摘要 |
To adjust the tension in a sash window spring balance, a first component 40 is mounted on the sash, and a second component 50,52 is mounted on the bottom end of the spring balance spiral rod 34. The first and second components have mating faces with ratchet teeth 62 arranged around an annulus centred around the spiral rod, so that when the rod is in tension pulling the first and second components against one another, the components can only rotate in one direction, and when they do rotate, there is a click produced each time the ratchet teeth ride over one another. A socket 66 in the base of the second component allows for a tool 64 to be inserted to rotate the component. |