Patents by Inventor Kiyotaka Yamauchi
Kiyotaka Yamauchi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 5591276Abstract: There is provided according to the present invention a magnetic alloy with ultrafine crystal grains having a composition represented by the general formula:Fe.sub.100-x-y M.sub.x B.sub.y (atomic %)wherein M represents at least one element selected from Ti, Zr, Hf, V, Nb, Mo, Ta, Cr, W and Mn, 4.ltoreq.x.ltoreq.15, 2.ltoreq.y.ltoreq.25, and 7.ltoreq.x+y.ltoreq.35, at least 50% of the alloy structure being occupied by crystal grains having an average grain size of 500 .ANG. or less, and the crystal grains being based on a bcc structure. It may further contain X (Si, Ge, P, Ga, etc.) and/or T (Au, Co, Ni, etc.). This magnetic alloy has an excellent saturation magnetic flux density, permeability and heat resistance.Type: GrantFiled: November 19, 1993Date of Patent: January 7, 1997Assignee: Hitachi Metals, Ltd.Inventors: Yoshihito Yoshizawa, Yoshio Bizen, Shigekazu Suwabe, Kiyotaka Yamauchi, Toshikazu Nishiyama
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Patent number: 5443664Abstract: 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:(Fe.sub.1-a M.sub.a).sub.100-x-y-z-.alpha. Cu.sub.x Si.sub.y.sub.B.sub.z M'.sub..alpha.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, and a, x, y, z and .alpha. respectively satisfy 0.ltoreq.a.ltoreq.0.5, 0.1.ltoreq..times..ltoreq.3, 0.ltoreq.y.ltoreq.30, 0.ltoreq.z.ltoreq.25, 5.ltoreq.y+z.ltoreq.30 and 0.1.ltoreq..Type: GrantFiled: November 8, 1989Date of Patent: August 22, 1995Assignee: Hitachi Metals, Ltd.Inventors: Shin Nakajima, Noriyoshi Hirao, Kiyotaka Yamauchi, Osamu Shimoe
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Patent number: 5337033Abstract: A permanent magnet assembly for stably fixing a denture comprising a permanent magnet, a casing made of a corrosion-resistant, magnetic material having a cavity for receiving the permanent magnet, and a seal plate for covering an opening of the casing to prevent the permanent magnet from exposing outside, the seal plate consisting of a seal ring member made of a corrosion-resistant, non-magnetic material and a disc plate made of a corrosion-resistant, soft-magnetic material and having substantially the same outer diameter as the inner diameter of the seal ring member, the seal ring member and the disc plate being concentrically arranged in the same plane, the disc plate being welded to the seal ring member in their abutment, and the seal ring member being welded to the casing. Laser welding is utilized.Type: GrantFiled: January 15, 1992Date of Patent: August 9, 1994Assignee: Hitachi Metals, Ltd.Inventors: Yohsuke Kinouchi, Minoru Ai, Hiroshi Mizutani, Osamu Okuno, Kiyotaka Yamauchi, Akira Yamataka, Hiroya Suzuki
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Patent number: 5160379Abstract: An Fe-base soft magnetic alloy having the composition represented by the general formula:(Fe.sub.1-a M.sub.a).sub.100-x-y-z-.alpha.-.beta.-.gamma. Cu.sub.x Si.sub.y B.sub.z M'.sub..alpha. M".sub..beta. X.sub..gamma.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, 0.ltoreq.y.ltoreq.30, 0.ltoreq.z.ltoreq.25, 5.ltoreq.y+z.ltoreq.30, 0.1.ltoreq..alpha..ltoreq.30, .beta..ltoreq.10 and .gamma..ltoreq.10, at least 50% of the alloy structure being fine crystalline particles having an average particle size 1000 .ANG. or less.Type: GrantFiled: January 22, 1991Date of Patent: November 3, 1992Assignee: Hitachi Metals, Ltd.Inventors: Yoshihito Yoshizawa, Kiyotaka Yamauchi, Shigeru Oguma
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Patent number: 5151137Abstract: A magnetic alloy with ultrafine crystal grains having a composition represented by the general formula:Co.sub.100.sub.-x-y-z-a-b Fe.sub.a M.sub.x B.sub.y X.sub.z T.sub.b (atomic %)wherein M represents at least one element selected from Ti, Zr, Hf, V, Nb, Mo, Ta, Cr, W and Mn, X represents at least one element selected from Si, Ge, P, Ga, Al and N, T represents at least one element selected from Cu, Ag, Au, platinum group elements, Ni, Sn, Be, Mg, Ca, Sr and Ba, 0<a.ltoreq.30, 2.ltoreq.x.ltoreq.15, 10.ltoreq.y.ltoreq.25, 0.ltoreq.z.ltoreq.10, 0<b.ltoreq.10, and 12<x+y+z+b.ltoreq.35. Such a magnetic alloy can be produced by producing an amorphous alloy having the above composition, and subjecting the resulting amorphous alloy to a heat treatment to cause crystallization, thereby providing the resulting alloy having a structure, at least 50% of which is occupied by crystal grains having an average grain size of 500 .ANG. or less.Type: GrantFiled: November 16, 1990Date of Patent: September 29, 1992Assignee: Hitachi Metals Ltd.Inventors: Yoshihito Yoshizawa, Yoshio Bizen, Kiyotaka Yamauchi, Toshikazu Nishiyama, Shigekazu Suwabe
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Patent number: 5114503Abstract: A magnetic core comprised of an amorphous alloy ribbon wound into a toroidal shape, wherein the said amorphous alloy has a composition of the formula:(Co.sub.1-x-y-z Fe.sub.x Ni.sub.y Mn.sub.z).sub.100-a-b-c M.sub.a Si.sub.b B.sub.cwherein M is at least one element selected from the group consisting of Nb, Cr and Mo, and x, y, z, a, b and c are numbers which satisfy relations of 0<a.ltoreq.6, 13.ltoreq.b.ltoreq.16, 7.ltoreq.b.ltoreq.10, 0<x.ltoreq.0.1, 0.ltoreq.y.ltoreq.0.2 and 0.ltoreq.x.ltoreq.0.13 respectively, said amorphous alloy after heat treatment having a rectangular ratio Br/Bs of at least 80%, a Bs value in a range of 5 KG to 8 KG and a stress relief ratio of at least 75%.Type: GrantFiled: March 24, 1987Date of Patent: May 19, 1992Assignee: Hitachi Metals, Inc.Inventors: Yoshihito Yoshizawa, Kiyotaka Yamauchi
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Patent number: 5083366Abstract: A wound magnetic core constituted by (a) a thin ribbon made of a fine crystalline, soft magnetic Fe-base alloy having the composition represented by the general formula:(Fe.sub.1-a M.sub.a).sub.100-x-y-z-.alpha. Cu.sub.x Si.sub.y B.sub.z M'.sub..alpha.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, and a, x, y, z and .alpha. respectively satisfy 0.ltoreq.a.ltoreq.0.5, 0.1.ltoreq.x.ltoreq.3, 0.ltoreq.y.ltoreq.30, 0.ltoreq.z.ltoreq.25, 5.ltoreq.y+z.ltoreq.30 and 0.1.ltoreq..alpha..ltoreq.30, at least 50% of the alloy structure being occupied by fine crystal grains having an average grain size of 1000 .ANG. or less; and (b) a heat-resistant insulating layer having a thickness of 0.5-5 .mu.m formed on at least one surface of the thin ribbon, the heat-resistant insulating layer being made of a uniform mixture of 20-90 weight %, as SiO.sub.Type: GrantFiled: August 1, 1991Date of Patent: January 28, 1992Assignee: Hitachi Metals, Ltd.Inventors: Shunsuke Arakawa, Kiyotaka Yamauchi, Noriyoshi Hirao
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Patent number: 5072205Abstract: A wound magnetic core constituted by (a) a thin ribbon made of a fine crystalline, soft magnetic Fe-base alloy having the composition represented by the general formula:(Fe.sub.1-a M.sub.a).sub.100-x-y-z-.alpha. Cu.sub.x Si.sub.y B.sub.z M'.sub..alpha.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, and a, x, y, z and .alpha. respectively satisfy 0.ltoreq.a.ltoreq.0.5, 0.1.ltoreq.x.ltoreq.3, 0.ltoreq.y.ltoreq.30, 0.ltoreq.z.ltoreq.25, 5.ltoreq.y+z.ltoreq.30 and 0.1.ltoreq..alpha..ltoreq.30, at least 50% of the alloy structure being occupied by fine crystal grains having an average grain size of 1000 .ANG. or less; and (b) a heat-resistant insulating layer having a thickness of 0.5-5 .mu.m formed on at least one surface of the thin ribbon, the heat-resistant insulating layer being made of a uniform mixture of 20-90 weight %, as SiO.sub.Type: GrantFiled: February 1, 1990Date of Patent: December 10, 1991Assignee: Hitachi Metals, Ltd.Inventors: Shunsuke Arakawa, Kiyotaka Yamauchi, Noriyoshi Hirao
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Patent number: 5069731Abstract: A low-frequency transformer including a magnetic core made of an alloy having the composition represented by the general formula:(Fe.sub.1-a M.sub.a).sub.100-x-y-z-.alpha. Cu.sub.x Si.sub.y B.sub.z M'.sub..alpha. (atomic %)wherein M is Co and/or Ni, M' is at least one element selected from the group consisting of Nb, W, Ta, Mo, Zr, Hf and Ti, and a, x, y, z and .alpha. respectively satisfy 0.ltoreq.a.ltoreq.0.3, 0.1.ltoreq.x.ltoreq.3, 0.ltoreq.y.ltoreq.17, 4.ltoreq.z.ltoreq.17, 10.ltoreq.y+z.ltoreq.28 and 0.1.ltoreq..alpha..ltoreq.5, at least 50% of the alloy structure being occupied by fine crystal grains having an average grain size of 1000 .ANG. or less when measured by their maximum diameters. The alloy may further contain at least one element selected from the group consisting of Ge, P, C, Ga, Al and N.Type: GrantFiled: March 23, 1989Date of Patent: December 3, 1991Assignee: Hitachi Metals, Ltd.Inventors: Yoshihito Yoshizawa, Kiyotaka Yamauchi
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Patent number: 4985089Abstract: Fe-base soft magnetic alloy powder and dust core having the composition represented by the general formula:(Fe.sub.1-a M.sub.a).sub.100-x-y-z-.alpha.-.beta.-.gamma. Cu.sub.x Si.sub.y B.sub.z M'.sub..alpha. M".sub..beta. X.sub..gamma.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, 0.ltoreq.y.ltoreq.30, 0.ltoreq.z.ltoreq.25, 0.ltoreq.y+z.ltoreq.35, 0.1.ltoreq..alpha..ltoreq.30, 0.ltoreq..beta..ltoreq.10 and 0.ltoreq..gamma..ltoreq.10, at least 50% of the alloy structure being fine crystalline particles having an average particle size of 500 .ANG. or less.Type: GrantFiled: July 25, 1988Date of Patent: January 15, 1991Assignee: Hitachi Metals, Ltd.Inventors: Yoshihito Yoshizawa, Kiyotaka Yamauchi
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Patent number: 4983859Abstract: 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.Type: GrantFiled: August 22, 1989Date of Patent: January 8, 1991Assignee: Hitachi Metals, Ltd.Inventors: Shin Nakajima, Akira Yamataka, Hideaki Shimizu, Kiyotaka Yamauchi, Shunsuke Arakawa
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Patent number: 4945339Abstract: An anti-theft sensor marker is disclosed which has good sensitivity characteristics and which does not readily deteriorate due to bending stress. The marker is mainly composed of an alloy ribbon and is employed in an anti-theft system in which the stealing of a commodity previously marked by the marker is determined by detecting a magnetic field of a specific frequency with respect to an incident magnetic field intensity applied to a detection region through the alloy ribbon of the marker when the marker is disposed within the detection region.Type: GrantFiled: November 16, 1988Date of Patent: July 31, 1990Assignee: Hitachi Metals, Ltd.Inventors: Kiyotaka Yamauchi, Yoshihito Yoshizawa
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Patent number: 4918555Abstract: A magnetic head having at least one magnetic gap in its magnetic path, which comprises an Fe-base solf magnetic alloy layer in the magnetic path, at least 50% of the structure of said alloy layer consisting of fine crystalline particles having a body-centered cubic structure and an average particle size of 500 .ANG. or less.Type: GrantFiled: July 25, 1988Date of Patent: April 17, 1990Assignee: Hitachi Metals, Ltd.Inventors: Yoshihito Yoshizawa, Kiyotaka Yamauchi, Toshikazu Nishiyama, Shigekazu Suwabe
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Patent number: 4881989Abstract: An Fe-base soft magnetic alloy having the composition represented by the general formula:(Fe.sub.1-a M.sub.a).sub.100-x-y-z-.alpha.-.beta.-.gamma. Cu.sub.x Si.sub.y B.sub.z M'.sub.60 M".sub..beta. X.sub..gamma.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, 0.ltoreq.y.ltoreq.30, 0.ltoreq.z.ltoreq.25, 5.ltoreq.y+z.ltoreq.30, 0.1.ltoreq..alpha..ltoreq.30, .beta..ltoreq.10 and .gamma..ltoreq.10, at least 50% of the alloy structure being fine crystalline particles having an average particle size of 1000 .ANG. or less.Type: GrantFiled: October 1, 1987Date of Patent: November 21, 1989Assignee: Hitachi Metals, Ltd.Inventors: Yoshihito Yoshizawa, Kiyotaka Yamauchi, Shigeru Oguma
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Patent number: 4871925Abstract: 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.Type: GrantFiled: October 24, 1988Date of Patent: October 3, 1989Assignee: Hitachi Metals, Ltd.Inventors: Kiyotaka Yamauchi, Yoshihito Yoshizawa, Shin Nakajima
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Patent number: 4827214Abstract: A novel method and system for measuring AC magnetic characteristics is disclosed, in which the loss of a magnetic core is measured by defining the change rate of magnetic flux density, and for this purpose, the duration of a voltage induced in the coil of an object magnetic core during the gate period is detected and controlled by an input voltage, a reset current and a load resistor.Type: GrantFiled: September 22, 1987Date of Patent: May 2, 1989Assignee: Hitachi Metals, Ltd.Inventors: Shin Nakajima, Kiyotaka Yamauchi
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Patent number: 4811187Abstract: A DC-DC converter having a transformer having a primary winding and a secondary winding; means for supplying DC input voltage to the primary winding; at least one switching element connected between the DC input voltage supplying means and the primary winding; rectifying means; at least one saturable reactor having a first winding and a second winding, the first winding being connected between one end of the secondary winding which is positive while the switching element is in a turn-on state and the rectifying means; and reset control circuit means connected to the second winding of the saturable reactor for supplying reset voltage thereto in response to output voltage of the rectifying means. The first and second windings have such polarities that the reset voltage can reset the saturable reactor during a turn-off period of the switching element. This DC-DC converter enjoys less temperature rise in the saturable reactor and a lower level of noise generation.Type: GrantFiled: October 20, 1987Date of Patent: March 7, 1989Assignee: Hitachi Metals Ltd.Inventors: Shin Nakajima, Kiyotaka Yamauchi, Osamu Shimoe
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Patent number: 4769091Abstract: A magnetic core comprised of an amorphous metal alloy having a composition represented by the formula:(Co.sub.1-a-b-c Fe.sub.a Mn.sub.b Mo.sub.c).sub.100-x-y Si.sub.x B.sub.y (in atomic %)wherein a, b, c, x and y are numbers which respectively satisfy relations 0.ltoreq.a.ltoreq.0.05, 0.03.ltoreq.b.ltoreq.0.08, 0.01.ltoreq.c.ltoreq.0.04, 0.04.ltoreq.b+c.ltoreq.0.10, 14.ltoreq.x.ltoreq.16 and 7.5.ltoreq.y.ltoreq.9.5, and the core is treated by a process including a step to keep the core at least one time at a temperature between 0.95.times.Tc and 150.degree. C. for a time of one hour to ten hours in a magnetic field, the direction of which is generally coincidental with the direction of the magnetic path in the core.Type: GrantFiled: August 10, 1987Date of Patent: September 6, 1988Assignee: Hitachi Metals Ltd.Inventors: Yoshihito Yoshizawa, Shin Nakajima, Kiyotaka Yamauchi
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Patent number: 4757219Abstract: A lamination type of magnetostrictor incorporated with a mass of plural plates of amorphous metal alloy material laminated by means of a binder wherein the thickness of the plates is equal to or more than 80 .mu.m and the space factor of amorphous metal alloy in the mass is equal to or more than 80% and a manufacturing method thereof.Type: GrantFiled: January 30, 1986Date of Patent: July 12, 1988Assignees: Hitachi Metals, Ltd., Hitachi Ltd.Inventors: Kiyotaka Yamauchi, Yoshihito Yoshizawa, Kiyoshi Koyano