Patent Publication Number: US-2022235847-A1

Title: Interchangeable attachment device

Description:
BACKGROUND 
     Attachment components and systems are used extensively in different devices and secure different components in desired configurations. An attachment system may attach or secure a first component, such as a cable, to a second component, such as a strap. In this and other scenarios, an attachment system is desired to provide robust and reliable support and attachment between the components. 
     Existing attachment systems may be complex, bulky, costly to manufacture, and/or difficult to use. These issues are especially evident in the fields of orthopedic, prosthetic, and medical devices, where proper functioning of different components across many unique and individual dimensions and needs is essential. The cost and complexity of manufacturing is compounded by the need to properly provide and/or match corresponding attachment interfaces between different components. Attachment systems must also be intuitive to use to ensure proper/compliant use, particularly in orthopedic, prosthetic, and medical device contexts. 
     It may be desired to connect a cable to a strap, such as in a tensionable dynamic force strap in an orthopedic brace, in which a cable attaches to a tensioning device such as a dial-tensioner to apply tension in the dynamic force strap to provide the desired level of forces or immobilization on a portion of the user&#39;s anatomy. The cable may attach or route to a cable attachment interface on or cooperating with a strap, such as a device having a channel arranged to receive the cable, but the cable interface may not be compatible with certain strap interfaces and accordingly may be difficult to properly attach to a strap. Such a scenario increases the complexity of manufacturing as specific strap interfaces must be provided to properly correspond to the cable interface to attach the cable to the strap. 
     The difficulty of properly matching different attachment interfaces is further compounded by the challenge of including desired features in the attachment interfaces. Dial-tensioning devices, elastic components, and other features may be needed at the attachment between components, which further adds to the cost and complexity of reliably and robustly attaching two components. 
     There is a need for an improved attachment system that overcomes the problem of existing attachment systems, being poorly adapted to match and attach between different components and thus requiring that component-specific attachment components are provided, which increases the costs of attaching two components, and reduces the likelihood of compliant use. There is also a need for an attachment device that overcomes the problem of attachment devices peeling away or otherwise being prone to accidental detachment from a strap or component to which they are attached. 
     SUMMARY 
     Embodiments of the interchangeable attachment device of the disclosure advantageously overcome the challenges of existing attachment systems that are difficult to properly match and attach by providing interchangeable component interfaces that are more simple, intuitive, and cost-effective to match, and provide reliable and robust attachment. The interchangeable attachment device of embodiments of the disclosure may generally include a first attachment interface supporting and/or attached to a first component and a second corresponding attachment interface supporting and/or attached to at least a second component. The advantage of the first and second attachment interfaces is that different components may be swapped or interchanged according to the desired first and second components, allowing a user or clinician to readily adapt the attachment system according to its particularities and/or a user&#39;s needs. 
     The first and second attachment interfaces may each comprise corresponding locking or attachment portions that robustly and reliably secure the interfaces to each other in an intuitive, predictable, and cost-effective way. The attachment interfaces may be arranged to attach at an attachment junction and may define features such that the attached first and second attachment interfaces define a smooth and/or substantially unitary structure in the attached state. 
     The attachment portions may comprise corresponding protruding and receiving portions defined by the corresponding attachment interfaces. A protruding portion according to embodiments may comprise an extending portion and an engagement part arranged to cooperate with a retention member on the receiving portion. A receiving portion according to embodiments may be arranged to receive the corresponding protruding portion to ensure a robust attachment and may facilitate a removable attachment by providing locking/unlocking elements. 
     A locking/unlocking element according to embodiments may be provided on the protruding portion and arranged to cooperate with a corresponding recess defined by the receiving portion, allowing a user or manufacturer to disengage the attached first and second attachment interfaces. A body portion of the attachment interface defining the receiving portion may define an aperture or other feature arranged to facilitate disengagement of the locking portion from the recess by a user. 
     The first attachment interface may support and cooperate with a cable, such as a cable in a dial-tensioning device. The second attachment interface may support or attach to straps, such as dynamic tensioning straps, frame components, additional cables, and/or any suitable component. The first attachment interface is not limited to cooperating with a cable, but rather may be configured with any component or feature for securing the second attachment interface to an object. It may comprise clips, clamps, teeth, D-rings, overmolded portions, adhesives, snaps or other fasteners, and/or other features known to the skilled person. 
     The second attachment interface may comprise an attachment or locking structure arranged to secure the second component, either releasably or non-releasably. In embodiments in which the second component is a strap, the attachment structure may comprise a locking structure for securing the straps to the second attachment interface, including but not limited to clips, clamps, teeth, D-rings, overmolded portions, adhesives, and/or other features. 
     The first and/or second attachment interface may support additional features arranged to cooperate with the first and/or second components, such as dial-tensioning devices. The first and/or second attachment interface may define features such as elastic segments that allow for flexibility and/or stretching between the first and second attachment interfaces. Embodiments of an attachment system comprising more than two attachment interfaces and/or components arranged for being interchangeably attached are also contemplated. 
     These and other features, aspects, and advantages of the present disclosure will become better understood regarding the following description, appended claims, and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawing figures are not necessarily drawn to scale, but instead are drawn to provide a better understanding of the components thereof, and are not intended to be limiting in scope, but to provide exemplary illustrations. The figures illustrate exemplary configurations of an attachment system, and in no way limit the structures or configurations according to the present disclosure. 
         FIG. 1  shows an elevational view of an interchangeable attachment device according to an embodiment. 
         FIG. 2  shows a side perspective view of a cable attachment portion according to the attachment system of  FIG. 1 . 
         FIG. 3  shows a side view of the cable attachment portion of  FIG. 2 . 
         FIG. 4  shows a side perspective view of a strap attachment portion according to the interchangeable attachment device of  FIG. 1 . 
         FIG. 5  shows a partial cutaway view of a strap attachment interface according to the strap attachment portion of  FIG. 4 . 
         FIG. 6  is a front plan view of another embodiment of a strap attachment. 
         FIG. 7  is a rear plan of the strap attachment of  FIG. 6 . 
         FIG. 8  is a cross-sectional view taken along line IIC-IIC in  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS 
     A better understanding of different embodiments of the disclosure may be had from the following description read with the accompanying drawings in which like reference characters refer to like elements. While the disclosure is susceptible to various modifications and alternative constructions, certain illustrative embodiments are in the drawings and are described below. It should be understood, however, there is no intention to limit the disclosure to the embodiments disclosed, but on the contrary, the intention covers all modifications, alternative constructions, combinations, and equivalents falling within the spirit and scope of the disclosure. 
     The interchangeable attachment device embodiments of the present disclosure advantageously address the problem of existing attachment interfaces only being suitable for certain components, which increases the cost and complexity of providing or manufacturing devices and reduces compliant use. The problem is addressed by providing attachment interfaces of an interchangeable attachment device which are configured to attach to different components and provide a robust and reliable attachment therebetween. 
       FIG. 1  shows an elevational view of an interchangeable attachment device  100  according to an embodiment of the disclosure. The attachment device  100  may comprise a first attachment interface  102  and a second attachment interface  104  selectively securable to one another. By “selectively securable,” the first attachment interface  102  can be removed at will from the second attachment interface  104 . The first attachment interface  102  may be arranged as a cable interface supporting a cable such as a tensioning cable, as taught in U.S. Pat. No. 8,277,401, granted on Oct. 2, 2012, and incorporated herein by reference. The second attachment interface  104  may be arranged as a strapping interface supporting or connecting to a strap such as a dynamic force strap, although it will be understood that the first and second interfaces  102 ,  104 , and the cables and straps connected thereto, are merely exemplary, and more and other suitable components may be provided in other embodiments of the disclosure. 
     An example of the strap interface may be found in at least U.S. Patent application publication no. 2019/0105188, published on Apr. 11, 2019, which belongs to the applicant of the present disclosure and is incorporated herein by reference. In other embodiments, the interchangeable attachment device  100  may attach a cable to a strap using a mounting bracket that defines a cable channel for slidably receiving the cable through a thickness of the bracket, and allowing the strap to be tensioned by the cable, as described in U.S. Patent application publication no. 2017/0348131, published on Dec. 7, 2017, which belongs to the applicant of the present disclosure and is incorporated herein by reference. The depiction of a connection between a cable as a first component and a strap as a second component is merely exemplary, and any type or number of components may be joined using embodiments of the interchangeable attachment device  100  according to the disclosure. 
     The interchangeable attachment device  100  advantageously may facilitate a robust and reliable attachment between the first and second interfaces  102 ,  104 , and by consequence between the components supported by the first and second interfaces  102 ,  104 . In the depicted embodiment, the first and second interfaces  102 ,  104  are joined at an attachment junction  112 , which may be arranged to facilitate a robust and snug engagement between the first and second interfaces  102 ,  104  such that the interchangeable attachment device  100  defines a substantially unitary body or structure. As shown in  FIG. 1 , the first and second interfaces  102 ,  104  are generally coextensive relative to one another at the attachment junction  112 . 
     The first and second interfaces  102 ,  104  may be arranged to be interchangeable, such that attachment interfaces may be easily and cost-effectively swapped, substituted, or replaced as necessary. In the context of an orthopedic brace, a strap may need to attach to a cable of a dial-tensioning element. However, existing dial-tensioner-compatible attachments may require that the strap attachment is specially configured to accommodate the existing dial-tensioner and/or cable attachments. 
     By providing an interchangeable attachment device  100  comprising first and second interchangeable attachment interfaces  102 ,  104  according to embodiments of the disclosure, the cable may be simply and reliably attached to the strap without providing numerous and/or specialized quantities of attachment components each of which is necessarily specific to a different component. Manufacturing costs and complexities are reduced, as the number and complexity of attachment systems that must be provided and/or stocked as part of the manufacturing process are substantially reduced. Compliant use is also increased, as the intuitiveness of use of a reduced number of attachment interface types is increased relative to existing attachment devices. 
     As seen in  FIGS. 2-3 , in embodiments in which the first interface  102  is arranged as a cable interface to attach a cable  103 , the cable interface  102  may comprise a body  150  defining through a thickness of the body  150  a channel  138  accessible through apertures  139 . The channel  138  may allow for sliding translation of the cable  103  therethrough, which may allow for greater flexibility and ease of use. A first component supported by the cable interface  102  may be a cable  103 , such as a cable utilized by a dial-tensioning device, and may be arranged to pass through and secure to the first attachment interface  102  at or through the channel  138 . The body  150  may further define a plurality of apertures  110 ,  140  extending a distance into or through the body  150 . The plurality of apertures  110 ,  140  may correspond to and/or expose a portion of the channel  138  such that a corresponding portion of the cable is visible through the apertures  110 ,  140 . 
     The cable  103  may be provided with indicia that a user may view through the plurality of apertures  110 ,  140  for ascertaining the desired level of tension or fit. The plurality of apertures  110 ,  140  may also advantageously reduce bulk, weight, and therefore cost of the first attachment interface  102 . The first attachment interface  102  may have distinct first and second sides  155 ,  156 , with a different plurality and pattern of apertures corresponding to each side. For instance, the first plurality of apertures  110  located on the first side  155  may have a different pattern than a second plurality of apertures  140  located on the second side  156  opposite the first plurality of apertures  140 . In embodiments, the first attachment interface  102  may be arranged to lock the cable in place and not to allow sliding translation or adjustment of the cable through the channel  138 . 
     The cable  103  may be formed of any suitable material, including metal, alloys of metals, polymer, fiber-filled polymers, combinations thereof, or any other suitable material. The cable  103  may be formed of materials allowing the cable  103  to flexibly extend from and within the first attachment interface  102 . In embodiments, the cable  103  is formed from a different material than the material forming the first attachment interface  102 . 
     The first attachment interface  102  may be provided with a locking element, provided in the depicted embodiment as a protruding portion  124 , arranged to correspond and attach to a corresponding locking element, formed in the depicted embodiment as a receiving portion  122 , on the second attachment interface  104 . The protruding portion  124  may be elongate and extending generally along a width of the first attachment interface  102 . The protruding portion  124  may comprise an extension part  126  extending from the body  150  towards the second attachment interface  104  and supporting an engagement part  125 . The engagement part  125  may form a lip or an edge that extends along substantially an entirety of the protruding portion  124  and may be arranged to slidably engage a corresponding lip or edge on the corresponding receiving portion  122 . In embodiments, the engagement part  125  may be bifurcated by and extend along opposed sides of the extension part  126 . The depiction of complementary protruding and receiving portions  124 ,  122  is merely exemplary, and any suitable connection mechanism may be used and is contemplated by the disclosure. 
     The protruding portion  124  and the engagement part  125  may be bounded by a stop-engaging surface  127  on a first end of the protruding portion  124  and by an engagement stop  134  at a second, opposed end of the protruding portion  124 . The stop-engaging surface  127  and the engagement stop  134  may be arranged to cooperate with a corresponding receiving portion  122 , as described in greater detail below. 
     Alternative arrangements of the protruding portion  124  are envisioned. The arrangement of the engagement part  125  relative to the extension part  126  need not be symmetric and need not be centered relative to the body  150  of the first attachment interface  102 . Any suitable locking portion arranged to attach to a corresponding locking portion may be used and is contemplated by the disclosure. 
     As discussed, the first attachment interface  102  may define distinct first and second sides  155 ,  156  between the first and opposed ends. The first side  155  may have a substantially flat surface, while the second side  156  may define a curved surface defining a profile  157 . One of the first and second sides  155 ,  156  may be arranged as a cosmetic or upward-facing side, while the opposite side may be arranged to lay flat against an article or component underneath the opposite side. In certain embodiments, the first side  155  may be arranged to lay flat against components underneath it, such as against the frame or body of an orthopedic or prosthetic device. This arrangement advantageously reduces bulk and complications of use. The second side  156  may define an aesthetically pleasing and easy-to-grip surface, including frictional or grip-enhancing features or indicia, to face upwards and to be engaged by a user. 
     The first attachment interface  102  may be formed of any suitable material, including metal, polymer material including thermoset and thermoplastic materials, generally as plastic materials, fiber-filled polymers such as carbon fiber, combinations thereof or otherwise. The first and second attachment interfaces  102 ,  104  may be formed from rigid or semi-rigid materials, and more specifically from materials different from the first and second components. 
     In embodiments, the protruding portion and engagement portion  124 ,  125 , and regions defining the channel  138  may be formed of structurally sound material for ensuring a robust and reliable attachment, while other regions may be formed of lightweight and/or resilient material. The entire attachment interface  102  may be formed of a lightweight and/or resilient material. It will be understood that the described embodiments are merely exemplary, and other arrangements, shapes, and structures are contemplated within the disclosure. 
     As seen in  FIGS. 4 and 5 , a second attachment interface  104  may be arranged to correspond to and attach to the first attachment interface  102  with a reliable and robust attachment and in a simple, intuitive manner. The second attachment interface  102  may also be arranged to support or connect to a second component. The first and second components may thereby be connected to each other. In certain embodiments, the second component may be formed as one or more straps  106 ,  108 . In embodiments in which the first component is a cable and the second component is the one or more straps  106 ,  108 , a more reliable, robust, simple, and intuitive attachment between a cable, such as a tensioning cable, and straps, such as dynamic force straps, may be provided compared to existing component-specific attachment devices, as the interchangeability of attachment interfaces according to embodiments of the disclosure simplifies the provision of matching attachment portions. 
     The second attachment interface  104  may be arranged to attach to the first attachment interface  102  at the attachment junction  112  by defining a receiving portion  122  corresponding to the protruding portion  124  that is defined by the first attachment interface  102 . In an embodiment, the receiving portion  122  may be defined in a body  114  of the second attachment interface  104  such that when the first and second attachment interfaces  102 ,  104  are attached, the interchangeable attachment device  100  defines a smooth and substantially unitary structure. The second attachment interface  104  may comprise first and second sides  116 ,  118  corresponding to the first and second sides  155 ,  156  of the first attachment interface  102 . 
     In embodiments, the first attachment interface  102  may define portions or shoulders  136  at appropriate portions of the body  150 , for example at an end portion of the body  150 . The shoulders  136  may be arranged to abut a corresponding portion of an end portion or the top-most surface of the body  114  of the second attachment interface  104  in the attached configuration such that the interchangeable attachment device  100  comprises a smooth, continuous, and substantially unitary structure with no or substantially no gaps defined between the abutting surfaces of the end portions of the first and second attachment interfaces  102 ,  104 . 
     The receiving portion  122  may comprise a receiving channel  123  extending through at least part of a thickness of the body  114  and defining an aperture  126  on a first side of the second attachment interface  104 . The receiving channel  123  may be defined in part by a vertical channel  154  arranged to overlap, at least partially, an inserted protruding portion  124  of the first attachment interface  124 . The vertical channel  154  may extend from a single side of the receiving channel  123  or may extend from both sides of the receiving channel  123  and may define a region (not shown) through which the extension part  126  may pass as the protruding portion  124  slidably engages the receiving portion  122 . 
     The receiving channel  123  may be bounded at a second end opposite the aperture  126  by a terminal  152 . The terminal  152  may be formed as a stop or a wall and may be arranged to engage the stop-engaging surface  127  defined by the protruding portion  124 . The cooperation of or contact between the terminal  152  and the stop-engaging surface  127  indicates a complete insertion of the protruding portion  124  into the receiving portion  122  in an insertion direction Dins. At an opposed first end of the receiving channel  123 , and proximate the aperture  126 , a detent  142  may be formed for receiving the locking element  132 . The detent  142  may be formed as a recess arranged to interengage the locking/unlocking element  132 . In other embodiments, a locking/unlocking mechanism may be defined proximate the terminal  152 , exterior to the channel  123 , or within an interior portion of the channel  123 . 
     In embodiments, the locking/unlocking element  132 , which may extend downwardly from the protruding portion  124 , may extend into and interengage the detent  142  to lock the first and second attachment interfaces  102 ,  104  in place relative to one another by preventing the protruding portion  124  from sliding out of the receiving portion  122  in a direction opposite the insertion direction DIns. 
     An aperture  130  may be defined in the body  114  and extends through at least a partial thickness of the body  114  to the detent  142 . A user, manufacturer, or clinician may disengage the first and second attachment interfaces  102 ,  104  or to disconnect the components from each other, such as to interchange the interfaces  102 ,  104 , by accessing the locking/unlocking element  132  via the aperture  130 , such as with a tool inserted through the aperture  130 . The aperture  130  may extend through an entire thickness of the body  114  or may be limited to a single side of the body  114 , for example an upwardly or outwardly facing side. Other mechanisms or procedures for locking/unlocking the interfaces are likewise contemplated. 
     In embodiments, an engagement stop  134  may be provided at the end of the protruding portion opposite the stop-engaging surface  127 . The engagement stop  134  may form an engagement or connection with an end portion of the receiving channel  123 . In embodiments, the engagement stop  134  may be pre-tensioned in a direction such that the protruding portion  124  is biased against disengagement from the receiving portion. The engagement stop  134  may be pre-tensioned downwardly to tension the unlocking element  132  into the detent  142 , thereby preventing unintentional disengagement of the first and second attachment components  102 ,  104 . 
     The bias may increase friction between the protruding and receiving portions so as to resist unintentional disengagement. It will be understood that the described embodiments of the attachment components including the stop-engaging surface  127 , receiving channel  123 , terminal  152 , unlocking element  132 , detent  142 , and the engagement stop  134 , as with other elements of the disclosure, are merely exemplary and are not limiting. Additional mechanisms for attaching the interfaces  102 ,  104  are contemplated; for example, adhesive material may be applied to the junction  112  after the locking parts  124 ,  122  have been connected to ensure that the first and second attachment interfaces do not detach. 
     By providing corresponding protruding and receiving portions  124 ,  122 , the first and second attachment interfaces  102 ,  104  may be interchanged as necessary to provide a reliable and robust attachment between any desired and/or suitable components, which may be matched and/or interchanged with greater ease. If a cable must be attached to a strap, the interchangeable attachment device  100  of the disclosure advantageously allows attachment interfaces  102 ,  104  to simply and intuitively connect the cables and straps without the necessity and burden of providing and/or matching specific attachments or terminals for each component. The interchangeable attachment device  100  is not limited to attaching via corresponding protruding and receiving portions, but rather may attach via any suitable attachment mechanism. 
     The interchangeable attachment device  100  may attach a first component, such as a cable, to a second component, such as a strap, using a unitary flexible tab that attaches to a strap, for example by hook-and-loop fastener or any other suitable fastener, and defines a cable guide through a thickness of the tab, allowing a cable to slidably engage the tab through the guide. Other attachment systems for facilitating the attachment of two components are likewise envisioned within the disclosure. 
     The second attachment interface  104  may comprise a locking or attachment portion  120  arranged to attach to or lock a second component, such as straps  106 ,  108 . The locking portion  120  may be arranged to attach to any suitable component. In some embodiments, the locking portion  120  may be arranged for locking to straps; in others, the locking portion  120  may be arranged for attaching to a frame component; in others, the locking portion  120  may be arranged for attaching to a cable. The locking portion  120  may be arranged for attaching in any suitable manner to any suitable component and is not limited to the described embodiments. 
     In an embodiment, the locking portion  120  may be arranged to attach at end portions of the first and second straps  106 ,  108 . The locking portion  120  may comprise an overmolded portion comprising for example a thermoplastic material arranged to grip or clamp the straps  106 ,  108 . In certain embodiments, the overmolded portion may extend or penetrate a distance into the straps  106 ,  108 , thereby non-removably attaching to the straps  106 ,  108 . In other embodiments, the overmolded portion may be configured to removably attach to the straps  106 ,  108 . The overmolded portion may comprise any suitable material, including polymeric materials, and may be arranged to be rigid or resilient. The straps may have fibers or protruding features (hook or loop material, collectively referred to herein as “hook-and-loop material”) that interlock with material of the overmolded portion. In embodiments, the plastic material of the overmolded portion is different than a material forming the straps  106 ,  108  and is configured or chosen to interlock with the material forming the straps  106 ,  108 , which may be formed of different material from each other. 
     By locking the first and second straps  106 ,  108  at the locking portion  120 , the second attachment interface  104  can securely retain the first and second straps  106 ,  108  relative to the interface  104 , with the first and second straps  106 ,  108  serving a suitable purpose in a device, such as dynamic force straps in an orthopedic device. Alternatively, the first and second straps  106 ,  108  may advantageously serve to engage with and attach to a component, for example a textile strap. The first and second straps  106 ,  108  may comprise hook-and-loop material on an inward-facing and/or outward-facing surface suitable for engaging and grasping the textile material of a distinct strap, thereby securely attaching the textile strap to the attachment interface  104  through the hook-and-loop attachment. In embodiments, the first and second straps  106 ,  108  are configured to extend over opposed surfaces of the textile strap to surround and securely retain the textile strap relative to the attachment interface  104 . 
     By the term “overmolded,” it is intended to represent a process where a single part is created using two or more different materials in combination. Typically the first material, sometimes referred to as the substrate, is partially or fully covered by subsequent materials (overmold materials) during the manufacturing process. The substrate can include: a machined metal part, a molded plastic part, a textile, or even an existing product like threaded inserts, screws, or electrical connectors. It is the substrate that becomes a single continuous part with the material molded over it and composed of chemically bonded and often mechanically interlocked materials of separate types. 
     A distinct structure, as in the “overmold,” is created when an overmolding process is employed. Some examples include a first plastic overmolding a second plastic having different properties from the first plastic. A first rigid plastic substrate may be molded, and then another rigid plastic is molded over or around the substrate to provide a different property or color. In another example, a first rigid plastic substrate is molded, and then a soft rubber or thermoplastic elastomer is molded onto or around the substrate to provide a softer grip over the rigid part. 
     In typical processes of overmolding, the substrate material or part is placed into an injection molding tool, at which point the overmold material is shot into, onto, or around the substrate. When the overmold material cures or solidifies, the two materials become joined together as a single part. The substrate and overmold material interlock in some mechanical capacity. This way, the two materials will not only be bonded together chemically, they will also be held together physically. 
     In the instance of the straps, the textile or other material forming the straps may interlock with the second interface  104  material overmolding the straps. In yet other embodiments, the locking portion  120  may comprise D-rings configured for slidably engaging the straps  106 ,  108 . The locking portion  120  may comprise teeth that extend a di stance into and engage the straps  106 ,  108 . In embodiments, the teeth may be arranged to disengage by providing a hinge portion. 
     The straps  106 ,  108  may comprise any suitable configuration and may define any suitable feature. In an embodiment, the straps  106 ,  108  may comprise fastener material  109  along a surface and anti-attachment material  111  along another surface. In the embodiment of  FIG. 1 , the fastener material  109  may be a hook-and-loop-type fastener. In an embodiment, the straps  106 ,  108  may be arranged with fastener material  109  on outwardly facing sides thereof (i.e. a side of each strap  106 ,  108  that faces away from the other strap) such that the straps  106 ,  108  do not lock to each other. The straps  106 ,  108  may be arranged to bend away from each other and from the second attachment interface  104  flexibly and may be arranged with different sizes and shapes, this enabling the straps  106 ,  108  to at least be suitable for use and cooperation with a variety of different components or devices. The straps  106 ,  108  may further comprise one or more layers which define a thickness T 106 , T 108 , which may be the same or a different thickness, and which may vary or be uniform over a length of the strap. 
     The second attachment interface  104  may be arranged in any suitable configuration. In an embodiment, the body  114  may extend a length sufficient to allow multiple components, such as straps, to be attached at the locking portion  120  side by side rather than in a stacked or layered arrangement. The locking portion  120  may additionally be arranged to face a different direction; the second component, such as the straps  106 ,  108 , may be arranged to attach at the locking portion  120 , or multiple locking portions, at different portions. The straps may connect to the second attachment interface  120  at right angles from one another, for example at a T-shaped junction. The locking portion or portions  120  may face away from the receiving portion  122  in any suitable angle or shape, and the interchangeable attachment device  100  is not limited to the embodiments discussed but can take any suitable configuration. 
     In an embodiment, the locking portion  120  may be interchangeable on the second attachment interface  104 . The locking portion  120  may define a protruding and/or receiving portion arranged to cooperate with a corresponding locking or receiving portion on the second attachment interface  104  as described in relation to the interfaces  102 ,  104 . This advantageously allows different components, such as straps, to be attached to a single attachment interface  104  without defining or reconfiguring multiple types of interfaces. 
     The body  114  of the second attachment interface  104  may define a plurality of apertures through at least a thickness of the body  114 . Certain of the apertures  129  may be arranged to extend a distance to show a portion of the second component, such as the straps  106 ,  108 . The straps  106 ,  108  may comprise indicia arranged to be visible through the apertures  129 , enabling proper attachment of the straps  106 ,  108  by the locking portion  120  and confirmation of proper attachment. Other apertures  128  may extend continuously through an entirety of the body  114 . The apertures  128  may be arranged to extend closer to an end portion of the interface  104  while the apertures  129  may be arranged to extend closer to the strap portions  106 ,  108 . The apertures  128  may advantageously reduce a weight and cost of the interchangeable attachment device  100 , or may define a better grip, or may improve aesthetics, and/or may additionally allow a user to ascertain that the straps  106 ,  108  have not been inserted into the body  114  too far. 
     The interchangeable attachment device  100  may further define additional features and components. Some of the additional features may be arranged for facilitating the simplicity, intuitiveness, reliability, and robustness of the attachment between attachment interfaces. In an embodiment, the first and/or the second attachment interface  102 ,  104  may define within a portion thereof an elastic segment. The elastic segment may be arranged to provide flexibility and/or elasticity when the components are in the attached configuration or being attached. In an embodiment, the elastic segment may provide an easier attachment by allowing a user or manufacturer to more easily align the locking parts, for example, by bending one or more interfaces as needed, for inserting the protruding portion  124  or for disengaging the interfaces using the locking/unlocking mechanism. 
     In other embodiments, the first and/or second attachment interfaces  102 ,  104  may support features such as adjustment features. In the embodiment of  FIG. 1  in which the first attachment interface  102  is arranged to cooperate with a cable of a dial-tensioning device, the first attachment interface  102  may support and cooperate with a dial tensioner to cooperate with and adjust a length of the cable. In embodiments where the second attachment interface  104  is arranged to cooperate with one or more straps  106 ,  108 , the second attachment interface  104  may define an adjustment feature to adjust a length or tension in the straps  106 ,  108 . 
       FIGS. 6-8  illustrate an alligator attachment  200  arranged for extending a strap or providing an engaging portion for securing to a surface of a sleeve, opposing strap or other surface adapted for receiving the attachment  200 . The attachment  200  includes a first surface  202  having a first texture or functional surface, and a second surface  204  having a second texture or functional surface. For example, the first surface  202  may be a brushed or unbroken loop material or a textile material, whereas the second surface  204  may be hook material for coupling to a unbroken loop material. Other fastening means may be contemplated and the disclosure is not limited to hook material. 
     The attachment  200  has a strip or elongate section  206  and a head section  208 , with a flap  250  connected to the elongate section  206 . The attachment  200  is arranged to secure to a strap  260  with a cooperating surface in which at least the first surface  202  interlocks, as in hook and loop. As shown, the first surface  202  extends along an entirety of the elongate and head sections  206 ,  208 , and the second surface  204  extends along an entirety of the elongate and head sections  206 . Alternatively, the first and second surfaces  202 ,  204  may be arranged in segments in that they are arranged short of the entire length or width of the first and second surfaces  202 ,  204 . 
     The flap  250  may be secured along any point of the elongate section  206 . In the illustrated embodiment, the flap  250  is generally stitched or otherwise secured to the elongate section  206  mid-height from the head section  208  at a junction  252 . It is preferred that the flap  250  is secured below the head section  208 , as it is generally cut or formed to extend parallel to elongate section  206 . While the flap  250  may have a preferred width matching the width of the elongate section  206 , it may likewise be formed wider or narrower than the width of the flap  250  depending on the width of the strap  260  upon which the attachment  200  is secured. An inner surface of the flap  250 , not shown, may be arranged similarly as the inner or first surface  202  of the elongate section  206 . 
     A traction element  210  may be provided along the head section  208 . The head section  208  has a profile forming a tip  212  and a sloped edge  214 . The traction element  210  corresponds to the profile of the head section  208  with first and second ends  220 ,  222  on opposed sides of the head section  208 , generally along a line  228  separating the head section  208  from the elongate section  206 . The traction element  210  is spaced away by a distance  224  from a profile or peripheral edge  226  of the head section  208 . 
     While the elongate section  206  and the head section  208  may be continuous with one another and have a substantially flexible configuration in that they conform to a shape in which they bend, the traction element  210  is preferably rigid or semi-rigid in comparison to the elongate section  206 . As shown, a same material may extend across continuously without interruption across the first and second surfaces  202 ,  204  of the attachment  200 , across both the elongate and head sections  206 ,  208 . Alternatively, different materials may define the first and second surfaces  202 ,  204  at designated locations, either offering different fastening properties or used to inhibit or increase flexibility at such designated locations. 
     The traction element  210  is arranged to offer a raised profile  217  protruding outwardly from the head section  208  to better enable a user to grasp the attachment  200 . In addition to the raised profile  217 , the traction element  210  may have additional ergonomic features with first and second slopes  216 ,  218  leading to the raised profile  217 . The raised profile  217  may form a depression  230  adapted for leading a user&#39;s finger to grasp the traction element  210  at a predetermined location. 
     The traction element  210  is preferably overmolded onto the head section  208 . The traction element  210  may be formed from a molded polymeric material whereas the first surface  202  of the head section  208  is formed from a textile or generally understood as a loop material, indicated as a material in which a series of hooks may engage, or a hook material. The first surface  202  can be formed from any type of flexible material, textile or polymeric, and is not limited to loop material. By being overmolded, the traction element  210  interlocks with the first surface  202 , thereby removing the necessity of gluing or using other means to secure the traction element  210  to the first surface  202 , although other means for securing the traction element  210  to the first surface  202  are not eliminated from use according to the disclosure. The traction element  210  is arranged so as to be sufficiently pliable to yield to bending of the head section  208 , so as not to inhibit flexibility of the attachment  200 . 
     Unlike in conventional alligator attachments having first and second sections with fastener material, such as hook material, adapted to clamp onto a strap surface having loop material, the attachment  200  consists of a single section comprising the elongate section and the head section  206 ,  208 . The traction element  210  is arranged with the spacing  224  from the profile  226  to not reach all the way to the border or periphery of the head section  208 . This prevents the head section  208  of the attachment from lifting up from a substrate upon which the second surface  204  is secured, such as a strap when the strap is bent. This arrangement also allows for a more solid connection of a hook-and-loop engagement or fastener system, and allows the traction element  210  to exhibit more flexibility than conventional traction elements that extend to or wrap about a periphery of a head section. 
     Due to the ergonomic form of the traction element  210 , less material can be used, which in turn reduces stiffness while offering a user improved handling of the traction element  210 . By using less material and a reduced footprint over the head section  208 , the head section  208  is further prevented from lifting up from the surface that it engages. To aid the user, the traction element  210  may be colored differently from the first surface  202  to provide for contrast. 
     The interchangeable attachment system embodiments of the disclosure advantageously provide an improved attachment between components, the attachment being more cost-effective and intuitive for users by providing interchangeable attachment interfaces suitable for use with different components and providing a reliable and robust attachment to each other. The interchangeable attachment system embodiments of the disclosure thus improve compliant use and reduce costs of manufacturing by mitigating the need to provide component-specific attachment interfaces not only for each component but also for each type of attachment between a limitless number of different components that may be used in a device, such as an orthopedic, prosthetic, or medical device. 
     It is to be understood that not necessarily all objects or advantages may be achieved under any embodiment of the disclosure. Those skilled in the art will recognize that an interchangeable attachment system may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without achieving other objects or advantages as taught or suggested herein. 
     The skilled artisan will recognize the interchangeability of various disclosed features. Besides the variations described herein, other known equivalents for each feature can be mixed and matched by one of ordinary skill in this art to build and use an attachment system under principles of the present disclosure. It will be understood by the skilled artisan that the features described herein may be adapted to other methods and types of attachment systems and devices. 
     Although this disclosure describes certain exemplary embodiments and examples of an attachment system, it will be understood by those skilled in the art that the present disclosure extends beyond the specifically disclosed attachment systems to other alternative embodiments and/or uses of the disclosure and obvious modifications and equivalents thereof, including other types and components of various devices, including orthopedic, prosthetic, medical, and otherwise. It is intended that the present disclosure should not be limited by the disclosed embodiments described above and may be extended to other applications that may employ the features described herein.