1. Mold Design:
Initially, a mold must be designed and fabricated to shape the LED lamp. This mold generally has two parts: a fixed part (the stationary mold) and a movable part (the moving mold). The shape of the cavity within the mold dictates the final shape of the LED lamp after the injection molding process.
2. Material Preparation:
- Appropriate plastic materials are chosen, typically transparent or semi-transparent plastics like polycarbonate (PC) or polymethyl methacrylate (PMMA), due to their excellent optical properties and durability.
- Plastic pellets are fed into the hopper of the injection molding machine, where they are heated to a molten state by the machine’s heaters.
3. Injection Process:
The molten plastic is injected into the mold cavity through a process that includes four main stages: injection, holding pressure, cooling, and mold opening.
- Injection Stage: The screw mechanism pushes the molten plastic into the mold cavity.
- Holding Pressure Stage: Once the cavity is filled, pressure is maintained to ensure the material is completely filled and to prevent shrinkage.
- Cooling Stage: The plastic cools and solidifies inside the mold, typically assisted by the mold’s cooling system, such as water channels.
- Mold Opening Stage: The mold is opened, and the molded LED lamp housing is ejected.
4. Post-Processing:
- The LED buld removed from the mold may require post-processing tasks such as deburring, inspection, and trimming.
- Additional processing might be necessary, such as printing patterns on the housing or attaching other components.
Through this process, LED lamp housings can be mass-produced efficiently, ensuring dimensional precision and surface quality. Injection molding is a highly efficient manufacturing method, especially suitable for producing complex shapes and large volumes of plastic products.
