DE10151163A1 - Device for charging batteries for electric vehicles switches charging current off when separating connection parts before electrical connection between power stage and vehicle is broken - Google Patents

Abstract

The device has a power stage and a connecting cable between the power stage and vehicle, a protection device for switching the charging current and a housing with a first connection part for connection to a second connection part on the cable. The connection parts interact with the protection device so the charging current is first switched off when separating the connection parts before the connection between power stage and vehicle is broken. The device has a power stage (38) and a connecting cable (6) for making an electrical connection between the power stage and the motor vehicle, a protection device (39) for switching the charging current on and off and a housing with a first connection part (5) for connection to a second connection part (8) on the connecting cable. The first and second connection parts interact with the protection device so that the charging current is first switched off when separating the connection parts before the electrical connection between the power stage and vehicle is broken.

Description

The batteries of the well-known electric vehicles are equipped with chargers charged, which are connected to a three-phase or alternating current network. she can not only at special charging stations, for example petrol stations, but can also be operated at home.

The known chargers have a power supply unit that connects one to the State of charge of the battery to be charged delivers charging current. in the In general, the chargers have a protective device for entry and exit Switching off the charging current in the event of a fault, for example in the event of an overload.

The electrical connection between the power supply and the electric vehicle is included a connecting cable is produced, which has a plug at its end, which is plugged into a suitable socket on the electric vehicle. The charger may only be switched on when the plug and socket are firmly connected are connected. Also, the electrical connection must not be disconnected, before the charger is switched off. Should the electrical connection is switched on or disconnected, is due to the high charging current will result in the formation of an arc, causing the Charger can be destroyed.

To prevent the formation of an arc with improper handling prevent the plug is mechanically firmly in the known chargers locked the socket of the vehicle. It cannot be excluded that the driver of the vehicle forgets to unlock the plug before driving off and pull out of the socket. It can also happen, for example, that the Driver releases the brake without paying attention to the connection when the vehicle stands on an inclined plane. This would not only have destroyed the mechanical locking of the plug in the socket, but also formation of an arc.

The invention is therefore based on the object of a device for charging of batteries for electric vehicles to create, even when improper Handling is protected from damage. In particular, the formation of Arcs are prevented and the cable-side connector is protected.

This object is achieved with the features of patent claim 1. Advantageous embodiments are the subject of the dependent claims.

For example, if the driver releases the brake when the vehicle is on a road is inclined without the connection between the loading device and Paying attention to the vehicle becomes the connection between the charging device and the vehicle separated in that the cable-side connecting part of the connecting cable from the housing-side connection part of the charging device is withdrawn without that the connection mechanically damages the charger or the Plug connection of the vehicle could be destroyed.

When removing the cable-side connector from the housing side Connection part prevents the formation of an arc by first the charging current is switched off before the electrical connection between Power supply and vehicle is separated, d. H. when disconnecting the electrical Connection no longer has charging current flowing.

In a preferred embodiment of the loading device, the formation of a Arc also when connecting the housing and cable-side connector excluded, because first the electrical connection between the power supply and Vehicle battery is manufactured before the charging current is switched on.

The cable-side connector is a particularly preferred one Embodiment from the normal position with respect to its longitudinal axis pivotally attached to the housing. As a result, the connecting parts and the connection cable in the event of a sudden tensile load in the direction of pull relieved. Since the connecting parts pivot in the resulting direction of pull, can be separated without exposing the parts to unacceptable forces are. The housing-side connection part is preferably in the normal position spring-loaded. The pivoting of the connector has independent of switching off the charging current to prevent arcing own inventive meaning.

In addition, the cable-side connector part of an elastic ring be enclosed, the plug when opening the connector Protects damage. The connecting parts preferably include both Power as well as communication contacts that when connecting the Contact connecting parts with each other. The flows through the power contacts Charging current while the communication contacts regulating the Communication between the battery management and the control of the Charger serve.

In a further particularly preferred embodiment, the Protection device a switching device that switches the charging current on and off (Network protection). The switching device (mains protection) switches on the charging current, when a control current flows through the corresponding communication contacts. The switching device, however, switches off the charging current if none Control current flows through the contacts.

The connection parts are preferably designed such that the contact between the corresponding communication contacts when disconnecting the Disconnect first before contact between the Power contacts is separated. Accordingly, the contact between the Power contacts when connecting the connecting parts first made before the contact between the communication contacts is established. Thereby is sure to be one when you connect and disconnect Prevents arcing.

The power and communication contacts are preferably different educated. The only thing that is decisive is that first one and then the other Contacts are separated or made. The power and communication contacts of pins and sockets for receiving the pins formed, the power level a longer length and preferably one have a larger diameter than the communication pins. When connecting the Connection parts are thus only the contact between the power pins and the power jacks made before communication pins and jacks to contact. This creates a structurally simple but safe device created. In addition to the service and communication contacts preferably also ground contacts, d. H. one grounding socket and one Earthing pin present, preferably before the power contacts contact or open after the service contacts.

Basically, the connecting parts can have a large number of outgoing and return lines as well as control lines. The connector on the housing side is preferably a connector, while the cable-side connector there is a suitable plug in the socket. The plug is preferably snapped into the socket, the plug in the socket one have a secure hold and only when there is a strong tensile load from the socket is extractable.

An embodiment of the invention is described below with reference to FIG the drawings explained in more detail.

Show it:

Fig. 1 shows a battery charging device in plan view,

Fig. 2, the battery charging apparatus from the view of the arrow I of Fig. 1,

Fig. 3 shows the first and second connecting part in a sectional view and

Fig. 4 shows the circuit diagram with the essential components of the charging device in a highly simplified representation.

The components of the charging device accommodate a housing 1 , which can be hung on a wall. The housing 1 has a housing lower part 2 through which cooling air flows. The cooling air enters the lower housing part from below at a lower ventilation slot 3 and exits from lateral and upper ventilation slots 4 on the long sides of the lower housing part from above.

On the underside of the lower housing part, a socket 5 is provided in the center for connecting a connecting cable 6 , with which the charging device is connected to the electric vehicle. Also located on the underside of the housing is the outlet for the mains cable 7 for connecting the charger to a three-phase network with three phases.

The connecting cable 6 has at one end a housing-side connector 8 , which can be plugged into the socket 5 , and at its other end a vehicle-side plug 9 , which can be plugged into a socket, not shown, of the vehicle. The vehicle-side connector 9 has a locking mechanism 10 with which the connector can be locked firmly in the socket of the vehicle. The locking takes place by pivoting the lever 11 .

On one long side of the lower housing part 2 , a holder 12 is provided for the vehicle-side connector 9 of the connecting cable 6 , in which the connector can be locked when the charging device is not in operation. The holder 12 for the plug 9 is a socket which corresponds to the socket of the vehicle.

On the lower housing part 2 there is a hermetically sealed upper housing part 13 , which receives the components of the charging device that are to be particularly protected from environmental influences. A control panel 14 with a display is located on the housing cover 15 .

Fig. 3 shows a sectional view of the socket 5 and the housing-side connector 8 of the connecting cable 6 , the connector and socket being connected to one another.

The bushing 5 has a substantially hemispherical central part 16 , which is adjoined by a substantially cylindrical front part 17 . The plug 8 has a base part 18 which merges into a likewise cylindrical front part 19 . When the plug 8 is inserted into the socket 5 , the front part 19 of the plug fits in the front part 17 of the socket. In an undercut ring groove 20 of the plug front part 19 , an O-ring 21 is cast, which snaps into a corresponding ring groove 22 on the socket front part 17 , so that the plug is securely fixed in the socket. An additional O-ring 23 , which sits in the gap between the plug front part 19 and the socket middle part 16 , serves for further sealing and the shock protection.

The hemispherical receptacle center part of metal 16 is mounted in the in Fig. 3 for better clarity, not shown, the housing lower part 3 (Fig. 2) is pivotally mounted. In the center of the lower housing part 3 , the socket middle part 16 is fastened to a central bolt 25 . The middle part 16 has a tapered cylindrical recess 26 which merges into a cast-in ball socket 27 , while the screwed-on bolt 25 has a spherical head 28 which is seated in the spherical recess 27 . In its normal position on the longitudinal axis of the bushing 5 , the bolt 25 is aligned vertically by a spiral spring 29 which is supported on the one hand on the central part 16 and on the other hand on a shoulder of the bolt 25 . The middle part 16 is sealed off from the lower housing part 3 by a seal with sealing lips 30 .

If the connecting cable 6 is not under tension, the bolt 25 is in the vertical starting position shown in solid lines in FIG. 3. The bolt is deflected into the position shown in dashed lines only in the case of tensile loads, so that the socket 5 is pivoted to relieve all plug connections, ie also the plug connections on the vehicle, and the connecting cable.

The connecting cable 6 has power conductors 31 and an earth conductor (not shown) in which the charging current or short-circuit current flows, and communication conductors 32 in which control currents are transmitted.

Two socket-shaped power contacts 33 and ground contacts (not shown) and a plurality of communication contacts 34 arranged circumferentially distributed are cast in casting resin in the middle part 16 of the socket. The power conductors 31 leading into the interior of the housing and ground conductors (not shown) are connected to the power contacts 33 , while the communication conductors 32 are connected to the communication contacts 34 . The connections are made using screw connections, which are also encapsulated with casting resin, so that the contact sockets are internally free of arcing points.

In the plug front part 19 , a plate 35 is inserted, to which pin-shaped power contacts 36 and communication contacts 37 are fastened with tolerance clearance, which engage in the corresponding power and communication sockets 33 , 34 of the ISO socket 5 when the plug and socket are connected to one another. The power or grounding and communication conductors 31 , 32 of the connecting cable are connected to the power or grounding and communication pins 36 , 37 by means of screw connections.

The grounding and power pins 36 embedded in insulating material to avoid leakage currents have a greater length and a larger diameter than the communication pins 37 of the plug 8 , so that when the plug and socket are connected, the electrical contact between the grounding and power pins and sockets first 36 , 33 is established before the communication pins 37 and sockets 34 contact.

The base part 18 of the plug 8 is enclosed by an elastic ring 41 which protects the plug against impact if the plug should hit the ground with its outside.

FIG. 4 shows an electrical circuit diagram with the essential components of the charging device, the parts which correspond to those of FIGS. 1 to 3 being provided with the same reference numbers.

The charging device has a power supply unit 38 which is connected to the three phases of the three-phase network via the mains cable 7 with the conductors L _{1, 2, 3} . The power supply unit 38 supplies a charging current that is adapted to the respective state of charge of the vehicle battery to be charged. The electrical connection between the power supply unit and the battery is established with the connecting cable 6 .

Two power conductors 31 , 31 '(forward and return conductors) and an earth conductor (not shown) lead from the power supply 38 to the socket 5 . Forward and return conductors 31 , 31 'are connected to the contact sockets 33 , 33 '.

To switch the charging current on and off, a protective device 39 is provided, from which two communication lines 32 , 32 'extend, which are connected to the communication sockets 34 , 34 ' of the socket S. When the communication lines 32 , 32 'are short-circuited, ie a control current flows, the protective device 39 generates a control signal which a switching device 40 receives. The switching device 40 then immediately switches off the charging current flowing through the forward and return conductors 31 , 31 '. The connector 8 has power pins 36 , 36 'for the forward and return conductors 31 , 31 ' of the connecting cable 6 and a grounding pin, not shown, which are connected to the vehicle-side connector 9 , which is inserted into the battery charging socket 39 of the vehicle. The two communication pins 37 , 37 'of the plug 8 are short-circuited, so that a control current flows through the contacts when the plug 8 is seated in the socket 5 .

In the event that the plug 8 is accidentally torn out of the socket 5 , the contact between the communication pins and sockets is disconnected first, so that the charging current is switched off by the switching device 40 before the contact between the power pins and sockets or Earthing pin and socket is disconnected. This effectively prevents the formation of an arc. On the other hand, when connecting plug 8 and socket 5 , the contact between the power pins and socket or grounding pin and socket is made before the communication pins and socket contact, so that the switching device 40 only switches on the charging current when the grounding and electrical Connection between power supply and vehicle battery is established. This effectively prevents the formation of an arc even when the plug and socket are connected.

Claims (13)

1. Device for charging batteries for electric vehicles with
a power supply unit ( 38 ) and a connecting cable ( 6 ) for establishing an electrical connection between the power supply unit and the motor vehicle,
a protective device ( 39 ) for switching the charging current on and off, and
a housing ( 1 ) that houses the power supply and protective device,
characterized in that the housing ( 1 ) has a first connecting part ( 5 ) and the connecting cable ( 6 ) has a second connecting part ( 8 ) to be connected to the first connecting part ( 5 ) for connecting the connecting cable ( 6 ) to the housing, the the first and second connection parts cooperate with the protective device ( 39 ) in such a way that when the first and second connection parts are disconnected, the charging current is first switched off before the electrical connection between the power pack and the motor vehicle is disconnected. 2. Device according to claim 1, characterized in that the first and second connection part ( 5 , 8 ) cooperate with the protective device ( 39 ) in such a way that when connecting the first and second connection part, an electrical connection is first established between the power supply unit ( 38 ) and the motor vehicle before the charging current is switched on. 3. Apparatus according to claim 1 or 2, characterized in that the first connection part ( 5 ) from a normal position relative to the longitudinal axis is pivotally attached to the housing ( 1 ). 4. The device according to claim 3, characterized in that the first connecting part ( 5 ) is resiliently biased into the normal position. 5. Device according to one of claims 1 to 4, characterized in that the second connection part ( 8 ) is enclosed by an elastic ring ( 41 ). 6. Device according to one of claims 1 to 5, characterized in that the first and second connecting part ( 5 , 8 ) each have corresponding power contacts ( 33 , 36 ) and communication contacts ( 34 , 37 ) which contact each other when connecting the connecting parts. 7. The device according to claim 6, characterized in that the protective device ( 39 ) has a switching device ( 40 ) which switches the charging current on and off, which switches on the charging current when the corresponding communication contacts ( 34 , 37 ) contact and switches off the charging current, if the communication contacts do not contact. 8. The device according to claim 7, characterized in that the contact between the corresponding communication contacts ( 34 , 37 ) of the first and second connection parts ( 5 , 8 ) is separated when the connection parts are disconnected before the contact between the power contacts ( 33 , 36 ) is separated. 9. The device according to claim 7 or 8, characterized in that the contact between the corresponding power contacts ( 33 , 36 ) of the first and second connection part ( 5 , 8 ) is made when connecting the connection parts first, before the contact between the communication contacts ( 34 , 37 ) is produced. 10. Device according to one of claims 6 to 9, characterized in that the power and communication contacts of the first connection part ( 5 ) power or communication sockets ( 33 , 34 ) and the power and communication contacts of the second connection part ( 8 ) power and communication pins ( 36 , 37 ), the power pins ( 36 ) being longer in length than the communication pins ( 37 ). 11. The device according to claim 10, characterized in that the power and communication pins ( 36 , 37 ) and power and communication sockets ( 33 , 34 ) are arranged around the longitudinal axis of the first and second connecting part ( 5 , 8 ). 12. Device according to one of claims 1 to 11, characterized in that the first and second connecting part ( 5 , 8 ) can be locked in place. 13. Device according to one of claims 1 to 12, characterized in that the first connection part is a connection socket ( 5 ) and the second connection part is a connection plug ( 8 ) which fits into the socket.