Patent GB-457622-A (GB)
Title: Improvements in automobile wheel aligning apparatus
IPC: G01B5/255
Filed: 1935-08-06
Abstract: 457,622. Gauging alignment of vehicle wheels. FOOD MACHINERY CORPORATION, 333, West Julian Street, San JosÚ, California, U.S.A. Aug. 6, 1935, No. 22216. Convention date, Sept. 17, 1934. [Class 106 (ii)] An aligning gauge for automobile front wheels comprises a unitary device for checking " camber," " caster," " king-pin inclination," toe-in, and toe-out giving direct readings, said device including an indicator arm with means associated therewith for holding the arm in any adjusted position relative to the reading'scales whether the arm is horizontal or vertical. The vehicle is run up over runways until the front wheels rest on turntables 6, stops 51 preventing overrunning. The turntables are supported on base members 5 provided with guideways on which slide pillars 4 carrying the testing units. The turntable, Fig. 9, comprises a plate 6 resting on ball bearings in a retainer plate 44, the balls 43 resting on a plate 47. The plates 6, 44 are held normally central by flat spiral springs 45, the inner ends of which engage the hub 49 and the outer ends the plates. Spring friction plugs 46 exert a damping action on the free movement of the table. Each unit, Figs. 1, 6, comprises a bar 52 rotatably mounted and having fastened thereto a quadrant 25. The standard 4 is moved to and from the wheel by a lever 55 and is held frictionally in adjusted position by a spring 57. The bar 9 is held frictionally in its guide by spring buttons. Caster. This is the amount the king-pin is inclined towards the rear and is corrected first. The front wheel is turned to an angle of 25‹ by aligning it with the raised line 8 on the base. The contact bar 9 is placed vertical with the shoes 10 touching the bulges of the tyre. Now the screw 12 is loosened and the small caster scale 10a adjusted so that the caster indicating line 11 points to zero when the screw is again tightened. The device is now slid back, the wheel turned to align with the 25‹ mark 13 and the shoes again moved to contact with the tyre. The indication given by the mark 11 now gives the required angle. The same operation is performed for the other wheel and the " caster " corrected by placing tapered shims between the underside of the spring and the supporting saddle. Camber. This is the amount the wheels are inclined outwards at the top. The wheels are set straight ahead and the bar 9, Fig. 6, is set vertically, a special shoe 18 being placed so that the inclined face 19 engages the bulge of the tyre, the lower end resting on the turntable. A special shoe for engagement with the wheel felloe may be used. The degree of camber is now read on the scale 22. King-pin inclination. The wheels are set to the 25‹ mark on the scale 10b and locked by the brakes. The flat pointed markers 24 are adjusted along the bar 9 until they touch the sides of the tyre at the highest points, the stop pin 28 being removed to allow bar 9 to swing. The instrument is drawn back, the pointers chalked, and replaced to mark the contact points. Now the unit is withdrawn and the wheel moved to the opposite 25‹ angle. The king-pin inclination will change the vertical height of the chalk marks so that when the unit is again moved up to the wheel it will be necessary to swing the bar 9 and quadrant 25 to bring the ends of the pointers 11 up to but below the marks. They are now elevated by the screws 26, the bar 9 being swung until alignment is obtained. The king-pin inclination is now read off on scale 27. A fine adjustment is provided for the last swinging of bar 9. Toe-in. This is the amount the distance between the wheels at the back is less than the distance apart at the front. The unit is placed against either wheel, and the latter moved until the mark 37 on the arm 14 is at zero on scale 38. This wheel will now point straight ahead. Now, when the apparatus at the other side of the car is adjusted to the wheel, the toe-in will be indicated. Toe-out. With the bar 9 in a horizontal position, the unit is set right up to the near side wheel which is turned until the mark 37 indicates 20‹. The unit for the other wheel is now set to the wheel when, if toe-out is correct for the wheel base as obtained from data prepared, it should also show a reading of 23‹. As an alternative to the marks 8, 13, set-screw stops may be provided to limit the swinging of the wheel to the desired angle of 25‹. The pointer 14 is held frictionally.