Abstract: A step-down type DC—DC power-supply device implements both the stabilization of the control loop and the responsibility at the same time. In the power-supply device, an output power signal is fed back to an error amplifier after having passed through a CR smoothing filter provided independently of a power LC smoothing filter. Also, independently of the duty controls over Power MOSFETs, i.e., upper-side/lower-side semiconductor switching components in the steady state, an output from the power LC smoothing filter is added to an upper and lower limit-mode-equipped control circuit, thereby, at the transient state, forcefully setting the duty &agr; at either 0% or 100%.

Abstract: The present invention provides a non-cyanide displacement gold plating solution with which even an electroless nickel-boron plated or electrolytic nickel plated substrate can be subjected to displacement gold plating with good adhesion properties and high solderability. The displacement gold plating solution in accordance with the present invention contains 0.01 to 1.0 g/L (expressed in terms of gold concentration) of sodium gold sulfite or ethylene diamine complex of sodium gold sulfite, 10 to 100 g/L of sulfite, 5 to 50 g/L of organic carboxylic acid or salt thereof, and 5 to 50 g/L of ethylene diamine tetraacetic acid or salt thereof, and has a pH value in the weak acid range of 4.5 to 6.

Abstract: A step-down type DC-DC power-supply device implements both the stabilization of the control loop and the responsibility at the same time. In the power-supply device, an output power signal is fed back to an error amplifier after having passed through a CR smoothing filter provided independently of a power LC smoothing filter. Also, independently of the duty controls over Power MOSFETs, i.e., upper-side/lower-side semiconductor switching components in the steady state, an output from the power LC smoothing filter is added to an upper and lower limit-mode-equipped control circuit, thereby, at the transient state, forcefully setting the duty &agr; at either 0% or 100%.

Abstract: A DC power supply device comprises an AC/DC converter 1, a DC/DC converter 2, and a DC converter 3 converting DC power from a battery 4 to DC voltage for connecting to output terminals of the AC/DC converter. The DC power supply device is provided with a controlling circuit 100 which observes a charging control level and a load sharing level, impresses a charging command on a UPS controlling part controlling the DC converter, and simultaneously provides a PFC controlling part controlling the AC/DC converter with a current command when a voltage level is less than the charging control level, stops only the charging command when the voltage level is more than the charging level and less than the load sharing level, and provides the UPS controlling part and the PFC controlling part with current commands when the voltage level is more than the load sharing level.

Abstract: A DC power supply device comprises an AC/DC converter 1, a DC/DC converter 2, and a DC converter 3 converting DC power from a battery 4 to DC voltage for connecting to output terminals of the AC/DC converter. The DC power supply device is provided with a controlling circuit 100 which observes a charging control level and a load sharing level, impresses a charging command on a UPS controlling part controlling the DC converter, and simultaneously provides a PFC controlling part controlling the AC/DC converter with a current command when a voltage level is less than the charging control level, stops only the charging command when the voltage level is more than the charging level and less than the load sharing level, and provides the UPS controlling part and the PFC controlling part with current commands when the voltage level is more than the load sharing level.

Abstract: The present invention provides a non-cyanide displacement gold plating solution with which even an electroless nickel-boron plated or electrolytic nickel plated substrate can be subjected to displacement gold plating with good adhesion properties and high solderability. The displacement gold plating solution in accordance with the present invention contains 0.01 to 1.0 g/L (expressed in terms of gold concentration) of sodium gold sulfite or ethylene diamine complex of sodium gold sulfite, 10 to 100 g/L of sulfite, 5 to 50 g/L of organic carboxylic acid or salt thereof, and 5 to 50 g/L of ethylene diamine tetraacetic acid or salt thereof, and has a pH value in the weak acid range of 4.5 to 6.

Abstract: A DC power supply device comprises an AC/DC converter 1, a DC/DC converter 2, and a DC converter 3 converting DC power from a battery 4 to DC voltage for connecting to output terminals of the AC/DC converter. The DC power supply device is provided with a controlling circuit 100 which observes a charging control level and a load sharing level, impresses a charging command on a UPS controlling part controlling the DC converter, and simultaneously provides a PFC controlling part controlling the AC/DC converter with a current command when a voltage level is less than the charging control level, stops only the charging command when the voltage level is more than the charging level and less than the load sharing level, and provides the UPS controlling part and the PFC controlling part with current commands when the voltage level is more than the load sharing level.

Abstract: A direct-current power-supply apparatus provided by the present invention comprises a switching converter for converting an input direct-current power into another direct-current power, a control circuit and an isolation means. The switching converter has a main switch device for generating a pulse voltage from the direct-current input, a synchronous-rectification circuit on the output side of the switching converter and a reverse-current-blocking switch. On the other hand, the control circuit includes a PWM formation unit for driving the main switch device, a synchronous-rectification control unit for controlling an operation to drive the synchronous-rectification circuit and a driving control unit for controlling an operation to drive the reverse-current-blocking switch. The control circuit operates by using a common electric potential appearing on the output side of the switching converter as a reference electric potential. A driving signal is applied to the main switch device through the isolation means.

Abstract: A DC power supply device comprises an AC/DC converter 1, a DC/DC converter 2, and a DC converter 3 converting DC power from a battery 4 to DC voltage for connecting to output terminals of the AC/DC converter. The DC power supply device is provided with a controlling circuit 100 which observes a charging control level and a load sharing level, impresses a charging command on a UPS controlling part controlling the DC converter, and simultaneously provides a PFC controlling part controlling the AC/DC converter with a current command when a voltage level is less than the charging control level, stops only the charging command when the voltage level is more than the charging level and less than the load sharing level, and provides the UPS controlling part and the PFC controlling part with current commands when the voltage level is more than the load sharing level.

Abstract: A power supply apparatus includes a semiconductor switching device for outputting power and a control circuit for controlling the on/off operation of the semiconductor switching device. The control circuit includes a circuit for applying, when turning on the semiconductor switching device, a first control signal corresponding to the difference between the output voltage of the power supply apparatus and a first reference value to the semiconductor switching device in accordance with the increase in the output voltage from the power supply apparatus thereby to operate the semiconductor switching device in a non-saturated area, so that the semiconductor switching device is turned on gradually.

Abstract: A direct-current power-supply apparatus provided by the present invention comprises a switching converter for converting an input direct-current power into another direct-current power, a control circuit and an isolation means. The switching converter has a main switch device for generating a pulse voltage from the direct-current input, a synchronous-rectification circuit on the output side of the switching converter and a reverse-current-blocking switch. On the other hand, the control circuit includes a PWM formation unit for driving the main switch device, a synchronous-rectification control unit for controlling an operation to drive the synchronous-rectification circuit and a driving control unit for controlling an operation to drive the reverse-current-blocking switch. The control circuit operates by using a common electric potential appearing on the output side of the switching converter as a reference electric potential. A driving signal is applied to the main switch device through the isolation means.

Abstract: The invention relates to a power supply system having plural converters connected in parallel. The current of each of the plural converters is detected and each of the converters is controlled so as to match each of the converters to a maximum current value from among the detected current values. In the parallel converters, when one or more converter fails, having an output current of zero, the remaining converters are each partially charged equally to maintain the load current. Since a common bus is arranged between plural converters and plural loads, it is possible to carry out a redundant operation having a high reliability. Since a stable output can be obtained without being affected by the failed converter, a power supply system having the redundancy and the high reliability can be attained.

Abstract: An electric working apparatus includes a movable body which is driven by a movement mechanism, and the movable body is provided with a working mechanism such as an articulated robot. The movement mechanism, the working mechanism and etc. are driven by an electric power which is supplied through a power supply cord being extended from a cord reel mechanism fixed on a wall or floor within a working space of the movable body to be connected to the movable body. When the movable body moves in a manner that the movable body goes away from the cord reel mechanism, a tension detection switch is turned-off by a lever, a reel motor is turned-off, and clutch plates are released, and therefore, the power supply cord is wound from the cord reel mechanism by necessary length.

Abstract: A parallelized power supply system including a plurality of switching power supplies each having a circuit for limiting rush current generated when a main switch is turned on. This system can be installed in an apparatus which requires the functions such as power uninterrupted operation and live wire insertion/dismount. Each switching power supply has another power supply for driving the rush current limiter circuit and a relay circuit for supplying relay driving current and making a connection of relay contacts after a predetermined time lapse after the operation start of the switching power supply. An a.c. power is supplied via the relay contacts to each switching power supply. The relay driving time set in the rush current limiter circuit is different for each switching power supply.

Abstract: A method for forming a cup-shaped piston having a peg comprises a first preform step forming a first preform having a flat top surface and a recessed portion at its bottom, a second preform step forming therein a second preform having a projecting or recessed portion on the top surface of the end portion in order to readily form a peg, and a final step finishing the second preform to have the cup-shaped piston having the peg.