporting device (11) consisting of one roller are prepared. Then, the two strip-shaped single plates (2) are overlapped with each other in the width direction with an adhesive agent interposed between them so that the two strip-shaped single plates (2) are bonded to each other. The mandrel (M1) is spirally wound around the mandrel (M1) so as to be twisted rightward while being stably supported and supplied so as not to meander from the diagonally left rear of the mandrel (M1). At this time, one edge part of each strip-shaped veneer (2) is made to abut the other edge part. Then, while continuing to supply the two strip-shaped single plates (2), the two endless belts (12) (13) for driving rotation, which are wound around the mandrel (M1) and are wound around the mandrel (M1). By applying the tightening pressure to the mandrel (M1), the mandrel (M1) is moved forward while rotating in the direction indicated by the arrow X in FIG. 3 (a). To form an elongated cylinder (14). After the elongated cylinder (14) reaches a predetermined length, it is cut by a cutter (15) to obtain a cylindrical piece (16). The cylindrical piece (16) is pushed forward by the elongated cylinder (14) advancing from the rear, and is removed from the mandrel (M1).

Then, the cylindrical piece (16) removed from the mandrel (M1) is fitted around the other mandrel (M2). Then, the two strip-shaped veneers (2) are overlapped with each other in the width direction with an adhesive agent interposed between them so that both strip-shaped veneers (2) adhere to each other. (M2)
While being supplied while being stably supported from the right diagonally rearward direction so as not to meander, it is spirally wound around the cylindrical piece (16) so as to have a left-handed twist. At this time, one edge part of each strip-shaped veneer (2) is made to abut the other edge part. Also,
An adhesive is applied to the inner surface of the inner strip-shaped single plate (2) of the two strip-shaped single plates (2), and the adhesive is applied to the outer peripheral surface of the cylindrical piece (16). Then, while continuously supplying the two strip-shaped single plates (2), the two endless belts (17) (for rotating drive) wound around the cylindrical piece (16) are wound around the same. 18) Mandrel (M2)
While applying tightening pressure to the mandrel (M2), rotate it in the direction shown by arrow Y in Fig. 3 (b) and move it forward.
Cylindrical piece (19) consisting of four strip-shaped veneers (2) around the
To form. Then, after the cylindrical piece (19) reaches a predetermined length, it is cut by a cutter (20) to obtain a wooden tubular body (1). The wooden tubular body (1) is pushed forward by the cylindrical piece (19) advancing from the rear and is removed from the mandrel (M2). In this way, the wooden tubular body (1) is manufactured.

In the above-mentioned method for manufacturing the wooden tubular body (1), two sets of mandrels (M1) (M2) are used, but instead of this, one set of mandrels is used, and initially, Figure 3
As shown in (a), hang an endless belt to make a cylindrical piece (16), and then hang an endless belt on this mandrel as shown in Fig. 3 (b) to make a wooden tubular body (1). You may

[0025]

According to the wooden tubular body of the present invention, as described above, it is possible to suppress the occurrence of twisting deformation upon receiving a tensile load or a compressive load in the axial direction. Moreover,
There is no significant difference between the torsional strength when a torsional load in the left-hand twist direction is applied and the torsional strength when a twisting load in the right-hand twist direction is applied.

When each strip-shaped veneer is provided with at least two or more reinforcing portions which are formed by sewing the thread with the sewing machine and extend in the lengthwise direction in parallel, the wooden tubular body is subjected to external force in various directions. Even when receiving the strip, breakage of the strip-shaped veneer in the longitudinal direction is prevented. Therefore, the strength of the wooden tubular body is improved. Moreover, since each strip-shaped veneer is simply provided with at least two or more reinforcing portions which are formed by sewing the thread with the sewing machine and extend in the lengthwise direction, the material used in comparison with the conventional ones. Is less.

Further, a sewing machine sewn upper thread and lower thread
The tension applied to one of the threads to the other thread
By keeping the tension higher than the applied tension,
The disconnection prevention effect is excellent. The number of strip-shaped veneers wound so as to be right-handed and the number of strip-shaped veneers wound so as to be left-handed are the same, or they are wound so as to be right-handed. If the same number of strip-shaped veneers and strip-shaped veneers that are wound so as to be left-handed are alternately present, suppress the occurrence of twisting deformation when an axial tensile load or compressive load is applied. The effect becomes more remarkable, and the difference between the torsional strength when a torsional load in the left-handed helix direction and the torsional strength when a helix load in the right-handed helix direction is eliminated disappears.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of a wooden tubular body of the present invention.

FIG. 2 is a plan view showing a modified example of a strip-shaped single plate forming a wooden tubular body.

FIG. 3 is a plan view showing a method of manufacturing a wooden tubular body in the order of steps.

[Explanation of symbols]

(1) Wooden tubular body (2) Band-shaped veneer (4) Reinforcing section (10) Band-shaped veneer

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-55-114511 (JP, A) JP-A-47-23514 (JP, A) JP-A-58-91255 (JP, A) Actual development Sho-62- 103914 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) E04C 3/12

Claims (3)

(57) [Claims] 1. A tubular body formed by winding a plurality of strip-shaped veneers extending in the width direction in a spiral shape and a laminated shape, and having a right-handed twist. The strip-shaped veneer and the strip-shaped veneer that is wound so as to be left-handed are mixed, and each strip-shaped veneer is spirally wound while applying tightening pressure. but it includes at least two or more parallel-like reinforcing portion extending in and its length is formed by machine-sewing thread, complement
Upper thread and lower thread sewn to form a strong portion
The tension applied to one of the threads
A wooden cylinder that is made larger than the tension applied to it . 2. The wooden tubular body according to claim 1, wherein the number of strip-shaped veneers wound so as to be right-handed and the number of strip-shaped veneers wound so as to be left-handed are the same. 3. The wooden cylinder according to claim 1, wherein the same number of strip-shaped veneers wound so as to have a right-hand twist and the same number of strip-shaped veneers wound so as to have a left-hand twist are present alternately. body.