Injection device, die casting machine and die casting method

The invention discloses an injection device, a die-casting machine and a die-casting method. Taking one as an example, the injection device comprises an injection barrel, a material pushing hammer, a feeding bin and a heating mechanism; an inlet, a falling material cavity, a heating cavity, an injection cavity and an outlet which communicate with one another are sequentially formed in the injection barrel in the axis direction of the injection barrel; the material pushing hammer is slidably connected to the inlet, the material pushing hammer is provided with a material pushing end, the material pushing end moves in the axis direction of the injection barrel, and the material pushing end can push materials to move to the heating cavity, the injection cavity and the outlet from the material falling cavity; the feeding bin is connected to the injection barrel, and the feeding bin is in communication with the falling material cavity; and the heating mechanism is connected to the injection barrel and surrounds the heating cavity. According to the device, heating and material injection are completed in the injection barrel, a conveying path of molten materials is short, and the molten materials are always in a lightly sealed state, such that the material oxidation condition is greatly reduced; and due to the fact that the conveying path is short, heat loss is relatively small during material conveying, the temperature difference is relatively small, and the quality of finished products is relatively good.