JP2000005834A - Successive form processing method for thin plate elasticity plastic material, flange part, and device to be used for it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a mold expense, a mold changing expense and reduce a mold storage space by carrying out a form processing of a flange part which being composed of many kinds thin plate elastic plasticity materials, whose three dimensional shapes are different from each other, by using a small, general purpose forming mold, without using a large, exclusive mold. SOLUTION: A work flange part is made to pass through between a pair of small size, general purpose forming molds 29 which have forming faces to be changed smoothly in succession. Simultaneously, a processing force to be generated by a vibration load generating device 7 is repeatedly applied to the flange part via the forming mold 29 for carrying out the forming processing by accumulating a micro plastic deformation in succession along the flange part. At this time, the processing force may be applied by changing the force in proportion to the variation of the processing contents. Also, when necessary, a local single formation processing can be parallely carried out using a separate forming mold being built-in on the same processing head.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for sequentially forming a flange portion formed in a thin elasto-plastic body and an apparatus used for the method. While repeatedly applying the force generated by the vibration load generating device through the pair of forming dies, by passing the processing target flange portion of the sheet-shaped elasto-plastic body between the pair of forming dies, The present invention relates to a method for sequentially forming a flange portion and an apparatus used for the method.

[0002]

2. Description of the Related Art Conventionally, a molding die having a molding surface that continuously changes a vibration load generated by a vibration load generating device having a load transmitting portion from a shape before processing to a desired shape after processing is used. Japanese Patent Application Laid-Open No. H9-220626 can be cited as a prior art for sequentially forming a flange portion while transmitting the flange portion to a workpiece through a work.

That is, in Japanese Patent Application Laid-Open No. 9-220626, a flange 1a which is bent above a peripheral edge of a first sheet metal work 1 positioned and mounted on a substantially horizontal upper surface of a mold 3 is replaced with the flange 1a. Of the second sheet metal work 2 superimposed on the first sheet metal work 1 by pressing the outer surface side of the second sheet metal work 1 on the outer surface side thereof.
A hemming method for a sheet metal work in which the flange portion 1a is pressed against the peripheral portion of the second sheet metal work 2 to form a full hem with a predetermined hem thickness.
When the a is sequentially bent in its extending direction, the hem blade 4 having a pressing curved surface 4e on the lower surface corresponding to the angle change of the flange portion 1a from the beginning to the end of the bending from the beginning to the end of the bending is moved to the robot arm 6 by vertical hammering. When hemming is performed by attaching to the servo hammering unit 5 which is supported as possible, the teaching and playback functions of the robot are utilized.

[0004]

However, in the method of hemming a sheet metal work as disclosed in Japanese Patent Application Laid-Open No. 9-220626, the hemming blade 4 receives the processing force of the hem blade 4 via the works 1 and 2 during hemming. In addition, a large-sized mold 3 dedicated to the work, which serves as a reference for obtaining the movement trajectory data of the robot and is in contact with the entire hemming portion on the periphery of the work, is a necessary condition. Therefore, there is a problem that the cost of the mold for performing the hemming process is increased and a large space for storing the mold 3 is required.
In addition, when a large number of types of workpieces are produced, there is a problem that, in addition to a problem of a die cost and a storage space, a time required for exchanging the die 3 due to a change of a work to be produced and its cost increase. Further, when there are surfaces forming negative angles with each other in the hemming processing surface of the work, the surface of the mold 3 on which the work is placed and which receives the processing force also forms a negative angle, so that the work can be detached. Therefore, there are problems such as the need to divide the mold structure and the steps.

In Japanese Unexamined Patent Publication No. 9-220626, a servo hammering unit 5 is provided on a robot arm 6, a hem blade 4 is attached to the unit 5, and a flange 1a of the first sheet metal work 1 is attached to the hem blade 4. Therefore, all of the processing force is received by the mold 3 below the work, and all of the processing reaction force is received by the robot arm 6. Therefore, in addition to the problem that the robot is easily damaged, a large force is required to maintain the relative position between the mold 3 and the robot, which makes the equipment heavy and increases the cost. In addition, there is a problem that a large force is required for the mold 3 to hold the work 1 and that the work 1 is likely to be damaged.

The present invention has been made in order to solve the above-mentioned problems, and has a structure in which the cross-sectional shapes are almost common and three-dimensional shapes are different from each other, as in the case of hemming a general automobile door or hood. Forming of flanges of various types of thin elasto-plastic materials without using large and dedicated molds,
By using a small and general-purpose molding die, the cost of the die and the cost of replacing the die are reduced, the space for storing the die is reduced, and the thin elasto-plastic body itself and the automatic motion device such as a robot The purpose is to reduce wear and damage.

[0007]

According to the present invention, there is provided the following means for solving the above-mentioned problems.

[0008] The invention according to claim 1 is a method for performing a sequential forming process using a pair of small and general-purpose forming dies which relatively move along a flange portion of a thin plate-shaped elasto-plastic body. When a force for forming is applied to the target flange portion of the thin plate-shaped elasto-plastic body via the mold, both the dies of the pair of forming dies are placed on the inlet side where the flange portion enters, and the flange portion is provided. Has a molding surface at least partially in contact with the surface before processing, and at the exit side where the flange portion comes out, at least partially contacts the desired shape after processing of the flange portion, or has elastic recovery. Between the molding surface on the inlet side and the molding surface on the outlet side, the flange portion is smooth along the direction passing between the molding dies. And the mold becomes the franc When a force required for molding is repeatedly applied to the flange portion while relatively moving along the portion, the flange portion is sequentially deformed from a shape before processing to a desired shape after processing while being in contact with the flange portion. Between a pair of forming dies having a continuous forming surface, a flange portion to be processed of the thin plate-shaped elasto-plastic body is passed from the inlet side to the outlet side, and at the same time, the flange portion is interposed through the pair of forming dies. The force for shaping generated by the vibration load generating device is repeatedly applied to the thin plate-shaped elasto-plastic body, while accumulating minute plastic deformation sequentially along the flange portion, before shaping the target flange portion. From one to the desired shape after processing.

According to a second aspect of the present invention, a force necessary for causing plastic deformation for forming to be formed on a flange to be processed of a thin elasto-plastic body is repeatedly applied through the pair of forming dies. While performing relative movement between the pair of forming dies and the sheet-shaped elasto-plastic body along the flange portion, the movement of at least one of the pair of forming dies or the sheet-shaped elasto-plastic body is automatically controlled. It was done.

The invention according to claim 3 is such that the movements of both the pair of forming dies and the thin plate-shaped elasto-plastic body are automatically and cooperatively controlled.

According to a fourth aspect of the present invention, in automatically controlling at least one of the pair of forming dies and the thin plate-shaped elasto-plastic body, at least one of a relative position, a relative posture, and a relative speed is automatically controlled. It is something to do.

Further, the invention according to claim 5 is to provide a small-sized and general-purpose forming die capable of performing sequential forming along a flange of a thin plate-shaped elasto-plastic work having various three-dimensional free-form surfaces. The relative degree of freedom of relative movement between the pair of forming dies and the thin plate-shaped elastoplastic body is 3 or more in position and 3 or more in posture, that is, 6 or more in total.

According to a sixth aspect of the present invention, in addition to the automatic control of the relative movement between the pair of forming dies and the thin elasto-plastic body, the processing of the thin elasto-plastic body is coordinated with the automatic control. The magnitude of the force generated by the vibration load generator that repeatedly applies the force for forming to the target flange portion via the pair of forming dies, the repetition period, and the relative movement between the pair of forming dies and the thin plate-shaped elasto-plastic body At least one of the processing conditions of the speed is automatically controlled so as to be changed in accordance with the change of the processing content along the flange portion to be processed.

According to a seventh aspect of the present invention, there is provided a pair of forming dies for successively forming a flange while moving relatively along the flange of the elasto-plastic thin plate. When a force for forming is applied to the processing target flange portion of the thin plate-shaped elasto-plastic body through a pair of general-purpose forming dies, both dies of the pair of forming dies enter the flange portion. Side has a molding surface at least partly in contact with the surface before processing of the flange portion, and at the exit side where the flange portion comes out, at least partly has a desired shape after processing of the flange portion. Has a molding surface that is in contact with or indents by an amount of elastic recovery, and the flange portion is provided between the pair of molding dies between the molding surface on the inlet side and the molding surface on the outlet side. Slides continuously along the direction of passing When the forming die repeatedly applies a force necessary for forming to the flange portion while relatively moving along the flange portion, the flange portion is processed from the shape before processing while being in contact with the flange portion. A continuous molding surface is formed so as to be sequentially deformed to a desired shape.

The invention according to claim 8 is characterized in that a vibration load that periodically fluctuates between a predetermined upper limit value and a lower limit value of a load at a predetermined cycle is generated, and a load transmission unit of the device is provided. 7. The method of claim 1, 2, 3, 4, 5 or 6, wherein the method is capable of transmitting the vibration to the outside and changing the amplitude of the load transmitting portion depending on the load deformation characteristics of the object transmitting the vibration load. 7. The pressurizing device according to claim 6, wherein a value of a vibration load generated by said device, a period thereof, and a processing condition of an amplitude of said load transmitting portion are changeable, thereby realizing the method of claim 6, and Sequential molding by allowing the transmission part to be displaced in a direction opposite to the direction in which the vibration load for sequential molding is transmitted and larger than the amplitude setting range when transmitting the vibration load for sequential molding. Local irregularities that are not compatible with Even if that is one which enables combination to be single molding using a mold dedicated to 該局 unit.

According to a ninth aspect of the present invention, there is provided an operating section of a vibration load generating device having a load transmitting section, one of a pair of forming dies, and a relative movement of the pair of forming dies. The fixed side of the guiding device for guiding is attached to one frame,
Of the pair of molding dies, the other molding die is attached to the movable part of the guide device, so that the pair of molding dies can relatively move on a trajectory required for processing by the guide device, and further, The vibration load and the displacement are transmitted from the load transmitting portion of the vibration load generator to the molding die attached to the movable side.

According to a tenth aspect of the present invention, the processing head of the ninth aspect further comprises a pair of at least one molding surface having a shape different from that of the processing head having the requirements of the first aspect. A mold is attached.

According to an eleventh aspect of the present invention, the processing head according to the ninth or tenth aspect is further provided with one or more pairs of forming dies for local single-shot forming other than the forming dies for sequential forming. .

[0019]

According to the working method of the present invention, when the flange portion of the work passes between the pair of forming dies, it smoothly and continuously has the pair of forming dies. Repeatedly receiving the force that causes minute plastic deformation through the changing forming surface, the accumulation of this minute plastic deformation causes the shape from before processing to the desired shape after processing, continuously and smoothly along the flange. It is formed sequentially. At this time, the flange portion of the work undergoes stretch flange formation and contraction flange formation, but undergoes plastic deformation smoothly and continuously over the entire surface from the entrance side to the exit side in the molding die each time pressing is performed, Since the amount of plastic deformation due to one press is small, the length from the entrance to the exit of the mold can be reduced without causing cracks and wrinkles during molding. Therefore, according to the method of the present invention, it is possible to form a workpiece having a curved surface having a three-dimensionally larger curvature.

In the processing method according to any one of claims 2 to 4, the trajectory, relative posture and relative speed at which the flange portion of the work relatively moves while passing through the pair of forming dies are determined by a playback method, a program control method, or the like. Thus, it is set in advance according to the processing content, and is automatically reproduced at the time of processing. In addition, the vibration load conditions for molding transmitted to the work via the mold while the flange of the work passes through the pair of molds are also set in advance according to the processing content and are automatically reproduced at the time of processing Therefore, the same processing content can be repeatedly executed, or can be switched to a different processing content and executed.

According to a fifth aspect of the present invention, the relative position and the relative attitude in the three-dimensional space are respectively 3 or more, and a total of 6 or more.
By having the relative motion function with the above-mentioned degree of freedom, it is possible to specially contact the entire peripheral part even with the processing contents such as hemming of the peripheral part of various three-dimensional free-form surfaces such as doors and hoods of general automobiles. Without using a mold.

According to the processing method of the sixth aspect, the magnitude of the vibration load can be set according to the change in the curvature along the flange portion of the work, the flange length, the plate thickness, and the change in the processing content of the number of plates.
Processing conditions such as frequency, amplitude, and feed rate are appropriately changed and set in advance, and processing is performed while automatically reproducing the processing conditions.

In the case where the vibration load generating device according to claim 8 is used in combination with the forming die according to claim 7 for the sequential forming of the work flange, the processing contents as described in the operation of claim 6 can be obtained. In addition to performing sequential forming while changing processing conditions in response to changes, local single-shot forming that requires a larger stroke than during sequential forming, or with a pair of forming dies wide open While observing the relative relationship between one of the molding dies and the periphery of the workpiece, it is possible to teach an automatic motion device carrying the molding dies, for example, an industrial robot, or to check the trajectory.

According to a ninth aspect of the present invention, when the machining head is carried by an automatic motion device, for example, an articulated industrial robot having six joints, and is used for sequential molding of a work flange, a pair of molding heads is formed. Since the processing is performed by sandwiching the flange of the work with the tip of the beak by the mold, the conventional method can not be formed from only one direction due to the negative angle, so the processing equipment and processing steps become complicated Processing can be done with a single setting. In addition, the component in the pressing direction of the processing force to be transmitted to the work via the pair of forming dies is absorbed by one frame holding the forming dies, and is transferred to the automatic motion device and the holding portion of the work. Is not transmitted. Therefore, deformation and wear of the automatic motion device, the work holding device, and the work itself are reduced.

The working head of claim 10 further enhances the versatility of the working head of claim 9. For example,
In addition to the usual folding type hemming as shown in FIG. 6 on the bonnet peripheral portion of the automobile, the flange portion facing the occupant may be subjected to a ball-shaped hemming process in order to improve safety in a collision. . Even in such a case, if the processing head of claim 10 is used, two types of hemming processing can be performed with only one set of processing head and the automatic motion device.

The processing head according to claim 11 further expands the versatility of the processing head according to claims 9 and 10. For example, even in a case where sharp irregularities that are not compatible with the sequential molding method of claim 1 are locally mixed, such as hemming of a character line portion in a general automobile door, By switching to a dedicated single-shot mold for that portion attached to the same processing head and performing single-shot molding, the entire hemming process can be performed with only one set of the processing head and the automatic motion device.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
7 will be described in detail with reference to FIG.

1, 2 and 3, reference numeral 1 denotes an articulated industrial robot corresponding to an automatic motion device.
A frame 3 constituting the processing head 2 is provided on the final shaft 1a, and a main portion 3a is formed in a substantially L-shape. A guide rail 4a is fixed to the body of the frame 3 in the vertical direction in the figure, and a moving member 4b is provided movably in the vertical direction in the figure so as to sandwich the guide rail 4a. The guide device 4 is constituted by the guide rail 4a and the moving member 4b. A bracket 5 extending in the same direction as the lower end of the frame 3 is fixed to the moving member 4b, and the length of the tip is approximately the same as the length of the tip of the frame 3.

The frame 3 is provided with a hydraulic cylinder 7 above the guide device 4, a hydraulic chamber 9 connected to a servo valve 8 is connected to a drive chamber side above the cylinder 7, and a return chamber below. On the side, a hydraulic pipe 11 communicating with the electromagnetic switching valve 10 is connected. A bracket 5 of the moving member 4b is fixed to a lower end of a piston rod 7b having a piston 7a of the hydraulic cylinder 7 via a piston pin 7c. The bracket 5 is synchronized with the movement of the piston 7a along the guide rail 4a. It is designed to move.

The hydraulic cylinder 7 has a pressure head 12
The pressure head 12 is connected to a pressure head signal line 15a which leads to a pressure head amplifier 14. The servo valve 8 is connected to a servo amplifier signal line 18 leading to a servo amplifier 17. Reference numeral 19 denotes a limit switch, to which a limit switch signal line 20 connected to the servo amplifier 17 is connected. Also,
Reference numeral 21 denotes a hydraulic pipe. One end of the hydraulic pipe 21 is connected to the servo valve 8, and the other end has the same diameter as the pressure reducing valve 25 and the electromagnetic switching valve 1.
Connected to 0. On the other hand, it is also connected to the accumulator 24. Reference numeral 22 denotes a channel setting device included in the controller 13. Reference numeral 13a denotes a signal line connecting the articulated robot 1 and the controller 13.
Is a signal line connecting the servo amplifier 17 and the channel setting unit 22.

An oil tank 23 is arranged in the vicinity of the articulated robot 1, and a hydraulic pipe 11 and an electromagnetic switching valve 10 to which the hydraulic pipe 21 is connected are provided above the oil tank 23. The oil tank 23 has an accumulator 24 and a pressure reducing valve 2.
5, pump unit 26, throttle valve 27, relief valve 28
Etc. are provided. A filter 26 a is provided in a path leading to the pump unit 26, and a check valve 8 a is provided in a path leading to the servo valve 8. A check valve 8b is provided in a path returning from the servo valve 8 to the oil tank 23 in a direction opposite to the check valve 8a.

The frame 3 and the bracket 5 are provided with a pair of molding dies 29 as shown in FIG.
The pair of molding dies 29 is composed of an upper mold 29a and a lower mold 29b, and molding surfaces 29c and 29d for successive molding are formed on inner surfaces thereof. Then, the molding surfaces 29c, 29d of both molding dies 29a, 29b
Are formed with four screw holes 30a on the opposite surfaces, respectively, so that they can be attached to the frame 3 and the bracket 5 by bolts 30, respectively.

The molding surfaces 29c and 29d of the pair of molding dies 29
The workpiece M includes a first member Ma and a second member Mb as shown in FIGS.
When a force for forming is applied to the processing target flange portion Mc, the forming surfaces 29e and 29f such that at least a part thereof comes into contact with the surface before processing of the flange portion Mc on the entrance side where the flange portion Mc enters. Is formed, and at least part of the flange Mc is in contact with a desired shape after processing on the outlet side where the flange Mc exits, or
Formed surfaces 29g and 29h are formed so as to bite by the amount of elastic recovery.

The inlet-side molding surfaces 29e, 29e
Between f and the molding surfaces 29g and 29h on the outlet side, there is provided a molding surface which changes continuously and smoothly, so that plastic deformation is caused while relatively moving along the flange portion Mc of the workpiece M to be machined. When the necessary force is repeatedly applied, the flange portion is sequentially deformed into a desired shape.

In FIG. 1, a general-purpose positioning device 31 for a work M is disposed in front of the articulated robot 1. The positioning device 31 is provided with a support base 33 that is rotatable and fixable on a base 32 formed in a disk shape, and has XX directions orthogonal to each other at four locations on its upper surface.
A general-purpose positioning jig 34 that can be moved and fixed in the YY direction and the ZZ direction is provided. A clamp 36 operated by a cylinder 35 is provided above the general-purpose positioning jig 34.
6, the work M placed on the general-purpose positioning jig 34 is fixed. Further, the pedestal 32
Is connected to a wiring 37 extending from the controller 13, and the movement of the support 33, the position adjusting jig 34, and the clamp 36 is controlled by a signal from the controller 13.

Next, a mechanism for generating and controlling a vibration load will be described based on the hydraulic circuit of FIG. 3 and the conceptual diagram of FIG. In the hydraulic circuit of FIG. 3, the pump unit 26 is operated to pump hydraulic oil (not shown) from the oil tank 23 through the filter 26a, and the hydraulic pipe is connected through the P port and the C2 port of the check valve 8a and the servo valve 8. Hydraulic oil is sent from 21 and 9 to the drive chamber side of the hydraulic cylinder 7. At this time, if the hydraulic pressure of the circuit after the pump unit 26 exceeds the set value of the relief valve 28, the operating oil escapes to the atmospheric pressure side through the relief valve 28, and the pressure of the circuit is maintained at the set value of the relief valve 28. . As a result, a constant load is generated between the pair of forming dies 29 via the piston 7a and the piston rod 7b of the hydraulic cylinder 7.

The servo valve 8 operates so as to alternately repeat conduction between the C2 port and the P port and between the C2 port and the R port by the oscillating current from the servo amplifier 17. Since the R port of the servo valve 8 is open to the atmosphere side, the pressure of the hydraulic circuit to the drive chamber side of the hydraulic cylinder 7 oscillates between the set pressure and the atmospheric pressure, and its frequency is controlled by the servo amplifier. 17 is the same as the set value of the frequency of the oscillating current.

A pressure head 12 is mounted on the drive chamber side of the hydraulic cylinder 7 and detects the internal pressure to convert the pressure into an electric signal. The signal is transmitted via a signal line 15a, a pressure head amplifier 14 and a signal line 15b. The change in the internal pressure is transmitted to the servo amplifier 17 to control the upper and lower limits of the internal pressure. The magnitude and frequency of the oscillating current sent from the servo amplifier 17 to the servo valve 8 via the servo amplifier signal line 18 are set in advance on the servo amplifier 17 side, and the controller 13 of the articulated robot 1 in FIG. From the channel setting device 22 and the signal received in response to the movement of the articulated robot 1 via the signal line 13a.

When the servo valve 8 is switched so that the C2 port and the R port are conducted, and the electromagnetic switching valve 10 is switched so that the C2 port and the P port are conducted, the hydraulic pipe 11 is switched.
Hydraulic fluid is sent from the hydraulic cylinder 7 to the return chamber side of the hydraulic cylinder 7,
The space between the pair of molds 29 is increased. This movement is stopped by a signal from the limit switch 19 which is activated by the contact of the piston rod 7b.

Next, a method of sequentially forming the flange portion of the work M will be described. 6 and 7, M is a thin plate-shaped elasto-plastic body (hereinafter, referred to as a work), and the work M includes a first member Ma and a second member Mb as shown in FIG. The end face of the member Mb is L
It is formed on the flange part Mc to be machined in the shape of a letter. Then, in a state where the first member Ma is set on the second member Mb, the first member Ma is placed on the general-purpose positioning jig 34 of the general-purpose positioning device 31, and is sandwiched and positioned by the operation of the cylinder 35 and the clamp 36. At that time, it is not necessary to operate and position all the clamps 36, and only the necessary clamps 36 can be operated.

Next, as shown in FIG.
3, the support base 33 and the general-purpose positioning jig 34 are positioned at predetermined positions through signal lines 37, and a signal is sent to the articulated robot 1 through signal lines 13 a, and the upper mold 29 a of the pair of molding dies 29 is transmitted. And the lower mold 29b is in contact with the processing target flange portion Mc of the work M in an opened state. Then, the pump unit 26 shown in FIG. 3 is operated to pump up the operating oil via the filter 26a,
Hydraulic oil is sent from the hydraulic pipes 21 and 9 to the drive chamber side of the hydraulic cylinder 7 through the port and the C2 port. As a result, the pair of forming dies 29 move in the closing direction by being pushed by the piston 7a and the piston rod 7b of the hydraulic cylinder 7, and a constant load is generated between the pair of forming dies 29.
This load is maintained at a fixed value regardless of the shape of the workpiece before and after processing and the processing rigidity.

The servo valve 8 is driven by the oscillating current from the servo amplifier 17 so that the C2 port, P port and C2
The connection between the port and the R port operates so as to be alternately repeated, and a signal is sent from the controller 13 to the articulated robot 1 through the signal line 13a. As shown in FIG. While the load is repeatedly applied, the support base 33 is rotated by a signal from the controller 13 and the pair of molding dies 29 relatively move along the machining target flange portion Mc. At this time, the articulated robot 1 or both the articulated robot 1 and the support 33 can be moved. As a result, a small plastic deformation amount is sequentially accumulated along the processing target flange portion Mc,
The processing target flange portion Mc is sequentially formed from a shape before processing to a desired shape after processing, as shown in FIGS. 7A to 7C.

Then, in a state where the work M is sequentially formed into a predetermined shape, the servo valve 8 is switched by a signal from the controller 13 so that the C2 port and the R port are conducted, and the electromagnetic switching valve 10 is switched to the C2 port. When switching is performed so that the P port is conducted, hydraulic oil is sent from the hydraulic pipe 11 to the return chamber side of the hydraulic cylinder 7, and the interval between the upper mold 29 a and the lower mold 29 b of the pair of molding dies 29 increases. Then, the movement is stopped by a signal from the limit switch 19 operated by the contact of the piston rod 7b. Also, a pair of molding dies 29
Is released, the movement of the general-purpose positioning device 31 is stopped by a signal from the controller 13, and the clamp 36 is released. The articulated robot 1 also returns to a predetermined position and stops.

Next, another embodiment of the processing head used in the apparatus of the present invention will be described with reference to FIG. In the configuration of FIG. 8, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 8, reference numeral 50 denotes a bracket formed in a T-shape. The bracket 50 is provided below the frame 3. A bracket 5 provided on the frame 3 is provided on the piston rod 7a of the hydraulic cylinder 7.
A bracket 51 having the same shape as that of the bracket 50 is connected by a piston pin 7c, and moves toward and away from the bracket 50 by the operation of the piston rod 7b.

A lower die 29b having the same structure as that shown in FIG. 4 is provided at the front end of one bracket 50, and an upper die 29a having the same structure as that shown in FIG. The pair of molds 29a and 29b constitute a pair of molding dies 29 for performing successive molding. In addition, a lower mold 52b is provided at one end of the one bracket 50 extending to the side, and an upper mold 52a is provided at one end of the other bracket 51 extending to the side.
On the opposing surfaces, a forming surface for performing a sequential forming process of a shape different from the above or a local single-shot forming process is formed, and a pair of forming dies A52 is constituted by both forming dies 52a and 52b. I have. Further, a pair of molding dies B53 having molding surfaces different from those described above are provided at the other ends of the one bracket 50 and the other bracket 51 extending laterally for the same purpose as described above.

When the processing target flange portion Mc of the work M is sequentially formed by the processing head configured as described above, one of a pair of the sequential forming dies is selected and the sequential forming is performed according to the above-described method. Perform processing. Also, if there is a local uneven shape in the flange part of the workpiece that does not fit in the sequential forming process, select a local single-shot mold to generate a larger stroke than in the above-mentioned sequential forming. Local single-shot molding can be performed in combination.

[0048]

Since the present invention is configured as described above, it has the following effects.

For example, doors and hoods of general automobiles differ in vehicle type and appearance, but often have the same cross-sectional shape cut in the normal direction on the outer periphery of the hemmed portion on the periphery. In such a case, the forming surfaces of the pair of forming dies used for forming the flange portion of the work are surfaces at least partially in contact with the shape before the work is formed on the inlet side of the work, and are formed on the outlet side of the work. A surface that at least partially touches or cuts into the desired shape after processing of the work by an amount of elastic recovery, a surface that smoothly changes continuously between the surfaces, and a vibration load is applied to the flange portion of the work via the formed surface. By carrying out the sequential forming while accumulating the minute plastic deformation amount obtained by this, the pair of forming dies can be made compact, and it can be widely used for more diverse three-dimensional free-form workpieces. Can be used. Therefore, the production cost, replacement cost, and storage space of the molding die can be significantly reduced as compared with the method according to the related art in which a dedicated molding die is used for each work in contact with substantially the entire flange portion to be processed of the work.

The posture and speed of the relative movement between the pair of small and general-purpose forming dies and the work, and the conditions of the vibration load for the sequential forming are controlled by automatic movement such as a playback method or a program control method. By repeatedly executing the processing with the contents set in advance by the apparatus, it is possible to economically perform the repetitive processing of various works, as compared with the method according to the related art in which a dedicated mold is used for each work.

By setting the degree of freedom of the relative movement between the pair of forming dies and the workpiece by the automatic movement device to 3 or more in position and 3 or more in posture with respect to a three-dimensional space, a total of 6 or more,
Since the sequential forming process along a flange portion of a three-dimensional free-form work such as a general car door or bonnet can be generally and automatically performed by a pair of small forming dies, a method according to the prior art is used. As described above, the economy is improved as compared with the case where a dedicated molding die is used for each work in contact with substantially the entire flange portion to be processed of the work.

Further, by sequentially forming while changing the processing conditions automatically in accordance with the change in the processing contents along the flange portion of the work, it is possible to form the stretch flange formed by the same forming die, In addition to increasing the possible range of flange forming, improving the versatility of the mold, the processing speed is optimized, and it is not necessary to set the entire feed speed slower to the most severe part of the processing, Overall processing time can be reduced.

Regarding the function of the vibration load generator,
Automatically control the processing conditions such as the magnitude, amplitude, and period of the vibration load. In addition to the repetitive pressurization with a small amplitude that performs ordinary sequential forming, a single pressurization function with a larger stroke has been added. In the case where a shape that is not compatible with the sequential forming process by a pair of forming dies is locally mixed in the processing target flange portion of the work, it is possible to switch to a dedicated forming die in that portion and perform single shot forming, This increases the versatility of the pressurizing device and eliminates the need for separate processing steps, so that equipment costs and processing time can be reduced. In addition, by adding a function that strokes in a direction opposite to the pressure for forming, which is larger than that during forming, a pair of forming dies can be widely opened and one of the forming While visually observing the relative relationship with the part, it is possible to teach an automatic exercise device carrying the molding die, for example, a playback-type industrial robot, and to confirm a trajectory.

Further, the processing head for performing the sequential forming processing is
Since the work is sandwiched by the tip of the beak, when the work is carried on an automatic motion device such as a six-axis articulated industrial robot and used for the sequential forming of the work flange, the prior art According to the method described above, molding is not possible from only one direction due to the negative angle, and even in molding processing that complicates processing equipment and processing steps, molding can be performed with a pair of molding dies by one setting, and Of the processing force to be transmitted to the work via the forming die, the component in the pressing direction is absorbed by one frame holding the forming die, and is not transmitted to the automatic motion device or the work holding portion.
Therefore, wear and deformation of the automatic motion device, the work holding device, and the work itself are reduced, which leads to improvement of the life of the device and the quality of the product.

Further, by attaching two or more types of sequential forming dies to the tip of the processing head, or by mounting the sequential forming die and the local single-shot forming die, not only the versatility of the processing head is improved, but also it is improved. The versatility of related equipment, such as the above-described automatic exercise equipment, is also increased.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of an apparatus used for a sequential forming method according to the present invention.

FIG. 2 is a cross-sectional side view of a part of a processing head used in a sequential forming method according to the present invention.

FIG. 3 is a hydraulic circuit of a vibration load generating device used in a sequential forming method according to the present invention, and a control system diagram thereof.

FIG. 4 is an enlarged perspective view of a pair of molds used in the sequential molding method according to the present invention.

FIG. 5 is a conceptual diagram showing a state of a sequential forming method according to the present invention.

FIG. 6 is a perspective view showing a state in which a sequential forming method according to the present invention is being performed.

FIG. 7 is a sectional view showing a state in which the sequential forming method according to the present invention is being performed.

FIG. 8 is a partially enlarged side view showing another embodiment of the processing head used in the sequential forming method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Articulated robot 2 Processing head 3 Frame 4 Guide device 5 Bracket 7 Hydraulic cylinder 8 Servo valve 12 Pressure head 13 Controller 14 Amplifier for pressure head 17 Servo amplifier 22 Channel setting unit 26 Pump unit 29 A pair of successive molding dies 29a Mold 29b Lower mold 29c-29h Molding surface 31 General-purpose positioning device 50, 51 Bracket 52 A pair of molding dies A 53 A pair of molding dies B

Claims (11)

[Claims] 1. A method for performing successive forming using a pair of forming dies relatively moving along a flange portion of a thin plate-shaped elasto-plastic body, wherein the forming of the thin plate-shaped elasto-plastic body is performed via the pair of forming dies. When a force for forming is applied to the processing target flange portion, at least a part of the both surfaces of the pair of forming dies is formed on the front surface of the flange portion before processing on the entrance side where the flange portion enters. At the exit side where the flange portion exits, at least a part of the flange portion comes into contact with a desired shape after processing, or any of the molding surfaces that bites by an amount of elastic recovery. Between the molding surface on the inlet side and the molding surface on the outlet side, the flange portion changes smoothly along a direction passing between the molding dies, and the molding die is While moving relatively along the A pair of molding dies having a continuous molding surface for sequentially deforming the flange portion from a shape before machining to a desired shape after machining while contacting the flange portion when a force required for molding is repeatedly applied to the flange portion During the forming, the processing target flange portion of the thin plate elasto-plastic body is passed from the inlet side to the outlet side, and at the same time, a forming process in which a vibration load generating device is generated in the flange portion via the pair of forming dies. Is repeatedly applied along the flange portion to sequentially accumulate minute plastic deformation, and the flange portion to be processed of the thin plate-shaped elasto-plastic body is sequentially changed from a shape before processing to a desired shape after processing. A sequential forming method of a thin plate-shaped elasto-plastic flange portion, characterized by forming. 2. A method according to claim 1, further comprising: applying a force necessary for causing plastic deformation for forming to a forming target flange portion of the thin plate-shaped elastoplastic body through the pair of forming dies; 2. The method according to claim 1, wherein when performing relative movement between the pair of forming dies and the thin elasto-plastic body, at least one of the pair of forming dies or the thin elasto-plastic body is automatically controlled. Sequential forming method of thin plate-shaped elastoplastic flange. 3. The method according to claim 2, wherein the movements of both the pair of forming dies and the thin elasto-plastic body are automatically and cooperatively controlled. 4. When automatically controlling the movement of at least one of the pair of forming dies and the thin plate-shaped elasto-plastic body, at least one of a relative position, a relative posture, and a relative speed is automatically controlled. 3. A method for sequentially forming a thin plate-shaped elastoplastic flange portion according to claim 2. 5. The apparatus according to claim 1, wherein the degree of freedom of relative movement between the pair of forming dies and the thin plate-shaped elasto-plastic body is 3 or more in position and 3 or more in posture, that is, 6 or more in total. A method for sequentially forming a thin plate-shaped elasto-plastic body flange portion according to the above. 6. In addition to the automatic control of the relative movement between the pair of forming dies and the sheet-shaped elasto-plastic body, in cooperation with the automatic control, a pair of forming dies are formed on the flange to be processed of the sheet-shaped elasto-plastic body. At least one of the magnitude of the force generated by the vibration load generating device that repeatedly applies a force for forming via the process, the cycle of repetition, and the relative moving speed between the pair of forming dies and the thin plate-shaped elastoplastic body 2. The method according to claim 1, wherein the step (c) is automatically controlled so as to change in accordance with a change in the processing content along the processing target flange. 7. A pair of forming dies for sequentially forming a flange portion while relatively moving along the flange portion of the thin plate-shaped elasto-plastic body, wherein the pair of forming dies are formed through the pair of forming dies. When a force for forming is applied to the processing target flange portion of the elasto-plastic body, both of the pair of forming dies are
At the entrance side where the flange portion enters, it has a molding surface at least partly in contact with the surface before processing of the flange portion, and at the exit side where the flange portion exits, after the machining of the flange portion It has a molding surface that at least partially touches the desired shape, or has an indentation by an amount of elastic recovery, and the flange portion is provided between the molding surface on the inlet side and the molding surface on the outlet side. When the force required for molding is repeatedly applied to the flange portion while changing relatively smoothly along the direction passing through the pair of molds while the mold relatively moves along the flange portion. Wherein a continuous molding surface is formed so as to sequentially deform the flange portion from a shape before machining to a desired shape after machining while being in contact with the flange portion. Thin plates according to 5 and 6 Incremental forming mold used in the forming method of the elasto-plastic body flange. 8. A vibration load which periodically fluctuates between a predetermined upper limit value and a lower limit value of a load at a predetermined period, and transmits the vibration load from a load transmitting portion of the apparatus to the outside. A device that allows the amplitude of the part to change depending on the load deformation characteristics of the object transmitting the vibration load,
The value of the vibration load generated by the device, the cycle thereof, the processing conditions of the amplitude of the load transmitting portion can be changed, and the direction opposite to the direction in which the load transmitting portion transmits the vibration load for the sequential forming process. 7. A displacement larger than a set range of an amplitude when transmitting a vibration load for sequential forming in a direction is provided.
A vibration load generator for use in the method for sequentially forming a thin plate-shaped elasto-plastic body flange portion described in the above. 9. An operating portion of a vibration load generating device having a load transmitting portion, one of a pair of forming dies, and a fixed side of a guide device for guiding relative movement of the pair of forming dies. 1
Attached to a frame body, the other of the pair of molds is attached to the movable part of the guide device, so that the pair of molds can be relatively moved on a locus required for processing by the guide device. The vibration load and the displacement are transmitted from the load transmitting portion of the vibration load generating device to the molding die attached to the movable side of the guide device. 6. A processing head used in the method for sequentially forming a thin plate-shaped elastoplastic flange portion according to 6. 10. The processing head according to claim 9, further comprising at least one pair of molding surfaces having different shapes from those described above.
7. A process used for a method of forming a thin plate-shaped elasto-plastic body flange portion according to claim 1, further comprising a forming die for a sequential forming process having the following requirements. head. 11. A thin plate-shaped elastoplastic flange characterized by further comprising at least one pair of forming dies for local single-shot forming other than forming dies for sequential forming, attached to the working head according to claim 9 or 10. Claim 1 and 2,
A processing head that can be used in combination with the sequential forming processing described in 3, 4, 5, and 6.