Jig for suppressing expansion / contraction of wooden shaft member and method for protecting wooden shaft member
The cover on wooden shaft members suppresses moisture-related expansion and contraction, stabilizing hole positions and preventing cracking by covering end faces and holes, enhancing connection stability.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SEKISUI HOUSE KK
- Filing Date
- 2025-07-14
- Publication Date
- 2026-07-23
AI Technical Summary
Wooden shaft members expand or contract due to moisture absorption or evaporation, causing hole position shifts and potential cracking when connected with drift pins.
A cover is attached to the axial end of the wooden shaft member, featuring a first covering portion to suppress moisture absorption or evaporation on the end face and a second covering portion to cover the holes, preventing expansion and contraction, and a slit is covered to further suppress moisture absorption.
The cover effectively suppresses moisture absorption and evaporation, preventing hole position displacement and reducing the likelihood of cracking during connection with drift pins.
Smart Images
Figure JP2025025203_23072026_PF_FP_ABST
Abstract
Description
Expansion and Contraction Suppression Fixture for Wooden Shaft Member and Method for Protecting Wooden Shaft Member
[0001] The present disclosure relates to an expansion and contraction suppression fixture for a wooden shaft member and a method for protecting a wooden shaft member.
[0002] Patent Document 1 discloses a wooden beam, which is one of the wooden shaft members. The wooden beam is provided with holes extending in a direction intersecting the direction in which the wooden beam extends. A drift pin for connecting the wooden beam to a beam receiving plate is inserted through the holes.
[0003] Japanese Unexamined Patent Application Publication No. 2024-24423
[0004] When water is applied to the wooden shaft member or the wooden shaft member is stored in a humid environment, the wooden shaft member expands by absorbing moisture. When the wooden shaft member is stored in a dry environment, the wooden shaft member contracts as the moisture evaporates. When the wooden shaft member expands or contracts, the position of the hole shifts. If the position of the hole shifts, there is a risk that the wooden shaft member will crack when connecting the wooden shaft member to the beam receiving plate with a drift pin.
[0005] [[ID=]](1) The expansion and contraction suppression fixture for a wooden shaft member according to one aspect of the present disclosure includes a cover attached to an axial end of the wooden shaft member. The axial end face of the wooden shaft member includes a sawn end face. The wooden shaft member is provided with holes extending in a direction intersecting the axial direction and opening on the outer peripheral surface of the wooden shaft member. The cover has a first covering portion that covers the sawn end face and a second covering portion that covers the holes.
[0006] According to this configuration, since the first covering portion of the cover covers the sawn end face, which is a surface where moisture absorption or evaporation is likely to occur, it is possible to suppress moisture absorption or evaporation from the sawn end face of the wooden shaft member. Also, since the second covering portion of the cover covers the holes, it is possible to suppress moisture absorption or evaporation through the holes of the wooden shaft member. Therefore, it is possible to suppress expansion and contraction of the wooden shaft member. As a result, it is possible to suppress displacement of the hole position.
[0007] (2) In the wooden shaft member expansion and contraction suppression jig of (1) above, the cross-sectional shape of the wooden shaft member is square, the outer surface has two first surfaces that form a pair in the direction in which the hole extends, and two second surfaces that form a pair in a direction that intersects both the axial direction and the direction in which the hole extends, and the second covering portion has two first plate portions that contact the two first surfaces and two second plate portions that contact the two second surfaces.
[0008] In this configuration, the two first plate sections sandwich the wooden shaft member in the direction in which the hole extends. The two second plate sections sandwich the wooden shaft member in a direction that intersects both the axial direction and the direction in which the hole extends. Therefore, the cover attached to the axial end of the wooden shaft member is less likely to come off.
[0009] (3) In the wooden shaft member expansion and contraction suppression jig of (2) above, a slit is provided on the end face, the slit extends from one of the second surfaces to the other of the second surfaces, and the second plate portion covers the slit.
[0010] With this configuration, the second plate covers the slit, thus suppressing the absorption or evaporation of moisture through the slit in the wooden shaft member. Therefore, the expansion and contraction of the wooden shaft member can be further suppressed.
[0011] (4) In the wooden shaft member expansion and contraction suppression jig of (3) above, the end face is provided with two slits, the end face has two first end faces as end faces located outside the two slits, a second end face as an end face located between the two slits and recessed relative to the first end faces, and a connecting surface located between the first end faces and the second end faces, and the first covering portion has a first portion that covers the first end faces, a second portion that covers the second end faces, and a third portion that covers the connecting surface.
[0012] With this configuration, the first covering portion has a shape that corresponds to the end face of the wooden shaft member, so the gap between the first covering portion and the end face becomes smaller. Therefore, the expansion and contraction of the wooden shaft member can be further suppressed.
[0013] (5) In any one of the wooden shaft member expansion and contraction suppression fixtures described in (1) to (4) above, the cover is made of metal, resin, rubber, or a composite material thereof. This configuration improves the adhesion of the cover to the wooden shaft member.
[0014] (6) A method for protecting a wooden shaft member according to one aspect of the present disclosure, wherein the wooden shaft member is stored with one of the wooden shaft member expansion and contraction suppression fixtures described in (1) to (5) above attached to the axial end of the wooden shaft member.
[0015] According to this method, the wooden shaft member is stored with the end grain, which is the surface most susceptible to moisture absorption or evaporation, covered by the first covering portion of the cover. Therefore, moisture absorption or evaporation from the end grain of the wooden shaft member can be suppressed. In addition, the wooden shaft member is stored with the holes covered by the second covering portion of the cover. Therefore, moisture absorption or evaporation through the holes of the wooden shaft member can be suppressed. Consequently, expansion and contraction of the wooden shaft member can be suppressed. As a result, misalignment of the holes can be suppressed.
[0016] According to the wooden shaft member expansion and contraction suppression jig and wooden shaft member protection method of this disclosure, the expansion and contraction of the wooden shaft member can be suppressed.
[0017] This is an exploded perspective view showing the framework of a building. This is a plan view showing the framework of a building. This is a perspective view showing the first axial member and the cover attached to the first axial member. This is an exploded perspective view showing the first axial member and the cover.
[0018] Referring to Figures 1 to 4, the expansion and contraction suppression jig 17 for wooden shaft members and the method for protecting wooden shaft members in this embodiment will be described. As shown in Figures 1 and 2, the frame 10 of the building comprises a first shaft member 11, a second shaft member 12, and connecting hardware 13, which are wooden shaft members. The first shaft member 11 and the second shaft member 12 in this embodiment are horizontal members that extend in the horizontal direction. The axial direction of the first shaft member 11 and the axial direction of the second shaft member 12 are perpendicular to each other. The first shaft member 11 and the second shaft member 12 in this embodiment are made of wood.
[0019] The first shaft member 11 is manufactured by cutting wood. The axial direction of the first shaft member 11 is the same as the grain direction of the wood. The axial end face 21 of the first shaft member 11 is formed by the cut surface obtained by cutting the wood in a direction intersecting the grain direction. Therefore, the end face 21 of the first shaft member 11 includes the end grain surface. The end grain surface is the surface where the annual rings are visible.
[0020] The first shaft member 11 is provided with holes 23. In this embodiment, the first shaft member 11 is provided with four holes 23. The holes 23 extend in a direction intersecting the axial direction of the first shaft member 11. In this embodiment, the direction in which the holes 23 extend is perpendicular to the axial direction of the first shaft member 11. The holes 23 open on the outer circumferential surface 22 of the first shaft member 11.
[0021] The cross-sectional shape of the first shaft member 11 in this embodiment is rectangular. The outer circumferential surface 22 of the first shaft member 11 has two first surfaces 22a and two second surfaces 22b. The two first surfaces 22a are paired in the direction in which the hole 23 extends. The first end of the hole 23 opens on one of the first surfaces 22a, and the second end of the hole 23 opens on the other first surface 22a. The two second surfaces 22b are paired in directions that intersect both the axial direction of the first shaft member 11 and the direction in which the hole 23 extends.
[0022] In this embodiment, the end face 21 of the first shaft member 11 is provided with two slits 24. The two slits 24 are spaced apart in the direction in which the hole 23 extends. The slits 24 extend from one second surface 22b to the other second surface 22b. The hole 23 passes through the two slits 24.
[0023] The end face 21 of the first shaft member 11 in this embodiment has two first end faces 21a, a second end face 21b, and two connecting surfaces 21c. The two first end faces 21a and the second end face 21b are surfaces perpendicular to the axial direction of the first shaft member 11. Therefore, the two first end faces 21a and the second end face 21b are end faces. The two first end faces 21a are located outside the two slits 24. The second end face 21b is located between the two slits 24. The second end face 21b is recessed relative to the first end face 21a. The connecting surface 21c is located between the first end face 21a and the second end face 21b. The two connecting surfaces 21c face each other in the direction in which the hole 23 extends.
[0024] The connecting hardware 13 comprises a first plate 31 and two second plates 32 extending from the first plate 31. Each second plate 32 is provided with a plate hole 32a. The first plate 31 is positioned along the side surface 12a of the second shaft member 12. A bolt 14 passes through the second shaft member 12 and the first plate 31. A nut 15 is secured to the bolt 14. This connects the second shaft member 12 and the connecting hardware 13.
[0025] As shown in Figure 2, the two second plates 32 are inserted into the two slits 24 of the first shaft member 11. The nut 15 is located in the space enclosed by the first plate 31, the two second plates 32, and the second end face 21b. The plate hole 32a of the second plate 32 overlaps with the hole 23 of the first shaft member 11. The drift pin 16 is inserted through the hole 23 of the first shaft member 11 and the plate holes 32a of the two second plates 32. This connects the first shaft member 11 and the connecting hardware 13. Therefore, the first shaft member 11 is connected to the second shaft member 12 via the connecting hardware 13.
[0026] <Wooden shaft member expansion and contraction suppression jig> As shown in Figures 3 and 4, the expansion and contraction suppression jig 17 is equipped with a cover 40. The cover 40 is attached to the axial end of the first shaft member 11. The cover 40 is configured to be detachable from the first shaft member 11. The cover 40 in this embodiment is made of silicone rubber. The cover 40 has a first covering portion 41 and a second covering portion 42.
[0027] The first covering portion 41 of this embodiment has a shape corresponding to the end face 21 of the first shaft member 11. The first covering portion 41 has two first parts 41a, a second part 41b, and two third parts 41c. The two first parts 41a, the second part 41b, and the two third parts 41c are each flat. The thickness direction of the two first parts 41a and the second part 41b is the same. When viewed from the thickness direction of the two first parts 41a and the second part 41b, the second part 41b is located between the two first parts 41a. The third part 41c connects the first part 41a and the second part 41b. The thickness direction of the third part 41c is perpendicular to the thickness direction of the two first parts 41a and the second part 41b.
[0028] The second covering portion 42 of this embodiment is rectangular tubular in shape. The second covering portion 42 has two first plate portions 42a and two second plate portions 42b. The two first plate portions 42a and the two second plate portions 42b are each flat. The two first plate portions 42a are facing each other. The two second plate portions 42b are facing each other. The direction in which the two first plate portions 42a are facing each other and the direction in which the two second plate portions 42b are facing each other are perpendicular.
[0029] The axial end of the first shaft member 11 is inserted into the space enclosed by the first covering portion 41 and the second covering portion 42. In this way, the cover 40 is attached to the axial end of the first shaft member 11. The first covering portion 41 covers the end face 21 of the first shaft member 11. The first portion 41a covers the first end face 21a. The second portion 41b covers the second end face 21b. Therefore, the first covering portion 41 covers the end face. The third portion 41c covers the connecting surface 21c.
[0030] The second covering portion 42 covers the outer circumferential surface 22 of the first shaft member 11. The first plate portion 42a covers a part of the first surface 22a. The first plate portion 42a covers the opening of the hole 23. The first plate portion 42a is in contact with the first surface 22a. The second plate portion 42b covers a part of the second surface 22b. In this embodiment, the second plate portion 42b covers the slit 24. The second plate portion 42b is in contact with the second surface 22b.
[0031] <Method for protecting wooden shaft members> After the first shaft member 11 is manufactured, a cover 40 is attached to the axial end of the first shaft member 11. The end face 21 of the first shaft member 11, including the first end face 21a and the second end face 21b, is covered by the first covering portion 41 of the cover 40. The first surface 22a of the first shaft member 11, including the hole 23, is covered by the first plate portion 42a of the second covering portion 42 of the cover 40. The second surface 22b of the first shaft member 11, including the slit 24, is covered by the second plate portion 42b of the second covering portion 42 of the cover 40.
[0032] The first shaft member 11 is stored with the cover 40 of the expansion / contraction suppression jig 17 attached from the time it is manufactured at the factory until it is installed on site. Specifically, the first shaft member 11 is stored at the factory with the cover 40 attached from the time it is manufactured at the factory until it is shipped. The first shaft member 11 is transported from the factory to the site with the cover 40 attached. The first shaft member 11 is stored at the site with the cover 40 attached from the time it is delivered to the site until it is installed. Thus, in this embodiment, since the first shaft member 11 is kept with the cover 40 attached when it is transported from the factory to the site, the state of the first shaft member 11 during transport is considered a form of storage. The cover 40 is removed from the axial end of the first shaft member 11 immediately before installation of the first shaft member 11. The removed cover 40 can be reused on other first shaft members 11.
[0033] [Operation and Effects of this Embodiment] The operation and effects of this embodiment will now be described. (1) The axial end face 21 of the first shaft member 11 includes a first end face 21a and a second end face 21b, which are end faces. The first shaft member 11 is provided with a hole 23 that extends in a direction intersecting the axial direction and opens on the outer circumferential surface 22 of the first shaft member 11. The expansion and contraction suppression jig 17 includes a cover 40 attached to the axial end of the first shaft member 11. The cover 40 has a first covering portion 41 that covers the first end face 21a and the second end face 21b, and a second covering portion 42 that covers the hole 23.
[0034] In this configuration, the first covering portion 41 of the cover 40 covers the first end grain surface 21a and the second end grain surface 21b, which are surfaces prone to moisture absorption or evaporation. Therefore, the absorption or evaporation of moisture from the first end grain surface 21a and the second end grain surface 21b of the first shaft member 11 can be suppressed. Furthermore, the second covering portion 42 of the cover 40 covers the hole 23. Therefore, the absorption or evaporation of moisture by the first shaft member 11 through the hole 23 can be suppressed. Consequently, the expansion and contraction of the first shaft member 11 can be suppressed. As a result, displacement of the hole 23 can be suppressed.
[0035] (2) The cross-sectional shape of the first shaft member 11 is rectangular. The outer circumferential surface 22 of the first shaft member 11 has two first surfaces 22a and two second surfaces 22b. The first surfaces 22a are paired in the direction in which the hole 23 extends. The two second surfaces 22b are paired in a direction that intersects both the axial direction and the direction in which the hole 23 extends. The second covering portion 42 has two first plate portions 42a that contact the two first surfaces 22a and two second plate portions 42b that contact the two second surfaces 22b.
[0036] In this configuration, the two first plate portions 42a sandwich the first shaft member 11 in the direction in which the hole 23 extends. The two second plate portions 42b sandwich the first shaft member 11 in a direction that intersects both the axial direction and the direction in which the hole 23 extends. Therefore, the cover 40 attached to the axial end of the first shaft member 11 is less likely to come off.
[0037] (3) A slit 24 is provided on the end face 21 of the first shaft member 11. The slit 24 extends from one second surface 22b to the other second surface 22b. The second plate portion 42b covers the slit 24.
[0038] With this configuration, the second plate portion 42b covers the slit 24, thereby suppressing the absorption or evaporation of moisture through the slit 24 of the first shaft member 11. Consequently, the expansion and contraction of the first shaft member 11 can be further suppressed.
[0039] (4) The end face 21 of the first shaft member 11 is provided with two slits 24. The end face 21 of the first shaft member 11 has two first end faces 21a, a second end face 21b, and two connecting surfaces 21c. The two first end faces 21a are located outside the two slits 24. The second end face 21b is located between the two slits 24. The second end face 21b is recessed relative to the first end face 21a. The connecting surface 21c is located between the first end face 21a and the second end face 21b. The first covering portion 41 has a first portion 41a that covers the first end face 21a, a third portion 41c that covers the second end face 21b, and a third portion 41c that covers the connecting surface 21c.
[0040] With this configuration, since the first covering portion 41 has a shape corresponding to the end face 21 of the first shaft member 11, the gap between the first covering portion 41 and the end face 21 becomes smaller. Therefore, the expansion and contraction of the first shaft member 11 can be further suppressed.
[0041] (5) The cover 40 is made of silicone rubber. According to this configuration, the adhesion of the cover 40 to the first shaft member 11 can be improved. (6) The first shaft member 11 is stored in a state where the cover 40 is attached to the axial end of the first shaft member 11. Thereby, the first shaft member 11 is stored in a state where the end face, which is a surface where moisture absorption or evaporation is likely to occur, is covered by the first covering portion 41 of the cover 40. Therefore, the absorption or evaporation of moisture from the end face of the first shaft member 11 can be suppressed. Also, the first shaft member 11 is stored in a state where the hole 23 is covered by the second covering portion 42 of the cover 40. Therefore, the absorption or evaporation of moisture through the hole 23 of the first shaft member 11 can be suppressed. Thus, the expansion and contraction of the first shaft member 11 can be suppressed. As a result, the displacement of the position of the hole 23 can be suppressed.
[0042] (7) Since the expansion and contraction of the first shaft member 11 are suppressed, the displacement of the position of the hole 23 is suppressed. Thereby, when the second plate 32 of the connecting metal fitting 13 is inserted into the slit 24 of the first shaft member 11, the plate hole 32a of the second plate 32 and the hole 23 of the first shaft member 11 are likely to overlap. Therefore, when connecting the first shaft member 11 and the connecting metal fitting 13 by inserting a drift pin 16 through the plate hole 32a and the hole 23, the first shaft member 11 is less likely to crack.
[0043] <Modification Example> The above-described embodiment is an example of a form that the expansion / contraction suppression jig 17 for a wooden shaft member and the protection method for a wooden shaft member can take, and is not intended to limit the form. The expansion / contraction suppression jig 17 for a wooden shaft member and the protection method for a wooden shaft member can take a form different from the form exemplified in the above-described embodiment. Examples thereof are forms in which a part of the configuration of the embodiment is replaced, changed, omitted, or a new configuration is added to the embodiment. Modification examples of the embodiment are shown below.
[0044] - The wooden shaft member is not limited to a wooden horizontal cross member extending in the horizontal direction. The wooden shaft member may be a wooden column extending in the vertical direction. - The cross-sectional shape of the first shaft member 11 is not limited to a square shape.
[0045] ・The number of holes 23 provided in the first shaft member 11 may be changed as appropriate. ・The direction in which the holes 23 extend does not have to be orthogonal to the axial direction of the first shaft member 11 as long as it intersects the axial direction of the first shaft member 11.
[0046] ・In the above embodiment, the drift pin 16 is inserted into the hole 23, but other connecting members such as bolts may be inserted. ・The hole 23 may open only in one of the two first surfaces 22a. In this case, the second covering portion 42 does not have to have two first plate portions 42a. The second covering portion 42 may have one first plate portion 42a that covers the hole 23.
[0047] ・The second covering portion 42 does not have to have two second plate portions 42b. Even in this case, the effect (1) of the above embodiment can be obtained. ・If the first covering portion 41 covers the end face of the first shaft member 11 so that the end face is not exposed, there may be a gap between the end face and the first covering portion 41.
[0048] ・The end face 21 of the first shaft member 11 does not have to be provided with the slit 24. ・The number of slits 24 provided in the end face 21 of the first shaft member 11 may be changed as appropriate. ・The end face 21 of the first shaft member 11 may be a flat surface. That is, the entire end face 21 may be an end face. In this case, the first covering portion 41 may be in a flat plate shape.
[0049] ・The cover 40 is not limited to being made of silicone rubber. The cover 40 may be made of metal, resin, rubber, or a composite material thereof. ・In the above embodiment, the second shaft member 12 to which the first shaft member 11 is connected is a horizontally extending cross member, but it may also be a column extending in the vertical direction.
[0050] ・In the above embodiment, the second shaft member 12 to which the first shaft member 11 is connected is made of wood, but it may also be made of steel. <Supplementary Note> This specification discloses the following technology.
[0051] [Note 1] A jig for suppressing expansion and contraction of a wooden shaft member, comprising a cover attached to the axial end of the wooden shaft member, wherein the axial end face of the wooden shaft member includes the end grain surface, the wooden shaft member is provided with a hole that extends in a direction intersecting the axial direction and opens on the outer circumferential surface of the wooden shaft member, and the cover comprises a first covering portion that covers the end grain surface and a second covering portion that covers the hole.
[0052] [Note 2] In the expansion and contraction suppression jig for the wooden shaft member described in Note 1, the cross-sectional shape of the wooden shaft member is square, the outer surface has two first surfaces that form a pair in the direction in which the hole extends, and two second surfaces that form a pair in a direction that intersects both the axial direction and the direction in which the hole extends, and the second covering portion has two first plate portions that contact the two first surfaces and two second plate portions that contact the two second surfaces.
[0053] [Note 3] In the wooden shaft member expansion and contraction suppression jig described in Note 2, a slit is provided on the end face, the slit extends from one of the second surfaces to the other of the second surfaces, and the second plate portion covers the slit.
[0054] [Note 4] In the wooden shaft member expansion and contraction suppression jig described in Note 3, the end face is provided with two slits, the end face has two first end faces as end faces located outside the two slits, a second end face as an end face located between the two slits and recessed relative to the first end faces, and a connecting surface located between the first end faces and the second end faces, and the first covering portion has a first portion that covers the first end faces, a second portion that covers the second end faces, and a third portion that covers the connecting surface.
[0055] [Note 5] Regarding the expansion and contraction suppression jig for the wooden shaft member described in Note 1, the cover is made of metal, resin, rubber, or a composite material thereof.
[0056] [Note 6] A method for protecting a wooden shaft member, wherein the wooden shaft member is stored with an expansion and contraction suppression jig for the wooden shaft member described in any one of Notes 1 to 5 attached to the axial end of the wooden shaft member.
[0057] 11...First shaft member as a wooden shaft member, 17...Expansion and contraction suppression jig, 21...End face, 21a...First end face as an end face, 21b...Second end face as an end face, 21c...Connecting surface, 22...Outer peripheral surface, 22a...First surface, 22b...Second surface, 23...Hole, 24...Slit, 40...Cover, 41...First covering part, 41a...First part, 41b...Second part, 41c...Third part, 42...Second covering part, 42a...First plate part, 42b...Second plate part.
Claims
1. A jig for suppressing expansion and contraction of a wooden shaft member, comprising a cover attached to the axial end of the wooden shaft member, wherein the axial end face of the wooden shaft member includes the end grain surface, the wooden shaft member is provided with a hole that extends in a direction intersecting the axial direction and opens on the outer circumferential surface of the wooden shaft member, and the cover comprises a first covering portion that covers the end grain surface and a second covering portion that covers the hole.
2. The expansion and contraction suppression jig for a wooden shaft member according to claim 1, wherein the cross-sectional shape of the wooden shaft member is square, the outer surface has two first surfaces that form a pair in the direction in which the hole extends, and two second surfaces that form a pair in a direction that intersects both the axial direction and the direction in which the hole extends, and the second covering portion has two first plate portions that contact the two first surfaces and two second plate portions that contact the two second surfaces.
3. The end face is provided with a slit, the slit extends from one of the second surfaces to the other of the second surfaces, and the second plate portion covers the slit, the expansion and contraction suppression jig for a wooden shaft member according to claim 2.
4. The end face is provided with two slits, the end face has two first end faces as end faces located outside the two slits, a second end face as an end face located between the two slits and recessed relative to the first end faces, and a connecting surface located between the first end faces and the second end faces, and the first covering portion has a first portion that covers the first end faces, a second portion that covers the second end faces, and a third portion that covers the connecting surface, the expansion and contraction suppression jig for a wooden shaft member according to claim 3.
5. The expansion and contraction suppression jig for a wooden shaft member according to any one of claims 1 to 4, wherein the cover is made of metal, resin, rubber, or a composite material thereof.
6. A method for protecting a wooden shaft member, wherein the wooden shaft member is stored with the expansion and contraction suppression jig for the wooden shaft member described in any one of claims 1 to 5 attached to the axial end of the wooden shaft member.