Abstract: In a method and device for performing welding, after the welding current reaches a first current value during a short circuit, the feeding of the welding wire is stopped, slowed down, or moved backward. As a result, the opening of a short circuit is urged to reduce the frequency at which welding is unnecessarily interrupted by an overcurrent protection function. This achieves high weld quality such as the absence of welding defects, and high production efficiency.

Abstract: A plurality of scaly beads is formed and arranged continuously on a base material in welding cycle C that is a sum of arc ON period A during which welding current I flows to a welding wire and arc OFF period B during which welding current I does not flow to the welding wire. This arc welding control method includes: an initial condition setting step of setting initial values of welding conditions for arc-welding the base material; and a scaly bead formation step of forming the plurality of scaly beads in a predetermined welding section of the base material while moving the welding wire at welding speed Vw in the predetermined welding section of the base material. The welding conditions include arc ON period A and arc OFF period B, and further include at least one of welding current I, welding speed Vw, and interval G of the beads.

Abstract: In a method and device for performing welding, after the welding current reaches a first current value during a short circuit, the feeding of the welding wire is stopped, slowed down, or moved backward. As a result, the opening of a short circuit is urged to reduce the frequency at which welding is unnecessarily interrupted by an overcurrent protection function. This achieves high weld quality such as the absence of welding defects, and high production efficiency.

Abstract: In a method and device for performing welding, after the welding current reaches a first current value during a short circuit, the feeding of the welding wire is stopped, slowed down, or moved backward. As a result, the opening of a short circuit is urged to reduce the frequency at which welding is unnecessarily interrupted by an overcurrent protection function. This achieves high weld quality such as the absence of welding defects, and high production efficiency.

Abstract: A welding control method alternately repeats a short circuit period, during which a welding wire and an object to be welded short-circuit, and an arc period, during which an arc is generated and discharged, to weld the object to be welded. The method compares average output voltage, which is an average of welding voltage calculated during welding, to set voltage preliminarily set, and controls a welding output current produced when an arc is generated based on the comparison result therefrom, to regulate the meltage of the wire for adjusting the arc length, which brings the short circuit cycle closer to a constant one when a disturbance (e.g. extended or shortened arc length) occurs.

Abstract: A welding control method for a welding device having an output characteristic with a predetermined gradient showing a relation between a welding output voltage and a welding output current. By setting a set target welding voltage that is higher than the set initial welding voltage according to a difference between the set initial welding voltage and the welding output voltage, the welding output voltage is controlled to be the set target welding voltage. Thus, a proper arc length can be achieved early by correcting the change of the arc length due to, for example, motion of the hands of a welding operator.

Abstract: In a method and device for performing welding, after the welding current reaches a first current value during a short circuit, the feeding of the welding wire is stopped, slowed down, or moved backward. As a result, the opening of a short circuit is urged to reduce the frequency at which welding is unnecessarily interrupted by an overcurrent protection function. This achieves high weld quality such as the absence of welding defects, and high production efficiency.

Abstract: A welding control method for a welding device having an output characteristic with a predetermined gradient showing a relation between a welding output voltage and a welding output current. By setting a set target welding voltage that is higher than the set initial welding voltage according to a difference between the set initial welding voltage and the welding output voltage, the welding output voltage is controlled to be the set target welding voltage. Thus, a proper arc length can be achieved early by correcting the change of the arc length due to, for example, motion of the hands of a welding operator.

Abstract: A welding control method alternately repeats a short circuit period, during which a welding wire and an object to be welded short-circuit, and an arc period, during which an arc is generated and discharged, to weld the object to be welded. The method compares average output voltage, which is an average of welding voltage calculated during welding, to set voltage preliminarily set, and controls a welding output current produced when an arc is generated based on the comparison result therefrom, to regulate the meltage of the wire for adjusting the arc length, which brings the short circuit cycle closer to a constant one when a disturbance (e.g. extended or shortened arc length) occurs.

Abstract: There are provided an operating mechanism that drives the opening/closing of contacts, and a sliding conduction part that forms electrical connection of these contacts and the main circuit on receipt of a connection voltage; grease is applied to the mechanical sliding part of the operating mechanism and to the sliding conduction part. The grease has as base oil at least one synthetic oil and is selected from the group consisting of poly &agr;-olefins and dialkyl diphenyl ethers, and contains as thickener 5-30 mass % of a urea compound. The dynamic viscosity of the base oil is 30-500 mm2/s at 40° C.

Abstract: In a closing magnetic circuit, when a movable contact is in contact with a fixed contact and a switching device is closed, N and S poles of a permanent magnet attract the fixed member in a direction in which the movable contact is pressed against the fixed contact. In an opening magnetic circuit, when the movable contact is separated from the fixed contact and the switching device is open, one of the N and S poles of the permanent magnet attracts the fixed member in a direction in which the movable contact is separated from the fixed contact. An operating electromagnet winding increases and decreases the magnetism in the closing magnetic circuit and opening magnetic circuit. With this configuration, it is possible to realize an operating apparatus for a switching device using a simple mechanism and assure a stable operation by producing a great contact load.