JP7409796B2 - Joining structure of members, joining method, temporary structure, and assembly and disassembly method of temporary structure - Google Patents

Description

The present invention relates to, for example, a joining structure and a joining method for members constituting a temporary structure, a temporary structure, and a method for assembling and disassembling the temporary structure.

2. Description of the Related Art Conventionally, as a temporary structure used at a construction work site, a framework scaffold made of members such as single steel pipes assembled with metal fittings and the like has been known (see, for example, Patent Documents 1 and 2). Dry bolts and pins are used to join parts, giving priority to efficiency in assembly and disassembly. In this connection, the shear force is expected to be the bearing force of bolts and pins, so there is a risk of looseness or play due to the accuracy of processing and assembly of the materials. Temporary structures as a whole are piled up, causing unexpected deflection and deformation, which often causes delays in construction schedules.

Japanese Patent Application Publication No. 2016-217058 JP2017-089269A

For this reason, there has been a need to eliminate looseness at joints between members such as single pipes.

The present invention has been made in view of the above, and an object of the present invention is to provide a joining structure and a joining method for members without backlash, a temporary structure, and a method for assembling and disassembling the temporary structure.

In order to solve the above-mentioned problems and achieve the objects, a member joining structure according to the present invention is a structure for joining members together, and is arranged so as to be engaged with the ends of both members. It is characterized by comprising a joint part to be connected, and a thermoplastic adhesive provided in a gap between the joint part and the end of the member to bond the joint part and the member.

Further, another member joining structure according to the present invention is characterized in that, in the above-mentioned invention, the adhesive material is a sheet-like thermoplastic resin.

Further, the method for joining members according to the present invention is a method for joining members together, and includes a step of engaging and arranging joint parts at the ends of both members to connect both members, and a step of connecting the joint parts and the member. The method is characterized by comprising a step of providing a thermoplastic adhesive in the gap between the end portion of the joint component and the member, and a step of heating the thermoplastic adhesive provided in the gap to bond the joint component and the member.

Further, another method of joining members according to the present invention is characterized in that the adhesive material is a sheet-like thermoplastic resin in the above-described invention.

Moreover, the temporary structure according to the present invention is characterized by having the above-described member joining structure.

Furthermore, the method for assembling and dismantling a temporary structure according to the present invention is a method for assembling or dismantling the above-mentioned temporary structure, which includes the steps of joining members together using the above-mentioned member joining method during assembly, and during disassembly. The present invention is characterized by comprising at least one of the steps of separating the joint component and the member by heating a thermoplastic adhesive provided in the gap.

According to the member joining structure according to the present invention, the member is joined to each other, and the joint part is arranged to engage with the ends of both members and connects both the members, and the joint part and the end of the member Since the thermoplastic adhesive is provided in the gap between the joint parts and the members, it is possible to provide a joining structure of the members without looseness.

Further, according to the joining structure for other members according to the present invention, since the adhesive is a sheet-shaped thermoplastic resin, the adhesive can be easily provided in the gap between the joint component and the member. play.

Further, according to the method for joining members according to the present invention, the method includes the steps of: arranging joint parts in engagement with the ends of both members to connect both members; The method includes a step of applying a thermoplastic adhesive in the gap between the joint part and the end of the member, and a step of heating the thermoplastic adhesive provided in the gap to bond the joint part and the member. This has the advantage that it is possible to provide a method for joining members that do not have the same structure.

Furthermore, according to the method for joining other members according to the present invention, since the adhesive is a sheet-shaped thermoplastic resin, the adhesive can be easily provided in the gap between the joint component and the member. play.

Furthermore, since the temporary structure according to the present invention includes the above-described member joining structure, it is possible to provide a temporary structure that suppresses unexpected deflection and deformation due to backlash.

Furthermore, according to the method for assembling and dismantling a temporary structure according to the present invention, there is provided a method for assembling or dismantling the above-mentioned temporary structure, which includes the step of joining members together using the above-mentioned member joining method during assembly; During disassembly, the temporary structure can be assembled and dismantled easily and quickly because it includes at least one step of separating the joint parts and members by heating the thermoplastic adhesive provided in the gap. be effective.

FIG. 1 is a diagram showing an embodiment of a member joining structure, a joining method, a temporary structure, and a method for assembling and dismantling a temporary structure according to the present invention, (1) is a linear joint, (2) to (4) ) is the joining procedure. FIG. 2 is an explanatory diagram of a test to verify the effects of the present invention. FIG. 3 is a photographic diagram showing the bending test situation. FIG. 4 is a diagram showing the relationship between the bending load and the displacement of the applied point. FIG. 5 is a photographic diagram showing a straight joint and a single pipe separated after a bending test.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a member joining structure, a joining method, a temporary structure, and a method for assembling and disassembling a temporary structure according to the present invention will be described in detail below with reference to the drawings. Note that the present invention is not limited to this embodiment.

As shown in FIG. 1 (4), the member joining structure according to the embodiment of the present invention is a structure in which steel single pipes 12, 12 (members) are joined in series, and both single pipes 12, 12 (members) are joined in series. A steel linear joint 14 (joint part) that is inserted into the ends of the pipes 12, 12 and connects the two, and a gap between the outer periphery of the linear joint 14 and the inner periphery of the end of the single pipe 12. It is provided with a thermoplastic adhesive 16 for bonding the linear joint 14 and the single pipe 12.

As shown in FIG. 1(1), the linear joint 14 is composed of a cylindrical member in which a central annular large diameter portion 18 and both side small diameter portions 20 are integrally connected in a concentric manner. The small diameter portion 20 extends on both sides of the large diameter portion 18, and has a pair of L-shaped grooves 22 formed at its open end. As shown in FIG. 1(2), the small diameter portion 20 can be inserted into the open end of the single pipe 12.

The adhesive material 16 is made of thermoplastic resin molded into a sheet shape, and is arranged in advance by wrapping it around the outer peripheral surface of the small diameter portion 20 of the linear joint 14 . By attaching the adhesive 16 in the form of a sheet to the linear joint 14 in advance, the adhesive 16 can be easily inserted into the gap between the linear joint 14 and the single pipe 12. Although the adhesive 16 of this embodiment is not placed on the open end side including the L-shaped groove 22 portion, it may be placed on the open end side excluding the L-shaped groove 22 portion. The adhesive 16 may be, for example, a hot melt adhesive that is solid at room temperature, liquefies by heating and melting, applies to the adherend, and forms a bond by cooling and solidifying. Furthermore, polyolefin thermoplastic resins used for adhesion of automobile interior materials and home appliance parts may also be used. The adhesive material 16 is not limited to a sheet form, and may be of any type as long as it can be filled into the gap between the linear joint 14 and the single pipe 12; Preferably.

As shown in FIG. 1(2), a locking pin 24 that penetrates the single pipe 12 in the diameter direction is fixed to the single pipe 12. This pin 24 is for preventing rotation, and can be locked in the L-shaped groove 22 of the linear joint 14.

Next, a method for joining members according to this embodiment will be explained.
First, a sheet-like adhesive 16 is wrapped around the small diameter portions 20 on both sides of the linear joint 14. Next, one small diameter portion 20 of the linear joint 14 is inserted into the open end of the single pipe 12. Next, when the linear joint 14 is rotated in the direction of the arrow with the pin 24 inserted into the L-shaped groove 22, the pin 24 is locked in the L-shaped groove 22, and as shown in FIG. 1(3), the linear joint 14 is rotated in the direction of the arrow. 14 is connected to the single pipe 12 and locked. As a result, the sheet-like adhesive 16 is placed in the gap between the outer peripheral surface of the small diameter portion 20 and the inner peripheral surface of the single pipe 12. Next, as shown in FIG. 1(4), the small diameter portion 20 on the opposite side is inserted into the open end of the single pipe 12, the pin 24 is inserted into the L-shaped groove 22, and the single pipe 12 is moved in the direction of the arrow. When rotated, the linear joint 14 is connected to the single pipe 12 via the pin 24 and the L-shaped groove 22 and locked. As a result, the sheet-like adhesive 16 is placed in the gap between the outer peripheral surface of the small diameter portion 20 and the inner peripheral surface of the single pipe 12.

Subsequently, the portion of the linear joint 14 is heated to a temperature higher than the softening point of the thermoplastic resin of the adhesive 16 to blend the resin. As the resin conforms to the shape of the gap, the inner circumferential surface of the single pipe 12 and the outer circumferential surface of the linear joint 14 are bonded together, and the gap between the two is filled with the resin, resulting in a joint structure of the single pipe 12 without play. is obtained. In this way, by sequentially connecting the single pipes 12 and the linear joints 14, a large number of single pipes 12 can be connected in series. This makes it possible to assemble a temporary structure such as a single-tube scaffolding having a horizontal handrail or the like extending over the entire length of the scaffolding.

Since the joint structure of this embodiment has no play, it is possible to reduce unexpected bending or deformation of a temporary structure such as a single-tube scaffold assembled using this joint structure. Furthermore, by heating the linear joint 14 during disassembly of the temporary structure, the adhesive force between the inner circumferential surface of the single pipe 12 and the outer circumferential surface of the linear joint 14 is weakened by the thermoplasticity of the adhesive 16. Thereby, the bonded linear joint 14 and single pipe 12 can be easily and quickly separated. Therefore, the temporary structure using the joint structure of this embodiment can be easily and quickly assembled and dismantled. The separated straight joint 14 and single pipe 12 can be reused.

(Verification of effects of the present invention)
In order to verify the effects of the present invention, two single pipes (diameter 48.3 mm, thickness 2.4 mm, length 300 mm) were joined using a commercially available linear joint, and a four-point bending test was conducted. Figure 2 (1) shows the dimensions of the linear joint, (2) and (3) the procedure for forming the test specimen, and (4) the test equipment.

In the straight joint of the embodiment of the present invention, a thermoplastic resin (polyolefin hot melt adhesive "Evergrip (registered trademark) AS852") molded into a sheet for the inserted part (φ41.9 mm) of the straight joint, (manufactured by Toagosei Co., Ltd.) was wound to a width of 60 mm and inserted into a single pipe by pushing it in with some force. When the part where the straight joint was inserted was evenly heated with an 1800W industrial hair dryer, softened thermoplastic resin could be seen seeping out from the gap between the straight joint and the end of the single pipe after about 5 minutes. After heating for an additional 3 minutes, it was cooled to room temperature. After the temperature had cooled down and the resin had hardened, no play or play was observed in the straight joint.

The four-point bending test was conducted under conditions in which the distance between supporting points was 500 mm and the distance between applying points was 300 mm, as shown in FIGS. 2(4) and 3. The number of test specimens was two using thermoplastic resin (Examples 1 and 2), one without thermoplastic resin for comparison (Comparative Example 1), and a single pipe without a straight joint (for comparison). Example 2) is one body each. Note that the joint part was placed in the pure bending section.

Figure 4 shows the relationship between the bending load and the average displacement of the applied point. The displacement at the load (35.9 kN) at which the single pipe bends and yields is 9.6 mm for the single pipe (Comparative Example 2) and 11.4 mm for the linear joint bonded with thermoplastic resin (Examples 1 and 2). and 11.2 mm, and the dry type linear joint (Comparative Example 1) was 14.0 mm. It was confirmed that the linear joints using the thermoplastic resin of Examples 1 and 2 are effective in suppressing the deflection of the linear joints in the stress range to the extent that a single pipe yields in bending.

One side of the test specimens (Examples 1 and 2) after the four-point bending test was held in a vise, and force was applied while heating the joint part with an industrial dryer. Approximately 3 minutes after heating started, the single pipe began to move in the circumferential direction, and 5 minutes later it was able to be removed from the linear joint. Figure 5 shows the situation after removing it.

The thermoplastic resin (AS852) used in the above test is a heat-resistant resin with a softening point of 150°C and a hot melt usage temperature of 200°C to 220°C, and is suitable for adhesion of automobile interior materials and home appliance parts. It is widely used in Polyolefin resins exhibit good adhesion to a variety of materials, and in general specifications, some resins have a lower softening point than AS852 (more than 100°C, operating temperature 150°C to 180°C). be. Since even better adhesive bonding and separation properties can be expected in areas where heat resistance is not required, these resins are used as adhesives for joining single pipes included in temporary structures such as single pipe scaffolding. Good too.

Furthermore, by setting the width of the sheet-like thermoplastic resin to 60 mm or more, the bending strength of the linear joint can be exhibited that is higher than the bending yield strength of the base material (single pipe). In the straight joints of single pipes tested, no backlash occurred even in the stress range where the base material (single pipe) yielded in bending, stress transmission was smooth, and the joints had improved rigidity. The bonded joints can be separated by reheating, and the ``ease of disassembly'' of the temporary members is not significantly impaired. Furthermore, the separated members can be reused.

As explained above, the member joining structure according to the present invention is a structure for joining members together, and includes a joint part that is engaged with the ends of both members and connects both members, and a joint part that connects both members. Since the thermoplastic adhesive is provided in the gap between the parts and the ends of the members and adheres the joint parts and the members, it is possible to provide a joint structure of the members without backlash.

Further, according to the joining structure for other members according to the present invention, since the adhesive is a sheet-shaped thermoplastic resin, the adhesive can be easily provided in the gap between the joint component and the member.

Further, according to the method for joining members according to the present invention, the method includes the steps of: arranging joint parts in engagement with the ends of both members to connect both members; The method includes a step of applying a thermoplastic adhesive in the gap between the joint part and the end of the member, and a step of heating the thermoplastic adhesive provided in the gap to bond the joint part and the member. It is possible to provide a method for joining members that do not have the same structure.

Further, according to the method for joining other members according to the present invention, since the adhesive is a sheet-shaped thermoplastic resin, the adhesive can be easily provided in the gap between the joint component and the member.

Furthermore, since the temporary structure according to the present invention includes the above-described member joining structure, it is possible to provide a temporary structure that suppresses unexpected bending and deformation due to backlash.

Furthermore, according to the method for assembling and disassembling a temporary structure according to the present invention, there is provided a method for assembling or disassembling the above-mentioned temporary structure, which includes the step of joining members together using the above-mentioned member joining method during assembly; At the time of disassembly, at least one of the steps of separating the joint parts and members by heating the thermoplastic adhesive provided in the gap is provided, so that the temporary structure can be assembled and dismantled easily and quickly.

As described above, the member joining structure, joining method, temporary structure, and method for assembling and dismantling temporary structures according to the present invention are useful for temporary structures such as frame scaffolds made of single pipes used at construction sites. It is particularly suitable for reducing unexpected looseness or deformation that occurs in temporary structures.

12 Single pipe (member)
14 Straight joint (joint parts)
16 Adhesive 18 Large diameter portion 20 Small diameter portion 22 L-shaped groove 24 Pin

Claims (4)

A structure in which single steel pipes are connected in series ,
A linear joint made of steel that is arranged to engage with the ends of both of the single pipes and connects both of the single pipes , and provided in a gap between the straight joint and the end of the single pipe , A member joining structure comprising a thermoplastic adhesive for bonding the linear joint and the single pipe , the adhesive being a sheet-like thermoplastic resin . A method of joining single steel pipes in series ,
connecting both of the single pipes by engaging and arranging a steel straight joint at the ends of both of the single pipes ; providing a thermoplastic adhesive, and heating the thermoplastic adhesive provided in the gap to bond the straight joint and the single pipe , the adhesive being a sheet-like heat-resistant adhesive. A method for joining members characterized in that they are made of plastic resin . A temporary structure comprising the member joining structure according to claim 1 . A method for assembling or dismantling the temporary structure according to claim 3 ,
At the time of assembly, the step of joining the single pipes by the member joining method according to claim 2 , and at the time of disassembly, heating the thermoplastic adhesive provided in the gap to connect the straight joint and the single pipe. A method for assembling and dismantling a temporary structure, comprising at least one step of separating the structure from the pipe .

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