Patent US5198137A successfully refreshed from Google Patents.
US5198137A
Expired / Lapsed
US
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Thermoplastic coated magnetic powder compositions and methods of making same
Assignee: Hoeganaes Corp
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Filing: 1991-05-17
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Granted: 1993-03-30
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Expires: 2011-05-17
Abstract
Abstract An iron powder composition comprising an iron powder coated with a substantially uniform coating of a thermoplastic material and admixed with a boron nitride powder and a method of utilizing the mixture to produce a magnetic core component is provided. The iron powder mixture is formulated with up to about 1% by weight of boron nitride which reduces the stripping and sliding die ejection pressures during high temperature molding and also improves the permeability of the magnetic part over an extended frequency range.
Inventors
- 👤 Howard G. Rutz
- 👤 Christopher Oliver
- 👤 Brooks Quin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:45
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; B; B22; B22F; B22F1/00; B22F1/10; C; C22; C22C; C22C33/00; C22C33/02; C22C33/0207; C22C33/0228; H01F1/22; H01F1/24; H01F1/26; H01F3/00; H01F3/08; H01F41/00; H01F41/02; H01F41/0206; H01F41/0246; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/24992; Y10T428/25; Y10T428/256; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2998; Y10T428/31504; Y10T428/31507; Y10T428/31533; Y10T428/31721
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
65 words
A ferromagnetic powder composition for molding magnetic components comprising iron core particles having a substantially uniform coating of a thermoplastic material surrounding the iron particles, said thermoplastic material constituting from about 0.001% to about 15% by weight of the iron particles as coated; and boron nitride powder admixed with said coated particles in an amount up to about 1% by weight of the coated particles.
Claim 2
Dependent Claim
65 words
A ferromagnetic powder composition for molding magnetic components comprising iron core particles having a substantially uniform coating of a thermoplastic material surrounding the iron particles, said thermoplastic material constituting from about 0.001% to about 15% by weight of the iron particles as coated; and boron nitride powder admixed with said coated particles in an amount up to about 1% by weight of the coated particles.
Claim 3
Dependent Claim
23 words
The composition of claim 1 wherein the boron nitride is present in an amount of about 0.05-0.4% by weight of the coated particles.
Claim 4
Dependent Claim
38 words
The composition of claim 2 wherein the thermoplastic material constitutes about 0.4-2.0% by weight of the coated particles and the coated particles have an apparent density of from about 2.4 g/cm 3 to about 2.7 g/cm 3 .
Claim 5
Dependent Claim
18 words
The composition of claim 1 wherein the thermoplastic material constitutes about 0.6-0.9% by weight of the coated particles.
Claim 6
Dependent Claim
24 words
The composition of claim 1 wherein the thermoplastic material is selected from the group consisting of polyethersulfone, polyetherimide, polycarbonate, polyphenylene ether, and combinations thereof.
Claim 7
Dependent Claim
20 words
The composition of claim 5 wherein the iron core particles have a weight average particle size of about 10-200 microns.
Claim 8
Dependent Claim
18 words
The composition of claim 1 wherein the thermoplastic material constitutes about 0.4-2.0% by weight of the coated particles.
Claim 9
Dependent Claim
24 words
The composition of claim 7 wherein the thermosplastic material is selected from the group consisting of polyethersulfone, polyetherimide, polycarbonate, polyphenylene ether, and combinations thereof.
Claim 10
Dependent Claim
20 words
The composition of claim 8 wherein the iron core particles have a weight average particle size of about 10-200 microns.
Claim 11
Dependent Claim
18 words
The composition of claim 2 wherein the thermoplastic material constitutes about 0.6-0.9% by weight of the coated particles.
Claim 12
Dependent Claim
24 words
The composition of claim 10 wherein the thermoplastic material is selected from the group consisting of polyethersulfone, polyetherimide, polycarbonate, polyphenylene ether, and combinations thereof.
Claim 13
Dependent Claim
20 words
The composition of claim 11 wherein the iron core particles have a weight average particle size of about 10-200 microns.
Claim 14
Dependent Claim
24 words
The composition of claim 3 wherein the thermoplastic material is selected from the group consisting of polyethersulfone, polyetherimide, polycarbonate, polyphenylene ether, and combinations thereof.
Claim 15
Dependent Claim
20 words
The composition of claim 13 wherein the iron core particles have a weight average particle size of about 10-200 microns.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-03-29 | 1996-09-28 | 1997-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-03-29 | 2000-09-28 | 2001-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-03-29 | 2004-09-28 | 2005-03-30 | $7700.00 | Window Closed / Lapsed |