JP2926303B2 - Rebar welding aid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding aid used for welding reinforcing steel by a carbon dioxide shielded arc welding method.

[0002]

2. Description of the Related Art Conventionally, when two opposing ends of two adjacent reinforcing bars are welded by a gas shielded arc welding method using carbon dioxide gas or the like, a circular arc-shaped joint is formed on the outer periphery of the ends of the two reinforcing bars. Accordingly, it has been used as a receiving member for molten weld metal. As this kind of joint,
When an iron-made joint is used, the joint can be temporarily attached to the reinforcing bar by spot welding or the like, and then the main welding can be performed. However, when a ceramic joint is used, the joint cannot be temporarily attached by spot welding or the like.

Therefore, conventionally, two rebars to be welded are positioned and held by a jig so as to be arranged on the same axis, and the ceramic joint is supported by a support member which is a separate member from the jig. It is proposed that welding is performed while pressing against the above-mentioned rebar while holding the steel bar (Japanese Utility Model Application Laid-Open No. 5-7078).
No. 2 publication, FIG. 6).

Further, when performing this type of gas shielded arc welding outdoors, to prevent the shielding gas from being blown off by wind generated in the vicinity of the welded portion, it is necessary to perform the following steps.
It has been proposed to provide a windshield member that covers the vicinity of the welding portion between the reinforcing bars and prevents the intrusion of wind into the welding portion (see FIGS. 9 and 10 of Japanese Patent Application Laid-Open No. 2-112897). In this case, a locking member composed of two spring plates is provided on opposite sides of the windshield member, each holding the outer periphery of the reinforcing bar by sandwiching the outer circumference of the reinforcing bar from both sides. The welding operation is performed in a state of being locked on the upper side.

[0005] As described above, when welding two rebars,
Usually, a predetermined route interval (groove interval) is provided between the opposite end faces of both rebars. To make this route interval constant, a length corresponding to the route interval is provided on the inner periphery of the joint. It has been proposed to protrude the spacer (see FIG. 1 of Japanese Utility Model Laid-Open No. 88889/1993).

[0006]

However, as described above, when welding is performed while the ceramic joint is pressed against the reinforcing bar by the support member, if the ceramic joint is displaced in the axial direction, the welding is not performed during the welding operation. Melted weld metal can no longer be reliably received by the ceramic joint,
There is a possibility that the weld metal leaks from the back side of the welded part. In particular, when performing a welding operation in a state where two rebars are set up in a vertical direction, the axial displacement of the ceramic joint is likely to occur between the time when the support member is attached to the rebar and the start of the welding operation. Instead, the ceramic joint may fall off between the reinforcing bar and the support member.

Further, in the above-mentioned conventional windshield, a pair of locking members are formed by two spring plates, respectively, and are locked to the reinforcing bars on both sides, so that both locking members are sandwiched together. Thus, there is a problem that the locking work is complicated.

Furthermore, even when welding is performed using the above-mentioned windshield member, the shielding gas is blown off under a strong wind of a certain degree or more, and it becomes difficult to reliably shield the welding portion. I have to do it. If the welding operation is continued under the strong wind as described above, the bending and tensile strength of the welded portion will be insufficient.

Conventionally, slag generated during welding accumulates in a position behind the welding portion, that is, in the vicinity of the joint, even under normal weather conditions that are not strong winds. It was easy to occur. If the above welding failure occurs when welding is performed using an iron joint, the back side of the welded portion is covered with the iron joint, and repair is impossible. Is cut and removed over a predetermined length to completely separate the two rebars once, and then both ends of the replenishment rebar having the same length as the cut portion are again welded to the two rebars, respectively. And the repair work becomes extremely complicated.

When a spacer having a length corresponding to the route interval between two rebars is provided on the inner periphery of the joint to make the route interval constant, a step of providing a spacer is added by adding a spacer. This complicates the manufacturing operation and increases the cost.

Further, conventionally, for example, when another reinforcing bar is welded to a reinforcing bar projecting about 1 cm from an indoor ceiling or floor surface using an iron joint, if a poor welding occurs, the above-mentioned ceiling or floor surface will be damaged. There is a problem that it is impossible to cut the rebar because the amount of protrusion from the wire is small, and repair cannot be performed.

[0012] welding aids rebar according to the present invention, it is an object that such to ensure the axial positioning of the welding joint to eliminate the above problems.

[0013]

According to a first aspect of the present invention, there is provided a welding auxiliary tool which is disposed at a predetermined distance from two opposite ends of two reinforcing bars to be welded. A jig which has a pair of holding portions for holding each of the holding portions, and a connecting portion for connecting the pair of holding portions, and is used for fixing the rebars at the time of welding; and a welding joint having an arc-shaped cross section. 2 above
A reinforcing member for welding the reinforcing bar, the supporting member supporting the reinforcing bar along the outer circumference of each end of the book, wherein each holding portion of the jig holds the reinforcing bar while covering at least about half of the outer circumference of the reinforcing bar. An arm portion, and a pressing tool for pressing and fixing the rebar to the arm portion, wherein the connecting portion is formed of a rod-shaped handle extending substantially parallel to the rebar to be welded, and the support member is used for the welding. A supporting portion for supporting the joint from the outside, and a pair of locking portions each of which is locked to the two rebars; axial ends of the welding joint on an inner periphery of the supporting portion of the support member; Positioning portions are provided for abutting the respective portions to perform positioning in the axial direction.

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

The welding aid of the first aspect is suitably used when a ceramic joint or the like is used as a welding joint. In this case, first, the ends of the two rebars to be welded are respectively inserted into the arms of the jig, and are pressed and fixed by the pressing tool in a state where a predetermined route interval is provided between the two rebars. Subsequently, a welding joint made of ceramic or the like is supported by the support portion of the support member, and is locked to the rebars by the locking portion. In this state, the welding joint is provided along the outer periphery of the ends of both rebars. Then, the above-mentioned 2 is formed by a gas shielded arc welding method using carbon dioxide gas.
Weld the rebar in the book.

According to the first aspect of the present invention, since the positioning portion for positioning in the axial direction by contacting both ends in the axial direction of the welding joint is provided on the inner periphery of the support portion of the support member. Above, the welding joint is not displaced in the axial direction, and the welding metal is reliably received by the welding joint during welding, so that a problem that the welding metal leaks from the back side of the welding portion is less likely to occur. In particular, even when welding two rebars in a vertical state, the lower end of the vertically positioned welding joint is positioned by the positioning portion, so that the welding joint is It does not shift in the axial direction and does not fall off between the reinforcing bar and the support member. In addition, since the connecting portion is configured as a rod-shaped handle, there is an advantage that the operator can easily handle the welding assist tool only by gripping the handle with one hand.

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 2, the welding apparatus for performing welding using the reinforcing steel welding tool according to the present embodiment uses a carbon dioxide gas shielded arc welding method, and includes a welding power supply and a control mechanism (not shown). It has a main body 1 which is built in and has an instrument panel / operation panel 1a on the front. The main body 1 adjusts a carbon dioxide gas (shielding gas) supplied from a gas cylinder (not shown) to a predetermined jetting amount and a jetting pressure based on an operation amount of an operator, and then, through a hose 2, to a tip thereof. , And carbon dioxide gas is blown from the opening at the tip of the blow-out tube 3.

In this embodiment, the amount of the carbon dioxide gas jetted is increased from the conventional one, and is in the range of 30 to 120 liters per minute.
More preferably, it is set in the range of 50 to 120 liters per minute. The voltage of the welding power source is preferably 2
In the range of 8-35 volts, the current flowing is preferably 20
It is set in the range of 0-260 amps. In the middle of the hose 2 and in the vicinity of the ejection pipe 3, an operating tool 2a for turning on / off the welding operation is provided.

A wire supply pipe 5 for supplying a welding wire 4 (see FIG. 1) wound on a roll (not shown) is built in the hose 2 and the ejection pipe 3 substantially coaxially. The tip of the supply pipe 5 projects slightly from the tip opening of the ejection pipe 3.

As shown in FIG. 1, the welding aid includes a jig 11 made of steel or the like for positioning and holding two rebars 10 to be welded on the same axis, as shown in FIG. A welding joint 12 (hereinafter, simply referred to as a joint 12) made of ceramic and having an arc-shaped cross section having a central angle of about 180 ° is supported from the outside. 1 along the outer periphery of both rebars 10
The support member 13 is locked from the middle and below, and is locked to the two rebars 10 from above in FIG. 1 to cover the vicinity of the welded portion and to block the wind from being blown into the welded portion during welding work. A windshield member 14 is provided. Here, a case is shown in which a deformed steel bar having a plurality of large-diameter flange portions 10a provided on the outer periphery at predetermined axial intervals is used as the reinforcing bar 10, but the reinforcing bar 10 is, for example, the large-diameter flange. Part 1
In addition to Oa, one having a projection extending in the axial direction, or one having no large-diameter flange portion 10a and the above-described axial projection may be used.

As shown in FIG. 4, the jig 11 has a pair of holding portions 15 for holding the reinforcing bars 10 and a hollow extending parallel to the axial direction of the reinforcing bars 10 when holding the reinforcing bars 10 to be welded. It has a rod-shaped handle 16 and a pair of connecting portions 17 for connecting both ends of the handle 16 in the axial direction and each holding portion 15. The handle 16 and the connecting part 17 constitute a connecting part 19 for connecting the holding parts 15 together.

Each holding section 15 has an arm section 18 for holding the outer periphery of the end of the reinforcing bar 10 from outside. The arm portion 18 includes a flat wall portion 18a and a rectangular wall portion 18b facing the wall portion 18a, and is formed to have a substantially polygonal cross section as a whole. Pressing bolt 20 is screwed. The pressing bolt 20 presses the reinforcing bar 10 near the bent portion 18c of the wall portion 18b, thereby fixing the reinforcing bar 10 in the arm portion 18. Therefore, the pressing bolt 20 is
8c.

As shown in FIG. 5, the support member 13 has a support portion 22 having a substantially arc-shaped cross section for supporting the outer periphery of the joint 12 from the outside, and a pair of support members 22 provided integrally on both sides of the support portion 22. And a locking portion 23. Each locking part 23
The support member 13 is elastically locked to the reinforcing bar 10 by sandwiching the outer periphery of each reinforcing bar 10 from each side with a pair of spring plates 23a. Support part 2
The radius of curvature of the inner periphery of No. 2 is set to be substantially equal to the radius of curvature of the outer periphery of the joint 12.

Further, on the inner periphery of the support portion 22, there is provided an arc-shaped positioning member 22a (positioning portion) for abutting on both axial ends of the joint 12 to position the joint 12 in the axial direction. These positioning members 22 a
2 and may be provided integrally with each other, or another member may be attached by bonding or the like. Instead of the positioning member 22, for example, a step may be provided on the support portion 22, and the joint 12 may be positioned in the axial direction by the step.

As shown in FIG. 6 and FIG.
Are formed in a box shape with only two directions facing each other open, and the cross-sectional area thereof is changed from one opening 24 side to the other opening 2.
Each of the wall portions 26 to 29 is formed in a trapezoidal shape so as to gradually increase toward the fifth side. An arc-shaped notch 31 corresponding to the outer peripheral shape of the reinforcing bar 10 is provided at a portion facing the opening 24 in the pair of wall portions 26 and 27 facing each other.
Are provided respectively.

On the outer surface side of the wall portion 26, the outer periphery of one rebar 10 to be welded can be sandwiched from both sides.
A first locking portion 32 is provided, which includes a pair of spring plates 32 a and locks the windshield member 14 to one of the reinforcing bars 10. Furthermore, the other reinforcing bar 10 to be welded is
A second locking portion 33 made of a permanent magnet is provided. Then, with the notch 31 positioned in contact with the outer periphery of the reinforcing bar 10, the first and second locking portions 32, 3
3 allows the windshield member 14 to be locked to the reinforcing bar 10. In addition, the positioning of the windshield member 14 with respect to the reinforcing bar 10 can be sufficiently performed only by sandwiching the reinforcing bar 10 with the first locking portion 32.

At the time of performing the welding operation, first, as shown in FIG.
The jig 11 is inserted into the arm portion 18 of the pair of holding portions 15, and a predetermined route interval D is provided between the opposing end surfaces of both rebars 10 by measurement or visual measurement using a gauge (not shown). Then, in this state, both rebars 10 are brought into contact with the bent portions 18c (FIG. 4) of the wall portion 18b and tightened with the pressing bolts 20 to fix the rebars 10 in the holding portion 15.

Next, as shown in FIG. 9, the windshield member 14 is applied to the two rebars 10 from above in the figure, and after the first and second locking portions 32 and 33 lock the two rebars 10. As shown in FIG. 10, the support member 13 supporting the joint 12 in advance is attached to the locking portion 23 on the left side in FIG.
After being put on the locking portion 32, it is locked to both rebars 10. In this state, the joint 12 covers approximately half of the outer periphery of the ends of the reinforcing bars 10.

Then, as shown in FIG. 1, the jet pipe 3 is inserted into the windshield member 14 and arc welding is carried out while jetting carbon dioxide gas, so that the two rebars 10 are welded with the molten welding wire 4. I do. In this case, in the present invention, as described above, the amount of carbon dioxide gas spouted is increased as compared with the conventional case, and in addition, since the windshield member 14 is used, welding work can be performed even under a strong wind of about 20 m per second. Is hardly reduced. In addition, by increasing the amount of carbon dioxide blown out, the slag generated during the welding operation is blown off by the carbon dioxide gas, so that a large amount of slag is not accumulated at the welding portion, so that the welding strength is further improved. is there.

The amount of carbon dioxide spouted during welding may be adjusted within a range of 30 to 120 liters per minute based on the diameter of the reinforcing bar 10 to be welded and the wind speed at the work site during welding. More preferably, it is adjusted in the range of 50 to 120 liters per minute. The amount of carbon dioxide spouted by the conventional carbon dioxide shielded arc welding method is usually 25 liters or less per minute. It means that it is increasing. However, when welding extremely thin rebars 10 having a diameter of about 10 mm, practically, even if the ejection amount of carbon dioxide gas is set to about 20 liters per minute, which is 30 liters per minute or less, which is the lower limit of the present invention. Absent. In addition, when the welding operation is performed indoors, or when the wind speed is equal to or less than the predetermined value even when performing the welding operation outdoors, the windshield member 1
Welding may be carried out without using the steel 4.

In each of the above figures, the case where the welding work is performed by arranging the jig 11 and the reinforcing bar 10 substantially horizontally is shown. However, the work is performed by arranging the jig 11 and the reinforcing bar 10 so as to extend substantially in the vertical direction. You can do it too. In this case, in this embodiment,
Positioning member 2 provided on support portion 22 of support member 13
Since the joint 12 is positioned in the axial direction by 2a, even if the support member 13 and the joint 12 are arranged in a substantially vertical direction, the joint 12 does not fall off between the reinforcing bar 10 and the support member 13 and fall. The welding operation can be performed in a state where the joint 12 is securely positioned.

After the welding is completed, if it is necessary to inspect the strength of the welded portion, particularly the back surface covered with the joint 12 where welding defects are likely to occur, a sample should be extracted and subjected to a test such as bending and pulling. Or non-destructive inspection using X-rays or ultrasonic waves. Then, if the above inspection reveals a welding defect, the ceramic joint 12 is crushed and removed, and the defective weld metal on the back side of the welding site covered with the joint 12 is cut with a cutting tool. After the removal, the welded portion can be repaired by refilling the weld metal in a molten state into the cavity created by the cutting. In addition,
If the joint 12 is naturally crushed and falls off during the cooling period after welding, the operator can directly repair the joint 12 without crushing it.

In place of the ceramic joint 12, an iron joint 12 can be used.
After the two rebars 10 to be welded are positioned and fixed, the joint member 12 is preliminarily attached to the outer periphery of the end of one or both rebars 10 by spot welding or the like, so that the support member 13 is used. The main welding by the carbon dioxide gas shielded arc welding method can be performed without the need.

In this case, if a welding defect is found by the inspection after the end of the welding, as shown in FIG. 11, the carbide joint 37 as a cutting tool is used to cut the iron joint 12 from the back surface side and the vicinity of the welding portion. An opening 12f is provided in this opening 1
After the defective portion of the welded metal 4a having been welded is cut and removed through 2f, the welding metal 4a is cut through the opening 12f.
, It is possible to repair the welded portion. According to the experiment of the inventor, the time required for the repair is 3 hours even when cutting and re-welding by the carbide cutter 37 are combined.
It was a short time of about 0 to 150 seconds, and the repair success rate was extremely high.

FIG. 12 shows a modification of the joint. This joint 1
Numeral 2a is formed of iron, and a rectangular opening 12b is opened in the vicinity of a central welding portion. Further, a shielding member 12g made of ceramic having a rectangular shape larger than the opening 12b and having a curvature is provided.
By applying 2 g to the outer peripheral surface of the joint 12 a, the opening 1
2b is shielded. The radius of curvature of the inner circumference of the shielding member 12g is set to be substantially equal to the radius of curvature of the outer circumference of the joint 12a.

When welding the reinforcing bar 10 using the joint 12a shown in FIG. 12, the two reinforcing bars 10 are fixed as shown in FIG. 8, and the windshield member 14 is set as shown in FIG. . Thereafter, the shielding member 12g is first placed at the center of the support portion 22 of the support member 13 in FIG. 5, and the joint 12a is further placed thereon, and the positioning member 22 performs axial positioning. At this time, the shielding member 12g and the joint 12a may be fixed to each other with an adhesive or the like, or may be simply placed by overlapping the joint 12a on the shielding member 12g.

Then, a pair of locking portions 23 of the support member 13 supporting the shielding member 12g and the joint 12a are locked to the two rebars 10. Then, a welding operation is performed in the same manner as described above. After welding, if welding is defective and repair is required, the opening 12b is removed by removing the shielding member 12g.
The above-mentioned repair work can be easily performed via the.

The shielding member 12g in the joint 12a shown in FIG. 12 may be formed of a metal material having a non-welding property to iron, such as copper, in addition to the above-described ceramic. Further, as the shielding member 12g, a material obtained by forming an unfired clay material having a heat resistance to withstand a high temperature of about 1800 ° C. in a substantially arc-shaped cross section can be used. It is not particularly limited as long as it has the property.

FIG. 13 shows another modification of the joint. The joint 12a is formed of iron, and has a rectangular opening 12b near the center welded portion. A rectangular shielding member 12c is fitted into the opening 12b and fixed to the edge of the opening 12b by bonding or the like. The shielding member 12c is formed of a material having a non-welding property to iron, such as ceramic or copper. The shielding member 12c is 180
It may be formed of an unfired clay material having heat resistance of about 0 ° C. and filled in the opening 12b.

When welding is performed using the joint 12a, after fixing and holding the two rebars 10 with the jig 11, the joint 12a is temporarily attached to the two rebars 10, and the support member 13 is used. When the repair is required after welding, repair can be performed while the joint 12a itself is welded to the reinforcing bar 10 by crushing or separating the shielding member 12c.

The entire joint 12 shown in FIG.
It can also be formed of a glass-based material having heat resistance to withstand a high temperature of about 0 ° C. and non-adhesion to the reinforcing bar 10.
In this case, the two rebars 10 integrated after the welding is completed are separated from the joint 12, so that the joint 12 can be used repeatedly.

FIGS. 14 and 15 show modified examples of the windshield member.
This windshield member is basically configured in the same manner as the windshield member 14 in FIGS. 6 and 7, but the support 13a is provided at one end in the circumferential direction at the end of the wall portion 29 of the windshield member body 14a on the opening 24 side. In that it is rotatably mounted by a hinge 34. Support 1
Reference numeral 3a denotes a support portion 35 having an arc-shaped cross section for supporting the outer periphery of the joint 12 from outside, and is attached by welding or the like to one axial end portion on the inner peripheral side of the support portion 35. An engagement piece 36 (engagement portion) having an arcuate cross section protruding in the extension direction is engaged with the inner surface side of the wall portion 28 to thereby provide a windshield as shown in FIGS. The windshield member body 14a and the support member 13a are attached to the reinforcing bar 10 in a state where the reinforcing bar 10 is sandwiched between the member main body 14a and the support 13a from both sides. Further, in this state, the joint 12 supported by the support portion 35 is arranged along both rebars 10. In the windshield member main body 14a, the same reference numerals are given to portions having the same configuration as that of the windshield member 14, and the repeated description is omitted.

Hereinafter, another embodiment of the present invention will be described. The welding aid of this embodiment has a jig 40 made of steel or the like as shown in FIG. The jig 40 has a central angle of approximately 180
The cross-sectionally arc-shaped body 41 having an angle of 45 ° is provided. Further, both first arm portions 4 in the arcuate cross-section body 41 are formed.
A portion between the two, that is, an intermediate portion in the axial direction of the arc-shaped cross-section body 41 forms a connecting portion 49. By providing a step B on the inner periphery of the connecting portion 49 so as to have a larger diameter than the inner periphery of the first arm portion 42, a concave portion 43 having an arc-shaped cross section is formed. The step B is formed, for example, by
By welding a semi-cylindrical iron plate having a thickness B to both ends in the axial direction. Note that FIG. 17 does not show the iron plate in a separated state.

The joint 12d shown in FIG. 18 is supported by the arc-shaped bottom surface 43a of the concave portion 43. The radius of curvature of the bottom surface 43a is set to be equal to the outer diameter of the joint 12d, and the inner diameter of the first arm portion 42 is set to be equal to the inner diameter of the joint 12d.

A second arm 45 having an arc-shaped cross section with a central angle of approximately 180 ° is opened and closed at one circumferential end of each first arm 42 via a hinge 44 at one circumferential end thereof. Mounted freely. As is clear from FIG. 17, the inner diameter of the second arm 45 is set to be larger than the inner diameter of the first arm 42, and the inner diameter of the second arm 45 and the inner diameter of the recess 43 are set to be equal. The first and second arm portions 42 and 45, together with a lock portion 47 and a pressing bolt 56 to be described later, constitute a holding portion 46 for holding an end of the reinforcing bar 10 to be welded.

At the other end in the circumferential direction of each of the first and second arm portions 42 and 45, a lock portion 47 for locking the first and second arm portions 42 and 45 to each other is provided. That is, a pair of projections 48 are provided at the other end in the circumferential direction of each of the first arm portions 42 at predetermined axial intervals.
Projection 48 at the other circumferential end of each second arm 45
Are formed at a position corresponding to.

A support shaft 51 is rotatably supported between the adjacent projections 48, and a bolt 52 is integrally provided on the support shaft 51 so as to be substantially perpendicular to the support shaft 51. Bolt 5
A washer 53 is movably fitted to 2 and
A wing nut 54 is screwed to the bolt 52 outside the washer 53.

Then, as seen in the holding portion 46 on the right side in FIG. 17, the other end portions of the first and second arm portions 42 and 45 in the circumferential direction are joined to close the second arm portion 45. By rotating the bolt 52 upward together with the support shaft 51 to bring the washer 53 into contact with the upper surfaces of the projections 50 and tightening the wing nut 54 in this state, the first and second arm portions 42 and 45 are locked. State.

A screw hole 55 is formed at a substantially central position of the second arm portion 45, and a pressing bolt 56 as a pressing tool is screwed into the screw hole 55. Then, as described above, with the rebar 10 inserted into the holding portion 46 and the first and second arm portions 42 and 45 locked, the pressing bolt 56 is rotated in the forward direction, and the tip of the pressing bolt 56 is rotated. When a pressing force is applied to the outer periphery of the reinforcing bar 10 by the portion, the reinforcing bar 10 is pressed against the inner periphery 42 a of the first arm portion 42, whereby the reinforcing bar 10 is fixed in the holding portion 46.

As shown in FIG. 18, the joint 12d is formed of ceramic or the like into an arc-shaped cross section having a central angle of about 180 °, and is located at an axially intermediate position at one end in the circumferential direction. A space having an axial width corresponding to a space to be provided between adjacent ends of the reinforcing bar 10 and protruding in a tangent direction (A direction in FIG. 18) of an arc drawn by a cross section of the joint 12d. The projection 12e is provided integrally.

As shown in FIG. 19, the windshield member 14c used together with the jig 40 has four rectangular wall portions 57.
, And are formed in a box shape with the upper and lower sides open in the figure. At the center position of the upper end portion of the wall portion 57 in the figure, a permanent magnet 61 for attaching the jig 40 to the windshield 14 c is fixedly attached to the outer periphery of the second arm portion 45 of the jig 40. I have. An arc-shaped notch 62 corresponding to the outer peripheral shape of the reinforcing bar 10 is formed at the lower end of the walls 57 and 58 in the drawing.

In this embodiment, during the welding operation, as shown in FIG. 20, first, the joint 12d is inserted into the concave portion 43 of the jig 40 and supported by the bottom surface 43a. In this state, the inner periphery 42a of the first arm portion 42 and the inner periphery of the joint 12d form a continuous arcuate curved surface, and the joint 12d is formed by the end surface 43b of the concave portion 43 as a positioning portion (see FIG. 17).
Are positioned at both ends in the axial direction, so that movement in the axial direction becomes impossible.

Subsequently, as shown in FIG. 21, the opposite ends of the two rebars 10 to be welded are placed on the inner periphery 42a of the first arm 42 and the inner periphery of the joint 12d, and the two rebars 10 The root interval D set between the end faces is positioned so as to be substantially equal to the length of the interval checking projection 12e of the joint 12d, and the ends of both rebars 10 are held by the first and second arm portions 42 and 45, respectively. And locked by the lock unit 47. When using a joint having no projection 12e for confirming the interval, the route interval D is measured by a gauge or by visual measurement.
Should be determined.

Subsequently, as shown in FIG.
4c is inserted between the two second arm portions 45, and the permanent magnet 61 is attracted to the outer periphery of the second arm portion 45 on the left side in the figure to attach the windshield member 14c to the jig 40. It is inserted into the member 14c and the welding wire 4 is melted by arc heat to weld the reinforcing bars 10 together. When the welding operation is performed indoors, or when the wind speed is equal to or lower than a predetermined value even outdoors, welding can be performed without using the windshield member 14c.

FIG. 23 shows another embodiment of the jig. The jig 67 has an arc-shaped cross section 68 as a tubular body with an opening that covers half or more of the outer circumference of a reinforcing bar not shown in FIG. Both ends in the axial direction of the arcuate cross-section 68 constitute holding portions 70 for holding the ends of the reinforcing bars, and intermediate portions in the axial direction of the arcuate cross-section 68 are connecting portions for connecting the holding portions 70 together. 7
1.

Each of the holding portions 70 covers approximately 3/4 of the outer circumference of the reinforcing bar, and has an opening 76 for the remaining 1/4 of the circumference. Then, the rebar is connected to the small-diameter inner periphery 77 of the lower portion of the arm portion 72 in the drawing.
And a pressing bolt 73 (pressing tool) for pressing the pressing bolt.
The lower portion of the arm portion 72 in which the reinforcing bar is pressed has a smaller inner diameter than the side portion and the upper portion of the arm portion 72 in the drawing.
Is provided.

The recess 74 is formed, for example, by welding an iron plate having an arc-shaped section not shown separately to the lower part of the arm 72 on both sides of the recess 74. A notch 75 for attaching the windshield member 14c shown in FIG. 19 is formed at a side portion and an upper portion in FIG. 23 of the connecting portion 71, and the central angle of the connecting portion 71 is set to be substantially 180 °. ing.

When welding is performed by using the jig 67 shown in FIG. 23, first, for example, the joint 12 shown in FIG. Insert the end of the rebar. Then, with a predetermined route interval provided between the ends of the two reinforcing bars, the pressing bolt 7
The welding work may be performed after pressing the rebar to the small diameter inner periphery 77 of the arm 72 by 3 and fixing the same, and setting the windshield member 14c of FIG. 19 if necessary.

FIG. 24 shows a modification of the jig 67. In the jig 67a of this modification, a cylindrical body 68a having a polygonal cross section and having an opening 76a in a part in the circumferential direction is used in place of the arcuate body 68 in the cross section. , An arm 72 a having a polygonal cross section, and a pressing bolt 7
3a, and a connecting portion 71a having a polygonal cross section is provided at an axially intermediate portion of the tubular body 68a with an opening. On the inner periphery of the connecting portion 71a, for example, a concave portion 74a having an arc-shaped cross section for accommodating the joint 12d shown in FIG. 18 is provided. In this embodiment, the rebar is formed by the two bolts 8 by the pressing bolt 73a.
It is configured to be pressed and fixed in the vicinity of a bent portion 82 between 0 and 81. Thereby, the positioning accuracy of the rebar can be further improved.

Next, a welding procedure when welding is performed at a special position using the joint 12a shown in FIG. 13 will be described. FIG.
As shown in FIG. 5, for example, when another reinforcing bar 10 is connected to the reinforcing bar 10a having a protrusion amount C of about 1 cm vertically downward from the indoor ceiling 83, a predetermined route interval D is set between the reinforcing bar 10a and the reinforcing bar 10a. In this state, the rebar 10 is fixed and held by an appropriate method.

Subsequently, the joint 12a is temporarily attached to the reinforcing bars 10a and 10 by spot welding or the like, and then, main welding is performed by a carbon dioxide gas shielded arc welding method using the welding apparatus of FIG. After the main welding, if a strength inspection of the welded portion is required, a non-destructive inspection using X-rays or ultrasonic waves may be performed. As a result of the inspection, if the strength is insufficient, the shielding member 12c of the joint 12a is crushed or separated, and the welding portion can be repaired by the cutting tool through the opening 12b. When the amount of protrusion C of the reinforcing bar 10a is only about 1 cm as shown in FIG. 25, repair cannot be performed by a conventional method of cutting the reinforcing bars 10a and 10 over a predetermined length.

[0096]

As described above, the welding aid according to the present invention is provided with a positioning portion on the inner periphery of the support portion of the support member for performing axial positioning by contacting both ends of the welding joint in the axial direction. Since the welding joint is not displaced in the axial direction on the support member, the weld metal is reliably received by the welding joint at the time of welding, and a problem such as leakage from the back side of the welding site is less likely to occur. . In particular, even when performing welding work in a state in which two rebars are set up vertically, the lower end of the welding joint arranged vertically is positioned by the positioning portion. The joint does not shift in the axial direction and does not fall off between the reinforcing bar and the support member. Thus, the welding operation can be performed more reliably.

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[Brief description of the drawings]

FIG. 1 is a schematic front view showing a welding aid according to an embodiment of the present invention.

FIG. 2 is a perspective view of a welding device that performs welding by using the welding aid.

FIG. 3 is a perspective view of a welding joint used together with the welding aid.

FIG. 4 is a perspective view of a jig included in the welding aid.

FIG. 5 is a perspective view of a support member included in the welding aid.

FIG. 6 is a bottom view of a windshield member included in the welding aid.

FIG. 7 is a perspective view of a windshield member included in the welding aid.

FIG. 8 is a schematic front view showing a state where a reinforcing bar is held by the jig.

FIG. 9 is a schematic front view showing a state in which a windshield member is locked to the reinforcing bar.

FIG. 10 is a schematic front view showing a state in which a support member is further locked to the rebar.

FIG. 11 is a schematic front view showing a state in which a welded portion of the reinforcing bar is repaired.

FIG. 12 is a perspective view showing another embodiment of the welding joint according to the present invention.

FIG. 13 is a perspective view showing still another embodiment of the welding joint according to the present invention.

FIG. 14 is a perspective view showing another embodiment of the windshield member according to the present invention.

15 is a partial cross-sectional side view showing a state in which the windshield member of FIG. 14 is locked to a reinforcing bar.

FIG. 16 is a schematic front view showing a state where the windshield member of FIG. 14 is locked to a reinforcing bar.

FIG. 17 is a perspective view showing a jig included in another embodiment of the present invention.

FIG. 18 is a perspective view showing a welding joint used for the jig of FIG. 17;

FIG. 19 is a perspective view showing a windshield attached to the jig of FIG. 17;

FIG. 20 is a perspective view showing a state where a welding joint is set on the jig of FIG. 17;

FIG. 21 is a perspective view showing a state where a reinforcing bar is held by the jig of FIG. 17;

FIG. 22 is a schematic front view showing a state where a windshield is attached to the jig of FIG. 17;

FIG. 23 is a perspective view showing a jig according to another embodiment of the present invention.

FIG. 24 is a perspective view showing a jig according to still another embodiment of the present invention.

FIG. 25 is an explanatory view showing an example of welding by the welding joint of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Reinforcing bar 11 Jig 12 Welding joint 12a Welding joint 12b Opening 12c Shielding member 12d Welding joint 12e Spacing confirmation projection 12f Opening 13 Support member 13a Support 14, 14a, 14b, 14c Windshield member 15 Retaining part 16 Handle part 17 Connecting part 18 Arm part 19 Connecting part 20 Press bolt (Pressing tool) 22 Support part 22a Positioning member (Positioning part) 23 Lock part 31 Notch 32 First lock part 33 Second lock part 35 Support part 36 Engagement piece (Engaging part) 37 Carbide cutter (cutting tool) 40 Jig 41 Arc-shaped body 42 in cross section 42 First arm part 43 Depression 45 Second arm part 46 Holding part 47 Lock part 56 Pressing bolt (pressing tool) 57 Jig 58 Arc-shaped body 58a Cylindrical body with opening 60, 60a Holding part 61, 61a Connecting part 62, 62a Arm part 63, 63a Press bolt 64, 64a Recess 66, 66a Opening

Continuation of the front page (56) References JP-A-56-168997 (JP, A) JP-A-60-84196 (JP, U) JP-A-62-15866 (JP, U) JP-A-6-83183 (JP) , U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23K 37/06 B23K 37/053 B23K 9/038

Claims (1)

(57) [Claims] 1. A pair of holding portions, which are arranged at a predetermined interval and hold opposite ends of two rebars to be welded, respectively, and a connecting portion connecting the pair of holding portions. And a support member that supports a welding joint having an arc-shaped cross section along the outer periphery of each end of the two reinforcing bars. An arm part for holding the rebar while each holding part of the jig covers at least about half of the outer circumference of the rebar, and a pressing tool for pressing and fixing the rebar to the arm part. And the connecting portion is formed of a rod-like handle extending substantially parallel to the reinforcing bar to be welded, and the support member is engaged with the supporting portion for supporting the welding joint from outside and the two reinforcing bars, respectively. And a pair of locking portions. Welding aids rebar, wherein a positioning portion for positioning in the axial directions in the axial end portions of the inner periphery the welding joint of the support portion abuts the member.