Fastener unit for clamping plastic workpieces
US4238165A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 25, 1979 |
| Grant date | Dec 9, 1980 |
| Priority date | — |
| Expiry date | Jan 25, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T403/75
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A fastener unit for clamping plastic material having a first predetermined thickness to a relatively thin sheet metal support having a second predetermined thickness. The fastener unit includes a spacer collar having a length substantially equal to the first predetermined thickness, the plastic having a hole to receive the collar. The collar surrounds the upper portion of a threaded shank and the end abuts the sheet metal. The spacer collar has an internal diameter which forms a gap with the threads of a size approximately equal to the second predetermined thickness. As the fastener is threadingly advanced into the sheet metal, the end of the collar serves as a fulcrum about which the threads bend the material which forms the edge of the hole into the gap increasing the stripping torque of the fastener unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.