Aluminum cap sheet stretching device, stretching method and application in two-piece can production

Abstract

The present invention relates to the technical field of can stretching manufacturing, and discloses an aluminum cap sheet stretching device, a stretching method, and an application in the production of two-piece cans. The device includes a stretching assembly, and the stretching assembly includes a frame, a stretching platform is arranged above the frame, a stamping die and a stretching die are arranged above the stretching platform, and a stamping assembly and a bottom forming assembly are respectively arranged at both ends of the frame, and a fixing assembly and an adjusting assembly are arranged on one side of the stamping die, and the adjusting assembly is arranged inside the fixing assembly. The present invention detects and determines whether the aluminum cap sheet between the pressure ring and the pressure plate is in the center position through the cooperation of the fixing assembly and the adjusting assembly, and at the same time, by adjusting the position of the pressure plate, the tensile stress on the aluminum cap sheet during the stamping and stretching of the cup body is changed, so as to ensure the concentricity of the aluminum cap sheet and the die and the straightness of the product forming.

Description

Technical Field

[0001] The invention belongs to the technical field of can stretching manufacturing, and specifically relates to an aluminum cap sheet stretching device, a stretching method and an application in the production of two-piece cans. Background Art

[0002] Two-piece cans, abbreviated as two-piece cans, refer to metal containers consisting of a can cover (top) and an integral seamless can body with a bottom. Two-piece cans have the characteristics of light weight, thin wall, high mechanical strength, and good sealing. The can body of this type of metal container is processed by an integrated stamping and stretching process on an aluminum cap sheet. Based on the principle of metal plastic deformation, during the stretching process, the aluminum material is subjected to plastic deformation due to the action of external force. Specifically, the aluminum cap sheet is firstly stamped and stretched into a cup body, and then the cup body is gradually thinned and formed into a can body through multiple stretching dies. Finally, the bottom of the can body is stamped and formed. The aluminum cap sheet stretching device is widely used in the production of two-piece cans. It can not only improve production efficiency and ensure product quality, but also reduce production costs.

[0003] For example, a Chinese patent with application number 202322845369X discloses a stretching machine with a guiding function, including a stretching bottom plate, a fixed plate is fixedly installed on the left end of the upper end of the stretching bottom plate, an electric push rod is fixedly installed on the right end of the fixed plate, a stretching push rod is fixedly installed on the right end of the electric push rod, a bottom mold groove of a can is fixedly provided on the right end of the stretching push rod, a slide groove is fixedly provided on the upper end of the stretching bottom plate, a limiting groove is fixedly provided in the middle of the slide groove, and a guide ring is movably installed on the upper end of the slide groove. The stretching machine is installed with multiple stretching frames and stretching mold rings, and the multiple stretching mold rings gradually shrink from left to right, so that the can can be gradually elongated when pushed to the right, thereby improving the stability during stretching. However, the above scheme cannot adjust the clamping force in real time according to the thickness of the aluminum cap sheet.

[0004] If the aluminum cap sheet is offset from the mold position, the product quality will be reduced and the production efficiency will be affected. Since the specifications of the cans required for production are different, the thickness of the aluminum cap sheet required is also different, and the existing method cannot adjust the clamping force in real time according to the thickness of the aluminum cap sheet. When the aluminum cap sheet is initially stamped and stretched into a cup body under the action of the stamping die and the stamping head, the degree of stretching at different positions of the aluminum cap sheet is different due to the uneven material distribution or temperature of the aluminum cap sheet itself, which affects the uniformity of product stretching. Summary of the invention

[0005] In view of the above problems, the present invention provides an aluminum cap sheet stretching device, a stretching method and application in the production of two-piece cans to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: an aluminum cap sheet stretching device, comprising a stretching assembly, the stretching assembly comprising a frame, a stretching platform is arranged above the frame, a stamping die and a stretching die are arranged above the stretching platform, a stamping assembly and a bottom forming assembly are respectively arranged at both ends of the frame, a fixing assembly and an adjusting assembly are arranged on one side of the stamping die, and the adjusting assembly is arranged inside the fixing assembly;

[0007] The fixing assembly comprises a positioning plate, the positioning plate is arranged on one side of the stamping die, a compression spring is arranged on the surface of the positioning plate, and a compression ring is arranged at one end of the compression spring away from the positioning plate;

[0008] The adjustment assembly comprises a mounting frame, a mounting seat is arranged on one side of the mounting frame, a movable groove is opened on the surface of the mounting seat, and an adjustment spring is arranged inside the movable groove, a movable rod is arranged at one end of the adjustment spring away from the movable groove, a pressure plate is arranged on one side of the movable rod away from the mounting seat, and a pressure sensor is arranged inside the pressure plate;

[0009] An electromagnet is arranged inside the mounting seat, an armature block is arranged inside the movable rod, and the armature block is arranged at one end of the movable rod close to the adjusting spring.

[0010] Preferably, the stamping die is arranged at one end of the stretching table close to the stamping assembly, and the stretching die is arranged at a side of the stamping die away from the stamping assembly;

[0011] There are multiple stretching dies, and the multiple stretching dies are arranged on the stretching table at equal intervals, and the stretching diameter of the stretching die close to the stamping die is larger than the stretching diameter of the stretching die far from the stamping die.

[0012] Preferably, a heating sleeve is provided on the outer surface of the stretching die, a positioning frame is provided below the stamping die, the positioning frame is provided on the surface of the stretching table, clamping plates are provided on both sides of the stretching die, and a clamping groove is provided at the position where the clamping plate is connected to the stretching table.

[0013] Preferably, cylinders are arranged at the four corners of the surface of the positioning plate, a fixing frame is arranged at one end of the cylinder away from the positioning plate, and the fixing frame is arranged at one side of the stamping die;

[0014] Connecting plates are arranged on both sides of the pressure ring, a guide column is arranged at one end of the connecting plate close to the positioning plate, and a guide hole is provided at the position where the positioning plate is connected to the guide column.

[0015] Preferably, there are multiple mounting seats, which are arranged in a ring shape on the surface of the mounting frame. A sliding groove is provided at the position where the mounting frame is connected to the pressure plate, and the movable rod is adapted to the movable groove.

[0016] Preferably, the punching assembly comprises a fixed seat, the fixed seat is arranged at one end of the frame, a hydraulic rod is arranged at the center of the surface of the fixed seat, a punching head is arranged at one end of the output shaft of the hydraulic rod, and a plurality of support seats are arranged at equal intervals below the hydraulic rod;

[0017] One end of the support base away from the hydraulic rod is connected to the frame, and an arc-shaped groove is formed at the end of the support base away from the frame, and a buffer pad is arranged inside the arc-shaped groove.

[0018] Preferably, the bottom forming assembly includes a buffer plate, which is arranged on a frame, a limiting column is arranged at the center position of the surface of the buffer plate, a limiting cylinder is arranged at one end of the limiting column away from the buffer plate, a buffer frame is arranged at one end of the limiting cylinder away from the limiting column, and a bottom mold is arranged inside the buffer frame.

[0019] Preferably, a return spring is provided on the outer surface of the limit column, one end of the return spring is fixedly connected to the buffer plate, the end of the return spring away from the buffer plate is fixedly connected to the limit cylinder, and a limit groove is provided at the position where the limit cylinder is connected to the limit column.

[0020] The present invention also provides a stretching method for an aluminum cap sheet, and the specific stretching method steps are as follows:

[0021] S1: First, the aluminum cap sheet to be processed is fixed by cooperating with the fixing component and the adjusting component, and the blank holding force is adjusted accordingly according to the different thicknesses of the aluminum cap sheet;

[0022] S2: Then, under the action of the stamping assembly, the aluminum cap sheet passes through the stamping die and multiple stretching dies in sequence, so that the aluminum cap sheet undergoes plastic deformation and finally forms the desired can body;

[0023] S3: Finally, under the joint action of the stamping component and the bottom forming component, the bottom of the can body is stamped, so that the bottom of the can body is concave in a round arch shape, so that it can withstand greater pressure.

[0024] The present invention also provides the use of the aluminum cap sheet stretching device as described above in the production of two-piece cans.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention detects and determines whether the aluminum cap sheet between the pressure ring and the pressure plate is in the center position by cooperating with the fixing component and the adjusting component, so as to avoid the aluminum cap sheet and the mold position being offset, which will lead to a decline in product quality and affect production efficiency. At the same time, the thickness of the aluminum cap sheet is detected by the deformation of the compression spring, and the pressure force of the pressure ring on the aluminum cap sheet is adjusted accordingly according to the thickness to avoid affecting the molding quality of the product.

[0027] 2. The present invention adjusts the position of the pressure plate by arranging an adjusting spring, a movable rod, a pressure plate, an electromagnet, an armature block and other structures to change the tensile stress on the aluminum cap sheet when the cup body is stamped and stretched, and effectively solves the problem of different stretching degrees at different positions of the aluminum cap sheet due to uneven material distribution or uneven temperature of the aluminum cap sheet itself, which affects the uniformity of product stretching. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the structure of the stretching assembly of the present invention;

[0030] Figure 3 It is a schematic diagram of the structure of the fixing assembly of the present invention;

[0031] Figure 4 This is a schematic diagram of the structure of the regulating component of the present invention;

[0032] Figure 5 It is a schematic diagram of the assembly structure of the frame, the stamping assembly and the bottom forming assembly of the present invention;

[0033] Figure 6 It is a schematic cross-sectional view of the limiting cylinder structure of the present invention;

[0034] Figure 7 It is a schematic diagram of the assembly structure of the stretching component, the fixing component and the adjusting component of the present invention.

[0035] In the figure: 1. stretching assembly; 101. frame; 102. stretching table; 103. stamping die; 104. stretching die; 105. heating sleeve; 106. positioning frame; 107. clamping plate; 2. fixing assembly; 201. fixing frame; 202. cylinder; 203. positioning plate; 204. compression spring; 205. pressure ring; 206. connecting plate; 207. guide column; 3. adjustment assembly; 301. mounting frame; 302. mounting seat; 303. adjustment spring; 304. movable rod; 305. pressure plate; 4. stamping assembly; 401. fixing seat; 402. hydraulic rod; 403. stamping head; 404. supporting seat; 5. bottom forming assembly; 501. buffer plate; 502. limiting column; 503. limiting cylinder; 504. buffer frame; 505. bottom mold; 506. reset spring. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] like Figures 1 to 7 As shown, an aluminum cap sheet stretching device of the present invention includes a stretching component 1, the stretching component 1 includes a frame 101, a stretching platform 102 is arranged above the frame 101, a stamping die 103 and a stretching die 104 are arranged above the stretching platform 102, a stamping component 4 and a bottom forming component 5 are respectively arranged at both ends of the frame 101, a fixing component 2 and an adjusting component 3 are arranged on one side of the stamping die 103, and the adjusting component 3 is arranged inside the fixing component 2.

[0038] The stamping die 103 is disposed at one end of the stretching platform 102 close to the stamping component 4 , and the stretching die 104 is disposed at a side of the stamping die 103 away from the stamping component 4 .

[0039] like Figure 1 , Figure 2 As shown, there are multiple stretching dies 104 , and the multiple stretching dies 104 are arranged on the stretching platform 102 at equal intervals, and the stretching diameter of the stretching die 104 close to the stamping die 103 is larger than the stretching diameter of the stretching die 104 away from the stamping die 103 .

[0040] When in use, by setting a plurality of stretching dies 104 with different stretching diameters, a thinning forming effect can be achieved. Such gradual stretching can ensure the uniformity of the material during the deformation process, reduce the risk of fracture due to local stress concentration, and improve the surface quality of the product. In addition, the wall thickness and diameter of the product can be controlled more accurately, thereby improving the utilization rate of the material and the consistency of the product.

[0041] like Figure 2 As shown, a heating sleeve 105 is provided on the outer surface of the stretching die 104. The stretching die 104 is heated by providing the heating sleeve 105 to improve the plasticity of the can material and make it easier to be stretched and deformed in the stretching die 104. A positioning frame 106 is provided below the stamping die 103. The positioning frame 106 is provided on the surface of the stretching platform 102. Card plates 107 are provided on both sides of the stretching die 104. A card slot is provided at the position where the card plate 107 is connected to the stretching platform 102. The stretching die 104 is fixed on the stretching platform 102 by the cooperation of the card plate 107 and the card slot.

[0042] like Figure 3As shown, the fixing assembly 2 includes a positioning plate 203 , which is disposed on one side of the stamping die 103 , a compression spring 204 is disposed on the surface of the positioning plate 203 , and a pressure ring 205 is disposed at one end of the compression spring 204 away from the positioning plate 203 .

[0043] Cylinders 202 are provided at the four corners of the surface of the positioning plate 203, a fixing frame 201 is provided at one end of the cylinder 202 away from the positioning plate 203, the fixing frame 201 is provided on one side of the stamping die 103, connecting plates 206 are provided on both sides of the pressure ring 205, a guide column 207 is provided at one end of the connecting plate 206 close to the positioning plate 203, and a guide hole is opened at the position where the positioning plate 203 and the guide column 207 are connected.

[0044] When in use, the controller controls the cylinder 202 to contract, and the cylinder 202 drives the positioning plate 203, the compression spring 204 and the pressure ring 205 to move in the direction close to the stamping die 103, so that the pressure ring 205 clamps and fixes the aluminum cap sheet. During this process, the pressure ring 205 is squeezed by the aluminum cap sheet and drives the connecting plate 206 and the guide column 207 to move in the direction close to the positioning plate 203, and the guide column 207 moves in the guide hole. At this time, the compression spring 204 is compressed and deformed. By detecting the deformation of the compression spring 204, the thickness of the aluminum cap sheet can be obtained.

[0045] like Figure 4 As shown, the adjustment component 3 includes a mounting frame 301, a mounting seat 302 is arranged on one side of the mounting frame 301, a movable groove is opened on the surface of the mounting seat 302, and an adjustment spring 303 is arranged inside the movable groove, a movable rod 304 is arranged at the end of the adjustment spring 303 away from the movable groove, a pressure plate 305 is arranged on the side of the movable rod 304 away from the mounting seat 302, a pressure sensor is arranged inside the pressure plate 305, and the pressure on the pressure plate 305 is detected by the pressure sensor, an electromagnet is arranged inside the mounting seat 302, an armature block is arranged inside the movable rod 304, and the armature block is arranged at one end of the movable rod 304 close to the adjustment spring 303.

[0046] There are multiple mounting seats 302 , which are arranged in a ring shape on the surface of the mounting frame 301 . A sliding groove is provided at the position where the mounting frame 301 is connected to the pressure plate 305 , and the movable rod 304 is adapted to the movable groove.

[0047] When in use, the controller controls the electromagnet to start and pass a forward current, so that a magnetic attraction force is generated between the electromagnet and the armature block. When the magnetic attraction force is greater than the elastic force of the adjusting spring 303, the armature block moves toward the direction close to the electromagnet, and the adjusting spring 303 is compressed. During this process, the pressure plate 305 drives the movable rod 304 to move toward the direction close to the mounting seat 302, thereby changing the position of the pressure plate 305.

[0048] like Figure 1 , Figure 5 As shown, the stamping assembly 4 includes a fixed seat 401, which is arranged at one end of the frame 101, a hydraulic rod 402 is arranged at the center position of the surface of the fixed seat 401, a punching head 403 is arranged at one end of the output shaft of the hydraulic rod 402, and a plurality of support seats 404 are arranged at equal intervals below the hydraulic rod 402, and the end of the support seat 404 away from the hydraulic rod 402 is connected to the frame 101, and an arc-shaped groove is formed at the end of the support seat 404 away from the frame 101, and a buffer pad is arranged inside the arc-shaped groove. The support seat 404 and the buffer pad cooperate with each other to increase the support strength of the hydraulic rod 402 when it is extended, thereby ensuring that the punching head 403 moves stably during stamping.

[0049] like Figure 5 , Figure 6 As shown, the bottom forming assembly 5 includes a buffer plate 501, which is arranged on the frame 101. A limiting column 502 is arranged at the center position of the surface of the buffer plate 501. A limiting cylinder 503 is arranged at one end of the limiting column 502 away from the buffer plate 501. A buffer frame 504 is arranged at one end of the limiting cylinder 503 away from the limiting column 502. A bottom mold 505 is arranged inside the buffer frame 504.

[0050] A return spring 506 is provided on the outer surface of the limiting column 502, one end of the return spring 506 is fixedly connected to the buffer plate 501, and the end of the return spring 506 away from the buffer plate 501 is fixedly connected to the limiting cylinder 503, and a limiting groove is provided at the position where the limiting cylinder 503 is connected to the limiting column 502.

[0051] When in use, under the action of the punch head 403, the punch head 403 pushes the stretched can body to move towards the direction close to the bottom mold 505, and the bottom of the can body is stamped and formed by setting the bottom mold 505, so that the bottom of the can body is a circular arched depression. In this process, the purpose of buffering is achieved through the cooperation of structures such as the buffer frame 504, the limit cylinder 503, the limit column 502 and the return spring 506.

[0052] The inventors found that if the aluminum cap sheet is offset from the mold position, the product quality will be reduced and the production efficiency will be affected; since the specifications of the cans required for production are different, the thickness of the aluminum cap sheet required is also different, and the existing method cannot adjust the clamping force in real time according to the thickness of the aluminum cap sheet; when the aluminum cap sheet is initially stamped and stretched into a cup body under the action of the stamping die 103 and the stamping head 403, the degree of stretching at different positions of the aluminum cap sheet is different due to the uneven material distribution or uneven temperature of the aluminum cap sheet itself, which affects the uniformity of product stretching.

[0053] When in use, in the initial state, the controller controls multiple electromagnets to start simultaneously and pass forward current, so that a magnetic attraction force is generated between the electromagnet inside the mounting seat 302 and the armature block inside the movable rod 304. At this time, under the joint action of the magnetic attraction force and the adjustment spring 303, the pressure plate 305 is in the initial position, and the movable rod 304 does not move in the movable groove.

[0054] First, the aluminum cap piece is sucked by the robot and placed between the pressure plate 305 and the pressure ring 205. The controller controls the cylinder 202 to contract. The cylinder 202 drives the positioning plate 203, the compression spring 204 and the pressure ring 205 to move in the direction close to the stamping die 103, that is, the positioning plate 203 moves to the preset position, so that the pressure ring 205 clamps and fixes the aluminum cap piece. In this process, the pressure ring 205 is squeezed by the aluminum cap piece and drives the connecting plate 206 and the guide column 207 to move in the direction close to the positioning plate 203, and the guide column 207 moves in the guide hole. At this time, the compression spring 204 is compressed and deformed. The thickness of the aluminum cap piece can be obtained by detecting the deformation of the compression spring 204.

[0055] The aluminum cap piece is clamped and fixed by the pressure ring 205 and the pressure plate 305. At this time, the pressure value of the aluminum cap piece is detected by the pressure sensor in the pressure plate 305 at different positions. The detection result is used to determine whether the aluminum cap piece is in the center position. Specifically,

[0056] If the pressure values ​​detected by the pressure sensors in the pressure plate 305 at different positions are the same, it indicates that the aluminum cap piece is in the center position, that is, the aluminum cap piece is in the same concentricity with the stamping die 103 and the stretching die 104, and the position of the aluminum cap piece has not shifted, thereby ensuring product quality and product accuracy.

[0057] If the pressure values ​​detected by the pressure sensor in the pressure plate 305 at different positions are different, it means that the aluminum cap piece is not in the center position, that is, the aluminum cap piece is not in the same concentricity with the stamping die 103 and the stretching die 104, and the position of the aluminum cap piece is offset. This indicates that there is a quality problem with the aluminum cap piece. In order to improve production efficiency, the aluminum cap piece is removed by suction by a robot and then replaced with a new one.

[0058] It is worth mentioning that when the aluminum cap piece is not placed, when the positioning plate 203 is in the preset position, the end of the pressure ring 205 away from the compression spring 204 contacts the pressure plate 305, and the compression spring 204 is in the original length state. At this time, the pressure value of the pressure plate 305 detected by the pressure sensor is zero, and when the aluminum cap piece is placed, when the positioning plate 203 is in the preset position, the compression spring 204 is compressed and deformed. By detecting the deformation of the compression spring 204, the thickness of the aluminum cap piece can be obtained. At this time, the pressure on the pressure plate 305 detected by the pressure sensor can be used to obtain the pressure of the compression spring 204 on the aluminum cap piece at this time, and then the deformation of the compression spring 204 can be obtained by calculating the pressure of the compression spring 204, that is, the deformation of the compression spring 204 is the thickness of the aluminum cap piece.

[0059] When producing cans, the longer the cans are, the thicker the aluminum cap sheet is, and the smaller the required blanking force is. If the pressure of the pressing ring 205 on the aluminum cap sheet is too small, the flow resistance of the aluminum cap sheet during the stretching process is unevenly distributed, resulting in wrinkles at the edge. If the pressure of the pressing ring 205 on the aluminum cap sheet is too large, the material wall at this position becomes thinner or even cracked, affecting the surface quality of the product. In order to solve this problem, the blanking force on the aluminum cap sheet is adjusted by the fixing component 2 according to the thickness of the aluminum cap sheet, specifically: The controller controls the cylinder 202 to contract, and the cylinder 202 drives the positioning plate 203, the compression spring 204 and the pressure ring 205 to move toward the direction close to the stamping die 103. During this process, the compression spring 204 continues to be compressed, and the pressure ring 205 drives the connecting plate 206 and the guide column 207 to move toward the direction close to the positioning plate 203, and the guide column 207 moves in the guide hole. When the detection value of the pressure sensor in the pressure plate 305 reaches the required clamping force, the cylinder 202 stops contracting.

[0060] Then, the aluminum cap sheet is initially stamped and stretched into a cup body through the cooperation of the stamping assembly 4 and the stamping die 103. Specifically, the controller controls the extension of the hydraulic rod 402, and the hydraulic rod 402 drives the punching head 403 to move in the direction close to the stamping die 103. During this process, the punching head 403 stamps the middle position of the aluminum cap sheet to cause plastic deformation of the aluminum cap sheet, and a bent part appears on the aluminum cap sheet close to the pressure plate 305. Under the action of the hard stamping of the punching head 403, the annular sheet between the pressure plate 305 and the pressure ring 205 is separated and moves toward the direction of the stamping die 103, so that the punching head 403 and the side of the pressure plate 305 close to the punching head 403 squeeze the bent part inside and outside at the same time, so as to achieve the purpose of straightening the bent part, and finally the cup body is U-shaped.

[0061] In the above process, it is found that during the hard stamping process of the punch head 403, excessive tensile stress at the bending position will cause the material to become thinner, thereby causing the cup body to be uneven in thickness and affecting the straightness of the stretching. In the process of initially stamping and stretching the aluminum cap sheet into a cup body, the controller reduces the forward current passed into the electromagnet, that is, the magnetic attraction between the electromagnet inside the mounting seat 302 and the armature block inside the movable rod 304 is reduced. Under the joint action of the magnetic attraction and the adjusting spring 303, the pressure plate 305 drives the movable rod 304 and causes the movable rod 304 to move along The movable groove moves at a uniform speed toward the mounting seat 302, and the pressure plate 305 moves along the slide groove of the mounting frame 301, and the adjustment spring 303 is compressed. In this process, by simultaneously moving multiple pressure plates 305 toward the stamping die 103, the pressure ring 205 pushes the aluminum cap sheet to move along with the pressure plate 305, so that the force on the bent part of the aluminum cap sheet is balanced, avoiding the increase of tensile stress on the bent part when the punch head 403 moves toward the stamping die 103, resulting in thinning of the material and uneven thickness of the cup body.

[0062] However, during the process of the punching head 403 punching the aluminum cap sheet, the uneven distribution of the material of the aluminum cap sheet itself will cause different stretching degrees at different positions of the aluminum cap sheet. The pressure on the pressure plate 305 is monitored in real time by the pressure sensor, and then the pressure on the pressure plate 305 is detected by comparing the pressure sensors at different positions. If the pressure sensor at a certain position detects that the pressure on the pressure plate 305 is too large, it indicates that the material of the aluminum cap sheet itself is unevenly distributed and the stretching degree at this position is poor. At this time, the controller controls the electromagnet at this position to start and pass a reverse current, so that the mounting seat 30 Magnetic repulsion is generated between the electromagnet inside the 2 and the armature block inside the movable rod 304. Under the combined action of the magnetic repulsion and the adjusting spring 303, the pressure plate 305 drives the movable rod 304 to move away from the mounting seat 302, and the pressure plate 305 moves along the slide groove of the mounting frame 301, thereby increasing the supporting force of the pressure plate 305 at this position on the aluminum cap sheet and improving the stretching degree at this position. When the pressure sensor detects that the pressure on the pressure plate 305 is restored to a normal range, the controller controls the electromagnet at this position to recover and be consistent with the state of other electromagnets. No further details are given here.

[0063] In addition, when the annular sheet between the pressure plate 305 and the pressure ring 205 undergoes plastic deformation and slides away, and the punch head 403 and the side of the pressure plate 305 close to the punch head 403 simultaneously squeeze the bent portion inside and outside, that is, in the process of straightening the bent portion, the annular sheet will generate friction and heat with the pressure plate 305 and the pressure ring 205 respectively when it is detached, causing the temperature to rise, thereby changing the ductility of the aluminum cap sheet, that is, different temperatures at different positions cause different stretching degrees of the aluminum cap sheet. By detecting the temperature of the pressure plate 305 at different positions and comparing the temperatures of the pressure plate 305 at different positions, it is determined whether the local temperature is too high and the stretching degree is uneven. Due to the increase in temperature, the aluminum cap sheet material expands due to heat. In this process, the pressure on the pressure plate 305 at this position increases. That is, the pressure sensor is used to monitor the pressure on the pressure plate 305 in real time, and then the pressure change on the pressure plate 305 is calculated, thereby determining the temperature of the pressure plate 305 at this time.

[0064] If the pressure change on the pressure plate 305 at a certain position exceeds the standard value, it indicates that the temperature of the pressure plate 305 at this position is too high. The controller controls the electromagnet at this position to start and pass a reverse current, so that a magnetic repulsion force is generated between the electromagnet inside the mounting seat 302 and the armature block inside the movable rod 304. Under the joint action of the magnetic repulsion force and the adjusting spring 303, the pressure plate 305 drives the movable rod 304 to move away from the mounting seat 302, and the pressure plate 305 moves along the slide groove of the mounting frame 301, thereby increasing the tensile resistance of the pressure plate 305 at this position to the aluminum cap sheet, thereby ensuring that the degree of stretching at each position is consistent and improving the uniformity of product stretching.

[0065] It is worth noting that by increasing the tensile resistance of the pressure plate 305 to the aluminum cap sheet at this position, the strength of the material at this position can be improved, preventing the softening of the material due to local high temperature from affecting the molding quality, and avoiding the rebound phenomenon caused by high temperature, thereby improving the molding accuracy.

[0066] After the aluminum cap sheet is initially stamped and stretched into a cup body, the cup body is gradually thinned and formed by the cooperation of the stamping assembly 4 and the stretching die 104. Specifically, under the action of the hydraulic rod 402, the hydraulic rod 402 continues to drive the punch head 403 and the cup body to pass through multiple stretching dies 104 in sequence. During this process, the stretching diameter of the stretching die 104 gradually decreases, thereby further thinning and stretching the cup body, and finally the can body is formed. Such gradual stretching can ensure the uniformity of the material during the deformation process, reduce the risk of fracture due to local stress concentration, and improve the surface quality of the product. In addition, the wall thickness and diameter of the product can be controlled more accurately, thereby improving the utilization rate of the material and the consistency of the product.

[0067] In addition, in order to facilitate the stretching forming of the cup body, the stretching die 104 is heated by the heating sleeve 105, and the heating sleeve 105 is heated by an internal resistance wire. This is a prior art and will not be elaborated on here. The heating sleeve 105 heats the stretching die 104 to a suitable stretching temperature, which is convenient for improving the plasticity of the cup body and making it easier to stretch and deform it in the stretching die 104. This helps to reduce the resistance during the stretching process, improve production efficiency, and reduce the flow stress of the can material during the stretching process, thereby improving the stretching efficiency. Appropriate heating can improve the forming quality of the can during the stretching process and reduce the occurrence of defects such as cracks and wrinkles.

[0068] After the tank body is formed, the bottom of the tank body is stamped and formed by the cooperation of the stamping component 4 and the bottom forming component 5, so that the bottom of the tank body is a circular arched depression. Specifically, under the action of the hydraulic rod 402, the hydraulic rod 402 continues to drive the stamping head 403 and the tank body to move in the direction close to the bottom mold 505, that is, the stamping head 403 drives the tank body to enter the interior of the bottom mold 505 and squeezes the bottom mold 505. Under the action of the stamping head 403, the bottom mold 505, the buffer frame 504 and the limiting cylinder 503 are pushed to move in the direction close to the buffer plate 501. Finally, the bottom of the tank body is stamped and formed by the joint action of the stamping head 403 and the bottom mold 505. In this process, the reset spring 506 is compressed, and the limiting cylinder 503 moves along the limiting column 502. The purpose of buffering is achieved through the cooperation of structures such as the buffer frame 504, the limiting cylinder 503, the limiting column 502 and the reset spring 506.

[0069] In addition, after the bottom of the tank body is stamped and formed, the controller controls the hydraulic rod 402 to contract, and the hydraulic rod 402 drives the punching head 403 to move away from the bottom mold 505. At this time, the punching head 403 drives the tank body to move out of the bottom mold 505, and then the reset spring 506 returns to its original length. Under the action of the reset spring 506, the limit cylinder 503 drives the buffer frame 504 and the bottom mold 505 to move to the initial position together.

[0070] The present invention also provides a stretching method for an aluminum cap sheet, and the specific stretching method steps are as follows:

[0071] S1: First, the aluminum cap sheet to be processed is fixed by cooperating with the fixing component 2 and the adjusting component 3, and the blank holding force is adjusted accordingly according to the different thicknesses of the aluminum cap sheet;

[0072] S2: Then, under the action of the stamping assembly 4, the aluminum cap sheet passes through the stamping die 103 and the plurality of stretching dies 104 in sequence, so that the aluminum cap sheet undergoes plastic deformation and finally forms the desired can body;

[0073] S3: Finally, under the joint action of the stamping component 4 and the bottom forming component 5, the bottom of the can body is stamped so that the bottom of the can body is concave in a round arch shape, so that it can withstand greater pressure.

[0074] The present invention discloses an application of an aluminum cap sheet stretching device in the production of two-piece cans, and is specifically applied to the manufacture of a can body portion with a bottom in the production of two-piece cans. Specifically, the device processes the aluminum cap sheet through a stamping and stretching integrated molding process. Based on the principle of metal plastic deformation, during the stretching process, the aluminum material is subjected to the action of an external force and undergoes plastic deformation, thereby being processed into a desired shape and size. While ensuring the concentricity and straightness of the aluminum cap sheet and the mold, the device achieves precise control of the aluminum cap sheet stretching process by precisely controlling parameters such as the stretching force, the stretching speed, and the shape and size of the mold, thereby improving production quality and production efficiency. Therefore, in the production process of two-piece cans, the aluminum cap sheet stretching device is an indispensable and important equipment.

[0075] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0076] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An aluminum cap sheet stretching device, comprising a stretching assembly (1), the stretching assembly (1) comprising a frame (101), a stretching platform (102) being arranged above the frame (101), a stamping die (103) and a stretching die (104) being arranged above the stretching platform (102), characterized in that: A stamping assembly (4) and a bottom forming assembly (5) are respectively provided at both ends of the frame (101); a fixing assembly (2) and an adjusting assembly (3) are provided on one side of the stamping die (103); and the adjusting assembly (3) is arranged inside the fixing assembly (2); The fixing assembly (2) comprises a positioning plate (203), the positioning plate (203) being arranged on one side of the stamping die (103), a compression spring (204) being arranged on the surface of the positioning plate (203), and a compression ring (205) being arranged at one end of the compression spring (204) away from the positioning plate (203); Cylinders (202) are provided at four corners of the surface of the positioning plate (203); a fixing frame (201) is provided at one end of the cylinder (202) away from the positioning plate (203); and the fixing frame (201) is provided on one side of the stamping die (103); Connecting plates (206) are provided on both sides of the pressure ring (205); a guide column (207) is provided at one end of the connecting plate (206) close to the positioning plate (203); and a guide hole is provided at the position where the positioning plate (203) and the guide column (207) are connected; The adjustment component (3) comprises a mounting frame (301), a mounting seat (302) is arranged on one side of the mounting frame (301), a movable groove is provided on the surface of the mounting seat (302), and an adjustment spring (303) is arranged inside the movable groove, a movable rod (304) is arranged at one end of the adjustment spring (303) away from the movable groove, a pressure plate (305) is arranged on the side of the movable rod (304) away from the mounting seat (302), and a pressure sensor is arranged inside the pressure plate (305); An electromagnet is disposed inside the mounting seat (302), an armature block is disposed inside the movable rod (304), and the armature block is disposed at one end of the movable rod (304) close to the adjustment spring (303).

2. The aluminum cap sheet stretching device according to claim 1 is characterized in that: The stamping die (103) is arranged at one end of the stretching platform (102) close to the stamping component (4), and the stretching die (104) is arranged at a side of the stamping die (103) away from the stamping component (4); There are a plurality of stretching dies (104), and the plurality of stretching dies (104) are arranged on the stretching platform (102) at equal intervals, and the stretching diameter of the stretching die (104) close to the stamping die (103) is greater than the stretching diameter of the stretching die (104) far from the stamping die (103).

3. The aluminum cap sheet stretching device according to claim 2 is characterized in that: A heating sleeve (105) is provided on the outer surface of the stretching die (104), a positioning frame (106) is provided below the stamping die (103), the positioning frame (106) is arranged on the surface of the stretching platform (102), and clamping plates (107) are provided on both sides of the stretching die (104), and a clamping groove is provided at the position where the clamping plate (107) is connected to the stretching platform (102).

4. The aluminum cap sheet stretching device according to claim 1, characterized in that: There are a plurality of mounting seats (302), and the plurality of mounting seats (302) are arranged in a ring shape on the surface of the mounting frame (301). A sliding groove is provided at a position where the mounting frame (301) is connected to the pressure plate (305), and the movable rod (304) is adapted to the movable groove.

5. The aluminum cap sheet stretching device according to claim 1, characterized in that: The punching assembly (4) comprises a fixing seat (401), the fixing seat (401) being arranged at one end of the frame (101), a hydraulic rod (402) being arranged at the center of the surface of the fixing seat (401), a punching head (403) being arranged at one end of the output shaft of the hydraulic rod (402), and a plurality of supporting seats (404) being arranged at equal intervals below the hydraulic rod (402); One end of the support seat (404) away from the hydraulic rod (402) is connected to the frame (101), and an arc-shaped groove is formed at one end of the support seat (404) away from the frame (101), and a buffer pad is provided inside the arc-shaped groove.

6. The aluminum cap sheet stretching device according to claim 1, characterized in that: The bottom forming assembly (5) comprises a buffer plate (501), the buffer plate (501) being arranged on the frame (101), a limiting column (502) being arranged at the center position of the surface of the buffer plate (501), a limiting cylinder (503) being arranged at one end of the limiting column (502) away from the buffer plate (501), a buffer frame (504) being arranged at one end of the limiting cylinder (503) away from the limiting column (502), and a bottom mold (505) being arranged inside the buffer frame (504).

7. The aluminum cap sheet stretching device according to claim 6, characterized in that: A return spring (506) is disposed on the outer surface of the limit column (502), one end of the return spring (506) is fixedly connected to the buffer plate (501), one end of the return spring (506) away from the buffer plate (501) is fixedly connected to the limit cylinder (503), and a limit groove is provided at the position where the limit cylinder (503) is connected to the limit column (502).

8. A method for stretching an aluminum cap sheet, the method being implemented by using the aluminum cap sheet stretching device as claimed in claim 1, characterized in that: The specific stretching method steps are as follows: S1: First, the aluminum cap sheet to be processed is fixed by cooperating with the fixing component (2) and the adjusting component (3), and the blank holding force is adjusted accordingly according to the different thicknesses of the aluminum cap sheet; S2: Then, under the action of the stamping assembly (4), the aluminum cap sheet is passed through the stamping die (103) and a plurality of stretching dies (104) in sequence, so that the aluminum cap sheet undergoes plastic deformation and finally forms the desired can body; S3: Finally, under the joint action of the punching component (4) and the bottom forming component (5), the bottom of the can body is punched, so that the bottom of the can body is concave in a round arch shape, so that it can withstand greater pressure.

9. Use of the aluminum cap sheet stretching device as described in any one of claims 1 to 7 in the production of two-piece cans.

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