| 摘要 |
686,730. Snap action retractive switches. MINNEAPOLIS-HONEYWELL REGULATOR CO. Feb. 13, 1951 [April 17, 1950], No. 3531/51. Class 38 (v) [Also in Group XXXII] In a snap-action mechanism having a resilient elongated tension member mounted in cantilver fashion and held in tension by a compression member, the tension member has its cross-sectional area reduced over a region close to its mounting so as to increase its flexibility. In the arrangement shown, a unitary blade spring has outer bowed compression members 16 pivotally supported in grooves at the ends of legs 23 of a U-shaped fixed plate 24, and a central elongated tension member 17 with its fixed end secured in a recess 42 in the plate 24 by a screw (not shown). A hole 55 is provided in the member 17 to reduce its cross-sectional area and so increase its flexibility. This increase in flexibility is stated to increase the working life of the mechanism. As applied to a snap-action switch, Fig. 1 (not shown), the spring blade is provided with a contact 41 which cooperates with fixed contacts (not shown) and a push button is arranged to engage the tension member 17 at a point between the mounting and the axis of the pivotal supports of the compression members 16. |
