GB1312927A - Non-contacting switching device for producing electrical pulses - Google Patents

Abstract

1312927 Oscillating generators KOMBINAT ZENTRONIK VEB 22 May 1970 24806/70 Heading H2A A non-contacting switching device for producing electrical pulses has a permanent magnet 5, Fig. 1, mounted for rotation between the poles of a soft magnetic circuit on which is wound a coil 4, the magnet being rotatable between stops 6, 7 by projections 9, 10 on a key 8. The magnet is poled as shown in Fig. 1, and therefore has two stable positions defined by the stops. The speed of rotation of the magnet may be made largely independent of the speed of movement of the key by using the field from a second permanent magnet mounted either on the key to replace the projections, or on the same axis as magnet 5 and actuated by the projections. The movement of the magnet may be lessened by using appropriately shaped polepieces. The coil output may be used to switch on a transistor, Fig. 4 (not shown), or if it is desired to use the output from both downward and upward key motion the coil is centre-tapped and connected to a pair of transistors in pushpull, Fig. 6 (not shown). Several such devices may be used in a keyboard, to control data processing and electronic storage apparatus.