Patent Publication Number: US-2005134217-A1

Title: Charger for mobile telephone

Description:
TECHNICAL FIELD  
      The present invention relates to a charger for mobile phone, and more specifically to a charger for mobile phone capable of charging all mobile phones or batteries regardless of manufacturers and models thereof.  
     BACKGROUND ART  
      Nowadays, the market of the personal mobile communication area is being expanded and thus competition in the area of the mobile phone is heightening more and more. Accordingly, the number of manufactures manufacturing a mobile phone is increasing. The manufacturers put on the market more miniaturized and diversified products in order to improve functionality of terminals and correspond to users&#39; tastes.  
      Therefore, as the model of the mobile phone is diversified, the shape and the structure of a charger for charging it should be diversified and thus the manufacturers should supply a charger peculiar to each new model, so that the manufacturing cost is increased. Further, the user suffers from inconvenience that his own charger has to be carried in his travel or long business trip. Furthermore, when new terminals are purchased, the resource loss and the environmental pollution due to chargers to be disused become more serious.  
      Accordingly, in this area, development of a general purpose charger capable of charging all types of mobile phones or batteries regardless of models of the mobile terminal has been required.  
       FIG. 1  shows a charger  10  for vending machine that is currently used in convenience stores. In order to use this charger, a user should find out a connector  11  corresponding to the manufacturer and model of his mobile phone and connect it to his terminal  12 .  
      At present, the charger shown in  FIG. 1  provides much convenience for users, but this apparatus has inconvenience in that the user should find out a connector corresponding to the manufacturer and model of his mobile phone and then connect it to his terminal. Further, since the apparatus cannot charge the terminal without the connector corresponding to its model, every time a new model is put on the market, a connector corresponding to the new model should be provided for service. Furthermore, since the apparatus has to include connectors corresponding to models of all manufacturers that have ever been put on the market, its volume should be great. Accordingly, the conventional apparatus has a problem that it is not efficient for space or production cost.  
      Therefore, in order to solve the above problems, an object of the present invention is to provide as a general purpose charger a charger for mobile phone capable of automatically identifying various types of batteries and charging them.  
      Another object of the present invention is to provide a general purpose charger having a small volume, which can be used for the domestic purpose as well as for the public purpose.  
     DISCLOUSRE OF INVENTION  
      In order to accomplish the above objects, the present invention provides a charger for mobile phone, comprising: a housing  20 ; a battery mounting unit  21  for allowing a battery  30  of the mobile phone to be mounted into the housing  20 ; a battery fixing unit  22  provided in the battery mounting unit  21 , for locating the battery  30  at the center of the battery mounting unit  21 ; a battery sensing unit  73  provided in the battery mounting unit  21 , for sensing that the battery  30  is mounted on the battery mounting unit  21 ; two charging terminal units  25 ,  26  in horizontal and vertical directions including a plurality of terminals  48 ,  38  coming in contact with metal terminals  31 ,  32  of the battery  30  so as to obtain a battery charging information; limit switch units  37 ,  47  provided in the two charging terminal units  25 ,  26 , for adjusting movement of the battery mounting unit in accordance with a size of the battery  30  to be mounted on the battery mounting unit so as to accurately bring the charging terminal units  25 ,  26  into contact with the metal terminals  31 ,  32  of the battery; a control unit  28  connected to the charging terminal units, for controlling contact of the metal terminals  31 ,  32  of the battery with the charging terminal units  25 ,  26  and searching a charging information; and a charging circuit unit  27  connected to the control unit  28 , for supplying the charging terminal units  25 ,  26  with a voltage using the charging information searched by the control unit  28  to charge the battery  30 .  
      In the present invention, the control unit  28  first brings the horizontal charging terminal unit  26  of the two charging terminal units into contact with the battery to search the charging information, and when the charging information is not obtained, the control unit  28  separates the horizontal charging terminal unit  26  from the battery and then, in turn, brings the vertical charging terminal unit  25  of the two charging terminal units into contact with the battery to search the charging information.  
      Also, in the present invention, the charging terminal units include a terminal portion and a terminal protecting portion, and the terminals have a pin shape. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
      The above and other objects, advantages and features of the present invention will become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which:  
       FIG. 1  is a simplified perspective view of a conventional charger using a connector;  
       FIG. 2  is a perspective view of a charger for mobile phone according to the present invention;  
       FIG. 3   a  and  FIG. 3   b  are views illustrating a general structure of battery, respectively;  
       FIG. 4   a  and  FIG. 4   b  are views illustrating a state that the charging terminal unit and the metal terminals of battery are in contact with each other in the charger according to the present invention, respectively;  
       FIG. 5  is a view illustrating a structure of an individual terminal of the charging terminal unit according to the present invention;  
       FIG. 6  is a view illustrating a structure of the charging terminal unit according to the present invention;  
       FIG. 7  is a plan view illustrating a structure of the battery mounting unit according to the present invention;  
       FIG. 8  is a flowchart explaining a procedure in which the battery is mounted in the charger for mobile phone according to the present invention; and  
       FIG. 9  is a circuit diagram of the charging circuit according to the present invention. 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION  
      Now, preferred embodiments according to the present invention will be described in detail with reference to the appended drawings.  
       FIG. 2  is a perspective view of a charger according to the present invention and shows a state that a battery mounting unit is opened. As shown in  FIG. 2 , this charger comprises the battery mounting unit  21 , a battery fixing unit  22 , two charging terminal units  25 ,  26 , a control unit  28  and a housing  20  for receiving them.  
      Preferably, the control unit  28  comprises a micro chip, and is connected to the two charging terminal units  25 ,  26  to control contact of the charging terminal units with the metal terminals of the battery and to search information required for the charging.  
       FIG. 7  is a detailed view of the battery mounting unit  21 . As shown in the drawing, the battery mounting unit  21  comprises a front portion  74 , a battery carrying portion  78  and a connecting portion  76 , and the connecting portion  76  has a built-in elastic body to adjust movement of the battery carrying portion  78  correspondingly to a size of the battery to be mounted. The battery fixing unit  22  is provided on both sides of the battery mounting unit  21 , and has an elastic characteristic to serve for fixing the battery at the center of the battery mounting unit  21 .  
      A battery sensing unit  73  positioned in the battery carrying unit  78  of the battery mounting unit  21  senses that the battery is mounted. When the battery sensing unit  73  becomes on, that is, when the battery is mounted, the control unit  28  starts operations required for charging the battery. However, if the battery mounting unit  21  is opened and the signal value of the battery sensing unit  73  is not varied, the battery mounting unit  21  is closed into the charger and other charging operations are not started.  
       FIG. 3  shows two types of metal terminals of a general battery  30 . As shown in  FIG. 4 , the charging terminal units  25 ,  26  have a plurality of terminals  38 ,  48  for coming in contact with the metal terminals of the battery  30  correspondingly to their types, and preferably in the present invention, include a horizontal charging terminal unit  26  and a vertical charging terminal unit  25 .  
      By bring the plurality of charging terminals  38 ,  48  of the charging terminal units  25 ,  26  into contact with the corresponding metal terminals  31 ,  32  of the battery, the information for charging the battery can be obtained.  
      Referring to  FIG. 4  again,  FIG. 4   b  shows a state the horizontal charging terminal unit  26  is in contact with the terminal  32  of the battery  30 . The horizontal charging terminal unit  26 , as shown in  FIG. 6  in detail, comprises a terminal fixing portion  36  for fixing the plurality of terminals  38  with a pin shape and a terminal protecting portion  35 . The terminal fixing portion  36  is provided with a limit switch  37  for controlling movement of the battery carrying portion  78  correspondingly to the size of the battery  30  to be mounted on the battery mounting unit  21 . The terminal protecting portion  35  performs a function of protecting safely the pin-shaped terminals  38  to prevent bending of the pins. It is preferable that each pitch of the plurality of terminals  38  is smaller than minimum width of the metal terminals of the battery to be mounted. If each pitch of the terminals  38  is greater than the minimum width of the metal terminals of the battery, any metal terminal of the battery may not come in contact with the terminals of the charging terminal units and as a result, the control unit  28  may not search the accurate charging information for the battery.  
      As shown in  FIG. 4 , the limit switch  37  senses the size of the battery to be mounted and controls positions for contact of the charging terminals unit  26  and the battery  30 .  
       FIG. 4   a  shows a state that the vertical charging terminal unit  25  is in contact with the terminals  31  of the battery  30  and the basic construction thereof is the same as that of  FIG. 4   b.    
      The control unit  28  first brings the horizontal charging terminal unit  26  of the two charging terminal units  25 ,  26  into contact with the battery to search the charging information. When the charging information is not searched, the control unit  28  separates the horizontal charging unit  26  from the battery and then brings the vertical charging terminal unit  25  of the two charging terminal units  25 ,  26  into contact with the battery again to obtain the information required for the charging. Also, the control unit may first bring the vertical charging terminal unit  25  into contact with the battery to search the charging information. Then, when the charging information is not searched, the control unit may separate the vertical charging terminal unit  25  from the battery and then bring the horizontal charging terminal unit  26  of the two charging terminal units  25 ,  26  into contact with the battery again to obtain the information required for the charging.  
       FIG. 5  shows a single terminal of the charging terminal units. In order to lighten the impact in coming in contact with the metal terminals of the battery, the individual charging terminal  38  has an elastic member  52  built in, and in order to not only prevent the end portion of the charging terminal from being broken but also prevent the surface of the mounted battery from being damaged in coming in contact with the metal terminals of the battery, the end portion  51  of the charging terminal is rounded into a streamline shape. Furthermore, in order to improve a chance of success in contact with the metal terminals of the battery, it is preferable that the diameter of the end portion  51  of the charging terminal is minimized, and in the present embodiment, the diameter of the end portion  51  of the terminal is 1 mm or less.  
       FIG. 9  shows a charging circuit  27  operable in conjunction with the control unit  28  of the charger for mobile phone according to the present invention and control procedures till charging the battery with the required voltage with respect to the voltage input into the charger of the present invention will be described with reference to the drawing.  
      First, from construction of the charging circuit  27  of the present invention, it can be seen that a rectifier circuit (not shown) for receiving external AC voltage and rectifying it into DC voltage of 12V to output it is basically provided in the charging circuit. Further, the charging circuit  27  of the present invention comprises an input terminal  97  for receiving the voltage of 12V output from the rectifier circuit and a resistor  96  through which the voltage input to the input terminal  97  passes.  
      Furthermore, the charging circuit of the present invention comprises a comparator  96  for comparing the voltage having passed through the resistor  96  with a voltage supplied from a digital-to-analog converter  92  and a transistor  94  for adjusting the output current supplied through the resistor  96  on the basis of the comparison output of the comparator  95 . Accordingly, the transistor  94  controls amount of current flowing into the emitter terminal in accordance with the output value of the comparator  95 .  
      Furthermore, the digital-to-analog converter  92  receives as a digital signal the signal supplied from the control unit  28  altogether controlling the charging circuit of the present invention and converts it into analog signal to output it. That is, in the charging circuit of the present invention, the digital-to-analog converter  92  receives the voltage signal supplied from the control unit  28  as a digital signal and converts it into analog signal to supply it to an inverted terminal ( 1 ) of the comparator  95 . Therefore, the comparator  95  compares the voltage input to the input terminal  97  with a reference voltage that is the voltage supplied from the digital-to-analog converter  92  and then outputs a differential signal thereof.  
      Next, the control unit  28  determines amount of voltage required for the battery presently mounted in the charger by use of the terminals  38 ,  48  of the charging terminal units, supplies the determination signal to the digital-to-analog converter  92  through a bit line and receives a overload signal supplied from a analog-to-digital converter  93  to adjust the amount of voltage to be supplied to the digital-to-analog converter  92 . Further, the control unit  28  identifies an anode and a cathode of the battery mounted in the charger by use of the charging terminals  38 ,  48 , and allows the charging voltage to be supplied through the corresponding terminal of the charging terminals.  
      The analog-to-digital converter  93  detects amount of current to be output from the transistor  94  to monitor generation of overload, and serves for informing the control unit  28  of the generation of overload in the current supplied from the transistor  94 .  
       FIG. 8  is a flowchart illustrating the charging operations of the charger according to the present invention.  
      When a user clicks a charging switch  29 , the charger according to the present invention determines whether the charging circuit  27  is being operated. If the charging circuit  27  is being operated, the charging operation is stopped, the terminals of the horizontal or vertical charging terminal unit  25 ,  26  is separated from the batter  30 , and then the battery mounting unit  21  is opened. This operation can prevent damages to the charging terminal unit, which can be caused when the battery mounting unit  21  is opened directly without separation of the terminals of the charging terminal unit from the battery during operation of the charging circuit  27 . Since when the charging circuit is not under operation, the charging terminal unit is separated from the battery, the battery mounting unit  21  is directly opened. If the battery mounting unit is opened, the battery is mounted. at that time, the battery is mounted at the center of the battery mounting unit  21  by means of the battery fixing unit  22  positioned on the battery mounting unit  21 . When the battery is mounted on the battery mounting unit  21 , the limit switches  37 ,  47  control the movement of the battery carrying portion in accordance with the size of the mounted battery to bring the battery into contact with the horizontal charging terminal unit. The contact of the metal terminals of the battery with the charging terminal unit may be manually executed. The control unit  28  of the charger searches information required for charging the battery by use of the terminals of the charging terminal unit in contact with the battery. Here, in order to accurately confirm positions of the metal terminal and the other materials of the battery, an optical sensor (not shown) may be employed. At the step of searching the charging information, when the charging information, that is, information relating to the anode, the cathode and the charging voltage of the battery is searched, the charging is started through the charging circuit  27 . However, when no charging information is searched from the contacted terminals, the horizontal charging terminal unit should be separated from the battery and then be adjusted again correspondingly to the size of the battery to come in contact with the battery. The charging information is searched again by use of the contacted terminals. When the charging information is searched, the charging is started. Even in this case, when the charging information is not searched, the horizontal charging terminal unit is separated from the battery, the alarm for re-mounting is given, the battery mounting unit is opened to take out the battery, the battery is re-mounted and then the aforementioned steps should be repeated. When the charging of the battery is started, the control unit monitors whether the charging is completed, and when the charging has been completed, allows the contacted battery terminals to be separated from the battery and allows the charging completion to be displayed. Thereafter, when the charging switch is clicked, the battery mounting unit is opened to obtain the charged battery.  
      It is preferable that a user can see the charging state through a light emitting element (not shown) when the charger is charging or discharging.  
      At that time, when the charger according to the present invention is employed for the commercial purpose, operation of the charging switch  29  may be restricted by use of a locking unit (not shown). This is for the purpose of preventing persons other than the owner of the battery from taking the charged battery without permission.  
      As described above, the charger according to the present invention can charge all mobile phones and batteries regardless of manufacturers and models thereof.  
      Further, the present invention can facilitate contact of the charging terminal units with the battery, since the elastic portion is built in the battery mounting unit to be adjusted in accordance with sizes of various batteries.  
      Furthermore, it is possible to secure contact of the charging terminal unit with the battery by providing the elastic portion within the pin-shaped terminal, and it is also possible to prevent the pin-shaped terminal from getting bent or curved by use of the terminal protecting portion of the charging terminal unit.  
      Furthermore, since the plurality of charging terminals in contact with the battery are connected to the micro chip to search information required for the charging, it is possible to minimize production cost, volume and error of the charger, and since when the error occurs, inspection of the single micro chip enables the error to be detected, it is very efficient.  
      Furthermore, since the horizontal charging terminal and the vertical charging terminal come in contact with the battery at different times, accuracy, efficiency and stability in searching can be obtained.  
      The embodiments described above are not for limiting the range of the present invention, and the present invention may further comprise modifications that can be made by the skilled in the art.  
     INDUSTRIAL APPLICABILITY  
      The present invention provides a charger for mobile phone, and more specifically a charger for mobile phone capable of charging all mobile phones or batteries regardless of manufacturers and models thereof.