| 摘要 |
559,663. Sliding clasp fasteners. GOLDNER, R. Oct. 12, 1942, No. 14293. Convention date, Sept. 6, 1941. [Class 44] One or both of the elements A, B consist of two or move wires X, Y twisted together to form engaging projections. The interspaces between successive windings of each coil are locally narrower than the maximum thickness t of the windings of the other coil.
|
