Rotatable platform assembly
US4356887A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1980 |
| Grant date | Nov 2, 1982 |
| Priority date | — |
| Expiry date | Dec 29, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66F11/042
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A rotatable platform assembly having upper and lower frames coupled together for rotation of the upper frame relative to the lower frame and about a first and fixed vertical axis. A large diameter ring, having its center at the first vertical axis, is mounted on the lower frame and has a cylindrical vertical outer surface and an annular horizontal track surface. The upper frame has a plurality of rollers in rolling engagement with the track and a chain sprocket mounted thereon and rotatable about a second vertical axis. A standard roller chain is trained around the ring and chain sprocket and the ring is provided with fixed chain-engaging pins and adjustable pad members engageable with the chain to take up chain slack between pins. A manually-operable, lockable and impact-releasable drive means is provided in the upper frame for rotation of the chain sprocket, so that the upper frame rotates about the first vertical axis with the rotating chain sprocket orbiting around such axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.