Stamping die system with adjustable blank holder force and control method thereof

Abstract

The invention relates to the technical field of stamping forming, particularly provides a stamping die system with adjustable blank holder force and a control method thereof, and aims to solve the problem that the blank holder force in an existing stamping drawing die is difficult to accurately control, so that the product quality is unstable. In order to achieve the purpose, the stamping die system with the adjustable blank holder force comprises an upper die and a lower die which are oppositely arranged up and down; the blank holder is arranged in the lower die; the balance block assembly is arranged on the face, opposite to the upper die, of the blank holder and used for collecting the real-time blank holder force value applied to the blank holder and adjusting the local blank holder force applied to the blank holder; the pressing machine is connected with the upper die and the blank holder and used for driving the upper die and the blank holder and adjusting the overall blank holder force acting on the blank holder; and the control system is connected with the pressing machine and the balance block assembly. According to the system, the blank holder force on the blank holder in the stamping die can be accurately and adaptively adjusted in real time, and the stability and precision of the stamping process are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of stamping and forming, and in particular to a stamping die system with adjustable blanking force and a control method thereof. Background Art

[0002] During the cold stamping process, controlling the blank holder force plays a critical role in the quality of the stamped part. If the blank holder force applied to the sheet metal is too low, it will wrinkle during the stamping process, affecting the dimensional accuracy and surface quality of the stamped part. Excessive blank holder force can cause the sheet metal to crack, resulting in scrap. The balance block installed on the drawing die plays an important role in regulating the blank holder force applied to the sheet metal.

[0003] Traditional methods for adjusting the blank holder force of stamping dies are often based on experience and cannot be adjusted in real time according to the actual conditions of the stamping process. In actual production, due to factors such as the material properties and thickness tolerances of the sheet metal, and fluctuations in stamping process parameters, a fixed preset blank holder force cannot guarantee high-quality stamping parts under various working conditions. It is necessary to frequently observe changes in sheet metal inflow and adjust the balancing block accordingly to ensure part quality.

[0004] In addition, after the stamping die is manufactured in the die factory and debugged to a stable state, it is sent back to the stamping workshop of the main engine manufacturer. Due to the differences in the presses, the inflow of sheet metal is often found to have changed when it is first put online. This is also due to the differences in the presses causing changes in the clamping force in different areas. In order to quickly adjust to the stable state before sending the die, it is necessary to manually adjust the gasket of the balance block multiple times, and press the parts to observe the inflow of the parts, resulting in a large amount of debugging resources wasted.

[0005] It can be seen that although the existing manual adjustment method can make adjustments to a certain extent, its response speed is slow and cannot meet the needs of high-speed stamping production. Summary of the Invention

[0006] The present invention aims to solve the above technical problems, that is, to solve the problem that the blank holding force in the existing stamping and drawing dies is difficult to accurately control, resulting in unstable product quality and limited production efficiency.

[0007] In the first aspect, the present invention provides a stamping die system with adjustable blank holding force, comprising: an upper die and a lower die arranged opposite to each other in the upper and lower directions; a blank holding ring arranged in the lower die; a balancing block assembly arranged on the surface of the blank holding ring opposite to the upper die, for collecting the real-time blank holding force value applied to the blank holding ring and adjusting the local blank holding force applied to the blank holding ring; a press connected to the upper die and the blank holding ring, for driving the upper die and the blank holding ring and adjusting the overall blank holding force applied to the blank holding ring; a control system connected to the press and the balancing block assembly, for controlling the press and the balancing block assembly and obtaining the real-time blank holding force value collected by the balancing block assembly.

[0008] Furthermore, the balancing block assembly includes: an adjusting balancing block, which is arranged on the surface of the pressure ring opposite to the upper mold; a pressure detection module, which is arranged in the adjusting balancing block and connected to the control system, for collecting the real-time pressure force value applied to the adjusting balancing block; a lifting device, which is arranged at the bottom of the adjusting balancing block and connected to the control system, for lifting and lowering the adjusting balancing block.

[0009] Furthermore, the control system includes a control module and an intelligent decision-making module; the control module is connected to the pressure detection module and the intelligent decision-making module, and is used to obtain the real-time clamping force value collected by the pressure detection module and send it to the intelligent decision-making module; the intelligent decision-making module is connected to the control module, and is used to generate control instructions based on the acquired real-time clamping force value and send them to the control module; the control module is also connected to the press and the lifting device, and is used to control the press and the lifting device according to the control instructions issued by the intelligent decision module.

[0010] Furthermore, the intelligent decision-making module is connected to the pressure detection module and is provided with a display module for displaying the real-time blank holding force value collected by the pressure detection module.

[0011] In the second aspect, the present invention also provides a control method for a stamping die system with adjustable blanking force, which is applied to the stamping die system with adjustable blanking force as described above, and the control method includes the following steps: when the upper die presses the sheet material against the lower die and presses it into contact with the blanking ring, the pressure detection module collects the real-time blanking force value applied to the adjustment balance block and sends it to the intelligent decision-making module via the control module; the intelligent decision-making module generates a control instruction based on the acquired real-time blanking force value and sends it to the control module; the control module drives the press and lifting device according to the control instruction to adjust the blanking force applied to the blanking ring.

[0012] Furthermore, before the intelligent decision-making module generates a control instruction based on the acquired real-time blank holding force value and sends it to the control module, it also includes: setting a corresponding standard pressure value for each balancing block component and uploading the standard pressure value to the intelligent decision-making module.

[0013] Furthermore, the step in which the intelligent decision-making module generates a control instruction based on the acquired real-time blank holding force value and sends it to the control module includes: comparing the real-time blank holding force value or / and its sum collected by the pressure detection module in each of the balancing block components with the corresponding set value, and determining whether the blank holding force needs to be adjusted based on the comparison result; when it is determined that the blank holding force needs to be adjusted, formulating an adjustment rule based on the comparison result, and sending the adjustment rule to the control module.

[0014] Furthermore, the step of comparing the real-time blank holding force value or / and its sum collected by the pressure detection module in each of the balancing block assemblies with the corresponding set value, and determining whether the blank holding force needs to be adjusted based on the comparison result includes: calculating whether the difference between the sum of the real-time blank holding force values collected by each of the pressure detection modules and the preset total pressure value is greater than a first preset value; if it is greater than the first preset value, determining that the overall blank holding force needs to be adjusted; or / and, calculating whether the difference between the real-time blank holding force value collected by each of the pressure detection modules and the corresponding standard pressure value is greater than a second preset value; if it is greater than the second preset value, determining that the local blank holding force needs to be adjusted.

[0015] Furthermore, when it is determined that the blank holding force needs to be adjusted, an adjustment rule is formulated based on the comparison result, and the step of sending the adjustment rule to the control module includes: when the difference between the sum of the real-time blank holding force values and the preset total pressure value is greater than the first preset value, based on the difference, an adjustment rule is formulated for adjusting the overall blank holding force acting on the blank holding ring through the press; or / and, when the difference between the real-time blank holding force value collected by one or part of the pressure detection modules and the corresponding standard pressure value is greater than the second preset value, based on the difference, an adjustment rule is formulated for adjusting the local blank holding force acting on the blank holding ring by adjusting the height of the adjustment balance block in the balance block assembly 40 to which the pressure detection module belongs.

[0016] Furthermore, the control module also includes an alarm device, and the control method also includes: when the difference between the sum of the real-time clamping force values and the preset total pressure value is greater than the preset value, or when the difference between the real-time clamping force values collected by one or part of the pressure detection modules and the corresponding standard pressure values is greater than the preset value, the intelligent decision-making module sends an alarm instruction to the control module to control the alarm device to issue an alarm.

[0017] When the above-mentioned technical solution is adopted, the present invention can monitor the changes in the blank holder force during the stamping and drawing process in real time by installing a balancing block assembly on the blank holder ring of the stamping die, analyze the blank holder force fed back in real time, and quickly and accurately formulate blank holder force adjustment rules to automatically adjust the blank holder force. The system and its control method effectively improve the stability and accuracy of the stamping process, reduce defects such as wrinkling, cracking, and dimensional instability of the material caused by abnormal changes in the blank holder force, and improve the quality stability of the stamped parts. Ultimately, it solves the technical problem that the blank holder force in traditional stamping and drawing dies is difficult to accurately control, resulting in unstable product quality and limited production efficiency.

[0018] By utilizing advanced sensor technology and data processing algorithms, this stamping die system boasts a high response speed, meeting the demands of high-speed stamping production and improving production efficiency. The system is highly versatile and can be flexibly configured and adjusted to suit different stamping dies and stamping process requirements, adapting to a variety of production scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 Schematic diagram of the structure of a stamping die system with adjustable blank holding force in an embodiment of the present application;

[0021] Figure 2 A diagram showing the data interaction relationship between the control system and various components of the stamping die system with adjustable blank holding force in an embodiment of the present application;

[0022] Figure 3 This is a process flow chart of a control method for a stamping die system with adjustable blank holding force in an embodiment of the present application;

[0023] Figure 4 This is a flow chart of step S200 in the control method of the stamping die system with adjustable blank holding force in an embodiment of the present application.

[0024] Reference numerals:

[0025] 10. Upper die; 20. Lower die; 30. Blank holder; 40. Balance block assembly; 50. Sheet metal. DETAILED DESCRIPTION

[0026] Preferred embodiments of the present invention are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely intended to illustrate the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art may adjust these embodiments as needed to suit specific applications.

[0027] First, it should be noted that in the description of the present invention, terms such as "upper," "lower," "left," "right," "vertical," "horizontal," "longitudinal," "inner," and "outer" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or component described must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0029] Traditional methods for adjusting the blank holder force of stamping dies are often based on experience and cannot be adjusted in real time according to the actual conditions of the stamping process. In actual production, due to factors such as the material properties and thickness tolerances of the sheet metal, and fluctuations in stamping process parameters, a fixed preset blank holder force cannot guarantee high-quality stamping parts under various working conditions. It is necessary to frequently observe changes in sheet metal inflow and adjust the balancing block accordingly to ensure part quality.

[0030] In addition, after the stamping die is manufactured in the die factory and debugged to a stable state, it is sent back to the stamping workshop of the main engine manufacturer. Due to the differences in the presses, the inflow of sheet metal is often found to have changed when it is first put online. This is also due to the differences in the presses causing changes in the clamping force in different areas. In order to quickly adjust to the stable state before sending the die, it is necessary to manually adjust the gasket of the balance block multiple times, and press the parts to observe the inflow of the parts, resulting in a large amount of debugging resources wasted.

[0031] like Figure 1As shown, the embodiment of the present application provides a stamping die system with adjustable blanking force, which can monitor the changes in the blanking force during the stamping and drawing process in real time and automatically adjust the blanking force based on the real-time feedback of the blanking force. The stamping die system includes: an upper die 10 and a lower die 20 arranged in an upper and lower relative manner, a blank holder 30, a balancing block assembly 40, a press (not shown in the figure), and a control system (not shown in the figure).

[0032] The upper die 10 is usually a concave die, and the lower die 20 is usually a convex die. The blank holder 30 is arranged in the lower die 20, and the balance block assembly 40 is arranged on the surface of the blank holder 30 opposite to the upper die 10 (that is, on the upper surface of the blank holder 30), and is used to collect the real-time blank holder force value applied to the blank holder 30 and adjust the local blank holder force applied to the blank holder 30. Usually, a plurality of balance block assemblies 40 are arranged on the upper surface of the blank holder 30. The press is connected to the upper die 10 and the blank holder 30, and is used to drive the upper die 10 and the blank holder 30 and adjust the overall blank holder force applied to the blank holder 30. The control system is connected to the press and the balance block assembly 40, and is used to control the press and the balance block assembly 40 and obtain the real-time blank holder force value collected by the balance block assembly 40.

[0033] In the stamping die system in the embodiment of the present application, before the sheet material 50 is stamped, the upper die 10 and the lower die 20 are in a separated state. When the sheet material 50 is stamped, the blank holder 30 is driven by the press to rise from the lower die 20 to a position where the upper surface of the blank holder 30 is higher than the highest point of the molding surface of the lower die 20. The sheet material 50 is then placed on the blank holder 30. Next, the press presses the upper die 10 downward so that the upper die 10 presses the sheet material 50 and the blank holder 30 together. Finally, the upper die 10 and the lower die 20 are closed, and the sheet material 50 is pressed on the lower die 20 to form a stamped component. The area at the edge of the sheet material 50 is clamped between the edge of the upper die 10 and the blank holder 30, and the balance block assembly 40 provided on the upper surface of the blank holder 30 abuts against the upper die 10.

[0034] During the stamping process, the press applies an upward force to the blank holder 30 from below, causing the blank holder 30 to abut against the upper die 10 and clamping the edge of the sheet 50 between the blank holder 30 and the upper die 10. The interaction force between the blank holder 30 and the upper die 10 is the blank holder force. The balance weight assembly 40 provided on the upper surface of the blank holder 30 can detect and collect the blank holder force applied to the blank holder 30.

[0035] Furthermore, the balancing weight assembly 40 includes an adjusting balancing weight, a pressure detection module, and a lifting device (all not shown in the figure). The adjusting balancing weight is arranged on the surface of the blank holder 30 opposite to the upper die 10, and the adjusting balancing weight is generally a cylindrical structure. The pressure detection module is arranged inside the adjusting balancing weight and is connected to the control system to collect the real-time blank holder force value applied to the adjusting balancing weight. The lifting device is arranged at the bottom of the adjusting balancing weight and is connected to the control system. The lifting device can lift and lower the adjusting balancing weight under the drive of the control module.

[0036] When the upper die 10 and the lower die 20 are closed, the blank holder 30 abuts against the upper die 10, so that the upper die 10 presses the edge area of the sheet material 50 that forms the stamping part tightly against the blank holder 30. At the same time, the upper die 10 also abuts against the adjustment balance block in the balance block assembly 40. The sum of the pressure values collected by the pressure detection modules in all the adjustment balance blocks set on the blank holder 30 is equal to the overall blank holding force applied to the blank holder 30. The pressure value collected by the pressure detection module in a single adjustment balance block is the local blank holding force applied to the area of the blank holder 30 adjacent to the adjustment balance block. By adjusting the force applied by the press on the blank holder 30, the overall blank holding force on the blank holder 30 can be adjusted. By adjusting the height of the adjustment balance block in the balance block assembly 40 set on the upper surface of the blank holder 30, the local blank holding force of the area of the blank holder 30 adjacent to the balance block can be adjusted.

[0037] The balancing weight assembly 40 is an independent hardware module formed by integrating the adjusting balancing weight, the pressure detection module, and the lifting device. A set number of balancing weight assemblies 40 can be flexibly arranged at set positions on the blank holder 30 as needed. The pressure detection module can adopt a high-precision, high-response speed model to ensure the accuracy and timeliness of the real-time blank holder force value it collects.

[0038] Further, if Figure 2 As shown, the control system includes a control module and an intelligent decision module.

[0039] The control module is connected to the pressure detection module for obtaining the real-time blank holding force value collected by the pressure detection module; and the control module is also connected to the intelligent decision module for sending the real-time blank holding force value collected by the pressure detection module to the intelligent decision module.

[0040] The intelligent decision-making module can generate control instructions based on the acquired real-time blank holder force values and send them to the control module. The control module is also connected to the lifting devices in the press and the balancing block assembly 40, and is used to control the lifting devices in the press and each balancing block assembly 40 according to the control instructions issued by the intelligent decision-making module, thereby accurately and timely adjusting the blank holder force value on the blank holder ring 30 according to the real-time blank holder force value. By controlling the press, the force applied by the press to the blank holder ring 30 can be adjusted, thereby adjusting the overall blank holder force applied to the blank holder ring 30; by controlling the lifting devices in each balancing block assembly 40 to adjust the height of the balancing block, the local blank holder force exerted on a local area of the blank holder ring 30 can be adjusted.

[0041] Furthermore, the intelligent decision module is also connected to the pressure detection module, and a display module is also provided in the intelligent decision module for displaying the real-time blank holding force value collected by the pressure detection module.

[0042] like Figure 3 As shown, an embodiment of the present application further provides a control method for a stamping die system with adjustable blanking force, which is applied to the stamping die system with adjustable blanking force as described above. The control method includes the following steps:

[0043] Step S100: When the upper die 10 presses the sheet 50 against the lower die 20 and presses it into contact with the blank holder 30, the pressure detection module collects the real-time blank holder force value applied to the adjustment balance block and sends it to the intelligent decision module via the control module.

[0044] When the upper die 10 presses the edge of the sheet 50 against the blank holder 30, the adjustment balance block provided on the upper surface of the blank holder 30 also comes into contact with the upper die 10 and is subjected to the same blank holding force as the blank holder 30. The pressure detection module provided in the adjustment balance block collects the real-time blank holding force value applied to the adjustment balance block and sends the collected real-time blank holding force value to the control module, which then sends it to the intelligent decision module.

[0045] Step S200: The intelligent decision module generates a control instruction based on the acquired real-time blank holder force value and sends it to the control module.

[0046] Furthermore, before step S200, the following steps are also included:

[0047] Step S110: setting a corresponding standard pressure value for each balancing weight assembly 40, and uploading the standard pressure value to the intelligent decision module.

[0048] During the design process of the stamping die system, the number and arrangement (e.g., position, distance between each other, etc.) of the balancing block assemblies 40 set on the blank holder 30 will be determined based on the shape, material, thickness and other characteristics of the part to be stamped. After the stamping die system is manufactured and debugged, the stable pressure value borne by the adjustment balancing block in each balancing block assembly 40 set on the blank holder 30 will be recorded separately, and the stable pressure value will be used as the standard value of the pressure detection module in the balancing block assembly 40 at that position; this information will also be uploaded to the intelligent decision-making system. The standard pressure value of the adjustment balancing block in each balancing block assembly 40 can be the same or different, and it should be determined according to the specific situation of the stamping part.

[0049] like Figure 4 As shown, step S200 further includes the following steps:

[0050] Step S210: comparing the real-time blank holder force value or / and its sum collected by the pressure detection module in each balancing weight assembly 40 with the corresponding set value, and determining whether the blank holder force needs to be adjusted based on the comparison result.

[0051] Furthermore, step S210 includes:

[0052] Calculating whether the difference between the sum of the real-time blank holder force values collected by each pressure detection module and the preset total pressure value is greater than a first preset value, and if so, determining that the overall blank holder force needs to be adjusted; or / and,

[0053] Calculate whether the difference between the real-time blank holding force value collected by each pressure detection module and its corresponding standard pressure value is greater than a second preset value. If it is greater than the second preset value, determine that the local blank holding force needs to be adjusted.

[0054] Specifically,

[0055] When the difference between the sum of the real-time blank holding force values collected by each pressure detection module and the preset total pressure value is greater than a first preset value is used as a judgment criterion;

[0056] On the one hand, the absolute value of the difference between the sum of the real-time blank holder force values collected by each pressure detection module and the preset total pressure value can be compared with the first preset value. In this case, the first preset value is a numerical value.

[0057] If the absolute value of the difference between the sum of the real-time blank holder force values and the preset total pressure value is greater than the first preset value, it is determined that the real-time blank holder force value exceeds the standard and the blank holder force needs to be adjusted. There are two cases:

[0058] The first case is when the sum of the real-time blank holder force values is less than the preset total pressure value, and the absolute value of the difference between the two is greater than the first preset value. This indicates that the overall blank holder force acting on the blank holder 30 is too small and needs to be increased by increasing the force applied by the press to the blank holder 30.

[0059] The second case is when the sum of the real-time blank holder force values is greater than the preset total pressure value, and the absolute value of the difference between the two is greater than the first preset value. This indicates that the overall blank holder force acting on the blank holder 30 is too large and needs to be reduced by reducing the force applied by the press to the blank holder 30.

[0060] On the other hand, the absolute value of the difference between the sum of the real-time blank holding force values and the preset total pressure value as a percentage of the preset total pressure value can also be compared with the first preset value. In this case, the first preset value is a percentage value.

[0061] If the absolute value of the difference between the sum of the real-time blank holder force values and the preset total pressure value as a percentage of the preset total pressure value is greater than the percentage of the first preset value, it is determined that the sum of the real-time blank holder force values exceeds the standard and the blank holder force needs to be adjusted. There are still two situations here:

[0062] The first case is when the sum of the real-time blank holder force values is less than the preset total pressure value, and the absolute value of the difference between the two as a percentage of the preset total pressure value is greater than the percentage of the first preset value. This indicates that the overall blank holder force acting on the blank holder 30 is too low and needs to be increased by increasing the force applied by the press to the blank holder 30.

[0063] The second case is when the sum of the real-time blank holder force values is greater than the preset total pressure value, and the absolute value of the difference between the two as a percentage of the preset total pressure value is greater than the percentage of the first preset value. This indicates that the overall blank holder force acting on the blank holder 30 is too large and needs to be reduced by reducing the force applied by the press to the blank holder 30.

[0064] When the difference between the real-time blank holding force value collected by each pressure detection module and the corresponding standard pressure value is greater than a second preset value, the judgment criterion is used;

[0065] On the one hand, the absolute value of the difference between the real-time blank holder force value collected by each pressure detection module and its corresponding standard pressure value can be compared with the second preset value. In this case, the second preset value is a numerical value.

[0066] If the absolute value of the difference between the real-time blank holder force value collected by one or more pressure detection modules and the corresponding standard pressure value is greater than a preset threshold, it is determined that the real-time blank holder force value collected by these pressure detection modules exceeds the standard, and the blank holder force at the position of the balance block assembly 40 to which these pressure detection modules belong needs to be adjusted. There are two situations here:

[0067] The first scenario is when the real-time blank holder force value collected by the pressure detection module is less than the corresponding standard pressure value, and the absolute value of the difference between the two is greater than a second preset value. This indicates that the local blank holder force applied to the blank holder ring 30 at the location of the balancing weight assembly 40 of the pressure detection module is too low, and the local blank holder force applied to the blank holder ring 30 at this location needs to be increased by adjusting the height of the balancing weight.

[0068] The second scenario is when the real-time blank holder force value collected by the pressure detection module is greater than its corresponding standard pressure value, and the absolute value of the difference between the two is greater than a second preset value. This indicates that the local blank holder force applied to the blank holder ring 30 at the location of the balancing weight assembly 40 to which the pressure detection module belongs is too large, and the local blank holder force applied to the blank holder ring 30 at this location needs to be reduced by adjusting the height of the balancing weight.

[0069] On the other hand, the absolute value of the difference between the real-time blank holder force value collected by each pressure detection module and its corresponding standard pressure value as a percentage of the corresponding standard pressure value can also be compared with the second preset value. In this case, the second preset value is a percentage value.

[0070] If the absolute value of the difference between the real-time blank holder force value collected by one or more pressure detection modules and the corresponding standard pressure value accounts for a percentage greater than the percentage of the corresponding standard pressure value by a second preset value, it is determined that the real-time blank holder force value collected by these pressure detection modules exceeds the standard, and the blank holder force at the position where the balance block assembly 40 to which these pressure detection modules belong needs to be adjusted. There are two situations here:

[0071] The first scenario is that the real-time blank holder force value collected by the pressure detection module is less than the corresponding standard pressure value, and the absolute value of the difference between the two as a percentage of the corresponding standard pressure value is greater than the percentage of the second preset value. This indicates that the local blank holder force applied to the blank holder ring 30 at the location of the balancing weight assembly 40 of the pressure detection module is too low, and the local blank holder force applied to the blank holder ring 30 at this location needs to be increased by adjusting the height of the balancing weight.

[0072] The second scenario is that the real-time blank holder force value collected by the pressure detection module is greater than the corresponding standard pressure value, and the absolute value of the difference between the two as a percentage of the corresponding standard pressure value is greater than the percentage of the second preset value. This indicates that the local blank holder force applied to the blank holder ring 30 at the location of the balancing weight assembly 40 to which the pressure detection module belongs is too large, and the local blank holder force applied to the blank holder ring 30 at this location needs to be reduced by adjusting the height of the balancing weight.

[0073] Step S220: When it is determined that the blank holder force needs to be adjusted, an adjustment rule is formulated according to the comparison result, and the adjustment rule is sent to the control module.

[0074] Furthermore, step S220 includes:

[0075] When the difference between the sum of the real-time blank holding force values and the preset total pressure value is greater than a first preset value, formulating an adjustment rule for adjusting the overall blank holding force acting on the blank holding ring 30 by the press according to the difference; or / and,

[0076] When the difference between the real-time blank holding force value collected by one or part of the pressure detection modules and its corresponding standard pressure value is greater than a second preset value, an adjustment rule is formulated based on the difference to adjust the local blank holding force acting on the blank holding ring 30 by adjusting the height of the adjustment balance block in the balance block assembly 40 belonging to the pressure detection module.

[0077] Specifically,

[0078] When the criterion for determining whether the blank holder force needs to be adjusted is whether the absolute value of the difference between the sum of the real-time blank holder force values collected by each pressure detection module and the preset total pressure value accounts for a percentage of the preset total pressure value that is greater than a first preset value, in a specific embodiment, the percentage of the first preset value can be set to 5%. When the absolute value of the difference between the sum of the real-time blank holder force values and the preset total pressure value accounts for a percentage of the preset total pressure value that is greater than 5%, the intelligent decision module determines that the overall blank holder force acting on the blank holder ring 30 needs to be adjusted, and it is necessary to formulate an adjustment rule for adjusting the overall blank holder force acting on the blank holder ring 30 through the press.

[0079] When formulating the adjustment rules, the intelligent decision-making module will calculate the current value (greater than 5%) of the absolute value of the difference between the sum of the real-time blank holding force values and the preset total pressure value as a percentage of the preset total pressure value, and calculate the value by which the force applied by the press to the blank holding ring 30 needs to be lowered from the current pressure value when the percentage value is reduced to within 5%, and generate a control instruction accordingly and send it to the control module. In actual applications, the target value for the final adjustment of the above percentage value can also be determined based on experience or factors such as the shape and size of the parts to be stamped, the material and thickness of the sheet material 50, for example, 4.5% or 4%. The embodiments of the present application do not make specific restrictions on this.

[0080] When the absolute value of the difference between the sum of the real-time blank holder force values collected by each pressure detection module and the preset total pressure value is greater than a first preset value as the criterion for determining whether the blank holder force needs to be adjusted, the principle and method of the intelligent decision-making module to formulate the adjustment rules are the same as the principle in the above example. The only difference is that the adjustment target is changed from the percentage of the absolute value of the difference between the sum of the real-time blank holder force values collected by each pressure detection module and the preset total pressure value to the absolute value of the difference between the sum of the real-time blank holder force values collected by each pressure detection module and the preset total pressure value. The details are not repeated here.

[0081] When the absolute value of the difference between the real-time blank holding force value collected by one or more pressure detection modules and its corresponding standard pressure value accounts for a percentage greater than a second preset value as a criterion for determining whether the blank holding force needs to be adjusted, in a specific embodiment, the percentage of the second preset value can be set to 5%. When the absolute value of the difference between the real-time blank holding force value collected by any pressure detection module and its corresponding standard pressure value accounts for a percentage greater than 5% of the corresponding standard pressure value, the intelligent decision module determines that the local blank holding force at the position of the blank holding ring 30 where the balance block assembly 40 corresponding to the pressure detection module is located needs to be adjusted, and formulates an adjustment rule for adjusting the local blank holding force acting on the blank holding ring 30 by adjusting the height of the adjustment balance block in the balance block assembly 40 to which the pressure detection module belongs.

[0082] When formulating the adjustment rules, the intelligent decision-making module will calculate the current value (greater than 5%) of the percentage of the absolute value of the difference between the real-time blank holding force value collected by the above-mentioned pressure detection module and the corresponding standard pressure value to the corresponding standard pressure value, and calculate the value of the blank holding force value to be borne by the adjustment balance block in the balance block assembly 40 when the percentage value is reduced to within 5%. It can also calculate the height value that the adjustment balance block in the balance block assembly 40 needs to rise or fall, and generate a control instruction based on this, and send it to the control module. After receiving the control instruction, the control module drives the lifting device to adjust the height of the above-mentioned adjustment balance block accordingly. In actual applications, the target value of the final adjustment of the above-mentioned percentage value can be determined based on experience or factors such as the shape and size of the stamped part, the material and thickness of the sheet material 50, for example, 4.5% or 4%. The embodiments of the present application do not make specific restrictions on this.

[0083] Furthermore, when the real-time blank holding force value collected by the pressure detection module in a certain balancing block assembly 40 is less than its corresponding standard pressure value, the intelligent decision module determines that the local blank holding force of the blank holding ring area corresponding to the balancing block assembly 40 is too small, and sends a control instruction to the control module to increase the height of the adjusting balancing block in the balancing block assembly 40, so as to increase the local blank holding force at that location. After receiving the control instruction, the control module drives the lifting device to raise the adjusting balancing block to a corresponding height. Correspondingly, when the real-time blank holding force value collected by the pressure detection module in a certain balancing block assembly 40 is greater than its corresponding standard pressure value, the intelligent decision module determines that the local blank holding force of the blank holding ring area corresponding to the balancing block assembly 40 is too large, and sends a control instruction to the control module to lower the height of the adjusting balancing block in the balancing block assembly 40, so as to reduce the local blank holding force at that location. After receiving the control instruction, the control module drives the lifting device to lower the adjusting balancing block to a corresponding height.

[0084] When the absolute value of the difference between the real-time blank holder force value collected by one or several pressure detection modules and the corresponding standard pressure value is greater than a second preset value as the criterion for determining whether the blank holder force needs to be adjusted, the principle and method of the intelligent decision-making module to formulate the adjustment rules are the same as the principle in the above example. The only difference is that the adjustment target is changed from the percentage of the absolute value of the difference between the real-time blank holder force value collected by one or several pressure detection modules and the corresponding standard pressure value to the corresponding standard pressure value to the absolute value of the difference between the real-time blank holder force value collected by these pressure detection modules and the corresponding standard pressure value. The details are not repeated here.

[0085] Furthermore, when adjusting the height of the adjusting balance block in the balance block assembly 40 to adjust the local blank holding force at the position of the blank holding ring 30 where the balance block assembly 40 is located, the adjustment rule formulated by the intelligent decision module can be to determine only the adjustment direction (increase or decrease) of the adjusting balance block in the balance block assembly 40 based on the comparison result of the real-time blank holding force value collected by the pressure detection module in the balance block assembly 40 to be adjusted and its corresponding standard pressure value, but not to calculate the height value of the balance block raised or lowered, and set the adjusting balance block to gradually adjust the height of the adjusting balance block according to the set unit height (for example, adjusting the height by 0.01 mm each time), and determine whether the local blank holding force value meets the requirement based on the real-time blank holding force value collected by the pressure detection module after each height adjustment (using the determination method described above). The height adjustment of the adjusting balance block is stopped until the local blank holding force value at that location meets the requirement. The intelligent decision module generates corresponding control instructions based on the above statement and sends them to the control module.

[0086] Step S300 : The control module drives the press and the lifting device according to the control instruction to adjust the blank holding force applied to the blank holding ring 30 .

[0087] When the overall blank holding force acting on the blank holding ring 30 needs to be adjusted, the control module sends a command to the press to control the press to adjust the force it applies to the blank holding ring 30 so that the overall blank holding force acting on the blank holding ring 30 returns to a normal range. A hydraulic cylinder can be set at the bottom of the blank holding ring 30 to provide the blank holding force for the blank holding ring 30.

[0088] When it is necessary to adjust the local blank holding force at the position where some of the balancing block assemblies 40 are located, the control module sends an instruction to the lifting device, which adjusts the height of the adjusting balancing blocks in these balancing block assemblies 40 through the lifting device to adjust the local blank holding force acting on the blank holding ring 30 at the position where these balancing block assemblies 40 are located, so that the local blank holding force is restored to the normal range.

[0089] Furthermore, the control module also includes an alarm device. When the difference between the sum of the real-time blank holder force values and the preset total pressure value is greater than a preset value, or when the difference between the real-time blank holder force values collected by one or some of the pressure detection modules and their corresponding standard pressure values is greater than a preset value, the intelligent decision module sends an alarm instruction to the control module, controlling the alarm device to sound an alarm.

[0090] An audible and visual alarm device can be installed on the control module to sound or illuminate an alarm. Alternatively, the alarm device can be installed on the lower mold 20 and connected to the control module. When the control module receives the alarm instruction sent by the intelligent decision module, the alarm device is controlled to sound an alarm.

[0091] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A stamping die system with adjustable blank holding force, characterized in that: include: An upper mold (10) and a lower mold (20) are arranged opposite to each other; A blank holder (30) is provided in the lower die (20); a balancing block assembly (40), which is arranged on the surface of the blank holder (30) opposite to the upper die (10), and is used to collect the real-time blank holder force value applied to the blank holder (30) and adjust the local blank holder force applied to the blank holder (30); A press, connected to the upper die (10) and the blank holder (30), for driving the upper die (10) and the blank holder (30) and adjusting the overall blank holder force acting on the blank holder (30); A control system is connected to the press and the balancing weight assembly (40) and is used to control the press and the balancing weight assembly (40) and obtain the real-time blank holding force value collected by the balancing weight assembly (40).

2. The stamping die system according to claim 1, characterized in that: The balancing weight assembly (40) includes: An adjusting balance block is provided on a surface of the blank holder (30) opposite to the upper die (10); a pressure detection module, which is disposed in the adjusting balance block and connected to the control system, and is used to collect a real-time blank holding force value applied to the adjusting balance block; A lifting device is arranged at the bottom of the adjusting balance block and is connected to the control system, and is used for lifting and lowering the adjusting balance block.

3. The stamping die system according to claim 2, characterized in that: The control system includes a control module and an intelligent decision-making module; The control module is connected to the pressure detection module and the intelligent decision module, and is used to obtain the real-time blank holder force value collected by the pressure detection module and send it to the intelligent decision module; The intelligent decision module is connected to the control module and is used to generate a control instruction according to the acquired real-time blank holder force value and send it to the control module; The control module is also connected to the press and the lifting device, and is used to control the press and the lifting device according to the control instructions issued by the intelligent decision module.

4. The stamping die system according to claim 3, characterized in that: The intelligent decision-making module is connected to the pressure detection module and is provided with a display module for displaying the real-time blank holding force value collected by the pressure detection module.

5. A control method for a stamping die system with adjustable blanking force, applied to the stamping die system with adjustable blanking force as claimed in claim 4, characterized in that: The control method comprises the following steps: When the upper die (10) presses the sheet material (50) against the lower die (20) and is pressed into contact with the blank holder (30), the pressure detection module collects the real-time blank holder force value applied to the adjustment balance block and sends it to the intelligent decision module via the control module; The intelligent decision module generates a control instruction based on the acquired real-time blank holding force value and sends the control instruction to the control module; The control module drives the press and the lifting device according to the control instruction to adjust the blank holding force applied to the blank holding ring (30).

6. The control method according to claim 5, characterized in that: Before the step of the intelligent decision module generating a control instruction based on the acquired real-time blank holder force value and sending the control instruction to the control module, the method further includes: A corresponding standard pressure value is set for each balancing block component (40), and the standard pressure value is uploaded to the intelligent decision module.

7. The control method according to claim 6, characterized in that: The step of the intelligent decision module generating a control instruction based on the acquired real-time blank holder force value and sending the control instruction to the control module includes: Comparing the real-time blank holding force value or / and the sum thereof collected by the pressure detection module in each of the balancing block components (40) with the corresponding set value, and determining whether the blank holding force needs to be adjusted based on the comparison result; When it is determined that the blank holder force needs to be adjusted, an adjustment rule is formulated according to the comparison result, and the adjustment rule is sent to the control module.

8. The control method according to claim 7, characterized in that: The step of comparing the real-time blank holder force value or / and the sum thereof collected by the pressure detection module in each of the balancing block components (40) with the corresponding set value, and determining whether the blank holder force needs to be adjusted based on the comparison result comprises: Calculating whether the difference between the sum of the real-time blank holder force values collected by each of the pressure detection modules and a preset total pressure value is greater than a first preset value, and if so, determining that the overall blank holder force needs to be adjusted; or / and, Calculate whether the difference between the real-time blank holding force value collected by each pressure detection module and the corresponding standard pressure value is greater than a second preset value. If it is greater than the second preset value, determine that the local blank holding force needs to be adjusted.

9. The control method according to claim 8, characterized in that: When it is determined that the blank holder force needs to be adjusted, the step of formulating an adjustment rule according to the comparison result and sending the adjustment rule to the control module includes: When the difference between the sum of the real-time blank holding force values and the preset total pressure value is greater than the first preset value, formulating an adjustment rule for adjusting the overall blank holding force acting on the blank holding ring (30) by the press according to the difference; or / and, When the difference between the real-time blank holding force value collected by one or part of the pressure sensors and the corresponding standard pressure value is greater than the second preset value, an adjustment rule is formulated based on the difference to adjust the local blank holding force acting on the blank holding ring (30) by adjusting the height of the adjustment balance block in the balance block assembly (40) belonging to the pressure detection module.

10. The control method according to claim 9, characterized in that: The control module also includes an alarm device, The control method further includes: When the difference between the sum of the real-time blank holding force values and the preset total pressure value is greater than the preset value, or / When the difference between the real-time blank holding force value collected by one or part of the pressure sensors and the corresponding standard pressure value is greater than a preset value, The intelligent decision-making module sends an alarm instruction to the control module to control the alarm device to sound an alarm.

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