JP2534356B2 - Drawing equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a draw forming apparatus that bends a plate material such as a flat steel plate and then performs draw forming.

(Prior Art) For example, when the shape of the drawn product as a whole bends and has a predetermined drawing depth along the bend, such as a trunk lid outer plate or a trunk lid inner plate of an automobile, There is a forming apparatus that bends and forms and then draws under the shape to reduce the drawing depth (see FIGS. 7 to 9).

In such a case, a blank flat plate material (hereinafter, referred to as a work W) for a molded component is put into a draw forming apparatus A in which the shape of the surface J of the die F is formed into a required concave curved shape, and a blank is formed. By pressing with the holder D, the central portion of the surface J of the die F is formed into a concave concave shape, and the entire work W is extended to the position where it is separated from the work W (hereinafter, referred to as the recess K). The shape is bent and the edge portion of the work W is clamped on the surface J of the die, and then the drawing punch E is operated to perform drawing work in the forming recess.

In this way, the overall shape of the work W is changed to the blank holder D
When the work W is bent by, it is necessary to fix the work W at a predetermined position on the surface J of the die F. Therefore, conventionally, the work W is fixed by using a movable gauge G as shown in the drawing. .

That is, the draw forming apparatus A includes an upper mold B and a lower mold C, a blank holder D and a punch E are provided on the upper mold B, and a movable gauge G and a positioning jig are provided on a die F for the lower mold C.
P, Q, and R are provided, and the movable gauge G is configured to be opened and closed by a pressing cylinder H.

Then, in this squeezing device A, the flat plate-shaped work W is supplied to a predetermined position on the surface J of the die F by the positioning jigs P, Q, and R, and the edge of the work W is positioned on the die face. To do.

Then, while operating the movable gauge G to adjust the position of the work W on the die, the edge of the work W is clamped between the surface J of the die and the blank holder D is lowered toward the work. Then, the bending process of the work is performed, and then the drawing process using the punch E and the die F is performed.

(Problems to be Solved by the Invention) By the way, in such a conventional technique, since the movable gauge G is configured, the structure is complicated, and the work W is positioned on the surface J of the die. It is in a state of being supported only by the upper and lower edges in FIG. 7 and by the left and right edges in FIG.
Is required to be fixed at a predetermined position on the surface J of the die, so that the movable gauges G installed on both sides of the work W are contacted with the work W at the same time, and are clamped before contacting the work W first. The movable gauge G causes the work W to move and causes variations in the processing position, and the adjustment is troublesome.

Further, at the left and right positions in FIG. 7, the recessed portion K is formed, and since the work W is not fixed in a floating state, the bending process in the blank holder D is likely to be misaligned.

The present invention has been made based on such a background, and an object thereof is to solve the problems of this type.

(Means for Solving the Problem) In order to achieve this object, the present invention is a draw-forming apparatus including an upper die and a lower die, wherein the upper die includes a punch and an outer periphery of the punch. An enclosing blank holder is provided, and the lower die is provided with a die having a molding concave portion in the central portion. In the one direction of the die surface, the central portion is low and the both sides are high. In addition to being bent to form a concave surface, the lower portion of the blank holder is formed into a convex shape that closely adheres to the concave shape of the die, and is a portion that is recessed by the bending on the surface of the die, and the blank holder. Install a gauge block at the position where the lower end surface of the die is on the outside of the die face, and make the gap between the inside surface of the gauge block and the outside surface of the blank holder slightly larger than the work thickness. At the same time, the upper surface of the gauge block is made to substantially match the height of the die face formed in the non-recessed portion of the die, and the edge of the work is placed on the upper surface of the gauge block. It is a draw forming device.

(Operation) According to the present invention, the gauge block is installed outside the die face at the recessed portion of the surface of the die provided in the lower die, and the upper surface of the gauge block is recessed in the surface of the die. The edge of the work is placed on the upper surface of this gauge block so that it matches the height of the die face formed in the part that is not inserted, so the work is oversized before bending on the die face on the die surface. It can be supported horizontally without causing any bending.

In addition, the gap between the inner surface of the gauge block and the outer surface of the blank holder is made slightly larger than the plate thickness of the work, and the upper surface of this gauge block is a die face formed on the surface of the die that is not recessed. Since the edge of the work is placed on the upper surface of this gauge block, the pressing operation of the blank holder causes the blank holder to contact the work in a stationary state for the first time. The edge of the work piece is immediately bent and inserted into the gap between the inner surface of the gauge block and the outer surface of the blank holder to form a guide portion on the work piece.

That is, in the work, the portion where the guide portion is formed is horizontally supported in a state where the deflection is small and is in a stationary state, and the guide portion is formed by the first contact of the blank holder with respect to the work portion. The position accuracy of the guide part is good.

Then, since subsequent molding is performed with reference to the guide portion having good positional accuracy as described above, the subsequent molding processing positional accuracy with respect to the work is also good, and the work piece is not displaced or wrinkled during the bending process by the blank holder. Can be prevented.

Therefore, according to the present invention, by simply installing the gauge block at a predetermined position on the surface of the die, the work during the bending process can be restrained with good positional accuracy by a simple structure.

Further, according to the present invention, since there is no operation part, the simultaneity of the operation is not required unlike the prior art,
No special adjustments are necessary for the simultaneity of actuation.

(Embodiment) The present invention will be described below with reference to an embodiment shown in the drawings.

The drawing apparatus S is composed of an upper mold 1 and a lower mold 2. The upper mold 1 is provided with a drawing punch 3 and a blank holder 4 surrounding the outside of the punch 3, and the lower mold 2 is separated from the die. In the center of the surface of the lower mold 2, a drawing recess 5 is formed, and the peripheral edge of the drawing recess 5 is in close contact with the lower end surface of the blank holder 4 over the entire circumference of the recess 5. A die face 6 is formed which is pressed by the above.

As shown in FIGS. 4 and 6, the entire surface of the lower mold 2 has a concave shape at the center thereof and is bent in a substantially V shape in a side view, and at the same time, the die face 6 is formed. Also has a similar concave shape, and a concave portion 8 is formed in the lower portion of the die face 6.

On the other hand, the punch 3 and the blank holder 4 provided on the upper die 1 are independently operated, and the blank holder 4
The punch 3 is lowered after the lowering step, and the blank holder 4 is raised after the raising operation of the punch 3 after the drawing process.

The blank holder 4 surrounds the punch 3 and has a lower end surface formed with a protrusion 7 having a substantially triangular shape corresponding to the shape of the die face 6 and protruding toward the lower mold 2. (See Fig. 6).

Then, when the flat plate-shaped work W is set on the die face 6 on the surface of the lower die 2, the edge of the work W is basically supported by the die face 6 (hereinafter, such a die face). The work support die face 6a)
However, in the recessed portion 8, the work W is separated upward from the upper surface of the die face 6.

When the blank holder 4 is abutted against this, the protrusions 7 first come into contact with the work W, and the protrusions 7 push down the work W to the position of the recessed portion 8 to perform a bending process.

That is, the flat work W is bent between the blank holder 4 and the die face 6, and in the case of this embodiment,
In order to make the drawing depth of the product substantially uniform, the entire work W is bent in a V shape.

Then, the blank holder 4 is stopped to the bottom dead center, and the work W bent by the punch 3 is fixed on the die face 6 over the entire circumference of the forming recess 5 in the bent shape. It functions as a blank holder.

On the lower surface of the blank holder 4 and the die face 6, there are formed ridges 11 and grooves 12 that surround the punch 3 and the molding recess 5, respectively, facing each other, and the work W is bent and held between them. However, when the punch 3 is used for drawing, the work W is prevented from being displaced and wrinkled.

Then, as shown in FIG. 2, the gauge block 13 according to the present invention is provided on the surface of the lower die 2 which is the portion where the surface is recessed and which is the outside of the die face 6 with which the blank holder 4 abuts. Various positioning devices for the work W on the die face 6 are arranged.

The gauge block 13 has a blank holder 4 on its inner surface.
The outer surface of the gauge block 13 facing the inner surface of the gauge block 13 is separated from the outer surface of the gauge block 13 by a distance slightly larger than the thickness of the work W, and the height of the upper surface of the gauge block 13 is set to the height of the work supporting die face 6a. They are aligned with each other and fixed on the surface of the lower mold 2 on the outside of the recessed portion 8 with bolts.

Positioning jigs 14 formed by standing up a plate material are installed side by side with these gauge blocks 13, respectively.
The position of the flat plate-shaped work W set on the upper surface in the horizontal direction in FIG. 2 is regulated.

Then, on the surface of the lower die 2, positioning jigs 15 and 16 are installed on the outside of the die face 6 which is in the direction orthogonal to the site where the gauge block 13 and the like are installed, and the die face of the flat work W is Positioning in the vertical direction in FIG.

The draw forming apparatus S having the above-described structure is provided with a third
As shown in FIG. 4 and FIG. 4, a work W made of a flat steel plate punched into a predetermined shape in advance is supplied to a predetermined position by a supply device such as a robot (not shown).

At this time, since the work W is supported by the work supporting die face 6a and the upper surface of the gauge block 13, even if the recess 8 is formed in the die face 6, there are many supporting points of the work W, and the work W It is possible to improve the accuracy of the processing position by supporting the tool in a state where it has less deflection.

Next, as shown in FIG. 6, when the blank holder 4 descends from above, the protrusions 7 formed on the blank holder 4
First contacts and presses the work W.

Thereby, the edge portion of the work W placed on the upper surface of the gauge block 13 is locally bent along the outer peripheral surface of the blank holder 4 between the upper surface of the gauge block 13 and the lower surface of the protrusion 7, As a result, a half-width tubular guide portion 10 is formed along the shape of the gauge block 13 on the work W, and the work W is engaged with the gauge block 13 until the work W reaches the bottom 9 of the recessed portion 8 and the die face 6 is engaged. It is possible to prevent the center position of the work W from shifting (FIG. 5).

Then, in this state, the blank holder 4 continues to descend, and the entire lower surface of the blank holder 4 reaches the die face 6, whereby the bending work of the entire work W is completed.

After that, the punch 3 of the upper die 1 starts to descend, and the punch 3
The lower surface of the punch W is pushed from the upper surface of the bent work W into the forming recess 5 to perform the drawing process, and the punch 3 reaches the bottom dead center as shown in FIG. 1 to complete the drawing process.

After that, the punch 3 and the blank holder 4 are lifted to separate the work W, thereby obtaining a draw-formed product in which the entire shape is bent in the uniaxial direction.

(Effect of the Invention) Since the present invention is configured as described above, the gauge block is installed on the outer surface of the die face, which is the recessed portion of the surface of the die provided in the lower die. Since the upper surface is made to substantially match the height of the die face formed in the non-recessed portion of the surface of the die and the edge of the work is also placed on the upper surface of this gauge block, the die surface on the die surface Thus, the work can be supported horizontally before the bending process without causing excessive bending.

In addition, the gap between the inner surface of the gauge block and the outer surface of the blank holder is made slightly larger than the plate thickness of the work, and the upper surface of this gauge block is a die face formed on the surface of the die that is not recessed. Since the edge of the work is placed on the upper surface of this gauge block, the pressing operation of the blank holder causes the blank holder to contact the work in a stationary state for the first time. The edge of the work piece is immediately bent and inserted into the gap between the inner surface of the gauge block and the outer surface of the blank holder to form a guide portion on the work piece.

That is, in the work, the portion where the guide portion is formed is horizontally supported in a state where the deflection is small and is in a stationary state, and the guide portion is formed by the first contact of the blank holder with respect to the work portion. The position accuracy of the guide part is good.

Then, since subsequent molding is performed with reference to the guide portion having good positional accuracy as described above, the subsequent molding processing positional accuracy with respect to the work is also good, and the work piece is not displaced or wrinkled during the bending process by the blank holder. Can be prevented.

Therefore, according to the present invention, by simply installing the gauge block at a predetermined position on the surface of the die, the work during the bending process can be restrained with good positional accuracy by a simple structure.

Further, according to the present invention, since there is no operation part, the simultaneity of the operation is not required unlike the prior art,
No special adjustments are necessary for the simultaneity of actuation.

[Brief description of drawings]

1 to 6 relate to an embodiment of the present invention, FIG. 1 is an overall sectional view of the apparatus taken along the line II of FIG. 2, FIG. 2 is a top view of the lower mold, and FIG. FIG. 4 is a sectional view of the lower mold corresponding to FIG. 1 when the punch and the blank holder are at the top dead center, FIG. 4 is a view on arrow IV in FIG. 3, and FIG. FIG. 6 is a sectional view corresponding to the drawing, FIG. 6 is a perspective view for explaining the relationship between the die face, the gauge block and the blank holder, FIGS. 7 to 9 show a conventional example, and FIG. 7 is a top view of the lower mold, 8 is an overall sectional view of the apparatus taken along the line VIII-VIII in FIG. 7, and FIG. 9 is a sectional view taken along line IX-IX in FIG. S: Drawing device, W: Work, 2; Die (lower mold), 3; Punch, 4; Blank holder, 6; Die face, 7; Projection, 8; Recessed part, 10; Guide part, 13; Gauge block.

Claims (1)

(57) [Claims] 1. A draw forming apparatus comprising an upper die and a lower die, wherein the upper die is provided with a punch and a blank holder surrounding the outer periphery of the punch, and the lower die is provided with a forming recess. In the case where a die having a central portion is provided, the surface of the die is low in the central portion in one direction,
While bending to form a concave shape on both sides, the lower part of the blank holder is formed into a convex shape that closely adheres to the concave shape of the die, and a portion that is recessed by the bending on the surface of the die. And a gauge block is installed at a position on the outer side of the die face where the lower end surface of the blank holder comes into close contact, and the gap between the inner surface of the gauge block and the outer surface of the blank holder is set to the plate thickness of the work. In addition to making it slightly larger, the upper surface of this gauge block is made to approximately match the height of the die face formed in the non-recessed portion of the die, and the edge of the work is placed on the upper surface of this gauge block. Characterizing drawing device.