Abstract:
A strap for a wrist-wearable electronic device facilitates battery charging and the supply of electrical power to external devices. A housing for a battery is removably mounted to the center of a resin strap, and one or more batteries are lined up next to each other within the housing. The batteries and housing are curved to conform to the curvature of a user&#39;s wrist. A charging terminal for charging the batteries is provided and one or more output terminals for supplying electrical power to external devices are provided at four corners of the housing. The output voltages and diameters of the terminals are different and each terminal is provided with detachable resin covers. An overcharging prevention circuit is disposed between the charging terminal and an output terminal.

Description:
FIELD OF THE INVENTION 
     This invention relates to a structure for a strap for portable electronic equipment used with equipment such as electronic equipment that requires a secondary battery, to a charging method and arrangements for terminals for a structure for a strap for portable electronic equipment, and to a way of improving the comfort with which worn parts fit. 
     This invention further relates to a structure for a strap for portable electronic equipment in which cost effectiveness and mounting are improved by providing a second battery mounting and a strap separately, and implementing a structure for a strap for portable electronic equipment where gas generated by the secondary battery is discharged to outside. 
     DESCRIPTION OF THE RELATED ART 
     Conventionally, various methods have been proposed in order to extend power supply life for electronic devices and other portable electronic equipment. With, for example, technology disclosed in Japanese Patent Publication Laid-open No. Sho. 52-84435, a secondary battery is built-into a watch body, power supply life is extended by locating a thermo-element generator in a watch strap, and the number of times a battery is changed is reduced. Further, Japanese Patent Publication Laid-open No. Hei. 1-73916, discloses a secondary battery built into a watch strap, and a connection made with a watch body at an end piece. 
     Further, in recent years, large power supply capacities have become necessary as multi-functionality of electronic devices such as wristwatches has advanced. However, housing a battery on a battery strap-side has been proposed because large batteries cannot be built into a watch body because of the relationship of the case dimensions. With, for example, the technology disclosed in Japanese Utility Model Laid-open Publication No. Sho. 56-94982, a large capacity battery is housed in an end piece of a watch strap. 
     Still further, with technology disclosed in Japanese Utility Model Laid-open Publication No. Sho. 56-94982, housing a large capacity battery in the end piece of the watch strap restrains the extent to which the watch body can be made large. 
     However, with related electronic devices there is the problem that the size of the watch body becomes large due to storing a secondary battery in the watch body, and it has therefore been difficult to make the capacity of a secondary battery large. Charging from outside has also been problematic because the secondary battery is housed in the watch body. On the other hand, when a large capacity battery is housed in a watch strap, the supply of electrical power to equipment other than the watch cannot be achieved because the connection with the watch body is carried out at the end piece portion. In recent years, in addition to electronic devices portable electronic equipment such as portable telephones, pocket-sized games, and compact personal computers, etc. have become widespread and it would be useful to be able to provide electrical power to such equipment. 
     Next, the secondary battery becomes larger as larger power supply capacity is demanded so that even if this battery is housed in a watch strap, the watch will be difficult to fit on a persons wrist and will feel uncomfortable when worn. This is particularly conspicuous when used by a user with narrow wrists. In Utility Model Laid-open Publication No. Sho 58-88185, there is disclosed a paper battery housed in a watch strap but this is not employed as a secondary battery and furthermore, power supply capacity is insufficient for use as a secondary battery. It is therefore an object of this invention to provide a structure for a strap for portable electronic equipment where a large power supply capacity is maintained while providing a superior fit. 
     With the aforementioned related electronic devices consideration has not been given to changing a battery when a battery or secondary battery is housed in a watch strap. Further, when a large battery is housed in a watch strap, part of the watchstrap becomes large and the feeling when worn is not good. The object of the invention is to provide a structure for a strap for portable electronic equipment where battery changing is simple and which feels extremely comfortable when worn. 
     Further, secondary batteries of related electronic devices are housed in an airtight manner in order to prevent the infiltration of dust and sweat. However, minute amounts of gas are generated during charging by electrode agents used in secondary batteries such as lithium batteries, etc. Gas therefore accumulates at portions housing secondary batteries and the strap may therefore become deformed. It is therefore a further object of this invention to provide a structure for a strap for portable electronic equipment capable of effectively preventing deformation due to accumulation of gas. 
     SUMMARY OF THE INVENTION 
     In order to achieve the aforementioned object, in this invention, a secondary battery is housed in part of a strap and a charging terminal connected to this secondary battery is provided in the strap. By providing not only a charging terminal but also an output terminal, the supplying of electrical power to other electronic equipment is made possible. A dual-purpose input/output terminal can also be adopted as this charging terminal and output terminal. An overcharging prevention circuit is also provided in this invention in order to prevent overcharging while a charging operation is being performed from outside. 
     The range of compatible electronic equipment can also be broadened by changing over voltages outputted from the output terminal using a voltage changeover switch. It is also possible to provide a plurality of output terminals each outputting a different voltage, but it is preferable for the diameter of each terminal to be different in order to prevent erroneous connection to an output terminal of a different voltage. Further, as the charging terminal and output terminals are exposed, it is preferable to provide covers in order to prevent the infiltration of dust and sweat. In addition to typical electronic devices, this invention can also be applied to other portable electronic equipment that can be carried using a strap, such as, for example, Global Positioning Systems (GPS) and personal computers, and strap structures disclosed in the following embodiments can be employed in such cases. 
     In order to achieve the aforementioned objects, a plurality of secondary batteries are housed in part of a strap for carrying portable electronic equipment, the housing is curved, and the secondary batteries housed in the housing are curved. The whole strap is therefore curved as a result. In a further method, the housing is curved, and a curved secondary battery is housed within the housing. The entire strap can therefore be formed in a curved manner in this case in the same manner as described above. In addition to typical electronic devices, this invention can also be applied to other portable electronic equipment that can be carried using a strap, such as, for example, Global Positioning Systems (GPS) and personal computers. When the invention is employed with this equipment, the structure for the strap can be the same as disclosed for the following embodiments. 
     In order to achieve the aforementioned object, electrode wires are embedded in a strap and a plurality of slots that expose the surface of the electrode wires are provided. A battery housing provided separately from the strap is made detachable and electrode projections connecting with the battery are provided opposite the strap surface. The electrode projections make contact with the electrode wires so as to conduct while the battery housing is attached to the strap because the embedded electrode wires are exposed at the slots. As a plurality of slots are provided, the battery housing can be adjusted to a more comfortable position when worn. The strap and the battery housing are separate and are therefore changeable. 
     It is also possible to use electrode projections with pointed ends and not provide the slots. In this case, the battery housing can be adjusted to an appropriate position and the tips of the electrode projections then penetrate into the strap and conduct with the embedded electrode wires. The stage of adjusting the position of the battery housing can therefore be omitted with this configuration. In addition to typical electronic devices, this invention can also be applied to other portable electronic equipment that can be carried using a strap, such as, for example, Global Positioning Systems (GPS) and personal computers. 
     Further, in order to achieve the aforementioned object, in a structure for a strap for portable electronic equipment, a secondary battery is housed in part of a strap for carrying portable electronic equipment, and a gas release valve is provided in a secondary battery housing. Gas generated at the secondary battery is discharged to outside by opening the gas release valve and dust and sweat cannot infiltrate because the valve is closed. In addition to typical electronic devices, this invention can also be applied to other portable electronic equipment that can be carried using a strap, such as, for example, Global Positioning Systems (GPS) and personal computers. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1A-1C schematically show structures for an electronic equipment strap of a first embodiment of this invention; 
     FIG. 2 schematically shows a structure for an electronic equipment strap of a second embodiment of this invention; 
     FIGS. 3A-3B schematically show structures for an electronic equipment strap of a third embodiment of this invention; 
     FIGS. 4A-4B schematically show structures for an electronic equipment strap of a fourth embodiment of this invention; 
     FIGS. 5A-5B schematically show structures for an electronic equipment strap of a fifth embodiment of this invention; 
     FIGS. 6A-6B are plan view showing the structures of the electronic equipment strap shown in FIGS. 5; 
     FIGS. 7A-7C are three plane view showing outlines of the structure for the battery housing shown in FIGS. 5; 
     FIGS. 8A-8B are cross-sectional view showing an example structure for an electrode projection; 
     FIGS. 9A-9B are cross-sectional view showing structures for an electronic equipment strap of a seventh embodiment of this invention; 
     FIGS. 10A-10B are explanatory view showing the structure of the gas release valve shown in FIGS. 9; 
     FIGS. 11A-11B are cross-sectional view showing a further valve structure for an eighth embodiment of a structure for an electronic equipment strap; and 
     FIGS. 12A-12B are cross-sectional view showing a still further valve structure for a ninth embodiment of a structure for an electronic equipment strap. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following is a detailed description of the present invention with reference to the drawings, with this invention by no means being limited to these embodiments. 
     First Embodiment 
     FIGS. 1A-1C schematically show a structure for an electronic equipment strap of a first embodiment of this invention, with FIG. 1A being a plan view, FIG. 1B being a side view, and FIG. 1C being a further side view. An electronic equipment body is omitted from the drawings. This strap structure  100  has a housing  3  for housing secondary batteries  2  at the center of a resin strap  1 , and three secondary batteries  2  are lined up next to each other within the housing  3 . The secondary batteries  2  are, for example, lithium ion batteries, nickel hydrogen batteries, or nickel cadmium batteries, etc. A charging terminal  4  for charging the secondary batteries  2 , and three kinds of output terminal  5  to  7  for providing electric power to the outside are provided at the four corners of the housing  3  and are exposed to the outside of the strap  1 . Output voltages of each of the output terminals  5  to  7  are different, with, for example, the first output terminal  5  being 1.2V, the second output terminal  6  being 2.4V, and the third output terminal  7  being 3.6V. The diameters of each of the output terminals  5  to  7  are also different in order to prevent external equipment being mistakenly connected to the wrong voltage. More specifically, the diameters of the first to third output terminals  5  to  7  become smaller, in that order. 
     Detachable resin covers  8  are provided for the charging terminal  4  and the output terminals  5  to  7 . These covers  8  are connected by connectors  9  protruding from the vicinity of the container  3  in order to prevent the covers  8  from being lost. These covers  8  are formed integrally with the strap  1  and prevent dust and sweat from getting in through the terminal holes, as well as preventing short circuits with the outside. An overcharging prevention circuit  10  is also inserted between the charging terminal  4  and the first output terminal  5 , and is constructed from diodes and transistors, etc. Connection terminals of an external transformer can also be inserted into the charging terminal  4  during charging. 
     According to this strap structure  100  for an electronic equipment, the secondary batteries  2  can be easily and rapidly charged from outside. The capacity of the secondary batteries  2  can also be made large as it is not necessary to consider the size of the watch body because the secondary batteries  2  are provided in the strap  1 . It is also possible to provide electrical power to external portable electronic equipment because the output terminals  5  to  7  are provided. 
     Second Embodiment 
     FIG. 2 schematically shows a structure for an electronic equipment strap of a second embodiment of this invention. In a strap structure  200  of this second embodiment, three secondary batteries  2  are housed in the housing  3  of the strap  1 . The secondary batteries  2  are connected to a dual purpose input/output terminal  202  that functions as both a charging terminal and an output terminal. The input/output terminal  202  is sealed by a cover  8  formed integrally with the strap  1 , and a voltage changeover switch  203  is provided in the vicinity of the input/output terminal  202 . This voltage changeover switch  203  changes over the output voltage depending on the position which it is pushed into and is externally operated by the user. The voltage changeover switch  203  changes the output voltage by changing over the manner in which the three secondary batteries  2  are connected between series and parallel. Economies can therefore be made with regards to the number of parts and space by having a dual purpose terminal (the input/output terminal  202 ) that doubles as both a charging terminal and an output terminal. An overcharging prevention circuit can also be provided at the strap structure  200  and the terminal may be employed as a charging terminal and an output terminal rather than an input/output terminal. 
     Third Embodiment 
     FIGS. 3A-3B schematically show structure for an electronic equipment strap of a third embodiment of this invention, with FIG. 3A being a side view and FIG. 3B being a plan view. This strap structure  300  has a housing  3  for secondary batteries  2  at the center of a resin strap  1 , with three secondary batteries  2  being arranged in a curved manner within the housing  3 . The housing  3  is curved to an extent to fit onto the wrist of an average user. The secondary batteries  2  are, for example, lithium ion batteries, nickel hydrogen batteries, or nickel cadmium batteries, etc. 
     A charging terminal  4  for charging the secondary batteries  2 , and an output terminal  5  for providing electric power to outside are provided at the housing  3  and are exposed to the outside of the strap  1 . Conducting wire  26  for supplying electric power to a watch body  50  is provided within the strap  1 . One end of the strap  1  is inserted into the watch body  50  and conducts internally with a circuit substrate (not shown). Magic tape  28  is provided at the other end of the strap  1 , is passed through between the watch body  50  and a spring bar  27 , folded back, and fixed. According to this strap structure  300  for an electronic equipment, by giving the housing  3  a curved shape, the feeling of the fit on the wrist can be improved while maintaining a substantial power supply capacity. 
     Fourth Embodiment 
     FIGS. 4A-4B schematically show structure for an electronic equipment strap of a fourth embodiment of this invention, with FIG. 4A being a side view and FIG. 4B being a plan view. A characteristic of the strap structure  400  of a fourth embodiment is that a curved secondary battery is employed. Other aspects of the configuration are the same as for the third embodiment, and a description thereof is therefore omitted. Here, a polymer battery that can be molded with a high degree of freedom is employed as the secondary battery  2 . The feeling of the fit on the wrist can therefore also be improved with this structure while maintaining a substantial power supply capacity. 
     Fifth Embodiment 
     FIGS. 5A-5B are view showing a structure for an electronic equipment strap of a fifth embodiment of this invention, where FIG. 5A is a plan view and FIG. 5B is a side view. With this strap structure  500 , the resin strap  1  and the housing  3  for the secondary battery  2  are separate. The housing  3  has an overall curved shape with the secondary battery  2  being embedded within the housing  3 . The secondary batteries  2  are, for example, lithium ion batteries, nickel hydrogen batteries, or nickel cadmium batteries, etc. A charging terminal  4  for charging the secondary battery  2 , and an output terminal  5  for providing electric power to the outside are provided at the housing  3  and are exposed to the outside of the strap  1 . 
     FIG. 6A is a plan view of a strap showing the fifth embodiment of the present invention. Two electrode wires  11  are embedded in parallel within the strap  1 . The electrode wires  11  are wired in a rippled shape at the most curved portion of the strap  1 . A plurality of slots  12  are provided at the surface of the strap  1  and the electrode wires  11  are exposed to the outside via these slots  12 . On the other hand, electrode projections  31  exposed in the manner shown in FIG.  7  and coming into contact with the electrode wires  11  are provided at the housing  3 . A charging terminal  4  for charging the secondary battery  2 , and an output terminal  5  for providing electric power to the outside, are embedded at the housing  3 . The terminals  4  and  5  are wired so as to have the same polarity as that of the electrode wires  11  and are exposed to the outside of the strap. The electrode projections connect with the positive and negative poles of the secondary battery  2  within the housing  3  (not shown). A slot  32  that the strap passes through is also provided at the housing  3 . One end of the strap  1  then connects with the watch body so as to conduct with an internal circuit substrate (not shown). 
     When connecting the strap  1  and the housing  3 , the strap is first passed through the slot  32  and is positioned taking the positions of the slots  12  into consideration in a manner that ensures that the watch feels comfortable when worn. The electrode projections  31  of the housing  3  then fall into the slots  12  so as conduct with the electrode wires  11  (refer to FIG.  8 A). Any structure is acceptable for the electrode projections, providing that the terminals connected to the secondary battery  2  are urged towards the electrode wires  11 . For example, as shown in FIG. 8B, conduction can be achieved by sticking an electrode projection  35  with a pointed end into an electrode wire  11 . 
     If conduction is achieved between the electrode wires  11  and the electrode projections  31 , a rear cover  37  is fixed to the strap  1  using a mounting screw  36 . The method of fixing is by no means limited to a screwing method, and a clamping method may also be employed. In order to make the structure waterproof, a seal is formed around the slots  12  so as to provide sealing using fastening pressure when fixing the strap  1  using screws. When the capacity of the secondary batteries is small, charging is carried out using a separately prepared charger (omitted from the drawings), and the charger can then be connected to the charging terminal  4  during charging. 
     According to the above strap structure  500  for an electronic equipment, by making the housing  3  and the strap  1  separate, only the secondary battery can easily be changed. The feeling of the watch when worn can also be improved by adjusting the position of the housing  3  and it is also possible to change the strap  1 . 
     Sixth Embodiment 
     In the sixth embodiment, shown in FIG.  6 B and FIG. 8B, electrode projections  35  with pointed ends are employed but the slots  12  are not formed in the strap  1 . Conduction can then be achieved by the pointed ends of the electrode projections  35  penetrating directly into the strap  1 . According to this structure, as shown in FIG.  6 B and FIG. 8B, the stage of adjusting the position of the housing  3  is no longer carried out and manufacture is straightforward because the slots  12  are not formed. The above configuration is by no means limited to secondary batteries, and can also be used for primary batteries. Further, the embedded wires do not break even when the strap is bent because the wiring embedded within the strap is wired in a partially rippled manner. 
     Seventh Embodiment 
     FIGS. 9A-9B are view showing a structure for an electronic equipment strap of a seventh embodiment of this invention, where FIG. 9A is a plan view and FIG. 9B is a side view. An electronic equipment body is omitted from the drawings. This strap structure  600  has a housing  3  for housing secondary batteries  2  at the center of the resin strap  1 . The secondary batteries  2  are, for example, lithium ion batteries, nickel hydrogen batteries, or nickel cadmium batteries, etc. The charging terminal  4  for charging the secondary battery  2  is provided at the housing  3 . The output terminal  5  for supplying electrical power to external portable electronic equipment is provided on the opposite side to the charging terminal  4 . A gas release valve  6  for releasing gas that accumulates within the housing  3  is provided at a side of the housing  3 . 
     FIGS. 10A-10B are cross-sectional view of a structure for the gas release valve shown in FIGS.  9 . As shown in FIG. 10A, this valve  46  comprises a gas introduction section  61  and a valve chamber  60  formed in the housing  3  made of a soft resin such as polyurethane, and a hard ball  62  and spring  63  for closing the gas introduction section  61 . The hard ball  62  housed within the valve chamber  60  is usually repelled by the spring  63  so as to close the gas introduction section  61  and prevent the infiltration of sweat and water, as shown in FIG.  10 A. When gas builds up in the housing  3  so that the pressure becomes high, the hard ball  62  is moved by this high pressure, as shown in FIG. 10B, and gas is released from the valve chamber  60  to the outside via an outlet  66 . The spring  63  is adjusted so as to flex under a prescribed gas pressure. 
     Eighth Embodiment 
     FIGS. 11A-11B are cross-sectional view of an eighth embodiment showing a further valve structure. This structure is substantially the same as the structure of FIG. 10, and comprises a gas introduction section  61  and a valve chamber  60  formed in the housing  3  made of a soft resin such as polyurethane, and a hard ball  62  for closing the gas introduction section  61 . However, a spring  64  is integrally made of part of the housing  3 , in place of the spring  63 . The hard ball  62  housed within the valve chamber  60  is usually repelled by the spring  64  so as to close the gas introduction section  61  and prevent the infiltration of sweat and water, as shown in FIG.  11 A. When gas builds up in the housing  3  so that the pressure becomes high, the hard ball  62  is moved by this high pressure, as shown in FIG. 11B, and gas is released from the valve chamber  60  to the outside via the outlet  66 . The spring  64  is adjusted so as to flex under a prescribed gas pressure, and a notch for releasing gas is provided at at least one location at the spring  64 . 
     FIGS. 12A-12B are cross-sectional view of an ninth embodiment showing a further simplified valve structure. It is also possible to have a configuration that utilizes the housing  3  being made of a soft resin such as polyurethane where an elastic valve  65  has a gas introduction section  61  in a wedge-shape facing outwards. In this case, when the outer pressure and inner pressure is the same, the elastic valve  65  is closed due to the elasticity of the rubber. When gas is generated so that the inner pressure becomes high, tips of the valve  65  open up and gas is discharged to outside. The valve structure is by no means limited to that shown in FIGS. 10 to FIG. 12, and simplified structures are preferred. For example, a gate valve, cock, or diaphragm valve etc. can be employed rather than a check valve, with gas then being released manually. 
     As described above, according to the structure for a strap for portable electronic equipment of this invention, the following effects can be obtained. 
     Firstly, charging can be carried out from outside both easily and rapidly. Secondly, electrical power can be provided to other portable electronic equipment. Thirdly, economies can be made with regards to the number of parts and to space by employing an input/output terminal. Fourthly, overcharging of a secondary battery can be prevented by an overcharging prevention circuit. Fifthly, compatibility can be attained with portable electronic equipment of different voltages by changing the voltage using a voltage changeover switch. Sixthly, erroneous operation can be prevented by having the diameter of the terminals for the plurality of output terminals provided different diameters. Seventhly, infiltration of dust and sweat and short circuiting with the outside can be prevented by providing covers for the terminals. 
     According to the structure for a strap for portable electronic equipment of this invention, equipment can be made to fit in an extremely comfortable manner while maintaining a large power supply capacity because the strap as a whole can be made curved. 
     According to the structure for a strap for portable electronic equipment of this invention, a superior fit can be provided because a battery housing can be fixed at an arbitrary position. Further economies are also provided for because the strap is changeable. Battery changing can also be further simplified by providing the battery housing and the strap separately. 
     According to the structure for a strap for portable electronic equipment of this invention, a secondary battery is housed in part of a strap for carrying portable electronic equipment, and a gas release valve is provided in the portion housing this secondary battery. Deformation of the strap due to gas accumulating at the portion housing the secondary battery can therefore be prevented.