POWER SUPPLY PROTECTIVE DEVICE FOR CARS

This power supply protective device for cars can be used to protect electric appliances when they are connected to cars. Such a protective device can protect expensive electric appliances used in cars such as laptop computers. When these appliances are in use, they make use of the extended power supply from the cigar-lighter base in cars. This invention can protect such a power supply source. The invention uses a simple inserting/connecting structure to wrap the thin lock-piece fuse inside and then insert it into the cigar-lighter base. Moreover, it is very easy to change fuses.

SYMBOLS FOR MAJOR PARTS 1 Inserting section 11 Circuit board 12 Linking section 121 ˜ 123 Inserting grooves 124 , 125 Electrode connecting pieces 2 Thin lock-piece fuse 3 Extended part 31 , 32 Linking pieces 311 , 312 Groove holes 33 Inserting groove 4 Extension cord 5 Electric appliances 6 Cigar-lighter base in cars 
 DETAILED DESCRIPTIONS OF THE PREFERRED EMBODIMENT Please refer to FIG. 1 . The power supply protective device of cars mentioned in this invention includes the following major parts. First, there is an inserting section ( 1 ). The front end of the inserting section ( 1 ) can be inserted into the cigar-lighter base in cars. Then, the power will go through the circuit board ( 11 ), thin lock-piece fuse ( 2 ) and extended part ( 3 ) and finally be connected to electric appliances through the extension cord ( 4 ). Then, the back end of the above-mentioned inserting section ( 1 ) has a linking section ( 12 ). Inside the linking section ( 12 ) are inserting grooves ( 121 , 122 & 123 ), positive and negative electrode connecting pieces ( 124 & 125 ). When they are connected to the extended part ( 3 ), the whole structure is completed. Insert the thin lock-piece fuse ( 2 ) into the inserting groove ( 123 ) in inserting section ( 1 ) to protect electric appliances. Next, there is an extended part ( 3 ). Its front end has linking blocks ( 31 & 32 ) corresponding to the linking section ( 12 ). The linking block has groove holes ( 311 & 312 ) and they can direct the power supply that comes in from the inserting section ( 1 ) to come out from the extension cord ( 4 ). Then, the power can be used by electric appliances used in the car. The extension cord ( 4 ) can be connected to different types of plugs according to the users'needs. In the central part of the extension cord, there is an inserting groove ( 33 ) to be used to fix the position of the fuse. Please refer to FIG. 2 . The cutaway diagram shows that the linking section ( 12 ) located in the back end of the inserting section ( 1 ) has several inserting grooves ( 121 , 122 & 123 ). On both sides of inserting grooves 121 , 122 & 123 , there are electrode connecting pieces ( 124 & 125 ). These two pieces are connected to an embedded circuit board ( 13 ). The thin lock-piece fuse ( 2 ) is inserted into the inserting groove 123 located in the middle for power to go through. Please also refer to FIG. 3 . The power supply inside the car is connected to connecting points a and b. When the thin lock-piece fuse ( 2 ) is inserted, connecting points b and c will immediately be connected and power supply from both positive and negative electrodes will go from connecting points a and c to the connecting pieces 124 and 125 . In addition, groove holes ( 311 & 312 ) on the linking blocks ( 31 & 32 ) at the front end of the extended part ( 3 ) have metallic contact inside. Such a contact can direct power to the back end of the extension cord through electrode connecting pieces ( 124 & 125 ). Then, this set-up can be used for all kinds of electric appliances. Inserting groove 33 is used to fix the position of the thin lock-piece fuse ( 2 ). Please refer to FIG. 4 . When passengers use electric appliances ( 5 ) in their cars, they can obtain power supply from the cigar-lighter base ( 6 ). With the protection of this invention, users do not have to worry about possible damages or breakdown and can concentrate on their own work. This invention of the power supply protective device for cars has following advantages compared with the traditional models. 1. It is very small and easy to carry. Moreover, it is very easy to find a space for its storage. 2. The power cord can be extended unlimitedly. When users go outdoors for picnic, they can extend the cord beyond the car and make its use more diverse. In other words, such power supply becomes portable. Many changes and modifications in the above-described embodiment of the invention can, of course, be carried out without departing from the scope thereof. Accordingly, to promote the progress in science and the useful arts, the invention is disclosed and is intended to be limited only by the scope of the appended claims.