Electric welding muff
US4117311A · kind A · utility
42Cited by
6References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1977 |
| Grant date | Sep 26, 1978 |
| Priority date | — |
| Expiry date | Mar 14, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C66/949
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A thermoplastic synthetic resin sleeve to be slipped over the end of a tubular member to be joined to another such member has a winding of resistance heating wire adjacent the inner surface of the sleeve. Connectors at the ends of the wire are provided to connect the wire to a source of electrified power. Small diameter wire is chosen, the resistance thereof being selected as an inverse function of sleeve diameter, so that an unregulated source of power can be used. A visual indication is provided to indicate when a good weld joint has been made.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.