Abstract: Disclosed is a synchronous rectification type switching power supply apparatus, including: a transformer that receives input voltage on a primary side; a switching element that is to be turned on or off for rectifying current of a secondary coil of the transformer; a control circuit to drive the switching element. The control circuit includes a first timing detection circuit to detect first timing at which forward current flows through a body diode of the switching element, and a second timing detection circuit to detect second timing with counter electromotive voltage that is generated at an instant when the body diode is turned off. The control unit is to generate an on/off control signal for the switching element to turn on the switching element at the first timing, to turn off the switching element before the second timing and to bring off-timing of the switching element close to the second timing.

Abstract: Disclosed is a synchronous rectification type switching power supply apparatus, including: a transformer that receives input voltage on a primary side; a switching element that is to be turned on or off for rectifying current of a secondary coil of the transformer; a control circuit to drive the switching element. The control circuit includes a first timing detection circuit to detect first timing at which forward current flows through a body diode of the switching element, and a second timing detection circuit to detect second timing with counter electromotive voltage that is generated at an instant when the body diode is turned off. The control unit is to generate an on/off control signal for the switching element to turn on the switching element at the first timing, to turn off the switching element before the second timing and to bring off-timing of the switching element close to the second timing.

Abstract: A state detection device is disclosed that is for detecting driving states of plural loads which are connected with each other in parallel and are driven by a driving unit. The state detection device includes a voltage detection unit for detecting voltages applied to the loads; a combined voltage generation unit for generating a combined voltage equivalent to a combination of the detected voltages; and a state detection unit for detecting driving states of the loads based on a magnitude of the combined voltage and magnitudes of the voltages applied to the loads.

Abstract: A state detection device is disclosed that is for detecting driving states of plural loads which are connected with each other in parallel and are driven by a driving unit. The state detection device includes a voltage detection unit for detecting voltages applied to the loads; a combined voltage generation unit for generating a combined voltage equivalent to a combination of the detected voltages; and a state detection unit for detecting driving states of the loads based on a magnitude of the combined voltage and magnitudes of the voltages applied to the loads.

Abstract: Thermostability, age stability, and ignition property at low temperatures of a W/O type emulsion explosive are remarkably improved by incorporating a chelating agent in the W/O type emulsion explosive.

Abstract: A water-in-oil emulsion explosive having a high resistance against dead pressing is obtained by adding a cushioning medium having a high impact energy-absorbing property to a water-in-oil emulsion explosive containing a continuous phase consisting of a carbonaceous fuel, a disperse phase consisting of an aqueous solution of inorganic oxidizer salt and an emulsifier.

Abstract: A gas-retaining agent consisting of bubble assemblies, each bubble assembly being one particle consisting of a large number of bubbles agglomerated into the particle, is effective for improving the safety of water-in-oil emulsion explosive compositions against methane and coal dust, for improving the sympathetic detonability of the explosive compositions and for lowering their detonation velocity without deteriorating their strength.

Abstract: A process for curing unsaturated polyester resins in a very short time at a low temperature using .beta.-amino-.alpha., .beta.-unsaturated ketone and peroxide containing hydroperoxy group without the presence of metallic salt.The product thus obtained is not colored.