An injection assembly (1) of a die casting machine comprises valve means for controlling the advancement and return of the injection piston (20) and of the multiplier piston (42). The valve means comprise a plurality of valves, including a proportional delivery valve (104), a proportional injection discharge valve (112) and a proportional multiplier valve (118). Electronic control means (300) are provided which are configured and/or programmed to execute an air purge cycle which performs the opening and closing of the valves, alternately, for a predetermined number of times.

An injection assembly (1) of a die casting machine comprises valve means for controlling the advancement and return of the injection piston (20) and of the multiplier piston (42). The valve means comprise a plurality of valves, including a proportional delivery valve (104), a proportional injection discharge valve (112) and a proportional multiplier valve (118). Electronic control means (300) are provided which are configured and/or programmed to execute an air purge cycle which performs the opening and closing of the valves, alternately, for a predetermined number of times.

A molding machine teaching aid includes a frame unit, a molding unit, a material supply unit, a drive unit and a monitoring unit. The molding unit includes a fixed die holder, a movable die holder, and two die kernels respectively and detachably disposed on the fixed and movable die holders. The material supply unit includes a heating module for melting a wire material, and an extruder transporting the molten material into a die cavity formed between the die kernels. The drive unit is controllable to drive movement of the movable die holder relative to the frame unit. The monitoring unit is for a user to operate to control the extruder, the heating module and the drive unit.

A die casting machine of an embodiment includes: a holding furnace holding molten metal; a sleeve located outside the holding furnace and having a molten metal supply port passing through a mold; a plunger sliding through the sleeve and including a plunger rod and a plunger tip fixed to a tip of the plunger rod; a molten metal supply pipe pushed against the sleeve to cover the molten metal supply port and supplying the molten metal into the sleeve; and a pushing force variable mechanism reducing a pushing force for the sleeve in the molten metal supply pipe when the plunger is sliding.

A die casting machine of an embodiment includes: a holding furnace holding molten metal; a sleeve located outside the holding furnace and having a molten metal supply port passing through a mold; a plunger sliding through the sleeve and including a plunger rod and a plunger tip fixed to a tip of the plunger rod; a molten metal supply pipe pushed against the sleeve to cover the molten metal supply port and supplying the molten metal into the sleeve; and a pushing force variable mechanism reducing a pushing force for the sleeve in the molten metal supply pipe when the plunger is sliding.

A gap control part controls a clamping device so that mating surfaces in a die face each other across a gap, and thereby a cavity and an external part of the die communicate across the gap. A molten metal feed control part controls a molten metal feed device so as to feed molten metal into a sleeve when the gap is being maintained. An injection control part controls an injection device so as to start a forward movement of a plunger at a time when the gap is maintained and there is the molten metal in the sleeve. A clamping control part controls a clamping device so as to make the mating surfaces abut against each other to eliminate the gap after the forward movement of the plunger is started and before the molten metal reaches a molten metal surface height at which the molten metal flows into the gap.

A gap control part controls a clamping device so that mating surfaces in a die face each other across a gap, and thereby a cavity and an external part of the die communicate across the gap. A molten metal feed control part controls a molten metal feed device so as to feed molten metal into a sleeve when the gap is being maintained. An injection control part controls an injection device so as to start a forward movement of a plunger at a time when the gap is maintained and there is the molten metal in the sleeve. A clamping control part controls a clamping device so as to make the mating surfaces abut against each other to eliminate the gap after the forward movement of the plunger is started and before the molten metal reaches a molten metal surface height at which the molten metal flows into the gap.

A die casting machine of an embodiment includes: a holding furnace holding molten metal; a sleeve located outside the holding furnace and having a molten metal supply port passing through a mold; a plunger sliding through the sleeve and including a plunger rod and a plunger tip fixed to a tip of the plunger rod; a molten metal supply pipe supplying the molten metal into the sleeve and attachable to and detachable from the molten metal supply port; and a moving mechanism detaching the molten metal supply pipe from the molten metal supply port when the plunger is sliding.

A die casting machine of an embodiment includes: a holding furnace holding molten metal; a sleeve located outside the holding furnace and having a molten metal supply port passing through a mold; a plunger sliding through the sleeve and including a plunger rod and a plunger tip fixed to a tip of the plunger rod; a molten metal supply pipe supplying the molten metal into the sleeve and attachable to and detachable from the molten metal supply port; and a moving mechanism detaching the molten metal supply pipe from the molten metal supply port when the plunger is sliding.

An injection device of a light metal injection molding machine includes: a first inert gas storage part creating an inert gas atmosphere around a plunger insertion port of an injection cylinder; a second inert gas storage part housing surplus molten metal in a melting cylinder and creating an inert gas atmosphere above the molten metal; and a first pressure adjustment part adjusting a pressure in the first inert gas storage part to a pressure equal to or less than a pressure obtained by adding a pressure, which is determined based on a value obtained by multiplying a specific gravity of the molten metal by a height difference between a highest position and a lowest position of the molten metal in a part that includes the inside of the injection cylinder and communicates with the inside of the injection cylinder, and a pressure in the second inert gas storage part.