Hitachi, Ltd.

Hitachi Automotive Eng. Co., Ltd.

Kunio Ishiyama

Tomoki Nakamura

Hisashi Nose

Kentaro Oku

Hidehiro Koumura

Teruaki Odaka

Shoichi Noguchi

Syouichi Noguchi

A color cathode ray tube comprises a vacuum vessel including a panel portion having a phosphor screen on its inner face, a neck portion and a funnel portion joining the neck portion and the panel portion. An inline electron gun is disposed inside of the neck portion and includes a main lens and cathode producing a center electron beam and two side electron beams. A deflection yoke for deflecting the electron beams and a pair of 2-pole ring magnets for adjusting electron beam trajectory are disposed around the neck portion. The 2-pole ring magnets have a magnetic flux density distribution at a circle which is concentric with the ring magnets, wherein the radius of the circle corresponds to the distance between adjacent electron beams at the main lens. The ratio of the amplitude of the flux density in the radial component compared to the amplitude of the flux density in the circumferential component is 0.86 to 1.38 on the circle.

Color cathode ray tube having adjustment magnet assembly at neck portion

A color cathode ray tube has a vacuum vessel including a panel portion having a phosphor screen on its inner face, a neck portion and a funnel portion jointing the neck portion and the panel portion; an electron gun assembly including an electrostatic main lens disposed in the neck portion; a deflection yoke arranged around the neck side of the funnel portion for deflecting three in-line arranged electron beams emitted from the electron gun assembly to the phosphor screen; and a 2-pole ring magnet arranged around the neck portion for adjusting the trajectories of the electron beams. The 2-pole ring magnet is arranged to have its center closer to the phosphor screen than is the center of the electrostatic main lens of the electron gun assembly. The value, as calculated by dividing the value of the radial component amplitude of the magnetic field distribution of the 2-pole ring magnet on the circumference of a circle having a radius of the s-size, by the value of the circumferential component amplitude, is 0.86 to 1.38, and preferably 0.955 to 1.275.

Color cathode ray tube having adjustment magnet assembly at the neck portion of the tube

A high frequency heating method includes the steps of controlling a closing period of a switching circuit on the basis of a specified magnetron output value and setting the closing period thereof to a predetermined value. A high frequency heating system includes a heating output control circuit for controlling the closing period thereof on the basis of the specified magnetron output value and an initial output limit circuit for controlling the closing period thereof to a predetermined value.

High frequency heating system and method thereof

In a magnetron power supply for obtaining a high voltage for an anode by an inverter circuit, there is disclosed the improvement including a detector for detecting an AC output current of a secondary-side high voltage winding of a transformer instead of detecting an anode current (after being rectified) for the magnetron to control a magnetron output to a desired value. In this constitution, a current value is detected by clipping a positive or negative side of an output of the detector.

Power supply for a magnetron

Disclosed is a switching power source having a series connection composed of a main transformer, a current-suppressing inductance element, and a switching element and connected across a DC input power source, in which output windings are additionally wound on the main transformer and the inductance elements respectively and those output windings are connected in series to each other so as to form an auxiliary power source for a control circuit for driving/controlling the ON-OFF of the switching element, and a starting circuit is provided to supply power from the DC input power source to the control circuit only during the starting time of the switching power source.

Supply having a load invariant auxiliary power supply supplied from a

A power supply for a magnetron comprises an inverter circuit for converting a direct voltage obtained from a commercial frequency power source into an alternating voltage of a higher frequency by switching a switching element, a transformer with its primary winding connected to the inverter circuit, a voltage doubler with its input connected to a secondary winding of the transformer and with its output connected between a filament and an anode of a magnetron, and a resonant circuit formed in the voltage doubler for smoothing a current through the magnetron.

Growing community of inventors

Mobara, Japan

Kunio Ishiyama