JP2010167459A - Prismatic tube container forming method, and punch therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a prismatic tube container forming method, and a punch therefor capable of favorably forming a "prismatic tube container draw-shear container" having the large slenderness ratio out of a "cylindrical draw container" by using an existing draw-shear forming device without executing any multiple process draw-forming. <P>SOLUTION: A step of the length L1 and the step width (depth) W is provided on a fore end of a prismatic punch, and a prismatic draw-shear container is subjected to the draw-shear out of a cylindrical draw container 20 by using a step prismatic punch 100 and a prismatic die. The length L<SB>1</SB>satisfies the inequalities 1/2×(D<SB>0</SB>-L<SB>0</SB>)≤L<SB>1</SB>≤2/3×(D<SB>0</SB>-L<SB>0</SB>), and the step width W satisfies the inequalities 10/11×(t<SB>0</SB>-t<SB>2</SB>)≤W≤10/9×(t<SB>0</SB>-t<SB>2</SB>). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a method for forming a rectangular tube container and a rectangular punch, in particular, without diverting an existing drawing and ironing device without performing multi-step drawing, and having a uniform wall thickness distribution on the side wall and on the side wall. A method of forming a rectangular tube container and a rectangular tube forming punch capable of suitably producing a rectangular tube container having a large slenderness ratio without undulation of “bekobeko” (hereinafter referred to as “canning”, FIG. 7) It is.

Generally, a deep square tube container is made by multi-step drawing. That is, the coil is punched into a disk-shaped can called a “blank” by a press machine, and then drawn into a cylindrical container by a cylindrical punch and a circular die. Next, the elliptic cylinder punch presses the cylindrical container and passes through the drawing die so that the elliptic cylinder container is drawn. Next, the rectangular tube container is formed by the rectangular tube punch pressing the elliptical tube container and passing through the drawing die. Note that the actual drawing process is complicated, and each molding process is subdivided into multiple stages (see, for example, Patent Document 1).
FIG. 11 is an explanatory view showing a drawing portion when the square tube punch 600 presses the cylindrical ironing container 20 and passes through the drawing die 700.
The left half shows a state immediately before drawing, and the right half shows a state when the square tube punch 600 presses the cylindrical ironing container 20 and passes through the drawing die 700. The plate thickness t ₀ is the blank plate thickness, and the plate thickness t ₁ is the plate thickness of the side wall after the cylindrical or elliptical cylinder ironing process. As seen, the square tube punch 600 moves while pressing the bottom of the cylindrical ironing container 20, a cylindrical ironing container 20 is squeezed by the forming die 700 stop, reduced at the same time the plate thickness is uniformly t ₂ of the side wall portions Meated. And the change rate of this side wall board thickness changes with the height positions of a cylindrical ironing container. In particular, the rate of change is large in the vicinity of the bottom outer edge, and as a result, the stress is excessively concentrated in the drawing and ironing process, which may lead to a broken body (break).
Also, instead of forming the rectangular tube container by multi-step drawing as described above, the bottom of the rectangular tube container or a similar pellet is previously formed, and the intermediate cup body is formed from the pellet by impact molding. Next, a method of manufacturing a rectangular battery can is known in which a desired rectangular battery can is formed by drawing and ironing the intermediate cup body by a DI method (see, for example, Patent Document 2). In order to prevent cracks and breaks due to stress concentration during the drawing and ironing process, the literature relating to the above invention includes the “thickness of the long side plate” and the “bottom part” for each thickness of the intermediate cup body. The ratio to “thickness of” is 0.6 to 1.3, and the ratio of “thickness of the short side plate” to “thickness of the bottom” is adjusted to the range of 1.0 to 1.8. Is disclosed. In addition, in order to suppress the material surplus phenomenon between the ironing die and the punch and smooth the flow of the material, the intermediate cup is formed using a DI punch in which processing grooves are formed in a lattice shape on the side of the long side. It is also disclosed that the body is drawn and ironed.

JP-A-9-306441 JP 2003-208876 A

The prior art of multi-step drawing has the problem that many types of punches and “drawing dies” are required.
Further, in the conventional technique of pellet and impact molding, it is necessary to newly introduce an apparatus for molding a pellet and an impact molding apparatus for molding an intermediate cup body.
Further, forming the processing grooves on the side surfaces of the long sides like the DI punch has a problem that an extra manufacturing cost is generated.
Therefore, the present invention was devised in view of the above circumstances, and its purpose is to have a uniform thickness distribution on the side wall while diverting an existing drawing / ironing device without performing multi-step drawing. It is another object of the present invention to provide a method for forming a rectangular tube container and a rectangular tube container forming punch capable of suitably manufacturing a rectangular tube container having a large slenderness ratio without side wall canning.

In order to achieve the above object, according to a method for forming a rectangular tube container according to claim 1, a blank is formed into a bottomed cylindrical or elliptical tube container (hereinafter referred to as a cylindrical container) by drawing, and then the cylindrical container is formed. Molding into a “cylindrical ironing container” by ironing, and then forming the “cylindrical ironing container” into a “square tube-squeezing ironing container” by square-punching and ironing with a square punch and square die. A method,
When the square punch is inserted into the square die and formed into a “square tube squeezing and squeezing container”, the thick plate portion related to the “turned part” of the “cylindrical squeeze container” is replaced with the square die and the square punch. The "cylindrical ironing container" is drawn and ironed into the "square tube ironing container" without performing the ironing process.
In the above method for forming a square tube container, when a cylindrical ironing container is finished into a square tube, the thick plate portion corresponding to the particularly thick “bottom folded portion” is not subjected to ironing by a square die and a square punch. Suppressing the concentration of stress excessively on the part, and suitably preventing the broken body. Further, when ironing with a square die and a square punch, except for the “bottom folded portion”, the thickness distribution of the side walls is made uniform, and as a result, the occurrence of canning on the side walls is suitably suppressed.
In this way, cylindrical or elliptical cylinder ironing is applied, the side wall thickness of the “cylindrical ironing container” is made uniform, and the plate thickness related to the “bottom folded part” is released from the “ironing process” using the square die. However, a square tube container having a large slenderness ratio can be easily produced from a “cylindrical ironing container” by finishing it into a square tube.

In the method for forming a rectangular tube container according to claim 2, the rectangular punch is a tapered rectangular punch having a step at the tip.
In the above method for forming a rectangular tube container, by providing a step at the tip of the square punch, the plate thickness corresponding to the particularly thick “bottom folded portion” can be suitably escaped from “scoring” by the square die. Is possible.

In the method for forming a rectangular tube container according to claim 3, the axial length of the step is such a length that a side surface of the step can envelop a surface related to the “folded portion”.
In the above method for forming a rectangular tube container, it is possible to release a thick plate portion corresponding to a particularly thick “bottom folded portion” from “scoring” by a square die and a square punch.

In the method for forming a rectangular tube container according to claim 4, the depth (width) of the step is a depth at which the ironing rate in the “folded portion” becomes zero.
In the above method for forming a rectangular tube container, the plate thickness corresponding to the “bottom folded portion” having a particularly large plate thickness can be suitably escaped from the ironing process using the square die.

In the method for forming a rectangular tube container according to claim 5, an ironing ratio R ₁ (%) with respect to the blank plate thickness of a side wall portion of the “cylindrical ironing container” is 0 <R ₁ ≦ 80 (%). It was decided.
In the molding method of the square tubular container, the ironing ratio R ₁ of the side wall portion by setting the above range, when due rectangular die "ironing", can be suitably prevented Yabudo ironing site as Become.

In the method for forming a rectangular tube container according to claim 6, an ironing ratio R ₂ (%) with respect to a side wall plate thickness of the “cylindrical ironing container” at the side wall portion of the “square tube ironing container” is 0 <R _2. ≦ 50 (%).
In the method of forming the rectangular tube container, by setting the squeezing rate R ₂ of the side wall portion within the above range, it is possible to suitably prevent the squeezing and squeezing part from being broken during “drawing and squeezing processing” with a square die. However, it is possible to suitably uniformize the thickness distribution of the side walls. Accordingly, it is possible to easily produce a rectangular tube container having a large slenderness ratio from the “cylindrical ironing container” while suitably suppressing the occurrence of canning in the side wall portion.

In order to achieve the above object, the rectangular tube container forming punch according to claim 7 cooperates with a square die in cooperation with a square die for a “cylindrical ironing container” obtained by drawing and ironing a blank. A square punch that performs cylinder drawing and ironing to form a square tube ironing container,
The thick plate portion related to the “folding portion” of the “cylindrical ironing container” is configured not to be ironed by the square die and the square punch.
In the said square tube container shaping | molding punch, the shaping | molding method of the square tube container of the said Claim 1 can be implemented suitably.

In the rectangular tube container forming punch according to claim 8, the rectangular punch is a tapered rectangular punch having a step at the tip.
In the said square tube container shaping | molding punch, the shaping | molding method of the square tube container of the said Claim 2 can be implemented suitably.

In the rectangular tube container forming punch according to claim 9, the axial length of the step is a length that allows the side wall surface of the step to envelope the thickness of the “folded portion”. .
In the said square tube container shaping | molding punch, the shaping | molding method of the square tube container of the said Claim 3 can be implemented suitably.

In the rectangular tube container forming punch according to claim 10, the depth (width) of the step is a depth at which the ironing rate at the “folded portion” becomes zero.
In the rectangular tube container forming punch, the method for forming the rectangular tube container according to claim 4 can be suitably implemented.

According to the method of forming a rectangular tube container of the present invention, the thickness distribution of the side wall is uniform from the “cylindrical iron container” while diverting the existing drawing and ironing apparatus without performing multi-step drawing. And it becomes possible to manufacture suitably a rectangular container with a large slenderness ratio without a canning on a side wall.
In addition, according to the rectangular tube container forming punch of the present invention, the method of forming the rectangular tube container of the present invention can be suitably implemented.

  Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings. Note that the present invention is not limited thereby.

FIG. 1 is an explanatory view showing a stepped square punch 100 according to the present invention. FIG. 1A is a front view and FIG. 1B is a bottom view.
This step-shaped square punch 100 is formed in a “cylindrical ironing container” (20 in FIG. 5) obtained by drawing and ironing a blank, with a square die near the bottom outer edge (bottom folded portion) having a particularly large thickness. A step is provided at the tip so as not to perform ironing processing (not shown). The configuration includes a tip 1 for releasing the vicinity of the bottom outer edge of the “cylindrical ironing container” 20 from the ironing process by the square die, and a main body 2 for forming the side wall other than the bottom of the “cylindrical ironing container” into a “square tube”. It is composed of

Tip 1, is L ₁ length. Although details will be described later with reference to FIGS. 1 and 2, L ₁ is determined by “one side length of the cross section of the tip 1” L ₀ and “cylindrical ironing container outer diameter” D ₀ . As numerical examples, L ₀ = 50 mm, L ₁ = 15 mm, W = 0.3 mm, and R = 10 mm. In addition, the joint part of the front-end | tip part 1 and the main-body part 2 is a taper.

  The hatched portion in FIG. 1 (b) is an escape zone 3 for releasing the thick plate portion near the outer edge of the bottom of the “cylindrical ironing container” from the drawing and ironing when the cylindrical ironing container 20 is drawn and ironed by a square die. It is.

FIG. 2 is an explanatory diagram showing the step length L ₁ at the tip of the step square punch 100 of the present invention.
The step length L ₁ at the tip of the punch is one side long so that the thick “bottom folded portion” S of the cylindrical ironing container 20 can be released from ironing with a square die (not shown) and a square punch. The region of L ₀ × step length L ₁ is determined so as to envelop the “bottom folded portion” S. Therefore, for example, as the step length L ₁ ,
1/2 × (D ₀ −L ₀ ) ≦ L ₁ ≦ 2/3 × (D ₀ −L ₀ )
L _{1 in} the range can be adopted.
Incidentally, ironing cans For containers ironing elliptic cylinder, employing a minor as D _0. On the other hand, when the square tube squeezing and squeezing container has a rectangular cross section (when the square punch is a rectangular punch), a short side is adopted as L ₀ as shown in FIG.

Further, the step width W is determined by the ironing rate of the bottom folded portion S. For example, when the ironing rate is zero, as shown in FIG. 4, t ₀ = W + t ₂ , that is, W = t ₀ −t ₂ (t ₂ : other than “bottom folded portion” S of the rectangular tube squeezing iron container Side wall plate thickness, t ₀ : blank plate thickness).
However, as the actual step width W, for example,
10/11 × (t ₀ −t ₂ ) ≦ W ≦ 10/9 × (t ₀ −t ₂ )
W in the range can be adopted.

FIG. 5 is an explanatory view showing a step of forming a square tube squeezed iron container. In addition, the upper stage shows each plan view, and the lower stage shows each of these sectional views. 5A shows a cylindrical squeezed container, FIG. 5B shows a cylindrical squeezed container, FIG. 5C shows a rectangular tube squeezed container, and FIG. 5D shows a rectangular squeezed squeeze container. In addition, since the occurrence of canning cannot be suppressed in the rectangular tube squeezed container of (c) (see Fig. 7), in this case, from the cylindrical squeezed container of (b) to the (d) rectangular squeezed and squeezed container in one step. Molded to eliminate the occurrence of canning.
This forming step is adapted to apply ironing of a cylinder or an elliptic cylinder to the blank when forming the square tube drawn iron container 40, and after forming into a cylindrical or elliptic cylinder ironing container with a uniform side wall, the step square of the present invention. A square tube is finished using the punch 100. In this way, while adapting the ironing of a cylinder or an elliptic cylinder to a uniform side wall thickness, the plate thickness relating to the “bottom folded portion” S is released from the “ironing process” using a square die and a square punch. By finishing it into a square tube, a “square tube squeezed iron container” 40 having a large slenderness ratio can be easily produced from the “cylindrical iron container” 20. Hereinafter, each step will be described.

First, in the cylindrical drawing process, a coil (material: 3003-H14, plate thickness t ₀ = 0.75 mm, PP laminate thickness = 30 μm) is formed into a disk-shaped can material (φ107.5 mm) called “blank” by a press machine. A shallow cylindrical squeeze container shown in FIG. 5 (a) is formed by punching, mounting the blank on a blank holder (not shown), and moving the cylindrical punch while pressing the blank with a cylindrical punch (φ71.5) (not shown). 10 is drawn. The plate thickness of the cylindrical squeeze container 10 is substantially the same as the blank plate thickness t ₀ .

Next, in the cylindrical ironing process, the cylindrical punch further presses the cylindrical drawn container 10 and passes through an annular ironing die having a clearance of 0.65 mm from the punch, whereby the side wall plate of the cylindrical drawn container is used. The thickness is reduced, and a deeper cylindrical ironing container 20 shown in FIG. 5 (b) is formed. Note that the thickness t ₁ of the upper side wall of the cylindrical ironing container is reduced from 0.75 mm (= t ₀ ) to 0.65 mm.
Further, the ironing ratio R _{1 with} respect to the blank plate thickness at that time is R ₁ = 100 × (t ₀ −t ₁ ) / t ₀ = 100 × (0.75−0.65) /0.75=13.3 [%].

FIG. 6 is an explanatory view showing the plate thickness distribution of the side wall of the cylindrical ironing container 20.
As can be seen from the figure, the thickness of the side wall at 10 mm ≦ height ≦ 30 mm is substantially uniform by the ironing process.

Next, in the rectangular tube drawing step, the stepped rectangular punch 100 and the square die (not shown) are used to draw the cylindrical ironing container 20 into a rectangular tube shape, and the rectangular tube drawing container 30 shown in FIG. Is made. Since the stepped square punch 100 is provided with a step at the tip, the thick portion (the bottom folded portion S in FIG. 2) of “the vicinity of the outer edge of the bottom of the cylindrical ironing container 20” is completely sagged by a square die. It will not be broken (the ironing rate = zero). FIG. 7 is a perspective view of the rectangular tube drawn container 30 produced by the drawing. As can be seen from the figure, a hatched portion (z portion) exists on the side wall of the rectangular tube throttle container 30. At this time, there are two types of plate thicknesses t ₀ and t ₁ on the side wall of the rectangular tube squeezed container 30, and the side wall is undulated by canning. In order to obtain the elongated rectangular tube container which is the object of the present case, it is necessary to perform the drawing and ironing process described later. If ironing is performed on the thick z portion with a conventional square punch, there is a risk that the metal will not move and may be broken. However, since the stepped square punch 100 of the present invention has a tapered step at the tip, no ironing is performed on the z portion with a square die. As a result, as will be described later, it is possible to iron and mold into a tall rectangular tube container while avoiding breakage.

FIG. 8 is an explanatory view showing the thickness distribution of the side wall of the rectangular tube throttle container 30.
As can be seen from the figure, the thickness of the corner portion is almost uniform, but the thickness of the side portion varies greatly.

Next, in the square tube ironing step, ironing is performed on the side wall of the cylindrical ironing vessel 20 toward the opening end using the step square punch 100 and the square die 4 (FIG. 4). Thereby, the cylindrical ironing container 20 can be formed into a square tube-drawing ironing container 40 (FIG. 5 (d)) that is taller and has a uniform side wall thickness. Therefore, as shown in FIG. 9, the side wall of the square tube squeezing and squeezing container 40, which is the final product,
(1) Blank plate thickness (t ₀ ), z part (2) Side wall plate thickness after cylindrical ironing (t ₁ )
(3) Side wall plate thickness after square tube ironing (t ₂ )
Will exist. The side wall of the square tube squeezing and squeezing container 40 has no canning and is a beautiful and slender smart square tube container. Therefore, the difference from the conventional container is clear.

Further, the ironing ratio R _{2 with} respect to the side wall thickness of the cylindrical ironing container is the side wall thickness t ₁ = 0.65 mm of the cylindrical ironing container, and the side wall thickness t ₂ after the square ironing process is 0.50 mm.
R ₂ = 100 × (0.65−0.50) /0.65=23.1 [%].

FIG. 10 is an explanatory view showing the plate thickness distribution of the side wall of the square tube squeezing and squeezing container 40.
As can be seen from the figure, the thickness of the side walls of the side and corner portions of the square tube squeezing and squeezing container 40 is uniform.

  As described above, according to the method for forming a square tube drawn ironing container using the stepped square punch 100 according to the present invention, the side wall thickness distribution is uniform and the side wall has no canning without multi-step drawing. It becomes possible to easily mold a rectangular tube drawn ironing container having a large slenderness ratio.

  The method for forming a square tube squeezed iron container and the stepped square punch 100 of the present invention can be suitably applied to forming a square tube squeezed iron container, particularly a square tube squeezed iron container having a large slenderness ratio.

It is explanatory drawing which shows the level | step difference square punch of this invention. The step length L ₁ of the distal end portion of the step prismatic punch of the present invention; FIG. The step length L ₁ of the distal end portion of the step prismatic punch of the present invention; FIG. It is explanatory drawing which shows the level | step difference width W of the front-end | tip part of the level | step difference square punch of this invention. It is explanatory drawing which shows the formation process of the square tube container using the level | step difference square punch of this invention. It is explanatory drawing which shows plate | board thickness distribution of the side wall of a cylindrical ironing container. It is a perspective explanatory view showing a rectangular tube throttle container according to the present invention. It is explanatory drawing which shows plate | board thickness distribution of the side wall of the square tube | pipe drawn container which concerns on this invention. It is a perspective explanatory view showing a square tube squeezing iron container according to the present invention. It is explanatory drawing which shows the plate | board thickness distribution of the side wall of the square tube ironing container which concerns on this invention. It is explanatory drawing which shows the drawing and ironing shaping | molding by the conventional square punch and square die.

DESCRIPTION OF SYMBOLS 1 Tip part 2 Body part 3 Escape zone 4 Square die 10 Cylindrical squeeze container 20 Cylindrical squeeze container 30 Square tube squeeze container 40 Square tube squeeze squeeze container 100 Step square punch

Claims (10)

A blank is formed into a bottomed cylindrical or oval cylindrical container (hereinafter referred to as a cylindrical container) by drawing, then the cylindrical container is formed into a “cylindrical iron container” by ironing, and then the “cylindrical iron container” is formed. A method of forming a rectangular tube container, which is formed into a “square tube drawn ironing container” by a rectangular tube drawing and ironing process using a square punch and a square die,
When the square punch is inserted into the square die and formed into a “square tube squeezing and squeezing container”, the thick plate portion related to the “turned part” of the “cylindrical squeeze container” is replaced with the square die and the square punch. A method of forming a rectangular tube container, comprising drawing and ironing from the “cylindrical iron container” to the “square tube ironing container” without performing the ironing process.   The method for forming a rectangular tube container according to claim 1, wherein the square punch is a tapered square punch having a step at a tip portion.   3. The method for forming a rectangular tube container according to claim 1, wherein the axial length of the step is a length by which a side surface of the step can envelop a surface related to the “folded portion”.   4. The method for forming a rectangular tube container according to claim 1, wherein a depth (width) of the step is a depth at which an ironing rate in the “folded portion” becomes zero. 5. 2. The method for forming a rectangular tube container according to claim 1, wherein an ironing ratio R ₁ (%) of the side wall portion of the “cylindrical ironing container” with respect to the blank plate thickness is 0 <R ₁ ≦ 80 (%). The corner according to claim 1, wherein the ironing ratio R ₂ (%) of the side wall portion of the “square tube squeezing container” with respect to the side wall plate thickness of the “cylindrical ironing container” is 0 <R ₂ ≦ 50 (%). A method for forming a cylindrical container. With a square punch that forms a "square tube squeezed iron container" by cooperating with a square die to form a "square tube squeezed iron container" for a "cylindrical iron container" obtained by drawing and ironing a blank. There,
When the square punch is inserted into the square die and formed into a “square tube squeezing and squeezing container”, the thick plate portion related to the “turned part” of the “cylindrical squeeze container” is replaced with the square die and the square punch. A rectangular tube container forming punch characterized in that the ironing process is not performed.   The square tube container forming punch according to claim 7, wherein the square punch is a tapered square punch having a step at a tip portion.   The rectangular tube container forming punch according to claim 7 or 8, wherein the axial length of the step is such a length that a side wall surface of the step can envelop a surface related to the "folded portion".   9. The rectangular tube container forming punch according to claim 7, wherein the depth (width) of the step is a depth at which the ironing rate in the “folded portion” becomes zero.

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