GB996351A - Improvements in programme preselectors - Google Patents

Abstract

996,351. Switches held set and freed mechanically; retractive switches. W. HOLZER. April 24, 1962 [May 8, 1961], No. 15630/62. Heading H2B. A programme selector switch for washing machines comprises a slot-like socket 3 for a removable actuating plate 2, the slot 3 having openings at its lower end to allow water to drain away, while the contacts are arranged in a space separated from slot 3 and are actuated by means of angular levers 8 or 9. A plurality of fixed contacts 22, each has a cooperating moving contact 21 carried on limb 20 of an angle-piece 19, the other limb of which extends in the form of a serpentine spring 24 and has a connecting lug 25 formed at its end. An adjoining lug 27 has a bifurcated end portion 28 which is spread to anchor the spring in the casing. The upper wall 4 of socket 3 is spaced from the part 6 to allow angular levers 8 or 9 to pivot about the rounded end 10 of wall 4 when engaged by the plate 2. Levers 8 (Fig. 1) have tabs 12 which lie in grooves 13 in the plate 2 or, in the absence of a groove are lifted to cause contacts 21, 22 to open when the plate 2 is in position in socket 3. Alternatively, the contacts 21, 22 may be normally retracted open by virtue of springs 35 urging arms 9 as in Fig. 2, and pressure on plate 2 is then needed to allow the contacts to close. This may be utilized for temporary closure of a " start " contact. Alternatively, since slot 3 is preferably nearly vertical, gravity may cause plate 2 to actuate a plurality of contacts arranged as in Fig. 2. In all embodiments the limb 17 produces a longitudinal component of movement in springs 24 and hence a self-cleaning action of contacts 21, 22.