舌簧片沖孔落料復(fù)合模具設(shè)計(jì)【沖壓模具設(shè)計(jì)】【說(shuō)明書+CAD+PROE】,沖壓模具設(shè)計(jì),說(shuō)明書+CAD+PROE,舌簧片沖孔落料復(fù)合模具設(shè)計(jì)【沖壓模具設(shè)計(jì)】【說(shuō)明書+CAD+PROE】,簧片,沖孔,復(fù)合,模具設(shè)計(jì),沖壓,說(shuō)明書,仿單,cad,proe RED CD Blanking is the use of molds to produce separate sheet stamping processes subjects, including blanking and punching. It can be made into parts, but also for the bending, drawing, forming and other processes to prepare rough. Washed down from the Board Division on the shape of the parts required (or rough) called off the branches. The shape of the workpiece out of the hole required (red to go to waste) is called punching. Figure I-1 of the washer, from falling branches and punching two processes to complete. Production practice, we die blanking process of a certain understanding of the structure, but perceptual knowledge to rational knowledge up to truly understand the nature of the blanking process, a better design of the development process and die. The following deformation on the blanking process, the quality of stamping parts, stamping die design and stamping die size blade structural design issues discussed. . Shown in Figure 1-2 blanking by the deformation process can be seen that the composition of the punch and the upper and lower concave edge chess, material on the concave mold, punch the material deformation gradually decreased until the completion of all the separate blanking. With the punch of the external forces acting on material changes in the number of the material on the external force changes in quantity, material deformation within the continuous development. The deformation of the blanking process is divided into three stages 1, elastic deformation stage Punch contact with material force as the punch pressure, the material is elastic compression and bending, and squeeze into the die hole. Then the stress does not exceed the material yield limit, if the punch relief, material or restitution, so that elastic deformation stage. 2, plastic deformation Punch to pressure, the stress reaches the yield limit of material, some metal is squeezed into the die hole, producing plastic shear deformation, are shining maggot cut surface. For convex, concave feel there is room between the depression, it is the plastic shear deformation is also accompanied by the bending and stretching. 3, fault isolation stage Materials continue to increase external and internal stress increasing, convex, because the incision die stress concentration, shear strength over the first internal stress, micro-crack appears. Mold continuing under pressure, convex, concave mold cavities of the micro-crack edge to the material constantly within the share capital, then pulled off material separation. Such as convex, concave die gap was reasonable, the upper and lower crack coincide with each other. ' ?Stress and strain Further analysis of blanking time of stress and strain state of deformation zone and help to the understanding of the blanking process. Die and punch in the edge of the joint line to take 'cell body, "whose stress-strain diagram shown in Figure 1-3. Can be seen from the figure, it seems Metal fracture line AB that is cutting edge on-line) at 45 degrees. The main uranium direction I was pulling stress and tensile deformation, tensile stress the gold Is a fiber elongation; its vertical axis 2 is the compression stress direction and compressive deformation, the fiber extrusion pressure; in the tangential direction of the stress and strain is very small, negligible; and principal stress direction at 45. Direction to the direction of maximum shear stress between the punch and die clearance, elongation and tear off the metal, resulting in broken fracture surface roughness, and with a burr. The process can also blanking blanking force deformation curves of the figure is confirmed. Figure 2-9 (materials), is punching a 3 mm thick material punching power and punch of the curve. Can be seen from the diagram: In the process of blanking blanking force size is constantly changing. AB section of the equivalent of punching the elastic deformation stage, BC Section for the plastic deformation stage. When the material internal stress to shear strength began to crack when the material, CD segment for the crack propagation until the material isolated rupture in order teams, DE Dan launch materials introduced die mouth piece. The deformation process of blanking the red plant parts are not smooth vertical section, the section has three areas, namely, with rounded corners, bright band and the fault zone. Rounded band is in the process of blanking the beginning of plastic deformation. Since the bending and stretching metal fibers formed, soft material than hard Branch rounded large. Light zone is the second phase of deformation produced plastic shear deformation of metal forming, has a smooth vertical surface, bright band of the entire cross section of 1 / 2 to 1 / 3 of the light bandwidth of soft materials, hard materials with a narrow bright . With the mechanical properties of materials, space, mold structural changes. Fault is equivalent to the third stage of the blanking process, mainly due to the role of tensile stress, the continuous expansion of China cracks down payments second fiber extension, so a very rough surface is not smooth, and there Liaoduo. In the section on the same punch with these characteristics, but the distribution of the three regions opposite position and blanking. Blanking addition to drag a section of rough dimensions, there are points dome curved, not flat, face a burr, so blanking requirements apply only to an Blanking. Section Drawing gap Blanking time requires not only the shape of call times out of line drawing parts, there should be a certain quality requirements, quality of stamping pieces is cut surface quality, dimensional accuracy and form error. Cut surface should be flat, smooth, no crack and tear, mezzanine and other defects, glitches small parts, the surface should be flat as possible, that is a small vaulted arch, size, degree of precision required to ensure the drawings do not exceed the tolerance range. Factors that affect the quality of stamping pieces range from the actual production that, convex, concave die gap size and power uniformity, pattern edge state, the mold structure and manufacturing precision, quality materials, and so on all affect Na blanking. However, we must find out which plays a decisive role in the quality of the blanking factor. Gap is a. Section 1 on the quality of blanking Comparison of straight, smooth, and no burr. In this case, the quality of parts that is a good cross section. When the gap is too hours of up and down the crack does not coincide with each other. . . . When the gap is too large cracks do not overlap. . . . (See 2-11) If the gap uneven distribution of local spikes. . . Uneven wear, increased, so clearance is not only to use reasonable and die on the manufacture and adjustment of space even when the guarantee. 2. Gap on the Dimensional Accuracy Blanking Stamping dimensional accuracy refers to the actual size and nominal size of the margin, the difference is smaller the higher the precision. difference between living in two areas packet error, one blanking punch or die with the size of the deviation, one mold itself create bias. Blanking and convex, die size deviation was mainly due to: Workpiece (waste) from the concave mold release, as caused by elastic recovery. Deviation may be positive, it could be negative. Factors affecting the value of this deviation are: 1, convex, concave mold gap. Big gap. . . Tensile obvious effect, elastic recovery materials and parts to drop less than the die size, punching pieces. . Small gap. . . 2, material properties. Material properties and dimensional accuracy of packages since it will then determine the material properties of its material form in the amount of blanking. Outline of the elastic deformation of the soft small amount of elastic recovery after blanking also small, so the workpiece accuracy. Hard steel elastic recovery greater precision on the lower parts. 3, workpiece shape and size. Workpiece thickness and shape of post degree only-J also have an impact, thin elastic recovery of material punching shield large,-t pieces of low accuracy. The more complex the shape of the workpiece, die and create and adjust the gap when the more difficult to ensure uniform, so the greater the size of deviations. 4. Blade-like quality video straight to the section noon 5. Gap on the impact of blanking force The smaller the gap, blanking deformation area of the higher hydrostatic pressure, the greater the material change Kang force. Blanking force, the greater the contrary, when the gap increases, lower resistance, blanking force also decreases, but the value is not reduced (see Figure 2-14) Life on the sidelines of the impact of mold (see materials abbreviated talk) Section III to determine clearance punch and die Thus, convex and concave clearance on blanking die quality morning, punching power, tool life has a great impact, so the mold design - will select a reasonable gap to ensure Blanking section of good quality punching required is small, high-die life. But the difference of quality, precision, blanking force requirements in many aspects of cooperation were identified gap is not limited to the same - a value, but close to each other, taking into account the deviation of model county manufacturing and use of wear and tear, Therefore, production is often to select an appropriate range of reasonable space, as long as the gap falls within this range can be out of good parts, the scope of the minimum value, said minimum clearance Zmin reasonably small. Most reasonable position that the biggest gap Zmax. At least a reasonable gap Z Mi n can be with the board perpendicular to the section, without a significant glitch. In the largest gap Zmax "section can still be satisfied with the quality: just not with the board vertical. Taking into account the die wear and tear during use to increase the gap, so when the design and manufacture a new model to use the smallest reasonable space Zmin Reasonable methods to determine gap calculated with the experience to determine and French. One theory to define the law ????Theory to define the main basis for the law is to ensure that cracks coincide in order to get a good cross section. Group 1 began the process of blanking the instantaneous crack q triangles from the graph we can find space z AB c ? Type in: A, - convex molded into the depth; β - the maximum shear stress direction and the angle between the vertical; ???Can be seen from the above formula, gap z and the material thickness t, the relative cut into the depth h. / T and the crack orientation day. Relevant, but to another with the material properties and β is related to the more rigid material, h. / T smaller. Therefore, we can see from the style, the main factors affecting the value gap is the material properties and thickness. The more rigid material more thick, the necessary and reasonable value of the larger gap. Table 1-3 for the popular press materials, h. / T and β approximation. A variety of materials h. / T and β value is still no accurate determination of value, and. Production is not convenient to use this method, so widely used empirical formula with the graph method. Second, the experience to determine methods Experience to determine the nature of law is based on the material and thickness, press-type to determine ? The formula: K-factor related with the material properties.?t - thickness of material. Soft materials such as 08, l0, brass, copper Z = (0.08-0.1) t In hardwood Section: A3, A 4,20,25. Z = (0.1-0.I 2) t Hard materials such as A5, 50 ... ... and so Z = (0.1-0.14) t Lower limit of thin materials which take. Third, the chart method In addition, you can directly determine the space look-up table values (such as teaching materials 2-3,2-4,2-5 table) Table 2-5 is the former Ministry of Machinery Industry, "blanking clearance," Technical Guidance Document (JB/z271-86 ) recommended clearance value. Over the past China's general information on using Soviet gap value, from the use of the experience, the gap value is generally small. One reason for this is the classification space is not used according to the characteristics of production, the other is only as the main basis for precision stamping parts, without considering the King and the chess section with a life of quality and other important factors, so many problems exist in production. For example: Wear + blanking force. . . Therefore, in practice, in addition to special requirements of the workpiece outside the vertical section, as far as possible large gap. In addition, my experience in practice should: (1) z-punching to take the value of bigger than expected drop. (2) red holes get bigger when the z value, to prevent broken punch. (3) Carbide Die z value should be 30% larger than the steel. (4)J die orifice is cone-shaped than straight smaller z value. (5) high-speed stamping dies easily when the heat, f value should get bigger. (6) when the punch and die wall thin. To prevent cracking up, should be enlarged punching z. IV Size Calculation of Cutting Edge ?Die edge dimensions and tolerances directly affect the dimensional accuracy Blanking, also is sufficient to guarantee a reasonable gap. Therefore, the correct calculation of the mold edge mold design dimensions and tolerances are small - the work of great importance. ????Dimensions and tolerances in calculating the cutting edge should follow the following principles: ????1. Taking into account the drop size depends on the materials and parts die size, while punching pieces depends on the size of the punch dimensions of the blanking die design should be to die as the base is difficult to stay in the punch on the gap; Design Punching model should be based on the punch as the base, orange on the gap left in the concave. (There is a taper section, and the big end blanking parts die size = size, empty pieces of red punch small end size = size) ????2. Taking into account the wear and tear will foot a larger die, the punch size decreases, in order to ensure the life of mold, the basic blanking die size should be taken close to or equal to the minimum limit of size of the workpiece; Piercing Punch basic dimensions shall be taken as close to the or equal to the maximum limit of size of workpiece, using the smallest reasonable gap value. ????3. Sampling edge of manufacturing tolerances, the workpiece should be to ensure the accuracy and timeliness based clearance requirements. At the same time easy to mold manufacturing tolerance is too large, then out of the parts may be disqualified, or one can guarantee a reasonable gap; too small. And to die is difficult to mold manufacturing costs. Accuracy and precision blanking dies relationship table Special Note: If the size of the workpiece is not marked tolerance. I T14 without tolerances according to class to deal with, and die according to I D 11 manufacturing (non-graphic parts). Or by I T 6-7 class manufacturing (for round parts). Mold processing method according to the different calculation methods are divided into two kinds of edge 1. Separate punch and die machining ????Separate processing: refers to the punch and die are processed separately by the respective drawings, mold the size of the gap processed by guarantee. Therefore, to calculate and mark out the punch and die dimensions and tolerances. This method is suitable for round or shape of a simple piece. ????(1) Blanking Die Blanking piece size based degree d, according to the above principles, first determine the small scale and then reduce the die size in order to ensure a reasonable punch clearance. Knife-edge part of the incidence graph of the size shown. Edge blanking die size is calculated as follows: ? (2) The punching die set punching size of d. (Standard tolerance) calculated according to the principles of the punch first determine the size. Further increasing the die size in order to ensure a reasonable minimum edge clearance associated with some of the dimensions in Figure 2-13 (b) below. Red edge aperture size is calculated as follows: ? Symbol meaning: X-tolerance zone offset factor, the purpose is to avoid all bias limit most blanking size (other omitted) ????Its value and accuracy of the workpiece. Tolerance band offset coefficient of 2-7 x to be investigated, or obtained by the following relations ???Workpiece accuracy of IT10 above: x = 1 ???Workpiece accuracy of IT11 ~ 13: x = 1.75 ??? Fine piece head IT14: x = 0.5 In order to ensure a reasonable space, mold manufacturing tolerances must meet the following conditions Convex, concave mold separate processing advantages are: convex, concave mold with interchangeable, easy to mold batch processing. ?? Convex, concave mold separate processing disadvantage: in order to ensure a reasonable gap. Require higher levels of mold manufacturing tolerances, mold making more difficult. (Based on the use of examples to explain -6,2-7 table) ? 2. Punch and die with the processing ???For complex shapes or thin material workpiece. In order to facilitate mold, should be used with the process. This method is first processed basis documents (when blanking die, punch when the punch), and then base the actual size of the Huai items to do with the other documents (when blanking punch, punch when punch), and then base the actual size of the Huai items to do with the other documents (when blanking punch, punch die when), in another space on the revised smallest reasonable value. Therefore, when used with the process, simply reference documents marked size and tolerance, another mark only basic dimensions. And marked "punch-foot small scale only by the actual preparation of the die to ensure the single gap" (blanking time); or "die size of the actual size of the preparation by the punch to ensure the side gap.." (When punching ). With the process, the base parts of the manufacturing tolerance 6f (or long) is no longer limited by the gap value, or even appropriate to enlarge manufacturing tolerances, so relatively easy to manufacture molds. Most factories have recently used this combined approach. Benchmark parts manufacturing tolerances generally preferable to A / 4 For some the shape of complex stamping parts. For each part of the size of the different nature of the wear law is different, it must be a specific analysis. Calculated separately. Figure 2-20a for the blanking parts and die size ,2-20b for the punching pieces and punch size, in these two diagrams: A class size is worn larger size, such size should be charged formula feed die size (2 ? 2) calculation, B Class size is worn by people of such small size scale should be punching punch size formula (2-4) calculation; C Class size is worn the same size, of such size, the size of the workpiece in the middle of the basic dimensions as the mold, and then standard deviation can be symmetrical, the specific formula as follows: V blanking force Cutting edge technology, including separation of materials needed for punching power and discharge power, pushing pieces of power and top pieces of power. After blanking. Washed down the workpiece (or waste) as elastic recovery and expansion will be within the infarct in the die hole. Similarly, the scrap piece〕 〔or out of the hole on the elastic contraction because of tight coupling on the punch. ? Called the discharge power;? Named top material (pieces) force;? Called push material (pieces of) force. The purpose of calculating power stamping process is it? Reasonable choice is to press tonnage. (Of course choose not to consider the tonnage presses, as well as tables, press structure... S