Threaded insert having a small external diameter for screws having a trapezoidal thread
US4906151A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 10, 1989 |
| Grant date | Mar 6, 1990 |
| Priority date | — |
| Expiry date | Mar 10, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B37/125
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A sturdy threaded insert for screws having a trapezoidal thread. To keep the external diameter of this threaded insert small (due to the limited space often available), and to ensure that the female thread produces a perfect seal (if the threaded insert is closed in construction), the threaded insert is constructed as follows: The basic shape of the threaded insert represents a circumscribed quadrilateral, which is a rhombus if the trapezoidal thread is symmetrical and is a parallelogram if the trapezoidal thread is asymmetrical. The superimposed quadrilateral profiles are connected to one another by a web having a minimum wall thickness of about 30% of the useful profile depth of the screw thread, and in any case is at least 0.3 mm. In addition, the threaded flank projections of the annular surfaces are equal on the workpiece side and on the screw side.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.