Roll forming machine and roll forming method

Abstract

To provide a roll former which can accurately perform bending processing of a metallic material subjected to solution treatment.SOLUTION: A roll former comprises: fulcrum roll parts 21, 22; a bending roll part 23; an actuator 24 or 26; and a control device 41. The fulcrum roll parts 21, 22 have fulcrum rolls 21a, 21b, 22a, 22b contacting a long material 100. The bending roll part 23 has bending rolls 23a, 23b which bend the long material 100 by contacting the long material 100. The actuator 24 or 26 generates power. The control device 41 controls the actuator 24 or 26 on the basis of an exposure temperature or exposure time of the long material 100 after the solution treatment to change positions of the fulcrum rolls 21a, 21b, 22a, 22b or the bending rolls 23a, 23b.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] This application mainly relates to a roll forming machine that performs bending on a long workpiece to manufacture roll formed parts.

Background Art

[0002] Patent Document 1 discloses a hot bending processing device for performing hot bending on a metal material. The hot bending processing device includes a feeding means for feeding out the metal material, a heating means for locally heating the metal material, a cooling means for cooling the heated portion, and a clamping means for applying a bending moment to the heated portion. The hot bending processing device measures the displacement or temperature of the metal material to obtain a measurement value. The hot bending processing device controls the feeding means and the clamping means based on the measurement value. As a result, deformation and seizure due to residual stress are unlikely to occur, enabling high-precision hot bending processing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When manufacturing metal parts by processing a metal material, the metal material may be subjected to a solution treatment. The solution treatment is a process of heating the metal material at a high temperature to uniformly dissolve the additive elements into the metal material and then rapidly cooling the metal material. Subsequently, the material strength of the metal material increases due to age hardening. Here, the processing device of Patent Document 1 targets hot bending. Therefore, Patent Document 1 does not disclose means for improving processing accuracy in the bending of a solution-treated metal material.

[0005] This application has been made in view of the above circumstances, and its main purpose is to provide a roll forming machine that can accurately bend solution-treated metal materials. [Means for solving the problem]

[0006] The problem that this application aims to solve is as described above, and next, the means for solving this problem and their effects will be explained.

[0007] From the perspective of this application, a roll forming machine having the following configuration is provided. That is, the roll forming machine manufactures roll-formed parts by bending a solution-treated long material while conveying it along a conveying path. The roll forming machine comprises a pivot roll section, a bending roll section, an actuator, and a control device. The pivot roll section is arranged along the conveying path and has a pivot roll that contacts the long material. The bending roll section is arranged along the conveying path downstream of the pivot roll section and has a bending roll that contacts the long material and bends it. The actuator generates power to change the position of the pivot roll or the bending roll. The control device controls the actuator based on the exposure temperature and exposure time of the solution-treated long material to change the position of the pivot roll or the bending roll. [Effects of the Invention]

[0008] According to this application, it is possible to perform bending of solution-treated metal materials with high precision. [Brief explanation of the drawing]

[0009] [Figure 1] Schematic plan view of a roll forming machine. [Figure 2] A cross-sectional view showing how a long material is clamped in the first support roll section. [Figure 3] Plan view and block diagram of a bending machine. [Figure 4] A cross-sectional view showing the gap between the rolls in the first support roll section. [Figure 5]A plan view showing how the radius of curvature of a long material changes when the position of the bending roll section is changed. [Figure 6] A flowchart illustrating the process of changing the position of each roll in a bending machine based on exposure temperature and exposure time. [Figure 7] A graph showing the relationship between exposure temperature, exposure time, and material strength. [Figure 8] A graph showing the relationship between material strength, radius of curvature of roll-formed parts, and the position of the bending roll section. [Figure 9] A diagram explaining flatness (amount of floating). [Figure 10] A graph showing the relationship between flatness (amount of floating), material strength, thickness of long material, and gap between rolls. [Figure 11] A plan view showing a modified example in which the bending roll section is composed of three bending rolls. [Modes for carrying out the invention]

[0010] Next, embodiments of this application will be described with reference to the drawings. First, an overview of the roll forming machine 1 will be described with reference to Figure 1.

[0011] The roll forming machine 1 processes the long material 100 while transporting it along the transport path 10 to manufacture roll-formed parts 101. Multiple rolls are provided along the transport path 10, and the long material 100 is transported by these rolls gripping and feeding it out. As shown in Figure 1, the long material 100 is set at the uppermost part of the transport path 10, for example, in a rolled state, but the long material 100 is not limited to a rolled state and may be pre-cut to the required length. The roll forming machine 1 includes, in order from the upstream side of the transport path 10, a cross-section processing machine 11, a bending machine 12, a cutting machine 13, and a support stand 14.

[0012] The long material 100 is a material in which the size in one direction is larger than the size in other directions. In this embodiment, the long material 100 is plate-shaped, and its size in the longitudinal direction is significantly larger than its size in the thickness and width directions. Hereinafter, the shape of the long material 100 in a cross-section cut with a plane perpendicular to the longitudinal direction of the long material 100 will simply be referred to as the cross-section. The cross-section of the long material 100 before processing is rectangular, but it may be circular or have a different shape. The long material 100 is made of metal, for example, a 7000 series aluminum alloy. However, the long material 100 is not limited to a 7000 series aluminum alloy, but may be made of other aluminum alloys such as the 2000 series or other metals.

[0013] The cross-section processing machine 11 changes the cross-sectional shape of the long material 100. Specifically, the cross-section processing machine 11 is equipped with processing rolls 11a and 11b. There may be multiple processing rolls 11a and 11b. The rotation axes of the processing rolls 11a and 11b are, for example, parallel to the width direction of the long material 100. The rotation axes of the processing rolls 11a and 11b may be at an angle to the width direction of the long material 100. The surface of the processing roll 11a has a recess or a protrusion, and the surface of the processing roll 11b has a protrusion or recess that is opposite in shape to the recess or protrusion of the processing roll 11a. By gripping the long material 100 between the processing rolls 11a and 11b and feeding it, the cross-sectional shape of the long material 100 is changed. Note that the cross-section processing machine 11 is not an essential component. The cross-sectional shape of the long material 100 may be changed at another location using processing rolls 11a and 11b, or after changing the cross-sectional shape of the long material 100 by a known method that does not use rolls, the long material 100 may be moved to the location where the bending machine 12 is installed. If processing of the cross-sectional shape is not required, the cross-sectional processing machine 11 may be omitted.

[0014] The bending machine 12 changes the shape in the longitudinal direction of the long member 100, that is, the curvature. Before processing, the longitudinal direction of the long member 100 is linear, but due to the bending process of the bending machine 12, the longitudinal direction of the long member 100 becomes curved, that is, arc-shaped. The bending machine 12 includes a first fulcrum roll section 21, a second fulcrum roll section 22, and a bending roll section 23 in order from the upstream side of the conveyance path 10. Note that there may be three or more fulcrum roll sections, or there may be two or more bending roll sections. It is desirable that the rotation axes of these rolls be parallel to the thickness direction of the long member 100 before the cross-sectional shape changes. However, the rotation axes of the rolls do not necessarily have to be parallel to the thickness direction of the long member 100. In FIG. 2, the first fulcrum roll section 21 is shown. The first fulcrum roll section 21 includes first fulcrum rolls 21a and 21b. It is desirable that the outer surfaces of the first fulcrum rolls 21a and 21b have a shape along the cross-section of the long member 100. However, for example, in a portion where the cross-section of the long member 100 is curved, it is not necessarily required that the outer surfaces of the fulcrum rolls 21a and 21b have a shape along the long member 100. Note that the shapes of the second fulcrum roll section 22 and the bending roll section 23 are the same as those of the first fulcrum roll section 21. The detailed configuration of the bending machine 12 will be described later.

[0015] The cutting machine 13 includes a cutter or the like and cuts the long member 100. By cutting the long member 100 that has been processed by the cross-section processing machine 11 and the bending machine 12 with the cutting machine 13, the roll-formed part 101 is manufactured. The manufactured roll-formed part 101 is placed on the receiving base 14. Note that the cutting machine 13 is not an essential component. For example, when manufacturing one roll-formed part 101 by processing one long member 100, or when forming a material that has been cut to the required length in advance, the cutting machine 13 can be omitted.

[0016] The receiving base 14 is a base for placing the manufactured roll-formed part 101. The receiving base 14 preferably has a shape along the shape of the roll-formed part 101, but may also have a shape that can place the roll-formed part 101 even if it does not follow the shape of the roll-formed part 101. A plurality of distance sensors for checking the shape, i.e., the curvature, of the manufactured roll-formed part 101, or a plurality of rod-shaped indexes, may be arranged on the receiving base 14 at predetermined intervals. Further, a measuring device for measuring the flatness of a predetermined representative surface of the manufactured roll-formed part 101 may be provided.

[0017] Next, referring to FIGS. 3 to 5, the details of the bending machine 12 will be described. In the following description, the shape of the rolls constituting the bending machine 12 may be illustrated in a simplified manner.

[0018] The bending machine 12 includes a fulcrum base 31 and a bending base 32. The above-described first fulcrum roll part 21 and second fulcrum roll part 22 are attached to the fulcrum base 31. The above-described bending roll part 23 is attached to the bending base 32. The first fulcrum roll part 21 and the second fulcrum roll part 22 are arranged along a certain straight line. The bending roll part 23 is arranged at a position deviated from this straight line. Thereby, the long member 100 can be bent.

[0019] As described above, the first fulcrum roll part 21 includes a pair of first fulcrum rolls 21a and 21b. The first fulcrum rolls 21a and 21b are arranged to face each other with the long member 100 sandwiched in the thickness direction. At least one of the first fulcrum rolls 21a and 21b is rotationally driven by an actuator. The actuator is, for example, an electric motor. By the first fulcrum rolls 21a and 21b contacting and rotating the long member 100, the long member 100 can be conveyed.

[0020] Furthermore, the first pivot roll section 21 has a mechanism for changing the gap between the first pivot rolls 21a and 21b. Specifically, the first pivot roll 21a is configured to slide in a direction toward and toward the first pivot roll 21b. In the plan view of Figure 3, the sliding direction is the direction that connects the rotation centers of the first pivot rolls 21a and 21b.

[0021] In detail, a slide shaft 21c is attached to the first pivot roll 21a, and an actuator 24 is attached to the slide shaft 21c. The actuator 24 is a cylinder or solenoid that generates power to slide the first pivot roll 21a via the slide shaft 21c. The actuator 24 may also be an electric motor or a ball screw. By driving the actuator 24, the first pivot roll 21a can be moved toward or away from the first pivot roll 21b via the slide shaft 21c. As a result, the gap between the first pivot rolls 21a and 21b can be changed.

[0022] Figure 4 shows a diagram illustrating the change in the gap between the first support rolls 21a and 21b. In this embodiment, a reference plane is defined for the position of the first support roll 21a. The reference plane in this embodiment is parallel to the axis of rotation. The size of the gap is determined by defining the direction that moves the first support roll 21a away from the first support roll 21b as negative, using the reference plane as a reference. Conversely, the size of the gap is determined by defining the direction that moves the first support roll 21a closer to the first support roll 21b as positive, using the reference plane as a reference. The position of the reference plane is predetermined, and the state of the actuator 24 when the first support roll 21a coincides with the reference plane is stored. Furthermore, by specifying the gap, the actuator 24 can be driven to achieve that gap.

[0023] Note that the configuration for changing the gap between the first support rolls 21a and 21b may differ from that of this embodiment. For example, the first support roll 21b may be slid in place of or in addition to the first support roll 21a. In this case, the reference plane may be the position of the first support roll 21b.

[0024] The second pivot roll section 22, like the first pivot roll section 21, comprises a pair of second pivot rolls 22a and 22b and a slide shaft 22c. In the second pivot roll section 22, the gap between the second pivot rolls 22a and 22b can be changed by sliding at least one of the second pivot rolls 22a and 22b.

[0025] The bending roll section 23, like the first pivot roll section 21, comprises a pair of bending rolls 23a and 23b and a slide shaft 23c. In the bending roll section 23, the gap between the bending rolls 23a and 23b can be changed by sliding at least one of the bending rolls 23a and 23b.

[0026] Furthermore, the bending roll section 23 has a pivot mechanism and a sliding mechanism that change its relative position to the second pivot roll section 22. The pivot mechanism includes a pivot axis 23d. The bending roll section 23 is mounted on the bending base 32 so as to be rotatable about the pivot axis 23d. Actuators 25 and 26 are further attached to the bending roll section 23. By driving actuator 25, the bending roll section 23 can be rotated about the pivot axis 23d. The sliding mechanism is a mechanism for sliding the bending roll section 23. In the plan view of Figure 3, the sliding direction is the direction that connects the rotation centers of the bending rolls 23a and 23b. By driving actuator 26, the bending rolls 23a, 23b and the pivot axis 23d can be slid integrally. Actuator 25 is, for example, an electric motor. Actuator 26 is a cylinder or a solenoid. Actuator 26 may be an electric motor and a ball screw.

[0027] By having a swivel mechanism and a sliding mechanism, the relative position of the bending roll section 23 with respect to the second pivot roll section 22 can be changed. This allows the degree of bending of the long material 100, or in other words, the radius of curvature of the long material 100, to be changed, as shown by the dashed line in Figure 5. Note that the mechanism for changing the relative position of the bending roll section 23 with respect to the second pivot roll section 22 may differ from that of this embodiment. For example, the bending base 32 may be able to move freely in a horizontal plane.

[0028] The actuators 24, 25, and 26 described above are controlled by the control device 41. The control device 41 comprises an arithmetic unit such as a CPU, a storage device such as an SSD or flash memory, and a communication device such as a communication module. By executing a program stored in the storage device, the arithmetic unit can perform various controls on the bending machine 12. In addition, the control device 41 can acquire various data by accessing the database device 43 using the communication device. The control device may also include a clock or time measuring device inside.

[0029] The database device 43 can communicate with the control device 41 via a local area network or a wide area network. The database device 43 is a server equipped with a storage device such as an HDD or SSD. The database device 43 stores the data necessary for controlling the roll forming machine 1 and transmits this data in response to requests from the control device 41. Note that the data necessary for controlling the roll forming machine 1 may be stored in the control device 41 instead of the database device 43. In this case, the database device 43 can be omitted.

[0030] Furthermore, a temperature sensor 42 is provided in the environment where the roll forming machine 1 is installed. The temperature sensor 42 measures the exposure temperature, which is the temperature of the environment to which the long material 100 is exposed. The temperature sensor 42 outputs the measured exposure temperature to the control device 41. Alternatively, the exposure temperature measured by the temperature sensor 42 may be output directly to the database device 43 and stored therein, instead of being output to the control device 41.

[0031] Furthermore, a clock or stopwatch is installed in the environment where the long material 100 is solution-treated, transported, or stored before being supplied to the bending machine 12. The clock or stopwatch measures the total exposure time, which is the sum of the time the long material 100 is exposed to the ambient temperature environment after the solution-treated treatment. The total exposure time of the long material 100 is recorded automatically or manually using an input device. For example, a stopwatch may be installed on the long material 100, and the stopwatch may start measuring time when exposure to ambient temperature begins. The stopwatch may be stopped when the long material 100 is moved to a freezer, and the stopwatch may be restarted when it is moved from the freezer to the ambient temperature environment, thereby measuring the total exposure time of the long material 100. The time when the exposure of the long material 100 began, or the total exposure time of the long material 100, is output to the control device 41, or input to the control device 41 by an input device. The time at which exposure begins to start time measurement with a stopwatch may be the time when the long material 100 reaches a predetermined temperature. Furthermore, the clock or stopwatch may be placed in a different location from the long material 100.

[0032] Next, referring to Figures 6 to 10, the process of changing the position of each roll in the bending machine 12 based on the exposure temperature and exposure time will be described.

[0033] First, the characteristics of the long material 100 will be described. The long material 100 in this embodiment has been solution-treated. Solution treatment is a process in which a metal material is heated to a high temperature to uniformly dissolve additive elements into the metal material, and then the metal material is rapidly cooled. As a result, age hardening occurs in the long material 100 after solution treatment, and the material strength of the long material 100 increases. The tempered state of the metal after solution treatment and until age hardening is completed is sometimes referred to as W. The processing of the long material 100 by the roll forming machine 1 is performed in the tempered state W of the long material 100. Therefore, if the exposure conditions up to the start of processing are unknown, the accurate material strength of the long material 100 at the time of processing is unknown.

[0034] Furthermore, if the material strength of the long material 100 differs at the time of processing, the shape of the roll-formed part 101 produced may differ even if the long material 100 is processed under the same processing conditions, such as the roll position. For example, the higher the material strength of the long material 100, the greater the springback after bending by the bending machine 12, resulting in a larger radius of curvature of the roll-formed part 101. Also, the lower the material strength of the long material 100, the more likely the flatness of the roll-formed part 101 is to be poor. Thus, if the material strength of the long material 100 at the time of processing is unknown, it may not be possible to obtain the desired shape, potentially leading to a decrease in yield. In this embodiment, to resolve this, the first and second corrections shown in the flowchart of Figure 6 are performed. The first correction is a process to adjust the radius of curvature of the roll-formed part 101 appropriately, and the second correction is a process to adjust the flatness of the roll-formed part 101 appropriately. These will be explained in detail below.

[0035] First, the control device 41 determines whether or not it is the first correction timing (S101). In this embodiment, a roll forming machine 1 processes a long material 100 to manufacture multiple roll forming parts 101. The first correction timing is, for example, the timing to start manufacturing a new roll forming part 101. This allows each roll forming part 101 to be processed under appropriate conditions. Note that the first correction timing may be a different timing from that in this embodiment. For example, the first correction timing may be the elapsed time. In this case, the first correction timing may occur in the middle of manufacturing one roll forming part 101.

[0036] If the control device 41 determines that it is the first correction timing, it acquires the exposure temperature and exposure time at the time it was determined to be the first correction timing (S102). The control device 41 continuously acquires the temperature detected by the temperature sensor 42 and stores it in the memory. The arithmetic unit of the control device 41 acquires this exposure temperature by accessing the memory. The exposure time is the length of time the material is exposed to an environment such as room temperature after the solution treatment. The control device 41 stores in the memory the total exposure time of the long material 100 up to the time when exposure of the long material 100 in use began or when molding in the roll forming machine 1 began. The total exposure time of the long material 100 up to the time when exposure of the long material 100 began or when molding in the roll forming machine 1 began may be automatically recorded in the memory by some sensor that monitors the long material 100, or it may be manually entered and stored in the memory using an input device. The arithmetic unit of the control device 41 calculates the exposure time based on the time obtained by accessing the storage device and the time at which it is determined to be the first correction timing, or the total exposure time obtained by accessing the storage device and the time at which it is determined to be the first correction timing. The time at which it is determined to be the first correction timing may be obtained from a clock built into the control device 41, or the time from a clock outside the control device 41 may be obtained using a sensor such as a camera, or it may be entered by a person using an input device.

[0037] Next, the control device 41 estimates the material strength based on the exposure temperature and exposure time (S103). The material strength of the long material 100 in tempered state W depends on the exposure temperature and exposure time, as shown in Figure 7. Figure 7 shows a graph illustrating the relationship between exposure temperature, exposure time, and material strength. The horizontal axis represents exposure time, and the vertical axis represents material strength. The material strength is, for example, the 0.2% yield strength or tensile strength of the material. The graph shown in Figure 7 was created based on data previously obtained experimentally. This data or graph is stored in the database device 43. The control device 41 retrieves this data or graph by accessing the database device 43.

[0038] As shown in the graph in Figure 7, the increase in material strength per unit of exposure time increases as the exposure temperature rises, and the material strength increases as the exposure time increases. However, as shown in Figure 7, the increase in material strength due to age hardening asymptotically approaches the material's inherent value, so the increase in material strength per unit of exposure time does not necessarily correspond to the magnitude of the exposure temperature. As shown in Figure 7, when the exposure temperature is Y°C and the exposure time is T1, the material strength can be estimated by referring to the material strength at exposure time T1 on the graph for exposure temperature Y°C. If the acquired exposure temperature is, for example, between X°C and Y°C, the material strength corresponding to the acquired exposure temperature can be determined by interpolating the graph for exposure temperature X°C and the graph for exposure temperature Y°C.

[0039] In this embodiment, the temperature sensor 42 detects the exposure temperature itself, but it may also detect a temperature linked to the exposure temperature. For example, the temperature sensor 42 may detect the temperature of the lubricating oil used in processing the long material 100, or the temperature of the long material 100 itself. Essentially, the material strength of a tempered material W exposed to an environment such as room temperature depends on the temperature and exposure time of the long material 100 itself. The temperature of the long material 100 itself depends, for example, on the temperature of the lubricating oil used in processing the long material 100, or on the exposure temperature. Therefore, even if the temperature sensor 42 detects a temperature other than that of the long material 100 and uses that temperature to estimate the material strength, it is essentially or substantially estimating the material strength based on the temperature of the long material 100 itself.

[0040] Next, the control device 41 determines the target position of the bending roll section 23 based on the target value of the radius of curvature of the roll-formed part 101 and the material strength of the long material 100 (S104). As described above, the radius of curvature of the roll-formed part 101 depends on the material strength. Also, as explained using Figure 5, the radius of curvature of the roll-formed part 101 naturally depends on the position of the bending roll section 23. Furthermore, since springback depends on the cross-sectional shape of the long material 100, the radius of curvature of the roll-formed part 101 depends on the cross-sectional shape of the long material 100. Figure 8 shows a graph showing the relationship between material strength, the position of the bending roll section 23, and the radius of curvature of the roll-formed part 101, taking the case where the cross-sectional shape of the long material 100 is the same except for the thickness as an example, and the thickness is D1 mm. The horizontal axis is material strength, and the vertical axis is the radius of curvature of the roll-formed part 101. The graph shown in Figure 8 was created based on data obtained experimentally in advance. This data or graph is stored in the database device 43. The control device 41 retrieves this data or graph by accessing the database device 43. Note that the database device 43 also stores data or graphs with thicknesses other than D1mm.

[0041] As shown in Figure 8, if the thickness of the long material 100 is D1 mm, the target value of the radius of curvature of the roll-formed part 101 is R1, and the material strength estimated in step S103 is S1, then the graph for position B exists at this intersection. In this case, the control device 41 identifies position B as the target position of the bending roll section 23. If this intersection is, for example, between position A and position B, the position of the bending roll section 23 is determined by interpolating the graphs of position A and position B.

[0042] If the long material 100 has only one thickness, or if there are multiple thicknesses but the differences are slight, the position of the bending roll section 23 may be determined using the same data regardless of the thickness of the long material 100. In this embodiment, the positions of the first support roll section 21 and the second support roll section 22 are fixed, and only the position of the bending roll section 23 is changed. On the other hand, since the relative position of the bending roll section 23 with respect to the second support roll section 22 depends on the radius of curvature of the roll-formed part 101, the position of the second support roll section 22 may be changed in place of or in addition to the bending roll section 23. Alternatively, instead of estimating the position of the bending roll section 23 based on a graph, a relational expression showing the relationship between the radius of curvature, the position of the bending roll section 23, and the material strength may be created, and the position of the bending roll section 23 may be determined based on this relational expression.

[0043] In step S104, the control device 41 may calculate a target rotation angle of the bending roll section 23 centered on the rotation axis 23d based on the identified target position of the bending roll section 23 and the target value of the radius of curvature of the roll forming part 101.

[0044] Next, the control device 41 generates a drive command to move the bending roll section 23 to the target position and controls the actuator 26 (S105). The drive command is a command necessary to move the bending roll section 23 from its current position to the target position. If the target rotation angle of the bending roll section 23 was calculated in step S104, a drive command to rotate the bending roll section 23 may also be generated at the same time to control the actuator 25.

[0045] Next, the control device 41 determines whether or not it is the second correction timing (S106). The timings that can be set as the second correction timing are the same as those for the first correction timing. Also, the first correction timing and the second correction timing may be the same or different.

[0046] If the control device 41 determines that it is the second correction timing, it acquires the exposure temperature and exposure time (S107) and estimates the material strength based on the exposure temperature and exposure time (S108). The process in step S107 is the same as the process in step S102, and the process in step S108 is the same as the process in step S103. If the second correction timing is the same as the first correction timing, the exposure temperature and exposure time acquired in step S102 may be used in step S107, or the material strength estimated in step S103 may be used in step S108.

[0047] Next, the control device 41 determines the gap between the rolls based on the target value of the flatness of the roll-formed part 101, the material strength of the long material 100, and the thickness of the long material 100 (S109). Flatness is an index that indicates the magnitude of the error from a reference plane. For example, if the flatness is 1 mm, the plane of interest will be located between two virtual planes arranged parallel to each other at a 1 mm interval. As shown in Figure 9, the completed roll-formed part 101 is placed on the mounting surface of the support base 14. Here, if the flatness of the representative surface of the roll-formed part 101, which will be described later, is large, a part of the roll-formed part 101 will lift up from the mounting surface of the support base 14. Therefore, flatness and the amount of lift are indices of the same concept. In the following, the term flatness will be used as a representative term. The representative surface is a surface that the roll-formed part 101 has, and is a surface that is predetermined according to the shape of the roll-formed part 101. In this embodiment, the representative surface is the surface of the portion of the roll-formed part 101 that has the longest length when viewed in a direction perpendicular to the transport path 10, and is a plane perpendicular to the thickness direction of that portion. Figure 9 corresponds to a view of the roll-formed part 101 in a direction perpendicular to the transport path 10. In Figure 9, the upper surface of the roll-formed part 101 is shown as the representative surface, but the lower surface may also be treated as the representative surface. Note that the representative surface in this embodiment is just one example, and a different surface of the roll-formed part 101 may be treated as the representative surface.

[0048] Figure 10 shows, from top to bottom, graphs showing the relationship between flatness and material strength, the relationship between flatness and the thickness of the long material 100, and the relationship between flatness and the gap between the rolls. In the upper graph of Figure 10, the horizontal axis is material strength and the vertical axis is flatness. In the middle graph of Figure 10, the horizontal axis is the thickness of the long material 100 and the vertical axis is flatness. In the lower graph of Figure 10, the horizontal axis is the gap between the rolls and the vertical axis is flatness. The graphs shown in Figure 10 were created based on data obtained experimentally in advance. As shown in each graph of Figure 10, flatness depends on the material strength, the thickness of the long material 100, and the gap between the rolls. Therefore, the following equation (1) holds true. Flatness = (a1 * material strength) + (a2 * thickness) + (a3 * gap between rolls) + b ... (1) Equation (1) is the regression equation obtained by multiple regression analysis. a1, a2, and a3 are the partial regression coefficients. b is the intercept, or in other words, the constant term. By substituting the data used to create the graph in Figure 10 into equation (1), the values ​​of a1, a2, a3, and b can be estimated. Furthermore, by rearranging equation (1), the following equation (2) can be obtained. Gap between rolls = (flatness - a1 · material strength - a2 · thickness - b) / a3 ... (2) However, the equation that gives the gap between the rolls as the solution does not necessarily have to be equation (2) obtained by rearranging equation (1). The coefficients and constant term may be determined experimentally. This will yield equation (3) below. Gap between rolls = (c1·flatness) + (c2·material strength) + (c3·thickness) + d···(3) c1, c2, and c3 are coefficients, and d is the constant term.

[0049] The control device 41 determines the target value of flatness and step S10 8The gap between the rolls is determined by substituting the estimated material strength and thickness into equation (2) or equation (3). If the long material 100 has only one thickness, or if there are multiple thicknesses but the differences are small, the term relating to the thickness of the long material 100 may be omitted. Alternatively, instead of using a relational equation to determine the gap between the rolls, the gap between the rolls may be determined from the position of the bending roll section 23 in the first correction, i.e., from the positional relationship shown on the graph.

[0050] Next, the control device 41 generates a drive command to control the actuator 24 so that the gaps between the rolls of the first pivot roll section 21, the second pivot roll section 22, and the bending roll section 23 become the specified gaps (S110).

[0051] Next, the control device 41 determines whether the termination conditions have been met (S111). The termination conditions are conditions for determining whether the manufacturing process of the roll-formed parts 101 has been completed. The termination conditions are, for example, that the manufacturing of a specified number of roll-formed parts 101 has been completed, or that the termination time has been reached. If the control device 41 determines that the termination conditions have been met, it terminates the control. If the control device 41 determines that the termination conditions have not been met, it returns to the process of step S101.

[0052] By performing the above processing, even when the long material 100 is in a tempered state W and the exact material strength of the long material 100 at the time of processing is unknown, the material strength can be estimated and processing conditions can be set accordingly, thereby increasing the accuracy of the shape of the roll-formed part 101.

[0053] As described above, the roll forming machine 1 of this embodiment has the following feature 1 and performs the following roll forming method. That is, the roll forming machine 1 manufactures roll formed parts 101 by bending a solution-treated long material 100 while conveying it along a conveying path 10. The roll forming machine 1 comprises pivot roll sections 21, 22, a bending roll section 23, an actuator 24 or 26, and a control device 41. The pivot roll sections 21, 22 are arranged along the conveying path 10 and are in contact with the long material 100. The bending roll section 23 is arranged along the conveying path 10 downstream of the pivot roll sections 21, 22 and is in contact with the long material 100 to bend it. The actuators 24 and 26 generate power to change the position of the pivot rolls 21a, 21b, 22a, 22b or the bending rolls 23a, 23b. The control device 41 controls the actuator 24 based on the exposure temperature and exposure time of the long material 100 after solution treatment to change the position of the pivot rolls 21a, 21b, 22a, 22b or the bending rolls 23a, 23b. This is Feature 1.

[0054] This allows the actuator 24 to be controlled based on the exposure temperature and exposure time, thereby controlling each roll while taking into account the current material strength of the long material 100. As a result, the solution-treated long material 100 can be bent with high precision.

[0055] The roll forming machine 1 of this embodiment has the following feature 2. Specifically, in the roll forming machine 1, the control device 41 controls the actuator 26 based on the exposure temperature and exposure time, and the target value of the radius of curvature of the roll forming part 101, thereby changing the relative position of the bending roll section 23 with respect to the pivot roll sections 21 and 22. This is feature 2.

[0056] This allows the radius of curvature of the roll-formed part 101 to be brought closer to the target value with high precision.

[0057] The roll forming machine 1 of this embodiment has the following feature 3. That is, in the roll forming machine 1, the pivot roll sections 21 and 22 have a pair of pivot rolls 21a and 21b that grip the long material 100, or the bending roll section 23 has a pair of bending rolls 23a and 23b that grip the long material 100. The control device 41 controls the actuator 24 to change the gap between the pivot rolls 21a and 21b, or the gap between the bending rolls 23a and 23b. The above is feature 3.

[0058] The roll forming machine 1 of this embodiment has the following feature 4. Specifically, the control device 41 estimates the material strength of the long material 100 based on the exposure temperature and exposure time, and controls the actuator 24 or 26 based on the material strength. This concludes feature 4.

[0059] This allows for the estimation of material strength using a simple method.

[0060] The roll forming machine 1 of this embodiment has the following feature 5. Specifically, the control device 41 accesses a database that associates exposure temperature, exposure time, and material strength, identifies the material strength corresponding to the exposure temperature and exposure time of the long material 100 after solution treatment, and estimates the material strength. This is feature 5.

[0061] This allows for accurate estimation of material strength by using a database.

[0062] The roll forming machine 1 of this embodiment has the following feature 6. That is, each time the production of a new roll forming part 101 is started, the control device 41 controls the actuator 24 or 26 to change the position of the pivot rolls 21a, 21b, 22a, 22b or the bending rolls 23a, 23b. This is feature 6.

[0063] This allows the production of the roll-formed part 101 to begin under appropriate processing conditions. Furthermore, by not changing the processing conditions during the production of the roll-formed part 101, it is possible to make, for example, the curvature or flatness of the roll-formed part 101 uniform.

[0064] The roll forming machine 1 of this embodiment has the following feature 7. That is, the control device 41 controls the actuator 24 or 26 to change the position of the pivot rolls 21a, 21b, 22a, 22b or the bending rolls 23a, 23b during the process of bending a long material 100 to manufacture one roll forming part 101. The above is feature 7.

[0065] This makes it possible to manufacture, for example, roll-formed parts 101, which take a long time to manufacture, with high precision.

[0066] The roll forming machine 1 of this embodiment has the following feature 8. That is, the bending roll section 23 has two or more bending rolls 23a, 23b that sandwich the long material 100. The bending roll section 23 rotates around a pivot axis 23d that is parallel to the rotation axes of the bending rolls 23a, 23b. For example, the control device 41 controls, for example, the actuator 26 to change the relative position of the bending roll section 23 with respect to the pivot roll section 21, and controls the actuator 25 to rotate the bending roll section 23. The above is feature 8.

[0067] This simplifies the mechanism for changing relative positions.

[0068] The roll forming machine 1 of this embodiment has the following feature 9. Specifically, the control device 41 further controls the actuator 26 based on the thickness of the long material 100. These are the features 9.

[0069] This allows for even more precise molding of the radius of curvature of the roll-formed part 101.

[0070] The roll forming machine 1 of this embodiment has the following features 10. Specifically, the control device 41 accesses a database that associates material strength, the radius of curvature of the roll forming part 101, and the relative position, identifies the relative position corresponding to the estimated target values ​​of material strength and the radius of curvature of the roll forming part 101, and controls the actuator 26 based on the identified relative position. These are the features 10.

[0071] This allows for more precise molding of the radius of curvature of the roll-formed part 101 by using values ​​from the database.

[0072] The roll forming machine 1 of this embodiment has the following features 11. Specifically, the control device 41 estimates the material strength of the long material 100 based on the exposure temperature and exposure time. The control device 41 controls the actuator 24 based on the material strength and a predetermined target value for the flatness of a representative surface of the roll forming part 101. These are the features 11.

[0073] This makes it possible to bring the flatness of the representative surface of the roll-formed part 101 closer to the target value.

[0074] The roll forming machine 1 of this embodiment has the following features 12. Specifically, the control device 41 controls the actuator 24 based on the material strength, a predetermined target value for the flatness of a representative surface of the roll forming part 101, and the thickness of the long material 100. These are the features 12.

[0075] As a result, by using the thickness of the long material 100, the flatness of the roll-formed part 101 can be formed with even greater precision.

[0076] The roll forming machine 1 of this embodiment has the following features 13. Specifically, the control device 41 identifies the gap using estimated target values ​​for material strength and flatness as input values, based on a relational expression showing the relationship between material strength, the flatness of a predetermined representative surface of the roll forming part 101, and the gap between the rolls, and controls the actuator 24 based on that gap. These are the features 13.

[0077] This allows for the identification of gaps between rolls with a simple process.

[0078] In the roll forming machine 1 of this embodiment, the representative surface is the surface of the portion of the roll forming part 101 that has the longest length when viewed in a direction perpendicular to the transport path 10, and is a plane perpendicular to the thickness direction of that portion. The control device 41 controls the actuator 24 based on the material strength and the target value of the flatness of the representative surface. These are the features 14.

[0079] This allows the actuator 24 to be controlled using the surface that most significantly affects the lifting of the roll-formed part 101 as the representative surface. As a result, the lifting of the roll-formed part 101 can be kept within a desired range.

[0080] Features 1 through 14 described above can be combined as appropriate, as long as no contradictions arise. For example, feature 3 can be combined with at least one of features 1 or 2. Feature 4 can be combined with at least one of features 1 through 3. Feature 5 can be combined with at least one of features 1 through 4. Feature 6 can be combined with at least one of features 1 through 5. Feature 7 can be combined with at least one of features 1 through 6. Feature 8 can be combined with at least one of features 1 through 7. Feature 9 can be combined with at least one of features 1 through 8. Feature 10 can be combined with at least one of features 1 through 9. Feature 11 can be combined with at least one of features 1 through 10. Feature 12 can be combined with at least one of features 1 through 11. Feature 13 can be combined with at least one of features 1 through 12. Feature 14 can be combined with at least one of features 1 through 13.

[0081] Although preferred embodiments of this application have been described above, the above configuration can be modified as follows, for example.

[0082] The bending machine 12 in the above embodiment is just an example, and the number of each roll may differ from that in the above embodiment. The bending machine 12 only needs to be equipped with a first support roll 21b, a second support roll 22a, and a bending roll 23b, and other rolls may be omitted. In this case, since there will be no gap between the rolls, the processes from steps S106 to S110 in Figure 6 can be omitted.

[0083] Furthermore, the rolls constituting the first support roll section 21 are not limited to one or two, but may be three or more. Similarly, the rolls constituting the second support roll section 22 or the bending roll section 23 are not limited to one or two, but may be three or more. When there are two or more rolls constituting the first support roll section 21, etc., these rolls are arranged on both sides of the long material 100 in the thickness direction. In other words, these rolls are arranged to sandwich the long material 100. Also, when there are three or more rolls constituting the first support roll section 21 or the second support roll section 22, the processing from steps S106 to S110 in Figure 6 can be omitted. However, when the first support roll section 21 or the second support roll section 22 is composed of a pair of rolls, it is preferable to perform the processing from steps S106 to S110 in Figure 6, regardless of the number of rolls constituting the bending roll section 23.

[0084] Furthermore, as shown in Figure 11, the bending roll section 23 may be composed of three bending rolls 23a1, 23a2, and 23b. Two bending rolls 23a1 and 23a2 are positioned on one side in the thickness direction of the long material 100, and one bending roll 23b is positioned on the other side in the thickness direction of the long material 100. In this case, as shown below, the position of the bending roll section 23 can be appropriately adjusted even if the actuator 25 for rotating the bending roll section 23 is omitted. Specifically, the positional relationship of the three bending rolls 23a1, 23a2, and 23b is constant. Also, the bending rolls 23a1 and 23a2 are pivotably mounted to the bending roll 23b. When the long material 100 is supplied with the bending roll section 23 moved as shown by the dashed line in Figure 11, the long material 100 is deformed to come into contact with the three bending rolls 23a1, 23a2, and 23b. In other words, the bending roll section 23 rotates naturally without the need for actuator power, according to the curvature of the long material 100. Therefore, if there is an actuator to move the bending roll 23b, an actuator to rotate the bending roll section 23 is unnecessary. The position of the pivot axis of the bending roll section 23 is not particularly limited, but it is preferably the intersection point P1 of the perpendicular line L2 drawn from the midpoint of the line segment L1 connecting the centers of the bending rolls 23a1 and 23a2, and the center in the thickness direction of the long material 100. However, the position of the pivot axis of the bending roll section 23 may be at another position, for example, the center of the bending roll 23b.

[0085] In the above embodiment, the gap between the rolls is changed for all of the first support roll section 21, the second support roll section 22, and the bending roll section 23, but the process for one or two of the roll sections may be omitted. Furthermore, it is preferable to change the gap between the rolls at least for the second support roll section 22, which is considered to have the greatest impact on flatness.

[0086] The flowchart shown in the above embodiment is an example, and some processes may be omitted, some processes may be modified, or new processes may be added. For example, if the first correction timing and the second correction timing are the same, the processes from steps S106 to S109 can be omitted. Also, depending on the shape of the roll-formed part 101 or the required accuracy, either the first correction or the second correction may be omitted.

[0087] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor. [Explanation of Symbols]

[0088] 1. Roll forming machine 10. Transport Route 12 Bending machine 21. First support roll section 21a, 21b First pivot roll 22 Second pivot roll section 22a, 22b Second pivot roll 23 Bending Roll Section 23a, 23b Bending rolls 41 Control device 42 Temperature Sensor 100 long material 101 Roll-formed parts

Claims

1. In a roll forming machine that manufactures roll-formed parts by bending a long, solution-treated material while it is being transported along a transport path, A pivot roll section having pivot rolls arranged along the transport path and in contact with the long material, A bending roll section is arranged along the transport path downstream from the aforementioned pivot roll section and has a bending roll that contacts the long material and bends the long material, An actuator that generates power to change the position of the pivot roll or the bending roll, A control device that controls the actuator based on the exposure temperature and exposure time of the long material after solution treatment to change the position of the pivot roll or the bending roll, A roll forming machine equipped with the following features.

2. A roll forming machine according to claim 1, The control device controls the actuator based on the exposure temperature, the exposure time, and a target value for the radius of curvature of the roll-formed part, thereby changing the relative position of the bending roll portion with respect to the pivot roll portion.

3. A roll forming machine according to claim 1, The pivot roll section has a pair of pivot rolls that grip the long material, or the bending roll section has a pair of bending rolls that grip the long material. The control device controls the actuator to change the gap between the pivot rolls or the gap between the bending rolls in a roll forming machine.

4. A roll forming machine according to claim 1, The control device estimates the material strength of the long material based on the exposure temperature and the exposure time, and controls the actuator based on the material strength in a roll forming machine.

5. A roll forming machine according to claim 4, The control device is A roll forming machine that accesses a database that associates the exposure temperature, the exposure time, and the material strength, identifies the material strength corresponding to the exposure temperature and exposure time of the long material after solution treatment, and estimates the material strength.

6. A roll forming machine according to claim 1, The control device controls the actuator to change the position of the pivot roll or the bending roll each time the manufacture of a new roll-formed part is started in the roll-forming machine.

7. A roll forming machine according to claim 1, The control device controls the actuator to change the position of the pivot roll or the bending roll during the process of manufacturing one roll-formed part by bending a long material.

8. A roll forming machine according to claim 2, The bending roll section has two or more bending rolls that hold the long material, The bending roll section rotates around a pivot axis parallel to the rotation axis of the bending roll, The control device controls the actuator to change the relative position of the bending roll portion with respect to the pivot roll portion, and also rotates the bending roll portion in a roll forming machine.

9. A roll forming machine according to claim 2, The control device further controls the actuator based on the thickness of the long material in a roll forming machine.

10. A roll forming machine according to claim 2, The control device accesses a database that associates the material strength of the long material, the radius of curvature of the roll-formed part, and the relative position, identifies the relative position corresponding to the estimated target values ​​of the material strength and the radius of curvature of the roll-formed part, and controls the actuator based on the identified relative position.

11. A roll forming machine according to claim 3, The control device estimates the material strength of the long material based on the exposure temperature and the exposure time. The control device is a roll forming machine that controls the actuator based on the material strength and a predetermined target value for the flatness of a representative surface of the roll-formed part. A roll forming machine in which the flatness value of the representative surface is calculated by equation (1): flatness = (a1 material strength) + (a2 thickness) + (a3 gap between rolls) + b, where a1, a2, and a3 are coefficients and b is a constant term.

12. A roll forming machine according to claim 11, The control device controls the actuator of the roll forming machine based on the material strength, a predetermined target value for the flatness of a representative surface of the roll-formed part, and the thickness of the long material.

13. A roll forming machine according to claim 11, The control device is a roll forming machine that identifies the gap using estimated target values ​​of material strength and flatness as input values ​​for a relational expression showing the relationship between the material strength, the flatness of a predetermined representative surface of the roll-formed part, and the gap, and controls the actuator based on the identified gap. A roll forming machine in which the above relation is given by equation (2): gap between rolls = (flatness - a1 * material strength - a2 * thickness - b) / a3, or equation (3): gap between rolls = (c1 * flatness) + (c2 * material strength) + (c3 * thickness) + d, where a1, a2, and a3 in equation (2) are coefficients and b is a constant term, and c1, c2, and c3 in equation (3) are coefficients and d is a constant term.

14. A roll forming machine according to claim 11, The representative surface is the surface of the portion of the roll-formed part that has the longest length when viewed in a direction perpendicular to the transport path, and is a plane perpendicular to the thickness direction of that portion. The control device controls the actuator of a roll forming machine based on the material strength and a target value for the flatness of the representative surface.

15. In a roll forming method for manufacturing roll-formed parts, in which a solution-treated long material is conveyed along a transport path, and a pivot roll section having a pivot roll that contacts the long material, and a bending roll section having a bending roll that contacts the long material and bends the long material, A roll forming method that controls an actuator based on the exposure temperature and exposure time of the long material after solution treatment, thereby changing the position of the pivot roll or the bending roll.

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