GB171986A - Improvements in and connected with apparatus for testing the position of the center of gravity of rapidly rotating parts of machinery - Google Patents

Abstract

171,986. Krupp Akt.-Ges., F. Nov. 22, 1920, [Convention date]. Void [Published under Sect. 91 of the Act]. Testing balance of rotary apparatus. -Comprises a particular construction of that type of apparatus in which the body to be tested is received on a carrier resting on two coaxial knifeedge bearings. The carrier B is of inverted U-shape provided with knifeedges b<2>, b<3> resting upon V-blocks a<2>, a<3> on a frame A, the base A of which has two spirit-levels at right-angles to each other to ensure that the base is horizontal. The limbs b<4>, b<6> of the carrier carry extensions b<5>, b<7> forming journals for a sliding weight C and a stepped sleeve E which latter receives the body D to be balanced. The journals b<5>, b<7> are coaxial, the bars being parallel to and slightly below the axis of the knife-edges. The frame A is fitted with rectangular yokes a<4>, a<5> which limit the angular movement of the carrier, and a scale is carried by an arm a<6> attached to the yoke a<5>, a pointer b<8> on the carrier working over the scale. The pointer b<8> carries a small pointer b<9> and the carrier has two lateral extensions b<10>, b<11> carrying an adjustable scale pan F and an adjustable weight b<12> respectively. A pointer a<8> is supported by the base A at approximately the line of the knife-edges. Normally, with the base A<1> horizontal, and the pointer b<8> at zero, the pointer b<8>, the pointer b<9> and the axes of the knife-edges and journals lie in the same vertical plane. To use the apparatus, the body D is placed a friction fit on the sleeve E and the weight C so that the pressures in the knife-edges are approximately equal. The body D is then turned relatively to the journal b<7> until the pointer b<8> reads zero. A mark is then placed under the pointer b<9>. The carrier is held and the body D turned until the mark lies opposite the pointer a<8>. The scale-pin F is then adjusted so that its medial plane touches the periphery of the body D at the mark, and the weight b<12> is moved over its scale to balance. Weights are then placed in the scale pan until the pointer b<8> reads zero. This represents the. mass to be added at the marked point to balance the unbalanced force acting on the body D.