US Patent 7641457 Internal gear pump

The invention relates to an internal gear pump including: a rotor member including an outer rotor provided with inner teeth to which a torque supplied from a driving device is transmittable; an inner rotor provided with outer teeth engageable with the inner teeth of the outer rotor so to be driven by a rotation of the outer rotor, wherein a rotation axis of the inner rotor is eccentric with respect to a center of the rotor member; a pair of housings provided on opposite sides of the rotor member and the inner rotor to support the rotor member and the inner rotor; and at least one rolling bearing provided between at least one of the housings and the rotor member.