Textiles: spinning – twisting – and twining – Strand structure – Plied
Reexamination Certificate
2001-09-07
2002-07-02
Worrell, Danny (Department: 3765)
Textiles: spinning, twisting, and twining
Strand structure
Plied
C057S231000, C057S234000
Reexamination Certificate
active
06412265
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a twisted flat cable used for internal wiring of electronic equipment such as computers.
2. Prior Art
A flat cable used for internal wiring of electronic equipment such as computers is prepared in such that conductors are arranged in parallel to each other, and they are insulated in accordance with a trend of downsizing as well as weight reduction for electronic equipment for the purpose of cut-back for wiring such as space-saving wiring or of cut-back for mounting a flat cable, and maintenance and inspecting operations therefor.
Merits of such flat cable as mentioned above are enumerated in the following items (1) to (6).
(1) It is possible to omit bundling insulated wire cores.
(2) It is possible to elevate a packaging density of electronic parts or the like.
(3) There is little fear of erroneous wiring, besides maintenance and inspection are also easy.
(4) There is sufficient flexibility so that wiring is easy.
(5) It is possible to reduce the number of steps for terminal processing.
(6) It is easy to correspond to automation for cutting a cable or mounting a connector.
In
FIGS. 1
,
2
and
3
, a twisted flat cable being a type of flat cables are shown, respectively, wherein
FIG. 1
is a plan view showing a conventional twisted flat cable;
FIG. 2
is a sectional view taken along the line A—A of the twisted flat cable shown in
FIG. 1
; and
FIG. 3
is a plan view showing a plastic tape used in the twisted flat cable shown in FIG.
1
.
A twisted flat cable
51
shown in
FIG. 1
is composed of a plurality of insulated wire cores
52
arranged in parallel to each other wherein molten sections
53
each prepared by melting all the adjacent insulated wire cores
52
with each other are alternately disposed in the longitudinal direction thereof with a predetermined interval with respect to pair-twisted sections
54
each prepared by pair-twisting each adjacent pairs of insulated wire cores among adjacent insulated wire cores
52
with each other.
A plastic tape
55
is welded (laminated) on either surface (the under surface in
FIG. 2
) of the arranged insulated wire cores
52
over the whole length thereof. An adhesive layer has been prepared on either surface of the plastic tape
55
(the upper surface in FIG.
2
). Lamination is made after bonding the insulated wire cores
52
to the adhesive layer.
In the above-mentioned twisted flat cable
51
, however, since the plastic tape
55
has been disposed over the whole length of the twisted flat cable, the plastic tape
55
does not enter flexibly into a gap defined in between pair-twisted sections
54
, so that there is such a tendency that the pair-twisted sections
54
are collapsed in a laminating step. Furthermore, since the plastic tape
55
has been applied to the whole surface of the twisted flat cable
51
, there has been such a tendency that dielectric constant thereof becomes higher between insulated wire cores than that of a product without lamination processing.
Thus, there has been such a problem that impedance decreases in a pair each of the molten sections and the pair-twisted sections
54
.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to solve the above-described problems, and to provide a twisted flat cable, which exhibits flexibility and accompanies with no decrease of impedance in laminating step.
In order to achieve the above-described object, a twisted flat cable of the present invention composed of a plurality of insulated wire cores arranged in parallel to each other wherein molten sections each prepared by melting all the adjacent insulated wire cores with each other are alternately disposed in the longitudinal direction thereof with respect to pair-twisted sections each prepared by pair-twisting each adjacent pairs of insulated wire cores among adjacent insulated wire cores with each other, comprises a plastic tape having an adhesive layer on either surface thereof as well as having a plurality of perforations defined thereon being laminated on the insulated wire cores arranged in parallel to each other so as to be in contact with the adhesive layer.
According to the present invention, a plurality of perforations has been defined on a plastic tape to be laminated on insulated wire cores. Accordingly, intrusions of the plastic tape in between each of pair-twisted sections are elevated in laminating step of the plastic tape. As a result, collapses in pair-twisted sections decrease, and in addition, portions of a tape material corresponding to perforations defined on the plastic tape are replaced by air, so that dielectric constant between conductors of the insulated wire cores decreases, whereby decrease in impedance can be reduced.
REFERENCES:
patent: 587764 (1897-08-01), Short
patent: 1209096 (1916-12-01), Williamson
patent: 3695027 (1972-10-01), Copp
patent: 4439256 (1984-03-01), Meserve
patent: 4455818 (1984-06-01), Sugimoto et al.
patent: 4529837 (1985-07-01), Borden
patent: 4947637 (1990-08-01), Royet et al.
patent: 6270598 (2001-08-01), Kasahara et al.
Mizushima Satoshi
Yamamoto Tetsuhiro
Hitachi Cable Ltd.
Worrell Danny
LandOfFree
Twisted flat cable does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Twisted flat cable, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Twisted flat cable will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2865147