FIELD: mechanical engineering; hitch mechanism hydraulic systems; testing and diagnosing. SUBSTANCE: hitch mechanism is loaded with continuously increasing force providing incomplete travel of hydraulic cylinder rod, first to pressure at which spool automatic control valve operates, and then to safety valve operating pressure. Indicated parameters are determined by rod travel or by value of force applied to hanger axle. No connection to hydraulic system is required for testing. Test takes from 1 to 2 minutes. EFFECT: facilitated testing, reduced time taken for testing. 1 dwg
