Stamping and flanging device for automobile parts

Abstract

The utility model discloses an automobile part stamping and flanging device which comprises an upper die base, a lower die base and a driving mechanism arranged between the upper die base and the lower die base, a detachable male die assembly is arranged at the bottom of the upper die base, a female die assembly is correspondingly arranged at the top of the lower die base, and the female die assembly comprises a base and a movable material pressing ring. The surface of the base is provided with an annular limiting groove and a stepped guide structure distributed around the limiting groove. The flanging forming design that the female die assembly and the male die assembly are combined is adopted, so that the to-be-machined part can obtain uniform pressure distribution in the stamping process, and the problem of uneven forming possibly occurring in a traditional technology is solved.

Description

Technical Field

[0001] This utility model relates to the field of automotive parts processing technology, specifically to an automotive parts stamping and flanging device. Background Technology

[0002] In modern automobile manufacturing, stamping technology, as a highly efficient and precise processing method, is widely used in the mass production of automotive parts. With the rapid development of the automotive industry, the requirements for the production precision, process efficiency, and automation level of automotive parts are constantly increasing. Against this backdrop, developing a highly efficient, accurate, and reliable stamping and flanging device is particularly important.

[0003] Traditional stamping and flanging processes typically face several problems, including inconvenient die replacement, uneven pressure distribution, and insufficient forming accuracy. These issues not only affect production efficiency but also reduce the quality of parts. Flanging devices based on internal molds often have poor adaptability and cannot meet the processing requirements of parts with various shapes. Furthermore, if the mold material used during production has insufficient wear resistance, it can easily lead to accelerated mold wear, further impacting production efficiency and product quality. Utility Model Content

[0004] In order to overcome the shortcomings of existing technical solutions, this utility model provides a stamping and flanging device for automotive parts, which can effectively solve the problems mentioned in the background art.

[0005] The technical solution adopted by this utility model to solve its technical problem is:

[0006] A stamping and flanging device for automotive parts includes an upper die base, a lower die base, and a drive mechanism disposed between the two. The bottom of the upper die base is provided with a detachable punch assembly, and the top of the lower die base is correspondingly provided with a die assembly. The die assembly includes a base and a movable pressure ring. The surface of the base is provided with an annular limiting groove and a stepped guide structure distributed around the limiting groove. The movable pressure ring is nested in the limiting groove and slides in cooperation with the stepped guide structure. The top of the movable pressure ring is also provided with a contoured curved surface that matches the contour of the part to be processed.

[0007] The bottom of the punch assembly is provided with a flanging forming surface that is complementary to the contoured curved surface, and the edge of the flanging forming surface extends into a wedge-shaped stamping cutting edge.

[0008] The driving mechanism includes two sets of hydraulic drive modules symmetrically distributed on both sides of the base, an adjustable pressure plate, and several ball joints. Each hydraulic drive module is connected to the adjustable pressure plate through a ball joint. The inner side of the adjustable pressure plate is provided with an adaptive floating block, and the surface of the adaptive floating block is covered with a wear-resistant elastic layer.

[0009] As a further description of the above technical solution, the stepped guide structure includes, from the inside out, a first-level guide, a second-level guide, and a third-level guide.

[0010] The first-stage guide consists of four cylindrical guide posts mounted on the base, and each cylindrical guide post has a tapered guide head at its top.

[0011] The second-stage guide includes a rectangular guide groove disposed at the bottom of the movable pressure ring, and a polymer wear-resistant bushing is embedded in the inner wall of the rectangular guide groove;

[0012] The third-level guide includes a T-shaped guide rail and a sliding fit structure located at the edge of the base, and the bottom of the movable pressure ring is provided with a slide rail connected to the sliding fit structure.

[0013] As a further description of the above technical solution, the cylindrical guide post and the conical guide head adopt a split structure and are connected by threads, and the surface of the cylindrical guide post is provided with a spiral lubricating grease groove.

[0014] As a further description of the above technical solution, the adaptive floating block is composed of several independent honeycomb units, each of which is embedded with a pressure sensor and a miniature spring, and the bottom of the honeycomb unit is connected to the pressure plate.

[0015] As a further description of the above technical solution, a quick-change mechanism is also provided between the punch assembly and the upper die base. The quick-change mechanism includes a positioning pin disposed at the bottom of the upper die base, hydraulic locking modules distributed on both sides of the positioning pin, a radially retractable locking claw, a tapered hole disposed at the top of the punch assembly, and a locking groove.

[0016] As a further description of the above technical solution, the lower mold base is provided with an air cushion buffer system. The air cushion buffer system includes a ring-shaped nitrogen spring group, a pressure equalization chamber set at the bottom of the base, and an air passage pipe connecting each nitrogen spring. The middle section of the air passage pipe is provided with a damping adjustment valve.

[0017] As a further description of the above technical solution, the flange forming surface and the stamping cutting edge form an angle of 5°-8°, the surface of the stamping cutting edge is coated with a titanium aluminum nitride composite coating, and the end of the stamping cutting edge is provided with a micro-serration structure of 0.2-0.5mm.

[0018] As a further description of the above technical solution, the wear-resistant elastic layer is a polyurethane-based composite material, and the surface of the wear-resistant elastic layer is provided with equally spaced hemispherical protrusions, the height of which is gradually decreasing along the pressing direction.

[0019] Compared with the prior art, the beneficial effects of this utility model are:

[0020] The present invention relates to a stamping and flanging device for automotive parts, which has at least one of the following beneficial effects during use:

[0021] The flanging design, combining a concave die assembly and a convex die assembly, ensures uniform pressure distribution on the workpiece during stamping, avoiding uneven forming problems that may occur in traditional processes. This feature directly improves the processing quality and yield rate of the parts. The yielding function design in the device, such as the combination of adaptive floating blocks and a wear-resistant elastic layer, effectively absorbs impact forces, reduces die wear and damage, and extends die life. Furthermore, the hemispherical protrusions on the wear-resistant elastic layer disperse impact loads, further reducing friction and heat generation, thereby improving overall work efficiency. Equipped with an air cushion buffer system, it effectively reduces impact damage to the die and workpiece, improving equipment reliability and safety. Simultaneously, the application of a quick-change mechanism significantly shortens die changeover time, improves production efficiency, and meets the demands of modern production for rapid response. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of a stamping and flanging device for automotive parts according to the present invention;

[0023] Figure 2 This is a side view of the stamping and flanging device for automotive parts according to the present invention.

[0024] Figure 3 This is a perspective structural diagram of a stamping and flanging device for automotive parts according to the present invention.

[0025] Numbering on the map:

[0026] 1. Upper die base; 101. Punch assembly; 102. Flanging forming surface; 103. Stamping cutting edge; 104. Adaptive floating block; 105. Honeycomb unit; 106. Quick change mechanism; 107. Positioning pin; 108. Hydraulic locking module; 109. Locking claw; 110. Miniature spring; 111. Pressure sensor; 112. Adjustable pressure plate; 2. Lower die base; 201. Die assembly; 202. 203. Stepped guide structure; 204. Air cushion buffer system; 205. Movable pressure ring; 206. Base; 207. Slide rail; 208. Limiting groove; 209. Contour surface; 210. Rectangular guide groove; 211. T-shaped guide rail; 212. Air pipeline; 213. Nitrogen spring; 214. Conical guide head; 301. Cylindrical guide post; 3. Drive mechanism; 301. Hydraulic drive module; 302. Ball joint. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] like Figure 1-3 As shown, this utility model provides a stamping and flanging device for automotive parts, including an upper die base 1, a lower die base 2, and a driving mechanism 3 disposed between the two. The bottom of the upper die base 1 is provided with a detachable punch assembly 101, and the top of the lower die base 2 is correspondingly provided with a die assembly 201. The die assembly 201 includes a base 205 and a movable pressure ring 204. The surface of the base 205 is provided with an annular limiting groove 207 and a stepped guide structure 202 distributed around the limiting groove 207. The movable pressure ring 204 is nested in the limiting groove 207 and slides in cooperation with the stepped guide structure 202. The top of the movable pressure ring 204 is also provided with a contoured curved surface 208 that matches the contour of the part to be processed.

[0029] The stamping and flanging device in this embodiment achieves high-precision flanging of automotive parts through the coordinated action of the stepped guide structure 202, the contoured surface 208, and the adaptive pressure mechanism. Precision flanging is achieved through a three-stage linkage pressure transmission system. The hydraulic drive module 301 (500kN) transmits vertical pressure to the adjustable pressure plate 112 via the ball joint 302. The honeycomb unit 105, adapted to the floating block, automatically adjusts the contact pressure distribution according to the part shape. The movable pressure ring 204 is precisely positioned (accuracy ±0.02mm) under the constraint of the stepped guide structure. The wedge-shaped stamping cutting edge 103 and the contoured surface 208 form a progressive bending angle.

[0030] The bottom of the punch assembly 101 is provided with a flanging forming surface 102 that is complementary to the contoured curved surface 208, and the edge of the flanging forming surface 102 extends into a wedge-shaped stamping cutting edge 103.

[0031] In this embodiment, during the pressing process, the bottom flanging surface 102 of the punch assembly 101 first contacts the sheet metal. Since the flanging surface 102 is completely complementary to the contoured surface 208 of the target workpiece, the sheet metal is forced to undergo plastic deformation along the preset three-dimensional contour under mechanical pressure. The contoured contact design avoids local stress concentration and ensures uniform material flow.

[0032] When the flanging process is 80%-90% complete, the edge-extending wedge-shaped stamping cutting edge 103 begins to engage. The wedge structure decomposes the vertical stamping force into a composite force of horizontal shearing and vertical extrusion, with the cutting edge entering the material at an angle of approximately 15-30°. This progressive entry method, compared to vertical punching, can reduce the instantaneous impact load by approximately 40%, while simultaneously improving the cross-sectional quality through shearing action. It is suitable for complex workpieces such as automotive body panels that require simultaneous flanging and hole forming.

[0033] At the end of the stamping stroke, the flanging forming surface 102 and the die cavity are completely closed, performing final shaping of the formed curved surface. The wedge cutting edge then completes material separation, and its tilt angle design guides the scrap to slide off naturally, avoiding die jamming.

[0034] The drive mechanism 3 includes two sets of hydraulic drive modules 301 symmetrically distributed on both sides of the base 205, an adjustable pressure plate 112, and several ball joints 302. Each hydraulic drive module 301 is connected to the adjustable pressure plate 112 through the ball joint 302. The inner side of the adjustable pressure plate 112 is provided with an adaptive floating block 104, and the surface of the adaptive floating block 104 is covered with a wear-resistant elastic layer.

[0035] In this embodiment, two sets of hydraulic drive modules 301 are arranged in a mirror-symmetrical manner on both sides of the base 205, and synchronous pressurization is achieved through a closed-loop servo system (synchronization accuracy ≤0.1mm). When the system starts, the hydraulic cylinder outputs axial thrust at a pressure of 15-25MPa, which is transmitted to the adjustable pressure plate 112 through the ball joint 302. The universal adjustment capability of the ball joint structure (angle compensation ±5°) can eliminate the risk of mechanism jamming caused by workpiece positioning deviation or mold wear.

[0036] The symmetrical hydraulic drive system, combined with closed-loop feedback, maintains the flatness of the pressure plate at 0.02 mm / m. 2 This represents a 60% improvement over traditional single-point drive methods. The adaptive floating block 104 is compatible with curved workpieces ranging from R5 to R2000mm, and through independent control of the pneumatic unit, it achieves seamless switching from a planar to a hyperbolic structure.

[0037] Furthermore, the stepped guide structure 202 includes, from the inside out, a first-level guide, a second-level guide, and a third-level guide;

[0038] The first-stage guide consists of four cylindrical guide posts 314 mounted on the base 205, and each cylindrical guide post 314 has a tapered guide head 213 at its top.

[0039] The second-stage guide includes a rectangular guide groove 209 disposed at the bottom of the movable pressure ring 204, and a polymer wear-resistant bushing is embedded in the inner wall of the rectangular guide groove 209;

[0040] The third-level guide includes a T-shaped guide rail 210 and a sliding fit structure located on the edge of the base 205, and the bottom of the movable pressure ring 204 is provided with a slide rail 206 that connects to the sliding fit structure.

[0041] The tapered guide head 213 (15° cone angle) achieves a tolerance compensation of ±5mm through inclined surface contact during initial pressing. The tapered surface forms a surface contact with the guide hole of the movable pressure ring 204, increasing the contact area by 30% compared to the traditional cylindrical guide, thus controlling the initial positioning accuracy within ±0.2mm. After the movable pressure ring 204 moves down 50mm, its bottom rectangular guide groove 209 (dimensional tolerance H7 / g6) enters a mating state with the cylindrical guide post 314. The polytetrafluoroethylene-bronze composite bushing (8mm thick) embedded in the guide groove operates with a gap of 0.05-0.1mm, utilizing the self-lubricating properties of the polymer material to reduce the sliding friction coefficient to 0.08 (1 / 5 of that of traditional metal guides). When the pressure ring travels to 80% of its total travel, the bottom slide rail 206 (hardened treatment HRC58-62) forms a surface contact with the base 205 T-type guide rail 210 (straightness 0.01mm / m). The T-shaped structure, through double 45° guide ramps, compresses the lateral clearance to 0.005-0.01mm, achieving a repeatability positioning accuracy of 0.005mm at the end of the entire stroke.

[0042] Furthermore, the cylindrical guide post 314 and the tapered guide head 213 adopt a split structure and are connected by threads. The surface of the cylindrical guide post 314 is provided with spiral lubricating grease grooves. The cylindrical guide post 314 (material GCr15, surface hardening hardness HRC58-62) and the tapered guide head 213 (material cemented carbide YG15) are connected by a precision trapezoidal thread (Tr40×6, fitting accuracy 6H / 6g). During installation, a preload control technology (torque value 120±5N·m) is used to ensure that the contact pressure of the connection surface reaches 25-30MPa. The split structure allows the guide post and guide head to be machined separately. The cylindricity of the cylindrical guide post 314 is controlled within 0.003mm, and the cone angle machining error of the tapered guide head 213 is ≤0.02°. After assembly, the overall coaxiality reaches 0.005mm / m.

[0043] When the guide post reciprocates: During the upward movement: the spiral groove pumps the grease (NLGI 2# lithium-based grease) in the bottom oil reservoir upward to form a continuous oil film; During the downward movement: the scraping action of the groove edge promotes the grease to spread evenly, and the oil film thickness is maintained at 5-8μm; the hydrodynamic pressure effect generated by the spiral structure makes the lubricant pressure in the contact area reach 0.8-1.2MPa, effectively isolating metal contact.

[0044] Furthermore, the adaptive floating block 104 is composed of several independent honeycomb units 105, each of which is embedded with a pressure sensor 111 and a miniature spring 110, and the bottom of the honeycomb unit 105 is connected to the pressure plate.

[0045] When the pressure plate contacts the workpiece, each honeycomb unit 105 is compressed independently. The contact force is monitored in real time by the pressure sensor 111. The viscosity of the magnetorheological fluid is dynamically adjusted according to the current control (0-1A), forming a variable damping system of 0.01-5 N·s / mm. The contact pressure non-uniformity is reduced from ±30% in the traditional structure to ±3%. The magnetorheological damper completes the buffering of a 10kN impact load within 15ms.

[0046] Furthermore, a quick-change mechanism 106 is provided between the punch assembly 101 and the upper die base 1. The quick-change mechanism 106 includes a positioning pin 107 disposed at the bottom of the upper die base 1, hydraulic locking modules 108 distributed on both sides of the positioning pin 107, a radially retractable locking claw 109, a tapered hole and a locking groove disposed at the top of the punch assembly 101.

[0047] The top of the punch assembly 101 is machined with a 1:20 taper positioning conical hole (surface roughness Ra0.4μm), which mates with the carbide positioning pin 107 (diameter Φ50±0.002mm) at the bottom of the upper die holder 1. When the punch assembly 101 is hoisted and lowered, the conical hole and the positioning pin 107 automatically align, with the clearance controlled within 0.003-0.005mm, ensuring a repeatability positioning accuracy of ±0.005mm.

[0048] The hydraulic locking modules 108 on both sides (working pressure 25MPa) push the eight radial locking claws 109 (material 20CrMnTi, carburized and quenched HRC60-62) to operate synchronously.

[0049] Locking stage: The hydraulic cylinder stroke is 30mm, and the wedge block (angle 15°) at the end of the locking claw 109 is embedded in the annular locking groove (groove depth 8mm, tolerance H7 / h6) on the top of the punch, generating axial preload (single claw locking force 12kN, total locking force 96kN).

[0050] Unlocking phase: Reverse hydraulic oil pushes the locking claw 109 to retract, and the built-in disc spring assembly provides a 3kN separation force to ensure rapid disengagement;

[0051] The hydraulic system uses an accumulator to maintain pressure, with pressure fluctuation ≤ ±0.5MPa and locking state maintenance time ≥ 72 hours.

[0052] Furthermore, the lower mold base 2 is equipped with an air cushion buffer system 203. The air cushion buffer system 203 includes a group of nitrogen springs 212 arranged in a ring, a pressure equalization chamber set at the bottom of the base 205, and an air passage pipe 211 connecting each nitrogen spring 212. The middle section of the air passage pipe 211 is equipped with a damping adjustment valve.

[0053] Twelve sets of nitrogen springs 212 arranged in a ring (each cylinder has a volume of 0.8L and a pre-charge nitrogen pressure of 12MPa±0.5MPa) are connected in series through a gas pipe 211 (inner diameter Φ16mm). When the upper mold is pressed down:

[0054] Initial stage (stroke 0-30mm): The spring assembly compresses synchronously, and the nitrogen pressure rises linearly to 18MPa, providing a gradient stiffness of 0.5-5kN / mm;

[0055] Equalization stage: The pressure equalization chamber (8L volume, hard chrome plated on the inner wall) balances the air pressure difference in the region through 8 Φ6mm pressure equalization holes, and the pressure fluctuation is controlled within ±0.3MPa;

[0056] Damping adjustment: The PID controller adjusts the damping valve opening (0-100%) in real time according to the displacement sensor (sampling rate 500Hz) to stabilize the airflow speed at 15-25m / s.

[0057] The damping valve uses a porous titanium alloy core (pore diameter Φ0.5-2mm gradient distribution) to attenuate 90% of the 200Hz vibration energy within 5ms. The built-in temperature compensation module (PT100 sensor ±0.1℃ accuracy) automatically corrects the gas PVT characteristics to ensure that the stiffness deviation is <3% under the operating conditions of -20℃~150℃. When a single cylinder pressure loss is detected to be >15%, the backup air circuit is automatically bypassed to maintain the system pressure ≥10MPa.

[0058] Furthermore, the flanged forming surface 102 and the stamping cutting edge 103 form an angle of 5°-8°, the surface of the stamping cutting edge 103 is coated with a titanium aluminum nitride composite coating, and the end of the stamping cutting edge 103 is provided with a micro-serration structure of 0.2-0.5mm.

[0059] The flange angle design reduces the springback from 0.15-0.3mm to 0.03-0.05mm, and the micro-serrated structure improves the surface roughness of the punched surface from Ra 1.6μm to Ra 0.4μm.

[0060] Furthermore, the wear-resistant elastic layer is a polyurethane-based composite material, and the surface of the wear-resistant elastic layer is provided with equally spaced hemispherical protrusions, the height of which decreases gradually along the pressing direction.

[0061] Polyurethane-based composite materials possess excellent wear resistance, elasticity, and flexibility, effectively absorbing impact and vibration, reducing damage to dies during stamping, and extending their service life. The evenly spaced hemispherical protrusions on the wear-resistant elastic layer surface are designed primarily to increase the contact area with the workpiece, enhance friction, and thus improve the pressing effect during the forming process. The suspended hemispherical protrusions effectively disperse impact force, achieving uniform pressure distribution and preventing excessive localized wear on the workpiece surface.

[0062] The height of the hemispherical protrusion decreases gradually along the blanking direction, resulting in a gradual reduction in contact pressure during stamping and thus avoiding stress concentration caused by sudden contact. This helps reduce impact and damage to the mold and workpiece, and improves the quality and consistency of parts processing.

[0063] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. An automobile part stamping flanging device, comprising an upper die holder, a lower die holder and a driving mechanism arranged between the two, the bottom of the upper die holder is provided with a detachable punch assembly, and the top of the lower die holder is provided with a corresponding concave die assembly, characterized in that: The die assembly includes a base and a movable pressure ring. The base surface is provided with an annular limiting groove and a stepped guide structure distributed around the limiting groove. The movable pressure ring is nested in the limiting groove and slides in cooperation with the stepped guide structure. The top of the movable pressure ring is also provided with a contoured curved surface that matches the contour of the part to be processed. The bottom of the punch assembly is provided with a flanging forming surface that is complementary to the contoured curved surface, and the edge of the flanging forming surface extends into a wedge-shaped stamping cutting edge. The driving mechanism includes two sets of hydraulic drive modules symmetrically distributed on both sides of the base, an adjustable pressure plate, and several ball joints. Each hydraulic drive module is connected to the adjustable pressure plate through a ball joint. The inner side of the adjustable pressure plate is provided with an adaptive floating block, and the surface of the adaptive floating block is covered with a wear-resistant elastic layer.

2. A press flanging device for automobile parts as claimed in claim 1 wherein: The stepped guide structure includes, from the inside out, a first-level guide, a second-level guide, and a third-level guide; The first-stage guide consists of four cylindrical guide posts mounted on the base, and each cylindrical guide post has a tapered guide head at its top. The second-stage guide includes a rectangular guide groove disposed at the bottom of the movable pressure ring, and a polymer wear-resistant bushing is embedded in the inner wall of the rectangular guide groove; The third-level guide includes a T-shaped guide rail and a sliding fit structure located at the edge of the base, and the bottom of the movable pressure ring is provided with a slide rail connected to the sliding fit structure.

3. A press flanger for automobile parts as claimed in claim 2 wherein: The cylindrical guide post and the tapered guide head are separate structures connected by threads, and the surface of the cylindrical guide post is provided with a spiral lubricating grease groove.

4. The press flanger for an automotive part as set forth in claim 1, wherein: The adaptive floating block is composed of several independent honeycomb units, each of which is embedded with a pressure sensor and a miniature spring. The bottom of the honeycomb unit is connected to the pressure plate.

5. The press flanger for an automotive part as set forth in claim 1, wherein: A quick-change mechanism is also provided between the punch assembly and the upper die base. The quick-change mechanism includes a positioning pin at the bottom of the upper die base, hydraulic locking modules distributed on both sides of the positioning pin, a radially retractable locking claw, a tapered hole and a locking groove at the top of the punch assembly.

6. A press flanger for automobile parts as claimed in claim 1 wherein: The lower mold base is equipped with an air cushion buffer system, which includes a ring-shaped nitrogen spring assembly, a pressure equalization chamber located at the bottom of the base, and an air passage connecting each nitrogen spring. The middle section of the air passage is equipped with a damping adjustment valve.

7. The press flanger for an automotive part as set forth in claim 1, further comprising: The flanged forming surface and the stamping cutting edge form an angle of 5°-8°. The surface of the stamping cutting edge is coated with a titanium aluminide composite coating. The end of the stamping cutting edge is provided with a micro-serration structure of 0.2-0.5mm.

8. The press flanger for an automotive part as set forth in claim 1, further comprising: The wear-resistant elastic layer is a polyurethane-based composite material. The surface of the wear-resistant elastic layer is provided with equally spaced hemispherical protrusions, and the height of the hemispherical protrusions decreases gradually along the pressing direction.

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