Apparatus for balancing a rotatable body which must have its centre of gravity on a specified axis

摘要

567,321. Testing balance of propellers. MILNER, H. L., EYLES, R. E., and HAYES, J. G. June 2, -1943, No. 8859. [Class 106 (ii)] [Also in Groups XXV and XXXIII] In a device for testing the statical balance of an aeroplane plane propeller or other body, in which a mandrel 4 is secured to the propeller in line with its rotary axis and suspended from a freely pendulous member 19, a shaft 9 is adjustable lengthwise of the mandrel and forms the support for the outer race 16 of a spherical ball bearing, the inner race 20 of which is mounted on the member 19. Lack of balance of propeller results in lack of alignment of members 4, 19 which 'is indicated by a disc 30 moving outside a circle 29. When the device is not in use, a spring 23 moves the member 19 and a cup-shaped member 25 carries it so that it abuts against the balls or the ball cage and aligns them in relation to the race-tracks.