| 摘要 |
1,158,070. Selective printing. ANELEX CORP. 24 Oct., 1967 [17 March, 1967], No. 48335/67. Heading B6F. Hammer impression arrangements.-The actuating arm 34 for a hammer 18 is pivoted at 36 and is actuated between the pivot and where the hammer 18 is engaged and preferably at its intrinsic centre of percussion (a distance L from the pivot). As shown the actuating force is derived from an electromagnet 42 with a main polepiece 44 which forms a stop for the armature 34 while the hammer 18 continues by momentum to effect impression. A secondary polepiece 45 and an extension 46 is also provided on the electromagnet. Multi-hammer assemblies may use a single core 42 with individual polepieces 44, 45 and actuating arms. Anti-rebound.-The extension 46 carries a bolt 56 around which is a spring 58 for returning the armature against anti-rebound non-planar polyvinyl chloride damping washers. Machines.-The hammer mechanism can be applied to continuously rotating type-drum, endless type-band or reciprocating shuttle machines. |
