Track ball
US6326951A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 1, 1998 |
| Grant date | Dec 4, 2001 |
| Priority date | — |
| Expiry date | Apr 1, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/03549
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A track ball device includes a body, and a track ball mounted on said body and having an outer hollow sphere and an inner ball fitted in said outer hollow sphere. A method for manufacturing such a track ball includes the steps of a) providing an inner ball, b) providing a global mold, c) positioning the inner ball at a central portion of the global mold, and d) injecting a material into the global mold for encapsulating therein the inner ball to finally result in the track ball. Such a track ball not only avoids the conventional joint seam because the outer sphere is integrally formed, but also greatly reduces the weight because the inner ball is made of a polyurethane (PU) foam material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.