Patent EP0303909A2 successfully refreshed from Google Patents.
EP0303909A2
Expired / Lapsed
EP
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Method of manufacturing an electrofusion coupler
Assignee: Glynwed Tubes and Fittings Ltd
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Filing: 1988-08-04
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Granted: —
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Expires: 2008-08-04
Abstract
Abstract A method is disclosed for the manufacture of an electrofusion coupler, for connecting adjoining lengths of thermoplastics pipes, and which coupler takes the form of a sleeve of thermoplastics material, to receive adjoining ends of adjoining pipes, the sleeve having an electrical resistance heater embedded therein and extended around the sleeve. In the method, a plastics preform (10) is wound with a resistance heating wire (12), whilst heating the wire, to melt the surface of the preform, and/or applying molten plastics thereto and possibly running a pressing roller (16) over the preform surface to smooth over the molten plastics, in order to ensure that the heating wire (12) is fully embedded in the preform (10). The preform (10) is subsequently placed in an injection mould and an outer encapsulating jacket is injection moulded around the preform.
Inventors
- 👤 Malcolm Raymond Barfield
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 20:15
CPC Classifications
B; B29; B29D; B29D23/00; B29D23/001; B29D23/003; B29D23/005; B29C; B29C70/00; B29C70/68; B29C70/82; F; F16; F16L; F16L47/00; F16L47/02; F16L47/03; B29L; B29L2031/00; B29L2031/24
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
56 words
A method of forming an electrofusion coupler, as herein defined, comprising forming a preform of thermoplastics material, applying thereto an electrical resistance heating wire and ensuring that the heating wire is fully embedded in the preform before placing the preform in an injection mould and moulding, over the preform, in thermoplastics material, an outer encapsulating jacket.
Claim 2
Independent Claim
56 words
A method of forming an electrofusion coupler, as herein defined, comprising forming a preform of thermoplastics material, applying thereto an electrical resistance heating wire and ensuring that the heating wire is fully embedded in the preform before placing the preform in an injection mould and moulding, over the preform, in thermoplastics material, an outer encapsulating jacket.
Claim 3
Independent Claim
55 words
A method of forming an electrofusion coupler comprising forming a tubular preform of thermoplastics material, winding thereon an electrical resistance heating wire and ensuring that the heating wire is fully embedded in the preform before placing the wound preform in an injection mould and moulding, around the preform, in thermoplastics material, an outer encapsulating jacket.
Claim 4
Independent Claim
55 words
A method of forming an electrofusion coupler comprising forming a tubular preform of thermoplastics material, winding thereon an electrical resistance heating wire and ensuring that the heating wire is fully embedded in the preform before placing the wound preform in an injection mould and moulding, around the preform, in thermoplastics material, an outer encapsulating jacket.
Claim 5
Dependent Claim
64 words
A method according to claim 2 wherein the wire is wound onto the preform under tension and in a heated condition so as to melt the surface of the preform locally in the region of the wound on wire, and wherein, whilst the plastics material is still molten locally, the molten plastics is spread over the partially embedded wire to cover the same completely.
Claim 6
Dependent Claim
34 words
A method according to claim 2 wherein further molten plastics material is applied from an external source over the wound-on wire, to cover the same completely in a layer fused integrally with the pre-form.
Claim 7
Independent Claim
71 words
A method of forming an electrofusion coupler, as herein defined, comprising applying a heating wire to the surface of a support member and simultaneously or subsequently applying molten thermoplastics material to the support member to cover the applied wire, whereby the thermoplastics material will solidify on the support member, and subsequently stripping off from the support member a product formed by said thermoplastics material and having said heating wire embedded therein.
Claim 8
Independent Claim
71 words
A method of forming an electrofusion coupler, as herein defined, comprising applying a heating wire to the surface of a support member and simultaneously or subsequently applying molten thermoplastics material to the support member to cover the applied wire, whereby the thermoplastics material will solidify on the support member, and subsequently stripping off from the support member a product formed by said thermoplastics material and having said heating wire embedded therein.
Claim 9
Dependent Claim
32 words
A method according to claim 5 including the further step, after the stripping off of said product from said support member, of moulding over said product an outer layer of thermoplastics material.
Claim 10
Independent Claim
73 words
A method of forming an electrofusion coupler comprising winding a heating wire around a mandrel and simultaneously or subsequently applying molten thermoplastics material to the mandrel to cover the wound-on wire, whereby the thermoplastics material will solidify on the mandrel, subsequently stripping off from the mandrel a tubular sleeve formed by said thermoplastics material and having said heating wire embedded therein, and subsequently moulding, around said sleeve, an encapsulating jacket of thermoplastics material.
Claim 11
Independent Claim
73 words
A method of forming an electrofusion coupler comprising winding a heating wire around a mandrel and simultaneously or subsequently applying molten thermoplastics material to the mandrel to cover the wound-on wire, whereby the thermoplastics material will solidify on the mandrel, subsequently stripping off from the mandrel a tubular sleeve formed by said thermoplastics material and having said heating wire embedded therein, and subsequently moulding, around said sleeve, an encapsulating jacket of thermoplastics material.
References Cited (Backward Citations)
No citation records indexed.
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