Abstract:
A method of breaking an overcurrent is provided to connect an overcurrent breaking controller in series between an AC power and a load. Thus, when detecting the connected load of which the current generated with the consumed power is higher than a rated current of the overcurrent breaking controller, the overcurrent breaking controller instantly stops the load working, when detecting the current passing through the load that is lower than the rated current, the controller allowing the load to re-work. Thus, the load of which the rated current exceeds is prevented from being replaced, and automatic power shut and recovery are implemented for protection, power saving, easy installation, and energy waste prevention.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates to a method that forces electricity economy and particularly to a method of breaking an overcurrent for economizing on energy of a lamp and lantern. 
         [0003]    2. Description of Related Art 
         [0004]    At the age of energy shortage and green house effect on Earth, in order to economize source of energy and protect environments on Earth, advanced countries&#39; governments has publicly proclaimed to force the use of an energy saving lamp bulb for a lamp and lantern as an illuminator; further in order to economize in electricity, the governments stipulate for the use of each of the lamp and lantern that must be provided with an overcurrent breaking controller sensing a current fed to the lamp and lantern; USA stipulate for the use of energy saving lamp and lantern starting from year 2009. 
         [0005]    With reference to  FIG. 1 , in a conventional method of breaking the overcurrent, a No-Fuse Breaker (NFB)  1  is connected in series in a circuit. One terminal of the NFB  1  is coupled to an AC power  2 , while the other terminal is coupled to a lamp and lantern  3 . A switch  4  is connected in series between the lamp and lantern  3  and the AC power  2 . When the switch  4  turns ON, the lamp and lantern  3  becomes bright. When the lamp and lantern  3  becomes bright and a current generated from its power consumption exceeds a rated current, the NFB  1  is excessively heated and mechanically interrupts the supplied power  2  for protection; namely, the rated current of NFB  1  is 1.5 Ampere. When the lamp and lantern  3  becomes bright, the 2 A current is generated that is more than the current of NFB  1  that is rated to 1.5 A. At this time, a trip occurs inside the NFB  1  because being heated, and disconnection of the lamp and lantern  3  from the AC power  2  is made, thereby the circuit of lamp and lantern  3  stays open. 
         [0006]    Consequently, because of the technical defects of described above, the applicant keeps on carving unflaggingly through wholehearted experience and research to develop the present invention, which can effectively improve the defects described above. 
       SUMMARY OF THE INVENTION 
       [0007]    In a conventional method of breaking an overcurrent, a lamp and lantern  3  is connected in series to a NFB  1 ; thus, when the lamp and lantern  3  operates, a current generated with a consumed power caused by the lamp and lantern  3  passes through the NFB  1  to make the NFB  1  to be heated and mechanically interrupted, thereby a circuit of the lamp and lantern  3  being open; however, the NFB  1  connected in the method cannot recover and the NFB  1  must be manually again recovered and is inconveniently used for operation. 
         [0008]    In this invention, a method of breaking an overcurrent is provided to connect an overcurrent breaking controller in series between an AC power and a load, in which overcurrent breaking controller mainly comprises a trigger control unit made up with a DIAC and a TRIAC, a current transformer, and an overcurrent restraint unit made up with a silicon-controlled rectifier (SCR) and a bridge rectifier. One terminal of the trigger control unit is connected to the AC power, while the other terminal is connected to the current transformer and then the load. The overcurrent restraint unit is connected between the trigger control unit and the current transformer. Thus, when the trigger control unit triggers the load to work, the load starts to consume a power and generates a current in a loop. When detecting the connected load of which the current generated with the consumed power is higher than a rated current of the overcurrent breaking controller, the overcurrent breaking controller instantly stops the load working. When detecting the current passing through the load that is lower than the rated current, the controller allows the work re-work. Thus, the method of breaking the overcurrent may not only prevent a user of ignorance from replacing the a load of which the rated current or power exceeds but also automatically turn off or connect the power supply for protection. Further, No extra power supply does not need to be connected to the controller, thereby power saving and easy installation being achieved and even energy waste being prevented. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a circuit diagram illustrating a conventional method of breaking an overcurrent; 
           [0010]      FIG. 2  is a flow chart of a method of breaking an overcurrent according to this invention; 
           [0011]      FIG. 3  is a circuit block diagram illustrating the method of breaking the overcurrent in a preferred embodiment of this invention; and 
           [0012]      FIG. 4  is a circuit diagram illustrating the method of breaking the overcurrent in a preferred embodiment of this invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0013]    Now, the present invention will be described more specifically with reference to the following embodiments. It is to be noted that the following descriptions of preferred embodiments of this invention are presented herein for purpose of illustration and description only; it is not intended to be exhaustive or to be limited to the precise form disclosed. 
         [0014]    Firstly, with reference to  FIGS. 2 through 4 , a method of breaking an overcurrent in a preferred embodiment of this invention mainly comprises the following steps: 
         [0015]    A. Connecting an overcurrent breaking controller  100  in series: 
         [0016]    One terminal of the controller  100  is connected in series to a load  200 , while the other terminal is connected in series to an AC power  300 . 
         [0017]    B. Triggering and controlling the load  200 : 
         [0018]    With a power source supplied by the AC power  300 , the overcurrent breaking controller  100  triggers and controls the load  200 . 
         [0019]    C. Detecting a current higher than a rated current: 
         [0020]    When starting to work, the load  200  consumes a power and generates a current in a loop and the controller  100  starts to detect the current generated with the power consumed by the load  200 ; when the current is higher than the rated current of the controller  100 , step D proceeds. 
         [0021]    D. Turning OFF the overcurrent breaking controller  100 : 
         [0022]    When detecting the current, being generated with the power consumed by the load  200 , which is higher than the rated current, the overcurrent breaking controller  100  does not turn ON, and thus a circuit between the load  200  and the AC power  300  stays open, thereby the controller  100  instantly stopping the load  200  working. 
         [0023]    E. Detecting a current lower than a rated current: 
         [0024]    When detecting the current passing through the load  200  that is lower than the rated current, the controller  100  allows the load  200  to re-work and step B proceeds. 
         [0025]    Thus, when detecting the connected load  200  of which the current generated with the consumed power is higher than the rated current of the overcurrent breaking controller  100 , the overcurrent breaking controller  100  instantly stops the load  200  working. When detecting the current passing through the load  200  that is lower than the rated current, the controller  100  allows the load  200  to re-work. The load  200  in the preferred embodiment of this invention is the lamp and lantern, in which the overcurrent breaking controller  100  connected in the method of breaking the overcurrent mainly comprises a current transformer  10 , a trigger control unit  20 , and an overcurrent restraint unit  30 . 
         [0026]    One terminal of the current transformer  10  is connected to the load  200 . The current transformer  10  mainly comprises a primary coil with small number of coils, and a secondary coil with large number of coils. In the preferred embodiment of this invention, a ratio of the primary coil to the secondary coil is set to 1:150. Thus, when a current passing through the load  200  increases, an induced current generated by the primary coil of the current transformer  10  increases and the induced voltage generated by the secondary coil increases, thereby the current transformer  10  being featured with an effect of amplification. 
         [0027]    One terminal of the trigger control unit  20  is connected to the AC power  300 , and the other terminal is connected to the current transformer  10  to trigger and control the load  200  connected to the other terminal of the current transformer  10 . The trigger control unit  20  is further a phase control circuit. In the preferred embodiment of this invention, the phase control circuit is a full wave phase control circuit, mainly comprising a Diode for Alternating Current (DIAC)  21  and a TRIode for Alternating Current (TRIAC)  22 , in which the DIAC  21  is connected in series to a Gate of the TRIAC  22 . Thus, the DIAC  21  that turns ON may trigger the TRIAC  22  so as to make the DIAC  21  further control the load  200 . 
         [0028]    One terminal of the overcurrent restraint unit  30  is connected to the current transformer  10 , while the other terminal is connected to the trigger control unit  20 . With reference to  FIG. 4 , the unit  30  comprises a half wave rectifier voltage division circuit  31 , a voltage regulator circuit  32 , a Silicon-Controlled Rectifier (SCR)  33 , a delay circuit  34 , and a bridge rectifier  35 . An anode terminal of the SCR  33  is connected to the bridge rectifier  35  and further to the DIAC  21  provided in the trigger control unit  20 . A terminal of the DIAC  21  that is connected to a charging and discharging capacitor is connected to the bridge rectifier  35 . The SCR  33  is further connected to the delay circuit  34 . In the preferred embodiment of this invention, the anode of SCR  33  is connected in parallel to a capacitor, the other terminal as Gate that is connected to the voltage regulator circuit  32  is further connected to the half wave rectifier voltage division circuit  31  of which the other terminal is connected to the secondary coil of current transformer  10 . In the preferred embodiment of this invention, the voltage regulator circuit  32  connects a Zener diode in series to the Gate terminal of SCR  33 . When the induced voltage generated in the secondary coil of current transformer  10  is more than the voltage in the voltage regulator circuit  32 , the SCR  33  is made to turn ON and further a voltage drop occurs in the charging and discharging capacitor of DIAC  21  connected to the bridge rectifier  35  so as to make the DIAC  21  not turn ON; at this time, the trigger control unit  20  stays at a non-trigger state. 
         [0029]    With reference to  FIG. 4  again, in the method of breaking the overcurrent, the overcurrent breaking controller  100  is connected in series between the AC power  300  and the load  200 . Thus, the power source supplied by the AC power  300  triggers the TRIAC  22  through the DIAC  21  of the trigger control unit  20  so as to make the DIAC  21  turn ON, and the AC power  300  supplies the power to the load  200  to work. At this time, the induced current is generated in the primary coil of current transformer  10  and converted and amplified into an induced voltage in the secondary coil. The induced voltage is a high voltage and, after being rectified and divided by the half wave rectifier voltage division circuit  31 , is detected by the voltage regulator circuit  32 . When the current that is generated due to the consumed power of the load  200  is higher than the rated current of the controller  100 , namely exceeding the predetermined current, the induced voltage generated in the secondary coil of current transformer  10  is also higher than the setting value of voltage of the regulator circuit  32  and the Zener diode in the regulator circuit  32  is made to turn ON; besides, the Gate terminal of SCR  33  is triggered so as to make the SCR  33  turn ON and constantly ON because of a time delay of the delay circuit  34 . At this time, the bridge rectifier  35  also takes effect so as to make the voltage generated by the charging and discharging capacitor of the DIAC  21  connected to the other terminal of the rectifier  35  drop. When the voltage passing through the DIAC  21  is lower than its trigger voltage, in this invention, the trigger voltage is 30V. Here, the DIAC  21  does not turn ON and not trigger the TRIAC  22 . The TRIAC  22  does not turn ON, so the circuit between the load  200  and the AC power  300  stays open. At present, the load current passing through the current transformer  10  drops and the load  200  stop working, thereby the overcurrent breaking control being achieved. When the current restraint circuit determines that the current generated from the power consumption of the load  200  is lower than the rated current, the trigger control unit  20  re-trigger the load  200  and the load  200  works again. Thus, the method of breaking the overcurrent not only allows the controller  100  to be simply connected in series between the load  200  and the AC power  300  for protection, but also prevent the load  200  from being randomly replaced with the load  200  of which the current or power is higher than the rated one for achievement of energy economization. 
         [0030]    While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.