WO2024013950A1

WO2024013950A1 - Sequential shaping method and sequential shaping device

Info

Publication number: WO2024013950A1
Application number: PCT/JP2022/027753
Authority: WO
Inventors: 陽祐岡野; 紘敬三輪; 孝邦岩瀬; 秀徳渡辺
Original assignee: 日産自動車株式会社
Priority date: 2022-07-14
Filing date: 2022-07-14
Publication date: 2024-01-18

Abstract

Provided is a sequential shaping method for shaping a metal plate W, being held at the periphery thereof, into a three-dimensional shape by moving the tip-end part of a bar-shaped tool T pressed against the main surface of the metal plate W. As the bar-shaped tool T moves, the metal plate W is shaped while forming a machining trajectory Fw having an amplitude H in a direction intersecting the movement direction of the bar-shaped tool T and extending along the shaping surface of the metal plate W. In this way, the machined portion along which the bar-shaped tool T has passed can be made virtually wider and tool trace can be suppressed during shaping, thus enhancing the appearance quality of the shaped product, while achieving reductions in facility expenses and manufacturing costs.

Description

Sequential molding method and sequential molding device

The present invention relates to a sequential forming method and a sequential forming apparatus for forming a metal plate into a three-dimensional shape by pressing and moving a rod-shaped tool against the metal plate.

As a conventional sequential molding method, there is one described in Patent Document 1, for example. The sequential forming method described in Patent Document 1 uses a rod-shaped pressing member placed on one side of a plate material and a concave concave pressing member placed on the other side of the plate material. The rod-shaped pressing member includes a flexible member at its tip.

The above sequential forming method involves pressing the flexible member of the rod-shaped pressing member against the plate material, moving the rod-shaped pressing member while drawing contour lines, and shaping the plate material so as to spread it out within the concave pressing member to form a three-dimensional shape. . The above sequential forming method uses a rod-shaped pressing member having a flexible member to increase the contact area between the rod-shaped pressing member and the plate material, thereby suppressing tool marks.

Japanese Patent No. 3777130

However, in the conventional sequential forming method as described above, since a rod-shaped pressing member with a flexible member that contacts the plate material is used, sufficient deformation of the plate material is difficult to occur, and auxiliary equipment such as a concave pressing member is required. Not only is this necessary, but the life of the bar-shaped pressing member is short, so it is necessary to replace it frequently. As a result, in the conventional sequential molding method, although it is possible to suppress tool marks on the molded product, it is difficult to reduce equipment costs and manufacturing costs.

The present invention has been made in view of the above-mentioned conventional situation, and provides a sequential molding method and a sequential molding apparatus that can improve the appearance quality of molded products while reducing equipment costs and manufacturing costs. It is intended to.

The sequential forming method according to the present invention is a method of forming a metal plate into a three-dimensional shape by pressing and moving the tip of a rod-shaped tool against the main surface of a metal plate whose periphery is held. This sequential forming method is characterized by forming a metal plate while forming a machining trajectory that intersects with the direction of movement of the rod-shaped tool and has an amplitude in a direction along the forming surface of the metal plate as the bar-shaped tool moves. .

The sequential forming device according to the present invention is a sequential forming device used in the above-described sequential forming method, and includes a clamp device that holds the periphery of a metal plate, a bar-shaped tool placed on one side of the metal plate, and a bar-shaped tool that is connected to each other. It is equipped with a tool driving device that moves in three orthogonal axes directions, and a vibration applying device that applies vibration to at least one of the clamp device and the rod-shaped tool, and the metal plate is moved while forming a machining trajectory by the vibration applied by the vibration applying device. It is characterized by being moldable.

By adopting the above configuration, the sequential molding method and sequential molding apparatus according to the present invention do not require auxiliary equipment such as a mold, and use hard rod-shaped tools with a long life, reducing equipment costs and manufacturing costs. It is possible to improve the appearance quality of molded products while achieving a reduction in

FIG. 2 is an explanatory cross-sectional view showing an enlarged processing locus with regular amplitude in the first embodiment of the sequential forming method and sequential forming apparatus according to the present invention. FIG. 3 is a cross-sectional view showing the main parts of sequential molding. FIG. 3 is an explanatory diagram showing a machining trajectory with irregular amplitude. FIG. 3 is an explanatory diagram showing a machining locus with regular amplitudes in adjacent circumferential paths. FIG. 6 is an explanatory diagram showing a machining locus with irregular amplitude in adjacent circumferential paths. It is a graph showing the relationship between amplitude and surface roughness of a molded surface. It is a graph showing the relationship between the ratio of amplitude to the interval between adjacent circular paths and the displacement interval in the machining trajectory. It is a side view explaining the rod-shaped tool in 2nd Embodiment.

<First embodiment>
FIG. 1 is a diagram showing a sequential molding apparatus to which the sequential molding method according to the present invention can be applied. The illustrated sequential forming apparatus basically includes a clamp device 1 that holds the periphery of a metal plate W, a bar-shaped tool T disposed on one main surface side (upper side in FIG. 1) of the metal plate W, and a bar-shaped tool T. The tool drive device 2 includes a tool drive device 2 that drives the T, and a main control device 3 that controls the tool drive device 2.

The metal plate W is a flat plate that is a raw material for a molded product, and in this embodiment, the periphery is held in a horizontal state by the clamp 1. Note that the sequential molding method according to the present invention is dieless forming without using a mold. In this sequential forming method, it is also possible to hold the metal plate W in a vertical state or an inclined state, and the rod-shaped tool T and the clamp device 1 are arranged depending on the attitude of the metal plate W. The clamp device 1 includes a fixed lower frame portion 1A and an upper frame portion 1B that can be raised and lowered relative to the lower frame portion 1A, and a metal plate W is disposed between the lower frame portion 1A and the upper frame portion 1B. firmly clamp around the area.

In the illustrated example, the rod-shaped tool T is held in a posture with its axis in the vertical direction, and is a well-known tool whose lower tip has an appropriate shape such as a spherical shape, and is driven by the tool drive device 2 to drive three orthogonal axes. driven in the direction. This rod-shaped tool T is hard and has a long life, and is typically made of metal.

As the tool drive device 2, a multi-axis control type work robot, an NC machine tool, etc. can be used. The tool driving device 2 in the illustrated example moves the attached bar-shaped tool T in the X and Y directions, which are horizontal directions, and in the Z direction, which is vertical. Note that the rod-shaped tool T can also be rotated around each axis.

The main control device 3 is a computer, and as data for driving the rod-shaped tool T, all moving routes from the forming start point to the forming end point, the moving speed, the amount of pressure applied to the metal plate W, etc. are input in advance. It has been done.

Generally, in the sequential forming method, as shown in FIG. 1, the tip of a rod-shaped tool T is pressed against and moved against a metal plate W whose periphery is held by a clamp device 1. FIG. 2 is a sectional view of the bar-shaped tool T viewed from the moving direction. In FIG. 2, the rod-shaped tool T moves along the circumferential path at the position indicated by the solid line, and then moves toward the center of the metal plate W (to the right in FIG. 2) and downward, as indicated by the imaginary line in the figure. Then, repeat the movement along the next circular path and the pitch feeding operation. Thereby, in the sequential molding method, the metal plate W is molded so as to gradually push down the bottom part, and finally a three-dimensional shaped molded product is obtained.

In the sequential forming method according to the present invention, when performing sequential forming as described above, as the bar-shaped tool T moves, a direction perpendicular to the moving direction and along the forming surface of the metal plate W (in the direction of arrow A in the figure) ) The metal plate W is formed while forming a machining trajectory Fw having an amplitude of .

At this time, in the sequential forming method, as shown in the enlarged view in FIG. 1, the machining trajectory Fw has a regular amplitude with respect to the machining reference line SL, which is the center of movement of the rod-shaped tool T, or as shown in FIG. , it is possible to select a machining trajectory Fw whose amplitude is irregular with respect to the machining reference line SL.

The above machining trajectory Fw can be formed by inputting a program in advance to the main controller 3 as a movement path of the rod-shaped tool T, and controlling the tool driving device 2 with the program. In addition, as shown in FIG. 1, the machining trajectory Fw is determined by providing vibration imparting

devices

4 and 5 on at least one of the clamp device 1 and the tool drive device 2, and the metal plate W held by the clamp device 1 and the tool drive device. It can be formed by applying vibration to at least one of the rod-shaped tools T attached to the tool T.

Note that the illustrated machining trajectory Fw is a line through which the center of the rod-shaped tool T passes. In sequential forming, the rod-shaped tool T contacts the metal plate W over a predetermined area. Therefore, the machining portion (machining trajectory Fw) actually formed by the passage of the rod-shaped tool T has a constant width according to the contact area, as partially shown in the upper left of FIGS. 1 and 3. . That is, in the sequential forming method of this embodiment, the bar-shaped tool T is moved based on a program or the bar-shaped tool T and the metal plate W are vibrated relatively so that the actual machining trajectory Fw can be obtained. .

In the above sequential forming method, as shown in FIG. 4, when the machining trajectory Fw has a regular amplitude, in a preferred embodiment, the movement path of the bar-shaped tool T includes a contour line-shaped circumferential path, and the machining trajectory The amplitude of Fw is H (mm), the interval between adjacent circumferential paths is Ps (mm), the radius of curvature of the tip of the bar tool is R (mm), and the main surface of the metal plate W before forming and the slope after forming. The amplitude H of the machining trajectory Fw satisfies 2H≧1.2Ps−R*θ, and the forming angle that is the angle formed by is θ (shown in FIG. 2). It is possible to employ a configuration in which the distance G satisfies G≦0.25/H (mm), and more preferably, the interval G satisfies G≦0.225/H (mm). Note that the constant 1.2 in the formula for the amplitude H was calculated based on the conditions that led to a pass determination in the test described later.

In addition, in the above sequential forming method, as shown in FIG. 5, when the machining trajectory Fw is irregular in amplitude, as a preferred embodiment, the movement path of the rod-shaped tool T includes a contour line-shaped circumferential path, The amplitude of the machining trajectory Fw is H (mm), the interval between adjacent circumferential paths is Ps (mm), the radius of curvature of the tip of the bar tool T is R (mm), the main surface of the metal plate W before forming and after forming. The forming angle, which is the angle formed with the slope of It is possible to adopt a configuration in which the interval G for displacement satisfies G≦0.25/H (mm), and more preferably, the interval G satisfies G≦0.225/H (mm).

The above sequential molding method was tested. In the test, forming was performed at a forming angle θ of 15 degrees using an aluminum plate (metal plate W) with a thickness of 0.95 mm and a rod-shaped tool T with a diameter of 20 mm and a radius of curvature R at the tip of 3 mm. . In this case, in both cases where the amplitude H is regular and irregular, the interval Ps of the circumferential path is kept constant at 1,159 mm, and the interval that is displaced with the amplitude H in the machining path Fw (displacement interval) G was kept constant at 0.5 mm.

Then, successive molding was performed while changing the amplitude H in 100 (μm) increments between 100 (μm) and 500 (μm), and the surface roughness (arithmetic mean roughness) Ra of the molded surface was measured. As a result, when forming is performed sequentially while forming the machining trajectory Fw, the width of the machining part becomes pseudo-wider than when the bar-shaped tool T is moved linearly, and the tool marks become less noticeable. As shown in FIG. 6, it was found that as the amplitude H increases, the surface roughness Ra of the molding surface decreases, making it possible to significantly suppress tool marks.

In addition, in the above test, as mentioned above, the interval Ps of the circular path and the displacement interval G of the machining path Fw were constant at 0.5 mm, and the amplitude H was 30 (μm), 150 (μm), 300 (μm), 400 (μm) and successive molding was performed.

As a result, as shown in Fig. 7, when the amplitude H was set to 300 (μm) and 400 (μm) (triangles in the figure) was better than when the amplitude H was set to 30 (μm) and 150 (μm) (triangles in the figure). It was found that the tool mark (circle) in the figure had a more remarkable effect of suppressing tool marks. Note that FIG. 7 shows the relationship between the ratio of the amplitude H to the pitch Ps of the circumferential path and the displacement interval G.

In the above sequential forming method, according to the above test results, the interval G that is displaced with the amplitude H in the machining trajectory Fw satisfies G≦0.25/H (mm), and more preferably G≦0.225. It has been found that by satisfying /H (mm), a good molding surface with hardly visible tool marks can be obtained.

In the sequential forming method described in the above embodiment, as the bar-shaped tool T moves, the metal sheet is Form W. As a result, the sequential forming method described above does not require auxiliary equipment such as molds, and uses a long-life hard rod-shaped tool T, reducing equipment and manufacturing costs while eliminating tool marks. The appearance quality of the molded product can be improved by molding a molded surface that is difficult to see.

The sequential forming apparatus described in the above embodiment includes a clamp device 1, a rod-shaped tool T, a tool drive device 2, and

vibration applying devices

4 and 5 that apply vibration to at least one of the metal plate W and the rod-shaped tool T. We are prepared. Then, the metal plate W is formed while forming a machining trajectory Fw by the vibrations applied by the

vibration applying devices

4 and 5. Alternatively, the tool drive device 2 moves the bar-shaped tool T along a movement path that forms a processing trajectory Fw to form the metal plate W.

As a result, the sequential forming device does not require auxiliary equipment such as molds, uses a long-life hard rod-shaped tool T, reduces equipment costs and manufacturing costs, and makes it difficult to see tool marks. The molding surface can be molded to improve the appearance quality of the molded product.

In addition, in the above sequential forming method, the amplitude H of the machining trajectory Fw satisfies 2H≧1.2Ps−R*θ, and the interval G of displacement with the amplitude H in the machining trajectory Fw is G≦0.25/H ( mm), it is possible to enhance the effect of suppressing tool marks when the machining trajectory Fw has a regular amplitude H. Furthermore, the above sequential forming method has the effect of suppressing tool marks when the machining trajectory Fw has a regular amplitude H by making the interval G satisfy G≦0.225/H (mm). It is possible to realize further improvements in

Furthermore, in the above sequential forming method, the amplitude H of the machining trajectory Fw is a random value less than or equal to Hmax satisfying 2H≧1.2Ps−R*θ, and the interval G of displacement with the amplitude H in the machining trajectory Fw is By satisfying G≦0.25/H (mm), the effect of suppressing tool marks can be enhanced even when the machining trajectory Fw has an irregular amplitude H. Furthermore, the above sequential forming method suppresses tool marks when the machining trajectory Fw has an irregular amplitude H by making the interval G satisfy G≦0.225/H (mm). Further improvement in effectiveness can be achieved.

<Second embodiment>
FIG. 8 is a diagram showing a rod-shaped tool T of the second embodiment of the sequential forming method and sequential forming apparatus according to the present invention. The sequential forming device, similar to the one shown in FIG. 1, includes a clamp device (1) that holds the periphery of the metal plate (W), a bar-shaped tool T placed on one side of the metal plate (W), and a bar-shaped tool T. The tool drive device (2) moves the bar-shaped tool T in three axial directions orthogonal to each other, and the tool drive device (2) holds the bar-shaped tool T rotatably around its axis. The rod-shaped tool T of this embodiment has a wave-shaped protrusion 10 that forms a machining trajectory Fw around the entire circumference of the tip.

In the first embodiment described above, the metal plate (W) is machined while forming a machining trajectory (Fw) having an amplitude (H) by moving the bar-shaped tool T that is programmed in advance or by applying vibration to the bar-shaped tool T. to form. On the other hand, when the bar-shaped tool T of this embodiment is used, by pressing the bar-shaped tool T against the metal plate (W) and moving it while rotating around the axis, the protrusion 10 allows the machining trajectory to be The metal plate (W) is formed while forming (Fw).

In the sequential forming method and sequential forming apparatus using the above-mentioned bar-shaped tool T, as in the first embodiment, the width of the machining portion (machining trajectory) through which the bar-shaped tool T actually passes becomes thicker in a pseudo manner, and the tool marks are It is possible to obtain a good appearance quality in which the ridges are not noticeable, and in particular, it is possible to form a machining locus with an amplitude by the protrusion 10 of the bar-shaped tool T, which simplifies the device structure and further reduces equipment costs and manufacturing costs. can contribute to

The structure of the sequential molding method and sequential molding apparatus according to the present invention is not limited to the above embodiments, and can be modified as appropriate without departing from the gist of the present invention.

Fw Machining trajectory H Amplitude T Bar-shaped tool W Metal plate 1 Clamp device 2

Tool drive device

4, 5 Vibration imparting device 10 Projection portion

Claims

In a sequential forming method of forming the metal plate into a three-dimensional shape by pressing and moving the tip of a bar-shaped tool against the main surface of the metal plate whose periphery is held,
A sequential forming method characterized in that, as the bar-shaped tool moves, the metal plate is formed while forming a machining locus that intersects the direction of movement of the bar-shaped tool and has an amplitude in a direction along the forming surface of the metal plate.
The movement path of the rod-shaped tool includes a contour line-shaped circular path,
The amplitude of the processing trajectory is H (mm), the interval between adjacent circumferential paths is Ps (mm), the radius of curvature of the tip of the rod-shaped tool is R (mm), the main surface of the metal plate before forming and after forming. The forming angle which is the angle formed with the slope of is θ,
The amplitude H of the machining trajectory satisfies 2H≧1.2Ps−R*θ,
2. The sequential forming method according to claim 1, wherein an interval G that is displaced with the amplitude in the machining trajectory satisfies G≦0.25/H (mm).
The movement path of the rod-shaped tool includes a contour line-shaped circular path,
The amplitude of the processing trajectory is H (mm), the interval between adjacent circumferential paths is Ps (mm), the radius of curvature of the tip of the rod-shaped tool is R (mm), the main surface of the metal plate before forming and after forming. The forming angle which is the angle formed with the slope of is θ,
The amplitude H of the machining trajectory is a random value less than or equal to Hmax that satisfies 2H≧1.2Ps−R*θ,
2. The sequential forming method according to claim 1, wherein an interval G of displacement with the amplitude in the machining trajectory satisfies G≦0.25/H (mm).
The sequential forming method according to claim 2 or 3, wherein the interval G satisfies G≦0.225/H (mm).
A sequential molding device used in the sequential molding method according to claim 1,
a clamp device that holds the periphery of the metal plate; a rod-shaped tool disposed on one side of the metal plate; a tool drive device that moves the rod-shaped tool in three axes orthogonal to each other; A vibration applying device that applies vibration to at least one of the tools,
A sequential forming apparatus characterized in that the metal plate is formed while forming the machining locus using vibrations applied by the vibration applying device.
A sequential molding device used in the sequential molding method according to claim 1,
comprising a clamp device that holds the periphery of the metal plate, the rod-shaped tool disposed on one side of the metal plate, and a tool drive device that moves the rod-shaped tool in three axial directions orthogonal to each other,
A sequential forming apparatus characterized in that the tool driving device moves the rod-shaped tool along a movement path that forms the machining trajectory.
A sequential molding device used in the sequential molding method according to claim 1,
comprising a clamp device that holds the periphery of the metal plate, the rod-shaped tool disposed on one side of the metal plate, and a tool drive device that moves the rod-shaped tool in three axial directions orthogonal to each other,
The tool driving device holds the rod-shaped tool rotatably about its axis, and the rod-shaped tool has a protrusion portion that forms the machining trajectory around the entire circumference of the tip portion. Sequential molding equipment.