Abstract:
An arrangement includes a first connector coupled to a first device and a second connector coupled to a second device. A cable connects the first and second connectors. At least a portion of the cable forms a substantially oval-shaped coil. At least one of the first and second devices is a user-wearable device.

Description:
FIELD OF THE INVENTION 
   The present invention generally relates to mobile devices. 
   BACKGROUND INFORMATION 
   A wearable device, such as a ring scanner, generally comprises a scanning unit coupled to a computing unit. The scanning unit acquires data and transmits the data to the computing unit via a coupling arrangement. One conventional coupling arrangement is a wired cord that is generally helical-shaped (e.g., a circular spiral). The cord comprises one or more wires covered in an insulating material, such as plastic or rubber. An advantage of forming the cord as a helix is that a length of the cord is reduced by winding the cord into compact coils. If the reduced length is insufficient to meet a user&#39;s needs, the cord can be stretched to its full length. The cord generally has elastic properties enabling it to return to a relaxed state when not acted upon by pulling forces. 
     FIG. 1  shows a perspective view of a mobile device  100 . The device  100  includes a scanning arrangement  110  coupled to a triggering arrangement  120  and a cord  134 . The scanning arrangement  110  may be a bar code scanner, an infrared sensor, an RFID reader, etc. The triggering arrangement  120  may include a trigger button  122  and a strap  124 . As shown in  FIG. 1 , the cord  130  may include a helical section  134 . A proximal end of the cord (not shown) is coupled to a computing unit worn by the user. For example, the computing unit can be worn on a wrist or a forearm, while the device  100  is worn on a finger. 
   Despite its advantages, a helical cord may be a potential source of inconvenience to the user. For example, if the computing unit is worn on the forearm, the cord  130  may be stretched to a length that makes the cord  130  uncomfortable. The stretching causes the cord  130  to be in a constant state of tension, limiting or making difficult movement of the device  100 . As a result, the user may be required to exert a large amount of effort to position or maneuver the device  100 . Over an extended period of use, this may result in user fatigue. In addition, friction from the cord  130  may cause further discomfort to the user. Another disadvantage is that if the computing unit is worn closer to the device  100  (e.g., at the wrist), the cord  130  can bow outward, obstructing the user&#39;s view of the computing unit and potentially getting tangled with itself or with another object. The force and length of cord required is also controlled by the diameter of the helix. If a low force, long cord is required in a short distance, it may be necessary to create a large diameter helix. The large diameter then presents itself as a hook point which could cause the user inconvenience. 
   SUMMARY OF THE INVENTION 
   The present invention relates to a first wearable device which includes a first connector; a second wearable device including a second connector; and a coupling arrangement coupling the first and second devices. The coupling arrangement includes a third connector coupled to the first connector, a fourth connector coupled to the second connector and at least one substantially oval-shaped coil connects the third and fourth connectors. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a mobile device with a conventional cord; 
       FIG. 2  is a top view of an exemplary embodiment of a mobile device according to the present invention; 
       FIG. 3  is a perspective view of a portion of the device of  FIG. 2 ; 
       FIG. 4  is a top view of the device of  FIG. 2  in a first wearing position; 
       FIG. 5  is a top view of the device of  FIG. 2  in a second wearing position; and 
       FIG. 6  shows an exemplary embodiment of another mobile device according to the present invention. 
   

   DETAILED DESCRIPTION 
   The present invention may be further understood with reference to the following description and the appended drawings, wherein like elements are provided with the same reference numerals. The present invention generally relates to mobile devices. For example, the mobile devices may be data acquisition devices, data processing devices, data transmission devices, audio/video devices, etc. An exemplary embodiment of the present invention is described with reference to a ring scanner, however those skilled in the art will understand that the present invention may be implemented with any type of mobile device that utilizes a corded coupling arrangement, (e.g., a wrist-mounted scanner, a glove scanner, an media (e.g., mp3, video, compact disc, etc.) player, a global positioning system, a walkie-talkie, a mobile computer, etc.). 
     FIG. 2  shows a top view of an exemplary embodiment of a data acquisition device (e.g., a ring scanner)  200  according to the present invention. The device  200  may include one or more data acquisition arrangements (e.g., a imager, a barcode scanner, an RFID reader, an keyboard, a touchpad, etc.) disposed within a housing  210 . The device  200  may also include a trigger  220  coupled to the housing  210  for engaging the one or more data acquisition arrangements. The trigger  220  may be a pushbutton, a slide switch, a rocker switch, or any other mechanical and/or electrical triggering mechanism known to those skilled in the art. The housing  210  may be worn on at least one finger using an elastic strap, a band, or other conventional attachment arrangement. When worn, the housing  210  may be substantially parallel to an anterior surface of the finger, with the trigger  220  positioned along a medial side of the finger (e.g., proximal to an opposing thumb). 
   The device  200  may communicate with a computing device, such as a portable computer, a desktop computer, a PDA, a proprietary receiving unit, a mobile phone, a media player, etc. (not shown). The computing device may transmit or receive data and instructions to/from the device  200 . For example, the computing device may receive data corresponding to an object scanned by the device  200 . The computing device may also transmit instructions to the device  200  in order to specify a particular data format for receiving the data. 
   If the computing device is the portable computer or the desktop computer, it may not be worn by the user. For example, the computing device may be located on a desk or attached to a wall. If the computing device is the PDA or the proprietary unit, it may be worn on a body part (e.g., an upper arm, a forearm, a leg, etc.) of the user. Regardless of where the computing device is located, it is physically coupled to the device  200  via a wired cord  230 , which provides a medium through which data and/or instruction signals are communicated between the computing device and the device  200 . The medium may, for example, include one or more copper wires surrounded by an insulating material (e.g., rubber coating). The insulating material has an elastic property allowing the cord  230  to be stretched and bent while retaining the ability to return to an original shape. Although the elastic property may allow the cord  230  to return to the original shape when no longer stretched, it may be desirable to limit this elastic response in order to make wearing the device  200  more comfortable for the user. For example, if the elastic response is too strong, the user may experience fatigue when trying to maintain the cord  230  in a stretched position for an extended period of time. If the elastic response is too weak, the cord  230  may become permanently deformed over time as a result of repeated and/or excessive stretching. The insulating material may also be selected based on its dielectric properties in addition to other physical properties, such as smoothness (e.g., frictional coefficient), hardness, permeability, etc. 
   A connecting arrangement  238  is disposed on a proximal end of the cord  230 . The connecting arrangement  238  may comprise a hardware connector for coupling to a receiving arrangement of the computing device. For example, in one embodiment, the connecting arrangement  238  may be a proprietary arrangement. In other embodiments, the connecting arrangement  238  may be a standardized arrangement (e.g., USB, parallel port, serial port, etc.). In one embodiment, the connecting arrangement  238  is detachably coupled to the receiving arrangement. However, in other embodiments, the connecting arrangement may be integral with the receiving arrangement of the computing device. 
   In an exemplary embodiment, the cord  230  may include a tapered distal section  232 , a coiled proximal section  234 , and a straight middle section  236 . The tapered section  232  is located at a point where the cord  230  is coupled to the device  200  and may taper proximally towards the coiled section  234 . The tapered section  232  is also substantially thicker than a remainder of the cord  230  and may include one or more grooves disposed around an outer surface thereof. The grooves allow the housing  210  to pivot and flex, while the thickness of the tapered section  232  protects the cord  230  from damage and provides mechanical stability for the coupling point. A length of the tapered section  232  may be predetermined according to desired flexibility characteristics specified by a manufacturer of the device  200 . Generally, the tapered section  232  is less flexible than the remainder of the cord  230 . Accordingly, if a greater amount of flexibility is desired, the length of the tapered section  232  may be minimized. Similarly, if less flexibility is desired, the length of the tapered section  232  may be increased. The thickness of the tapered section  232  may also be predetermined in addition, or in alternative, to adjusting the length. For example, an increase in thickness may result in a corresponding decrease in flexibility. 
   In one embodiment, the tapered section  232  may be integral with the housing  210 . For example, the tapered section  232  may be integrally formed with or permanently bonded, melded, etc. to the housing  210 . In other embodiments, the tapered section  232  may be detachably coupled to the housing  210 . Thus, the tapered section  232  may function as a removable plug, allowing the cord  230  and/or the computing device to be stored separately from the housing  210 . 
   The coiled section  234  includes a series of substantially oval-shaped coils. As best seen in  FIG. 3 , each coil comprises an opposing pair of semi-circular members  255  and a pair of opposing elongated members  257  that are substantially parallel to each other and joined at corresponding ends by a semi-circular member  255 . The semi-circular members  255  and the elongated members  257  may be integrally formed using a shaping procedure, such as molding, extrusion, heat curing, etc. For example, the coiled section  234  may be molded integrally with the straight section  236  and wrapped into ovals prior to hardening/curing. 
   In an exemplary manufacturing process, a portion of a raw cord is wrapped around a mandrel into an oval shape. The cord may be wrapped around the mandrel in a direction opposite to that desired. The cord/mandrel assembly is then placed into an oven and heated up to soften the cord. Once the cord is sufficiently cooled, it is removed from the mandrel and has an oval shape. The cord is then turned-over on itself, which adds tension and springiness. Once flipped over on itself, the coil is oriented in the desired direction. 
   A length of the straight section  236  may be predetermined based on the manufacturer&#39;s specifications. For example, it may be specified that, when the computing device is worn at the wrist, the straight section  236  should not extend proximally past the wrist. Accordingly, in an exemplary embodiment, a combined length of the straight section  236  and the tapered section  232  may be approximately 1.6″. 
   The dimensions of the semi-circular and elongated members  255 ,  257  may also be selected according to the manufacturer&#39;s specifications. Several dimensions, such as length, thickness and cross-sectional area, may be adjusted in accordance with desired performance characteristics. For example, increasing a height of each coil may result in an increase in cross-sectional area of each coil, since a radius of the semi-circular members  255  is enlarged. However, this may result in unnecessary bulk, making the cord  230  unwieldy. Furthermore, it may not be space-efficient since the empty space surrounded by the coil is increased. Accordingly, if the manufacturer desires to increase the length of the cord  230  without increasing the height, a length of the elongated members  255  may be increased instead. However, if the elongated members  255  are too long, the coils may become uncomfortably heavy or extend too much beyond the user&#39;s body (e.g., a side of the forearm). In an exemplary embodiment where the cord  230  is draped along the wrist, the radius of the semi-circular members  255  may be approximately 0.3″ and the length of the elongated members  257  may be 0.6″, making an overall length of each coil 1.6″. In addition, the thickness may be such that a distance between outer edges of the elongate members  255  is approximately 0.586″. 
   Another characteristic that may affect the length of the cord  230  is the number of coils in the coiled section  234 . The length of the cord  230  may be increased by adding more coils to a design thereof. However, additional coils may have undesirable effects such as an increased bulk and an increased likelihood of kinking and tangling. 
   As discussed above, the dimensions of the cord  230  may be adjusted depending on where the device  200  is worn on the body. In an exemplary embodiment, the length of the cord  230  may be predetermined such that the length is appropriate for multiple body locations. For example, the cord  230  may be dimensioned so that the cord  230  is in a relaxed (e.g., coiled) stated when the computing device is worn at a first body location (e.g., the wrist) and in a stretched (e.g., straight) state when the computing device is worn at a second location (e.g., the wrist). 
     FIG. 4  shows an exemplary embodiment of the device  200  when the cord  230  is in the relaxed state. As shown, the device  200  is worn over an index finger  44  and coupled to a computing device  300 , which is worn on a wrist  42 . The cord  230  rests on an anterior surface of the wrist  42 , distal of the computing device  300 . In one embodiment, the cord may be approximately 2.9″ in the relaxed state. It will be understood that other positions may also produce the relaxed state. That is, there may be a range of relative positions (e.g., a first position range) for the device  200  and the computing device  300 , in which the cord  230  is in the relaxed state. Depending on a relative position within the first position range, the coils of the cord  230  may be substantially resting together (as shown in  FIG. 4 ) or spaced slightly apart. 
     FIG. 5  shows an exemplary embodiment of the device  200  when the cord  230  is in the stretched state. As shown, the device  200  is worn over the index finger  44  and coupled to the computing device  300 , which is worn on a forearm  52 . The cord rests on an anterior surface of the forearm, and may, in one embodiment, by approximately 10.5″ when fully stretched (e.g., taut). However, the cord  230  may not necessarily be taut in the stretched state. For example, the relative position of the device  200  and the computing device  300  as shown in  FIG. 5  may correspond to one of several positions (e.g., a second position range) in which the cord  230  is in the stretched state. Depending on a relative position within the second position range, the coils of the cord  230  may be substantially spaced apart, or the coils may be substantially nonexistent (e.g., a substantial portion of the coiled section  234  becomes linear as a result of stretching). 
   In designing the cord  230 , the manufacturer may optimize characteristics such as the length, for use in a range of positions (e.g., the first position range) while still allowing for comfortable usage when the housing  210  and the computing device are placed further apart (e.g., the second position range) or closer together (e.g., a third position range). For example, the length may be chosen so that the cord  230  has little or no slack in the first position range, is not taut in the second position range, and does not exhibit significant bowing in the third position range. 
   When the device  200  is worn, the cord  230  may be draped over at least a portion of the anterior surface of the wrist. If the computing device is worn on the forearm, the cord  230  may be draped further along the arm. It will be appreciated by those of skill in the art that, because of the oval shape of the coils, the cord  230  requires fewer coils than a conventional data acquisition device using a helical cord. In order to achieve a given length, fewer coils are required because each coil in the present invention has a substantially larger circumference than that of the helical coil. Thus, the cord  230  may be less likely to kink or tangle. 
   When draped across the wrist in the relaxed state, at least one of the elongated members  257  are resting against the surface of the wrist. Because the length is sized appropriately (e.g., there is little or no slack), and because the elongated members  257  do not curve away from the surface of the wrist (unlike the helical cord), the cord  230  resists lateral movement such as outward bowing and slippage. Thus, the user&#39;s view of the computing device is not obstructed. 
   In addition, the cord  230  can also comfortably accommodate placement of the computing device at the forearm. When draped across the forearm in the stretched state, the coiled section  234  is placed in a state of tension. However, tension in the cord  230  is decreased compared to the helical cord because the elongated members  257  remain in a substantially relaxed state. The semi-circular members  255  perform a majority of the stretching by deforming under tensile stress so that the tension is concentrated at the semi-circular members  255  rather than at the elongated members  257 , which may not need to stretch. In contrast, the helical coil distributes tension across the entire body of the coil. As a result, the helical coil may require more force in order to stretch. Thus, the cord  230  is less tiring when used over an extended period of time and allows the user to remain relaxed. Furthermore, because the cord  230  is not stretched taut, less contact is made with the user&#39;s skin, which reduces a likelihood of frictional discomfort. 
   As stated above, the present invention may be implemented in any mobile device that utilizes a cord. For example,  FIG. 6  shows an exemplary embodiment of an earpiece  600 , which is adapted to be worn on an outer ear  63 . The earpiece  600  may be coupled via a cord  630  to an audio device, such as a headset  64 . The headset  64  may, like the computing device  300  of  FIGS. 3 and 4 , be worn at a number of different locations. For example, the headset  64  may be worn in conjunction with an armband, a belt holster, placed in a pocket, held in a hand, etc. Thus, the earpiece  600  and the device  300  may also have a plurality of relative positions in which the cord  630  may be in a relaxed or stretched state. 
   The present invention has been described with reference to the above exemplary embodiments. One skilled in the art would understand that the present invention may also be successfully implemented if modified. Accordingly, various modifications and changes may be made to the embodiments without departing from the broadest spirit and scope of the present invention as set forth in the claims that follow. The specification and drawings, accordingly, should be regarded in an illustrative rather than restrictive sense.