GB535330A - Improvements in and relating to the testing of the setting of vehicle wheels - Google Patents

Abstract

535,330. Alignment gauge for vehicle wheels. BILSTEIN, H. April 5, 1939, No. 10586. Convention date, Sept. 28, 1938. [Class 106 (ii)] Comprises a method and means for testing the setting of vehicle wheels in which a ray of light is directed from a projector on to a mirror and the position of the reflected ray is read on a scale, the projector, mirror and scale being placed in pre-determined positions relatively to each other and to the wheels being tested. A beam 3 is provided at one end with a support 4 and at the other with a trestle 5 arranged on sleeves 6 slidably clamped at 7. The sleeve for the support 4 and another adjustable sleeve carry feelers 8 to engage the wheel rim. The beam engaging the wheel 1 carries a mirror 10 on a slidably adjustable sleeve 9. On the beam engaging wheel 2 is an adjustable sledge 11 carrying a scale 13 provided with an opening 14. Secured to the sledge is a socket 17 adapted to receive a projector 18 containing a lamp 19, a disc 20 with a slit, and a lens 21. The projector 18 is rotatable so that the slit may be horizontal or vertical. A spirit level 23 with crossed levels and telescopic supports enable the devices to be set up horizontally. For "toe-in" the device is set up as in Fig. 1, with the beams parallel to the planes of the wheels. The light coming through the vertical slit is reflected from the mirror 10 on to the scale 25 and the distance of the reflection of the slit from zero gives the required value. For " tilt " of the wheel, a holder as shown in Fig. 5 is used. Two bars 29, 30 which by slots and screws can be adjusted and fixed carry magnetic spools 33 at one end and a bent up part 34 at the other end by which the device may be secured to the wheel rim. A mirror 10<SP>1</SP> is attached to the holder. The mirror .frame allows the mirror to be secured either parallel or perpendicular to the plane of the wheel. The beam carrying the scale 13 and projector is set up at a fixed distance from the wheel by means of a rod pivoted to the sledge or chain &c. The slit is set horizontally and the angle of tilt read off the on scale 26 For " castor " and " spread " the device is use similarly, the wheels being locked and scales 27 used. " Wobble " is measured by rotating the wheel with mirror attached about its axis. The light ray falling on the scale remains fixed if there is no wobble. The amount may be measured by providing adjusting screws for the magnets so that the light ray may be brought to be stationary. Parallelism of the two axles is measured by putting T-pieces on to the ends of the beams and setting the latter to lie in line with the axles.