Design of the ejection system: the concept of the ejection system in every cycle of the injection molding, the plastic parts must be removed from the mold, The mechanism for removing this action is known as the ejection system (also known as the ejection mechanism). 2: the type of ejection device is 1D: the dome needle is 2n: the square thimble (flat thimble) is 3n: the dome (sleeve) is 4m: the inclined top (slant pin) 5s: the pushing plate (top block). ): air top 7: double thimble 3: determination of ejection stroke 1. Ejection stroke is generally stipulated in the ejection of finished products from the die 5-10, the final ejection stroke to take 5 times. 2. In the shape of some simple shape and angle of release. When it comes to barrel products with a greater degree, The ejection stroke can be determined as 2 / 3 of the product depth.
The design principle of ejection system 1. The motion of ejection mechanism should be accurate, reliable and flexible, and the mechanism itself should have sufficient strength and stiffness. Enough to overcome the demoulding resistance. 2. To ensure that the plastic parts do not deform during the ejection process. 3. After cooling, because the plastic parts will produce shrinkage stress on the kernel, there is a phenomenon of holding tight, and the thickness strength of the finished meat on both sides of the broken hole is the weakest. Thimble should be set up. 4. Thimble should be set directly below the vertical wall thickness of finished product to facilitate demoulding. 5. Under "cross rib", thimble should be set up under "cross rib". 6. When using common die side thimble, we should pay attention to die kernel strength, The minimum distance from the thimble to the edge of the die is 0.8 7. When selecting the thimble, the diameter of the thimble is as large as possible within the allowable range, and it is a standard product. For processing cost and time. 8. Smaller than the 3mm of the thimble must be made into a double thimble.