A stamping die and stamping method for a cylindrical head

Abstract

The present invention belongs to the technical field of sheet metal drawing forming in the metallurgical industry, and discloses a stamping die for a cylindrical head and a stamping forming method; the stamping die for the cylindrical head includes: an upper female die, a punch, a blank holder, a blank holder insert, and an insert support seat; the upper female die and the punch are arranged in cooperation; the blank holder is provided with a socket hole, and the blank holder is sleeved on the punch through the socket hole; the plurality of blank holder inserts are arranged at intervals, the plurality of blank holder inserts are arranged circumferentially along the socket hole of the blank holder, and the plurality of blank holder inserts are respectively fixed on the wall of the socket hole of the blank holder through the insert support seat; wherein, the insert support seat can move axially along the socket hole to adjust the fixed position. The stamping die for the cylindrical head and the stamping forming method provided by the present invention can overcome defects such as bulging, cracking, and local thinning easily occurring in the stamping forming of the cylindrical head.

Description

Technical Field

[0001] The present invention relates to the technical field of sheet metal drawing forming in the metallurgical industry, and particularly relates to a stamping die for a cylindrical head and a stamping forming method. Background Art

[0002] During the stamping process, due to large differences in the same plate of the material or local processing defects of the blank holder of the stamping die, it is easy to cause uneven metal flow during stamping, resulting in bulging defects in the circular head; in addition, fluctuations in the mechanical properties of the stamping raw materials will also cause stamping defects. For example, when the material strength is higher than the typical value, with the stamping process parameters unchanged, the insufficient metal deformation will be caused due to more metal flowing into the die cavity, resulting in a smaller flange edge or no flange edge in the drawing process, and subsequent shaping and trimming cannot be carried out; when the material strength is lower than the typical value, with the stamping parameters unchanged, due to the smaller drawing forming force, larger blank holding force, and less metal inflow, local excessive thinning or stamping cracking of the part will occur. Summary of the Invention

[0003] The present invention provides a stamping die for a cylindrical head and a stamping forming method, which solve the technical problems that the stamping forming of the cylindrical head in the prior art is prone to defects such as bulging, cracking, and local thinning.

[0004] To solve the above technical problems, the present invention provides a stamping die for a cylindrical head, including: an upper female die, a punch, a blank holder, blank holder inserts, and an insert support seat;

[0005] The upper female die and the punch are arranged in cooperation;

[0006] A socket hole is formed in the blank holder, and the blank holder is sleeved on the punch through the socket hole;

[0007] The blank holder inserts are multiple and arranged at intervals, the multiple blank holder inserts are arranged circumferentially along the socket hole of the blank holder, and the multiple blank holder inserts are respectively fixed on the wall of the socket hole of the blank holder through the insert support seat;

[0008] Wherein, the insert support seat can move axially along the socket hole to adjust and fix the position.

[0009] Further, a round chamfer is provided on the edge of the blank holder insert.

[0010] Further, the radius of the round chamfer is greater than or equal to 1 mm.

[0011] Further, the socket hole is a round hole, and the multiple blank holder inserts are arranged at equal intervals circumferentially along the round hole.

[0012] Further, the number of the blank holder inserts is 12 with the same size.

[0013] Furthermore, the blank-holder insert is a quasi-isosceles trapezoid block, and the two bottom sides of the quasi-isosceles trapezoid block are arc-shaped.

[0014] A stamping forming method for a cylindrical head, which performs stamping operations in combination with the stamping forming die for the cylindrical head; includes:

[0015] Establish a stamping simulation model for the cylindrical head, and obtain the relationship between the hardness of the material for stamping the cylindrical head and the blank-holder force;

[0016] Obtain the actual material hardness of the to-be-stamped sheet, and determine the actual blank-holder force for the stamping operation based on the relationship between the material hardness and the blank-holder force;

[0017] Obtain the thickness distribution state of the to-be-stamped sheet, and adjust the actual arrangement height of the plurality of blank-holder inserts based on the thickness distribution state;

[0018] Perform stamping operations based on the actual blank-holder force and the actual arrangement height.

[0019] Furthermore, the obtaining of the actual material hardness of the to-be-stamped sheet includes:

[0020] Respectively detect the hardness values corresponding to the multiple regions separated by the plurality of blank-holder inserts to obtain a plurality of measured hardness values;

[0021] Obtain the average hardness value of the plurality of measured hardness values as the actual material hardness.

[0022] Furthermore, based on the corresponding relationship between the material hardness and the material strength, and then determining the actual blank-holder force for the stamping operation according to the relationship between the strength and the blank-holder force includes:

[0023] Obtain the deviation ratio of the average hardness value relative to the marked hardness value of the to-be-stamped sheet;

[0024] Based on the corresponding relationship between the material hardness and the material strength, and then determining the actual blank-holder force for the stamping operation according to the relationship between the strength and the blank-holder force, obtain the initial blank-holder force corresponding to the marked hardness value of the to-be-stamped sheet;

[0025] Adjust the initial blank-holder force based on the deviation ratio to obtain the actual blank-holder force.

[0026] Furthermore, the obtaining of the thickness distribution state of the to-be-stamped sheet includes:

[0027] Respectively detect the thickness values corresponding to the multiple regions separated by the plurality of blank-holder inserts to obtain a plurality of measured thickness values;

[0028] Respectively obtain the deviation amounts of the plurality of measured thickness values relative to the marked thickness value of the to-be-stamped sheet;

[0029] Adjust the fixed height of the flattening inserts corresponding to the multiple regions respectively based on the deviation amount.

[0030] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0031] The cylindrical head stamping die and stamping method provided in the embodiments of the present application can measure the hardness and thickness of the stamping area of the stamping blank by arranging the blank holding inserts at intervals along the blank holder, so as to obtain the thickness and hardness conditions of the stamping area of the stamping blank. Combining the relationship between hardness and blank holding force determined by the simulation model, determine the matching setting of the fixed height difference of the blank holding inserts for the stamping area, meet the consistency of stamping distance and pace, and ensure stamping quality; it is also possible to obtain the accurate hardness condition of the stamping blank based on the actual hardness distribution, so as to improve the matching of the blank holding force, get closer to the reasonable blank holding force, and improve the stamping quality; realize the consistency and efficiency of the stamping material flow of the stamping blank through the coordinated cooperation of the blank holding force and the fixed height of the blank holding inserts, so as to avoid defects such as local bulging, cracking or local thinning. Description of the Drawings

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 Structural schematic diagram of the cylindrical head stamping die provided in the embodiments of the present invention;

[0034] Figure 2 For Figure 1 Arrangement schematic diagram of the blank holding inserts of the cylindrical head stamping die in

[0035] Figure 3 For Figure 1 Cross-sectional view of the cylindrical head stamping die in

[0036] Figure 4 Flowchart of the cylindrical head stamping method provided in the embodiments of the present invention. Detailed Embodiments

[0037] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0038] It should be noted that all the directional indications in the embodiments of the present application are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If this specific posture changes, the directional indications will also change accordingly.

[0039] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0040] The present application will be described below in conjunction with the accompanying drawings and with reference to specific embodiments.

[0041] By providing a cylindrical head stamping die and a stamping method in the embodiments of the present application, the technical problem that the cylindrical head stamping in the prior art is prone to defects such as bulging, cracking, and local thinning is solved.

[0042] To better understand the above technical solutions, the above technical solutions will be described in detail below in conjunction with the drawings of the specification and specific implementation manners. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solutions of the present application, rather than limitations on the technical solutions of the present application. Without conflict, the technical features in the embodiments of the present application and the embodiments can be combined with each other.

[0043] See Figure 1 、 Figure 2 and Figure 3 , the embodiments of the present application provide a cylindrical head stamping die. Through the arrangement of the blank holder inserts and in combination with the measurement of the hardness and thickness of the stamping blank in the area of the blank holder inserts, a collaborative stamping operation is realized, promoting the consistency of the metal inflow amount during the stamping process, reducing defects such as local bulging, cracking, and thinning, and ensuring the stamping quality of the cylindrical head.

[0044] Specific implementation schemes of the cylindrical head stamping die and stamping method to be described separately below.

[0045] The cylindrical head stamping die involved in the embodiment of the present application includes: an upper female die 1, a male die 2, and a blank holder 3. The upper female die 1 and the male die 2 are arranged in cooperation, and the blank holder 3 is sleeved on the male die 2 to perform the blank holding operation.

[0046] For the convenience of the blank holding operation, a socket hole is usually opened on the blank holder 3, and the blank holder 3 is sleeved on the male die 2 through the socket hole.

[0047] In order to adapt to the situation of uneven thickness of the blank to be stamped, a plurality of blank holding inserts 4 arranged at circumferential intervals can be provided at the socket hole of the blank holder 3. That is to say, the plurality of blank holding inserts 4 are arranged along the inner side of the socket, enclosing a circle, and the gap between two adjacent blank holding inserts 4 is controlled at a low level; generally, two adjacent blank holding inserts 4 can be made to abut against each other, but they can move up and down flexibly to a certain extent to facilitate adjusting the fixed height.

[0048] In order to ensure the attitude stability, convenient adjustment operation and fixed stability of the blank holding insert 4, a fixed insert support seat 7 can be additionally provided; the blank holding insert 4 is fixed on the insert support seat 7, and then the insert support seat 7 is adjustably fixed on the blank holder 3 through an adjusting fastener 5. A fastening bolt can be selected to achieve adjustable fixation, with convenient operation and high fixing reliability.

[0049] Similarly, the blank holding insert 4 can also be fixed on the insert support seat 7 through a detachable fastener 6, which is convenient for replacing accessories. Of course, the blank holding insert 4 can also be directly welded on the insert support seat 7, or the two are directly formed together, and the overall operation can be carried out during replacement and maintenance.

[0050] By adjusting the fixed height of the blank holding insert 4 to match the state of uneven thickness in the stamping area of the blank to be stamped, when stamping, the extrusion directly acting on the blank to be stamped is basically consistent, so that the metal flow-in amount is consistent, ensuring the forming uniformity and avoiding defects such as local bulging, cracking or excessive thinning.

[0051] In order to meet the convenience and reliability of the assembly of the plurality of blank holding inserts 4 arranged at circumferential intervals along the socket hole of the blank holder, a mating slot hole or other structures can be opened on the socket hole wall of the blank holder 3 to accommodate the insert support seat 7, and it can be fixedly pressed through an adjusting fastener.

[0052] Of course, slots can also be directly opened on the blank-holding side of the blank-holder 3 to accommodate and support the insert support base 7, thereby ensuring the stability of the support force during stamping. Of course, specific selection can be made flexibly according to the intensity of the stamping operation and the requirements of the workpiece forming process.

[0053] It should be noted that the adjustment direction of the insert support base 7 is along the axial direction of the socket hole. That is to say, by adjusting the fixed position of the insert support base 7 along the axial direction of the socket hole, the distance between the stamping surface of the blank-holder insert 4 and the to-be-stamped sheet is adjusted to meet the actual state of different thicknesses of the to-be-stamped sheet and ensure the consistency of the stamping inflow.

[0054] Considering the situation that the blank-holder insert 4 has height fluctuations, in order to prevent the edge of the blank-holder insert 4 from cutting the sheet during stamping, a round chamfer is provided on the edge of the blank-holder insert 4 to avoid mechanical cutting. Generally, the round chamfer is mainly provided at the adjacent edges of two adjacent blank-holder inserts 4; of course, it does not exclude the case where the inner edge of the blank-holder insert 4, that is, the side close to the stamping workpiece, also has a round chamfer.

[0055] Generally, the size of the round chamfer can be determined according to the size and bending amplitude of the sheet. Generally, the radius of the round chamfer can be controlled to be greater than or equal to 1 mm.

[0056] During normal stamping operations, the socket hole is set as a round hole, and the multiple blank-holder inserts 4 are arranged at equal intervals along the circumference of the round hole, enclosing a closed circle.

[0057] To balance the adjustment complexity, structural complexity, and the necessity of a too-small actual area, the blank-holder inserts 4 can be set to 12 pieces of the same size, each covering a 30-degree sector area.

[0058] Of course, more or fewer numbers are not excluded, mainly considering the size of the stamping part, the hardness and thickness of the sheet. Generally, if the sheet curvature and plate difference are too large, the thickness non-uniformity is too large, and the size is too large, the number of the blank-holder inserts accordingly can be set relatively more.

[0059] Generally, in order to reduce the influence of the shape and combined connection state of the blank-holder insert 4 on the metal flow and forming quality during stamping, the blank-holder insert 4 can be set as a quasi-isosceles trapezoidal block, and the two bottom edges of the quasi-isosceles trapezoidal block are arc-shaped, so as to be able to cover the complete stamping area and avoid forming too-small sharp corners, resulting in mechanical cracking and bulging.

[0060] Through the above die design, the stamping operation can be optimized to a certain extent to ensure the stamping forming quality. The stamping forming method combining the above die will be described below.

[0061] See Figure 4, a stamping forming method for a cylindrical head specifically includes:

[0062] Establish a stamping simulation model of the cylindrical head to obtain the relationship between the hardness of the material for stamping the cylindrical head and the blank holding force;

[0063] Obtain the actual material hardness of the blank to be stamped, and based on the corresponding relationship between the material hardness and the material strength, then determine the actual blank holding force for the stamping operation according to the relationship between the strength and the blank holding force;

[0064] Obtain the thickness distribution state of the blank to be stamped, and adjust the actual arrangement height of the multiple blank holding inserts based on the thickness distribution state;

[0065] Perform the stamping operation based on the actual blank holding force and the actual arrangement height.

[0066] Among them, the obtaining of the actual material hardness of the blank to be stamped includes:

[0067] Detect the hardness values corresponding to the multiple regions divided by the multiple blank holding inserts respectively to obtain a plurality of measured hardness values;

[0068] Obtain the average hardness value of the multiple measured hardness values as the actual material hardness.

[0069] Generally speaking, the hardness of the blank to be stamped is usually set with a marked hardness value, that is, as the material of the corresponding specification, its hardness is theoretically known, that is, the marked hardness value. However, during the product process, affected by the process and operation, there is usually a certain change relative to the marked hardness value, which is usually manifested as regional differences.

[0070] In this embodiment, through regionalized detection, the actual hardness of the current blank to be stamped can be accurately obtained, so as to accurately obtain the corresponding blank holding value and obtain good stamping quality. Generally speaking, there are not large differences in the stamping parts, so the regional average value has a certain representativeness, and a reasonable blank holding force can be obtained from the average value.

[0071] Considering that the stamping control method is the range control of parameter values, it is usually difficult to directly control to a certain specific value. Therefore, the determining of the actual blank holding force for the stamping operation based on the relationship between the material hardness and the blank holding force includes:

[0072] Obtain the deviation ratio of the average hardness value relative to the marked hardness value of the blank to be stamped;

[0073] Based on the relationship between the material hardness and the blank holding force, obtain the initial blank holding force corresponding to the marked hardness value of the blank to be stamped;

[0074] Adjust the initial blank holding force based on the deviation ratio to obtain the actual blank holding force.

[0075] That is, when setting stamping parameters, based on the deviation ratio, the left and right range control based on the marked value is implemented, so that when serial production is implemented, the threshold range can be correspondingly controlled based on the actual hardness.

[0076] When controlling the blank holder insert 4, the obtaining of the thickness distribution state of the to-be-stamped sheet includes:

[0077] Respectively detecting the thickness values corresponding to the multiple regions divided by the multiple blank holder inserts 4 to obtain multiple measured thickness values;

[0078] Respectively obtaining the deviation amounts of the multiple measured thickness values relative to the marked thickness value of the to-be-stamped sheet;

[0079] Based on the deviation amounts, respectively adjusting the fixed heights of the flattening inserts corresponding to the multiple regions.

[0080] The following will be described by a specific embodiment.

[0081] The present invention discloses a cylindrical head stamping die and its compensation method. It mainly includes the following steps:

[0082] Establishment and analysis of the simulation model. In this example, the material used is STC330R with a specification of 1.8 mm, the blank size diameter is 442 mm, the punch diameter is 350 mm, and the drawing height is 100 mm.

[0083] In order to more accurately obtain the blank holding force required during the stamping forming of the head, it is necessary to model and simulate the head. Through the mechanical tensile test, three-dimensional mechanical property data is obtained. The mechanical property data of the typical (stable production performance) of the material is input into the Autoform material card. After calculation, the reasonable blank holding force value can be obtained, and based on this performance value as the benchmark, the reasonable blank holding force values within the range of plus or minus 10% are calculated.

[0084] Import this material mechanical property data into the simulation software AUTOFORM, and through finite element simulation for debugging, the analysis result shows that the blank holding force when the forming is good is F medium 73T. In addition, the actual sheet is sent to the hydraulic press for comparison with the simulation analysis result, and it is obtained that the result is consistent with the analysis result, and the blank holding force at this time is F actual 74.5T, and the error is less than 3%;

[0085] Detection of sheet thickness and hardness. The sheet is conveyed from the blank frame to the designated position of the die through the conveying device. A thickness and hardness detection device is installed on the conveying device. The device is distributed in a ring shape, with a total of 12 detection points, which respectively correspond to the edge regions of the 12 equal parts of the sheet. Through this device, the hardness and thickness values of each detection point can be fed back to the control system.

[0086] In the stamping forming compensation method, the material strength and the surface hardness of the material are in a linear correspondence. The specific correspondence is shown in the corresponding table of hardness and strength in Appendix 1. The material strength is closely related to the forming force and the reasonable blank holding force during stamping (see the relationship below). Therefore, the invention can detect the degree of fluctuation of the material hardness to measure the degree of fluctuation of the material strength, and then the blank holding force can be reasonably controlled by the control system to obtain a good quality stamping part. The simulation analysis of step 1 shows that when the typical mechanical properties of the material are input, the reasonable blank holding force F of good stamping quality is calculated. Taking F as the benchmark, the relationship between material strength and blank holding force is calculated. At this time, the tensile strength σ b As a benchmark for material strength.

[0087] Relationship between material strength and blank holding force

[0088]

[0089] Hardness and strength correspondence table

[0090]

[0091]

[0092] Transmit the thickness and hardness test values to the control system for calculation and analysis:

[0093] Hardness value: The main control system sets the hardness values of 12 areas as HB1, HB2...HB 12 Take the average value to get HB AG The hardness value HB of typical mechanical properties materials is used as the hardness value benchmark. AG and HB 中 Compare and calculate based on the benchmark hardness value HB 中 The upper and lower offset HB%, according to the hardness value HB%, gives the offset F of the blank holder force F, and F 中 ±F is transmitted to the pressure hydraulic cylinder control system to achieve the pressure compensation effect; b. Thickness value: The control system transmits the thickness values d1, d2...d 12 , transmitted to the control systems of each edge-holder insert through the main control system, and the thickness compensation action is performed. That is, after the sheet thickness d is input, the main control system calculates the thickness deviation ±d at each position. i (greater than d is recorded as d i or +d i , which is less than d is recorded as -d i ), thickness deviation ±d i The main control system transmits the information to the edge-pressing insert control system and performs up and down offset actions to achieve thickness compensation effect.

[0094] The stamping forming compensation die for the cylindrical head mainly consists of a concave die, a blank holder, and a convex die. The blank holding part of the blank holder is composed of blank holding inserts. In order to better control the metal flow of the circular blank and for the convenience of machining and manufacturing the inserts, the annular blank holding area is divided into 12 equal parts, and the included angle between the two straight opposite sides of each blank holding insert is 30°. The straight parts between the two inserts are all rounded with a radius of 1 mm. This requirement is to avoid scratching the sheet metal at the edge of the insert during stamping after thickness compensation during the metal flow process.

[0095] Based on the above material mechanical properties, the reasonable blank holding force within the range of ±10% fluctuation of the material strength is calculated, and then the reasonable blank holding force values F corresponding to each strength of the material are obtained.

[0096] At this time, the surface hardness value HB of the reference material is measured to be 124.

[0097] The hardness values HB1, HB2... HB of the 12 regions 12 Take the average value to obtain HB AG Which is 128.

[0098] The thickness values d1, d2... d of the 12 regions 12 Measured: 1.785 mm, 1.787 mm, 1.789 mm, 1.792 mm, 1.795 mm, 1.793 mm, 1.796 mm, 1.799 mm, 1.803 mm, 1.798 mm, 1.791 mm, 1.786 mm;

[0099] The hardness value HB AG Of 128 is transmitted to the total control system through the detection device, and the offset of the hardness HB% is calculated through comparison. According to the relationship between the material strength and hardness, the change amount σ of the material strength can be calculated based on the hardness value offset HB%. 中 Based on the blank holding force F obtained from the above simulation analysis results, the corresponding blank holding force F1 is obtained as 76T. b The main control system transmits F1: 76T to the blank holder hydraulic system and performs stamping at this pressure.

[0100] The main control system calculates and compares the thickness values of each region transmitted by the detection device with the previously input thickness target value of 1.8 mm, and sends the calculated deviation amount to the blank holding insert control system. At this time, the blank holding insert control system performs the thickness compensation action.

[0101] Finally, through the above blank holding force and thickness compensation for stamping forming, a product with good forming quality can be obtained.

[0102] Finally, through the above blank holding force and thickness compensation for stamping forming, a product with good forming quality can be obtained.

[0103] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0104] The cylindrical head stamping die and stamping method provided in the embodiments of the present application can measure the hardness and thickness of each blank holder insert area along the blank holder, so as to obtain the thickness and hardness of the stamping area of the stamping blank. Combining the hardness and blank holding force relationship determined by the simulation model, the matching setting of the fixed height difference of the blank holder inserts for the stamping area is determined to meet the consistency of the stamping distance and pace and ensure the stamping quality. It is also possible to obtain the accurate hardness of the stamping blank based on the actual hardness distribution, so as to improve the matching of the blank holding force, make it closer to the reasonable blank holding force, and improve the stamping quality. The consistency and efficiency of the stamping material flow of the stamping blank are realized through the coordinated cooperation of the blank holding force and the fixed height of the blank holder inserts, thus avoiding defects such as local bulging, cracking or local thinning.

[0105] In the present application, unless otherwise clearly defined and limited, terms such as "connection" and "fixation" shall be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0106] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0107] In addition, in the present application, descriptions such as "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions conflicts with each other or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0108] In the description of the present invention, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the contact between the first and second features not being direct but through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely means that the horizontal height of the first feature is less than that of the second feature.

[0109] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0110] Although the preferred embodiments of the present application have been described, those of ordinary skill in the art can make additional changes and modifications once they learn the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present application.

[0111] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these changes and modifications.

Claims

1. A stamping forming method for a cylindrical head, which performs stamping operations in combination with a stamping forming die for the cylindrical head; characterized in that, The stamping and forming die for the cylindrical head includes: an upper female die, a punch, a blank holder, blank holder inserts, and an insert support seat; The upper female die and the punch are arranged in cooperation; A socket hole is formed in the blank holder, and the blank holder is sleeved on the punch through the socket hole; The blank holder inserts are multiple and arranged at intervals. The multiple blank holder inserts are arranged circumferentially along the socket hole of the blank holder, and the multiple blank holder inserts are respectively fixed on the wall of the socket hole of the blank holder through the insert support seat; Wherein, the insert support seat can move axially along the socket hole to adjust the fixed position; The stamping operation includes: Establish a stamping simulation model of the cylindrical head, and obtain the relationship between the hardness of the material for stamping the cylindrical head and the blank holding force; Obtain the actual material hardness of the to-be-stamped sheet, and determine the actual blank holding force of the stamping operation based on the relationship between the material hardness and the blank holding force; Obtain the thickness distribution state of the to-be-stamped sheet, and adjust the actual arrangement height of the multiple blank holder inserts based on the thickness distribution state; Perform the stamping operation based on the actual blank holding force and the actual arrangement height; Wherein, the obtaining of the actual material hardness of the to-be-stamped sheet includes: Respectively detect the hardness values corresponding to the multiple regions separated by the multiple blank holder inserts to obtain multiple measured hardness values; Obtain the average hardness value of the multiple measured hardness values as the actual material hardness; The determining of the actual blank holding force of the stamping operation based on the relationship between the material hardness and the blank holding force includes: Obtain the deviation ratio of the average hardness value relative to the marked hardness value of the to-be-stamped sheet; Obtain the initial blank holding force corresponding to the marked hardness value of the to-be-stamped sheet based on the relationship between the material hardness and the blank holding force; Adjust the initial blank holding force based on the deviation ratio to obtain the actual blank holding force.

2. The method for stamping and forming a cylindrical head according to claim 1, wherein, The obtaining of the thickness distribution state of the to-be-stamped sheet includes: Respectively detect the thickness values corresponding to the multiple regions separated by the multiple blank holder inserts to obtain multiple measured thickness values; Respectively obtain the deviation amounts of the multiple measured thickness values relative to the marked thickness value of the to-be-stamped sheet; Based on the deviation amounts, respectively adjust the fixed heights of the blank holder inserts corresponding to the multiple regions.

3. The stamping forming method of the cylindrical head according to claim 1, characterized in that, A circular chamfer is provided on the edge of the blank holder insert.

4. The stamping forming method of the cylindrical head according to claim 3, characterized in that, The radius of the circular chamfer is greater than or equal to 1 mm.

5. The stamping forming method of the cylindrical head according to claim 1, characterized in that, The socket hole is a circular hole, and the multiple blank holder inserts are arranged at equal intervals circumferentially along the circular hole.

6. The stamping forming method of the cylindrical head according to claim 5, wherein, There are 12 blank holder inserts of the same size.

7. The stamping forming method of the cylindrical head according to claim 5, characterized in that, The blank holder insert is a quasi-isosceles trapezoidal block, and the two bottom sides of the quasi-isosceles trapezoidal block are arc-shaped.

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