Magnetic tape cassettes
US4819890A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1987 |
| Grant date | Apr 11, 1989 |
| Priority date | — |
| Expiry date | Sep 28, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B23/087
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic tape cassette has an improved reel spring, slack limiter and tape guide. The reel spring has a generally rectangular shape with first and second parallel edges extending substantially along its entire length. A flat, central base portion of the spring is bounded by a pair of transition portions which extend at an angle out of the plane of the base. A pair of outer end portions set at a sharper angle to the base complete the spring configuration. A polypropylene slack limiter applies a preloaded tension on the magnetic tape. The polypropylene eliminates the need for laminating a separate bearing material to the slack limiter. The tape guide has a semi-cylindrical, stainless steel insert attached to a plastic mounting core. The core is fastened to the cassette housing. Another form of tape guide has a corrugated surface to minimize contact with the tape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.