Hauling cord
OwnerMinoru Takahashiinventor
Life of this patent
Estimating the term…
Abstract
A hauling cord (L) for pulling an electric power line or the like cable into a conduit has an elongate linear body (1) that is typically a monofilament of a thermoplastic resin. The cord is of a regular or irregular cross section with one or more helical ridges (2) that extend around, along and integral with the linear body between opposite ends of the linear body. The helical ridges are formed by drawing and twisting a raw material of the linear body, and may have either of or both the opposite ends made thinner and/or twisted stronger than the remaining portion so that the pitch between the adjacent ridges is reduced. The cross section renders the cord lighter in weight and more slender, and nevertheless its compression strength and tensile strength are improved.
Claims24
A hauling cord comprising an elongate linear body made of a thermoplastic resin and having a transverse cross section of a polygonal contour, said cord having a plurality of helical ridges that are included in the polygonal contour and each extend around, along and integral with the linear body, wherein the helical ridges are formed by drawing and twisting a raw material of the linear body, and a guide piece affixed to one end of said hauling cord, said guide piece having a hole therethrough.
A hauling cord having opposite ends and an intermediate region comprising an elongate linear body made of a thermoplastic resin having a transverse cross section of a polygonal contour, and a guide piece affixed to one end of said hauling cord, said guide piece having a hole therethrough, said cord having a plurality of helical ridges that are included in the polygonal contour and each extend around, along and integral with the linear body, wherein the helical ridges are formed by drawing and twisting a raw material of the linear body, and wherein a pitch of the adjacent helical ridges in a longitudinal direction for at least one of said opposite ends of the cord is different from that for said intermediate region.
A hauling cord having opposite ends and an intermediate region comprising an elongate linear body made of thermoplastic resin and having a transverse cross section of a polygonal contour, and a guide piece affixed to one end of said hauling cord, said guide piece having a hole therethrough, said cord having a plurality of helical ridges that are included in the polygonal contour and each extend around, along and integral with the linear body, wherein the helical ridges are formed by drawing and twisting a raw material of the linear body, and wherein at least one of said opposite ends of the cord is thinner than said intermediate region.
A hauling cord having opposite ends and an intermediate region comprising as an elongate linear body a monofilament made of a polyester resin and having a transverse cross section substantially of a regular triangle, and a guide piece affixed to one end of said hauling cord, said guide piece having a hole therethrough, said cord having three helical ridges each extending around, along and integral with the linear body, wherein the helical ridges are formed by drawing and twisting a raw material of the linear body, and wherein a pitch of the adjacent helical ridges in a longitudinal direction for at least one of said opposite ends of the cord is smaller than that for said intermediate region, with the at least one opposite end of the cord being thinner than said intermediate region.
A hauling cord comprising an elongate linear body made of a thermoplastic resin and having a transverse cross section of an irregular contour, and a guide piece affixed to one end of said hauling cord, said guide piece having a hole therethrough, said cord having at least one helical ridge extending around, along and integral with the linear body, wherein the helical ridge is formed by drawing and twisting a raw material of the linear body.
A method of cable installation through a conduit comprising the steps of:
- providing a hauling cord having an elongate linear body made of a thermoplastic resin and having a transverse cross section of a polygonal contour, said cord having a plurality of helical ridges that are included in the polygonal contour with each said ridge extending around, along and integral with said linear body;
- passing said hauling cord under compression through the conduit with an end of the hauling cord leading through the conduit;
- attaching the cable to the end;
- and
- drawing the hauling cord back through the conduit to draw the cable through the conduit.
A method of cable installation through a conduit comprising the steps of:
- providing a hauling cord having an elongate linear body with opposite ends and an intermediate region, made of a thermoplastic resin having a transverse cross section of a polygonal contour, said cord having a plurality of helical ridges that are included in the polygonal contour with each said ridge extending around, along and integral with said linear body, said helical ridges formed by drawing and twisting a raw material of the linear body, with a pitch of adjacent helical ridges in a longitudinal direction for at least one of said opposite ends of the cord being different from that for said intermediate region;
- passing said hauling cord under compression through the conduit with an end of the hauling cord leading through the conduit;
- attaching the cable to the end;
- and
- drawing the hauling cord back through the conduit to draw the cable through the conduit.
A method of cable installation through a conduit comprising the steps of:
- providing a hauling cord having an elongate linear body with opposite ends and an intermediate region, made of a thermoplastic resin and having a transverse cross section of a polygonal contour, said cord having a plurality of helical ridges that are included in the polygonal contour with each said ridge extending around, along and integral with said linear body, said helical ridges formed by drawing and twisting a raw material of said linear body, with at least one of said opposite ends of said cord being thinner than said intermediate region;
- passing said hauling cord under compression through the conduit with an end of the hauling cord leading through the conduit;
- attaching the cable to the end;
- and
- drawing the hauling cord back through the conduit to draw the cable through the conduit.
A method of cable installation through a conduit comprising the steps of:
- providing a hauling cord having an elongate linear body with opposite ends and an intermediate region, made of a monofilament polyester resin and having a transverse cross section substantially of a regular triangle, said cord having three helical ridges each extending around, along and integral with said linear body, wherein said helical ridges are formed by drawing and twisting a raw material of said linear body, with a pitch of adjacent helical ridges in a longitudinal direction for at least one of said opposite ends of said cord being smaller than that for said intermediate region, with the at least one opposite end of said cord being thinner than said intermediate region;
- passing said hauling cord under compression through the conduit with an end of the hauling cord leading through the conduit;
- attaching the cable to the end;
- and
- drawing the hauling cord back through the conduit to draw the cable through the conduit.
A method of cable installation through a conduit comprising the steps of:
- providing a hauling cord having an elongate linear body made of a thermoplastic resin and having a transverse cross section of an irregular contour, said cord having at least one helical ridge extending around, along and integral with said linear body, with said helical ridge formed by drawing and twisting a raw material of said linear body;
- passing said hauling cord under compression through the conduit with an end of the hauling cord leading through the conduit;
- attaching the cable to the end;
- and
- drawing the hauling cord back through the conduit to draw the cable through the conduit.
Dependencies are inferred from the claim text.