US5438339A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Antenna for a radio communication apparatus
Assignee: NEC Corp
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Filing: 1994-02-24
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Granted: 1995-08-01
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Expires: 2014-02-24
Abstract
Abstract A miniature and high performance antenna applicable to a radio communication apparatus and made up of a straight antenna rod and an antenna coil or coil element. A first whip antenna has a first portion retractable into the casing of the apparatus and a second portion constantly positioned externally of the casing. A second whip antenna has a coil element in the form of a loading coil having a predetermined number of turns. The second whip antenna is coaxially provided on the upper end of the first whip antenna and slidable relative to and in the axial direction of the first whip antenna. The second portion of the first whip antenna is movable between a position where one end of the coil element is disengaged from one end of the second portion and a position where the former is engaged with the latter. The antenna exhibits a desirable electric characteristic when pulled out of the casing of the apparatus and, in addition, promotes the efficient use of the limited space available in the casing.
Inventors
- 👤 Ryoh Itoh
- 👤 Yukio Yokoyama
- 👤 Takao Ono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:35
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/08; H01Q1/10; H01Q1/12; H01Q1/22; H01Q1/24; H01Q1/241; H01Q1/242; H01Q1/243
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
137 words
An antenna for a radio communication apparatus, comprising: a first whip antenna having a first portion retractable into a casing of said apparatus and a second portion constantly positioned externally of said casing; and a second whip antenna having a coil element in the form of a loading coil having a predetermined number of turns, said second whip antenna being coaxially provided on an upper end of said first whip antenna and slidable relative to and in an axial direction of said first whip antenna such that said second portion of said first whip antenna is movable between a position where one end of said coil element is disengaged from one end of said second portion and a position where said one end of said coil element is engaged with said one end of said second portion.
Claim 2
Dependent Claim
137 words
An antenna for a radio communication apparatus, comprising: a first whip antenna having a first portion retractable into a casing of said apparatus and a second portion constantly positioned externally of said casing; and a second whip antenna having a coil element in the form of a loading coil having a predetermined number of turns, said second whip antenna being coaxially provided on an upper end of said first whip antenna and slidable relative to and in an axial direction of said first whip antenna such that said second portion of said first whip antenna is movable between a position where one end of said coil element is disengaged from one end of said second portion and a position where said one end of said coil element is engaged with said one end of said second portion.
Claim 3
Dependent Claim
35 words
An antenna as claimed in claim 1, wherein said coil element of said second whip antenna is disposed in a case made of synthetic resin, said case having a bore coaxial with said loading coil.
Claim 4
Dependent Claim
34 words
An antenna as claimed in claim 2, wherein said second portion of said first whip antenna has a greater diameter than said first portion and is slidably received in said bore of said case.
Claim 5
Dependent Claim
44 words
An antenna as claimed in claim 2, wherein said case comprises annular positioning ribs projecting radially inwardly of said bore, said annular positioning ribs releasably retaining said one end of said coil element in one or the other of said engaged and disengaged positions.
Claim 6
Dependent Claim
101 words
An antenna as claimed in claim 2, further comprising a connector portion mounted on said casing and surrounding said first whip antenna, said connector portion connecting (a) said first whip antenna to a feed means when said first portion of said first whip antenna is extended from said casing and said one end of said second portion is disengaged from said coil element, and (b) said second whip antenna to said feed means when said first portion of said first whip antenna is retracted into said casing and said one end of said second portion is engaged with said coil element.
Claim 7
Dependent Claim
56 words
An antenna as claimed in claim 5, wherein said first and second portions of said first whip antenna and said bore of said case are so dimensioned that when said first portion is retracted into said casing and said one end of said second portion is in said engaged position, said case contacts said connector portion.
Claim 8
Dependent Claim
39 words
An antenna as claimed in claim 6, further comprising a ground member mounted inside said casing and making electrical contact with said first whip antenna when said first portion of said first whip antenna is retracted into said casing.
Claim 9
Dependent Claim
18 words
An antenna as claimed in claim 1, wherein said first whip antenna has a telescopic rod antenna structure.
Claim 10
Dependent Claim
101 words
An antenna as claimed in claim 1, further comprising a connector portion mounted on said casing and surrounding said first whip antenna, said connector portion connecting (a) said first whip antenna to a feed means when said first portion of said first whip antenna is extended from said casing and said one end of said second portion is disengaged from said coil element, and (b) said second whip antenna to said feed means when said first portion of said first whip antenna is retracted into said casing and said one end of said second portion is engaged with said coil element.
Claim 11
Dependent Claim
39 words
An antenna as claimed in claim 1, further comprising a ground member mounted inside said casing and making electrical contact with said first whip antenna when said first portion of said first whip antenna is retracted into said casing.
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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) | 1998-07-31 | 1999-01-30 | 1999-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-31 | 2003-01-30 | 2003-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-31 | 2007-01-30 | 2007-08-01 | $7700.00 | Window Closed / Lapsed |