Patent GB-1381540-A (GB)
Title: Longitudinal positioning stop for fixed station automobile vehicle  test beds
IPC: G01M17/007
Filed: 1972-09-07
Abstract: 1381540 Testing vehicles SOC ANON FRANCAISE DU FERODO 7 Sept 1972 [8 Sept 1971] 41596/72 Heading G1W A vehicle test apparatus includes a vehicle positioning device which allows the vehicle five degrees of freedom of movement i.e. vertical and lateral translation, rotation about a vertical axis, and rotation about two horizontal axes. The device, Fig.2, comprises a frame 12, a carriage 10 movable laterally along the frame, a column 13 movable vertically in the carriage, a bracket 14 rotatable about the column, a first rotating box 16 rotating about a first horizontal axis passing through the centre of rotation CR by virtue of being mounted to bracket 14 by rollers 18 and arcuate slots 17, and a second rotating box rotating about a second axis passing through CR by virtue of being mounted on the first box by rollers 21 and arcuate slots 20, the first and second axes being mutually perpendicular. In the more detailed description with respect to Figs. 4, 5 and 6, the frame 12 comprises a vertical beam 31 having two horizontal flanges 32, 33, the carriage 10 being mounted on the frame 12 by rollers 35 engaging slots 34, Figs. 5, 6. The carriage 10 includes two vertical slide guides 36, Fig.4, which co-operate with vertical ribs 37 on the column 13 for guiding the column for vertical movement. The top of the column carries a cantilever block 40, Fig.6, to which the bracket 14 is journalled by bearings 45 the bracket 14 comprising a flange 42 and two lateral extensions 46, Fig. 4. The first rotating box 16 takes the form of a frame disposed about bracket 14. The side members 50 of box 16 each include arcuate slots 51 which co-operate with rollers 52 mounted on the bracket 14. Guide rollers 56 mounted on the bracket 14 engage the surfaces 54 of member 50, Figs 4 and 5. The second rotating box 19 is in the form of a frame surrounding box 16. The side members 59 of box 19 carry rollers 16 engaging circular slots 63 in box 16. Guide rollers 61 mounted on members 59 engage surfaces 62 on box 16, Figs. 4 and 6. A vehicle support platform 15, Fig.5, is mounted on box 19, and comprises two flaps 65 rotatably connected to the box 19 for supporting the vehicle at a height such that its centre of gravity is at the centre of rotation, CR. Each flap 65 is connected to box 19 by a linkage including a link 68 which is pivoted to a slide 73 and connected to a nut 70 mounted on a threaded bar 71. Rotation of bar 71 thus adjusts the effective length of the linkage and the height of the flap. Each flap also carries a roller 80. To restrain rotation of bracket 14 relative to column 13, a torsion bar 82 is connected to the lower end of column 13. The upper end of torsion bar 82 is connected to a member 83 carrying a roller 85 engaging in a slot 86 of the flange 42 of the bracket 14, the roller 85 being adjustable along the member 83. A chamber 90, Fig.5, is provided in torsion bar 82, and a piston 92 slides in this chamber. The piston 92 is supported at its lower end by a ball thrust bearing 93 and force pick-up 94, and the pressure in chamber 90 is controlled by the pick-up 94 and an accelerometer (not shown) via a servosystem to compensate for the inertia of moving parts in a vertical direction. The carriage 10 is driven by a threaded bar 96 and a nut 97, the nut being provided with a force pick-up to measure the driving force applied. The rotation of bar 96 is controlled by the force pickup via a servosystem to compensate for the inertia of the moving parts. The screw 96 may also apply a force to simulate a cross-wind.