Patent ID: 6337441
Filing Date: 2002-01-08
Classification: H01B

Abstract:
A shielded multi-core cable manufacturing method, comprising the steps of:preparing (a) two insulator-covered wires S1 and S2 each having a conductive core A embedded in a first cylindrical insulator rod B having an outer diameter &phgr;B2 in a manner to be concentric therewith, (b) two second cylindrical insulator rods C1 and C2 each having an outer diameter &phgr;C2 equal to or not equal to the outer diameter &phgr;B2 of the first cylindrical insulator B, and (c) a cylindrical conductive pipe E having an inner diameter &phgr;E1 larger than twice the outer diameter &phgr;B2 of the first cylindrical insulator rod B but smaller than a sum of twice the outer diameter &phgr;B2 of the first cylindrical insulator rod B and the outer diameter &phgr;C2 of the second cylindrical insulator rods C1 and C2, the inner diameter &phgr;E1 of said cylindrical conductive pipe E being defined through utilization of the outer diameter &phgr;B2 of the first cylindrical insulator rod B of said two insulator-covered wires S1 and S2 and the outer diameter &phgr;C2 of the second cylindrical insulator rods C1 and C2; inserting said two insulator-covered wires S1 and S2 and said two second cylindrical insulator rods C1 and C2 into said cylindrical conductive pipe E alternately arranged about the center axis thereof; and drawing said cylindrical conductive pipe E with said two insulator-covered wires S1 and S2 and said two second cylindrical insulator rods C1 and C2 inserted therein, thereby obtaining a shielded multi-core cable of a construction in which (a) two first insulator rods B1â€² and B2â€², formed respectively from the first cylindrical insulator rods B of said insulator-covered wires S1 and S2 and having respectively embedded therein two conductive core A1â€² and A2â€² which are respectively of the conductive core A of the insulator-covered wire S1 and S2, and (b) two second insulator rods C1â€² and C2â€², formed respectively from said two second cylindrical insulator rods C1 and C2, are tightly received in a cylindrical shielding conductive pipe Eâ€² being formed from said cylindrical conductive pipe E so that said two conductive cores A1â€² and A2â€² are held therein about the center axis thereof, said cylindrical shielding conductive pipe Eâ€² having inner and outer diameters smaller than those of said cylindrical conductive pipe E; wherein (i) the line joining the centers of the conductive cores A1â€² and A2â€² passes through the center of the cylindrical shielding conductive pipe Eâ€², and hence the conductive cores A1â€² and A2â€² are symmetrical in terms of position and configuration with respect to a line that crosses at right angles the line joining the centers of the conductive cores A1â€² and A2â€² and passes through the center of the cylindrical shielding conductive pipe Eâ€², (ii) the first insulator rods B1â€² and B2â€² are disposed with their inner sharp edges held along the center of the cylindrical shielding conductive pipe Eâ€², and they are exactly or substantially symmetrical in terms of position and configuration with respect to the line that crosses at right angles the line joining the centers of the conductive cores A1â€² and A2â€² and passes through the center of the cylindrical conductive pipe Eâ€², (iii) the second insulator rods C1â€² and C2â€² are disposed with their inner sharp edges held along the center of the cylindrical shielding conductive pipe Eâ€², and they are exactly or substantially symmetrical in terms of position and configuration with respect to the line joining the centers of the conductive cores A1â€² and A2â€², and the space between the conductive cores A1â€² and A2â€² is controlled by the outer diameter &phgr;C2 of each of the second cylindrical insulator rods C1 and C2.