Abstract:
The present invention is directed to a motor vehicle battery having an internal terminal disconnect switch for selectively preventing current flow from a motor vehicle battery, wherein the disconnect switch comprises a housing enclosing the contact point between an external terminal of the battery and its corresponding internal terminal, wherein the housing comprises a plurality of seals for isolating the internal environment of the housing from the environment external to said housing.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to a motor vehicle battery having a disconnect switch. 
         [0003]    2. Description of Related Art 
         [0004]    Motor vehicle batteries are known to discharge upon storage, thereby requiring recharging or replacement following storage for an extended time. In addition, motor vehicle batteries sometimes produce an explosion when a load is connected to the battery terminal. Battery disconnect switches are a known solution to the former problem. The present invention addresses both the former problem and the latter problem. 
         [0005]    U.S. Pat. No. 6,744,344 discloses a disconnect switch for the load circuit of a vehicle battery which includes a movable contact element and a stationary contact element that are linked with a locking mechanism. For releasing the locking mechanism a shape-memory alloy release element is used that contracts when heated. For closing the locking mechanism a shape-memory alloy spring element is provided that induces closure of the mechanism by expansion. 
         [0006]    U.S. Pat. No. 6,492,745 discloses a battery control system for controlling the connection of a plurality of batteries to a load. The system comprises a plurality of switches and a plurality of controllers. Each switch is operable to connect or disconnect one of the batteries from the load. Each controller is operatively coupled to one of the switches. Each controller is operative to cause one of the switches to disconnect one of the batteries from the load. Each controller has an input and an output for communicating with another controller wherein the controllers communicate with each other to limit the number of batteries that can be disconnected from the loads. 
         [0007]    U.S. Pat. No. 6,049,140 discloses a manually reversible battery disconnection system for mounting directly on a terminal of a battery of a motor vehicle. The system includes a housing; a battery terminal connector secured to the housing; a normally closed electrical switch mounted inside the housing; an electrical conductor connected to the battery terminal connector and to one side of the switch; one or more fuses mounted inside the housing, and connected between the other side of the switch and output terminals mounted on the housing; a sensor for detecting an adverse condition; an electromagnetically operated device mounted inside the housing and electrically connected to the sensor, mechanically connected to the switch, and actuable on receipt of an adverse condition signal from the sensor to open the switch; and a manual control mounted on the housing and mechanically connected to the switch for manually operating the switch. 
         [0008]    However, the aforementioned battery disconnect switches do not provide a sealed environment for establishing or preventing the point of contact with the battery terminal. 
         [0009]    Thus, there exists a need for a motor vehicle battery containing an internal terminal disconnect switch that provides a sealed, and therefore safe, contact point with the battery terminal. The present invention substantially fulfills this need. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention is directed to a motor vehicle battery comprising an internal terminal disconnect switch for selectively preventing current flow from said motor vehicle battery, said internal terminal disconnect switch comprising: (a) a housing enclosing the contact point between an external terminal of said battery and a corresponding internal terminal, said housing comprising a plurality of seals for isolating the internal environment of said housing from the environment external to said housing; and (b) means for moving said external terminal of said battery relative to its corresponding internal terminal within said housing, wherein contacting said external terminal to said internal terminal permits current flow from the battery, and wherein moving said external terminal away from said internal terminal to a position in which said external terminal and said internal terminal are not in contact with each other prevents current flow from the battery. In another embodiment, the present invention provides a motor vehicle battery comprising an internal terminal disconnect switch for selectively preventing current flow from said motor vehicle battery, said internal terminal disconnect switch comprising: (a) a housing enclosing the contact point between an external terminal of said battery and a corresponding internal terminal, said housing comprising a plurality of seals for isolating the internal environment of said housing from the environment external to said housing; and (b) means for moving said internal terminal of said battery relative to its corresponding external terminal within said housing, wherein contacting said internal terminal to said external terminal permits current flow from the battery, and wherein moving said internal terminal away from said external terminal to a position in which said internal terminal and said external terminal are not in contact with each other prevents current flow from the battery. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein: 
           [0012]      FIG. 1  is a cross-sectional view of an embodiment of the present invention. 
           [0013]      FIG. 2  is a cross-sectional view of an embodiment of the present invention in which the internal terminal disconnect switch includes a spring which facilitates movement of the batter external terminal relative to its corresponding internal terminal. 
           [0014]      FIG. 3  is a cross-sectional view of an embodiment of the present invention in which the internal terminal disconnect switch operates by moving the position of the internal terminal relative to the external terminal. 
           [0015]      FIG. 4  is a cross-sectional view of an embodiment of the present invention. 
       
    
    
       [0016]    In the following description of the invention similar reference characters refer to similar parts throughout the several views of the drawings. 
       DETAILED DESCRIPTION 
       [0017]      FIG. 1  show motor vehicle battery  5  having an external housing  10 , electrolyte solution  20 , cell plates  30 , internal terminal disconnect switch housing  40 , internal terminal  50 , seals  60 , external terminal  70 , manual control  80 , sealed environment  90 , opposite terminal  100  and vent cap  110 . In operation, manual control  80  is mechanically connected to external terminal  70  and allows a user to push external terminal  70  down so as to contact internal terminal  50 , thereby allowing current to flow from motor vehicle battery  5  to an external load (not shown). Seals  60  may be affixed to housing  40 , external terminal  70  and/or internal terminal  50 . As shown, the point of contact between external terminal  70  and internal terminal  50  occurs in a sealed environment  90 . 
         [0018]    Alternatively, when motor vehicle battery  5  is to be stored for an extended period of time, manual control  80  allows a user to pull external terminal  70  up so as to not contact internal terminal  50 , thereby preventing motor vehicle battery  5  from discharging over time. In addition, when it is desired to connect an external load to battery  5  under enhanced safety conditions, manual control  80  allows a user to pull external terminal  70  up to a position where it does not contact internal terminal  50 , thereby allowing a user to connect an external load to external terminal  70  and then push external terminal  70  down to contact internal terminal  50 . This sequence of events completes the electrical circuit within sealed environment  90  rather than in an open, oxygen rich environment. 
         [0019]      FIG. 2  show motor vehicle battery  5  having an external housing  10 , electrolyte solution  20 , cell plates  30 , internal terminal disconnect switch housing  40 , internal terminal  50 , seals  60 , external terminal  70 , manual control  80 , sealed environment  90 , opposite terminal  100 , vent cap  110  and spring  120 . Spring  120  is affixed to housing  40 . In operation, spring  120  facilitates vertical movement of external terminal  70  along a vertical axis relative to the internal terminal  50 .  FIG. 3  shows an alternative embodiment of the present invention, in which manual control  80  is mechanically connected to internal terminal  50  and thereby allows a user to push internal terminal  50  down to a position where it does not contact external terminal  70 , thereby allowing a user to connect an external load to external terminal  70  and then pull internal terminal  50  up to contact external terminal  70 . This sequence of events completes the electrical circuit within sealed environment  90  rather than in an open, oxygen rich environment. 
         [0020]      FIG. 3  also shows electrically conductive, flexible connector  120  linking internal terminal  50  to cell plates  30 . Electrically conductive, flexible connector  120  allows internal terminal  50  to move freely between an open position, where internal terminal  50  and external terminal  70  are not in contact, and a closed position, in which internal terminal  50  and external terminal  70  are in contact, while maintaining a continuous connection with cell plates  30 . 
         [0021]      FIG. 4  shows an alternative embodiment of the present invention, in which the contact surfaces of external terminal  70  and internal terminal  50  are designed such that by using manual control  80  to rotate external terminal  70  relative to internal terminal  50  a user can easily toggle the internal terminal disconnect switch between an open position, in which external terminal  70  and internal terminal  50  are not in contact with each other, and a closed position, in which external terminal  70  and internal terminal  50  are in contact with each other. As shown, the point of contact between external terminal  70  and internal terminal  50  occurs in a sealed environment  90 . Of course, although shown in  FIG. 4 , it is equally possible to mechanically connect manual control  80  to internal terminal  50 , thereby permitting a user to toggle the internal terminal disconnect switch between an open position (shown) and a closed position (not shown) by rotating internal terminal  50  relative to external terminal  70 . 
         [0022]    While particular embodiments of the present invention have been shown and described herein for purposes of illustration, it will be understood that the invention is not limited thereto. Modifications may be made by persons skilled in the art, particularly in light of the foregoing teachings, without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. 
         [0023]    All of the U.S. patents and published U.S. patent applications referred to in this specification are incorporated herein by reference in their entirety to the extent not inconsistent with the present description.