The invention provides an externally controlled mold opening and closing oil circuit for a vertical injection blow molding machine, aiming to solve the problems of unstable downward movement of an oil cylinder during mold closing, abnormal noise during upward movement of the oil cylinder, and sliding after upward movement stops. The oil circuit comprises: an externally controlled oil circuit, an oil cylinder, an oil inlet circuit, an oil return circuit and a servo motor. The invention provides corresponding opening pressure for a valve core through the externally controlled oil circuit, ensuring the stability of the hydraulic system, thereby avoiding jitter and crawling of the injection blow molding machine during mold closing. Meanwhile, a pilot-operated check valve and a safety cartridge valve are added in the oil circuit, which can prevent sliding after the oil cylinder moves upward and stops, and avoid sudden opening and closing of the valve core during mold opening and closing, improving the safety level of the vertical injection blow molding machine.

Country Code: CN

Application Number: CN201810871169.2