Power tool system and battery pack thereof

Abstract

A power tool system and a battery pack. The battery pack includes a housing provided with a socket, and two battery cell groups received in the housing. Each battery cell group has a positive electrode and a negative electrode. The socket has four conductive terminals respectively and electrically connected to the electrodes of two battery cell groups. Two battery cell groups can be switched between isolated state and series connected state to output two different voltages through two conductive terminals with different polarities being disconnected or connected to each other, and the two conductive terminals with different polarities are respectively connected to two battery cell groups.

We claim: 
     
         1 . A battery pack, comprising:
 a housing having a socket located thereon, the socket having a plurality of terminals received therein, the terminals including four conductive terminals; and   two battery cell groups received in the housing and each having a positive electrode and a negative electrode respectively and electrically connected to the corresponding conductive terminal of the socket;   wherein two battery cell groups can be switched between isolated state and series connected state to output two different voltages through two conductive terminals with different polarities being disconnected or connected to each other, and wherein the two conductive terminals with different polarities are respectively connected to two battery cell groups.   
     
     
         2 . The battery pack according to  claim 1 , wherein the two conductive terminals with different polarities are adjacent and separate to each other, and wherein two battery cell groups are isolated with each other in the battery pack and output a low voltage. 
     
     
         3 . The battery pack according to  claim 2 , wherein four conductive terminals are arranged adjacent to each other, and wherein the two conductive terminals with different polarities are located in the middle, and wherein two adjacent conductive terminals located on two sides have same polarity. 
     
     
         4 . The battery pack according to  claim 1 , wherein the two conductive terminals with different polarities are adjacent and connected to each other, and wherein two battery cell groups are connected with each other in series in the battery pack and output a high voltage. 
     
     
         5 . The battery pack according to  claim 4 , wherein four conductive terminals are arranged adjacent to each other, and wherein the two conductive terminals with different polarities are located in the middle, and wherein two adjacent conductive terminals located on two sides have same polarity. 
     
     
         6 . The battery pack according to  claim 2 , wherein four conductive terminals are arranged adjacent to each other, and wherein two conductive terminals with different polarities are located on one side of the four conductive terminals, and wherein two adjacent conductive terminals which are located in the middle have same polarity. 
     
     
         7 . The battery pack according to  claim 2 , wherein the two conductive terminals with different polarities each defines a contacting arm, and wherein the contacting arms of the two conductive terminals with different polarities are close but separate to each other. 
     
     
         8 . The battery pack according to  claim 7 , wherein two battery cell groups are switched from isolated state to series connected state to output a high voltage through changing the connection of two contacting arms from separate state to connected state. 
     
     
         9 . The battery pack according to  claim 7 , wherein two battery cell groups are in series connected state and output a high voltage when the contacting arms of the two conductive terminals are connected to each other. 
     
     
         10 . The battery pack according to  claim 4 , wherein the two conductive terminals with different polarities each defines a contacting arm, and wherein the contacting arms of the two conductive terminals with different polarities are directly connected to each other through two contacting arms abutting with each other. 
     
     
         11 . The battery pack according to  claim 9 , wherein two battery cell groups are switched from series connected state to isolated state to output a low voltage through changing the connection of two contacting arms from electrical connected state to electrical isolated state. 
     
     
         12 . The battery pack according to  claim 9 , wherein two battery cell groups are in isolated state and output a low voltage when the contacting arms of the two conductive terminals are isolated from each other. 
     
     
         13 . The battery pack according to  claim 10 , wherein the two conductive terminals with different polarities each further defines a pair of main arms located on one side of the contacting arm, and wherein the main arms are in idle state when the contacting arms of the two conductive terminals abutting with each other. 
     
     
         14 . A power tool system, comprising:
 a high rated-voltage power tool having a first male plug;   a low rated-voltage power tool having a second male plug; and   a battery pack supplying power to the high or low rated-voltage power tool connected thereto, including:
 a housing having a socket located thereon, the socket defining a plurality of terminals received therein, the terminals including four conductive terminals, and 
 two battery cell groups received in the housing and each defining a positive electrode and a negative electrode respectively and electrically connected to corresponding conductive terminal; 
   wherein two battery cell groups can be switched between isolated state and series connected state through two conductive terminals with different polarities being disconnected or connected to each other, and wherein the two conductive terminals with different polarities are respectively connected to two battery cell groups, and wherein the battery pack outputs a low voltage through connecting two battery cell groups in parallel when the second male plug is connected to the socket and a high voltage through connecting two battery cell groups in series when the first male plug is connected to the socket.   
     
     
         15 . The power tool system according to  claim 14 , wherein two conductive terminals with different polarities are adjacent and separate to each other, and wherein two battery cell groups are isolated with each other in the battery pack. 
     
     
         16 . The power tool system according to  claim 15 , wherein the second male plug has four contacting terminals corresponding to four conductive terminals of the battery pack, and wherein the four contacting terminals are respectively and electrically connected to corresponding four conductive terminals when two cell groups are connected with each other in parallel. 
     
     
         17 . The power tool system according to  claim 16 , wherein the first male plug has one connecting terminal simultaneously and electrically connected with the two conductive terminals with different polarities and two conducting terminals respectively connected with corresponding conductive terminal of another two conductive terminals of the socket, and wherein two battery cell groups are connected to each other in series through the connecting terminal simultaneously connecting one of the two conductive terminals with different polarities to the other of two conductive terminals with different polarities. 
     
     
         18 . The power tool system according to  claim 17 , wherein the connecting terminal of the first male plug is simultaneously and electrically connected to the two conductive terminals with different polarities through two opposite sides thereof. 
     
     
         19 . The power tool system according to  claim 14 , wherein the two conductive terminals with different polarities are adjacent and connected to each other, and wherein two battery cell groups are connected with each other in series in the battery pack. 
     
     
         20 . The power tool system according to  claim 19 , wherein the first male plug of the high rated-voltage power tool has two conducting terminals respectively and electrically connected to corresponding conductive terminals of the rest two conductive terminals in the four conductive terminals, and wherein the conductive terminals with different polarities are disengaged when the first male plug is assembled to the socket. 
     
     
         21 . The power tool system according to  claim 20 , wherein the second male plug of the low rated-voltage power tool has two contacting terminals and an insulating rib located in the middle of two contacting terminals, and wherein each contacting terminal defines a pair of contacting arms branched at the end thereof for connecting with corresponding conductive terminal of the socket, and wherein the insulating rib is inserted into the connected two conductive terminals of the socket to electrically isolate these two conductive terminals, and wherein two cell groups are connected with each other in parallel when the insulating rib of the second male plug is clamped by the two conductive terminals with different polarities. 
     
     
         22 . The power tool system according to  claim 21 , wherein four conductive terminals are arranged adjacent to each other, and wherein the two conductive terminals with different polarities are located in the middle, and wherein two adjacent conductive terminals located on two sides have same polarity. 
     
     
         23 . The power tool system according to  claim 18 , wherein four conductive terminals are arranged adjacent to each other, and wherein the two conductive terminals with different polarities are located in the middle, and wherein two adjacent conductive terminals located on two sides have same polarity. 
     
     
         24 . The power tool system according to  claim 18 , wherein four conductive terminals are arranged adjacent to each other, and wherein two conductive terminals with different polarities are located on one side of the four conductive terminals, and wherein two adjacent conductive terminals which are located in the middle have same polarity. 
     
     
         25 . The power tool system according to  claim 17 , wherein two conductive terminals with different polarities defines a gap formed therebetween, and wherein the connecting terminal is inserted into the gap for simultaneously and electrically connecting the two conductive terminals with different polarities together. 
     
     
         26 . The power tool system according to  claim 16 , wherein the second male plug has an insulating rib located in the middle of four contacting terminals, and wherein the insulating rib is inserted into two conductive terminals in the middle to electrically isolated these two conductive terminals.