Abstract:
An electronic fence system capable of guiding animals under training to return to a predetermined restricted area. The electronic fence generates electric shocks as the animals attempt to leave the predetermined restricted area and restrains the electrical shock when the animals return to the predetermined restricted area. The electronic fence includes a transmitter and a receiver. The transmitter transmits RF signals having a plurality of control signals such that different shock levels are generated responsive to the location of the animals within the predetermined restricted area. The receiver sets a shock wave level, selectively controls the generation of the electric shock and a high-frequency beep, automatically restrains the generation of the electric shock when an escaped animal returns to the predetermined restricted area, and generates an audible alarm and turns lamps on and off to indicate the location of the animal when it escapes from the predefined restricted area.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to an electronic fence, and more particularly, to an electronic fence capable of guiding animals under training to return to a predetermined restricted area, which automatically controls an electric shock level in response to the location of the restricted area when the animals attempt to escape from the restricted area to efficiently control the animals and judges correct positions of the animals so as not to generate an electrical shock when the animals are returned to the restricted area.  
         [0003]     2. Background of the Related Art  
         [0004]      FIG. 1  shows a conventional electronic fence. In  FIG. 1 , reference numeral  100  denotes a transmitter connected to a transmission wire antenna  110  for transmitting an electric wave. The transmitter  100  includes an electric shock level control lever  101  for setting the level of a shock wave to be applied to animals, an antenna checking lamp  102 , a power switch  103 , and a transmitter power level control lever  104 .  
         [0005]     The operation of the conventional electronic fence will now be explained.  
         [0006]     First of all, a user turns on the power switch  103  included in the transmitter  100  and operates the shock level control lever  101  of the transmitter  100  to set the level of the shock wave to be applied to the animals. In addition, the user operates the transmitter power level control lever  104  to set a predetermined transmitter power level. Then, the transmission wire antenna  110 , included in the electronic fence to prevent the animals from escaping, is operated to generate a signal.  
         [0007]     In this state, when an animal wearing a receiver approaches the fence, a receiving antenna receives the signal transmitted from the transmitter  100  and a detector demodulates the received signal into the original signal. When the demodulated signal is a shock wave, the receiver generates a shock wave having the level corresponding to the level of the transmitted signal through a pair of electrodes. Accordingly, the animal cannot get out of the transmission wire antenna  110 .  
         [0008]     However, the aforementioned electronic fence generates an electric shock having a constant level when the animal escapes from a restricted area, and thus it is not efficient. Furthermore, the electric shock is generated even when the escaped animal return to the restricted area. Thus, the animal cannot enter the electronic fence due to the electric shock so that the animal may run away.  
         [0009]     Animals can run in excitement at 100 Km/hour when they chase other animals or targets. Thus, the animals can escape the restricted area even when an electric shock is applied to them. Furthermore, the animals calm down and return slowly when they come back home. If an electric shock is given to the animals when they are returning to the restricted area, the animals run away so that they can be lost. Moreover, the runaway animals may die from car accidents in many cases.  
         [0010]     Furthermore, the conventional electronic fence cannot detect the moving directions of the animals when the animals escape from the restricted area.  
       SUMMARY OF THE INVENTION  
       [0011]     Accordingly, the present invention has been made to solve the above problems occurring in the prior art, and it is an object of the present invention is to provide an electronic fence capable of guiding animals under training to return to a predetermined restricted area, which automatically controls an electric shock level in response to the location of the restricted area when the animals attempt to escape from the restricted area to efficiently control the animals and judges correct positions of the animals so as not to generate electrical shock when the animals return to the restricted area.  
         [0012]     To accomplish the above object, according to the present invention, there is provided an electronic fence capable of guiding animals to return including: a transmitter for transmitting radio signals having different frequency bands such that different shock waves are generated in response to positions of an animal moving close to the boundary of a predetermined restricted area, and generating a control signal for indicating a selected function; and a receiver for setting a shock wave level and determining whether or not a beep is generated in response to a radio signal transmitted from the transmitter, selectively controlling the generation of the shock wave and beep, automatically restraining the generation of the shock wave when an escaped animal is returned to the restricted area, and generating the beep and turning lights on and off to indicate the location of the animal visually and aurally when an animal escapes from the restricted area.  
         [0013]     The transmitter includes: a power switch for providing power or blocking the supply of power; an AC-DC converter for converting AC power supplied through the power switch into DC power having a predetermined level; a function selection switch for selecting a function; an electric shock level control lever for setting the level of a shock wave (an electric shock); a transmitter power level control lever for controlling a transmitter power level; a frequency output circuit for controlling the transmitter power level under the control of the transmitter power level control lever; a microprocessor for generating a control signal for indicating the level set by the shock level control lever and the function selected by the function selection switch; an antenna loop confirming lamp, a beep selecting lamp, an electric shock selecting lamp and an automatic selecting lamp for indicating the antenna loop state, whether a beep is selected, whether the electric shock is selected and whether automatic selection is chosen, respectively, under the control of the microprocessor; a modulation circuit for modulating the control signal generated by the microprocessor into a carrier; a loop detection circuit connected to the modulation circuit to detect a loop and transmit the loop to the microprocessor; and first and second loop antennas for radiating the output signal of the modulation circuit to the space.  
         [0014]     The receiver includes: a power supply battery; a power controller for supplying the output voltage of the battery to each of the blocks of the receiver or blocking the supply of voltage and, when the receiver is not used, automatically blocking the power from being supplied to the receiver; a receiving antenna having a belt for receiving a signal transmitted from the first or second antenna of the transmitter; an RF amplifier for amplifying an RF signal received by the receiving antenna to a predetermined level; a detector for detecting only an intermediate frequency from the RF signal output from the RF amplifier and demodulating the detected intermediate frequency into the original signal; a microprocessor for selectively generating a shock wave generation control signal in response to the signal output from the detector, controlling the power supplied to the receiver to be automatically cut, and generating a sound control signal and a lamp driving control signal; a lamp driver for controlling the operations of a position confirming lamp and an operating lamp in response to the lamp driving control signal output from the microprocessor; an amplifier for amplifying the shock wave generation control signal output from the microprocessor to a predetermined level; a high-voltage transformer for boosting the pulse signal output from the amplifier to a high voltage and transmitting the high voltage to a shock wave output terminal, to output a shock wave; and a sound driver for controlling the operations of a buzzer and a horn according to the sound control signal output from the microprocessor. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which:  
         [0016]      FIG. 1  illustrates a conventional electronic fence;  
         [0017]      FIG. 2  illustrates a transmitter of an electronic fence according to the present invention;  
         [0018]      FIG. 3  illustrates a receiver of the electronic fence according to the present invention;  
         [0019]      FIG. 4  is a block diagram of the transmitter of the electronic fence according to the present invention; and  
         [0020]      FIG. 5  is a block diagram of the receiver of the electronic fence according to the present invention.] 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]     Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.  
         [0022]      FIG. 2  illustrates a transmitter  1  of an electronic fence according to the present invention, and  FIG. 4  is a block diagram of the transmitter  1  of the electronic fence according to the present invention. The transmitter  1  transmits radio signals having different frequency bands such that different shock waves are generated in response to positions of an animal moving close to the boundary of a predetermined restricted area. In addition, the transmitter  1  generates a control signal for indicating a selected function.  
         [0023]     Referring to  FIGS. 2 and 4 , the electronic fence of the present invention includes a power switch  2 , an AC-DC converter  10 , a function selection switch  5 , an electric shock level control lever  4 , a transmitter power level control lever  3 , a frequency output circuit  17 , a microprocessor  16 , an antenna loop confirming lamp  6 , a beep selecting lamp  7 , an electric shock selecting lamp  8 , an automatic selecting lamp  9 , a modulation circuit  14 , a loop detecting circuit  15 , and first and second loop antennas  11  and  13 . The power switch  2  provides power or blocks the supply of power. The AC-DC converter  10  converts AC power supplied through the power switch  2  into DC power having a predetermined level. The function selection switch  5  is used to select a function. The electric shock level control lever  4  sets the level of a shock wave (an electric shock). The transmitter power level control lever  3  controls a transmitter power level. The frequency output circuit  17  controls the transmitter power level under the control of the transmitter power level control lever  3 . The microprocessor  16  generates a control signal for indicating the level set by the shock level control lever  4  and the function selected by the function selection switch  5 . The antenna loop confirming lamp  6  indicates the antenna loop state and a beep selecting lamp  7  indicates whether a beep is selected or not under the control of the microprocessor. The electric shock selecting lamp  8  and automatic selecting lamp  9  respectively indicate whether the electric shock is selected and whether automatic selection is chosen under the control of the microprocessor  16 . The modulation circuit  14  modulates the control signal generated by the microprocessor  16  into a carrier. The loop detection circuit  15  is connected to the modulation circuit  14  and detects a loop to transmit the loop to the microprocessor  16 . The first and second loop antennas  11  and  13  radiate the output signal of the modulation circuit  14  to the space.  
         [0024]      FIG. 3  illustrates a receiver  21  of the electronic fence according to the present invention, and  FIG. 5  is a block diagram of the receiver  21  of the electronic fence according to the present invention. The receiver  21  sets a shock wave level and determines whether a beep is generated in response to a radio signal transmitted from the transmitter  1 , and selectively controls the generation of the shock wave and beep. In addition, the receiver  21  automatically restrains the generation of shock wave when an escaped animal is returned to the restricted area and, when an animal escapes from the restricted area, generates the beep and turns lights on and off to indicate the location of the animal visually and aurally.  
         [0025]     Referring to  FIG. 5 , the receiver includes a power supply battery  36 , a power controller  37 , a receiving antenna  28  including a belt, an RF (Radio Frequency) amplifier  29 , a detector  30 , a microprocessor  31 , a lamp driver  32 , an amplifier  33 , a high-voltage transformer  34 , a sound driver  35 . The power controller  37  supplies the output voltage of the battery  36  to each of the blocks of the receiver or blocks the supply of voltage and, when the receiver is not used, automatically blocks the power from being supplied to the receiver. The receiving antenna  28  receives a signal transmitted from the transmitter. The RF amplifier  29  amplifies an RF signal received by the receiving antenna  28  to a predetermined level. The detector  30  detects only an intermediate frequency from the RF signal output from the RF amplifier  29  and demodulates the detected intermediate frequency into the original signal. The microprocessor  31  selectively generates a shock wave generation control signal in response to the signal output from the detector  30 , controls the power supplied to the receiver to be automatically cut, and generates a sound control signal and a lamp driving control signal. The lamp driver  32  controls the operations of a position confirming lamp and an operating lamp in response to the lamp driving control signal output from the microprocessor  31 . The amplifier  33  amplifies the shock wave generation control signal output from the microprocessor  31  to a predetermined level. The high-voltage transformer  34  boosts the pulse signal output from the amplifier  33  to a high voltage and transmits the high voltage to a shock wave output terminal  23  to output a shock wave. The sound driver  35  controls the operations of a buzzer  24  and a horn  25  according to the sound control signal output from the microprocessor  31 .  
         [0026]     The operation of the electronic fence having the aforementioned configuration will now be explained.  
         [0027]     When the power switch  2  of the transmitter  1  is turned on while the first and second loop antennas  11  and  13  are located at different positions in a restricted area, the AC-DC converter  10  converts an input AC power into a DC power with a predetermined level and supplies the DC power to the transmitter power level control lever  3  and each of the blocks of the transmitter  1 .  
         [0028]     When the microprocessor  16  is provided with the power, it initializes the transmitter  1  and then converts the transmitter into a state in which the transmitter transmits a radio signal to the receiver  21 . In this state, when a user operates the shock level control lever  4  for setting a shock wave level, a corresponding control signal is transmitted to a central processing unit  16   d  of the microprocessor  16  through an input controller  16   c . Subsequently, when the user operates the function selection switch  5  to select a function, a lamp is turned on in response to the selected function such that the user can easily recognize the selected function.  
         [0029]     Then, the microprocessor  16  arranges transmission data in the order of a start signal, an address signal, function key data, shock wave level data and completion data and transmits the transmission data to the modulation circuit  14  when the microprocessor  16  judges that the user&#39;s operation is completed. The modulation circuit  14  modulates the transmission data into a carrier using an oscillation frequency. The carrier is radiated to the space through the first and second loop antennas  11  and  13 .  
         [0030]     The signal radiated through the first and second loop antennas  11  and  13  is transmitted to the receiver  21  and the function set in the transmitter  1  is operated in the receiver  21  when an animal wearing the receiver  21  approaches the first or second loop antenna. The receiver  21  includes a belt  22  such that the animal wears the receiver  21  using the belt  22 .  
         [0031]     In the operation of the receiver  21 , the output voltage of the power supply battery  36  is supplied to each of the blocks of the receiver  21  under the control of the power controller  37 . Then, the microprocessor  31  detects the output signal of the detector  30  to determine whether the receiver is operated or not. Here, the operation of the receiver  21  depends on whether the received signal is the output signal of the first loop antenna  11  or the output signal of the second loop antenna  13 . For example, when the receiver  21  receives the output signal of the first loop antenna  11  first, the receiver judges that an animal approaches the boundary of the restricted area to attempt to get out of the area and operates only the sound driver  35  to generate an alarm signal through the buzzer  24 .  
         [0032]     When the animal approaches to the boundary of the restricted area even when the alarm signal is generated, the microprocessor  31  generates a pulse-driving signal such that a level controller  31 C generates an electric shock having a low level. The pulse-driving signal is amplified by the amplifier  33  to a predetermined level and then transmitted to the high-voltage transformer  34 . The high-voltage transformer  34  boosts the amplified pulse-driving signal to a high voltage and applies the high voltage to a pair of electrodes  23  such that a shock wave is generated to stimulate the neck of the animal. Accordingly, the animal cannot move forward any more. Here, the generated shock wave is a weak shock wave.  
         [0033]     When the animal continuously attempts to get out of the restricted area even when the shock wave is generated and thus the receiver receives the signal of the second loop antenna  13 , the microprocessor  31  generates a pulse-driving signal such that the level controller  31 C generates an electric shock having a high level. This pulse-driving signal is amplified by the amplifier  33  to a predetermined level and then transmitted to the high-voltage transformer  33 . The high-voltage transformer  34  boosts the amplified pulse-driving signal to a high voltage and applies the high voltage to the electrodes  23  such that a shock wave is generated to stimulate the neck of the animal. Accordingly, the animal cannot move forward any more. Here, the generated shock wave is a strong shock wave.  
         [0034]     When the receiver  21  receives the signal of the second loop antenna  13  and then receives the signal of the first loop antenna  11  again, the receiver judges that the escaped animal attempts to return to the restricted area. When the receiver does not receive the signal of the first loop antenna  11  any more, the receiver determines that the animal has returned to the restricted area, stops the generation of shock wave, and returns to its initial state.  
         [0035]     However, when the receiver does not receive the signal of the second loop antenna  13  even after the signal of the second loop antenna  13  is received and the animal is kept from moving by the strongest electric shock, the receiver  21  judges that the animal has escaped from the restricted area and operates the horn  25  through the sound driver  35  to generate a loud beep such that the user can visually confirm the location of the animal.  
         [0036]     When the escaped animal returns to the restricted area and the receiver receives the signal of the second loop antenna  13 , the receiver restrains the generation of electric shock such that the animal can return to the original position.  
         [0037]     Furthermore, the microprocessor  31  checks a non-use time using a program. Specifically, the microprocessor  31  counts the time from the moment the receiver is finally used until the moment the receiver is used again, and finishes counting when the receiver is used. When the non-use time exceeds a predetermined period of time (5 hours, for example), the microprocessor  31  automatically generates a power control signal to the power controller  37 . Then, the power controller  37  blocks the output voltage of the battery  36  from being supplied to the blocks of the receiver  21  to prevent waste of power.  
         [0038]     The present invention uses a luminous reflection belt as the belt  22  in order to prevent the escaped animal from meeting with a car accident at night.  
         [0039]     As described above, the electronic fence of the present invention sets an electric shock level in response to the position of an animal moving close to the boundary of a restricted area. Thus, the animal can be restrained from escaping from the restricted area without giving an excessive electric shock to the animal. Furthermore, the present invention can generate a loud sound and bright light through the device connected to the belt the animal wears even when the animal gets out of the restricted area so that the location of the animal can be easily detected. Moreover, the present invention can restrain the generation of electric shock when the escaped animal return to the restricted animal and thus the animal can come back safely.  
         [0040]     While the present invention has been described with reference to the particular illustrative embodiments, it is not to be restricted by the embodiments but only by the appended claims. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.