Hydraulic forming die and method for different-direction S-bent-edge partition plate type sheet metal parts

Abstract

The invention provides a hydraulic forming die and method for a different-direction S-bent-edge partition plate type sheet metal part. Flanging lightening holes are distributed in a web plate face of the partition plate type sheet metal part, the two sides of the partition plate type sheet metal part are shape-following different-direction bent edges in lap joint with a skin, the longitudinal section of the partition plate type sheet metal part is approximately in an S shape, and the partition plate type sheet metal part has the advantages of being complex in structure, multiple in turned edge and semi-closed. Based on the structural characteristics of the parts, the hydraulic forming method and the die structure of the anisotropic S-bent-edge partition plate type sheet metal parts are provided, and the using method comprises the following steps that a combined die with an elastic mechanism is manufactured according to the part structures and used for integrally forming the parts, and part unfolding materials are placed on a mold tire 2; when the movable pins 5 on the two sides of the part are used for positioning and a hydraulic machine transmits pressure downwards, the cover plate 1 and the mold 2 press the blank tightly, the elastic mechanism, namely the cylindrical spiral compression spring 6 is compressed, the mold 2 is attached to the groove of the base 3, and the bent edges on the two sides of the part are formed at a time.

Description

Technical Field

[0001] The invention relates to a sheet metal parts forming technology in the field of aircraft manufacturing, in particular to a hydraulic forming die and method for sheet metal parts such as hetero-directional S-bend partitions. Background Art

[0002] There are many frame-ribbed sheet metal parts in aviation parts. The structure of such parts is relatively complex. Usually, the belly surface is flat, with curved edges on both sides, and the outer edge is variable curvature or variable angle. There are also structures such as lightening holes or strengthening stems distributed on the belly surface of the parts. There is also a lower limit on the curved edge to ensure that the parts are assembled to fit the aircraft skin shape. There are many varieties of such parts, and rubber hydraulic forming is usually used.

[0003] Rubber forming has high production efficiency, and multiple parts can be produced on the same workbench at the same time; because the surface of the part contacts the rubber during forming, the surface quality of the part after forming is good; the rubber can replace the concave mold, thus saving the mold cost and reducing the mold manufacturing cycle. In the past, when this type of sheet metal parts such as S-bend partitions were formed by rubber, because the parts had reverse bends, two sets of tooling were generally used to form the bends separately. For parts with concave and convex curves, the concave bends are closer to the tire than the convex bends. Therefore, the first set of molds are used to form the concave bends first, and when the second set of molds are used to form the convex bends, the formed concave bends are avoided and protected. The advantage of using a combination mold is that the shape of the part can be hydraulically formed at one time, and the part can be disassembled for trimming, and the parts can be inspected based on the degree of fit and shape line.

[0004] Two sets of tooling are required for forming sheet metal parts such as heterogeneous S-bend partitions, and the convex and concave bends are formed in sequence. This has the disadvantages of a large number of tooling, high cost, long mold replacement time, high labor intensity and low production efficiency. Summary of the invention

[0005] The present application provides a hydraulic forming mold and method for sheet metal parts such as anisotropic S-bend partitions, which utilizes an elastic device—a cylindrical helical compression spring—to decompose the unidirectional power source during rubber forming during mold forming and convert it into two forces in opposite directions, thereby achieving the overall forming of parts such as anisotropic S-bend partitions.

[0006] The present invention provides a hydraulic forming die for a sheet metal part of a different-direction S-bend partition, wherein the sheet metal part of the different-direction S-bend partition comprises: a web surface and upper and lower bends arranged on both sides of the web surface; the hydraulic forming die comprises: a cover plate, a mold, and a base;

[0007] The cover plate is superimposed on the mold, and the sheet material is arranged between the cover plate and the mold; the upper surface of the mold, the lower surface of the cover plate and the upper and lower surfaces of the web surface have the same outer contour;

[0008] The base is provided with a groove for clamping the cover plate and the mold; a cylindrical helical compression spring is provided on the upper surface of the groove, and the mold is connected to the cylindrical helical compression spring; the side surface of the groove and the inner surface of the mold are consistent with the outer contour of the upper curved edge; the outer surface of the mold is consistent with the outer contour of the lower curved edge;

[0009] The cylindrical helical compression spring is compressed during the integral forming process, and the mold is fitted to the upper surface of the groove;

[0010] Positioning pin holes are arranged on the cover plate, the mold and the base.

[0011] Optionally, when the cylindrical helical compression spring is not compressed, the height is not less than the depth of the groove.

[0012] Optionally, the cover plate is 1 material thickness away from the inner side of the base groove, which is used for bending the upper edge of the formed part.

[0013] Optionally, the outer side of the mold is one material thickness thinner than the outer side of the cover plate, and is used for forming the lower bend of the part.

[0014] Optionally, a plurality of spring grooves are provided on the base, and the cylindrical helical compression springs are arranged in the spring grooves.

[0015] Optionally, the cover plate, mold and base are rigid structures, and the roughness of the upper surface and side surfaces of the mold and the inner side of the base groove is no more than Ra6.3.

[0016] Optionally, the thickness of the cover plate is consistent with the height of the upper curved edge of the part;

[0017] The depth of the groove is consistent with the sum of the thickness of the cover plate, the mold and one material.

[0018] The second aspect of the present invention further provides a method for hydraulically forming a sheet metal part such as a heterogeneous S-bend partition, using the hydroforming die for the sheet metal part such as a heterogeneous S-bend partition as described in any one of the first aspects, comprising:

[0019] 1) Install the mold on the cylindrical helical compression spring on the base groove;

[0020] 2) Place the unfolded part to be formed on the upper surface of the mold and align it with the positioning pin hole on the mold;

[0021] 3) Place the cover plate on top of the part and use the positioning pins and the pin holes on the additional ear pieces of the part to position it;

[0022] 4) Place the combined mold on the hydraulic press workbench, cover it with the auxiliary rubber of the protective cover plate, and put the workbench into the pressure cylinder of the hydraulic press;

[0023] 5) The hydraulic press continuously pressurizes the combined mold through boosting, compresses the cylindrical helical compression spring to make the cover plate and the mold move downward, and the rough material of the outer part of the mold is formed into a downward curved edge under the action of the rubber, and the inner part of the mold and the base is formed into an upward curved edge, thereby realizing the overall forming of the different-direction S-curve;

[0024] 6) The hydraulic press releases pressure and returns oil, the workbench is pulled out, and the cylindrical helical compression spring moves upward to restore the initial state;

[0025] 7) After hydraulic forming, remove the mold and cover plate and trim and correct the parts.

[0026] The present invention provides a hydraulic forming mold and method for sheet metal parts such as anisotropic S-bend partitions. The mold uses an elastic mechanism to convert a unidirectional power source during mold rubber forming into forces in two opposite directions, thereby realizing the overall forming of sheet metal parts such as anisotropic S-bend partitions, solving the problems of a large number of tooling required for the forming of anisotropic bent parts, a long process flow, high cost and low efficiency. The mold of the present application can be used to form parts at one time, so the mold used in the present application has significant advantages such as high forming efficiency and low cost, and the production efficiency can be increased by at least 80%. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the different-direction S-bend partition parts involved in this application;

[0028] Figure 2 This is a schematic diagram of the different-direction S-bend partition part of the present application before forming;

[0029] Figure 3 This is a schematic diagram of the rubber forming of the anisotropic S-bend partition parts by the overall mold of the present application;

[0030] Figure 4 This is a schematic diagram of the overall mold of the present application for trimming the different-direction S-bend partition parts;

[0031] Figure 5 It is a schematic diagram of the different-direction S-bend partition part after the integral mold forming of the present application;

[0032] Figure 6 This is a schematic diagram of a hydraulic forming die for a sheet metal part such as an anisotropic S-bend partition of the present application;

[0033] Description of reference numerals:

[0034] 1-cover plate; 2-tire; 3-base; 4-parts; 5-movable pin; 6-cylindrical helical compression spring. DETAILED DESCRIPTION

[0035] The present application is further described in detail below in conjunction with the accompanying drawings of the embodiments.

[0036] like Figure 1-6 As shown, the defects of the sheet metal parts structure of the heterogeneous S-bend partition and the existing forming method thereof are as follows:

[0037] See attached Figure 1 Part structure, because the part has a reverse bend, if the mold can form a sheet metal part such as a partition with an S-shaped bend in one time, in the past, two sets of tooling were generally used to form the bends separately during rubber hydraulic forming. For parts with concave and convex curves, the concave bend is closer to the tire than the convex bend. Therefore, the first set of tooling is used to form the concave bend first, and the second set of tooling is used to form the convex bend to avoid and protect the formed concave bend. Two sets of molds are required, which is costly, and repeated loading and unloading is time-consuming and labor-intensive.

[0038] The structure of the hydraulic forming die for the sheet metal parts of the anisotropic S-bend partition of the present application is as follows: Figure 2-6 shown.

[0039] In order to overcome the above problems existing in the existing parts forming process, such as time-consuming and labor-intensive loading and unloading of molds and low forming efficiency, the present application provides a kind of sheet metal parts ( Figure 1 ) A hydraulic forming mold and method, the mold comprises a cover plate 1, a mold 2, and a base 3. The cover plate 1 is superimposed on the mold 2, and the upper surface of the mold 2 is in contact with the belly surface of the part 4; the combination of the cover plate 1 and the mold 2 matches the base 3, and the inner side of the base 3 is in contact with the bent edge of the part after forming; the top surface of the cover plate 1 and the mold 2 are provided with mutually matching positioning pins, and the mold 2 and the base 3 are provided with mutually matching movable pins 5; the base 3 is provided with an elastic mechanism - a cylindrical helical compression spring, which is connected to the mold 2; the lower surface of the mold 2 is in contact with the upper surface of the base 3 under the action of pressure.

[0040] The cover plate 1 is 1 material thickness away from the inner side of the base 3, and is used for bending one side of the formed part;

[0041] Optionally, the outer side of the mold 2 and the outer side of the cover plate 1 should differ by 1 material thickness, so as to form an asymmetric bend on the other side of the part.

[0042] Among them, the combined mold base 3 is provided with an elastic mechanism - a cylindrical helical compression spring 6, which is connected to the mold 2. During operation, the spring 6 is compressed by the pressure generated by the hydraulic press. After forming, the pressure disappears and the spring 6 returns to its original state.

[0043] The cover plate 1, the mold 2 and the base 3 are rigid structures, and the roughness of the upper surface and the side surface of the mold 2 and the inner side of the base is not greater than Ra6.3.

[0044] Introducing again the use of the combined die for sheet metal parts such as the S-bend partition

[0045] Refer to the attached manual for the method of using the above-mentioned combined mold to hydraulically perform the S-bend partition type sheet metal parts. Figure 1 To Attachment Figure 6 , which is characterized by the following contents:

[0046] 1) The mold 2 is placed on the base 3, and the unfolded material of the different-direction S-bend partition parts to be formed is placed on the upper surface of the mold 2 and aligned through the positioning pin holes on the mold;

[0047] 2) Place the cover plate on the part, and use the positioning pins and the pin holes on the part's additional ear piece to position and connect the part with the mold and cover plate;

[0048] 3) Place the combined mold on the workbench of the hydraulic press, place an auxiliary rubber to protect the cover plate on the mold, and send it into the pressure cylinder of the hydraulic press along with the workbench;

[0049] 4) The hydraulic press continuously pressurizes the combined mold through boosting, compresses the spring, and moves the cover plate and the mold downward. At this time, the mold and the inner side of the base form an upward curved edge of the part; the outer side of the mold forms a downward curved edge under the action of the rubber and the pressure of the hydraulic press, thereby realizing the overall forming of the sheet metal parts such as the diaphragm with different S-curved edges;

[0050] 5) The hydraulic press releases pressure and returns oil, pulls out the workbench, and the spring moves upward to restore the initial state.

[0051] 6) After hydraulic forming, remove the mold and cover from the base of the combined mold, and continue to trim and correct the curved edges of the parts.

[0052] 7) After forming, remove the parts and return the mold to storage.

Claims

1. A hydraulic forming die for sheet metal parts of different-direction S-bend partitions, characterized in that: The sheet metal parts of the different-direction S-bend partition include: a web surface and upper and lower bends arranged on both sides of the web surface; the hydraulic forming mold includes: a cover plate, a mold, and a base; The cover plate is superimposed on the mold, and the sheet material is arranged between the cover plate and the mold; the upper surface of the mold, the lower surface of the cover plate and the upper and lower surfaces of the web surface have the same outer contour; The base is provided with a groove for clamping the cover plate and the mold; a cylindrical helical compression spring is provided on the upper surface of the groove, and the mold is connected to the cylindrical helical compression spring; the outer shape of the side surface of the groove and the inner surface of the mold is consistent with the outer contour of the upper curved edge; the outer surface of the mold is consistent with the outer contour of the lower curved edge; The cylindrical helical compression spring is compressed during the integral forming process, and the mold is fitted to the upper surface of the groove; Positioning pin holes are arranged on the cover plate, the mold and the base.

2. The hydraulic forming die for the sheet metal parts of the heterogeneous S-bend partition type according to claim 1 is characterized in that: When the cylindrical helical compression spring is not compressed, its height is not less than the depth of the groove.

3. The hydraulic forming die for the sheet metal parts of the heterogeneous S-bend partition type according to claim 1 is characterized in that: The cover plate is 1 material thickness away from the inner side of the base groove and is used for bending the upper edge of the formed part.

4. The hydraulic forming die for the sheet metal parts of the heterogeneous S-bend partition type according to claim 1 is characterized in that: The outer side of the mold is one material thickness less than the outer side of the cover plate and is used for forming the lower bend of the part.

5. The hydraulic forming die for the sheet metal parts of the heterogeneous S-bend partition type according to claim 1 is characterized in that: A plurality of spring grooves are arranged on the base, and the cylindrical helical compression springs are arranged in the spring grooves.

6. The hydraulic forming die for the sheet metal parts of the heterogeneous S-bend partition type according to claim 1 is characterized in that: The cover plate, mold and base are rigid structures, and the roughness of the upper surface and side surfaces of the mold and the inner side of the base groove is no more than Ra6.

3.

7. The hydraulic forming die for the sheet metal parts of the heterogeneous S-bend partition type according to claim 1 is characterized in that: The thickness of the cover plate is consistent with the height of the upper bending edge of the part; The depth of the groove is consistent with the sum of the thickness of the cover plate, the mold and one material.

8. A method for hydraulically forming a sheet metal part such as a heterogeneous S-bend partition, using a hydroforming die for a heterogeneous S-bend partition according to any one of claims 1 to 7, characterized in that: include: 1) Install the mold on the cylindrical helical compression spring on the base groove; 2) Place the unfolded part to be formed on the upper surface of the mold and align it with the positioning pin hole on the mold; 3) Place the cover plate on top of the part and use the positioning pins and the pin holes on the additional ear pieces of the part to position it; 4) Place the combined mold on the hydraulic press workbench, cover it with the auxiliary rubber of the protective cover plate, and put the workbench into the pressure cylinder of the hydraulic press; 5) The hydraulic press continuously pressurizes the combined mold through boosting, compresses the cylindrical helical compression spring to make the cover plate and the mold move downward, and the rough material of the outer part of the mold is formed into a downward curved edge under the action of the rubber, and the inner part of the mold and the base is formed into an upward curved edge, thereby realizing the overall forming of the different-direction S-curve; 6) The hydraulic press releases pressure and returns oil, the workbench is pulled out, and the cylindrical helical compression spring moves upward to restore the initial state; 7) After hydraulic forming, remove the mold and cover plate and trim and correct the parts.

Images