| 摘要 |
The hinge (1) is spring-loaded by means of a coil spring (17) inside a tube (5) covering the end of the frame side-piece (3) and pressing a projecting end (51) of the tube against a stop on the lens surround portion (7) of the frame. The tube is made e.g. from injection-moulded stainless steel, and is fitted with an anti-friction sleeve (13) in its end adjacent to the hinge, made from bronze, nickel silver or brass. In a variant the end of the tube can have an anti-friction coating deposited e.g. by anodisation or produced by ionic nitration. |
