Co-injection molding structure

A co-injection molding structure, comprising:

• a co-injection molding device, including a cylinder block, a valve needle, a first feed tube and a second feed tube, wherein an accommodating space is arranged axially inside the cylinder block, the accommodating space communicates with the outside with a first runner, a second runner and a nozzle, the valve needle is arranged in the accommodating space and is operable to reciprocate between a first position and a second position in an axial direction of the cylinder block, a channel is arranged in the axial direction of the valve needle to communicate with the nozzle, the valve needle is provided with a first opening corresponding to the first runner, a second opening corresponding to the second runner, a first valve and a second valve, the inside of the first feed tube is used to contain a first material and communicates with the first runner, the inside of the second feed tube is used to contain a second material and communicate with the second runner;
• and
• a molding die, including a first mold and a second mold operable to be coupled or separated, wherein the first mold is coupled to the second mold to form a mold cavity, and the mold cavity has a sprue connected to the nozzle of the co-injection molding device,
• whereby when the valve needle is in the first position, the second valve closes the second runner, and the first material of the first feed tube enters the channel through the first runner and the first opening and is injected into the mold cavity by the nozzle;
• when the valve needle is displaced from the first position to the second position, the first valve closes the first runner, and the second material of the second feed tube enters the channel through the second runner and the second opening, is injected into the mold cavity by the nozzle, is covered by the first material, and pushes the first material to flow to an end of the mold cavity.