Abstract:
A portable ground fault circuit breaker includes a main housing. An interior housing in which moving and static contacts are disposed is disposed inside the main housing and includes a base and a base cover. The static contacts are hung in the interior housing. The moving contacts are disposed on an unbalancing moving contact frame. A trip lock is disposed at one end of the moving contact frame and connected to a fasten lock fulfilling the separation and connection of the moving and static contacts. A lower portion of the fasten lock penetrates the base to abut on a tripping solenoid disposed at an exterior bottom of the base. The solenoid and a main control circuit on a circuit board fulfill an electrical connection. A simple structure, a small bulk, use convenience, and a humanized appearance design are the effects.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a protection device for electrical appliances, in particular a portable ground fault circuit breaker which interrupts the power of the load side automatically when there is a short circuit, an electricity leakage, an electricity shock, a ground fault, and a neutral ground fault. The breaker also possesses protection functions, such as a water-proof protection. 
     2. Description of the Related Art 
     In recent years, fire disasters caused by the short-circuited electrical appliances results in a great loss of human&#39;s lives and properties. A further development attendant on the science technique is that people start to design protection devices for these electrical appliances. However, these devices have a poor protection performance generally and provide a narrow application scope. Especially, most protection devices in the market do not have a short-circuited protection function or do not arrange a rational structure even if they have the short-circuited protection function. For example, the devices may lack a function of arc extinction, which creates electric sparks at time of closing, breaks the circuit and the load immediately, and reduces the use duration and comprehensive performances. 
     There is disclosed a prior art published by a China patent no. ZL 200810147046.0 and titled by “fire-proof and electricity-leakage proof protecting plug” with a short-circuited protection function. As referring to  FIG. 1  which is a schematic view showing a tripping structure of the disclosure and  FIG. 2  which is a circuit diagram of the disclosure, the prior art includes a tripping solenoid and a multifunctional protection auxiliary circuit installed on a base plate on which a moving iron core sleeved by tripping coils and a framework are all installed, an insulation plate fixedly disposed at a center of a moving contact sheet, a permanent magnet fixedly installed on a place where a pole of the insulation plate and a static iron core on a plug housing are attracted. When a load end of the plug has an overload, an overpressure, an electricity leakage, a short circuit, and/or the plug is overheated, a protection circuit controls the moving iron core for creating magnetism, and the magnetism and the magnetism of the permanent magnet are repulsive. This repulsion drives the permanent magnet to activate a downward motion of the insulation plate and the moving contact sheet, thereby causing a disjunction between the moving and the static contact points and fulfilling a tripping operation. 
     The above technique has a high sensibility and a quick power-off speed (e.g. power-off within 25 ms). However, the prior art only utilizes the tripping solenoid to fulfill the opening operation. The shortcoming attendant on the mechanism is that it needs enough certain maintenance force to keep the opening/closing state. In other words, when the permanent magnet drives the moving contact sheet to leave the static contact sheet, the moving iron core must reserve a generation of the strong magnetism repulsing the permanent incessantly for assuring the opening safety. However, once the opening operation is obtained, the strong current in the circuit would disappear and subsequently the moving iron core would lose the magnetism incessantly. Due to an elastic and transmutable U-shaped component disposed at one end where the moving contact sheet and the base plate are fixed, the permanent magnet on the insulation plate disposed on the component may be possibly attracted by the static iron core again without the force of incessant repulsion, and such attraction possibly would drive the moving and the static contact sheets to contact with each other again and cause the closing operation, which results in an extreme hidden trouble to the safety. 
     As referring to  FIG. 2  of the disclosure, it is understood that the tripping solenoid is executed by a silicon controlled rectifier to attain the protection against the short circuit, overload, overpressure, electricity leakage or overheat, which however imposes on the silicon controlled rectifier heavily, affects the duration, and increases the hidden trouble to the safety, especially when the short circuit happens. 
     A further shortcoming is that when the moving contact sheet, the static contact sheet, and the tripping solenoid and the multifunctional protection auxiliary circuit installed on a base plate are all disposed in a smaller space, an electric arcs created by closing the moving and the static contact sheets would inevitably affect or even burn up the tripping solenoid and the multifunctional protection auxiliary circuit. 
     To solve the shortcomings attendant on the current technique, the inventor of the present invention develops a portable ground fault circuit breaker by combing his abundant technical experiences, the structure of which fulfills a decisive circuit-break effect by opening swiftly and safely, needs not an incessant current supply, and prevents the loss of electrical energy. The present invention also has a compact and scientific structure and possesses a water-proof protection and the function of protecting against the overload, the electricity leakage, the electricity shock, the ground fault and the neutral ground fault, and the short circuit. 
     SUMMARY OF THE INVENTION 
     To attain the above functions and solve the shortcomings of the current technique, the present invention provides a portable ground fault breaker which combines a tripping solenoid with a lever tripping mechanism skillfully and scientifically and has an extreme high stability and sensibility. The present invention does not create electric sparks and has a long duration. It is also not suitable for heating. 
     The technical problem solved by the present invention is obtained by the following technique: 
     A portable ground fault circuit breaker includes a main housing, charaterised in that an interior housing is further disposed inside the main housing and comprises a base and a base cover. The interior housing is fixedly disposed on a circuit board in the main housing via a base leg which is disposed on the base; 
     at least two static contact frames with respective static contacts are soldered to the circuit board and respectively located at two sides of a base cover. The static contacts pass through a top part of the base cover and hangs in the interior housing; 
     in the interior housing are at least two moving contact sheets which provide moving contacts and are separated by an insulation plate disposed on an unbalancing moving contact frame respectively. A trip lock is disposed at one end of the moving contact frame, and the trip lock is connected to a fasten lock which functions as a balance and allows the moving contacts to separate from and combine with the static contacts; and 
     a upper portion of the fasten lock is hung on the base cover through a rotating axle. A lower portion of the fasten lock passes through the base for being in contact with a tripping solenoid disposed at an exterior bottom of the base. The tripping solenoid and a main control circuit disposed on the circuit board are in an electrical connection. 
     There is also disclosed the further technical innovation of the present invention, wherein the tripping solenoid includes a coil framework, a tripping coil and a magnetic yoke disposed on the coil framework, a moving iron core, an iron core spring sleeved on one end of the moving iron core, and a push rod frame disposed around the coil framework; wherein the coil framework is hung on the exterior bottom of the base through a fixing device; 
     wherein a protruding platform is further disposed on the coil framework for a placement of the push rod frame, two sides of the push rod frame are located on the protruding platform, and the push rod frame can have a free reciprocating motion within a space formed between the protruding platform and the exterior bottom of the base; and 
     wherein one end of the moving iron core passes through the coil framework and one side of the magnetic yoke for being located inside the tripping coil, and the other end of the moving iron core with the iron core spring sleeved thereon is disposed out of the tripping coil and jammed into one side of the push rod frame. The other side of the push rod frame is in a free contact with the lower portion of the fasten lock. 
     There is also disclosed another technical innovation of the present invention, wherein a protrusion with a bevel surface is formed at a middle portion of the fasten lock, and a bottom of the protrusion is formed into a level state to restrict the action of the trip lock; 
     wherein the lower portion of the fasten lock is bended. One end of a fasten lock spring is in an elastic and free contact with the lower portion of the fasten lock, and the other end thereof is fixed to the base cover. 
     There is also disclosed another technical innovation of the present invention, wherein a reset button fixing seat with a hollow interior having a top communicated with a bottom is disposed on the base cover, and at least one locking mouth is formed on the reset button fixing seat; 
     wherein one end of a reset button passes through the reset button fixing seat to be in contact with the moving contact frame. A return spring is sleeved on that end of the reset button. The return spring is limited within the reset button fixing seat; 
     wherein at least one elastic lock which fits in the locking mouth is disposed at a middle part of the reset button, and the elastic lock is formed into an inverted cone shape, thereby efficiently preventing the reset button from randomly escaping upwards when it is moved downwards and assuring the stability of the closing status; and 
     wherein the other end of the reset button passes through a sealing press plate disposed inside the main housing for being located within a water proof button sealing unit disposed out of the main housing 
     There is also disclosed another technical innovation of the present invention, wherein a test contact sheet is disposed on the base cover. The test contact sheet is elastically in contact with the static contact frame. One end of a test button is in contact with the test contact sheet, and the other end thereof passes through the sealing press plate for being connected to the water proof button sealing unit disposed out of the main housing. 
     There is also disclosed another technical innovation of the present invention, wherein a tubular body for fixing a high brightness light emitting diode is disposed on the base cover, and two sides of the tubular body forms notches penetrated by solder pins respectively. One end of the solder pin is soldered to the circuit board, and the other end thereof passes through the notch for being connected to the high brightness light emitting diode which is fixed to the tubular body; 
     wherein the high brightness light emitting diode passes through the sealing press plate for being set inside the indication lampshade which is disposed out of the main housing. 
     There is also disclosed another technical innovation of the present invention, wherein at least one recess is inwardly formed on an interior bottom of the base, which ensures a safe interstice of opening when the moving contact frame falls; 
     wherein two limiting members are extended upwardly from the interior bottom of the base and located at two sides of the trip lock respectively, thereby limiting a level swing of the trip lock for ensuring the safety of opening and closing operations. 
     There is also disclosed another technical innovation of the present invention, wherein a lever fulcrum with a hemispherical top is further disposed on the interior bottom of the base. One end of a contact spring is sleeved on the lever fulcrum, and the other end thereof is fixed to a bottom of the moving contact frame; 
     wherein a blocking frame is disposed at two sides of the base for limiting displacements of the moving contact frame and the base cover. Preferably, the present invention arranges two pairs of blocking frames at two sides of the base. The base cover and the base are engaged to constitute the interior housing, which allows the moving contact and the static contact to fulfill the opening and the closing operations within an individual space constituted by the interior housing and prevents the electric arcs caused by closing from interfering with the circuit board and the tripping solenoid. 
     There is also disclosed another technical innovation of the present invention, wherein the main housing comprises a top cover, a bottom seat, and a small bottom cover; wherein the circuit board is disposed on the bottom seat through a fixing pillar, a blocking plate is disposed on the small bottom cover, one end of a connecting terminal for connecting a load is disposed on the blocking plate, and the other end of the connecting terminal is connected to the moving contact sheet; 
     wherein the bottom seat and the small bottom cover are hermetically connected to the top cover through a surrounding sealing body, and the water proof button sealing unit and the indication lampshade are all disposed on the top cover; 
     wherein a wire clamping plate is hung on the top cover through a fixing unit and located above the small bottom cover for fixing the output wire; and 
     wherein a conductor sealing ring is hermetically and fixedly disposed between the small bottom cover and the top cover through a wedging unit for executing a hermetical connection of the load wire. 
     There is also disclosed another technical innovation of the present invention, wherein a peripheral circuit A, a test circuit B, a power switch circuit C, an indication circuit D, a detection and inductance circuit E, a main control circuit F, and a signal amplification circuit G are disposed on the circuit board; wherein the detection and inductance circuit E includes an electricity leakage and electricity shock ground fault detection and inductance circuit E 1 , a neutral ground fault detection circuit E 2 , and a short-circuited detection circuit E 3 . The main control circuit F includes an electricity leakage and electricity shock ground fault control circuit F 1 , a neutral ground fault control circuit F 2 , and a short-circuited control circuit F 3 . 
     The peripheral circuit A includes a varistor MOV disposed on the circuit board and a power phase wire L and a power neutral wire N connected to a power. The varistor MOV is connected to the power phase wire L and the power neutral wire N for absorbing the pulse voltage in the electrical grid and protecting the circuit. 
     The test circuit B includes a test resistance R test, a test switch K twst, and a conductor disposed on the circuit board; wherein the resistance R test and the conductor are soldered to the circuit board. The test switch K twst includes the test button and the test contact sheet for inspecting the integrity of the performance of the portable ground fault breaker. 
     The power switch circuit C includes a double-pole single-throw switch K with a trip-free mechanism disposed inside the interior housing and a tripping solenoid hung on the exterior bottom of the base. The tripping solenoid controls the break of the double-pole single-throw switch K directly to protect the circuit and the load. 
     The indication circuit D includes a current-limit resistor R 7  disposed on the circuit board and a high brightness light emitting diode DL connected to the circuit board through the solder pin for displaying the working status. The shining state of the high brightness light emitting diode DL represents a normal operation, and the non-shining state thereof represents the non-electrification and shows the load with no power output. 
     The detection and inductance circuit E includes an electricity leakage and electricity shock ground fault detection and inductance circuit E 1 , a neutral ground fault detection circuit E 2 , and a short-circuited detection circuit E 3 ; wherein the electricity leakage and electricity shock ground fault detection and inductance circuit E 1  and the neutral ground fault detection circuit E 2  include zero sequence current mutual inductors T 1  and T 2  soldered to the circuit board and a power phase wire L and a power neutral wire N passing through T 1  and T 2 . They further include resistances R 1  and R 2 , capacitances C 1  and C 2 , a resistance R 5 , and capacitances C 5  and C 6  soldered to the circuit board. When the circumstances of the electricity leakage, the electricity shock, the ground fault, and the neutral ground fault happen to the load wire, T 1  and T 2  detect, amplify and send the signal to the signal amplification circuit G; 
     The short-circuited detection circuit E 3  includes a ring-shaped mutual inductor T 3  soldered to the circuit board, a power phase wire L passing through T 3 , and a resistance R 6 , a capacitance C 7  and diodes D 1 -D 4  soldered to the circuit board; wherein, every two diodes in a series connection are connected to the short-circuited detection circuit E 3 . A positive diode voltage of each diode is decreased to 0.7V. When the circuit is short-circuited, T 3  detects and inspects the signal, and then the signal is limited and rectified by the diodes D 1 -D 4  and sent to the silicon controlled rectifier for activating and turning on the tripping solenoid to open the moving and the static contacts, thereby interrupting the power. 
     The signal amplification circuit G includes a resistance R 3 , a capacitance C 3 , and an integrated circuit IC disposed on the circuit board. The signal amplification circuit G receives the signals of T 1  and T 2 , executes the signal detection and amplification, analyzes whether the signals are correct to prevent error signals, and thence sends the detected, amplified, and correct signals to the next-grade main control circuit F. 
     The main control circuit F includes an electricity leakage and electricity shock ground fault control circuit F 1 , a neutral ground fault control circuit F 2 , and a short-circuited control circuit F 3 ; wherein, the electricity leakage and electricity shock ground fault control circuit F 1  and the neutral ground fault control circuit F 2  include a silicon controlled rectifier SCR 1 , a resistance R 4 , a capacitance C 4 , and a bridge rectification circuit DB; wherein the bridge rectification circuit DB is constituted by four diodes. The electricity leakage and electricity shock ground fault control circuit F 1  receives the electricity leakage and electricity shock ground fault signal of the former-grade signal amplification circuit G and loads it to the silicon controlled rectifier SCR 1 . When the circumstances of the ground fault or the neutral ground fault oscillation frequency happen to the load wire, the resistance RSENSE is set as a feedback resistance with a gain and a fault sensibility for maintaining the loop gain and oscillating. The frequency is determined by the coefficient of self-inductance of the mutual inductor with the coil 200:1 of T 2  and C 5  as well as C 6  and RSENSE. The following means is taken at time of adjusting the resistance RSENSE: apply expected error currents and adjust the value of the resistance RSENSE until the silicon controlled rectifier SCR 1  activates. Likewisely, a fixing resistance can be adopted as the resistance RSENSE because the variation of sensibility ranging ±15% can also satisfy the regulation scope of 4-6 mA in UL943. The sensibility of the neutral ground fault is adjustable by changing the oscillation frequency. The reduction of the loop gain of the positive feedback circuit can increase the frequency for decreasing the sensibility. When the frequency increases, the signal is attenuated and the loop gain is weakened. When the neutral ground fault happens to the circuit, the resistance is 2Ω or even less. It is amplified and protected through the integrated circuit. In particular, a turn-on threshold voltage of the silicon controlled rectifier SCR 1  of the present invention is 0.6V, which is faster than the induction velocity of the silicon controlled rectifier of the current technique. The silicon controlled rectifier SCR 1  makes the next-grade circuit through. A tripping coil of the tripping solenoid is electrified to create a magnetic field immediately. Under the action of the magnetic yoke, the aggregated magnetism absorbs the moving iron core swiftly, and the moving iron core drives the push rod frame to move toward the fasten lock quickly. The push rod frame pushes the fasten lock away and compresses the fasten lock spring until the fasten lock separates from the trip lock. The moving contact sheet is unbalanced instantly under the gravity force. Then the end with the moving contact falls into the recess swiftly, whereby an instant break of the moving contact and the static contact is fulfilled to interrupt the circuit and obtain the protection. 
     The short-circuited control circuit F 3  includes a silicon controlled rectifier SCR 2  disposed on the circuit board and a resistance R 6 , a capacitance C 7  and diodes D 1 -D 4  disposed on the circuit board. The short-circuited control circuit F 3  receives the short-circuited signal sent by the signal amplification circuit G and loads it to the silicon controlled rectifier SCR 2  for turning on. In particular, the turn-on threshold voltage of the silicon controlled rectifier SCR 2  of the present invention is also 0.6V, which is faster than the induction velocity of the silicon controlled rectifier of the current technique. The silicon controlled rectifier SCR 2  makes the next-grade circuit through. A tripping coil of the tripping solenoid is electrified to create a magnetic field immediately. Under the action of the magnetic yoke, the aggregated magnetism absorbs the moving iron core swiftly, and the moving iron core drives the push rod frame to move toward the fasten lock quickly. The push rod frame pushes the fasten lock away and compresses the fasten lock spring until the fasten lock separates from the trip lock. The moving contact sheet is unbalanced instantly under the gravity force. Then the end with the moving contact falls into the recess swiftly, whereby an instant break of the moving contact and the static contact is fulfilled to interrupt the load-side circuit and obtain the protection. 
     The present invention obtains effects, such as a simple structure, a small bulk, use convenience, and a humanized appearance design. The present invention further provides protections against the electricity leakage, the electricity shock, the ground fault, the neutral ground fault, and the short circuit. The present invention breaks the load-side live wire and the neutral wire concurrently and provides a water-proof protection. The present invention does not generate electric sparks and has the function of obtaining a long duration and being not suitable for heating. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view showing a tripping device of the conventional patent technique; 
         FIG. 2  is a circuit diagram of the conventional patent technique; 
         FIG. 3  is a schematic view showing the assemblage of the portable ground fault breaker of the present invention; 
         FIG. 4  is a schematic view showing the tripping solenoid of the portable ground fault breaker of the present invention; 
         FIG. 5  is a schematic view showing the moving contact of the portable ground fault breaker of the present invention; 
         FIG. 6  is a schematic view showing the base cover of the interior housing of the portable ground fault breaker of the present invention; 
         FIG. 7  is a schematic view showing the base of the interior housing of the portable ground fault breaker of the present invention; 
         FIG. 8  is a circuit diagram of the portable ground fault breaker of the present invention; 
         FIG. 9  is a schematic view showing the modification of the structure in the preferred embodiment 2 of the portable ground fault breaker of the present invention; 
         FIG. 10  is a circuit diagram in the preferred embodiment 3 of the portable ground fault breaker of the present invention; and 
         FIG. 11  is a circuit diagram in the preferred embodiment 3 of the portable ground fault breaker of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The advantages of the present invention over the known prior arts are more apparent to those of ordinary skilled in the art upon reading following descriptions in junction with the drawings. 
     Referring to  FIGS. 3-7 , a preferred embodiment 1 of a portable ground fault circuit breaker of the present invention includes a main housing  101 . The main housing  101  is constituted by a top cover  1 , a bottom seat  2 , and a small bottom cover  3 ; wherein, the bottom seat  2  and the small bottom cover  3  are hermetically connected to the top cover  1  through a surrounding sealing body  4 . A water proof button sealing unit  5  and an indication lampshade  6  are disposed on a top of the top cover  1 . A conductor sealing ring mouth  8  with a slot  7  is disposed at an end of the top cover  1 . A conductor sealing ring  9  is lodged in the conductor sealing ring mouth  8  through a wedging unit  10  disposed thereon to fulfill a hermetical connection of the load wire. A wire clamping plate  11  is located at an inner side of the conductor sealing ring mouth  8  and set above the small bottom cover  3 . The wire clamping plate  11  is fixedly disposed in an interior of the top cover  1  through a fixing unit for fixing the output wire. 
     A fixing pillar  12  is disposed in the middle of an interior of the bottom seat  2  for supporting and fixing a circuit board  13 . A pin hole  15  penetrated by a pin  14  is formed on the bottom seat  2 . One end of the pin  14  passes through the pin hole  15  for being located out of the bottom seat  2 , and the other end thereof is in contact with a static contact frame  16  soldered to the circuit board  13 . A static contact  17  is further disposed on the static contact frame  16 ; wherein the pin  14  includes a power phase wire pin L, a power neutral pin N, and a ground pin E. The power phase wire L, the power neutral pin N, and two static contact frames  16  on the circuit board  13  are correspondingly connected to form a power input end. 
     A blocking plate  18  is disposed on the small bottom cover  3 . A wire connection frame  19  in charge of connecting the load is installed on the blocking plate  18 . A connecting plate  20  is disposed on the wire connection frame  19 . 
     An interior housing  102  is further disposed in the main housing  101 . The interior housing  102  is constituted by a base  21  and a base cover  22 ; wherein the base cover  22  is made of polymide 6 (PA6), which can absorb electric arcs caused by a closing operation and prevent electrical accidents. The static contact frame  16  with the static contact  17  penetrates the base cover  22  from two sides of the base cover  22  respectively and inserts into the base cover  22  to be in a hanging status. The base  21  is detachably fixed to the circuit board  13  through three base legs  23 . A lever fulcrum  24  with a hemispherical top is further disposed on an interior bottom of the base  21 . One end of a contact spring  25  is sleeved on the lever fulcrum  24 , and the other end thereof is fixed to a bottom of a moving contact frame  26 , which keeps an imbalance of the moving contact frame  26  without having an external balance force. 
     Two moving contact sheets  27  are respectively disposed at two sides of the moving contact frame  26 . The two moving contact sheets  27  are separated by an insulation plate  28 . One end of the moving contact sheet  27  sets a moving contact  29 , and the other end thereof is connected to the connecting plate  20  through a soft connection for forming a power output connected to the load. 
     A trip lock  30  is further disposed on the moving contact frame  26 . The trip lock  30  is connected to a fasten lock  31  which functions as a balance and drives a separation and a combination between the moving contact  29  and the static contact  17 . A upper portion of the fasten lock  31  is hung on the base cover  22  through a rotating axle  32 , and a lower portion thereof passes through the base  21  for being in contact with a tripping solenoid  103  hung on an exterior bottom of the base  21 . A protrusion  33  with a bevel surface is formed at a middle portion of the fasten lock  31 , and a bottom of the protrusion  33  is formed into a level state to restrict the action of the trip lock  30 . The lower portion of the fasten lock  31  is bended. One end of a fasten lock spring  34  is in an elastic and free contact with the lower portion of the fasten lock  31 , and the other end thereof is fixed to the base cover  22 . 
     A reset button fixing seat  35  with a top communicated with a bottom is disposed on a top of the base cover  22 . At least one locking mouth  36  is disposed on the reset button fixing seat  35 . One end of a reset button  37  passes through the reset button fixing seat  35  to be in contact with the moving contact frame  26 . A return spring  38  is sleeved on the end where the reset button  37  abuts on the moving contact frame  26 . The return spring  38  is limited within the reset button fixing seat  35  to fulfill the spring back of the reset button  37 . At least one elastic lock  39  which fits in the locking mouth  36  is disposed at a middle part of the reset button  37 , and the elastic lock  39  is formed into an inverted cone shape, thereby efficiently preventing the reset button  37  from randomly escaping upwards when it is moved downwards and assuring the stability of the closing status. The other end of the reset button  37  passes through a sealing press plate  40  disposed at the interior of the main housing  1  for being located within a button sealing unit  5 . 
     A test contact sheet  41  is further disposed on the base cover  22 . The test contact sheet  41  is elastically in contact with the static contact frame  16 . One end of a test button  42  is in contact with the test contact sheet  41 , and the other end thereof passes through the sealing press plate  40  for being connected to the water proof button sealing unit  5 . 
     A tubular body  44  for fixing a high brightness light emitting diode  43  is disposed on the base cover  22 . Two sides of the tubular body  44  forms notches  46  penetrated by solder pins  45  respectively. One end of the solder pin  45  is soldered to the circuit board  13 , and the other end thereof passes through the notch  46  for being connected to the high brightness light emitting diode  43  which is fixed to the tubular body  44 . The high brightness light emitting diode  43  penetrates the sealing press plate  40  for being set inside the indication lampshade  6 . 
     The tripping solenoid  103  of the present invention includes a coil framework  47 , a tripping coil  48  and a magnetic yoke  49  disposed on the coil framework  47 , a moving iron core  50 , an iron core spring  51  sleeved on one end of the moving iron core  50 , and a push rod frame  52  disposed around the coil framework  47 ; wherein the coil framework  47  is hung on the exterior bottom of the base  21  through a fixing device. 
     A protruding platform  53  is further disposed on the coil framework  47  for a placement of the push rod frame  52 , two sides of the push rod frame  52  are located on the protruding platform  53 , and the push rod frame  53  has a free reciprocating motion within a space formed between the protruding platform  53  and the exterior bottom of the base  21 . 
     One end of the moving iron core  50  passes through the coil framework  47  and one side of the magnetic yoke  49  for being located inside the tripping coil  48 , and the other end of the moving iron core  50  with the iron core spring  51  sleeved thereon is disposed out of the tripping coil  48  and jammed into one side of the push rod frame  52 . The other side of the push rod frame  52  is in a free contact with the lower portion of the fasten lock  31 . 
     At least one recess  54  is inwardly formed on an interior bottom of the base  21 , which ensures a safe interstice of opening when the moving contact frame  26  falls. 
     Two limiting members  55  are extended upwardly from the interior bottom of the base  21  and located at two sides of the trip lock  30  respectively, thereby limiting a level swing of the trip lock  30  for ensuring the safety of opening and closing operations. 
     A blocking frame  56  is disposed at two sides of the base  21  for limiting displacements of the moving contact frame  26  and the base cover  22 . Preferably, the present invention arranges two pairs of blocking frames  56  at two sides of the base  21 . The base cover  22  and the base  21  are engaged to constitute the interior housing  102 , which allows the moving contact  29  and the static contact  17  to fulfill the opening and the closing operations within an individual space constituted by the interior housing  102  and prevents the electric arcs caused by closing from interfering with the circuit board  13  and the tripping solenoid  103 . 
     Referring to  FIG. 8 , a peripheral circuit A, a test circuit B, a power switch circuit C, an indication circuit D, a detection and inductance circuit E, a main control circuit F, and a signal amplification circuit G are disposed on the circuit board  13 ; wherein the detection and inductance circuit E includes an electricity leakage and electricity shock ground fault detection and inductance circuit E 1 , a neutral ground fault detection circuit E 2 , and a short-circuited detection circuit E 3 . The main control circuit F includes an electricity leakage and electricity shock ground fault control circuit F 1 , a neutral ground fault control circuit F 2 , and a short-circuited control circuit F 3 . 
     The peripheral circuit A includes a varistor MOV disposed on the circuit board  13  and a power phase wire L and a power neutral wire N connected to a power. The varistor MOV is connected to the power-side power phase wire L and the power neutral wire N for absorbing the pulse voltage in the electrical grid and protecting the circuit. 
     The test circuit B includes a test resistance R test, a test switch K twst, and a conductor disposed on the circuit board  13 ; wherein the resistance R test and the conductor are soldered to the circuit board  13 . The test switch K twst includes the test button  42  and the test contact sheet  41  for inspecting the integrity of the performance of the portable ground fault breaker. 
     The power switch circuit C includes a double-pole single-throw switch K disposed inside the interior housing  102  and a tripping solenoid  103  hung on the exterior bottom of the base  21 . The tripping solenoid  103  controls the break of the double-pole single-throw switch K directly to protect the circuit and the load. 
     The indication circuit D includes a current-limit resistor R 7  disposed on the circuit board  13  and a high brightness light emitting diode  43  (DL) connected to the circuit board  13  through the solder pin  45  for displaying the working status. The shining state of the high brightness light emitting diode  43  (DL) represents a normal operation, and the non-shining state thereof represents the non-electrification and shows the load with no power output. 
     The detection and inductance circuit E includes an electricity leakage and electricity shock ground fault detection and inductance circuit E 1 , a neutral ground fault detection circuit E 2 , and a short-circuited detection circuit E 3 ; wherein the electricity leakage and electricity shock ground fault detection and inductance circuit E 1  and the neutral ground fault detection circuit E 2  include a zero sequence current mutual inductor T 1  and a mutual inductor T 2  soldered to the circuit board  13  and a power phase wire L and a power neutral wire N passing through T 1  and T 2 . They further include resistances R 1  and R 2 , capacitances C 1  and C 2 , a resistance R 5 , and capacitances C 5  and C 6  soldered to the circuit board  13 . When the circumstances of the electricity leakage, the electricity shock, the ground fault, and the neutral ground fault happen to the load wire, T 1  and T 2  detect, amplify and send the signal to the signal amplification circuit G. 
     The short-circuited detection circuit E 3  includes a ring-shaped mutual inductor T 3  soldered to the circuit board  13 , a power phase wire L passing through T 3 , and a resistance R 6 , a capacitance C 7  and diodes D 1 -D 4  soldered to the circuit board  13 ; wherein, every two diodes in a series connection are connected to the short-circuited detection circuit E 3 . A positive diode voltage of each diode is decreased to 0.7V. When the circuit is short-circuited, T 3  detects, inspects and amplifies the signal, and then the signal is limited and rectified by the diodes D 1 -D 4  and sent to the silicon controlled rectifier SCR 1 . The silicon controlled rectifier SCR 1  activates and makes the tripping solenoid turned on to open the moving and the static contacts, thereby interrupting the power. 
     The signal amplification circuit G includes a resistance R 3 , a capacitance C 3 , and an integrated circuit IC disposed on the circuit board  13 . The signal amplification circuit G receives the signals of T 1 , T 2 , and T 3 , executes the signal detection and amplification, analyzes whether the signals are correct in order to prevent error signals, and thence sends the detected, amplified, and correct signals to the next-grade main control circuit F. 
     The main control circuit F includes an electricity leakage and electricity shock ground fault control circuit F 1 , a neutral ground fault control circuit F 2 , and a short-circuited control circuit F 3 ; wherein, the electricity leakage and electricity shock ground fault control circuit F 1  and the neutral ground fault control circuit F 2  include a silicon controlled rectifier SCR 1  disposed on the circuit board  13 , and a resistance R 4 , capacitances C 3  and C 4 , and a bridge rectification circuit DB disposed on the circuit board  13 ; wherein the bridge rectification circuit DB is constituted by four diodes. The electricity leakage and electricity shock ground fault control circuit F 1  and the neutral ground fault control circuit F 2  receive the electricity leakage and electricity shock ground fault signal of the former-grade signal amplification circuit G and load it to the silicon controlled rectifier SCR 1  for turning on. In particular, a turn-on threshold voltage of the silicon controlled rectifier SCR 1  of the present invention is 0.6V, which is faster than the induction velocity of the silicon controlled rectifier of the current technique. The silicon controlled rectifier SCR 1  makes the next-grade circuit through. A tripping coil  48  of the tripping solenoid  103  is electrified to create a magnetic field immediately. Under the action of the magnetic yoke  49 , the aggregated magnetism absorbs the moving iron core  50  swiftly, and the moving iron core  50  drives the push rod frame  52  to move toward the fasten lock  31  quickly. The push rod frame  52  pushes the fasten lock  31  away and compresses the fasten lock spring  34  until the fasten lock  31  separates from the trip lock  30 . The moving contact sheet  26  is unbalanced instantly under the gravity force. Then the end with the moving contact  29  falls into the recess  54  swiftly, whereby an instant break of the moving contact  29  and the static contact  17  is fulfilled to interrupt the circuit and obtain the protection. 
     The short-circuited control circuit F 3  includes a silicon controlled rectifier SCR 2  disposed on the circuit board  13  and a resistance R 6 , a capacitance C 7  and diodes D 1 -D 4  disposed on the circuit board  13 . The short-circuited control circuit F 3  receives the short-circuited signal and loads it to the silicon controlled rectifier SCR 2  for turning on. In particular, the turn-on threshold voltage of the silicon controlled rectifier SCR 2  of the present invention is also 0.6V, which is faster than the induction velocity of the silicon controlled rectifier of the current technique. The silicon controlled rectifier SCR 2  makes the next-grade circuit through. A tripping coil  48  of the tripping solenoid  103  is electrified to create a magnetic field immediately. Under the action of the magnetic yoke  49 , the aggregated magnetism absorbs the moving iron core  50  swiftly, and the moving iron core  50  drives the push rod frame  52  to move toward the fasten lock  31  quickly. The push rod frame  52  pushes the fasten lock  31  away and compresses the fasten lock spring  34  until the fasten lock  31  separates from the trip lock  30 . The moving contact sheet  26  is unbalanced instantly under the gravity force. Then the end with the moving contact  29  falls into the recess  54  swiftly, whereby an instant break of the moving contact  29  and the static contact  17  is fulfilled to interrupt the circuit and obtain the short-circuited protection. 
     The operation principle and steps of the present invention are shown in the following description. According to the above technical measure, the assemblage of the portable ground fault breaker is completed to make sure that the main control circuit F and the tripping solenoid  103  fulfill an electrical connection and the breaker is connected to the load. 
     When the reset button  37  is pressed, the push of the reset button  37  compresses the contact spring  25  and the fasten lock spring  34  concurrently. The moving contact frame  26  brings the trip lock  30  sliding downwardly along the middle bevel surface of the fasten lock  31  until the trip lock  30  goes across the protrusion  33  and the trip lock  30  is stably positioned on the level bottom of the protrusion  33  of the fasten lock  31  under the elasticity of the fasten lock spring  34 . At the same time, the moving contact frame  26  drives the moving contact  29  to be in a dense contact with the static contact  17  hung in the interior housing  102  under the action of the lever fulcrum  24 , thereby obtaining a closing operation. Likewisely, the elastic lock  39  on the reset button  37  is lodged in the locking mouth  36 . If the portable ground fault breaker connects a power, the circuit can be turned on. Obviously, the present invention can press the reset button  37  to obtain the closing operation firstly and then make the portable ground fault breaker connect the power. 
     When the electricity leakage, the electricity shock, the ground fault, and the neutral ground fault oscillation frequency happen to the circuit, the detection and inductance circuit E detects the related information firstly and then sends the information to the signal amplification circuit G. The signal amplification circuit G inspects, amplifies, then analyzes whether the signal is correct, and thence sends the signal to the main control circuit F. The main control circuit F drives the silicon controlled rectifier SCR 1  or SCR 2  to turn on, which allows the tripping coil  48  of the tripping solenoid  103  to be electrified in order to create a magnetic field immediately. Under the action of the magnetic yoke  49 , the aggregated magnetism absorbs the moving iron core  50  swiftly, and the moving iron core  50  drives the push rod frame  52  to move toward the fasten lock  31  quickly. The push rod frame  52  pushes the fasten lock  31  away and compresses the fasten lock spring  34  until the fasten lock  31  separates from the trip lock  30 . The moving contact sheet  26  is unbalanced instantly under the gravity force. Then the end with the moving contact  29  falls into the recess  54  swiftly, whereby an instant break of the moving contact  29  and the static contact  17  is fulfilled to interrupt the circuit and obtain the protection. 
     When the moving contact frame  26  drives the moving contact  29  to fall into the recess  54 , three resistant forces will need to be overcome for spring back: 1. a force of the bevel surface at the middle portion of the fasten lock  31  against the trip lock  30 ; 2. a force compressing the fasten lock spring  34 ; and 3. a force pushing the reset button  37 . Consequently, once the moving contact  29  separates from the static contact  17  instantly, it is impossible to obtain the closing operation by spring back automatically. If the closing operation is to be executed, the reset button  37  must be manually actuated. Furthermore, the closing operation is conducted in the individual space constituted by the interior housing  102 , so it does not interfere with the circuit board  13  or the tripping solenoid  103 . Therefore, the opening operation and the closing operation are very safe and reliable. 
     Referring to  FIG. 9 , a preferred embodiment 2 of the present invention still comprises the main structure and principle the same as the preferred embodiment 1, which are herein omitted. The following contents describe the improvement in this preferred embodiment. 
     In this embodiment, the moving contact frame  26  is installed on the blocking frame  56  through a fixing axle  57 , namely the fixing axle  57  passes through the base cover  22 , the moving contact sheet  27 , and the moving contact frame  26  and provides two ends thereof fixedly disposed to a top end of the blocking frame  56  at two sides of the base  21  for allowing the moving contact sheet  27  and the moving contact frame  26  to rotate freely. The reset button  37  is in contact with the trip lock  30 . The closing operation can be easily executed by pressing the reset button  37 , thereby saving costs and reducing the weight by omitting the arrangement of the contact spring  25  and the lever fulcrum  24 . 
     Referring to  FIG. 10  and  FIG. 11 , a preferred embodiment 3 of the present invention still comprises the main structure and principle the same as the preferred embodiment 1, which are herein omitted. The following contents describe the improvement in this preferred embodiment. 
     In this embodiment, the peripheral circuit A, the test circuit B, the power switch circuit C, the indication circuit D, the detection and inductance circuit E, the main control circuit F, and the signal amplification circuit G are still disposed on the circuit board  13 ; wherein the detection and inductance circuit E still includes an electricity leakage and electricity shock ground fault detection and inductance circuit E 1  and a neutral ground fault detection circuit E 2 . Herein, a short-circuited detection circuit E 3  is not included. The main control circuit F still includes an electricity leakage and electricity shock ground fault control circuit F 1  and a neutral ground fault control circuit F 2 . Herein, a short-circuited control circuit F 3  is not included. 
     The peripheral circuit A includes a varistor MOV disposed on the circuit board  13  and a power phase wire L and a power neutral wire N connected to a power. The varistor MOV is connected to the power phase wire L and the power neutral wire N for absorbing the pulse voltage in the electrical grid and protecting the circuit. 
     The test circuit B includes a test resistance R test, a test switch K twst, and a conductor disposed on the circuit board  13 ; wherein the resistance R test and the conductor are soldered to the circuit board  13 . The test switch K twst includes the test button  42  and the test contact sheet  41  for inspecting the integrity of the performance of the portable ground fault breaker. 
     The power switch circuit C includes a double-pole single-throw switch K disposed inside the interior housing  102  and a tripping solenoid  103  hung on the exterior bottom of the base  21 . The tripping solenoid  103  controls the break of the double-pole single-throw switch K directly to protect the circuit and the load. 
     The indication circuit D includes a current-limit resistor R 7  disposed on the circuit board  13  and a high brightness light emitting diode  43  (DL) connected to the circuit board  13  through the solder pin  45  for displaying the working status. The shining state of the high brightness light emitting diode  43  (DL) represents a normal operation, and the non-shining state thereof represents the non-electrification and shows the load with no power output. 
     The electricity leakage and electricity shock ground fault detection and inductance circuit E 1  and the neutral ground fault detection circuit E 2  include zero sequence current mutual inductors T 1  and T 2  soldered to the circuit board  13  and a power phase wire L and a power neutral wire N passing through T 1  and T 2 . They further include resistances R 1 , capacitances C 1  and C 2 , a resistance R 5 , and capacitances C 5  and C 6  soldered to the circuit board  13 . When the circumstances of the electricity leakage, the electricity shock, the ground fault, and the neutral ground fault happen to the load wire, T 1  and T 2  detect, amplify and send the signal to the signal amplification circuit G. 
     The signal amplification circuit G includes resistances R 2  and R 3 , a capacitance C 3 , and an integrated circuit IC disposed on the circuit board  13 . The signal amplification circuit G receives the signals of T 1  and T 2 , executes the signal detection and amplification, analyzes whether the signals are correct in order to prevent error signals, and thence sends the detected, amplified, and correct signals to the next-grade main control circuit F. 
     The electricity leakage and electricity shock ground fault control circuit F 1  and the neutral ground fault control circuit F 2  include a silicon controlled rectifier SCR 1  disposed on the circuit board  13 , and a resistance R 4 , capacitances C 3  and C 4 , and a bridge rectification circuit DB disposed on the circuit board  13 ; wherein the bridge rectification circuit DB is constituted by four diodes. The electricity leakage and electricity shock ground fault control circuit F 1  receives the electricity leakage and electricity shock ground fault signal of the former-grade signal amplification circuit G and loads it to the silicon controlled rectifier SCR 1  for turning on. In particular, a turn-on threshold voltage of the silicon controlled rectifier SCR 1  of the present invention is 0.6V, which is faster than the induction velocity of the silicon controlled rectifier of the current technique. The silicon controlled rectifier SCR 1  makes the next-grade circuit through. A tripping coil  48  of the tripping solenoid  103  is electrified to create a magnetic field immediately. Under the action of the magnetic yoke  49 , the aggregated magnetism absorbs the moving iron core  50  swiftly, and the moving iron core  50  drives the push rod frame  52  to move toward the fasten lock  31  quickly. The push rod frame  52  pushes the fasten lock  31  away and compresses the fasten lock spring  34  until the fasten lock  31  separates from the trip lock  30 . The moving contact sheet  26  is unbalanced instantly under the gravity force. Then the end with the moving contact  29  falls into the recess  54  swiftly, whereby an instant break of the moving contact  29  and the static contact  17  is fulfilled to interrupt the circuit and obtain the protection. 
     While we have shown and described the present invention with reference to the specific preferred embodiment, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.