Abstract: In an arc start control method for forward and reverse feed arc welding in which forward and reverse feed control of alternately switching a feed speed Fw of a welding wire between a forward feed period and a reverse feed period is performed to generate a short circuit period and an arc period to perform welding, at arc start, a pulse period Tp during which a pulse current is energized for a plurality of number of times is provided, and thereafter forward and reverse feed control is started from forward feed period of the welding wire. During the pulse period Tp, a forward feed speed Fp of the welding wire is set so that the arc period is continuous. In addition, the forward feed speed Fp is changed based on a time length of pulse period Tp and/or a value of a welding voltage Vw during pulse period Tp.

Abstract: An impedance matching device comprises a variable capacitor including multiple capacitance elements and connected in parallel having capacitors and each having one end connected in series to a high-frequency power source and semiconductor switches and connected to the respective capacitors, and a control unit. The control unit derives a reflection coefficient based on the obtained information concerning an impedance viewed from the high-frequency power source toward the load side, updates the states of the respective semiconductor switches and included in the multiple capacitance elements and with a first cycle in the case where the reflection coefficient is equal to or more than a predetermined value, and updates the states of the respective semiconductor switches and included in the plurality of capacitance elements and with a second cycle longer than the first cycle in the case where the reflection coefficient is less than the predetermined value.

Abstract: Proposed are techniques for suppressing an increase in a reflected wave power Pr (synonymous with a reflection coefficient) due to IMD. A high-frequency power supply system for providing a high-frequency power to a connected load includes: a bias power supply that outputs a bias power at a first frequency; a source power supply that outputs a source power at a second frequency higher than the first frequency; and a matching unit including an impedance matching circuit that acquires the bias power and the source power, and provides matching between an impedance on the source power supply side and an impedance on the load side. The source power supply supplies the bias power supply with a sinusoidal synchronizing signal including information about an output frequency to be outputted by the bias power supply, and the bias power supply outputs the bias power of a frequency corresponding to the output frequency included in the sinusoidal synchronizing signal.

Abstract: A driving apparatus has a problem in that foreign matter, such as grease, in a reduction gear moves from the reduction gear to a coupling side. Therefore, a driving apparatus includes an input shaft with a hollow space, a motor that rotates the input shaft, a reduction gear that receives the power of the motor from the input shaft, an output shaft inserted through the hollow space of the input shaft and adapted to rotate about the rotation axis of the motor, and a coupling connected to a tip end of the output shaft. A first limiting member for limiting the movement of foreign matter in the reduction gear toward the coupling side is arranged between the reduction gear and the coupling.

Abstract: An object is to provide a power system interconnection system and a method of installing the power system interconnection system that are able to supply a load with required power. A power system interconnection system comprises a storage battery an AC-DC power conversion device for the storage battery a charge and discharge station for an electric-powered automobile and an interconnection control device that are installed on a parking lot. The interconnection control device supplies a first load with power from at least one of the charge and discharge station and the AC-DC power conversion device in a case where the electric power system is in an emergency situation.

Abstract: A wire feeding system includes a first feeder provided with a first feeding motor that feeds a wire in a wire feeding direction, a second feeder spaced apart from the first feeder in the wire feeding direction and provided with a second feeding motor that feeds the wire in the wire feeding direction, and a controller that controls the rotation speed of the first feeding motor based on a first speed command and controls the rotation speed of the second feeding motor based on a second speed command. The controller gradually changes the second speed command over time when an amount of change of the second speed command is not within a predetermined range.

Abstract: A high-frequency power supply circuit includes an amplifier circuit. In the amplifier circuit, one end of an inductor is connected to a direct-current power supply. One end of a switching element is connected to the other end of the inductor. A parallel capacitor is connected in parallel to the switching element. One end of an LC series circuit is connected to the one end of the switching element. A circuit capacitor is connected between the other end of the LC series circuit and the other end of the switching element. The amplifier circuit amplifies a signal having a unique frequency input to a control terminal of the switching element. The amplifier circuit outputs, to a load, a current having the frequency from a connection point between the other end of the LC series circuit and the circuit capacitor.

Abstract: A non-consumable electrode arc-welding method is provided for causing a welding machine to output or stop a welding current in accordance with at least an ON state and an OFF state of a start signal. In the method, a start signal is switched between an ON state and an OFF state, thereby controlling the on/off operation of the welding machine. Further, an operation mode instruction signal is switched between a normal mode and an interval mode, thereby controlling the operation mode of the welding machine. When the operation mode instruction signal indicates the interval mode and also the start signal is in the ON state, the welding current is outputted in a welding current output period. Then, the output of the welding current is suspended in a welding current interval period successively following the welding current output period.

Abstract: In an arc welding control method for controlling welding in which a material of a base material is a galvanized steel sheet, a feed speed of a welding wire is alternately switched between a forward feed period and a reverse feed period, and a short circuit period and an arc period are repeated, during the arc period, a first arc period Ta1 during which a first arc current Ia1 is applied, a second arc period Ta2 during which a second arc current Ia2 is applied, and a third arc period Ta3 during which a third arc current Ia3 is applied are switched over time, and it is controlled so as to be Ia1>Ia2>Ia3. Constant voltage control is performed during the second arc period Ta2, and constant current control is performed during the first arc period Ta1.

Abstract: Techniques for suppressing an increase in reflected wave power (reflection coefficient) due to IMD are proposed. A high-frequency power supply system for providing a high-frequency power to a connected load includes: a bias power supply which outputs a bias power at a first frequency; a source power supply which outputs a source power at a second frequency higher than the first frequency; and a matching unit including an impedance matching circuit which acquires the bias power and the source power and matches an impedance of the source power supply side with an impedance of the load side. The source power supply determines a delay setting value indicating the timing of starting a frequency variation process with respect to the source power, performs the frequency variation process using the delay setting value and the value of the first frequency, and outputs a frequency-varied source power to the matching unit.

Abstract: An arc start adjustment device adjusting an arc start procedure in a welding process comprises an obtainment unit that obtains welding data indicating a welding state during or after a welding process, and a procedure adjustment unit that adjusts the arc start procedure such that the cycle time of the welding process is shortened based on welding data obtained by the obtainment unit.

Abstract: An impedance matching device includes: a variable capacitor in which a plurality of series circuits of capacitors and semiconductor switches are connected in parallel; a calculation unit that calculates an impedance or a reflection coefficient on the load side using information regarding impedance acquired from the outside; and a control unit that determines ON/OFF states to be taken by the semiconductor switches included in the variable capacitor using the impedance or the reflection coefficient calculated by the calculation unit and turns on or off the semiconductor switches based on the determined states. The control unit changes an ON/OFF control timing between one and another of the semiconductor switches.

Abstract: Provided is a welding position detection device capable of improving the welding position detection accuracy. The welding position detection device includes a calculation unit that irradiates two members to be joined with laser light to calculate approximate straight lines of the respective members, calculates an end portion of one member of the two members on the basis of the approximate straight line of the one member, and calculates a virtual straight line which is a straight line connecting the calculated end portion of the one member and the approximate straight line of the other member of the two members and having a specific angle with respect to the approximate straight line of the one member, and a detection unit that detects an intersection point of the calculated virtual straight line and the approximate straight line of the other member as a welding position.

Abstract: There is provided an arc welding method. In the method, welding is performed in a spray transfer mode by feeding a welding wire. A first welding current Iw1 is flown during a first period. A second welding current Iw2 is flown during a second period. A third welding current Iw3 is flown during a third period, where 0<Iw2<Iw3<Iw1. The first to third periods are alternately repeated.

Abstract: A multi-level hand apparatus includes a plurality of hands arranged to overlap with each other as viewed in a vertical direction, and each hand includes a hand body and a support body that supports the hand body at a base portion of the hand body. The multi-level hand apparatus further includes a guide for allowing and guiding movement of the hands in the vertical direction while maintaining the orientations of the hands, and a hand pitch limiter for defining a maximum pitch of the hands. The hands are divided into two groups, i.e., the first-group hands located at every other position and the second-group hands other than the first-group hands. The hand pitch limiter defines the maximum pitch between pairs of a first-group hand and a second-group hand that are vertically adjacent to each other.

Abstract: An impedance matching device 1 includes multiple capacitance elements and a control unit that controls on or off of semiconductor switches. The capacitance elements and respectively include a first capacitance element group and a second capacitance element group. The control unit updates the state of the first semiconductor switch included in the first capacitance element group with a first cycle until a predetermined time period elapses during which the state of the first semiconductor switch included in the first capacitance element group is maintained while the control unit updates the states of the semiconductor switch and respectively included in the first capacitance element group and the second capacitance element group with a second cycle longer than the first cycle after the predetermined time period elapses during which the state of the first semiconductor switch included in the first capacitance element group is maintained.

Abstract: The wire feeding device that feeds welding wire W from the wire source to the welding torch is disposed between the wire source and the welding torch and is configured to temporarily accommodate the welding wire W fed from the wire source and to feed the accommodated welding wire W to the welding torch. In the case where feeding of welding wire W is abnormally stopped, if the acceptance unit accepts instructions for increasing or decreasing, the wire feeding device controls the speed of feeding welding wire W fed by the first feeding part or the second feeding part so that a difference is generated in the feeding speed of the first feeding part and the second feeding part and the accommodated amount of welding wire W is in a range from the lower limit of normal to an upper limit of normal.

Abstract: An impedance matching device includes: a variable capacitor; a calculation unit that calculates a reflection coefficient on the load side; a storage unit that stores the reflection coefficient calculated within a predetermined period so as to be associated with ON/OFF states of the semiconductor switches; a determination unit that determines ON/OFF states to be taken by the semiconductor switches using a calculation result within the predetermined period; a control unit that turns on or off the semiconductor switches based on the determined ON/OFF states; and a counting unit that counts the number of times the determined ON/OFF states have changed. In a case where the counted number of times is larger than a predetermined number of times, the control unit turns on or off the semiconductor switches so as to match ON/OFF states associated with a reflection coefficient closer to 0, among the stored reflection coefficients, and then prohibits ON/OFF switching.

Abstract: A drive circuit performs switching between an on-state and an off-state of a PIN diode, the drive circuit being provided with a switching element and a switching element, a drive power supply, and a current limiting resistor that adjusts a forward current of the PIN diode. When the switching element is in an on-state and the switching element is in an off-state, the PIN diode is switched to the on-state by applying a forward voltage to the PIN diode from the drive power supply via the current limiting resistor, and when the switching element is in the off-state and the switching element is in the on-state, the PIN diode is switched to the off-state by applying, not via the current limiting resistor, a reverse voltage to the PIN diode from the drive power supply.

Abstract: A metal powder for additive manufacturing includes: not less than 0.2 mass % and not more than 1.3 mass % of aluminum; and a balance including copper and an incidental impurity.