Unconsciously, I have been in the 19th year. It’s really not a long time. The majority of friends at Dongguan Mould Factory are coming to the peak of financial activities. The editor of Dongguan Plastic Mould Factory has not updated the website for you for a long time. Today, I will introduce the design points of the guide pillar guiding mechanism in the manufacture of plastic molds.
Small molds generally only have two guide columns. When the orientation of the element is required, the method of equal diameter and symmetrical arrangement is adopted. If there is a clamping position requirement, an equal diameter asymmetric arrangement or unequal diameter arrangement should be adopted. form. Large and medium-sized molds are often provided with three or four guide columns, which are arranged in an equal-diameter asymmetric arrangement or in an unequal-diameter arrangement.
Straight guide sleeves are often used in simple molds or thin molds; Type I lead guides are mainly used in the machining of complex molds or large and medium molds; Type II lead guides are mainly used in the guiding of the push mechanism. .
The guiding parts should be distributed reasonably around or near the edge of the mold; the distance δ from the center of the guiding column to the edge of the template is generally 1~1.5 times the diameter of the fixed end of the guiding column; the setting position can be found in the standard mold base series.
The guide post is often fixed in the mold part which is convenient for demoulding and taking out parts; however, for some special requirements, for example, the plastic part is demolded on the movable mold side by the pusher plate, in order to guide and support the pusher plate, A guide post is arranged on the movable mold side.
In order to ensure that the parting surface of the mold clamping is well fitted, the guide post and the guide sleeve should be provided with chip-receiving grooves at the parting surface; generally one side is cut off, or the hole of the guide sleeve is chamfered.
The length of the working part of the guide post should be 6~8mm higher than the height of the core end face to ensure its guiding effect.
It should be ensured that the axes of the guide columns, guide sleeves and guide holes are parallel, and the coaxiality requirements, otherwise the accuracy of the mold clamping will be affected, and even the guide parts will be damaged.
The matching precision of the working part of the guide post is H7/f7 (H8/f8 or H9/f9 can be used for low precision); the matching precision of the fixed part of the guide post is H7/k6 (or H7/m6). The transition between the guide sleeve and the mounting is generally done with H7/m6, and the lateral screws are used to prevent it from being pulled out.
For molds with small production batch size and low precision requirements, the guide post can be directly matched with the guide holes processed on the template. Generally, the guide hole should be made as a through hole; if the cavity plate is extremely thick and the guide hole is made into a blind hole, a vent hole should be added to the side wall of the blind hole, or the exhaust hole should be ground at the open end of the guide column and the guide hole. Slot; the length and surface roughness of the guiding surface of the guiding hole can be taken according to the size of the guide sleeve of the same specification, and the length exceeding the part should be expanded to shorten the sliding surface.
Note: The above information from the Jiezheng mold finishing on the Internet, welcome reproduced, indicate the source!