BACKGROUND OF THE INVENTIONThe present invention relates in general to safety straps and, in particular, to watch bands or other straps with a tear away safety feature.
Watches and other wearable technology are worn, for example, around a wearer's wrist, using a strap or band. Such bands typically wrap around the circumference of a person's wrist or other body part and fasten via a buckle or clasp. Such straps can also be made from many materials including, without limitation, silicone or other rubbers, leather, nylon, canvas, etc.
Wearable technology and wrist watches continue to have increased application in industrial environments, sports environments, and healthcare environments. In such settings, wearer safety is a major concern. For example, businesses and workers in an industrial setting want to be assured that if any feature of their watch or watch band (as well as other wearable bands or straps, such as belts, suspenders and other straps) is stuck in a machine or conveyor, the watch should break loose from the wrist or other body part, reducing the likelihood that the wearer would be subject to physical harm or injury.
BRIEF SUMMARYThe present disclosure appreciates that it would be desirable to provide a watch band or other wearable strap that will tear away from the wearer under specific conditions.
A watch band or other wearable strap that may be made from a great variety of base materials including, but not limited to, silicone rubber. The wearable strap will have an ultimate tensile strength that is specific to the intrinsic properties of the base material and the dimensions of the material. The ultimate tensile strength specifies the force required to break the wearable strap and is typically expressed as an amount of force per unit area (e.g., pounds per square inch (psi) or Pascals (Pa)). As one example, the ultimate tensile strength of silicone similar to that used in watch bands made by Barton® Watch Bands is approximately 1233 psi or 8.5 MPa.
If the tensile strength of the base material used in a wearable strap is known, then the force at which the wearable strap will “break away” or “tear away” can be controlled by selecting the cross-sectional area and/or material properties of the wearable strap at one or more regions. Accordingly, in at least some embodiments, a watch band or other wearable strap includes at least one tear away region at which the cross-sectional area of the base material is reduced, such that the force required to break away or tear away the wearable band from the body of the wearer is predetermined. In other embodiments, the material utilized to form the tear away region(s) of the wearable strap may alternatively or additionally have a lower ultimate tensile strength than the material utilized to form other portions of the wearable strap, again permitting the force required to break away or tear away the wearable band from the body of the wearer to be predetermined. The tear away region(s) may take on many embodiments and may come in many shapes and locations, some of which are disclosed herein without limitation.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGSFIG. 1 illustrates a wearable strap including at least one tear away region;
FIG. 2 depicts a detailed elevation view of a wearable strap having a tear away region in which the lower ultimate tensile strength of the tear away region is achieved by forming the tear away region with decreased thickness on an inner side of the wearable strap;
FIG. 3 illustrates another detailed elevation view of a wearable strap having a tear away region in which the lower ultimate tensile strength of the tear away region is achieved by forming the tear away region with decreased thickness on an outer side of the wearable strap;
FIG. 4 depicts another detailed elevation view of a wearable strap having a tear away region in which the lower ultimate tensile strength of the tear away region is achieved by forming the tear away region with a different material having a lower ultimate tensile strength; and
FIG. 5 illustrates a detailed plan view of a wearable strap having tear away regions formed at a plurality of adjustment holes.
DETAILED DESCRIPTIONWith reference now to the figures and in particular with reference toFIG. 1, there is illustrated a wearable strap, which in this example is awatch band100. Wearable straps likewatch band100 are configured to be worn around an appendage, waist, neck, head, or other body part of a human or an animal body and are typically (but not necessarily) fastened with a buckle, clasp, tie, or other closure mechanism. In general, the wearable strap is elongate and thus has a length (or circumference) that greatly exceeds its width and thickness. The wearable strap may be made from any number of base materials including, without limitation, silicone rubber, leather, nylon, canvas, metal, etc. In some cases, the base material may also be combined with one or more finish materials, for example, to achieve a desired aesthetic appearance. As noted above, each base material has an intrinsic ultimate tensile strength.
In the illustrated embodiment, watchband100 is a two-part wearable strap, including afirst part104aand asecond part104b. Each offirst part104aandsecond part104bhas a respective length extending between afirst end106aor106bandsecond end108aor108b. In addition, each offirst part104aandsecond part104bhas a width W, which is orthogonal to the length (and can vary along the length) and extends betweenedges105. Each offirst part104aandsecond part104balso has a thickness T (seen best inFIGS. 2-4, which are described below). For example, it is typical for a watch band such aswatch band100 to have an overall length of between 165 mm and 330 mm, a width of between 5 mm and 40 mm, more commonly, between 16 mm and 30 mm, and a thickness of between 0.5 mm and 5 mm and, more commonly, between 1 mm and 4 mm.
Referring specifically tofirst part104aofwatch band100,first end106aincludes or is coupled to a watch case attachment, which in this embodiment is anintegral spring bar109athat engages a first pair of lugs of a watch case.Second end108aoffirst part104ais coupled to a conventionalwatch band buckle112. Buckle112 includes aloop114 and atang116 that is rotatable about a hidden bar ofloop114.
Second part104bofwatch band100 also includes a watch case attachment at itsfirst end106b, which in this embodiment is again anintegral spring bar109bthat engages a second pair of lugs of the watch case. Betweenfirst end106bandsecond end108bofsecond part104b, a series ofholes118 are formed throughsecond part104bto permitfirst part104ato be coupled tosecond part104bby the insertion of second end110bthroughloop114 and the insertion oftang116 through a selected one ofholes118. By varying which one of theholes118tang116 is inserted through, the overall wearable length of innercircumference watch band100 can be adjustably sized in accordance with the wearer's wrist size and/or preference (typically, between 125 mm and 250 mm). The portion ofsecond part104btoward second end110bthat extendspast buckle114 can be retained in close relation tofirst part104aby one ormore band retainers119 freely riding onfirst part104a.
In one or more embodiments, a wearable strap such aswatch band100 includes one or more break away or tear away regions of lower ultimate tensile strength than other portions of the wearable strap. For example, in the illustrated example, watchband100 includes at least one tear awayregion120 that has a lower ultimate tensile strength than other portions ofwatch band100. The ultimate tensile strength of tear awayregion120 is controlled so thatwatch band100 will reliably break away or tear away from the body when subjected to at least a minimum breaking force in excess of the ultimate tensile strength of tear awayregion120, even though that minimum breaking force is less than the ultimate tensile strength of other regions or components ofwatch band100. The minimum breaking force can be predetermined by controlling the properties of the tear awayregion120 ofwearable strap100.
For example, in some embodiments, the ultimate tensile strength of the tear awayregion120 and the minimum breaking force at which thewatch band100 will break are controlled by the cross-sectional area of thewatch band100 in tear awayregion120. For example, the cross-sectional area ofwatch band100 in tear awayregion120 can be reduced as compared to other areas ofwatch band100. This reduced cross-sectional area can be realized in many different embodiments and in many shapes and locations, only some of which are disclosed herein without limitation.
As shown in greater detail in the elevation view ofwatch band100 given inFIG. 2, in one embodiment, the ultimate tensile strength of tear awayregion120 is reduced as compared to other regions ofwatch band100 by reducing the thickness T ofwatch band100 at one location. This reduction in thickness T reduces the cross-sectional area at tear awayregion120 and consequently reduces the minimum breaking force required to tear away watchband100 away from the body. It should be noted that the reduction in thickness T is independent of the width W, meaning that tear awayregion120 can have a width W consistent with that of the surrounding and/or adjoining portions ofwatch band100. InFIG. 2, the reduction in thickness T is made on aninner side200aofwatch band100 rather than on anouter side200b, thus preserving the consistency of the aesthetic appearance of tear awayregion120 with the remainder ofwatch band100 whenwatch band100 is in use. Alternatively, as shown in the elevation view given inFIG. 3, the reduction in thickness T can be made onouter side200bofwatch band100 in addition to (or rather than) oninner side200a. This alternative design enables tear awayregion120 to be readily visually verified whenwatch band100 is in use.
AlthoughFIGS. 2-3 show specific embodiments in which watch band110 has approximately half of the thickness Tin tear awayregion120 as compared to the adjoining portions ofwatch band100, it should be understood that the relative reduction in thickness will depend on the geometry ofmatch band100, the material properties of the base material ofwatch band100, and the desired minimum breaking force. For example, assuming a silicone watch band having band having an ultimate tensile strength of 8.5 MPa, the cross-sectional area of the watch band intear way region120 would be approximately 3.5 mm2for an approximately 3 kg minimum breaking force and approximately 25.0 mm2for an approximately 20 kg breaking force. If this silicone watch band has a uniform width of 18 mm including within tear awayregion120, the thickness of the watch band intear array region120 would then be about 0.2 mm for a 3 kg minimum breaking force and about 1.25 mm thick for a 20 kg minimum breaking force.
The desired cross-sectional area of the tear awayregion120 can also be obtained in many ways. For example, as an alternative to (or in addition to) employing a reduced thickness T (as shown inFIG. 2),watch band100 can have a narrower width W at tear awayregion120 than at the surrounding portions ofwatch band100. Thus, for example, to obtain a desired cross-sectional area, material could be removed or eliminated from one or both edges ofwatch strap100, and/orinner side200a, and/orouter side200b.
In some embodiments, the ultimate tensile strength of the tear awayregion120 and the minimum breaking force at which thewatch band100 will break are controlled by the use of a different material in tear awayregion120 than other portions ofwatch band100. For example,FIG. 4 is an elevation view of awatch band100 formed of afirst material400 that includes a tear awayregion120 including asecond material402 having a lower ultimate tensile strength than thefirst material400. For example, iffirst material400 is a metal such as stainless steel,second material402 can be a silicone having a lower ultimate tensile strength than the metal. As another example,first material400 may be a silicone having a higher ultimate tensile strength, andsecond material400 may be a silicone characterized by a lower ultimate tensile strength. In the embodiment shown inFIG. 4,second material400 is utilized only across a portion of the overall cross-sectional area ofwatch band100 in tear awayregion120; in other embodiments,second material400 may form the entire cross-section ofwatch band100 in tear awayregion120. Further, in some embodiments,second material400 may have a distinctive visual appearance (e.g., a different color and/or texture) so thatwatch band100 can be readily visually verified as a tear away strap. It should be noted that if a differentsecond material402 having a lower ultimate tensile strength is utilized to form tear awayregion120, tear away region can have the same cross-sectional area as adjoining portions ofwatch band100, a consistent cross-sectional area with adjoining portions of watch band100 (i.e., the same cross-sectional area as the adjoining portions or a cross-sectional area that varies from the adjoining portions in accordance with the overall contour of watch band100), or even a larger cross-sectional area than the adjoining portions ofwatch band100.
It should be understood that any number of tear away regions can be implemented along the length of a wearable strap, such aswatch band100. Further, a tear away region can be implemented at any location along the length of a wearable strap as long as the tear away region would be subjected to force if the wearable strap gets trapped, snagged, or caught in or on an object. For example, with respect to watchband100, a tear awayregion120 can be proximate to (e.g., within 15 mm of) the watch case attachment (e.g., spring bars108aor108b) onfirst end108aor108b. As another example, a tear awayregion120 can be implemented across the width W ofwatch band100 at the location of each ofholes118, as shown inFIG. 5 By ensuring that a potentially breaking force is applied to at least one tear away region, if any part of the wearable strap becomes trapped, snagged, or caught, the potentially breaking force is applied to the tear awayregion120 through the wearable strap and will cause the wearable strap to break at the tear awayregion120 if the potentially breaking force is equal to or greater than the minimum breaking force. The minimum breaking force can vary based on, among other things, the environment of intended use, the intended use of the wearable strap, and/or the body member about which the wearable strap is intended to be worn. For example, in some embodiments, the minimum breaking force is between 5 lbs. and 50 lbs., and more particularly, between 10 lbs. and 30 lbs. In at least some embodiments, the ultimate tensile strength of the tear away region and thus the minimum breaking force is specifically designed to be less than that of the watch case attachments andbuckle114.
Although various embodiments of a watch band including a tear away region have been described, it should be understood that the principles described herein can also be applied to any wearable strap, including, without limitation, rings, bracelets, necklaces, belts, lanyards, suspenders, garment fasteners, pet collars, headlamp bands, and wearable straps for wearable technology (e.g., mobile phones, heart rate monitors, fitness trackers, etc.). Further, although a wearable strap having a tear away region as described provides assured safety in industrial environments, it should be understood that the wearable strap can provide enhanced safety in other environments, including sports environments and healthcare environments.
While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best modes thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiments, methods, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention as claimed.