Minebea Company, Limited

Masashi Norizuki

Takao Takehara

Osamu Kobayashi

Kiyoshi Ito

Hiroshi Shinmen

Atsuyoshi Tamagawa

An inverter transformer in which to overall structure and manufacturing process can be simplified despite its closed magnetic path structure, and a cost increase can be suppressed. Primary windings (,,) and secondary windings (,,) wound around a plurality of rod-like cores (,,) have leakage inductances. The primary windings (,,) axe wound around respective rod-like cores (,,) such that magnetic fluxes being induced in respective cores by the currents flowing through the primary windings (,,) are directed reversely to magnetic fluxes being induced in adjacent cores.

Inverter transformer

An electromagnetic wave absorber is formed of an Mn&#x2014;Zn ferrite including: a spinel primary phase which contains 40.0 to 49.9 mol % FeO, 4.0 to 26.5 mol % ZnO, and the remainder consisting of MnO; and a secondary phase which contains CaO as a base component. In the ferrite, the spinel primary phase accounts for 50.0 to 99.0% of the aggregate mass of the spinel primary phase and the secondary phase.

Electromagnetic wave absorber formed of Mn-Zn ferrite

An electromagnetic wave absorber is formed of an Mn&#x2014;Zn ferrite including: a spinel primary phase which contains 40.0 to 49.9 mol % FeO, 4.0 to 26.5 mol % ZnO, 0.1 to 4.0 mol % TiOand/or SnO, and the remainder consisting of MnO; and a secondary phase which contains CaO as a base component. In the ferrite, the mass of the spinel primary phase accounts for 50.0 to 99.0% of the aggregate mass of the spinel primary phase and the secondary phase.

This invention is to provide an inexpensive high intensity discharge lamp lighting device having a simplified circuit construction, which does not use a full-bridge mode inverter. The high intensity discharge lamp lighting device includes a rectifier for a power-frequency power supply, a booster chopper mode sine wave converter, a zero volt switching push pull inverter, and a high intensity lamp of a halide lamp. And, as a starting device for the halide lamp, the high intensity discharge lamp lighting device generates a high voltage (5 KV) using a resonance by a ballast choke for the inverter and a condenser connected in parallel to the halide lamp, thereby inducing a glow discharge. And, a PFM (pulse frequency modulation) circuit controls the lamp current of the halide lamp to keep it constant. And, when the AC power is turned off and turned on again, a re-lighting circuit after lighting works such that the control IC stops operation by a pulse-by-pulse mode current limiter of an inverter control IC, thereafter a soft starting circuit operates to generate a high voltage on the output of the inverter; when the lamp temperature is so high that the mercury vapor pressure inside the tube goes high and lighting cannot be started, the foregoing operation is repeated to achieve re-lighting.

Power supply circuit device for a high intensity discharge lamp that

A fluorescent lamp circuit having a power-factor improving step-up chopper and an inverter to covert an output of the step-up chopper and to drive the fluorescent lamp. A switching circuit of the step-up chopper and a switching circuit of the inverter are operated by a switching element consisting of a single transistor.

Fluorescent lamp circuit employing both a step-up chopper and an inverter

The present invention is disclosed to provide an inverter allowing a remarkable reduction in the number of parts used for an inverter unit which can improves the efficiency and allows current control in a wide range. Namely, the inverter unit for converting a direct current supplied from DC power supply, into an alternating current by conversion means alternatively converting the flowing direction of direct current by SWITCH ON/SWITCH OFF operation of a switching element, comprises a series resonance circuit formed at the primary side of a step-up transformer, a control means for switching ON/OFF said series resonance circuit by the switching element at a timing led in phase from the resonant frequency of this resonance circuit, and a load connected at the secondary side of the transformer, so as to solve the problems described above.

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Iwata-gun, Japan

Masashi Norizuki