Self-aligning lunette

One general view drawing. Description of the design and principle of operation of the device being developed: Lunet is used as an additional support to avoid deflection of shafts when machining them on metal cutting machines. The developed lunet is used in the turning of the axis on the model 16K20 machine. Lunette comprises two carriages 1 movably mounted on guides 2 of base 3 arranged on machine bed. Each of carriages comprises two rollers 5 and holding roller 6 under it. Rollers 5 are loosely rolled along guides 2 of base 3, roller 6 being support for shaft barrel. Rollers 5 and rollers 6 are installed on self-aligning bearings, for example spherical ones. Both carriages are connected by tightening device made in form of two screws 7 with different direction of thread and double mother nut 8 which is simultaneously worm wheel engaged with worm 9. Rollers 6 mounted on carriages by means of worm 9, nut 8 and screws 7 are brought into contact with shaft barrel. A further increase in the pulling force allows the rollers 6, by means of the rollers 5 rolling on the base 3, to self-set relative to the shaft, regardless of the possible errors of the guides 2 and 1 of the lunette mechanism itself, and to bring the shaft axis line to a strictly horizontal position. Thereafter, the lunette carriages are fixed to the guides 2 of the base 3 by means of the clamps 10.