Abstract: This laser beam processing apparatus includes a fiber laser oscillator, a laser beam branching unit, a laser beam injecting unit, a fiber transmission system, a laser beam irradiating unit, and a processing table. Based on a fiber laser beam, which is oscillation-outputted from the fiber laser oscillator, the laser beam branching unit executes simultaneous multi-branching from the fiber laser beam into a plurality of branched laser beams. The laser beam injecting unit injects the branched laser beams respectively into optical fibers for transmission and the laser beam irradiating units condense and apply the branched laser beams from the optical fibers for transmission respectively to processing points.

Abstract: A fiber laser beam processing apparatus is configured by a fiber laser oscillator, a laser power source unit, a laser beam injecting unit, a fiber transmission system, a laser beam irradiating unit, a processing table, etc. A portion of a fiber laser beam oscillated and outputted by the fiber laser oscillator is received by a photo diode for monitoring the power through a beam splitter. An output signal of the photo diode is sent to a laser power source unit. The power source unit receives the output signal of the photo diode as a feedback signal and controls a driving current or an excitation current to be supplied to a laser diode of a pumping unit such that the laser output of the fiber laser beam equals a set value.

Abstract: The fiber laser beam processing apparatus includes a fiber laser oscillator, a laser power source unit, a laser injecting unit, a fiber transmission system, a laser beam irradiating unit, a processing table, etc. The fiber laser oscillator includes an optical fiber for oscillation, an electric optical pumping unit that applies an excitation beam for optical pumping onto an end face of the optical fiber for oscillation, and a pair of optical resonator mirrors optically facing each other through the optical fiber for oscillation. The optical fiber for oscillation includes a core extending on the central axis thereof, a clad surrounding the core, an air layer surrounding the clad, and a support surrounding and supporting the air layer.

Abstract: An end cap is formed as a substantially cylindrical body having substantially the same diameter as an external diameter of a retaining unit of an oscillation fiber; a base end surface is integrally fusion-welded or fusion-bonded to one end surface of the oscillation fiber; and a leading end surface is obliquely cut relative to the light axis. A returning oscillating beam reflected by an optical resonator mirror is converged and made incident on a core end surface of the oscillation fiber 22 located at a focus position of an optical lens. However, since the core end surface is integrally bonded with the end cap and is not exposed to the atmosphere, the core end surface is not burned or deteriorated by the light energy of the oscillating beam.

Abstract: A KTP crystal is irradiated by a long-pulse fundamental wave pulse laser beam having a pulse width of 100 ?s or longer typically output from a solid-state pulse laser such as a YAG pulse laser. In the KTP crystal, wavelength conversion is performed to generate a second harmonic pulse laser beam with a two times higher frequency, which long-pulse second harmonic pulse laser beam is in turn output for laser processing such as welding etc.

Abstract: A laser welding process of the present invention comprises the steps of allowing a laser beam outputted from a laser beam generator to enter into an optical fiber through a light-introducing optical unit, and applying the laser beam exiting from the optical fiber to a weld zone through a light-delivering optical unit. The laser welding process is characterized in that the optical fiber has a core diameter set to be within 100 ?m, a numeral aperture value for entrance of light into the optical fiber is set to be equal to or smaller than 0.05, a numeral aperture value for exiting of light from the optical fiber is set to be equal to or smaller than 0.1, and an energy of a one-pulse laser beam applied from the light-delivering optical unit is set at a value equal to or smaller than 1 joule.

Abstract: A laser weld monitoring system capable of assessing a weld quality of welding using a pulsed laser is provided. The system includes at least one sensor capable of capturing a weld characteristic of welding using said pulsed laser. The weld characteristic has multiple attributes. The system also includes data acquisition and processing equipment adapted for storing and analyzing the weld characteristic. A user first performs multiple welds to capture at least one weld characteristic for each weld. The user then determines the weld quality of each weld, and runs at least one of a library of algorithms associated with the attributes on said at least one weld characteristic for each weld to generate a single value output for the associated attribute. The user selects an attribute indicative of the weld quality by correlating the single value outputs of said at least one algorithm with the weld qualities of the welds.

Abstract: A laser weld monitoring system capable of assessing a weld quality of welding using a pulsed laser is provided. The system includes at least one sensor capable of capturing a weld characteristic of welding using said pulsed laser. The weld characteristic has multiple attributes. The system also includes data acquisition and processing equipment adapted for storing and analyzing the weld characteristic. A user first performs multiple welds to capture at least one weld characteristic for each weld. The user then determines the weld quality of each weld, and runs at least one of a library of algorithms associated with the attributes on said at least one weld characteristic for each weld to generate a single value output for the associated attribute. The user selects an attribute indicative of the weld quality by correlating the single value outputs of said at least one algorithm with the weld qualities of the welds.

Abstract: In each odd-numbered unit current-supplying period of a plurality of unit current-supplying periods making up a set current-supplying time, a control unit subjects only positive switching elements to continuous switching operations at an inverter frequency while keeping negative switching elements in an OFF state, whereas in each even-numbered unit current-supplying period, the control unit subjects only the negative switching elements to continuous switching operations while keeping the positive switching elements in an OFF state. This allows a secondary current having a substantially trapezoidal current waveform to flow through a secondary circuit of a power supply apparatus in the positive direction in each odd-numbered unit current-supplying period but in the negative direction in each even-numbered unit current-supplying period.

Abstract: In odd-numbered current-supplying periods of a plurality of current-supplying periods constituting a gross current-supplying time, a control unit 42 allows continuous switching actions of only a first set of switching elements at an inverter frequency, with a second set of switching elements remaining OFF. In even-numbered current-supplying periods, the control unit 42 allows continuous switching actions of only the second set of switching elements at the inverter frequency, with the first set of switching elements (24, 28) remaining OFF. As a result of this, a secondary circuit of the power supply apparatus allows a secondary current i2, namely a fusing current I having a substantially trapezoidal current waveform to flow in a positive direction in the odd-numbered current-supplying periods, and to flow in a negative direction in the even-numbered current-supplying periods.

Abstract: Disclosed is a resistance welding power supply apparatus which comprises a large-capacitance capacitor for storing resistance welding energy in the form of electric charges, a charging circuit for charging the capacitor to a predetermined voltage, four switching elements or means electrically connected between the capacitor and a pair of welding electrodes, and a control unit for allowing selective switching operations of the switching elements during a weld time to provide a control of welding current. Diodes are connected in parallel with the switching elements, respectively, with current polarities opposite thereto. The control unit terminates a switching pause period for polarity switching in a very brief time and initiates a switching control in the next current-supplying mode in the middle of fall of the welding current.

Abstract: A resistance welding power supply apparatus comprises a large-capacitance capacitor for storing resistance welding energy, a capacitor charging circuit, a switching element electrically connected between the capacitor and one electrode of a pair of welding electrodes, and a control unit for the switching element. If the welding current is less than a set current value at a point of time on the leading edge of a clock, then the control unit holds a control pulse for the switching element active or high from that point of time till the time when the welding current exceeds the set current value without being affected by the cycle of the clock. If the welding current exceeds the set current value at a point of time on the leading edge of the clock, then the control unit holds the control pulse inactive or low till a point of time on the leading edge of the next clock.

Abstract: This reflow soldering apparatus comprises a heater tip 10 for soldering sites to be soldered of a workpiece W by reflow method, a power supply unit for supplying an electric power for heat generation or heating to the heater tip, a control unit for providing a control of the supplied current in the power supply unit, and a pressing unit 16 for pressing the heater tip against the sites to be soldered of the workpiece W. An inverter of the power supply unit has four transistor switching elements. By the control unit by way of a driving circuit, the first set of switching elements and are simultaneously switching (ON/OFF) controlled at a predetermined inverter frequency (e.g., 10 kHz) in response to in-phase inverter control signals G1 and G3, whereas the second set of switching elements are simultaneously switching controlled at the inverter frequency in response to in-phase inverter control signals G2 and G4.

Abstract: On a “schedule” screen appearing on a display the user performs desired set value entries or action instructions on the apparatus by means of key entries. In order to set and enter a reference waveform for waveform control in particular, desired numerical value data are set and entered into items of a laser output reference value PEAK and waveform elements ↑ SLOPE, FLASH1, FLASH2, FLASH3 and ↓ SLOPE. Within the interior of the apparatus the reference waveform for waveform control and a reference waveform graph for display are obtained on the basis of the entered set values of the waveform element items. The reference waveform for waveform control is used as a reference value for the waveform control in the laser output waveform control. The reference waveform graph for display appears in a predetermined area on the screen in response to a predetermined key action.

Abstract: In a power monitor mode, during the laser oscillation output there are fetched laser output measured values, lamp voltage measured values and lamp current measured values (step J1), and energy of each pulse is figured out on the basis of time integral value of the laser output measured values (step J2). Then, at a certain time Ta interval, an energy average value and a laser output average value are figured out for display based on the cumulative value of the energy of each pulse, and a lamp power average value QM and a lamp power input ratio KM are found by calculation from the cumulative value of the lamp power (SV·SI) of each pulse (step J5). In OFF display mode the lamp power input ratio KM appears. Under the laser output feedback control, the lamp power input ratio KM gradually goes up according as the deterioration with time increases within a laser oscillation unit.

Abstract: A simmer circuit 18 comprises a power supply unit 54 for the supply of a simmer current Is to an excitation lamp 22 and a control unit 56 for the control of the current value of the simmer current Is. In the control unit 56, a current detection signal Vs from a current sensor, e.g., a Hall CT 70 attached to the power supply unit 54 is fed via a buffer amplifier 72 for impedance conversion to a non-inversion input terminal of an operational amplifier 82 for signal amplification. The amplification factor &mgr; of the operational amplifier 82 differs depending on which one is selected from three switches 84, 86 and 88. A CPU 38 selects the switch 84 when switching the simmer current Is to 0.3 A for “low speed zone”, selects the switch 86 when switching to 2 A for “medium speed zone” and switches 88 when switching to 5 A for “high speed zone”.

Abstract: After the initiation of a first current-supplying time an insulator of a coated wired W1 cuts off an electrically conductive path and hence a secondary current I2 for melting and removing the insulator is caused to flow from an upper electrode 20 by way of an intermediate electrode 26. An interior conductor is exposed to form an electrically conductive path leading to workpieces (W1 and W2) between the upper electrode 20 and a lower electrode 22, allowing a branch current IB to flow into the lower electrode 22. A control unit monitors a current detection signal <IB> from a current detecting circuit 34. When the signal <IB> has reached a skip level SK, the control unit terminates the supply of current of a first current-supplying time and initiates the current supply of a second current-supplying time for joining the wire W1 to a terminal member W2.

Abstract: The number of cycles R of a fundamental frequency <SET>F (Hz) for a set value Tw (ms) of a set weld time [WELD] is first found as a real number. The number of cycles R conforms to the number of times (real number) of repetition of the fundamental frequency <SET>F cycle in the interval of the set weld time Tw and is given as Tw×<SET>F (step B1). An AC waveform cycle set value Ns (integer) for the set weld time Tw is then determined as an integer Min [N] that is equal to the number of cycles R or to the least one (i.e., the integer closest to R) of larger integers (N) than R (step B2). An AC waveform cycle set frequency Fs (Hz) and a period Ts (ms) for the set weld time Tw is then found from the set number of cycles Ns. The set frequency Fs and the period Ts are given as Fs=1/Ts and Ts=Tw/Ns, respectively (step B3).

Abstract: Disclosed is a resistance-welding power supply apparatus comprising a large-capacitance capacitor for storing a welding energy in the form of electric charge, a charging unit for charging the capacitor up to a predetermined voltage, a transistor group electrically connected between the capacitor and a welding electrode on one hand, and a control unit for causing a switching action of the transistor group at a predetermined frequency during the weld time to provide a control of a welding current I. The charging unit includes a charging transformer and a rectifying circuit. The control unit includes a main control unit for providing a control of the switching action of the transistor group by way of a drive circuit. The control unit further includes various sensors, measuring circuits and an arithmetic circuit, for providing a feedback control of the welding current, an interelectrode voltage or a welding power.

Abstract: A laser processing apparatus in which a laser beam oscillatory output from a laser oscillation unit is transmitted through an optical fiber to a remote laser processing site, where the laser processing apparatus has an optical fiber setting apparatus for finding a supply power upper limit for the type of fiber (including a step index (SI) fiber and a graded index (GI) fiber) used and the diameter of the optical fiber, and a laser power supply unit for supplying the laser oscillation unit with an electric power for laser oscillation. A supply power mean value arithmetic apparatus detects the electric power supplied to the laser oscillation unit to figure out a supply power mean value at a certain interval, and the laser power supply unit is interrupted when the supply power mean value exceeds the supply power upper limit.