Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a monitoring device of power line and camera, which ingrates single power line, signals, and power supply. 
     2. Description of the Related Art 
     When reversing a vehicle  80  as shown in  FIG. 1 , the driver must rely on the rearview mirror to detect objects in the rear of the vehicle  80 ; however, right behind the vehicle  80  is a dead space for detection. 
     The vehicle  80  such as the trailers, trucks has a tractor  801  to lead the container  802  so that it is not easy for drivers to detect objects surrounding the vehicle  80 . Moreover, the tractor  801  and container  802  are separated because of transportation considerations, resulting difficult wiring of transmission lines of power or signal for a monitoring device. 
     With the referenced to  FIG. 2 , the U.S. Pat. No. 5,680,123 disclosed three video cameras  82  to detect objects in the regions A, B, and C, and a display apparatus (not shown) installed in the tractor  801  to show the objects from regions A, B, and C by signal control switch (not shown). However, it is hard to install signal transmission lines and power transmission lines of the monitoring device on the vehicle  80 . 
     With the referenced to  FIG. 3 , the U.S. Pat. No. 6,995,687 disclosed a radio frequency transmission without wiring having an information provider  83  installed at the tractor  801 , and a detector installed at the container  802  to transmit non-wired image signals S 80 , S 83 , S 84 . However, interference problem of wireless transmission easily occurs in the car. 
     SUMMARY OF THE INVENTION 
     It is the main object of the present invention to provide a monitoring device of power line and camera to combine signal power line with signals and power for simplified wiring, easy installation and dismantling, being modular without affecting separation of tractor and container; such that the present invention ingrates single power line, signals and power supply. 
     In order to achieve the above object, the monitoring device of power line and camera mounted on a vehicle, comprises a cable line installed within the vehicle, and electrically connected to a power system of the vehicle to form a first power line; a first camera located at a periphery of the vehicle to capture a first image signal; a radio frequency transmitter having an input end electrically connected to the first camera and an output end electrically connected to the first power line, and the first image signal transmitted to the first power line by the radio frequency transmitter; a screen host located in the vehicle to display the first image signal; and a radio frequency receiver having an input end electrically connected to the first power line and an output end electrically connected to the screen host, and the first power line as a medium receiving the first image signal from the radio frequency transmitter and transmitting the signal to the screen host; whereby the first power line generates carrier wave for the first image signal as a radio frequency signal being transmitted to the wired cable line and then to the screen host. 
     Based on the features disclosed, the radio frequency transmitter is electrically connected to a second camera to capture a second image signal, and the second camera is embedded in a rearview mirror of the vehicle. The power line is electrically connected to a second power line, and the second power line is electrically connected to a driving video recorder. The driving video recorder is electrically connected to a third camera which captures a third image signal, and the third camera is arranged in a front end of the vehicle. 
     Further, the radio frequency transmitter has a first circuit module, and the first circuit module has a modulator, a first oscillator, a first operational amplifier, and a first capacitor; the first image signal or second image signal is modulated into high frequency signal by the modulator, transmitted to the first oscillator to produce periodic sinusoidal wave signal, and then amplified by the first operational amplifier to be transmitted to the first capacitor for signal coupling, and finally the signal is transmitted to the first power line. The first power line in parallel is electrically connected to a first pulse-width modulation and second pulse-width modulation to control voltage and supply power for the first camera or second camera, and the first circuit module. 
     Further, the radio frequency receiver has a second circuit module, and the second circuit module has a demodulator, a frequency mixer, a second oscillator, a surface filter, a second operational amplifier, a third operational amplifier, a forth operational amplifier, and a second capacitor; the high frequency signal is transmitted to the first power line and the second capacitor for signal coupling, amplified by the second operational amplifier, and then transmitted to the second oscillator to produce periodic sinusoidal wave signal; at the same time, the amplified signal and sinusoidal wave signal are mixed by the frequency mixer to form intermediate frequency signal; the signal is amplified by the third operational amplifier, transmitted to the surface filter for noise filtering, and then amplified by the forth operational amplifier to be transmitted to the demodulator for the intermediate frequency signal being demodulated into the first image signal or second image signal, and finally the signal is transmitted to the screen host. 
     Furthermore, the first power line in parallel is electrically connected to a third pulse-width modulation and forth pulse-width modulation to control voltage and supply power for the screen host, and the second circuit module. 
     The first power line further has a first cable connector and second cable connector. 
     Based on the features disclosed, the present invention combines the radio frequency transmitter and radio frequency receiver by the first power line to avoid noise interference and strengthen the stability of the device. Also, the combination of single power line, signals and power supply simplify wiring, and have easy installation and dismantling modular for integrating the power lines, power supply, and signals without affecting the separation of tractor and container. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of a conventional monitoring device of rearview mirror for vehicles; 
         FIG. 2  is a schematic view of a conventional camera monitoring device with cable transmission for vehicles; 
         FIG. 3  is a schematic view of a conventional camera monitoring device with wireless transmission for vehicles; 
         FIG. 4  is a schematic view of monitoring device of power line and camera in accordance with the present invention; 
         FIG. 5  is a circuit block view of monitoring device of power line and camera in accordance with the present invention; 
         FIG. 6  is a circuit block view of a radio frequency transmitter of the present invention; 
         FIG. 7  is a circuit block view of a radio frequency receiver of the present invention; 
         FIG. 8  is a schematic view of the present invention, showing a camera embedded in a rearview mirror; and 
         FIG. 9  is a schematic view of monitoring device of power line and camera in accordance with the present invention, the monitoring device detecting objects. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 4 and 5 , the preferred embodiment of a monitoring device of power line and camera mounted on a vehicle  10 , comprises a cable line  11  installed within the vehicle  10 , and electrically connected to a power system  12  of the vehicle  10  to form a first power line  13 . The first power line  13  has both ends respectively and electrically connected to a radio frequency transmitter  30  and a radio frequency receiver  50 . The first cable connector  70  and second cable connector  71  are arranged at a junction of the first power line  13  to separate a tractor  101  and container  102  of the vehicle  10  for reducing the correlation between the location of the radio frequency transmitter and radio frequency receiver  30 ,  50 , and enhancing independence. 
     The vehicle  10  has a screen host  40  and a first camera  20  respectively arranged at a front end and rear end thereof. The radio frequency transmitter  30  has an input end electrically connected to the first camera  20  and an output end electrically connected to the first power line  13 , and the radio frequency receiver  50  has an input end electrically connected to the first power line  13  and an output end electrically connected to the screen host  40  so that the first power line  13  supplies power for the radio frequency transmitter and radio frequency receiver  30 ,  50  for transmitting radio frequency signal  60 , and the first power line  13  also supplies power for the first camera and screen host  20 ,  40 . 
     In the embodiment, the first camera  20  takes a first object  22  to capture a first image signal  21 ; the radio frequency transmitter  30  is electrically connected to a second camera  23  to take a second object  25  and capture a second image signal  24 , and the second camera  23  is embedded in a rearview mirror  103  of the vehicle  10 . As a result, the radio frequency transmitter  30  transmits the first image signal or second image signal  21 ,  24  to the first power line  13 , and the first power line  13  as a medium receiving the first image signal  21  from the radio frequency transmitter  30  and transmitting the signal to the screen host  40 . 
     Corresponding to the above features, the power line  13  is electrically connected to a second power line  90 , and the second power line  90  is electrically connected to a driving video recorder  91 . The driving video recorder  91  is electrically connected to a third camera  92  which takes a third object  94  to capture a third image signal  93  for being transmitted to the screen host  40  and being recorded un the driving video recorder  91 . Further, the power line  13  is electrically connected to the second power line  90  for the first image signal or second image signal  21 ,  24  to be transmitted to the second power line  90 , and recorded to the driving video recorder  91 . 
     With the reference  FIG. 6 , the radio frequency transmitter  30  has a first circuit module  31 , and the first circuit module  31  has a modulator  311 , a first oscillator  312 , a first operational amplifier  313 , and a first capacitor  314 ; the first image signal or second image signal  21 ,  24  is modulated into high frequency signal  315  by the modulator  311 , transmitted to the first oscillator  312  to produce periodic sinusoidal wave signal, and then amplified by the first operational amplifier  313  to be transmitted to the first capacitor  314  for signal coupling  61 , and finally the signal is transmitted to the first power line  13 . 
     Further, the first power line  13  in parallel is electrically connected to a first pulse-width modulation  32  and second pulse-width modulation  33  to respectively send voltage of 5 volts (V) to the first circuit module  31 , and voltage of 12 volts (V) to the first camera  20  for controlling voltage and supplying power for the first camera  20  or the second camera  23 , and the first circuit module  31 . 
     With the reference  FIG. 7 , the radio frequency receiver  50  has a second circuit module  51 , and the second circuit module  51  has a demodulator  511 , a frequency mixer  512 , a second oscillator  513 , a surface filter  514 , a second operational amplifier  515 , a third operational amplifier  516 , a forth operational amplifier  517 , and a second capacitor  518 ; the high frequency signal  315  is transmitted to the first power line  13  and the second capacitor  518  for signal coupling, amplified by the second operational amplifier  515 , and then transmitted to the second oscillator  513  to produce periodic sinusoidal wave signal; at the same time, the amplified signal and sinusoidal wave signal are mixed by the frequency mixer  512  to form intermediate frequency signal  519 ; the signal is amplified by the third operational amplifier  516 , transmitted to the surface filter  514  for noise filtering, and then amplified by the forth operational amplifier  517  to be transmitted to the demodulator  511  for the intermediate frequency signal  519  being demodulated into the first image signal or second image signal  21 ,  24 , and finally the signal is transmitted to the screen host  40 . 
     Further, the first power line  13  in parallel is electrically connected to a third pulse-width modulation  52  and forth pulse-width modulation  53  to respectively send voltage of 5 volts (V) to the second circuit module  51 , and voltage of 12 volts (V) to the screen host  40  for controlling voltage and supplying power for the screen host  40  and the second circuit module  51 . 
     With the reference to  FIGS. 8 and 9 , the first camera  20 , second camera  23 , and third camera  92  is respectively arranged at the rear end of the vehicle  10 , embedded in a rearview mirror  103  of the vehicle  10 , and arranged at the front end of the vehicle  10  to form a monitoring region C right behind the vehicle  10 , monitoring regions A and B rearward extending from the right and left perspective view, and monitoring region D right in front of the vehicle  10 . The image signals  21 ,  24 ,  93  captured by the above cameras  20 ,  23 ,  92  can be recorded by the driving video recorder  91  for driver&#39;s accident record in order to clarify the attribution of liability. 
     Based on the features disclosed, the present invention integrates wireless signals, cable signals, and power to transmit image signals by power transmission. The present invention also provides single power line for each camera so that any of the cameras can be set at any position of the vehicle  10  to monitor the objects around the vehicle  10 . 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.

Technology Category: h