JPH0381026A - Strip material for progressive drawing press and method for pressing it and press die therefor - Google Patents

Abstract

PURPOSE:To improve the yield of material for a product by pressing a bendable part a prescribed pressing length alone in a width direction from the projecting side to forcedly extend it a prescribed extendable length alone in the feed direction of a connecting member. CONSTITUTION:The bendable part 28 which is projected in the width direction is provided on the connecting member 3. When the bendable part 28 is pressed a prescribed pressed length T alone from the projecting side in the direction of width L, a connecting member length A is extended forcedly a prescribed extendable length DELTAA alone in the feed direction of the connecting member 3. The bendable part 28 is pressed a prescribed pressing length alone from the projecting side to forcedly extend the connecting member 3 and to easily keep the pitch between blanks in a prescribed pitch. Thus, the precision of the pitch can be improved.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a strip material for progressive drawing repress, a pressing method therefor, and a press die therefor, and more specifically relates to a strip material for progressive drawing repress, and a press die therefor. In response to the reduction in blank length, progressive drawing repress makes it easier to maintain the inter-blank pitch at a predetermined pitch by extending the connecting member between the blanks by a predetermined extension length in the feeding direction. It relates to strip materials, pressing methods, and press dies for the same.

[Prior Art] As is well known, various products are processed by drawing repress. In order to improve the work efficiency in the above-mentioned drawing repressing, a technique of sequentially feeding the processed material and drawing repressing is widely used.

Here, for the above-mentioned progressive drawing repressing, the processing material is a band-shaped strip material, and this strip material is punched out to connect the front blank and the subsequent blank of the blank to be drawn and repressed with a connecting member. In addition to having a shape similar to this, a strip material is sometimes used in which a plurality of blanks are connected in multiple stages and the overall shape is approximately band-shaped. At this time, it is important that the inter-blank pitch between the center of the preceding blank and the center of the subsequent blank is equal to the feed pitch of the sequential feeding.

However, when the blank is subjected to the drawing and repressing, the blank length of the blank may be reduced. That is, the length between the connection points between the connection point on the front side and the connection point on the rear side of the connection point between the blank and the connection member of the blank to be drawn and repressed is reduced. In order to maintain the pitch between the blanks at a predetermined pitch in response to the reduction in the length between the connecting points, the following conventional technology is available.

That is, side edges of an arbitrary edge width are provided as connecting members on each of both sides of the strip material in the longitudinal direction, that is, the feeding direction, and the blank is provided between these side edges;
The side edge portion and the blank are connected by a lance.

Incidentally, slits are suitably made in the strip material to provide the blank between the side edges and to form the lance. In this case, the lance is deformed due to the reduction in the length between the connecting points, but the length of the side edges in the feeding direction does not change, so these side edges keep the beams between the blanks at a predetermined pitch. It is something to keep.

Further, the other connecting member does not have the side edge portion,
There is one in which the front blank and the rear blank are connected by a narrow strip-shaped connecting member.

Note that the blank and the narrow strip-shaped connecting member are formed by punching out a portion of the strip material other than the blank and the narrow strip-shaped connecting member. In the narrow strip-shaped connecting member, a substantially U-shaped absorbing portion is formed approximately at the center of the front blank and the rear blank. In this samurai, as the length between the connecting points is reduced, the connecting member is pulled toward both ends, and the absorbing portion deforms due to its elasticity to absorb the reduction in the length between the connecting points. , which attempts to maintain the pitch between the blanks at a predetermined pitch.

[Problems to be Solved by the Invention] According to the prior art described above, it is possible to some extent to maintain the inter-blank beaches 7 at a predetermined pitch even though the blank length is reduced.

Here, in the case of the strip material that connects the side edge and the connecting part with the lance, the lance is deformed but the side edge is not deformed, so it is easy to improve the accuracy of the pitch between the blanks.

However, in order to provide the side edges, it is necessary to increase the width of the strip material in the feeding direction by the width of the blank in the feeding direction plus the edge clearance of the side edges. For this reason, it is difficult to reduce the amount of material required for the strip material for each blank, that is, it is difficult to improve the material yield of the drawn and repressed product.

In the case of the connecting means having the substantially U-shaped blank length reduction absorbing member, the side edge member is not required, so that the width of the strip material in the feeding direction is approximately the same as the width of the blank in the feeding direction. It can be done. Therefore, it is easy to reduce the amount of material required for the strip material for one of the blanks.

In other words, it is easy to improve the retention of the material in the product obtained by drawing and repressing. However, the deformation of the absorbing portion to maintain the pitch between the blanks is due to the elasticity of the material itself constituting the strip material, and the deformation of the absorbing portion to maintain the deformed state of the absorbing portion is due to the elasticity of the material itself that makes up the strip material. Since there was no means to do so, the deformed absorbing portion sometimes returned to the state before being deformed in the feeding step after the drawing and repressing step. That is, the connecting member that has been expanded in the drawing and repressing process may be reduced to the state before being expanded in the feeding process.

For this reason, it is difficult to extend the connecting member by a predetermined extension length corresponding to the reduction in the length between the connecting points, and it is therefore difficult to increase the precision in maintaining the pitch between the blanks at a predetermined pitch.

[Object] Therefore, the object of the present invention is to press the connecting member of the strip material, which is formed by connecting the blanks in multiple stages by connecting members, in the width direction by a predetermined compression length, so that the connecting member has a predetermined extension length. By forcibly stretching the blanks, it is easy to improve the material yield of the drawn and repressed product, and it is also possible to increase the precision in maintaining the pitch between the blanks at a predetermined pitch. The present invention provides a strip material, a pressing method therefor, and a press mold therefor.

[Means for Solving the Problems 1] The present invention has the following technical means for solving the above problems. That is, to explain this using the reference numerals used in the attached drawings corresponding to the embodiments, the preceding blank and the subsequent blank of the blank to be progressively drawn and repressed are connected, and the center of the preceding blank and the subsequent blank are connected. In the strip material, which has a connecting member for maintaining a pitch between the blanks at a predetermined pitch between the centers of the blanks, and in which a plurality of blanks are connected in multiple stages in the feeding direction of the progressive drawing repress: the connecting member 3 has a bendable portion 28 that is convex in the width direction of the strip material l, and when this bendable portion 28 is pressed by a predetermined pressing length T from the convex side in the width direction, the above-mentioned Connecting member length A of the connecting member 3 in the feeding direction S
This is a strip material for progressive drawing repress, characterized in that the strip material is forcibly extended by a predetermined extension length ΔA.

The press die for sequentially feeding and drawing and repressing the strip material 1 is a press die that feeds the strip material at a predetermined feeding pitch and has a drawing punch and a drawing die for drawing and repressing the blank of the strip material. In the width direction of the strip material 1 of the connecting member 3 between the blank 2 which is drawn and repressed by the drawing punch 7 and the drawing die 8 and each of the preceding blank 2 and subsequent blank 2 of this blank 2; A pressing surface 18 for pressing the flexible portion 28 which is formed into a convex shape from the convex side in the #AL direction, and a pressing surface 16 for pressing the flexible portion 28 by a predetermined pressing length T. A press die for progressive drawing repress characterized by having a pressing surface reciprocating means for causing the pressing surface 16 to reciprocate G in the width direction can be used.

With the above configuration, in the pressing method in which the blank of the strip material sent to the press die is drawn and repressed; According to the reduction length ΔB of the inter-connection point length B between the connection point F with the front stage of the connection point F with the connection member 3 of the blank 2 and the connection point F with the rear stage, the connection member 3 is moved along the feeding direction S. I of the strip material 1 in order to extend the connecting member length A by a predetermined extension length ΔA.
The bendable portion 28 of the connecting member 3 is convex in the l@L direction.
For progressive drawing repress characterized in that the connecting member 3 is forcibly extended by pressing the blank by a predetermined pressing length T from the side of the die, thereby making it easier to maintain the pitch P between the blanks at a predetermined pitch. This press method can be realized.

Therefore, the above-mentioned side edges are not required as the connecting member 3, and therefore the width of the strip material 1 can be made approximately the same as the width of the blank. Therefore, it is easy to improve the material yield of the drawn and repressed product, and the connecting member 3 is forcibly extended in the feeding direction S by pressing the flexible portion 28 of the connecting member 3.

Therefore, it is easy to set the extension length ΔA of the connecting member 3 to a predetermined length, and therefore it is easy to increase the accuracy when setting the pitch P between blanks to a predetermined pitch.

[Example] Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

This example shows an example in which the present invention was implemented in progressive drawing repressing for manufacturing a substantially circular plate metal fitting used in a flow 2P disk.

The above-mentioned approximately circular plate metal fitting is a strip material 1 made of stainless steel plate.
The material is manufactured through a blank punching press process, a drawing repress process, a center hole punching process, a center hole opening bending process, a drive hole punching process, and a product punching process. The strip material l is provided with a plurality of blanks 2 corresponding to each step of the above steps and blank steps provided between each step, and the blanks 2 are connected by connecting members to form a whole. A strip material l having a plurality of blanks 2 is constructed. Then, an inter-blank pitch P between the centers of the adjacent blanks 2 is determined.The blank diameter R of the blank 2 changes from the diameter R1 to the diameter R2 before and after the drawing repress. It is intended to be reduced to . By reducing the blank diameter R, the length B between the connecting points with the connecting member is reduced from the length BL to the length B2 by a length Δ
It can be reduced by B.

The above are the same parts as the conventional one, and in order to solve the above-mentioned problems, this strip material l according to the present invention is made as follows. That is, as shown in FIGS. 1, 2, and 3, the connecting member has a narrow strip-shaped connecting member 3 formed in a substantially dogleg shape, and this connecting member 3 connects the blank 2 and the adjacent blanks. Two of them are arranged between the two. The two connecting members 3 are arranged symmetrically with respect to the center of the width of the strip material 1. Each of the connecting members 3 has a bendable portion 28 at the tip of the bent portion of the dogleg shape, and this bendable portion 28 is convex from the center in the width direction of the strip material 1 toward the outer edge. It is connected to the preceding blank 2 and the subsequent blank 2 at connection points F at both ends of the dogleg shape. In the connecting member 3, the length A of the connecting member along the feeding direction S is equal to the length Al before the drawing repress.
It is formed by a punching press so that it becomes .

In order to squeeze and repress the strip material 1, the following press mold 4 can be used. That is, the press die 4 is constructed by constructing the upper die 5 shown in FIG. 4 and the lower die 6 shown in FIG. 5 as shown in FIG. Punching press position Ql, middle punching press position 2tQ2, drawing repress position Q3, center hole punching press position Q4. Center hole opening bending position Q5, drive hole punching press position Q6. Further, a punch 7, a die 8, and a knockout 9 for each pressing process are arranged at each press position IQ of the product punching position fiQ7, thereby making it possible to carry out the above-mentioned progressive repressing process. The press mold 4 is equipped with a punch lO for punching pilot holes and a punch 11 for punching pilot holes. Positioning bin! 2, etc., a fixing surface 13 for holding and fixing the blank 2, a pressing surface 14 for flattening the drawn and repressed processed portion, and a guy 11 for supporting both sides of the strip material 1 in the feeding direction.
5 etc. are also provided, but their detailed description will be omitted.

The above parts are substantially the same as those of the conventional press mold, and in order to solve the above problems in this embodiment of the present invention, the following steps are taken. # Four pressing surfaces 1G and those pressing surfaces 18
It has four pressure surface reciprocating means for reciprocating G. The pressing surface reciprocating means includes a pressing piece 17 disposed on the upper die 5 and a slider 18 disposed on the lower die 6. The pushing piece 17 is formed with a contact surface 2o for pushing the slider 18 by hitting the roller 18 of the slider 18 as the upper die 5 descends. The slider 18 is disposed within a slider hole 21 formed in the lower die 6 so as to be reciprocating. This slider 18 is connected to a slider body 22 as shown in FIG.
The roller 19 is rotatably mounted on a shaft 23 and has a pressing member 25 disposed in a pressing member arranging groove 24 formed on the upper surface.

The pressing surface 16 is formed within a guide groove 26 at the tip of the pressing member 25 . A protrusion length adjusting piece 27 is attached between the rear end of the pressing member 25 and the pressing member @24. Here, compared to the thickness Ea of each of the protrusion length adjustment pieces 27a of the two sliders 18 on the rear side in the feed direction S, that is, on the rear stage side, of the four sliders 18 at the aperture repress position Q3, the thickness Ea in the feed direction S 2 on the front side, that is, on the front side
The protrusion length adjusting piece 2 of each of the two sliders 18? b
The thickness Eb is made thicker. Inside the slider body 22 is a return bottle 31 and a return spring 3.
2 are arranged. A punch 7 for drawing and repressing the lower mold 6 shown in FIG. 6 is fixed to the lower mold 6, and a cylindrical wrinkle presser 30 disposed so as to surround the punch 7 It is said to be able to move up and down relative to type 6.

With the above configuration, the drawing repress of the substantially circular plate metal fitting is performed as follows. That is, to explain according to the process diagram of FIG. 7, first, in the feeding step of the first step, the strip material l is fed by one pitch of the inter-blank pitch P, and the blank 2a before the drawing repress is The repress will be sent to fiQ3. At this time, the connecting member 3a between the blank 2a and the blank 2b that has already been drawn and repressed in the previous stage (the connecting member 3a on the previous stage side) has already been moved to the pressing length T in the previous drawing and repressing process. It is assumed that the length A of the connecting member is extended from the length AI to the length A2.0 Then, in a second step, the upper mold 5 is
As the blank 2a descends, the blank 2a is pressed down by the wrinkle presser 30 of the lower mold 6 and the upper mold 5.Next, the lower surface of the blank 2a hits the punch 7 for drawing and repressing the lower mold 6, at the same time Pressing piece I6 of upper mold 5
The abutting surface 20 of the slider 18 touches the roller 19 of the slider 18 of the lower die 6, and the slider 18 advances. Here, the thickness Ea of the protrusion length adjusting piece 27a of each of the two rear sliders 18 among the four sliders 18 is larger than the thickness Ea of the protrusion length adjusting piece 27a of each of the two rear sliders 18. 2? Since the thickness Eb of b is thicker, the above 4.
The suppression surfaces 1B of each of the two sliders 18 simultaneously hit the bendable portions 28 of the corresponding connecting members 3.
Next, in the third pressing step, the upper die 5 is further lowered, and the blank 2a is drawn and repressed. At this time, the blank diameter R of the blank 2a is changed from the diameter R1 to the diameter R2.
It can be reduced to Therefore, the length B between the connecting points of the blank 2a is reduced from the length B1 to the length B2 by the reduced length ΔB. The blank 2 subjected to the drawing and repressing is indicated as a blank 2b in the figure. In this pressing step, as the upper die 5 descends, the slider 1 is advanced by the pushing piece 17 of the upper die 5.
The pressing surface 16 of 8 presses the flexible portion 28 of the connecting member 3 from the outer edge toward the center. Here, the outer edge and center refer to the outer edge and center of the strip material 1. Next, when the bendable portion 28 is pressed, the connecting member length A of the connecting member 3 is forcibly expanded. I am forced to do it. At this time, the connecting member length A of the connecting member 3a on the preceding stage side of the blank 2b is extended by an extension length ΔA from length A2 to length At, and the connecting member of the connecting member 3b on the rear stage side of the blank 2b is expanded by an extension length ΔA. length A is length A1
It is extended by an extension length ΔA from the length A2 to the length A2. That is, the length A of the connecting member 3a on the front side and the connecting member 3b on the rear side of the blank 2b as a whole is extended by the extension length 2ΔA. Here, the extension length ΔA is approximately determined by the extension length, ie, the pressing length T, from when the pressing surface 16 hits the bendable portion 28 when advancing G1 until the pressing ends. (See FIG. 3) This pressing length T can be adjusted by adjusting the protruding length of the pressing surface 16. Moreover, the protrusion length is determined by the protrusion length adjustment piece 2.
It is determined by the thickness E of 7. That is, by adjusting the thickness E of the protrusion length adjusting piece 27, the connecting member 3
The extension length ΔA of can be adjusted. Then, the protrusion length m1IJ is adjusted so that the reduced length ΔB of the length B between connecting points of the blank 2 and the overall extension length 2ΔA of the connecting member 3 are equal.
By adjusting the thickness E of the piece 27, even if the length A between the connection points of the blank 2 is reduced during the drawing repress, the pitch P between the blanks can be maintained at a predetermined pitch. Next, after the drawing repress step is completed, in a fourth step, the upper mold 5 is raised, and the slider 18 is moved backward G2 by the return pin 31 and the return spring 32. Below is the above 1st
The steps from the step to the fourth step are repeated to carry out sequential drawing and repressing.

Since the connecting member 3 is forcibly stretched as described above, the stretched connecting member 3 rarely returns to the state before being stretched during the feeding process of the strip material l. Therefore, it is easy to increase the accuracy when maintaining the pitch P between the blanks of the strip material 1 at a predetermined pitch, and in order to maintain the pitch P between the blanks of the strip material 1, side edges are provided as in the conventional method. Since this is not necessary, the overall radius of the strip material 1 can be made approximately equal to the blank diameter R1. Therefore, it is easy to reduce the amount of material required for the strip material 1 for 2.1 blanks, and therefore it is easy to improve the retention of the material in the product obtained by drawing and repressing.

Incidentally, the processes such as punching press and bending press other than the above-mentioned drawing and repressing process are substantially the same as the conventional ones, so detailed description thereof will be omitted.

In addition, in this example, we have described the drawing repress for manufacturing the approximately circular plate metal fittings used in the above-mentioned floppy disks.
The present invention is not limited to this example, and the present invention can be utilized when the size of the blank is reduced by the drawing repress. When the above-mentioned drawing repress is a multi-stage drawing repress, it is also preferable to utilize the present invention in each stage of drawing repress.

Here, the pressing surface reciprocating means is not limited to the push piece 17 and slider 18 shown in this example, but various pressing surface reciprocating means can be considered.

【effect] As detailed above, the present invention has the following effects.

According to the invention as claimed in claim 1, the connecting member of the strip material is pressed by a predetermined pressing length in the width direction by connecting the blanks in multiple stages with the connecting member, and thereby the connecting member is pushed by a predetermined extension length. By forcibly stretching, it is easy to improve the material yield of the drawn and repressed product, and it is also possible to increase the accuracy in maintaining the pitch between the blanks at a predetermined pitch.For progressive drawing and repressing. strip material can be provided.

Furthermore, according to the second aspect of the invention, it is possible to provide a pressing method suitable for progressively drawing and repressing the strip material according to the first aspect.

Furthermore, according to the third aspect of the invention, it is possible to provide a press mold suitable for realizing the pressing method of the second aspect using the strip material of the first aspect.

[Brief explanation of drawings]

The accompanying drawings show embodiments of the invention, and the 11i! l
! 3 to 3 show the strip material, FIG. 1 is a plan view, FIG. 2 is a side view, and FIG. 3 is a partially enlarged plan view of FIG. 1. Each figure from Fig. 4 to Fig. 6 shows the press die, Fig. 4 is a bottom view of the upper die, Fig. 5 is a plan view of the lower die, and Fig. 6 is shown along line x-x'' in Fig. 5. Figure 7 is a process diagram showing the pressing method.
3...Connection member, 4...Press mold, 7
...Ponchi, 8...Gui, 18.
...Press surface, 17...Push piece, 18.
...Slider, 28...Bendable part, A...
・・Connection member length, B・・Length between connection points, F・・・
・Connection point, G...Reciprocating movement, L...Width of strip material, P...Pitch between blanks. S: Indicates feeding direction, T: Indicates pressing length, respectively.

Claims (3)

[Claims] (1) A connecting member for connecting the front blank and the rear blank of the blanks to be progressively drawn and pressed, and for maintaining the inter-blank pitch between the center of the front blank and the center of the rear blank at a predetermined pitch. and in the strip material in which a plurality of blanks are connected in multiple stages in the feeding direction of the progressive drawing press; portion 28, and this bendable portion 28 has the above-mentioned width L.
By being pressed by a predetermined pressing length T from the convex side in the direction, the length A of the connecting member 3 in the feeding direction S
A strip material for a progressive drawing press, characterized in that the strip material is forcibly extended by a predetermined extension length ΔA. (2) A plurality of blanks are connected by a connecting member to connect the front blank and the rear blank of the blanks to be drawn and pressed in a progressive manner, and to maintain the inter-blank pitch between the center of the front blank and the rear blank at a predetermined pitch. In the pressing method, a strip material connected in multiple stages in the feeding direction is fed to a press die at the predetermined pitch, and a blank of the strip material sent to the press die is drawn and pressed; Then, the above-mentioned blank is drawn and pressed, and the length between the connection points between the connection point of the blank to be drawn and pressed with the connection member with the previous stage and the connection point with the rear stage is reduced, and the length between the connection points of the connection member is reduced. In order to extend the length of the connecting member along the feeding direction by a predetermined extension length, the flexible portion of the connecting member, which is convex in the width direction of the strip material, is pressed by a predetermined pressing length from the convex side. A pressing method for a progressive drawing press, characterized in that the connecting member is forcibly extended by the following steps, thereby making it easier to maintain the pitch between the blanks at a predetermined pitch. (3) A connecting member for connecting the front blank and the rear blank of the blanks to be progressively drawn and pressed, and for maintaining the inter-blank pitch between the center of the front blank and the center of the rear blank at a predetermined pitch. and a drawing punch for drawing and repressing the blank of the strip material while the strip material in which the plurality of blanks are connected in multiple stages along the feeding direction of the progressive drawing press is fed at a predetermined feeding pitch; In a press mold having a drawing die; of the connecting member 3 between the blank 2 which is drawn and pressed by the drawing punch 7 and the drawing die 8, and each of the blank 2 at the front stage and the blank 2 at the rear stage of this blank 2; Bendable portion 28 that is convex in the width L direction of the strip material 1
Pressing surface 1 for pressing from the convex side in the width L direction
8, and a pressing surface reciprocating means for causing the pressing surface 18 to reciprocate G in the width L direction so that the pressing surface 18 presses the flexible portion 28 by a predetermined pressing length T. Press mold for progressive drawing press.