JP2007319868A - Stud, ferrule, and welding method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adequately perform stud welding of a special shaped stud without any pre-treatment such as cutting off a projection of the special shaped stud having a projection on the outer circumference of a bar steel. <P>SOLUTION: A welding ferrule 10 has a cylindrical shape on the whole with both ends thereof in the axial direction opened, and comprises a ferrule body 20 having a stud insertion hole 21 on one end side in the axial direction and having an internal space 22 to be continued to the hole 21 on the other end side in the axial direction, and an easily deformable and non-combustible shield part 30 extending in a flange shape inward of the hole 21. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stud and a ferrule used for stud welding, and a stud welding method using them.

  The configuration of a stud welding device for performing stud welding is disclosed in, for example, Patent Document 1, and welding using such a stud welding device is generally performed as follows.

  A predetermined stud is held at the proximal end of the distal end chuck of the welding apparatus. An operator holding the main body housing presses the ferrule externally fitted to the tip of the stud against the base material by using a ferrule pressing guide attached to the main body housing. Since the ferrule is externally fitted so as to be axially movable relative to the stud, at this time, the stud has a shape in which the tip is pressed against the base material by the elastic force of the spring that urges the driving main shaft in the pushing direction. Become. When the start switch arranged at an appropriate part of the main body housing is pressed while this state is maintained, the drive main shaft or stud is pulled up by a predetermined distance by electromagnetic force, and a predetermined clearance is provided between the tip of the stud and the base material. it can. Next, a welding current is supplied from the power supply cable. An arc discharge occurs between the tip of the stud and the base material, and the tip of the stud is melted by this discharge energy. The electromagnetic force is turned off at an appropriate time, and a pressing force directed toward the base material is applied to the stud by the spring. The molten metal fills the inner space of the ferrule and then solidifies, completing the welding of the stud tip to the base material. After the welding is completed, the ferrule is crushed and removed.

JP 2002-307167 A

  Such stud welding is often used when a reinforcing bar is abutted and welded to a base material. As a stud, in addition to a round steel bar having a uniform circular cross section, as shown in FIG. 9, a protrusion comprising an axial rib and a circumferential node on the surface of a cylinder in order to increase adhesion to concrete as a reinforcing bar. A so-called deformed stud a in which b is formed may be used.

  In this case, as shown in FIG. 9, the upper opening of the ferrule is opened from the tip of the stud so that a gap is not generated as much as possible between the upper opening d of the ferrule c and the stud passing therethrough. It was customary to remove the protrusions b and use them in the range up to the area where they could pass. The reason for this is to prevent welding defects called blowholes, which are generated when external air enters the ferrule and air is mixed into the molten metal due to heat generated by arc discharge.

  However, in the welding method using the conventional deformed stud as described above, there is a problem that an increase in cost is inevitable because a pre-process of cutting a predetermined range of protrusions of the deformed steel bar is necessary. In addition, because the deformed steel bar is welded to the base metal with some ribs removed, the strength as a reinforcing bar becomes uneven in the longitudinal direction, and stress is concentrated in the welded part. The problem is also latent.

  The present invention has been conceived under the above circumstances, and this deformed stud can be used without requiring a pre-processing such as cutting out the protrusion from the deformed stud having the protrusion on the outer periphery of the steel bar. It is an object to enable proper stud welding, and more specifically, an improved ferrule and a stud welding method using the improved ferrule are provided and are preferably used in this method. It is also intended to provide a specially shaped stud.

  In order to solve the above problems, the present invention employs the following technical means.

  The ferrule for stud welding according to the first aspect of the present invention has a cylindrical shape that is open at both ends in the axial direction as a whole, has a stud insertion hole at one axial end, and the stud insertion at the other axial end. A ferrule main body having an internal space continuous with the hole, and a nonflammable shield portion extending in a flange shape toward the inside of the stud insertion hole and easily deformable.

  In a preferred embodiment, the shield part is formed by sticking a shield member having a donut disk shape as a whole to an end face on one end side in the axial direction of the ferrule body.

  In another preferred embodiment, the ferrule body has a stepped portion formed at a boundary between the stud insertion hole and the inner space having a larger diameter than the stud insertion hole, and the shield portion is a donut disk as a whole. It is formed by sticking a shield member having a shape to the stepped portion.

  According to the stud welding ferrule having such a configuration, even when the stud having irregularities such as the formation of longitudinal ribs and lateral nodes on the surface is inserted into the stud insertion hole, the shield portion is While being deformed, it is possible to create a state in which the clearance between the inner surface of the stud insertion hole and the surface of the stud is appropriately shielded. Moreover, since this shield part has nonflammability, arc discharge occurs between the stud and the base material, and the above shield state is still maintained even in a high temperature state where the tip of the stud is melted. be able to. Therefore, it is possible to suitably prevent outside air from entering the ferrule body through the gap between the stud insertion hole and the stud during the welding operation, and to prevent occurrence of welding defects such as blow holes.

  In addition, since the stud can be used with the unevenness left on the surface, a pre-processing such as removing the unevenness as in the prior art becomes unnecessary, which is advantageous in terms of cost. In addition, it is possible to prevent a decrease in strength as a reinforcing bar of the stud after welding.

  In a preferred embodiment, the whole donut-shaped shield member can be divided into a plurality of parts in the circumferential direction.

  According to such a configuration, the tip of the shield member adheres more easily to the uneven surface of the stud inserted through the stud insertion hole, and the shielding effect can be enhanced. In addition, the ferrule body performed after the end of the welding operation It will not be an obstacle to splitting and crushing.

  In a preferred embodiment, a solvent holding member is fitted in the internal space of the ferrule body.

  According to such a configuration, a reliable arc discharge can be caused.

  The stud welding method according to the second aspect of the present invention uses the stud welding ferrule according to the first aspect of the present invention, and the stud insertion hole of the stud welding ferrule has an end of a stud having irregularities on the surface. It is characterized in that it is carried out in a state where it is inserted through.

  According to such a configuration, the same advantages as those described above for the first aspect of the present invention can be obtained.

  The stud according to the third aspect of the present invention is a stud used in the stud welding method according to the second aspect of the present invention, wherein the rod-shaped metal member has irregularities on the surface, and a solvent adheres to the tip. It is characterized by being allowed.

  By using such a stud, even if it is a stud having irregularities on the surface, a welding operation is performed in combination with the ferrule for stud welding according to the first aspect of the present invention simply by attaching a solvent to the tip of the stud. By doing so, it is possible to perform appropriate welding without welding defects such as blow holes. Further, as described above, it is not necessary to perform a previous step of partially removing the unevenness on the surface.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the drawings.

  Hereinafter, a preferred embodiment of the present invention will be specifically described with reference to the drawings.

  1 to 4 show a first embodiment of a stud welding ferrule (hereinafter simply referred to as a ferrule) according to the present invention.

  The ferrule 10A has a cylindrical shape penetrating in the axial direction as a whole, and includes a ferrule body 20 made of a ceramic molding formed of, for example, an MgO—Al 2 O 3 —SiO 2 base material. The ferrule body 20 has an outer diameter on one axial end side smaller than an outer diameter on the other axial end side. A stud insertion hole 21 having a predetermined inner diameter is formed on one end side in the axial direction, and an internal space 22 continuous with the stud insertion hole 21 is formed on the other end side in the axial direction. The inner space 22 has an inner diameter larger than the inner diameter of the stud insertion hole 21, and therefore, a step portion 23 is formed at the boundary between the stud insertion hole 21 and the inner space 22. In addition, a plurality of concave grooves 25 extending radially are formed on the end surface of the ferrule body 20 on the other end side in the axial direction, as clearly shown in FIG.

  A shield member 30 in the form of a donut disc is attached to the end face on one end side in the axial direction of the ferrule body 20 by using an appropriate adhesive member. This shield member 30 is formed by, for example, stacking a plurality of cloths made of non-combustible fibers such as carbon fibers, and is a member that has non-combustibility and can be easily deformed by an external force. In the embodiment, the shield member 30 has an outer diameter substantially equal to the outer diameter on one end side in the axial direction of the ferrule body 20, and the inner diameter is smaller than the inner diameter of the stud insertion hole 21. Therefore, the shield member 30 has its inner peripheral side extended from the inner surface of the stud insertion hole 21 into an inward flange shape.

  In the embodiment shown in the figure, the shield member 30 can be easily separated into a plurality of parts by an external force, such as by inserting a plurality of slits 31 from the inner peripheral side, as clearly shown in FIGS. It is. Moreover, you may stick the segment previously divided | segmented into plurality to the end surface of the ferrule main body 20. FIG.

  In FIG. 1, the code | symbol 50 shows the stud which uses and welds in combination with the ferrule 10A of the said structure. This stud 50 is not a round bar, but is formed on the surface by forming a protrusion 51 that is a combination of a bulging rib 51a extending in the axial direction and a bulging node 51b extending in the circumferential direction on the outer periphery of the cylinder. Unevenness is formed. The stud 50 is obtained by cutting a reinforcing bar member having the projection 51 as described above into a predetermined length, and a solvent 55 made of aluminum or the like is provided at a tip portion to be welded to the base material 60. Is attached.

  As shown in FIG. 1, the inner diameter of the stud insertion hole 21 of the ferrule body 20 corresponds to the maximum outer diameter of the stud 50, that is, the outer diameter at the top of the protrusion 51, and the top of the protrusion 51 and the stud The clearance between the inner surface of the insertion hole 21 is set to be a necessary minimum. Further, the inner diameter of the donut disk-shaped shield member 30 corresponds to the minimum outer diameter of the stud 50, that is, the outer diameter of the portion where the protrusion 51 is not formed, so that the shield member 30 is radially inward. The tip of the stud 50 is set so as to be slightly separated from or slightly in contact with the portion of the stud 50 where the protrusion 51 is not formed.

  Stud welding using the ferrule 10A and the stud 50 configured as described above is performed as follows.

  As shown in FIG. 1, the ferrule 10 </ b> A is attached to the tip of the stud 50 so that the tip of the stud 50 is inserted into the stud insertion hole 21. Thus, the stud 50 with the ferrule 10A attached thereto is attached to a chuck of a stud welding machine (not shown). The stud welding machine is operated so that the tip of the stud 50 is pressed against the base material 60, and the stud welding machine is operated. Since the shield member 30 can be easily deformed, it is possible to obtain a mounting state of the ferrule 10A as shown in FIG.

  The ferrule 10A is pressed against the base material 60 by a ferrule pressing guide (not shown) on the stud welding machine side. In this state, the stud 50 is once pulled up with respect to the base material 60 by a predetermined distance, and then when a welding current is supplied between the stud 50 and the base material 60, the stud 50 is positioned between the tip of the stud 50 and the base material 60. Arc discharge occurs. This arc discharge easily occurs because the solvent 55 is attached to the tip of the stud 50. The tip of the stud 50 is melted by this discharge energy. Next, the pulling force with respect to the stud 50 is released, and a pressing force toward the base material 60 is applied to the stud 50 by the spring elasticity of the stud welding machine.

  Eventually, the molten metal fills the inner space 22 of the ferrule 10A and solidifies over time. In this process, the hot gas generated by the arc discharge fills the interior of the ferrule 10A, or such a hot gas. Although the state where the molten metal is mixed appears, at this time, as described above, the gap between the stud insertion hole 21 and the stud 50 is maintained in a state where it is appropriately shielded by the nonflammable shield member 30. Is done. Accordingly, it is possible to appropriately prevent external air from entering the ferrule 10A from the stud insertion hole 21 of the ferrule 10A, and to effectively cause a welding defect such as a blow hole in the welded portion of the stud 50 with respect to the base material 60. Can be prevented.

  After the molten metal is solidified in the ferrule as described above, the ferrule 10A is crushed and removed by crushing it with a hammer. However, as described above, the shield member 30 is easily provided with a slit 31 or the like. Since it is separable, it isolate | separates simultaneously with crushing of the ferrule 10A. Therefore, the shield member 30 does not become an obstacle to crushing and removing the ferrule 10A.

  Moreover, although the stud 50 has unevenness on the surface, it is advantageous in terms of cost because it does not require a pre-process for removing the unevenness at the tip portion as in the prior art.

  Furthermore, since the stud 50 is properly abutted and welded to the base material 60 while leaving the surface unevenness over its entire length, it is possible to alleviate stress concentration at the welded portion, and as a reinforcing bar. It is also effective for maintaining strength.

  FIG. 5 shows a second embodiment of the ferrule according to the present invention. The ferrule 10B is the same as the ferrule 10A according to the first embodiment except that the donut-shaped shield member 30 is attached to the stepped portion 23 of the ferrule body 20. The detailed description is abbreviate | omitted using the same code | symbol as 1 embodiment.

  Also in the ferrule 10B according to the second embodiment, the inner peripheral portion of the shield member 30 extends in an inward flange shape inside the ferrule body 20, so that external air is ferruled during welding. In addition to being able to effectively prevent intrusion into the main body 20, the same advantages as described above for the first embodiment can be enjoyed.

  FIG. 6 shows a third embodiment of the ferrule according to the present invention. In this ferrule 10C, a solvent obtained by adhering a solvent such as aluminum to the center of one surface side bulging portion of a ferrous metal thin plate member on the ferrule 10A according to the first embodiment shown in FIGS. A configuration in which a holding member 40 is added is provided. Since the remaining configuration is the same as that of the ferrule 10A according to the first embodiment, the same reference numerals are given to the corresponding portions and the description thereof is omitted.

 As shown in FIG. 7, the solvent holding member 40 bulges the central portion of the substantially rectangular thin plate member 41 in a dome shape, and attaches the solvent 45 to the vicinity of the top portion of the bulging portion 43. It is a thing. The four corners 42 of the thin plate member 41 are folded with a spring property, and the inner wall of the internal space 22 of the ferrule body 20 is configured to be circumscribed with elasticity.

  As shown in FIG. 7, the solvent holding member 40 is mounted in the internal space 22 of the ferrule body 20 so that the bulging side faces the outside. Then, the solvent holding member 40 is held inside the ferrule body 20 by the four corners 42 elastically contacting the inner wall of the internal space 22 as described above.

  In the case of performing stud welding using the ferrule 10C according to the third embodiment, as shown in FIG. 6, a material obtained by cutting a steel bar having irregularities on the surface is used as it is. That is, it is not necessary to attach a solvent to the tip as in the case shown in FIG.

  In order to perform stud welding using the ferrule 10C according to the third embodiment, the first embodiment has been described above with the ferrule 10C fitted to the tip of the stud 50 as shown in FIG. The same welding operation is performed by a stud welding machine. The arc discharge is reliably induced by the solvent 45 of the solvent holding member 40 described above, whereby the thin metal plate member of the solvent holding member 40 or the tip portion of the stud 50 is melted. In such a welding process, the point that the inflow of external air into the ferrule is prevented by the shield member 30 is the same as that described above for the first embodiment. It will be apparent that the ferrule 10C according to the third embodiment can enjoy the same advantages as those described above for the first embodiment, without repeating detailed description.

  Note that the ferrule 10 </ b> C according to the third embodiment has an advantage that a step of attaching a solvent to the tip of the stud 50 is unnecessary.

  FIG. 8 shows a fourth embodiment of the ferrule according to the present invention. This ferrule 10D is obtained by adding a solvent holding member 40 similar to that described above for the third embodiment to the ferrule 10B (FIG. 5) according to the second embodiment. Stud welding using the ferrule 10D can be performed in the same manner as described above for the third embodiment. Thus, also in the fourth embodiment, the same advantages as in the third embodiment can be enjoyed.

  Of course, the scope of the present invention is not limited to the configurations of the above-described embodiments, and all modifications within the scope of the matters described in the claims are all included in the scope of the present invention.

What is necessary is just to change suitably the specific shape and magnitude | size of the ferrule main body 20 according to the diameter of the stud 50 to be used. The shield member may be any material as long as it is nonflammable and can be easily deformed. The point is that the clearance between the stud insertion hole 21 in the ferrule body and the surface of a so-called deformed stud having irregularities on the surface may be sealed according to the irregularities.

It is sectional drawing which shows 1st Embodiment of the ferrule for stud welding which concerns on this invention. It is a top view of the ferrule shown by FIG. It is a bottom view of the ferrule shown by FIG. FIG. It is a whole perspective view of the ferrule shown by FIG. It is sectional drawing which shows 2nd Embodiment of the ferrule for stud welding which concerns on this invention. It is sectional drawing which shows 3rd Embodiment of the ferrule for stud welding which concerns on this invention. It is a bottom perspective view of the solvent holding member shown in FIG. It is sectional drawing which shows 4th Embodiment of the ferrule for stud welding which concerns on this invention. It is explanatory drawing of a prior art example.

Explanation of symbols

10A, 10B, 10C, 10D Ferrule 20 Ferrule body 21 Stud insertion hole 22 Internal space 23 Step portion 25 Concave groove 30 Shield member 31 Slit 40 Solvent holding member 41 Plate material 42 Corner portion 43 Swelling portion 45 Solvent 50 Stud 51 Projection 55 Solvent 60 base material

Claims (7)

A ferrule body having a cylindrical shape with both axial ends open as a whole, a stud insertion hole on one axial end side, and an internal space continuous with the stud insertion hole on the other axial end side;
A ferrule for stud welding, comprising a nonflammable shield portion that extends in a flange shape toward the inside of the stud insertion hole and can be easily deformed.   The ferrule for stud welding according to claim 1, wherein the shield part is formed by sticking a shield member having a donut disk shape as a whole to an end face on one end side in the axial direction of the ferrule body.   The ferrule body has a step formed at the boundary between the stud insertion hole and the inner space having a larger diameter than the stud insertion hole, and the shield part is formed by connecting the shield member having a donut disk shape as a whole to the step part. The ferrule for stud welding of Claim 1 currently formed by sticking to.   The ferrule for stud welding according to claim 2 or 3, wherein the shield member having a donut shape as a whole can be divided into a plurality of parts in the circumferential direction.   The ferrule for stud welding according to any one of claims 1 to 4, wherein a solvent holding member is fitted in the internal space of the ferrule body.   The stud welding ferrule according to any one of claims 1 to 4, wherein the stud is formed in a state where the tip of the stud having irregularities on the surface is inserted into the stud insertion hole of the stud welding ferrule. Welding method.   The stud for use in the stud welding method according to claim 6, wherein the surface of the rod-shaped metal member has irregularities, and a solvent is attached to the tip.

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