Process of making a set of distinguishable robertson driver bits
US6490950B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Feb 15, 2001 |
| Grant date | Dec 10, 2002 |
| Priority date | — |
| Expiry date | Feb 15, 2021 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25B13/56
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A set of driver bits for Robertson screw fasteners includes driver bits (10a-d) whose shaft bodies (12a-d) have distinctive markings thereon corresponding to respective sizes of working tips (14a-d) of the driver bits. These distinctive markings are consistent throughout a family of sets. In one embodiment the distinctive marking are different colors, with each different color corresponding to a working-tip size. The colors are applied only to shaft bodies (36a-d) of some of the driver bits by plating the shaft bodies with zinc layers (22) and then dying the outer surfaces of the zinc layers with color dye (24). This coloring is carried out before the shaft bodies are connected to their respective working tips. Once the outer surfaces (20) of the shaft bodies are thusly colored, the respective working tips are swaged to the shaft bodies to thereby form color-coded Robertson driver bits. In another embodiment, the distinctive markings are surface-irregularity rings (32) extending about the elongated shafts, with the least number of rings corresponding to the smallest size working tip and the most number rings corresponding to the largest working tip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.