Rotary pump with higher discharge pressure and brake apparatus having same

摘要

In the rotary pump, a high pressure outer circumference chamber, which is formed around an outer circumference of an outer rotor and communicates with a discharge port, presses radially inward first defined parts among the outer circumference of the outer rotor that are positioned radially outside second defined parts adjacent to teeth gap portions whose volume are largest and smallest among teeth gap portions communicating with an intake port. Teeth top clearance between the outer and inner rotors at the second defined part is reduced due to pressure difference between the discharge pressure applied to the first defined parts and the intake pressure applied to the second defined parts.