초록 ▼

A joint configuration for joining two articles of thermoplastic material by thermal bonding using an electrical heating element, wherein a female fitting having a portion with an enlarged diameter receives the end of an inserted pipe on two raised portions constituting lands on the inner diameter of

A joint configuration for joining two articles of thermoplastic material by thermal bonding using an electrical heating element, wherein a female fitting having a portion with an enlarged diameter receives the end of an inserted pipe on two raised portions constituting lands on the inner diameter of the fitting, and the central annular recess between the two lands receives and positions the electrical heating element which fuses the thermoplastic material. The two lands, each compressed against the outside of the inserted pipe by an external clamp, confine and retain the fused thermoplastic material within the central annular recess to effect an increased internal pressure which promotes the formation of an extensive, continuous, and sound bond between the fitting and the inserted pipe.

대표청구항 ▼

A bonding sleeve assembly for thermally bonding a first thermoplastic article to a second thermoplastic article, comprising: an enlarged generally cylindrical extension formed on one end of the first article having an opening for receiving one end of the second article; an internal annular recess fo

A bonding sleeve assembly for thermally bonding a first thermoplastic article to a second thermoplastic article, comprising: an enlarged generally cylindrical extension formed on one end of the first article having an opening for receiving one end of the second article; an internal annular recess formed within said enlarged extension and spaced axially a short distance from the one end of the first article to define a first internal annular land and between said recess and the one end of the first article; a second internal annular land spaced axially from the first land and separated therefrom by said recess; a spiral welding coil formed from thermoplastic material surrounding a heating element for insertion into said recess, said coil having an outside diameter generally corresponding with the inside diameter of said recess and an inside diameter generally corresponding with the inside diameter of the first land, said coil being manually compressible to a reduced diametric size to fit past the first land and having sufficient elasticity to return substantially to its original diametric size when positioned in said recess, the thermoplastic material being fusible when electrical current is passed through the heating element to bond the first and second articles with respect to each other; and means for compressing said first and second lands against the second article and constraining the expansion of the thermoplastic material within said recess when heated by the heating element, thereby increasing the pressure within said recess.