| 摘要 |
1,272,721. Gravity switches; momentarycontact switches. HONEYWELL G.m.b.H. 8 April, 1970 [12 April, 1969], No. 16657/70. Heading H1N. An electric switch comprises at least two annular tracks extending around an axis 29, containing electrically conductive balls or rollers 7, 8 and including fixed contacts 18, 21, 24 and 19, 25, 26, the tracks being such that if axis 29 is horizontal, on rotation of the switch and consequently the tracks around axis 29, balls or rollers 7, 8 run around the tracks in discrete steps making or breaking contact at each step. The two tracks are formed in a common insulating member 2, the first track being octagonal, see Fig. 2, with convex sides 13 containing at their centres fixed contacts 18 and having corners 15, the second track being octagonal and spaced axially and circumferentially from the first track and having convex sides 14 containing at their centres fixed contacts 19 and having corners 16. Fixed contacts 18 all form part of a ring 3, fixed contacts 19 all form part of a ring 4, rings 3 and 4 being connected together and also through insulated conductor 12 to terminal 10. Fixed contacts 24, 25, 26 are formed by flanges on a conductive member 5 which has an integral pin 23 fitting in a blind bore 22 in outer conductive casing 1, a surface of which forms fixed contact 21 and which has a terminal 9 soldered into it. When the switch is rotated about axis 29, ball 7 rolls from one corner 15 to the adjacent corner 15 and as it passes over contact 18 it momentarily makes a circuit from terminal 9 through casing 1, surface 21, ball 7, contact 18, ring 3, conductor 12 to terminal 10. If the switch is still further rotated, ball 8 rolls from one corner 16 to an adjacent corner 16, momentarily making contact between terminals 9 and 10 when it passes over contact 19. Alternatively, the fixed contacts 18, 19 are located at the corners 15, 16 so that the balls break contact as they roll from one corner to the next. The balls roll alternately as the switch is rotated. In a second embodiment, Fig. 3 (not shown), instead of fixed contact 21 being a surface or casing 1 it is formed by another flange on member 5, and the two tracks have the form of a decagon and are circumferentially offset by 18 degrees. In both embodiments, fixed contacts 18, 19 may be formed by printed circuits, and the interior of casing 1 may be filled with a protective gas. An alternative is to have a sawtooth shaped track, similar to an annular gear-wheel carrying the gear on its inner surface. |
