APPARATUS FOR ALIGNING TWO SHAPED BLANKS SUCH AS RAILS IN CONTACT BUTT WELDING MACHINE Russian patent published in 2002 - IPC

FIELD: welding processes and equipment in different branches of machine engineering, namely manufacture of shaped blanks by contact butt welding. SUBSTANCE: apparatus includes two pickups for detecting distance from common base until aligned surfaces of welded blanks in zone of their butt jointed ends; differential amplifier and error signal shaper connected in series. Inlets of differential amplifier are connected with pickups; outlet of shaper is connected with correcting mechanism. Thyristorized reversing starter has two separate inlets. Error signal shaper includes two comparators whose combined inlets are connected with outlet of differential amplifier and separate inlets - with different-polarity setters of dead zone respectively. Inlets of first and second "AND-NO"-gates and "OR"-gate are connected through diodes with outlets of respective comparators. Inlet of clock pulse generator is connected with outlets of first and second "OR"-gates; outlet of said generator is connected with combined inlets of first and second "AND-NO" gates. Outlets of last are connected with respective separate inlets of thyristorized reversing starter of induction motor of correcting mechanism. EFFECT: possibility for providing preset accuracy degree of alignment of surfaces of welded blanks due to controlling correcting mechanism. 1 dwg