CN1903474A - Procesing equipment capable of improving plate part formation limitation and method therefor - Google Patents

Abstract

The invention provides a processing device and a processing method used for improving the forming limit of plate parts, and relates to a device and a method for processing plate parts. Aiming at the problem that complex parts with large aspect ratio and high forming limit are difficult to form, the present invention provides a processing device and processing method that can improve the forming limit of plate parts. The device includes a fluid medium chamber (1) and a lower die (2), a blankholder (3) and a punch (4) or a forming die (6) are also provided above the lower die (2). The processing method sequentially includes the process of injecting fluid medium into the cavity (1), placing the plate blank, applying blank holder force, and controlling the downward movement of the punch (4) to pressurize. Another processing method only needs to pressurize the fluid medium to thereby It can be formed by applying pressure to the sheet blank. The use of the device and method of the invention can further increase the forming limit of plate parts and realize the formation of complex plate parts with a larger height-to-diameter ratio through one process, thereby improving efficiency and part quality, and facilitating popularization and application.

Description

The processing device and processing method used to improve the forming limit of plate parts

technical field

The invention relates to a device used for processing boards and a method for processing boards using the device.

Background technique

In sheet metal forming, for sheet parts with high forming limit (large amount of deformation) whose shape and size are consistent with the punch, fluid is usually used as the force transmission medium for forming processing. The principle is to make the sheet under the action of fluid back pressure Close to the punch, the back pressure enhances the friction effect between the blank and the punch, forming a beneficial friction force, which can offset part of the tensile stress of the blank at the rounded corner of the punch, improve the bearing capacity of the deformed blank, and thus increase the forming limit of the sheet metal part. The forming technology of plate parts with fluid as the force transmission medium has been paid more and more attention due to its advantages of high process flexibility, simple mold making, and good quality of formed parts. It can overcome the shortcomings of conventional stamping and forming methods, and is especially suitable for forming deformation in one process. High-volume complex sheet metal parts. Since it was proposed, parts with large aspect ratio and complex shape are formed under the action of fluid back pressure, and have been applied to manufacturing industries such as aviation, automobiles, and electronic products. With the development of high-pressure hydraulic system and related control technology, the sheet metal forming technology using fluid as the force transmission medium has received widespread attention at home and abroad and has developed rapidly. For example, Japan's Amino Iron Works and Japan's Toyota Motor Corporation use this technology to process complex plate parts for automobile fenders, and Sweden's AP&T company uses this technology to process deep cylindrical parts with complex profiles.

In recent years, with the wide application of high-strength steel, high-performance aluminum alloy and titanium alloy, the application of metal matrix composites and magnesium alloys has gradually expanded, the structure has developed into complex forms, forming is becoming more and more difficult, and the performance of existing materials has improved The difficulty brought by it also has the complexity brought about by the special structure. For example, the strength of steel is increased from 250MPa to 1000Mpa, and the plasticity is reduced from 45% to 12%; the strength of aluminum alloy is increased from 150MPa to 530Mpa, and the plasticity is reduced from 30% to 10%. Complex parts with larger height-to-diameter ratios and higher forming limits cannot be formed in one process only by back pressure. Multi-pass forming not only causes processing costs and long processing cycles, but also accumulates errors in multi-pass forming. It affects the precision of the parts, and cannot meet the requirements of the special use conditions in the aviation and aerospace fields for the wall thickness and aerodynamic performance of the parts.

Contents of the invention

Aiming at the difficulty of forming complex parts with large aspect ratio and high forming limit and the disadvantages of long processing cycle and high cost in existing processing methods, the present invention provides a processing device and processing method that can improve the forming limit of plate parts. The device and method can further increase the forming limit of plate parts, realize forming complex plate parts with larger height-to-diameter ratio through one process, thereby improving efficiency and part quality.

A processing device that can improve the forming limit of plate parts, it includes a fluid medium chamber 1, the chamber 1 is provided with a liquid injection hole 1-1 communicating with the chamber body 1-2, and the upper end of the chamber 1 is open , the upper part of the cavity 1 is fixedly connected with the lower die 2, which also includes a blank holder 3 and a punch 4 arranged above the lower die 2, and the blank holder 3 is provided with a liquid injection hole 3-1, Both the blank holder 3 and the lower die 2 are provided with inner holes for the male die 4 to pass through. Utilize described device to carry out the method for processing plate parts, its processing process comprises the following steps in sequence:

a. First, connect the liquid injection hole 1-1 on the cavity 1 and the liquid injection hole 3-1 on the blank holder 3 to the hydraulic system, and then inject the fluid medium into the cavity 1-2. The liquid level of the fluid medium substantially flat with the upper surface of the lower die 2;

B, then place the plate blank 9 on the upper surface of the lower die 2;

c. Control the blank holder 3 to go down until it contacts with the plate blank 9;

d. Control the punch 4 to move down in the inner hole of the blank holder 3 and the lower die 2, continue to press down after contacting the blank 9, and pressurize the fluid medium in the cavity 1-2 through the hydraulic system to make it A back pressure P ₂ is generated on the blank 9, and at the same time, a fluid medium is injected into the gap 7 through the liquid injection hole 3-1, and a radial pressure P ₁ is applied to the blank 9 by fluid pressure until the blank 9 is completely pressed into the bottom. Die 2, the machining process ends;

e. Relieve the back pressure P ₂ and radial pressure P ₁ , then control the punch 4 and blank holder 3 to move up, and take out the formed parts.

Another processing device that can improve the forming limit of plate parts includes a fluid medium chamber 1, the chamber 1 is provided with a liquid injection hole 1-1 communicating with the chamber 1-2, and the upper end of the chamber 1 Opening, the lower die 2 is fixedly connected above the cavity 1, the lower die 2 is provided with an inner hole, and it also includes a forming die 6 arranged above the lower die 2, and the forming die 6 is provided with A liquid injection hole 6-1, a groove 6-2 is provided at a position where the lower bottom surface of the forming die 6 matches the inner hole of the lower die 2 . Utilize described device to carry out the method for processing plate parts, its processing process comprises the following steps in sequence:

a. First, connect the liquid injection hole 1-1 on the cavity 1 and the liquid injection hole 3-1 on the blank holder 3 to the hydraulic system, and then inject the fluid medium into the cavity 1. The upper surface of the die 2 is substantially flat;

B, then place the plate blank 9 on the upper surface of the lower die 5;

c. Control the forming die 6 to descend until it contacts with the plate blank 9;

d. Inject the fluid medium into the gap 7 through the liquid injection hole 6-1, and apply radial pressure P ₁ to the plate blank 9 through the fluid pressurization, and at the same time pressurize the fluid medium in the cavity 1-2 through the hydraulic system to make It produces a back pressure P ₂ on the sheet blank 9, and the sheet blank 9 is deformed under the action of hydraulic pressure, and gradually leans against the groove 6-2 of the forming die 6 until the sheet blank 9 is completely attached to the groove 6-2 On, the processing process ends;

e. Relieve the back pressure P ₂ and radial pressure P ₁ , then control the forming die 6 to move up and take out the formed parts.

The present invention has the following advantages:

1. The device of the present invention is used to forcibly apply radial hydraulic thrust to the plate blank, and a lubricating oil film can be formed on the upper and lower surfaces of the flange area of the blank, which can reduce the gap between the blank and the lower die and blank holder or between the blank and the lower concave. The friction between the mold and the forming die ensures that the surface of the blank is fully protected, and the formed parts are not easily scratched, thereby improving the surface quality of the parts.

2. Forcibly applying radial hydraulic thrust to the plate blank, combined with the back pressure, can significantly reduce the tensile stress of the deformed blank, avoid cracking defects, increase the forming limit, and improve the uniformity of the wall thickness distribution of the part.

3. Forcibly apply radial hydraulic thrust to the plate blank, combined with the back pressure, the plate parts have good moldability and shape stability, small rebound after hydraulic unloading, and high dimensional accuracy. For parts with the same deformation, it is better than only Compared with the forming method of back pressure, the forming method with radial pressure can improve the uniformity of part wall thickness by more than 10%, so it is beneficial to popularization and application.

Description of drawings

Fig. 1 is a schematic structural diagram of a specific embodiment 1, and Fig. 2 is a schematic structural diagram of a specific embodiment 2.

Detailed ways

Specific Embodiment 1: This embodiment is a processing device that can improve the forming limit of plate parts. Referring to FIG. The liquid injection hole 1-1 is used to inject fluid medium into the cavity 1 through the liquid injection hole 1-1 during operation; the upper end of the cavity 1 is open, and the lower die 2 is fixed above the cavity 1, and There is a sealing ring 8 between the lower die 2 to prevent leakage of the fluid medium; it also includes a blank holder 3 and a punch 4 arranged above the lower die 2, and the blank 9 is sandwiched between the blank holder 3 and the lower die 2, a liquid injection hole 3-1 is provided on the blank holder 3, and a gap 7 suitable for the thickness of the plate to be formed is left between the lower die 2 and the blank holder 3, and the liquid injection hole 3-1 It communicates with the gap 7, so that the injected fluid medium exerts radial pressure on the blank 9; a sealing ring 5 is provided on the outer periphery of the gap 7, and the purpose is to avoid injection into the gap 7 after the pressure ring 3 and the lower die 2 are closed. The fluid medium overflows outward; the inner hole for the punch 4 to pass is provided on the binder ring 3 and the lower die 2, and the outer diameter of the punch 4 is smaller than that of the binder ring 3 and the lower die at the same time. 2, this can facilitate the movement of the punch 4 up and down; the size difference between the outer diameter of the punch 4 and the inner diameter of the lower die 2 is greater than the thickness of the plate to be formed, so that the plate blank 9 can be easily pressed into the lower concave Die 2 inside. In actual operation, it is only necessary to control the size difference between the outer diameter of the punch 4 and the inner diameter of the lower die 2 to be 1.1 times the thickness of the plate to be formed. Of course, this value can also be slightly larger or smaller, and the present invention can be realized. the goal of.

In this way, when the punch 4 goes down to press the blank 9, the blank can be pressed into the lower die 2. After the blank 9 is pressed into the lower die 2, the gap between the lower die 2 and the blank holder 3 The flange area of the blank is formed in part, and a lubricating oil film can be formed on the upper and lower surfaces of the blank in the flange area by controlling the radial pressure applied to the flange area of the blank to a certain extent.

The specific process of utilizing the mold for processing is as follows:

a. First, connect the liquid injection hole 1-1 on the cavity 1 and the liquid injection hole 3-1 on the blank holder 3 to the hydraulic system, and then inject the fluid medium into the cavity 1-2. The liquid level of the fluid medium substantially flat with the upper surface of the lower die 2;

B, then place the plate blank 9 on the upper surface of the lower die 2;

c. Connect the blank holder 3 and the punch 4 to the press, and control the blank holder 3 to go down to contact with the plate blank 9 under the drive of the blank holder slider of the press, and apply the blank holder force at the same time (as shown in the figure 1, F), the purpose of applying blank-holding force is to avoid wrinkling in the flange area of the sheet blank, so in practical applications, the size of the blank-holding force varies according to the size of the blank, but as long as it can avoid the The purpose of wrinkling in the flange area of the billet is sufficient.

d. Driven by the main slider of the press, the punch 4 moves down in the inner hole of the blank holder 3 and the lower die 2 (as shown by V in Figure 1), and continues to press down after contacting the blank 9, while passing The hydraulic system pressurizes the fluid medium in the cavity 1-2 to generate back pressure P ₂ on the plate blank 9, and at the same time injects the fluid medium into the gap 7 through the liquid injection hole 3-1, and pressurizes the plate through the fluid pressure. The blank 9 applies a radial pressure P ₁ until the blank 9 is completely pressed into the lower die 2, and the machining process ends;

e. Relieve the back pressure P ₂ and radial pressure P ₁ , then the main slider drives the punch 4 to move up, the blank holder slider drives the blank holder 3 to move up, and then take out the formed parts.

In this embodiment, the back pressure P ₂ from the fluid medium cavity makes the blank 9 of the plate tightly attached to the punch 4, and a beneficial friction is established between the punch and the blank; the radial hydraulic pressure P ₁ is forced Auxiliary pushes the plate to flow down the die, and at the same time, fluid lubrication is established in the flange area of the blank 2 under the action of a certain blank holder force. The combined effect of the above three can significantly reduce the radial tensile stress of the blank and increase the forming limit of plate parts. For parts that require multi-pass forming, it can significantly save processes and reduce costs.

Specific embodiment two: Referring to Fig. 2, this embodiment includes a fluid medium chamber 1, said chamber 1 is provided with a liquid injection hole 1-1 communicating with the chamber body 1-2, through which the liquid injection hole 1-1 Connected with the hydraulic system, the fluid medium can be injected into the cavity 1; the upper end of the cavity 1 is open, and the lower die 2 is fixed above the cavity 1, and an inner hole is provided on the lower die 2, and the cavity 1 and the concave A sealing ring 8 is provided between the molds 2 to prevent leakage of the fluid medium; it also includes a forming die 6 arranged above the lower die 2, at a position where the lower bottom surface of the forming die 6 is adapted to the inner hole of the lower die 2 There is a groove 6-2. When working, the blank 9 is placed between the forming die 6 and the lower die 2. The blank 9 is gradually deformed under the action of the fluid medium in the cavity 1 and sticks to the groove 6-2. By thus forming parts, the forming die 6 also has a blanking function;

Between the lower die 2 and the forming die 6, there is a gap 7 suitable for the thickness of the plate to be formed, and a liquid injection hole 6-1 is provided on the forming die 6, and the liquid injection hole 6-1 communicates with the gap 7 , so that the injected fluid medium exerts radial pressure on the blank 9; a sealing ring 5 is provided on the outer periphery of the gap 7, the purpose is to prevent the fluid medium injected into the gap 7 after the forming die 6 and the lower die 2 are closed. overflow outward.

The specific processing procedure when using the above-mentioned device to form the plate blank is as follows:

a. First, connect the liquid injection hole 1-1 on the cavity 1 and the liquid injection hole 3-1 on the blank holder 3 to the hydraulic system, and then inject the fluid medium into the cavity 1. The upper surface of the die 2 is substantially flat;

B, then place the plate blank 9 on the upper surface of the lower die 2;

c. Connect the forming die 6 with the press, and control the forming die 6 to descend to contact with the plate blank 9 under the drive of the blank holder slider of the press, and simultaneously apply the blank holder force (as shown by F in Fig. 2 shown), the purpose of applying blank-holding force is to avoid wrinkling in the flange area of the sheet blank. Therefore, in practical applications, the size of the blank-holding force varies according to the size of the blank, but as long as the flange area of the sheet blank can be avoided For wrinkling purposes.

d. Inject the fluid medium into the gap 7 through the liquid injection hole 6-1, and apply radial pressure P ₁ to the plate blank 9 through the fluid pressurization, and at the same time, pressurize the fluid medium in the cavity 1-2 through the hydraulic system to make It produces a back pressure P ₂ on the sheet blank 9, and the sheet blank 9 is deformed under the action of hydraulic pressure, and gradually leans against the groove 6-2 of the forming die 6 until the sheet blank 9 is completely attached to the groove 6-2 On, the processing process ends;

e. Relieve the back pressure P ₂ and radial pressure P ₁ , and then the blank holder slider drives the forming die 6 to move up, and then take out the formed parts.

In this embodiment, the hydraulic pressure in the fluid medium cavity deforms the blank, and the radial pressure P ₁ assists in pushing the sheet to flow into the forming die. This forming method can significantly reduce the radial tensile stress of the blank and reduce the expansion. Shaped area, increase the forming limit of sheet metal parts, and improve the uniformity of wall thickness of parts.

The aluminum alloy AL1100 material is formed by using the above method and the device. Under the condition that the radial pressure and the back pressure of the liquid chamber are both 22.5Mpa, the forming limit of the part is increased from the existing drawing ratio of 2.6 to 3.3.

Claims (10)

1. one kind can be improved the employed processing unit (plant) of plate material parts forming limit, it is characterized in that it comprises fluid media (medium) cavity volume (1), described cavity volume (1) is provided with the liquid hand-hole (1-1) that communicates with cavity (1-2), cavity volume (1) upper end open, described cavity volume (1) top is connected with lower cavity die (2), it also comprises blank holder (3) and the punch (4) that is arranged on lower cavity die (2) top, described blank holder (3) is provided with liquid hand-hole (3-1), all is provided with the endoporus that passes through for punch (4) on described blank holder (3) and lower cavity die (2).

2. according to claim 1ly can improve the employed processing unit (plant) of plate material parts forming limit, the external diameter that it is characterized in that described punch (4) is simultaneously less than the internal orifice dimension of blank holder (3) and lower cavity die (2), and the difference in size of punch (4) external diameter and lower cavity die (2) internal orifice dimension is greater than the thickness of desire shaping plate.

3. according to claim 2ly can improve the employed processing unit (plant) of plate material parts forming limit, the difference in size that it is characterized in that described punch (4) external diameter and lower cavity die (2) internal orifice dimension is 1.1 times of desire shaping panel thickness.

4. describedly can improve the employed processing unit (plant) of plate material parts forming limit according to claim 1,2 or 3, it is characterized in that leaving the space (7) that adapts with desire shaping panel thickness between described lower cavity die (2) and blank holder (3), the periphery of described space (7) is provided with sealing ring (5).

5. describedly can improve the employed processing unit (plant) of plate material parts forming limit according to claim 1,2 or 3, it is characterized in that being provided with sealing ring (8) between described cavity volume (1) and the lower cavity die (2).

6. one kind can be improved the employed processing unit (plant) of plate material parts forming limit, it is characterized in that it comprises fluid media (medium) cavity volume (1), described cavity volume (1) is provided with the liquid hand-hole (1-1) that communicates with cavity (1-2), cavity volume 1 upper end open, described cavity volume (1) top is connected with lower cavity die (2), described lower cavity die (2) is provided with endoporus, it also comprises the shaping die 6 that is arranged on lower cavity die (2) top, shaping die (6) is provided with liquid hand-hole (6-1), and the position that the bottom surface of described shaping die (6) and lower cavity die (2) endoporus adapt is provided with groove (6-2).

7. according to claim 6ly can improve the employed processing unit (plant) of plate material parts forming limit, it is characterized in that leaving the space (7) that adapts with desire shaping panel thickness between described lower cavity die (2) and shaping die (6), the periphery of described space (7) is provided with sealing ring (5).

8. describedly can improve the employed processing unit (plant) of plate material parts forming limit according to claim 6 or 7, it is characterized in that being provided with sealing ring (8) between described cavity volume (1) and the lower cavity die (2).

9. one kind is utilized the described device of claim 1 that plate material parts is carried out method for processing, it is characterized in that process may further comprise the steps successively:

A, at first liquid hand-hole (1-1) on the cavity volume (1) and the liquid hand-hole (3-1) on the blank holder (3) are connected with hydraulic system, inject fluid media (medium) then in cavity (1-2), the upper surface of the liquid level of fluid media (medium) and lower cavity die 2 remains basically stable;

B, place sheet material blank (9) at the upper surface of lower cavity die (2) then;

C, control blank holder (3) come downwards to sheet material blank (9) and contact;

D, control punch (4) move down in the endoporus of blank holder (3) and lower cavity die (2), and continue to press down after blank (9) contact, and by hydraulic system the interior fluid media (medium) of cavity (1-2) being pressurizeed simultaneously makes it produce pressure (P dorsad to sheet material blank (9) ₂), in space (7), inject fluid media (medium) by liquid hand-hole (3-1) simultaneously, and sheet material blank (9) is applied radial pressure (P by pressurized with fluid ₁), all being pressed into lower cavity die (2) up to blank (9), process finishes;

E, general be pressure (P dorsad ₂) and radial pressure (P ₁) release, control then on punch (4) and the blank holder (3) and move, take out formation of parts and get final product.

10. one kind is utilized the described device of claim 6 that plate material parts is carried out method for processing, it is characterized in that process may further comprise the steps successively:

A, at first liquid hand-hole (1-1) on the cavity volume (1) and the liquid hand-hole (3-1) on the blank holder (3) are connected with hydraulic system, inject fluid media (medium) then in cavity volume (1), the upper surface of the liquid level of fluid media (medium) and lower cavity die (2) remains basically stable;

B, place sheet material blank (9) at the upper surface of lower cavity die (2) then;

C, control shaping die (6) come downwards to sheet material blank (9) and contact;

D, in space (7), inject fluid media (medium) by liquid hand-hole (6-1), and sheet material blank (9) is applied radial pressure (P by pressurized with fluid ₁), pressurization makes it produce pressure (P dorsad to sheet material blank (9) to the fluid media (medium) in the cavity (1-2) by hydraulic system simultaneously ₂), sheet material blank (9) is out of shape under hydraulic action, reclines in the groove (6-2) of shaping die (6) gradually, clings to fully on the groove (6-2) up to sheet material blank (9), and process finishes;

E, general be pressure (P dorsad ₂) and radial pressure (P ₁) release, control then on the shaping die (6) and move, take out formation of parts and get final product.