Patent GB-963492-A (GB)
Title: Positioning,locating and weighing apparatus for aircraft or the like
IPC: G01G19/07
Filed: 1961-05-04
Abstract: 963,492. Weighing apparatus. P. D. BOLTON. May 4, 1961, [May 16, 1960], No. 16167/61. Heading G1W. [Also in Division B7] An apparatus for turning a large object e.g. an aircraft, about a vertical axis, and for weighing it, comprises a turntable 30 including a platform to take the wheels 26, Fig. 1, of the main landing gear of an aircraft 22, 24 and a dolly 152, to take the wheels 28 of the nose landing gear of the aircraft, the dolly running on a track 146 disposed concentrically of the turntable 30, so that at one position of the dolly the aircraft is completely supported on electric weighing devices, e.g. incorporating strain gauges, which carry the turntable 30 and the section of the track 46 on which the dolly 152 is disposed. The turntable is supported in its centre in the inner ring of a thrust bearing 82, which comprises two concentric rings having confronting grooves (not shown) with ball bearings in the grooves. The outer ring of the thrust bearing 82 is bolted to a frame 60 having recesses 62 which rest on five electric weighing devices 56 arranged round a support 52 in a pit which contains the turntable. The weighing devices 56 may be preloaded so that they may work in their most sensitive range by tightening nuts as 74 on fixed bolts 70 passing through the bottom of the frame 60. The turntable is constructed of sectors 110, each sector being a hollow box-like structure of welded steel sheets with side members 121, the top member being paved e.g. with concrete. The top member is strengthened by T-section girders 122 welded to it and these girders project from one side of each sector 110 so as to support the adjacent sector. The sectors 110 together form a circular platform which is secured to the inner ring of the thrust bearing 82 by bolts passing through the plate 102 of each sector 110. The outer edges of the turntable are supported on wheels 139 fixed to the sectors 110, which run on a circular track 140 in the pit which contains the turntable. The turntable 30 is rotated by an electric motor 134 which drives a pinion 128 engaging with teeth (not shown) formed on the inside 126 of the inner ring of the thrust bearing 82. Access to the motor 134 is gained by removal of a central manhole cover 38. The track 140 is formed of a plurality of sections having ends 142, 144, Fig. 6, arranged with gaps therebetween, so that when the wheels 139 are arranged to be above the gaps they leave the track 140 and the whole weight of the turntable, and that part of the aircraft carried by it, is supported on the weighing devices 56 to enable this weight to be determined. The dolly 152 Fig. 1, 7, runs on rails 148, 150 which may be disposed to form a complete circle round the turntable 30 or to form a semi-circle as shown in Fig. 1. The rails 148, 150 are at ground level and stations 156, 158, 160 are provided round the track 146 with rail sections which may be lowered e.g. by hydraulic jacks (not shown) to bring the top of the dolly 152 to ground level to facilitate the movement thereon of the nose landing wheels 28 of the aircraft. After the wheels 28 have been positioned on the dolly at one of the stations 156, 158, 160 it is raised on the rail sections provided at that section and is then free to move along the rails 148, 150. A station 162, Fig. 7, is also provided, and this may be one of the stations 156, 158, 160 in which rail sections, as 170, are supported on four electric weighing devices 58. Thus if the arrangement is such that when the dolly 152 and the nose wheels 28 of the aircraft are fully supported on the rail sections, as 170, the wheels 139 on the turntable 30 are clear of the track 140, i.e. they are between adjacent ends of the sections of. the track 140, then the total weight of the aircraft can be found by use of the electric weighing devices 56, 58, the outputs of which are fed to a computer (not shown). Furthermore the centre of mass of the aircraft in a horizontal plane may be located by calculation from the separate outputs of the weighing devices.