GB863029A - Improvements in or relating to arrangements of the kind which includes an electricalposition-encoder for providing electric signals that are representative in digital form of the angular position of a rotatable shaft - Google Patents

Abstract

863,029. Electric selective signalling systems. GENERAL ELECTRIC CO. Ltd. April 2, 1959 [April 2, 1958], No. 11312/58. Class 40 (1). [Also in Group XXIV] A position encoder 20 of the type described in Specification 863,027, which provides electric signals representative of the angular position of its shaft 10 is utilized to indicate the angular position of a shaft 2 coupled thereto by a Geneva mechanism 6, 7 (see Group XXIV), providing a step-by-step movement of shaft 10 relative to shaft 2. As shown, the driving- member 6 of the Geneva mechanism is driven through gears 1, 3 from shaft 2 whilst the driven member 7 is coupled by gears 8, 9 to the shaft 10, the shaft 2 performing sixteen revolutions to one of the shaft 10. Thus each of the 32 digital positions of shaft 10 corresponds to ¢-revolution of shaft 2 and encoder 20 provides signals representative of the position of shaft 2 over sixteen revolutions to a ¢-revolution thereof. The shaft 2 may be provided with a second encoder 19 which gives signals representative of the angular position of the shaft within each ¢-revolution so that the combination of the signals from both encoders gives an indication of the position of shaft 2 to <SP>1</SP>/ 16 of a revolution in sixteen complete revolutions.