Abstract: After a contract terminates in a contract part with personal identification and the input of contract contents, a control part controls the door of a sales storing box in which a product to be purchased is stored, and vends the product by opening the door.

Abstract: After a contract terminates in a contract part with personal identification and the input of contract contents, a control part controls the door of a sales storing box in which a product to be purchased is stored, and vends the product by opening the door.

Abstract: Since the IC card does not have a power source in an ordinary case, the power is supplied thereto from the IC card reader/writer via the contact electrode. According to the present invention, a current detect unit is disposed between the power source of the IC card reader/writer and the contact electrode for the power supply to detect the presence/absence of the current supply. A data signal can be delivered from the IC card reader/writer to the IC card only when the current supply is detected by the current detect unit so as to prevent the latch-up phenomenon due to an insufficient contact between the electrodes of the IC card particularly including a complementary MOS and the electrodes of the IC card reader/writer, thereby preventing the destruction of the IC card.

Abstract: A switching power source device, in which a DC voltage obtained by rectifying an AC voltage is converted by switching elements into an AC voltage, which is subjected to voltage conversion by a transformer and rectified by a rectifier circuit to output a DC voltage therefrom. In one embodiment, a resonance capacitor and a saturable transformer form a series resonant circuit, and switching elements are subjected to frequency modulation control. In another embodiment, an inductor connected in parallel with a non-saturable transformer, and a capacitor connected in series to the same transformer, form a series resonant circuit, and the switching elements are subjected to frequency modulation control. In each embodiment, the series resonant circuit is subjected to frequency modulation control, and the electric currents from the switching elements do not rise and fall suddenly. Accordingly, switching losses and noise can be minimized, and the output voltages can be controlled easily.