Window balance spring cover friction system
US4837976A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1988 |
| Grant date | Jun 13, 1989 |
| Priority date | — |
| Expiry date | Mar 21, 2008 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE05Y2900/148
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An extruded resin spring cover (12) extending for the full length of a resin jamb liner (10) and divided into vertical halves (14) by a longitudinal slit (15) is involved in a friction system that prevents hop or drop of a sash (13) counterbalanced between jamb liners (10). A counterbalance spring system is arranged within spring cover (12) and connected to a platform (20) that has a narrow width neck (24 or 44) extending through slit (15). A sash support portion (25, 37, or 57) of the platform is pivotally mounted outside the spring cover, and a connector portion (30, 35, or 40) of the platform is connected to the counterbalance spring system within the spring cover. Neck (24 or 44) extending through slit (15) affords the pivotal interconnection between the sash support portion and the connection portion and also contributes a fixed friction load involved in spreading the spring cover halves apart at the slit, in the region of the neck. The rest of the friction load is provided by a friction shoulder (26 or 46) on the connector portion engaging the inside of the spring cover and a friction surface (27, 38, or 58 ) on the sash support portion engaging the outside of the spring cove…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.