Wooden frame members and their manufacturing methods

Abstract

To provide a wooden shaft member and a method for manufacturing the same, which has a joint portion in which the end of a lag screw bolt embedded in a pre-drilled hole of the wooden shaft member makes metal-to-metal contact with two other members, allowing for bolted connection, and which can withstand both tensile and compressive forces acting from other members. [Solution] The wooden shaft member 70 comprises a wooden material 10 and a bolt unit 40 screwed into its pre-drilled hole 16, and has joints 60A and 60B that are joined to other members. The bolt unit 40 has two lag screw bolts 30 and a first bolt 20, and the second male threads 22 on both ends of the first bolt 20 are screwed into the first female threads 36 of the two lag screw bolts 30, and the first female threads 37 of the two lag screw bolts 30 face the first end face 12 and the second end face 14 of the wooden material 10, respectively, and the second bolt 50A and the third bolt 50B are screwed in from the outside of the first end face 12 and the second end face 14 to form joints 60A and 60B.

Description

Technical Field

[0001] The present invention relates to a wooden shaft member and a method for manufacturing the same. Background Art

[0002] In wooden buildings constructed by the wood frame construction method, earthquake resistance and other properties are improved by joining the joints of wooden shaft members forming columns, beams, foundations and the like to each other via joining metal fittings to tightly bind the members to each other.

[0003] Examples of joining methods using the above joining metal fittings include lag screw bolt joining using lag screw bolts provided with external threads on the outer periphery, and GIR (Glued in Rod) joining in which a metal rod is inserted into a prepared hole after the prepared hole is filled with an adhesive for joining. In any of these joining methods, by applying large-diameter bolts or metal rods, the joints of a plurality of wooden shaft members to be joined can be joined to each other with high strength.

[0004] By the way, inside the wooden shaft member, the above-mentioned lag screw bolt is embedded so as to penetrate a pair of opposing end faces (for example, a pair of end faces in the depth direction of a wooden beam), steel plates or the like of another member (for example, a pair of wooden columns) are disposed on both of the pair of end faces, and when joining a wooden beam that is a wooden shaft member and a wooden column that is another member by screwing bolts into female threads provided at both ends of the lag screw bolt, it often occurs that both ends of a single lag screw bolt are joined in a state where they are not in metal contact with the corresponding steel plates or the like.

[0005] As described above, when both ends of the lag screw bolt are not in metal contact with the corresponding steel plates or the like of the other member, although the wooden shaft member can resist the pulling force acting from the other member, it becomes difficult to resist the acting compressive force.

[0006] In reality, considering that wooden timber members expand and contract due to changes in moisture content, it is difficult to perfectly match the length between a pair of end faces of a wooden timber member (for example, the beam depth of a wooden beam) with the length of the lag screw bolt embedded in the wooden timber member. Therefore, it is extremely difficult to manufacture a wooden timber member in which a lag screw bolt of the same length as the pre-drilled hole is embedded so that both ends of the lag screw bolt can make metal-to-metal contact with the corresponding other member.

[0007] Therefore, a wooden shaft member and a method for manufacturing it are desired, which have a joint where the ends of lag screw bolts embedded in the pre-drilled holes of the wooden shaft member face a pair of opposing end faces of the wooden shaft member, and the ends of the lag screw bolts make metal-to-metal contact with two other members arranged on the pair of end faces, allowing for bolted connection, and which can withstand both tensile and compressive forces acting from the other members.

[0008] Here, Patent Document 1 proposes a method for installing lag screw bolts. This method involves embedding a lag screw bolt in a pilot hole drilled in the connecting end of a cross-laminated board, creating a recessed female thread portion at the rear end of the lag screw bolt for screwing in a connecting bolt or mounting jig, forming a thread from the side of the rear end of the lag screw bolt towards the tip, and shaping the root diameter of the thread to match the dimensions of the pilot hole in the cross-laminated board. This method is for installing lag screw bolts in wood-steel hybrid structures.

[0009] The mounting jig is attached to the female thread portion of the lag screw bolt. The jig comprises a tightening bolt body having a male thread portion that screws into the female thread portion of the lag screw bolt and a head that connects to a rotary tool, a retaining cylinder body that passes through the male thread portion of the tightening bolt body and extends from the underside of the head of the tightening bolt body to the orthogonal laminated plate side, and a stop plate disposed between the retaining cylinder body and the rear end of the lag screw bolt. The lag screw bolt is then screwed into the pilot hole with the tightening bolt body until the stop plate contacts the orthogonal laminated plate. Finally, the retaining cylinder body is fixed with a fixing tool, and the tightening bolt body is removed from the female thread portion of the lag screw bolt. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2022-129431 [Overview of the project] [Problems that the invention aims to solve]

[0011] While the method for installing lag screw bolts described in Patent Document 1 makes it easier to embed lag screw bolts in pre-drilled holes in wood, it does not address the above-mentioned problem, namely, it does not propose a wooden shaft member that can withstand both tensile and compressive forces acting from other members.

[0012] The present invention has been made in view of the above-mentioned problems, and aims to provide a wooden shaft member and a method for manufacturing the same, wherein the ends of lag screw bolts embedded in the pre-drilled holes of the wooden shaft member face a pair of opposing end faces of the wooden shaft member, and the ends of the lag screw bolts make metal-to-metal contact with two other members arranged on the pair of end faces, enabling bolted connection, thereby resisting both tensile and compressive forces acting from other members. [Means for solving the problem]

[0013] To achieve the above objective, one embodiment of the wooden slat member according to the present invention is: A wooden shaft member comprising a wooden material and a bolt unit screwed into a pre-drilled hole in the wooden material, and having a joint portion that connects to other members, The wood material has a pair of first and second end faces that come into contact with the other member, A pre-hole is provided inside the wood material, penetrating between the first end face and the second end face. The bolt unit is It comprises two lag screw bolts having a first male thread on its outer circumference and a first female thread inside, and a first bolt having a second male thread at least on both ends, formed by the second male threads on both ends of the first bolt screwing into the first female threads of the two lag screw bolts. The first female threads of both of the two lag screw bolts face the first and second end faces, respectively, and the second bolt and the third bolt are screwed into the first and second end faces from the outside, respectively, to form the joint.

[0014] According to this embodiment, instead of embedding a single lag screw bolt in the pre-drilled hole of the wood material, a bolt unit in which two lag screw bolts are joined by a bolt (first bolt) is screwed into the pre-drilled hole, and bolts (second bolt and third bolt) are screwed into the female threads (first female thread) of both lag screw bolts from the outside of a pair of opposing end faces (first and second end faces) of the wood material, respectively, forming a joint on the pair of end faces. This allows metal-to-metal contact between the ends of the two lag screw bolts and the steel plates or other materials of other members. As a result, a wood shaft member can be formed that can withstand both tensile and compressive forces acting from other members.

[0015] Here, "joint" refers to a combination of a lag screw bolt and a second or third bolt that screws into the first female thread, which forms a means for joining with other members at both the first and second end faces of a pair of wooden members. For example, in the case of a wooden beam, a pre-drilled hole is machined inside the wooden beam in the direction of its beam depth, a bolt unit is embedded in the pre-drilled hole, and steel plates attached to the ends of two wooden columns, which are other members, come into contact with the first and second end faces of the wooden beam, respectively, and each steel plate is bolted in a metal-to-metal contact position with the end of the corresponding lag screw bolt.

[0016] The bolt unit is screwed into the pre-drilled hole by screwing the second male thread of the first bolt into the first female thread of both lag screw bolts, so that the total length of the bolt unit is approximately the distance between the first and second end faces of the wood material. In other words, since the total length of the bolt unit is adjustable, it can be flexibly adapted to the distance between the first and second end faces of the wood material to which it is applied.

[0017] Furthermore, in another embodiment of the wood-frame member according to the present invention, The lag screw bolt is characterized by having a partition wall inside, and having two of the first female threads on both sides of the partition wall.

[0018] According to this embodiment, the lag screw bolt has a partition wall inside, and two first female threads on both sides of the partition wall. This eliminates a manufacturing defect in which, when the bolt unit is screwed into the pre-drilled hole, for example, the lag screw bolt located forward in the screwing direction stops moving midway through the pre-drilled hole, and the first bolt engages with the first female thread, preventing the entire bolt unit from being embedded in the entire (or nearly entire) area of ​​the pre-drilled hole. In other words, even if the lag screw bolt located forward in the screwing direction stops moving midway through the pre-drilled hole, the tip of the first bolt will come into contact with the partition wall as the first bolt is screwed into the first female thread, and the first bolt will push the partition wall in the screwing direction, allowing the entire bolt unit to be embedded in the entire area of ​​the pre-drilled hole.

[0019] Furthermore, in another embodiment of the wood-frame member according to the present invention, The two lag screw bolts are characterized by having the same overall dimensions, including length, and external shape.

[0020] According to this embodiment, the bolt unit formed by screwing the second male thread of the first bolt into the first female thread of both of the two lag screw bolts has an adjustable overall length. Therefore, it is possible to use the same type of lag screw bolts with the same overall dimensions, including length, and external shape, while accommodating wood materials with varying lengths between the first and second end faces (length of the pre-drilled holes that penetrate the first and second end faces).

[0021] Furthermore, other embodiments of the wooden shaft member according to the present invention are: The steel plates of the other member abut against both the first and second end faces, the ends of the two lag screw bolts are in metal-to-metal contact with each of the steel plates, and the second bolt and the third bolt are screwed into the first female thread through bolt holes provided in each of the steel plates.

[0022] According to this aspect, steel plates provided on another member abut against both the first end face and the second end face of the wooden material respectively, the ends of the two lag screw bolts make metal contact, and the second bolt and the third bolt are screwed into the corresponding first internal threads of the lag screw bolts through bolt holes provided in the respective steel plates to form a joint, whereby a wooden shaft member that can resist both a pulling-out force and a compressive force acting from another member can be formed.

[0023] Furthermore, one aspect of a method for manufacturing a wooden shaft member according to the present invention is: A method for manufacturing a wooden shaft member, comprising a wooden material and a bolt unit screwed into a prepared hole of the wooden material, the wooden shaft member having a joint portion to be joined to another member, wherein the wooden material includes a pair of the first end face and the second end face that abut against the other member, the bolt unit includes: two lag screw bolts each having a first external thread on an outer periphery and a first internal thread inside, and a first bolt having second external threads on at least both end sides, wherein the bolt unit is formed by the two second external threads on both end sides of the first bolt being screwed into the first internal threads of the two lag screw bolts, a prepared hole forming step of forming the prepared hole penetrating between the first end face and the second end face inside the wooden material; a bolt unit installation step of forming the joint portion on the first end face side by screwing a second bolt into the first internal thread of one of the two lag screw bolts constituting the bolt unit, rotating the second bolt to screw the bolt unit into the prepared hole from the outside of the first end face; a forming step of forming the joint portion on the second end face side by screwing a third bolt from the outside of the second end face into the first internal thread of the other of the two lag screw bolts,

[0024] According to this embodiment, a bolt unit is prepared in which two lag screw bolts are joined by a bolt (first bolt) and a pre-drilled hole is formed through the opposing first and second end faces of a wooden material. The second bolt is screwed into the female thread (first female thread) of one lag screw bolt from the outside of the first end face, and the bolt unit is screwed into the pre-drilled hole by rotating the second bolt. Then, the third bolt is screwed into the female thread (first female thread) of the other lag screw bolt from the outside of the second end face, thereby producing a wooden shaft member in which joints with other members are formed on the first and second end faces of the wooden material, respectively.

[0025] Even if, when the bolt unit is screwed into the pre-drilled hole, the end face of the lag screw bolt at the front in the screwing direction is not flush with the second end face and is located inside the pre-drilled hole, by screwing the third bolt into the first female thread of the lag screw bolt from the outside of the second end face, the lag screw bolt rotates relative to the first bolt and moves toward the second end face. As a result, the end face of the lag screw bolt can be made flush with the second end face, and the end faces of the corresponding lag screw bolts can be set flush with both the first and second end faces, making it possible to make metal-to-metal contact between the end faces of each lag screw bolt and other components (such as the steel plates they comprise). [Effects of the Invention]

[0026] As can be understood from the above explanation, according to the wooden shaft member and its manufacturing method of the present invention, the ends of the lag screw bolts embedded in the pre-drilled holes of the wooden shaft member face a pair of opposing end faces of the wooden shaft member, and the ends of the lag screw bolts make metal-to-metal contact with two other members arranged on the pair of end faces, providing a joint that can be bolted together, thereby enabling the manufacture of a wooden shaft member that can withstand both tensile and compressive forces acting from other members. [Brief explanation of the drawing]

[0027] [Figure 1A] This is a process diagram of an example of a method for manufacturing a wooden slat member according to an embodiment. [Figure 1B] This is a view from arrow BB in Figure 1A. [Figure 2] Following Figure 1A, this is a process diagram illustrating an example of a method for manufacturing a wooden slat member according to the embodiment. [Figure 3] Following Figure 2 is a process diagram illustrating an example of a method for manufacturing a wooden slat member according to this embodiment. [Figure 4] Following Figure 3 is a process diagram illustrating an example of a method for manufacturing a wooden slat member according to this embodiment. [Figure 5] Following Figure 4, the next diagram is a process diagram of an example of a method for manufacturing a wooden shaft member according to the embodiment, and is a longitudinal cross-sectional view of an example of a wooden shaft member according to the embodiment. [Figure 6] This is a longitudinal cross-sectional view showing a column-beam joint structure to which an example of a wooden axial member according to the embodiment is applied. [Figure 7] This is a longitudinal cross-sectional view showing a reinforcing structure around a through-hole in a beam, to which an example of a wooden axial member according to the embodiment is applied. [Figure 8] This diagram illustrates the method for removing bolt units from wooden structural members when disposing of them. [Modes for carrying out the invention]

[0028] The wooden stile member and its manufacturing method according to the embodiment will be described below with reference to the attached drawings. In this specification and drawings, substantially identical components may be denoted by the same reference numerals to avoid redundant explanations.

[0029] [An embodiment of a wooden frame member and its manufacturing method] Referring to Figures 1 to 8, a wooden stile member according to an embodiment and its manufacturing method will be described. Here, Figures 1A, 2 to 5 are, in order, process diagrams of an example of the manufacturing method of the wooden stile member according to the embodiment. Figure 6 is a longitudinal cross-sectional view showing a column-beam joint structure to which an example of the wooden stile member according to the embodiment is applied, and Figure 7 is a longitudinal cross-sectional view showing a reinforcing structure around a beam through-hole to which an example of the wooden stile member according to the embodiment is applied.

[0030] This document details one example of a method for manufacturing a timber frame member. In this example, the timber frame member being manufactured is a timber beam including a base, and the other members joined at the joints of the timber beam are timber columns. However, the timber frame member and the other members joined to it may be members other than those shown in the example.

[0031] As shown in Figures 1A and 1B, a pre-drilled hole 16 is machined inside the wood material 10, extending through the beam in the direction between the first end face 12 and the second end face 14. Both the first end face 12 and the second end face 14 are end faces that abut against other members. Here, "other members" include not only members such as wooden beams and wooden columns, but also steel plates that form mounting brackets (pre-drilled hole formation process).

[0032] Next, as shown in Figure 2, a bolt unit 40 is prepared to be screwed into the pre-drilled hole 16 of the wood material 10.

[0033] The bolt unit 40 comprises two lag screw bolts 30A and 30B, each having a first male thread 32 on its outer circumference and two first female threads 36 and 37 inside via a partition wall 34, and a first bolt 20 (fully threaded bolt) having a second male thread 22 along its entire outer circumference. The bolt unit is formed by screwing the second male thread 22 of the first bolt 20 into the first female threads 36 of the two lag screw bolts 30A and 30B. In the illustrated example, the first bolt 20 is a fully threaded bolt, but it may also be a double-threaded bolt with second male threads only on both ends.

[0034] The overall length of the bolt unit 40 can be changed by adjusting the threading length of the first bolt 20 into the first female threads 36 of both of the two lag screw bolts 30.

[0035] The two lag screw bolts 30A and 30B in the illustrated example are identical lag screw bolts with the same overall dimensions, including length, and external shape. In this way, by applying identical lag screw bolts 30, it is possible to form a bolt unit 40 that can accommodate various beam depths (length between the first end face 12 and the second end face 14) (same length as the beam depth).

[0036] The second bolt 50A is screwed in the X1 direction into the first female thread 37 of one of the lag screw bolts 30A that make up the bolt unit 40, and the second bolt 50A is rotated to screw the bolt unit 40 into the pre-drilled hole 16 from the outside of the first end face 12 of the wood material 10 in the X2 direction.

[0037] In this case, with the second bolt 50A screwed into the bolt hole Pa of the steel plate P1, which is fixed to another member (not shown), the second bolt 50A is screwed into the first female thread 37 of the lag screw bolt 30A. That is, with the second bolt 50A screwed into the first female thread 37, the end 38 of the lag screw bolt 30A is in a metal-to-metal contact position with the steel plate P1.

[0038] As shown in Figure 3, by screwing the bolt unit 40 into the pre-drilled hole 16 of the wood material 10 in the X3 direction, the bolt unit 40, which has a length t2 that is slightly shorter than the length t1, is screwed into the pre-drilled hole 16, which has a length t1, and a position is formed in which the steel plate P1 is in contact with the first end face 12 of the wood material 10 and the end 38 of the lag screw bolt 30A.

[0039] In the wood material 10, where the steel plate P1 is in contact with the first end face 12 and the end 38 of the lag screw bolt 30A, the steel plate P1 is sandwiched between the lag screw bolt 30A and the second bolt 50A to form a joint 60A.

[0040] Since the length t2 of the bolt unit 40 (the length when screwed into the pre-hole 16) is set shorter than the length t1 of the pre-hole 16, a gap G1 is created on the second end face 14 side of the pre-hole 16 when the bolt unit 40 is fully screwed into the pre-hole 16.

[0041] For example, if a lag screw bolt does not have an internal partition and the first female thread is a through hole, when the bolt unit is screwed into the pre-drilled hole, the lag screw bolt, which is forward in the screwing direction, may stop moving midway through the pre-drilled hole, causing the first bolt to screw into the first female thread, which is a through hole. This can result in a manufacturing defect where the entire bolt unit cannot be completely embedded in the pre-drilled hole.

[0042] In contrast, the lag screw bolt 30 in the illustrated example has a partition wall 34 inside, and two first female threads 36 and 37 on both sides of the partition wall 34. Therefore, even if the lag screw bolt 30B, which is located forward in the screwing direction, stops moving midway through the pre-drilled hole 16, the tip of the first bolt 20 will come into contact with the partition wall 34 when the first bolt 20 is screwed into the first female thread 36, causing the first bolt 20 to push the partition wall 34 in the screwing direction. This pushing allows the bolt unit 40 to be completely embedded in the pre-drilled hole 16 without stopping the forward movement of the bolt unit 40 (the above is the bolt unit installation process).

[0043] Next, as shown in Figure 4, the third bolt 50B is screwed into the first female thread 37 of the other lag screw bolt 30B from the outside of the second end face 14 of the wood material 10 in the X4 direction (counterclockwise). Here, by placing an anti-rotation nut (not shown) in the gap G1 and screwing in the third bolt 50B, the screwing of the third bolt 50B can be performed smoothly.

[0044] When screwing in the third bolt 50B, the third bolt 50B is screwed into the first female thread 37 of the lag screw bolt 30B while the third bolt 50B is screwed into the bolt hole Pa of the steel plate P2, which is fixed to another member (not shown).

[0045] As shown in Figure 5, by screwing the third bolt 50B into the first female thread 37 of the lag screw bolt 30B, one lag screw bolt 30A and the first bolt 20, which are embedded inside the pilot hole 16, maintain their embedded position, while the end 38 of the other lag screw bolt 30B moves in the X5 direction to the second end face 14, and the end 38 comes into metal-to-metal contact with the steel plate P2 that is in contact with the second end face 14.

[0046] Furthermore, as the other lag screw bolt 30B moves relative to the first bolt 20, the length of the bolt unit 40 and the length of the pilot hole 16 become the same, and a gap G2 that did not originally exist is created between the partition wall 34 and the end of the first bolt 20 in the first female thread 36.

[0047] In the wood material 10, where the steel plate P2 is in contact with the second end face 14 and the end 38 of the lag screw bolt 30B, the steel plate P2 is sandwiched between the lag screw bolt 30B and the third bolt 50B to form a joint 60B.

[0048] In this way, the steel plates P1 and P2 of the other member abut against both the first end face 12 and the second end face 14 of the wood material 10, and the ends 38 of the two lag screw bolts 30A and 30B that form the bolt unit 40 make metal-to-metal contact with the respective steel plates P1 and P2, and the second bolt 50A and the third bolt 50B are screwed into the respective first female threads 37 through the bolt holes Pa provided in the respective steel plates P1 and P2 to form joints 60A and 60B, thereby manufacturing the wood shaft member 70 (forming process).

[0049] In the case of the wooden shaft member 70, the ends 38 of the two lag screw bolts 30A and 30B embedded in the internal pre-drilled holes 16 are fastened with the second bolt 50A and the third bolt 50B in a metal-to-metal contact position with the steel plates P1 and P2 on the end faces of other members, thereby creating a wooden shaft member that can withstand both the tensile force N1 and the compressive force N2 acting from other members.

[0050] Furthermore, as already explained, by applying a bolt unit 40 in which two lag screw bolts 30 are screwed onto both ends of a first bolt 20, the length of the bolt unit 40 can be adjusted as desired by adjusting the screw length between the first bolt 20 and the two lag screw bolts 30. In this way, while applying two identical lag screw bolts 30 with the same overall dimensions and external shape, it is possible to create a bolt unit 40 with the same length as the length of the pre-drilled hole 16 between the opposing pair of first end faces 12 and second end faces 14 for timber beams of various beam depths, and the ends 38 of the two lag screw bolts 30 can be adjusted to be flush with the first end face 12 and the second end face 14.

[0051] Next, with reference to Figures 6 and 7, we will outline an example of a joint structure between the wooden axial member 70 and other members, and an example of a reinforcing structure around a through-hole provided in the wooden axial member 70.

[0052] Figure 6 shows a column-beam joint structure 90 between a wooden beam 70 (an example of a wooden axial member) and wooden columns 80 (an example of other members) located above and below it.

[0053] The wooden member 10 is provided with multiple pre-drilled holes 16 (for example, two out of four are shown in the illustrated example), and a bolt unit 40 is screwed into each pre-drilled hole 16 to form a wooden beam 70. The steel plates P1 and P2 attached to the ends of the upper and lower wooden columns 80 are fixed by second bolts 50A and third bolts 50B which are screwed into the lag screw bolts 30 of each bolt unit 40.

[0054] Each steel plate P1 and P2, together with a separate steel plate P3 perpendicular to them, forms a T-shaped steel plate unit. The steel plate P3 is embedded in a groove provided inside the end face of the wooden column 80, and the steel plates P1 and P2 are fixed to the end face of the wooden column 80 by inserting drift pins D through pin holes provided in the wooden column 80 and the steel plate P3.

[0055] In the illustrated column-beam joint structure 90, the wooden beam 70 can resist both the tensile force N1 and the compressive force N2 acting from the upper and lower wooden columns 80.

[0056] On the other hand, Figure 7 shows that the wooden beam 70 is provided with a through hole 75 through which pipes, wiring, etc., pass. Multiple pre-drilled holes 16 (for example, two in the illustrated example) are provided around this through hole 75, and a bolt unit 40 is screwed into each pre-drilled hole 16. Common steel plates P1 and P2 are fixed to both bolt units 40 by a second bolt 50A and a third bolt 50B which are screwed into the lag screw bolts 30 of each bolt unit 40.

[0057] By providing multiple bolt units 40 around the through-holes 75 in the wooden beam 70, the area around the through-holes 75 is effectively reinforced.

[0058] Furthermore, when the wooden shaft member 70 is used for a certain period and it is time to dispose of it, as shown in Figure 8, the tip of a long push-in bolt B is screwed into the first female thread 37 of one lag screw bolt 30B, and the bolt unit 40 is removed from the other side by rotating the push-in bolt B, thereby separating the wooden material 10 and the bolt unit 40, and both can be disposed of.

[0059] Furthermore, other embodiments may be used in which other components are combined with the configurations listed in the above embodiments, and the present invention is not limited in any way to the configurations shown herein. In this regard, modifications can be made without departing from the spirit of the present invention, and can be appropriately determined according to the application form. [Explanation of symbols]

[0060] 10: Wooden material (wooden beam) 12: First end surface 14:Second end surface 16: Pre-drilled hole 20: First bolt 22: Second male screw 30, 30A, 30B: Lag screw bolts 32: First male screw 34: Bulkhead 36,37: First female thread 38: End 40: Bolt Unit 50A: Second bolt 50B: Third bolt 60A,60B:Joint part 70: Wooden structural member (wooden beam) 75: 80: Other structural members (wooden columns) 90: Column beam joint structure 90A: Reinforcement structure around through holes P1,P2,P3: Steel plate Pa: Bolt hole D: Drift pin G1, G2: Gap N1: Pull-out force N2: Compression force B: Push-in bolt

Claims

1. A wooden shaft member comprising a wooden material and a bolt unit screwed into a pre-drilled hole in the wooden material, and having a joint portion that connects to other members, The wood material has a pair of first and second end faces that come into contact with the other member, A pre-hole is provided inside the wood material, penetrating between the first end face and the second end face. The bolt unit is It comprises two lag screw bolts having a first male thread on its outer circumference and a first female thread inside, and a first bolt having a second male thread at least on both ends, and is formed by screwing the second male threads on both ends of the first bolt into the first female threads of the two lag screw bolts. A wooden shaft member characterized in that the first female threads of both of the two lag screw bolts face the first and second end faces, respectively, and the second bolt and the third bolt are screwed into the first and second end faces from the outside, respectively, to form the joint.

2. The wooden shaft member according to claim 1, characterized in that the lag screw bolt has a partition wall inside and two of the first female threads on both sides of the partition wall.

3. The wooden shaft member according to claim 1 or 2, characterized in that the two lag screw bolts have the same overall dimensions, including length, and external shape.

4. The wooden shaft member according to claim 1 or 2, characterized in that the steel plates of the other member abut against both the first end face and the second end face, the ends of the two lag screw bolts are in metal-to-metal contact with each of the steel plates, and the second bolt and the third bolt are screwed into the first female thread through bolt holes provided in each of the steel plates.

5. A method for manufacturing a wooden shaft member comprising a wooden material and a bolt unit screwed into a pre-drilled hole in the wooden material, and having a joint portion for joining with other members, The wood material has a pair of first and second end faces that come into contact with the other member, The bolt unit is It comprises two lag screw bolts having a first male thread on its outer circumference and a first female thread inside, and a first bolt having a second male thread at least on both ends, and is formed by screwing the second male threads on both ends of the first bolt into the first female threads of the two lag screw bolts. A pre-hole forming step is performed in which a pre-hole is formed in the interior of the wood material, penetrating between the first end face and the second end face. A bolt unit installation step involves screwing a second bolt into the first female thread of one of the two lag screw bolts constituting the bolt unit, and then rotating the second bolt to screw the bolt unit into the pre-drilled hole from the outside of the first end face, thereby forming the joint on the first end face side. A method for manufacturing a wooden shaft member, comprising the step of forming the joint on the second end face side by screwing a third bolt into the first female thread of the other of the two lag screw bolts from the outside of the second end face.

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