Patent ID: 7507065
Filing Date: 2009-03-24
Classification: F02M,F04D

Abstract:
1. A fuel pump comprising a casing and a substantially disc-shaped impeller rotating within the casing, wherein; a first group of concavities is formed in a lower face of the impeller, the first group of concavities being formed in an area located inwardly from the outer circumferential face of the impeller by a predetermined distance; a second group of concavities is formed in an upper face of the impeller, the second group of concavities being formed in an area located inwardly from the outer circumferential face of the impeller by a predetermined distance, bottom portions of the pair of first and second concavities being in communication with each other; a first groove is formed in the inner face of the casing opposite the lower face of the impeller, the first groove being formed in a region opposite the first group of concavities in the impeller and extending from an upstream end to a downstream end; a second groove is formed in the inner face of the casing opposite the upper face of the impeller, the second groove being formed in a region opposite the second group of concavities in the impeller and extending from an upstream end to a downstream end; a suction hole is formed passing through the casing for communicating the upstream end of the first groove to the exterior of the casing, the suction hole being connected to the upstream end of the first groove and not in connection with the second groove; a discharge hole is formed passing through the casing for communicating the downstream end of the second groove to the exterior of the casing, the discharge hole being connected to the downstream end of the second groove and not in connection to the first groove; and wherein, the depth of the first group of concavities and the depth of the second group of concavities are substantially identical, and the depth of the first groove is deeper that the depth of the second groove.