A compound type stress relief device and method for aluminum plate

Abstract

The application discloses a composite stress relieving device for aluminum plate in the field of plate flattening, which comprises a roller flattening machine and a stretching mechanism. The roller flattening machine is formed by the staggered arrangement of upper roller groups and lower roller groups into an S-shaped shaping channel for repeatedly bending the aluminum plate. The roller shafts rotate synchronously through a driving mechanism and convey the aluminum plate to advance. The stretching mechanism has clamping jaws and a hydraulic driving mechanism to exert an axial traction force on the aluminum plate. The traction linear velocity of the stretching mechanism is configured to be greater than the linear velocity of the roller shafts in the roller flattening machine, so as to form a stable speed difference between them to force the aluminum plate to plastically extend in the S-shaped shaping channel along the axial direction. Through the combined action of the two plastic deformations, the overall cross section of the aluminum plate is in a plastic stress state exceeding the yield limit, thereby realizing the synchronous and efficient elimination of the in-plane and thickness direction residual stress of the aluminum plate. The technical scheme effectively integrates the stress relieving process, and significantly improves the stress relieving efficiency.

Description

Technical Field

[0001] This invention relates to the field of sheet metal leveling, and more specifically to a composite stress-relieving device and method for aluminum sheets. Background Technology

[0002] During the rolling, heat treatment and subsequent processing of aluminum sheets and aluminum alloy plates, complex residual stress fields are formed inside. These stresses are the main cause of sheet warping, dimensional instability and precision defects.

[0003] Traditional stress relief processes typically rely on two independent steps: roller leveling and tension leveling.

[0004] First, roller leveling uses staggered roller sets to repeatedly bend the sheet material, primarily to eliminate uneven residual stress in the thickness direction, but its effect on eliminating in-plane stress is limited. Subsequently, the sheet material is transferred to the next station for tensile leveling. This step applies axial tensile stress exceeding the yield limit to the sheet material using fixtures, primarily to eliminate or stabilize in-plane residual stress.

[0005] Because this process must be completed in two steps on two sets of equipment, it presents several significant technical problems. Firstly, it is inefficient, as the sheet metal needs to be transferred and clamped between two large sets of equipment, increasing operation time and the overall processing cycle.

[0006] Secondly, there are issues of residual stress and secondary stress. No single method can completely eliminate stress in all directions. Furthermore, after roller leveling, subsequent stretching steps may cause new interference with the stress distribution in the thickness direction of the sheet or fail to completely release the stress.

[0007] Finally, this step-by-step process requires two separate sets of large, space-consuming equipment, resulting in high equipment investment costs. Summary of the Invention

[0008] The purpose of this invention is to provide a composite stress-relieving device and method for aluminum plates, so as to solve the problem of low efficiency caused by the reliance on two independent sets of equipment, roller leveling and stretch leveling, in the existing aluminum plate stress-relieving process.

[0009] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0010] According to one aspect of this disclosure, a composite stress-relieving device for aluminum plates is provided, comprising a roller leveler and a stretching mechanism arranged in sequence.

[0011] A roller leveling machine includes an upper roller group, a lower roller group, and a drive mechanism for driving the upper roller group and / or the lower roller group to rotate synchronously to convey an aluminum plate forward by friction. The upper roller group and the lower roller group are staggered in the conveying direction of the aluminum plate to form an S-shaped shaping channel for repeatedly bending the aluminum plate to release stress.

[0012] The stretching mechanism has a clamping jaw for holding an aluminum plate emerging from an S-shaped shaping channel and a hydraulic drive mechanism for driving the clamping jaw to translate. The hydraulic drive mechanism applies a traction force to the aluminum plate through the clamping jaw.

[0013] Among them, the traction linear speed of the stretching mechanism is greater than the linear speed of the roller shaft in the roller leveling machine to form a speed difference. The speed difference causes the traction force to force the aluminum plate to be plastically stretched along the axial direction in the S-shaped shaping channel.

[0014] The combined effect of axial plastic elongation and repeated bending of the S-shaped plastic channel puts the overall cross-section of the aluminum plate in a plastic stress state exceeding the yield limit, thereby achieving the simultaneous elimination of residual stress in the in-plane and thickness directions of the aluminum plate.

[0015] Furthermore, an induction heating mechanism is provided at the front end of the roller leveler. The induction heating mechanism has a heating channel for the aluminum plate to pass through and enter the S-shaped shaping channel. The aluminum plate is electromagnetically heated to a preset temperature in the heating channel to improve the plasticity of the aluminum plate. The roller leveler is used to level the aluminum plate when it is at the preset temperature.

[0016] Furthermore, each roller in the upper and lower roller groups has an axially extending heat exchange chamber inside, which is filled with a heat-conducting medium.

[0017] A heat exchange tube is installed in the heat exchange chamber. The heat exchange tube has a refrigerant inlet and a refrigerant outlet. Both the refrigerant inlet and the refrigerant outlet extend outward from one axial end of the roller into the heat exchange chamber. A refrigerant flows inside the heat exchange tube.

[0018] The refrigerant inlet and refrigerant outlet are connected to a refrigerant circulation system, which circulates the refrigerant in the heat exchange tubes through the refrigerant inlet and refrigerant outlet.

[0019] Furthermore, the refrigerant circulation system has independent circulation units matching the number of rollers and a controller, each independent circulation unit including:

[0020] A first interface for connecting the refrigerant inlet to the corresponding roller shaft;

[0021] A second interface for connecting the refrigerant outlet of the corresponding roller shaft;

[0022] A regulating pump used to drive the circulation of the cold medium and control the flow rate;

[0023] A thermocouple used to detect the real-time temperature of the roller shaft;

[0024] All regulating pumps and thermocouples are electrically connected to the controller. The controller receives the detection results of all thermocouples and independently controls the corresponding regulating pumps to maintain the working temperature of all rollers within a preset temperature range.

[0025] Furthermore, the thermocouple is a contact sensor, with its probe tip in close contact with the surface of the roller shaft that does not contact the aluminum plate on the circumference.

[0026] Furthermore, the refrigerant inlet and refrigerant outlet are located at both ends of the heat exchange tube in the axial direction, and the ends of the rollers are provided with rotary joints for the refrigerant inlet or refrigerant outlet to pass outward through the heat exchange chamber. The rotary joints make the refrigerant inlet, refrigerant outlet and rollers coaxial.

[0027] Furthermore, each roller has a hollow support shaft at its axial end for connecting the drive mechanism, and a rotary joint is fitted inside the hollow support shaft to provide dynamic sealing for both ends of the heat exchange chamber.

[0028] Furthermore, the drive mechanism includes:

[0029] The number of main gears matches the number of rollers in the upper or lower roller group. Each main gear is coaxial and fixedly sleeved on the outside of the hollow support shaft of the corresponding roller.

[0030] There are several idler gears, and each idler gear meshes with two adjacent main gears at the same time.

[0031] A rotary power source, used to apply rotational force to one of the main gears;

[0032] The number of idler gears is configured such that, driven by a rotary power source, all main gears can rotate synchronously in the same direction.

[0033] Furthermore, there are two sets of drive mechanisms, which drive all the rollers of the upper roller group and all the rollers of the lower roller group to rotate in the same direction, respectively.

[0034] The upper roller group and the lower roller group have opposite rotation directions.

[0035] According to another aspect of this disclosure, a composite stress relief method is provided, employing the composite stress relief device for aluminum plates as described above, the method comprising the following steps:

[0036] S1, Preheating and Plasticizing: The aluminum plate is fed into the heating channel of the induction heating mechanism, and the temperature of the aluminum plate is brought up to the preset temperature range by electromagnetic induction heating to improve the plasticity of the aluminum plate.

[0037] S2, Roller leveling and conveying: The upper roller group and / or lower roller group of the drive roller leveler rotate synchronously, and the aluminum plate is conveyed forward by friction, so that the aluminum plate enters the S-shaped shaping channel and generates repeated bending action to eliminate the residual stress in the thickness direction of the aluminum plate until its head end extends out of the roller leveler.

[0038] S3, Clamping Traction and Differential Speed: The clamping claws of the stretching mechanism clamp the head end of the aluminum plate. The output of the hydraulic drive mechanism drives the clamping claws to move, so that the traction linear speed of the stretching mechanism is greater than the linear speed of the roller in the roller leveling machine, forming a stable speed difference. The speed difference forces the aluminum plate to undergo axial plastic extension in the S-shaped shaping channel to eliminate the in-plane residual stress of the aluminum plate.

[0039] In S2 and S3, the controller continuously receives the thermocouple detection results from the roller surface. Based on these results, the controller adjusts the flow output of each independent circulation unit in the refrigerant circulation system in real time to maintain the stability of the roller gap in the S-shaped shaping channel.

[0040] The beneficial effects of this invention are:

[0041] This invention connects a tensioning mechanism in series after a roller leveler and sets the traction linear speed of the tensioning mechanism to be greater than the linear speed of the roller leveler's roller shaft to form a stable speed difference. This speed difference forces the aluminum plate to bear continuous axial tensile plastic stress in the S-shaped shaping channel. This stress, together with the repeated bending plastic strain generated by the roller shaft, makes the entire cross section of the aluminum plate in a plastic stress state exceeding the yield limit at the same station and at the same time, effectively simplifying the traditional process flow. Attached Figure Description

[0042] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the planar structure composition of an embodiment of the present invention;

[0044] Figure 2 This is a schematic diagram of the internal structure of the roller shaft and the thermocouple in an embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of the planar structure of the roller shaft according to an embodiment of the present invention;

[0046] Figure 4 This is a schematic diagram of the system composition of the refrigerant circulation system according to an embodiment of the present invention;

[0047] The labels in the diagram represent the following: 1-Upper roller group; 2-Lower roller group; 3-S-shaped shaping channel; 4-Clamping claw; 5-Induction heating mechanism; 5a-Heating channel; 6-Roller shaft; 6a-Heat exchange chamber; 6b-Hollow support shaft; 7-Heat exchange tube; 7a-Refrigerant inlet; 7b-Refrigerant outlet; 8-Independent circulation unit; 8a-First interface; 8b-Second interface; 8c-Regulating pump; 8d-Thermocouple; 9-Rotary joint; 10-Main gear; 11-Idle gear; 12-Aluminum plate; 13-Diverter; 14-Cooling unit. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] This embodiment provides a composite stress-relieving device for aluminum plates, which aims to solve the problem of low efficiency caused by the reliance on two independent sets of equipment, roller leveling and stretch leveling, in the existing aluminum plate stress-relieving process.

[0050] Specifically, refer to Figures 1 to 4 As shown, this composite stress relief device includes a roller leveling machine and a stretching mechanism arranged in sequence.

[0051] The roller leveling machine includes an upper roller group 1, a lower roller group 2, and a drive mechanism for driving the upper roller group 1 and / or the lower roller group 2 to rotate synchronously. The upper roller group 1 and the lower roller group 2 are staggered in the conveying direction of the aluminum plate 12 to form an S-shaped shaping channel 3 for repeatedly bending the aluminum plate 12 to release stress. The drive mechanism conveys the aluminum plate 12 forward by friction.

[0052] The stretching mechanism has a clamping claw 4 for holding the aluminum plate 12 that comes out of the S-shaped shaping channel 3 and a hydraulic drive mechanism for driving the clamping claw 4 to translate; the hydraulic drive mechanism applies a traction force to the aluminum plate 12 through the clamping claw 4.

[0053] In this device, the traction linear velocity of the stretching mechanism is greater than the linear velocity of the roller 6 in the roller leveler, thus creating a speed difference. This speed difference forces the aluminum plate 12 to undergo axial plastic elongation in the S-shaped shaping channel 3. This axial plastic elongation, combined with the repeated bending action of the S-shaped shaping channel 3, causes the overall cross-section of the aluminum plate 12 to be in a plastic stress state exceeding the yield limit, thereby achieving the simultaneous elimination of residual stress in the in-plane and thickness directions of the aluminum plate 12.

[0054] The principle of composite stress relief in this embodiment is: the traction speed V applied by the tensioning mechanism 牵引 Conveying speed V of roller 6 辊轴 The stable speed difference formed between them forces the sheet to undergo axial plastic elongation within the S-shaped shaping channel 3.

[0055] This plastic extension (to eliminate in-plane stress) is synchronously superimposed with the repeated bending action of the roller 6 provided by the S-shaped shaping channel 3 (to eliminate thickness stress), ensuring that the overall cross section of the plate reaches and exceeds the yield limit, thereby releasing residual stress in all directions.

[0056] Although the above-mentioned solution can achieve composite stress relief, plastic deformation of aluminum plate 12 (especially high-strength or thick aluminum plate 12) at room temperature requires huge force, which not only places high power requirements on the drive mechanism, but also poses a severe challenge to the load-bearing capacity of roller 6.

[0057] Therefore, an induction heating mechanism 5 is provided at the front end of the roller leveling machine. The induction heating mechanism 5 has a heating channel 5a for the aluminum plate 12 to pass through and enter the S-shaped shaping channel 3. The aluminum plate 12 is electromagnetically heated to a preset temperature in the heating channel 5a.

[0058] The roller leveler is used to level the aluminum plate 12 at the preset temperature. Heating increases the plasticity of the aluminum plate 12 (i.e., reduces its yield strength), making it easier to reach the plastic stress state during subsequent "S"-shaped bending and axial stretching processes, thereby reducing the total power and mechanical load required by the equipment.

[0059] However, after the introduction of preheating, the high-temperature aluminum plate 12 will continuously transfer heat to the rollers 6 of the upper roller group 1 and the lower roller group 2 when passing through the S-shaped shaping channel 3. This will cause the rollers 6 to thermally expand and deform, thereby changing the roller gap of the S-shaped shaping channel 3. The instability of the gap will directly destroy the uniformity of the leveling accuracy and the composite stress relief effect.

[0060] To address the thermal deformation problem of the rollers 6, each roller 6 in the upper roller group 1 and the lower roller group 2 has an axially extending heat exchange chamber 6a inside. The heat exchange chamber 6a is filled with a heat-conducting medium, and a heat exchange tube 7 is installed inside the heat exchange chamber 6a. The heat exchange tube 7 has a refrigerant inlet 7a and a refrigerant outlet 7b. Both the refrigerant inlet 7a and the refrigerant outlet 7b extend outward from one axial end of the roller 6 into the heat exchange chamber 6a, and a refrigerant medium flows inside the heat exchange tube 7.

[0061] The refrigerant inlet 7a and refrigerant outlet 7b are connected to a refrigerant circulation system. The refrigerant circulation system circulates the refrigerant in the heat exchange tube 7 through the refrigerant inlet 7a and refrigerant outlet 7b, thereby removing the heat accumulated in the roller 6 and maintaining its temperature stability.

[0062] This design also brings about a synergistic technical effect: conventional leveling rollers 6 are usually thicker or even solid in order to ensure strength. If internal cooling is to be introduced, a larger heat exchange chamber 6a must be set up, which will reduce the structural strength of the roller 6 compared with the traditional solid roller 6.

[0063] However, in this embodiment, since induction heating has increased the plasticity (reduced the strength) of the aluminum plate 12 material, the force exerted by the plate on the roller 6 in the S-shaped shaping channel 3 is also reduced. Therefore, the hollow roller 6 with reduced strength can still meet the load requirements for leveling. That is, the pre-induction heating scheme achieves better stress relief while also reducing the structural strength requirements of the roller 6.

[0064] However, in actual operation, the heat load on rollers 6 at different locations (such as the inlet and outlet) is different. If all rollers 6 share a common cooling circuit, it will be impossible to achieve precise temperature control for each roller 6. Some rollers 6 may be overheated or undercooled, which will also cause the roller gap of the S-shaped shaping channel 3 to become unstable.

[0065] Based on this, the refrigerant circulation system has 6 independent circulation units 8 matching rollers and a controller, each independent circulation unit 8 including:

[0066] A first interface 8a that connects to the refrigerant inlet 7a of the corresponding roller 6;

[0067] A second interface 8b is connected to the refrigerant outlet 7b of the corresponding roller 6;

[0068] A regulating pump 8c for driving the circulation of the refrigerant and controlling its flow rate; and,

[0069] A thermocouple 8d is used to detect the real-time temperature of roller 6.

[0070] All regulating pumps 8c and thermocouples 8d are electrically connected to the controller. The controller receives the detection results of all thermocouples 8d and independently controls the corresponding regulating pumps 8c (e.g., adjusting their pump speed to change the refrigerant flow) to maintain the working temperature of all rollers 6 within a preset temperature range, ultimately ensuring the stability of the roller gap of the S-shaped shaping channel 3.

[0071] In addition, to meet the requirements of refrigerant circulation cooling and multi-channel independent flow control, the refrigerant circulation system is externally equipped with a cooling unit 14 (e.g., a chiller or a high-efficiency heat exchanger). This cooling unit is used to receive and process the high-temperature refrigerant circulating from the heat exchange tubes 7 of the roller 6, and reduce its temperature through heat exchange.

[0072] Specifically, the refrigerant circulation system is structurally equipped with a distributor 13. The cooled low-temperature refrigerant is fed into the distributor 13 by the cooling unit 14. The distributor 13 distributes and guides the low-temperature refrigerant to the first interface 8a of each independent circulation unit through internal flow channels and branch interfaces. The first interface 8a is connected to the water pump inlet of the corresponding regulating pump 8c, while the water pump outlet of the regulating pump 8c is connected to the refrigerant inlet 7a of the corresponding roller 6.

[0073] After receiving the low-temperature refrigerant, the regulating pump 8c sends it to the refrigerant inlet 7a of the corresponding roller 6 according to the controller command, so as to realize the independent regulation of the flow rate. The high-temperature refrigerant, after heat exchange and heating, flows out from the refrigerant outlet 7b of the roller 6 and re-enters the collection side of the distributor 13 through the second interface 8b.

[0074] The distributor guides the collected high-temperature refrigerant back to the external cooling unit for cooling. This parallel branching design ensures that the flow regulation and temperature control of each roller 6 are independent of each other, achieving high-precision independent temperature control.

[0075] The control accuracy of the above scheme is highly dependent on the accuracy and real-time performance of the temperature detected by thermocouple 8d. If non-contact measurement (such as infrared temperature measurement) is used, it is easily affected by water vapor, oil stains or changes in the emissivity of the roller surface. If the sensor is placed in non-critical parts such as bearings, the temperature difference between the measuring point and the working surface of the roller 6 is large, resulting in serious lag and failing to accurately reflect the roller surface temperature.

[0076] Therefore, thermocouple 8d is a contact sensor, with its probe end in close contact with the surface of roller shaft 6 that does not contact aluminum plate 12 on the circumference, in order to obtain temperature data that is closest to the actual working condition.

[0077] Furthermore, in order to connect the stationary refrigerant circulation system piping to the high-speed rotating roller 6 (and its internal heat exchange tubes 7) and ensure long-term reliability under high pressure and high temperature, and to prevent leakage, this embodiment places the refrigerant inlet 7a and the refrigerant outlet 7b at opposite ends of the heat exchange tubes 7 in the axial direction. Additionally, each end of the roller 6 is equipped with a rotary joint 9 for allowing the refrigerant inlet 7a or the refrigerant outlet 7b to pass outward through the heat exchange chamber 6a.

[0078] The rotary joint 9 makes the refrigerant inlet 7a, refrigerant outlet 7b and roller 6 coaxial, allowing the roller 6 to rotate while the refrigerant pipeline remains stationary and completes fluid transport.

[0079] Although the rotary joint 9 solves the fluid sealing problem, the pressure on the roller 6 during the leveling process is enormous. The drive mechanism needs to transmit huge torque to the roller 6, and the connection stability between the roller 6 and the rotary joint 9 is also tested. If a traditional split connection is used (for example, the rotary joint 9 is assembled at the end of the roller 6 like a bearing), the connection rigidity is insufficient under such high load conditions, and misalignment or damage is likely to occur.

[0080] To enhance the connection stability of the rollers 6, each roller 6 has a hollow support shaft 6b at its axial end for connecting the drive mechanism (the hollow support shaft 6b is preferably integrally formed or welded to the end of the roller 6). The rotary joint 9 is embedded in the inner side of the hollow support shaft 6b and is used to dynamically seal the axial ends of the heat exchange chamber 6a.

[0081] This design, which "embeds" the rotary joint 9 into the integrated hollow support shaft 6b, significantly improves stability under high pressure compared to the separate connection of the two.

[0082] In order to maintain a stable speed difference with the stretching mechanism, all rollers 6 in the same roller group (e.g., upper roller group 1 or lower roller group 2) must achieve strict synchronous rotation. If multiple motors are used for independent drive, the control complexity is high and it is difficult to guarantee the speed synchronization.

[0083] Therefore, the drive mechanism includes:

[0084] The number of main gears 10 matches the number of roller shafts 6 in the upper roller group 1 or the lower roller group 2. Each main gear 10 is coaxial and fixedly sleeved on the outside of the hollow support shaft 6b of the corresponding roller shaft 6.

[0085] The idler gears 11 are numerous, and each idler gear 11 simultaneously meshes with two adjacent main gears 10; and a rotational power source is used to apply rotational force to one of the main gears 10.

[0086] The number of idler gears 11 is configured to drive all main gears 10 to rotate in the same direction synchronously under the drive of a rotary power source. This gear system structure ensures that all roller shafts 6 of the same roller group rotate at the same linear speed.

[0087] The aforementioned drive mechanism ensures synchronization within the "single set" of rollers 6 (such as the upper roller set 1), but for the aluminum plate 12 to advance in the S-shaped shaping channel 3, the upper roller set 1 and the lower roller set 2 must rotate relative to each other and jointly apply frictional conveying force to the aluminum plate 12.

[0088] Therefore, there are two sets of drive mechanisms. The two sets of drive mechanisms drive all the rollers 6 of the upper roller group 1 and all the rollers 6 of the lower roller group 2 to rotate in the same direction (i.e., all the rollers 6 of the upper roller group 1 and all the rollers 6 of the lower roller group 2 rotate in the same direction). The rollers 6 of the upper roller group 1 and the rollers 6 of the lower roller group 2 rotate in opposite directions to clamp and transport the aluminum plate 12 forward.

[0089] This embodiment also provides a composite stress relief method based on the aforementioned device (specifically, a device with a precision temperature control system), which includes the following steps:

[0090] S1, Preheating and Plasticizing: The aluminum plate 12 is fed into the heating channel 5a of the induction heating mechanism 5, and the temperature of the aluminum plate 12 is brought up to the preset temperature range by electromagnetic induction heating to improve the plasticity of the aluminum plate 12.

[0091] S2, Roller leveling and conveying: The upper roller group 1 and / or lower roller group 2 of the drive roller leveler rotate synchronously, and convey the aluminum plate 12 forward through friction, so that the aluminum plate 12 enters the S-shaped shaping channel 3, generating repeated bending action to eliminate the residual stress in the thickness direction of the aluminum plate 12 until its head end extends out of the roller leveler.

[0092] S3, Clamping Traction and Differential Speed: The clamping claws 4 of the stretching mechanism clamp the head end of the aluminum plate 12. The output of the hydraulic drive mechanism drives the clamping claws 4 to move, making the traction linear speed of the stretching mechanism greater than the linear speed of the roller shaft 6 in the roller leveler, forming a stable speed difference. This speed difference forces the aluminum plate 12 to undergo axial plastic extension in the S-shaped shaping channel 3, thereby eliminating the in-plane residual stress of the aluminum plate 12.

[0093] Throughout steps S2 and S3, the controller continuously receives the detection results from the thermocouple 8d on the surface of the roller 6. Based on these results, the controller corrects the flow output of each independent circulation unit 8 in the refrigerant circulation system in real time (e.g., adjusting the speed of the regulating pump 8c) to maintain the stability of the roller gap in the "S" shaped shaping channel.

[0094] In the aforementioned composite stress-relief process, achieving stable and safe plastic elongation is crucial. Therefore, this embodiment employs stress-strain dual closed-loop feedback control to manage the speed difference between the roller leveler and the stretching mechanism.

[0095] The control system monitors the axial tensile force F borne by the aluminum plate 12 in real time by installing a high-precision tension sensor on the hydraulic drive system of the tensioning mechanism. 拉 Meanwhile, both the roller shaft 6 of the roller leveler and the drive end of the tensioning mechanism are equipped with high-precision encoders or speed measuring elements for real-time feedback of the linear speed V of the roller shaft 6. 辊轴 and traction line speed V 牵引The goal of the controller is to set the optimal target plastic elongation (typically between 0.5% and 2.0%) based on the alloy and thickness of the aluminum plate 12.

[0096] The controller continuously utilizes V 辊轴 Calculate the target traction speed V to be maintained. target And according to V 牵引 With V target The deviation between the two values ​​is adjusted in real time to regulate the output of the hydraulic drive mechanism, thereby ensuring that the actual elongation is stable at the target value and achieving closed-loop control of constant plastic elongation.

[0097] In addition, to ensure the board is not torn, the system also has a high-priority safety protection mechanism. The controller will monitor the F value in real time. 拉 With the preset safety tensile force threshold F Safety (Typically 60% to 75% of the tensile strength of aluminum plate 12) is compared. Once F 拉 Reaching or exceeding F Safety The controller will immediately override the speed control logic, rapidly reducing the output power of the hydraulic drive mechanism and forcing V... 牵引 Equal to or slightly less than V 辊轴 This eliminates speed differences, thereby rapidly releasing accumulated strain, effectively preventing plate breakage, and ensuring the safe operation of equipment and processes.

[0098] Finally, the heat-conducting medium (such as heat-conducting oil or special coolant) in the heat exchange chamber 6a inside the roller in this embodiment will continuously absorb heat from the high-temperature aluminum plate 12 during operation. Since the chamber space is relatively closed, when the temperature of the heat-conducting medium rises, its volume will undergo significant thermal expansion.

[0099] If this volume expansion is not controlled, it will cause the pressure inside the heat exchange chamber 6a to rise sharply. Once the pressure exceeds the pressure resistance limit designed inside the roller, it will cause leakage or failure of the sealing components (especially the rotary joint).

[0100] To effectively eliminate the above-mentioned drawbacks, this embodiment provides a high-temperature resistant airbag in the heat exchange chamber 6a of each roller. The airbag is pre-filled with an inert gas (such as nitrogen) at a certain pressure, and its function is to serve as a flexible volume compensation unit.

[0101] When the heat transfer medium expands in volume due to heat, the air bladder absorbs the excess volume by compressing the inert gas inside, thereby stabilizing the system pressure within the heat exchange chamber 6a within a safe range. Conversely, when the medium temperature decreases, the gas inside the air bladder expands, ensuring the heat exchange chamber 6a is fully filled.

[0102] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered as falling within the scope of protection of the embodiments of the present invention.

Claims

1. A composite stress-relieving device for aluminum plates, characterized in that, This includes a roller leveling machine and a stretching mechanism arranged in sequence; The roller leveling machine includes an upper roller group (1), a lower roller group (2), and a drive mechanism for driving the upper roller group (1) and / or the lower roller group (2) to rotate synchronously to convey the aluminum plate (12) forward by friction. The upper roller group (1) and the lower roller group (2) are staggered in the conveying direction of the aluminum plate (12) to form an S-shaped shaping channel (3) for repeatedly bending the aluminum plate (12) to release stress. The stretching mechanism has a clamping claw (4) for clamping the aluminum plate (12) coming out of the S-shaped shaping channel (3) and a hydraulic drive mechanism for driving the clamping claw (4) to translate, the hydraulic drive mechanism applying a traction force to the aluminum plate (12) through the clamping claw (4); Wherein, the traction linear speed of the stretching mechanism is greater than the linear speed of the roller shaft (6) in the roller leveling machine to form a speed difference, the speed difference causing the traction force to force the aluminum plate (12) to be plastically stretched along the axial direction in the S-shaped shaping channel (3). The axial plastic extension and the repeated bending of the S-shaped shaping channel (3) work together to make the overall cross section of the aluminum plate (12) be in a plastic stress state exceeding the yield limit, so as to realize the synchronous elimination of residual stress in the plane and thickness direction of the aluminum plate (12); an induction heating mechanism (5) is provided at the front end of the roller leveling machine. The induction heating mechanism (5) has a heating channel (5a) for the aluminum plate (12) to pass through and enter the S-shaped shaping channel (3). The aluminum plate (12) is electromagnetically induction heated to a preset temperature in the heating channel (5a) to improve the plasticity of the aluminum plate (12). The roller leveling machine is used to level the aluminum plate (12) when it is in the preset temperature state; all the rollers (6) in the upper roller group (1) and the lower roller group (2) have an axially extending heat exchange chamber (6a) inside. The heat exchange chamber (6a) is filled with a heat-conducting medium. A heat exchange tube (7) is provided in the heat exchange chamber (6a). The heat exchange tube (7) has a refrigerant inlet (7a) and a refrigerant outlet (7b). The refrigerant inlet (7a) and the refrigerant outlet (7b) both extend outward from one axial end of the roller (6) into the heat exchange chamber (6a). A refrigerant flows in the heat exchange tube (7). The refrigerant inlet (7a) and the refrigerant outlet (7b) are connected to a refrigerant circulation system, which circulates the refrigerant in the heat exchange tube (7) through the refrigerant inlet (7a) and the refrigerant outlet (7b); the refrigerant circulation system has independent circulation units (8) matching the number of rollers (6) and a controller, each independent circulation unit (8) including: A first interface (8a) of the refrigerant inlet (7a) of the corresponding roller (6); A second interface (8b) is connected to the refrigerant outlet (7b) of the corresponding roller (6). A regulating pump (8c) for driving the circulation of the cold medium and controlling the flow rate. A thermocouple (8d) for detecting the real-time temperature of the roller (6); All the regulating pumps (8c) and thermocouples (8d) are electrically connected to the controller. The controller receives the detection results of all thermocouples (8d) and independently controls the corresponding regulating pumps (8c) to maintain the working temperature of all rollers (6) within a preset temperature range.

2. The composite stress-relieving device for aluminum plates according to claim 1, characterized in that, The thermocouple (8d) is a contact sensor, and its probe end is in close contact with the surface of the roller (6) that is not in contact with the aluminum plate (12) on the circumference.

3. The composite stress-relieving device for aluminum plates according to claim 1, characterized in that, The refrigerant inlet (7a) and the refrigerant outlet (7b) are located at both ends of the heat exchange tube (7) in the axial direction, and the ends of the roller (6) are provided with rotary joints (9) for the refrigerant inlet (7a) or the refrigerant outlet (7b) to pass outward through the heat exchange chamber (6a). The rotary joints (9) make the refrigerant inlet (7a), the refrigerant outlet (7b) and the roller (6) coaxial.

4. A composite stress-relieving device for aluminum plates according to claim 3, characterized in that, Each of the rollers (6) has a hollow support shaft (6b) at its axial end for connecting the drive mechanism. The rotary joint (9) is fitted inside the hollow support shaft (6b) and is used to dynamically seal both ends of the heat exchange chamber (6a).

5. A composite stress-relieving device for aluminum plates according to claim 4, characterized in that, The drive mechanism includes: The number of main gears (10) matches the number of roller shafts (6) in the upper roller group (1) or the lower roller group (2). Each main gear (10) is coaxial and fixedly sleeved on the outside of the hollow support shaft (6b) of the corresponding roller shaft (6). There are several idler gears (11), and each idler gear (11) meshes with two adjacent main gears (10) at the same time. A rotational power source for applying rotational force to one of the main gears (10); The number of idler gears (11) is configured such that, under the drive of the rotational power source, all main gears (10) can be driven to rotate in the same direction synchronously.

6. A composite stress-relieving device for aluminum plates according to claim 5, characterized in that, The number of driving mechanisms is two sets, and the two sets of driving mechanisms drive all the roller shafts (6) of the upper roller group (1) and all the roller shafts (6) of the lower roller group (2) to rotate in the same direction; The roller shafts (6) of the upper roller group (1) and the roller shafts (6) of the lower roller group (2) rotate in opposite directions.

7. A composite stress relief method based on the device of claim 1, characterized in that, The method includes the following steps: S1, Preheating and Plasticizing: The aluminum plate (12) is fed into the heating channel (5a) of the induction heating mechanism (5), and the temperature of the aluminum plate (12) is brought to a preset temperature range by electromagnetic induction heating, so as to improve the plasticity of the aluminum plate (12). S2, Roller leveling and conveying: Drive the upper roller group (1) and / or lower roller group (2) of the roller leveling machine to rotate synchronously, and convey the aluminum plate (12) forward by friction, so that the aluminum plate (12) enters the S-shaped shaping channel (3) and generates repeated bending action to eliminate the residual stress in the thickness direction of the aluminum plate (12) until its head end extends out of the roller leveling machine; S3, Clamping Traction and Differential Speed: The clamping claw (4) of the stretching mechanism clamps the head end of the aluminum plate (12). The output of the hydraulic drive mechanism drives the clamping claw (4) to move, so that the traction linear speed of the stretching mechanism is greater than the linear speed of the roller shaft (6) in the roller leveling machine, forming a stable speed difference. The speed difference forces the aluminum plate (12) to undergo axial plastic extension in the S-shaped shaping channel (3) to eliminate the in-plane residual stress of the aluminum plate (12). In step S3, the controller employs stress-strain dual closed-loop feedback control, using a tension sensor to monitor the axial tensile force F borne by the aluminum plate (12) in real time. 拉 And combined with the roller axis speed V fed back by the encoder 辊轴 and traction line speed V 牵引 The output of the hydraulic drive mechanism is adjusted in real time to keep the actual elongation of the aluminum plate within the preset target plastic elongation range. At the same time, the controller will compare the real-time monitored tensile force F with the preset safety tensile force threshold F. Safety Compare, if F 拉 Reaching or exceeding F Safety The controller then forcibly adjusts the hydraulic drive mechanism to reduce or eliminate the speed difference, preventing the aluminum plate from breaking. In S2 and S3, the controller continuously receives the detection results of the thermocouple (8d) on the surface of the roller (6), and the controller corrects the flow output of each independent circulation unit (8) in the refrigerant circulation system in real time according to the detection results in order to maintain the stability of the roller gap of the S-shaped shaping channel (3).

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