Injection mold design includes design of the optimum ejection system to meet part specification. While ejector pins are most commonly used, there are other methods of ejection systems that are required in specific situations.
Ejector pins are round, and used to extend into the cavity to push the part out during mold opening so that the parts fall out or are pulled out by a robot. Pins are adequate in most situations, although some part designs require pins along with an alternative method, or a different method altogether.
Ejector blades can also be used for ejection if the part design requires it, and these have more of a rectangular geometry. Ejector blades are often used in designs where a thin wall exists, thus an ejector pin may damage the part with force or pressure applied in a critical area.
Ejection sleeves are tubular, and are ideal in areas of raised surfaces. These raised surfaces are designed to assist with assembly in some designs, for example a raised hole at the end of a vertical part would be referred to as a boss. Ejection sleeves provide 360° surface around the boss for easy part ejection with these types of part designs.
A stripper plate is another type of ejection system that consists of an entirely separate moving plate, that is designed to strip the part or parts from the core of the mold. These are ideal in situations where you need to keep parts and runners separate, and are utilized in three-plate tool.
Michiana Global Mold is a leading global injection mold design and construction company, with extensive experience in all types of ejection systems. Our skilled mold designers and journeyman mold makers have extensive knowledge and experience with various types of mold construction. We construct prototype molds with sample parts, cold runner or hot runner tools, shuttle molds, insert cavities and all aspects of injection mold design including engineering changes.
Michiana Global Mold was established in Indiana in 1964, serving various industries and specializing in complex, precision tools for the Automotive industry. We offer a partner company in China with offshore mold making capabilities. Both facilities are registered to ISO 9001 and follow strict quality management systems. Contact us today for a FREE design consultation and to speak with a skilled design engineer.