Patent US6114940A successfully refreshed from Google Patents.
US6114940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
BALUN transformer core material, BALUN transformer core and BALUN transformer
Assignee: TDK Corp
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Filing: 1998-06-10
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Granted: 2000-09-05
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Expires: 2018-06-10
Abstract
Abstract There is disclosed a BALUN transformer core material which has no magnetic permeability, contains a non-magnetic material and is not influenced by the frequency property of the magnetic permeability even in a high-frequency band. A BALUN transformer core which is obtained by pressing and sintering the BALUN transformer core material has no magnetic permeability and has a high specific resistance. A BALUN transformer which is obtained by applying a winding to the BALUN transformer core is a high-property BALUN transformer which can be operated in a high-frequency band of 600 MHz or more.
Inventors
- 👤 Sei Kakinuma
- 👤 Kouki Sato
- 👤 Masahiro Onizuka
- 👤 Ko Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:59
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/42; H01; H01F; H01F17/00; H01F17/04; H01F17/06; H01F17/062
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
44 words
A BALUN transformer comprising a BALUN transformer core and a bifilar winding around the BALUN transformer core, wherein the BALUN transformer core consists essentially of at least one non-magnetic material selected from the group consisting of an aluminum oxide and a non-magnetic iron oxide.
Claim 2
Dependent Claim
44 words
A BALUN transformer comprising a BALUN transformer core and a bifilar winding around the BALUN transformer core, wherein the BALUN transformer core consists essentially of at least one non-magnetic material selected from the group consisting of an aluminum oxide and a non-magnetic iron oxide.
Claim 3
Dependent Claim
19 words
The BALUN transformer according to claim 1 wherein a content of aluminum oxide is 90% by weight or more.
Claim 4
Dependent Claim
23 words
The BALUN transformer according to claim 2 wherein a density of the sintered material is in a range of 3.5 to 4.3 g/cc.
Claim 5
Dependent Claim
23 words
The BALUN transformer according to claim 2 wherein a density of the sintered material is in a range of 3.8 to 4.0 g/cc.
Claim 6
Dependent Claim
19 words
The BALUN transformer according to claim 1, wherein a content of iron oxide is 90% by weight or more.
Claim 7
Dependent Claim
23 words
The BALUN transformer according to claim 5 wherein a density of the sintered material is in a range of 4.2 to 5.3 g/cc.
Claim 8
Dependent Claim
23 words
The BALUN transformer according to claim 5 wherein a density of the sintered material is in a range of 4.5 to 5.0 g/cc.
Claim 9
Dependent Claim
20 words
The BALUN transformer according to claim 1, wherein said transformer core material consists of said at least one non-magnetic material.
Claim 10
Dependent Claim
40 words
A BALUN transformer comprising: a core consisting essentially of at least one non-magnetic material, and a bifilar winding of conductor wire, wherein said non-magnetic material is selected from the group consisting of an aluminum oxide and a non-magnetic iron oxide.
Claim 11
Dependent Claim
40 words
A BALUN transformer comprising: a core consisting essentially of at least one non-magnetic material, and a bifilar winding of conductor wire, wherein said non-magnetic material is selected from the group consisting of an aluminum oxide and a non-magnetic iron oxide.
Claim 12
Independent Claim
71 words
A method of connecting an unbalanced circuit and a balanced circuit, comprising: providing a BALUN transformer; and connecting said unbalanced circuit and said balanced circuit with said BALUN transformer; wherein said BALUN transformer comprises: a core consisting essentially of at least one non-magnetic material, and a bifilar winding of conductor wire; and wherein said non-magnetic material is selected from the group consisting of an aluminum oxide and a non-magnetic iron oxide.
Claim 13
Independent Claim
71 words
A method of connecting an unbalanced circuit and a balanced circuit, comprising: providing a BALUN transformer; and connecting said unbalanced circuit and said balanced circuit with said BALUN transformer; wherein said BALUN transformer comprises: a core consisting essentially of at least one non-magnetic material, and a bifilar winding of conductor wire; and wherein said non-magnetic material is selected from the group consisting of an aluminum oxide and a non-magnetic iron oxide.
Claim 14
Dependent Claim
17 words
The BALUN transformer of claim 9, wherein said core has a density of 3.5 to 4.3 g/cc.
Claim 15
Dependent Claim
17 words
The BALUN transformer of claim 9, wherein said core has a density of 4.2 to 5.3 g/cc.
Claim 16
Dependent Claim
16 words
The method of claim 10, wherein said core has a density of 3.5 to 4.3 g/cc.
Claim 17
Dependent Claim
16 words
The method of claim 10, wherein said core has a density of 4.2 to 5.3 g/cc.
Claim 18
Dependent Claim
18 words
The BALUN transformer according to claim 9, wherein said core consists of said at least one non-magnetic material.
Claim 19
Dependent Claim
17 words
The method according to claim 10, wherein said core consists of said at least one non-magnetic material.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-09-05 | 2004-03-06 | 2004-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-09-05 | 2008-03-06 | 2008-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-09-05 | 2012-03-06 | 2012-09-05 | $7700.00 | Window Closed / Lapsed |