Ngk Insulators, Inc.

Hiroshi Kashiwagi

Takao Tani

Akio Enomoto

Shinji Tada

Daisaku Goto

Koji Hayakawa

In a method of producing a composite insulator having a core member, end fitting members fixed to both end portions of the core member, and an overcoat member including a sheath portion formed on an outer surface of the core member and shed members, the overcoat member and the end fitting member are connected by curing. Moreover, a clamping operation is performed or a packing member is used for preventing a flow of an overcoat forming material into a seal portion. In this manner, it is possible to improve a seal performance of a connection boundary between the end fitting member and the overcoat member.

Method of manufacturing composite insulator and packing member for use in same

A forming die including of a holder having an upper portion and a lower portion, each portion having a main substrate extending in a first longitudinal direction. A fixing substrate is located on one end of the main substrate and a movable substrate is located on an opposite end of the main substrate and is movable along the main substrate in the first longitudinal direction. A plurality of die forming segments are situated between the movable substrate and the fixing substrate. Tie rods extend along the main substrate outside the periphery of the plurality of die forming segments, and connect the movable substrate and the fixing substrate to one another.

Method of handling a forming die between die forming operations

A disclosed method of repairing a shed portion of a composite insulator having a core portion, a sheath portion arranged on an outer surface of the core portion, and a plurality of shed portions projected from the sheath portion, includes the steps of, (1) cutting out the shed portion having defects from the sheath portion while leaving the sheath portion, and connecting a new shed portion having the same shape as that of the cut out shed portion to the sheath portion at the cut out portion, or (2) cutting out partly the shed portion having defects, and connecting a repairing member to the cut out portion. Therefore, it is possible to perform the shed portion repairing operation without wasting the normal shed portions.

Method for repairing a damaged shed portion of a composite insulator

Forming die and managing method thereof

Method and apparatus for manufacturing a composite insulator including an FRP core rod which is integrally provided with a sheath and a plurality of sheds formed of an electrically insulating polymeric material. The core rod has a longitudinal end portion provided with a seat for a metal fitting, which is integral with the sheath. To manufacture such a composite insulator, the core rod is placed in a mold cavity of a mold assembly, with a seat forming member detachably fitted to the end portion of the core rod and arranged between a pair of mold halves. An inner space is formed between the seat forming member and a core rod, which is in communication with the mold cavity. An electrically insulating polymeric material is introduced into the mold cavity to form the sheath and sheds, while admitting the polymeric material into the space between the seat forming member and the core rod so as to form a seat for the metal fitting, which is essentially free from burrs.

Method for manufacturing composite insulators

A method of producing a composite insulator having a sheath and shed portions molded around a core rod, grasping metal fittings engagingly fitted and fixed at both end portions of the core rod, the sheath covering the core rod between the grasping metal fittings on the whole circumference of the core rod, and a plurality of shed portions extruding radially outwardly from the sheath at plural positions spaced from each other in the longitudinal direction of the core rod, by filling an insulative high molecular material and subsequent vulcanization thereof in the cavity of molding die portions. The methods includes positioning and retaining the core rod at a desired position in the cavity of the molding die portions by means of retaining rings engagingly fitted on the grasping metal fittings and allowing an excess portion of the insulative high molecular material filled in the cavity to flow out to the exterior of the cavity between the grasping metal fittings and the retaining rings.

Method for producing composite insulator

A method of molding a composite insulator having a core member and an overcoat portion arranged on an outer surface of the core member, in which a core member having metal fittings at both ends thereof is set in a metal mold for molding the composite insulator, overcoat portion forming materials are filled in a cavity for molding said overcoat portion formed around the core member, and then the overcoat portion forming materials are cured by heat, is disclosed. The improved method includes a step of making a temperature increase of the overcoat portion forming materials near the metal fittings equal to that of the other portion, when the overcoat portion forming materials are cured by heat, by utilizing an additional heating means.

Method of molding composite insulator and metal molding apparatus used

A molding machine for manufacturing a shaped article which is comprised of a polymeric material and formed in a mold cavity between first and second mold halves of a mold assembly. At least one spring-loaded ejector member is provided in the first mold half and serves to eject the shaped article therefrom. The ejector member is movable toward and away from the second mold half and operates when the two mold halves are being opened. At least one resilient member urges the ejector member toward the second mold half. The resilient member exerts a resilient force to the ejector member, which is smaller than a tightening force of the mold halves. A method for manufacturing a shaped article comprised of a polymeric material includes providing at least one ejector member in the first mold half of the molding machine such that as the mold halves are opened, the ejector member urges the insulator away from the first mold half in which the ejector member is disposed. In one embodiment, the insulator is ejected by use of an ejection member having a distal end that is curved, thereby minimizing damage to the composite insulator.

Method and molding machine for manufacturing shaped articles comprised

A disclosed method of repairing a shed portion of a composite insulator having a core portion, a sheath portion arranged on an outer surface of the core portion, and a plurality of shed portions projected from the sheath portion, includes the steps of, (1) cutting out the shed portion having defects from a portion thereof adjacent to the sheath portion, and connecting a new shed portion having the same shape as that of the cut out shed portion to the sheath portion at the cut out portion, or (2) cutting out partly said shed portion having defects, and connecting a repairing member to said cut out portion. Therefore, it is possible to perform the shed portion repairing operation without wasting the normal shed portions.

Method of repairing shed portion of composite insulator

A method of producing a composite insulator having a sheath and shed portions molded around a core rod, grasping metal fittings engagingly fitted and fixed at both end portions of the core rod, the sheath covering the core rod between the grasping metal fittings on the whole circumference of the core rod, and a plurality of shed portions extruding radially outwardly from the sheath at plural positions spaced from each other in the longitudinal direction of the core rod, by filling an insulative high molecular material and subsequent vulcanization thereof in the cavity of molding die portions. The method includes positioning and retaining the core rod at a desired position in the cavity of the molding die portions by means of retaining rings engagingly fitted on the grasping metal fittings and allowing an excess portion of the insulative high molecular material filled in the cavity to flow out to the exterior of the cavity between the grasping metal fittings and the retaining rings.

Apparatus for manufacturing a composite insulator including an FRP core rod which is integrally provided with a sheath and a plurality of sheds formed of an electrically insulating polymeric material. The core rod has a longitudinal end portion provided with a seat for a metal fitting, which is integral with the sheath. To manufacture such a composite insulator, the core rod is placed in a mold cavity of a mold assembly, with a seat forming member detachably fitted to the end portion of the core rod and arranged between a pair of mold halves. An inner space is formed between a seat forming member and the core rod, which is in communication with the mold cavity. An electrically insulating polymeric material is introduced into the mold cavity to form the sheath and sheds, while admitting the polymeric material into the space between the seat forming member and the core rod so as to form a seat for the metal fitting, which is essentially free from burrs.

Apparatus for manufacturing composite insulators

A composite insulator includes a FRP core rod and a sheath which is formed by integrally molding an insulating polymeric material to cover the core rod over substantially the entire length thereof. The sheath is composed of a plurality of molded portions which are aligned with each other in the axial direction of the core rod. Adjacent molded portions of the sheath are arranged relative to each other so that a gap is left between the opposite ends of the molded portions. The gap is filled by a joint insulating material which is integrally united to the polymeric material of the adjacent molded portions.

Growing community of inventors

Nagoya, Japan

Hiroshi Kashiwagi