Patent Publication Number: US-2022223949-A1

Title: Battery pack and electric device

Description:
TECHNICAL FIELD 
     The present invention relates to a battery pack having a wireless communication function. 
     BACKGROUND ART 
     Patent Literature 1 discloses that information on usage history of an electric device is transmitted to an external device via an adapter having a communication unit to enhance convenience of the electric device. 
     CITATION LIST 
     Patent Literature 
     [Patent Literature 1] 
     
         
         Japanese Patent Application Laid-Open No. 2019-25611 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     The inventors wanted information managed by a microcontroller of a battery pack to be read out to the outside to perform more advanced management. Therefore, mounting a wireless communication mechanism in a battery pack was considered. The wireless communication mechanism can be realized by mounting a module in which an antenna and a microcontroller are incorporated in one chip. Normally, a resin is applied on mounted elements on a circuit board in a battery pack for waterproofing and dustproofing purposes. However, applying something onto an antenna for waterproofing and dustproofing purposes can cause a likelihood of it becoming a shield and should be avoided as far as possible. On the other hand, in mass production, there is a concern that demanding detailed restrictions on application of a resin can be a factor that greatly reduces a production efficiency, and at the same time may increase a rate of defects and increase individual differences in the performance of finished products. 
     The present invention has been made in view of the above-described background, and an objective of the present invention is to provide a battery pack in which a wireless communication unit is mounted at an optimum position. Another objective of the present invention is to provide a battery pack that can effectively achieve dustproofing and waterproofing of a wireless communication unit. Still another objective of the present invention is to provide a battery pack in which an assembly efficiency of a substrate on which a wireless communication unit is mounted is improved. 
     Solution to Problem 
     Typical features of the invention disclosed in the present application will be described as follows. According to one feature of the present invention, a battery pack includes a case which accommodates a plurality of battery cells, a positive electrode terminal and a negative electrode terminal connected to the battery cells, a wireless communication unit which performs wireless communication with an external device, a wireless control circuit which controls the wireless communication unit, and a circuit board on which the wireless communication unit is mounted, in which the wireless communication unit includes a wireless communication circuit and an antenna wire extending along a surface of the circuit board from the wireless communication circuit, and a sealing member is provided around the wireless communication unit in a surface direction. Then, a resin layer covering a soldered portion of mounted electronic elements is formed in a region of the circuit board other than the sealing member. The sealing member includes a frame part covering a periphery of the wireless communication unit in the surface direction and a lid part covering the frame part and accommodates the wireless communication circuit and the antenna wire inside the sealing member by positioning an opening surface of the frame part to be in contact with the circuit board. Further, a sealing member having a higher transmittance to radio waves in a used frequency band than the resin layer may be selected as the sealing member. 
     According to another feature of the present invention, a battery pack includes a case which accommodates a plurality of battery cells, a positive electrode terminal and a negative electrode terminal connected to the battery cells, a wireless communication unit which performs wireless communication with an external device, a wireless control circuit which controls the wireless communication unit, and a circuit board on which the wireless communication unit is mounted, in which the wireless communication unit includes a wireless communication circuit and an antenna wire extending along a surface of the circuit board from the wireless communication circuit, a rubber sheet member covering an upper surface of the wireless communication unit is provided, and a resin layer covering a soldered portion of mounted electronic elements is formed in a region of the circuit board other than the rubber sheet member. The rubber sheet member includes a notch formed to expose a portion of the antenna wire to the outside. Also, the resin layer is formed in an outer edge portion of the rubber sheet member at a part of an outer surface of a rubber sheet on a side opposite to the circuit board. 
     According to still another feature of the present invention, a plurality of connection terminal groups including a positive electrode terminal and a negative electrode terminal is disposed to be aligned in a left-right direction on the circuit board, and the wireless communication unit is mounted on a front side of the circuit board in a mounting direction with the connection terminal groups as a reference. Also, the resin layer is formed by applying silicone, and the connection terminal groups except for leg parts are exposed from the resin layer to the outside. Further, the wireless communication unit is configured to include the wireless communication circuit incorporated in a microcontroller and an antenna unit connected to the microcontroller, and the antenna unit is disposed on a front side of the microcontroller when viewed in the mounting direction. 
     Advantageous Effects of Invention 
     According to the present invention, since the wireless communication device and the antenna were mounted at a specific position on the circuit board of the battery pack, a disposition avoiding the vicinity of the metal terminals and the back of the board as far as possible could be realized, and deterioration in antenna efficiency from characteristics of radio waves could be suppressed. Also, it is possible to achieve waterproofing and dustproofing by forming the resin layer while avoiding the antenna portion. Further, although the assembly process for mounting the sealing member in the vicinity of the antenna or stretching the rubber sheet member increases, workability is better than that in application work under the above detailed restrictions, human error can be reduced, and this thereby leads to an improved accuracy in production. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an overall schematic view of a management system using a battery pack  100  according to an example of the present invention. 
         FIG. 2  is a perspective view of the battery pack  100  according to the example of the present invention. 
         FIG. 3  is a perspective view of a power tool main body  1  to which the battery pack  100  according to the present invention is to be mounted. 
         FIG. 4  is an exploded perspective view of the battery pack  100  of  FIG. 3 . 
       (A) of  FIG. 5  is a partial perspective view illustrating shapes of positive electrode terminals ( 162  and  172 ) and negative electrode terminals ( 167  and  177 ) of the battery pack  100  and a view illustrating a connection circuit at the time of high voltage output, and (B) of  FIG. 5  is a partial perspective view illustrating a connection status between a terminal part  50  of a high voltage electric device and terminals on the battery pack  100  side. 
       (A) of  FIG. 6  is a partial perspective view illustrating shapes of the positive electrode terminals ( 162  and  172 ) and the negative electrode terminals ( 167  and  177 ) of the battery pack  100  and a view illustrating a connection circuit at the time of low voltage output, and (B) of  FIG. 6  is a partial perspective view illustrating a connection status between a terminal part  80  of a low voltage electric device and terminals on the battery pack  100  side. 
         FIG. 7  is an exploded perspective view for explaining a status of stacking and a method of wiring battery cells using a separator  245  of  FIG. 4 . 
         FIG. 8  is a block diagram showing a basic internal circuit of the battery pack  100 . 
         FIG. 9  is a circuit diagram of an electric device for high voltage to which the battery pack  100  of an automatic voltage switching type is connected. 
         FIG. 10  is a side view of the separator  245  after the parts illustrated in  FIG. 5  are assembled, in which (A) of  FIG. 10  is a right side and (B) of  FIG. 10  is a left side view. 
         FIG. 11  is a perspective view illustrating a state in which a circuit board  150  is fixed to the separator  245  (perspective view seen from the above left front). 
         FIG. 12  is a perspective view illustrating a state in which the circuit board  150  is fixed to the separator  245  (perspective view seen from the above right rear). 
         FIG. 13   FIG. 16  is a view for explaining a method of connecting lead-out plates  261 ,  266 ,  271 , and  276  to the positive electrode terminals ( 162  and  172 ) and the negative electrode terminals ( 167  and  177 ) in the battery pack  100 . 
         FIG. 14  is a top view of the circuit board  150  of the battery pack  100  according to the present invention. 
         FIG. 15  is a top view illustrating a state in which a module of wireless communication is removed in the circuit board  150  of  FIG. 14 . 
         FIG. 16  is a cross-sectional view along line A-A of the circuit board  150  of the battery pack  100  of  FIG. 14 . 
         FIG. 17  is a front view of the circuit board  150  of the battery pack  100  of  FIG. 14 . 
         FIG. 18  is a view illustrating a status of silicone application on the circuit board  150  of the battery pack  100  according to the present invention. 
         FIG. 19  is a perspective view of a frame body  281  of  FIG. 18 . 
         FIG. 20  is a view illustrating a status of silicone application on the circuit board  150  by a method different from that of  FIG. 18 . 
         FIG. 21  is a partial enlarged view illustrating a configuration in which the frame body  281  is covered with an upper case  110 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Example 1 
     Hereinafter, examples of the present invention will be described on the basis of the drawings. In the following figures, the same portions will be denoted by the same reference signs, and repeated description will be omitted. In the present specification, description will be made using a power tool operated by a battery pack as an example of an electric device. 
       FIG. 1  is an overall schematic view of a management system using a battery pack  100  according to an example of the present invention. A power tool main body  1  is a portable electric device that can use a battery pack  100 - 1  as a power supply and is an impact tool that is widely used conventionally. The battery pack  100  of the present example includes a microcontroller mounted therein and Bluetooth (Bluetooth: Bluetooth SIG, Inc. USA registered trademark) that enables near-field wireless communication with the microcontroller. Since the wireless communication device is mounted inside the battery pack  100  in this way, wireless communication of the battery packs  100 - 1  to  100 - 3  with a terminal device  301 , which is an external device, is possible bidirectionally. The terminal device  301  not only can communicate with the battery pack  100 - 1  in a state of being mounted in the power tool main body  1  but also can communicate with the battery packs  100 - 2  and  100 - 3  in a state of being removed from electric devices such as the power tool main body  1 . 
     The battery packs  100 - 1  to  100 - n  are those in which a plurality of lithium-ion battery cells each having a rated voltage of 3.6 V is connected in series so that a DC current of, for example, 18 V or 36 V can be selectively output. Some models of the power tool (not illustrated) on a side to which the battery pack  100  is mounted include Bluetooth (registered trademark). In that case, there are also cases in which the terminal device  301  can indirectly acquire information of the battery pack  100  when the terminal device  301  is connected to the power tool. However, in the present example, the battery pack  100  and the terminal device  301  directly communicate with each other, and thereby the terminal device  301  can read information of the battery pack  100  regardless of whether the battery pack  100  is mounted on a power tool or the battery pack  100  is removed from a power tool. 
     The battery packs  100 - 1  to  100 - 3  are battery packs of the same model and the same capacity but are not limited to the same battery pack  100  and may be battery packs having various voltages and capacities of different types. However, it is important that each battery pack  100  includes a processor for managing batteries and a wireless communication device therein. As the terminal device  301 , for example, a smartphone sold by a telephone company can be used. The terminal device  301  can be connected to a base station  360  of a telephone company using a telephone communication network  361  and can be connected to a server device of a manufacturer of the battery pack  100  or a support company  300  using a network  350  such as the Internet. Therefore, the terminal device  301  can transmit information received from the battery packs  100 - 1  to  100 - 3  to the server device of the support company  300  and can receive some information from the terminal device  301  and display it on a display screen  302 . Further, the terminal device  301  can perform wireless communication with a specific battery pack (for example,  100 - 2 ) using a wireless communication device and write information to the microcontroller of the battery pack  100 - 2 . 
     The battery pack  100  (for example,  100 - 1 ) performs a pairing with the terminal device  301 . “Pairing” is an operation of associating and registering the terminal device  301  and the battery pack  100  side using wireless communication, and when a registration operation (pairing) of these is performed, the terminal device  301  can acquire necessary information from the paired battery pack  100 . A relationship between the pairing partners may be “terminal device:number of battery packs=1:1 but may also be 1:n (n is a natural number) as illustrated in the figure. The number n which can be paired depends on a wireless communication standard used. Also, all of the owned battery packs that can be wirelessly connected may be paired at the same time, but all of them need not necessarily be paired at the same time, and only the target battery pack  100  for which a status thereof is desired to be checked may be selected and paired. 
     The terminal device  301  processes information received from the battery pack  100  by wireless communication and acquires a state of the battery pack  100 , particularly usage states of various types such as the number of times of charging, the number of times of overcharging, the number of times of over-discharge, types of power tool to which it has been mounted, and voltage recording at the time of use to ascertain a present state of the battery pack  100 . Data of the ascertained information is transmitted to the support company  300  via the telephone communication network  361  and the network  350 . In order to enable wireless communication with the battery pack  100 , dedicated software, so-called application software, is installed in the terminal device  301 . Further, the terminal device  301  is not limited to a so-called smartphone and may be a tablet type personal computer (PC), a general-purpose PC, or the like as long as bidirectional or unidirectional wireless communication with the wireless communication device on the battery pack  100  side is possible. 
       FIG. 2  is a perspective view of the battery pack  100  according to the example of the present invention. The battery pack  100  is a “voltage variable battery pack” in which two sets of cell units each having five 3.6 V lithium-ion battery cells connected in series are accommodated, and the two of 18 V output (low voltage output) and 36 V output (high voltage output) can be switched between by changing a connection method of the two sets of cell units. 
     A housing of the battery pack  100  is formed by a lower case  101  and an upper case  110  that can be separated from each other in a vertical direction. The upper case  110  includes a mounting mechanism in which two rails  138   a  and  138   b  are formed for mounting to a battery pack mounting part  2   c  (to be described later in  FIG. 3 ) of the power tool main body  1 . The rails  138   a  and  138   b  are formed to extend in a direction parallel to a direction in which the battery pack  100  is mounted and to protrude to left and right side surfaces of the upper case  110 . The rails  138   a  and  138   b  are formed in a shape corresponding to rail grooves (not illustrated) formed in the battery pack mounting part  2   c  of the power tool main body  1 , and the battery pack  100  is fixed to the power tool main body  1  by locking the rails  138   a  and  138   b  with locking parts  142  which are claws of the latches  141  in a state in which the rails  138   a  and  138   b  are fitted with the rail grooves on the electric device main body side. At the time of removing the battery pack  100  from the power tool main body  1 , when the latches  141  on both the left and right sides are pushed, the locking parts  142  move inward to release the locked state, and thereby the battery pack  100  in that state is moved to a side opposite to the mounting direction. 
     A lower stage surface  111  and an upper stage surface  115  of the upper case  110  are formed to have different heights in a stepwise manner, and a plurality of slots  121  to  128  extending rearward from a connecting portion thereof is formed. The slots  121  to  128  are portions cut out to have a predetermined length in a direction in which the battery pack is mounted, and a plurality of connection terminals (connection terminal groups) that can be fitted with device-side terminals of the power tool main body  1  or an external charging device (not illustrated) is disposed inside the cut-out portions. In the slots  121  to  128 , the slot  121  on a side close to the rail  138   a  on a right side of the battery pack  100  serves as an insertion port for a positive electrode terminal (C+ terminal) for charging, and the slot  122  serves as an insertion port for a positive electrode terminal (+ terminal) for discharging. Also, the slot  127  on a side close to the rail  138   b  on the left side serves as an insertion port for a negative electrode terminal (− terminal). A plurality of signal terminals for transmitting signals to the battery pack  100 , the power tool main body  1 , and an external charging device (not illustrated) is disposed between the positive electrode terminals and the negative electrode terminal, and here, four slots  123  to  126  for the signal terminals are provided between the power terminal groups. The slot  123  is a spare terminal insertion port, and no terminal is provided therefor in the present example. The slot  124  is an insertion port for a T terminal from which a signal serving as identification information of the battery pack  100  is output to the power tool main body or a charging device. The slot  125  is an insertion port for a V terminal to which a control signal from an external charging device (not illustrated) is input. The slot  126  is an insertion port for an LS terminal for outputting battery temperature information by a thermistor (temperature sensing element) (not illustrated) provided in contact with the cell. The slot  128  for an LD terminal which outputs an abnormal stop signal by a battery protection circuit (not illustrated) included in the battery pack  100  is also provided on a left side of the slot  127  serving as the insertion port of the negative electrode terminal (− terminal). 
     A raised part  132  formed to be raised is formed on a rear side of the upper stage surface  115 . A stopper part  131  having a recessed shape is formed near a center of the raised part  132 . The stopper part  131  serves as an abutment surface when the battery pack  100  is mounted on the battery pack mounting part  2   c  (described later with  FIG. 3 ). When the battery pack  100  is mounted at a predetermined position on the power tool main body  1 , the plurality of terminals (device side terminals) disposed in the power tool main body  1  and the plurality of connection terminals disposed in the battery pack  100  are brought into contact with each other to be in a conductive state. A notch part  111   a  for discrimination that is configured to prevent a conventional 18 V battery pack from being mounted on a 36 V power tool main body is formed at a front left corner portion of the lower stage surface  111 . 
       FIG. 3  is a perspective view of the power tool main body  1  to which the battery pack  100  according to the present invention is to be mounted. The power tool main body  1  illustrated here is an impact driver and includes a handle part  2   b  provided to extend downward from a body portion of a housing  2  and a battery pack mounting part  10  formed on a lower side of the handle part  2   b . A trigger switch  4  is provided on the handle part  2   b . An anvil (not illustrated) serving as an output shaft is provided on a front side of the housing  2 , and a distal end tool holding part  8  to which a distal end tool  9  is mounted is provided at a distal end of the anvil. Here, a plus driver bit is mounted as the distal end tool  9 . There is no limitation to electric tools, and general electric devices using a battery pack may be configured to include the battery pack mounting part  10  formed to correspond to a shape of a battery pack to be mounted so that a battery pack that does not fit the battery pack mounting part  10  cannot be mounted. The battery pack mounting part  10  includes rail grooves  11   a  and  11   b  formed to extend parallel to each other in a front-rear direction on inner wall portions on both left and right sides, and a terminal part  20  is provided therebetween. The terminal part  20  is manufactured by integrally molding a non-conductive material such as a synthetic resin, and a plurality of terminals made of a metal, for example, a positive electrode input terminal  22 , a negative electrode input terminal  27 , and an LD terminal (abnormal signal terminal)  28  are cast therein. The terminal part  20  is formed with a vertical surface  20   a  which is an abutment surface in a mounting direction (front-rear direction) and a horizontal surface  20   b , and the horizontal surface  20   b  is a surface adjacent to and facing the upper stage surface  115  (see  FIG. 2 ) when the battery pack  100  is mounted. A curved part  12  that comes into contact with the raised part  132  (see  FIG. 2 ) of the battery pack  100  is formed on a front side of the horizontal surface  20   b , and a protruding part  14  is formed near a left-right center of the curved part  12 . The protruding part  14  serves as a boss for screwing the housing of the power tool main body  1  formed in two parts in a left-right direction and also serves the role of a stopper that restricts relative movement of the battery pack  100  in the mounting direction. 
       FIG. 4  is an exploded perspective view of the battery pack  100  of  FIG. 3 . The housing of the battery pack  100  is formed by the upper case  110  and the lower case  101  that can be separated in a vertical direction, and 10 battery cells are accommodated in an internal space of the lower case  101 . A plurality of battery cells (not illustrated) is fixed by a separator  245  formed of a non-conductor such as a synthetic resin in a state in which five battery cells are each stacked in two stages. The separator  245  holds the plurality of battery cells so that only both left and right sides serving as both end portions of the battery cells are open. 
     A circuit board  150  is fixed on an upper side of the separator  245 . The circuit board  150  fixes a plurality of connection terminals ( 161 ,  162 ,  164  to  168 ,  171 ,  172 , and  177 ) by soldering and electrically connects these connection terminals to a circuit pattern (not illustrated). Various electronic elements (not illustrated here) such as a battery protection IC, a PTC thermistor, a resistor, a capacitor, a fuse, and a light emitting diode are also mounted on the circuit board  150 . Further, a communication module and an antenna (both to be described later) forming a wireless communication device are mounted in an area occupied by a dotted line  152 . A material of the circuit board  150  is one called a printed circuit board in which a pattern wiring is printed with a conductor such as a copper foil on a substrate that has been impregnated with a resin having insulating properties against the material, and a single-layer substrate, a double-sided substrate, or a multi-layer substrate can be used therefor. In the present example, a wiring pattern is formed on an upper surface (a surface which is an upper surface that can be seen from  FIG. 4 ) and a lower surface (back surface) of the circuit board  150  using a double-sided substrate. A connection terminal group  160  is provided slightly in front of a center of the circuit board  150  in a front-rear direction, and a plurality of connection terminals ( 161 ,  162 ,  164  to  168 ,  171 ,  172 , and  177 ) is fixed to be aligned therein in a transverse direction. 
     The positive electrode terminals ( 161 ,  162 ,  171  and  172 ) and the negative electrode terminals ( 167  and  177 ) are disposed at positions greatly separated from each other in a left-right direction, and three signal terminals (T terminal  164 , V terminal  165 , and LS terminal  166 ) are provided between them. In the present example, a total of two sets of arm parts including one set on the upper left and right and one set on the lower left and right which extend in a horizontal direction are used as a part for a power terminal. The LD terminal  168  is provided on a left side of the negative electrode terminal pair ( 167  and  177 ). All the signal terminals ( 164  to  166 , and  168 ) are fixed by soldering on a back surface of the circuit board  150  with leg parts thereof caused to pass through a plurality of mounting holes  151   a  and  151   b  formed in the circuit board  150  from the surface to the back surface. As described above, electronic elements (not illustrated) are mounted on the circuit board  150 , a plurality of connection terminals is fixed by soldering, and then a resin (not illustrated) is applied to the surface of the circuit board  150  for waterproofing and dustproofing. 
     The lower case  101  has a substantially rectangular parallelepiped shape with an upper surface open. Slits  104  are provided substantially at a center of a front wall. Slits  134  of the upper case  110  are used as an inflow port for allowing cooling air sent from a charging device side to flow into an internal space of the battery pack  100  when charging is performed with the charging device, and the slits  104  of the lower case  101  are used as a discharge port for the cooling air. 
     Connection of an output from the battery cell side to the circuit board  150  is performed via lead-out tabs  261   a ,  266   a ,  271   a , and  276   a  for connection extending upward in a plate shape. Also, end portions  294   b ,  296   b  to  299   b  of lead wires from intermediate connection points of the battery cells connected in series are disposed to extend upward and are soldered on the circuit board. Further, intermediate lead-out tabs  262   a  and  263   a  from the intermediate connection points of the battery cells connected in series are disposed to extend upward to be connected to the circuit board  150 . Screw bosses  247   a  and  247   b  for fixing the circuit board  150  are formed on an upper side of the separator  245 . 
     Next, shapes of two sets of the power terminals will be described with reference to  FIG. 5 .  FIG. 5  is a partial view of the circuit board  150  of the battery pack  100 , in which only a positive electrode terminal pair (the upper positive electrode terminal  162  and the lower positive electrode terminal  172 ) and a negative electrode terminal pair (the upper negative electrode terminal  167  and the lower negative electrode terminal  177 ) fixed to the circuit board  150  are illustrated. (A) of  FIG. 5  is a partial perspective view illustrating shapes of the positive electrode terminals ( 162  and  172 ) and the negative electrode terminals ( 167  and  177 ) of the battery pack  100  of the present example and a view illustrating a connection circuit at the time of high voltage output. (B) of  FIG. 5  is a partial perspective view illustrating a connection status between a terminal part  50  of a high voltage electric device and the terminals on the battery pack  100  side. As illustrated in (A) of  FIG. 5 , the upper positive electrode terminal  162  and the lower positive electrode terminal  172  are disposed to be aligned in the slot  122  (see  FIG. 2 ) of the battery pack  100 . The upper positive electrode terminal  162  and the lower positive electrode terminal  172  are formed by press processing of a metal plate, and the leg parts are firmly fixed to the circuit board  150  by soldering or the like. The upper positive electrode terminal  162  and the lower positive electrode terminal  172  are disposed at a distance from each other and are in an electrically non-conductive state. Similarly, the upper negative electrode terminal  167  and the lower negative electrode terminal  177  are disposed to be aligned in the slot  127  (see  FIG. 2 ). The upper positive electrode terminal  162  and the upper negative electrode terminal  167  are the same metal part as each other, and the lower positive electrode terminal  172  and the lower negative electrode terminal  177  are the same metal part as each other. 
     Inside the battery pack  100 , an upper cell unit (first cell unit)  146  and a lower cell unit (second cell unit)  147  in each of which five lithium-ion battery cells are connected in series are accommodated, a positive electrode of the upper cell unit  146  is connected to the upper positive electrode terminal  162  corresponding to a first positive electrode terminal, and a negative electrode of the upper cell unit  146  is connected to the lower negative electrode terminal  177  corresponding to a first negative electrode terminal. Similarly, a positive electrode of the lower cell unit  147  is connected to the lower positive electrode terminal  172  corresponding to a second positive electrode terminal, and a negative electrode of the lower cell unit  147  is connected to the upper negative electrode terminal  167  corresponding to a second negative electrode terminal. In such a form of the battery pack  100 , when a positive electrode input terminal on the power tool main body  1  side is connected to the upper positive electrode terminal  162  and a negative electrode input terminal thereof is connected to the upper negative electrode terminal  167 , and the lower positive electrode terminal  172  and the lower negative electrode terminal  177  are electrically connected as illustrated by a dotted line  59 , an output of the series connection of the upper cell unit  146  and the lower cell unit  147 , that is, a rating of 36 V, is output from the battery pack  100  to a load device  70  of the power tool main body  1 . 
     The positive electrode terminals for output are disposed such that the upper positive electrode terminal  162  and the lower positive electrode terminal  172  that are electrically independent of each other are disposed to be aligned in a front-rear direction when viewed from the mounting position of the circuit board  150 . These are a plurality of terminals ( 162  and  172 ) disposed close to each other, and function as a switching terminal group used for voltage switching. The upper positive electrode terminal  162  and the lower positive electrode terminal  172  have arm part sets (arm parts  162   a  and  162   b , arm parts  172   a  and  172   b ) extending forward. Here, the arm parts  162   a  and  162   b  and the arm parts  172   a  and  172   b  are each at positions away from each other in a vertical direction, and positions of each fitting portion of the arm parts in a front-rear direction are substantially the same as each other. This positive electrode terminal pair ( 162  and  172 ) is disposed in the single slot  122 . The negative electrode terminal pair also has the same shape as the positive electrode terminal pair and is constituted by the upper negative electrode terminal  167  and the lower negative electrode terminal  177 , and this negative electrode terminal pair ( 167  and  177 ) is disposed inside the single slot  127 . These are a plurality of terminals ( 167  and  177 ) disposed close to each other, and function as a switching terminal group used for voltage switching. Inside the slot  127 , an arm part set of the upper negative electrode terminal  167  is disposed on an upper side, and an arm part set of the lower negative electrode terminal  177  is disposed below the arm part set of the upper negative electrode terminal  167 . Although not illustrated in  FIG. 5 , a positive electrode pair for charging (the upper positive electrode terminal  161  and the lower positive electrode terminal  171 ; see  FIG. 4 ) is disposed on a right side of the positive electrode terminal pair for discharging (the upper positive electrode terminal  162  and the lower positive electrode terminal  172 ). The positive electrode terminal pair for charging ( 161  and  171 ) have the same shape as those of the upper positive electrode terminal  162  and the lower positive electrode terminal  172 . 
     (B) of  FIG. 5  is a view illustrating a connection relationship between the terminal part  50  of the power tool main body  1  having a rating of 36 V and the connection terminals ( 162 ,  167 ,  172 , and  177 ) on the battery pack  100  side. The terminal part  50  is provided at the battery pack mounting part  2   c  of the power tool main body  1 . Device-side terminals ( 52 ,  59   a ,  54  to  56 ,  57 ,  59   b , and  58 ) corresponding to the slots  121  to  128  (see  FIG. 2 ) of the battery pack  100  are provided in the terminal part  50  and fixed by casting in a base  51  made of a synthetic resin. In the base  51 , a connection terminal part on an upper side and a plate-shaped terminal part on a lower side having the same reference sign are formed of an electrically conductive metal plate. Here, the device-side terminal is not provided at a position corresponding to the slot  123  (see  FIG. 2 ). As input terminals for power, the positive electrode input terminal  52  and the negative electrode input terminal  57  for receiving power are provided with a small size above short-circuit terminals  59   a  and  59   b . The positive electrode input terminal  52  and the short-circuit terminal  59   a  are not electrically connected. Also, the negative electrode input terminal  57  and the short-circuit terminal  59   b  are not electrically connected. 
     When the battery pack  100  is mounted, the positive electrode input terminal  52  is fitted only to the upper positive electrode terminal  162 , and the negative electrode input terminal  57  is fitted only to the upper negative electrode terminal  167 . Also, the small terminals  59   a  and  59   b  for short-circuiting the lower positive electrode terminal  172  and the lower negative electrode terminal  177  are provided in the terminal part  50  of the power tool main body  1 . The small terminals  59   a  and  59   b  are both end portions of a short circuit  59  and are connected inside the base  51 . 
     The positive electrode input terminal  52  is constituted by a terminal part which is a portion to be fitted with the upper positive electrode terminal  162  and formed in a flat plate shape, and a terminal part which is one to be connected to the circuit board side of the power tool main body  1  side and protruding upward from the base  51 . The positive electrode input terminal  52  is cast into the base  51  made of a synthetic resin. The negative electrode input terminal  57  is configured in the same manner as the positive electrode input terminal  52  and a height of the terminal is of a size slightly smaller than half that of the other terminal parts ( 54  to  56 , and  58 ). The other terminal parts ( 54  to  56 ,  58 ) are terminals for signal transmission. Recessed parts  51   a  and  51   b  for being sandwiched by the housing are provided on a front side and a rear side of the synthetic resin base  51  of the terminal part  50 . 
     In (B) of  FIG. 5 , when the battery pack  100  is mounted, when the battery pack  100  is relatively moved with respect to the power tool main body  1  in an insertion direction, the positive electrode input terminal  52  and the short-circuit terminal  59   b  are inserted into the inside through the same slot  122  (see  FIG. 2 ) and are respectively fitted into the upper positive electrode terminal  162  and the lower positive electrode terminal  172 . At this time, the positive electrode input terminal  52  is press-fitted between the arm parts  162   a  and  162   b  of the upper positive electrode terminal  162  in a manner of pushing and extending between the fitting portions of the upper positive electrode terminal  162 , and the short-circuit terminal  59   b  is press-fitted between the arm parts  172   a  and  172   b  of the lower positive electrode terminal  172  in a manner of pushing and extending therebetween. Similarly, the negative electrode input terminal  57  and the short-circuit terminal  59   b  are inserted into the inside through the same slot  127  (see  FIG. 2 ) and are respectively fitted into the upper negative electrode terminal  167  and the lower negative electrode terminal  177 . At this time, the negative electrode input terminal  57  is press-fitted between the arm parts  167   a  and  167   b  of the upper negative electrode terminal  167  in a manner of pushing and extending between the fitting portions. Further, the short-circuit terminal  59   b  is press-fitted between the arm parts  177   a  and  177   b  of the lower negative electrode terminal  177  in a manner of pushing and extending therebetween. When the connection form of (B) of  FIG. 5  as described above is realized, an output of the series connection of the upper cell unit  146  and the lower cell unit  147 , that is, a rating of 36 V is output from the battery pack  100 . 
     (A) and (B) of  FIG. 6  are views illustrating a connection state when the battery pack  100  of the present example is mounted to the power tool main body  1  (see  FIG. 3 ) for 18 V. When the battery pack  100  is attached to the power tool main body  1 , a terminal part of a positive electrode input terminal  82  is press-fitted in a manner of pushing and extending two opening end portions of the upper positive electrode terminal  162  and the lower positive electrode terminal  172  so that a region of a part of the upper side of the terminal part of the positive electrode input terminal  82  comes into contact with the upper positive electrode terminal  162 , and a region of a part of the lower side thereof comes into contact with the lower positive electrode terminal  172 . When the terminal part of the positive electrode input terminal  82  is simultaneously fitted to the arm parts  162   a  and  162   b  of the upper positive electrode terminal  162  and the arm parts  172   a  and  172   b  of the lower positive electrode terminal  172  as described above, the two positive electrode terminals ( 162  and  172 ) are brought into a short-circuit state. Similarly, a terminal part of a negative electrode input terminal  87  is press-fitted in a manner of pushing and extending two opening end portions of the upper negative electrode terminal  167  and the lower negative electrode terminal  177  so that a region of a part of the upper side of the terminal part of the negative electrode input terminal  87  comes into contact with the upper negative electrode terminal  167 , and a region of a part of the lower side thereof comes into contact with the lower negative electrode terminal  177 . When the terminal part of the negative electrode input terminal  87  is simultaneously fitted to the arm parts  167   a  and  167   b  of the upper negative electrode terminal  167  and the arm parts  177   a  and  177   b  of the lower negative electrode terminal  177  as described above, the two negative electrode terminals ( 167  and  177 ) are brought into a short-circuit state, and an output of the parallel connection of the upper cell unit  146  and the lower cell unit  147 , that is, a rating of 18 V is output to the power tool main body  1 . 
     As described above, the battery pack  100  of the present example is mounted to either the power tool main body  1  for 18 V (see  FIG. 3 ) or the power tool main body for 36 V (not illustrated), and thereby the output of the battery pack  100  is automatically switched. Since the voltage switching is not performed by the battery pack  100  side but is automatically performed according to a shape of the terminal part on the power tool main body  1  side, there is no likelihood that a voltage setting error will occur at all. Also, since it is not necessary to provide a dedicated voltage switching mechanism such as a mechanical switch on the battery pack  100  side, a battery pack having a simple structure, a low likelihood of failure, and a long service life can be realized. 
     When the battery pack  100  is charged using an external charging device (not illustrated), the battery pack  100  can be charged with the same charging device as a conventional battery pack for 18 V. Since the slot  121  of the battery pack  100  includes a positive electrode terminal for charging having the same shape as the upper positive electrode terminal  162  and the lower positive electrode terminal  172 , a positive electrode terminal for charging (not illustrated) may be connected to a positive electrode terminal of an external charging device (not illustrated) instead of the positive electrode terminals for discharging ( 162  and  172 ). 
     Next, a status of stacking and a method of wiring the battery cells using the separator  245  (see  FIG. 4 ) will be described with reference to the exploded perspective view of  FIG. 7 . The separator  245  (see  FIG. 4 ) is a stack of 10 battery cells  146   a  to  146   e  and  147   a  to  147   e  in which five battery cells are each stacked in two upper and lower stages. Although  FIG. 7  illustrates a state in which the battery cells  146   a  to  146   e  and  147   a  to  147   e  are drawn out from the separator  245 , at the time of assembly, they are inserted into a cylindrical space  246  of the separator  245 , terminals exposed on both the left and right sides of the separator are connected to each other by connection plates  262  to  265  and  272  to  275 , and lead-out plates  261 ,  266 ,  271 , and  276  are connected to the battery cells. Thereafter, insulating sheets  278   a  and  278   b  are adhered to the connection plates  262  to  265  and  272  to  275 , and the lead-out plates  261 ,  266 ,  271 , and  276  for insulation. 
     Axes of the battery cells are stacked to be parallel to each other, cells are disposed so that directions of the adjacent cells are alternately reversed, and positive electrode terminals and negative electrode terminals of adjacent battery cells are connected using the metal connection plates  262  to  265  and  272  to  275 . The terminals on both sides of the battery cells and the connection plates  262  to  265  and  272  to  275  are fixed by spot welding at a plurality of positions. Here, the five battery cells connected in series and installed on the upper stage form the upper cell unit  146  (to be described in detail with  FIG. 9 ), and the five battery cells connected in series and installed on the lower side form the lower cell unit  147  (to be described in detail with  FIG. 9 ). 
     For the battery cells  146   a  to  146   e  and  147   a  to  147   e , lithium-ion battery cells (not illustrated) each having a diameter of 18 mm and a length of 65 mm which are called 18650 size and capable of being charged and discharged a plurality of times can be used, but the size and number of battery cells are arbitrary. Two electrodes are provided at both ends in a length direction of the battery cell. Of the two electrodes, one is a positive electrode and the other is a negative electrode. 
     The positive electrode of the upper cell unit  146  is connected to the circuit board  150  using the lead-out plate  261  on which the lead-out tab  261   a  is formed, and the negative electrode of the upper cell unit  146  is connected to the circuit board  150  using a lead-out plate  266  on which the lead-out tab  266   a  is formed. Similarly, the positive electrode of the lower cell unit  147  is connected to the circuit board  150  using the lead-out plate  271  on which the lead-out tab  271   a  is formed, and the negative electrode of the lower cell unit  147  is connected to the circuit board  150  using a lead-out plate  276  on which the lead-out tab  276   a  is formed. Tab holders  250  to  252  and  255  to  257  for holding the tabs of the lead-out plates  261 ,  266 ,  271 , and  276  in a shape of a bent thin metal plate are formed on an upper surface of the separator  245 . The tab holders  250  to  252  and  255  to  257  are tab holding parts formed to hold the lead-out tabs  261   a ,  262   a ,  263   a ,  266   a ,  271   a , and  276   a  bent in an L shape, are integrally formed as a recessed part having a seat surface, a back surface, and both side surfaces when the separator  245  is formed, and the lead-out tabs  261   a ,  262   a ,  263   a ,  266   a ,  271   a , and  276   a  are fitted into the recessed parts. Two screw bosses  247   a  and  247   b  for screwing the circuit board  150  are formed on an upper portion of the separator  245 . Right sides of the lead-out plates  261  and  271  and the connection plates  263 ,  265 ,  273 , and  275  are covered with the insulating sheet  278   a , and a left side of the lead-out plate  266  and  276  and the connection plates  262 ,  264 ,  272 , and  274  are covered with the insulating sheet  278   b . The insulating sheet  278   a  is made of a material that does not conduct electricity, and a sealing material is applied to an inner portion thereof. 
       FIG. 8  is a circuit diagram of the power tool main body (high voltage electric device)  1  to which the battery pack  100  is mounted and has a configuration in which the short circuit (short-circuit path)  59  is incorporated in the power tool main body  1 . The battery pack  100  is shown on the right side, and here, only the necessary configurations are extracted and shown for ease of explanation. In order to take out a voltage of 36 V from the battery pack  100  to the power tool main body  1  having a rating of 36 V, the short circuit  59  indicated by a thick line is provided in the terminal part  50  on the power tool main body  1  side. The short circuit  59  can be formed of a short-circuit element made of a metal plate and can be formed by casting a U-shaped bent metal plate into the base  51  made of a synthetic resin together with other device-side terminals such as the positive electrode input terminal  52  and the negative electrode input terminal  57  as illustrated in  FIG. 5 . One end portion of the U-shaped bent metal plate serves as the short-circuit terminal  59   a , and the other end portion serves as the short-circuit terminal  59   b . When the battery pack  100  is simply mounted to the terminal part  50  having such a shape, DC power having a rating of 36 V is supplied to the positive electrode input terminal  52  and the negative electrode input terminal  57 . The power tool main body  1  includes a microcontroller  60  for controlling rotation of a motor  3 . A voltage (5 V or 3.3 V) for driving the microcontroller  60  is supplied by a power supply device  61  to which a voltage between both ends of the short-circuit terminal  59   a  and the negative electrode input terminal  57  is input. When the terminal part  50  having the short circuit  59  is provided in the power tool main body  1  in this way, a series connection circuit of the upper cell unit  146  and the lower cell unit  147  can be established simply by mounting the battery pack  100  of the present example having two positive electrode terminals ( 162  and  172 ) and two negative electrode terminals ( 167  and  177 ). 
       FIG. 9  is a block diagram showing an internal circuit of the battery pack  100  of the present example. Here, only basic components for explaining a connection status of a microcontroller  154  and protection ICs  180  and  190  with respect to the upper cell unit  146  and the lower cell unit  147  are shown, and illustration of other related circuits, particularly, circuits for communicating with signal terminals on the main device side or the like is omitted. As illustrated in  FIG. 4 , the battery pack  100  is configured to include the upper positive electrode terminal (upper +)  162 , the lower positive electrode terminal (lower +)  172 , the upper negative electrode terminal (upper −)  167 , and the lower negative electrode terminal (lower +)  177 . In addition to these, the battery pack  100  includes other signal terminal groups (T terminal, V terminal, LS terminal, and LD terminal), but illustrations thereof are omitted here. An output of the upper cell unit  146  is connected to the upper positive electrode terminal  162  and the lower negative electrode terminal  177 . That is, the positive electrode (+ output) of the upper cell unit  146  is connected to the upper positive electrode terminal  162 , and the negative electrode (− output) of the upper cell unit  146  is connected to the lower negative electrode terminal  177 . Similarly, the positive electrode (+ output) of the lower cell unit  147  is connected to the lower positive electrode terminal  172 , and the negative electrode (− output) of the lower cell unit  147  is connected to the upper negative electrode terminal  167 . 
     The protection ICs  180  and  190  for monitoring voltages of the battery cells are connected to the upper cell unit  146  and the lower cell unit  147 , and the microcontroller  154  is connected to the protection ICs  180  and  190 . When a voltage between both ends of each battery cell of the upper cell unit  146  is input, the protection IC  180  executes a cell balance function, a cascade connection function, and a disconnection detection function in addition to an overcharge protection function and an over-discharge protection function, and the protection IC  180  is an integrated circuit available on the market as a “protection IC for a lithium-ion battery.” Also, when the voltage of the battery cell of the upper cell unit  146  has been dropped below a predetermined value and become an over-discharged state, the protection IC  180  outputs a signal (high signal)  183  indicating the over-discharge to the microcontroller  154 , and when the voltage of the battery cell of the upper cell unit  146  has reached a predetermined value or more at the time of charging and become an overcharged state, a signal (high signal)  184  indicating the overcharge is output to the microcontroller  154 . 
     The protection IC  190  is connected to the lower cell unit  147 . Here, the microcontroller (Micro Controller Unit)  154  is connected in the circuit of the lower cell unit  147 , that is, in the circuit between the lower positive electrode terminal  172  and the upper negative electrode terminal  167 . An output from the protection IC  180  (an over-discharge signal  183  and an overcharge signal  184 ) and an output from the protection IC  190  (an over-discharge signal  191  and an overcharge signal  192 ) are input to the microcontroller  154 . The microcontroller  154  includes, for example, a voltage detection circuit called an analog front end (AFE) to measure a current value flowing from an output voltage of a current detection circuit  193  to the lower cell unit  147 . A power supply for driving the microcontroller  154  is generated by a power supply circuit  185  connected to the lower cell unit  147 , and a power supply voltage (VDD1) is supplied to the microcontroller  154 . A shunt resistor  194  for measuring a current value is provided on the ground side of the lower cell unit  147 . 
     The microcontroller  154  monitors a current value and a cell temperature, and monitors states of the upper cell unit  146  and the lower cell unit  147  to control an operating status of the two in an integrated manner. Also, when the power tool main body  1  needs to be stopped urgently, a discharge inhibit signal is sent to the electric device main body side via the LD terminal (not shown). The protection IC  190  monitors a voltage of the battery cell in the lower cell unit  147  and sends the over-discharge signal  191  to the microcontroller  154  when a state in which the voltage has dropped to a predetermined lower limit value (over-discharge state) is detected. The microcontroller  154  includes a timer circuit and a storage device together with a microprocessor (which are not shown). The microcontroller  154  stores a battery voltage, a temperature, and a count value of the number of times of charging which have been monitored in the storage device. 
     A wireless communication circuit  155  is connected to the microcontroller  154 . An antenna  156  is connected to the wireless communication circuit  155 . Here, a wireless communication module  153  available on the market is used and mounted on the circuit board  150 . The wireless communication module  153  is one in which the wireless communication circuit  155  and the antenna  156  are collectively mounted on a common base (not illustrated). Here, the wireless communication module  153  or the antenna  156  corresponds to a wireless communication unit in the present invention. 
     When the battery pack  100  is mounted to an external charging device (not shown) and is being charged, in a case in which the protection IC  190  detects that a voltage of the battery cell exceeds a predetermined upper limit value, the protection IC  190  sends the overcharge signal  192  indicating an overcharge state to the microcontroller  154 . The microcontroller  154  stores the information in the storage device and sends a charge stop signal to the charging device (not shown) via the LS terminal (not shown). 
     The power supply circuit  185  generates a power supply for operating the microcontroller  154  using the power of the lower cell unit  147 . The power supply circuit  185  for the microcontroller  154  is provided on the lower stage side, and the microcontroller  154  is provided in the circuit of the lower cell unit  147 . Due to this disposition of the microcontroller  154 , the microcontroller  154  can be operated stably even when the output voltage is configured to be switched between the rating of 18 V and 36 V. The microcontroller  154  can switch between holding and releasing of the power supply voltage (VDD1) applied to itself and has a normal operation state (normal mode) and an operation stop state (so-called sleep mode). 
     An output of an upper voltage detection circuit  182  connected to the upper positive electrode terminal  162  is input to the microcontroller  154 . This output indicates a potential of the upper cell unit  146  when the battery pack  100  is not mounted to the power tool main body  1  or an external charging device (not shown). On the other hand, when the battery pack  100  is mounted to the power tool main body  1  for low voltage (18 V), since the upper positive electrode terminal  162  and the lower positive electrode terminal  172  are connected, the positive electrodes of the upper cell unit  146  and the lower cell unit  147  have the same potential, and the negative electrodes thereof have the same potential. From this, the microcontroller  154  can determine whether the battery pack  100  is in a state of not being mounted, is mounted to a low-voltage device main body, or is mounted to a high voltage device by comparing the potential of the upper positive electrode terminal  162  with the potential of the lower positive electrode terminal  172 . Further, in order to detect the potential of the lower positive electrode terminal  172 , it is preferable to configure the microcontroller  154  to acquire a positive electrode potential of a battery cell  147   a  at a highest level among the battery cells in the lower cell unit  147 . Although not illustrated in  FIG. 5 , in a situation in which the power supply from the battery pack  100  has to be stopped, for example, when an excessive current during discharge, a decrease in cell voltage during discharge (over-discharge), an abnormal rise in cell temperature (overtemperature), or the like occurs, an operation of the power tool main body  1  can be stopped quickly by transmitting the LD signal to the power tool main body side via the microcontroller  154 . 
       FIG. 10  is a side view of the separator  245  after the parts illustrated in  FIG. 5  are assembled, in which (A) of  FIG. 10  is a right side and (B) of  FIG. 10  is a left side view. Here, for ease of explanation, only two sets of the positive electrode terminal ( 162  and  177 ) and the negative electrode terminal ( 167  and  177 ) for discharging are illustrated as the connection terminal groups, and illustration of the other connection terminals ( 161 ,  164  to  166 ,  168 , and  171 ) is omitted. Also, a status before a resin layer on the circuit board  150  is formed is illustrated. The upper cell unit  146  is constituted by the battery cells  146   a  to  146   e  disposed on the upper stage side and is connected to the circuit board  150  by the lead-out tab  261   a  extending upward from the lead-out plate  261  on the positive electrode side and the lead-out tab  266   a  extending upward from the lead-out plate  266  on the negative electrode side. Slit-shaped through holes (not illustrated) are opened in the circuit board  150 , and the lead-out tabs  261   a  and  266   a  are caused to pass through the through holes from a lower side to an upper side so that upper portions of the lead-out tabs  261   a  and  266   a  are exposed upward from the surface of the circuit board  150 . When those portions are soldered, the circuit board  150  and the lead-out tabs  261   a  and  266   a  are electrically connected. Similarly, the lower cell unit  147  is constituted by the battery cells  147   a  to  147   e  disposed on the lower stage side and is connected to the circuit board  150  by the lead-out tabs  271   a  and  276   a  for connection extending upward from the lead-out plates  271  and  276  provided at both ends. Slit-shaped through holes (not illustrated) are opened in the circuit board  150 , and the lead-out tabs  271   a  and  276   a  are caused to pass through the through holes from a lower side to an upper side so that upper portions of the lead-out tabs  271   a  and  276   a  are exposed upward from the surface of the circuit board  150 . When those portions are soldered, the circuit board  150  and the lead-out tabs  271   a  and  276   a  are electrically connected. 
     The intermediate lead-out tab  263   a  extending upward is provided to the connection plate  263  illustrated in (A) of  FIG. 10 , and the intermediate lead-out tab  262   a  extending upward is provided to the connection plate  262  illustrated in (B) of  FIG. 10 . The intermediate lead-out  262   a  and  263   a  are bent bodies of thin metal plates that form the intermediate lead-out tabs  262   a  and  263   a  by extending plate-shaped members upward from the connection plates  262  and  263  disposed on the upper stage side, bending them inward along the circuit board  150 , and bending them upward again. Slit-shaped through holes (not illustrated) are opened in the circuit board  150 , and the intermediate lead-out tabs  262   a  and  263   a  are caused to pass through the through holes from a lower side to an upper side so that upper portions of the intermediate lead-out tabs  262   a  and  263   a  are exposed upward from the surface of the circuit board  150 . The intermediate lead-out tabs  262   a  and  263   a  are fixed to the circuit board  150  by soldering. A width (distance in a front-rear direction) of the intermediate lead-out tabs  262   a  and  263   a  is formed to be smaller than a width (length in the front-rear direction) of the lead-out tab  261   a  of (A) of  FIG. 10  and the lead-out tab  266   a  of  FIG. 10 . This is because the lead-out tabs  261   a ,  266   a ,  271   a , and  276   a  are terminals for power output and are terminals through which a high voltage and a large amount of current flow, whereas the intermediate lead-out tabs  262   a  and  263   a  are terminals which are connected for measuring an intermediate potential and through which only a small amount of current flows. An intermediate lead-out tab can also be formed on the other connection plate  264  and connection plate  265  provided on the upper stage side. However, here, from a relationship of forming a wiring pattern, it is configured such that the connection terminals  264   a  and  265   a  are provided to connect with the circuit board  150  by lead wires (not illustrated). Since it is difficult to connect the connection plates  272  to  275  provided on the lower stage side to the circuit board  150  by lead-out tabs, the connection terminals  272   a  to  275   a  are provided to connect with the circuit board  150  by lead wires  296  to  299 . 
       FIG. 11  is a perspective view illustrating a state in which the circuit board  150  is fixed to the separator  245  and illustrates a state seen from the above left front. In the circuit board  150 , the upper portions of the tabs  261   a ,  266   a ,  271   a , and  276   a  are exposed upward from the surface of the circuit board  150  from slit-shaped through holes  159   a  to  159   d . When the exposed portions of those tabs are soldered, the circuit board  150  and the lead-out tabs  261   a ,  266   a ,  271   a , and  276   a  are electrically connected. As described above, the battery cells  146   a  to  146   e  of the upper cell unit  146  are directly connected to the circuit board  150 , and the battery cells  147   a  to  147   e  of the lower cell unit  147  are directly connected to the circuit board  150 . Also, the lead wires  296  to  299  for measuring potentials of the connection plates  262  to  264  and the connection plates  272  to  274  (however,  297  and  299  cannot be seen in  FIG. 11 ) are connected. The end portions  294   b ,  296   b ,  297   b ,  298   b , and  299   b  of the lead wires illustrated in  FIG. 4  are soldered to the circuit board  150 . The connection plates  262  and  263  (see  FIG. 12 ) that are close to the circuit board  150  are bent in an L shape and vertical plate portions thereof are directly connected to the circuit board  150  using the intermediate lead-out tabs  262   a  and  263   a  extending upward. 
     The lead-out tabs  261   a  and  266   a  for output (+ output and − output) of the upper cell unit  146  are shaped to have a substantially L shape when viewed from the front or the rear and are disposed such that a longitudinal direction thereof is parallel to a long side of the substantially rectangular circuit board  150 . The lead-out tabs  261   a  and  266   a  are bent bodies of thin metal plates in which bent vertical wall portions thereof are used as the lead-out tabs  261   a  and  266   a  by causing surfaces of the lead-out plates  261  and  266  fixed to the terminals of the battery cells to be extended upward and bent inward, slightly extending them inward in a horizontal direction along the upper surface of the separator, and bending them upward in an L shape at an appropriate position. However, the same lead-out method cannot be employed for the battery cells disposed in the lower stage, because electrodes for the battery cells are positioned in the upper stage. Therefore, in the present example, the lead-out plate  271  from a terminal surface  271   b  (see also (A) of  FIG. 13 ) of the lower cell is extended forward and then bent at a right angle to the left side to form a side surface portion  271   c , and the side surface portion  271   c  is extended upward. That is, the lead-out plate  271  was extended upward along the side surface on the short side in a top view of the separator  245  and bent from the front side surface to the rear side of the separator  245  to form a horizontal surface portion  271   d , and the horizontal surface portion  271   d  was extended upward at a right angle in a tab shape to form the lead-out tab  271   a . The lead-out tab  271   a  is passed through the slit-shaped through hole  159   c  formed in the circuit board  150  from the back surface to the surface and is soldered. The lead-out tabs  271   a  and  276   a  are disposed so that a longitudinal direction thereof is parallel to a short side of the substantially rectangular shape. With the formation as described above, the lead-out plate  271  from the battery cell on the lower stage side can be disposed without interfering with the lead-out plate of the battery cell on the upper stage side. 
     The lead-out plate  276  from the negative terminal on the lower stage is also drawn out in the same manner (see  FIG. 12  described later) and is drawn out to the lead-out tab  276   a . In this way, an output from the battery cells disposed on the lower stage can be efficiently drawn out to an upper portion of the battery cells on the upper stage, that is, an upper surface portion of the separator, by drawing out the separator upward utilizing not only both the left and right lateral side surfaces but also the front side surface and the rear side surface. The lead-out plate  271  further includes a portion in which a width of the connection path is greatly reduced, that is, a fuse part  271   e . The fuse part  271   e  is a portion obtained by forming a cutout part  271   f  from a right side of the lead-out plate  271  and forming a cutout part  271   g  from a left side thereof so that a width (width in a left-right direction) of the remaining portion is sufficiently reduced, and due to the portion, a function as a power fuse is given to the lead-out plate  271 . A similar fuse function is similarly provided in the vicinity of the lead-out tab  261   a  of the lead-out plate  261  (see  FIG. 12 ) from the positive terminal of the upper cell unit  146 . The oval connection plates  262 ,  264 ,  273 , and  274  for connecting electrodes of adjacent battery cells are formed of a thin metal plate such as stainless steel and are fixed by spot welding to the battery cells. 
     The upper cell unit  146  includes the lead-out tab  261   a  for a positive output and the lead-out tab  266   a  for a negative output. Also, the lower cell unit  147  includes the lead-out tab  271   a  for a positive output and the lead-out tab  276   a  for a negative output. In the present example, installation positions of the lead-out tabs  261   a ,  266   a ,  271   a , and  276   a  are also designed. A left-right center line of the circuit board  150  or a center line between the positive electrode terminal pair ( 162  and  172 ) and the negative electrode terminal pair ( 167  and  177 ) is assumed to be a left-right center line A 1  indicated by a dotted line. Also, a line connecting two center positions including a center position between the leg parts of the upper positive electrode terminal  162  and the lower positive electrode terminal  172  and a center position between the leg parts of the upper negative electrode terminal  167  and the lower negative electrode terminal  177  is assumed to be a virtual line A 2  indicated by a dotted line. When the left-right center line A 1  and the leg part center line A 2  in a front-rear direction were drawn, the positive electrode lead-out tab  261   a  of the upper cell unit  146  was configured to be present in a region in which the leg part of the upper positive electrode terminal  162  was present, and the positive electrode lead-out plate  271   a  of the lower cell unit  147  was configured to be present in a region in which the leg part of the lower positive electrode terminal  172  was present. When the lead-out tabs  261   a  and  271   a  are disposed in this way, the lead-out tab  261   a  and the upper positive electrode terminal  162 , and the lead-out plate  271   a  and the lower positive electrode terminal  172  can be efficiently connected by a wiring pattern disposed on the circuit board  150 . Similarly, the negative electrode lead-out tab  276   a  of the lower cell unit  147  was configured to be present in a region in which the leg part of the upper negative electrode terminal  167  was present, and the negative electrode lead-out tab  266   a  of the upper cell unit  146  was configured to be present in a region in which the leg part of the lower negative electrode terminal  177  was present. When the lead-out tabs  276   a  and  266   a  are disposed in this way, the upper negative electrode terminal  167  and the lower negative electrode terminal  177  can be efficiently connected by the wiring pattern disposed on the circuit board  150 . 
       FIG. 12  is a perspective view illustrating a state in which the circuit board  150  is fixed to the separator  245  and illustrates a state seen from the above right rear. Recessed parts  150   c  and  150   d  for positioning the circuit board  150  with respect to the separator  245  are formed on left and right edges in the vicinity of the center when viewed in a front-rear direction of the circuit board  150 , and protruding parts  245   c  and  245   d  formed on the separator  245  formed on the separator  245  engage with them. Also, an abutting part  245   e  for holding a front end of the circuit board  150  is formed on the front side of the separator  245  and abuts against a front edge portion of the circuit board  150 . Further, a terminal surface  261   b  extending parallel to the electrode of the battery cell and a horizontal surface part  261   c  bent in an orthogonal direction from the terminal surface  261   b  to the upper side of the separator  245  are formed in the lead-out plate  261 , and the horizontal surface part  261   c  is upwardly extended at a right angle in a tab shape to form the lead-out tab  261   a . A fuse part  261   d  is a portion in which a width (distance in a front-rear direction) thereof is reduced by forming a cutout part  261   e  in which a part of the horizontal surface is greatly cut out from the front side. Not only the lead-out plate  261  but also the other lead-out plates  266 ,  271 , and  276 , and the connection plates  262  to  265  and  272  to  275  are formed by subjecting a thin plate such as stainless steel to press processing. Therefore, it is not necessary to add a fuse element of a separate type to the upper cell unit  146  and the lower cell unit  147 . 
       FIG. 13  is a view for explaining a method of connecting the lead-out plates  261 ,  266 ,  271 , and  276  to the positive electrode terminals ( 162  and  172 ) and the negative electrode terminals ( 167  and  177 ) in the battery pack  100 . (A) is a view from the front side, and (B) is a view from the rear side. Of the connection terminal groups, illustration of connection terminals other than the positive electrode terminals ( 162  and  172 ) and the negative electrode terminals ( 167  and  177 ) for discharge is omitted. The lead-out tab  261   a , which is the + output of the upper cell unit  146 , is connected to the circuit board  150  by a region circle  2  on a rear side of the upper positive electrode terminal  162 . As indicated by the dotted line, the lead-out tab  261   a  and the upper positive electrode terminal  162  can be connected at a short distance in a linear manner. The lead-out tab  266   a , which is the − output of the upper cell unit  146 , is connected to the circuit board  150  by a region circle  3  on a front side of the lower negative electrode terminal  177 . As indicated by the dotted line, the lead-out tab  266   a  and the lower negative electrode terminal  177  can be connected at a short distance in a linear manner. The lead-out tab  271   a , which is the + output of the lower cell unit  147 , is connected to the circuit board  150  by a region circle  1  on a front side of the lower positive electrode terminal  172 . Therefore, as indicated by the dotted line, the lead-out tab  271   a  and the lower positive electrode terminal  172  can be connected at a short distance in a linear manner. The lead-out tab  276   a , which is the − output of the lower cell unit  147 , is connected to the circuit board  150  by a region circle  4  on a rear side of the upper negative electrode terminal  167 . Therefore, as indicated by the dotted line, the lead-out tab  276   a  and the upper negative electrode terminal  167  can be connected at a short distance in a linear manner. As described above, since the wirings for power can be linearly connected to the connection terminals ( 162 ,  167 ,  172 , and  177 ) like the four dotted lines illustrated on the circuit board  150 , the wiring pattern thereof can be efficiently disposed on the circuit board as a thick wiring pattern without intersecting each other. 
     As described above, in the battery pack  100  of the present example, connections from the battery cells to the output terminal groups of the positive electrode terminals ( 162  and  172 ) and the negative electrode terminals ( 167  and  177 ) are realized by the wiring pattern on the circuit board  150 . Therefore, it is preferable to install a wireless communication circuit or a wireless antenna at a position away from the wiring pattern. Then, there are only two candidates for rear of installation positions, one is a position in the vicinity of the left-right center near the front short side of the rectangular circuit board  150  in a top view and, the other is a position near a left-right center in the vicinity of the rear short side of the circuit board  150 . However, in the present example, since four LEDs for checking a battery voltage are provided near a left-right center in the vicinity of the rear side indicated by the dotted line  152 , and a switch  290  for a voltage check button is provided next to them, it is difficult to mount the wireless communication circuit there. Therefore, in the present example, it was configured to mount the wireless communication circuit and the antenna unit at the position indicated by the dotted line  152 . By mounting at this position, it was possible to mount the wireless communication circuit at a position as far as possible from the connection terminal groups having a large number of metal portions on the back surface of the circuit board  150  and in an area as far as possible from main power lines (wiring for power). 
       FIG. 14  is a top view of the circuit board  150  of the battery pack  100  according to the present invention. Here, the wireless communication module  153  is disposed in a quadrangular region in a top view. The wireless communication module  153  is one in which the antenna  156  is formed on a resin base by a wiring pattern, in which the microcontroller  154  is provided at one end portion of the antenna  156 , and a capacitor  157  is provided at the other end portion of the antenna  156 . The capacitor  157  is provided at a distal end of the antenna  156  and is also used to solder the antenna  156  to the wiring pattern of the circuit board  150 . The microcontroller  154  is a general-purpose microcontroller in which a Bluetooth (registered trademark) communication circuit is incorporated, and here, the microcontroller  154  performs control of consolidating information from the protection ICs  180  and  190  and transmitting the LD signal and the LS signal to an electric device main body to be mounted and the charger by being connected to the protection ICs  180  and  190  for charge/discharge control of the battery, monitors a status of the upper cell unit  146  and the lower cell unit  147 , and periodically stores a state of the battery cells in a storage device (nonvolatile memory) (not illustrated). Further, the microcontroller  154  enables communication by Bluetooth (registered trademark) in response to a pairing request from the outside, and here, performs communication with the external terminal device  301  (see  FIG. 1 ). 
     On the circuit board  150  of the present example, the metal terminals  261   a ,  266   a ,  271   a , and  276   a  of the positive electrodes and the negative electrodes in which a large amount of current due to 18 V DC or 36 V DC flows are diagonally disposed. Also, as illustrated in  FIG. 13 , wirings from the metal terminals  261   a ,  266   a ,  271   a , and  276   a  to the connection terminal group  160  are performed by a circuit pattern formed on the circuit board  150  (further, wirings of these using lead wires may also be used). As described above, there is a portion in which a high current at a high voltage flows in the vicinity of the wireless communication module  153 , and furthermore, presence of large metal terminals hinders wireless communication. Therefore, in the present example, in order to reduce these effects and improve a radiation efficiency from the antenna  156 , the wireless communication module  153  was disposed substantially at a center of a front side edge portion of the circuit board  150  with a mounting direction of the battery pack  100  as a reference. Moreover, the antenna  156  was positioned on a front side of the microcontroller  154  so that it was disposed to be as far away from the connection terminal group  160  as possible. With this disposition, since peripheries of the antenna  156 , particularly the front side, the upper side, and the lower side, are not necessary to be covered by a metal portion radio waves are satisfactorily radiated from the antenna  156 . 
     When it is assumed that the wireless communication module  153  is disposed in the vicinity of the center of the circuit board  150 , for example, near the position indicated by an arrow  150   b , there are metal connection terminals on the front side, metal terminals (the intermediate lead-out tabs  262   a  and  263   a , and the lead-out tabs  261   a  and  276   a ) extending from the battery cells on the right and left sides, and protection ICs  180  and  190  and the like on the rear, and thereby the peripheries are surrounded by metal parts. Moreover, when an electric device to be mounted is an impact tool as illustrated in  FIG. 3 , a control circuit board (not illustrated) on the power tool main body side is mounted on an upper side of the arrow  150   b , and this is not preferable as a radiation environment for radio waves. 
     It is also conceivable that the wireless communication module  153  is disposed near a left-right center at a rear edge portion of the circuit board  150 . However, the switch unit for voltage check (see  290  in  FIG. 13 ) and five LEDs  158  are mounted in the vicinity of the mounting hole  151   b  on the rear. Therefore, the wireless communication module  153  cannot be mounted at that position. In the present example, in comprehensive consideration of the above viewpoints, when a front region of the connection terminal group  160  of the circuit board  150  was divided into three equal sections in a left-right direction, the connection tabs from the battery cells were disposed in the regions on both left and right sides, and the wireless communication module  153  was mounted in the central region. 
       FIG. 15  is a top view illustrating a state in which the module of wireless communication is removed in the circuit board  150  of  FIG. 14 . A difference from  FIG. 14  is that a soldering pad (land) group  195  formed on the circuit board  150  is illustrated with the wireless communication module  153  portion removed. Although not illustrated here, a rear view of the wireless communication module  153  also has a shape corresponding to the connection pad group  195 , and these are soldered by a reflow process. 
       FIG. 16  is a cross-sectional view along line A-A of the circuit board  150  of  FIG. 14 . Here, only a size of the wireless communication module  153  and the protection IC  190  are illustrated, and illustration of metal terminals and mounted elements other than those is omitted. The microcontroller  154  is covered with a metal cover, and the wiring of the antenna  156  is sufficiently small compared to the cover. Therefore, when radiation of the radio waves from the antenna  156  is considered, it is better to position the antenna  156  on a front side of the microcontroller  154 . Also, a control circuit of the battery cell including the protection IC  190  is disposed behind the connection terminal group  160 . 
       FIG. 17  is a front view of the circuit board  150  of the battery pack  100  of  FIG. 14 . This figure also illustrates only the size of the wireless communication module  153  (the microcontroller  154 , the antenna  156 , and the capacitor  157 ) and the protection IC  180 . From this figure, it can be understood that the antenna  156  is disposed to be in close contact with the circuit board  150 . 
       FIG. 18  is a view illustrating a status of silicone application on the circuit board  150  of the battery pack  100  according to the present invention. When all the electronic elements mounted on the circuit board  150  are soldered, and furthermore, soldering to the connection terminal groups is completed, a silicone resin layer is formed on almost all of the upper surface of the circuit board  150  for dustproofing and waterproofing purposes. Although formation of the silicone resin layer can be considered in various ways, for example, it can be formed by application. At this time, when silicone is applied to all the portion in which the antenna and the microcontroller are integrated into one module for dustproofing and waterproofing purposes, since the silicone resin layer is also formed on the antenna, the silicone itself may be a shield for radiation of radio waves. Therefore, in the present example, application of the silicone resin onto the antenna unit was avoided as far as possible. However, in a mass production process, demanding detailed restrictions on silicone application can be a factor that greatly reduces a production efficiency, and at the same time, may increase a rate of defects and increase individual differences in the performance of finished products. Therefore, in the present example, a waterproof wall is formed by a rubber frame body  281  so that the silicone resin is not applied to an inner portion of the frame body  281  serving as the waterproof wall. The frame body  281  is integrally formed with rubber and is positioned to be fitted into an outer frame portion of the microcontroller  154 . In a state in which the upper case  110  and the lower case  101  of the battery pack  100  are integrated, it is configured such that an upper surface of the frame body  281  is in contact with a surface of the upper case  110  on the cell unit side and there is no gap between the frame body  281  and the upper case  110 . Thereby, water and dust do not enter the antenna unit even without applying the silicone resin on the antenna unit. The frame body  281  corresponds to an inhibiting part and a sealing member in the present invention. 
     The silicone resin is applied on the entire upper surface of the circuit board  150  as illustrated by hatching with wavy lines. In the connection terminal group  160 , the resin is applied only around the leg parts to be soldered. On the rear side of the connection terminal group  160 , the resin is applied to all portions except for both left and right sides  285   a  and  285   b  on which the resin does not need to be applied. Although not visible in  FIG. 18 , almost the entire back surface of the circuit board  150  is preferably covered with a silicone resin. 
       FIG. 19  is a perspective view of the frame body  281  of  FIG. 18 . The frame body  281  is manufactured by integrally forming rubber and is fitted into the antenna unit (the antenna wire  156  and the capacitor  157 ) and the outer frame portion of the microcontroller  154 . Instead of bringing the frame body  281  into contact with the upper case  110  of the battery pack  100 , a rubber sheet  282  may be further provided on an upper side of the frame body  281 . Thereby, water and dust do not enter the antenna unit even without applying the silicone resin to the antenna unit. The rubber sheet  282  may be fixed to the upper surface of the frame body  281  by adhesion. 
       FIG. 20  is a view illustrating a status of silicone application on the circuit board  150  by a method different from that of  FIG. 18 . Here, instead of limiting longitudinal and lateral directions of the microcontroller  154  by the frame body  281 , a sheet-shaped rubber  283  was used to cover not only the front, rear, left, and right of the microcontroller  154  but also the upper surface. However, when the antenna  156  is also covered, there is a likelihood that a radiation efficiency of radio waves may be lowered, and thus a recessed notch  283   a  was provided on a front edge portion of the rubber sheet  283  only around the antenna  156 . At this time, a waterproofing property is ensured by attaching an edge portion of the notch  283   a  to be in close contact with a side surface of a shield covering the microcontroller  154 . Although the silicone resin is applied around the rubber sheet  283 , particularly on the right side, left side, and rear side, when it is difficult for the silicone resin to be applied to border an outer edge of the rubber sheet  283  without gaps, the resin is also applied on the rubber sheet  283  so that the resin adheres to an upper side of the outer edge portion  283   b  as illustrated in  FIG. 20 . 
     According to the examples illustrated in  FIGS. 18 to 20 , since the resin layer was formed by covering almost all the circuit board  150  other than the wireless communication module  153  with silicone, waterproofing and dustproofing properties of the electronic elements mounted on the circuit board  150  could be significantly improved. Also, regarding the wireless communication module  153 , particularly the antenna unit was not covered with the resin, and thereby a likelihood of deterioration in radiation performance of radio waves could be eliminated. Further, a material of the resin layer is not limited to silicone, and other resins having excellent workability, a waterproofing property, and a dustproofing property may also be used. 
       FIG. 21  is a partial enlarged view illustrating a configuration in which the frame body  281  is sealed by the upper case  110 . A rib  116  extending in a battery cell direction is provided on a surface of the upper case  110  of the battery pack  100  facing the battery cells. The rib  116  has a contact surface that comes into contact with the frame body  281  and is configured so that the entire circumference of the contact surface is in contact with the frame body  281  in an assembled state of the battery pack  100 . Thereby, in the assembled state of the battery pack  100 , the circuit board  150 , the frame body  281 , the rib  116 , and the upper case  110  can seal the communication module  153 , and thereby a likelihood of deterioration in radiation performance of radio waves can be suppressed and waterproofing and dustproofing properties can be improved. 
     Although the present invention has been described above on the basis of examples, the present invention is not limited to the above-described examples, and various modifications can be made in a range not departing from the meaning of the present invention. For example, in the above-described example, Bluetooth (registered trademark) is mounted on the voltage variable battery pack, but the wireless communication device may be mounted not only on the voltage variable battery pack but also on the voltage-fixed battery pack using the present invention. 
     REFERENCE SIGNS LIST 
     
         
         
           
               1  Power tool main body 
               2  Housing 
               2   a  Body portion 
               2   b  Handle part 
               2   c  Battery pack mounting part 
               3  Motor 
               4  Trigger switch 
               5  Forward/reverse switch lever 
               8  Distal end tool holding part 
               9  Distal end tool 
               10  Battery pack mounting part 
               11   a ,  11   b  Rail groove 
               12  Curved part 
               14  Protruding part 
               20  Terminal part 
               20   a  Vertical surface 
               20   b  Horizontal surface 
               22  Positive electrode input terminal 
               27  Negative electrode input terminal 
               50  Terminal part 
               51  Base 
               51   a ,  51   b  Recessed part 
               52  Positive electrode input terminal 
               52   c  Wiring part 
               54   c  Wiring part 
               57  Negative electrode input terminal 
               59  Short circuit 
               59   a ,  59   b  Short-circuit terminal 
               60  Microcontroller 
               61  Power supply device 
               70  Load device 
               80  Terminal part 
               81  Base 
               82  Positive electrode input terminal 
               84  to  86  Signal terminal 
               87  Negative electrode input terminal 
               88  Signal terminal 
               100  Battery pack 
               101  Lower case 
               104  Slit 
               110  Upper case 
               111  Lower stage surface 
               111   a  Notch part 
               115  Upper stage surface 
               116  Rib part 
               121  to  128  Slot 
               131  Stopper part 
               132  Raised part 
               134  Slit 
               138   a ,  138   b  Rail 
               141  Latch 
               142  Locking part 
               146  Upper cell unit (first cell unit) 
               145   a  to  145   e  Battery cell 
               147  Lower cell unit (second cell unit) 
               147   a  to  147   e  Battery cell 
               150  Circuit board 
               150   b  Arrow 
               150   c  Recessed part 
               151   a ,  151   b  Mounting hole (of circuit board) 
               152  Mounting region (of wireless communication device) 
               153  Wireless communication module 
               154  Microcontroller 
               155  Wireless communication circuit 
               156  Antenna 
               157  Capacitor 
               158  LED 
               159   a  to  159   d  Through hole 
               160  Connection terminal group 
               161 ,  162  Upper positive electrode terminal 
               162   a ,  162   b  Arm part 
               164  T terminal 
               165  V terminal 
               166  LS terminal 
               167  Upper negative electrode terminal 
               167   a ,  167   b  Arm part 
               168  LD terminal 
               171 ,  172  Lower positive electrode terminal 
               172   a ,  172   b  Arm part 
               177  Lower negative electrode terminal 
               177   a ,  177   b  Arm part 
               180  Protection IC 
               182  Upper voltage detection circuit 
               183  Over-discharge signal 
               184  Overcharge signal 
               185  Power supply circuit 
               190  Protection IC 
               191  Over-discharge signal 
               192  Overcharge signal 
               193  Current detection circuit 
               194  Shunt resistor 
               195  Pad group 
               245  Separator 
               245   c  Protruding part 
               245   e  Abutting part 
               246  Space 
               247   a  Screw boss 
               250  Tab holder 
               261  Lead-out plate 
               261   a  Lead-out tab 
               261   b  Terminal surface 
               261   c  Horizontal surface part 
               261   d  Fuse part 
               261   e  Cutout part 
               262 ,  263 ,  264 ,  265  Connection plate 
               262   a ,  263   a  Tab 
               264   a  Connection terminal 
               266  Lead-out plate 
               266   a  Tab 
               271  Lead-out plate 
               271   a  Lead-out tab 
               271   b  Terminal surface 
               271   c  Side surface portion 
               271   d  Horizontal surface part 
               271   e  Fuse part 
               271   f  Cutout part 
               272  Connection plate 
               272   a  Connection terminal 
               276  Lead-out plate 
               276   a  Lead-out tab 
               278   a ,  278   b  Insulating sheet 
               281  Frame body 
               282  Rubber sheet 
               283  Rubber sheet 
               283   a  Notch 
               283   b  Outer edge portion 
               285   a ,  285   b  Both sides (of circuit board) 
               290  Switch 
               294   b  End portion (of lead wire) 
               296  to  299  Lead wire 
               296   b ,  297   b ,  298   b ,  299   b  End portion (of lead wire) 
               296  Lead wire 
               300  Support company 
               301  Terminal device 
               302  Display screen 
               350  Network 
               360  Base station 
               361  Telephone communication network