Patent Publication Number: US-2021177108-A1

Title: Attachment system for watchband

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/986,540, filed May 22, 2018, which claims the benefit of U.S. Provisional Application No. 62/516,043, entitled “ATTACHMENT SYSTEM FOR WATCHBAND,” filed Jun. 6, 2017, the entirety of each of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present description relates generally to securement of wearable devices, and, more particularly, to attachment systems for watchbands. 
     BACKGROUND 
     Some electronic devices may be removably attached to a user. For example, a wristwatch or fitness/health tracking device can be attached to a user&#39;s wrist by joining free ends of a watchband together. In many cases, watchbands may have limited fit adjustment increments available. For example, some bands have an incrementally user-adjustable size (e.g., a buckling clasp, pin and eyelet, etc.) whereas other bands have a substantially fixed size, adjustable only with specialized tools and/or expertise (e.g., folding clasp, deployment clasp, snap-fit clasp, etc.). Other bands may be elasticated expansion-type bands that stretch to fit around a user&#39;s wrist. The degree of comfort and securement of the electronic device to the user can depend on the function and arrangement of the watchband. 
     Consumer products such as watches, cameras, phones, purses, and glasses may include one or more accessories attached thereto. The manner in which they are attached may be widely varied. However, they typically suffer from similar, if not the same, drawbacks. For example, many consumer products typically do not include user-friendly attachment systems. Some may require special tools and others may even require taking the consumer product into a shop in order to remove, fix or replace the accessories. Furthermore, even when products have user oriented attachment mechanisms, they may not provide adequate retention force. Even if the retention force is adequate, the mechanism used may be quite robust and large thereby adversely affecting the elegance of the consumer product. 
     In one example, wristwatches typically include a case and a band. The case carries the components or mechanisms of the wristwatch including the face. The band extends away from the case so that it can wrap around the wrist of a user. The band may be integral with the case. However, in most cases, the band is a separate part that is attached to the case. For example, the case may include a pin that captures the band thereby attaching the band to the case. In order to detach the band from the case, the pin needs to be removed. In some instances, band removal can be accomplished with a special tool. However, in many cases, the user may need to visit a specialty store or have the assistance of technician in order to remove the band. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Certain features of the subject technology are set forth in the appended claims. However, for purpose of explanation, several embodiments of the subject technology are set forth in the following figures. 
         FIG. 1  is a perspective view of a watch, in accordance with some embodiments of the present disclosure. 
         FIG. 2  is a side view of a watch housing, in accordance with some embodiments of the present disclosure. 
         FIG. 3  is a rear view of a watch housing, in accordance with some embodiments of the present disclosure. 
         FIG. 4  is an exploded perspective view of a watch housing, in accordance with some embodiments of the present disclosure. 
         FIG. 5  is a perspective view of a watch housing and a watchband connector, in accordance with some embodiments of the present disclosure. 
         FIG. 6  is a sectional view of a watch housing and a watchband connector of the section A-A of  FIG. 3 , in accordance with some embodiments of the present disclosure. 
         FIG. 7  is a sectional view of the watch housing and the watchband connector of  FIG. 6 , in accordance with some embodiments of the present disclosure. 
         FIG. 8  is a sectional view of the watch housing and the watchband connector of  FIG. 6 , in accordance with some embodiments of the present disclosure. 
         FIG. 9  is a sectional view of a watch housing and a watchband connector, in accordance with some embodiments of the present disclosure. 
         FIG. 10  is a sectional view of a watch housing and a watchband connector, in accordance with some embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description set forth below is intended as a description of various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology may be practiced. The appended drawings are incorporated herein and constitute a part of the detailed description. The detailed description includes specific details for the purpose of providing a thorough understanding of the subject technology. However, it will be clear and apparent to those skilled in the art that the subject technology is not limited to the specific details set forth herein and may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring the concepts of the subject technology. 
     Wearable electronic devices, such as watches, can be provided with an attachment system for connecting and releasing a removable module that interfaces with some portion of the electronic device. For example, a watch can include watchbands that connect to a watch housing and secure the watch housing to a wrist of a user. The watchbands engage with a related or corresponding module, recess, aperture, or component of the watch housing. 
     Attachment systems for such modules are desired to provide secure retention, ease of release, and aesthetic qualities. For example, an attachment system for a watch is desired to retain and selectively release a watchband without adversely affecting look and feel of the watch. As the parts for such a system can be small, precise fabrication with low tolerances are preferred so the parts are responsive to operation by a user. 
     A button can be provided for retaining and releasing an attachment unit of a watchband from a channel of a watch housing. Where the button is made from multiple parts, the complexity and cost of fabrication can be relatively high. In some designs, the multiple parts of the button must be assembled within the watch housing, which is an additional step that introduces a risk of flawed assembly. The interconnection between parts (e.g., snap fit) can lead to poor performance as actuation of one part can be improperly translated to other parts. Furthermore, the multiple parts can shift relative to each other, such that aesthetic features, such as surface alignment with respect to the watch housing, can be difficult to achieve with precision. 
     Embodiments of the present disclosure provide a unibody button for retaining and releasing an attachment unit of a watchband from a channel of a watch housing. The button is moveably contained between the watch housing and a rear cover, against which the button is biased. With a unibody construction, the button is able to be made with small tolerances. Fabrication of a small unibody part is more straightforward and less expensive than multiple constituent parts. The total number of parts is reduced, thereby simplifying assembly. By eliminating interfaces between constituent parts of a button, activity (e.g., forces, biasing, and engagement) at one portion of the button translates directly to other portions thereof. Assembly tolerances and subsequent cosmetic variation of the button to the surrounding surfaces are reduced due to elimination of the button assembly requirement. 
       FIG. 1  illustrates a watch  10  including a watch housing  30  that is useable with an attachment unit  12  of an attachment system according to one or more embodiments of the present disclosure. It will be appreciated that the teachings relating to a watch can be applied to other electronic devices, including wearable and/or portable computing devices. Examples include cell phones, smart phones, tablet computers, laptop computers, timekeeping devices, computerized glasses and other wearable devices navigation devices, sports devices, accessory devices, health-monitoring devices, medical devices, wristbands, bracelets, jewelry, and/or the like. 
     According to some embodiments, one of the components included in the watch  10  can be one or more I/O systems. For example, the watch  10  can include a touchscreen  20  configured to output various information about the watch  10 . The touchscreen  20  of the watch  10  can also be configured to receive input. The watch  10  can also have other input and output mechanisms. For example, the watch  10  can include or interface with one or more buttons, a crown, keys, dials, trackpads, microphones and the like. 
     The watch  10  can include a watch housing  30  and one or more attachment units  12  capable of being removably coupled to a main body  14  of the watch housing  30 . The watch housing  30  serves to surround a peripheral region of the watch  10  as well as support the internal components of the watch  10  in their assembled position. For example, the watch housing  30  encloses and supports various internal components (including for example integrated circuit chips, processors, memory devices and other circuitry) to provide computing and functional operations for the watch  10 . 
     The watch  10  can utilize a watchband  18  for attaching the watch  10  to a wrist. For example, as shown in  FIG. 1 , the watchband  18  can include a first band strap  62  attached to a first attachment unit  12  of the watch  10  and a second band strap  64  attached to a second attachment unit  12  of the watch  10 . In some embodiments, free ends of the first band strap  62  and the second band strap  64  can be configured to be releasably attached or secured to one another using a clasp  66  or other attachment mechanism to form a loop. This loop can then be used to attach the watch  10  to a user&#39;s wrist. 
     Although a single attachment unit  12  is discussed herein, a plurality of attachment units  12  can be coupled to the watch housing  30 . When multiple attachment units  12  are used, as shown in  FIG. 1 , the watch housing  30  can have a band retaining feature (e.g., channel  16 , latch, clip, recess, lock or other such coupling node) on a first side and a second side of the main body  14 . While the band retaining feature of  FIG. 1  is shown as a channel, it will be understood that other retention mechanisms can be applied. The channel  16  on the first side of the main body  14  of the watch housing  30  can receive one of the attachment units  12  and the channel  16  on the second side of the main body  14  of the watch housing  30  can receive another attachment unit  12 . The attachment units  12  can have a same or different size and/or shape, wherein the size and/or shape corresponds to a size and/or shape of the respective channel  16 . 
     According to some embodiments, for example as shown in  FIG. 2 , the main body  14  includes one or more channels  16  that mechanically engage a corresponding attachment unit  12 . The channels  16  on the main body  14  include an opening while the attachment unit  12  includes a lug that fits within the opening. The opening can be configured in a variety of different shapes and orientations. Further, the opening is configured to removably receive the lug such as will be described in detail below. 
     As further illustrated in  FIG. 2 , the watch  10  can include components for performing various functions, including interacting with a user. For example, the watch  10  can include components for interacting with a user. The touchscreen  20  can provide visual (e.g., image or video) output for the watch  10 . The touchscreen  20  may also provide an input surface for one or more touch input devices such as a touch sensing device, force sensing device, temperature sensing device, and/or a fingerprint sensor. The touchscreen  20  may be any size suitable for inclusion at least partially within the housing of the watch  10  and may be positioned substantially anywhere on the watch  10 . 
     The watch  10  can further include one or more other user interfaces  76  for receiving input from and/or providing output to a user. For example, one or more buttons, dials, crowns, switches, or other devices can be provided for receiving input from a user. The user interface  76  can include a speaker, a microphone, and/or a haptic device. A haptic device can be implemented as any suitable device configured to provide force feedback, vibratory feedback, tactile sensations, and the like. For example, in one embodiment, the haptic device may be implemented as a linear actuator configured to provide a punctuated haptic feedback, such as a tap or a knock. 
     As further shown in  FIG. 2 , the watch  10  includes one or more processing units  72  that include or are configured to access a memory having instructions stored thereon. The instructions or computer programs may be configured to perform one or more of the operations or functions described with respect to the watch  10 . The processing units  72  can be implemented as any electronic device capable of processing, receiving, or transmitting data or instructions. For example, the processing units  72  may include one or more of: a microprocessor, a central processing unit (CPU), an application-specific integrated circuit (ASIC), a digital signal processor (DSP), or combinations of such devices. As described herein, the term “processor” is meant to encompass a single processor or processing unit, multiple processors, multiple processing units, or other suitably configured computing element or elements. The memory can store electronic data that can be used by the watch  10 . For example, a memory can store electrical data or content such as, for example, audio and video files, documents and applications, device settings and user preferences, timing and control signals or data for the various modules, data structures or databases, and so on. The memory can be configured as any type of memory. By way of example only, the memory can be implemented as random access memory, read-only memory, Flash memory, removable memory, or other types of storage elements, or combinations of such devices. 
     As further shown in  FIG. 2 , the watch  10  may include a communication component  74  that facilitates transmission of data and/or power to or from other electronic devices across standardized or proprietary protocols. For example, a communication component  74  can transmit electronic signals via a wireless and/or wired network connection. Examples of wireless and wired network connections include, but are not limited to, cellular, Wi-Fi, Bluetooth, infrared, RFID and Ethernet. 
     As further shown in  FIG. 2 , the watch  10  may also include one or more sensors  78 , such as biosensors, positioned substantially anywhere on the watch  10 . The one or more sensors  78  may be configured to sense substantially any type of characteristic such as, but not limited to, images, pressure, light, touch, force, temperature, position, motion, and so on. For example, the sensor(s)  78  may be a photodetector, a temperature sensor, a light or optical sensor, an atmospheric pressure sensor, a humidity sensor, a magnet, a gyroscope, an accelerometer, and so on. In other examples, the watch  10  may include one or more health sensors. In some examples, the health sensors can be disposed on a bottom surface of the housing of the watch  10 , such as near the rear cover  22 . The one or more sensors  78  can include optical and/or electronic biometric sensors that may be used to compute one or more biometric characteristic. A sensor  78  can include a light source and a photodetector to form a photoplethysmography (PPG) sensor. Light can be transmitted from the sensor  78 , to the user, and back to the sensor  78 . For example, the main body  14  and/or the rear cover  22  can provide one or more windows  90  (e.g., opening, transmission medium, and/or lens) to transmit light to and/or from the sensor  78 . The optical (e.g., PPG) sensor or sensors may be used to compute various biometric characteristic including, without limitation, a heart rate, a respiration rate, blood oxygenation level, a blood volume estimate, blood pressure, or a combination thereof. One or more of the sensors  78  may also be configured to perform an electrical measurement using one or more electrodes. The electrical sensor(s) may be used to measure electrocardiographic (ECG) characteristics, galvanic skin resistance, and other electrical properties of the user&#39;s body. Additionally or alternatively, a sensor  78  can be configured to measure body temperature, exposure to UV radiation, and other health-related information. 
     As further shown in  FIG. 2 , the watch  10  may include a battery  80  that is used to store and provide power to the other components of the watch  10 . The battery  80  may be a rechargeable power supply that is configured to provide power to the watch  10 . The watch  10  may also be configured to recharge the battery  80  using a wireless charging system. 
       FIG. 3  illustrates a bottom view of the watch  10  of  FIG. 1  according to one or more embodiments of the present disclosure. A rear cover  22  or multiple rear covers can be provided over a portion of the main body  14 . The button  34  can be disposed on an underside of the main body  14 . Alternatively or additionally, the button  34  can be disposed or positioned on a top side of the main body  14 . The rear cover  22  can surround at least a portion of one or more buttons  34 . According to some embodiments, the button  34  can be used to release a locking mechanism of the attachment unit  12  from the channel  16 . Actuation of the button  34  releases the attachment unit  12 , which enables the attachment unit  12  to be removed from the channel  16 . 
     The rear cover  22  can cover a substantial portion of the main body  14  of the watch  10 . For example, the rear cover  22  can cover a majority of the main body  14  on one side thereof (e.g., more than 50%, 60%, 70%, 80%, or 90% or up to 100% of a surface area on a side of the main body  14 ). The rear cover  22  can extend approximately from one channel to another channel that are both within the main body  14 . The rear cover  22  can provide an entirety of the surface of the housing that is contacted by the wrist of the user when the watch  10  is worn. 
     The rear cover  22  can include one or more components  88  that provide communication, access, or functions on or through the rear cover  22 . The components  88  can include one or more windows  90 , one or more electrodes  92 , and/or one or more modules  94 . While the components  88  of  FIG. 3  are represented as squares aligned in a grid pattern, it will be understood that the components  88  can be of any size, shape, and/or arrangement. For example, the components  88  can be square, rectangular, polygonal, round, curved, arcuate, circular, semi-circular, flat, or another shape. The components  88  (e.g., windows  90 , electrodes  92 , and/or modules  94 ) can be the same size, different sizes, the same shape, or different shapes. The components  88  (e.g., windows  90 , electrodes  92 , and/or modules  94 ) can be distributed in a pattern or another arrangement along the surface of the rear cover  22 . At least a pair of the components  88  of one type (e.g., windows  90 , electrodes  92 , and modules  94 ) can be separated from each other by components  88  of another type. One or more of the components  88  (e.g., windows  90 , electrodes  92 , and modules  94 ) can partially or entirely surround another one or more of the components  88  (e.g., windows  90 , electrodes  92 , and modules  94 ). For example, at least some of the electrodes  92  can partially or entirely surround one or more of the windows  90  and/or modules  94 . At least some of the windows  90  can partially or entirely surround one or more other windows  90 . For example, one or more central windows  90  can be used to transmit light in one direction, and other surrounding windows  90  can be used to transmit light in another direction. Additionally or alternatively, the windows  90  can partially or entirely surround one or more of the electrodes  92  and/or modules  94 . The components  88  can extend along an inner and/or outer surface of the rear cover  22  and/or extend into or through the width of the rear cover  22  (e.g., between and to opposing sides of the rear cover  22 ). 
     The rear cover  22  can provide one or more windows  90  forming optical pathways to transmit light to and/or from a sensor within the main body  14 . With light transmitted through the windows  90 , an optical (e.g., PPG) sensor or sensors can be used to compute various biometric characteristics including, without limitation, a heart rate, a respiration rate, blood oxygenation level, a blood volume estimate, blood pressure, or a combination thereof. The windows  90  can form an opening, a transmission medium, an optical filter, and/or a lens. It will be appreciated that any number of windows  90  can be provided. One or more windows  90  can provide transmission of light from a light-emitting device within the main body  14 . One or more windows  90  can provide transmission of light to a light-detecting device (e.g., sensor) within the main body  14 . The windows  90  can be of any size, shape, and arrangement. For example, the windows  90  can be arranged to align with a sensor and/or a target region or regions of the user when the watch is worn by the user. 
     The rear cover  22  can provide one or more electrodes  92  to provide an electrically conductive pathway through or along the rear cover  22 . The electrodes  92  can be operated to perform an electrical measurement, for example, to measure electrocardiographic (ECG) characteristics, galvanic skin resistance, and other electrical properties of the user&#39;s body and/or the environment. It will be appreciated that any number of electrodes  92  can be provided. Each electrode  92  can be insulated from other electrodes  92  and/or other components of the watch. One or more electrodes  92  can operate as a first terminal, and one or more electrodes  92  can operate as an additional terminal. The electrodes  92  can be of any size, shape, and arrangement. For example, the electrodes  92  can be arranged to align with a target region or regions of the user when the watch is worn by the user. 
     The rear cover  22  can provide one or more modules  94  providing additional functionality. The one or more modules  94  can provide of facilitate measurements of body temperature, exposure to UV radiation, and other health-related information. The one or more modules  94  can provide of facilitate measurements of body temperature, exposure to UV radiation, and other health-related information. The one or more modules  94  can be configured to provide or facilitate detection of images, pressure, light, touch, force, temperature, position, motion, and so on. The one or more modules  94  can include or facilitate operation of a temperature sensor, a light or optical sensor, an atmospheric pressure sensor, a humidity sensor, a magnet, a gyroscope, an accelerometer, and so on. The one or more modules  94  can include an opening extending partially or entirely through the rear cover  22  to provide exposure to an external environment, for example, for measurements. 
       FIG. 4  illustrates an exploded perspective view of the watch  10  of  FIG. 1  according to one or more embodiments of the present disclosure. The button  34  can be positioned between the rear cover  22  and the main body  14 . By providing the rear cover  22  and the main body  14  on opposite sides of the button  34 , the watch  10  can be assembled to contain the button  34 . As such, the button  34  can be a unibody structure, rather than an assembly of parts that are assembled within the watch  10 . As used herein, a unibody structure is one that is integrally formed of a single piece. For example, the button  34  can be a monolithic structure. By providing a unibody button  34 , the button  34  does not contain dimensional variations that occur in assembled parts. Accordingly, the unibody button  34  can be fabricated to more precise and consistent dimensions. This allows the unibody button  34  to more accurately match the dimensions of the main body  14  and the rear cover  22  into which the unibody button  34  is placed. 
     According to some embodiments, the button  34  is aligned with a housing opening  26  of the main body  14 . The housing opening  26  extends through the main body  14  at least to the channels  16 . In some embodiments, the housing opening  26  is positioned within the channel  16  such that the locking mechanism of the attachment unit  12  is aligned with the housing opening  26  when the sides of the attachment unit  12  are flush or substantially flush with respect to the channel  16  and/or one or more sidewalls of the main body  14 . For example, the channel  16  of the main body  14  is configured to receive either a proximal end or a distal end of the attachment unit  12 . Once either the proximal end or the distal end of the attachment unit  12  has been received by the channel  16 , the attachment unit  12  can slide or move within the channel  16  until the locking mechanism of the attachment unit  12  expands into, engages with, or otherwise enters the housing opening  26  contained within the main body  14 . 
     According to some embodiments, the button  34  is aligned with a cover opening  24  of the rear cover  22 . The cover opening  24  extends through the rear cover  22  to opposite surfaces thereof. The rear cover  22  can be placed on the main body  14  so that the button  34  is secured within the housing opening  26  and the cover opening  24 . The user can access the button  34  at the cover opening  24  of the rear cover  22 . The button  34  can be movable through at least part of the cover opening  24  and the housing opening  26  while the rear cover  22  is affixed to the main body  14 . 
     The housing opening  26  and the cover opening  24  can provide one or more of a variety of shapes and sizes to accommodate portions of the button  34 . For example, the shape and/or size of the housing opening  26  and the cover opening  24  can complement corresponding portions of the button  34 . The housing opening  26  and/or the cover opening  24  can have a cross-sectional shape that is round, rectangular, oval, oblong, lozenge-shaped, and/or polygonal. The housing opening  26  and the cover opening  24  can have the same or different shapes and/or sizes. According to some embodiments, the cover opening  24  is larger than the housing opening  26  to accommodate a fingernail and/or tool to actuate the button  34 . Separate housing openings  26  of a given main body  14  can have the same or different shapes and/or sizes. Separate cover openings  24  of a given rear cover  22  can have the same or different shapes and/or sizes. For any given housing opening  26  or cover opening  24 , the cross-sectional shape and/or size can be the same or vary along the depth thereof. 
     According to some embodiments, for example as shown in  FIG. 5 , the attachment unit  12  can be laterally inserted into the main body  14  of the watch  10 . As such, the attachment unit  12  can be configured to slide relative to the main body  14  of the watch  10 . Alternatively or additionally, the attachment unit  12  can be pressed, snap fit or otherwise forwardly inserted into the channel  16  of the main body  14 . Once inserted, the attachment unit  12  can be locked or otherwise secured within the main body  14 . For example, a locking mechanism (e.g., a lug) can engage at least the housing opening  26  within the channel  16 . 
       FIG. 6  illustrates a sectional view of the watch  10  of  FIG. 1  according to one or more embodiments of the present disclosure. The attachment unit  12  is shown within a channel  16 , which separates portions of the main body  14  from each other. According to some embodiments, for example as shown in  FIG. 6 , the button is moveably contained between the rear cover  22  and the main body  14 , which are coupled to each other. The cover opening  24  of the rear cover  22  is provided across from a housing opening  26  of the main body  14 , so that a continuous opening is provided from the channel  16  to an outer surface of the rear cover  22 . A locking mechanism (e.g., lug  8 ) of the attachment unit  12  engages within the housing opening  26  when aligned therewith. In this position, the attachment unit  12  is unable to move within or be removed from the channel  16  until the lug  8  is released form the housing opening  26 . 
     According to some embodiments, the button  34  comprises various regions. The regions of the button  34  are not distinctly separable, but rather regions of the unibody structure. The button  34  includes a rear portion  40  that can extend at least partially through the cover opening  24 . The rear portion  40  can be accessed by a user for actuation. In a rest position (e.g., when not actuated by a user), the rear portion  40  can be flush with a surface of the rear cover  22 . The rear portion  40  can form a spline within the rear cover  22  so that the surface of the rear portion  40  is continuous with the surface of the rear cover  22 . The rear portion  40  has a contour that matches a contour of the surface of the rear cover  22 . The button  34  further includes a channel portion  44  that can extend at least partially through the housing opening  26 . The channel portion  44  can engage the lug  8  of the attachment unit  12  when the button  34  is actuated. Between the rear portion  40  and the channel portion  44 , the button  34  includes a flange  42  for engaging other structures. 
     According to some embodiments, the rear portion  40  of the button  34  can include or be coupled to a cap (not shown). The cap can be of a different material and/or have a cosmetic feature that is different than that of the rear portion  40 . For example, the cap can cosmetically match a surface of the rear cover  22 . At least some of the cap extends outwardly toward or through the cover opening  24 . 
     The button  34  is biased to a rest position. According to some embodiments, the button  34  is biased so that the flange  42  is pressed against the rear cover  22 . One or more spring elements  46  can be provided between the button  34  (e.g., the flange  42 ) and the main body  14 . According to some embodiments, the spring elements  46  can include a coil spring, a compression spring, a leaf spring, a torsion spring, cantilever spring, or a structure of an elastic material. 
     The spring elements can bias the button  34  into the cover opening  24  or against the rear cover  22 . The spring elements  46  can also bias the button  34  away from the main body  14 , the housing opening  26 , and/or the lug  8  of the attachment unit  12 . The spring elements  46  apply a force to the button  34  at least when the button  34  is depressed by a user. The force can be normal to the cover opening  24 , so that the button  34  is radially aligned within the cover opening  24 , rather than deflected to one side thereof. The spring elements  46  can continue to apply a force to the button  34  when not depressed, so the button is maintained away from the lug  8 . Because the button  34  is a unibody structure, the position of every part of the button  34  is predictable when the spring elements  46  acts presses the flange  42  against the rear cover  22 . For example, the movement and position of the flange  42  is controlled based on the bias of the spring elements  46  and the limit provided by the rear cover  22 . Accordingly, the rear portion  40  and the channel portion  44  are moved and positioned in direct relation to the flange  42  where all parts are of a unibody structure. With this result, the entire button  34  can be sized and shaped to fit relative to the main body  14  and the rear cover  22  with lower tolerances than would be required with buttons of multiple assembled parts. 
       FIG. 7  illustrates a sectional view of the watch  10  of  FIG. 6  with the button actuated by a user according to one or more embodiments of the present disclosure. To release the attachment unit  12  from the channel  16 , the button  34  is actuated. When actuated, the button  34  can move so that the channel portion  44  of the button  34  moves towards and partially through the housing opening  26 . Actuation of the button  34  expels the lug  8  from the housing opening  26 . As shown in  FIG. 8 , this also enables the attachment unit  12  to once again freely move or slide within the channel  16  of the main body  14  or be pulled out from the front face of the channel  16 . For example, when actuated, the button  34  can move so that the channel portion  44  is flush with a surface of the channel  16 . The channel portion  44  can form a spline within the main body  14  so that the surface of the channel portion  44  is continuous with the surface of the channel  16 . The channel portion  44  has a contour that matches a contour of the surface of the channel  16 . When released, the button  34  can return to the rest position by action of the spring elements  46 . 
     According to some embodiments, for example as shown in  FIG. 9 , the button  34  is biased with one or more of a variety of spring elements. For example, one or more extension arms  52  can extend from the button  34  toward the main body  14 . The extension arms  52  can be parts of a continuous structure. The extension arms  52  can be integrated into the button  34 , for example by welding or overmolding. Each of the extension arms  52  is fixed a corresponding retention member  54  that is attached to the main body  14 . The extension arms  52  can be resilient, so that they tend to push against the retention members  54  and bias the button  34  against the rear cover  22 . 
     Other configurations for biasing the button  34  against the rear cover  22  are contemplated. For example, the button  34  can be biased against the rear cover  22  with a spring element that is connected to the button  34  and the rear cover  22 . The spring element can include a tension spring between the button  34  and the rear cover  22  that stretches when the button is depressed and applies a tension force on the button to bias it against the rear cover  22 . The spring element need not between the button  34  and the rear cover  22 . For example, the spring element can connect a side of the button  34  facing the channel  16  with a portion of the rear cover  22  that is outside the periphery of the button  34 . 
     According to some embodiments, for example as shown in  FIG. 10 , the button  34  and the cover opening  24  have complementary shapes that facilitate radial alignment of the button within the cover opening  24 . As shown in  FIG. 10 , the rear portion  40  of the button  34  can have a tapered cross-sectional dimension along a depth thereof. The cover opening  24  can also have a tapered cross-sectional dimension along a depth thereof. The shape for either can, for example, form a frustrum (e.g., frustoconical, etc.). The shape can be complementary so that the button  34  is radially aligned within the cover opening  24  by moving axially into the cover opening  24 . Where radial misalignment occurs, reentry into the cover opening  24  can restore proper alignment. Furthermore, engagement between the button  34  and the cover opening  24  can occur when a surface of the button  34  is flush with a surface of the rear cover  22 . 
     Accordingly, embodiments of the present disclosure provide a button (e.g., unibody button) for retaining and releasing an attachment unit of a watchband from a channel of a watch housing. The button is moveably contained between the watch housing and a rear cover, against which the button is biased. With a unibody construction, the button is able to be made with small tolerances. Fabrication of a small unibody part is more straightforward and less expensive than multiple constituent parts. The total number of parts is reduced, thereby simplifying assembly. By eliminating interfaces between constituent parts of a button, activity (e.g., forces, biasing, and engagement) at one portion of the button translates directly to other portions thereof. Assembly tolerances and subsequent cosmetic variation of the button to the surrounding surfaces are reduced due to elimination of the button assembly requirement. 
     A reference to an element in the singular is not intended to mean one and only one unless specifically so stated, but rather one or more. For example, “a” module may refer to one or more modules. An element proceeded by “a,” “an,” “the,” or “said” does not, without further constraints, preclude the existence of additional same elements. 
     Headings and subheadings, if any, are used for convenience only and do not limit the invention. The word exemplary is used to mean serving as an example or illustration. To the extent that the term include, have, or the like is used, such term is intended to be inclusive in a manner similar to the term comprise as comprise is interpreted when employed as a transitional word in a claim. Relational terms such as first and second and the like may be used to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. 
     Phrases such as an aspect, the aspect, another aspect, some aspects, one or more aspects, an implementation, the implementation, another implementation, some implementations, one or more implementations, an embodiment, the embodiment, another embodiment, some embodiments, one or more embodiments, a configuration, the configuration, another configuration, some configurations, one or more configurations, the subject technology, the disclosure, the present disclosure, other variations thereof and alike are for convenience and do not imply that a disclosure relating to such phrase(s) is essential to the subject technology or that such disclosure applies to all configurations of the subject technology. A disclosure relating to such phrase(s) may apply to all configurations, or one or more configurations. A disclosure relating to such phrase(s) may provide one or more examples. A phrase such as an aspect or some aspects may refer to one or more aspects and vice versa, and this applies similarly to other foregoing phrases. 
     A phrase “at least one of” preceding a series of items, with the terms “and” or “or” to separate any of the items, modifies the list as a whole, rather than each member of the list. The phrase “at least one of” does not require selection of at least one item; rather, the phrase allows a meaning that includes at least one of any one of the items, and/or at least one of any combination of the items, and/or at least one of each of the items. By way of example, each of the phrases “at least one of A, B, and C” or “at least one of A, B, or C” refers to only A, only B, or only C; any combination of A, B, and C; and/or at least one of each of A, B, and C. 
     It is understood that the specific order or hierarchy of steps, operations, or processes disclosed is an illustration of exemplary approaches. Unless explicitly stated otherwise, it is understood that the specific order or hierarchy of steps, operations, or processes may be performed in different order. Some of the steps, operations, or processes may be performed simultaneously. The accompanying method claims, if any, present elements of the various steps, operations or processes in a sample order, and are not meant to be limited to the specific order or hierarchy presented. These may be performed in serial, linearly, in parallel or in different order. It should be understood that the described instructions, operations, and systems can generally be integrated together in a single software/hardware product or packaged into multiple software/hardware products. 
     In one aspect, a term coupled or the like may refer to being directly coupled. In another aspect, a term coupled or the like may refer to being indirectly coupled. 
     Terms such as top, bottom, front, rear, side, horizontal, vertical, and the like refer to an arbitrary frame of reference, rather than to the ordinary gravitational frame of reference. Thus, such a term may extend upwardly, downwardly, diagonally, or horizontally in a gravitational frame of reference. 
     The disclosure is provided to enable any person skilled in the art to practice the various aspects described herein. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring the concepts of the subject technology. The disclosure provides various examples of the subject technology, and the subject technology is not limited to these examples. Various modifications to these aspects will be readily apparent to those skilled in the art, and the principles described herein may be applied to other aspects. 
     All structural and functional equivalents to the elements of the various aspects described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. § 112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for”. 
     The title, background, brief description of the drawings, abstract, and drawings are hereby incorporated into the disclosure and are provided as illustrative examples of the disclosure, not as restrictive descriptions. It is submitted with the understanding that they will not be used to limit the scope or meaning of the claims. In addition, in the detailed description, it can be seen that the description provides illustrative examples and the various features are grouped together in various implementations for the purpose of streamlining the disclosure. The method of disclosure is not to be interpreted as reflecting an intention that the claimed subject matter requires more features than are expressly recited in each claim. Rather, as the claims reflect, inventive subject matter lies in less than all features of a single disclosed configuration or operation. The claims are hereby incorporated into the detailed description, with each claim standing on its own as a separately claimed subject matter. 
     The claims are not intended to be limited to the aspects described herein, but are to be accorded the full scope consistent with the language of the claims and to encompass all legal equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirements of the applicable patent law, nor should they be interpreted in such a way.