EP0749706B1

EP0749706B1 - Rivet with washer and method of setting the same

Info

Publication number: EP0749706B1
Application number: EP19950304432
Authority: EP
Inventors: Kazuhiko Okazaki
Original assignee: YKK Snap Fasteners Japan Co Ltd
Current assignee: YKK Snap Fasteners Japan Co Ltd
Priority date: 1995-06-23
Filing date: 1995-06-23
Publication date: 2001-08-29
Anticipated expiration: 2015-06-23
Also published as: DE69522442D1; DE69522442T2; EP0749706A1

Description

This invention relates to a washered rivet for use as a reinforcement to a sewn part of clothing or the like and also to a use of the rivet for clothes.
DE-C-836 120 discloses a washer rivet combination to fix a button plate to a garment. The button plate not requiring holding by a die when attached. The washer securing the rivet has a flanged opening with the opening widening as it extends from the main plane of the washer.
GB-A-1 479 646 discloses a button with a disc-shaped main portion, a boss and a protruding narrow and point-shaped connection member of plastics material. Extending around the connection member the boss has a raised bevelled profile. The member is intended to be forced through a cloth so that the bevelled edge is brought into contact with one side of the cloth thus keeping the button head (main portion) of the button at a distance from the cloth surface. A round washer having a countersunk central through-hole is then brought into contact with the member so that the member extend through the through-hole.
Washered rivets are used in reinforcing the seams, pockets, and other sewn parts of heavy-duty clothes such as jeans and work clothes. Generally, as illustrated in FIG. 3, the washer 1 is an entirely flat, circular disk with a hole formed in the center. The washer of that shape is combined with a rivet 2 inserted through a cloth, and the end of the rivet shank protruding from the cloth and washer is pressed down by a die 3 to form a second head. The riveting has a shortcoming in that the scrap of the cloth punched by the rivet is left on the headed end 4 of the rivet 2 and affects the head contour unfavorably.
To overcome this shortcoming, it has been proposed, as shown in FIG. 4, to use a die 3' with an enlarged cavity 5, larger enough in diameter than the hole of the washer 1 to allow the scrap of the cloth 8 to fall from, and scatter around, the rivet end as the latter is pressed down. The proposed method presents another problem, however. The washer 1 being flat throughout, its inner peripheral portion 7 is deformed upwardly (as indicated by broken lines in FIG. 4) into the nonconstraining cavity space of the die 3'. The deformation not only mars the appearance but also can cause the rivet to come off the cloth.
The present invention, therefore, aims at providing a washered rivet which, when set on an article, forms a head sound in shape and appearance with the possibility of separating from the washer being very small.
The invention thus provides a washered rivet which is a combination of a washer whose inner peripheral portion around the center hole is depressed downwardly to a truncated conical shape toward the cloth with which the washer comes in contact and a rivet having a flat or more or less rounded shank end.
The headless end of the washered rivet of the invention is pressed down to form a second head for fastening purpose, using a die having a cavity larger in diameter than the hole of the washer.
FIG. 1 is a partly sectional side view of a die and a washered rivet embodying the present invention, immediately before setting on a cloth;
FIG. 2 is a side view of another form of rivet embodying the invention;
FIG. 3 is a partly sectional side view of a conventional die and washered rivet as set on a cloth; and
FIG. 4 is a partly sectional side view of another conventional die and washered rivet as set on a cloth; and
FIG. 5 is a cross sectional view of the washered rivet according to the present invention attached to a cloth.
Referring now to FIG. 1, a washered rivet 10 embodying the invention comprises a washer 20 whose inner peripheral portion 22 around the center hole is depressed to a truncated conical shape toward a cloth 40 with which it comes into contact and a rivet 30 having a rounded shank end 31. The washer and rivet are combined with the cloth in between and are joined by pressing down the rivet end by means of a die 50 whose cavity 51 has a diameter greater than that of the washer hole.
The washer 20 replaces the conventional flat disk, with its inner peripheral portion 22 around the center hole depressed to a truncated conical shape toward the cloth 40 with which it comes into contact.
The shank end of the rivet 30, as shown in FIG. 2, may be partly flat as at 31' in lieu of being rounded.
The die 50 that closes the rivet 30 of the washered rivet 10 over the washer 20 has a cavity 51 larger in diameter than the hole of the washer 20. The backing base located opposite to the die 50 and below the rivet 30 is not shown.
Pressing down the shank end of the rivet with the die 50 having the cavity 51 larger in diameter than the hole of the washer 20 applies upward (or outward) forces to the inner peripheral portion 22 of the washer 20 in the absence of constraint in the cavity of the die 50. Consequently, the inner peripheral portion 22 is forced upwardly. With the afore-described structure according to the invention, the inner peripheral portion is not deformed beyond the plane of the rest of the disk by the upward forces. The washer hole is thus reduced in diameter to improve the tightness of the rivet 30. There is no longer the prior art problem of loose rivet with a washer having a hole with an upwardly sloping periphery or with a head of poor appearance formed on the shank end. The downward pressing of the shank end 31 or 31' by the die 50 also causes the upper portion of the shank near the shank end 31 or 31' to bulge into a round head 33 larger in diameter than the washer hole, thereby securedly attaching the washer to the cloth as shown in Fig. 5.
If the amount of cloth scrap resulting from riveting were to be minimized, it would be desirable that the shank end of the rivet be sharply pointed. The pointing, however, requires secondary machining. In order to make the additional machining unnecessary, the present invention uses rivets with unpointed shank ends, such as rounded or flat ones in the embodiments described above. Even with an unpointed end, the rivet can be set using a die with a cavity greater in diameter than the washer hole to form a sound head; there occurs no such unwanted deformation that ordinarily results from pressing down with the cloth scrap deposited on the shank end.
The combination of rivet and washer of the structure and the method of setting the combination as described above in accordance with the present invention eliminate the undesirable deformation of the shank end or upward sloping of the periphery around the washer hole. Hence the invention precludes any adverse effect on the appearance of the headed end and its periphery or any separation of the rivet and washer from each other.
While what are believed today to be preferred embodiments of this invention have been illustrated and described herein, it will be obvious to those skilled in the art that various changes and modifications thereof are possible without departing from the invention as claimed.
The use of the term "disc" in this specification is not limited to circular plates.

Claims

A combination of a washer (20) and a rivet (30), the washer (20) comprising a disc with an outer peripheral edge and a centre hole extending from an outer face of the disc through to the inner face of the disc, the centre hole being defined by an inner peripheral portion (22) of the disc and being sized to accommodate a shank of a rivet (30), the inner face of the disc extending radially-inwardly from said outer peripheral edge to a preset distance from said inner peripheral portion (22) and the inner face extending radially-inwardly, and axially-towards-the-outer-face from said preset distance to said inner peripheral portion (22), characterised in that in unused condition the outer face of the disc extends axially in the same direction as the inner face.
The combination according to claim 1 wherein the inner face has a truncated cone cross-section in the region of the preset distance to the inner peripheral portion (22).
The combination according to claim 1 or claim 2, wherein the rivet (30) comprises a shank attached at one end to a head portion, the shank being, in use, inserted through the washer centre hole from the outer side of the washer (20).
A combination according to claim 3, wherein the shank has a round shank end or a flat shank end.
A use of a washered rivet (10) on a cloth (40) which comprises preparing a rivet (30) having a shank and a washer according to any one of claims 1 to 4, where the outer face of the washer is juxtaposed towards the cloth (40);

inserting the shank of said rivet (30) into the centre hole with the cloth (40) between the shank and the rivet (30);

pressing down the shank end of the rivet (30) over the washer (20) using a die (50) having a cavity (51) larger in diameter than the centre hole of the washer (20).
The use of a washered rivet (10) according to claim 5, wherein the shank end of the rivet (30) is round, or is flat.
Use of the combination according to claims 1 to 4, in fixing a rivet (30) to cloth (40) where the cloth (40) is sandwiched between the washer outer face and the rivet head.
Use of the combination according to any one of claims 1 to 4, in reinforcing cloth (40) or fixing pieces of cloth together, wherein said cloth is sandwiched between the outer face of the washer (20) and the rivet head.