JPH0957381A - Metallic thin sheet formed product and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metallic thin sheet formed product, such as a door of a control box or refrigerator, having large outer diameter and high side wall height by using the metallic thin sheet and to provide a manufacturing method thereof. SOLUTION: A straight line side wall 13 is bent at a set angle to a reference surface 12 and successively, a corner part 14 to be curved side part 15 left between the adjacent straight line side walls 13 is formed with a successive forming method to manufacture the metallic thin sheet formed product. The bending work and a drawing work are combined and then, the box-shaped metallic thin sheet having large outer diameter size and comparatively deep depth can be manufactured in a short time at a low cost without impairing the treatment performance of the surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a box-shaped metal thin plate molded product such as a control box or a refrigerator door which has a large outer diameter and a high side wall height and uses a thin metal plate. Is.

[0002]

2. Description of the Related Art In prior art 1, a control box or a door of a refrigerator is made of a thin iron plate having a thickness of 2.3 mm or less, for example. It was made by drawing using an expensive wear-resistant mold. Further, as the prior art 2, Japanese Patent Laid-Open No.
In Japanese Patent Publication No. 154828, when a straight portion is V-bent, a die and a punch having a specific shape are used to gradually loosen the degree of bending as it approaches both corners, and then the corners are incompletely bent. It is known that a metal product having arc-shaped portions at both corners is manufactured by separately drawing each of the metal sheets using a small press machine. In addition, as conventional technology 3, a collection of lectures (1
993) page 615, there is described an example of research on the spinning method of a non-rotating body.

[0003]

In the case of the above-mentioned prior art 1, if the size of the product changes even a little, the mold cannot be used and another expensive mold is required. Had. Further, even if the above-mentioned conventional technique 2 is applied to the production of a thin metal plate product such as a control box or a refrigerator door having a large outer diameter dimension and a high sidewall height dimension, the shape of the corner portion remaining after bending becomes complicated. Therefore, there is a problem that it is difficult to remove wrinkles by drawing using a small press machine. Further, even if the above-mentioned prior art 3 is applied to the manufacture of a thin metal plate product such as a control box or a door of a refrigerator having a large outer diameter dimension and a high sidewall height dimension, if it is started from the flat plate state, the processed surface It is necessary to scan the entire surface many times with a small tool, which requires an extremely large number of man-hours (time). In addition, when the area is large and the plate thickness is thin, there is no rigidity in the flat plate state, and a small tool partially However, even if the tool is deformed, the tool returns when the small tool is moved to the next point, and the molding does not proceed easily, which makes the molding difficult.

In order to solve the above-mentioned problems of the prior art, an object of the present invention is to provide a control box which has an excellent appearance with no wrinkles and which is inexpensive and has a large outer diameter and a high sidewall height. It is to provide a box-shaped thin metal plate product such as a door of a refrigerator. Another object of the present invention is to use a thin surface-treated steel sheet as a raw material, which has an excellent appearance without wrinkles and the like, and is inexpensive and has a large outer diameter dimension and a high side wall height dimension. It is to provide molded products. Another object of the present invention is not to use an expensive mold, to require a large number of steps, and to have an excellent appearance without wrinkles or the like. It is an object of the present invention to provide a method for manufacturing a metal thin plate molded product, which is capable of manufacturing a metal thin plate molded product having a large size. Another object of the present invention is to use a thin metal plate having a thickness of 2.3 mm or less as a material, without using an expensive mold, and without requiring a lot of man-hours, and having an excellent appearance without wrinkles or the like. It is an object of the present invention to provide a method for manufacturing a metal thin plate molded product, which has a large outer diameter and a high side wall height, and which can be manufactured. Another object of the present invention is to provide a method for manufacturing a metal thin plate molded product having a significantly improved followability even if the size of the metal thin plate molded product having a large outer diameter dimension and a high sidewall height dimension changes. It is in. Another object of the present invention is to
It is an object of the present invention to provide a method for manufacturing a metal thin plate molded product, which can be applied to a product made of a surface-treated steel plate of a thin plate without any trouble.

[0005]

In order to achieve the above object, the present invention is directed to a plurality of straight part side walls bent at a desired angle with respect to a front plate part of a thin metal plate, and between the straight part side walls. And a corner portion formed by sequentially forming the curved side portion of the metal thin plate molded article. Further, the present invention is characterized in that, in the metal thin plate molded product, the metal thin plate is formed to have a thickness of 1.5 mm or less.
Further, the present invention is characterized in that, in the metal thin plate molded product, the depth of the side wall of the straight portion is about 1 cm to 8 cm. Further, the present invention is characterized in that, in the metal thin plate molded product, the metal thin plate is a surface-treated steel plate.
Further, the present invention provides four corners formed by sequentially molding the straight side wall of four sides bent at a desired angle with respect to the front plate portion of the thin metal plate and the curved side portion between these straight side walls. And a metal thin plate molded product. Further, the present invention is characterized in that the thin metal plate molded product is a control box for housing electrical products. Further, the present invention is characterized in that the thin metal plate product is a refrigerator door.

The present invention also provides a preparatory step for preparing a material for a thin metal plate, and a bending process for bending the raw material for the thin metal plate prepared in the preparatory step at a desired angle with respect to a reference surface of a straight portion side wall. A metal thin plate molded article, characterized by comprising a step and a sequential forming step of forming a corner portion left between the linear side walls processed in the linear part side wall bending step by a sequential forming method. It is a manufacturing method. The present invention also provides a preparatory step of preparing a raw material for a metal thin plate, and a raw material for the metal thin plate prepared in the preparatory step,
Between the bending process for bending the straight side walls at a desired angle with respect to the reference plane so that the waist does not bend at the corners between the straight side walls, and between the straight side walls processed in the bending process. And a step of sequentially forming the remaining corners by a successive forming method. The present invention also provides a preparatory step of preparing a raw material for a metal thin plate, and the raw material of the metal thin plate prepared in the preparatory step, in which the straight portion side wall is used as a reference plane so as not to cause bending at the corner portion between the straight portion side walls. On the other hand, a bending process for performing a bending process at a desired angle and a corner portion left between the side wall of the straight part processed in the bending process are used to form a desired locus of movement of the forming tool from the outside based on NC control. The method for producing a metal thin plate molded product, comprising:

Further, according to the present invention, in the preparatory step for preparing the material for the metal thin plate, and for the material for the metal thin plate prepared in the preparatory step, the side wall of the straight part is formed so that the corner portion between the side wall of the straight part is not bent. For a forming tool having a rotatable member at its tip at a bending step of performing bending at a desired angle with respect to the reference plane, and a corner portion left between the side wall of the straight portion processed by the bending step.
And a step of sequentially forming the corner portion from the outside by a successive forming method so as to obtain a desired movement trajectory based on C control, and a method for manufacturing a thin metal sheet product. The present invention also provides a preparatory step of preparing a raw material for a metal thin plate, and the raw material of the metal thin plate prepared in the preparatory step, in which the straight portion side wall is used as a reference plane so as not to cause bending at the corner portion between the straight portion side walls. On the other hand, the bending step for bending at a desired angle and the corner portion left between the side wall of the straight portion processed in the bending step are provided from the outside based on the partial mold installed inside and NC control. And a desired forming path of the forming tool, and a successive forming step of forming by a successive forming method.

Further, according to the present invention, in the preparatory step of preparing the raw material of the metal thin plate, and in the raw material of the metal thin plate prepared in the preparatory step, the side wall of the straight portion is prevented so that the corner portion between the side wall of the straight portion is not bent. A bending step in which a bending process is performed at a desired angle with respect to the reference plane, and a corner portion left between the linear part side walls processed in the bending step,
Sequential forming process for forming by a sequential forming method using a partial mold installed on the inside and a desired movement trajectory and a desired movement trajectory in the depth direction that match the contours of the corners of the molding tool from the outside based on NC control And a step of manufacturing a thin metal plate molded article.

Further, according to the present invention, in the method for manufacturing a thin metal plate product, the side wall of the straight line portion is bent in the bending step to increase the rigidity of the corner portion, thereby enabling the successive forming in the step of sequentially forming. It is characterized by that. Further, the present invention is characterized in that, in the method for manufacturing a molded product of a metal thin plate, a material of the metal thin plate prepared in the preparing step is a surface-treated steel plate. Further, the present invention is, in the method for producing a metal thin plate molded article, the sequential forming method in the sequential forming step,
It is characterized by the contour pushing method. Further, the present invention is characterized in that, in the method for producing a thin metal plate product, the sequential forming method in the sequential forming step is a multistage drawing method. Further, the present invention is characterized in that, in the method for producing a metal thin plate molded article, the sequential forming method in the sequential forming step is a spinning method. Further, in the present invention, in the method for manufacturing a metal thin plate molded product, in the material of the metal thin plate prepared in the preparation step, the side wall height dimension of the corner portion is substantially equal to the straight line side wall height dimension after the successive molding. The development area is set so that

Further, according to the present invention, the corner portion which is to be a curved side portion left between the straight portion side wall and the straight portion side wall is bent at a set angle with respect to the straight portion side wall and the reference surface. Metal thin plate molded product formed by the sequential molding method and its processing method,
Even if it is a box-shaped product with a relatively large outer dimension and depth, such as a control box for storing electrical items, a door of a refrigerator, etc., it has an excellent appearance without using a large and expensive mold and equipment. The metal thin plate molded product can be obtained.

Further, in the present invention, specifically, the side wall of the straight portion is bent at a set angle with respect to the reference plane, and then the curved side portion left between the side wall of the straight portion is formed. The corner portion to be formed is formed by the sequential forming method, and the sequential forming tool is moved in accordance with the contour of the curved portion forming the envelope, and the tool is moved downward or upward in the depth direction. It is a thing. That is, the moving range of the sequential forming tool, which requires a long time for processing, is set to be near a corner portion which is a curved side portion, and the other is a press or bender bending. As a result, the corner portion becomes a curved surface due to the influence of the bent portion, and wrinkles are much less likely to occur as compared with sequential forming from a metal thin plate material, and the wrinkle generation portion is limited to the vicinity of this corner portion. Since the area will be increased and the relative plate thickness will increase, prepare a simple partial mold (lower mold) for this part only,
It is characterized in that it is configured to suppress the occurrence of wrinkles. Further, since the side wall of the straight portion may be bent by using a bender or the like, it is not necessary to warp the side wall of the straight portion due to the die like drawing, and the side wall is combined with other parts. The time can be easily designed.

[0012]

With the above structure, a box-shaped thin metal sheet product having a good appearance without wrinkles and having a large outer diameter and a small outer diameter and a high sidewall height, such as a control box or a door of a refrigerator. Can be realized. In addition, with the above configuration, a box-shaped thin metal sheet product that has a large outer diameter dimension and a high side wall height dimension, has an excellent appearance that does not cause wrinkles, etc., using a thin surface-treated steel sheet as a raw material. can do. Further, with the above structure, the rigidity of the corner portion is enhanced by bending the side wall of the straight portion in the bending step, thereby enabling the sequential forming in the sequential forming step,
As a result, a metal thin plate molded product having a large outer diameter dimension and a high sidewall height dimension, which does not use an expensive die, does not require a large number of steps, and has an excellent appearance without wrinkles or the like. Can be manufactured. Further, with the above-described structure, the rigidity of the corner portion is increased by bending the side wall of the straight portion in the bending step, and the successive forming in the successive forming step is enabled. As a result, 2.3
A metal thin plate having a thickness of 1.5 mm or less (a plate thickness of 1.5 mm or less, particularly
4 to 0.6 mm) as a material, without using an expensive mold, and without requiring a lot of man-hours, and having an excellent appearance without wrinkles and the like, having a large outer diameter dimension and a side wall. It is possible to manufacture a metal thin plate molded product having a high height dimension.

Further, according to the above construction, by bending the side wall of the straight portion in the bending process, the rigidity of the corner portion is increased to enable the successive forming in the successive forming process. As a result, the outer diameter is large and the side wall is large. Even if the dimensions of a metal thin plate molded product having a high height change, the followability can be remarkably improved. Further, with the above-mentioned configuration, the rigidity of the corner portion is enhanced by bending the side wall of the straight part in the bending step, and the successive forming in the successive forming step is enabled, and as a result, a thin surface-treated steel sheet is used as the material. It can also be applied to Further, according to the above-mentioned configuration, since the reference surface occupying most of the blank shape of the thin plate molded product and the side wall of the straight portion are processed by the bending mold, that portion can be processed at a high processing speed such as a press or a bender, which is necessary for the processing. The time can be greatly shortened.

Further, according to the above construction, as the bending die used in the bending step, a commercially available standard die whose bending ridge line length can be variously changed by combination can be used, and if necessary, bending parts are produced in a unit of one piece. An automatic bending device is also commercially available, so it can be used. Further, with the above configuration, the remaining corner portion has a curved surface that is less likely to cause wrinkles during successive processing and has a small area. Therefore, the operating range of the sequential molding device for molding the curved side portion is the curved side portion plus the straight line portion. It is limited to the place where it takes a little on the side wall, and as a result, the mold and molding equipment used for this corner part is of course downsized,
It is not necessary to increase the number of passes for processing to prevent wrinkles, the processing range is small, and the relative plate thickness is increased. Therefore, it is possible to greatly reduce the processing fraction.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a case where a thin metal plate (about 2.3 mm or less) such as a thin iron plate which is a surface-treated steel plate is used and has a large outer dimension (about 30 cm to 300 cm) and a high sidewall height (about 30 cm). It is a perspective view showing a box-shaped metal plate molded product such as a control box or a door of a refrigerator used for housing electrical products. FIG. 2 is a view showing a flow chart showing a schematic process for producing the metal thin plate molded product shown in FIG. FIG. 3 is a development view showing a material of a thin metal plate prepared when the metal plate molded product 1 is formed. FIG.
(A) (b) is a figure which shows the method of forming a linear part side wall by bending with respect to the raw material of a thin metal plate. FIG.
(A) is a straight line (A,
FIG. 5B is a cross-sectional view taken along the line AA of the corner portion of FIG. 5A, showing a state in which the side walls of the broken lines B, C, and D) are bent. FIG. 6 is a diagram showing a method of successively forming the corner portions which should be the curved side portions left between the straight side wall portions of FIG. FIG. 7 is a view showing a contour pressing method which is a concrete processing method among the methods for successively forming the corners shown in FIG. 6, and FIG. 7A shows a state where the corners are formed when viewed from above the reference plane. The top view shown, (b) shows the 1st Example of pushing down of a rod-shaped tool, (a) AA arrow line view, (c) (a) BB arrow line view, (d). FIG. 7A is a view taken along the line AA of FIG. 8A showing a second embodiment of pushing down a rod-shaped tool. FIG. 8 is a diagram showing a method of sequentially forming a corner portion by a multistage drawing method different from that of FIG. 7. FIG.
(A) and (b) are figures which show the method of forming a corner part one by one by the spinning system different from FIG. 7, FIG. FIG.
FIG. 6 is a diagram showing an embodiment different from FIG. 5, showing a case where an area of a corner portion which is a curved side portion is reserved extra during blanking.

First, the metal thin plate molded product 1 will be described with reference to FIG. 1 is a box-shaped thin metal plate product. The box-shaped metal thin plate molded product 1 is, for example, a thin iron plate (printed steel plate (painted steel plate) or plated steel plate) having a thickness of about 2.3 mm or less (a thickness of about 2.3 mm or less is referred to as a thin plate). Such as a control box or a refrigerator door for storing electric products and the like, which are formed by molding a surface-treated steel sheet such as the above) into a box-like appearance. This metal thin plate molded product 1 has a plate thickness of about 0.4 to
A surface-treated steel plate such as a printed steel plate or a plated steel plate is used to make the external appearance for sale with a thickness of 1.5 mm. In the case of a control box, the size of the metal thin plate molded product 1 is, for example, 50 cm in length and 30 c in width.
m, depth of about 3 to 5 cm (thin plate having a thickness of about 0.4 to 0.6 mm), as a large one, for example, 200 cm in length and 10 in width.
It is made to have a depth of 0 cm and a depth of 3 to 5 cm (a thin plate having a thickness of about 1 to 1.5 mm). In addition, the size of the thin metal plate product 1 is
In the case of a refrigerator door, for example, 150 cm long, 50 cm wide,
It is made to a depth of about 2 to 4 cm (a thin plate having a plate thickness of about 0.4 to 0.6 mm). That is, since the metal thin plate molded product 1 is a control box for storing electric products such as a motor or a door of a refrigerator, a metal thin plate (about 2.3 mm or less (about 0.4 to
(1.5 mm) printed steel sheet or surface-treated steel sheet such as plated steel sheet) and has a large external dimension (about 3 mm).
0 cm to 300 cm), high sidewall height (approx. 1 cm)
It is a molded product. Reference numeral 12 forms the front plate of the metal thin plate molded product 1 and serves as a reference surface during manufacturing, and is therefore referred to as a reference surface in the present invention. 13 is, for example, 2.
Reference numeral 12 denotes a straight side wall formed by bending a thin iron plate of about 3 mm or less from the reference surface 12, and reference numeral 14 denotes a corner portion having a curved side portion 15 sandwiched between the straight side walls 13 and 13.

Next, a method for manufacturing the above-mentioned thin metal plate product 1 will be described with reference to FIGS. First, in a thin metal plate material (developed view) preparation step 21 shown in FIG. 2, a thin metal plate material (for example, a developed view shown in FIG. 3) 11 is prepared. In FIG. 3, the part indicated by the solid line is a development view when the above-mentioned metal thin plate molded product 1 is manufactured by the processing method of the present invention.
In particular, the P portion that hits the corner is obliquely cut with a precalculated size. By doing so, it is possible to eliminate the need for trimming the end face of the curved side portion 15 of the corner portion 14 after the completion of molding so as to be fitted to the other side wall 13 of the straight portion. That is, the trimming process 24 of the end face shown in FIG. 2 can be omitted. Broken line (A) (B)
(C) and (D) show bending lines of the straight part side wall 13 formed by bending at a set angle with reference to the reference surface 12. Broken lines (E), (F), (G), and (H) indicate molding lines of the corner portion 14.

Next, in a step 22 of bending the side wall of the straight portion shown in FIG. 2, a bending line (FIG. 4) is applied to the material 11 of the thin metal plate prepared as shown in FIG. Is indicated by a broken line) (A) (B)
(C) and (D) are bent at a set angle using a press (including a bender, etc.) or the like so that the curved side portion 15 does not bend at the waist, and the linear portion side wall 13 shown in FIG. 5 is made. At this stage,
The corner portion 14 that abuts the curved side portion 15 is not yet formed, and as shown in FIG. 5A, a concave ridge line (upper surface direction (reference surface 2
It becomes a concave ridgeline when viewed from above). ) (K) (L)
(M) and (N) are diagonal lines of about 45 degrees from the end points of the broken lines (A), (B), (C), and (D), and can be formed at the end 13a of the straight part side wall 13 near the center. In addition, a gentle convex ridgeline (as shown in FIG. 5B, in the upper surface direction (above the reference plane 12)
It becomes a convex ridgeline when viewed from above. ) (P) (Q) (R)
(S) can also be formed at the center of 15. These shapes may be somewhat irregular because they can be corrected at the time of successive molding as long as there is no waist bending at the curved side portion 15.
In this way, since the linear portion side wall 13 is formed by bending, even if the material 11 is a thin iron plate (thickness of about 0.4 to 0.6 mm) of 2.3 mm or less, for example, FIG. As shown in FIG. 5, the bent side portion 15 can be molded without wrinkles except for the corner portion 14 so that waist bending does not occur. Further, since the linear portion side wall 13 is formed by bending, even if the material 11 is a thin iron plate having a thickness of 2.3 mm or less (thickness of about 0.4 to 0.6 mm), the corner portion 1
It is possible to increase the rigidity of No. 4 and to enable the later-described sequential molding in the curved side portion 15.

In FIG. 4, the bending lines (A), (B), (C) and (D) are bent from the material 11 of the thin metal plate to form the straight side wall 1.
A specific bending method for forming 3 will be described. Reference numeral 41 is an upper die (male type) for bending the linear portion side wall 13 of the material 11 of the thin metal plate, and 42 is the linear portion side wall 1 of the material 11 of the thin metal plate.
A lower die (female die) for bending 3 is a plate retainer for retaining the reference surface 12 of the material 11 of the thin metal plate. Reference numeral 44 is a rubber piece for preventing the waist from breaking, and is attached to the side surface of the lower mold 42.
The length of the upper mold 41 and the lower mold 42 is the bending line (A).
A value slightly smaller than the lengths of (B), (C), and (D) is taken, and a rubber piece 44 for preventing waist bending is attached to the side surface. The reference surface 12 of the material 11 of the thin metal plate is suppressed by the plate retainer 43, and the minimum upper die 41 where the linear portion side wall 13 is bent is lowered to bend the linear portion side wall 13. As shown in the side view of FIG. 4B, the rubber piece 44 for preventing the waist from breaking is prevented by a, so that the bending ridgeline of the straight side wall 13 is prevented from reaching the bent side deformed portion 15 '. . Although FIG. 4 shows the case where the ironing bending die is used, a V bending die or a folding die may be used, but it is necessary to devise so that the waist is not bent.

Next, in the step 23 of sequentially forming each corner portion shown in FIG. 2, the linear side wall 13 is formed by bending as shown in FIG. A rod-shaped tool 1 that is attached and NC controlled
7 and the partial mold 16 made to match the corner shape to be the curved side portion 15 are successively molded to form the curved side portion 15 to complete the metal thin plate molded product 1 shown in FIG. Although the side wall 13 of the straight portion is formed by bending, the reference surface 12 is clamped to the partial mold 16. The partial mold 16 is made in conformity with the corner shape that becomes the curved side portion 15 described above. The rod-shaped tool 17 is attached to the main shaft of an apparatus that is NC-controlled similarly to the NC milling machine, and moves the corner portion 14 along the contour of the partial die 16 based on NC control to successively form it. . A roller 18 is attached to the tip of the rod-shaped tool 17 as shown in FIG. 6, so that the surface-treated steel plate, which is a thin metal plate, is not scratched, and the corner portions of the thin metal plate are sequentially and efficiently processed. It is configured so that the thin metal plate molded product 1 can be manufactured by molding. Needless to say, the roller 18 may be a rotating ball or the like.

Next, when the end face trimming step 24 shown in FIG. 2 is required (for example, when a material surplus is generated as the material 11 of the thin metal plate as shown in FIG. 10), the curved side The end face of the portion 15 is trimmed (cut) and removed to complete the thin metal plate product 1 shown in FIG.

Next, the successive forming method in each corner successive forming step 23 will be specifically described with reference to FIGS. First, of the successive forming methods, the contour pressing method will be described with reference to FIG. 12 is a straight part side wall 13
It is a reference surface of what was formed by bending. Fifteen
Is the curved side of the corner of the straight side wall 13 formed by bending. Reference numeral 16 is a partial mold made in conformity with the corner shape which becomes the curved side portion 15. Compared to the one obtained by bending the straight side wall 13 by a bending process as shown in FIG.
It is installed as shown in (a) and (c). The reference plane 1
2 is clamped to the partial mold 16 by a clamp member (not shown). A rod-shaped tool 17 having a rotary ball 19 attached to its tip is attached to a main shaft of an apparatus having an NC controlled configuration similar to an NC milling machine. Therefore, the rod-shaped tool 17 is controlled by NC control of the main spindle, following the partial mold 16 as shown by an arrow T, to a position slightly outside the ridgelines K, K as shown in FIG. 7A. Also in the depth direction, movement control is performed so as to move more than the depth of the linear portion side wall 13. These NC control data are
It is created based on CAD information such as design information of the thin metal plate product 1. Naturally, the shape of the rod-shaped tool 17 and the partial mold 16
It is necessary to create the NC control data in consideration of the shape and the like. Then, the pushing-down dimension of the rod-shaped tool 17 once is set to about 0.8 mm.

In this contour pushing-down method, the molding is completed by controlling the movement of the rod-shaped tool 17 as shown by the arrow T using the material remainder at the corners and continuing to feed only in the vertical direction as shown by the arrow V. Is. As the control of the pressing amount of the rod-shaped tool 17 in the contour pressing method, when pressing down flat along the contour line (T ₁ − as shown in FIG. 7B).
In _{T 2, T 3 -T 4,} T 5 -T 6, T 7 -T 8 and contours, depressing from T ₂ to T _3, from T ₄ to T _5, from T ₆ to T _7. ) And the curved surface (convex shape) of the ridgeline P in the curved side portion 5 is pressed down so that the deformation amount becomes equal (as shown in FIG. 7D, the ridgeline P has a convex shape). Therefore, the pushing amount is changed in accordance with this convex shape, that is, the pushing amount is lowered as it approaches the ridge line P between T ₃ and T ₄ , between T ₅ and T _6, and between T ₇ and T _8. Reduce the amount.) And so on. It is preferable that the control of the pressing amount of the rod-shaped tool 17 is changed depending on how easily wrinkles are generated, and an appropriate one is selected. In any case, by performing NC control of the spindle attached with the rod-shaped tool 17, it is possible to realize the successive forming by the contour pushing down method.

If there is a surplus of material after molding, it is natural to cut the surplus dimension at that time, but it is also possible to set so that there is no surplus. (For example, as shown in FIG. 3, it may be formed so that there is no material residue as the material 11 of the thin metal plate.) Next, of the successive forming method, the multistage drawing method will be described with reference to FIG. To do. In this multistage drawing method, the rod-shaped tool 7 is first drawn from the radius of the corner portion 15 as shown in FIG. 8A as an envelope of the trajectory drawn by the rod-shaped tool 7 by NC control of the spindle attached with the rod-shaped tool 7. While taking (moving) the locus of the radius R _{1 at} the large radius position R ₁ , the pressing of T _{1 to} T ₈ shown in FIG. 7B is performed up to the height dimension Y (about the height of the side wall) in advance. Then, the curved side 15 is molded,
Next, as shown by the arrow in FIG. 8 (a), the rod-shaped tool 7 is taken along the height dimension Y (the height of the side wall) while taking the envelope curve of the locus so that the radii become smaller as R ₂ , R ₃ , and R _{4 in} order. 7), the pressing of T _{1 to} T ₈ shown in FIG.
Mold 5. The role of the partial mold 16 is similar to that of the embodiment shown in FIG. Of course, the range of movement of the rod-shaped tool 17 under NC control is the range of the arrow, and the rod-shaped tool 1 under NC control
The control of 7 in the height direction (control of the amount of depression) is greater than the Y dimension.

At this time, as shown in FIG. 8B, the auxiliary mold 1 divided into quarter arcs that supports the lower side of the curved side portion 15 is formed.
You may use 6s2, 16s3, 16s4. When using the auxiliary molds 16s2, 16s3, 16s4 in this way,
When the trajectory of the rod-shaped tool 17 is successively reduced to R ₂ , R ₃ , and R ₄ , the auxiliary molds 16s2, 16s3, and 16s4 must be sequentially released downward. In this way auxiliary type 16s2, 16s
Whether or not 3, 16s4 is used may be selected by the wrinkle resistance depending on the thickness of the material 11 of the thin metal plate, the height of the straight side wall 13, and the like. According to this multistage diaphragm method, the number of operations is increased, but the depth dimension, here the Y dimension, can be made larger than that of the contour shape pressing method described above. That is, according to the multi-stage drawing method, the metal thin plate molded product 1 having a high side wall height dimension can be smoothly molded without causing wrinkles.

Next, the spinning method among the successive forming methods will be described with reference to FIG. This spinning method is a method in which the blanked portion is successively tapered in a tapered shape. That is, in the spinning method, as shown in FIG. 9, the rod-shaped tool 17 is pushed in the direction of the arrow while pressing the rod-shaped tool 17 against the material of the portion 15 based on the NC control, and the shape of the curved side portion 5 is sequentially divided. The mold is moved closer to the mold 16 and finally pressed against the partial mold 16 for molding. In the spinning method, as shown in FIGS. 9 (a) and 9 (b) based on NC control, the trajectory of the rod-shaped tool 17 is changed from T _{1 to} T ₈ (changing the pressing amount while changing the radius from the small radius state to the large radius state). ₈ is about the height of the straight side wall 13), and then the angle of the rod-shaped tool 17 is set to be tight and the pressing amount is changed from U _{1 to} U ₈ (changing the radius from a small state to a large state). also changed, to about the height of the straight side walls 13 at U _8.) and then, and then tightly angle to large state trajectories of the rod-shaped tool 17 from V ₁ ~V ₈ (small radius state The amount of pushing down is also changed while changing it to about the height of the straight part side wall 13 at V _8. ) Finally, the trajectory of the rod-shaped tool 17 based on NC control is W _{1 to} W _8.
As shown in FIG. 7B, the mold is pressed against the partial mold 16 to be molded.

As described above, although the number of steps is increased in the spinning method, the thin metal sheet molded product 1 having a higher side wall height dimension can be smoothly formed without wrinkling, as compared with the multi-stage drawing method. However, the corner portion 14
9A and 9B are deformed as shown in FIGS. 9A and 9B, it takes time and the same place is rubbed many times, so flaking may occur. Therefore, by reducing the number of times the same place is rubbed many times to eliminate the possibility of flaking, it is possible to produce a thin metal sheet product 1 by spinning from a thin metal sheet material 11 to produce a thin metal sheet product 1. By bending the straight side wall 13 of the material 11 and then spinning the curved side 15 of the corner 14, it is possible to produce a thin metal sheet product 1 with excellent appearance by preventing the occurrence of wrinkles. it can.

It is apparent that other methods may be used together during the processing in each of the successive forming methods shown in FIGS. 7 to 9 described above. FIG. 10 is a diagram showing an embodiment different from FIG. 5, and shows an embodiment in which the area of the corner portion serving as the curved side portion 15 is reserved extra during blanking.
The embodiment shown in FIG. 0 or the embodiment shown in FIG. 5 can be selected as needed. In FIG. 10, 1 is a thin metal plate molded product, 13 is a straight part side wall,
FIG. 10 is a view showing a stage where the straight line side wall 13 of the bent line AB is formed, and the curved side part 15 is in an unmolded state. In FIG. 10, since the ridge lines K and P are formed, the rigidity of the portion to be the curved side portion 15 surrounded by the ridge line KK is further improved. This rigidity is shown in FIG.
It plays an important role in performing the sequential molding method described in FIG. That is, if the portion that becomes the curved side portion 15 has no rigidity, the rod-shaped tool 17 moves according to the contour of the corner portion 14, and even if an envelope is drawn, before the plate material is plastically deformed in the plane. It will be bent out of the plane and wrinkles will occur. Therefore, in order to suppress the generation of wrinkles and the like, the ridge lines WW and X are necessary for successful main processing.

As described above, when the extra material is left in the portion to be the curved side portion 15, there is an advantage that the plate material of the curved side portion 15 is less likely to bend when the straight side wall 13 is bent. In addition, the tip portion 51 of the extra portion is attached to the rod-shaped tool 17
Clamp in a range that does not hit
It is possible to fix it to a table that supports 6 or pull it with a cylinder attached to the table that supports the partial mold 16, and it is possible to improve the molding limit by further eliminating waist bending and the like.

[0031]

According to the present invention, the following effects can be obtained. 1. By combining the bending process and the drawing process by sequential forming, a metal consisting of a box-shaped container with a large outer diameter and a relatively deep depth, such as a control box for storing electrical products, a refrigerator door, etc. The thin plate molded product can be manufactured without impairing the surface treatment. 2. When the side wall of the straight portion is bent in advance, the ridge line formed on the curved side portion contributes to the increase in rigidity when performing the successive forming work, so that it is possible to form a large area thin steel plate having a plate thickness of 3 mm or less. 3. Since the side wall of the straight part is formed by bending, there are no defects in the straight part such as warping and oil canning, unlike the straight part formed by drawing. This can be utilized to facilitate the combination (fitting) with other parts.

4. Even if the size of the control box or the door of a refrigerator is changed year by year, it is easy to cope with the design change because it does not require a large diaphragm die as in the conventional case. 5. If the dimension of the curved side portion that becomes the corner portion to be drawn is matched with the height dimension of the other side wall in the development view, it is possible to form a portion that does not require post-processing of this portion.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a metal thin plate molded product according to the present invention.

FIG. 2 is a flow chart showing a manufacturing process for manufacturing a thin metal plate product according to the present invention.

FIG. 3 is a development view showing an example of a raw material of a thin metal plate prepared for manufacturing a metal thin plate molded product according to the present invention.

FIG. 4 is a view showing a method of forming a straight-part side wall by bending a raw material of a thin metal plate to manufacture a thin metal plate-formed product according to the present invention, and FIG.
(B) is a side view thereof.

FIG. 5 is a diagram showing a state in which a straight line (broken line of A, B, C, and D) excluding a corner portion is bent in the development view shown in FIG. 3, and FIG. (B) is a sectional view taken along the line AA of the corner portion of (a).

FIG. 6 is a diagram showing an outline of a method of sequentially forming a corner portion to be a curved side portion left between the side wall portions of the straight line portion shown in FIG. 5A.

7A and 7B are diagrams showing a contour pressing method among the sequential forming methods shown in FIGS. 6A and 6B, FIG. 7A is a plan view showing a state where a corner portion is formed when viewed from above a reference plane, and FIG. (A) AA arrow view of the first embodiment of the tool depression, (c) is a BB arrow view of (a), and (d) is a second rod-like tool depression. FIG. 7A is a view showing the embodiment of FIG.

8 is a diagram showing a multistage drawing method which is a method different from that of FIG. 7 among the successive forming methods shown in FIG. 6, and FIG. 8A shows a state in which a corner portion is formed when viewed from above the reference surface. The top view shown, (b) is a BB arrow sectional view of the corner part of (a).

9 is a diagram showing a spinning method, which is a method different from those in FIGS. 7 and 8, among the successive forming methods shown in FIG.
(A) is a plan view showing a state in which a corner portion is formed when viewed from above the reference plane, and (b) is a view taken along the line BB of (a).

10 is a view showing an embodiment different from FIG. 5, and is a view showing an embodiment in which an area of a corner portion serving as a curved side portion is reserved extra during blanking.

[Explanation of symbols]

1 ... Metal thin plate molded product, 11 ... Thin metal plate material, 1
2 ... Reference surface 13 ... Straight part side wall, 14 ... Corner part, 15 ... Curved side part 15 '... Curved side part deformed part, 16 ... Partial type 16s2, 16s3, 16s4 ... Auxiliary type, 17 ... Rod-shaped tool 18 ... Roller , 19 ... Ball 21 ... Thin metal plate material preparation process, 22 ... Straight part side wall bending process 23 ... Corner part sequential forming process, 24 ... End face trimming process 41 ... Upper mold, 42 ... Lower mold, 43 ... plate restraint, 44 ...
Rubber pieces

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H05K 5/02 7301-4E H05K 5/02 M 5/04 7301-4E 5/04 (72) Inventor Teru Suzuki Futoshi 800, Odaira-cho, Shimotsuga-gun, Tochigi Prefecture, Hitachi, Ltd.Cryogenics Division, Hitachi, Ltd. Takehisa 292 Yoshida-cho, Totsuka-ku, Yokohama City, Kanagawa Prefecture

Claims (17)

[Claims] 1. A plurality of straight part side walls bent at a desired angle with respect to a front plate part of a thin metal plate, and a corner part formed by sequentially forming curved side parts between these straight part side walls. A metal thin plate molded product characterized by the above. 2. The metal thin plate molded product according to claim 1, wherein the thickness of the metal thin plate is 1.5 mm or less. 3. The thin metal plate product according to claim 1, wherein the depth of the side wall of the straight portion is about 1 cm to 8 cm. 4. The metal thin plate molded product according to claim 1, wherein the metal thin plate is a surface-treated steel plate. 5. A straight side wall of four sides bent at a desired angle with respect to a front plate portion of a thin metal plate, and four corners formed by sequentially forming curved side portions between the side wall of the straight side. And a metal thin plate molded article. 6. A metal thin plate molded product according to claim 5, which is a control box for housing electrical products. 7. The metal thin plate molded product according to claim 5, which is a refrigerator door. 8. A preparatory step of preparing a raw material for a metal thin plate, and a bending step of subjecting the raw material of the metal thin plate prepared in the preparatory step to a bending operation at a desired angle with respect to a reference surface of a linear portion side wall, And a step of successively forming a corner portion left between the side wall portions of the straight part processed in the bending step by a successive forming method. 9. A preparatory step of preparing a raw material for a metal thin plate, and a straight surface side wall of the raw material of the metal thin plate prepared in the preparatory step so as to prevent bending at a corner portion between the straight side wall portions. On the other hand, it has a bending step for bending at a desired angle, and a sequential forming step for forming a corner portion left between the side wall of the straight portion processed by the bending step by the sequential forming method. A method of manufacturing a characteristic thin metal plate product. 10. A preparatory step of preparing a material for a thin metal plate, and a straight surface side wall of the raw material of the thin metal plate prepared in the preparatory step so as to prevent bending at a corner portion between the straight part side walls. On the other hand, a bending process for performing a bending process at a desired angle and a corner portion left between the side wall of the straight part processed in the bending process are formed on the desired movement locus of the forming tool from the outside based on NC control. And a sequential forming step of forming by a sequential forming method according to 1. 11. A preparatory step of preparing a material for a thin metal plate, and a straight surface side wall of the raw material of the thin metal plate prepared in the preparatory step so as not to cause bending at a corner portion between the straight part side walls. On the other hand, a bending process in which a bending process is performed at a desired angle, and a corner part left between the side wall of the straight line processed in the bending process has a NC tool for a forming tool having a rotatable member at its tip. And a step of forming the corner portion from the outside by a successive forming method so as to take a desired movement locus, and a step of sequentially forming the sheet metal product. 12. A preparatory step of preparing a raw material for a metal thin plate, and a straight surface side wall of the raw material of the metal thin plate prepared in the preparatory step so as to prevent bending at a corner portion between the straight side wall portions. On the other hand, a bending process for performing a bending process at a desired angle and a corner part left between the side wall of the straight part processed in the bending process are performed from the partial mold installed inside and the outside based on NC control. And a desired forming path of the forming tool, and a successive forming step of forming by a successive forming method. 13. A preparatory step of preparing a material for a thin metal plate, and, in the raw material of the thin metal plate prepared in the preparatory step, the side wall of the straight part is used as a reference plane so as to prevent bending at the corners between the side wall of the straight part. On the other hand, a bending process for performing a bending process at a desired angle and a corner part left between the side wall of the straight part processed in the bending process are performed from the partial mold installed inside and the outside based on NC control. A successive forming step of forming by a successive forming method according to a desired movement locus and a desired movement locus in the depth direction that match the contours of the corners of the shaping tool. Production method. 14. The successive forming method in the successive forming step is a contour pushing down method.
A method for producing the thin metal plate molded article described. 15. The method for manufacturing a thin metal sheet product according to claim 8, wherein the successive forming method in the successive forming step is a multi-stage drawing method. 16. The sequential forming method in the successive forming step is a spinning method.
Alternatively, the method for producing a metal thin plate molded article according to 9 or 10 or 11 or 12 or 13. 17. In the material of the metal thin plate prepared in the preparing step, the development area is set so that the side wall height dimension of the corner portion is successively formed and then becomes substantially equal to the linear portion side wall height dimension. The method for producing a metal thin plate molded article according to claim 8, 9, 10 or 11 or 12 or 13.