Telescopic positioning mechanism for chair backrest
US6299253A · kind A · utility
Inventor
Key dates
| Filing date | Aug 18, 2000 |
| Grant date | Oct 9, 2001 |
| Priority date | — |
| Expiry date | Aug 18, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA47C7/402
- WIPO fieldFurniture, games
- WIPO sectorOther fields
Abstract
A telescopic positioning mechanism for chair backrest comprises a channel on backrest including a notched member, a top ramp, a bottom ramp, and two side grooves, a guide on the chair support including two side tongues slidably engaging with grooves and an anchored torsion spring, and a latch member biased by torsion spring to engage with one notch in a locked position. Pull backrest up in adjusting the height of channel with respect to guide. In turn, the locked latch member is pushed rightward to clear from the notch. Latch member is biased leftward to move into engagement with the next adjacent notch by virtue of torsion spring. In a highest position, latch member moves along bottom ramp to a free position. Then pushes down backrest to cause it to reach its lowest position such that latch member moves along top ramp to a free position. Backrest is capable of being locked by notched member in one of a plurality of vertical positions relative to the seat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.