JPH0612084Y2 - Joining device for structural members - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a joining device for structural members, and more specifically, to a structural member such as a plurality of long steel pipes, which is easily and firmly attached to a node member at its tip. The present invention relates to a joining device.
This is used in the field of joints of structural members forming truss structures and the like.

[Conventional technology]

When many large structural members such as long steel pipes are used to construct a large three-dimensional structure, the truss structure is often formed by joining the tips of the structural members to the node members. A bolt or the like is used to join some structural members to one polyhedral nodal member. For example, Japanese Utility Model Publication No. 42-22992 proposes a joining device having such a structure, but has a drawback that it is difficult to sufficiently tighten the bolt when fixing the structural member to the node member. Further, in the joining device, there is a drawback that a sufficient torque cannot be applied due to a lack of cross section due to a notch or a hole. In addition, a part of the bolt screw portion, which is important in terms of proof strength, is exposed, so consideration for structural corrosion is lacking, and excessive strength and quality are required for the bolt, resulting in high cost. Incidentally, Japanese Patent Publication No. 56-29064 and the like describe a structure in which the joining bolt is covered with a sleeve-like one, and thereby the joining bolt is rotated. This is because there is a problem that the structural members cannot be resized because the joining bolts are attached to the end members that are integrated by welding or the like at the ends of the long structural main material.

By the way, the Applicant has a structure capable of strongly joining the structural member to the node member, avoiding the exposure of the joining bolt and making it resistant to corrosion, and having a simple and strong structure that is easy to dimension and has no cross-section loss. A joining device has been proposed in Japanese Patent Laid-Open No. 62-55347. As shown in FIG. 12, a joining bolt 6 for joining the structural member 2 to the nodal member 3 is provided with a boss portion 7 and screw portions 6a and 6b are formed on both sides thereof. It is composed of a structural main material 2A and an end member 2B. A female screw 9 having a diameter larger than the diameter of the anchor nut 8 screwed to the structural member side of the joining bolt 6 is formed inside the end member 2B integrated with the end of the structural main material 2A. The support member 11 screwed into the female screw 9 is formed with a sliding hole 12 for inserting and supporting the shaft portion 6m of the joining bolt 6, and engages with the outer surface of the boss portion 7 to rotate the joining bolt 6. There is a sleeve body 15 that transmits to the boss 7. The sleeve body 15 enables the axial displacement of the boss portion 7.

[Problems to be solved by the invention]

According to the above-mentioned joining device, the joining strength is high, the exposed state of the bolt is avoided in the joined state, and the dimensioning by machining is facilitated. However, due to its structure, the sleeve body 15 covers most of the joining bolt 6. On the other hand, when engaging the tip of the joining bolt 6 with the screw hole 5 of the node member 3, it is necessary for an operator to be able to visually recognize the tip of the joining bolt 6 or to feel the drop of the screw hole into the opening. is there. Therefore, in order to easily attract the tip of the joining bolt 6 into the screw hole 5 of the node member, the tip of the joining bolt 6 can be attracted at least from the tip of the sleeve body 15 as shown in FIG. 13 which is a state before joining. Only the length is projected. The amount of protrusion is short, for example, 3 to 5 mm, but as the space truss is assembled, the distance between the nodal members becomes the exact size, so that the protrusion of the joining bolt hinders the reasonable assembly. Therefore, it is necessary to carefully consider the order of assembling, or apply a force to the already-assembled portion with a hydraulic jack so that the space between the nodal members is slightly wider than the normal size for assembly. These operations are very time-consuming, and preparations for them are very cumbersome. On the other hand, the number of structural members used in one structure is very large, and it is inevitable that a structural member having a different size is incorporated. In that case, it is necessary to remove a structural member other than the predetermined one, but it is extremely difficult to remove one that has been assembled in a considerably assembled state.

In addition, in the joint bolt 6 and the sleeve body 15,
As described above, the sleeve body 15 engages with the outer surface of the boss portion 7 to transmit the rotation to the joining bolt 6, while the sleeve body 15
Can be displaced in the axial direction of the boss portion 7, but no consideration is given to connecting the joining bolt 6 and the sleeve body 15. Therefore, the structural member 2 is replaced by the nodal member 3.
When the posture of the structural member 2 is inclined or vertical in the work of attaching and detaching the sleeve body 15, the sleeve body 15 easily falls off from the joining bolt 6. As a result, there is a problem of hindering the efficiency of truss construction work.

The present invention has been made to solve the above problems,
Structural members can be installed or removed very easily and easily even when the size between the node members is becoming more accurate. Moreover, the structural members can be dimensioned easily and can be strongly joined to the node members, making the bolts less likely to corrode. It is an object of the present invention to provide a joining device which has a strong structure and can prevent the sleeve body from falling off when the structural member is incorporated in or removed from the node member or when the structural member is lifted in a truss construction work or the like.

[Means for solving problems]

The features of the joining device for structural members according to the present invention will be described with reference to FIG.

The end member 2B is integrated with the end of each structural main material 2A,
A joining bolt 6 for joining the structural main material 2A to the node member 3 in which the screw hole 5 is formed is provided via the end member 2B. The joining bolt 6 is provided with a boss portion 7 and threaded portions 6a and 6b are formed on both end portions thereof, and is screwed into the threaded portion 6a on the structural member side of the joining bolt 6 inside the end member 2B. A female screw 9 having a diameter larger than that of the anchor nut 8 to be formed is formed. A supporting member 11 that is screwed into the female screw 9 is fixed to the end member 2B, and a sliding hole 12 that inserts and supports the shaft portion 6m of the joining bolt 6 is provided at the center of the supporting member 11. In the vicinity of the boss portion 7, a conical coil spring 14 that intervenes the joining bolt toward the nodal point member via the boss portion by elastic force is interposed. A sleeve body 15 is provided that engages with the outer surface of the boss portion 7 and transmits rotation, while allowing the boss portion 7 to slide in the axial direction, and the end portion 14a of the conical coil spring 14 on the large diameter side is the sleeve body 15. Is engaged with the groove 17 formed on the inner surface of the, and the end portion 14b on the small diameter side is engaged with the joining bolt 6. Then, the conical coil spring is deformed so that the entire threaded portion 6b of the joining bolt 6 on the node member side can be retracted into the sleeve body 15 against the elastic force.

[Action]

The conical coil spring 14 has a large diameter end 14a engaged with a groove 17 formed in the inner surface of the sleeve body 15, and a small diameter end 14b engaged with the joining bolt 6. There is. Therefore, the sleeve body 15 and the conical coil spring 14
As a result, the sleeve body 15 does not fall off from the joining bolt 6.

In the truss construction work, the joint bolt 6 is pushed into the sleeve body 15 against the conical coil spring 14 and is arranged between the two node members 3 and 3 which are out of size. The joining bolt 6 is in the sleeve body 15 until the tip of the joining bolt 6 coincides with the screw hole 5 of the node member 3, but when the tip of the joining bolt 6 faces the screw hole 5 of the node member 3, the joining bolt 6 becomes conical coil spring 14. The elastic force causes the protrusion, and the tip is called into the screw hole 5. The sleeve body 15 is rotated, the joining bolt 6 is rotated through the boss portion 7, and the screw portion 6b is advanced into the screw hole 5 of the node member 3. Although the outer surface of the boss portion 7 is in engagement with the sleeve body 15, sliding displacement is possible in the axial direction, and the engagement of the joining bolt 6 is not hindered. When the joining bolt 6 advances by a predetermined distance, the anchor nut 8 screwed into the joining bolt 6 contacts the support member 11.

On the other hand, when removing the structural member 2 assembled between the node members 3, the sleeve body 15 is rotated in the opposite direction. The joining bolt 6 retracts against the conical coil spring 14, and the tip of the joining bolt 6 is returned to the opening position of the screw hole 5. The joining bolt 6 is urged by the conical coil spring 14 toward the nodal member 3, but the tip of the threaded portion 6b and the opening of the screw hole 5 are chamfered, and the sleeve bolt 15 can be displaced laterally. 6 further retracts against the conical coil spring 14. Therefore, the structural member 2 located between the node members 3 having the exact size is also
Very easy to remove.

[Effect of device]

According to the present invention, it is possible to dispose a structural member, which has been accurately dimensioned by machining, between two node members that are exactly dimensioned. Then, the operation for drawing the joining bolt into the screw hole of the node member can be easily performed by expanding and contracting the conical coil spring. In order to tighten the joining bolt, a large torque can be applied to the sleeve body to firmly fix it to the node member. In the joined state, the sleeve body is interposed between the end member and the nodal member to prevent the joining bolt from being exposed and to prevent corrosion of the bolt screw portion, which is important in terms of yield strength.

Furthermore, since the sleeve body is always connected to the joint bolt via the conical coil spring, it is possible to prevent the sleeve body from falling off when the structural member is assembled into or removed from the nodal member, or when it is lifted to a high place. The truss construction work can be facilitated.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings showing an embodiment thereof.

FIG. 1 is an overall cross-sectional view including a joining device 1, in which the tip end of a structural member 2 is joined to a node member 3 in a radial manner (a cross in this example). The structural member 2 is composed of a structural main material 2A in which a long steel pipe or the like is adopted and an end member 2B, and a thick plate-shaped end member 2B is integrated with an end of the structural main material 2A by welding or the like. A joining bolt 6 for joining the structural main material 2A to the node member 3 in which the screw hole 5 is formed is provided via the end member 2B. The structural member 2 is
The total length including the end members 2B at both ends integrated with it must be accurate, and even if other parts may be assembled to the end member 2B afterwards by screwing, etc. Since there are no integrated parts, the end member 2B
The length from the end face 2n to the other end face is accurately dimensioned by machining in the factory.

The joining bolt 6 is provided with a boss portion 7, and
The threaded portions 6a and 6b at both end portions thereof are formed in reverse threads. The screw portion 6b formed on the node member 3 side with the boss portion 7 as a boundary is, for example, a right screw, and when the structural member 2 is attached to the node member 3, the anchor nut 8 attached to the structural member side is the joining bolt 6 The threaded portion 6a has a left-hand thread so that it does not come off in the structural member 2 due to the rotation. When the screw parts 6a and 6b are screws in the same direction, a screw lock agent may be applied to the screw part 6a to secure the screw engagement with the anchor nut 8.

A female screw 9 having a diameter larger than the diameter of the anchor nut 8 screwed to the structural member side of the joining bolt 6 is formed inside the end member 2B. Female thread 9 of the end member 2B
A support member 11 on which a male screw 10, which should be called a sleeve nut, is formed, is screwed on, and an adhesive material such as a screw locking agent is applied to the screw portion to prevent loosening. At the center of the support member 11, the shaft portion 6m of the joining bolt 6 is
A slide hole 12 for inserting and supporting the slide hole is provided. The support member 11 does not have to be completely housed in the end member 2B, and may support the joining bolt 6 as shown in the drawing and not hinder the rotation of the sleeve body 15 described later. In this example, the amount of screwing is adjusted at the time of assembly so that the tip of the support member 11 projects from the end member 2B by the length L shown in FIG. 3, and corrosion of the joining bolt 6 is reduced as described later. Consideration has been given to enhance the sealing performance.

The joining bolt 6 is previously provided in the sliding hole 12 of the support member 11.
After the shaft portion 6m is inserted [see FIG. 5] and the anchor nut 8 is attached to the screw portion 6a, the support member 11 is screwed into the female screw 9 of the end member, and the joining device 1 is attached to the structural member 2. It is attached. A conical coil spring 14 is interposed between the support member 11 and the boss portion 7 of the joining bolt 6. A sleeve body 15 that engages with the outer surface of the boss portion 7 and transmits rotation is provided outside the joining bolt 6. For example, it is a hexagonal tubular body that fits into the boss portion 7 formed in a hexagonal shape, and the inside thereof allows the boss portion 7 to slide in the axial direction. A rotational force acting portion 16 for rotating the boss portion 7 is formed on the outer surface of the sleeve body 15, and can be rotated by, for example, applying a spanner or the like.

The large-diameter side end 14a of the conical coil spring 14 is fitted into and engaged with the groove 17 [see FIG. 2] formed in the structural member side of the sleeve body 15, while the small-diameter side end thereof is engaged. Part 14b
Is in a position close to the boss 7 and is in an engaged state in which the shaft abuts on the boss 7 or is wound around the shaft 6m near the boss 7. That is, the presence of the anchor nut 8 prevents the joining bolt 6 from coming off from the end member 2B, and prevents the sleeve body 15 from coming off while the conical coil spring 14 is engaged as if it is in contact with the boss portion 7. ing. In FIG. 1, the boss portion 7 largely advances toward the nodal point member 3 and the conical coil spring 14 is in the extended free state or a state close thereto, but before the joining to the nodal point member 3, the conical coil spring 14 is The elastic force of 14 urges the boss portion 7 toward the node member 3. As shown in FIG. 2, for example, a quarter arc of the end portion 14a of the conical coil spring 14 is fitted in the groove 17, but as shown by the alternate long and short dash line, an annular shape is formed along the inner peripheral surface of the sleeve body 15. It is considered as a groove.

The sleeve body 15 permanently covers the joining bolt 6 in the latter half of the assembly of the structural member 2 to the nodal member 3, but in order to improve the function of preventing the contact between the joining bolt 6 and the outside air and the adhesion of moisture, this example is used. However, the seal structure shown in FIG. 3 is adopted between the sleeve body 15 and the end member 2B and between the sleeve body 15 and the node member 3. That is, the sleeve body 15
A step portion 15n into which the tip of the support member 11 is fitted is formed at the inner end portion of the end member 2B side, and when the end surface 15a of the sleeve body 15 contacts the end surface 2n of the end member 2B,
The end surface of the support member 11 is also the stepped concave surface 15b of the sleeve body 15.
The size of the stepped portion and the above-described screwing amount of the support member 11 are adjusted so that the contact surface comes into contact with, and the polymer absorbent 4 or the like is thinly applied to the contact surface. When the polymer absorbent 4 expands due to moisture, extremely high watertightness can be obtained. When the sleeve member 15 is rotated to fix the structural member 2 to the nodal member 3, the fastening force from the nodal member 3 is transmitted to the structural member 2 side through the contact surfaces at the two positions.

On the other hand, when the elastic packing 19 is attached to the screw portion 6b side of the boss portion 7 and the thickness of the packing is largely selected, when the joining bolt 6 is engaged with the screw hole 5 of the node member 3 by the rotation of the sleeve body 15. Elastic packing 19 is boss 7
And the watertightness is achieved even on the node member 3 side. In this way, since the both ends of the sleeve body 15 are sealed, infiltration of water liquid or outside air into the sleeve body 15 is avoided, and the joining device 1 that can withstand long-term use can be obtained.

According to the embodiment having such a configuration, the joining device 1 is formed as follows to strengthen the joining of the structural member 2 and the nodal member 3 and prevent the sleeve body 15 from falling off from the joining bolt 6. Can be prevented.

First, the end members 2B are integrated with both ends of the structural main material 2A cut into a predetermined size by welding or the like. At that time, since the welding distortion occurs, the dimension of the structural member 2 is distorted. However, a predetermined dimension can be obtained by machining the end surface 2n of the end member 2B. The female screw 9 of the end member 2B is in a relatively large open state, and the end member 2B
Surface treatments for rust prevention on the inner and outer surfaces of the structural member 2 including, for example, pickling, bondage treatment of coating film base, baking coating, hot dip galvanizing, etc. can be easily performed.

Next, as shown in FIG. 4, the end portion 14 b of the conical coil spring 14 on the small diameter side is fitted onto the shaft portion 6 m from the structural member side of the joining bolt 6 so as to be close to the boss portion 7. When the joining bolt 6 in that state is pushed into the sleeve body 15 from the large diameter side of the conical coil spring 16, the movement of the conical coil spring 14 is restricted by the boss portion 7 and the conical coil spring 14 is accommodated in the sleeve body 15 while being slightly deformed. When the end portion 14a on the large diameter side is fitted into the groove 17 and the diameter thereof is slightly expanded, the engagement state with the sleeve body 15 is obtained. At this time, the inner surface of the sleeve body 15 is engaged with the boss portion 7,
The sleeve body 15 and the joining bolt 6 can be integrally rotated. When the support member 11 is fitted on the shaft portion 6m and the anchor nut 8 is screwed into the screw portion 6a as shown in FIG. 5, the sleeve body 15 does not come out to the support member 11 side, but to the boss portion 7 side. Does not come off unless a force large enough to disengage the conical coil spring 14 from the groove 17 acts, and the integrated state of the sleeve body 15 and the joining bolt 6 is maintained. In addition, the temporary fixing nut 13 is screwed into the threaded portion 6b protruding from the end of the sleeve body 15, and the stepped concave surface 1
The frictional force between 5b (see FIG. 3) and the tip of the support member 11 is strengthened. Then, it is inserted into the opening of the end member 2B from the anchor nut 8 side, and as shown in FIG. 6, the male screw 10 of the support member 11 is screwed into the female screw 9 of the end member 2B, and the rotational force acting portion of the sleeve body 15 is engaged. Put a spanner on 16 and screw in. When fixing the support member 11 to the end member 2B, the screwing amount is determined so as to project from the end surface 2n of the end member 2B by a predetermined length L [see FIG. 3], and the screw locking agent applied in advance is used. The integration is aimed at. After that, the temporary fixing nut 13 is removed, and the joining device 1 is moved to the position of the node member 3 together with the structural member 2 as shown in FIG.

As shown in FIG. 8, the tip 6n of the threaded portion 6b of the joining bolt 6 is pushed in by using the spherical surface 3a of the nodal member 3, and the joining bolt 6 is completely resisted against the conical coil spring 14 as shown in FIG. Then, it is retracted into the sleeve body 15. Joining bolt 6
The joining bolt 6 is in the sleeve body 15 until the tip 6n of the contact point is aligned with the screw hole 5 of the node member 3, but when the tip 6n faces the screw hole 5 of the node member 3, the joining bolt 6 is elastically attached to the conical coil spring 14. The protrusion 6n is generated by the force, and the tip 6n is called into the opening of the screw hole 5 as shown in FIG.

Rotation is applied by using the rotational force acting portion 16 formed on the outer surface of the sleeve body 15, and the joining bolt 6 is rotated through the boss portion 7. The screw portion 6b advances into the screw hole 5 of the node member 3, but at that time, the outer surface of the boss portion 7 can be slidably displaced in the axial direction, and the joining bolt 6 is engaged with the node member 3 as shown in FIG. It The shaft portion 6m of the joining bolt 6 also slides in the sliding hole 12 of the support member 11, and when the joining bolt 6 advances a predetermined distance, the anchor nut 8 screwed into the joining bolt 6 comes into contact with the support member 11. The distance 1 between the anchor nut 8 screwed to the structural member side of the joining bolt 6 and the support member 11 is
As shown in FIG. 9, since the distance between the boss portion 7 and the end surface of the sleeve body 15 is set to be shorter than 2, a predetermined torque can be applied to the joining bolt 6 via the sleeve body 15. At this time, the threaded portion 6a of the anchor nut 8 and the threaded portion 6b of the anchor member 3 are reverse threads to each other. The engagement with the threaded portion 6a is promoted, and the anchor nut 8 is prevented from coming off the threaded portion 6a, and the joining bolt 6 is prevented from further advancing.

The fastening force for attaching the joining bolt 6 to the node member 3 is transmitted to the end member 2B via the sleeve body 15 and the support member 11, and is received by the structural main member 2A. The transmission of the force at that time is performed through the end surface 15a of the sleeve body 15 (see FIG. 3) and the stepped concave surface 15b, and the contact surface is sealed as described above. The elastic packing 19 attached to the screw portion 6b of the boss portion 7 is sandwiched between the sleeve body 15, the boss portion 7 and the node member 3 and compressed, so that the left and right end portions of the sleeve body 15 are made watertight. In such a joined state, the sleeve body 15 is interposed between the end member 2B and the nodal member 3, and especially when used as a ceiling beam in a building of a plating plant or the like. It is possible to prevent the steam of the above from touching the joining bolt 6.

On the other hand, if it is found that the structural member 2 is mistakenly incorporated,
It must be removed in order to replace it with the required structural member. In that case, the sleeve body 15 is rotated in the opposite direction. The joining bolt 6 retracts against the conical coil spring 14, and the tip 6n thereof is returned to the opening position of the screw hole 5 as shown in FIG. The joint bolt 6 is a conical coil spring 14
Is urged toward the nodal member 3 by
The tip 6n of b and the opening of the screw hole 5 are chamfered. When the sleeve body 15 is laterally displaced, the joining bolt 6 is further retracted against the conical coil spring 14 as shown in FIG. Therefore, the structural member 2 located between the node members 3 of the exact size can be removed very easily.

The conical coil spring 14 shown in FIG. 1 of the above embodiment is
Although it is interposed between the support member 11 and the boss portion 7,
Also in the example as shown in FIG. 1, the sleeve body 15 is connected to the joining bolt 6 by the conical coil spring 14 and does not fall off. That is, the end portion 4b on the small diameter side of the conical coil spring 14 is wound around and engaged with the screw portion 6b in the vicinity of the boss portion 7, while the end portion 14a on the large diameter side is located at the tip end position of the inner surface of the sleeve body 15. It is fitted into and engaged with the groove 17 formed in the groove. In the state shown in FIG. 11, the conical coil spring 14 is in a contracted free state or a state close thereto, and when the screw portion 6b is retracted into the sleeve body 15, it is extended to urge the joining bolt 6 toward the screw hole 5 direction. It is supposed to do.

As described in detail above, according to such a joining device, a large torque can be easily applied by using the rotational force acting portion of the sleeve body to tighten the joining bolt. Even if the structural members are assembled one after another and the distance between the nodal members becomes even, the conical coil spring can be used to easily attach and detach the connecting bolt from the sleeve body. In addition, the structural member 2 integrated with the joining bolt 6
Even when the structure member 2 is lifted to a high place or when the structural member 2 is assembled or removed from the nodal member 3, the sleeve body 15 does not easily fall off from the joining bolt 6 even if the posture thereof is oblique or vertical. In this way, in the work of constructing the truss structure, the sleeve body 15 is prevented from falling off, and it is necessary to consider the order of assembling the structural members and forcibly widen the distance between the nodal members to assemble them as in the conventional case. Can be done very efficiently. Then, the joining device is not damaged or unnecessary stress does not act, so that the stress state as designed can be realized and a highly reliable structural member can be obtained. Further, in the jointed state, the jointed bolt is prevented from being exposed, and the sealing property is improved by a polymer absorbent material or the like, so that corrosion of the bolt screw portion, which is important in terms of proof stress, is suppressed. Complete internal watertightness, which was not possible with the conventional bolt assembly type joining device, is realized, and it can be sufficiently applied to outdoor structures. Further, the structural member has a configuration that allows easy dimensioning by machining, and surface treatment is also easy.
In addition, the joining bolt does not accompany the surface treatment of the structural member, and it is possible to avoid a decrease in bolt strength due to plating,
It is also possible to use high strength bolts that can not be plated,
It has many practically excellent effects.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a welding apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, FIG. 3 is an enlarged view of the welding apparatus, and FIGS. 10 is a sectional view for explaining the operation, FIG. 11 is a longitudinal sectional view of a joining apparatus in a different embodiment, FIG. 12 is a sectional view of a joining apparatus in the prior art,
FIG. 13 is a sectional view showing a state in which the tip of the joining bolt is projected from the sleeve body. 2 ... Structural member, 2A ... Structural main material, 2B ... End member, 3 ... Nodal member, 5 ... Screw hole, 6 ... Joint bolt, 6a, 6b ... Screw part, 6m ... Shaft part , 7 ... Boss part, 8 ... Anchor nut, 9 ... Female screw, 11 ... Support member, 12 ... Sliding hole, 14 ... Conical coil spring, 1
4a, 14b ... End, 15 ... Sleeve body, 17 ...
groove.

Claims (1)

[Scope of utility model registration request] 1. An end member is integrated with an end portion of each structural main material, and a connecting bolt for connecting the structural main material to a node member having a screw hole is provided through the end member. The joining bolt is provided with a boss portion, and threaded portions are formed at both end portions thereof, and inside the end member, the diameter is larger than the anchor nut diameter screwed into the threaded portion on the structural member side of the joining bolt. A female screw having a diameter is formed, a supporting member screwed into the female screw is fixed to the end member, and a sliding hole for inserting and supporting the shaft portion of the joining bolt is provided in the center portion of the supporting member. In the vicinity of the boss portion, a conical coil spring that urges the joining bolt toward the node member through the boss portion by elastic force is interposed, and engages with the outer surface of the boss portion to transmit rotation. Allows axial sliding of boss A sleeve body is provided, the large diameter side end of the conical coil spring is engaged with a groove formed in the inner surface of the sleeve body, and the small diameter side end is engaged with a joining bolt, The conical coil spring is adapted to be deformed so as to withdraw all of the threaded portion of the joining bolt on the side of the nodal point member into the sleeve body against the elastic force thereof. Equipment for joining structural members.