Patent Publication Number: US-7589610-B2

Title: Over current cut-off switch

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates in general to a power switch, and more particularly to an over current cut-off switch. 
   2. Description of the Related Art 
   With reference to  FIGS. 4 and 5 , a conventional cut-off switch has a housing  50 , a first conductive foot  51 , a second conductive foot  52 , a reed  53 , a switch button  54  and a bump  55 . The housing  50  is of an electric insulating material. The first conductive foot  51  and the second conductive foot  52  are respectively configured inside the housing  50  penetrating a bottom of the housing  50 . The reed  53  is configured inside the housing  50 . One end of the reed  53  is riveted to a surface of the first conductive foot  51 , and the other free end of the reed  53  faces the second conductive foot  52 . 
   The switch button  54  is configured on a top of the housing  50 . One side of a bottom of the switch button  54  has the bump  55 . The bump  55  penetrates inside the housing  50  facing a top of the free end of the reed  53 . 
   When using the aforesaid cut-off switch, the switch button  54  is firstly pressed to make the bump  55  on the bottom of the switch button  54  press the reed  53  to contact the top of the second conductive foot  52  and then to be fixed. With reference to  FIG. 6 , when an over current flows through the cut-off switch, the reed  53  flips upward to make the first conductive foot  51  and the second conductive foot  52  disconnected. Moreover, when the reed  53  flips upward, the bump  55  above the reed  52  is also pushed to move upward, so as to switch a status of the switch button  54 . When users eliminate the over current status and want to recover the disconnection status, the users only need to press the switch button  54  again to make the bump  55  press the free end of the reed  53  downward to contact the second conductive foot  52 . 
   Although the aforesaid cut-off switch can be used repeatedly, in practical usage, the conventional cut-off device is often used under the over current status. Since the reed  53  and the first conductive foot  51  are riveted together, the reed  53  and the first conductive foot  51  are easily to become deformed due to a material feature. Hence a riveted point is easily to be broken and can not conduct electricity. 
   SUMMARY OF THE INVENTION 
   An objective of the present invention is to provide an over current cut-off switch. The present invention is aimed to effectively overcome the disadvantages of the conventional over current cut-off switch that the riveted point of the reed and the conductive foot is easily to be broken due to the over current. 
   In order to achieve the above objective, the over current cut-off switch is provided. 
   An over current cut-off switch has an electric insulating housing, a first conductive foot, a second conductive foot, a reed, an electric wire and a switch button. Upper portions of the first conductive foot and the second conductive foot are configured inside the electric insulating housing. Lower portions of the first conductive foot and the second conductive foot are penetrating outside the electric insulating housing for plugging to an external circuit. The reed has one end riveted to a surface of the first conductive foot and the other free end of the reed facing the second conductive foot. The electric wire is cross-connected to both sides of a riveted point of the reed and the first conductive foot. The switch button is configured on a top of the electric insulating housing. One side of a bottom of the switch button has a bump. The bump penetrates inside the electric insulating housing facing a top of the free end of the reed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a part of an over current cut-off switch in accordance with the present invention; 
       FIG. 2  is an operational side plan view of the part of the over current cut-off switch in accordance with the present invention; 
       FIG. 3  is another operational side plan view of the part of the over current cut-off switch in accordance with the present invention; 
       FIG. 4  is a perspective view of a part of a conventional over current cut-off switch in accordance with the prior art; 
       FIG. 5  is a side view of the conventional over current cut-off switch for the power supply in accordance with the prior art; and 
       FIG. 6  is an operational side plan view of the conventional over current cut-off switch for the power supply in accordance with the prior art. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   With reference to  FIGS. 1 and 2 , a preferred embodiment in accordance with the present invention is similar to the conventional over current cut-off switch; hence an introduction of the present invention focuses on structures of a reed  20  and two conductive feet  10  and  11 . An over current cut-off switch of the present invention has an electric insulating housing (not shown in the diagram), a first conductive foot  10 , a second conductive foot  11 , a reed  20 , an electric wire  21  and a connecting conductor  30 . 
   The electric insulating housing is of an electric insulating material. Upper portions of the first conductive foot  10  and the second conductive foot  11  are configured inside the electric insulating housing. On the other hand, lower portions of the first conductive foot  10  and the second conductive foot  11  are penetrating outside the electric insulating housing for plugging to an external circuit. The reed  20  is also inside the electric insulating housing  10  and has two ends. One free end of the reed  20  is separately connected to a top of the second conductive foot  11 . The connecting conductor is mounted between the other end of the reed  20  and the upper portion of the first conductive foot  10 . The reed  20  and the connecting conductor  30  are of a copper alloy sheet metal so they have resilience. 
   The electric wire  21  is mounted between the first conductive foot  10  and the reed  20 . Therefore, the electric wire is parallel with the connecting conductor  31 . The electric wire  21  may be a woven copper wire for high-amperage. In this preferred embodiment, the connecting conductor  30  has two ends. The two ends of the connecting conductor  30  are respectively to the top of the reed  20  and the outer surface of the first conductive foot  10 . The electric wire  21  has two ends respectively mounted between a bottom of the reed  20  and the inner surface of the first conductive foot  10 . 
   A switch button (not shown in the diagram) is configured on a top of the electric insulating housing. One side of a bottom of the switch button has a bump. The bump penetrates inside the electric insulating housing facing a top of the free end of the reed  20 . 
   With reference to  FIG. 2  and  FIG. 3 , operations of the over current cut-off switch of the present invention are introduced as follows. The free end of the reed  20  contacts the top of the second conductive foot  11  when an electric current of the power supply is normal. Once an over current flows from the first conductive foot  10  through the reed  20  to the second conductive foot  11 , a part of the current flows to the electric wire  21 , so as to branch the over current. In this way, the riveted point  30  can avoid breaking off due to the over current. 
   While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.