CN113263108A

CN113263108A - Progressive press working method

Info

Publication number: CN113263108A
Application number: CN202011425306.3A
Authority: CN
Inventors: 月冈敏幸
Original assignee: Apic Yamada Corp
Current assignee: Apic Yamada Corp
Priority date: 2020-02-17
Filing date: 2020-12-09
Publication date: 2021-08-17
Anticipated expiration: 2040-12-09
Also published as: JP7136821B2; CN113263108B; JP2021126695A

Abstract

The invention provides a progressive press working method applicable to amorphous foils. The method performs progressive press working on a metal foil, the metal foil is an amorphous foil (10), the amorphous foil (10) comprises a flange part (16) at the opening end part of a guide hole (15), and the thickness (t1) of the flange part (16) is thinner than the thickness (t0) of the peripheral area (14) of the guide hole (15).

Description

Progressive press working method

Technical Field

The invention relates to a progressive press working method of metal foil.

Background

In the progressive press working, a guide hole is formed in a band-shaped material, and a guide pin of a die is inserted into the guide hole to position the material and the die. If the strength of the guide hole is low and the guide hole deforms, the mold and the material cannot be accurately positioned, and therefore it is desirable to suppress the deformation of the guide hole. In order to suppress deformation of the guide hole, for example, it has been proposed to form a flange portion at an opening end portion of the guide hole by burring to increase a contact area between the material and the guide pin (see, for example, patent document 1).

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent application laid-open No. Hei 4-17929

Disclosure of Invention

[ problems to be solved by the invention ]

However, in the conventional structure as described in patent document 1, for example, it is sometimes difficult to form a guide hole having sufficient strength in a thin and hard metal foil. Accordingly, an object of the present invention is to provide a progressive press working method capable of improving the positional accuracy by securing the strength of a guide hole.

[ means for solving problems ]

A progressive press (transfer press) processing method according to an embodiment of the present invention is a method of performing progressive press processing on a metal foil, the metal foil being an amorphous foil, the amorphous foil including a flange portion at an opening end portion of a guide (pilot) hole, a plate thickness of the flange portion being thinner than a plate thickness of a peripheral region of the guide hole.

According to this aspect, by configuring the flange portion to have a plate thickness thinner than the plate thickness of the peripheral region of the guide hole, the guide hole including the flange portion can be formed even with a thin and brittle amorphous foil material. The periphery of the guide hole protrudes in the thickness direction of the amorphous foil, and the strength of the guide hole is increased. Further, the contact area between the amorphous foil and the guide pin is increased. Previously, it has not been thought at all to reinforce the guide hole by processing in such a manner that a thin and hard amorphous foil which is not suitable for plastic processing is protruded. According to this idea, deformation of the guide hole can be suppressed, and therefore, progressive press working can be applied to the amorphous foil.

In the above aspect, the forming of the guide hole preferably includes a drawing process of the flange portion while a burring process of the amorphous foil is performed.

According to this aspect, the guide hole including the flange portion can be formed in the amorphous foil as appropriate.

In the above aspect, the thickness of the front end portion of the flange portion is preferably 0.7 times or more and 0.9 times or less the thickness of the peripheral region.

In the above aspect, the thickness of the peripheral region may be 15 μm or more and 40 μm or less.

Even an amorphous foil material that is as thin and brittle as the above-described form can be subjected to progressive press working in the above-described form.

In the above aspect, the vickers hardness of the amorphous foil may be 700 or more and 900 or less.

Even an amorphous foil material that is as hard and brittle as the above-described form can be subjected to progressive press working in the above-described form.

[ Effect of the invention ]

According to the invention, a progressive press working method applicable to amorphous foils can be provided.

Drawings

Fig. 1 is a sectional view showing an example of a die used for progressive press working according to an embodiment of the present invention.

Fig. 2 is a plan view showing an example of the amorphous foil shown in fig. 1.

Fig. 3 is an enlarged cross-sectional view of the pilot hole shown in fig. 2.

Fig. 4 is a sectional view illustrating a step of forming a lower hole for burring.

Fig. 5 is a sectional view illustrating a step of drawing the flange portion while performing the burring.

[ description of symbols ]

1: die set

2: punch handle

3: die holder

4: outer guide rail

10: amorphous foil

14: peripheral region

15: guide hole

16: flange part

17: lower hole

20: upper die

21: lining plate

22: punch head plate

23: stripper plate

24. 24A, 24B: punch head

25: guide pin

30: lower die

31: lining plate

32: form panel

34. 34A, 34B: mould insert

h: height of flange part

t 0: thickness of peripheral region

t 1: thickness of flange

t 2: drawing gap

Detailed Description

Preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same or similar components. One of the features of the progressive press working method according to an embodiment of the present invention is: and carrying out flanging processing and drawing processing on the amorphous foil.

For example, when a soft material such as a copper alloy or an iron-based alloy used for the lead frame is subjected to burring, the material extends to, for example, about 0.7 times the thickness of the plate, and the flange portion is less likely to be broken. Since the amorphous foil is hard and hard to stretch, it is considered that the flange portion is easily broken and the burring is difficult. The amorphous foil is not limited to the burring process and is not suitable for the plastic working. Therefore, it is considered that the ironing work in which the flanging work is performed in combination with the drawing work is more complicated than the plastic working, and is more disadvantageous for the amorphous foil.

The invention is based on the following novel insights: by using the drawing process together with the flanging process, the flange portion is less likely to be broken even if the amorphous foil is used. The present invention will be described in detail below with reference to the drawings.

Fig. 1 is a sectional view showing an example of a die (progressive die) 1 used for progressive press working according to an embodiment of the present invention. In the illustrated example, the mold 1 is configured as a mold with a mold set, and main plates (a lining plate 21, a lining plate 31, a punch plate 22, a stripper plate 23, a die plate 32, and the like) are fixed to the inner sides of upper and lower mold set plates (a punch holder 2, a die holder 3) positioned by guide columns (outer guide rails 4).

In the following description, the various plates and their components fixed to the punch holder 2 are collectively referred to as an upper die 20, and the various plates and their components fixed to the die holder 3 are collectively referred to as a lower die 30. The structure of the mold 1 is not limited to the illustrated example, and an existing structure can be appropriately selected.

Various punches 24 and guide pins 25 for performing processes such as punching, bending, and drawing are fixed to a punch plate 22 included in the upper die 20. A die insert 24 and the like in which a receiving hole of the punch 24 is formed are fixed to a die plate 32 included in the lower die 30. The die insert 24 may be fixed to the backing plate 31 instead of the die plate 32. In this case, the template 32 may also be omitted. The stripper plate 23 guides the punch 24 and presses the material to be press-worked into the die insert 24. The liner plate 21 and the liner plate 31 bear the load of the punch 24 or the die insert 34 to suppress the deformation of the die set.

One of the features of the progressive press working method according to an embodiment of the present invention is: the material to be subjected to the press working is an amorphous foil 10. The amorphous foil 10 is, for example, a metal foil of an amorphous metal material containing iron as a main component. The amorphous foil 10 may contain other elements such as silicon and boron in addition to iron as a main component. If the physical properties are similar, the metal foil may be an amorphous metal material containing iron as a main component.

The amorphous foil 10 is produced according to Japanese Industrial Standards (JIS) Z2244: 2009 has a vickers hardness of about 800 (700 to 900 inclusive), and is hard and brittle as compared with a stainless steel foil material or the like, and therefore is not suitable for plastic working. The thickness t0 of the amorphous foil 10 before the press working is, for example, 15 μm or more and 40 μm or less. In the illustrated example, the plate thickness t0 is 25 μm. Since the guide hole 15 is easily deformed in the amorphous foil 10 having the thickness t0 as described above, progressive press working cannot be applied to the conventional method.

Fig. 2 is a plan view showing an example of the amorphous foil 10 shown in fig. 1. In the illustrated example, a thin plate for a stator core of a motor, which is a press-worked product, is worked. The illustrated thin plates can be laminated to form a stator core. The stator core in which the amorphous foil 10 is laminated can constitute a high-efficiency motor because the current (iron loss) flowing inside the core is as small as 1/10 for normal iron.

The press-formed product manufactured according to the present embodiment is not limited to the illustrated example, and may be, for example, a thin plate constituting a rotor core of a motor or a thin plate constituting a laminated core of a static induction device such as a transformer. The press-formed product suitable for the physical properties of the amorphous foil 10 can be selected as appropriate.

The guide pins 25 are used to position the semi-finished article through a series of pressing operations, which are included in progressive pressing operations. The material subjected to the press working is formed with a guide hole 15 for inserting the guide pin 25 by the first or second press working. The press working of the guide hole 25 will be described below with reference to fig. 4 and 5. As shown in fig. 2, a plurality of guide holes 15 are formed at equal intervals along the longitudinal direction of the strip-shaped amorphous foil 10.

Fig. 3 is an enlarged cross-sectional view of the guide hole 15 shown in fig. 2. The diameter of the guide hole 15 is, for example, about 1.5mm to 3.0 mm. The guide hole 15 includes a flange portion 16 at an open end thereof. Here, the flange portion 16 is a portion of a standing edge formed by a process such as a burring process (hole flanging process). The height h of the flange portion 16 can be adjusted according to the size of the hole 17 and the degree of drawing, which will be described later. In the illustrated example, the height h of the flange portion 16 is about 4 times the plate thickness t0 of the peripheral region 14.

At the periphery of the guide hole 15, a substantially undeformed peripheral region 14 of the amorphous foil 10 is demarcated. The thickness t0 of the peripheral region 14 is substantially the same as the thickness of the amorphous foil 10 before the press working, and is 25 μm, for example. The flange portion 16 formed at the opening end of the guide hole 15 has a slightly reduced plate thickness as it goes toward the front end. The front end portion including the front end of the flange portion 16 and the vicinity thereof is formed thinner than the plate thickness t0 of the peripheral region 14 of the guide hole 15.

The plate thickness t1 of the flange portion 16 at the tip end is preferably 0.7 times or more and 0.9 times or less the plate thickness t0 of the peripheral region 14. In the illustrated example, the plate thickness t1 of the tip end portion of the flange portion 16 is 0.8 times the plate thickness t0 of the peripheral region 14. The portion measured as the tip portion is, for example, a portion shifted by 10% of the height h of the flange portion 16 from the tip of the flange portion 16 toward the base end side.

Fig. 4 is a sectional view illustrating a step of forming the lower hole 17 for burring, and fig. 5 is a sectional view illustrating a step of drawing the flange portion while burring. As shown in fig. 4 and 5, if the punch 24A for performing the press working of the lower hole 17 and the punch 24B for performing the burring are independent of each other, the guide hole 15 having excellent machining accuracy can be formed as compared with the case where the press working and the burring of the lower hole 17 are performed by the same punch. Further, the lower hole 17 can be pressed and flanged by the same punch. In the example shown, the diameter of the lower hole 17 is 2.300mm, and the diameter of the guide hole 15 is 2.510 mm.

As described above, by drawing the flange portion while performing the burring, the guide hole 15 in which the flange portion 16 is not easily broken can be formed even in the amorphous foil 10. As shown in fig. 5, the amorphous foil 10 that is pushed into the receiving hole of the die insert block 34 by the punch 24B that performs the burring is drawn by the outer peripheral surface of the punch 24B and the inner peripheral surface of the receiving hole of the die insert block 34.

The degree of drawing can be arbitrarily adjusted according to the clearance t2 between the punch 24B and the die insert 34. As described above, the plate thickness t1 of the tip end portion of the flange portion 16 is preferably 0.7 times or more and 0.9 times or less the plate thickness t0 of the peripheral region 14. If the plate thickness t1 of the tip end portion of the flange portion 16 is less than 0.7 times the plate thickness t0 of the peripheral region 14, the amount of deformation due to drawing work becomes excessively large, and the flange portion 16 is likely to break. If the plate thickness t1 of the tip end portion of the flange portion 16 exceeds the plate thickness t0 of the peripheral region 14 by 0.9 times, the drawing work is insufficient, and therefore the flange portion 16 is easily broken.

According to the progressive press working method of the present embodiment, the flange portion 16 that is not easily broken is formed, and the progressive press working method can be applied to the amorphous foil 10.

The above-described embodiments are intended to facilitate understanding of the present invention, and are not intended to be construed as limiting the present invention. The elements included in the embodiments, their arrangement, materials, conditions, shapes, sizes, and the like are not limited to the examples, and can be appropriately changed. In addition, the structures shown in different embodiments can be partially replaced with each other or combined with each other.

Claims

1. A progressive press working method for metal foil, and

the metal foil is an amorphous foil material,

the amorphous foil comprises a flange part at the opening end part of the guide hole, and

the flange portion has a plate thickness smaller than a plate thickness of a peripheral region of the guide hole.

2. The progressive press working method according to claim 1, wherein

The step of forming the guide hole includes drawing the flange portion while flanging the amorphous foil.

3. The progressive press working method according to claim 1 or 2, wherein

The thickness of the front end of the flange portion is 0.7 times or more and 0.9 times or less the thickness of the peripheral region.

4. The progressive press working method according to claim 1 or 2, wherein

The thickness of the peripheral region is 15 μm or more and 40 μm or less.

5. The progressive press working method according to claim 1 or 2, wherein

The Vickers hardness of the amorphous foil is 700 to 900.