摘要 |
The invention provides a novel key-board switch unit comprising a printed circuit board having fixed contact points and fixed terminals formed thereon and a covering sheet member having patch-like flexible contacting sheet members bonded on the lower surface thereof and fastened together by means of screw bolts or the like means with a spacer sheet having openings sandwiched therebetween, each of the flexible contacting sheet members being large enough to cover at least one fixed contact point and at least one fixed terminal. Different from conventional ones, the inventive switch unit is assembled together by fastening with screw bolts penetrating the fixed terminals on the printed circuit board so that most reliable electric connection is obtained across the opening in the spacer sheet between the fixed terminal and the flexible contacting sheet member on the covering sheet member which also serves as a movable contact point with the fixed contact point on the printed circuit board.
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