Hitachi Metals, Ltd.

Hitachi, Ltd.

Metglas, Inc.

Hitachi Ferrite Electronics, Ltd.

Shin Nakajima

Kiyotaka Yamauchi

Yoshihito Yoshizawa

Shunsuke Arakawa

Osamu Shimoe

Yoshio Bizen

Hirohiko Miki

Noriyoshi Hirao

Sadami Kubota

Mutsuhito Sakaguchi

Rihito Kagawa

Kenichi Onda

Hiroyuki Aoyama

Tooru Abe

Kohei Yabuno

Hideaki Shimizu

Akira Yamataka

Michiyuki Fukushima

Noboru Ogawa

Kozin Abe

A transformer includes an iron core formed by using an Fe-based amorphous alloy ribbon and a winding wound around the iron core. The ribbon includes dotted line laser radiation traces arranged on at least a first surface in a casting direction. Each of the dotted line laser radiation traces is formed by arranging laser radiation marks on the first surface along a width direction. A spot space is from 0.10 mm to 0.50 mm. In a case in which a line space is d1 (mm), and the spot space is d2 (mm), a number density D of the laser radiation marks (D=(1/d1)&#xd7;(1/d2)) is from 0.05 marks/mmto 0.50 marks/mm. An iron loss of the ribbon in a single sheet is 0.150 W/kg or less at a frequency of 60 Hz and a magnetic flux density of 1.45 T.

Transformer

A current transformer detects a sine-wave alternating current having a maximum effective current value I(A) and a frequency f(Hz) and a half-sine-wave rectified current having a maximum peak value I(A) and a frequency f(Hz) in a primary winding, consisting of at least one magnetic core with one turn of primary winding and at least one multiple turns of secondary winding to which a detecting resistor is connected.

Current transformer and electric energy meter

A magnetic core for use in a saturable reactor made of an Fe-based soft-magnetic alloy comprising as essential alloying elements Fe, Cu and M, wherein M is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti and Mo, and having an alloy structure at least 50% in area ratio of which being fine crystalline particles having an average particle size of 100 nm or less. The magnetic core has control magnetizing properties of a residual operating magnetic flux density &Dgr;Bb of 0.12 T or less, a total control operating magnetic flux density &Dgr;Br of 2.0 T or more, and a total control gain Gr of 0.10-0.20 T/(A/m) calculated by the equation: Gr&equals;0.8&times;(&Dgr;Br&minus;&Dgr;Bb)/Hr, wherein Hr is a total control magnetizing force defined as a control magnetizing force corresponding to 0.8&times;(&Dgr;Br&minus;&Dgr;Bb)&plus;&Dgr;Bb.

Magnetic core for saturable reactor, magnetic amplifier type multi-output switching regulator and computer having magnetic amplifier type multi-output switching regulator

A small-sized apparatus having an inverter which can satisfy EMC standards by providing a small zero phase-sequence reactor which has a high noise attenuation rate over a wide frequency range and wide working temperature range. The apparatus having an inverter comprising a line-noise filter connected between a power supply and the inverter and a zero phase-sequence reactor connected between the inverter and a load is characterized in that the zero phase-sequence reactor connected between the inverter and the load comprises a tape-wound magnetic core formed by winding a nanocrystalline soft-magnetic alloy tape in which nanocrystalline grains not larger than 50 nm in grain size account for at least 50% in volume of the structure; the tape-wound core having the AC relative initial permeability .mu.ri (10 kHz) at the magnetizing force peak value of 0.05 A/m and the frequency of 10 kHz of 20,000 to 200,000, and the AC relative initial permeability .mu.ri (100 kHz) at the magnetizing force peak value of 0.05 A/m and the frequency of 100 kHz of not less than 10,000.

Apparatus having an inverter

A pulse transformer comprising a magnetic core formed of a thin strip of nanocrystalline soft magnetic alloy in which fine nanocrystalline grains having a grain size of not more than 50 nm occupy at least 50 volume % of the structure, characterized in that the AC relative initial magnetic permeability at -20.degree. C. and 50.degree. C. is not less than 50000.

Magnetic core for pulse transformer and pulse transformer made thereof

An active filter circuit including a smoothing filter including a choke coil comprising a magnetic core composed of a nanocrystalline alloy and having a magnetic gap in at least one portion thereof and at least one conductive wire wound around the magnetic core, the nanocrystalline alloy having a composition of 0.1-3 atomic % of at least one element selected from the group consisting of Cu and Au, 1-7 atomic % of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo and W, 10-17 atomic % of Si, and 4-10 atomic % of B, the balance being substantially Fe and inevitable impurities.

Active filter circuit and power supply apparatus including same

A high-voltage pulse generating circuit of a charge transfer-type comprising a main capacitor for storing input energy and at least one magnetic pulse compression circuit comprising a saturable reactor, a saturable reactor on the side of a load comprising an energy recovery winding connected to the main capacitor via a rectifying element for returning unconsumed pulse energy from the load to the main capacitor. This circuit is suitable for an electrostatic precipitator.

High-voltage pulse generating circuit and electrostatic recipitator

A method for producing a nanocrystalline alloy wherein an amorphous alloy is heat-treated by keeping the temperature at a first heat treatment temperature higher than the crystallization temperature of the amorphous alloy for 0 to less than 5 minutes, and is cooled to room temperature at a cooling rate of 20.degree. C./min or more at least until the temperature falls to 400.degree. C. The amorphous alloy subjected to the first heat treatment may be further heat-treated at a second heat treatment temperature not higher than 500.degree. C. and lower than the first heat treatment temperature while applying a magnetic field. The nanocrystalline alloy produced by the method of the invention has a extremely high specific initial permeability as compared with the conventional nanocrystalline alloy, and is suitable for use in magnetic core of transformers, choke coils, etc.

Method of producing nanocrystalline alloy having high permeability

A nano-crystalline soft magnetic alloy ribbon having a structure being occupied by nano-crystalline particles having an average particle size of 50 nm or less at least 50% of the alloy structure. A ceramic insulation coating is formed on its surface so that the coating becomes thicker at the both ends of the ribbon than at the center in the transverse direction of the ribbon and the thickness dx at the coating ends and the average thickness da of the coating determined by a mass measurement method are in the relations of 1.2 da.ltoreq.dx.ltoreq.5 da and dx.ltoreq.10 .mu.m. With a magnetic core using such a nano-crystalline soft magnetic alloy ribbon, magnetic components including saturable reactor, transformer, saturable transformer, acceleration cavity and surge absorbing elements such as surge block core in neutral beam injector can realize a higher performance. The invention also results in a higher reliability for the devices using such magnetic components.

Nano-crystalline soft magnetic alloy ribbon with insulation coating and

A surge current-suppressing circuit for an accelerator comprising a magnetic device inserted between a high-voltage DC power supply and an ion source for suppressing surge current generated when electric charge stored in a stray capacitance existing between the high-voltage DC power supply and the load is released at the time of short-circuiting of the load. The magnetic device comprises a magnetic core constituted by interlaminar-insulated thin ribbons of an iron-base amorphous or fine crystalline soft magnetic alloy. The iron-base fine crystalline soft magnetic alloy has the composition represented by the general formula:

Surge current-suppressing circuit and magnetic device therein

A first high-voltage pulse generating circuit comprises a magnetic pulse compression circuit having a main saturable reactor provided with a reset circuit, the reset circuit being provided with a second saturable reactor for providing pulse voltage or current for setting a magnetic flux density of the main saturable reactor at a gate initiation point to a predetermined constant level. A second high-voltage pulse generating circuit comprises a magnetic pulse compression circuit having a main saturable reactor, a preset circuit for magnetizing the main saturable reactor to a saturation region thereof, and a set circuit for setting a magnetic flux density of the main saturable reactor at a gate initiation point to a predetermined constant level.

High-voltage pulse generating circuit, and discharge-excited laser and

A high-voltage pulse generating circuit comprising a magnetic pulse compression circuit having a saturable reactor, and a variable inductor provided on the input side of the saturable reactor for controlling a pulse width of voltage pulse to be applied to the saturable reactor. This circuit may be used in discharge-excited lasers such as excimer lasers and accelerators such as linear induction accelerators.

A magnetic device for high-voltage pulse generating apparatuses including (a) at least one cylindrical conductor for defining a cavity, the cylindrical conductor being provided with input and output terminals and an inlet and an outlet for a coolant; (b) at least one sealing member fixed to the cylindrical conductor; (c) a plurality of wound magnetic cores each composed of a magnetic ribbon laminated with an insulating layer, the wound magnetic cores being fixed to the cylindrical conductor with such an interval as to provide a certain space between the adjacent wound magnetic cores; and (d) an outer ring member disposed between each of the magnetic cores and the cylindrical conductor and having at least one path for permitting the coolant to flow therethrough, whereby the coolant flows in a radial or circumferential direction of each wound magnetic core in each space between the adjacent wound magnetic cores.

Magnetic device for high-voltage pulse generating apparatuses

A high-voltage pulse generating apparatus having at least one magnetic switch comprising a magnetic core constituted by an Fe-base soft magnetic alloy ribbon wound in a toroidal form, the alloy having the composition represented by the general formula: ##STR1## wherein M is Co and/or Ni, M' is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti and Mo, M' is at least one element selected from the group consisting of V, Cr, Mn, Al, elements in the platinum group, Sc, Y, rare earth elements, Au, Zn, Sn and Re, X is at least one element selected from the group consisting of C, Ge, P, Ga, Sb, In, Be and As, and a, x, y, z, .alpha., .beta. and .gamma. respectively satisfy 0.ltoreq.a.ltoreq.0.5, 0.1.ltoreq.x.ltoreq.3, 6.ltoreq.y.ltoreq.25, 3.ltoreq.z.ltoreq.15, 14.ltoreq.y+z.ltoreq.30, 1.ltoreq..alpha..ltoreq.10, 0.ltoreq..beta..ltoreq.10 and 0.ltoreq..gamma..ltoreq.10, at least 50% of the alloy structure being fine crystalline particles consisting of a bcc Fe solid solution and having an average particle size of 500 .ANG. or less.

Growing community of inventors

Kumagaya, Japan

Shin Nakajima