Patent Publication Number: US-9845017-B2

Title: Charging apparatus for a vehicle

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of PCT International Application No. PCT/EP2012/067817, filed Sep. 12, 2012, which claims priority under 35 U.S.C. §119 from German Patent Application No. 10 2011 082 896.6, filed Sep. 16, 2011, the entire disclosures of which are herein expressly incorporated by reference. 
     This application contains related subject matter to U.S. patent application Ser. No. 14/212,248, filed on even date herewith, entitled “Charging Apparatus for a Vehicle with Seven Electrical Contacts.” 
    
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
     The invention relates to a charging apparatus for a vehicle having an energy accumulator (energy store), the charging apparatus comprising a charging source, a charging plug, a charging socket, a charging control device, an alternating-current (AC) charging device and a power switching device. The charging socket has nine electrically assignable contacts, the first contact being connected as a pilot contact by way of a pilot line with the charging control device, the second contact being connected as proxy contact by way of a proximity line with the charging control device, the third contact being connected as a protective grounding conductor by way of a ground line with the vehicle ground, the fourth contact being connected as a neutral conductor contact by way of a neutral line with the alternating-current charging device, and the fifth contact being connected as a phase 1 contact by way of a phase 1 line with the alternating-current charging device. 
     World-wide, vehicles with an electrified drive train are considered the key to the individual mobility of the future. Modern vehicle development is working on solutions for charging a vehicle-internal accumulator for the electric traction energy. Wired decentralized charging methods are currently being favored. This means that a surface-related density of external charging sources for the vehicle is available to the driver, where the average range of the vehicle corresponds at least to the average distance between two charging sources. A high charging comfort is distinguished by a high charging rate, i.e. brief charging periods, and by a high availability of charging sources for the vehicle; i.e. by high compatibility of the external charging sources with the vehicle. 
     According to the state of the art, a vehicle-side charging socket for a wired charging plug is being established; see, for example, the International Draft Standard IEC 62196. The 7-pole plug, called Type 2 in this Draft Standard 62196, offers the user the possibility of charging the battery of the vehicle with alternating current by way of the 1-phase alternating-current network or 3-phase alternating-current network and/or with direct current (DC) if the charging source makes these two charging types available. In this case, for charging with direct current, the power is limited to a current intensity of maximally approximately 80 A with a voltage of maximally 300 V-480 V. If a charging source provides for charging with direct current up to a current density of maximally 200 A and a voltage of maximally 600 V-850 V thereby permitting a faster charging, then according to Draft Standard IEC 62196, a plug-socket system called Combo-2 is used which has special direct-current contacts. 
     If a vehicle is equipped with a charging socket for the Type 2 plug, the user cannot charge the accumulator with a charging direct current of more than 80 A at a charging source having a Combo 2 plug. 
     It is an object of the invention to provide an improved charging apparatus for the electric charging of an energy accumulator of a vehicle. 
     This and other objects are achieved by a charging apparatus for a vehicle having an energy accumulator, the charging apparatus comprising a charging source, a charging plug, a charging socket, a charging control device, an alternating-current charging device and a power switching device. The charging socket comprises nine electrically assignable contacts. The first contact is connected as a pilot contact by way of a pilot line with the charging control device. The second contact is connected as proximity contact by way of a proxy line (proxy) with the charging control device. The third contact is connected as a protective grounding conductor contact by way of a ground line with the vehicle ground. The fourth contact is connected as a neutral conductor contact by way of a neutral line with the alternating-current charging device. The fifth contact is connected as a phase 1 contact by way of a phase 1 line with the alternating-current charging device. The eighth contact is connectable as a positive direct-current contact by way of a DC plus line and by way of the power separating device with the energy accumulator. The ninth contact is connectable as a negative direct-current contact by way of a DC minus line and by way of the power separating device with the energy accumulator. The sixth contact is connected as a phase 2 contact by way of a phase 2 line with the DC minus line. The seventh contact is connected as a phase 3 contact by way of a phase 3 line with the DC plus line. 
     According to the invention, the eighth contact is connected as a positive direct-current contact by way of a DC plus line and by way of the power switching device with the energy accumulator; the ninth contact is connected as a negative direct-current contact by way of a DC minus line and by way of the power switching device with the energy accumulator. Furthermore, according to the invention, the sixth contact is connected as a phase-2 contact by way of a phase-2 line with the DC minus line, and the seventh contact is connected as a phase-3 contact with the DC plus line. 
     This has the advantage that an external direct voltage situated between the sixth contact and the seventh contact is also applied between the DC minus line and the DC plus line 1. 
     According to a preferred embodiment of the invention, the charging socket has a protective cap operable by the charging control device or by the operator, by which protective cap, an opened position can be taken up, and by which a closed position can be taken up. In the closed position, the DC plus contact and the DC minus contact are covered. 
     The protective cap results in the special advantage that the DC plus contact and the DC minus contact can be covered, so that, within the scope of usage according to the regulations of the charging device, for the operator, these two contacts will not be freely accessible when the protective cap is closed. 
     According to a further variant of the present invention, the charging socket has a cap sensor by which the position of the protective cap can be detected. Furthermore, according to this variant, the invention includes a data connection between the cap sensor and the charging control device, by way of which data connection, the detected position of the protective cap can be transmitted to the charging control device by the cap sensor. 
     By way of the cap sensor, the protective cap can be recognized as being in a defined position. If required, the protective cap can be adjusted into the other position by the charging control device. As an alternative, a false position of the protective cap can be indicated to the operator. 
     Preferably, a first charging plug in the form of a plug-and-socket connection can be attached to the charging socket when the protective cap is open or when the protective cap is closed, which first charging plug is constructed with at least 3 poles and not more than 7 poles. At least three core poles of the first charging plug are electrically assigned, in the case of a plug-socket connection established by means of the first charging plug, the first three contacts being connected with the same assignments with the core poles of the first charging plug, and the not more than 7 poles being connected with the same assignments with the first seven contacts of the socket. When the plug-socket connection is established with the first charging plug, the protective cap can be closed or is closed. 
     With respect to its basic geometrical shape, the first charging plug may, for example, be constructed as a plug of Type 2, according to the International Draft Standard IEC 62196, and the charging socket of the vehicle, with respect to its geometrical design, may be constructed as a charging socket of the Combo-2 type. The core poles of the charging plug are the poles of the plug which, when the plug-socket connection is established in accordance with the regulations, are electrically contacted with the pilot contact, the proxy contact and the grounding conductor contact. With respect to its basic geometrical shape, the first charging plug may also be constructed as a plug of Type 1, according to the International Draft Standard IEC 62196. This plug has five poles which, with the same assignments, can be connected with the first five contacts of the socket. Assignment equality means that, when a plug-socket connection is established according to the regulations, a predetermined first pole of the plug is connected with the first contact of the socket; a predetermined second pole of the plug is connected with the second contact of the socket; a predetermined third pole of the plug is connected with the third contact of the socket; a predetermined fourth pole of the plug is connected with the fourth contact of the socket; and a predetermined fifth pole of the plug is connected with the fifth contact of the socket. Every electric pole of the plug is therefore electrically connected with a predetermined contact of the nine contacts of the charging socket. A connection of the same assignments can therefore, for example, be ensured by a mechanical guidance of the plug in the charging socket by means of projections, noses or bars. 
     According to a further embodiment of the invention, when the plug-socket connection is established with the first charging plug, and in the case of an electric assignment of the fourth contact and of the fifth contact with alternating voltage from the charging source, the battery can be charged by way of the alternating-current charging device. 
     This means that the user of the charging device can connect the vehicle with a charging source, which provides 1-phase alternating current, for charging the energy accumulator by way of the first charging plug. 
     As an alternative, when the plug-socket connection is established with the first charging plug and in the case of an electric assignment of the sixth contact and of the seventh contact with direct current from the charging source, the battery can be charged with direct current when the power connection is established by the power switching device and the protective cap is closed. 
     If, according to the Draft Standard IEC 62196, the first charging plug is constructed as a Type 2 plug and the charging socket is constructed as Combo-2, the charging source provides direct current, and the user connects the vehicle with the charging source by way of the first charging plug, the energy accumulator can be charged with direct current when the protective cap is closed. According to the Draft Standard IEC 62196, the direct current for charging with direct current for the Type 2 plug is limited to maximally 80 A. This type of charging is called DC low charging. It is a prerequisite for DC low charging with the Type 2 plug that the charging control device can detect that the protective cap is in the closed position, so that the positive direct-current contact and the negative direct-current contact cannot be touched in a freely accessible manner from the outside. 
     If the charging source can provide 1-phase alternating current as well as direct current, the charging control device can select and implement one of the two types of charging based on various parameters of the energy accumulator and of the charging source. A selected charging operation is controlled, or automatically controlled, according to the state of the art by the charging control device. 
     According to a further embodiment of the invention, a second charging plug in the form of a plug-socket connection can be attached to the charging socket when the protective cap is open. According to this embodiment, the second charging plug is constructed with at least three poles and not more than nine poles, in which case at least three core poles of the second charging plug are electrically assigned. When the plug-socket connection is established with the second charging plug, the first three contacts are connected with the same assignments with the core poles of the second charging plug, and the not more than nine poles are connected with the same assignments with the nine contacts of the socket. 
     With respect to their basic geometrical shape, the second charging plug and the charging socket can, for example, be constructed as a Combo-2 plug and a Combo-2 charging socket according to the International Draft Standard IEC 62196. The core poles of the charging plug are the poles of the plug which, if the plug-socket connection is established in accordance with the regulations, are electrically contacted with the pilot contact, the proxy contact and the grounding conductor contact. The further six contacts of the socket are contacted with the same assignments with maximally six further poles of the plug, i.e. predetermined poles of the plug may be present for certain further contacts of the socket. 
     Preferably, when the plug-socket connection is established with the second charging plug and with the electric assignment of the eighth contact and of the ninth contact with direct voltage by the charging source, the battery can be charged when the power connection is established by the power switching device. 
     If the charging source provides direct current for charging, when the plug-socket connection is established with the second charging plug, the energy accumulator can also be charged with direct current at a current intensity of more than 80 A. This type of charging is called DC high charging. DC high charging can also be carried out by way of the eighth contact and the ninth contact with a 7-pole Combo-1 plug according to the International Draft Standard IEC 62196. 
     In addition, when the plug-socket connection is established with the second charging plug and in the case of an electric assignment of the fourth contact and of the fifth contact with alternating voltage from the charging source, the battery can be charged by way of the alternating-voltage charging device. 
     This means that, with the second charging plug, the energy accumulator can also be charged with alternating current if the charging source provides 1-phase alternating voltage. If the charging source, while the plug-socket connection is established with the second charging plug, 1-phase alternating current as well as direct current can be provided for DC high charging, one charging type is selected and implemented by the charging control device based on various parameters of the energy accumulator and of the charging source. A selected charging operation is controlled, or automatically controlled, according to the state of the art by the charging control device. 
     The charging apparatus has the advantage that, by way of two different plugs, a plug-socket connection and thereby a charging connection can be established between the vehicle and the charging source. The user of the vehicle can establish a charging connection independently of the type of charging supported by the charging source (alternating current, DC low, DC high) and the used plug (Type 2 or Combo-2). As a function of the charging type supported by the charging source (alternating current, DC low, DC high) and the used plug (Type 2 or Combo-2), the charging control device can carry out that charging operation that is suitable on the basis of different existing influencing variables. 
     The invention is based on the considerations described in the following. For electric and hybrid vehicles, different conductive, i.e. wired, charging technologies exist at an external charging source. One of these wired charging variants is AC charging, i.e. alternating-current charging, in which case the charging apparatus is situated in the vehicle. Another wired charging variant is DC charging, i.e. direct-current charging, in which case the charging device is situated in the external charging station. DC charging is frequently also called rapid charging because the charging capacity is normally above that of the AC charging. 
     The international plug Draft Standard IEC 62196 describes a novel plug-socket system that is also called a Combo plug system. It thereby becomes possible to connect a plug, which permits an AC charging, to a single vehicle charging socket. A plug permitting DC charging can also be connected to this vehicle charging socket. A vehicle having such a charging topology on the basis of the Combo plug system can charge at an AC charging station as well as also at a DC charging station, the vehicle having only one installed charging connection. 
     The combo plug system comprises a charging socket and a charging plug. The charging socket is mounted at the vehicle. The charging plug, also called a coupler, is fixedly connected by way of the charging cable with the charging station during DC charging. 
     Draft Standard IEC 62196 describes different plug-socket variants. This relates, for example, to a plug that is called Type 2 and to a plug that is called Combo 2. As a function of the charging source, the vehicle with the Type 2 plug can be charged with direct current, the plug being designed for a charging current of up to 80 A. This charging variant is called DC low charging. By means of a plug of the Type 2 Combo plug, the vehicle can be charged with direct current, the plug being designed for a charging current of up to 200 A. This charging variant is called DC high charging. For this purpose, the Type 2 Combo plug has two poles designed for a high current load capacity, which are also called DC high poles. The further poles of the Type 2 Combo plug are called core poles. By means of both plugs, the vehicle can also be charged with alternating current depending on the charging station. 
     Independently of the plug to be attached to the vehicle (according to the IEC 62196, for example, a Type 2 plug, a Type 1 Combo plug or a Type 2 Combo plug), the vehicle has a charging architecture which includes an AC charging device, a communication unit and a DC protective contactor system for the power switching. The AC charging device is required exclusively for the AC charging. The DC protective contactor system ensures that no dangerous voltage is present at the charging socket. It needs to be ensured for reasons of safety that no high voltage is present on parts that may be touched, such as, for example, stand-alone exposed contacts of the charging socket. 
     According to the state of the art, a spreading of different external charging possibilities for the vehicle is becoming apparent, which permit a charging according to different charging variants. This has the disadvantage that a complex charging architecture has to be present in the vehicle which permits the charging of as many charging variants as possible. 
     The charging architecture should particularly permit DC low charging and DC high charging and be compatible with the Type 2 plug and the Type 2 Combo plug. 
     An improved charging architecture is therefore provided which has a charging socket for a Type 2 Combo plug. DC high charging is thereby made possible. Since the charging socket for the Type 2 Combo plug is compatible with the Type 2 plug, DC low charging can also be made possible with the provided charging socket. In the charging socket, the pins intended for the DC low charging are electrically connected with the pins for the DC high charging pertaining to the DC high poles. The charging socket therefore has a detectable protective cap by which the pins of the charging socket pertaining to the DC high poles can be covered. This ensures that, during the DC low charging, the pins pertaining to the DC high poles will not be freely accessible so as to be touchable from the outside. In this manner, no separate protections are required for the pins intended for the DC low charging. When using the Type 2 Combo plug, the cap will be open; when using the Type 2 plug, the cap will preferably be closed. 
     Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of a charging apparatus having a maximally 7-pole charging plug suitable for DC low charging (state of the art); 
         FIG. 2  is a schematic view of a charging apparatus having a maximally 9-pole charging plug suitable for DC high charging (state of the art); 
         FIG. 3  is a schematic view of a charging apparatus having a maximally 9-pole charging plug and having a protective cap, DC low charging, while the protective cap is closed; 
         FIG. 4  is a schematic view of a charging apparatus having a maximally 9-pole charging plug and having a protective cap, DC high charging, while the protective cap is open. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a charging arrangement according to the state of the art for an energy accumulator  1  of a vehicle. A charging source  2   a  is situated outside the vehicle. Depending on the type of construction and configuration of the charging source, the charging source provides an alternating current, which may be 1-phased or 3-phased, and/or direct current, for charging the energy accumulator. The charging source may, for example, be constructed as a public charging station or as a wall box installed in the vehicle user&#39;s home area. 
     The vehicle has a charging socket  4   a  which is usually integrated in the area of the body shell of the vehicle and can optionally be made accessible from the outside by way of a cover cap similar to a common fuel filler cap. 
     In addition, the vehicle has a charging control device  5   a , a charging device  6 , which is represented in  FIG. 1  as a 1-phase alternating-current charging device, and a contactor box  7  with two contactors for power switching or separation. For the power switching and separation, a MOSFET circuit can be also used as an alternative, in order to, if required, electrically separate the energy accumulator  1  from the charging device  6  or link it to the latter. Without limiting the generality, it will be assumed in the following that contactor switching is used. 
     In  FIG. 1 , the charging socket  4   a  of the vehicle has seven electric contacts. The first electric contact  11  is connected by way of a pilot line (pilot) with the charging control device and is called a pilot contact. The second electric contact  12  is connected by way of a proximity line (proxy) with the charging control device and is called a proximity contact. The third electric contact  13  is connected by way of a ground line (PE, protective earth) with the vehicle ground and is called a ground contact. The fourth electric contact  14  is implemented as a neutral conductor contact and is connected by way of a neutral line (N) with the AC charging device. The fifth electric contact  15  is designed as a phase contact and is connected by way of a phase line (L 1 ) with the AC charging device. The sixth electric contact  16  is designed as a phase contact and is connected by way of a phase line (L 2 ) with one of the two contactors of the contactor box. The seventh electric contact  17  is also designed as a phase contact and is connected by way of a phase line (L 3 ) with that contactor of the two contactors of the contactor box  7  that is not connected with the phase line (L 2 ). 
     A charging plug  3   a  can be connected to the charging socket. The charging plug is connected with the charging source  2   a  by way of a cable. The charging plug has maximally seven poles. In this case, it should be taken into account that, according to the state of the art, not necessarily every pole of the charging plug also has to be electrically assigned. As a result, a charging plug may, for example, be used which has a 7-pole construction and, in this case, has five assigned electric poles, i.e. five electric poles. The two unassigned poles may be made of a conductive or non-conductive material or at best may be implemented as briefly indicated. 
     An exclusive plug-socket connection with the same assignment can be established between the charging plug and the charging socket. This means that, in the case of an established plug-socket connection with the same assignments, which can also be called a charging connection, every electric pole of the plug can be electrically connected with a predetermined electric contact of the seven contacts of the charging socket. 
     Current charging plugs have at least three electric poles which, in the case of a charging connection, are connected with the pilot contact, the proximity contact and the grounding contact. 
     By way of the proximity contact, the charging connection and the charging plug can be identified by the charging control device  6  and an immobilizer of the vehicle can, for example, be activated. 
     In the case of a charging connection, the pilot line permits a communication between the charging control device and the charging source and the control or automatic control of a charging operation. 
     For example, in the case of a charging connection with a 1-phase alternating current present between the fourth contact and the fifth contact, the energy accumulator can be charged by way of the AC charging device  6 . This type of charging is called alternating-current charging. In this case the contactors of the contactor box  7  are open. 
     When the charging source provides direct current by way of the phase contact (L 2 ) and the phase contact (L 3 ), the energy accumulator can be charged with direct current. In this case, the contactors are closed by the charging control device  6 . 
     The plug-socket connection of the charging apparatus described in  FIG. 1  is sufficient for the Type 2 plug of the International Draft Standard IEC 62196 for the wired charging of electric vehicles. The direct-current charging therefore becomes possible up to a current of 80 A and a voltage of up to 300V-480 V. This type of direct-current charging is called DC low charging. 
       FIG. 2  illustrates a charging apparatus according to the state of the art for an energy accumulator  1  of a vehicle. A charging source  2   b  is situated outside the vehicle. Depending on the type of construction and configuration of the charging source, the charging source provides 1-phase alternating current and/or direct current, which may be 1-phased or three-phased, and/or direct current, for charging the energy accumulator. The charging source may, for example, be constructed as a public charging station or as a wall box installed in the vehicle user&#39;s home area. 
     The vehicle has a charging socket ( 4   b ) which is usually integrated in the area of the body shell of the vehicle and can optionally be made accessible from the outside by way of a cover cap similar to a common fuel filler cap. 
     In addition, the vehicle has a charging control device  5   b , a charging device  6 , which is represented in  FIG. 1  as a 1-phase alternating-current charging device, and a contactor box  7  with two contactors. 
     In  FIG. 2 , the charging socket of the vehicle has nine contacts, of which two contacts are electrically unassigned, i.e. no electric effect can be achieved by means of these contacts. The first electric contact  11  is connected by way of a pilot line (pilot) with the charging control device and is called a pilot contact. The second electric contact  12  is connected by way of a proximity line (proxy) with the charging control device and is called a proximity contact. The third electric contact  13  is connected by way of a ground line (PE, protective earth) with the vehicle ground and is called a ground contact. The fourth electric contact  14  is implemented as a neutral conductor contact and is connected by way of a neutral line (N) with the charging device. The fifth electric contact  15  is designed as a phase contact and is connected by way of a phase line (L 1 ) with the charging device  6 . The sixth contact  16 ′ and the seventh contact  17 ′ are unoccupied. The eighth electric contact  18  is connected by way of a direct-current line (DC+) with one of the two contactors of the contactor box and is called a positive direct-current contact. The ninth electric contact ( 19 ) is connected by way of a direct-current line (DC−) with that contactor of the two contactors of the contactor box which is not connected with the direct-current line (DC+) The ninth contact is called a negative direct-current contact. 
     A charging plug  3   b  can be connected to the charging socket. The charging plug is connected with the charging source by a cable. The charging plug has maximally nine poles. Attention should be paid to the fact that according to the state of the art not necessarily every pole of the charging plug also has to be electrically assigned. Accordingly, for example, a charging plug can be used which is constructed with 9 poles and in this case has five assigned poles, i.e. five electrically active poles. The four unassigned poles may be made of a conductive or non-conductive material or at best may be implemented as briefly indicated. 
     As in  FIG. 1 , an exclusive plug-socket connection with the same assignments can also be established in  FIG. 2  between the charging plug and the charging socket. This means that, in the case of a charging connection, each electric pole of the plug is electrically connected with a predetermined contact of the nine contacts of the charging socket. 
     Current charging plugs have at least three electric poles which, in the case of a charging connection, are connected with the pilot contact, the proximity contact and the ground contact. 
     The functions of the pilot contact and the proximity contact are as explained in  FIG. 1 . 
     For example, in  FIG. 2 , in the case of a charging connection with a 1-phase alternating current present between the fourth contact and the fifth contact, the energy accumulator can be charged by way of the AC charging device  6  while the contactors are open. 
     When the charging source provides direct current by way of the positive direct-current contact and the negative direct-current contact, the energy accumulator can be charged with direct current while the contactors are closed. 
     The plug-socket connection of the charging device described in  FIG. 2  is sufficient for the Combo-2 plug of the International Draft Standard IEC 62196 for the wired charging of electric vehicles. The direct-current charging is therefore possible up to a current of 200 A and a voltage of up to 600V-850 V. In this document, this type of direct-current charging is called DC high charging and permits a faster charging of the energy accumulator in comparison to DC low charging. 
       FIGS. 3 and 4  show an implemented example of the invention. A charging apparatus is described for an energy accumulator  1  of a vehicle. 
     A charging source ( 2   a  or  2   b ) is situated outside the vehicle. Depending on the type of construction and configuration of the charging source, the charging source provides an alternating current, which may be 1-phased or 3-phased, and/or direct current, for charging the energy accumulator. The charging source may, for example, be constructed as a public charging station or as a wall box installed in the vehicle user&#39;s home area. 
     The vehicle has a charging socket  4   c  which is usually integrated in the area of the body shell of the vehicle and can optionally be made accessible from the outside by way of a cover cap similar to a common fuel filler cap. 
     In addition, the vehicle has a charging control device  5   c , a charging device  6 , which is represented in  FIGS. 3 and 4  as a 1-phase or 3-phase alternating-current charging device, and a contactor box  7  with two contactors. 
     In  FIGS. 3 and 4 , the charging socket of the vehicle has nine electric assigned contacts. The first electric contact  11  is connected by way of a pilot line (pilot) with the charging control device  5   c  and is called a pilot contact. The second electric contact  12  is connected by way of a proximity line (proxy) with the charging control device  5   c  and is called a proximity contact. The third electric contact  13  is connected by way of a ground line (PE, protective earth) with the vehicle ground and is called a ground contact. The fourth electric contact  14  is implemented as a neutral conductor contact and is connected by way of a neutral line (N) with the charging device  6 . The fifth electric contact  15  is designed as a phase contact and is connected by way of a phase line (L 1 ) with the charging device  6 . The eighth electric contact  18  is connected by way of a direct-current line (DC+) with one of the two contactors of the contactor box and is called a positive direct-current contact. The ninth electric contact  19  is connected by way of a direct-current line (DC−) with that contactor of the two contactors of the contactor box which is not connected with the direct-current line (DC+) The ninth contact is called a negative direct-current contact. 
     The sixth contact ( 16 ″) is called a phase-2-contact and is short-circuited by way of an electric line (L 2 ″) with the negative direct-current contact ( 19 ). The seventh contact ( 17 ″) is called a phase-3-contact and is short-circuited by way of an electric line (L 3 ″) with the positive direct-current contact ( 18 ) and the direct-current line (DC+). The short-circuiting between the phase-2-contact and the negative direct-current contact and the short-circuiting between the phase-3-contact and the positive direct-current contact preferably takes place within the charging socket by a connection with a busbar or by a crimping of the corresponding lines, i.e. line (L 3 ′″) with the direct-current line (dc+) and line (L 2 ″) with the direct-current line (dc−). 
     The charging socket in  FIGS. 3 and 4  has a protective cap, which can take up a closed position ( 20   b  in  FIG. 3 ) or an open position ( 20   a  in  FIG. 4 ). The position of the cap can be determined by a cap sensor  21 , and information concerning the cap position can be transmitted to the charging control device  5   c . The recognition of the cap position can be based on the detection of a magnetic field of the cap or of a part of the cap by means of a Hall sensor. Furthermore, the position of the cap can be mechanically adjusted by the charging control device  5   c.    
     In  FIG. 3 , a charging plug  3   a  can be connected to the charging socket. The charging plug is connected with the charging source  2   a  by way of a cable. The charging plug has maximally seven poles. In this case, it should be taken into account that not necessarily every pole of the charging plug also has to be electrically assigned. A charging plug may, for example, be used which has a 7-pole construction and, in this case, has five assigned poles, i.e. five electrically active poles. The unassigned poles may be made of a conductive or non-conductive material or at best may be implemented as briefly indicated. 
     As in  FIGS. 1 and 2 , an exclusive plug-socket connection with the same assignments can also be established between the charging plug and the charging socket. This means in  FIG. 3  that, in the case of a charging connection, each electric pole of the plug is electrically connected with a predetermined contact of the first seven contacts of the charging socket. 
     In  FIG. 3 , a Type 2 plug of the International Draft Standard IEC 62196 for the wired charging of electric vehicles is used without limiting the generality. 
     When, in  FIG. 3 , a 1-phase alternating current is present as a result of the charging source, for example, in the case of a charging connection between the fourth contact  14  and the fifth contact  15 , the energy accumulator can be charged by way of the charging device  6  when the contactors  7  are open. 
     When the charging source provides direct current for DC low charging by way of the phase-2 contact and the phase-3 contact, the energy accumulator can be charged while the contactors are closed; provided that the protective cap is closed by the charging control device and the cap sensor transmits information concerning the closed position of the protective cap to the charging control device. It is only then that the contactors  7  can be closed by the charging control device for the charging. 
     The closed protective cap for the DC low charging ensures that the negative direct-current contact and the positive direct-current contact during DC low charging are not freely accessible so as to be touchable from the outside with respect to the body shell of the vehicle. This is necessary for the personal safety of the operator or user of the charging apparatus for the vehicle. 
     Since the direct-current lines (dc+ and dc−) are designed for DC high charging, DC low charging is possible according to the design. 
     In  FIG. 4 , a charging plug  3   b  can be connected to the charging socket while the protective cap is open. The charging plug is connected with the charging source  2   b  by way of a cable. The charging plug has maximally nine poles. In this case, it should be taken into account that not necessarily every pole of the charging plug also has to be electrically assigned. A charging plug may, for example, be used which has a 9-pole construction and, in this case, has five assigned poles, i.e. five electrically active poles. The unassigned poles may be made of a conductive or non-conductive material or at best may be implemented as briefly indicated. 
     As in  FIGS. 1, 2 and 3 , one exclusive plug-socket connection with the same assignments can also be established between the charging plug and the charging socket. This means in  FIG. 4  that, in the case of a charging connection, each electric pole of the plug is electrically connected with a predetermined contact of the nine contacts of the charging socket. 
     In  FIG. 4 , a Combo-2 plug of the International Draft Standard IEC 62196 for the wired charging of electric vehicles is used without limiting the generality. 
     When, in  FIG. 4 , a 1-phase alternating voltage is present as a result of the charging source, for example, in the case of a charging connection between the fourth contact  14  and the fifth contact  15 , the energy accumulator can be charged by way of the charging device when the contactors are open. 
     When the charging source provides directed current by way of the positive direct-current contact and the negative direct-current contact, for DC high charging, the energy accumulator can be charged while the contactors are closed. 
     The advantage of a charging apparatus having a charging socket according to  FIG. 3  or  FIG. 4  is achieved by the fact that, irrespective of whether the Type 2 plug or the Combo-Type 2 plug is available at a charging source, and irrespective of which charging type (alternating-current charging, DC low charging or DC high charging) is provided by the charging source, the energy accumulator of the vehicle is not only chargeable, but the type of charging provided by the charging station which allows the briefest charging period, can also be selected by the charging control device  5   c . This results in a high degree of flexibility for the user as well as a high availability of charging variants at a plurality of charging sources. The technical solution of  FIGS. 3 and 4  can be implemented in a cost-effective and installation-space-saving manner. The charging apparatus is easily operable for the user. In addition, it assures the user of a high degree of physical protection from touching high-voltage components. 
     Based on the statements in  FIG. 3  and  FIG. 4 , two additional possibilities are available, which consist of, in each case, connecting the phase 2 line (L 2 ″) and the phase 3 line (L 3 ″) in the form of a branching additionally with an alternating-current charging device, which is constructed as a 3 phase alternating-current charging device. The latter then has, in addition to the inputs for the neutral line (N) and the phase 1 line (L 1 ), an input for the branching of the phase 2 line and the phase 3 line. If the charging source supplies 3-phase alternating current while the charging connection is established by way of the neutral line (N), the phase 1 line (L 1 ), the branched phase 2 line and the branched phase 3 line, the energy accumulator can be charged with 3-phase alternating current when the contactors are open. If the charging connection for this 3-phase alternating-current charging is established with the Type 2 Combo plug, the protective cap is open. If the charging connection for this 3-phase alternating-current charging is established with the Type 2 plug, the protective cap is closed. 
     The implemented charging apparatuses are also suitable for transmitting electric energy into the vehicle in order to supply electric consuming devices of the vehicle with electric power when the vehicle is stationary and if the charging connection is established. An electric linking of these consuming devices can take place, for example, by way of the poles of the energy accumulator and possibly interposed DC converters. This is advantageous particularly in the case of a defective energy accumulator or in the case of an energy accumulator with a limited charge acceptance (for example, in the case of a full state of the charge). 
     The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.