Crescent pump for supplying lubricating oil for internal-combustion engine, has sickle with circular arc-shaped front and rear internal contour areas during pumping operation of pump, where areas exhibit different larger radius

摘要

The pump (1) has an outer wheel (3) comprising internal teeth (7), and an inner wheel (4) arranged eccentric to the outer wheel and provided with external teeth (9). A sickle (13) is arranged in a gap (38) with respect to a combing engagement (11) of wheels (3, 4). The sickle includes a circular arc-shaped front internal contour area (19) and a circular arc-shaped rear internal contour area (20) with respect to rotational directions (15, 16) of the wheels during pumping operation of the pump, where the front and rear internal contour areas exhibit different larger radius.