Focusing Plate for a Magnetic Actuator
Original Publication Date: 1981-Aug-01
Included in the Prior Art Database: 2005-Feb-12
A resilient magnetic hammer beam is held in retracted spring loaded condition against center pole piece 11 by the magnetic attraction force produced by strip permanent magnets 12 and 13 which are mounted on the top of pole pieces 14 and 15, respectively, of magnetic core 16. Impact blade 17 is attached to beam 10 in alignment with center pole piece 11. Magnetic focusing plate 18 on magnet 12 has a comb-like structure including focusing plate sections 19 separated by air gaps 20. Each of the focusing plate sections 19 has focusing fingers 21 and 22 extending beyond the inner edge of permanent magnet 12 to form U-shaped notch 23 which receives tab section 24 of beam 10. Notch 23 is dimensioned so that a more or less uniform gap 25 exists between the end and side edges of tab section 24.