| 摘要 |
1,184,475. Digitizers. BALL BROS. RESEARCH CORP. 5 June, 1967 [27 June, 1966], No. 25830/67. Heading G4H. An encoder for digitizing for example the position of a drum 14 (Fig. 1), having a pattern of conductive and non-conductive segments arranged in bands 12 includes means e.g. a spiral cam surface 28 and cam follower 30, to move a brush 10 to scan the drum 14 parallel to its axis to give a pulse train output representing the rotation of the drum. The apparatus may be used for measuring the pressure in an oil well by using a Bourdon tube 46 to position shaft 45 or for measuring temperature or liquid level. In the embodiment described a second brush 23 is moved over a plate 24 having alternating conductive and non-conductive segments so that when the first brush is on one of the bands 12 of the drum the second brush is on a conductive segment. |
