Abstract: Provided is a cool air flow space in which cool air, that is generated by an inner fan disposed inside a housing, flows in the housing. An attachment member mounts a magnetic component on a bottom portion of the housing at a position within the cool air flow space. The attachment member includes a top plate and a pair of legs that extends downward from the top plate and that is fixed to the bottom portion.

Abstract: An electronic equipment cooling device is provided, which has housing in which heat-generating components are housed, and which can cool surfaces of the housing. A blower fan blows air toward the surfaces via a chamber room. An inclined flat plate-like partition portion is provided inside the chamber room so as to distribute a desired amount of air corresponding to a heat generating ratio of the respective surfaces.

Abstract: A cooling device includes a plurality of side wall fins formed on an outer surface of a first side wall of a housing, and a plurality of bottom fins formed on a bottom surface of a bottom portion of the housing. A cover member covers the side wall fins and bottom fins from an outer side to form side wall and bottom cooling channels. A chamber is provided that forms a fluid introduction chamber in a direction facing a second side wall so as to communicate with the side wall cooling channel and the bottom cooling channel. A coolant supply device is externally attached to the chamber so as to supply a coolant to the fluid introduction chamber. The side wall fins and the bottom fins are formed in predetermined shapes to adjust an amount of the coolant in the side wall cooling channel and the bottom cooling channel.

Abstract: A flyback type switching power supply includes between P and N of a direct current output a sudden load change detector circuit, which normally has no power consumption, that detects only a transient fluctuation of a direct current output voltage, and starts the switching of a primary side semiconductor switch when there is no load or a light load, even when the semiconductor switch is in an off state, thereby enabling the detection of the direct current output voltage in a tertiary winding, and suppressing a drop in the direct current output voltage.

Abstract: A control device is configured to, when the direct current output voltage of a resonant DC-DC converter is of a value that exceeds the maximum value that can be output in a fixed frequency control region, there is a switch from fixed frequency control to frequency modulation control. Because of this, conduction loss and turn-off loss caused by backflow current among semiconductor switching elements of the resonant DC-DC converter are reduced, power conversion efficiency is improved, and the range of voltage that can be output by the resonant DC-DC converter is expanded.

Abstract: A switching power supply device and method for control thereof, including an input voltage generating unit, a transformer, an output voltage generating unit, a MOS transistor, an output voltage detecting unit, a switching control unit, and a power supply unit. The output voltage detecting unit detects a transformer tertiary winding voltage, compares it with a first reference value, compares the differentiated tertiary winding voltage with a second reference value, and determines the start and end of a detection period based on the two comparisons. The output voltage detecting unit also samples and holds the voltage with two sampling pulses within the detection period, selects one of the two sampled and held voltages, and outputs the selected voltage when the detection period ends.

Abstract: A current flowing through a switching element (5) of a power supply is detected by an AC current transformer (8), and a capacitor (201) is charged by a voltage corresponding to the current. A reduction factor of the terminal voltage of the capacitor in an off period of the switching element (5) is calculated based on an amplification factor of the terminal voltage of the capacitor, an absolute value of an instantaneous value of an input power supply voltage, and an instantaneous value of a direct current output voltage, and the capacitor is discharged so that the terminal voltage of the capacitor decreases by the reduction factor in an off period of the switching element (5). A current flowing through an inductor (4) is estimated from the terminal voltage of the capacitor.

Abstract: A bi-directional DC/DC converter comprises bridge circuits connected to DC voltage sources, an isolation transformer, an LC resonance circuit, and detection circuits for detecting voltages and currents of the DC voltage sources. A control circuit in the power flow from a first DC voltage source to a second DC voltage source changes over between fixed frequency control and frequency modulation control according to the magnitude of a control variable, and a control circuit in the power flow from a second DC voltage source to the first DC voltage source changes over between fixed frequency control and frequency modulation control according to the magnitude of another control variable. Thus, the bi-directional DC/DC converter can be applied to devices with a wide range of input and output voltages.

Abstract: A switching power supply system includes a transformer having a primary winding, a secondary winding and a tertiary winding, a switching device inputted to the primary winding carrying out switching operation on the basis of a first control signal or a second control signal, an output voltage producing section rectifying and smoothing a voltage generated in the secondary winding to produce an output voltage, an output voltage detecting section producing an output voltage detection signal based on a voltage generated in the tertiary winding, a checking pulse generator generating pulses of the first control signal, and a switching controlling section producing the second control signal on the basis of the output voltage detection signal. The switching power supply system is capable of carrying out stable control of the output voltage on the secondary winding side of the transformer with a low power loss.

Abstract: A sound-absorbing body having sound-absorbing characteristics suitable for in-home and car audio systems, wherein the indoor echo of sound wave output from a speaker or echo in a speaker enclosure should be reduced. Namely, showing flat sound-absorbing properties while maintaining a high sound-absorbing ratio in the medium tone range, having a simple structure, is easily installed, water-resistant and is decorative. Specifically, a sound-absorbing body having a plurality of porous members provided with air holes therein and a structure composed by three or more layers formed by bonding the individual porous members via an adhesive layer having a preset thickness, wherein one side of said structure is located in the side of a sound source and the other side of said structure has a peak-and-valley pattern that is formed by alternately positioning said porous members and air layers to thereby flatten and improve the sound-absorbing ratio in the medium tone range.

Abstract: A control system for a power factor correction circuit performs stabilized oscillation operation and suppresses switching frequency variation due to change of the AC power source. A control system includes a voltage error amplifier for outputting a voltage error signal obtained by amplifying a difference between a DC output voltage Vo and a command value Vref of the DC output voltage, a current command value generating circuit for outputting a current command value Vi for controlling the input current Iin, a comparator comparing an inductor current signal obtained by detecting an inductor current running in the switching element by a current detecting resistor with a magnitude of the output signal Vi from the multiplier, a timer circuit for setting an off-period of the switching element corresponding to the voltage Vd, and a reset-set type flip-flop circuit for setting an off-timing of the switching element after an elapse of the off-period.

Abstract: To provide a current estimation circuit that can achieve a reduction in cost, a miniaturization, and a suppression of switching loss, and estimate an inductor current with a high degree of accuracy, despite a variation in the inductance value of the inductor. A current flowing through a switching element (5) is detected by current detection means (8), and a capacitor (201) is charged by a signal voltage corresponding to the current. A reduction factor of a terminal voltage of the capacitor in an off period of the switching element (5) is calculated based on an amplification factor of the terminal voltage of the capacitor, an absolute value of an instantaneous value of an input power supply voltage, and an instantaneous value of a direct current output voltage, and the capacitor is discharged so that the terminal voltage of the capacitor decreases by the reduction factor in an off period of the switching element (5).

Abstract: A power converter includes a small-sized inductor connected to an AC voltage input line for power factor correction and a filter for suppressing conduction noise. The inductor is connected to a rectifier and comprises first and second windings and that are wound on a common magnetic core and loosely coupled with each other. A leakage inductance component of the inductor functions as an energy storage element in a main conversion operation and an excitation inductance component of the inductor functions as a noise reduction element for suppressing an conduction noise caused by on-off operation of a switching element.

Abstract: A switching power supply includes a control circuit controlling ON and OFF of switching devices Q1 and Q2 and having an error amplifying circuit that controls a DC output voltage at a constant preset value, an oscillator circuit that controls the switching frequency in response to the output signal level FB of an error amplifying circuit, and a pulse width control circuit PWM that controls the pulse width in response to the output signal such that the ON-periods of switching devices Q1 and Q2 are equal to each other. The ON and OFF of switching devices Q1 and Q2 is controlled based on the output from oscillator circuit VCO when the output signal is higher than a threshold level. The switching frequency is fixed when the output signal level FB is lower than the threshold level.

Abstract: A sound-absorbing body having sound-absorbing characteristics suitable for in-home and car audio systems, wherein the indoor echo of sound wave output from a speaker or echo in a speaker enclosure should be reduced. Namely, showing flat sound-absorbing properties while maintaining a high sound-absorbing ratio in the medium tone range, having a simple structure, is easily installed, water-resistant and is decorative. Specifically, a sound-absorbing body having a plurality of porous members provided with air holes therein and a structure composed by three or more layers formed by bonding the individual porous members via an adhesive layer having a preset thickness, wherein one side of said structure is located in the side of a sound source and the other side of said structure has a peak-and-valley pattern that is formed by alternately positioning said porous members and air layers to thereby flatten and improve the sound-absorbing ratio in the medium tone range.

Abstract: Sound-absorbing material is provided which is more effective for the same volume. A sound-absorbing body is formed characteristically by hot-compression molding of a raw material (C) comprises a flexible polyurethane foam to a volume ratio ranging from 1/1.5 to 1/12. In the molding, metal molds (A·B) are heated in an electric furnace up to a set temperature of 180° C.; the flexible polyurethane foam of the cell number of 50 is held between the metal molds (A·B), and compressed and heated in the electric furnace in this state at 180° C. for 60 minutes; the fixing clamp is removed; and the hot-compressed urethane foam is taken out to obtain the intended sound-absorbing body.

Abstract: A computerized tomography apparatus and program for obtaining a cross-sectional image corresponding to projections are provided in which, for a temporary cross-sectional image f(x, y) obtained in some manner, an evaluation function E is defined which includes differences between projections calculated from f(x, y) and measured projections, and f(x, y) is changed in a manner which substantially decreases E. The computerized tomography apparatus and program are characterized in which a back projection operation, which is required by conventional computerized tomography, is not essentially required. The computerized tomography apparatus and program are particularly effective in removal or reduction of metal artifacts, aliasing artifacts and the like.

Abstract: A switching power supply exhibits high conversion efficiency and facilitates reducing the size thereof. The switching power supply includes a half-bridge circuit including a first series circuit formed of switching devices Q1 and Q2 and connected between the output terminals of a DC power supply; and a second series circuit connecting primary inductance Lr1 of transformer T1, primary inductance Lr2 of transformer T2 and capacitor Cr in series. The second series circuit is connected between the output terminals of the half-bridge circuit, and is made to conduct a series resonance operation. The switching devices Q1 and Q2 is controlled at the ON-duties of 0.5 for reducing the breakdown voltages of rectifying diodes D1 and D2 on the secondary side of transformers T1 and T2 and for improving the conversion efficiency of the switching device.

Abstract: A switching power supply device includes a first series circuit of first and second switching elements connected in parallel with a DC power supply. An isolation transformer has primary and secondary windings and first and second auxiliary windings, a first layer including the primary windings between a second layer of the two auxiliary windings, and a third layer of the secondary windings. A capacitor in series with the primary windings defines a second series circuit in parallel with the second switching element. A rectifying and smoothing circuit includes a rectifying diode and a smoothing capacitor, connected to the secondary windings. First and second control circuits turn on and off the first and second switching elements based on voltages generated in the two auxiliary windings, to obtain a DC output from the rectifying and smoothing circuit, enabling an adequate auxiliary windings voltage and stable switching operation including stable zero-voltage turn-on.

Abstract: A switch mode power supply according to the invention that can improve the reliability thereof includes a series circuit connected between the positive and negative electrodes of a DC power supply 3, the series circuit including a capacitor 4, a main switching device 1, and a subsidiary switching device 2; a main control circuit 13; a subsidiary control circuit 10; control circuits 13 and 10 turning main switching device 1 and subsidiary switching device 2 alternately ON and OFF to obtain a DC output via a transformer 6; and subsidiary control circuit 10 preventing a voltage exceeding the gate breakdown voltage of subsidiary switching device 2 from being applied to the gate electrode of subsidiary switching device 2.