Abstract:
An on-vehicle power supply device is connected to a vehicle battery with revealing. The on-vehicle power supply device is used for receiving a DC input power supplied by the vehicle battery, and the on-vehicle power supply device induces a plurality of high-frequency voltages through a single isolation transformer at the same time, and then transforms the high-frequency voltages to produce at least one AC output voltage and DC output voltage. In addition, the on-vehicle power supply device further includes a rechargeable battery. The rechargeable battery can be charged when the DC input power is importing. When the DC input power stops importing, the rechargeable battery is used for supplying a backup power to the isolation transformer, and the rechargeable battery keeps producing AC output voltage and DC output voltage. Hence, the present invention can achieve the effects of multipurpose, safety, and continuity.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the invention 
         [0002]    The present invention relates to a power supply device, and more particularly to an on-vehicle power supply device. 
         [0003]    2. Description of Related Art 
         [0004]    In recent years, technological industries are developed rapidly, and electronic technologies are integrated and applied extensively in many different fields to gain competitive edges and values. As to the automobile industry, more and more automobile electronics are applied and integrated into cars each year. For example, LED related products, multimedia A/V products, monitoring devices and global positioning systems (GPS) are installed in cars. Of course, many technologies also modify their designs to support more on-vehicle electronic products, and thus this business opportunity obviously becomes one of the key factors for the development of electronics in the future. 
         [0005]    To integrate or support the electronic peripheral devices, designers and manufacturers need to solve the issue of the on-vehicle power supply first. Since users generally obtain electric power directly from the DC power of a car battery through a cigarette lighter in a car or the AC power output (with a voltage of 110V/220V similar to that of the utility power) obtained through converting the power of the car battery by the so-called car inverter. If a user intends to use a DC electronic peripheral device through the car inverter in a car, the user needs to use an AC/DC adapter originally bundled with the DC electronic peripheral device, but such application is inconvenient and occupies space in the car. 
         [0006]    In addition, the main issue of the prior art resides on that users cannot obtain a power supply continuously, since the car battery supplies electric power to users only when the car engine is turned on. If the car engine is turned off, the users no longer can obtain the electric power of car battery from the cigarette lighter or converted by the car inverter. As a result, the users cannot continue using the electronic peripheral device. 
         [0007]    Finding a feasible solution for the on-vehicle power supply and providing users different voltages by a multipurpose, safe and continuous method demand further researches and improvements. 
       SUMMARY OF THE INVENTION 
       [0008]    In view of the foregoing shortcoming of the prior art, the inventor of the present invention intended to simultaneously supply AC and DC power isolated from a car battery through a simple and reduced circuit design, so that an output power can isolate noises produced by a car battery when the car battery is charged, and design a plurality of DC power outputs for a flexible application. In the meantime, the present invention further designs a rechargeable battery which is charged when the car supplies electric power, and automatically forms a power supply to allow users to maintain a continuous use of an electronic peripheral device when the car does not supply electric power, so as to achieve the effects of multipurpose, safety, and continuity. 
         [0009]    To achieve the foregoing objective, the present invention provides an on-vehicle power supply device connected to a vehicle battery, and the on-vehicle power supply device comprises: a first switch module, a rechargeable battery, a second switch module, a power controller, an isolation transformer, at least one first output unit and at least one second output unit. The first switch module is used for receiving a DC input power supplied by the vehicle battery and converting the DC input power into a first high-frequency power, and the second switch module is a two-way switch module for charging battery or converting the DC input power of the battery into a second high-frequency power. The power controller detects the DC input power to control the operations of the first switch module and the second switch module, so that only one of the first high-frequency power and the second high-frequency power outputs power at a time. The isolation transformer is electrically connected to the first switch module and the second switch module for receiving the first high-frequency power or the second high-frequency power respectively, so as to couple to the outputs of a plurality of high-frequency voltages. Finally, the first output unit and the second output unit are electrically connected to the isolation transformer for receiving a high-frequency voltage and converting the high-frequency voltage to separately output an AC output voltage and a DC output voltage. If the power controller detects an input of the DC input power, then the power controller will control the first switch module to operate and convert the DC input power into a first high-frequency power, and also controls the second switch module to switch into a charging state. If the power controller detects a stop of inputting the DC input power, then the power controller will stop controlling the first switch module and will control the second switch module to switch to a power supplying state to generate a high-frequency power. 
         [0010]    To make it easier for our examiner to understand the innovative features and technical content, we use the following preferred embodiments together with related drawings for the detailed description of the invention, and it should be pointed out that the attached drawings are provided for reference and description only, but not for limiting the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a block diagram of an on-vehicle power supply in accordance with a preferred embodiment of the present invention; 
           [0012]      FIG. 2  is a schematic circuit diagram of an on-vehicle power supply device in accordance with the present invention; and 
           [0013]      FIG. 3  is a schematic view of an application of an on-vehicle power supply device in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0014]    Referring to  FIGS. 1 and 2  for a block diagram and a schematic circuit diagram of an on-vehicle power supply device in accordance with the present invention, the on-vehicle power supply device  1  is installed to a vehicle by an exposing method and connected to a vehicle battery (not shown in the figure) for supplying DC power and AC power to users in a car through various designs of electric power outputs. 
         [0015]    The on-vehicle power supply device  1  of the invention comprises: a power controller  10 , a first switch module  11 , a second switch module  12 , a rechargeable battery  13 , an isolation transformer  14 , at least one first output unit  15 , at least one second output unit  16 , a filter  17 , at least one AC power socket  18  and at least one DC power socket  19 . The rechargeable battery  13  is mainly used for storing and supplying a backup power. In other words, the on-vehicle power supply device  1  not only obtains a DC input power  100  from the vehicle battery, but also obtains a backup power in the rechargeable battery  13 , and thus the invention can convert a power supply anytime to supply the require power to users appropriately. 
         [0016]    To avoid being influenced at the instant moment of starting a car engine while the on-vehicle power supply device  1  is receiving the DC input power  100  supplied by vehicle battery, manufacturers need to suppress the noises by means of a filter  17 , so that a power controller  10  and a first switch module  11  electrically connected to the filter  17  can obtain a cleaner DC input power  100 . 
         [0017]    When the first switch module  11  receives the DC input power  100 , the power controller  10  switches and controls a transistor Q 1  and a transistor Q 2  in the first switch module  11  to convert the DC input power  100  into a first high-frequency power  101 . The first switch module  11  can be designed as a push-pull circuit as shown in  FIG. 2  or a half-bridge or full-bridge circuit. 
         [0018]    In actual design, the second switch module  12  is a two-way switch module electrically connected to the power controller  10  and the rechargeable battery  13 , so that when the backup power is outputted from the rechargeable battery  13 , the power controller  10  is switched and controlled to convert the backup power into a second high-frequency power  102 . In addition to the function of receiving the second high-frequency power  102  switched and controlled by the power controller  10 , the second switch module  12  is also used for charging the rechargeable battery  13  or serving as a switch for discharging the rechargeable battery  13 . The way for the power controller  10  to control the charge or discharge of the rechargeable battery  13  will be described as follows. 
         [0019]    In a design of the power controller  10 , the power controller  10  detects whether or not the DC input power  100  is inputted to control the operations of the first switch module  11  and the second switch module  12 , such that only one of the first high-frequency power  101  and the second high-frequency power  102  outputs power at a time. If the power controller  10  detects an input of DC input power  100  to the vehicle battery, the power controller  10  controls the first switch module  11  to switch the operation to convert the first high-frequency power  101  normally, and also controls the second switch module  12  to switch into a state of charging rechargeable battery  13 . Now, the second switch module  12  will not generate an output of second high-frequency power  102 , but will simply receive the DC input power  100  to charge the rechargeable battery  13 . If the power controller  10  detects a stop of inputting the DC input power  100 , then the power controller  10  will stop controlling the first switch module  11 , and will control the second switch module  12  to switch to a state of receiving a backup power of the rechargeable battery  13 , so as to control the second switch module  12  to switch to a power supplying state to operate and convert to a second high-frequency power  102 . 
         [0020]    Referring to  FIG. 2  for a schematic circuit diagram of a second switch module  12  of an on-vehicle power supply device in accordance with the present invention, the second switch module  12  performs a two-way control in this embodiment. If the power controller  10  detects an input of the AC input power  100 , then the power controller  10  will control a transistor Q 3  and a transistor Q 4  to stop the operation and electrically conduct a diode D 1  and a diode D 3  to drive the second switch module  12  to a state of charging the rechargeable battery  13 . On the other hand, if the power controller  10  detects a stop of inputting DC input power  100 , then the power controller  10  will control the transistor Q 3  and the transistor Q 4  to perform the operation and stop conducting the diode D 1  and the diode D 2 , and thus the second switch module  12  will be situated at a state of receiving the backup power of the rechargeable battery  13  to convert to a second high-frequency power  102 . 
         [0021]    In addition, the isolation transformer  14  is electrically connected to the first switch module  11  and the second switch module  12  for receiving the first high-frequency power  101  or second high-frequency power  102  to perform an induction to generate a plurality of high-frequency voltages  103 . Since the isolation transformer  14  adopts the design of a multi-winding isolation transformer, therefore the isolation transformer  14  can generate a plurality of high-frequency voltages  103  for different applications. 
         [0022]    The first output unit  15  and the second output unit  16  are electrically connected to the isolation transformer  14 , so that the quantity of output units in a practical application design depends on the number of high-frequency voltages  103  that can be generated by the isolation transformer  14 , but the present invention has no particular limitation on the quantity of output units. The first output unit  15  further comprises a rectifier  151  and a converter  152 , wherein the rectifier  151  is used for rectifying the current of the high-frequency voltage  103  to convert to a temporary DC voltage  104 , and the converter  152  is a DC/AC converter electrically connected to the rectifier  151  for converting the temporary DC voltage  104  into an AC output voltage  105  with a frequency equal to that of utility power. The second output unit  16  further comprises a rectifier  161  and a voltage regulator  162 , wherein the rectifier  161  is used for rectifying the current of a high-frequency voltage  103  received by the second output unit  16  to convert to the temporary DC voltage  104 , and the voltage regulator  162  is a DC/DC voltage regulator electrically connected to the rectifier  161  for regulating the temporary DC voltage  104  to a DC output voltage  106 . 
         [0023]    The first output unit  15  is electrically connected to an AC power socket  18  for outputting the AC output voltage  105  to an AC electronic device (not shown in the figure). Similarly, the second output unit  16  is electrically connected to a DC power socket  19  for outputting the DC output voltage  106  to a DC electronic device (not shown in the figure). Therefore, when a user uses the on-vehicle power supply device  1 , the user can receive a power supply regardless of whether or not the car is operated at a power supplying state, and thus the user can continue using the electronic device. In addition, the on-vehicle power supply device  1  is connected and exposed, and thus the user can have the required power supply anytime and anywhere. 
         [0024]    Referring to  FIG. 3  for a schematic view of an application of an on-vehicle power supply device in accordance with the present invention, the on-vehicle power supply device  1  is connected to a cigarette lighter  3  in a car through a cigarette lighter cable  2 , and the on-vehicle power supply device  1  provides an AC power socket  18  for connecting an AC electronic device  4  (such as a small fan) as well as a DC power socket  19  designed with a fixed DC socket  1901  and a cable connecting DC plug  1902 , wherein the difference between the fixed DC socket  1901  and the cable connecting DC plug  1902  resides on that the fixed DC socket  1901  is fixed onto a casing of the on-vehicle power supply device  1 , and the cable connecting DC plug  1902  is extended out of the casing of the on-vehicle power supply device  1  through an extension cord. In addition, the fixed DC socket  1901  and the cable connecting DC plug  1902  can be designed as a universal serial bus jack (USB jack) and/or a direct current jack to facilitate users to connect an appropriate DC electronic device  5  (such as a personal digital assistant or a notebook computer). With the design of the cable connecting DC plug  1902 , the present invention allows passengers at the backseats of the car to obtain power easily. It is noteworthy to point out that the cable connecting DC plug  1902  can be an attachable DC plug for connecting various plugs of different sizes and specifications to fit a DC electronic device  5  having various plugs of different sizes (such as notebook computers of different brands). 
         [0025]    In summation of the description above, the on-vehicle power supply device of the present invention can achieve the purpose of supplying power to users regardless of whether or not a car is in a state of supplying power. In addition, the invention provides a DC power output and comes with a design to fit different DC power plugs, so that users in a car can waive the inconvenient use of an AC/DC adapter for the DC electronic device when the DC electronic device is used, and achieve the advantageous effect of saving space in a car. 
         [0026]    Although the present invention has been described with reference to the preferred embodiments and related drawings thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.