Patent Application
20110011638
Shielding is used a variety of cables to reduce electrical interference that could affect a signal travelling through the cable. The shielding also helps prevent the signal from radiating from the cable and interfering with other devices. One such type of shielding includes a layer of aluminum or other shielding material (such as silver or copper) laminated on a separating layer, such as a plastic, e.g., polyethylene terephthalate (“PET”) or polypropylene (“PP”). This type of shielding, which combines layers of shielding material and separating layers, is often referred to as either “foil,” “laminated tape,” “shielding tape,” “shielding laminate tape,” and combinations or variations thereof. In some cables, such as coaxial cables, multiple layers of shielding tape are sometimes employed.
When used, shielding tape is wrapped about the longitudinal axis of a cable, overlapping itself to some degree to ensure a proper level of shielding. In some shielded cables, it is desirable to be able to detect the outer edge of the overlapping shielding tape. In coaxial cables, for example, a portion of the outer layer of shielding tape must be removed to allow an installer to expose, and peel back, a layer of aluminum braiding before compressing or crimping a connector (such as an F-type connector) onto the end of the cable. Conventional shielding tape, however, is of uniform color, making the outer edge of the overlap difficult and time-consuming to locate.
The present invention comprises a shielding tape comprising at least one shielding layer, at least one separator layer, a first (inner) edge, and a second (outer) edge. The shielding tape further includes an indicator extending along at least a portion of the outer edge. The indicator is for identifying the outer edge when the outer edge overlaps the inner edge when the shielding tape is positioned onto a cable. Alternatively, both edges may have an indicator.
The present invention also includes a cable having a center conductor and an outer shielding tape as described above that surrounds the center conductor. The shielding tape may surround the conductor directly (i.e., there are no intervening structures between the conductor and the tape) or indirectly (i.e., there are one or more intervening structures between the conductor and the tape, such as a dielectric, braiding, or other shielding tape). The present invention makes it easy to locate the outer edge of the shielding tape for an installer wishing to remove at least some of the shielding tape before crimping or compressing a connector onto the end of a cable.
Turning now to the Figures, where the purpose is to describe a preferred embodiment of the invention and not to limit same,
The shielding tape 100 (also referred to herein as “outer foil”) is wrapped about the longitudinal axis of the cable 10 with the inner edge (not shown) of shielding tape 100 in direct contact with the braid 50, and the outer edge 102 (denoted by the label “overlap” in
The indicator may be visual, tactile, or both. The indicator may be continuous, as shown, or intermittent. A shielding tape in accordance with the present invention may include any number of separate indicators.
The preferred indicator 104 according to the present invention is visual and may be any size, shape, color, or design. In the preferred embodiment, the indicator 104 is a continuous solid colored line about 1-2 mm wide. The visual indicator 104 is of a different color than the rest of the shielding tape to help identify the location of the outer edge 102. The visual indicator 104 may also be intermittently placed along the outer edge 102 and formed in any suitable manner. The indicator 104 in
A tactile indicator according to the present invention may include any number and combination of tactile indicators to help identify the outer edge of the laminated foil tape, such as raised portions or indentations in the tape and/or a sawtooth or other pattern cut along the outer edge of the tape. The tactile indicator may also serve as a visual indicator (e.g., in the case of a pattern cut in the edge of the outer edge).
A preferred cable with which shielding tape 100 is used is a coaxial cable 10 as shown in
The shielding tape of the present invention may be used in conjunction with any other type of shielded cable, such as shielded twisted-pair cabling. The shielding tape of the present invention may also be used to surround any type of conductor, insulator, or other component of a shielded cable. For example, the shielding tape may surround a conductor directly (i.e., there are no intervening structures between the conductor and the tape) or indirectly (i.e., there are one or more intervening structures between the conductor and the tape, such as a dielectric, braiding, or other shielding).
Having thus described preferred embodiments of the invention, other variations and embodiments that do not depart from the spirit of the invention will become apparent to those skilled in the art. The scope of the present invention is thus not limited to any particular embodiment, but is instead set forth in the appended claims and the legal equivalents thereof. Unless expressly stated in the written description or claims, the steps of any method recited in the claims may be performed in any order capable of yielding the desired result.
This nonprovisional utility application claims priority to U.S. Provisional Patent Application No. 61/226,249, filed Jul. 16, 2009 titled “Shielding Tape With Edge Indicator,” the disclosure of which is fully incorporated herein by reference for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 61226249 | Jul 2009 | US |
