Patent Publication Number: US-2005130682-A1

Title: Cordless device system

Description:
TECHNICAL FIELD  
      The present invention relates to a cordless instrumental system, in which a cordless instrument detachable from a charger is attached to said charger an charged therefrom, such as portable electrical instruments, personal computers, cell phones, and portable informational instruments such as PDA.  
     BACKGROUND ART  
      Among the cordless instruments, such have so far been rapidly increasing as are made cordless with built-in batteries. As built-in batteries, disposable primary batteries like dry cells and repeatedly usable secondary batteries are mainly used. However, primary batteries require laborious procedure to exchange upon potential extinction, and time for purchasing new ones. Disposition of consumed cells is also a problem. For this reason, costs for cells and maintenance are needed for such instruments as electric torches for business.  
      As for secondary batteries, in case that electricity was discharged when it is to be used, it has to be charged long with relatively low current for the characteristics of secondary batteries of utilizing chemical reactions, therefore it can not be used while being charged. Secondary batteries can be repeatedly charged and discharged which is not possible for primary batteries, but it has its own limit, and exchange is necessary upon life extinction. In such a case, same problems as with the above-mentioned primary batteries are encountered.  
      Therefore, it is under consideration to utilize an electric double-layer capacitor in place of a secondary batteries by making use of the merit of high current charging and discharging of said electric double-layer capacitor. An electric double-layer capacitor has the structure to store the positive and the negative charges parallelly in the electric double layer generated upon the contact of an electrode and electrolyte. Since it is not accompanied by chemical reaction like batteries, rapid charge and discharge are possible. However, an electric double-layer capacitor has the smaller capacity per volume than that of secondary batteries, therefore it is severely restricted on operating time and the purpose of use.  
      The conventional construction of the instruments using an electric double-layer capacitor is such as to charge the instrument having an electric double-layer capacitor with, for example, an electric charger. Said electric charger is operated with alternate current source. Now, as instruments having the electric source with an electric double-layer capacitor, prototype electric cars are manufactured in which an electric double-layer capacitor with large volume can be mounted with the same capacity as the conventional secondary batteries. Also an electric double-layer capacitor of small capacity is used as the backup source for semiconductor memory devices for computers, in case that the capacity of a secondary battery is too large.  
      Further there is an electric charger using a direct current source rectified from commercial power source for cordless instruments using electric double-layer capacitors, as disclosed in, for example, Japanese publication JP H08-31339 B (p. 2-5, FIG. 1-3). However, since conventional cordless instruments have an electric double-layer capacitor as a sole electric source, they have a problem that their volume is larger than the secondary batteries of equal capacity for long operation time.  
      Thus, there is a problem that a conventional secondary battery can not be replaced with an electric double-layer capacitor having the smaller capacity per volume than said secondary batteries for small cordless instruments and the like.  
      Taking into consideration the above-mentioned aspects, the present invention has the object to provide a cordless instrumental system capable of rapid charging effectively and efficiently.  
     DISCLOSURE OF THE INVENTION  
      In order to achieve the above-mentioned object, the first aspect of the present invention is a cordless instrumental system, in which a cordless instrument detachable from a charger is attached to said charger and charged, comprising: a first storage part chargeable from a direct current source included in said charger; a first charge and discharge control circuit to control the charge and discharge of said first storage part, a second storage part included in said cordless instrument; and a second charge and discharge control circuit to control the charge and discharge of said second storage part; and is capable of charging at least from said first storage part to said second storage part upon attaching said cordless instrument.  
      Said first and second storage parts are preferably constructed with an electric double-layer capacitor or an electrochemical capacitor. Also said second storage part is preferably capable of charging from said first storage part or said direct current source.  
      It is preferable to constitute the charging circuit for said second storage part so as to be switched to said first storage part or said direct current source. Also, said second charge and discharge control circuit is preferably included in said cordless instrument or said charger. Further, said first storage part is preferably connected parallelly in plurality to said direct current source.  
      According to said first aspect of the present invention, the first storage part is charged in advance from the direct current source built in a charger, and, upon connecting the cordless instrument, the storage part of the cordless instrument is first charged from the storage part of the charger. Then, in case that the voltage has not reached the rated value, the circuit is switched to the supply from the direct current source, charge is continued from the direct current source till the rated voltage is reached, and then charging is finished. Since the storage part of the cordless instrument of the present invention is preferably provided with an electrochemical capacitor, rapid charging is possible, as well as it is applicable to various cordless instruments, since its volume is smaller than the conventional electric double-layer capacitor.  
      The charge and discharge control circuit of the second storage part can be allocated not at the charger side but at the cordless instrument side. If the storage part of a charger of the present invention is constituted with an electric double-layer capacitor or an electrochemical capacitor, then rapid charge of the storage part of a charger is also possible. Also, the second storage part of a charger is, by being connected parallelly in plurality to a direct current source, capable of switched use, and of immediate full charging by switching in turn when the cordless instrument is connected. Thus, the cordless instrumental system always capable of rapid charging can be realized.  
      In order to achieve the above-mentioned object, the second aspect of the present invention is a cordless instrumental system, in which a cordless instrument detachable from a charger is attached to said charger and charged, characterized to comprise: a first storage part chargeable from a direct current source included in said charger; a third storage part chargeable from the direct current source, and chargeable to said first storage part; a first charge and discharge control circuit to control charge and discharge of said first and third storage parts; a second storage part included in said cordless instrument; and a second charge and discharge control circuit to control charge and discharge of said second storage part; and is capable of charging at least from said first storage part to said second storage part upon attaching said cordless instrument.  
      In said cordless instrumental system of the second aspect, said first and second storage parts are preferably constituted with an electric double-layer capacitor or an electrochemical capacitor. Said third storage part is preferably constituted with a battery capable of charge and discharge. The third storage part can be charged from said direct current source. Said second storage part is preferably capable of charging from said first storage part or said direct current source.  
      In said cordless instrumental system of the second aspect, depending upon the charge output of said first storage part, the charge route to said second storage part can be switched to the first storage part or said direct current source. Said second charge and discharge control circuit is preferably included in said cordless instrument or said charger. Further, said first storage part is preferably connected parallelly in plurality to said direct current source.  
      According to said second aspect of the present invention, the first and the third storage parts are charged in advance from the direct current source built in a charger, and, upon connecting the cordless instrument, the storage part of the cordless instrument is first charged from the first storage part of the charger. At this point, the first storage part is charged from the third storage part so as to immediately compensate from the third storage part the electricity discharged from the first storage part. As a result, no voltage lowering occurs in the first storage part, the voltages between the first and the second storage parts do not approach equal, and a certain potential difference is maintained. Consequently, rapid charge from the first to the second storage parts is made possible.  
      Here, in case that the voltage has not reached the rated value in the second storage part at this point, the circuit can be switched to the supply from the direct current source, charge is continued from the direct current source till the rated voltage is reached, and then charging is finished. According to the present invention, no voltage lowering occurs in the first storage part, the voltages between the first and the second storage parts do not approach equal, thereby a certain potential difference is maintained, and thus it is effectively applicable to various cordless instruments by rapid charge from the first to the second storage parts.  
      The charge and discharge control circuit of the second storage part can be allocated not at the charger side but at the cordless instrument side. If the first storage part of a charger of the present invention is constituted with an electric double-layer capacitor or an electrochemical capacitor, then rapid charge of the storage part of a charger is also possible. The first storage part of a charger is, by being connected parallelly in plurality to a direct current source, capable of supplying large current, and of immediate full charge. Also, the switched use is possible, and thereby the immediate full charging is also possible by switching in turn, when the cordless instrument is connected. Thus, the cordless instrumental system always capable of rapid charging can be realized. Also, the third storage part has the function to immediately supply electricity when the first storage part is discharged. Accordingly, the first storage part can always maintain the required voltage, and the charge speed can be always maintained above a certain value.  
      In order to achieve the above-mentioned object, the third aspect of the present invention is a cordless instrumental system, in which a cordless instrument detachable from a charger is attached to said charger and charged, characterized to comprise: a first and the third storage parts chargeable from said direct current source, and provided in said charger; a second and the fourth storage parts included in said cordless instrument; a charge and discharge control circuit to control charge and discharge of said first to fourth storage parts; and a discharge control circuit to control discharge of said second and fourth storage parts; and is capable of charging at least from said first and third storage parts to said second storage part, as well as of charging from said third storage part to said fourth storage part, upon attaching said cordless instrument.  
      According to said third aspect of the present invention, the first and the third storage parts are charged in advance from the direct current source built in a charger. Upon connecting the cordless instrument, the second storage part of the cordless instrument is first charged from the combined source of the first and the third storage parts connected in series in a charger. When the second storage part is rapidly charged to full capacity, charging of the fourth storage part follows. The second storage part is that capable of rapid charge, and the fourth storage part is a conventional chargeable and dischargeable battery, and charged at the conventional speed. Therefore, taking into consideration the case where the charging time has some additional allowance, the fourth battery may be charged from the third battery so far as the time allows after the rapid charging to the second storage part is completed.  
      Here, by constituting the first storage part of a charger with an electric double-layer capacitor or an electrochemical capacitor, it is also possible to rapidly charge the storage part of a charger. Also, the second storage part of a cordless instrument is capable of rapid charge by adopting an electric double-layer capacitor or an electrochemical capacitor. Further, since the fourth storage part is provided to a cordless instrument, the second storage part need not begin to be used immediately after the completion of rapid charge, therefore if there is additional allowance of time, the object of charge may be switched to the fourth storage part, and may be charged so far as the time allows. Thus, the cordless instrumental system, capable of rapid charging and long life, and the repeated charge and discharge, can be realized. 
    
    
     BRIEF DESCRIPTION OF FIGURES  
      The present invention will better be understood from the following detailed description and the drawings attached hereto showing certain illustrative forms of embodiment of the present invention. In this connection, it should be noted that such forms of embodiment illustrated in the accompanying drawings hereof are intended in no way to limit the present invention but to facilitate an explanation and an understanding thereof in which drawings:  
       FIG. 1  is a diagonal view illustrating a concrete structural example of the cordless instrumental system in accordance with an embodiment of the present invention;  
       FIG. 2  is an internal structural view of a charger in accordance with the first embodiment of the present invention;  
       FIG. 3  is a view illustrating an internal structure of an inductor as a cordless instrument in accordance with the first embodiment of the present invention;  
       FIG. 4  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the first embodiment of the present invention;  
       FIG. 5  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the second embodiment of the present invention;  
       FIG. 6  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the third embodiment of the present invention;  
       FIG. 7  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the fourth embodiment of the present invention;  
       FIG. 8  is a block diagram illustrating a modified example of a cordless instrumental system in accordance with the present invention;  
       FIG. 9  is an internal structural view of a charger in accordance with the fifth embodiment of the present invention;  
       FIG. 10  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the fifth embodiment of the present invention;  
       FIG. 11  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the sixth embodiment of the present invention;  
       FIG. 12  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the seventh embodiment of the present invention;  
       FIG. 13  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the eighth embodiment of the present invention;  
       FIG. 14  is a block diagram illustrating a modified example of a cordless instrumental system in accordance with the present invention;  
       FIG. 15  is an external diagonal view illustrating a concrete structural example of a cordless instrumental system in accordance with the ninth embodiment of the present invention;  
       FIG. 16  is an explanatory view of the internal outline of a charger of  FIG. 15 ;  
       FIG. 17  is a structural view of the internal outline of an induction rod of  FIG. 15 ;  
       FIG. 18  is a block diagram illustrating a structural example of a cordless instrumental system in accordance with the ninth embodiment of the present invention;  
       FIG. 19  is a flowchart illustrating the processing of a charge and discharge control circuit controlling the charge of the first and the third storage parts of a cordless instrumental system in accordance with the ninth embodiment of the present invention; and  
       FIG. 20  is a flowchart illustrating the processing of a charge and discharge control circuit controlling the charge of the second and the fourth storage parts of a cordless instrumental system in accordance with the ninth embodiment of the present invention.  
    
    
     BEST MODES FOR CARRYING OUT THE INVENTION  
      Hereinafter, certain forms of embodiment of the present invention will be described in detail with reference to the drawing figures.  
       FIG. 1  illustrates a concrete structural example of the cordless instrumental system in accordance with the first embodiment of the present invention. The cordless instrument in said embodiment is so constituted as to have an induction rod  20  detachable from a charger  10 , and to be charged with said induction rod being attached to the charger  10 .  
       FIG. 2  illustrates a structural example of a charger  10 . The charger  10  comprises a direct current source  11  to generate direct current by being supplied with electricity from a domestic power source or the like, a storage part (a first storage part)  12  chargeable from said direct current source  11 , and a charge and discharge control circuit (a first charge and discharge control circuit)  13  to control charge and discharge of said storage part  12 . Said components are allocated in a box  14 , and the direct current source  11  is supplied with electricity from a terminal  15 . At the top of the box  14  is provided a charge terminal  16  connected to the induction rod  20 .  
       FIG. 3  illustrates a structural example of an induction rod  20 . The induction rod  20  is shaped as a stick, and includes a storage part (a second storage part)  21  and a charge and discharge control circuit (a second charge and discharge control circuit)  22  to control charge and discharge of said storage part  21 . Inside a luminous part  23  are provided a plurality of light sources (LED, for example)  25  by a retainer  24 . LED  25  is switched on and off with operation of a switch  26 . Beneath the induction rod  20  is provided a charge terminal  27  connected to the charger  10 .  
       FIG. 4  illustrates a structure of a cordless instrumental system including a charger  10  and an induction rod  20 . The storage part  21  of said induction rod  20  is constituted with an electrochemical capacitor. The electrochemical capacitor used here is also called a pseudo-capacity capacitor, and is that utilizing the pseudo-capacity by redox reaction with the oxides RuO 2  and IrO 2  of the platinoid elements Ru (rutenium) and Ir (iridium) as electrodes. The capacity twice as large or even more than that per unit volume of an electric double-layer capacitor has already been realized in practical use. The chargeability and dischargeability of large current are equal to those of an electric double-layer capacitor.  
      As the electrochemical capacitor in the storage part  21 , two of the voltage 2.3V-120 F were connected in parallel in this example. The direct current source  11  of the charger  10  is 12V,  5 A, and the electric double-layer capacitor of the storage part  12  is five of 2.3V-60 F connected in series as a unit, and further 4 of these units connected in parallel and is 11.5V-48 F (hereinafter, such series-parallel connection is simply called 5 series/4 parallel).  
      The first charge and discharge control circuit  13  and the second charge and discharge control circuit  22  control the voltage not to exceed the preset voltage (rated voltage) (overvoltage control function) upon charging the storage parts  12  or  21 , respectively, and also control the preset voltage to be maintained (constant voltage control function) upon discharging from the storage parts  12  or  21 .  
      In the above-mentioned aspect, the storage part  12  of the charger  10  is charged in advance from the direct current source  11 . By providing the induction rod  20  to the charger  10 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  10  is charged rapidly into the storage part  21  of the induction rod  20 . According to this embodiment, the storage part  21  was a fully charged state in 10 seconds, and could be used for 3 hours.  
      Upon charging from the storage part  12  of the charger  10 , when the storage part  21  does not reach to the rated voltage, the charge circuit is switched with the switch  17  to charging from the direct current source  11 , and electricity keeps supplied from the direct current source  11  until reaching to the rated voltage, and the charge is completed. In this case, the switching timing from the charge from the storage part  12  of a charger  10  to the direct current source  11  is preferably right before the current value of the storage part  12  becomes below the rated current value of the direct current source  11 .  
      In the above-mentioned case, only an electric double-layer capacitor (or an electrochemical capacitor) is the storage part  12  of a charger  10 , and since an electric double-layer capacitor (or an electrochemical capacitor) of large capacity is needed to charge the storage part  21  at the cordless instrument side, the charger  10  is made large in scale, and the cost is raised in some cases. On the other hand, in case that the capacity of an electric double-layer capacitor (or an electrochemical capacitor) is made small, the direct current source  11  of large capacity is needed to charge the storage part  21  at the cordless instrument side. Therefore, the capacities of the storage part  12  and the direct current source  11  are to be in appropriate combination depending on the charging condition.  
      Also, in comparison of the storage part  21  at the cordless instrument side and the storage part  12  of a charger  10 , the voltage of the storage part  12  of a charger  10  is preferably higher. The larger the voltage difference, the higher is the charging speed. As for capacity, that of the storage part  12  of a charger  10  is preferably higher, but it is no problem unless extremely smaller, for additional charging is possible from the direct current source  11 .  
      In comparison of the direct current source  11  and the storage part  12  built in a charger  10 , the voltage of the direct current source  11  is preferably higher than the charge voltage of the storage part  12 . Its current value is preferably 2 to 50 A, and more preferably 5 to 30 A. If it is lower than 2 A, the charging time to the storage part  12  built in a charger  10  or the storage part  21  at the cordless instrument side becomes long. If higher than 50 A, the electric source becomes large in scale resulting in high cost.  
      (Second Embodiment) Next, the second embodiment of the present invention is explained.  
       FIG. 5  illustrates the structure of a cordless instrumental system including a charger  10  and an induction rod  20  in accordance with the second embodiment. As the electrochemical capacitor in the storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  10  is 12V, 5 A, and the electric double-layer capacitor of the storage part  12  is 5 series/4 parallel of 2.3V-60 F, and is 11.5V-48 F. Especially in this case, the second charge and discharge control circuit  18  is included in the charger  10 .  
      In the second embodiment, the storage part  12  of a charger  10  is charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  10 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  10  is charged rapidly into the storage part  21  of the induction rod  20 . According to this embodiment, the storage part  21  was a fully charged state in 10 seconds, and could be used for 3 hours.  
      (Third Embodiment) Next, the third embodiment of the present invention is explained.  
       FIG. 6  illustrates a structure of a cordless instrumental system including a charger  10  and an induction rod  20  in accordance with the third embodiment. As the electrochemical capacitor in the storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  10  is 12V, 5 A, and the electrochemical capacitor of the storage part  12  is 5 series/2 parallel of 2.3V-120 F, and is 11.5V-48 F. Especially in this case, the storage part  12  of a charger  10  is constituted with an electrochemical capacitor.  
      In the third embodiment, the storage part  12  of a charger  10  is charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  10 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  10  is charged rapidly into the storage part  21  of the induction rod  20 . According to this embodiment, the storage part  21  was a fully charged state in 10 seconds, and could be used for 3 hours.  
      (Fourth Embodiment) The fourth embodiment of the present invention is explained.  
       FIG. 7  illustrates a structure of a cordless instrumental system including a charger  10  and an induction rod  20  in accordance with the fourth embodiment. As the electrochemical capacitor in the storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  10  is 12V, 5 A, and the electric double-layer capacitor of the storage part  12  is 3 units connected in parallel, each unit being 5 series/3 parallel of 2.3V-60 F, being 11.5V-48 F. Especially in this case, the plural storage parts  12  of a charger  10  are connected in parallel, each of which is so constituted to select properly with a switch  19 .  
      In the fourth embodiment, the storage part  12  of a charger  10  is charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  10 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  10  is charged rapidly into the storage part  21  of the induction rod  20 . According to this embodiment, the storage part  21  was a fully charged state in 8 seconds, and could be used for 3 hours.  
      Here, a modified example of the fourth embodiment of the present invention is illustrated in  FIG. 8 . As the electric double-layer capacitor in the storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  10  is 12V, 5 A, and the electrochemical capacitor of the storage part  12  is 5 series/2 parallel of 2.3V-120 F, and is 11.5V-48 F.  
      In the above-mentioned modified example, the storage part  12  of a charger  10  is charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  10 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  10  is charged rapidly into the storage part  21  of the induction rod  20 . According to this embodiment, the storage part  21  was a fully charged state in 6 seconds, and could be used for 1.5 hours.  
      Further in another modified example of the present invention, as the electric double-layer capacitor in the storage part  21 , two of the voltage 2.3V-60 F were connected in parallel. The direct current source  11  of the charger  10  is 12V, 5 A, and the electric double-layer capacitor of the storage part  12  is 5 series/4 parallel of 2.3V-60 F, and is 11.5V-48 F.  
      In the above-mentioned another modified example, the storage part  12  of a charger  10  is charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  10 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  10  is charged rapidly into the storage part  21  of the induction rod  20 . In this example, the storage part  21  was a fully charged state in 6 seconds, and could be used for 1.5 hours.  
      (Fifth Embodiment) The fifth embodiment of the present invention is explained.  
       FIG. 9  illustrates a structural example of a charger  30  in accordance with the fifth embodiment of the present invention. The charger  30  comprises a direct current source  11  to generate direct current by being supplied with electricity from a domestic power source or the like, a storage part (the first storage part)  12  and the third storage part  28  chargeable from said direct current source  11 , and a charge and discharge control circuit (the first charge and discharge control circuit)  13  to control charge and discharge of said storage parts  12  and  28 . These are allocated in a box  14 , and the direct current source  11  is supplied with electricity from a commercial power terminal  15 . At the top of the box  14  is provided a charge terminal  16  connected to the induction rod  20 .  
      In this connection, the concrete structural example of the cordless instrumental system in accordance with the fifth embodiment of the present invention is same as that illustrated in  FIG. 1 , and the internal structure of an inductor as a cordless instrument is same as that illustrated in  FIG. 3 , therefore an explanation is omitted.  
       FIG. 10  illustrates a structure of a cordless instrumental system including a charger  30  and an induction rod  20 . The storage part  21  of said induction rod  20  is constituted with an electrochemical capacitor. The electrochemical capacitor used here is also called a pseudo-capacity capacitor, and is that utilizing the pseudo-capacity by redox reaction with the oxides RuO 2  and IrO 2  of the platinoid elements Ru (rutenium) and Ir (iridium) as electrodes. The capacity twice as large or even more than that per unit volume of an electric double-layer capacitor has already been in practical use. The chargeability and dischargeability of large current are equal to those of an electric double-layer capacitor.  
      In this example as the electrochemical capacitor in the second storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  10  is 12V, 2 A, and the electric double-layer capacitor of the first storage part  12  is 11.5V-24 F by five of 2.3V-60 F connected in series as a unit, and further 2 of these units connected in parallel (hereinafter, such series-parallel connection is simply called 5 series/2 parallel.). Also, a nickel hydrogen battery of the third storage part  28  is used as 4 parallel 4.8V-1600 mAh of 1.2V-1600 mAh.  
      The first charge and discharge control circuit  13  and the second charge and discharge control circuit  22  control the voltage not to exceed the preset voltage (rated voltage) (overvoltage control function) upon charging the storage parts  12  or  21 , respectively, and also control the preset voltage to be maintained (constant voltage control function) upon discharging from the first and the second storage parts  12  or  21 .  
      In the above-mentioned aspect, the first and the third storage parts  12  and  28  of a charger  30  are charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  30 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  30  is charged rapidly into the second storage part  21  of the induction rod  20 . And right after that, the first storage part  12  is charged from the third storage part  28 . According to this embodiment, the storage part  21  was a fully charged state in 15 seconds, and could be used for 3 hours.  
      Upon charging from the first storage part  12  of a charger  30 , if the second storage part  21  does not reach to the rated voltage, the charge circuit is controlled with the switch  17  to charge from the direct current source  11 . And electricity keeps supplied into the second storage part  21  from the direct current source  11  till reaching the rated voltage, and the charge is completed. In this case, the switching timing from the charge from the first storage part  12  of a charger  30  to the direct current source  11  is preferably right before the current value of the first storage part  12  becomes just below the rated current value of the direct current source  11 .  
      In the above-mentioned case, only an electric double-layer capacitor (or an electrochemical capacitor) is the first storage part  12  of a charger  30 , and since an electric double-layer capacitor (or an electrochemical capacitor) of large capacity is needed to charge the second storage part  21  at the cordless instrument side, the charger  30  is made large in scale, and the cost is raised in some cases. On the other hand, when the capacity of an electric double-layer capacitor (or an electrochemical capacitor) is made small, the direct current source  11  of large capacity is needed to charge the storage part  21  at the cordless instrument side. In order not to make large the first storage part  12  and direct current source  11 , the third storage part  28  is quite effective. Therefore, the capacities of the storage parts  12  and  28 , and the capacity of direct current source  11  are to be in appropriate combination depending on the charging condition.  
      Also, in comparison with the storage part  21  at the cordless instrument side and the storage part  12  of a charger  30 , the voltage of the storage part  12  of a charger  30  is preferably higher. The larger the voltage difference, the higher is the charging speed. As for capacity, that of the storage part  12  of a charger  30  is preferably higher, but it is no problem unless extremely smaller, for additional charging is possible from the direct current source  11 .  
      In comparison with the direct current source  11  and the first and the third storage parts  12  and  28  built in a charger  30 , the voltage of the direct current source  11  is preferably higher than the charge voltage of the storage parts  12  and  28 . Its current value is preferably 1 to 10 A, and more preferably 1.5 to 6 A. If it is lower than 1 A, the charging time to the storage part  12  built in a charger  10  or the storage part  21  at the cordless instrument side becomes long. If higher than 6 A, the electric source becomes large in scale resulting in high cost.  
      (Sixth Embodiment) Next, the sixth embodiment of the present invention is explained.  
       FIG. 11  illustrates the structure of a cordless instrumental system including a charger  30  and an induction rod  20  in accordance with this embodiment. As the electrochemical capacitor in the storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  30  is 12V, 2 A, and the electric double-layer capacitor of the first storage part  12  is 11.5V-48 F, the units connected in 5 series/4 parallel, each unit being 2.3V-24 F. A nickel hydrogen battery of the third storage part  28  is 4 of 1.2V-1600 mAh connected in series and in total 4.8V-1600 mAh. Especially in this case, the second charge and discharge control circuit  18  is included in a charger  10 .  
      In the sixth embodiment, the first and the third storage parts  12  and  28  of a charger  30  are charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  30 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  30  is charged rapidly into the storage part  21  of the induction rod  20 . Right after it, the storage part  12  is charged from the storage part  28 . According to this embodiment, the storage part  21  was a fully charged state in 15 seconds, and could be used for 3 hours.  
      (Seventh Embodiment) Next, the seventh embodiment of the present invention is explained.  
       FIG. 12  illustrates the structure of a cordless instrumental system including a charger  30  and an induction rod  20  in accordance with this embodiment. As the electrochemical capacitor in the second storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  30  is 12V, 5 A, and the electrochemical capacitor of the first storage part  12  is 11.5V-48 F, the units connected in 5 series/2 parallel, each unit being 2.3V-120 F. Especially in this case, the storage part  12  in the charger  30  is made up of electrochemical capacitors.  
      In the seventh embodiment, the first and the third storage parts  12  and  28  of a charger  30  are charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  30 , the charge terminals  16  and  27  are connected. At first the charged electricity in the first storage part  12  of a charger  30  is charged rapidly into the second storage part  21  of the induction rod  20 . Right after it, the first storage part  12  is charged from the third storage part  28 . According to this embodiment, the second storage part  21  was a fully charged state in 10 seconds, and could be used for 3 hours.  
      (Eighth Embodiment) Next, the eighth embodiment of the present invention is explained.  
       FIG. 13  illustrates the structure of a cordless instrumental system including a charger  30  and an induction rod  20  in accordance with this embodiment. As the electrochemical capacitor in the second storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  10  is 12V, 5 A, and the electric double-layer capacitor of the first storage part  12  is 3 units connected in parallel, each unit being 5 series/3 parallel of 2.3V-60 F, being 11.5V-36 F. Especially in this case, the plural storage parts  12  of a charger  30  is connected in parallel, each of which is so constituted as to select properly with a switch  19 .  
      In the eighth embodiment, the storage parts  12  and  28  of a charger  30  are charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  30 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  30  is charged rapidly into the storage part  21  of the induction rod  20 . Right after it, the storage part  12  is charged from the storage part  28 . According to this embodiment, the storage part  21  was a fully charged state in 8 seconds, and could be used for 3 hours.  
      Here,  FIG. 14  illustrates a modified example of the eighth embodiment. As the electric double-layer capacitor in the second storage part  21 , two of the voltage 2.3V-120 F were connected in parallel. The direct current source  11  of the charger  30  is 12V, 5 A, and the electrochemical capacitor of the first storage part  12  is 11.5V-48 F, the units connected in 5 series/2 parallel, each unit being 2.3V-120 F.  
      In this modified example, the storage parts  12  and  28  of a charger  30  are charged in advance from the direct current source  11 . By attaching the induction rod  20  to the charger  30 , the charge terminals  16  and  27  are connected. At first the charged electricity in the storage part  12  of a charger  30  is rapidly charged into the storage part  21  of the induction rod  20 . Right after it, the storage part  12  is charged from the third storage part  28 . According to this embodiment, the storage part  21  was a fully charged state in 6 seconds, and could be used for 1.5 hours.  
      (Ninth Embodiment) Next, the ninth embodiment of the present invention is explained in detail referring to a figure.  
       FIG. 15  is an external diagonal view illustrating a concrete structural example of a cordless instrumental system in accordance with the ninth embodiment of the present invention. According to this embodiment, a cordless instrument is so constituted as to have an induction rod  40  detachable from a charger  31 , and to be charged with said induction rod  40  attached to the charger  31 . The luminous part  42  of the induction rod  40  is lit on and off by the switch  41 .  
       FIG. 16  is a cross-sectional view illustrating the structural example of the outline of a charger  31  shown in  FIG. 15 . The charger  31  comprises a direct current source  32 , the first and the third storage parts  33  and  34  chargeable from said direct current source  32 , and a charge and discharge control circuit  35 . The direct current source  32  generates direct voltage and current by being supplied with electricity from commercial power source or others. These are allocated in a box  36 , and the direct current source  32  is supplied with commercial electricity from a commercial power terminal  37 . At the top of the box  36  is provided a charge terminal  38  connected upon attaching and detaching of the induction rod  40 .  
       FIG. 17  is a cross-sectional view illustrating the outline of the structural example of an induction rod shown in  FIG. 15 . The induction rod  40  is shaped as a stick, and includes the second and the fourth storage parts  43  and  44 , and a discharge control circuit  45  to control discharge of said storage parts  43  and  44 . Inside a luminous part  42  are provided, for example, light emitting diodes (LED)  47  is series as a plurality of light sources to a retainer  46  as the supporting means. In this structural example, eight LED in total ( 47   a - 47   h ), four each in each of two rows are provided in series. The LED  47  is lit on and off by the switch  41 . Also, a charge terminal  38  detachable from a charger  31  for connection is provided at the right end of the induction rod in  FIG. 17 , which is a cross-sectional view rotated by 90 degrees with respect to  FIG. 15 .  
      Next, the operation of a cordless instrumental system is explained in accordance with the ninth embodiment in which the present invention is applied.  
       FIG. 18  is a block diagram illustrating the circuit structure of the cordless instrumental system including a charger  31  and an induction rod  40  in accordance with the ninth embodiment of the present invention. In  FIG. 18 , the region surrounded by dotted line shows the charger  31 , and that surrounded by single dot chain line shows the induction rod  40 . The charger  31  and the induction rod  40  are connected with charge terminals  38  ( 38   a ,  38   b ,  38   c ) and  48  ( 48   a ,  48   b ,  48   c ). The charger  31  is comprises direct current source  32 , charge and discharge control circuit  35 , and the first and the third storage parts  33  and  34 , and others.  
      Here, the charge and discharge control circuit  35  comprises the charge control circuit  50  of the first storage part, the charge control circuit  51  of the third storage part, the charge control circuit  52  of the fourth storage part, and switching means  53 ,  54 ,  55 , and  56 , and others. The induction rod  40  comprises the switch  41  for on and off of LED  47 , the second and the fourth storage parts  43  and  44 , discharge control circuit  45 , LED  47 , and others.  
      First in the circuit structure of the charger  31 , the charge circuit to the first storage part  33  is explained. The charge and discharge control circuit  35  outputs control signal S 1  to control the switch  53 , and commercial power source  39  connects the output V 0  from the direct current source  32  connected thereto to the first storage part  33 , and charges said first storage part  33 . In case at the switch  53  of illustration in the figure, a switch  53   a  connects the plus terminal of direct current source  32  and the charge control circuit of the first storage part  50 , and a switch  53   b  connects the minus terminal of direct current source  32  and the minus terminal of the first storage part  33 . Relays and others can be used as the switch  53 . The charge and discharge control circuit  35  is given information signal S 2  about charge voltage and current of the first storage part  33 .  
      The charge and discharge control circuit  50  of the first storage part is connected between the direct current source  32  and the first storage part  33 . For the control in this case, the charge voltage control and overcurrent protection control to prevent overvoltage of the first storage part  33  are included. The charge and discharge control circuit  50  conducts charge control of the first storage part  33  based on the charge voltage of the first storage part  33  until the voltage reaches to a fully charged state of voltage V 1 . Here, IC (integrated circuit) or others having the constant voltage control function can be used as the charge control circuit  50  of the first storage part.  
      Next, a charge to the third storage part  34  is explained. When the charge to the first storage part  33  is finished, the charge and discharge control circuit  35  outputs control signal S 1 , and connects the switch  53  to B side shown with dotted line in the figure. Here, a switch  53   a  connects the plus terminal of direct current source  32  to one end of a switch  54 . A switch  53   b  connects the minus terminal of direct current source  32  to the ground. Consequently, the minus terminal of direct current source  32  and the minus terminal of the third storage part  34  connected to the ground are connected. Here, the charge and discharge control circuit  35  lets on the switch  54  by outputting the output signal S 3  to let on the switch  54 , thereby connects the plus terminal of direct current source  32  and the charge control circuit of the third storage part  51 . As such a switch  54 , semiconductor switching devices such as bipolar transistor and MOSFET and relays can be used. By the actions of these switches  53  and  54 , the direct current source  32  is connected to the third storage part  34  via the charge control circuit  51  of the third storage part. Said charge and discharge control circuit  35  is given information signal S 4  about charge voltage and current of the third storage part  34 .  
      For the control of charge control circuit  51  of the third storage part  34 , charge voltage control and overcurrent protection control to prevent overvoltage of the third storage part  34  are included. The charge control circuit  51  of the third storage part conducts charge control of the third storage part  34  based on the charge voltage of the third storage part  34  until the voltage reaches to a fully charged state of voltage V 2 . IC (integrated circuit) or others having the constant voltage control function can be used as the charge control circuit  51  of the third storage part.  
      Next, the circuit to charge the second storage part  43  provided inside the induction rod  40  is explained. When the charge to the first and the third storage parts  33  and  34  is finished, the charge and discharge control circuit  35  outputs control signal S 1  to operate the switch  53  not to connect direct current source  32  to the first and the third storage parts  33  and  34 . Next, the charge and discharge control circuit  35  lets off the switch  55  by outputting the output signal S 5 , and further lets on the switch  56  by outputting the output signal S 6 . As such switches  55  and  56 , semiconductor switching devices such as bipolar transistor and MOSFET and relays can be used. By these, the voltage of the first and the third storage parts  33  and  34  connected in series is applied to the second storage part  43  inside the induction rod  40 .  
      In order to prevent overvoltage of the second storage part  43 , the charge and discharge control circuit  35  is provided with information signal S 7  about charge voltage of the second storage part  43 . When the charge voltage signal S 7  reaches to a fully charged state of V 3 , the charge and discharge control circuit  35  outputs the signal S 6  to let switch  56  from on to off, and stops charging to the second storage part  43 . Here, the first storage part  33  is about in the state of discharging.  
      Next, the charge circuit for the fourth storage part  44  provided inside the induction rod  40  is explained. When the charge to the second storage part  43  is finished, the charge and discharge control circuit  35  outputs control signal S 6  to let off the switch  53  and then outputs control signal S 5  to let on the switch  55 . Thereby, electricity charged in the third storage part  34  charges the fourth storage part  44  inside the induction rod  40 .  
      In order to prevent overvoltage of the fourth storage part  44 , the charge and discharge control circuit  35  is provided with information signal S 8  about charge voltage and current of the fourth storage part  44 . For the control of charge control circuit  52  of the fourth storage part  44 , charge voltage control and overcurrent protection control to prevent overvoltage of the fourth storage part  44  are included. The charge control circuit  52  of the fourth storage part  44  conducts charge control based on the charge voltage of the fourth storage part  44  until the voltage reaches to a fully charged state of V 4 . IC or others having the constant voltage control function can be used as the charge control circuit  52  of the fourth storage part  44 .  
      As described above, the first and the third storage parts  33  and  34  inside the charger  31  are fully charged state by use of direct current source  32 . And next, the second and the fourth storage parts inside the induction rod fully charged by use of the first and the third storage parts  33  and  34 . In this state, the induction rod  40  is detached from the charger  31 , and can be used as cordless.  
      Next, the circuit operation of the induction rod used as cordless is explained. When the switch  41  is on, the discharge control circuit  45  drives LED  47  by using the electricity charged in the second storage part  43 . And when the voltage of the second storage part  43  becomes below the voltage needed to drive LED  47 , the discharge control circuit  45  switches from the second storage part  43  to the fourth storage part  44  to drive LED  47 .  
      In this case, the discharge control circuit  45  is provided with the voltage monitoring function of the second and the fourth storage parts  43  and  44 , and constant voltage controlling function to maintain the preset value upon supplying electricity to LED  47 . Also, the discharge control circuit  45  may be capable of such control functions as pulse driven LED&#39;s and lighting on in turn plural LED&#39;s at a certain time intervals.  
      Here, charging to the first and the third storage parts  33  and  34  of the cordless instrumental system of the present invention is explained in more details.  FIG. 19  is a flowchart illustrating the processing of a charge and discharge control circuit  35  controlling the charge of the first and the third storage parts  33  and  34  of a cordless instrumental system in accordance with the present invention.  
      First at step ST 1 , the voltage information of information signal S 2  about the voltage of the first storage part  33  is measured, and at step ST 2 , it is judged whether the voltage of information signal S 2  is charged or not to charge voltage V 1  preset for the first storage part  33 . And at step  2 , if the voltage is judged as not to have reached to the preset charge voltage V 1  for the first storage part  33 , then it goes back to step ST 3  to charge the first storage part  33 . On the other hand, if the first storage part  33  is judged as charged to the preset charge voltage V 1 , then at step ST 4 , charging of the third storage part  34  begins.  
      And at step ST 5 , the voltage of information signal S 2  is judged whether or not discharged below the preset charge voltage V 1  for the first storage part  33 . And at step ST 6 , if judged as not to have reached to the preset charge voltage V 1  for the first storage part  33 , then it goes back to step ST 3  to charge the first storage part  33 .  
      Next at step ST 7 , voltage of information signal S 4  about the voltage of the third storage part  34  is measured, and at step ST 8 , it is judged whether the voltage of information signal S 4  is charged or not to charge voltage V 2  preset for the third storage part  34 . And at step  8 , if the voltage is judged as not to have reached to the preset charge voltage V 2  for the third storage part  34 , then it goes back to step ST 4  to charge the third storage part  34 . On the other hand at step ST 8 , if the third storage part  34  is judged as charged to the preset charge voltage V 2 , then at step ST 9 , charging of the third storage part  34  is stopped and goes back to step ST 1 .  
      Thus, a charge and discharge control circuit  35  conducts charge and discharge control of the first and the third storage parts  33  and  34 .  
      Next, charging to the second and the fourth storage parts  43  and  44  of the cordless instrumental system of the present invention is explained in more details.  FIG. 20  is a flowchart illustrating the processing of a charge and discharge control circuit controlling the charge of the second and the fourth storage parts  43  and  44  of a cordless instrumental system in accordance with the present invention.  
      First at step ST 11 , the voltage of information signal S 7  about the voltage of the second storage part  43  is measured, and at step ST 12 , it is judged whether the voltage of information signal S 7  is charged or not to charge voltage V 3  preset for the second storage part  43 . And at step  12 , if the voltage is judged as not to have reached to the preset charge voltage V 3  for the second storage part  43 , then it goes back to step ST 13  to charge the second storage part  43 . On the other hand at step ST 12 , if the second storage part  43  is judged as charged to the preset charge voltage V 3 , then at step ST 14 , charging of the fourth storage part  44  begins.  
      And at step ST 15 , the voltage of information signal S 7  is judged whether or not discharged below the preset charge voltage V 3  for the second storage part  43 . And at step ST 16 , if judged as not to have reached to the preset charge voltage V 3  for the second storage part  43 , then it goes back to step ST 13  to charge the second storage part  43 .  
      Next at step ST 17 , voltage of information signal S 8  about the voltage of the fourth storage part  44  is measured, and at step ST 18 , it is judged whether the voltage of information signal S 8  is charged or not to charge voltage V 4  preset for the fourth storage part  44 . At step  18 , if the voltage is judged as not to have reached to the preset charge voltage V 4  for the fourth storage part  44 , then it goes back to step ST 14  to charge the fourth storage part  44 . On the other hand at step ST 18 , if the fourth storage part  44  is judged as charged to the preset charge voltage V 4 , then at step ST 18 , charging of the fourth storage part  44  is stopped.  
      Thus, a charge and discharge control circuit  35  conducts charge and discharge control of the second and the fourth storage parts  43  and  44 .  
      In the above-described aspect, the first storage part  33  of a charger  31  and the second storage part  43  of an induction rod  40  are preferably an electrochemical capacitor or an electric double-layer capacitor. The electrochemical capacitor is also called a pseudo-capacity capacitor, and is that utilizing the pseudo-capacity by redox reaction with the oxides RuO 2  and IrO 2  of the platinoid elements Ru (rutenium) and Ir (iridium) as electrodes. The capacity twice as large or even more than that per unit volume of an electric double-layer capacitor has already been in practical use. The chargeability and dischargeability in large current region of an electrochemical capacitor are equal to those of an electric double-layer capacitor. Also, the third storage part  34  of a charger  31  and the fourth storage part  44  of an induction rod  40  are preferably such batteries as chargeable and dischargeable nickel-hydrogen battery or the like.  
      Here, if only an electric double-layer capacitor or an electrochemical capacitor is used as the first storage part  33  of a charger  31 , and the second storage part  43  and the fourth storage part  44  at the cordless instrument side are charged, then an electric double-layer capacitor or an electrochemical capacitor of large capacity is needed. In this case, charge current is large for rapid charge to the electric double-layer capacitor or others of large capacity, the direct current source  32  of the charger  10  is made large in scale, and the cost is raised in some cases. For this reason, in order not to make the first storage part  33  and the direct current source  32  large in scale, it is effective to use a battery of smaller charge current than an electric double-layer capacitor and others as the third storage part  34 . Therefore, the capacities of the first and the third storage parts  33  and  34  and of the direct current source  32  are to be in appropriate combination depending on the charging and discharging condition of the second and the fourth storage parts  43  and  44  provided to the induction rod  40  as a cordless instrument.  
      Here, the charge voltage V 1  of the first storage part  33  of a charger  31  is preferably higher than the charge voltage V 3  of the second storage part  43  of an induction rod  40 . The larger the voltage difference, the higher is the charging speed. Also, the capacity of the first storage part  33  of a charger  31  is preferably larger than that of the fourth storage part  44  of an induction rod  40  as a cordless instrument, but it is no problem unless extremely smaller, for additional charging is possible from the direct current source  32 .  
      In comparison with the output voltage V 0  of the direct current source  32 , the charge voltage V 1  of the first storage part  33 , and the charge voltage V 2  of the third storage part  34 , the voltage V 0  of the direct current source  32  is preferably higher than the voltages V 1  and V 2 . Also, the output current of the direct current source is preferably such current value as to be capable of rapid charge to the electrochemical capacitor or the electric double-layer capacitor as the first and the second storage parts.  
      In order to apply conventional electrochemical capacitors or electric double-layer capacitors to such mobile type instrument as an induction rod, charge current may be, for example, 1 to 10 A. It may be more preferably about 1.5 to 6 A. In case of mobile instruments, If charge current to an electrochemical capacitor or an electric double-layer capacitor is lower than  1 A, the charging time to the first storage part  33  built in a charger  31  or the second storage part  43  of an induction rod  40  becomes long. If higher than 6 A, the direct current source becomes large in scale resulting in high cost.  
      The cordless instrumental system of the present invention is so constructed, and is used as described bellow. Here, an electrochemical capacitor is used as the first storage part  33  of the charger  31  and the second storage part  43  of an induction rod  40 , and a nickel-hydrogen battery is used as a chargeable and dischargeable battery as the third storage part  34  of the charger  31  and the fourth storage part  44  of the induction rod  40 .  
      First, the first and the third storage parts  33  and  34  of the charger  31  are connected to direct current source  32 , respectively, via the charge and discharge control circuit  35 , and are charge in advance to the voltages V 1  and V 2 . Next, the charge terminal  48  of the induction rod  40  is attached to the charge terminal  38  of the charger  31 . Here, the first and the third storage parts  33  and  34  of the charger  31  are connected in series via the charge and discharge control circuit  35 , resulting in the voltage V 1 +V 2 . And the charge and discharge control circuit  35  rapidly charges the second storage part  43  of the induction rod  40  to the voltage V 3  by using the first and the third storage parts  33  and  34  connected in series. The charge and discharge control circuit  35  charges the fourth storage part  44  to the voltage V 4  when the rapid charging of the second storage part  43  is finished.  
      Thus, the second and the fourth storage parts of the induction rod  40  are full charged, and the charge terminal  48  of an induction rod  40  is detached from the charge terminal  38  of the charger  31 . In this state, the induction rod  40  of the cordless instrument can be used as cordless. In this case, the LED drive circuit of the induction rod  40  first controls the lighting of LED  47  with the electrochemical capacitor of the second storage part  43  as the electric source, and next, when the voltage of the electrochemical capacitor becomes lower than the LED drive voltage, it drives LED  47  by using the electricity charged in the nickel-hydrogen battery as the fourth storage part  44 .  
      The cordless instrumental system of the present invention is thus operated, and by connecting the induction rod  40  to the charger  31  and the charger  31  to the commercial power source  37 , the charger  31  and each storage part ( 33 ,  34 ,  43 ,  44 ) of the induction rod  40  are full charged. In this state, the induction rod  40  can be used as cordless. In this case, if the charger  31  is carried around together with the induction rod  40 , the second and the fourth storage parts  43  and  44  of the induction rod  40  can be recharged from the charger  31  when they run out of power. Thereby, since the cordless instrument  40  of the cordless instrumental system of the present invention is provided with rapidly chargeable and dischargeable electric double-layer capacitor or electrochemical capacitor and a battery, it is capable of rapid charging and discharging, and of long life use.  
      According to the ninth embodiment of the above-mentioned cordless instrumental system, concrete examples are described.  
     EXAMPLE 1  
      Inside of the charger  31  was composed as described below. The direct current source was 1.5V, 5 A. The first storage part  33  was 9.2V-30 F with four electrochemical capacitors of 2.3V-120 F connected in series. The volume of one electrochemical capacitor was 10.2 ml (milliliter), and four make 40.8 ml.  
      The third storage part  34  was 12V-1600 mAh with 10 nickel-hydrogen batteries of 1.2V-1600 mAh connected in series. The volume of one nickel-hydrogen battery was 7.4 ml, and 10 make 74 ml.  
      Inside of an induction rod  40  was composed as described below. The second storage part  43  was 9.2V-30 F with four electrochemical capacitors of 2.3V-120 F connected in series. The volume of one electrochemical capacitor was 10.2 ml, and four make 40.8 ml.  
      The fourth storage part  44  was 8.4V-1600 mAh with seven nickel-hydrogen batteries of 1.2V-1600 mAh connected in series. The volume of one nickel-hydrogen battery was 7.4 ml, and seven make 51.8 ml.  
      In this Example 1, the second storage part  43  was a fully charged state in 3 seconds, and the drivable time of LED was 3 hours when only the second storage part  43  was used. And the continuous drivable time of LED was  110  hours when the nickel-hydrogen battery as the full charged fourth storage part  44  was used. Thereby, the volume of the electrochemical capacitor as the second storage part  43  at the induction rod  40  side is assumed as about 78% of the nickel-hydrogen battery as the fourth storage part  44 , and a rapidly chargeable and dischargeable cordless instrumental system was realized.  
     EXAMPLE 2  
      The cordless instrumental system of same composition as in the above-described Example 1 was manufactured, except for the first storage part  33  inside a charger  31  was 9.2V-30 F with two units 4 series/2 parallel connected in parallel with a unit of four 2.3V-60 F electric double-layer capacitor connected in series.  
      In this case, the first storage part  33  inside the charger  31  was a fully charged state in 3 seconds, and the drivable time of LED was 3 hours when only the second storage part  43  was used. And the continuous drivable time of LED was 110 hours when the nickel-hydrogen battery as the full charged fourth storage part  44  was used.  
      The present invention is by no way limited to the above-described embodiments, and needless to say that various modification is possible within the scope of the present invention, which is also included in the range of the present invention. For example, the concrete numerical values of voltage or current or others explained in the embodiments mentioned above are shown as preferable, and can be modified depending on necessities. Also, an induction rod was mainly explained as a cordless instrument in the embodiments described above, but needless to say that the cordless instrumental system of the present invention is applicable to such portable electrical operation instruments as an electric shavers, an electric toothbrushes, small cleaners, electric drills, and others, and such portable informational instruments as personal computers, mobile phones, and PDA (personal digital assistant), and portable instruments handling music or image information using such optical or magnetic discs as CD, MD, and DVD, irrelevant of the kinds of various fields of use, thereby the same effect as the embodiments described above can be achieved.  
     INDUSTRIAL APPLICABILITY  
      As explained above according to the present invention, rapid charging is possible compared with the charging time of conventional secondary batteries, and such merits as long life use, compact size of a charger, and low cost are realized.