To stably feed the resin for lubrication by providing a passage for bearing lubricant in which the high pressure molten resin small in pressure fluctuation is introduced from a part away from a gear part on the pump discharge side of a pump housing and lead to a journal part to suppress the pressure fluctuation of the molten resin for lubrication.
A gear pump 1 to pressurize the resin which is kneaded and melted in a kneading machine and feed it to a pelletizer, is provided with a pair of two gear rotors 10 and 10 stored in a pump housing 9, and a gear part 20 is integrated with an outer circumference of a maximum diameter part of an intermediate part of a shaft part 11 in each gear rotor 10. A passage 22 for bearing lubricant is formed in the gear pump 1, and comprises a passage 23 on a discharge port side of the pump housing 9 and a passage 24 on a journal part side. An inlet of the passage 23 is opened in an inner wall at a part away from a tooth of the gear part 20 at the discharge port, and capable of feeding the molten resin of the prescribed high pressure is fed to the journal part to demonstrate the stable lubricating function.
FUKUMIZU SHINICHI
NAGAMI NOBUKI
IRITANI KAZUO
