JP3027096U - Welding equipment - Google Patents

Abstract

(57) Abstract: In arc welding using a shield gas, the welding performance at the start of welding is improved and the shield gas cost is reduced. SOLUTION: A shield gas having a good welding performance is supplied at the time of starting welding, and when the state of arc formation is stabilized, another type of shield gas is switched and supplied. Therefore, the shield gas supply device (4a) can be selectively switched between at least two kinds of shield gas supply sources (41a, 41b) and at least two kinds of gas supply sources (41a, 41b). And,

Description

[Detailed description of the device]

[0001]

[Technical field to which the device belongs]

 The present invention relates to a welding device, and more particularly to an arc welding welding device using carbon dioxide gas or a mixed gas as a shield gas.

[0002]

[Prior art]

 In the welding of steel materials, the arc welding method that uses carbon dioxide gas or a mixed gas as a shield gas is widely used. The advantages of this welding method are that the mechanical properties of the welded part are as excellent as the welding method using a low-hydrogen coated arc welding rod, high efficiency, large penetration, welding in all positions. Are possible, visible arcs, etc. The characteristic feature of carbon dioxide as a shield gas is that it is much cheaper than the inert gas or mixed gas of argon or helium. The mixed gas has improved welding performance by adding another gas to carbon dioxide gas as compared with the case of carbon dioxide gas alone. As the mixed gas, a mixture of carbon dioxide gas with argon gas, a mixture of oxygen gas, a mixture of carbon monoxide gas, a mixture of argon gas and oxygen gas, and the like are used. For example, in a mixed gas of carbon dioxide gas and argon gas, the bead shape is improved, the amount of spatter is reduced, the arc temperature is increased, and the amount of penetration is increased. In the mixed gas of carbon dioxide and oxygen gas, the arc temperature rises, the melting rate of the wire increases, and the amount of penetration increases.

Conventionally, arc welding using this carbon dioxide gas or a mixed gas as a shield gas has been performed by a welding device having a configuration as shown in FIG. That is, in FIG. 2, the welding device is configured with a welding machine 1 having a control function, a wire feeding device 2, a welding torch 3, and a shield gas supply device 4 as main components. The welding machine 1 is connected by pipes so that the shield gas is supplied from the shield gas supply device 4 through the first connecting pipe 7a and the shield gas is supplied to the welding torch 3 through the second connecting pipe 7b. Has been done. Further, the welding machine 1 is connected so as to supply a welding current to the welding torch 3 via the first power cable 5a and to the workpiece 10 via the second power cable 5b. The wire feeding device 2 includes a wire reel 2 a and supplies a welding wire 6 to the welding torch 3. The shield gas supply device 4 is further composed of a gas cylinder (shield gas supply source) 41 filled with shield gas, a regulator 42 for adjusting the flow rate of the shield gas, and a third connecting pipe 43 for connecting both devices. .

With the welding apparatus configured as described above, in arc welding, a welding current is applied from the welding machine 1 to the welding torch 3 and the workpiece 10 via the first power cable 5a and the second power cable. The supplied shield gas of the gas cylinder 41 is supplied to the welding machine 1 through the third connecting pipe 43, the regulator 42 and the first connecting pipe 7a while the flow rate is adjusted, and further from the welding machine 1 to the second connecting pipe 7b. Is supplied to the welding torch 3, and the welding wire 6 is supplied from the wire feeder 2 to the welding torch 3.

[0005]

[Problems to be solved by the device]

 Since the conventional welding method and welding apparatus for arc welding using carbon dioxide gas or a mixed gas as the shield gas is configured as described above, the following problems exist. That is, welding is always performed using one type of shielding gas. Therefore, when carbon dioxide gas is used, from the start of welding until the arc formation state stabilizes, the penetration is insufficient, the bead shape is inferior, the amount of spatter is large, and it causes welding defects. Sometimes. In addition, when mixed gas is used, the problems like carbon dioxide gas do not occur even at the start of welding, but mixed gas is more expensive than carbon dioxide gas and the welding construction cost is high. Further, in the conventional welding apparatus, it is impossible to change the shielding gas during welding, that is, to replace the gas cylinder without making a sudden change in welding conditions while continuing welding.

The present invention has been made to solve the above problems, and in arc welding using carbon dioxide gas or a mixed gas as a shield gas, welding that improves welding performance at the start of welding at low cost. The purpose is to provide a device.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, in arc welding using a shield gas, the welding device according to the present invention supplies the shield gas with good welding performance at the start of welding, and when the arc formation state becomes stable, other It is characterized by switching and supplying to different types of shield gas.

More specifically, when the shield gas at the start of welding is switched to another type of shield gas, the supply of the other type of shield gas is stopped and then the supply of the shield gas at the start of welding is stopped. Is a welding device.

More specifically, the welding device is characterized in that the other type of shield gas is carbon dioxide gas.

Further, in arc welding using shield gas, the welding apparatus according to the present invention comprises a welder having a control function, a wire feeder, a welding torch, and a shield gas feeder. In the welding apparatus, the shield gas supply device is composed of at least two types of shield gas supply sources and a switching valve capable of selectively switching at least two types of the gas supply sources. It is a thing.

More specifically, the switching valve connects at least two inflow ports and the outflow port to communicate with each other, and at the same time, switches the communication state between the outflow port and any two inflow ports. The welding device is characterized in that the outlet and the arbitrary two inlets are simultaneously communicated.

[0012]

[Embodiment of device]

 A preferred embodiment of a welding apparatus for arc welding using a shielding gas according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is an overall configuration diagram of a welding device according to the present invention. In FIG. 1, the welding device is configured by using a welding machine 1 having a control function, a wire feeding device 2, a welding torch 3, and a shield gas supply device 4a as main components. The welding machine 1 is supplied with the shielding gas from the shielding gas supply device 4a via the first connecting pipe 7a and supplies the shielding gas to the welding torch 3 via the second connecting pipe 7b. Piping is connected. Further, the welding machine 1 is connected so as to supply a welding current to the welding torch 3 via the first power cable 5a and to the workpiece 10 via the second power cable 5b. The wire feeding device 2 includes a wire reel 2 a and supplies a welding wire 6 to the welding torch 3.

The shield gas supply device 4a further includes two shield gas supply sources, that is, one mixed gas cylinder 41a filled with a mixed gas of carbon dioxide gas and argon gas having good welding performance at a high pressure, and One carbon dioxide gas cylinder 41b filled with inexpensive carbon dioxide at a high pressure, one switching valve 44, a fourth connecting pipe 43a connecting the switching valve 44 and the two gas cylinders 41a, 41b, The first connecting pipe 45a, the sixth connecting pipe 43b, the seventh connecting pipe 45b, and the fourth connecting pipe 43a, the fifth connecting pipe 45a, the sixth connecting pipe 43b, and the seventh connecting pipe 45b. It is composed of a regulator 42a and a second regulator 42b. The switching valve 44 is provided with one outlet and two inlets like a three-way switching valve, and the outlets are individually communicated with each inlet by switching operation. When the communication state is switched, the outflow port and the two inflow ports are in communication at the same time on the way.

A case where welding is performed by the welding device configured as described above will be described below. To start welding, first, the switching valve 44 connects the first connecting pipe 7a and the fifth connecting pipe 45a to each other, and a stop valve (not shown) of the mixed gas cylinder 41a is opened to supply the mixed gas. The mixed gas flows from the mixed gas cylinder 41a to the welding torch 3 through the fourth connecting pipe 43a, the first regulator 42a, the fifth connecting pipe 45a, the switching valve 44, the first connecting pipe 7a, the welding machine 1 and the second connecting pipe 7b. It is supplied and discharged from the tip of the welding torch 3 to the weld. The supply amount of the mixed gas is adjusted to a predetermined supply amount by operating the first regulator 42a. Next, the welding machine 1 is operated to start supplying the welding current to the welding torch 3 and the workpiece 10 via the first power cable 5a and the second power cable, and at the same time, the wire feeding device 2 to the welding torch 3 The supply of the welding wire 6 wound on the reel 2a is started, and the welding of the workpiece 10 is started. The control function of the welding machine 1 corresponds to the welding condition of the workpiece 10 and sets and adjusts the feeding speed of the welding wire 6 supplied from the wire feeding device 2, the supply amount of the mixed gas and the welding current. It Even when the welding arc formation conditions started in this way are unstable, the penetration is sufficient and the bead shape is good because the shielding gas is a mixed gas with good welding performance. The amount of spatter is small and good welding can be performed.

After the welding is started as described above, the switching valve 44 is operated to switch the shield gas from the mixed gas to the carbon dioxide gas when the conditions for forming the arc and the state of the formed arc are stable. That is, a stop valve (not shown) of the carbon dioxide gas cylinder 41b is opened to supply carbon dioxide gas. The regulator 42b is set to a predetermined supply amount, the switching valve 44 is operated, and the shield gas supplied to the connection pipe 7a is switched from the mixed gas to the carbon dioxide gas. At the time of switching, the switching valve is designed so that the supply amount of carbon dioxide gas gradually increases and the supply amount of mixed gas gradually decreases, and the mixed gas and carbon dioxide gas are mixed and supplied while changing the mixing ratio. The switching operation of 44 is performed. Due to this switching operation, the composition of the shield gas gradually changes from the mixed gas to the carbon dioxide gas in the welded part of the object to be welded 10, and the sudden change in the properties of the shield gas, the pressure fluctuation or the pulsation due to the switching does not occur. , Good welding condition is maintained. When the switching operation of the switching valve 44 is completed, the first connecting pipe 7a and the seventh connecting pipe 45b communicate with each other in a normal state, and the first connecting pipe 7a and the fifth connecting pipe 45a are shut off. Then, the stop valve of the mixed gas cylinder 41a is closed. After that, welding is continued in this state using carbon dioxide gas as a shield gas.

In the above description, the case where a mixed gas of carbon dioxide gas and argon gas and carbon dioxide gas are used as the two types of shield gas has been described, but the technique of the present invention is not limited to these. For example, when using carbon dioxide mixed with oxygen gas, mixed carbon monoxide gas, mixed argon gas and oxygen gas, or using argon gas, helium gas, etc. (inert gas) as the shield gas. It is also applicable in the same manner, and the shield gas supply device is provided with three types and four types of shield gas, and it is also possible to appropriately select and switch the shield gas according to the material of the workpiece 10 or welding conditions. At this time, the switching valve 44 has one outlet and at least three inlets, and the outlet is individually communicated with each inlet by the switching operation, and when switching the communication state. The outlet and the optional two inlets can be connected at the same time. For example, one opening of each of three or more stop valves is connected as one outlet, the other opening is independent, and any two stop valves are independent while adjusting the opening. It is possible to operate by opening and closing (while shutting off other stop valves during this period).

Further, although the operation of the switching valve has been described in the manual state, it is a technique that can be automated and is also a technique that can be applied to a semi-automatic welding device or a full-automatic welding device. Furthermore, the technique of the present invention is not limited to the welding of steel materials, but is also applied to metal materials other than steel materials on which arc welding using shielded gas is performed.

[0018]

[Effect of device]

 The welding method and welding apparatus for arc welding using the shield gas according to the present invention are configured as described above, so that the following effects can be obtained. That is, a welding gas with good welding performance is supplied at the time of welding start, and when the arc formation state stabilizes, another type of shielding gas is supplied to switch to another welding gas. Supplying an expensive shield gas with good welding performance only for a short period of time, and then supplying an inexpensive shield gas with good welding performance to ensure good welding performance from the start of welding The cost of shield gas can be reduced.

For example, when welding a steel material, by supplying a mixed gas at the start of welding and then supplying carbon dioxide gas, the penetration is sufficient from the start of welding, the bead shape is good, and spatter is generated. The amount is small, and good welding performance that does not cause welding defects can be achieved at low cost.

Further, when the shield gas at the start of welding is switched to another type of shield gas, the shield gas is gradually supplied while simultaneously supplying both shield gases. No fluctuations or pulsations occur and good welding conditions are maintained.

The welding apparatus according to the present invention has a plurality of shield gas supply sources connected to a switching valve capable of selectively switching the gas supply sources so that the shield gas is supplied by operating the switching valve. It is possible to easily switch from one type to another.

In addition, the switching valve gradually switches two types of shield gas by connecting two inflow ports and an outflow port which are switched at the same time during the switching operation to gradually switch two types of shield gas. Smooth switching is possible without generating sudden changes in properties, pressure fluctuations, or pulsation.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a welding apparatus for arc welding using a shielding gas according to the present invention.

FIG. 2 is an overall configuration diagram showing a welding device for arc welding using a conventional shield gas.

[Explanation of symbols]

 1 Welder 2 Wire feeder 3 Welding torch 4 Shield gas supply device 4a Shield gas supply device 5a Power cable 5b Power cable 6 Welding wire 7a Connection pipe 7b Connection pipe 10 Welding object 41 Gas cylinder (shield gas supply source) 41a Gas cylinder (Shield gas supply source) 41b Gas cylinder (shield gas supply source) 42 Regulator 42a Regulator 42b Regulator 43 Connection pipe 43a Connection pipe 43b Connection pipe 44 Switching valve 45a Connection pipe 45b Connection pipe

Claims (2)

[Scope of utility model registration request] 1. A shield gas comprising a welding machine (1) having a control function, a wire feeding device (2), a welding torch (3) and a shield gas supply device (4a) is used. In the welding apparatus for arc welding, the shield gas supply device (4a) can selectively switch between at least two types of shield gas supply sources (41a, 41b) and at least two types of shield gas supply sources (41a, 41b). And a switching valve (44). 2. The switching valve (44) switches at least two inflow ports and the outflow ports to communicate with each other, and while switching the communication state between the outflow ports and any two inflow ports. The welding device according to claim 1, wherein the outflow port and the arbitrary two inflow ports are communicated at the same time.