Patent Description:
Wristbands are used in a variety of situations. For example, wristbands can be used at events to authorize, locate, and/or identify participants at the event. Additionally, wristbands are ubiquitous in medical facilities as an identification and tracking device for patients undergoing medical care.

Most wristbands include a securing feature such as an adhesive section or a clasp and, after a loop has been formed, the securing feature keeps the wristband around the person wearing it. Such securing features can be used to adjust the length of the wristband to accommodate different tethering conditions (for example, for attachment to a large adult wrist versus a small child wrist) and, in many cases, to create a non-reversible connection to prevent non-destructive removal of the band, which also renders the identification device tamper-proof.

Clasps are extremely valuable as securing features as they enable the comfortable wearing using pre-indexed positions that are easy to install. Adhesive, by contrast, is less expensive to manufacture, but requires some placement skill to align and can lead to exposed adhesive that sticks to skin or hair and can make wearing uncomfortable and removal painful.

One complicating factor for the design of clasps is their assembly and insertion into wristband forms. This is done out of convenience and simplicity, but adds to the expense of manufacturing as nearly all clasps have a male and female or stud and socket type design. These two separate articles require separate sets of tooling for molds and insertion and often need to be carefully sorted during the manufacturing process.

Further prior art can be found in <CIT>, <CIT>, <CIT> and <CIT>.

The invention is set out in the pending set of claims.

An improved and novel clasp assembly with interlocking engagement is disclosed herein for a wristband that is formable into a loop. The clasp assembly can aid in keeping the wristband in a constant loop around the person wearing the wristband, can be simple in construction, and can prohibit non-destructive removal.

Of particular advantage is that the clasp assembly is designed to have two identical half sections instead of, for example, a male and female section or otherwise differentiated half sections. By having identical half sections, only a single type of half section needs to be produced for the clasp assembly instead of two unique half sections. This can save production costs by not requiring two sets of tooling for injection molding of the clasp portions. Still further, any possibility of mistake during the assembly of the half sections to a wristband can be avoided since, without unique half sections, there is no requirement that exactly one of each type of half section for the clasp assembly needs to be installed in a single wristband.

According to one aspect, a clasp assembly is provided which includes a pair of identical half sections configured to be coupled together. Each half section includes one or more deformable features that are designed to deform during closure to create an interlocking engagement between each half section and in which the one or more deformable features are posts extending from a base of the respective half section, the posts having a wedge shape with a tooth at the distal end with the tooth having a stop surface facing the base; wherein each of the pair of identical half sections has discrete rotational symmetry; wherein, after interlocking engagement, the stop surface of a post on one half section contacts the stop surface of a post on the other half section such that the pair of identical half sections are not completely axially separable without permanent mechanical destruction of the one or more deformable features; wherein the interlocking engagement is created between the teeth at the stop surfaces.

After interlocking engagement, the pair of identical half sections is not completely axially separable without permanent mechanical destruction of the one or more deformable features.

The clasp assembly has interlocking projections with teeth. The pair of identical half sections includes a base and the one or more deformable features is a plurality of posts extending axially from the base. Each of the posts of the identical half sections has a distal end away from the base including a tooth that radially projects from the post in which the tooth include a stop surface facing the base. The teeth of the posts have a wedge-like shape. The teeth further include tapered surfaces on angular ends thereof that narrow as the teeth extend towards the distal end of the respective post. In such a design, when the posts of the pair of half sections are axially brought together to engage the teeth of the posts together, the tapered surfaces on angular ends of the posts on each of the half sections may contact one another and effectuate the elastic deformation of the posts to permit the teeth of the posts to pass by one another until the stop surfaces of one of the half sections has axially passed the stop surfaces of the other one of the half sections, and the posts return to a non-deformed state which thereby creates an interlocking engagement between the posts on each of the half sections at the stop surfaces. It is contemplated that, in this form, each of the stop surfaces may have a corresponding angular extent between angular ends of the respective stop surface and the total summed amount of the angular extents of all of the plurality of stop surfaces on one of the half sections may exceed <NUM> degrees. This creates assured angular overlap between the stop surfaces of the pair of half sections with one another when the posts of the half sections are brought together in interlocking engagement.

In another embodiment which does not fall into the scope of the present invention, an alternative toothed structure is provided in which the base may include cutouts in which the teeth of the other half section are received. As with the first type of toothed structure, the pair of identical half sections may include a base and the one or more deformable features may be a plurality of posts extending axially from the base. In this form instead of teeth engaging with other teeth, the base can include a plurality of cutouts spaced about a peripheral edge of the base and, when the pair of half sections are axially brought together, the plurality of posts may elastically deform over a distance of axial travel during joining until the plurality of posts snap back to engage the plurality of cutouts on the periphery of the base and restrict axial separation of the pair of half sections. The plurality of posts may elastically deform outward due to an engagement of an axially-inclined surface of each respective post on one of the pair of half sections with the base (or an edge or surface thereof) on the other of the pair of half sections. Each of the posts may include a stop surface facing the base of the half section to which the posts belong and, when the pair of half sections are axially brought together to cause engagement of the plurality of posts with the plurality of cutouts, each stop surface engages an oppositely facing surface of a corresponding cutout to restrict the axial separation of the pair of half sections.

In another embodiment which does not fall into the scope of the present invention, the deformable features may have include various segments with frustospherical concave and convex portions that can be joined together reminiscent of a ball and socket type joint. Again, the pair of identical half sections may include a base with the one or more deformable features being a plurality of posts extending axially from the base. At least one of the plurality of posts may include an axially-facing concave surface (that is, axially-facing in that it faces in a radial direction facing the central axis as opposed to away from the axis) and at least one of the plurality of posts may include an outwardly-facing convex surface. The axially-facing concave surfaces are configured for interlocking engagement with the outwardly-facing convex surfaces when the pair of half sections are axially brought together. The axially-facing concave surfaces and the outwardly-facing convex surfaces may be, for example, frustospherical surfaces or elongated versions thereof. The number of the axially-facing concave surfaces may match the number of the outwardly-facing convex surfaces. In such forms, when the plurality of posts of the pair of half sections are axially brought together to engage the outwardly-facing convex surfaces of the posts with the axially-facing concave surfaces of the posts, the outwardly-facing convex surfaces of the posts on each of the half sections may contact the axially-facing concave surfaces of the posts and effectuate the elastic deformation of the posts to permit the outwardly-facing convex surfaces of the posts to pass by the distal ends of the posts having the axially-facing concave surfaces until the outwardly-facing convex surfaces reach or approach the proximal end of the axially-facing concave surface. Once there, the posts may return to a non-deformed state to create an interlocking engagement between the posts on one of the half sections at the outwardly-facing convex surfaces and the axially-facing concave surface of the posts on the other one of the half sections.

In another embodiment which does not fall into the scope of the present invention, yet another mechanical type of interlock is provided in which balls or heads on the end of posts are plugged into corresponding depressions on the opposing base. Again, the pair of identical half sections may include a base with the one or more deformable features being a plurality of posts extending axially from the base. At least one of the plurality of posts may have a ball-shaped surface and the base may further comprises a plurality of socket depressions that are configured to interlock with the ball shaped surfaces of the posts. The number of the ball-shaped surfaces may match the number of socket depressions. When the plurality of posts of the pair of half sections are axially brought together to engage the ball-shaped surfaces of the posts with the socket depressions, the ball-shaped surfaces of the posts on each of the half sections may contact with the socket depressions and effectuate the elastic deformation to seat the ball-shaped surfaces of the posts in the socket depressions thereby creating an interlocking engagement between the posts on one of the half sections at the ball-shaped surface and the socket depressions on the base of the other half section.

In some forms, the pair of half sections may each be an integrally formed plastic component.

According to another aspect, a wristband is provided including any of the aforementioned clasp assemblies described above or herein. In some forms, the wristband can include a band formable into a loop including the clasp assembly of the types described above and herein. It is also contemplated that this clasp assembly could also be used in other products (i.e., other than wristbands) in which non-reversible clasp attachment is desired.

These and still other advantages of the invention will be apparent from the detailed description and drawings. What follows is merely a description of some preferred embodiments of the present invention. To assess the full scope of the invention the claims should be looked to as these preferred embodiments are not intended to be the only embodiments within the scope of the claims.

Before any embodiments of the invention are explained in detail, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention.

Some of the discussion below describes a clasp assembly with an interlocking arrangement for a band that is formable into a loop and secured by the clasp assembly. While the discussion herein primarily discusses wristbands, the context and particulars of this discussion are presented as examples only and other embodiments are contemplated as falling within the scope of this disclosure. For example, embodiments of the disclosed clasp assemblies can include a variety of applications apart from those specifically illustrated with respect to wrist bands including but not limited to ankle bands (such as for infants), medical bands, bands for events such as concerts, straps for attachment around an object, and so forth. Still further, embodiments of the disclosed invention can be constructed from a variety of differently-shaped components that are assembled in various configurations including by use of different numbers of mating features than those depicted, only some of which embodiment will be described herein.

As used herein, the terms "deform" and "deformable" refer to any distortion of shape or form from an initial shape or form of a component. Such distortion may be temporary in nature (as in elastic deformation) or permanent in nature (as in plastic deformation). It is contemplated that, when a component is described as being "deformed" to create engagement between clasp sections herein, that that such deformation could involve a change from an initial un-deformed state to a deformed state. Depending on the design and mode of clasp operation, the component could remain in that deformed state to create engagement or could involve a subsequent return from that deformed state back towards or to its initial un-deformed state with such return being in full or only in part to create engagement.

Looking first at <FIG> illustrates an exploded view of an exemplary "toothed engagement" style clasp assembly <NUM> according to one embodiment. The clasp assembly <NUM> is designed to be affixed to a wristband, allowing the wristband to be formed into to loop around the wrist of the person wearing the wristband using the clasp assembly <NUM>. Such a wristband - albeit without the newly disclosed clasp assembly - can be found, for example, in <CIT>.

The clasp assembly <NUM> includes a pair of half sections <NUM> that, as illustrated, are identical to one another. Each half section <NUM> can be an integrally formed unitary structure, for example, formed by plastic injection molding. By being formed from plastic, thin walls of the parts - such as the posts <NUM> that will be described in greater detail below - may be elastically deformable or able to temporarily bend or deflect.

Each of the pair of half sections <NUM> includes a base <NUM>, which as illustrated can be generally disc-shaped. However, the base <NUM> can be in various other forms or shapes. For example, the base <NUM> could be rectangular, square, triangular or other polygonal or non-polygonal shape. The shape of the base <NUM> may be altered in some cases, based on the shape of the wristband to which the clasp assembly <NUM> is attached.

The base <NUM> has a plurality of posts <NUM> extending from the base <NUM> in a generally axial direction relative to the disc that forms the base <NUM>. These posts <NUM> are angularly positioned about the center of the base <NUM>. As illustrated, there are three posts <NUM> on each respective base <NUM>; however, it is contemplated that there could be two, three, or more posts on each base <NUM> and a similar operational effect could be achieved to that which is described herein.

Each of the posts <NUM> have a distal end <NUM> away from the base <NUM>, which includes a tooth <NUM> (collectively, teeth). Each tooth <NUM> has a wedge-like shape and radially projects from the respective post <NUM>. As illustrated, this projection is radially outwardly relative to the central axis. As part of this projecting shape, each tooth <NUM> has a stop surface <NUM> facing back towards the base <NUM> from which the posts <NUM> extend. Each tooth <NUM> also includes tapered surfaces <NUM> on angular ends of the respective tooth <NUM>, which narrow the teeth <NUM> towards the distal ends <NUM> of the posts <NUM>. As illustrated, the tapered surfaces <NUM> include two sections, a bevel that is approximately <NUM> degrees angled relative to the central axis near the distal end <NUM> and an inclined section that runs from the end of the bevel to the axial position of the stop surface <NUM>. While illustrated as flat surfaces, the tapered surfaces <NUM> could also include some amount of curvature and the illustrated shapes are exemplary but not limiting.

While a particular shape and size of the posts <NUM> and teeth <NUM> have been shown, one of ordinary skill in the art will appreciate certain variations may be made while maintaining the functionality described below. For example, the teeth do not need to be triangular wedge shaped, but might be longer arcs. Still further, while the stop surfaces of the teeth are illustrated on the radially outward side of the posts, it is contemplated that differently structure posts and teeth could present these stop surfaces on the radially inward facing side of the posts instead.

As illustrated, each of the half sections <NUM> can further include a center support <NUM> located between the plurality of posts <NUM>. In the form presented, the center support <NUM> is cylindrically shaped and located at the center of each of the half sections <NUM>. This center support <NUM> can be connected to each of the posts <NUM> for a portion of their axial length to improve or control rigidity of the posts <NUM>. The center support <NUM> need not be cylindrical (or even present at all in many designs) and could be in the shape of pillar or rectangular prism. However, when present, the center supports <NUM> may also provide another stop surface (provided by axial face of the center supports <NUM>, which may be flat) when the half sections <NUM> are joined, in addition to the stop surfaces <NUM>, that prevents over-insertion of the two half sections together.

Looking now specifically at <FIG> illustrates the clasp assembly <NUM> of <FIG> in an assembled state in which the pair of half sections <NUM> of the clasp assembly <NUM> are secured to one another. Specifically, to lock or engage the sections <NUM> together, the plurality of posts <NUM> of the pair of half sections <NUM> are axially brought together to engage the teeth <NUM> of the posts <NUM> together. The teeth <NUM> of one of the sections <NUM> are drawn into the space between the teeth <NUM> on the other one of the sections <NUM> and the tapered surfaces <NUM> on angular ends of the posts <NUM> on each of the half sections <NUM> contact one another. This contact between the half sections <NUM> effectuates the elastic deformation of the posts <NUM> to permit the teeth <NUM> of the posts <NUM> to pass by one another until the stop surface <NUM> of one of the half sections <NUM> axially passes the stop surface <NUM> of the other half section <NUM>. The posts <NUM> then deflect back or return to a non-deformed state creating an interlocking engagement between the posts <NUM> on each of the half sections <NUM> at the stop surfaces <NUM> as illustrated in <FIG>.

It can be observed that, for the posts <NUM> of the half sections <NUM> to be in assuredly interlocking engagement, a total angular extent of the stop surfaces <NUM> on each of the pair of half sections <NUM> could be made to exceed <NUM> degrees. By this, it is meant that each of the respective stop surfaces <NUM> can have an angular extent that is measured between the pair of angular ends of that particular stop surface <NUM> (as measured about a central axis) and that, when all of the angular extents of all the stop surfaces <NUM> on one of the half sections <NUM> are added together, this summed total exceeds <NUM> degrees. For example, in the illustrated embodiment, each of the three stop surfaces <NUM> may have approximately <NUM> degrees of angular extent, which collectively sum to approximately <NUM> degrees. While not an absolute requirement, this amount of angular extent necessarily creates some amount of angular overlap in joined identical half sections. Similarly, such a total summed angular extent creates some amount of overlap of the tapered surfaces <NUM> so the tapers almost certainly will result in less than <NUM> degrees of cumulative angular extent on the distal-most end of the posts <NUM>, which will permit these distal ends to interact together during the axial insertion of the sections <NUM> together to create the temporary mechanical displacement of the posts <NUM> and the teeth <NUM>. It will of course be appreciated that, depending on the particularly geometric form and arrangement of teeth, the stop surfaces could have less than <NUM> degrees of extent and the primary consideration is whether the particular geometry employed readily permits one-way engagement of the teeth without the ability to separate the halves once joined.

In the form illustrated, the interlocking engagement of the teeth <NUM> at the stop surfaces <NUM> prevents the half sections <NUM> from separating absent mechanical destruction of at least some of the teeth or post structure. A tensile pull along an axial direction opposite the assembly direction would not pull the two half sections <NUM> apart without destroying the teeth <NUM> because of the non-reversible connection at the stop surfaces <NUM>. Destroying the teeth <NUM> would also destroy the clasp assembly <NUM> and prevent the wristband from staying on the person. Accordingly, the clasp assembly <NUM> provides a non-reversible, secure mechanism for one time-attachment that is tamper proof.

<FIG> illustrate views of another exemplary embodiment, which does not fall into the scope of the present invention, of a clasp assembly <NUM> and a half section <NUM> having a "teeth and cutouts" type design. Again, the clasp assembly <NUM> is designed to be affixed to a wristband, allowing the wristband to be formed into a secured loop around the wrist of the person wearing the wristband using the clasp assembly <NUM>.

The clasp assembly <NUM> includes a pair of half sections <NUM> that, as illustrated in <FIG>, are identical to one another. Each section can again be an integrally formed structure, for example, formed by plastic injection molding. By being formed from plastic, the parts may again be elastically deformable.

Each of the pair of half sections <NUM> includes a base <NUM>, which as illustrated can be generally disc-shaped. However, the base <NUM> can be in various other forms or shapes. For example, the base <NUM> could be rectangular, square, triangular or other polygonal or non-polygonal shape. The shape of the base <NUM> may be altered in some cases or based on the shape of the wristband to which the clasp assembly <NUM> is to be attached.

The base <NUM> has a plurality of posts <NUM> extending from the base <NUM> in a generally axial direction relative to the disc that forms the base <NUM> and about the central axis of the base <NUM>. As illustrated, three posts <NUM> are angularly arranged around the periphery of the base <NUM>. However, it is contemplated that there could be two, three, or more posts on each base <NUM> and a similar operational effect could be achieved to that which is described herein.

Each of the posts <NUM> have a distal end <NUM> away from the base <NUM>, which support and provide a tooth <NUM>. Each tooth <NUM> has a wedge-like shape and radially projects inward towards the central axis from the respective post <NUM>. As part of this projecting shape, each tooth <NUM> has a stop surface <NUM> facing back towards the base <NUM> from which the posts <NUM> extend. This stop surface <NUM> is generally parallel to the axial face of base <NUM> and/or is perpendicular to the central axis. Each tooth <NUM> also includes an inclined surface <NUM> on the axial end of the respective tooth <NUM> that extends downwardly as it extends radially inwards towards that central axis until it meets the stop surface <NUM> to establish the tip of the tooth <NUM>. As illustrated, since both the stop surfaces <NUM> and the inclined surface <NUM> are planar, they come together at an acute angle.

Additionally, the base <NUM> has a plurality of cutouts <NUM> angularly spaced about the peripheral edge of the base <NUM>. Each of the cutouts <NUM> is angularly spaced out from one another about the periphery and has an interposed post <NUM> between cutouts <NUM>, such that as one travels around the periphery of the base <NUM> there is a post-cutout-post-cutout repeating pattern with a center of each feature being <NUM> degrees from the center of the next feature (as there are three of each feature for a total of six features). As illustrated, each of the cutouts <NUM> extends axially from a first axial surface <NUM> of the base <NUM> to a second axial surface <NUM> of the base <NUM> and extends radially inward from an otherwise circular periphery of the base <NUM>. The cutout <NUM> as illustrated is generally arcuate-shaped, with a peripheral edge jutting inwards radially towards the center of the base <NUM>.

In the form illustrated, each of the cutouts <NUM> further have a recess <NUM> that extends further radially inward from the periphery than the cutout <NUM>. The recess <NUM> does not fully extend from the first axial surface <NUM> of the base <NUM> to the second axial surface <NUM> of the base <NUM>, but only fractionally therebetween. Notably, there is at least some stop surface <NUM> created by this recess <NUM> that faces in a generally opposite axial direction from the stop surface <NUM> on the teeth <NUM> and which has a greater length than the tooth <NUM> of another identical half section <NUM> which will ultimately be received in the recess <NUM>.

It should be appreciated that the positioning of the posts <NUM> with teeth <NUM> and the cutouts <NUM> with recesses <NUM> is such that, as will be illustrated in <FIG>, the stop surfaces <NUM> of teeth <NUM> and the stop surfaces <NUM> of the recesses <NUM> will be engageable with one another. As such, there should be some rotational symmetry in the design of the half section <NUM> to permit this engagement and to do so at more than one angular position of the half sections <NUM> with respect to one another.

Looking now specifically at <FIG> illustrates the clasp assembly <NUM> of <FIG> in an assembled state in which the pair of half sections <NUM> of the clasp assembly <NUM> are secured to one another. Specifically, to lock or engage the sections <NUM> together, the plurality of posts <NUM> of the pair of half sections <NUM> and the plurality of cutouts <NUM> with recesses <NUM> are axially brought together to engage the teeth <NUM> of the posts <NUM> with the recesses <NUM> of the cutouts <NUM> (and more specifically to engage the stop surfaces <NUM> of the teeth <NUM> on the posts <NUM> with the stop surfaces <NUM> of recesses <NUM> of the cutouts <NUM> so that cannot be axially withdrawn from one another). To assemble two identical half sections <NUM>, the axial side of the half sections <NUM> having the posts <NUM> are made to face one another and the posts <NUM> of one of the half sections <NUM> are angularly aligned with the cutouts <NUM> on the other of the half sections <NUM>. As the two half sections <NUM> are axially drawn together (as by the action of fastening the clasp on the wristband), the inclined surface <NUM> of the tooth <NUM> comes into contact with an edge <NUM> of the cutout <NUM> between the periphery and the first axial face <NUM>, thereby effectuating the elastic deformation of the post <NUM> radially outward to permit the tooth <NUM> of the post <NUM> to axially pass by the edge <NUM> of the cutout <NUM>. The stop surface <NUM> of the tooth <NUM> then continues to move axially until the stop surface <NUM> passes the corresponding stop surface <NUM> formed by the recess <NUM> in the cutout <NUM>. The posts <NUM> then deflect back or return to a non-deformed state such that each of the teeth <NUM> of one half section <NUM> nests into the corresponding recesses <NUM> of the other half section <NUM>, thereby creating an interlocking engagement between the posts <NUM> on one of the half sections <NUM> with the recesses <NUM> in the cutouts <NUM> on the other half sections <NUM> at the stop surfaces <NUM> and <NUM>. This engagement cannot be readily separated in tension without breaking the teeth <NUM>, posts <NUM>, and/or a wall of the base <NUM> forming part of the recess <NUM>. Accordingly, the clasp assembly <NUM> provides a non-reversible, secure mechanism for one time-attachment.

While a particular geometry has been shown for "teeth and cutouts" type design, variations to the particular illustrated geometry are contemplated.

For example, while a particular shape and size of the posts <NUM> and teeth <NUM> have been shown along with those of the corresponding cutouts <NUM> and recesses <NUM>, one of ordinary skill in the art will appreciate certain variations may be made while maintaining or even improving the functionality described below. For example, there could be slight undercuts on each of the stop surfaces <NUM> and <NUM> that could help to create interlocking engagement. Still further, while the arcuate length of the teeth <NUM> are roughly equal to the arcuate length of the recesses <NUM>, the length of the teeth <NUM> could be appreciably less than the length of the recesses <NUM>, creating a greater range of possible angular arrangements in which connection is possible. As another possibility, a regular polygonal shape may be employed such as a square or hexagon rather than a circle and that regular polygon may have alternating posts and recesses along each side or at each corner.

Still further, there could be different numbers of posts <NUM> and cutouts <NUM> than those illustrated. For example and as illustrated, each base <NUM> has three cutouts <NUM> that correspond to the three posts <NUM> and teeth <NUM>. However, as it is contemplated that there could be two, three, or even more posts <NUM> on each base <NUM> with a corresponding number of cutouts <NUM> and a similar operational effect could be achieved to that which is described herein. As mentioned elsewhere in this disclosure, by maintaining some rotational symmetry in the design, it is possible to have multiple orientations of alignment. Still further, by increasing the number of features, it is possible to reduce the average amount of rotation in order to come into an aligned position in which the two halves may be joined.

Further, as illustrated, the number of the posts <NUM> and teeth <NUM> matches exactly the number of the cutouts <NUM> and recesses <NUM>. However, this need not be the case. For instance, it is contemplated that there could be more recesses <NUM> than posts <NUM> with teeth <NUM>. In such case, there could be various orientations of assembly between the two half sections <NUM> and some recesses may remain unoccupied even when the two half sections <NUM> are joined.

It is further considered that while, in the form presented, the recess <NUM> is generally rectangular-shaped or slightly arcuate-shaped to match the cutout <NUM> where the recess is located in, that other geometries could be used. For example, the recess <NUM> could be square, triangular or other polygonal or non-polygonal shape. In such case, the teeth on the posts may be designed to have similarly shaped mating geometries.

Even beyond this, it is contemplated that the half sections could be modified such that the posts are designed to deflect radially inward (relative it the center axis of the clasp) while the recesses are formed on a centrally-facing surface to effectively reverse the positioning of the mating features and their direction of deflection.

Turning now to <FIG>, these figures illustrate a half section <NUM> of a "cupped surfaces" style for a clasp assembly <NUM> can be assembled from two identical half sections <NUM> as illustrated in <FIG>. This embodiment does not fall into the scope of the present invention.

Again, the clasp assembly <NUM> includes a pair of half sections <NUM> that, as illustrated, are identical to one another. Each half section <NUM> can be an integrally formed unitary structure, for example, formed by plastic injection molding. By being formed from plastic, thin walls of the parts or other sections of them may be elastically deformable.

The base <NUM> has a plurality of posts <NUM> extending from the base <NUM> in a generally axial direction relative to the disc that forms the illustrated base <NUM> and about the center of the base <NUM>. As illustrated, there are four posts <NUM> on each base <NUM> arranged with their stems in a square on the base <NUM>. However, it is contemplated that there could be two or more posts on each base <NUM> and a similar operational effect could be achieved to that which is described herein. Based on the nature of the mating arrangement for this embodiment, it would be contemplated that there would be an even number of posts <NUM> to provide the correct number of mating partners.

As illustrated, the posts <NUM> have alternating male and female features around the square that are shaped to engage with the posts <NUM> of another half section <NUM>. On each half section <NUM>, each of the posts <NUM> have a distal end <NUM> away from the base <NUM> and a proximal end <NUM> near the base <NUM>. As illustrated, two of the posts <NUM> on opposing corners of the square have axially-facing concave surfaces <NUM> extending between their distal ends <NUM> and the proximal ends <NUM>. The posts <NUM> with the axially-facing concave surface <NUM> together form female deformable features. Further, two of the posts <NUM> have outwardly-facing convex surfaces <NUM> extending between the distal end <NUM> and the proximal end <NUM> and are on the two other opposing corners of the square. The posts <NUM> with the outwardly-facing convex surface <NUM> together form male deformable features.

Looking now specifically at <FIG> illustrates a clasp assembly <NUM> constructed from a pair of identical half sections <NUM> as illustrated in <FIG>. Specifically, to temporarily lock or engage the half sections <NUM> together, the female deformable features (that is, the axially-facing concave surfaces <NUM>) and male deformable features (that is, the outwardly-facing convex surface <NUM>) of the pair of half sections <NUM> are axially brought together to simultaneously engage four pairs of outwardly-facing convex surfaces <NUM> with corresponding axially-facing concave surfaces <NUM>. As they are brought together, the outwardly-facing convex surfaces <NUM> contact the axially-facing concave surfaces <NUM> of the posts and effectuate the temporary elastic deformation of the posts <NUM> at least one of inwardly and outwardly to permit the outwardly-facing convex surfaces <NUM> to pass by the distal ends <NUM> of the axially-facing concave surfaces <NUM>. To permit this initial deflection, at the distal end of the female sections there may be a cutout <NUM> that permits entry of the leading distal edge of the slice of the male sections so that a "wedging" action may occur between the mating posts. This action continues until the outwardly-facing convex surfaces <NUM> reach or approach the proximal ends <NUM> of the axially-facing concave surface <NUM>. As they reach the proximal ends <NUM>, the posts <NUM> then return to a non-deformed state that creates an interlocking engagement between the posts <NUM> on one of the half sections <NUM> at the outwardly-facing convex surfaces <NUM> and the axially-facing concave surfaces <NUM> of the posts <NUM> on the other one of the half section <NUM> as illustrated in <FIG>.

The interlocking engagement of the outwardly-facing convex surfaces <NUM> and the axially-facing concave surfaces <NUM> prevents the half sections <NUM> from readily separating absent the application of some threshold tensile force in the direction opposite the direction of insertion described above. Unlike the first two embodiments above, this connection between the two half sections <NUM> to form the clasp assembly <NUM> is reversible and the half sections <NUM> can be non-destructively separated.

The male and female mating features may have various geometric qualities. For one, in some forms and as illustrated, the curvatures or profiles of the axially-facing concave surfaces <NUM> and the outwardly-facing convex surfaces <NUM> may be the same. The axially-facing concave surfaces <NUM> and the outwardly-facing convex surfaces <NUM> may be generally frustospherical surfaces (in roughly quarter sections in the case of four posts). However, to better accommodate insertion, the profile may be slightly elongated to require less deflection of the posts <NUM> during insertion or withdrawal. Likewise, by virtue of both material selection and profile geometries, different threshold forces can be establish for assembly and disassembly.

Similarly, to alter the deflectional properties of the posts <NUM> and their attached mating components, the posts <NUM> and mating features may be made of different wall thickness or made solid. For example, as illustrated, the male sections are illustrated as solid wedges and the female sections are thin-walled such that the thin-walled sections are slightly more prone to deflection. Some of these geometries may also be made with respect to molding considerations and viability.

Typically, the number of female deformable features matches the number of male deformable features. However, it is contemplated that there could be more of one type of feature than the other (for example, more male features than female features or vice-versa) to permit various rotational engagements with one another. Still further, while four posts <NUM> are illustrated on each post, there could be more or fewer on each.

Still further, while the axially-facing concave surface <NUM> is illustrated as having a specific curvature and the outwardly-facing convex surface <NUM> is illustrated as having a specific curvature that closely matches, it should be appreciated that the curvatures of each of the types of posts could have different profiles, so long as the axially-facing concave surfaces <NUM> are capable of forming an interlocking engagement with the outwardly-facing convex surface <NUM>.

Turning now to <FIG> illustrates a half section <NUM> in which a pair of these half sections <NUM> can be assembled into an exemplary "ball and socket depression" type clasp assembly <NUM>. This embodiment does not fall into the scope of the present invention.

The clasp assembly <NUM> includes a pair of half sections <NUM> that, as illustrated, are identical to one another. Each section is an integrally formed structure, for example, formed by plastic injection molding. By being formed from plastic, the parts may be elastically deformable.

Each of the pair of half sections <NUM> includes a base <NUM>, which as illustrated can be generally disc-shaped. However, the base <NUM> can be in various other forms or shapes in the various manners described above.

The base <NUM> has a plurality of posts <NUM> extending from the base <NUM> in a generally axial direction relative to the disc that forms the illustrated base <NUM> and about the center of the base <NUM>. As illustrated, there are two posts <NUM> on each base <NUM>; however, it is contemplated that there could be two or more posts <NUM> on each base <NUM> and a similar operational effect could be achieved to that which is described herein.

Each of the posts <NUM> have a generally ball-shaped surface <NUM> or head positioned away from the base <NUM>. The generally ball-shaped surface <NUM> or head may have a radius and/or a curvature. As illustrated, the generally ball-shaped surface <NUM> is generally spherical; however, other shapes may be employed.

The base <NUM> also has a plurality of socket depressions <NUM> spaced about the center of the base <NUM>. Each of the socket depressions <NUM> may have a radius and/or curvature that may be the same or slightly different from the radius and/or curvature of the generally ball-shaped surfaces <NUM>. The socket depressions <NUM> as illustrated can be generally circular or spherical-shaped. However, the socket depressions <NUM> can be in various other forms or shapes and are contemplated as generally corresponding to the profile of the ball-shaped surfaces <NUM> of the posts <NUM>. It is also contemplated that the shape of the socket need not exactly match the head of the post, but that they should correspond in form so as to permit the snap-type engagement with one another described below.

One or both of the ball-shaped surface <NUM> and the socket depressions <NUM> are able to deform slightly due to the elasticity of the plastic material to create individual interlocking engagement between one of the heads and a corresponding one of the sockets. Accordingly, the depressions <NUM> should be more than half of the volume of the hypothetical ball being inserted into it so that some amount of "capture" or interlocking occurs between the head or ball and socket.

Looking now at <FIG> illustrates the clasp assembly <NUM> of <FIG> in an assembled state in which the pair of half sections <NUM> of the clasp assembly <NUM> are secured to one another. Specifically, to lock or engage the sections <NUM> together, the plurality of posts <NUM> with ball-shaped surfaces <NUM> and the socket depressions <NUM> of the pair of half sections <NUM> are axially brought together to engage the ball-shaped surfaces <NUM> or heads of the posts <NUM> with the socket depressions <NUM> on the base <NUM>. During insertion, the ball-shaped surfaces <NUM> on one of the half sections <NUM> contact the socket depressions <NUM> on the base <NUM> of the other half section <NUM>. This contact between the half sections <NUM> effectuates the elastic deformation of ball-shaped surfaces <NUM> and/or socket depressions <NUM> to temporarily and elastically crush ball-shaped surfaces <NUM> and/or expand the socket depression <NUM> to permit entry of the head into the socket. Upon sufficient insertion, the ball-shaped surfaces <NUM> "snap" into the socket depressions <NUM> and both return towards their original profiles. In the case of the illustrated embodiment, four such interlocking snap connections are made of this nature in near simultaneous fashion.

The interlocking engagement between the ball-shaped surfaces <NUM> and the socket depressions <NUM> prevents the half sections <NUM> from separating absent the application of a tensile force above a threshold force in the axial direction counter to the direction of insertion. Like the third embodiment, but unlike the first two embodiments, the heads can be removed from the sockets non-destructively and so the connection of the clasp assembly <NUM> is reversible.

As illustrated, there are two socket depressions <NUM> and two ball-shaped surfaces <NUM> on each base <NUM>. However, it is contemplated that there could be two or more socket depressions <NUM> and two or more ball-shaped surfaces <NUM> on each base <NUM> and a similar operational effect could be achieved to that which is described herein. While illustrated as an alternating arrangement between the socket depressions <NUM> and the posts <NUM> with ball-shaped surfaces <NUM>, the posts <NUM> with ball-shaped surfaces <NUM> and the socket depressions <NUM> may be arranged in other fashions. For example and in a non-limiting exemplary arrangement shown in <FIG> depicting an alternative half section <NUM>, the posts <NUM> with ball-shaped surfaces <NUM> and the socket depressions <NUM> may be arranged at the corners of a square. In this form illustrated in <FIG>, the posts <NUM> with ball-shaped surfaces <NUM> are at the corners on one-half of the square and the socket depressions <NUM> are at the corners on the other half of the square.

Generally speaking, discrete rotational symmetry is used in all of these embodiments to construct designs for each half section so that identical half sections can be used with one another. The half section is designed to couple with itself using symmetry constructs. The discrete rotational symmetry (<NUM>°/n), maximum rotation to close, and average rotation to close of <NUM> to <NUM> coupling mechanisms are shown in the table below:.

Rotational symmetry for an object of order n occurs when rotating the object by <NUM>°/n does not change the object. Taking common joints and fractionalizing them or copying individual joints many times allows for the creation of clasps that both symmetrical and interlocking. In this way, the classic male/female designs for coupling can be obfuscated. The higher degrees of symmetry also benefit the closing of the clasps by requiring less rotation (maximum or average) to align the half sections for closure. Those skilled in the art of plastic injection molding and additive manufacturing techniques will understand that this complexity for small couplings can be extremely hard to engineer and that there are diminishing gains as n approaches <NUM> and beyond. Preferably, the discrete rotational symmetry of the half sections for the assembly disclosed are between <NUM> and <NUM>, more preferably between <NUM> and <NUM> for the greatest combination of mechanical strength, manufacturing simplicity and usability.

Claim 1:
A clasp assembly (<NUM>) comprising:
a pair of identical half sections (<NUM>) configured to be coupled together, in which each half section (<NUM>) comprises one or more deformable features that are designed to deform during closure to create an interlocking engagement between each half section (<NUM>) characterized in that the one or more deformable features are posts (<NUM>) extending axially from a base (<NUM>) of the respective half section (<NUM>), each of the posts (<NUM>) having a tooth (<NUM>) with a wedge-like shape, the respective tooth (<NUM>) provided at the distal end (<NUM>) away from the base (<NUM>) and radially projects from each of the posts (<NUM>), with the tooth (<NUM>) having a stop surface (<NUM>) facing the base (<NUM>); wherein each of the pair of identical half sections (<NUM>) has discrete rotational symmetry; wherein, after interlocking engagement, the pair of identical half sections (<NUM>) are not completely axially separable without permanent mechanical destruction of the one or more deformable features, wherein the interlocking engagement is created between the teeth (<NUM>) at the stop surfaces (<NUM>), wherein the teeth (<NUM>) further include tapered surfaces (<NUM>) on angular ends thereof that narrow as the teeth (<NUM>) extend towards the distal end (<NUM>) of the respective post (<NUM>).