Toshiba Tec Kabushiki Kaisha

Tsuyoshi Takanose

Hiroyuki Kushida

Takuya Ogishima

Masahito Sano

Akiko Numata

Tomokazu Yoshioka

A plurality of optical beacons that emit light in respective light emitting patterns containing an ID code are distributed and installed in a space in which of a mobile body are moved. The mobile body is provided with a detection unit. The detection unit identifies at least three optical beacons according to the ID codes of the lights emitted according to the optical beacons and detects the direction of light emitted according to each of the identified optical beacons. Then, it detects the position of the mobile body according to the outcome of detection.

Position detection system

An electric vacuum cleaner according to the present invention boosts a voltage supplied to a motor-driven blower through the use of a boost converter circuit with a DC power supply as a drive source to thereby increase the output of the motor-driven blower so as to enhance dust suction power. The present invention provides, as operation modes of such an electric vacuum cleaner, an operation mode for boosting power inputted to the motor-driven blower with the boost converter circuit to thereby increase dust suction power, and an operation mode for deactivating the boost converter circuit. Consequently, the boost converter circuit is used to enable the boosting of the power inputted to the motor-driven blower only when really required, and a loss in power produced due to the mounting of the boost converter circuit can be reduced. Thus, the service hour per charge for a battery can be set to a level equivalent to an electric vacuum cleaner equipped with no boost converter circuit.

Electric vacuum cleaner

The present invention aims to first start the rotation of a rotor according to a first sequence for causing currents to flow in armature windings of three phases U, V and W upon startup of a three-phase brushless motor to thereby reduce an inrush current at the startup thereof, thus making it possible to lighten an electrical load on each electronic part used for control. Also the present invention aims to perform switching to an original second sequence for causing currents to flow in the armature windings of the two phases U and V, V and W or W and U of the three-phase brushless motor after the startup of the three-phase brushless motor to thereby provide a period for an open state of each terminal and make dead band control or the like unnecessary, thus making control of the three-phase brushless motor easier.

Drive control circuit for three-phase brushless motor, motor-driven blower and electric vacuum cleaner

An electric vacuum cleaner including a motor-driven blower driven by an inverter circuit. The inverter circuit has a plurality of switching elements. The inverter circuit AC-drives a motor-driven blower according to periodic switching between the switching elements. The periodic switching is based on the detected value of physical quantities related to the electric vacuum cleaner. The electric vacuum cleaner can, in the highest operation mode, undergo a sudden fluid load variation. The electric vacuum cleaner is able to limit, by way of the inverter circuit, the unpleasant sound produced by the vacuum cleaner due to the change in rotation velocity of a rotor of a motor of the vacuum cleaner.

Inverter control circuit of motor-driven blower for electric vacuum cleaner, drive control circuit using the same, and electric vacuum cleaner using drive control circuit

Growing community of inventors

Fuji, Japan

Tsuyoshi Takanose