US3586757A - Flexible stripline transmission line - Google Patents
Flexible stripline transmission line Download PDFInfo
- Publication number
- US3586757A US3586757A US850151A US3586757DA US3586757A US 3586757 A US3586757 A US 3586757A US 850151 A US850151 A US 850151A US 3586757D A US3586757D A US 3586757DA US 3586757 A US3586757 A US 3586757A
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- US
- United States
- Prior art keywords
- stripline
- pair
- conductors
- insulator means
- insulating strips
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B7/00—Insulated conductors or cables characterised by their form
- H01B7/0009—Details relating to the conductive cores
- H01B7/0018—Strip or foil conductors
Definitions
- a stripline transmission line is constructed so that the individual conducting and insulating portions of the stripline are free to move relative to each other. This form of construction permits the stripline to be bent to a very small radius without distortion or degradation of its electrical characteristics.
- stripline As presently manufactured, is flexible only to a limited degree. Since the parallel wires of stripline must be held in a fixed relationship to obtain the desired impedance, it is important that bends in the stripline do not cause distortion'of the dielectric and relative displacement of the parallel conductors. If a bend is too sharp, the parallel conductors can be displaced and this displacement may result in transmission line discontinuities which cause reflections and standing waves, thereby degrading the electrical performance of the transmission line.
- stripline has a minimum bending radius which precludes its use in very small spaces or in the manufacture of small components such as the windings of a small pulse transformer.
- Another object of this invention is to provide a stripline transmission line which is flexible.
- Another object of this invention is to provide a stripline capable of being bent to a small radius without degradation of its electrical properties.
- the insulating strips may be made from a polytetrafluoroethylene such as TEFLON.
- FIG. 1 is a cross-sectional view of the stripline transmission line of this invention
- FIG. 2 is an isometric cross-sectional view of the stripline of FIG. 1;
- FIG. 3 is a cross-sectional view of another embodiment of the stripline transmission line.
- FIGS. 1 and 2 there is shown a cross section and isometric cross section view of the stripline transmission line of this invention. Identical portions of FIGS. 1 and 2 have the same reference numbers.
- the stripline consists of a pair of flat metallic conductors l and II separated by an insulator 13.
- the insulator I3 is not mechanically secured to either of the metallic conductors and therefore the conductors are free to slide over the insulator.
- Insulator 15 is positioned adjacent conductor 10 so that conductor 10 is between insulators 13 and 15.
- Insulator I6 is positioned ad acent conductor 11 so that conductor 11 is between insulators l3 and 16.
- Neither insulators 15 nor 16 are secured to the conductor adjacent thereto so that conductors l0 and 11 are free to move relative to the insulators on each side and to each other.
- insulators l3, l5 and 16 may be made from a material having a low coefficient of friction such as the polytetrafluoroethylene TEFLON.
- the conductors l0 and 11 and the insulating strips l3, l5 and 16 are made in the form of flat, thin flexible strips arranged in the rectangular configuration shown. Covers 18 and 19 of flexible insulating material surround the conductors and insulating strips to hold them in the proper relationship. Covers l8 and 19 are joined at 21 and 22 to form a sealed enclosure for the stripline.
- FIG. 3 there is shown a cross-sectional view of another embodiment of this invention.
- Conductors 26 and 27 are separated by insulator 29 in the same manner as conductors l0 and II are separated by insulator 13.
- the insulating strips 15 and 16 of FIGS. 1 and 2 are not used and covers 31 and 32 are positioned directly adjacent conductors 26 and 27. Covers 31 and 32 are free to move relative to the conductors 26 and 27 and are joined at 33 and 34 to form a sealed enclosure for the stripline.
- Covers 31 and 32 may be formed of a polytetrafluoroethylene material.
- stripline having the features illustrated in FIGS. 1 to 3 has been constructed with a thickness of approximately 0.025 inch and a width of from 0.025 to 0.125 inch.
- the elements of the stripline are free to move relative to each other when the line is bent to a small radius the elements of the stripline do not distort to form discontinuities in the transmission line. Thus the electrical characteristics of the line are not degraded when the line is used in equipment where it must be bent to a small radius.
- a stripline including in combination, a pair of bare electrical conductors positioned in parallel relationship, first insulator means slidably positioned between and in direct contact with said conductors, said conductors and said first insulator means being formed of flexible material of substantially equal width forming a rectangular configuration, and second insulator means disposed about said pair of conductors and said first insulator means in a restraining slidable engagement with said pair of conductors.
- said second insulator means includes a pair of insulating strips each positioned adjacent and in direct contact with a separate one of said electrical conductors to position each of said electrical conductors between said first insulator means and one of said pair of insulating strips, said pair of insulating strips being in slidable engagement with said electrical conductors, said second insulator means further including cover means surrounding said electrical conductors, said first insulator means and said pair of insulating strips and holding the same in desired relationship.
Abstract
A stripline transmission line is constructed so that the individual conducting and insulating portions of the stripline are free to move relative to each other. This form of construction permits the stripline to be bent to a very small radius without distortion or degradation of its electrical characteristics.
Description
United States Patent Inventor Merle Haldeman, Jr.
Downers Grove, Ill.
Appl. No. 850,151
Filed Aug. 14, 1969 Patented J 55 22 1971 Assignee The United States 01' America as represented by the United States Atomic Energy Commission FLEXIBLE'STRIPLINE TRANSMISSION LINE 4 Claims, 3 Drawing Figs.
U.S.Cl 174/117 FF, 333/84 M Int. Cl '1 1101b 7/0 8 FieldoISearch 333/84, 84
Primary Examiner-E. A. Goldberg Attorney-Roland A. Anderson ABSTRACT: A stripline transmission line is constructed so that the individual conducting and insulating portions of the stripline are free to move relative to each other. This form of construction permits the stripline to be bent to a very small radius without distortion or degradation of its electrical characteristics.
-'\IIIIIIIIIIIUA\\\ 'III/II/flI/I/ FLEXIBLE STRIPLINE TRANSMISSION LINE CONTRACTUAL ORIGIN OF THE INVENTION The invention described herein was made in the course of, or under, a contract with The United States Atomic Energy Commission.
BACKGROUND OF THE INVENTION In order to construct the miniature electronic equipment in use today it is desirable to have conductors and transmission lines which can be bent to very small radii without degradation of their electricalcharacteristics. In particular stripline, as presently manufactured, is flexible only to a limited degree. Since the parallel wires of stripline must be held in a fixed relationship to obtain the desired impedance, it is important that bends in the stripline do not cause distortion'of the dielectric and relative displacement of the parallel conductors. If a bend is too sharp, the parallel conductors can be displaced and this displacement may result in transmission line discontinuities which cause reflections and standing waves, thereby degrading the electrical performance of the transmission line. Thus stripline has a minimum bending radius which precludes its use in very small spaces or in the manufacture of small components such as the windings of a small pulse transformer.
It is therefore an object of this invention to provide an improved form of stripline transmission line.
Another object of this invention is to provide a stripline transmission line which is flexible.
Another object of this invention is to provide a stripline capable of being bent to a small radius without degradation of its electrical properties.
SUMMARY OF THE INVENTION ductive strips so that the insulators and conductive strips are free to move with respect to each other. Thus, when the stripline is bent to a small radius, the conductive strips and insulators move with respect to each other to permit flexure of the stripline transmission line without distortion of the line damaging to its electrical characteristics. In order to decrease the friction between the conductive and insulating strips, the insulating strips may be made from a polytetrafluoroethylene such as TEFLON.
BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated in the drawings of which:
FIG. 1 is a cross-sectional view of the stripline transmission line of this invention;
FIG. 2 is an isometric cross-sectional view of the stripline of FIG. 1; and
FIG. 3 is a cross-sectional view of another embodiment of the stripline transmission line.
DETAILED DESCRIPTION OF THE INVENTION Referring to FIGS. 1 and 2 there is shown a cross section and isometric cross section view of the stripline transmission line of this invention. Identical portions of FIGS. 1 and 2 have the same reference numbers. The stripline consists of a pair of flat metallic conductors l and II separated by an insulator 13. The insulator I3 is not mechanically secured to either of the metallic conductors and therefore the conductors are free to slide over the insulator.
The conductors l0 and 11 and the insulating strips l3, l5 and 16 are made in the form of flat, thin flexible strips arranged in the rectangular configuration shown. Covers 18 and 19 of flexible insulating material surround the conductors and insulating strips to hold them in the proper relationship. Covers l8 and 19 are joined at 21 and 22 to form a sealed enclosure for the stripline.
In FIG. 3 there is shown a cross-sectional view of another embodiment of this invention. Conductors 26 and 27 are separated by insulator 29 in the same manner as conductors l0 and II are separated by insulator 13. The insulating strips 15 and 16 of FIGS. 1 and 2 are not used and covers 31 and 32 are positioned directly adjacent conductors 26 and 27. Covers 31 and 32 are free to move relative to the conductors 26 and 27 and are joined at 33 and 34 to form a sealed enclosure for the stripline. Covers 31 and 32 may be formed of a polytetrafluoroethylene material. As an example, stripline having the features illustrated in FIGS. 1 to 3 has been constructed with a thickness of approximately 0.025 inch and a width of from 0.025 to 0.125 inch.
Since the elements of the stripline are free to move relative to each other when the line is bent to a small radius the elements of the stripline do not distort to form discontinuities in the transmission line. Thus the electrical characteristics of the line are not degraded when the line is used in equipment where it must be bent to a small radius.
It will be understood that the invention is not to be limited to the details given herein but that it may be modified within the scope of the appended claims.
The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
I claim:
I. A stripline, including in combination, a pair of bare electrical conductors positioned in parallel relationship, first insulator means slidably positioned between and in direct contact with said conductors, said conductors and said first insulator means being formed of flexible material of substantially equal width forming a rectangular configuration, and second insulator means disposed about said pair of conductors and said first insulator means in a restraining slidable engagement with said pair of conductors.
2. The stripline of claim 1 wherein, said second insulator means includes a pair of insulating strips each positioned adjacent and in direct contact with a separate one of said electrical conductors to position each of said electrical conductors between said first insulator means and one of said pair of insulating strips, said pair of insulating strips being in slidable engagement with said electrical conductors, said second insulator means further including cover means surrounding said electrical conductors, said first insulator means and said pair of insulating strips and holding the same in desired relationship.
3. The stripline of claim Z'wherein, said electrical conductors, said pair of insulating strips and said first insulator means are formed of flexible material of substantially equal width forming a rectangular configuration.
4. The stripline of claim 3 wherein, said first insulator means and said pair of insulating strips are formed of polytetrafluoroethylene.
Claims (4)
1. A stripline, including in combination, a pair of bare electrical conductors positioned in parallel relationship, first insulator means slidably positioned between and in direct contact with said conductors, said conductors and said first insulator means being formed of flexible material of substantially equal width forming a rectangular configuration, and second insulator means disposed about said pair of conductors and said first insulator means in a restraining slidable engagement with said pair of conductors.
2. The stripline of claim 1 wherein, said second insulator means includes a pair of insulating strips each positioned adjacent and in direct contact with a separate one of said electrical conductors to position each of said electrical conductors between said first insulator means and one of said pair of insulating strips, said pair of insulating strips being in slidable engagement with said electrical conductors, said second insulator means further including cover means surrounding said electrical conductors, said first insulator means and said pair of insulating strips and holding the same in desired relationship.
3. The stripline of claim 2 wherein, said electrical conductors, said pair of insulating strips and said first insulator means are formed of flexible material of substantially equal width forming a rectangular configuration.
4. The stripline of claim 3 wherein, said first insulator means and said pair of insulating strips are formed of polytetrafluoroethylene.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US85015169A | 1969-08-14 | 1969-08-14 |
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US3586757A true US3586757A (en) | 1971-06-22 |
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US850151A Expired - Lifetime US3586757A (en) | 1969-08-14 | 1969-08-14 | Flexible stripline transmission line |
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Cited By (32)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3941966A (en) * | 1974-05-22 | 1976-03-02 | Applied Materials, Inc. | RF Power transmission line |
US4382236A (en) * | 1980-05-12 | 1983-05-03 | Junkosha Co., Ltd. | Strip line cable using a porous, crystalline polymer dielectric tape |
FR2518303A1 (en) * | 1981-12-15 | 1983-06-17 | Erico | Flexible electric bus bar mfr. with insulated sheath - uses stack of conducting laminations with thermoplastic insulating strip laid along its faces and pressure welded |
US4490690A (en) * | 1982-04-22 | 1984-12-25 | Junkosha Company, Ltd. | Strip line cable |
US4716500A (en) * | 1985-10-18 | 1987-12-29 | Tektronix, Inc. | Probe cable assembly |
US4980659A (en) * | 1989-08-24 | 1990-12-25 | Raytheon Company | Microwave dual level transition |
US5065122A (en) * | 1990-09-04 | 1991-11-12 | Motorola, Inc. | Transmission line using fluroplastic as a dielectric |
WO1993019476A1 (en) * | 1992-03-25 | 1993-09-30 | Electric Power Research Institute, Inc. | Improved core-form transformer |
WO1994022148A1 (en) * | 1993-03-15 | 1994-09-29 | Ole Sahlholdt Goertz | Characteristic impedance corrected audio signal cable |
FR2730092A1 (en) * | 1995-01-26 | 1996-08-02 | Commissariat Energie Atomique | Medium or high voltage impulse transmission line flat cable connection |
US5837940A (en) * | 1995-05-15 | 1998-11-17 | Moncrieff; J. Peter | Conductive surface and method with nonuniform dielectric |
US5847324A (en) * | 1996-04-01 | 1998-12-08 | International Business Machines Corporation | High performance electrical cable |
US6323429B1 (en) * | 1997-07-08 | 2001-11-27 | Karl-Otto Platz | Electrical device, electrical appliance of lighting device |
US20020185298A1 (en) * | 2001-06-12 | 2002-12-12 | Fci Americas Technology, Inc. | Bus bar with frequency-filtering geometry |
GB2381651A (en) * | 1999-12-03 | 2003-05-07 | Methode Electronics Inc | A flat electrical cable without adhesive |
US6653570B1 (en) | 2001-04-11 | 2003-11-25 | David L. Elrod | Ribbon cable |
WO2004032205A2 (en) * | 2002-09-26 | 2004-04-15 | Freescale Semiconductor, Inc. | Current-carrying electronic component and method of manufacturing same |
US6841735B1 (en) * | 1996-04-03 | 2005-01-11 | Methode Electronics, Inc. | Flat cable and modular rotary anvil to make same |
US20050139379A1 (en) * | 2003-12-16 | 2005-06-30 | Friwo Mobile Power Gmbh | Flexible flat conductor with integrated output filter |
US20050247480A1 (en) * | 2004-05-04 | 2005-11-10 | Schulz Steven M | Self winding electric cord |
US20060180339A1 (en) * | 2005-02-15 | 2006-08-17 | Huffman Grover S | Design for linear broadband low frequency cable |
US20100294531A1 (en) * | 2007-06-13 | 2010-11-25 | Auto Kabel Managementgesellschaft Mbh | Motor Vehicle Power Cable |
US8622768B2 (en) | 2010-11-22 | 2014-01-07 | Andrew Llc | Connector with capacitively coupled connector interface |
US8622762B2 (en) | 2010-11-22 | 2014-01-07 | Andrew Llc | Blind mate capacitively coupled connector |
US8876549B2 (en) | 2010-11-22 | 2014-11-04 | Andrew Llc | Capacitively coupled flat conductor connector |
US8894439B2 (en) | 2010-11-22 | 2014-11-25 | Andrew Llc | Capacitivly coupled flat conductor connector |
US9048527B2 (en) | 2012-11-09 | 2015-06-02 | Commscope Technologies Llc | Coaxial connector with capacitively coupled connector interface and method of manufacture |
US9209510B2 (en) | 2011-08-12 | 2015-12-08 | Commscope Technologies Llc | Corrugated stripline RF transmission cable |
EP2880663A4 (en) * | 2012-07-30 | 2016-07-27 | Commscope Technologies Llc | Flexible electrical power cable |
US9419321B2 (en) | 2011-08-12 | 2016-08-16 | Commscope Technologies Llc | Self-supporting stripline RF transmission cable |
US9577305B2 (en) | 2011-08-12 | 2017-02-21 | Commscope Technologies Llc | Low attenuation stripline RF transmission cable |
US9601235B2 (en) | 2013-07-30 | 2017-03-21 | Commscope Technologies Llc | Hybrid cable with flat power conductors |
-
1969
- 1969-08-14 US US850151A patent/US3586757A/en not_active Expired - Lifetime
Cited By (41)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3941966A (en) * | 1974-05-22 | 1976-03-02 | Applied Materials, Inc. | RF Power transmission line |
US4382236A (en) * | 1980-05-12 | 1983-05-03 | Junkosha Co., Ltd. | Strip line cable using a porous, crystalline polymer dielectric tape |
FR2518303A1 (en) * | 1981-12-15 | 1983-06-17 | Erico | Flexible electric bus bar mfr. with insulated sheath - uses stack of conducting laminations with thermoplastic insulating strip laid along its faces and pressure welded |
US4490690A (en) * | 1982-04-22 | 1984-12-25 | Junkosha Company, Ltd. | Strip line cable |
US4716500A (en) * | 1985-10-18 | 1987-12-29 | Tektronix, Inc. | Probe cable assembly |
US4980659A (en) * | 1989-08-24 | 1990-12-25 | Raytheon Company | Microwave dual level transition |
US5065122A (en) * | 1990-09-04 | 1991-11-12 | Motorola, Inc. | Transmission line using fluroplastic as a dielectric |
US5508674A (en) * | 1992-03-25 | 1996-04-16 | Electric Power Research Institute, Inc. | Core-form transformer |
WO1993019476A1 (en) * | 1992-03-25 | 1993-09-30 | Electric Power Research Institute, Inc. | Improved core-form transformer |
US5393933A (en) * | 1993-03-15 | 1995-02-28 | Goertz; Ole S. | Characteristic impedance corrected audio signal cable |
WO1994022148A1 (en) * | 1993-03-15 | 1994-09-29 | Ole Sahlholdt Goertz | Characteristic impedance corrected audio signal cable |
FR2730092A1 (en) * | 1995-01-26 | 1996-08-02 | Commissariat Energie Atomique | Medium or high voltage impulse transmission line flat cable connection |
US5837940A (en) * | 1995-05-15 | 1998-11-17 | Moncrieff; J. Peter | Conductive surface and method with nonuniform dielectric |
US5847324A (en) * | 1996-04-01 | 1998-12-08 | International Business Machines Corporation | High performance electrical cable |
US6841735B1 (en) * | 1996-04-03 | 2005-01-11 | Methode Electronics, Inc. | Flat cable and modular rotary anvil to make same |
US6323429B1 (en) * | 1997-07-08 | 2001-11-27 | Karl-Otto Platz | Electrical device, electrical appliance of lighting device |
GB2381651A (en) * | 1999-12-03 | 2003-05-07 | Methode Electronics Inc | A flat electrical cable without adhesive |
GB2381651B (en) * | 1999-12-03 | 2004-01-14 | Methode Electronics Inc | Flat cable |
US6653570B1 (en) | 2001-04-11 | 2003-11-25 | David L. Elrod | Ribbon cable |
US6717054B2 (en) * | 2001-06-12 | 2004-04-06 | Fci Americas Technology, Inc. | Bus bar with frequency-filtering geometry |
US20020185298A1 (en) * | 2001-06-12 | 2002-12-12 | Fci Americas Technology, Inc. | Bus bar with frequency-filtering geometry |
WO2004032205A2 (en) * | 2002-09-26 | 2004-04-15 | Freescale Semiconductor, Inc. | Current-carrying electronic component and method of manufacturing same |
WO2004032205A3 (en) * | 2002-09-26 | 2004-07-01 | Motorola Inc | Current-carrying electronic component and method of manufacturing same |
US20050139379A1 (en) * | 2003-12-16 | 2005-06-30 | Friwo Mobile Power Gmbh | Flexible flat conductor with integrated output filter |
EP1544867A3 (en) * | 2003-12-16 | 2006-04-19 | Friwo Mobile Power GmbH | Flexible flat cable with integrated output filter |
US7173190B2 (en) | 2003-12-16 | 2007-02-06 | Friwo Mobile Power Gmbh | Flexible flat conductor with integrated output filter |
US20050247480A1 (en) * | 2004-05-04 | 2005-11-10 | Schulz Steven M | Self winding electric cord |
US20060180339A1 (en) * | 2005-02-15 | 2006-08-17 | Huffman Grover S | Design for linear broadband low frequency cable |
US7304246B2 (en) * | 2005-02-15 | 2007-12-04 | Grover Scott Huffman | Design for linear broadband low frequency cable |
US20100294531A1 (en) * | 2007-06-13 | 2010-11-25 | Auto Kabel Managementgesellschaft Mbh | Motor Vehicle Power Cable |
US8622768B2 (en) | 2010-11-22 | 2014-01-07 | Andrew Llc | Connector with capacitively coupled connector interface |
US8622762B2 (en) | 2010-11-22 | 2014-01-07 | Andrew Llc | Blind mate capacitively coupled connector |
US8876549B2 (en) | 2010-11-22 | 2014-11-04 | Andrew Llc | Capacitively coupled flat conductor connector |
US8894439B2 (en) | 2010-11-22 | 2014-11-25 | Andrew Llc | Capacitivly coupled flat conductor connector |
US9209510B2 (en) | 2011-08-12 | 2015-12-08 | Commscope Technologies Llc | Corrugated stripline RF transmission cable |
US9419321B2 (en) | 2011-08-12 | 2016-08-16 | Commscope Technologies Llc | Self-supporting stripline RF transmission cable |
US9577305B2 (en) | 2011-08-12 | 2017-02-21 | Commscope Technologies Llc | Low attenuation stripline RF transmission cable |
EP2880663A4 (en) * | 2012-07-30 | 2016-07-27 | Commscope Technologies Llc | Flexible electrical power cable |
US10002688B2 (en) | 2012-07-30 | 2018-06-19 | Commscope Technologies Llc | Flexible electrical power cable |
US9048527B2 (en) | 2012-11-09 | 2015-06-02 | Commscope Technologies Llc | Coaxial connector with capacitively coupled connector interface and method of manufacture |
US9601235B2 (en) | 2013-07-30 | 2017-03-21 | Commscope Technologies Llc | Hybrid cable with flat power conductors |
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