Abstract
There is provided a cap, which is one part of a button fastener. The cap comprises a bottom and a circumferential side rising from an edge of the bottom. The cap is composed of an inner layer made of aluminum or aluminum alloy as a first material and an outer layer made of copper or copper alloy as a second material. The first and second layer are laminated on each other continuously across the bottom and the circumferential side. A Vickers hardness of the second material may be harder than a Vickers hardness of the first material. A tensile strength of the first material may be less than 260 N/mm2, and a tensile strength of the second material may be equal to or higher than 260 N/mm2.
Claims
1. A cap of a button or button fastener, comprising a bottom and a circumferential side rising from an edge of the bottom, wherein the cap is composed of an inner layer made of a first material and an outer layer made of a second material which is different from the first material, the inner layer and the outer layer being laminated on each other continuously across the bottom and the circumferential side rising from the bottom, wherein the first material is aluminum or aluminum alloy, and wherein the second material is copper, copper alloy, nickel alloy or zinc alloy.
2. The cap according to the claim 1, wherein a Vickers hardness of the second material is harder than a Vickers hardness of the first material.
3. The cap according to claim 2, wherein the Vickers hardness of the first material is 26 Hv or more and 95 Hv or less, and the Vickers hardness of the second material is 100 Hv or more and 175 Hv or less.
4. The cap according to claim 1, wherein a tensile strength of the first material is less than 260 N/mm2, and a tensile strength of the second material is equal to or higher than 260 N/mm2.
5. The cap according to the claim 4, wherein a tensile strength of the first material is equal to or less than 200 N/mm2.
6. A button group that includes a button group body and a cap which is attached to the button group body by swaging a circumferential side of the cap, wherein the cap comprises a bottom and a circumferential side rising from an edge of the bottom, wherein the cap is composed of an inner layer made of a first material and an outer layer made of a second material which is different from the first material, the inner layer facing the button group body, the outer layer being laminated on one surface of the inner layer which is opposite to the other surface facing the button group body, the inner layer and the outer layer being laminated on each other continuously across the bottom and the circumferential side rising from the bottom, wherein the first material is aluminum or aluminum alloy, and wherein the second material is copper, copper alloy, nickel alloy or zinc alloy.
7. A method for forming a button group that includes a button group body and a cap, comprising: a step of overlapping a first plate made of a first material and a second plate made of a second material on each other; a step of punching out the overlapped first and second plates and then molding it into a cup-shaped cap with the first plate placed on an inner side of the cap, the cap comprising a bottom and a circumferential side rising and extending from an edge of the bottom; and a step of swaging the circumferential side of the cap to the button group body to hold the button group body, wherein a Vickers hardness of the second material is harder than a Vickers hardness of the first material.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1 is a cross-sectional view that shows an embodiment of a button fastener that uses a cap according to the present invention;
(2) FIG. 2 is a cross-sectional view of a fastener body;
(3) FIG. 3 is a bottom view of the fastener body;
(4) FIG. 4 is an enlarged view of a vicinity of a circumferential side of the cap in FIG. 1;
(5) FIG. 5 is a process explanation view that shows a state in which a first plate and a second plate are overlapped with each other;
(6) FIG. 6 is a process explanation view that shows a state just before the cap is attached to the fastener body;
(7) FIG. 7 is a process explanation view that shows a state in which the circumferential side of the cap is swaged;
(8) FIG. 8 is a cross-sectional view that shows a state in which the button fastener in FIG. 1 is used to fix a female snap button to a cloth;
(9) FIG. 9 is a cross-sectional view that shows an embodiment of a button that uses the cap according to the present invention;
(10) FIG. 10 is an enlarged view of a vicinity of the circumferential side of the cap in FIG. 9; and
(11) FIG. 11 is a cross-sectional view that shows a state in which the button in FIG. 9 is fixed to the cloth.
DETAILED DESCRIPTION OF THE INVENTION
(12) Hereinafter, preferable embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to those embodiments, and modifications, etc. may be made to the embodiments within the scope of the claims and a range of equivalents. FIG. 1 is a cross-sectional view that shows an embodiment of a button fastener (hereafter, merely referred to as fastener) 10 as one example of a button group that uses a cap 20 according to the present invention. The fastener 10 has: an approximately circular, plate-like base 11; and a cylindrical post 12 that extends upward from the base 11 (an up-and-down direction is based on FIG. 1) concentrically with the base 11. The fastener 10 is intended to attach a button such as a female snap button 30 or the like to a cloth 1 as shown in FIG. 8 by swaging the post 12 that just has penetrated through the cloth 1. The fastener 10 is composed of only two parts, namely, a fastener body 13 as a button group body and the cap 20. The fastener body 13 is formed such as by drawing a metal plate, and makes the post 12 and a base core 14, which is an upper surface-side portion of the base 11. As the cap 20 is enlarged and shown in FIG. 4, its circumferential side 21 is swaged in C-shape and fixed to a radially outer end on the upper surface of the base core 14 of the fastener body 13. Accordingly, the cap 20 is attached to the base core 14 so as to cover the lower surface of the base core 14 from the lower side. Thereby, the cap 20 makes a lower surface-side portion of the base 11. Before the circumferential side 21 is swaged, as shown in FIG. 6, the cap 20 is in a cup-shape, which includes a circular plate-like bottom 22 and a circumferential side (namely, an outer circumferential side) 21 which extends upward from an edge (a radially outer end) of the bottom 22. A lower surface 22a of the cap 20 will become a front surface of the fastener 10. Hereafter, the lower surface 22a of the cap 20 is also referred to as the front surface 22a of the fastener 10. It can be said that the circumferential side 21 extends upward from the edge of the bottom 22.
(13) FIGS. 2 and 3 are a cross-sectional view and a bottom view of the fastener body 13. The base core 14 of the fastener body 13 has three openings 15, which are arranged at an equal interval in the circumferential direction and each of which has a home base shape. Each opening 15 is arranged so that a top 15a of the home base shape is oriented radially outward, and a bottom 15b of the home base shape, which is opposite to the top 15a is oriented radially inward. Each opening 15 is formed as follows: That is, the base core 14 is cut out in a home base shape except the bottom 15b, and then the cutout portion 15c is bent by 180 degrees to the lower surface-side of the base core 14. Thereby, the three cutout portions 15c almost close a lower opening of the post 12 of the fastener body 13. Also, the base core 14 of the fastener body 13 includes: a radially inner portion 14a; a radially outer portion 14b, which is located slightly lower than the radially inner portion 14a; and a connecting portion 14c connecting between the radially inner portion 14a and the radially outer portion 14b. Each cutout portion 15c bent from the opening 15 is located slightly higher than the lowest end of the radially outer portion 14b. Further, the top 15a of each opening 15 is within the range of the radially outer portion 14b, and the bottom 15b is within the range of the radially inner portion 14a.
(14) The cap 20 is composed of: an inner layer 20A that faces the base core 14 of the fastener body 13; and an outer layer 20B that is laminated on the entire lower surface of the inner layer 20A. Thus, the inner layer 20A and the outer layer 20B are laminated continuously across the bottom 22 and the circumferential side 21 of the cap 20. Here, the word continuity means that the inner layer 20A and the outer layer 20B are laminated over the whole area without any gaps. In this embodiment, the inner layer 20A is made of aluminum or aluminum alloy as one example of a first material, and the outer layer 20B is made of copper or copper alloy as one example of a second material. The thickness of the inner layer 20A is 0.2 mm as an example, and the thickness of the outer layer 20B is 0.15 mm as an example. Therefore, the thickness of the cap 20 is 0.35 mm. This thickness is approximately equal to that of a conventional cap made of only copper or copper alloy. Thus, in the cap 20, an amount of copper or copper alloy to be used, which is expensive relative to aluminum or aluminum alloy, can be reduced as compared with a conventional cap. In Table 1 shows a Vickers hardness, a tensile strength, a specific gravity and so on of the inner and outer layers 20A, 20B in this embodiment.
(15) TABLE-US-00001 TABLE 1 Thick- Vickers Tensile Specific Material ness Hardness Strength Gravity Inner Aluminum/ 0.2 mm 26 Hv~ 200 N/mm.sup.2 2.5 g/cm.sup.3~ Layer Aluminum 95 Hv or less 2.8 g/cm.sup.3 (20A) Alloy Outer Copper or 0.15 mm 100 Hv~ 200 N/mm.sup.2 8.4 g/cm.sup.3~ Layer Copper 175 Hv or more 8.9 g/cm.sup.3 (20B) Alloy
(16) In Table 1, the range of 26 Hv-95 Hv indicates the range between 26 Hv or more and 95 Hv or less, and the range of 100 Hv-175 Hv indicates the range of 100 Hv or more and 175 Hv or less. Also, with regard to the specific gravity, the range of 2.5 g/cm3-2.8 g/cm3) shows the range between 2.5 g/cm3 or more and 2.8 g/cm3 or less, and the range of 8.4 g/cm3-8.9 g/cm3 shows the range between 8.4 g/cm3 or more and 8.9 g/cm3 or less. In Table 1, regarding the Vickers hardness of the inner layer 20A and the Vickers hardness of the outer layer 20B, it can be understood that the lower limit value of the inner layer 20A is lower than the lower limit value of the outer layer 20B, and the upper limit value of the inner layer 20A is lower than the upper limit of the outer layer 20B. Also, with regard to the Vickers hardness of the outer layer 20B, 105 Hv or more is preferable. As can be seen from Table 1, the outer layer 20B is more rigid or harder in Vickers hardness than the inner layer 20A. Thereby, the front surface 22a of the fastener 10, which is defined by the outer layer 20B, is hard to scratch, similarly to a conventional cap made of only copper or copper alloy. Further, since the tensile strength of the inner layer 20A is 260 N/mm2 or less, a spring back in the inner layer 20A would be hard to occur when the circumferential side 21 of the cap 20 is curled, as compared with a case that a conventional cap made of only copper or copper alloy is curled. Thus, the cup 20 can surely hold the base core 14 as the circumferential side 21 is curled. More preferably, the tensile strength of the inner layer 20A is 200 N/mm2 or less. In this case, a spring back is further difficult to occur. Moreover, since the specific gravity of the inner layer 20A is between 2.5 and 2.8 g/cm3, the cap 20 is lighter than a conventional gap made of only copper or copper alloy, which has the same thickness as the cap 20. It is possible to obtain a cap that is lighter in weight than a conventional cap made of only copper or copper alloy by 30 to 40%. As examples of the first material whose hardness is between 26 Hv and 95 Hv, there are cited A1100-0 (Pure Aluminum), A1100-H24 (Pure Aluminum), A5052-0 (AlMg System), A5052-H34 (AlMg System), A5056-H112 (AlMg System), A5083-0 (AlMg System), A6063-T5 (AlMgSi System) and the like. Also, with regard to the second material whose hardness is between 100 Hv and 175 Hv, there are cited C2600-H (Brass C2600), C2680-H (Brass C2600), C4250-H (Tin Bearing Brass), C7540R-1/2H (Nickel Silver) and the like. Nickel silver is an alloy composed of Nickel silver, copper, zinc and nickel.
(17) Next, a process for manufacturing the button fastener 10 as mentioned above will be described. FIG. 5 shows a process for overlapping a band-like first plate 23, which becomes the inner layer 20A of the cap 20, and a band-like second plate 24, which becomes the outer layer 20B on each other. The first plate 23 is made of aluminum or aluminum alloy, and the second plate 24 is made of copper or copper alloy. The first and second plates 23, 24 are fed from supply rolls not shown, respectively, and then laminated on each other while being passed between a pair of compressing rollers 25. Then, caps are punched out from the first and second plates 23, 24 between a lower die 26 and an upper punch 27. Simultaneously, each of the caps is molded into a cup shape. That is, when the cap 20 is molded into the cup shape (refer to FIG. 6) having the bottom 22 and the circumferential side 21 as the cap 20 is punched out between the die 26 and the punch 27. In FIG. 6, a side in contact with a die 28 becomes the inner layer 20A, and a side in contact with the fastener body 13 becomes the outer layer 20B. With this molding operation, the inner layer 20A and the inner layer 20A are integrated into one unit without any use of adhesive agent and the like between them. However, in order to surely laminate the inner layer 20A and the outer layer 20B on each other, it is possible to use adhesive agent and the like between them or provide minute bumps and dips on the laminated surface(s) of the inner layer 20A or (and) the outer layer 20B. Next, the cup-shaped cap 20 is washed and then attached to the fastener body 13.
(18) FIG. 6 shows a state just before the cap 20 is attached to the fastener body 13. At this time, the cap 20 is placed on the die 28, and the circumferential side 21 of the cap 20 protrudes upward from the radially outer end of the bottom 22. Further, the fastener body 13 is put on the upper surface of the bottom 22 of the cap 20. A punch 29 is lowered from above to the cap 20 and the fastener body 13 in that state. The punch 29 has an annular concave 29b on a lower surface 29a of an annular lower part, and the concave 29b is recessed upward in a semi-circular shape. When the foregoing punch 29 is lowered, as enlarged and shown in FIG. 7, the circumferential side 21 of the cap 20 is swaged in C-shape radially inward along the concave 29b of the punch 29, and then fixed to the radially outer end on the upper surface of the base core 14 of the fastener body 13. Consequently, the cap 20 is attached to the fastener body 13. As mentioned above, with the inner layer 20A, a spring back is reduced when the circumferential side 21 of the cap 20 is swaged. Thereby reason, a rotation of the cap 20 with respect to the fastener body 13 over time will be hard to occur.
(19) FIG. 8 is a cross-sectional view that shows a state in which the button fastener 10 is used to fasten the female snap 30 as one example of a button, to the cloth 1. The female snap 30 has a circular bottom 31 and an annular side 32 that extends upward (based on FIG. 8) from a radially outer end of the bottom 31. Inside the annular side 32, a space 33 is defined for receiving a protrusion of a male snap that is not shown. The side 32 includes an expanded portion 34, which is expanded radially outward at its upper end. Inside the expanded portion 34, a spring 35 is disposed to assure of an engagement with a protrusion of a male snap. In the bottom 31 of the female snap 30, an opening 36 is formed. When the female snap 30 is fixed to the cloth 1, the post 12 of the fastener 10 is penetrated upward through the cloth 1 and then passed through the opening 36 of the female snap 30. After that, the post 12 is swaged by a punch not shown. Thereby, the female snap 30 is fixed to the cloth 1 as shown in FIG. 8.
(20) FIG. 9 is a cross-sectional view that shows an embodiment of a button 40 as one example of a button group using a cap 50 according to the present invention. The button 40 includes: a barrel 41 having a circular outer circumference; and a head 42 whose outer diameter expanding radially outward from the upper end (upper and lower are based on FIG. 9) of the barrel 41. The button 40 is composed of three parts, namely, a button body 43 as a button group body, a cap 50, and a reinforcement plate 44 disposed inside the head 42. The button body 43 is formed from a metal plate, and includes: a circumferential side 43a of the barrel 41; a bottom 43b of the barrel 41; a cylindrical part 45 that extends upward from the bottom 43b inside the circumferential side 43a; a head bottom 43c that extends radially outward from the upper end of the circumferential side 43a; and a head inner side 43d that extends upward from the radially outer end of the head bottom 43c. In the bottom 43b of the barrel 41, there is an opening 46 corresponding to the cylindrical part 45. In the cylindrical part 45, its diameter is gradually reduced upward, and the upper end of the cylindrical part 45 is spaced apart from the reinforcement plate 44. The upper end of the cylindrical part 45 is slightly expanded radially outward and serves as a locking portion 45a that locks a deformed top 62a of a shaft 62 of a button fastener 60 as described later. In the cap 50 of the button 40, its circumferential side 51 is swaged, from the outside, against the head inner side 43d of the button body 43 as enlarged and shown in FIG. 10. Thereby, the cap 50 is attached to the button body 43 and becomes an upper surface-side portion of the head 42. The upper surface of the cap 50 becomes the front surface of the button 40, on which a design such as characters, logos and the like is provided.
(21) The cap 50 comprises an inner layer 50A that faces the button body 43 and the reinforcement plate 44 and an outer layer 50B that is laminated on the whole area of the upper surface of the inner layer 50A. The inner layer 50A is made of aluminum or aluminum alloy as one example of the first material, and the outer layer 50B is made of copper or copper alloy as one example of the second material. The Vickers hardness, the tensile strength and the specific gravity of each of the inner and outer layer 50A, 50B are almost the same as those of the cap 20 in the first embodiment.
(22) FIG. 11 is a cross-sectional view that shows a state in which the button 40 is fixed to a cloth 2 using the button fastener 60. The button fastener 60 has an approximately circular, plate-like base 61 and a shaft 62 which extends upward from the base 61. Further, the button fastener 60 is composed of a fastener body 65 forming the shaft 62 and a base core 63 that is an inside reinforcement part of the base 61; and a base cap 64 that covers the base core 63 from a lower side. This base cap 64 is not a cap according to the present invention. When the button 40 is fixed to the cloth 2, the shaft 62 of the button fastener 60 is penetrated upward through the texture 2 and then passed through the cylindrical part 45 from the opening 46 of the button 40. Then, the shaft 62 is brought into contact with the reinforcement plate 44. Thereby, the top 62a of the shaft 62 is crushed and slightly expanded radially outward. The deformed top 62a of the shaft 62 cannot be passed through the top opening of the cylindrical part 45 and is consequently locked by the locking portion 45a. Thereby, the button 40 is fixed to the texture 2 as shown in FIG. 11.
DESCRIPTION OF REFERENCE NUMBERS
(23) 1, 2 cloth 10 button fastener 11 base 12 post 13 fastener body 14 base core 20, 50 cap 20A, 50A inner layer 20B, 50B outer layer 21, 51 circumferential side 22 bottom 30 female snap 40 button 41 barrel 42 head 43 button body 60 button fastener
