JP3531900B2 - Welding wire feeder and method - 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 wire feeding device for feeding a welding wire to a welding torch, and more particularly, a welding wire is pushed into one end of a wire insertion tube from a welding wire coil which is a welding wire source. The present invention relates to a welding wire feeding device including a wire pushing device (wire pusher) and a wire pulling device (wire pull) that pulls out a welding wire at the other end of a wire insertion tube and feeds the welding wire to a welding torch.

[0002]

2. Description of the Related Art Conventionally, both a wire pusher and a wire pull are equipped with an electric motor to rotate a roller for holding the wire (for example, Japanese Utility Model Publication No. 55-1729).

In order to maintain high welding quality, welding
It is necessary to keep the welding arc stable, and it is necessary to feed the welding wire to the welding torch so as to keep the welding arc length constant. For this purpose, it is preferable that the wire pulling speed and the wire pushing speed of the wire pull electric motor (pull motor) and the wire pusher electric motor (push motor) are completely the same. However, in reality, a speed difference occurs. Therefore, generally, a master and a slave are set for both electric motors, and the wire feeding speed is controlled by the electric motor on the master side, and the electric motor on the slave side is controlled with respect to this wire feeding speed. The wire feeding speed of the welding machine is increased by about 5 to 20%, and the welding wire is fed to the welding torch while the slave side wire drive roller is slipping with respect to the welding wire.

For example, wire feeding control is performed on a push motor, and the pull motor is always rotationally driven at a speed of about 5 to 20% higher than that of the push motor, and the drive roller is driven on the pull motor side. Slip on the welding wire. The speed of the push motor is set or adjusted by one knob for adjusting the wire feeding speed using the dual volume, and the speed of the pull motor is automatically determined in conjunction with this. ing.

[0005]

Within the narrow range of the welding wire feeding load fluctuation, the wire feeding between the pull motor side and the push motor side is good due to the slip on the pull motor side. The buffer range of the fluctuation of the welding wire feeding load due to the slip is narrow. If the movement of the welding wire suddenly stops on the pull motor side due to wire clogging of the tip of the welding torch, wire welding, etc., the push motor side does not reach the stop, but between the push motor side and the pull motor side. Buckling of the welding wire occurs. In the case of an abrupt stop as described above, buckling also occurs between the pull motor side and the tip of the welding torch, but before cleaning the welding torch or replacing the tip, the buckling point should occur. By cutting the welding wire, it is easy to reset the welding wire, and the length of the discarded wire is extremely short.

However, when buckling occurs between the push motor side and the pull motor side, since the distance from the buckling point to the tip of the welding torch is long, the welding wire should be placed in front of the buckling point. If cut, not only is the waste wire length long and uneconomical, but also the work of passing the welding wire through the conduit cable (welding wire insertion tube) that guides the welding wire must be performed again, which reduces workability. Invite. In order to avoid this, it is possible to extend the buckling point and straighten it, but in this case, if the straightening is insufficient, the previous buckling point is likely to be clogged with a conduit cable or a welding torch. . Therefore, it is preferable to minimize the possibility of buckling between the push motor side and the pull motor side.

The first object of the present invention is to prevent buckling of the welding wire between the push motor side and the pull motor side, and the second object is to achieve this easily. To do.

[0008]

[Means for Solving the Problems] (1) Welding wire coil
A roller that pulls out the welding wire from (4) and pushes it into one end of the wire insertion tube (3), and an air motor that drives this roller.
(4m); and a roller for feeding the welding wire pushed into the wire insertion tube (3) to a pull-out welding torch (Tw) at the other end side of the wire insertion tube, and an electric drive for rotating the same. Welding wire feeder with motor (6m). In addition,
For ease of understanding, the reference numerals of the corresponding or corresponding elements of the embodiments shown in the drawings and described later are added in parentheses for reference.

(2) An air motor (4 m) for rotating a roller for pulling out the welding wire from the welding wire coil (4) and pushing it into one end of the wire insertion tube (3) is supplied with air at a constant pressure. The welding wire supplied and pushed into the wire insertion pipe (3) is pulled out at the other end of the wire insertion pipe by a welding torch (T
The electric motor (6m) that rotationally drives the roller fed to
A method for feeding a welding wire, in which the feeding speed of the welding wire is controlled so as to match a target feeding speed of the wire.

The air-motor (4 m) uses high-pressure air as a power medium, and generally generates a rotational torque according to the differential pressure between high pressure and atmospheric pressure, but since the air-is compressible. When the drive load increases, the load drive rotation speed decreases, and when the drive load decreases, the load drive rotation speed increases. When the driving load is momentarily increased, the air is compressed in the air motor, and the kinetic energy of the motor mechanism is absorbed by the air in the motor. When the driving load is momentarily decreased, the air is compressed. -Mo-
Since the air expands in the motor to give kinetic energy to the motor mechanism, the change of the rotation speed corresponding to the load change is fast, and the motor mechanism is not mechanically impacted.
If the drive load rises too much, the rotation of the air-motor will stop immediately.

Therefore, the air of the wire pusher (4)
The motor (4m) is automatically linked to the wire feeding speed of the pull motor (6m) via the welding wire. On the pull motor (6m) side, if the welding wire movement stops suddenly due to wire clogging or welding of the tip of the welding torch, the air motor (4m) will stop immediately. (4m)
Side does not cause buckling of the welding wire between the side and the pull motor (6m) side.

Air is supplied to the air motor (4 m) at a constant pressure, and the pull motor (6 m) is speed-controlled so that the welding wire feeding speed matches the target wire feeding speed. As a result, the welding wire is fed to the welding torch (Tw) at the target wire feeding speed, and the rotation speed of the air motor (4 m) is automatically adjusted by the pull motor via the welding wire. The wire feed speed on the (6m) side is matched, the wire speed control of the pull motor (6m) is stabilized, and the wire feed speed control accuracy is improved.

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

[0014]

DETAILED DESCRIPTION OF THE INVENTION

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the outline of one embodiment of the present invention. The traveling carriage 1 equipped with the welding torch Tw welds the groove while traveling on a rail installed in parallel with a groove (not shown) between two steel plates to be welded. Welding tool on traveling carriage 1
A power cable, a control cable and a gas cable are connected between the electric power equipment, the gas power source, the gas cylinder and the control box on the work floor. The welding wire of the pail pack 4 is drawn out by the wire pusher 5 and passed through the conduit cable (welding wire insertion tube), and then drawn by the wire pull 6 on the traveling carriage and fed to the welding torch Tw.

An operation pendant that can be carried by an operator is connected to a control box on the table of the cable winder 2.
At the cable winder 2, the above-mentioned respective cables connected to the equipment on the work floor side are put together into one welding cable 3, and the cable 3 is wound up by the cable. It is wound in a spiral shape on the flat plate surface of the turntable of the machine 2. The welding cable 3 is connected to the traveling carriage 1.

When welding is performed, the traveling carriage 1 is driven to the farthest welding start position (groove starting end portion) from the winder 2 while the welding cable 3 is being unwound from the winder 2 and welding is started there. Then, the traveling carriage 1 is driven in the direction of approaching the winding machine 2 along the groove, and the welding cable 3 is wound up on the winding machine 2 in accordance with this welding traveling of the traveling carriage 1. During this welding, the speed corresponding to the welding speed (truck traveling speed) is set as a target value, and the traveling wire 1 is mounted on the traveling cart 1 so that the feeding speed of the welding wire to the welding motor Tw matches the target value. The wire feeding controller is a pull motor 6m which is an electric motor.
Control the speed of. The wire is clamped by a roller (not shown) of the wire pull 6, and the pull motor 6m rotationally drives the roller via a speed reducer (not shown). As a result, the welding wire passing through the conduit cable of the welding cable 3 is pulled out from the conduit cable and fed to the welding torch Tw.

In the cable winder 2, the welding wire is unwound from the pail pack 4 by the wire pusher 5 and pushed into the conduit cable. That is, the welding wire pulled out from the pail pack 4 is clamped by the rollers of the wire pusher 5, and is passed through the reduction gear to the air mower.
A push motor 5m, which is a rotor, rotationally drives the roller.

In the present embodiment, the push motor 5m has a plurality of air cylinders arranged radially at an equal angular pitch around the axis of the output rotary shaft, and each air cylinder enters the output rotary shaft. An air distributor that connects a crank connected to a piston, and sequentially connects each air cylinder to a high pressure air port and a low pressure air port as the output rotary shaft rotates. -Distribution valve) mechanism is provided,
It is a radial piston type air motor. Air (not shown) -high pressure air of a source-supply pipe (air supply pipe) and low pressure air-
Pipe (intake pipe) and push motor 5m high pressure air port
An electromagnetic opening / closing valve is inserted between the low pressure air port and the low pressure air port. When the energization (rotational driving) of the pull motor 6m is started, the electromagnetic opening / closing valve is opened and the high pressure air port of the push motor 5m is opened. High pressure air is supplied to the port, air is sucked from the low pressure air port, and the push motor is 5 m.
Rotates. Next, the results of the implementation are shown.

Push motor TAM4-010S manufactured by Taiyo Iron Works Co., Ltd. Air-Number of cylinders: 3 Rated air-pressure: 5.1 (kgf / cm ² ) Maximum output: 73.5 (W) Maximum torque: 0.637 (N .M) Maximum output speed: 1100 (rpm) Pull motor 6m No load current: 0.18 (A) Rated current: 0.9 (A) Motor restraint current: 1.4 (A) ( Overload current when welding wire SM-1F with a diameter of 1.4 mm was stopped during wire feeding at 18 m / min) Wire feeding stable area: 0.4 to 0.5 (A) or less Conduit case Inner diameter of cable: 3.5 mm Length: 10 m Minimum diameter of winding loop in cable winder 2: Approximately 0.8 m Number of winding loops with the cable wound: 4 Welding Condition Welding a cross pillar with a length of 5 m with a leg length of 12 mm Welding current: 390 (A) (Wire supply speed 1 ~15m
/ Min) Welding voltage: 40 (V) Welding speed: 28 (cpm).

Without welding, only the welding wire was fed under the conditions shown in Table 1 below, but there was no problem in feeding the welding wire.

[0022]

[Table 1]

In addition, the push motor 5m is 4.0Kgf
Welding torch Tw when supplying air / cm ²
When the welding wire was locked at the tip of the wire, the rotation of the push motor 5m stopped, and the wire pusher 5 and the cable
In Bull 3, the buckling of the welding wire did not occur. Welding was performed under the conditions shown in Table 2 below.
And in cable 3, buckling of the welding wire did not occur.

[0024]

[Table 2]

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a welding system according to an embodiment of the present invention.

[Explanation of symbols]

1: Welding trolley 2: Cable winder 3: Welding cable 4: Pail pack 5: Wire pusher 5m: Push motor 6: Wire pull 6m: Pull motor Tw: Welding torch

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-47-7979 (JP, A) JP-A-48-65142 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B23K 9/12 B23K 9/133

Claims (2)

(57) [Claims] 1. A roller for pulling out a welding wire from a welding wire coil and pushing it into one end of a wire insertion tube, and an air motor for rotationally driving the roller; and a welding wire pushed into the wire insertion tube. A welding wire feeder comprising a roller for feeding to a pull-out welding torch at the other end of the insertion tube and an electric motor for rotationally driving the roller. 2. A welding wire is pulled out from the welding wire coil and is pushed into one end of the wire insertion tube. Air is supplied at a constant pressure to an air motor which drives a roller to rotate and is pushed into the wire insertion tube. At the other end of the wire insertion tube, the electric motor that drives the roller that feeds the welding wire to the pull-out welding torch at the welding wire feeding speed matches the target wire feeding speed. Welding wire feeding method with speed control.