A cylindrical part rolling and liquid filling deep drawing forming device and method

Abstract

The present invention discloses a cylindrical part rolling and liquid-filling deep drawing forming device, comprising a rolling punch, a die and a pressure ring, wherein a conical rolling surface is arranged at the end of the rolling punch; the rolling punch can move in the axial and radial directions of the inner cavity of the die, and can rotate around its own central axis and the central axis of the inner cavity of the die; the die is provided with a channel for filling the inner cavity of the die with liquid medium, and a filling valve is arranged on the channel. The present invention also discloses a cylindrical part rolling and liquid-filling deep drawing forming method, wherein the aforementioned cylindrical part rolling and liquid-filling deep drawing forming device is used to perform deep drawing on sheet metal. The cylindrical part rolling and liquid-filling deep drawing forming device and method of the present invention apply local drawing to the sheet metal by swinging the rolling punch, thereby completing the overall drawing of the part. During the drawing process, liquid pressure is applied to the other side of the sheet metal to improve the stress state of the sheet metal, which can effectively improve the forming limit of the sheet metal and the forming quality of the part, thereby saving costs.

Description

Technical Field

[0001] The invention belongs to the technical field of metal processing, and in particular relates to a device and method for rolling and liquid-filling deep drawing of a cylindrical part. Background Art

[0002] At present, the deep drawing process is used to manufacture metal cylindrical parts, which has the advantages of high productivity, high material utilization and low production cost. It is widely used in the fields of automobiles, instruments and meters, electronics, aerospace, etc.

[0003] However, due to the characteristics of the process itself, the friction between the die and the metal sheet, especially the blank holder ring exerts a blank holder force on the sheet. If the pressure exerted by the blank holder ring is too small, the flange area is prone to instability and wrinkling. If the blank holder force is too large, the friction between the die and the sheet is too large, which restricts the flow of material from the flange area to the die, resulting in the cylinder being prone to cracking and uneven wall thickness during the drawing process.

[0004] Therefore, for cylindrical parts with large drawing coefficients and large aspect ratios, material flow is difficult and deformation is uneven. Traditional deep drawing requires multiple sets of molds for multiple deep drawing, resulting in low manufacturing precision, increased production costs and extended production cycles for such cylindrical parts. Summary of the invention

[0005] The object of the present invention is to provide a device and method for rolling and liquid-filling deep drawing of a cylindrical part, so as to effectively solve the shortcomings of the prior art.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] A cylindrical part rolling and liquid-filling deep drawing forming device comprises a rolling punch, a die and a blank holder, wherein the blank holder is arranged above the die and is used to clamp the sheet material to be formed between the blank holder and the die, and a conical rolling surface is arranged at the end of the rolling punch; the rolling punch can move in the axial direction and radial direction of the inner cavity of the die, and can rotate around its own central axis and the central axis of the inner cavity of the die;

[0008] The die is provided with a channel for filling the inner cavity of the die with liquid medium, and the channel is provided with a filling valve, and the filling valve is used to control the liquid pressure in the inner cavity of the die.

[0009] Compared with the prior art, the present invention's cylindrical part rolling and liquid-filling deep drawing forming device applies local drawing to the sheet material through the up-down and left-right movement of the rolling punch and its own rotation and rotation around the central axis of the die, thereby completing the overall drawing of the part. During the drawing process, liquid pressure is applied to the other side of the sheet material to improve the stress state of the sheet material, which can effectively improve the forming limit of the sheet material and the forming quality of the part, save costs, and solve the problems of low drawing limit, uneven wall thickness, cracking and wrinkling caused by difficult material flow.

[0010] Furthermore, the central axis of the rolling punch forms an acute angle a with the vertical plane, and a cone generatrix constituting the conical rolling surface is parallel to the sheet material.

[0011] By setting the central axis of the rolling punch to form an acute angle a with the vertical plane and the cone generatrix to be parallel to the sheet material, the rolling punch can accumulate small deformations to the overall deformation of the sheet material by rolling the local sheet material, thereby reducing the forming force of the sheet material and improving the uniformity of sheet material forming.

[0012] Furthermore, a first annular groove is provided on the position of the blank holder in contact with the sheet material for installing a first sealing ring; a second annular groove is provided on the die in contact with the blank holder for installing a second sealing ring.

[0013] The annular groove and the sealing ring are provided to ensure the sealing performance, thereby ensuring the stability and effectiveness of the operation of the cylindrical part rolling, liquid filling and deep drawing forming device of the present invention.

[0014] Furthermore, the channel is arranged at a central position of the bottom of the die.

[0015] Setting the channel at the center of the bottom of the die can ensure uniform liquid pressure and facilitate production.

[0016] Furthermore, the upper port of the inner cavity of the female mold is provided with a rounded corner.

[0017] Set rounded corners to facilitate the forming of the sheet.

[0018] The present invention also discloses a method for rolling and liquid-filling deep drawing of a cylindrical part, which uses the aforementioned rolling and liquid-filling deep drawing device for a cylindrical part to perform deep drawing on a sheet material, and specifically comprises the following steps:

[0019] S1, place the sheet on the die, the blank holder is pressed down and in contact with the sheet, and a blank holder force F is applied to the blank holder; then the filling valve is opened, and liquid medium is injected into the inner cavity of the die, and the liquid medium is kept at a certain pressure P;

[0020] S2, the rolling punch moves downward, and at the same time, the rolling punch rotates around its own central axis; after the rolling punch contacts the initial upper end surface of the sheet, it continues to move downward for a distance h to a certain height position, thereby completing the local rolling and drawing;

[0021] S3, the rolling punch moves upward, separates from the sheet and returns to the initial position;

[0022] S4, the rolling punch moves a distance r in the radial direction of the inner cavity of the die to a certain horizontal position; the rolling punch rotates around its own central axis and moves downward to the height position where the punch was last located in step S2;

[0023] S5, while the rolling punch rotates around its own central axis, it also rotates around the central axis of the inner cavity of the die with a radius r;

[0024] S6, repeating steps S3, S4 and S5 in sequence, wherein the distance r of the radial movement of the rolling punch in the inner cavity of the die gradually increases until the rolling and deep drawing forming at the height position is completed;

[0025] S7, the rolling punch moves upward again, and returns to the initial position after being separated from the sheet; then steps S2, S3, S4, S5 and S6 are repeated in sequence, wherein the distance h that the rolling punch continues to move downward after contacting the initial upper end surface of the sheet gradually increases;

[0026] The rolling punch is pressed down to different heights several times and moves radially to different horizontal positions in the die, thereby completing the rolling and drawing at each height and horizontal position until the drawing distance reaches the set height, and finally completing the cylindrical part forming and removing the part.

[0027] Compared with the prior art, the present invention's cylindrical part rolling and liquid filling deep drawing method completes local rolling and deep drawing through the up and down movement and "rotation" of the rolling punch, and completes the overall deep drawing through the left and right movement and "revolution" of the rolling punch. Compared with traditional deep drawing, it has the following beneficial effects:

[0028] 1) The rolling punch gradually completes the deep drawing of the overall part through local rolling and drawing, improves the uneven deformation of the material, and changes the fluidity of the material;

[0029] 2) Increase the filling pressure in the inner cavity of the die to change the stress and strain state of the sheet, effectively slow down the speed of thinning of the sheet wall thickness, and improve the forming limit of the sheet;

[0030] 3) Rolling and liquid filling deep drawing can effectively reduce the drawing force, reduce the tonnage requirements of the equipment and the production cost.

[0031] Furthermore, an initial value of a distance r of radial movement of the rolling punch in the inner cavity of the die is less than half of an outer diameter of the rolling punch.

[0032] This limitation allows the rolling punch to fully and completely roll the sheet metal, preventing the unrolled parts from appearing. At the same time, the rolling punch will not touch the side wall of the inner cavity of the die, ensuring safety and normal forming of the sheet metal.

[0033] Furthermore, an initial value of a distance h that the rolling punch continues to move downward after contacting the sheet material is less than half of the inner cavity depth of the die.

[0034] This limitation allows a certain amount of liquid medium to be present in the inner cavity of the die when the sheet metal is being formed, so that the liquid medium maintains a certain pressure.

[0035] Furthermore, in step S1, the size of the blank holding force F is adjusted according to the deformation of the sheet material.

[0036] During the sheet forming process, the blank holding force F is adjusted according to the deformation of the sheet, so that the sheet at the clamping position can flow more toward the die.

[0037] Furthermore, in step S1, the magnitude of the pressure P is adjusted according to the stress and strain state of the sheet material.

[0038] The filling pressure is varied to effectively improve the stress and strain state of the sheet metal at different forming stages and increase the forming limit of the sheet metal.

[0039] In order to more clearly understand the present invention, specific embodiments of the present invention will be described below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural schematic diagram of the cylindrical part rolling and liquid filling deep drawing forming device of the present invention;

[0041] Figure 2 It is a schematic diagram of the initial state of rolling and filling liquid in the present invention;

[0042] Figure 3 It is a schematic diagram of local rolling and drawing of the rolling punch in the present invention;

[0043] Figure 4 It is a schematic diagram of the rolling punch rotating around the central axis of the die in the present invention;

[0044] Figure 5 It is a schematic diagram of the final forming of the cylindrical part in the present invention.

[0045] Wherein, the accompanying drawings are marked as follows:

[0046] 10. Rolling punch; 11. Conical rolling surface; 12. Conical generatrix; 20. Die; 21. Second annular groove; 22. Second sealing ring; 23. Fillet; 30. Pressure ring; 31. First annular groove; 32. First sealing ring; 40. Sheet material; 50. Liquid medium; 60. Channel; 70. Filling valve. DETAILED DESCRIPTION

[0047] In order to solve the shortcomings and defects of the prior art, the present invention provides a cylindrical part rolling liquid filling deep drawing forming device and method, which applies local deep drawing to the sheet material by swinging the rolling punch, thereby completing the overall deep drawing of the part. During the deep drawing process, liquid pressure is applied to the other side of the sheet material to improve the stress state of the sheet material, which can effectively improve the forming limit of the sheet material and the forming quality of the part, and save costs.

[0048] like Figures 1 to 5 As shown, a cylindrical part rolling and liquid filling deep drawing forming device includes a rolling punch 10, a die 20 and a pressure ring 30.

[0049] The blank holder 30 is movably disposed above the die 20 , and is used to clamp the sheet material 40 to be formed between the blank holder 30 and the die 20 .

[0050] The end of the rolling punch 10 is provided with a conical rolling surface 11; the rolling punch 10 can move in the axial and radial directions of the inner cavity of the die 20, and can rotate around its own central axis and the central axis of the inner cavity of the die 20. Specifically, the rolling punch 10 is arranged on a machine tool (not shown in the figure), which is an existing machine tool. The rolling punch 10 is installed on the machine tool, and can move in the axial and radial directions of the inner cavity of the die 20 driven by the machine tool, and can rotate around the rolling punch 10 itself The central axis and the central axis of the inner cavity of the die 20. More specifically, the central axis of the rolling punch 10 forms an acute angle a with the vertical plane, and a conical generatrix 12 constituting the conical rolling surface 11 is parallel to the sheet 40. When the rolling punch 10 rolls the sheet material 40 , the rolling punch 10 which forms a certain angle with the vertical plane can accumulate small deformation to the overall deformation of the sheet material 40 by rolling the local sheet material 40 , thereby reducing the forming force of the sheet material 40 and improving the uniformity of the forming of the sheet material 40 .

[0051] The die 20 is provided with a channel 60 for filling the liquid medium 50 into the inner cavity of the die 20. The channel 60 is provided with a filling valve 70. The filling valve 70 is used to control the liquid pressure in the inner cavity of the die 20. The filling valve 70 is an existing conventional technology and will not be described in detail here.

[0052] More specifically, the position of the blank holder 30 in contact with the sheet material 40 is provided with a first annular groove 31 for installing a first sealing ring 32; the position of the die 20 in contact with the blank holder 30 is provided with a second annular groove 21 for installing a second sealing ring 22. Specifically, the first annular groove 31 is provided at a position close to the opening on the inner cavity of the die 20, the first sealing ring 32 matches the first annular groove 31, and the second sealing ring 22 matches the second annular groove 21, so as to perform effective sealing.

[0053] More specifically, the channel 60 is disposed at the center of the bottom of the die 20, and the central axis of the channel 60 coincides with the central axis of the inner cavity of the die 20. This ensures that the liquid pressure in the die 20 is uniform, and facilitates the processing and manufacturing of the channel 60.

[0054] More specifically, the upper end of the inner cavity of the die 20 is provided with a rounded corner 23 , and the rounded corner 23 is provided so that the sheet material 40 can better fit the inner cavity of the die 20 when deforming, so as to facilitate the forming of the sheet material 40 .

[0055] The cylindrical part rolling and liquid filling deep drawing forming device of the present invention, when in use, drives the rolling punch 10 to move up and down, move left and right, rotate around its own central axis and rotate around the central axis of the inner cavity of the die 20 through the machine tool, gradually applies local rolling and deep drawing to the sheet material 40, and then completes the overall deep drawing of the part. During the rolling and stretching process, the inner cavity of the die 20 is filled with a liquid medium 50, so that the liquid pressure acts on the other side of the sheet material 40, thereby improving the stress state of the sheet material 40.

[0056] This embodiment also provides a cylindrical component rolling and liquid filling deep drawing method, which uses the aforementioned cylindrical component rolling and liquid filling deep drawing device to perform deep drawing on the sheet material 40, and specifically includes the following steps:

[0057] S1, the sheet 40 is placed on the die 20, the blank holder 30 is pressed down and in contact with the sheet 40, and an external device is used to apply a blank holder force F to the blank holder 30; then the filling valve 70 is opened, and the liquid medium 50 is injected into the inner cavity of the die 20, and the liquid medium 50 is kept at a certain pressure P, such as Figure 2 As shown;

[0058] S2, the machine tool drives the rolling punch 10 to move downward, and at the same time, the rolling punch 10 rotates around its own central axis; after the rolling punch 10 contacts the initial upper end surface of the sheet 40, it continues to move downward for a distance h to a certain height position, thereby completing the local rolling and drawing. Figure 3 As shown;

[0059] S3, the rolling punch 10 moves upward, separates from the sheet material 40 and returns to the initial position;

[0060] S4, the rolling punch 10 moves a distance r in the radial direction of the inner cavity of the die 20 to a certain horizontal position, that is, the rolling punch 10 moves a distance r to the left; the rolling punch 10 rotates around its own central axis and moves downward to the height position where the punch was last located in step S2, such as Figure 4 As shown;

[0061] S5, the rolling punch 10 rotates around its own central axis while rotating around the central axis of the inner cavity of the die 20 with a radius r;

[0062] S6, repeating steps S3, S4 and S5 in sequence, wherein the radial movement distance r of the rolling punch 10 in the inner cavity of the die 20 gradually increases until the rolling deep drawing forming at the height position is completed, such as Figure 4 As shown;

[0063] S7, the rolling punch 10 moves upward again, and returns to the initial position after being separated from the sheet material 40; then steps S2, S3, S4, S5 and S6 are repeated in sequence; wherein the distance h that the rolling punch 10 continues to move downward after contacting the initial upper end surface of the sheet material 40 gradually increases;

[0064] After the rolling punch is pressed down to different height positions 10 times and moves to different horizontal positions in the radial direction of the die 20, the rolling and drawing forming at each height position and horizontal position is completed until the drawing distance reaches the set height, and finally the cylindrical part is formed. Figure 5 as shown, and remove the parts.

[0065] Specifically, in this embodiment, the initial value of the distance r of the radial movement of the rolling punch 10 in the inner cavity of the die 20 is less than half of the outer diameter of the rolling punch 10, that is, the distance r is less than the length of the cone generatrix 12, so that the rolling punch 10 can fully and comprehensively roll the sheet material 40 to prevent the unrolled parts; at the same time, it can ensure that the rolling punch 10 will not touch the side wall of the inner cavity of the die 20 to ensure safety and normal forming of the sheet material 40.

[0066] More specifically, the initial value of the distance h that the rolling punch 10 continues to move downward after contacting the sheet material 40 is less than half the depth of the inner cavity of the die 20, so that when the sheet material 40 is formed, there is a certain amount of liquid medium 50 in the inner cavity of the die 20, so that the liquid medium 50 maintains a certain pressure.

[0067] More specifically, in step S1, the size of the blank holder force F is adjusted according to the deformation of the sheet material 40, and at the same time, the size of the pressure P is adjusted according to the stress and strain state of the sheet material 40. During the forming process of the sheet material 40, the blank holder force F is adjusted according to the deformation of the sheet material 40, so that the sheet material 40 at the clamping position can flow more toward the die 20. At the same time, adjusting the size of the pressure P can effectively improve the stress and strain state of the sheet material 40 at different forming stages, thereby improving the forming limit of the sheet material 40.

[0068] Compared with the prior art, the cylindrical part rolling and liquid-filling deep drawing forming device of the present invention applies local drawing to the sheet material through the up-and-down and left-and-right movement of the rolling punch and its own rotation and rotation around the central axis of the die, thereby completing the overall drawing of the part. During the drawing process, liquid pressure is applied to the other side of the sheet material to improve the stress state of the sheet material, which can effectively improve the forming limit of the sheet material and the forming quality of the part, save costs, and solve the problems of low drawing limit, uneven wall thickness, cracking and wrinkling caused by difficult material flow. The cylindrical part rolling and liquid-filling deep drawing forming method of the present invention completes local rolling and drawing through the up-and-down movement and "rotation" of the rolling punch, and completes the overall drawing forming through the left-and-right movement and "revolution" of the rolling punch. Compared with traditional deep drawing, the rolling punch in the present invention gradually completes the deep drawing of the overall part through local rolling and drawing, thereby improving the uneven deformation of the material; at the same time, the liquid filling pressure is increased to the inner cavity of the die, which changes the stress and strain state of the sheet material, and can effectively delay the speed of thinning of the sheet material wall thickness and improve the forming limit of the sheet material; in addition, the rolling and liquid filling deep drawing in the present invention can effectively reduce the drawing force, thereby reducing the tonnage requirements and production costs of the equipment.

[0069] The above-mentioned embodiment only expresses one implementation mode of the present invention, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for rolling and liquid-filling deep drawing of a cylindrical part, characterized in that: A cylindrical part rolling and liquid filling deep drawing forming device is used to perform deep drawing forming on a sheet material (40), the cylindrical part rolling and liquid filling deep drawing forming device comprising a rolling punch (10), a die (20) and a blank holder (30), the blank holder (30) being arranged above the die (20), the blank holder (30) being used to clamp the sheet material (40) to be formed between the blank holder (30) and the die (20), the end of the rolling punch (10) being provided with a conical rolling surface (11); the rolling punch (10) can move in the axial and radial directions of the inner cavity of the die (20), and can rotate around its own central axis and the central axis of the inner cavity of the die (20); The die (20) is provided with a channel (60) for filling the inner cavity of the die (20) with a liquid medium (50), and the channel (60) is provided with a liquid filling valve (70), and the liquid filling valve (70) is used to control the liquid pressure in the inner cavity of the die (20); The cylindrical part rolling and liquid filling deep drawing forming method specifically comprises the following steps: S1, placing the sheet (40) on the die (20), pressing the blank holder (30) downward and contacting the sheet (40), applying a blank holder force F to the blank holder (30); then opening the liquid filling valve (70), injecting a liquid medium (50) into the inner cavity of the die (20), and maintaining a certain pressure P of the liquid medium (50); adjusting the size of the blank holder force F according to the deformation of the sheet (40); adjusting the size of the pressure P according to the stress and strain state of the sheet (40); S2, the rolling punch (10) moves downward, and at the same time, the rolling punch (10) rotates around its own central axis; after the rolling punch (10) contacts the initial upper end surface of the sheet material (40), it continues to move downward for a distance h to a certain height position, thereby completing local rolling and drawing; S3, the rolling punch (10) moves upward, separates from the sheet (40) and returns to the initial position; S4, the rolling punch (10) moves a distance r in the radial direction of the inner cavity of the die (20) to a certain horizontal position; the rolling punch (10) rotates around its own central axis and moves downward to the height position where the rolling punch (10) was last located in step S2; S5, the rolling punch (10) rotates around its own central axis while rotating around the central axis of the inner cavity of the die (20) with a radius r; S6, repeating steps S3, S4 and S5 in sequence, wherein the distance r of the radial movement of the rolling punch (10) in the inner cavity of the die (20) gradually increases until the rolling and deep drawing forming at the height position is completed; S7, the rolling punch (10) moves upward again, separates from the sheet material (40) and returns to the initial position; then, steps S2, S3, S4, S5 and S6 are repeated in sequence, wherein the distance h that the rolling punch (10) continues to move downward after contacting the initial upper end surface of the sheet material (40) gradually increases; The rolling punch (10) is pressed down to different height positions multiple times and the die (20) is radially moved to different horizontal positions, thereby completing the rolling and drawing forming at each height position and horizontal position until the drawing distance reaches the set height, and finally completing the forming of the cylindrical part and removing the part.

2. The method for rolling and liquid-filling deep drawing of a cylindrical part according to claim 1, characterized in that: The central axis of the rolling punch (10) forms an acute angle a with the vertical plane, and a conical generatrix (12) constituting the conical rolling surface (11) is parallel to the sheet material (40).

3. The method for rolling and liquid-filling deep drawing of a cylindrical part according to claim 1, characterized in that: A first annular groove (31) is provided at a position on the blank holder (30) that contacts the sheet material (40) for installing a first sealing ring (32); a second annular groove (21) is provided at a position on the die (20) that contacts the blank holder (30) for installing a second sealing ring (22).

4. The method for rolling and liquid-filling deep drawing of a cylindrical part according to claim 1, characterized in that: The channel (60) is arranged at the center position of the bottom of the die (20).

5. The method for rolling and liquid-filling deep drawing of a cylindrical part according to claim 1, characterized in that: The upper end of the inner cavity of the female mold (20) is provided with a rounded corner (23).

6. The method for rolling and liquid-filling deep drawing of a cylindrical part according to claim 1, characterized in that: An initial value of a distance r of radial movement of the rolling punch (10) in the inner cavity of the die (20) is less than half of the outer diameter of the rolling punch (10).

7. The method for rolling and liquid-filling deep drawing of a cylindrical part according to claim 1, characterized in that: The initial value of the distance h that the rolling punch (10) continues to move downward after contacting the sheet material (40) is less than half the inner cavity depth of the die (20).

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