A runner for supplying resin to a cavity includes a sprue that is supplied resin from a nozzle of an injection molding machine, a first path formed in the runner, where the resin flows in the first path from the nozzle when the nozzle connects to the sprue, a first pin that moves to a first position to increase the size of the first path before the resin is supplied to the first path and moves to a second position to decrease the size of the first path before the nozzle separates from the sprue.

A runner for supplying resin to a cavity includes a sprue that is supplied resin from a nozzle of an injection molding machine, a first path formed in the runner, where the resin flows in the first path from the nozzle when the nozzle connects to the sprue, a first pin that moves to a first position to increase the size of the first path before the resin is supplied to the first path and moves to a second position to decrease the size of the first path before the nozzle separates from the sprue.

In a plastic injection machine, a controller in electrical communication with a motorized clamp assembly, a heated cylinder barrel, a motorized pre-plasticizing assembly, an injection assembly, and an air mover and that executes an application that configures the controller to: (i) feed thermoplastic material into a heated cylinder barrel that is closed at one end by an injection valve; (ii) warm the heated cylinder barrel to thermoplastic material to a liquid state; (iii) actuate an injection motor to preload a spring biased plunger received within another end of the heated cylinder barrel, thereby pressurizing liquid thermoplastic material in the heating cylinder barrel to an injection pressure set value; (iv) actuate an injection valve motor to open the injection valve causing the pressurized liquid thermoplastic material to inject into a clamped mold; and (v) release a portion of the clamped mold to release the molded article.