An injection apparatus of one embodiment includes a cylinder, a screw provided inside the cylinder, and a drive mechanism configured to rotate the screw, move the screw forward, and move the screw backward. The drive mechanism includes a piston having a piston rod and a rotating body which is arranged around the piston rod and is driven to rotate around a central axis of the piston rod as a rotation axis. A plurality of external teeth extending in the direction of the central axis of the piston rod are provided on the piston rod, and a plurality of internal teeth meshing with the external teeth are provided on the rotating body. Also, the screw is non-rotatably connected to a distal end side of the piston rod.

Disclosed is an oil-electricity hybrid injection molding machine, including a base, a feeding barrel, a screw rod and a power system. The oil-electricity hybrid injection molding machine utilizes a dual clutch combination with coaxial arrangement to enable the use of the same motor for injection and feeding, thereby reducing the selection specifications of the motor; on the other hand, through the use of auxiliary oil cylinders, under the oil-electricity hybrid power, the pressure, speed, and accuracy of the injection can be ensured, especially during injection.

After the injection shaft moves backward and the gas is supplied into the injection chamber, it is desired to accurately control the gas supply amount in the injection device in which the injection shaft is moved forward to compress and dissolve the gas in the molding material in the injection chamber. An injection device of the disclosure supplies a gas into an injection chamber via a gas supply hole which passes through an injection shaft and is opened at a tip surface of the injection shaft. The injection device of the disclosure has at least one seal ring and at least one piston ring aligned in an axial direction on an outer circumferential surface of the injection shaft.

A vibration sensor detects first data of a first component group and second data of a second component group. An injection molding machine performs diagnosis processing for diagnosing the first component group based on the first data in an injection mode and performs diagnosis processing for diagnosing the second component group based on the second data in a plasticization mode.