1. Pressing the wire into the substructure
The purpose of crimping: (1). Pre-deform the material to reduce the resistance during bending and make the dimensions during bending more accurate. (2). Prevent the deformation of the material during bending. 2. The purpose of pressing the ribs into the substructure is to reduce the springback during bending and make the bending dimensions more accurate. Reduce the deformation of the material during bending.
Note: When the slider is used for bending and forming, the slider must be reinforced.
3. Press burrs into the machine (1) Press burrs in the inner hole and press burrs around the product. (2) The processing method of pressing the burr. First, cut the shape of the insert, put the insert into the insert hole of the template, raise the bottom by 0.22mm, and use a Φ4 ball cutter to process around the insert. The size is shown in the figure below. . (Material thickness is 0.8T) 4. The material part of the pre-cut structure continuous mold is sheared or sheared at the last station. The product requires no burrs in appearance or touchable parts, so the mold is required to be cut at the previous station. Pre-cut (also called pre-burr). When designing, you must first determine the direction of the burrs and determine whether to pre-cut on the upper mold or the lower mold. Its structure and specific design dimensions are as follows: 5. Operation instructions for the continuous shearing and bending structure: cut first and then fold the knife edge to a height of one material thickness. The inclination is 1.5 degrees to reduce the contact surface between the punch and the notch to reduce friction. The bottom of the punch cut is 2mm straight to ensure the strength of the blade and prevent edge chipping. The punch bending edge height is 1.5T, which ensures cutting first and then folding. 6. Elevator pin design standards
1. Selection principles (1). Generally, the LB type ejector pin with Φ8.0 is selected. If the space is not enough, a Φ6.0 type ejector pin can be used. (2). When the required ejection force is large and the position is sufficient, a Φ10.0 ejection pin can be used. (3). When selecting the ejection pin length, attention should be paid to the following principles: a. Select standard length. And consider whether there is no need to countersink holes in the formwork. b. When the ejection height is <=10MM, generally use the ejector pin of Φ8.0; when the ejection height is >=10.0MM, select other standard specifications of the ejection pin. c. Avoid the spring from pressing against the steps of the template when opening the mold. phenomenon. d. The LB-type ejector pin made of Teflon is suitable for aluminum, copper and other materials. The specifications are Φ8.0*25, Φ8.0*30, Φ8.0*35, Φ8.0*402. Arrangement rules (1) Drawing holes and ejector pins are arranged symmetrically around the drawing convex, and inner stripping can also be used for stripping. (2) If an ejector pin is used to remove the material during bending, an ejector pin should be arranged every 20-30MM on the bending edge of the punch. An ejector pin must be arranged at the bending corner. Four ejector pins must be arranged. The distance between the dividing points and the bending edge is 2.5MM. (3) When folding one edge, the ejector pins on the bending edge are arranged according to the above principles, and 2-4 ejector pins are evenly distributed on the non-bent edge depending on the size. The arrangement of the ejector pins generally ensures that the distance from the escape hole edge of the ejector pin to the material edge or the corresponding cutting edge edge of the mold is 4MM. Please note that the position and size should be rounded to an integer or one decimal place as much as possible. Generally, there are two ejector pins arranged symmetrically on both sides of the inner hole precision positioning pin. The precise positioning of the appearance can be determined according to the need whether to install the ejector pins. In addition, the arrangement of the ejector pins must also consider the stability of the entire workpiece. 7. Salad hole design standards 1. Salad hole forming steps: a. Salad first and then punch b. Punch first and then punch c. Punch first hole, make a salad, and then punch 2. There are two types of salad holes: a. Shallow salad holes: Shallow salad holes are divided into three steps. The first step is to punch the bottom hole first, the second step is to punch the salad hole, and the third step is to punch the bottom hole. In the third step, punch the salad through hole. The specific size is shown in the figure below. b. Deep salad hole: The deep salad hole is divided into two steps. The first step is to punch the bottom hole first. The second step is to punch the salad hole. 8. Slide Block structure design standards 1. The commonly used slide block fixing forms are as follows: a. Suitable for small and medium-sized slide blocks, relying on the vertical side limit of the slide block (Figure 1); b. Suitable for large-scale slide blocks processed in a shared manner. The slide block and the limit block adopt the block form (as shown in Figure 2); c. Suitable for large and medium-sized slide blocks that need to be quickly loaded and unloaded, relying on the limit plate at the bottom of the slide block (as shown in Figure 3); d. Suitable for needs When the slider is reset before contacting the material, the slider is reset first by the ejection pin in the slider. The length of the ejection pin is usually 7mm, with a protruding end surface of 2.0mm, and a red flat wire spring is used. (Figure 4) e. Suitable for blocks that require the middle vertical p to move up and down, and the left and right sliders to move horizontally. The middle slider relies on the inner guide post to guide the left and right sliders with equal height sleeves to limit the length of the equal height sleeves. Take the thickness of the plywood and add 0.5mm. (Figure 52. General structure and dimensions of sliders (1) For large sliders and templates, the outer angle is usually R1.0 and the inner angle is R0.8, as shown in Figure (9); for small sliders and templates, the outer angle is R1.0. Take R0.3 (2) for the inner angle of R0.5. Figures (7) (8) are the commonly used structural forms of sliders. (3) Figure (6) is used when the size of the slider is small and the dovetail cannot be set, or the figure ( 7) In the form of (8), when the template interferes with the size of the slider in the W direction, the dimensions A, B, C, and D in the figure are generally at least 3mm; (4) The slider fitting clearance (the hatched part in the figure): a. Material When the thickness is greater than or equal to 0.6, the corresponding unilateral gap of the template is enlarged by 0.03, and the slider does not leave the gap; b. When the material thickness is less than 0.6, the corresponding unilateral gap of the template is enlarged by 0.02, and the slider does not leave the gap; c. Large and medium-sized sliders When cutting and sharing, the designer only needs to draw the theoretical shape of the slider. The step section and clearance at the shared location are handled by the processing department. The matching clearance of the shared slider is generally 0.02. (5) When the slider bevel angle P is within 15 degrees. It can be chosen at will; when it is greater than 15 degrees, only 30 degrees and 45 degrees can be selected, and the bevel angle cannot exceed 45 degrees. (6) The slider bevel angle is preferably 5°, 10°, 30°, or 45°. Specifications. 3. Slider design considerations
a. The vertical movement stroke of the slider should generally not be greater than half of the thickness of the slider; b. In order to ensure reliable movement of the slider, an appropriate number of lifting pins or springs should be arranged on the top of the slider; c. When the slider is processed in a shared form, The two sliders should be rotated 180 degrees around the center of the template for processing. At this time, the designer does not need to rotate the graphics elements, and the adjustment work is handled by the processing department themselves; d. As shown in Figure (12), when there is a small slider in the middle of the template At this time, if the slope of the slider is less than or equal to 15 degrees, the guide chute can be cut directly on the template; if the slope of the slider is greater than 15 degrees, it is best to change the guide groove on the template into a block form. 9. Design standards for rollers and folding knives 1. Generally speaking, the roller should be Φ8.00. In special cases, Φ6.00 or Φ4.00 can be used. If the rollers are not processed, no drawing is required. 2. The folding knife uses a plywood with milled grooves and is fixed with hexagonal socket screws (M10). The value of H is less than the thickness of the inner stripping plate. The function of internal grinding 0.1 on the upper part of the folding knife is mainly to prevent the folding knife from scratching the material. When there is an inner guide post, the gap between the folding knife and the inner stripping plate is +0.1. When there is no inner guide post, the gap between the folding knife and the inner stripping plate is 0.02. 10. Side edge positioning design standards 1. In mold design, in order to ensure accurate material feeding, Use pitch positioning to ensure the material feeding step. There are generally two methods of pitch positioning: tongue cutting and side edge positioning. Due to the use of side edge positioning, the dimensions are stable and can be used regularly. 2. The width e of the material sheared by the side blade is 2.0mm for general materials; the value e is 1.5mm for punching and shearing thin materials (T≦0.3mm). The gap between the side edge positioning block and the punch is 0.01mm.; the gap between the side edge positioning block and the punched and sheared material is 0.03mm. For the size of the side blade positioning block, please refer to the standard part "Pitch Positioning Block". Please see (Figure 1) for structural details: 11. Limiting column design standards 1. In mold design, in order to prevent the mold from damaging parts during air punching, such as letter molds, pressure lines, and some special mold force inaccuracies When the balance is reached, limit posts are added to withstand the force. 2. The limit methods can be divided into two types: in-mold limit and out-mold limit. Generally, Φ20 is used for the in-mold limit, while Φ30 and Φ40 are used for the out-of-mold position. 3. Please refer to the standard part "Limiting Column" for the body dimensions of the limiting column. 4. For the height of the limit column, if it is a character mold, the limit column must be printed on the pressure line. You only need to protrude the template (0.6~0.8T) inside the mold, and add the limit column outside the mold. The height of the upper and lower limit columns is divided equally, but they are divided into integers. It is better to have a larger height difference to prevent fooling around. 12. Design standards for dual-purpose pins 1. Select dual-purpose pins: The selection of dual-purpose lifting pins must not only consider the thickness of the material, but also the size of the mold (the principle is to give priority to the larger one). For specific dimensions, please refer to the standard product "Dual-Purpose Floating Pin". The dual-purpose lifting pin has related dimensions (as shown in the figure). 2. The relief depth of the dual-purpose lifting pin on the stripper plate directly affects the quality of the workpiece. If the relief is too deep or too shallow, the edge of the material will be crushed or even cut. In order to reduce the occurrence of this phenomenon, according to the specifications of the standard dual-purpose pin, the relief depth of the stripper plate can be determined by referring to the table in the figure. 3. When opening the mold, if the floating height of the dual-purpose lifting pin exceeds the guide length of the inner guide post when opening the mold, when the guide post leaves the lower mold, the head of the lifting pin will still be in the stripper plate. The lifting pin clearance from the plate is too small, and the mold opening force is unbalanced, which will break the lifting pin. Therefore, the clearance of the lifting pin from the plate is 2.0mm on one side. However, if the material is thin or the width of the material is too small, please determine the clearance for removing the board based on the actual situation. The lifting pin not only has the function of positioning and lifting, but also ensures smooth feeding. Therefore, the gap between the material and the lifting pin before shearing is stipulated to be 0.10mm; the gap between the material and the lifting pin after shearing is 0.03mm. . 13. Positioning design standards As product dimensional accuracy and coordination requirements are getting higher and higher, positioning cannot be ignored when designing molds. 1. Positioning is divided into two types according to location: internal positioning and external positioning. 2. The gap between the inner positioning block (pin) A and the product is 0.03mm, and the gap between the outer positioning block (pin) B and the product is 0.05mm. 3. There must be symmetrical ejector pins D on both sides of the inner positioning, and the gap between them and the inner positioning is as shown in the figure. If there is no inner positioning block (pin) A, the gap between the outer positioning block B and the workpiece should be 0.03mm. 4. For external positioning, special shapes or circles can be used first according to the actual situation, but the cut edges should be used for positioning as much as possible. 5. The effective part of the outer positioning should be 3-5mm higher than the effective part of the inner positioning. 6. The clearance of the inner positioning stripper plate is +0.05mm. The clearance of the outer positioning stripper plate is +0.5mm. The clearance of the special-shaped outer positioning stripper plate is +0.1mm.
Several commonly used forms of tooth extraction are shown in the figure below: (The upward and downward tooth extraction punches are all the same length, making it easy to replace)
14. Extraction tooth structure design standards and extraction tooth production standards: The calculation principle of extraction tooth is the principle of constant volume. Generally, the height of extraction hole is H=3P (P is the tooth distance). R=EF﹐∵T*AB=(H-EF)EF+π*EF*EF/4,∴AB={H*EF+(π/4-1)EF*EF,∴Pre-punching=ψD-2AB .1. When T≦0.5, take EF=100﹪T2. When 0.5<T<0.8, take EF=70﹪T3. When T≧0.8, take EF=65﹪T
Several commonly used forms of tooth extraction are shown in the figure below: (The lengths of the upward and downward tooth extraction punches are the same, making them easy to replace)
15. Strip notch design standards 1. When designing the continuous mold, it is considered that the strip will have gaps due to poor feeding, or secondary shearing will produce burrs, so a process gap will be added during the design to overcome the above problems. 2. Standard form of notch: if the shearing punch exceeds 0.3mm, burrs caused by uncut can be avoided. 3. The schematic diagram is as follows:
