SINGLE-BARREL DUAL-CAVITY INJECTION PUMP, INJECTION PUMP MECHANISM, AND OPERATING METHOD

A single-barrel dual-cavity injection pump, comprising a pump body bushing (2), an injection shaft (3), a housing (1), and a sealing apparatus (6). A cylindrical hole is provided at an extremity of the housing. The pump body bushing is provided within the cylindrical hole. The injection shaft is provided in the pump body bushing. Two rectangular grooves (3-1 and 3-2) are provided on the outer sidewall of the injection shaft. The two grooves are closed at one extremity and opened at the other extremity and respectively are in flush with either extremity of the injection shaft. The outer wall of the injection shaft tightly fits the inner wall of the pump body bushing. A medium inlet extremity (1-1) and a medium outlet extremity (1-2) in communication with either groove respectively are provided on the pump body bushing. An inlet and an outlet in communication with the medium inlet extremity and the medium outlet extremity of the pump body bushing are provided on the housing. An extremity of the pump body bushin