JP4603193B2 - Body panel manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a vehicle body panel using plate materials having different thicknesses.
[0002]
[Prior art]
As a method of forming the differential thickness portion having different thicknesses, first, a method of forming the differential thickness portion on the plate material by rolling and then annealing the plate material formed with the differential thickness portion is known. Specifically, for example, rolling is disclosed in Japanese Patent Application Laid-Open No. 59-189004 “Differential Thick Plate Manufacturing Method and Rolling Machine”. According to FIG. 3 of the publication, the rolling mill for manufacturing the differential thickness plate independently uses the upper work roll 14a (the reference sign is the same as that described in the publication. The same applies hereinafter) and the lower work roll 14b. It can be driven and controlled, and the lower work roll 14b is driven in the reverse direction and rolled to form a differential thickness plate.
Next, the heating state of the plate after rolling will be described.
[0003]
FIGS. 15A and 15B are diagrams showing heating of a conventional plate material.
In (a), the plate member 141 is formed by forming the differential thickness portions 142 and 143, the differential thickness portion 142 has a thickness t2, and the differential thickness portion 143 has a thickness t3. t1 is the thickness of the plate 141, which is the thickness of the first plate.
The plate material 141 is put in the heating furnace 144 and heated by the heaters 145 (... indicates a plurality. The same applies hereinafter), and the plate material 141 is annealed. A, B, and C indicate measurement units that measure temperature. An example of the measurement results is shown in the following figure.
[0004]
(B) is a diagram showing the heating state of the plate material, where the horizontal axis is time, the vertical axis is the temperature of the plate material, and the heaters 145... Are controlled based on the temperature of the differential thickness portion 143 of the measurement unit C. The results are shown. The differential thickness portion 143 is raised to the temperature T1 at the temperature rise time m1, the output of the heater 145... Is lowered at the temperature T1, kept at the temperature T1 until the time m2, and the heater 145. . At that time, the measurement part A became temperature T3 and the measurement part B became temperature T2. Thus, by heating the board | plate material 141 with the heating furnace 144, the board | plate material 141 can be annealed and the board | plate material which shape | molded the difference thickness part can be obtained.
[0005]
[Problems to be solved by the invention]
The temperature of the plate 141 heated by using the heating furnace 144 is as shown in FIG. 15B, and the heating furnace 144 heats the difference thickness part 143 of the measurement part C to a desired temperature T1, but this is accompanied by this. In order to heat the difference thickness part 142 of the measurement part B to temperature T2, the dispersion | variation in the temperature of the board | plate material 141 at the time of annealing is large. Therefore, the plate material 141 has a difference in material strength between the strength of the material of the differential thickness portion 143 heat-treated at a desired temperature and the thickness of the differential thickness portion 142 heat-treated at a temperature other than that, In the heating furnace 144, it is difficult to make the material characteristics uniform.
[0006]
Moreover, since the temperature of the difference thickness part 142 of the measurement part B increases rapidly, distortion due to heating is likely to occur, and there is a concern that the plate material 141 may be distorted or wrinkled.
[0007]
Accordingly, an object of the present invention is to provide a method for manufacturing a vehicle body panel that can adjust a plate material formed with a differential thickness portion to a plate material that is annealed and has uniform material properties, and can prevent heating distortion. It is in.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, in claim 1, a plate material setting step of setting a plate material between upper and lower rolls of a rolling means, a gripping step of gripping both ends of the set plate material, and applying a constant tension to the gripped plate material A tension applying step, a difference thickness portion forming step in which a difference thickness portion is formed by rolling with upper and lower rolls while applying tension, and a formed plate material is continuously sent to a heating device provided in a conveyance line, after stopping at the position, and the annealing step of annealing in the range of each different thickness portion is moved a plurality of times different thickness portion of each linear heating means each corresponding to each different thickness portion at a predetermined heating conditions And a panel press forming step of forming the annealed plate material into a predetermined vehicle body panel with a press.
[0009]
The annealing step, after stopping the molded sheet at a predetermined position in the heating device, the difference in each plurality of times to move the range for each different thickness portion linear heating means each corresponding to each different thickness portion Since the thick part is annealed under a predetermined heating condition, it is possible to heat the inside of one differential thickness part by moving one linear heating means, and it is easy to control the temperature of each differential thickness part It is.
[0010]
Further, in the annealing step, after stopping the molded sheet at a predetermined position in the heating device, a plurality of times to move the range for each different thickness portion linear heating means each corresponding to each different thickness portion respectively Since the difference thickness part is annealed under a predetermined heating condition, a heating operation in which the temperature gradient of heating for each difference thickness part is relaxed is possible, and it is easy to carry out heating without causing distortion.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.
FIG. 1 is a plan view of a plate material manufacturing apparatus used in a vehicle body panel manufacturing method according to the present invention. In the upper left of the figure, Y is an axis indicating the rolling direction, indicating movement in the horizontal direction in the figure, and X is an axis orthogonal to Y.
The plate material manufacturing apparatus 10 includes a cutting machine 11, a rolling device 12, and a heating device 13 arranged in this order. 15, 16 and 18 are roller conveyors, 17 is a roller conveyor as a conveying line, 21 is a control panel, 22 is a hydraulic unit, 23 is an operation panel of the rolling device 12, and 24 is an operation panel of the heating device 13. Reference numeral 127 denotes a plate material after rolling.
The operation panel 24 includes condition setting means 26 and control means 27.
[0012]
FIG. 2 is a side view of a plate material manufacturing apparatus used in the vehicle body panel manufacturing method according to the present invention.
The cutting machine 11 cuts the strip loaded from the left side of the drawing to form a plate material having a predetermined length.
The rolling device 12 includes a tension device 30 and rolling means 60.
[0013]
The tension device 30 is movable in the X-axis direction (see FIG. 1), and includes X-axis movement guides 30a and 30a, an X-axis movement base 30b mounted on the X-axis movement guides 30a and 30a, and the X-axis movement base 30b. The X-axis drive means 30c and 30c shown in FIG. 1, the X-axis movement position detector 30d shown in FIG. 1, and the elements described in the next figure are used to move the axis movement base 30b in the X-axis direction.
[0014]
FIG. 3 is a perspective view of a tension device used in the method for manufacturing a vehicle body panel according to the present invention. The tension device 30 has a left clamp means 32, a right clamp means 33, and tension applying means 34, 35 on a moving table 31. .
The moving table 31 is obtained by attaching a Y-axis moving base 38 to a base 36 via a first guide 37.
[0015]
The left clamp means 32 has a housing 41 attached to the left side of the Y-axis moving base 38, and an upper pressing portion 42 is attached to the center of the housing 41 via a guide so as to be movable up and down. The pressing portion 43 is fixed, and hydraulic cylinders 44, 44 are attached to the upper portion of the housing 41. The rod 45 of the hydraulic cylinder 44 is attached to the upper pressing portion 42, and the upper pressing portion 42 is hydraulically pressed to the lower pressing portion 43. It pushes to the side.
[0016]
On the other hand, the right clamp means 33 has upper and lower pressing portions 42 and 43 and hydraulic cylinders 44 and 44 similar to the left clamp means 32 attached to a housing 47 attached to the right side of the Y-axis movement base 38 via a second guide 46. It is provided. 48 is a left clamp position detector, 49 is a right clamp position detector, and these left and right clamp position detectors 48 and 49 are, for example, a linear encoder or a linear position sensor.
[0017]
Further, the tension applying means 34 is a hydraulic cylinder 51, the attachment portion 52 of the hydraulic cylinder 51 is attached to the base 36, and the rod 53 is attached to the Y-axis movement base 38. The tension applying means 35 is a hydraulic cylinder 55, the attachment portion 56 of the hydraulic cylinder 55 is attached to the Y-axis movement base 38, and the rod 57 is attached to the right clamp means 33.
[0018]
FIG. 4 is a perspective view of rolling means used in the method for manufacturing a vehicle body panel according to the present invention. The rolling means 60 is movable up and down on a stand 61 via third guides 62 and 62 (not shown in the front). The bearing boxes 63 and 63 are fitted, and the work rolls 64 and the backup rolls 65 and 65 as upper rolls are fitted to these bearing boxes 63 and 63 via bearings (not shown), and these rolls 64, 65, Symmetrically to 65, a work roll 66 and backup rolls 67, 67 as lower rolls are fitted to a stand 61 via bearings (not shown), and reduction hydraulic cylinders 68, 68 are attached to the upper portion of the stand 61. The rods of the cylinders 68 and 68 are attached to the bearing boxes 63 and 63, and the work rolls 64 and 66 are fitted to the roll driving units 69 and 69. It is a machine. 71 is a work roll position detector, 72 is a left clamp movement limit detector, 73 is a right clamp movement limit detector, 74 and 74 are heating means, and 90 is a turntable.
[0019]
The work roll position detector 71 is, for example, a linear encoder or a linear position sensor, and the left / right clamp movement limit detectors 72, 73 are, for example, limit switches. The heating means 74 is a heat source (heater) for electromagnetic induction heating (induction heating), and is provided on the left and right of the work rolls 64 and 66.
[0020]
The turntable 90 is provided with a rotation support portion 92 at the center of the mounting base 91 and a drive portion 93 at the end. The drive unit 93 includes a guide 94 attached to the mounting base 91 and a worm speed reducer 95 that drives the guide 94.
[0021]
That is, the rolling means 60 is mounted on the turntable 90 by fitting the rolling means 60 to the rotation support portion 92 of the turntable 90 and attaching one end of the guide 94 to the rolling means 60. 96 is an origin position detector, 97 is a right rotation limit detector, and 98 is a left rotation limit detector.
[0022]
FIG. 5 is a perspective view of a heating device used in the method for manufacturing a vehicle body panel according to the present invention.
The heating device 13 includes a conveying means 99 that continuously conveys the rolled sheet material 127 horizontally, and a first sheet that extends in the sheet width direction (X-axis direction) in order to heat the sheet material 127 on the conveying means 99 linearly. The first linear heating means 101, the second linear heating means 102, the third linear heating means 103, and these first to third linear heating means 101 to 103 are arranged in the length direction of the plate 127 (Y-axis direction). Heat source moving means 104... To be moved, condition setting means 26 (see FIG. 1) for setting heating conditions, first to third linear heating means 101 to 103 and heat source moving means 104 based on the heating conditions. The control means 27 (refer FIG. 1) which controls ..., the mount frame 105 installed in a floor, and the cover 106 attached to this mount frame 105 so that attachment or detachment was possible.
[0023]
The conveying means 99 has a leg member 107 attached to the gantry 105, and rollers 108... Are rotatably attached to the leg member 107.
The roller 108 is an example, and a belt-like member such as a chain or a band may be used without using the roller 108.
[0024]
The first linear heating means 101 is formed such that a gap portion 112 is formed in the center of the main body 111 so that the plate material 127 can pass therethrough, and a heat source 113 and a reflection plate 114 are attached to the ceiling side of the gap portion 112. The heat source 115 and the reflection plate 116 are attached to the floor side of 112, and the moving range is set to the range of the length L1 of the non-rolled portion 81b in FIG.
[0025]
The second linear heating means 102 has the same configuration as the first linear heating means 101, and the moving range is set to the length L2 range of the first differential thickness portion 83 in FIG.
The third linear heating means 103 has the same configuration as that of the first linear heating means 101, and the moving range is set to the range of the length L3 of the second differential thickness portion 126 in FIG.
[0026]
Both the heat sources 113 and 115 are infrared radiation sources, for example, quartz tube type infrared bulbs.
The heating device 13 is not limited to infrared heating, and may be combustion heating using a burner (oil burner, gas burner) as a heat source.
[0027]
The heat source moving means 104 includes an electric motor 117 disposed at the end of the main body 111, a drive wheel 118 driven by the electric motor 117, a sensor 119 for measuring the rotation speed of the drive wheel 118, and the drive wheel 118. And driven wheels 121 and rails 122 and 122 for guiding the driven wheels 118 and the driven wheels 121.
[0028]
The cover 106 is provided with an inlet 123 on the rolling device side, an outlet 124 on the opposite side of the inlet 123, an opening 125 is formed on the heat source moving means 104 side, and a heat insulating material (not shown) is pasted on the inner surface.
[0029]
Next, a method for manufacturing a vehicle body panel according to the present invention will be described.
FIG. 6 is a flowchart of a method for manufacturing a vehicle body panel according to the present invention, and ST indicates a step.
ST01: A plate material is set between the upper and lower rolls of the rolling means.
ST02: Grasp both ends of the set plate.
ST03: A constant tension is applied to the gripped plate material.
ST04: Rolling with a roll to form a differential thickness portion while applying tension.
ST05: The formed plate material is continuously sent to the heating device, and each differential thickness portion is heated to a predetermined temperature by each linear heating means.
Next, ST01 to ST05 will be specifically described.
[0030]
7 (a) and 7 (b) are first explanatory views of a method for manufacturing a vehicle body panel according to the present invention.
(A): First, the plate material 81 is passed through the rolling device 12. Specifically, the left clamp means 32 reaches a predetermined position by the advance of the hydraulic cylinder 51 (rod 53) (in the direction of arrow (1)). At this time, the left clamp movement limit detector 72 prevents the left clamp means 32 from being excessively moved.
[0031]
When the hydraulic cylinders 44 and 44 (rods) on the left and right clamping means 32 and 33 are retracted (in the directions of arrows (2) and (2)), the upper pressing portion 42 is raised. On the other hand, the work roll 64 and the backup rolls 65 and 65 are lifted together with the bearing box 63 by the rolling hydraulic cylinder 68 of the rolling means 60.
[0032]
After passing the plate material 81 before rolling to the left clamp means 32 as indicated by the arrow (3), the upper pressing portion 42 of the left clamp means 32 is lowered and the thick portion 82 of the plate material 81 is gripped. On the other hand, the work roll 64 and the backup rolls 65 and 65 are pressed down on the plate member 81 by the reduction hydraulic cylinder 68.
[0033]
(B): Next, the first differential thickness portion 83 is formed by driving and rotating the work roll 64 at a predetermined roll speed. At the same time, by moving the left clamp means 32 in the tension direction (the direction of arrow (4)), the first differential thickness portion 83 is formed while applying a constant tension t to the plate material 81. When the left clamp means 32 reaches a predetermined position, it stops.
[0034]
Subsequently, in order to reversely rotate the rolling means 60, the right clamp means 33 is brought close to the vicinity of the rolling means 60, and the upper pressing portion 42 is lowered by the hydraulic cylinder 44 on the right clamp means 33 to thicken the plate 81. The part 82 is gripped. The position of the right clamp means 33 at that time is detected by the right clamp movement limit detector 73.
[0035]
FIGS. 8A and 8B are second explanatory views of the method for manufacturing a vehicle body panel according to the present invention.
(A): The work roll 64 of the rolling means 60 is reversely rotated to extend the first differential thickness portion 83 thinner. At that time, the work roll 64 is further reduced by the reduction hydraulic cylinder 68 to control the roll interval. At the same time, the Y-axis movement base 38 is reversely moved by the hydraulic cylinder 51.
[0036]
(B): A constant tension t is applied to the plate 81 by moving the right clamp means 33 by the hydraulic cylinder 55 on the Y-axis movement base 38 while moving the Y-axis movement base 38 in the reverse direction. At that time, the right clamp means 33 is positioned by the right clamp position detector 49.
Thereafter, similarly, the molding of the first differential thickness portion 83 is further repeated to mold the first differential thickness portion 83 having a predetermined thickness.
[0037]
That is, the plate material 81 is gripped by the left and right clamping means 32 and 33 and rolled while applying a tension t to the plate material 81. When the tension t acts on the first differential thickness portion 83, the first differential thickness portion 83 can be formed on a part of the thick portion 82 of the plate 81 very easily.
Further, it is possible to prevent “wrinkles” and bends that are likely to occur in the first differential thickness portion 83 due to the tension t.
[0038]
FIGS. 9A and 9B are third explanatory views of the method for manufacturing a vehicle body panel according to the present invention.
(A): The second differential thickness portion 126 is formed by the rolling means 60. Specifically, the upper pressing portion 42 of the right clamp means 33 is lifted and released, and one of the plate members 81a is extended by the work rolls 64 and 66 while applying tension by the left clamp means 32, and the second differential thickness portion. 126 is formed. 81b is the other of the board | plate material 81, and is a non-rolling part. t1 is the thickness of the non-rolled portion 81b, and t2 is the thickness of the first differential thickness portion 83.
The thickness of the second differential thickness portion 126 is t3, and the processing degree of the second differential thickness portion 126 is smaller than that of the first differential thickness portion 83.
[0039]
Here, the degree of processing corresponds to the rolling reduction. When the reduction ratio is r, the reduction ratio of the first differential thickness portion 83 is r1, the reduction ratio of the second differential thickness portion 126 is r2, the inlet side plate thickness is h1, and the outlet side plate thickness is h2, the reduction rates r and r1 , R2 can be determined by the following equation.
r (%) = [(h1-h2) / h1] × 100,
r1 (%) = [(t1-t2) / t1] × 100,
r2 (%) = [(t1-t3) / t1] × 100
[0040]
(B) is a plate 127 in which the first and second differential thickness portions 83 and 126 having different thicknesses are formed with lengths L2 and L3, respectively, and the non-rolled portion 81b is formed with a length L1 and rolling is completed. Indicates.
The plate material 127 has different material properties such as tensile strength in the non-rolled portion 81b and the first and second differential thickness portions 83 and 126 depending on the degree of processing. For this purpose, the plate 127 is then annealed.
[0041]
FIG. 10 is a fourth explanatory view of the vehicle body panel manufacturing method according to the present invention.
The plate material 127 is annealed by the heating device 13. Specifically, the condition setting means 26 (for example, the heating conditions necessary for annealing are previously set according to the thicknesses t2 and t3 as the plate thicknesses of the first and second differential thickness portions 83 and 126 of the plate material 127 and other conditions. , Keyboard).
[0042]
As an example of the heating conditions, the moving speeds Vh1, Vh2, and Vh3 for controlling the heat source moving means 104, the length L1 of the non-rolled portion 81b, the length L2 of the first differential thickness portion 83, and the second differential thickness, respectively. Length L3 of the section 126, a set temperature Th1 for controlling the first linear heating means 101, a set temperature Th2 for controlling the second linear heating means 102, and a set temperature for controlling the third linear heating means 103 Mainly Th3.
The control unit 27 includes a temperature control unit 128 and a heat source drive control unit 129.
[0043]
Based on the set temperatures Th1, Th2, and Th3, the temperature control unit 128 adjusts the temperature under the atmosphere between the heat sources 113 and 115 so that the actual temperature of the plate material becomes the set temperatures Th1, Th2, and Th3. That is, the outputs of the heat sources 113 and 115 are set so as to obtain a desired ambient temperature. In that case, you may use the signal of the thermocouple 131,132,133 attached to the board | plate material 127. FIG.
[0044]
Next, the set temperature will be described in detail.
The set temperature Th1 is the temperature of the non-rolled portion 81b, and as shown in FIG. 12B, the temperature rising rate is set to Tv1, the holding temperature is set to T5, and the holding time is set to Km1. That is, the values input at the time of setting are Tv1, T5, and Km1.
[0045]
The set temperature Th2 is the temperature of the first differential thickness portion 83, and as shown in FIG. 12B, the temperature rising rate is set to Tv2, the holding temperature is set to T1, and the holding time is set to Km1. That is, the values input at the time of setting are Tv2, T1, and Km1.
The set temperature Th3 is the temperature of the second differential thickness portion 126, and is set to be the same as the set temperature Th2.
[0046]
The heat source drive control unit 129 sets the speed of each heat source moving means 104... Based on the moving speeds Vh1, Vh2, and Vh3, while setting the distance based on the lengths L1, L2, and L3.
The rotation speed signal Ni 1 of the sensor 119 provided in the first linear heating means 101, the rotation speed signal Ni 2 of the sensor 119 provided in the second linear heating means 102, and the sensor 119 provided in the third linear heating means 103. Based on the rotation speed signal Ni3, the heat source drive control unit 129 measures each actual movement amount.
[0047]
After setting the conditions, by turning on a predetermined button of the condition setting means 26, the first to third linear heating means 101 to 103 are set at the standby position as shown in FIG. 10 based on preset conditions. Wait and wait for a workpiece at a predetermined temperature.
[0048]
Subsequently, the plate material 127 that has come out of the rolling device is transported to the inlet 123 of the heating device 13 by the roller conveyor 17 and placed on the transport means 99. Desirably, the thermocouple 131 is attached to the non-rolled portion 81b, the thermocouple 132 is attached to the first differential thickness portion 83, and the thermocouple 133 is attached to the second differential thickness portion 126.
[0049]
Thus, in the annealing process, the formed plate material 127 is continuously sent to the heating device 13, so that it does not take time to carry it from the rolling device into the heating device 13, and it does not take time to set up the annealing. Accordingly, it is possible to improve the production efficiency of the plate material 127 on which the first and second differential thickness portions 83 and 126 are formed.
[0050]
FIG. 11 is a fifth explanatory view of the vehicle body panel manufacturing method according to the present invention.
(A): The plate material 127 is placed on the conveying means 99, and the temperature of the plate material 127 is raised. Specifically, first, when the plate member 127 is stopped at a predetermined position of the conveying means 99 and the start button of the operation panel is turned “ON”, the first to third lines from the standby position to the respective start positions shown in FIG. The linear heating means 101-103 move, and the first linear heating means 101 moves as indicated by the arrow (5) at the moving speed Vh1 while heating the non-rolled part 81b between the heat sources 113, 115 having a predetermined temperature. The non-rolled portion 81b is heated (the x mark indicates that the temperature is high).
[0051]
At the same time, the first and second differential thickness portions 83 and 126 are heated by the second and third linear heating means 102 and 103. Specifically, the second linear heating means 102 moves as indicated by the arrow (6) at the moving speed Vh2 while heating the first differential thickness portion 83 between the heat sources 113 and 115 having a predetermined temperature, and the first difference The thick portion 83 is heated. The third linear heating means 103 moves as indicated by the arrow (7) at the moving speed Vh3 while heating the second differential thickness portion 126 between the heat sources 113 and 115 having a predetermined temperature, and the second differential thickness portion 126 is raised. Do warm.
[0052]
(B): Subsequently, the temperature of the plate 127 is increased. Specifically, the first linear heating unit 101 travels a predetermined distance La1 to finish the first heating of the non-rolled portion 81b, and the second linear heating unit 102 travels a predetermined distance La2. The first heating of the first differential thickness portion 83 is finished, and the third linear heating means 103 travels a predetermined distance La3 and finishes the first heating of the second differential thickness portion 126.
The predetermined distances La1, La2, and La3 are set respectively calculated from the lengths L1, L2, and L3 (see (c)) and the rotation speed signals Ni1, Ni2, and Ni3 (see (a)) by a preset program. In addition to the amount of movement, this is the range of the movement limit.
[0053]
(C): Subsequently, the first to third linear heating means 101 to 103 return again while raising the temperature of the non-rolled portion 81b and the first and second differential thickness portions 83 and 126 (thick line x mark is more) The temperature is high.) Is continued for a predetermined distance La1, La2, La3, and the second heating is finished. At the same time, it returns to the start position shown in (a).
Subsequently, from the position shown in (a), the first to third linear heating means 101 to 103 travel as indicated by arrows (5), (6), and (7), and the third heating is performed. And the annealed board | plate material 134 is obtained.
[0054]
As described above, in the annealing process, after the formed plate material 127 is stopped at a predetermined position in the heating device 13, the first linear heating means 101 corresponding to the non-rolled portion 81b is in the range of the non-rolled portion 81b. The length L1 is moved three times, the second linear heating means 102 corresponding to the first difference thickness portion 83 is moved within the length L2 three times within the range of the first difference thickness portion 83, and the second The third linear heating means 103 corresponding to the difference thickness portion 126 is moved within the length L3 three times within the range of the second difference thickness portion 126, and the non-rolled portion 81b and the first and second difference thickness portions 83 are moved. , 126 are annealed under a predetermined heating condition, it is easy to individually operate the temperatures of the first and second differential thickness portions 83, 126, and the plate material 127 is adjusted to a plate material 134 having uniform material characteristics. be able to.
[0055]
FIGS. 12A and 12B are graphs comparing annealing temperatures, showing an example, where the horizontal axis is time and the vertical axis is the temperature of the plate material.
(A) is a comparative example, which is a copy of FIG. 15 (b), and shows a temperature chart of a plate material annealed using a conventional batch-type heating furnace. The temperature T2 of the difference thickness part 142 of the thickness t2 shown in the measurement part B is higher than the temperature T1 of the difference thickness part 143 of the thickness t3 shown in the measurement part C.
[0056]
(B) is an Example and shows the temperature chart of the board | plate material annealed at the annealing process of this invention. Note that Tv1 and Tv2 indicate the rate of temperature increase, T1 indicates the holding temperature, and Km1 indicates the holding time.
As is apparent from the graph, the temperature of the first differential thickness portion 83 having the thickness t2 shown in the measurement portion B is T4, which substantially matches the temperature T1 of the second differential thickness portion 126 having the thickness t3 shown in the measurement portion C. . Further, the temperature of the non-rolled portion 81b having the thickness t1 shown in the measurement portion A is T5.
Therefore, in the annealing process of the manufacturing method of the vehicle body panel of the present invention, the temperature variation of the plate material 127 on which the first and second differential thickness portions 83 and 126 are formed can be reduced, and the first and second differential thickness portions. It is possible to adjust the plate material 127 obtained by molding 83 and 126 to a plate material having uniform material characteristics.
[0057]
13 (a) and 13 (b) are sixth explanatory views of the vehicle body panel manufacturing method according to the present invention.
(A): The annealed plate material 134 (see FIG. 11C) is formed into a predetermined vehicle body panel 136 by the press machine 135. Specifically, the annealed plate material 134 is formed in a predetermined shape with a die (not shown) in advance, and then finished with a die 137 (an upper die 137a and a lower die 137b) of the press machine 135. Complete. Here, the vehicle body panel 136 is a door panel and is hereinafter referred to as a door panel 138.
Thus, in the panel press molding process, the plate material 134 having uniform material properties processed in the previous annealing process is used, so that it can be molded into the vehicle body panel without worrying about cracks.
[0058]
(B): The door panel 138 is removed from the mold, and one press molding cycle is completed. Thereafter, the door panel 138 is conveyed to a downstream process.
[0059]
Next, another embodiment of the method for manufacturing a vehicle body panel according to the present invention will be described.
FIG. 14 is a graph showing another embodiment of FIG. 12B, and the same components as those of the embodiment shown in FIG. 11 and FIG.
Here, the case where the temperature gradient of the heating of the first and second differential thickness portions 83 and 126 is relaxed is shown. In other words, the temperature rise rate is slowed and the plate material 127 is slowly heated.
[0060]
The procedure will be briefly described. First, the heating conditions in FIG. 10 are changed, and the first and second differential thickness portions 83 and 126 are heated to the temperature T6 while the temperature is increased at the temperature increase rate Tv3. At T6, the holding time is Km2. If it is temperature T6, the distortion at the time of a heating can be prevented. That is, the temperature difference between the place where the temperature reaches T6 and the place where the temperature rise is slow does not suddenly increase, and the amount of thermal expansion at this time is the amount of strain in the elastic region, and no residual strain occurs. Further, distortion and wrinkle of the plate material 127 can be prevented. Further, by holding only the holding time Km2, the temperature of the place where the temperature rises slowly is increased to T6 and the temperature is made uniform.
[0061]
Subsequently, after holding for the holding time Km2, the temperature is raised to temperature T1. Between the temperature T6 and the temperature T1, the temperature difference does not increase suddenly, no residual strain occurs, and distortion and wrinkle of the plate material 127 can be prevented.
[0062]
Thus, in the annealing process of the manufacturing method of the vehicle body panel of the present invention, after the formed plate material 127 is stopped at a predetermined position in the heating device 13, the first linear heating means 101 corresponding to the non-rolled portion 81b is used. The inside of the length L1 of the non-rolled portion 81b is moved three times, and the second linear heating means 102 corresponding to the first thickness difference portion 83 is moved within the length L2 of the first thickness difference portion 83 three times. The third linear heating means 103 corresponding to the two differential thickness portions 126 is moved three times within the length L3 of the second differential thickness portion 126, and the non-rolled portion 81b and the first and second differential thickness portions 83 and 126 are moved. Since annealing is performed under a predetermined heating condition, when the temperature gradient of heating of the first and second differential thickness portions 83 and 126, which is one of the heating conditions, is relaxed, the first and second differences are caused by the relaxed temperature gradient. The thick portions 83 and 126 can be heated. As a result, the temperature gradient of heating of the first and second differential thickness portions 83 and 126 having different plate thicknesses can be relaxed to prevent the occurrence of residual strain, and the plate material 127 can be prevented from being distorted or wrinkled.
[0063]
In addition, the temperature of FIG.12 (b) shown in embodiment of this invention and FIG. 14 is an example.
In FIG. 11, the first to third linear heating means 101 to 103 both start moving at the same time and finish the first and second heating at the same time, but this heating condition is an example, The start and end timings are arbitrary.
[0064]
The number of movements of the first to third linear heating means 101 to 103 is not limited to three, and the number of movements is arbitrary.
The plate material manufacturing apparatus 10 is an example, and the configuration of the apparatus is arbitrary.
After the strip is cut, the plate is rolled by the rolling device 12, but conversely, the plate may be separated from the strip by the cutting machine 11 after rolling. In that case, the arrangement position of the cutting machine 11 is changed.
[0065]
【The invention's effect】
The present invention exhibits the following effects by the above configuration.
In claim 1, a plate material setting step of setting a plate material between upper and lower rolls of the rolling means, a gripping step of gripping both ends of the set plate material, a tension applying step of applying a constant tension to the gripped plate material, and tension The difference thickness part forming step of forming the difference thickness part by rolling with the upper and lower rolls, and the formed plate material is continuously sent to the heating device provided in the transport line, and stopped at a predetermined position, and annealing step of annealing a plurality of times moved so with each of the different thickness portion a predetermined heating condition within the range of each different thickness portion linear heating means each corresponding to each different thickness portion, press the annealed sheet And a panel press forming process for forming a predetermined body panel.
The annealing step, after stopping the molded sheet at a predetermined position in the heating device, the difference in each plurality of times to move the range for each different thickness portion linear heating means each corresponding to each different thickness portion Since the thick part is annealed under a predetermined heating condition, the inside of the range of one differential thickness part can be heated by the movement of one linear heating means, and the temperature control of each differential thickness part is easy. . Therefore, the plate material formed with the differential thickness portion can be adjusted to a plate material that is annealed and has uniform material characteristics.
[0066]
Further, in the annealing step, after stopping the molded sheet at a predetermined position in the heating device, a plurality of times to move the range for each different thickness portion linear heating means each corresponding to each different thickness portion respectively Since the difference thickness portion is annealed under a predetermined heating condition, it can be heated by relaxing the temperature gradient of the difference thickness portion heating, and distortion at the time of heating can be prevented. Accordingly, it is possible to prevent distortion and wrinkling of the plate material formed with the differential thickness portions having different plate thicknesses during annealing.
[Brief description of the drawings]
FIG. 1 is a plan view of a plate material manufacturing apparatus used in a vehicle body panel manufacturing method according to the present invention. FIG. 2 is a side view of a plate material manufacturing apparatus used in a vehicle body panel manufacturing method according to the present invention. FIG. 4 is a perspective view of a tension device used in a method for manufacturing a vehicle body panel. FIG. 4 is a perspective view of rolling means used in a method for manufacturing a vehicle body panel according to the present invention. FIG. 6 is a flowchart of a vehicle body panel manufacturing method according to the present invention. FIG. 7 is a first explanatory diagram of a vehicle body panel manufacturing method according to the present invention. FIG. 9 is a third explanatory diagram of a method for manufacturing a vehicle body panel according to the present invention. FIG. 10 is a fourth explanatory diagram of a method for manufacturing a vehicle body panel according to the present invention. Fig. 12 is a fifth illustration of the manufacturing method. FIG. 13 is a sixth explanatory diagram of a method for manufacturing a vehicle body panel according to the present invention. FIG. 14 is a graph showing another embodiment. FIG. 15 is a diagram showing heating of a conventional plate. ]
DESCRIPTION OF SYMBOLS 13 ... Heating device, 17 ... Conveyance line (roller conveyor), 60 ... Rolling means, 64 ... Upper roll (work roll), 66 ... Lower roll (work roll), 81 ... Plate material before rolling, 81b ... Non-rolling , 82 ... both ends (thick part) of the plate material, 83 ... first differential thickness part, 101 ... first linear heating means, 102 ... second linear heating means, 103 ... third linear heating means, 126 ... 2nd differential thickness part, 127 ... Molded plate material (plate material after molding), 134 ... 1st differential thickness part, 135 ... Press machine, 136 ... Body panel, L1-L3 ... Range (length) for each differential thickness part T ... tension.

Claims (1)

A plate material setting step for setting a plate material between upper and lower rolls of the rolling means, a gripping step for gripping both ends of the set plate material, a tension applying step for applying a constant tension to the gripped plate material, The difference thickness part forming process in which the difference thickness part is formed by rolling with upper and lower rolls, and the formed plate material is continuously sent to the heating device provided in the conveying line, stopped at a predetermined position, and then for each difference thickness part. An annealing process in which each corresponding linear heating means is moved a plurality of times within the range of each differential thickness portion and each differential thickness portion is annealed under a predetermined heating condition, and a predetermined body panel is formed by using the press for the annealed plate material A panel press forming process for forming a vehicle body panel.

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