| 摘要 |
This invention relates to a spring balance, and in particular to a spring balance for use with a sliding sash window. The invention provides a spring balance (20) comprising a top assembly (22; 222) which is secureable to a frame member (10), a bottom assembly (24) which is secureable to a sliding sash (16), a tension spring (26) connected to the top assembly and to the bottom assembly, a torsion spring (30), a spiral rod (32), and a follower bush (34) interconnecting the spiral rod and the torsion spring, the spring balance being adjustable at the top assembly, characterised by a limit mechanism (209, 211) for limiting the range of adjustment. The limit mechanism prevents over-adjustment of the spring balance. |
