In the design, some structures are very representative, and it is easy to make practice and perfect. The following example is the case, including double-section change, delay core-pulling, and pumping structure similar to Huff.

 

Model number: C06034, C06035
Product Name:Lower Finish Panel
Compound: PC/ABS
Shrinkage rate: 1.006
Number of cavities: 1
Die life: 500,000 times
Product Dimensions: 96.31X245.72X134.15

There are multiple column positions and hole positions on product, so axial direction of column position and hole position is taken as mold exit direction. As shown in above figure, red surface is glue surface on fixed side of product, and blue surface is glue surface on movable mold. Structure of product on the mold is analyzed according to product's die-out direction. It can be seen that two sliders are needed on both sides of product, and shape of one side of product is as shown in figure (shapes on both sides are same)

 

There is a circle of bone below round hole, which is at two angles with direction of die. As shown in figure, blue surface is rear mold surface, red face is reverse button face, and there are two square holes on both sides. Therefore, it is necessary to design a special core-pulling mechanism to form glue position here.

 

Name of core-pulling mechanism can be referred to as a one-turn four-delay core pull slider.

 

Two holes on both sides of product circumference are formed by two active small rows.

 

Small slider forms a sliding fit with outer movable sleeve and lateral 7-shaped ears, and small slider can slide with sleeve in the direction of 7-shaped guide groove.

 

Lower end of small slider has a J-shape, which cooperates with a rectangular hole in the center insert and can be relatively slid.

 

Therefore, there is relative movement between two small rows and movable sleeve, between small row position and central insert, between central insert and movable sleeve. Their power and motion sequence control are derived from large position underneath, and large line is driven by cylinder.

1. Movable sleeve slides down, small slider is pulled off buckle, and center insert does not move. Lower end of red movable sleeve and large sliding block are connected by a T-shaped groove with a slope, upper part of step is a sliding fit of straight body surface and rear mold, and rear end of large sliding block is screwed with oil cylinder.

 

After mold is opened, cylinder is pulsed backward, large slider is pulled back together, and movable sleeve falls back along core pulling direction under action of inclined T-shaped groove. Large slider and center insert have a flat contact for controlling delayed core-pulling. During beginning of retreat of cylinder, due to position of plane, central insert is stationary relative to mold and product, and movable sleeve slides between mold and central insert.

 

Two small sliders on head are matched with sleeve through 7-shaped groove. Direction of 7-shaped groove is at an angle with respect to moving direction of sleeve. Lower end of small slider is J-shaped and has a rectangular cross section, both sliders are slidingly matched with central insert. When sliding sleeve is twitched downward, small slider is pulled outward by action of 7-shaped groove and central insert hole to take out inverted buckle.

 

Relative position of small slider after core-pulling:

 

2. Small slider, center insert and movable sleeve are retracted together to extract all inverted surfaces. After small slider is pulled away by a safe distance, central insert walks over horizontal distance on large slider. At this time, center is set to pass through step surface of lower stage, and is driven by sleeve to move relative to T-slot inclined surface of large slider along direction of mold sleeve hole.

 

Two small sliders are also moved down by sleeve and central insert until all moving parts are completely disengaged from product glue level, and core pulling action is completed. Relative position of small slider, movable sleeve and center insert after core is completed is as follows:

 

After core-pulling operation is completed, product is ejected by ejector pin.

 

As shown in above figure, A is reverse distance of product, and stroke of small slider is C. Due to space limitation, stroke of small slider is equal to product reverse buckle plus 0.5mm, that is, C=A+0.5, B is stroke of movable sleeve in first core pulling. C is stroke of small slider, that is, core-pulling distance. And M is angle between 7-shaped groove and moving direction of movable sleeve. Three sides of B, C, and L form a right-angled triangle. When determining stroke, above right-angled triangles are directly drawn, and required lengths can be obtained according to known conditions.

As shown in figure below, B is delay distance of center insert, that is core distance of the first core of movable sleeve, and D is sliding distance of center insert on the plane of large slider, E is distance that movable sleeve slides in slope T slot of large slider. Three sides of B, E, and F form a triangle. We can find values of F and E based on known condition B and angle G.

 

In figure below, H is product buckle, J is center insert core stroke, J is greater than or equal to H+2mm, K is large slider movement distance, I is distance that movable sleeve and center insert slide together in slope T groove of large slider, and N is angle between T-slot and direction of movement of large slider. In figure, I, J, and K form a triangle together. We can find values of K and I based on known condition H and angle N.

 

When we choose cylinder model, we must know working stroke of cylinder. In this case, working stroke of cylinder is total moving distance of large slider: K+F, and then select cylinder according to calculation result plus margin of 10 to 20MM.

 

Summary: Today introduced a more ingenious joint core pulling action, so that product design that was originally considered impossible to achieve has become a reality, fully realize customer's product design intent, is a relatively classic injection mold core structure.