This invention relates in general to an electric circuit interrupt. More specifically, this invention relates to a manual disconnect for an electric battery manual disconnect.
Electric batteries are used to store and supply power for various types of machines. Batteries are often used to provide power to portable electronic equipment. Unlike a power source like a generator, which may be turned off, the battery may continue to supply power as long as there is a closed circuit between its terminals. Typically, when the electronic equipment is serviced, repaired, or inspected, the circuit is opened so that there is no current flow.
Electric vehicles and hybrid vehicles may use high voltage batteries to store electric power. This power can be provided to the vehicle by an external source, such as a wall outlet, or by an internal source such as a gasoline engine or regenerative brakes. The high voltage batteries may be used to provide power to vehicle systems such as electric drive motors that propel the vehicle. It is sometimes desirable to disconnect the high voltage batteries so that there is no high voltage current provided to any of the vehicle's systems. This can be done to avoid damage to the vehicle systems as well as to avoid injury to people. For example, in order to reduce the risk of electrocution, during service of the vehicle a technician may disconnect the battery, or after an accident a first responder may disconnect the battery. Consequently, vehicles that include high voltage batteries may include a manual disconnect, to allow the circuit including the high voltage batteries to be manually opened. It is desirable to have an improved manual disconnect.
This invention relates to a manual disconnect for an electric circuit. The manual disconnect includes a housing and a base attached to the housing by a fastener. The base includes primary terminals. The manual disconnect also includes a plug assembly that includes fuse terminals and a bolt cover. The plug assembly is movable relative to the base between a disconnected position wherein the fuse terminals are not engaged with respective primary terminals, and a primary circuit engaged position wherein the fuse terminals are engaged with respective primary terminals. When the plug assembly is in the primary circuit engaged position the bolt cover is positioned to prevent the fastener from being removed from the housing.
Various aspects of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.
Referring now to the drawings, there is illustrated in
The electric vehicle 10 includes a manual disconnect, indicated generally at 20. The manual disconnect 20 allows a technician to open the primary circuit 18 at the battery 12, for example, when the electric motor 14 is to be serviced. It should be appreciated that the primary circuit 18 is only described in a simplified form sufficient for the understanding of the manual disconnect 20. The preferred embodiment of the invention will be described in connection with the battery 12 on the electric vehicle 10, but it should be appreciated that the invention may be used as an electric disconnect in any desired circuit.
The manual disconnect 20 includes a base 24 that is mounted to the battery 12 and a plug assembly, indicated generally at 26. The plug assembly 26 may be moved relative to the base 24 between a connected position and a disconnected position. The plug assembly 26 includes a fuse 28. When the plug assembly 26 is in the connected position relative to the base 24, current flow through the primary circuit 18 passes through the fuse 28. When the plug assembly 26 is disconnected from the base 24, the primary circuit 18 is open.
The manual disconnect 20 also includes an interlock resistor 30. The interlock resistor 30 is part of an interlock loop, indicated generally at 32. The interlock loop 32 is an electric circuit that is closed when the plug assembly 26 is connected to the base 24, and is opened when the plug assembly 26 is disconnected from the base 24. A battery control 34 monitors the status of the interlock loop 32. If the interlock loop 32 is opened, the battery control 34 shuts down electric current flow through the primary circuit 18.
Referring now to
The plug assembly 26 includes a plug housing 36 and a handle 38. The illustrated plug housing 36 and the illustrated handle 38 are both molded from plastic, but may be made of any other desired materials. The handle 38 is connected to the plug housing 36 for relative rotational movement, as will be described below. Referring to
Referring back to
Referring to
As previously described in reference to
The process of connecting the plug assembly 26 to the base 24 will now be described in detail. As previously described, the plug assembly 26 includes the plug housing 36 and the handle 38.
The plug housing 36 also includes a pair of resilient stops, 74a and 74b, that extend from the plug housing surface 40. The illustrated resilient stops 74a and 74b are integrally molded with the plug housing surface 40, but may be made separately, if desired. The resilient stops 74a and 74b define respective V-shaped notches 78a and 78b. Referring to
The resilient stops 74a and 74b and the finger 80 are arranged so that as the handle 38 is rotated relative to the plug housing 36, the finger 80 will first engage one of the resilient stops 74a and 74b and deflect it. As the handle 38 is further rotated relative to the plug housing 36, the engaged resilient stop 74a and 74b will rebound and the finger 80 will be engaged within the respective notch 78a and 78b. To rotate the handle 38 further relative to the plug housing 36, the technician will have to apply sufficient force to deflect the resilient stop 74a and 74b. Thus, the technician will be able to feel when the finger 80 is engaged with the notches 78a and 78b. When the finger 80 is engaged with notch 78a, the handle 38 is in an insertion position relative to the plug housing 36. When the finger 80 is engaged with the notch 78b, the handle 38 is in a locked position relative to the plug housing 36. The significance of these two positions will be described below.
Referring back to
The illustrated plug assembly 26 includes two lock tabs 86a and 86b. However, the plug assembly 26 may include a different desired number of lock tabs 86a and 86b. The illustrated lock tabs 86a and 86b are integrally molded with and extend from the handle 38. However, the lock tabs 86a and 86b may be separate components, if desired. As best seen in
When the handle 38 is in the insertion position relative to the plug housing 36, the slot 84 is aligned with the projection 82, and the plug assembly 26 is moved in the insertion direction 56 relative to the base 24, the lock tabs 86a and 86b enter the respective lock channels 88a and 88b. A profile side view of the lock channel 88a is shown in
From the primary circuit engaged position, the handle 38 may be rotated about the rotation axis 72 in a locking direction 94. It should be appreciated that the handle 38 is rotated relative to both the plug housing 36 and the base 24, while the plug housing 36 remains stationary relative to the base 24. The handle 38 may be rotated relative to the base 24 until the lock tab 86a is in the location 96a. In the illustrated embodiment, in order to move from location 92a to location 96a the handle 38 is rotated 15 degrees. However, these locations may be positions any desired amount of rotation apart.
From location 96a, the handle 38 may be moved further in the insertion direction 56. It should be appreciated that the plug assembly 26, including both the handle 38 and the plug housing 36, move in the insertion direction 56 relative to the base 24 until the lock tab 86a is in the location 98a. At this point, the plug assembly 26 is in an interlock position relative to the base 24. The fuse terminals 44a and 44b remain engaged by the respective primary terminals 46a and 46b, and the primary circuit 18 remains closed. Additionally, the base interlock connector 58 is engaged with the interlock resistor assembly 60 to close the interlock loop 32. At this point, the battery control 34 will allow electric current to flow through the primary circuit 18.
From the interlock position, the handle 38 may be rotated about the rotation axis 72 in the locking direction 94. It should be appreciated that the handle 38 is rotated relative to both the plug housing 36 and the base 24, while the plug housing 36 remains stationary relative to the base 24. The handle 38 may be rotated relative to the base 24 until the lock tab 86a is in the location 100a. In the illustrated embodiment, in order to move from location 98a to location 100a, the handle 38 is rotated 15 degrees. However, these locations may be positions any desired amount of rotation apart.
When the lock tab 86a is in the location 100a, the handle 38 is in the locked position relative to the plug housing 36. As previously described, the finger 80 is engaged with the notch 78b. At this position, the plug assembly 26 is fully connected to the base 24, and both the primary circuit 18 and the interlock loop 32 remain closed.
The above-described process for connecting the plug assembly 26 to the base 24 described the interaction between the lock tab 86a and the lock channel 88a. It should be appreciated that the lock tab 86b has a similar interaction with the lock channel 88b.
The previously-described process for connecting the plug assembly 26 to the base 24 may be reversed to disconnect the plug assembly 26 from the base 24. As was described, during connection of the plug assembly 26 to the base 24, the primary circuit 18 is closed first and the interlock loop 32 closed second. It should be appreciated that during disconnection of the plug assembly 26 from the base 24, the interlock loop 32 is opened first and the primary circuit 18 is opened second.
Referring back to
The illustrated plug assembly 26 includes optional bolt covers 110. The illustrated bolt covers 110 are projections from the plug housing 36. The bolt covers 110 prevent the manual disconnect 20 from being removed from the battery 12 without first removing the plug assembly 26 from the base 24. Referring to
The principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.