JP3353202B2 - Method of manufacturing wooden tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a wooden cylinder used as a pillar of a building such as a temple or the like, a decorative member, a pipe for transporting liquid or gas, or a column of a streetlight.

[0002]

2. Description of the Related Art For example, pillars and beams of a building are required to have a diameter of 300 mm or more, but it has recently become difficult to obtain such logs.

[0003] Conventionally, as a pillar or beam of a building, instead of a log having a diameter of 300 mm or more, a cloth having an arbitrary diameter smaller than this is covered by a rotary lace so as to cover an entire surface of a single veneer. A reinforcing sheet made of paper or the like is adhered with an adhesive, and this is made into a strip-shaped veneer having an appropriate width by a slitter. In this manner, a wooden tube formed by being spirally wound has been used (see Japanese Patent Application Laid-Open No. 58-91255).

[0004] However. In the above-described conventional wooden cylinder, since the twisting directions of all the strip-shaped veneers are the same,
There has been a problem that torsional deformation occurs when an axial tensile load or a compressive load is applied. In addition, there is a problem that the torsional strength under a torsional load in the left-handed torsional direction is greatly different from the torsional strength under a torsional load in the right-handed torsional direction. Further, since a reinforcing sheet made of cloth, paper, or the like is adhered with an adhesive so as to cover one entire surface of the belt-shaped veneer, the amount of material used increases and the adhesive is required, resulting in a high material cost. was there.

[0005] In order to solve such a problem, the present applicant has first formed a plurality of strip-shaped single plates, each of which has a grain extending in the width direction, by spirally winding the strips in a stacked manner. Proposed a wooden tube in which a strip-shaped veneer wound right-twisted and a band-shaped veneer wound left-twisted are mixed (see JP-A-8-105155). .

[0006] Such a wooden tube is disclosed in Japanese Patent Application Laid-Open No. 8-1051.
As described in JP-A-55-55, it is manufactured by the following method. That is, first, the two band-shaped veneers are overlapped with a slight displacement in the width direction with an adhesive interposed therebetween so that the two band-shaped veneers adhere to each other, and this is spirally wound around the mandrel. Wound so that it twists right. At this time, one side edge of each band-shaped veneer is brought into contact with the other side edge. Next, the other two band-shaped veneers were overlapped with each other slightly shifted in the width direction with an adhesive interposed therebetween so that the two band-shaped veneers adhered to each other, and this was wound first. It is spirally wound around the band-shaped veneer so as to be left-handed, thereby forming a cylindrical body composed of four layers of band-shaped veneer around the mandrel. At this time, one side edge of each band-shaped veneer is brought into contact with the other side edge. Thereafter, the tubular body is removed from the mandrel and the adhesive is dried at room temperature, or the adhesive is cured by heating. Thus, a wooden cylinder is manufactured.

However, in the above-described method for manufacturing a wooden tube, the winding pressure of the band-shaped veneer is loosened until the adjacent band-shaped veneer is bonded to the inside and outside after the tubular body is removed from the mandrel. However, there is a problem that a gap is generated between adjacent strip-shaped veneers, resulting in an adhesion defect.

An object of the present invention is to solve the above-mentioned problems and to provide a method for manufacturing a wooden cylinder in which no adhesive defect occurs between adjacent strips inside and outside.

[0009]

SUMMARY OF THE INVENTION A method of manufacturing a wooden cylinder according to the present invention comprises a plurality of wooden strips which are sequentially spirally wound around a mandrel and twisted right and left. A method of manufacturing a wooden tube including forming a cylindrical body composed of a plurality of layers of band-shaped veneers by winding them in a laminated shape so as to be mixed, and interposing an adhesive between adjacent band-shaped veneers inside and outside. In, the innermost strip veneer
Before winding around the mandrel,
Release layer with thermal expansion property by covering metal tube
Is formed, and a cylindrical body is formed on the release layer.
After winding the outermost layer of veneer veneer to form a cylindrical body,
The elastic belt-shaped belt is wound spirally while applying tension around the cylindrical body, and the outer peripheral surface of the cylindrical body is covered with the belt-shaped belt, and both ends of the belt-shaped belt are temporarily fixed to the cylindrical body,
Further, the tubular body and the belt-like belt are integrally removed from the mandrel, and in this state, the adjacent belt-like veneers are bonded together inside and outside.

According to the method of manufacturing a wooden cylinder of the present invention, after the outermost layer of the band-shaped veneer is wound to form a cylindrical body, the elastic belt-shaped belt is applied while tension is applied around the cylindrical body. Spirally wound and covered the outer peripheral surface of the cylindrical body with a belt belt,
Temporarily fixing both ends of the belt-shaped belt to the tubular body, and removing the tubular body and the belt-shaped belt from the mandrel integrally with each other, and adhering the adjacent belt-like veneers inside and outside in this state. It is made of an elastic body wound around the cylindrical body by applying tension around the cylindrical body until the adjacent strip-shaped veneers are bonded inside and outside after the cylindrical body is removed from the mandrel. By the action of the belt-shaped belt, it is possible to continue to apply the tightening pressure necessary for bonding to the cylindrical body. Therefore, the winding pressure of the band-shaped veneer is prevented from being loosened until the adjacent band-shaped veneer is bonded inside and outside, and as a result, the occurrence of an adhesion defect between the inside and outside of the adjacent band-shaped veneer is prevented. You.

Further, a release layer made of a metal tube, a tubular member,
Simple belt and belt belt from three mandrel
Can be removed. And take it from the mandrel
Heating when removing adjacent strips inside and outside after removal
When accompanied by a release layer, the release layer thermally expands and forms a cylindrical body from the inside.
Pressure is applied, and as a result, the adhesive strength is further improved.

In the method for manufacturing a wooden cylinder according to the present invention, the right
The twisted veneer and the left-handed veneer are alternately
May be wound around the drain. Where the right twist
And vice versa are alternately wound one by one.
It is reasonable to turn it,
Is also good. When winding one sheet at a time, twist right
The total number of veneer veneers and the total number of left veneer veneers
May be the same or different.

In this case, the tensile load and the compressive load in the axial direction are reduced.
Young's modulus decreases, torsional deformation occurs, and
Strength due to cracks in the fiber and fiber directions
Can be suppressed, and how to twist left
Torsional deformation and right-hand torsion
Is different from the torsional deformation under the torsional load in the
It becomes.

Further, in the method for manufacturing a wooden cylinder according to the present invention, an adhesive of a heat-curable type is used.
Adhesive between the strips adjacent to each other inside and outside
And removing the metal tube from the mandrel
Therefore, the metal tube, tubular body, and belt belt
Including removing from the barrel and heating in this state
Is preferred.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings.

1 to 6 show the method of the present invention in the order of steps, and FIG. 7 shows a wooden tube manufactured by the method of the present invention.

In FIG. 7, a wooden tube (1) is formed by spirally and laminating a plurality of band-shaped veneers (2) each having a grain extending in a width direction. It is composed of a wound layer (4) of layers, for example, an even number of strips (2). The inner and outer adjacent strip-shaped veneers (2) are bonded together with an adhesive. The side edges of the strip-shaped veneer (2) in each roll (4) are abutted. The side edges of the veneer veneer (2) can be abutted against each other when the two sides of the veneer (2) are in contact with each other, or by processing both sides of the veneer (2) toward the tip. In some cases, a gradually changing thickness portion having a reduced thickness is formed, and the gradually changing thickness portions are overlapped with each other. The diameter of the wooden tube (1) and the thickness of the peripheral wall are appropriately determined according to the purpose of use. Also, the thickness and width of each band-shaped veneer (2) are appropriately determined according to the purpose of use.

Further, a strip-shaped veneer of the innermost roll (4)
(2) is wound with a left-hand twist, and the next wound
The strip-shaped veneer (2) of (4) is wound so as to be twisted right. In the wooden tube (1), a strip-shaped veneer (2) wound to be twisted leftward and a veneer (2) wound to be twisted rightward are alternately arranged one by one. And it exists so that it may each become the same number in total. However, the total number of strip-shaped veneers (2) wound to form a left-hand twist and the total number of band-shaped veneers (2) wound to form a right-hand twist depend on the application and purpose. It may be different.

Each strip-shaped veneer (2) is formed by sewing a thread, and a reinforcing portion (3) extending in the length direction thereof is provided.
, One at each of the portions near both side edges. As the yarn, a yarn made of polyester, rayon, cotton, or the like is used, but is not limited thereto. Also, the upper thread and the lower thread that have been sewn may be equally tensioned, but by making the tension applied to one of the threads greater than the tension applied to the other thread, The breaking effect of the veneer (2) is excellent. The reinforcing portion is not limited to one formed by sewing a thread, but is excellent in reinforcing effect of the band-shaped veneer (2) and breaking prevention effect, and hinders winding of the band-shaped veneer (2). If not, a tape formed of, for example, a cloth or a non-woven fabric may be attached or sewn.

The wooden tube (1) is manufactured as shown in FIGS. 1 to 6 in the following description.
Is called the front, the opposite side is called the rear, and the lower side of FIGS. 1 to 6 is called the left side, and the opposite side is called the right side.

A horizontal mandrel extending in the front-back direction in advance
A metal tube (11) is fitted around the entire length of (10). The metal tube (11) is kept from rotating with respect to the mandrel (10). The metal tube (11) forms a release layer having a thermal expansion property that simplifies the work of removing a tubular body (16) described later from the mandrel (10). Also, at the left front end and the right rear end of the mandrel (10),
The wound products (12A) (12B) of the band-shaped veneers (2) are arranged so as to be movable in the front-rear direction. Although not shown in FIGS. 1 to 6, the band-shaped veneer (2) has a grain extending in the width direction thereof, and the band-shaped veneer (2) is formed by sewing a thread and has a length corresponding to the length of the wood. Reinforcement that extends in the vertical direction
(3) are provided.

First, the mandrel (10) is rotated around its axis in the direction indicated by the arrow X in FIG. 2 to FIG. 5 (clockwise as viewed from the front), and the left side of the mandrel (10) is wound. The strip-shaped veneer (2) unwound from the product (12A)
The metal tube (11) fitted over the mandrel (10) by moving the rolled product (12A) backward while feeding it to the upper side of the mandrel (10) so as not to meander from the left side of the rear.
Wrap the band-shaped veneer (2) so that it is twisted to the left (see Fig. 2), and cut the veneer veneer (2) when the rolled product (12A) comes to the rear end of the mandrel (10). (Step A) (see FIG. 3). In this way, a wound material (13) is formed around the entire length of the metal tube (11). In the wound material (13), one side edge of the band-shaped veneer (2) abuts the other side edge. The wound product (12A) is returned to the front end side of the mandrel (10).

Next, the winding product (1) on the right side of the mandrel (10)
After applying an adhesive to the upper surface of the veneer veneer (2) drawn out from 2B), the veneer veneer (2) is supplied to the lower side of the mandrel (10) so that it does not meander from the front diagonally right side. By moving the rolled product (12B) forward, the strip-shaped veneer (2) is twisted right around the winding (13) formed around the metal tube (11) in the process A. And wound up (12
When B) comes to the front end of the mandrel (10), the strip-shaped veneer (2) is cut (step B) (see FIG. 4). Thus, the roll (1
A winding (14) is formed around the entire length of (3). In the roll (14), one side edge of the band-shaped veneer (2) abuts the other side edge. The rolled product (12B) is returned to the rear end of the mandrel (10).

Next, an adhesive is applied to the lower surface of the strip-shaped veneer (2) unwound from the left take-up product (12A) located at the front end of the mandrel (10), and then the veneer (2) Is supplied to the upper side of the mandrel (10) so that it does not meander from the left side of the rear, and the wound product (12A) is moved backward, so that the wound product (14) formed in the step B is Wind the strip-shaped veneer (2) so that it is twisted to the left, and take it up
When comes to the rear end of the mandrel (10), the strip-shaped veneer (2) is cut (step C) (see FIG. 5). In the roll (15)
One side edge of the band-shaped veneer (2) abuts the other side edge. The wound product (12A) is returned to the front end side of the mandrel (10).

In the steps A, B and C, when the veneer veneer (2) is wound, the veneer veneer (2) may crack along the grain. Even if it does, the function of the reinforcing portion (3) makes the belt-shaped veneer (2) intermittent, but can be wound without hindrance.

After the process A, the process B and the process C are repeated a predetermined number of times, and finally the process B is completed, so that the wound material (13) (14) ) (15)
Is formed, and an adhesive is interposed between the adjacent band-shaped veneers (2) inside and outside. Therefore, in the cylindrical body (16), the single veneer (2) wound to be twisted left and the single veneer (2) wound to be twisted right are alternately arranged. And the same number in total. However, the total number of strip-shaped veneers (2) wound to form a left-hand twist and the total number of band-shaped veneers (2) wound to form a right-hand twist depend on the application and purpose. It may be different. As the adhesive, a heat-curable adhesive such as a phenol-based, amino-based, or isocyanate-based resin adhesive, or a room-temperature-dryable adhesive such as a wood adhesive is used.

Next, after winding the outermost layer of the veneer veneer (2) to form a roll, the belt (17) made of an elastic material is placed on the tubular body (16) while rotating the mandrel (10). Is wound spirally while applying tension to the periphery of the cylindrical body, and the outer peripheral surface of the tubular body (17) is covered with the belt-shaped belt (17). Next, the rotation of the mandrel (10) is stopped, and the both ends of the belt-shaped belt (17) are stopped by a stop ring (18).
To temporarily fix to the cylindrical body (16). The elastic belt belt (17) has a tensile strength of at least 100 kg / cm.
As described above, it is preferable to use an elastic material such as rubber having a characteristic that the tension at 1% elongation is 3 to 35 kgf / cm.

Next, by pulling out the metal tube (11) from the mandrel (10), the metal tube (11), the tubular body (16) and the belt belt (17) are integrally removed from the mandrel (10). Put into a heating furnace and heat. The heating temperature is 140 to 160 ° C. when the adhesive is a phenol resin adhesive, 130 to 140 ° C. when the melamine resin adhesive is used, and 60 to 100 ° C. when the nosorcinol, isocyanate resin adhesive, or urea resin adhesive is used. . During the above heating,
The metal tube (11) thermally expands and pressure is applied to the tubular body (16) from inside, and as a result, the adhesive is applied while applying pressure from both inside and outside together with the tightening pressure from the outside of the belt belt (17). Can be cured. When the adhesive is cured by heating, the belt-like belt (17) is peeled off from the tubular body (16), and the tubular body (16) is loosened by using a special extrusion device or by giving humidity to the metallic tube ( Remove from 11). Thus, a wooden tube (1) is manufactured.

[Brief description of the drawings]

FIG. 1 is a plan view showing an arrangement of a mandrel and a strip-shaped single plate wound product for manufacturing a wooden tube.

FIG. 2 is a plan view showing a state where an innermost band-shaped veneer is wound.

FIG. 3 is a plan view showing a state where winding of an innermost band-shaped veneer is completed.

FIG. 4 is a plan view showing a state where winding of a second band-shaped veneer from the inside is completed.

FIG. 5 is a plan view showing a state where winding of a third band-shaped veneer from the inside is completed.

FIG. 6 is a plan view showing a state where an elastic belt-shaped belt is wound around a formed tubular body.

FIG. 7 is a partially cutaway perspective view showing a wooden cylinder manufactured by the method of the present invention.

[Explanation of symbols]

 (1): Wooden tube (2): Strip veneer (10): Mandrel (11): Metal tube (peeling layer) (16): Tubular body (17): Elastic belt belt

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Jun Sato 8-14 Ryuzoji-cho, Chuo-ku, Osaka-shi, Osaka Prefecture Showa Marutsunai Co., Ltd. (72) Ryo Takenaka 8-14 Ryuzoji-cho, Chuo-ku, Osaka-shi, Osaka No. Showa Marutsunai Co., Ltd. (72) Inventor Toshiki Shizuno 8-14 Ryuzoji-cho, Chuo-ku, Osaka, Osaka Prefecture Showa Marutsunai Co., Ltd. (72) Akihiro Nakayama 8-14 Ryuzoji-cho, Chuo-ku, Osaka, Osaka No. Showa Marutsunai Co., Ltd. (56) References JP-A-8-105155 (JP, A) JP-A-55-128407 (JP, A) Patent 169726 (JP, C1) (58) Fields investigated (Int. Cl. ⁷ , DB name) B27M 1/00-3/38

Claims (3)

(57) [Claims] 1. A plurality of wooden veneers are sequentially wound spirally around a mandrel in a stacked manner such that right-handed ones and left-handed ones coexist. A method for manufacturing a wooden cylinder including forming a tubular body and interposing an adhesive between adjacent strip-shaped veneers inside and outside, wherein the innermost band-shaped veneer is a mandrel.
Before wrapping around the mandrel, place a metal tube around the mandrel.
To form a release layer with thermal expansion
After forming a tubular body on this release layer , winding the outermost layer of veneer veneer to form a tubular body, and then applying an elastic belt-shaped belt, applying tension around the tubular body Spirally wound and covered the outer peripheral surface of the tubular body with a belt-like belt, temporarily fixing both ends of the belt-like belt to the tubular body, and removing both the tubular body and the belt-like belt from the mandrel as one body, A method for manufacturing a wooden cylinder, comprising bonding adjacent strip-shaped veneers inside and outside in a state. 2. The method for manufacturing a wooden cylinder according to claim 1, wherein a right-handed strip-shaped veneer and a left-handed strip-shaped veneer are alternately wound around a mandrel. 3. Use of a heat-curable adhesive
That this adhesive is applied between adjacent strips inside and outside
And remove the metal tube from the mandrel.
Metal tube, tubular body and belt belt
Remove from the mandrel and heat in this state.
The method for producing a wooden cylinder according to claim 1 , comprising :