FREE AIR FIRE ALARM CABLE

Abstract

An electric wire includes a metal conductor, a heat stable tape, wherein the tape is in direct contact with the conductor, wherein the tape can withstand temperatures of at least about 1850 F., a high temperature fiberglass layer, wherein the fiberglass layer is in direct contact with the tape, and an insulating sheath around the fiberglass layer, wherein the wire has no conduit protection.

Claims

1. A free air fire alarm cable comprising: a metal conductor, wherein the conductor has an AWG of 12 or smaller, wherein the metal conductor has a top and a bottom; a first mica layer in direct contact with the metal conductor, wherein the first mica layer has a first edge and a second edge, wherein the first mica layer is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge on the bottom of the metal conductor; a first high tensile, high temperature fiberglass layer clockwise spiral-wrapped directly onto the first mica layer, the first fiberglass layer having a top and a bottom; a second mica layer in direct contact with the first fiberglass layer, wherein the second mica layer has a first edge and a second edge, wherein the second mica layer is folded around the first fiberglass layer such that the first edge of the second mica layer and second edge of the second mica layer are substantially parallel to one another and the first edge of the second mica layer overlaps the second edge of the second mica layer on the top of the first fiberglass layer; a second high tensile, high temperature fiberglass layer counterclockwise spiral-wrapped directly onto the second mica layer; and a insulating sheath around the second fiberglass layer, wherein the cable has no conduit.

2. An electric wire comprising: a metal conductor; a heat stable tape, wherein the tape is in direct contact with the conductor, wherein the tape can withstand temperatures of at least about 1850 F.; a high temperature fiberglass layer, wherein the fiberglass layer is in direct contact with the tape; and an insulating sheath around the fiberglass layer, wherein the wire has no conduit protection.

3. The wire of claim 2, wherein the tape has a first edge and a second edge, wherein the tape is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge.

4. The wire of claim 3, wherein the fiberglass layer is braided over the tape.

5. The wire of claim 4, wherein the tape is mica tape.

6. The wire of claim 3, wherein the fiberglass layer is a two directional serve layer.

7. The wire of claim 2, wherein the tape is folded around the conductor.

8. The wire of claim 7, wherein the tape is mica and is a first mica layer, the high temperature fiberglass layer is a first fiberglass layer, the metal conductor has a top and a bottom, the wire further comprising: the first mica layer having a first edge and a second edge, wherein the first mica layer is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge on the bottom of the metal conductor; the first high temperature fiberglass layer clockwise spiral-wrapped directly onto the first mica layer, the first fiberglass layer having a top and a bottom; a second mica layer in direct contact with the first fiberglass layer, wherein the second mica layer has a first edge and a second edge, wherein the second mica layer is folded around the first fiberglass layer such that the first edge of the second mica layer and second edge of the second mica layer are substantially parallel to one another and the first edge of the second mica layer overlaps the second edge of the second mica layer on the top of the first fiberglass layer; and a second high temperature fiberglass layer counterclockwise spiral-wrapped directly onto the second mica layer, wherein the insulating sheath is around the second fiberglass layer.

9. The wire of claim 8, wherein the conductor has an AWG of 12 or smaller.

10. A plenum-rated electric wire comprising: a metal conductor; a heat stable tape layer, wherein the tape layer is in direct contact with the conductor, wherein the tape layer can withstand temperatures of at least about 1850 F.; a high temperature fiberglass layer, wherein the fiberglass layer is in direct contact with the tape, wherein there is no silicone between the tape and the fiberglass layer; and a plenum-rated insulating sheath around the fiberglass layer.

11. The wire of claim 10, wherein the tape has a first edge and a second edge, wherein the tape is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge.

12. The wire of claim 11, wherein the fiberglass layer is braided over the tape.

13. The wire of claim 12, wherein the tape is mica tape.

14. The wire of claim 11, wherein the fiberglass layer is a two directional serve layer.

15. The wire of claim 10, wherein the tape is folded around the conductor.

16. The wire of claim 15, wherein the tape is mica and is a first mica layer, the high temperature fiberglass layer is a first fiberglass layer, the metal conductor has a top and a bottom, the wire further comprising: the first mica layer having a first edge and a second edge, wherein the first mica layer is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge on the bottom of the metal conductor; the first high temperature fiberglass layer clockwise spiral-wrapped directly onto the first mica layer, the first fiberglass layer having a top and a bottom; a second mica layer in direct contact with the first fiberglass layer, wherein the second mica layer has a first edge and a second edge, wherein the second mica layer is folded around the first fiberglass layer such that the first edge of the second mica layer and second edge of the second mica layer are substantially parallel to one another and the first edge of the second mica layer overlaps the second edge of the second mica layer on the top of the first fiberglass layer; and a second high temperature fiberglass layer counterclockwise spiral-wrapped directly onto the second mica layer, wherein the insulating sheath is around the second fiberglass layer.

17. The wire of claim 16, wherein the wire further comprises a plenum-rated jacket around the insulating sheath, wherein the wire has no conduit protection.

18. The wire of claim 17, wherein the conductor has an AWG of 12 or smaller.

Description

III. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present teachings are described hereinafter with reference to the accompanying drawings.

[0034] FIG. 1 shows a cross-sectional view of the wire with an insulating sheath;

[0035] FIG. 2 shows a cross-sectional view of the plenum rated wire with an insulating sheath and jacket;

[0036] FIG. 3 shows a cross-sectional view of another embodiment of the wire;

[0037] FIG. 4A shows a cross-sectional view of the metal conductor of FIG. 3 and the first mica layer folded around the conductor;

[0038] FIG. 4B shows a perspective view of the first fiberglass layer wrapped clockwise around the first mica layer of FIG. 3;

[0039] FIG. 4C shows a cross-sectional view of the first mica layer, the first fiberglass layer, and the second mica layer folded around the first fiberglass layer of FIG. 3;

[0040] FIG. 4D shows a perspective view of the second fiberglass layer wrapped counterclockwise around the second mica layer of FIG. 3;

[0041] FIG. 5A shows a perspective view of another embodiment of the wire with a fiberglass layer braided around the mica layer;

[0042] FIG. 5B shows a perspective view of another embodiment of the wire with a two directional serve fiberglass layer around the mica layer;

[0043] FIG. 6 shows a cutaway perspective view of the wire of FIG. 2;

[0044] FIG. 7 shows a cutaway perspective view of the wire of FIG. 1;

[0045] FIG. 8 shows a cutaway perspective view of the wire of FIG. 3;

[0046] FIG. 9 shows a cutaway perspective view of the wire of FIG. 5A;

[0047] FIG. 10 shows a cutaway perspective view of the wire of FIG. 5B;

[0048] FIG. 11 shows a cross-sectional view of the wire of FIG. 1 with a jacket; and

[0049] FIG. 12 shows a cross sectional view of the FIG. 3 with a jacket.

IV. DETAILED DESCRIPTION

[0050] In reference to the FIGS. 1, 5A, 5B, 7, 9, 10, and 11, a wire 100, designed for a free air fire alarm cable, is shown. The wire 100 has a metal conductor 102, with a heat stable tape layer 104 folded around the conductor 102. A high tensile, high temperature fiberglass layer 106 is wrapped around the heat tape layer 104. Around the fiberglass layer 106 is an insulating sheath 108. The heat stable tape layer 104, which is a high temperature adhesive that can withstand temperatures of at least 1850 F. (1010 C.), is in direct contact with the conductor 102. The heat stable tape layer 104 can be mica, and the folded nature of the heat stable tape layer 104 creates a sleeve for the conductor 102, which allows some movement of the conductor 102. The fiberglass layer 106 is in direct contact with the heat stable tape layer 104, and operates as a strength member to prevent buckling of the conductor 102. The wire 100 does not have a conduit, and will be held with rings or straps from the rafters in the ceiling of the building after installation. In one aspect, the conductor 102 is copper and has an AWG of 12 or smaller. With particular reference to FIGS. 5A and 9, the fiberglass layer 506 can be a braided layer. With particular reference to FIGS. 5B and 10, the fiberglass layer 508 can be a two directional serve layer. With reference to FIG. 7, the heat stable tape layer 104 has a first edge 402 and a second edge 404, wherein when the heat stable tape layer 104 is folded around the conductor 102, the first edge 402 slightly overlaps the second 404. With reference to FIG. 11, wire 100 can have a jacket 1100 around the insulating sheath 108.

[0051] With reference to FIGS. 2, 5A, 5B, 6, 9, and 10, another aspect of the present teachings shows a plenum-rated wire 200 is shown, having a metal conductor 202, with a heat stable tape layer 204 folded around the conductor 202. A high tensile, high temperature fiberglass layer 206 is wrapped around the heat tape layer 204. Around the fiberglass layer 206 is a plenum-rated insulating sheath 208, and around the sheath 208 is a plenum-rated jacket 210. The heat stable tape layer 204, which is a high temperature adhesive that can withstand temperatures of at least 1850 F. (1010 C.), is in direct contact with the conductor 202. The heat stable tape layer 204 can be mica, and the folded nature of the heat stable tape layer 204 creates a sleeve for the conductor 202, which allows some movement of the conductor 202. The fiberglass layer 206 is in direct contact with the heat stable tape layer 204, and operates as a strength member to prevent buckling of the conductor 202. The wire 200 has no silicone between the heat stable tape layer 204 and the fiberglass layer 206. The wire 200 does not have a conduit, and will be held with rings or straps from the rafters in the ceiling of the building after installation. In one aspect, the conductor 202 is copper and has an AWG of 12 or smaller. With particular reference to FIGS. 5A and 9, the fiberglass layer 506 can be a braided layer. With particular reference to FIGS. 5B and 10, the fiberglass layer 508 can be a two directional serve layer. With reference to FIG. 6, the heat stable tape layer 204 has a first edge 402 and a second edge 404, wherein when the heat stable tape layer 204 is folded around the conductor 202, the first edge 402 slightly overlaps the second 404.

[0052] With reference to FIGS. 3, 4A, 4B, 4C, 4D, 8, and 12, a wire 300, designed for a free air fire alarm cable, is shown. The wire 300 has a metal conductor 302 having a top and a bottom (shown but not referenced). A first mica layer 304 is in direct contact with the metal conductor 302, and is folded around the metal conductor 302. The first mica layer 304 has a first edge 402 and a second edge 400 (shown in FIG. 4A), wherein the first mica layer 304 is folded around the metal conductor 302 in such a way that the edges 400, 402 are substantially parallel with one another, and the first edge 402 slightly overlaps the second edge 400 at the top of the metal conductor 302. A first high tensile, high temperature fiberglass layer 306 is in direct contact with the first mica layer 304, wherein the first fiberglass layer has a top and a bottom (shown but not referenced). The first fiberglass layer 306 is clockwise spiral-wrapped around the first mica layer 304 (as shown in FIG. 4B). A second mica layer 308 is in direct contact with the first fiberglass layer 304, wherein the second mica layer 308 has a first edge 404 and a second edge 406. The second mica layer 308 is folded around the first fiberglass layer 306 in such a way that the edges 404, 406 are substantially parallel with one another, and the first edge 404 slightly overlaps the second edge 406 at the bottom of the first fiberglass layer 306 (shown in FIG. 4C). A second high tensile, high temperature fiberglass layer 310 is in direct contact with the second mica layer 308. The second fiberglass layer 310 is counterclockwise spiral-wrapped around the second mica layer 308 (as shown in FIG. 4D). An insulating sheath 312 is on the outside of the second fiberglass layer 310 as shown in FIGS. 3 and 8. With reference to FIG. 12, wire 300 can have a jacket 1200 around the insulating sheath 312.

[0053] With reference now to FIG. 2, it is to be understood that the multiple mica layers as described in FIGS. 3, 4A-4D, and 8, can be used in the plenum rated wire 200 of FIG. 2. With reference now to FIG. 1, it is to be understood that the multiple mica layers as described in FIGS. 3, 4A-4D, and 8, can be used in the wire 100 of FIG. 1.

EXAMPLE

[0054] In a UL 2196 test, the wire 200 was tested, and the leakage rates were between 0.44 mA and 9.34 mA and the circuit continuities were all still intact.

[0055] In one example a wire has an 18 AWG solid conductor with a 0.022 inch (0.556 mm) insulation thickness, a nominal jacket thickness of 0.022 inch (0.556 mm), a nominal outer diameter of 0.240 inch (6.10 mm), a nominal capacitance of 11.17 pF/FT (36.65 pF/m), and a characteristic impedance at 1 MHz of 140.7 ohms.

[0056] In one example a wire has an 16 AWG solid conductor with a 0.022 inch (0.556 mm) insulation thickness, a nominal jacket thickness of 0.022 inch (0.556 mm), a nominal outer diameter of 0.248 inch (6.30 mm), a nominal capacitance of 12.39 pF/FT (40.65 pF/m), and a characteristic impedance at 1 MHz of 114.6 ohms.

[0057] In one example a wire has an 14 AWG solid conductor with a 0.022 inch (0.556 mm) insulation thickness, a nominal jacket thickness of 0.022 inch (0.556 mm), and a nominal outer diameter of 0.252 inch (6.40 mm).

[0058] In one example a wire has an 14 AWG 7-strand conductor with a 0.022 inch (0.556 mm) insulation thickness, a nominal jacket thickness of 0.022 inch (0.556 mm), a nominal outer diameter of 0.263 inch (6.68 mm), a nominal capacitance of 14.76 pF/FT (48.43 pF/m), and a characteristic impedance at 1 MHz of 106.7 ohms.

[0059] In one example a wire has an 12 AWG solid conductor with a 0.022 inch (0.556 mm) insulation thickness, a nominal jacket thickness of 0.022 inch (0.556 mm), and a nominal outer diameter of 0.272 inch (6.91 mm).

[0060] In one example a wire has an 12 AWG 7-strand conductor with a 0.022 inch (0.556 mm) insulation thickness, a nominal jacket thickness of 0.022 inch (0.556 mm), a nominal outer diameter of 0.289 inch (7.34 mm), a nominal capacitance of 15.93 pF/FT (52.26 pF/m), and a characteristic impedance at 1 MHz of 99.1 ohms.

[0061] It is to be understood that the wire (using a key as follows: J=jacket; S=insulating sheath; F.sup.C=clockwise-wrapped fiberglass layer; F.sup.CC=counterclockwise-wrapped fiberglass layer; F.sup.B=braided fiberglass layer; F.sup.T=two directional serve fiberglass layer; J.sup.P=plenum rated jacket; S.sup.I=plenum rated insulating sheath; M=mica layer; C=conductor) can be made in at least the following ways: CMF.sup.BS; CMF.sup.BSJ; CMF.sup.TS; CMF.sup.TSJ; CMF.sup.BMF.sup.BS; CMF.sup.BMF.sup.BSJ; CMF.sup.BMF.sup.TS; CMF.sup.BMF.sup.TSJ; CMF.sup.TMF.sup.TS; CMF.sup.TMF.sup.TSJ; CMF.sup.TMF.sup.BS; CMF.sup.TMF.sup.BSJ; CMF.sup.BS.sup.P; CMF.sup.BS.sup.PJ.sup.P; CMF.sup.TS.sup.P; CMF.sup.TS.sup.PJ.sup.P; CMF.sup.BMF.sup.BS.sup.P; CMF.sup.BMF.sup.BS.sup.PJ.sup.P; CMF.sup.BMF.sup.TS.sup.P; CMF.sup.BMF.sup.TS.sup.PJ.sup.P; CMF.sup.TMF.sup.TS.sup.P; CMF.sup.TMF.sup.TS.sup.PJ.sup.P; CMF.sup.TMF.sup.BS.sup.P; CMF.sup.TMF.sup.BS.sup.PJ.sup.P; CMF.sup.CMF.sup.CCS; CMF.sup.CCMF.sup.CS; CMF.sup.CMF.sup.CCSJ; CMF.sup.CCMF.sup.CSJ; CMF.sup.CMF.sup.CCS.sup.P; CMF.sup.CCMF.sup.CS.sup.P; CMF.sup.CMF.sup.CCS.sup.PJ.sup.P; CMF.sup.CCMF.sup.CS.sup.PJ.sup.P; CMF.sup.BSJ.sup.P; CMF.sup.BS.sup.PJ; CMF.sup.TSJ.sup.P; CMF.sup.TS.sup.PJ; CMF.sup.BMF.sup.BSJ.sup.P; CMF.sup.BMF.sup.BS.sup.PJ; CMF.sup.BMF.sup.TSJ.sup.P; CMF.sup.BMF.sup.TS.sup.PJ; CMF.sup.TMF.sup.TSJ.sup.P; CMF.sup.TMF.sup.TS.sup.PJ; CMF.sup.TMF.sup.BSJ.sup.P; CMF.sup.TMF.sup.BS.sup.PJ; CMF.sup.CMF.sup.CCSJ.sup.P; CMF.sup.CMF.sup.CCS.sup.PJ; CMF.sup.CCMF.sup.CS.sup.PJ; CMF.sup.CCMF.sup.CSJ.sup.P.

[0062] The embodiments have been described, hereinabove. It will be apparent to those skilled in the art that the above methods and apparatuses may incorporate changes and modifications without departing from the general scope of the present teachings. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. Although the description above contains much specificity, this should not be construed as limiting the scope of the present teachings, but as merely providing illustrations of some of the embodiments of the present teachings. Various other embodiments and ramifications are possible within its scope.

[0063] Furthermore, notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present teachings are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0064] Clause 1A free air fire alarm cable comprising a metal conductor, wherein the conductor has an AWG of 12 or smaller, wherein the metal conductor has a top and a bottom; a first mica layer in direct contact with the metal conductor, wherein the first mica layer has a first edge and a second edge, wherein the first mica layer is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge on the bottom of the metal conductor; a first high tensile, high temperature fiberglass layer clockwise spiral-wrapped directly onto the first mica layer, the first fiberglass layer having a top and a bottom; a second mica layer in direct contact with the first fiberglass layer, wherein the second mica layer has a first edge and a second edge, wherein the second mica layer is folded around the first fiberglass layer such that the first edge of the second mica layer and second edge of the second mica layer are substantially parallel to one another and the first edge of the second mica layer overlaps the second edge of the second mica layer on the top of the first fiberglass layer; a second high tensile, high temperature fiberglass layer counterclockwise spiral-wrapped directly onto the second mica layer; and a insulating sheath around the second fiberglass layer, wherein the cable has no conduit.

[0065] Clause 2An electric wire comprising a metal conductor; a heat stable tape, wherein the tape is in direct contact with the conductor, wherein the tape can withstand temperatures of at least about 1850 F. (1010 C.); a high temperature fiberglass layer, wherein the fiberglass layer is in direct contact with the tape; and an insulating sheath around the fiberglass layer, wherein the wire has no conduit protection.

[0066] Clause 3The wire of clause 2, wherein the tape has a first edge and a second edge, wherein the tape is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge.

[0067] Clause 4The wire of clauses 2 or 3, wherein the fiberglass layer is braided over the tape.

[0068] Clause 5The wire of clauses 2-4, wherein the tape is mica tape.

[0069] Clause 6The wire of clauses 2, 3, or 5, wherein the fiberglass layer is a two directional serve layer.

[0070] Clause 7The wire of clauses 2-6, wherein the tape is folded around the conductor.

[0071] Clause 8The wire of clauses 2, 3, 5, or 7, wherein the tape is mica and is a first mica layer, the high temperature fiberglass layer is a first fiberglass layer, the metal conductor has a top and a bottom, the wire further comprising the first mica layer having a first edge and a second edge, wherein the first mica layer is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge on the bottom of the metal conductor; the first high temperature fiberglass layer clockwise spiral-wrapped directly onto the first mica layer, the first fiberglass layer having a top and a bottom; a second mica layer in direct contact with the first fiberglass layer, wherein the second mica layer has a first edge and a second edge, wherein the second mica layer is folded around the first fiberglass layer such that the first edge of the second mica layer and second edge of the second mica layer are substantially parallel to one another and the first edge of the second mica layer overlaps the second edge of the second mica layer on the top of the first fiberglass layer; and a second high temperature fiberglass layer counterclockwise spiral-wrapped directly onto the second mica layer, wherein the insulating sheath is around the second fiberglass layer.

[0072] Clause 9The wire of clauses 2-8, wherein the conductor has an AWG of 12 or smaller.

[0073] Clause 10A plenum-rated electric wire comprising a metal conductor; a heat stable tape layer, wherein the tape layer is in direct contact with the conductor, wherein the tape layer can withstand temperatures of at least about 1850 F. (1010 C.); a high temperature fiberglass layer, wherein the fiberglass layer is in direct contact with the tape, wherein there is no silicone between the tape and the fiberglass layer; and a plenum-rated insulating sheath around the fiberglass layer.

[0074] Clause 11The wire of clause 10, wherein the tape has a first edge and a second edge, wherein the tape is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge.

[0075] Clause 12The wire of clauses 10 or 11, wherein the fiberglass layer is braided over the tape.

[0076] Clause 13The wire of clauses 10-12, wherein the tape is mica tape.

[0077] Clause 14The wire of clauses 10, 11, or 13, wherein the fiberglass layer is a two directional serve layer.

[0078] Clause 15The wire of clauses 10-14, wherein the tape is folded around the conductor.

[0079] Clause 16The wire of clauses 10, 11, 13, or 15, wherein the tape is mica and is a first mica layer, the high temperature fiberglass layer is a first fiberglass layer, the metal conductor has a top and a bottom, the wire further comprising the first mica layer having a first edge and a second edge, wherein the first mica layer is folded around the metal conductor such that the first edge and second edge are substantially parallel to one another and the first edge overlaps the second edge on the bottom of the metal conductor; the first high temperature fiberglass layer clockwise spiral-wrapped directly onto the first mica layer, the first fiberglass layer having a top and a bottom; a second mica layer in direct contact with the first fiberglass layer, wherein the second mica layer has a first edge and a second edge, wherein the second mica layer is folded around the first fiberglass layer such that the first edge of the second mica layer and second edge of the second mica layer are substantially parallel to one another and the first edge of the second mica layer overlaps the second edge of the second mica layer on the top of the first fiberglass layer; and a second high temperature fiberglass layer counterclockwise spiral-wrapped directly onto the second mica layer, wherein the insulating sheath is around the second fiberglass layer.

[0080] Clause 17The wire of clauses 10-16, wherein the wire further comprises a plenum-rated jacket around the insulating sheath, wherein the wire has no conduit protection.

[0081] Clause 18The wire of clauses 10-17, wherein the conductor has an AWG of 12 or smaller.