| 摘要 |
PURPOSE:To set a tip clearance between two rotors to zero and thereby improve the discharge capacity of a pump by using metal or ceramics for an inner rotor and elastically deformable resin for an outer rotor, respectively. CONSTITUTION:Two rotors 1, 2, whose tooth number difference is one each, are combined together and thereby an internal gear rotor 4, producing a pumping chamber 3 between tooth surfaces of these rotors, is constituted. The inner rotor 1 may be any mechanical works of metal as iron or the like, but a part of ferrous sintered metal is better in view of manufacturability. As for material for the outer rotor 2, acrylonitrile-butadiene-styrene (ABS) resin may be used, but an engineering plastic resistible to a temperature of more than 100 deg.C is preferable to that. With this, harmonizability in engagement is very good and, what is more, sliding resistance can be made smaller. |
