Springback compensation auxiliary forming device for rubber bag mold of plate bending type part
By designing a rubber bladder mold rebound compensation auxiliary forming device including a detachable depressor base, rebound compensation mold model surface and movable sinking booster block, the problems of excessive rebound size, poor manufacturing accuracy and excessive workpiece quantity during hydraulic forming of plate bend parts are solved, and high-precision and low-cost part forming are achieved.
Patent Information
- Application Number
- CN202421090088.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-17
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-05-17
AI Technical Summary
During the hydraulic forming process of plate bend parts, there are problems such as excessive bending size, poor sinking manufacturing accuracy, and excessive workload quantity.
A rubber bladder mold rebound compensation auxiliary forming device is designed, including a detachable lower mold matrix and rebound compensation mold mold surface, combined with a moving downward booster block and polyurethane material, rebound compensation is performed through simulation technology and typical parts rebound database.
It effectively reduces the number of mold tools, improves the manufacturing accuracy of parts, reduces production costs, and reduces the scrap rate of parts.
Smart Images
Figure CN222985426U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of hydraulic equipment tooling, and relates to a springback compensation auxiliary forming device for a rubber bladder mold of sheet bending parts. Background Technique
[0002] The hydraulic forming process method uses a rubber pad or a hydraulic rubber bladder as a general elastic female die (or male die), so that the metal sheet is formed by pressing according to a rigid male die (or female die). It has the advantages of high working efficiency, low cost, high safety performance, etc. The formed parts mainly include frames, ribs, etc. There are relief holes, positioning holes and reinforcing ribs on the webs of the parts. There are depressions in the flanging or web parts of some parts. The purpose of the depressions is to ensure the close fit between parts. In aircraft manufacturing, sheet bending parts mainly refer to parts such as connecting pieces, angle pieces, and frame edges. The part forms include straight flanging, convex curve flanging, concave curve flanging, compound flanging, multiple flanging, etc. After the parts are hydraulically formed, springback always occurs, making the parts unable to fit completely with the die blank, and manual knocking and repairing are required, resulting in poor surface quality of the parts. There is always a phenomenon that the depression position of the part does not fit tightly with the die blank. At the same time, once the part structure form changes, a set of pressing tooling needs to be remanufactured for forming. In short, in the process of rubber bladder hydraulic forming of sheet bending parts, the springback dimension of the flanging exceeds the tolerance, the manufacturing accuracy of the depression is poor, and the number of toolings is too large are common manufacturing problems. Content of the Utility Model
[0003] Purpose to be solved by the utility model: The purpose of the utility model is to solve the technical problems such as the springback dimension of the flanging exceeding the tolerance, the poor manufacturing accuracy of the depression, and the excessive number of toolings existing in the prior art.
[0004] Technical solution of the utility model:
[0005] A springback compensation auxiliary forming device for a rubber bladder mold of sheet bending parts includes a sheet bending part, and also includes an upper die and a lower die. The lower die includes a lower die base body and a springback compensation die surface. The springback compensation die surface is installed on the side of the lower die base body. Depressions located on the same straight line are provided on the lower die base body and the springback compensation die surface. The upper die is arranged on the lower die base body and the springback compensation die surface. There is a springback angle between the outer side surface of the springback compensation die surface and the inner side surface of the theoretical flanging of the sheet bending part. The sheet bending part is arranged between the upper die and the lower die. A movable depression pressure increasing block is arranged on the sheet bending part, and the movable depression pressure increasing block completely covers the depressions on the lower die base body and the springback compensation die surface.
[0006] Further, the springback compensation die surface is made of polyurethane material, and the lower die base body and the upper die are made of material ZS-340.
[0007] Further, the movable depression boosting block is a thin rubber pad.
[0008] Further, the springback compensation die surface is detachably installed on the side of the lower die base.
[0009] Further, the thickness of the movable depression boosting block is 2 - 5 mm.
[0010] Further, positioning holes corresponding to each other in position are provided on the lower die base and the upper die, and the lower die base and the upper die are positioned and connected by pins.
[0011] Advantages of the present utility model:
[0012] The present utility model provides a rubber bladder die springback compensation assisted forming device for plate bending parts. The lower die of the die adopts a detachable form, and multiple die forming surfaces can be installed on one base, reducing the number of die toolings and the production cost; a movable depression boosting block is designed to increase the forming pressure at the depression position of the part and improve the manufacturing precision of the part; the die surface is made of polyurethane material, and by using the springback database of typical parts, appropriate over-springback compensation is carried out on the die surface to achieve a high manufacturing precision of the part. At the same time, the polyurethane material has a strong adaptability to the deformation of the main structure, can prevent the part from cracking during forming, and reduce the scrap rate of the part. Description of the drawings
[0013] Figure 1 is a typical plate bending part;
[0014] Figure 2 is a hydraulic forming tooling for typical plate bending parts;
[0015] Figure 3 is a top view of the rubber bladder die springback compensation assisted forming device for plate bending parts of the present utility model;
[0016] Figure 4 is a front view of the rubber bladder die springback compensation assisted forming device for plate bending parts of the present utility model;
[0017] Wherein: 1 - lower die base, 2 - springback compensation die surface, 3 - plate bending part, 4 - movable depression boosting block, 5 - lower die, 6 - upper die;
[0018] Figure 5 is an installation schematic diagram of the movable depression boosting block;
[0019] Figure 6 is a springback compensation schematic diagram of typical plate bending parts. Detailed implementation manners
[0020] The following further introduces the present utility model with reference to the drawings:
[0021] The first embodiment of the present utility model is:
[0022] A proposed plate bending part rubber bag mold rebound compensation auxiliary forming device is used for the hydraulic forming of aircraft plate bending parts 3, including the plate bending parts 3, and also including an upper mold 5 and a lower mold 6, the lower mold 5 includes a lower mold base 1 and a rebound compensation mold surface 2, the rebound compensation mold surface 2 is installed on the side of the lower mold base 1, the lower mold base 1 and the rebound compensation mold surface 2 are provided with a depression located on the same straight line, which is used to process the sunken area of the plate bending parts 3, the upper mold 6 is arranged on the lower mold base 1 and the top surface of the rebound compensation mold surface 2, the outer side surface of the rebound compensation mold surface 2 is consistent with the theoretical bending area of the plate bending parts There is a springback angle between the inner side surfaces of the edge, and the angle value of the springback angle is calculated based on a typical part springback database. The springback angle is used to compensate for the springback of the plate-bending parts 3 during the hydraulic forming process, so that the bending angle of the plate-bending parts 3 during hydraulic forming is smaller than the theoretical bending angle of the parts. The plate-bending parts 3 are arranged between the upper die 5 and the lower die 6, and an active sinking boosting block 4 is arranged on the plate-bending parts 3. The active sinking boosting block 4 completely covers the sinking on the lower die base 1 and the springback compensation mold surface 2. The active sinking boosting block 4 is designed to increase the forming pressure at the sinking position of the plate-bending parts 3 during the hydraulic forming process, thereby improving the manufacturing accuracy of the parts.
[0023] In this embodiment, the movable subsidence boosting block 4 is made of a thinner rubber material, the movable polyurethane rebound compensation mold surface 2 and the lower mold base 1 are detachably connected, and the lower mold base 1 and the upper mold 6 are made of ordinary mold manufacturing material ZS-340.
[0024] In this embodiment, the lower mold 5 of the mold is connected to the plate-bending parts 3 by pin positioning, and the movable sunken boosting block 4 is placed above the sunken position of the plate-bending parts 3, and must completely cover the sunken position of the plate-bending parts 3. The upper mold 6 is placed above the movable sunken boosting block 5 and fits tightly with the lower mold.
[0025] In this embodiment, the movable polyurethane rebound compensation mold surface 2 is manufactured by CNC machining according to the part digital model, and the rebound angle of the plate bending part 3 is used to make corresponding rebound compensation for the mold surface, so that the bending angle of the plate bending part 3 during hydraulic forming is smaller than the theoretical bending angle of the part. After the pressing is completed, the bending angle of the plate bending part 3 during hydraulic forming is smaller than the theoretical bending angle of the part, and rebound occurs to obtain the part shape required by the design. Mechanical compensation by researching and polishing the mold is very time-consuming. Simulation technology is used to preview the deformation of the part and provide compensation angles, so as to obtain a typical part rebound database for guiding the design of part tooling. Since the material properties, corner radius, bending height, thickness, etc. of the part will affect the rebound value, different parts correspond to different polyurethane rebound compensation mold surfaces 2.
[0026] In the present utility model, the connection mode at the disassembly position of the detachable lower die 5 adopts the traditional mortise and tenon structure, facilitating the disassembly and assembly of the springback compensation die surface 2 and the lower die base 1.
[0027] In the present utility model, the movable sinking pressure increasing block 4 is made of rubber material with a thickness of 2 - 5 mm, and is lined between the part and the upper die 6. When the upper die 6 is pressurized, it presses the plate bending part 3 and the lower die 5 tightly.
[0028] The second embodiment of the present utility model is:
[0029] Combined with the attached drawings, a rubber bladder die device that is detachable, has a movable sinking pressure increasing block 4, and compensates for the springback of the machining surface is provided. Figure 1 is a typical plate bending part that can be formed by using this die tooling. Figure 2 is a schematic diagram of the overall installation and application of the die. Figure 3 、 Figure 4 is a schematic diagram of the rubber bladder die that is detachable, has a sinking pressure increasing block, and compensates for the springback of the machining surface. Figure 5 is a schematic diagram of the installation of the movable sinking pressure increasing block. Figure 6 is a schematic diagram of the springback compensation of a typical plate bending part. The upper die 6 of the die is manufactured according to the tooling digital model, using ZS - 340 material. The detachable lower die 5 uses polyurethane material. The springback compensation die surface 2 can be repaired and compensated according to the springback angle of the part. For example, Figure 6 The springback angle of the pressed plate bending part 3 is predicted by using simulation software. Through actual verification, the actual springback angle value of the typical part is obtained, which is used to guide the tooling design.
[0030] During actual verification, in order to quickly and accurately obtain the springback value of the part, the first die repair angle is smaller than the simulation prediction angle. By increasing the die springback compensation value in an arithmetic progression of 0.5° each time, the actual die springback compensation value is obtained, and a springback database of typical parts is established to form a process document. For example, Figure 3 As shown, the lower die base 1 is manufactured according to the tooling digital model, using ZS - 340 material, and is connected to the detachable lower die 5 with a mortise and tenon structure. For different plate bending parts, the detachable lower die 5 corresponds to the part machining surface, and the lower die base 1 remains unchanged. The movable sinking pressure increasing block 4 is installed between the part and the upper die 6 or between the part and the rubber bladder, increasing the forming pressure in the sinking area, making the part fit tightly with the lower die 5, and achieving the purpose of one - time forming of the part.
[0031] When the depression depth of the part is relatively large, a rubber bladder hydroforming tooling is designed through the 3D model of the part. The rubber bladder hydroforming tooling includes an upper die 6 and a lower die 5. The lower die 5 is designed as two parts: a fixed base and a machining surface that varies with the part. The upper and lower dies 5 are positioned by pins, and the lower die 5 and the part are also positioned by pins. The lower die base 1 and the springback compensation die surface 2 are connected and positioned by a mortise and tenon structure. The upper die 6 is made of ZS-340 material, the machining surface of the lower die 5 is made of polyurethane material, and the lower die base 1 is made of ZS-340 material. The die system is all manufactured by CNC machining according to the tooling digital model.
[0032] The movable depression pressure increasing block 4 is made of rubber, manufactured according to the size of the depression position of the lower die 5 of the die, and the thickness is preferably 2-5 mm. It is selected according to the depression depth of the part. The greater the depression depth, the thicker the movable depression pressure increasing block 4; the smaller the depression depth, the thinner the movable depression pressure increasing block 4. It is laid flat between the part and the upper die 6.
[0033] The movable polyurethane springback compensation die surface 2 is manufactured according to the part. One set of polyurethane die surfaces corresponds to one part form, and the springback compensation angle is determined according to the springback angle of the part. By using the simulation forming technology, the theoretical springback value of the part is obtained, and a typical part springback database is formed. The springback compensation angles of the pressing dies of the compensating sheets of a certain type of aircraft are all 3°. The die springback compensation angle can be equal to or slightly larger than the part springback angle because the polyurethane material has a certain elasticity. At the same time, because the polyurethane material has a strong adaptability to the deformation of the main structure, parts with a smaller fillet radius can be formed.
[0034] Example Two:
[0035] When the depression depth of the part is relatively small, a rubber bladder hydroforming tooling is designed through the 3D model of the part. At this time, the die does not require the upper die 6, and the rubber bladder hydroforming tooling only has the lower die 5. The lower die 5 is designed as two parts: a fixed base and a machining surface that varies with the part. The lower die 5 and the part are positioned by pins, and the lower die base 1 and the springback compensation die surface 2 are connected and positioned by a mortise and tenon structure. The springback compensation die surface 2 is made of polyurethane material, and the lower die base 1 is made of ZS-340 material. The die system is all manufactured by CNC machining according to the tooling digital model.
[0036] The movable depression pressure increasing block 4 is made of rubber, manufactured according to the size of the depression position of the lower die 5 of the die, and the thickness is preferably 2-3 mm. It is selected according to the depression depth of the part and laid flat above the depression position of the part to increase the forming pressure at the depression position of the part during rubber bladder hydroforming, so that the part is closely attached to the lower die.
[0037] The movable polyurethane springback compensation die surface 2 is manufactured according to the part. One set of polyurethane die surfaces corresponds to one part form, and the springback compensation angle is determined according to the part springback angle. By using the simulation forming technology, the theoretical springback value of the part is obtained, and a springback database of typical parts is formed. The springback compensation angle of the die for a certain type of airframe flange is 12°. The die springback compensation angle can be equal to or slightly larger than the part springback angle because the polyurethane material has a certain elasticity. At the same time, due to the strong adaptability of the polyurethane material to the deformation of the main structure, parts with a relatively small fillet radius can be formed.
[0038] The utility model discloses an auxiliary forming device for springback compensation of a rubber bladder die for plate bending parts. The device includes an upper die 6 of the die, a lower die base 1, a movable depression pressurizing block 4, and a movable polyurethane springback compensation die surface 2. The lower die base 1 and the movable polyurethane springback compensation die surface 2 are connected by a mortise and tenon structure, which is convenient for installation and disassembly, reduces the number of dies. The movable depression pressurizing block 4 is laid flat between the part and the upper die 6 or above the part depression position to assist the part to closely fit with the lower die 5 during hydroforming, improving the forming accuracy of the part depression position. The movable polyurethane springback compensation die surface 2 corrects the springback compensation according to the part springback angle, and the part springback angle is obtained by combining simulation prediction and actual verification. At the same time, parts with a relatively small fillet radius can be formed, reducing the rejection rate of parts due to cracking. This auxiliary forming device for die springback compensation can improve the forming accuracy of plate bending parts, reduce the investment in tooling, enable one-time forming of parts, and reduce the workload of manual shape correction.
Claims
1. A plate-bending part rubber bag mold rebound compensation auxiliary forming device, including plate-bending parts, characterized in that: It also includes an upper die and a lower die, the lower die includes a lower die base and a springback compensation die surface, the springback compensation die surface is installed on the side of the lower die base, the lower die base and the springback compensation die surface are provided with depressions located on the same straight line, the upper die is arranged on the lower die base and the springback compensation die surface, there is a springback angle between the outer side surface of the springback compensation die surface and the inner side surface of the theoretical bending edge of the plate bending parts, the plate bending parts are arranged between the upper die and the lower die, and a movable sinking boosting block is arranged on the plate bending parts, and the movable sinking boosting block completely covers the sinking on the lower die base and the springback compensation die surface.
2. The springback compensation auxiliary forming device for rubber bag mold of plate bending parts according to claim 1 is characterized in that: The springback compensation mold profile is made of polyurethane material, and the lower mold base and the upper mold are made of material ZS-340.
3. The springback compensation auxiliary forming device for rubber bag mold of plate bending parts according to claim 1 is characterized in that: The movable sinking and pressurizing block is a thin rubber pad.
4. The springback compensation auxiliary forming device for rubber bag mold of plate bending parts according to claim 1 is characterized in that: The springback compensation die profile is detachably mounted on the side of the lower die base.
5. The springback compensation auxiliary forming device for rubber bag mold of plate bending parts according to claim 2 is characterized in that: The thickness of the movable sinking and pressurizing block is 2-5 mm.
6. The springback compensation auxiliary forming device for rubber bag mold of plate bending parts according to claim 1 is characterized in that: The lower mold base and the upper mold are provided with corresponding positioning holes, and the lower mold base and the upper mold are positioned and connected by pins.