Patent ID: 6120243
Filing Date: 2000-09-19
Classification: F04D,F05C,F16N

Abstract:
A pump comprising a housing having a shaft bore and a pump chamber, a bearing provided for an inner periphery of the shaft bore, a shaft rotatively supported by the shaft bore through the bearing, and an impeller connected to one end portion of the shaft for transporting fluid by imparting mechanical energy to the fluid sucked in the pump chamber,the bearing being constituted as a sliding bearing, and said impeller being arranged off-set inside the housing and constructed such that a high-pressure portion and a low-pressure portion of lower pressure than the high-pressure portion being formed inside the pump chamber when a fluid passage is formed, a first region of a sliding surface formed to said sliding bearing being communicated with the high-pressure portion to be formed so as to provide a high pressure when constructed as the fluid passage, while a second region of the sliding surface formed to said sliding bearing being communicated with the low-pressure portion to be formed so as to have a relatively lower pressure than that of said high-pressure portion when constructed as the fluid passage, so that the fluid is supplied to the sliding surface of said sliding bearing by the action of a differential pressure between the high-pressure portion and the low-pressure portion of the fluid passage so as to lubricate said sliding surface.