A drive unit for a molding machine for longitudinally displacing a movable first machine component relative to a second machine component, includes a rotationally drivable spindle mounted in a linear movement-locking manner on the second machine component, a spindle nut arranged in a rotational movement-locking manner on the first machine component for positive-locking engagement with the spindle, and a fluid chamber which at least adjoins the spindle and/or the spindle nut, and contains a lubricant. A temperature control element for controlling the temperature of the lubricant is arranged in and/or on the fluid chamber at least in areas.

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.

A drive unit for a molding machine for longitudinally displacing a movable first machine component relative to a second machine component, includes a rotationally drivable spindle mounted in a linear movement-locking manner on the second machine component, a spindle nut arranged in a rotational movement-locking manner on the first machine component for positive-locking engagement with the spindle, and a fluid chamber which at least adjoins the spindle and/or the spindle nut, and contains a lubricant. A temperature control element for controlling the temperature of the lubricant is arranged in and/or on the fluid chamber at least in areas.

The drive mechanism for a screw of an injection cylinder comprises a front plate that includes a through hole and that is connected to the injection cylinder, a movable plate that rotatably supports the screw, a ball nut that is installed in the movable plate, a ball screw that engages with the ball nut and that drives the movable plate in the axial direction of the screw, a bearing that is installed in the through hole and that rotatably supports the ball screw, a support nut that is screwed into the end of the through hole on the opposite side of the front plate from the ball nut, and bolts that are supported by the support nut. The support nut includes threaded holes that are arranged circumferentially and that pass through the support nut in the axial direction. The bolts protrude from the threaded holes to press the thrust bearing.

An injection unit comprises an injection cylinder, a screw that is housed in the injection cylinder, a front plate that is connected to the injection cylinder, a movable plate that rotatably supports the screw, a ball nut that is installed in the movable plate, ball screws that engage with the ball nut and that drive the movable plate in the axial direction of the screw, a bearing that is supported by the front plate and that rotatably supports the ball screws, and a heat insulation material that is in contact with the front plate between the injection cylinder and the front plate.