JOAP: HITACHI - Transport Applications - 2020

Merits of Hitachi Pioneering High-Side Pressure Design High Reliability & Comfortable Operation Advantages (1) A simple structure leading to fewer superfluous parts • Damage is abated, improving reliability • Compressor efficiency is improved Low-side pressure design (Thrust Bearing System) There are many sliding components, making for a complex structure. → Damage occurs easily → Gaps form easily, resulting in degradation of compression efficiency The thrust bearing provides imposition of the orbiting and fixed scrolls. Tip-seal is needed to bridge the gap. Fixed Scroll Tip-seal Thrust Bearing Orbiting Scroll 2. 1. Axial force continually adapting → Blending discharge pressure and compressed suction pressure → Leading to optimized performance throughout the operating envelop No tip-seal thanks to the narrower gap between the orbiting and fixed scrolls → Less risk of damage → Oil film seals involute section of scroll set → Reducing compression leakage for improved performance and lower sound Fixed Scroll Orbiting Scroll 2. 1. Back Pressure Port Oil film