Snap button

A snap button is provided, which can function as both of a male snap and a female snap without accurate alignment or positioning two snap buttons to be engaged with each other. The snap button comprises a button body, wherein the button body includes a plurality of projections and a plurality of recesses, which are circumferentially alternately arranged. Each of the projections includes at least one salient and each of the recesses includes at least one protrusion. Each of the projections may be shaped as a horizontal cross-section thereof gradually decreases from the proximal end to the distal end. Further, the circumferential range of each recess is larger than that of each projection. The protrusion may have one or more cutouts, and the salient may be hemispherically shaped.

This application is a national stage application of PCT/JP2009/053211, which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a snap button used for clothes, bags and the like, more particularly, to a snap button which can function as both of a male snap and a female snap.

In general, a snap button is used as a pair of a male snap and a female snap, where the male snap has a projection and the female snap has a recess for detachably receiving the projection of the male snap. Therefore, between the male and the female snaps, steps of manufacture, inventory management, attachment to cloths, etc. are different. To improve this matter, Japanese Examined Utility-Model H06-31929 discloses a technology in which one sort of a snap button can be used as both of a male snap and a female snap. The snap button disclosed in the document includes a pair of male pieces and a pair of female pieces both of which project from a disk-shaped button body. In use, the pair of the male pieces of one of two same snap buttons are fitted between the pair of the female pieces of the other button.

In the snap button disclosed in the document, when the two snap buttons are engaged with each other, it is necessary not only to accurately align the axis of one of the two snap buttons with the axis of the other but also to adjust the circumferential positions of the two snap buttons so as to match the pair of the male pieces of one of the two snap buttons with the pair of the female pieces of the other. Therefore, the act of engaging the two snap buttons has to be performed very carefully. In addition, when the two snap buttons are attached to cloths, they have to be fixed in proper and accurate circumferential positions, which makes the work of attaching buttons to cloths difficult.

In view of the problems as mentioned above, an object of the present invention is to provide a snap button which can function as both of a male snap and a female snap without accurate alignment or positioning two snap buttons to be engaged with each other.[Patent document 1] Japanese Examined Utility-Model H06-31929

SUMMARY OF THE INVENTION

According to the present invention, there is provided a snap button made of resin which can function as both a male snap and a female snap to be used in a pair, comprising a plate-like button body; wherein the button body includes a plurality of projections projecting from a surface of the button body and a plurality of recesses recessed from the surface to detachably receive the projections of a separate and same snap button, the projections and the recesses being circumferentially alternately arranged with respect to the center of the button body; a circumferential range of each of the recesses is larger than that of each of the projections; each of the projections includes at least one salient protruding radially inward at a projecting end portion of each projection; and each of the recesses includes at least one protrusion protruding radially outward at a radially inner side of an opening of each recess to engage with the salient of each projection of the separate and same snap button when the recesses receives the projections, the opening being open on the surface of the button body.

The snap button according to the present invention is used as a pair of two same snap button. The two snap buttons are attached to clothes etc. using separate attaching members, and the projections and the recesses of one of the two snap buttons are engaged and disengaged with the recesses and the projections of the other snap button, respectively. In the present invention, the circumferential range of each recess is larger than that of the proximal end of each projection. The circumferential range of each projection is maximal at its proximal end. Therefore, when the projections of one of the two snap buttons are matched with the recesses of the other button, it is easy to position the top of each projection within the range of the opening of each recess, and it is unnecessary to strictly positioning circumferentially the two snap buttons when they are engaged with each other. The number of the projections provided in the snap button is preferably two, but it may be three or more, and the same is true of the recesses. Though the recess is recessed from the surface of the button body, the recess may be a bottomless through hole penetrating the button body. Though the shape of the button body is generally a circle or a polygon close to a circle, it may be a rectangle and the like. As described later, the projection is preferably projected from the surface of the button body (i.e., the proximal end of the projection) while a horizontal cross-section of the projection gradually decreases. However, not limited to this, the projection may be projected from its proximal end to its distal end with a uniform horizontal cross-section.

According to an embodiment of the present invention, each of the projections is projected from the surface of the button body while a horizontal cross-section of each projection gradually decreases.

As a result, each projection is tapered off from the proximal end to the distal end, which makes it easy to match each projection with each recess. Further, with the tapered projection, it is possible to secure a large cross-section of the projection at the proximal end, which can ensure the strength of the projection. A specific shape of the projection is, for example, as follows: That is, the projection may comprise a projection body having an inward face facing radially inward, an outward face facing radially outward, and bilateral side faces between the inward and outward faces; and the salient protruding from an upper end portion of the inward face of the projection body. Here, the outward face may be inclined as gradually closing to the inward face from the proximal end (base end) to the distal end (projecting end), and the bilateral side faces may be inclined so as to be gradually close to each other from the proximal end to the distal end. However, the shape of the projection is not limited to such a shape. By making the outward face and the bilateral side faces inclined, when matching the projection with recess, even if those inclined faces hit an edge etc. of the opening, the matching action would be smoothly done without obstruction due to the hit.

In the present invention, the radially inner side of the opening may have a chamfered portion. The slope of the chamfered portion can serve as a guide to introduce the projection into the recess, when the projection hits the chamfered portion on the way into the recess to match with.

Further, in the present invention, a radially outer face of the recess may be an inclined face inclined radially outward toward the surface of the button body. The radially outer slope of the recess can serve as a guide to introduce the projection, which hit the slope, into the recess while positioning the two snap buttons concentrically, when matching the projection with the recess.

In the present invention, the protrusion may have one or more cutouts. When the two snap buttons are engaged and disengaged, the salients of one of the snap buttons and the protrusions of the other come into contact with each other and elastically deformed, and then they are restored just after mutually passing over. The cutouts can make the protrusion more elastic or flexible, decreasing a force required for the engaging and disengaging actions between the two snap buttons. Besides, the cutouts may be slits and the like.

In the present invention, the salient may be hemispherically shaped. The hemispheric salient can more easily pass over the protrusion, decreasing a force required for the engaging and disengaging actions between the two snap buttons.

In the present invention, the circumferential range of each recess is larger than that of each projection, and therefore, when the projections of one of the two snap buttons are matched with the recesses of the other button, it is easy to position each projection with respect to each recess. Further, with the projection tapered off from the proximal end to the distal end, it is easier to position the projection with respect to the recess. Furthermore, with the one or more cutouts in the protrusion and the hemispheric salient, their slopes can serve as a guide to introduce the projection into the recess to match with, even if the axes of the two snap buttons are not aligned.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, preferred embodiments of the invention will be described with referring to the drawings.FIGS. 1 and 2are a perspective view and a plane view of a snap button1which can function as both of a male snap and a female snap according to an embodiment of the present invention.FIGS. 3 and 4are sectional views taken along line A-A and line B-B inFIG. 2, respectively. The snap button1, which is a molded resinous product, comprises a button body10having an octagonal disk-like shape, for example. To an upper surface11(the upper and lower directions are based onFIG. 4) of the button body10, concavity and convexity such as projections20and recesses30as described later are formed. The button body10includes a axially through hole12at the center portion thereof for receiving a post42of an attaching member40(seeFIG. 5etc.) as mentioned later when the snap button1is attached to a cloth. Above the hole12, there is provided a circular depression13concaved from the upper surface11for receiving a swaged upper end portion43′(seeFIG. 6etc.) of the post42of the attaching member40after having passed through the hole12. On the upper surface11of bottom body11, there are formed two projections20projecting upward from the surface11. The projections20are arranged radially outward from the depression13and oppositely in a diameter direction (hereinafter referred to as “the inter-projection diameter”) with the hole12placed between the projections20. Further, the bottom body11includes two recesses30recessed downward from the surface11, each of which is arranged alternately with and closely to each projection20circumferentially. Here, one projection20and one recess30occupy 180 degrees in the circumferential direction, and a circumferentially occupying range of one recess30is larger than that of one projection20as described later in detail.

Each of the projections20includes a projection body21and a salient26protruding radially inward from an upper end portion of an after-mentioned inward face22of the projection body21. The projection body21has a shape of which a horizontal cross-section as being generally sector form is gradually decreased from the base end (proximal end) abutting the surface11of the button body10to the upper projecting end (distal end). The projection body21has the inward face22facing radially inward which is a circularly curved concave surface having a generally trapezoidal form, an outward face23facing radially outward which is a circularly curved convex surface having a generally trapezoidal form, bilateral (in counterclockwise and clockwise directions circumferentially) side faces24,24having generally trapezoidal, an upper face25having generally rectangle form. The side faces24and the upper face25connect between the outlines of the inward and outward faces22and23. As can be seen fromFIG. 4etc., the inward face22is vertical to the horizontal direction or a horizontal plane, and the outward face23is inclined as gradually closing to the inward face22from the base end to the projecting end. Each side face24has the base end edge24′, which are in parallel to the inter-projection diameter. The bilateral side faces24are inclined so as to be gradually close to each other from the base end to the projecting end while maintaining being parallel to the inter-projection diameter. The salient26has a horizontally long and generally rectangular shape with its edge rounded. An upper face27of the salient26is flush with the upper face25of the projection body21. The upper face25of the projection body21and the upper face27of the salient26define a top25′ of the projection20.

Each of the recesses30has a sector form in a horizontal cross-section and is open on the surface11of the button body10as a sector-shaped opening31. Each recess30is defined by a radially inner side32extending along the circumferential direction, a radially outer side33, bilateral sides34,34connecting between the bilateral ends of the inner and outer sides32and33, and a horizontal bottom35. The outer side33is inclined radially outward from the bottom35to the opening31. Each bilateral side34is vertical to the horizontal direction and along a corresponding diameter direction. The inner side32includes a lower face32′ vertically rising from the bottom35and an upper protrusion36protruding radially outward with respect to the lower face32′. The protrusion36circumferentially extends all over the inner side32, and has an underside36cvertical to the lower face32′, a protruding end36bvertical to the underside36c, and a chamfered portion36achamfered obliquely between the protruding end36band the surface11of the button body10. The chamfered portion36aappears at the radially inner side of the opening31. The boundary between the surface11and the chamfered portion36ais positioned radially outward from the lower32′.

With referring toFIG. 2, the circumferential range of each recess30is set to be larger than the circumferential range of each projection20. More specifically, while the angle ranging between the bilateral sides34,34of one recess30is set to be approximately 100 degrees, the angle ranging between bilateral ends of the base end edge22′ of the inward face22, which is the circumferentially longest part in one projection20is set to be approximately 80 degrees. Each of the bilateral ends of the base end edge22′ of one projection20is tightly adjacent to one of the bilateral sides34,34of one of adjacent recesses30. The radial position of the inward face22of each projection20is at approximately the same as that of the protruding end36bof the protrusion36in each recess30. Further, the base edge23′ of the outward face23of each projection20is positioned at radially inward rather than the radially outer side arc31′ (the upper end edge of the outer side33) of the opening31in each recess30. Furthermore, the radially inward protruding height of the salient26from the inward face22is slightly smaller than the radially outward protruding height of the protrusion36from the lower face32′ in the recess30.

FIG. 5is a perspective view of a resin-made attaching member40to attach the snap button1to a cloth. The attaching member40is a conventional and includes a disk-like base41and a post42projecting from the base41along the axis of the member40. The upper end portion43of the post42is tapered off to the tip. With referring toFIG. 6, when the snap button1is attached to a cloth f using the attaching member40, after the post42pierces the cloth f from the opposite side to the snap button1and then passes through the hole12of the snap button1, the upper end portion43of the post42is swaged. As a result, the portion43is axially compressed and radially expanded to be a deformed or swaged portion43′. The swaged portion43′ is received in the depression13of the button body10and is unable to pass through the hole12.

FIGS. 6 and 7are sectional views illustrating respectively a state of two snap buttons1,1just before they are engaged and their engaged state, where the snap buttons1,1have been attached to their respective cloths f, f. The upper snap button1and the lower snap button1are fixed to the cloths f, f as being mutually displaced by about 90 degrees in the circumferential direction so that the projections20of the upper snap button1are matched with the recesses30of the lower snap button1and vice versa when they are engaged. However, in such a circumferential arrangement of the two snap button1,1, strict accuracy is not required because the circumferential range of the opening31of the recess30is remarkably larger than that of the top25′ of the projection20. Similarly, circumferential positioning of the upper and lower snap buttons1,1to engage them from theFIG. 6state can be roughly done. Further, the radial length of the opening31is longer than that of the top25′ of the projection20, and. Furthermore, the slope of the chamfered portion36aof the radially inner side32of the opening31and the slope of the radially outer side33of the recess30can serve as a guide to introduce the projection20into the recess30. Accordingly, the two snap buttons1,1can be smoothly engaged even if their respective axes are not accurately aligned or one axis inclines to the other axis. When the two snap buttons1,1are engaged and disengaged, the salients26of one of the snap buttons1,1and the protrusions36of the other come into contact with each other and elastically deformed, and then they are restored just after mutually passing over.FIG. 8shows a cross-sectional view taken along line C-C ofFIG. 7. In the engaged state, there is a little space in the recesses30, which allows the projections20to circumferentially displace somewhat within the recesses30. Accordingly, for example, when one cloth f on which one snap button1has been fixed is pulled and a force is exerted to cause the one snap button1to circumferentially displace relative to the other button1, it is possible to relieve the force while the one snap button1circumferentially moves somewhat relative to the other. Therefore, the snap buttons1,1are not easily disengaged.

FIG. 9shows a modified example of the upper protrusion of the recess30. The protrusion36′ includes a plurality of cutouts37(two cutouts37is shown inFIG. 9for example) circumferentially arranged therein. The cutouts37can make the protrusion36′ more elastically deformable against the salient26when the buttons1,1are engaged and disengaged.FIG. 10shows a modified example of the salient of the projection20. The salient26′ is hemispherically shaped protruding from the inward face22of the projection body21. The salient26′ can more easily pass over the protrusion36when two buttons1,1are engaged and disengaged.

As described above, with the snap buttons1according to the present invention, the engagement and disengagement between the two snap buttons1,1can be performed easily and smoothly since accurate alignment or positioning of the buttons in the circumferential direction and the axial direction is not required.

DESCRIPTION OF REFERENCE NUMBERS