THERMAL EXPANSION CHAMBER FOR AIRTIGHT CONTAINER, HYDRAULIC PUMP INCLUDING THE SAME, AND METHOD OF USING THE SAME

摘要

PROBLEM TO BE SOLVED: To prevent an airtight pump housing prevented from being subjected to excessive stress by a heated and expanded hydraulic fluid. SOLUTION: The hydraulic pump has a rotor and a hollow housing with a main chamber. The rotor is rotatably mounted in the main chamber. A small sub-chamber is separated from the main chamber such that the small sub-chamber retains a gas therein when the main chamber is filled with a liquid. There is also provided a method for accommodating changes in volume of the hydraulic fluid in the main chamber of the hydraulic pump. The method comprises providing the small sub-chamber separated from the main chamber and retaining the gas in the small sub-chamber when the main chamber is filled with the liquid, whereby expansion or contraction of the gas accommodates changes in volume of the liquid in the housing. COPYRIGHT: (C)2007,JPO&INPIT