JPH09327772A - Rotary arc welding torch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform the welding of a narrow part by reducing the outer diameter in the vicinity of a tip of a rotary arc welding torch. SOLUTION: A welding torch is provided with a torch body 3 capable of precession with an automatic aligning bearing 9 to support a rear end side, a supporting member 10 to support a middle part of the torch body 3, a cylindrical holder 4 to hold the outer circumferential side of the supporting member 10 in an eccentric manner, and a cylindrical housing 2 which houses the holder 4 and supports the forward end side and the rear end side by a first bearing 7 and a second bearing 8 in a rotatable manner, and the supporting member 10 comprises a deep groove ball bearing which is inclined by the angle formed by the center axis of the torch body 3 relative to the center axis of precession, and supported by the holder 4.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a rotary arc welding torch (hereinafter simply referred to as a torch). More specifically, the present invention relates to a torch for rotating the arc by rotating the tip of the torch at high speed to obtain a desired weld bead.

[0002]

2. Description of the Related Art Conventionally, in rotary arc welding, high-speed rotation is performed so that the arc has a cylindrical shape substantially equal to the rotation diameter of the tip of the torch. As a result, the molten metal is moderately dispersed by centrifugal force, which allows flattening of the shape of the base material to be melted and flattening of the beads, improving welding quality and increasing the melting speed of the welding wire to increase the welding speed. Can be improved.

[0003] Such a rotary arc welding apparatus includes:
Conventionally, Japanese Patent Publication No. 3-79108, Japanese Patent Publication No. 4-814
No. 8, Japanese Patent Publication No. 4-31791, Japanese Patent Publication No. 5-3
No. 6153, JP-A-4-333370, JP-A-5-69145 and JP-A-6-320282
The one disclosed in Japanese Patent Application Laid-Open Publication No. H10-260, 1993 is known.

In the torch used in the device disclosed in the above publication,
4, the rear end side of the torch main body 51 is swingably supported by a first self-aligning bearing 52, and an intermediate portion of the torch main body 51 is a second self-aligning bearing 53. Swingably supported by The second self-aligning bearing 53 is eccentrically contained in a disc-shaped support member 54, and the disc-shaped support member 54 is rotated by a rotary drive machine 55 such as a motor. As a result, the torch main body 51 performs precession with the first self-aligning bearing 52 as a fulcrum, and the tip 51a of the torch main body 51 performs high-speed circular motion.
Of course, the torch body 51 and the inner ring sides of the first and second self-aligning bearings 53 do not rotate, but only the disk-shaped support member 54 rotates. In addition, 56 is a bearing which supports the disk-shaped support member 54, and 57 is a pinion. Sometimes a belt drive is used instead of a pinion.

On the other hand, there is an increasing need for such a rotary arc welding apparatus to be applied to welding of a complicated welding line (welding locus), particularly a narrow portion, and for this purpose, it is necessary to reduce the size of the rotary torch. It is becoming. That is, there are many narrow portions N as shown in FIG. 5 in the welding work such as a bridge and shipbuilding. For example, 61 in the figure is a main structural member,
Reference numeral 62 is a reinforcing rib. Therefore, the space and gap of N are not generally large, and the R dimension shown in the industry is almost unified to a certain small value (for example, 35 mm).

Therefore, the smaller the outer diameter in the vicinity of the torch tip is, the easier the welding of the narrow portion becomes.

[0007]

However, in the above-mentioned torch, there is a limit in reducing the external dimensions near the tip due to its structure. That is, the second self-aligning bearing 5 mainly supporting the intermediate portion of the torch body 51
The outer diameter of 3 places such a restriction.

In order to reduce the size of the torch from the front end to the longest possible range, it is conceivable to move the eccentric mechanism provided with the second pivotal support member toward the rear end. However, since the circular motion of the tip of the torch is set to a small diameter, if the eccentric mechanism is moved away from the tip of the torch, it is necessary to reduce the amount of eccentricity of the torch body in the eccentric mechanism accordingly. Is difficult to obtain.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and has a smaller outer diameter as a bearing for supporting an intermediate portion of a torch body, instead of a self-aligning bearing. By using a certain deep groove bearing, the vicinity of the tip of the torch is made smaller. With such a configuration, the welding workability of the narrow portion is improved.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A torch according to the present invention comprises a torch main body capable of precession with a first pivot supporting member supporting the rear end side as a fulcrum, and a second pivot supporting an intermediate portion of the torch main body. A support member and a bearing for eccentrically supporting the outer peripheral side of the second pivot member, wherein the second pivot member forms a center axis of the torch body itself with respect to a precession movement center axis of the torch body. It is composed of a deep groove bearing which is supported by the bearing at an angle.

As described above, by adopting a deep groove bearing whose outer diameter is smaller than that of the self-aligning bearing having the same inner diameter and the same radial withstand pressure and the same axial withstand pressure, the intermediate portion of the torch can be obtained. In other words, the eccentric mechanism can be made smaller in diameter. As a result, the degree of freedom of movement of the torch with respect to the narrow portion is improved. In particular, it becomes easy to approach and enter narrow spaces.

In such a torch, the first pivot member is constituted by a self-aligning bearing, and the bearing is constituted by a deep groove bearing. The function and effect of the torch of the present invention described above while maintaining the performance of the conventional torch. This is preferable because

[0013] Also, a cylindrical holder in which the second pivot member is eccentrically disposed on the inner peripheral side, and a housing for enclosing the cylindrical holder are provided, and the distal end side of the cylindrical holder is provided inside the housing. Arranging the bearings that rotatably support the rear end side, respectively, and configuring the cylindrical holder to be rotationally driven by a rotary driving machine disposed in the housing, is that the torch is further rotated from its front end. This is preferable in that it can be formed in a small size over a long range.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A torch according to the present invention will be described below with reference to embodiments shown in the accompanying drawings.

FIG. 1 is a sectional view showing an embodiment of the torch of the present invention, and FIG. 2A is a schematic sectional view for explaining the structure of the torch of FIG. 1 taken along the line II-II. 2
FIG. 3B is a partially cutaway plan view of the portion, and FIG. 3 is an explanatory diagram showing the operation of the torch of FIG.

The torch 1 shown in FIG. 1 is of a belt drive type. A cylindrical holder 4 having a torch main body 3 is provided in a cylindrical housing 2 and is mounted on the outside of the cylindrical housing 2. The holder 4 is rotated via the belt 6 by the servo motor 5.

The holder 4 is rotatably supported at its rear end by a first bearing 7 fixedly mounted on the inner diameter side of the cylindrical housing 2, and also has a second end fixedly mounted on the inner diameter side of the cylindrical housing 2. It is rotatably supported by a bearing 8. Both the first bearing 7 and the second bearing 8 are constituted by deep groove ball bearings.
The first bearing 7 and the second bearing 8 correspond to bearings in the claims.

A portion of the torch main body 3 on the rear end side, which is separated from the holder 4, is directly gripped by a self-aligning bearing 9 (corresponding to a first pivot member in the claims). And the middle part of the torch body 3
It is gripped by a support member 10 (corresponding to a second pivot member in the claims) fixed to the inner diameter side of the holder 4. This support member 10 is also formed of a deep groove ball bearing.

As apparent from FIG. 2A, the support member 10 is eccentrically fixed to the holder 4. Thus, when the holder 4 is rotated, the torch main body 3 performs a precession motion (so-called slid-in motion) with the portion where the self-aligning bearing 9 is provided as a fulcrum. The cone angle of the precession is one side, and tan θ in FIG.
= L / d. L is the distance from the center of the self-aligning bearing 9 to the center of the support member 10,
d is the amount of eccentricity of the support member 10 with respect to the holder 4 (FIG. 2)
(See also (a)). In FIG. 2A and FIG. 3, the amount of eccentricity is shown larger than the actual amount for easy understanding.

Further, as shown in FIG. 2B, the central axis A of the supporting member 10 is fixedly mounted in a state inclined with respect to the central axis B of the holder 4. This inclination angle is matched with the one-sided cone angle θ of the precession movement of the torch body 3. In FIG. 2B and FIG. 3, the inclination angle is shown larger than the actual one for easy understanding.

In this embodiment, the cone angle θ is set to 0.229 °.
And the eccentricity d is planned to be 0.67 mm.

FIG. 2 shows the cylindrical housing 2, the second bearing 8, the support member 10, the holder 4 and the torch main body 3. The outer ring side of the support member 10 and the outer ring side of the second bearing 8 are respectively shown. It is not shown because it is fixed to the outer member. Also, the illustration of the structure inside the hollow torch body 3 which is originally hollow is omitted.

Hereinafter, the portion shown in FIG.

In FIG. 1, the welding wire supply mechanism, the torch cooling mechanism and the like are omitted. In FIG. 1, reference numeral 12 denotes a distal end housing, which is fixedly connected to the cylindrical housing 2 by a fixing bracket 13 and is not a rotating member. Therefore, when the holder 4 is rotated by the servomotor 5, only the torch main body 3 precesses, and the other members are fixed. Reference numeral 14 denotes a jacket forming the cooling water passage 14a, and reference numeral 15 denotes a shield gas injection port. Reference numeral 16 denotes a sealing member for preventing dust such as welding spatters entering from the tip of the torch from reaching the eccentric mechanism, and a structure and a flexible material capable of following the elliptical movement of the torch body 3 at that portion. Is used.

The operating state of the torch body 3 of the torch 1 configured as described above is shown in FIG. In FIG. 3, as described above, the tilt angle due to the precession movement of the torch body 3 is shown larger than it actually is for easy understanding. When the holder 4 is rotated by the servo motor 5 as shown in FIG.
The torch main body 3 performs a precession motion at an inclination angle θ about the center axis B of the torch 1 with the self-aligning bearing 9 as a fulcrum.
In that case, the inner ring side of the support member 10 is
It does not rotate because it is fixed to.

As described above, in the present torch 1, since the deep groove ball bearing is used as the torch body supporting member in the eccentric mechanism 11 of the torch body 3, the outer diameter of the eccentric mechanism 11 portion should be made smaller than that of the prior art. You can

That is, as an example, in the prior art, a self-aligning bearing having an outer diameter of about 40 mm is used for a torch body having an outer diameter of about 17 mm, but a deep groove ball bearing is used for the torch body having the same outer diameter. In this torch 1, the outer diameter of the bearing is about 26 mm. Therefore, in the torch 1, the outer diameter of the eccentric mechanism portion is about 14 mm smaller than that of the conventional torch. As a result, the maximum width of the torch can be reduced from about 72 mm to about 58 mm in the related art, and an approximate allowance of about 6 mm is secured for the R dimension of 35 mm in FIG. As a result, workability at the time of welding a narrow portion is greatly improved. There is no particular problem since the outer diameter of the torch from the eccentric mechanism portion to the distal end side does not become larger than the eccentric mechanism portion.

In this embodiment, a belt drive is used to rotate the holder 4. However, the present invention is not limited to the belt drive, and the torque may be transmitted using a gear mechanism, for example. .

[0029]

According to the torch of the present invention, the outer diameter of the eccentric mechanism near the tip can be made smaller than that of the conventional torch, so that the workability when welding a narrow portion is greatly improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a torch of the present invention.

FIG. 2A is a schematic cross-sectional view for explaining a configuration of a cross-section taken along the line II-II of the torch of FIG. 1, and FIG.
Is a partially cutaway plan view of the portion.

FIG. 3 is an explanatory diagram showing an operation of the torch of FIG. 1;

FIG. 4 is an explanatory view showing an example of a conventional torch.

FIG. 5 is a front cross-sectional view showing one welding construction example with a torch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Torch 2 ... Cylindrical housing 3 ... Torch body 4 ... Holder 5 ... Servo motor 7 ... First bearing 8 ... Second bearing 9 ... Self-aligning Bearing 10: Support member 11: Eccentric mechanism

Claims (3)

[Claims] 1. A torch body capable of precession with a first pivot member supporting a rear end side as a fulcrum, a second pivot member supporting an intermediate portion of the torch body, and the second pivot member A bearing that eccentrically supports the outer peripheral side of the torch, and the second pivot member is supported by the bearing at an angle formed by the center axis of the torch body itself with respect to the precession center axis of the torch body. Arc welding torch composed of deep groove bearings. 2. The rotary arc welding torch according to claim 1, wherein said first pivot member is constituted by a self-aligning bearing, and said bearing is constituted by a deep groove bearing. 3. A cylindrical holder in which the second pivot member is eccentrically arranged on the inner peripheral side, and a housing for enclosing the cylindrical holder, and the cylindrical holder is provided inside the housing. The bearing is provided to rotatably support the front end side and the rear end side, respectively, and the cylindrical holder is rotatably driven by a rotary drive machine provided in the housing. The rotary arc welding torch according to 1.