JP2008168384A - Punch die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a punch die restraining punching flashes while securing the life of the punch die in punching a printed wiring board. <P>SOLUTION: In this punch die 11 used for punching a flexible printed wiring board 50A, corrugated indentations and projections 12 seen from a side are continuously formed on a bottom face of the punch die 11, and the indentations and projections 12 are provided diagonally in parallel seen from a bottom face across the entire bottom face. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a punch die, and more particularly, to a punch die used for punching a printed wiring board.

  Printed wiring boards used in electronic devices, especially in multilayer flexible printed wiring boards in which component mounting parts are connected to each other by cable parts, locations where the thickness is partially different between flexible cable parts and component mounting parts (For example, refer to Patent Document 1).

  An example of the process of punching the product outer shape with a general punch mold in such a flexible printed wiring board having different layer configurations will be described with reference to FIGS. FIG. 9 shows a state in which a plurality of identical circuit patterns are continuously formed on the flexible printed wiring board 50, and a product outer shape 51 indicated by a broken line is punched and separated by a punch die.

  FIG. 10 is an enlarged view of a portion A in FIG. 9, where FIG. 10A is a plan view, and FIG. 10B is a cross-sectional view taken along line BB in FIG. Each flexible printed wiring board 50A has an adhesive member 53 interposed between the first base film 52a and the second base film 52b. In the illustrated example, the upper and lower layers are configured, but a multilayer configuration in which a plurality of circuit patterns are arranged on the adhesive member 53 may be used. In the present embodiment, the circuit pattern is not shown for simplification.

  A product outer shape 51 of the flexible printed wiring board 50A is composed of three parts, and a component mounting part 55 having shield layers 54, 54 on the upper and lower sides and a component mounting part 56 having no shield layers on the upper and lower sides are connected by a cable part 57. Has been. The cable portion 57 is provided with shield layers 54 and 54 on the upper and lower sides, and a hollow portion 58 is provided between the upper and lower base films 52a and 52b.

  Here, reference numeral 59 denotes an area in which an opening for incorporating a device into the component mounting portion 56 is provided, and the opening 59 is also punched out with a punch die. Reference numeral 54b denotes a shield layer of an adjacent circuit.

  FIG. 11 shows a punching part, and a hatched part 60 is punched in one step in the outer part of the product outer shape 51, and the outer part of the punching part 60 becomes a discard part 61. Further, several connecting portions 62 are left between the punched portions 60 and 60. The connecting portion 62 is cut and removed when the product is divided into individual products after various processes in the flexible printed wiring board 50A are completed.

  12 shows a state where the flexible printed wiring board 50A is placed on the die 70, and is a cross-sectional view taken along the line CC in FIG. A punch die 71 is set above the die die 70, and the punch die 71 is lowered to punch a punching portion 60 shown in FIG.

  FIG. 13 shows a plan view of the product outer shape 51. The punching process will be described with reference to FIG. 13A. As shown in FIG. Cutting starts from a certain component mounting portion 55. The cable portion 57 is apparently the same thickness as the component mounting portion 55, but since there is a hollow portion 58, the cable portion 57 is pushed downward by the punch die 71, and the cable portion 57 starts cutting with a delay.

  Accordingly, as shown in FIG. 13B, when cutting of the component mounting portion 55 proceeds, cutting of the component mounting portion 56 without the shield layer starts next. Then, when the punch die 71 is further lowered and the cutting of the component mounting portion 55 and the component mounting portion 56 is finished, cutting proceeds from both sides of the cable portion 57, but as shown in FIG. If the traveling direction is deviated, punching burrs are generated.

  As a cause of the shift in the cutting direction, the cable portion 57 has a hollow portion 58, and as shown in FIG. 14, the cutting portion is deviated as the hollow portion 58 is bent.

  As a configuration for suppressing punching burrs by a punch die, a punching punch die is known in which a blade edge is formed in an acute shape so as to extend obliquely from the tip of the blade, and the blade edge is cut so as to contact with a time difference ( For example, see Patent Document 2).

A punching device is also known in which the punching punch (punch die) has a V-shaped or semi-elliptical cross section and the blade tip has a punching angle of less than 90 °, preferably 45 ° (see, for example, Patent Document 3). ).
Japanese Patent No. 3176858 JP-A-9-150399 Special table 2003-533362 gazette

  Like the printed wiring board described in Patent Document 1, the flexible printed wiring board having portions having different thicknesses between the flexible cable portion and the component mounting portion is a punch type as described in FIGS. When punching out, the hollow part of the cable part bends, so that the cutting direction is shifted and burrs are generated.

  The punching die described in Patent Document 2 is intended to improve punch sharpness and suppress punching burrs. However, when punching cable portions having different thicknesses, the punching die has a time difference. If hit, punching deviation will occur. In particular, the cable portion is required to be made of a material having good bending characteristics. If the cable portion formed of a soft material first hits the punched blade edge, a thread-like burr is likely to occur due to punching deviation. In addition, if there is an acute angle portion in the punch die edge, blade spillage is likely to occur and the life of the die is shortened.

  In the punching device described in Patent Document 3, the punching punch (punch die) has a V-shaped or semi-elliptical cross section. The occurrence of thread-like burrs due to the above cannot be suppressed, and if there is an acute angle at the tip, the life of the mold will be shortened. Further, since the scrap is pushed out only by the blade edge, if a highly flexible material is punched, the scrap may jump up to the upper part of the printed wiring board due to elastic repulsion. Furthermore, although the shape in which the blade edge is formed in a side view waveform is disclosed, in this case, the blade edge has a sharp portion, the mechanical strength is fragile, the blade spills easily, and the life is shortened. .

  Therefore, an object of the present invention is to provide a punch die that suppresses the occurrence of punching burrs while ensuring the life of the punch die in the punching process of a printed wiring board.

  The present invention has been proposed in order to achieve the above object, and the invention according to claim 1 is a punch die used for punching a printed wiring board, and the lower surface of the punch die is seen in a side view. Provided is a punch mold characterized in that uneven portions having inclined sides or curved sides of the same shape are continuously formed, and the uneven portions extend over the entire lower surface and are obliquely parallel in bottom view.

  According to this configuration, since the concave and convex portions having the same shape are continuously formed on the lower surface of the punch die in a side view, when the punch die is lowered and the convex portion of the concave and convex portions hits the printed wiring board, first, the printed wiring The plate is cut into broken lines. As the punch die is lowered, the cutting is pressed by the cutting edge so that the broken cutting portion is connected. Therefore, even if the cutting direction is shifted, cutting is performed such that the uncut portion between the broken-line-shaped cutting portions is torn, and the shift in the cutting direction is absorbed, and the generation of burrs can be prevented. In addition, since the concavo-convex portion is provided obliquely parallel to the bottom surface over the entire lower surface, the concavo-convex portion is in uniform contact with all sides regardless of the direction of the punching line. The effect appears.

  According to a second aspect of the present invention, there is provided the punch die according to the first aspect, wherein the uneven portion has a wave shape.

  According to this configuration, since the concavo-convex portion has a corrugated shape, cutting by pressing the blade edge is performed smoothly, and absorption of deviation in the cutting progress direction is also improved.

  In the present invention, an uneven part having the same shape, for example, a wave shape, is continuously formed on the lower surface of the punch mold in a side view, so that the printed wiring board is cut into a broken line and the cut part in the broken line is connected. Therefore, the occurrence of burrs can be prevented by absorbing the deviation of the cutting direction. Further, since the corrugated uneven portions are provided obliquely in parallel over the entire lower surface of the punch mold, it is possible to prevent the occurrence of burrs in any direction of the punching line. Further, the mechanical strength is ensured and the life of the mold can be maintained long. Further, since the scrap is pushed out over the entire lower surface of the punch mold, the scrap is surely dropped into the opening of the die mold, and the discharge performance of the scrap is improved.

  Hereinafter, the punch die according to the present invention will be described with reference to preferred embodiments. In the punching process of a printed wiring board, the present invention is used for the punching process of a printed wiring board in order to achieve the object of providing a punch mold that suppresses the occurrence of punching burrs while ensuring the life of the punch mold. The punch mold has a concave and convex portion having the same inclined side or curved side as viewed from the side, and is continuously formed on the lower surface of the punch die. Realized by providing diagonally parallel.

  FIG. 1 is a front view of the punch mold, FIG. 2 is a view taken along the arrow α-α in FIG. 1, and FIG. 3 is a view taken along the arrow β-β in FIG. In addition, since the product external shape 51 of the flexible printed wiring board 50 and each flexible printed wiring board 50A to be punched is exactly the same as the shape shown in FIG. 9 to FIG.

  As shown in FIGS. 1 to 3, the punch die 11 is set above the die die 10, and the punch die 11 is lowered to punch out the punched portion 60 of the flexible printed wiring board 50 </ b> A shown in FIG. 11. On the lower surface of the punch die 11, a concavo-convex portion 12 having an inclined side or a curved side having the same shape in a side view is continuously formed. In this embodiment, the concavo-convex portion 12 is formed in a corrugated shape having curved sides of the same shape, and the concavo-convex portion 12 is provided obliquely parallel to the bottom surface of the punch die over the entire bottom surface. .

  As shown in FIG. 3, if the concave portion 12a of the concave and convex portion 12 is represented by a broken line and the convex portion 12b is represented by a solid line, each side 11a of the punch die 11 in the X direction (left and right direction in FIG. 3) and the Y direction (vertical The concave portion 12a and the convex portion 12b are formed in parallel at an inclination angle of about 45 ° with respect to any of the sides 11b.

  In this way, by forming the concavo-convex portion 12 in an obliquely parallel view in the bottom view, the end surface shape of the concavo-convex portion 12 (in the present embodiment, the wave shape in either the X direction or the Y direction). Shape) appears evenly. The inclination angle of the uneven portion 12 with respect to the sides 11a and 11b is not necessarily 45 °, and may be any inclination angle such as 40 ° or 35 ° with respect to one side.

  FIG. 4 shows a state in which the flexible printed wiring board 50A is placed on the die mold 10, and a component mounting portion 55 having shield layers 54 and 54 on the upper and lower sides, and a component mounting portion 56 having no shield layer on the upper and lower sides. They are connected by a cable part 57. The outer portion of these punched portions 60 is a discarding portion 61.

  FIG. 5 is a plan view for explaining the punching process of the product outer shape 51, and FIG. 6 is an explanatory view showing a change in the cut portion. When the punch die 11 is lowered, as shown in FIG. 5A, the convex portion 12b of the concave and convex portion 12 formed on the lower surface of the punch die 11 is first a component having the thickest shield layer. Abutting on the mounting part 55, the cutting line L of the component mounting part 55 is pressed by the convex part 12b, and a part L1 of the cutting line L is cut into a broken line as shown in FIG. .

  As the punch die 11 descends, the projected line L is further pressed by the convex portion 12b, and as shown in FIG. 6 (b), it extends so that the broken-line-shaped cutting portions L1 are connected to each other. L2 is torn and cut. Then, as shown in FIG. 6 (c), the cutting portion in the broken line shape is connected, and the cutting is completed L3.

  As shown in FIG. 5B, when the cutting broken line of the component mounting portion 55 is connected and the cutting is completed, a part of the cable portion 57 starts to be cut and the cutting of the broken line proceeds. At the same time, there is no shield layer. Cutting of the component mounting unit 56 begins. The cutting of the cable part 57 and the cutting of the component mounting part 56 are performed so that the broken-line cutting parts L1 are connected to each other as shown in FIGS. The uncut portion L2 is torn and cut.

  As shown in FIG. 5 (c), the cable portion 57 is finally connected to each other by the progress of the cutting from the component mounting portion 55 side and the cutting from the component mounting portion 56 side. Cutting is complete.

  At this time, even when the traveling direction of the cutting L1 tends to shift due to the bending of the cable portion 57 or the like, as shown in FIG. 6 (d), the broken cutting L1 seeks a portion where the mechanical strength of the material is weak. Further, since the uncut portion L2 between the broken-line-shaped cut portions is cut so as to be torn, the shift in the cutting progress direction is absorbed and the generation of burrs can be prevented.

  FIG. 7 shows the dimensions of the concavo-convex portion 12, and according to the cutting experiment results, the depth of the concavo-convex portion 12 cannot be cut in a broken line shape at the cable portion 57 if the depth is less than 0.3 mm. , Burrs are likely to occur. On the other hand, when the depth is deeper than 0.8 mm, the height of the cutting edge of the punch die 11 is increased, so that the life of the punch die 11 is shortened. Therefore, the depth of the uneven portion 12 is preferably 0.3 to 0.8 mm.

  Further, regarding the pitch of the concavo-convex portion 12, if the pitch is shorter than 1.0 mm, the tip shape of the convex portion 12b is made more acute in order to ensure a depth of 0.3 mm. Become. On the other hand, if the pitch is longer than 2.0 mm, when the broken line-shaped cutting at the cable portion 57 proceeds from both sides, a deviation occurs in the cutting direction and a burr is generated. Therefore, the pitch of the concavo-convex portions 12 is preferably 1.0 to 2.0 mm.

  FIG. 8 shows a modification of the shape of the concavo-convex portion 12, FIG. 8A shows a mountain-shaped concavo-convex portion 13, and FIG. 8B shows a ridge-like concavo-convex portion 14 (reverse semicircular shape). It is provided. Any shape has the same effect as the wave-shaped uneven portion 12 described above.

  It should be noted that the present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

The front view of the punch type | mold which concerns on this invention. The alpha-alpha arrow line view of FIG. The beta-beta arrow line view of FIG. The front view of the state in which the flexible printed wiring board was mounted on the die type | mold. The top view explaining the punching process of a product external shape. Explanatory drawing which shows the change of a cutting part. Explanatory drawing which shows the dimension of an uneven | corrugated | grooved part of a punch type | mold. Explanatory drawing which shows the modification of the shape of a punch-shaped uneven | corrugated | grooved part. The top view of the flexible printed wiring board in which the some circuit pattern was formed. The A section enlarged view of FIG. Explanatory drawing which shows the location punched with a punch type | mold. The front view of the state which showed the prior art example and the flexible printed wiring board was mounted on the die type | mold. The top view which shows a prior art example and demonstrates the punching process of a product external shape. Sectional drawing of the cable part of the state which shows a prior art example and the hollow part 58 bent.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Die type | mold 11 Punch type | mold 12 Uneven part 12a Concave part 12b Convex part 13 Uneven part 14 Uneven part 50 Flexible printed wiring board 50A (individual) flexible printed wiring board 51 Product external shape 52a 1st film base 52b 2nd film base 53 Adhesive member 54 Shield layer 55 Component mounting part (with shield layer)
56 Component mounting part (no shield layer)
57 Cable part 58 Hollow part 59 Opening part 60 Punching part 61 Throwing part 62 Connection part

Claims (2)

  A punch die used for punching a printed wiring board, wherein concave and convex portions having an inclined side or a curved side having the same shape in a side view are continuously formed on the lower surface of the punch die, and the concave and convex portions are A punch mold characterized by being provided obliquely parallel to the bottom surface over the entire bottom surface.   2. The punch mold according to claim 1, wherein the uneven portion has a wave shape.

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