GB895767A - Method and apparatus for plane separation calibration in balancing machines - Google Patents

Abstract

895,767. Measuring rotor unbalance electrically. GISHOLT MACHINE CO. July 18, 1960 [March 21, 1960], No. 24925/60. Class 40 (1). The unbalance of a rotor is measured in two bearing planes and the signals combined by two sets of potentiometers in proportions determined by the distances between the bearing and balancing planes so that the resultant output signal from each set of potentiometers is indicative of the unbalance at each balancing plane, respectively. As shown (Fig. 1) a rotor 1 produces unbalance signals in pick-ups 6, 7 which are combined in one of two sets of potentiometers 24, 25 as selected by ganged switch 8. The sliders 29, 33 of the left-hand potentiometers 24, 25 are previously adjusted together so that the proportions of the unbalance signals selected by the sliders are exactly equal and oposite for a perfectly balanced rotor 1 with an unbalance mass 34 in the right-hand balancing plane 5. Thus, when an unbalanced rotor 1 is tested, the output signal from the seriesconnected sliders 29, 33 is indicative of the unbalance in the left-hand balancing plane 4 only. This signal is scaled by preset slider 42 of potentiometer 26 to give units of weight to be added, or depth of hole to be drilled, as indicated on a meter 16, after filtering at 12 and amplifying at 13. The unbalance signal may also be fed to a Stroboglow lamp 15 for indicating the angular position of the unbalance relative to a scale 46. Operation of switches 8, 11 enables the magnitude and angular position of the unbalance in the right-hand balancing plane 5 to be indicated by meter 16 and lamp 15, after calibration of the sliders of the right-hand potentiometers 24, 25 with an unbalance mass 37 in the left-hand balancing plane 4 of a perfectly-balanced rotor.