CN103878228B - Sheet material flexible multipoint forming device - Google Patents

Abstract

The invention relates to a flexible multi-point forming device for sheet materials, comprising: a hydraulic container with an opening; a flexible diaphragm installed at the opening, and the flexible diaphragm seals the inside of the hydraulic container to form a hydraulic cavity; a pressure adjustment unit, connected with the hydraulic pressure The cavity is connected; a plurality of pressurizing units are movable relative to the flexible diaphragm; the plurality of pressurizing units move toward the direction of the flexible diaphragm, so that the plate to be formed between the flexible diaphragm and the pressurizing unit will follow the flexible The deformation of the diaphragm into the hydraulic chamber deforms synchronously until the plate to be formed forms a predetermined shape. Since the flexible diaphragm of the present invention can provide matching real-time adjustable and uniform normal force, it can form an effective normal constraint on the plate to be formed, basically eliminate the suspended area in the forming process of the curved stamping part, and can effectively restrain the plate The material is wrinkled. The formed workpiece has good surface quality, uniform thickness, and no defects such as indentation.

Description

Plate flexible multi-point forming device

technical field

The invention relates to the field of curved plate forming, in particular to a plate flexible multi-point forming device.

Background technique

Flexible manufacturing is the development trend of the processing industry. Among them, multi-point forming technology is an advanced manufacturing technology for three-dimensional surface forming of plate parts. At present, research institutions at home and abroad have conducted in-depth research on it.

CN2548792Y divides the forming surface of the forming die into a series of simple-shaped, discretely arranged, and height-adjustable indenters to form a dot-matrix die, and constructs the forming surface of the die to realize plate forming. The biggest advantage of this device is that it can construct different forming curved surfaces by arbitrarily adjusting the position of the indenter to realize the forming of the three-dimensional curved surface of the plate. However, when forming various curved surfaces, especially parts with protruding parts such as spherical surfaces and conical surfaces, there will always be a considerable part of the plate in a suspended state at the initial stage of forming during the forming process. If it is not in contact with the suspended part of the plate, effective normal constraints cannot be imposed on it, resulting in wrinkles and other defects, which not only seriously affect the forming quality, precision and life of the mold, but also sometimes directly lead to the failure of the forming process. .

CN1994611A adopts an elastic cushion, and proposes to sandwich the sheet in a certain elastic cushion for forming in multi-point forming, and rely on the deformation of the elastic cushion to impose normal constraints on the sheet, but in fact, wrinkling is more It appears in the initial stage of forming, and this elastic cushion only works when the upper and lower molds are basically pressed together or at the end of forming, and it cannot completely solve the problem of forming wrinkles.

CN2460239Y proposes a device that does not adjust the position of the indenter in advance, but simultaneously adjusts the displacement and speed of all punches during forming to realize loading and deformation. However, the structure is complicated, the control is difficult, and the cost of the device is high: this device needs to install a set of specially manufactured hydraulic valves and hydraulic cylinders driven by stepping motors or servo motors on each indenter. The rotation speed of the motor is used to control the displacement of the hydraulic cylinder. Due to the need for simultaneous position detection and real-time speed and displacement control of hundreds or even hundreds of pressure heads, the control system can hardly achieve the designed function. Even if the manufacturing is successful, it is expensive. The cost and the instability of the system also make practical application almost impossible.

CN1864884A proposes a combination of multi-point structure and viscous medium control on the upper half mold, and a forming device using viscous medium on the lower half mold. It also adopts the same method of not adjusting the pressure head in advance, but synchronously controlling the rotation of the stepping motor during the forming process. And control the flow and pressure of the viscous medium at the same time to realize the normal constraint on the sheet during the sheet forming process, but the disadvantages of complex structure, difficult control, and high device cost still exist: this device also needs to be installed on each indenter A set of high-power stepping motors is used to realize the deformation of the sheet when the rotating device drives the indenter down during the forming process. This also requires real-time detection of motion parameters (displacement, speed, etc.) of all indenters, and every Each stepper motor needs to be controlled in real time during the deformation process to achieve the final forming purpose. At the same time, multiple electro-hydraulic proportional relief valves are required to control the pressure of the viscous medium.

CN102248053A proposes a plate multi-point forming device with anti-wrinkle function. This device is composed of shape-adjusting units and clamping units arranged in a staggered manner. The shape-adjusting unit forms an envelope shape, and the clamping unit is passively displaced. The function is to clamp the sheet, instead of the blank holder. This device can always impose discontinuous distribution of normal constraints on the sheet during the sheet forming process, but the restricted area is only generated in the action area of the clamping unit, and the sheet in the action area of the shape-adjusting unit is still in the suspended area. Defects such as wrinkling caused by the inability to restrain the area part still cannot be completely eliminated. At the same time, the clamping unit is passively displaced, and the force and displacement during the forming process are uncontrollable, making it difficult to achieve the design goal.

CN102101363A proposes a multi-point forming device based on full normal constraints. The device can adjust the forming surface arbitrarily and is easy to operate. It does not need to adjust any components in real time during the forming process, and there is always a stable and uniform normal pressure On the sheet metal, it can effectively suppress the wrinkling of the sheet metal. However, this device needs to process special hydraulic cylinders, and the manufacturing cost is high. It is also very difficult to ensure the installation and sealing of hundreds of densely arranged hydraulic cylinders. The size of the hydraulic cylinders limits the size of the basic body, which limits the density of the basic body. Forming accuracy is not easy to guarantee. At the same time, affected by the structure of the hydraulic cylinder, the maximum force acting on each basic body is also limited, thus restricting the ability to form complex thick plate surfaces.

Contents of the invention

The purpose of the present invention is to provide a flexible multi-point forming device that can form effective normal constraints on the sheet to be formed, basically eliminate the suspended area in the forming process of the curved stamping part, and can effectively suppress the wrinkling of the sheet.

In order to solve the above-mentioned technical problems, as an aspect of the present invention, a flexible multi-point forming device for sheet materials is provided, including: a hydraulic container, the hydraulic container has an opening; The internal seal forms a hydraulic cavity; the pressure adjustment unit communicates with the hydraulic cavity; a plurality of pressurizing units are arranged movably relative to the flexible diaphragm; the plurality of pressurizing units move toward the direction of the flexible diaphragm, so that the flexible diaphragm and the The plate to be formed between the pressurizing units deforms synchronously with the deformation of the flexible diaphragm into the hydraulic chamber until the plate to be formed forms a predetermined shape.

Further, the pressing unit includes a pressing rod and an elastic element; the sheet material flexible multi-point forming device also includes a bracket, and a plurality of mounting holes are opened on the bracket, and each pressing unit is correspondingly arranged at a mounting hole; wherein, The pressing rod is movably installed in the installation hole, the elastic element is sleeved on the outside of the pressing rod, and one end of the elastic element abuts against the bracket, and the other end abuts against the pressing rod.

Further, the pressurizing unit further includes a pressure head, which is pivotally connected with the end of the pressure rod close to the flexible diaphragm.

Further, the pressure head is pivotably connected to one end of the pressure rod through magnetic adsorption.

Further, the pressurizing unit further includes an adjusting bolt installed on the end of the pressing rod away from the flexible diaphragm.

Further, the sheet material flexible multi-point forming device further includes a pressure applying unit, which is arranged on a side of the pressing rod away from the flexible membrane, so as to drive a plurality of pressing units to move toward the flexible membrane.

Further, the hydraulic container is provided with a clamping groove for clamping the plate to be formed.

Further, the sheet material flexible multi-point forming device also includes a blank holder, and the flexible diaphragm is sealed and connected with the hydraulic container through the blank holder.

Since the flexible membrane of the present invention can provide matching real-time adjustable and uniform normal force, it can form an effective normal constraint on the plate to be formed, basically eliminate the suspended area in the forming process of the curved stamping part, and can effectively restrain the plate The material is wrinkled. The formed workpiece has good surface quality, uniform thickness, and no defects such as indentation. The whole device of the invention has the advantages of reasonable structure, simple operation and use, low manufacturing cost and reliable operation.

Description of drawings

Fig. 1 schematically shows the structural representation of the group of the present invention;

Fig. 2 schematically shows the schematic diagram of the present invention at the end of the stroke;

Fig. 3 schematically shows a schematic diagram of the connection structure of the pressing rod and the pressing head.

Reference signs in the figure: 1. Hydraulic container; 2. Flexible diaphragm; 3. Hydraulic cavity; 4. Limiting support; 5. Plate to be formed; 6. Pressure rod; 7. Elastic element; 8. Support; 9 , pressure head; 10, adjusting bolt; 11, blank holder ring; 12, rod body; 13, joint; 14, first magnet; 15, body; 16, hydraulic joint; 17, pressure applying unit; 18, base; 19 , the second magnet.

detailed description

Embodiments of the invention are described in detail below, but the invention can be practiced in many different ways as defined and covered by the claims.

Please refer to Fig. 1 to Fig. 3, the present invention provides a flexible multi-point forming device for plates, including: a hydraulic container 1, the hydraulic container 1 has an opening; The internal seal of 1 forms a hydraulic chamber 3; the pressure regulating unit communicates with the hydraulic chamber 3; multiple pressurizing units are movable relative to the flexible diaphragm 2; multiple pressurizing units move toward the direction of the flexible diaphragm 2, thereby The plate to be formed 5 disposed between the flexible diaphragm 2 and the pressurizing unit deforms synchronously with the deformation of the flexible diaphragm 2 into the hydraulic chamber 3 until the plate to be formed 5 forms a predetermined shape. For example, the flexible membrane 2 can be made of rubber. In particular, the length of the pressing unit can be designed according to the shape of the curved surface of the plate to be formed.

When in use, first place the plate 5 to be formed on the outside of the flexible diaphragm 2, and then drive the pressurizing unit to move in the direction of the flexible diaphragm 2, when one end of the pressurizing unit pushes the flexible diaphragm 2 toward the inside of the hydraulic container When entering, simultaneously push the sheet material 5 to be formed and clamped between the flexible membrane 2 and the pressurizing unit to undergo the same deformation as the flexible membrane 2 . In this process, there are multiple contact points between the multiple pressurizing units and the plate 5 to be formed, and at the same time, due to the nature of hydraulic transmission, the liquid in the hydraulic container 1 flows through the flexible diaphragm 2 to the entire plate 5 to be formed. The surface provides a uniform normal force to form a normal constraint on the plate 5 to be formed.

Since the flexible diaphragm 2 of the present invention can provide matching real-time adjustable and uniform normal force, it can form an effective normal constraint on the plate 5 to be formed, basically eliminate the suspended area in the forming process of the curved stamping part, and can effectively Suppresses sheet wrinkling. The formed workpiece has good surface quality, uniform thickness, and no defects such as indentation. The whole device of the invention has the advantages of reasonable structure, simple operation and use, low manufacturing cost and reliable operation.

Preferably, the pressure of the hydraulic chamber 3 can be adjusted in real time according to the material, thickness and target shape of the plate 5 to be formed. Preferably, the hydraulic chamber 3 is connected to an external hydraulic control system through a hydraulic joint 16 .

Preferably, the pressing unit includes a pressing rod 6 and an elastic element 7; the sheet flexible multi-point forming device also includes a bracket 8, and a plurality of installation holes are opened on the bracket 8, and each pressing unit is correspondingly arranged in one installation hole Wherein, the pressure rod 6 is movably installed in the installation hole, the elastic element 7 is sleeved on the outside of the pressure rod 6, and one end of the elastic element 7 abuts against the bracket 8, and the other end abuts against the pressure rod 6. When the external driving force is lost to act on the pressing rod 6, under the action of the elastic element 7, the pressing rod 6 can automatically return to the original state.

Preferably, the pressurizing unit further includes a pressure head 9 , which is pivotably connected to the pressure head 9 and the end of the pressure rod 6 close to the flexible membrane 2 . Since the pressure head 9 is pivotally connected to the end of the pressure rod 6, it can adapt to the deformation of the flexible membrane 2 at different angles, that is, it can rotate with the deformation of the flexible membrane 2 .

During the forming process, the indenter 9 will rotate with the deformation of the plate 5 to be formed, and always keep in contact with the plane of the plate 5 to be formed, which increases the contact area between the indenter 9 and the plate 5 to be formed, and avoids the indentation This produces, at the same time, almost the entire surface of the sheet 5 to be formed under the normal constraints of the indenter.

Preferably, please refer to FIG. 3 , the pressure head 9 is pivotably connected to one end of the pressure rod 6 through magnetic adsorption. As shown in FIG. 3 , the compression rod 6 includes a rod body 12 , a joint 13 mounted on the end of the rod body 12 and a first magnet 14 mounted on the joint 13 . The indenter 9 includes a hemispherical body 15 and a second magnet 19 installed on one side of the spherical surface of the body 15 . During installation, insert the ball head of the body 15 into the recess of the joint 13 , so that the body 15 and the joint 13 are attracted and connected to each other under the magnetic attraction force of the first magnet 14 and the second magnet 19 .

Preferably, the pressurizing unit further includes an adjusting bolt 10 installed on the end of the pressing rod 6 away from the flexible membrane 2 . Please refer to FIG. 1 , in one embodiment, all the compression rods 6 have the same length, and in order to form a certain curved surface, an adjusting bolt 10 is respectively installed on the tops of these compression rods 6 . In this way, by adjusting the length of the adjusting bolt 10 protruding from the pressing rod 6, the length of the entire pressing unit can be adjusted, so that a curved surface as shown in FIG. 2 can be formed when pressing. In this way, the pressurization process can be simplified.

For example, in one embodiment, the sheet material flexible multi-point forming device further includes a pressure applying unit 17, such as a press, etc., and the pressure applying unit 17 is arranged on the side of the pressing rod 6 away from the flexible diaphragm 2 to drive multiple The pressurizing unit moves towards the flexible membrane 2 . It can be seen that it is only necessary for the pressure applying unit 17 to have a flat-shaped pressing mechanism to form the curved surface in FIG. 2 . After the forming is completed, the pressure applying unit 17 drives the pressurizing mechanism to return, and then the hydraulic container 1 is filled with liquid, the flexible diaphragm 2 rises, and the pressed sheet is taken out.

Preferably, the hydraulic container 1 is provided with a clamping groove for clamping the plate 5 to be formed.

Preferably, the plate flexible multi-point forming device further includes a blank holder 11, and the flexible diaphragm 2 is sealedly connected with the hydraulic container 1 through the blank holder 11.

Preferably, the bracket 8 includes a base 18 on which the hydraulic container 1 is formed, and an oil passage is arranged in the base 18, and the hydraulic container 1 is connected to the pressure regulating unit through the oil passage.

Preferably, the plate flexible multi-point forming device further includes a limit support 4 installed on the support 8, which is used to limit the stroke of the pressurizing unit.

The present invention adopts the flexible diaphragm 2 to realize the support and normal restraint of the plate 5 to be formed, the forming curved surface can be formed arbitrarily and the adjustment method is simple, and the density of the pressurizing unit is not limited, the forming precision is high and the sealing is reliable. It is no longer necessary to adjust any components in real time during the forming process. For sheets of different materials, thicknesses and target shapes, the flexible diaphragm 2 can provide matching real-time adjustable and uniform normal force. Effective normal constraints are formed, and the suspended area in the forming process of the curved stamping parts is basically eliminated, which can effectively suppress the wrinkling of the sheet metal, and effectively suppress the wrinkling and springback. The formed workpiece has good surface quality, uniform thickness and no defects such as indentation. The device has reasonable structure, simple operation and use, low manufacturing cost and reliable operation.

In addition, the present invention does not require an edge-pressing device, omits the trimming process after forming, improves the utilization rate of the sheet material, and has good product quality, uniform thickness, and well-guaranteed surface quality.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (8)

1. A flexible multi-point forming device for sheet material, characterized in that it comprises: a hydraulic container (1), said hydraulic container (1) having an opening; A flexible diaphragm (2), installed at the opening, the flexible diaphragm (2) seals the interior of the hydraulic container (1) to form a hydraulic cavity (3); a pressure regulating unit, communicated with the hydraulic chamber (3); A plurality of pressurizing units are movably arranged relative to the flexible diaphragm (2); The plurality of pressing units move toward the direction of the flexible membrane (2), so that the plate to be formed (5) arranged between the flexible membrane (2) and the pressing unit moves along with the The flexible diaphragm (2) deforms synchronously into the deformation of the hydraulic chamber (3), until the plate to be formed (5) forms a predetermined shape; When in use, first place the plate to be formed (5) on the outside of the flexible diaphragm (2), then drive the pressurizing unit to move in the direction of the flexible diaphragm (2), when one end of the pressurizing unit pushes the flexible diaphragm (2 ) to the inside of the hydraulic container (1), while pushing the plate to be formed (5) clamped between the flexible diaphragm (2) and the pressurizing unit, the same deformation will occur as the flexible diaphragm (2) , in this process, there are multiple contact points between multiple pressurized units and the sheet to be formed (5), and at the same time, due to the nature of hydraulic transmission, the liquid in the hydraulic container (1) passes through the flexible diaphragm (2) A uniform normal force is provided to the entire surface of the plate (5) to be formed to form a normal constraint on the plate (5) to be formed. 2. The sheet material flexible multi-point forming device according to claim 1, characterized in that, the pressurizing unit comprises a pressing rod (6) and an elastic element (7); The sheet material flexible multi-point forming device also includes a bracket (8), and a plurality of installation holes are opened on the bracket (8), and each of the pressurizing units is arranged at the installation holes in a one-to-one correspondence; Wherein, the pressure rod (6) is movably installed in the installation hole, the elastic element (7) is sleeved on the outside of the pressure rod (6), and one end of the elastic element (7) is connected to the The bracket (8) abuts, and the other end abuts against the pressing rod (6). 3. The sheet material flexible multi-point forming device according to claim 2, characterized in that, the pressurizing unit further comprises a pressure head (9), and the proximity between the pressure head (9) and the pressure rod (6) One end of the flexible diaphragm (2) is pivotably connected. 4. The sheet material flexible multi-point forming device according to claim 3, characterized in that, the press head (9) is pivotably connected to the one end of the press rod (6) by means of magnetic adsorption. 5. The sheet material flexible multi-point forming device according to claim 2, characterized in that, the pressurizing unit also includes an adjustment device installed at the end of the pressing rod (6) away from the flexible diaphragm (2). Bolts (10). 6. The sheet material flexible multi-point forming device according to claim 2, characterized in that, the sheet material flexible multi-point forming device further comprises a pressure applying unit (17), and the pressure applying unit (17) is arranged on the press The side of the rod (6) away from the flexible membrane (2) is used to drive the plurality of pressurizing units to move towards the flexible membrane (2). 7. The flexible multi-point forming device for sheet material according to claim 1, characterized in that, the hydraulic container (1) is provided with a clamping groove for clamping the sheet material (5) to be formed. 8. The sheet material flexible multi-point forming device according to claim 1, characterized in that, the sheet material flexible multi-point forming device further comprises a blank holder (11), and the flexible diaphragm (2) passes through the blank holder The ring (11) is sealingly connected with said hydraulic container (1).