Skew pin material SK3, heat treated to HRC60.
Firstly, the required stroke L of the slider should be determined, which is limited by the undercut depth of the product.
If the height of the hook is large, the height of the slider is relatively large, and the inclined pin has a large stress range and is easy to deform and get stuck. At this time, the shape of the slider is changed so that the contact length between the slider and the tilt pin is fixed.
Slider positioning has two parts:
If the undercut area is large, the force will be large when the slider is ejected, and the strength of the inclined pin cannot be supported, so the stop surface is increased to strengthen the strength. The angle of the stop surface is based on the principle that the angle of the tilt pin is 2 degrees. The angle of the stop surface should not be smaller than that of the inclined pin, and if the angle is just right, friction will occur during the whole mold opening process, which will reduce the life of the inclined pin, and sometimes there will be the danger of collision between the slider and the stop surface when closing the mold. Because the stop surface only needs to be stressed during the injection process (the mold is completely closed), it does not need to be stressed at other times, and it is easy to open the mold at a large angle. But if it is too big, it will not add the stop effect, or the mold template needs to be wider.
In order to shorten the length of the inclined pin and ensure sufficient sliding stroke, the length of the inclined pin is designed to meet the stroke of 1.2 times. When the length of the inclined pin is within the range, the slider can be prevented from falling off. However, if the mold opening stroke exceeds the length of the inclined pin, something must be used to position the lateral movement of the slider to avoid the danger of the slider falling off or the inclined pin interrupting and damaging the mold.
Setting of anti-dropping positioning action
Determine the positioning position when clamping, and then add the stroke L to determine the limit position.
Determine the size of the positioning element.
Slider size
Slider length design
Generally, it is three times of the stroke (after sliding the stroke distance, the sliding contact distance of more than 2/3 of the slider length can still be maintained, m >；; =2/3L)
When considering the strength, the two sides (front and back) of the diagonal pin must be 20 mm apart.
When considering adding water pipes, the diameter of water pipes is generally 8mm, and the meat thickness in front is increased to 28mm(3.5D) with holes.
If the slider is divided into two sections and the sliding part is in the second section, then the design of the second section is the same as step 2. Due to the strength, the design of the first part requires the length to be at least the same as the thickness of the stopper and greater than 20mm. If water pipes are added, they must be larger than 28mm(3.5D). The second section must be (20+ thickness of the diagonal pin +20), because the stop part must be 20 mm in front of the diagonal pin.
In order to reduce the wear of the sliding part, the length of the slider is 0.5 times of the width of 65438+.
The fifth point is the suggested value, which is usually for reference only.
Die seat size
Required die holder lengthening design (goal: not to make the slider protrude from the die)
Inclined pin support method: the required extension of the formwork is slider length+1.2 * stroke.
Direct engraving (1): If the stroke of 1.2 * is greater than the thickness of the stop, the die holder needs to be lengthened by the slider length+1.2 * stroke, otherwise, the die holder needs to be lengthened by the slider length+the thickness of the stop.
Straight carving (2): Generally, the plug is strong enough. Therefore, only the required extension of the die holder is considered as the slider length+1.2 * stroke.
Plug-in locating block: if the stroke of 1.2 * is greater than the thickness of the block+the fixed part of the block (1.5* the thickness of the block), the length of the slider+1.2 * stroke; Otherwise, slider length+stopper thickness+stopper fixing part (1.5* stopper thickness). The strength calculation principle of the two inserts is the same.