FIELD: electromechanical engineering; drive motors of pumps for extraction of oil and industrial iodine-bromine waters. SUBSTANCE: compensator has automatic transfer valve mounted in crown and provided with spring-loaded slide- valve piston. Novelty is that in sinking motor-pump unit into well spring- loaded slide-valve piston displaces under effect of hydrostatic pressure thereby providing communication between compensator spaces and, hence, between motor interior and inner space of diaphragm. EFFECT: enhanced reliability, facilitated mounting. 1 dwg
