Our cottage has deep-set windows. I’m sure I have seen hinged curtain poles that swing open along the inside of the window embrasure and hope that you can recommend a supplier.
Drapery arm is the correct name for a hinged curtain pole and is one of the prettiest ways to hang curtains at deep-set cottage or dormer windows. Unless the window is very narrow, a pair of arms that swing the curtains together to meet in the centre of the window will be more attractive than hanging the curtains from a single arm.
Another reason to use a pair of arms rather than a single one is that the hinge can only support lightweight curtains and, as they must be self- or contrast-lined (they are seen on one side when open and the other when closed), a single arm may dip under the weight.
You should find what you need from one of these suppliers: Hallis Hudson, (01772) 202202, hallishudson.com, supplies white-coated 20 mm diameter metal drapery arms with gliders, and 20 mm diameter brass drapery arms with brass rings. Copes, 08000 740078, copes.co.uk, can offer 16 mm diameter black, white or silver-coated arms, some with gliders and some with rings, or polished brass arms with rings. Hunter & Hyland, (01372) 378511, hunterandhyland.co.uk, has a made-to-order service for brass drapery arms in a chrome, nickel or antiqued finish. These companies all supply through large and small soft-furnishing retailers, including shops in your area, as well as stores such as John Lewis. Prices for drapery arms range from around £25 up to more than £75.