Abstract: An electronic key device includes a portable device capable of being carried by a user, and a vehicle-mounted device configured to perform mutual communication with the portable device to perform predetermined control. The vehicle-mounted device includes a plurality of antennas that is provided in different positions of a vehicle and is configured to transmit radio waves every predetermined time. A response signal based on the reception strength of the radio waves transmitted from the plurality of antennas is transmitted from the portable device to the vehicle-mounted device. The vehicle-mounted device determines that a moving direction of the portable device heads for any one of the antennas based on the response signal, and when it is determined that a distance between the vehicle and the portable device is equal to or less than a predetermined threshold, control is performed such that a door becomes unlocked.

Abstract: An electronic key device includes a portable device capable of being carried by a user, and a vehicle-mounted device configured to perform mutual communication with the portable device to perform predetermined control. The vehicle-mounted device includes a plurality of antennas that is provided in different positions of a vehicle and is configured to transmit radio waves every predetermined time. A response signal based on the reception strength of the radio waves transmitted from the plurality of antennas is transmitted from the portable device to the vehicle-mounted device. The vehicle-mounted device determines that a moving direction of the portable device heads for any one of the antennas based on the response signal, and when it is determined that a distance between the vehicle and the portable device is equal to or less than a predetermined threshold, control is performed such that a door becomes unlocked.

Abstract: A vehicle-mounted device communication controller includes a vehicle-mounted unit for communicating with ID-registered portable units, a switch-detection mechanism for detecting pressing of an operation knob, a switch-operation restriction mechanism for restricting the rotation of the knob, and a door-opening/closure detection mechanism for detecting opening and closure of a door. Signals are exchanged between the vehicle-mounted unit and each portable unit, and a portable unit having succeeded in exchanging the signals is authenticated and released from the restriction. The vehicle-mounted unit includes a sending/receiving part, a controller, an authentication part, and an ID-storage part.

Abstract: A vehicle-mounted unit includes a controller which changes a setting of a search method of portable units between a simple search method which is based on sending/receiving of simple search signals and simple response signals and an individual search method which is based on sending/receiving of normal search signals and normal response signals, and an ID-storage part which updates and stores the ID of the portable unit authenticated at a latest time as the latest authenticated ID. When the latest authenticated ID is stored in the ID-storage part, the controller searches the portable unit having the latest authenticated ID by priority and by the individual search method.

Abstract: A vehicle-mounted device communication controller includes a vehicle-mounted unit for communicating with ID-registered portable units, a switch-detection mechanism for detecting pressing of an operation knob, a switch-operation restriction mechanism for restricting the rotation of the knob, and a door-opening/closure detection mechanism for detecting opening and closure of a door. Signals are exchanged between the vehicle-mounted unit and each portable unit, and a portable unit having succeeded in exchanging the signals is authenticated and released from the restriction. The vehicle-mounted unit includes a sending/receiving part, a controller, an authentication part, and an ID-storage part.

Abstract: A vehicle-mounted unit includes a controller which changes a setting of a search method of portable units between a simple search method which is based on sending/receiving of simple search signals and simple response signals and an individual search method which is based on sending/receiving of normal search signals and normal response signals, and an ID-storage part which updates and stores the ID of the portable unit authenticated at a latest time as the latest authenticated ID. When the latest authenticated ID is stored in the ID-storage part, the controller searches the portable unit having the latest authenticated ID by priority and by the individual search method.

Abstract: A vanadium electrolytic solution containing highly concentrated and dissolved vanadium is produced by a method wherein a vanadium compound selected from the group consisting of ammonium metavanadate and vanadium pentaoxide is subjected to a reduction operation in the presence of inorganic acids. At this time, by repeating the addition of the concentrated inorganic acids and the vanadium compound, a tetravalent and pentavalent vanadium solution of 3.4 mol/l is obtained.In addition, the resulting vanadium electrolytic solution is electrolyzed, whereby tetravalent vanadium is reduced to be trivalent on the negative electrode and is oxidized into pentavalent vanadium on the positive electrode, and then pentavalent vanadium is reduced into tetravalent vanadium by a reducing agent to form a discharged couple of trivalent and tetravalent vanadium, and an electrolytic solution is obtained which is capable of being charge-discharged.