Patent Publication Number: US-2010121507-A1

Title: Control device and control method for vehicle

Description:
TECHNICAL FIELD 
     The invention relates to a control device for a vehicle equipped with a power storage device and using at least a rotating electric machine as a drive source, and particularly to a technique that selectively activates an electric device related to charging when an external charging device charges a power storage device. 
     BACKGROUND ART 
     In recent years, attention has been given to hybrid vehicles and electric vehicles against the background of environmental issues. These vehicles are equipped with a power storage device supplying an electric power to an electric drive motor. However, the electric power of the power storage device is limited so that reduction of electric power consumption becomes an important issue in electric devices on the vehicle. 
     In view of the above issue, Japanese Patent Laying-Open No. 2002-125301 has disclosed an onboard device power saving device for an onboard device of a vehicle that reduces a quantity of electric power consumed by the onboard device as far as possible. This onboard device power saving device is a device for controlling the electric power supplied to the onboard device of the vehicle, and is characterized in that the onboard device power saving device includes electric power supply limiting means for limiting the electric power supplied to the onboard device according to an externally applied control signal. 
     Since the onboard device power saving device disclosed in the above publication limits the electric power supplied to the onboard device of the vehicle according to the externally applied control signal, it can significantly reduce the electric power wasted on the vehicle. Accordingly, the mileage of the vehicle can be increased. Further, when the onboard device power saving device receives a preset interrupt control signal while the electric power is not being supplied to the onboard device, the onboard device power saving device starts the electric power supply, and also provides a notification of the start of the electric power supply to an onboard device power saving control device arranged in an electric power control center via communication means. 
     However, the onboard device power saving device disclosed in the foregoing publication suffers from a problem that power consumption of an external charging device or a power storage device mounted on a vehicle cannot be reduced when the power storage device is charged with the external charging device. 
     When the external charging device performs the charging, the vehicle is at rest, and therefore onboard electric devices that are included in the plurality of electric devices and are not related to the charging are activated together with the electric devices related to the charging in some cases. This situation occurs because a group of the electric devices operating in charging are connected to the same power supply system as a group of the electric devices operating at the start of the vehicle although the former group of electric devices are not necessarily the same as the latter group of electric devices. Therefore, the electric power may be wasted. This may result in increase of a charge time. A power supply device that controls each of powers supplied to the respective electric devices, in which case it may be impossible to ensure a space for mounting the electric devices on the vehicle. 
     Further, when a plurality of electric devices connected to a communication line corresponding to the same power supply system are configured to operate such that only a part of the electric devices become active, a communication error may occur due to no response of the inactive electric device. For avoiding the occurrence of the communication error, it is necessary to set an error mask for each electric device so that changes in setting may be complicated. 
     DISCLOSURE OF THE INVENTION 
     An object of the invention is to provide a control device and a control method for a vehicle that can ensure a space for mounting, and further can selectively operate electric devices related to charging of a power storage device during the external charging for achieving reduction in power consumption during the external charging and reduction in charge time of the power storage device. 
     A control device for a vehicle according to an aspect has at least a rotating electric machine as a drive source. The vehicle includes a plurality of electric devices, a power storage device supplying an electric power to the rotating electric machine and the plurality of electric devices, and a connection unit connecting a charge cable of an external charging device charging the power storage device. The control device includes a first control unit transmitting an activation signal corresponding to an activating operation of the vehicle via a first communication line connected to a predetermined first electric device group in the plurality of electric devices and performing activation control on the first electric device group; and a second control unit transmitting an activation signal via a second communication line connected to a predetermined second electric device group, that is included in the plurality of electric devices and related to the charging by the external charging device and performing activation control on the second electric device group. 
     According to the invention, the second control unit transmits the activation signal via the second communication line and performs the activation control on each electric device in the second electric device group. Thereby, only the electric devices related to the charging can be activated while keeping the electric devices not related to the charging at rest. Therefore, wasting of the electric power can be suppressed. Consequently, it is possible to reduce the electric power consumed in the external charging device or the power storage device and to reduce a charge time required for charging the power storage device by the external charging device. Further, it is not necessary to arrange a power supply device controlling the power supply for each of the electric devices related to the charging so that a space for mounting the electric devices is not restricted. Accordingly, it is possible to provide the control device for the vehicle that ensures a mounting space, selectively operates the electric devices related to the charging of the power storage device when the external charging is performed, and thereby reduces the power consumption during the external charging and the charge time of the power storage device. 
     Preferably, the control device further includes a detecting unit detecting a position change of a member operated in charging by the external charging device. The second control member performs the activation control on the second electric device group when the position change of the member is detected. 
     According to this invention, when the position change of the member operated in charging by the external charging device is detected (e.g., when connection of the charge cable to the connection unit is detected), the activation signal is transmitted via the second communication line to perform the activation control on each electric device in the second electric device group. Thereby, only the electric devices related to the charging can be activated while keeping the electric devices not related to the charging at rest. Therefore, wasting of the electric power can be suppressed. Consequently, it is possible to reduce the electric power consumed in the external charging device or the power storage device and to reduce a charge time required for charging the power storage device by the external charging device. Further, it is not necessary to arrange a power supply device controlling the power supply for each of the electric devices related to the charging so that a space for mounting the electric devices is not restricted. 
     Further preferably, the detecting unit detects the connection of the charge cable to the connection unit. 
     According to this invention, when the connection of the charge cable to the connection unit is detected, the activation signal is transmitted via the second communication line to perform the activation control on each electric device in the second electric device group. Thereby, only the electric devices related to the charging can be activated while keeping the electric devices not related to the charging at rest. 
     Further preferably, the second electric device group includes an electric device connected to the first and second communication lines. The electric device is activated based on at least one of the activation signals transmitted via respective first and second communication lines. 
     According to this invention, the electric device is activated based on at least one of the activation signals transmitted via respective first and second communication lines. Thereby, the electric device can be activated in response to the connection of the charge cable to the connection unit or the activation operation of the vehicle. 
     Further preferably, the second electric device group includes first and second electric devices. The local communication line connects the first and second electric devices together. 
     According to this invention, the local communication line connects the first and second electric devices together. When the charge cable is connected to the connection unit to activate the second electric device group, both the first and second electric devices are activated so that it is possible to, suppress the occurrence of the communication error due to no response at the time of communication via the local communication line. Further, it is not necessary to set an error mask or the like for avoiding the communication error for each of the electric devices. 
     Further preferably, the power storage device includes a power storage device on a high voltage side and a power storage device on a low voltage side. The second electric device group includes an electric device operating in connection with the power storage device on the high voltage side. The control device further includes a load control unit controlling the electric device to reduce a load quantity of the electric load during operation of the electric device when the connection of the charge cable is detected. 
     According to this invention, when the connection of the charge cable is detected, the control device controls the electric device to reduce the load quantity of the electric load during the operation of the electric device. Thereby, it is possible to reduce the power consumption of the external charging device or the power storage device during the external charging. 
     Further preferably, the second electric device group includes a converter charging the power storage device on the low voltage side with the electric power of the power storage device on the high voltage side. The load control unit controls the converter to lower the output voltage during the charging of the power storage device on the low voltage side by the converter when the connection of the charge cable is detected. 
     According to the invention, when the connection of the charge cable to the connection unit is detected, the converter is controlled to lower its output voltage. Therefore, it is possible to reduce the power consumption of the resistive load that operates with the power supplied from the converter. 
     Further preferably, the load control unit controls the electric device to stop a function not related to the charging when the electric device operates. 
     According to this invention, the load control unit controls the electric device to stop the function not related to the charging when the connection of the charge cable is detected. Thereby, the power consumption of the external charging device or the power storage device can be reduced during the external charging. 
     Further preferably, the power storage device includes a power storage device on a high voltage side and a power storage device on a low voltage side. The electric devices of the second electric device group operate by receiving the electric power from the power storage device on the low voltage side during the activation control. The control device includes a relay changing collectively a state of power supply from the power storage device on the low voltage side to the second electric device group to one of a supply state and a non-supply state; a position change detecting unit detecting a position change of a member operated in charging by the external charging device; and an activating operation detecting unit detecting an activating operation of the vehicle. The control device controls the relay to change the state of power supply to the supply state when at least one of the position change of the member and the activation operation of the vehicle is detected. 
     According to this invention, the relay can collectively change the states of power supply to the second electric device group to the supply state or the non-supply state. Therefore, as compared with the case where an independent relay of the like is arranged for each electric device, it is possible to suppress the increase in mass. Further, it is possible to prevent deterioration, which may be caused by provision of the plurality of relays, in mountability of other parts on the vehicle. Accordingly, the space for mounting the electric devices can be ensured. 
     Further preferably, the electric device of the first electric device group operates by receiving the electric power from the power storage device on the low voltage side during the activation control. The control device further includes a relay changing collectively a state of power supply from the power storage device on the low voltage side to the first electric device group to one of a supply state and a non-supply state. The control device controls the relay to change the state of power supply to the supply state when the activation operation of the vehicle is detected. 
     According to this invention, when the activation operation of the vehicle is detected, the states of power supply to the first and second electric device groups collectively change to the supply state, and the electric devices on the vehicle operates so that the state in which the vehicle can run is attained. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram showing a structure of a hybrid vehicle according to a first embodiment of the invention. 
         FIG. 2  shows a power storage device mounted on the hybrid vehicle. 
         FIG. 3  is a diagram (first diagram) showing structures of a control device for a vehicle and electric devices connected to the control device according to the first embodiment. 
         FIG. 4  is a functional block diagram of the control device for the vehicle according to the first embodiment. 
         FIG. 5  is a flow chart (first flowchart) illustrating a control structure of a program executed by the control device for the vehicle according to the first embodiment. 
         FIG. 6  is a flowchart (second flowchart) illustrating the control structure of the program executed by the control device for the vehicle according to the first embodiment. 
         FIG. 7  is a diagram (second diagram) showing structures of the control device for the vehicle and the electric devices connected to the control device according to the first embodiment. 
         FIG. 8  is a diagram (third diagram) showing structures of the control device for the vehicle and the electric devices connected to the control device according to the first embodiment. 
         FIG. 9  is a diagram showing structures of a control device for a vehicle and electric devices connected to the control device according to the second embodiment. 
         FIG. 10  is a functional block diagram of the control device for the vehicle according to the second embodiment. 
         FIG. 11  is a flowchart (first flowchart) illustrating a control structure of a program executed by the control device for the vehicle according to the second embodiment. 
         FIG. 12  is a flowchart (second flowchart) showing the control structure of the program executed by the control device for the vehicle according to the second embodiment. 
     
    
    
     BEST MODES FOR CARRYING OUT THE INVENTION 
     Embodiments of the invention will now be described with reference to the drawings. In the following description, the same portions bear the same reference numbers and the same names, and achieve the same functions. Therefore, description thereof is not repeated. 
     &lt;First Embodiment&gt; 
       FIG. 1  is a block diagram showing a structure of a hybrid vehicle  10  according to an embodiment of the invention. 
     Referring to  FIG. 1 , hybrid vehicle  10  includes front wheels  20 R and  20 L, rear wheels  22 R and  22 L, an engine  450 , a planetary gear PG, a differential gear DG, and gears  40  and  60 . 
     Hybrid vehicle  10  further includes a battery  130 , a booster converter  200  boosting a DC power supplied from battery  130  and an inverter  140  transferring the DC power to or from booster converter  200 . 
     Hybrid vehicle  10  further includes a motor generator MG 1  that receives a drive power of engine  450  via planetary gear PG to generate an electric power, and a motor generator MG 2  having a rotation axis connected to planetary gear PG. Inverter  140  is connected to motor generators MG 1  and MG 2  to perform conversion between an AC power and the DC power provided from a booster circuit. 
     Planetary gear PG includes a sun gear, a ring gear, pinion gears meshing with both the sun and ring gears, and a planetary carrier rotatably carrying the pinion gears around the sun gear. Planetary gear PG has first, second and third rotation axes. The first rotation axis is the rotation axis of the planetary carrier connected to engine  450 . The second rotation axis is the rotation axis of the sun gear connected to motor generator MG 1 . The third rotation axis is the rotation axis of the ring gear connected to motor generator MG 2 . 
     The third rotation axis is provided with a gear  40 . Gear  40  drives a gear  60  to transmit a mechanical power to differential gear DG, which transmits the mechanical power received from gear  60  to front wheels  20 R and  20 L, and also transmits the rotation power of front wheels  20 R and  20 L to the third rotation axis of planetary gear PG via gears  60  and  40 . 
     Planetary gear PG operates to split the power for engine  450  and motor generators MG 1  and MG 2 . More specifically, planetary gear PG determines the rotation of one of the three rotation axes according to the rotations of the other two rotation axes. Therefore, engine  450  is kept to operate in an range of the highest efficiency and, at the same time, motor generator MG 2  is driven by controlling a quantity of the electric power generated by motor generator MG 1  so that a vehicle speed is controlled, and the vehicle of high energy efficiency is implemented as a whole. 
     Battery  130  that is a DC power supply is formed of, e.g., a secondary battery such as a nickel hydrogen battery or a lithium ion battery. Battery  130  supplies the DC power to booster converter  200 , and is charged with the DC power supplied from booster converter  200 . 
     Booster converter  200  boosts the DC voltage supplied from battery  130 , and supplies the boosted DC voltage to inverter  140 . Inverter  140  converts the supplied DC voltage to the AC voltage for performing the drive control of motor generator MG 1  at the time of engine starting. After the start of the engine, the AC power generated by motor generator MG 1  is converted to the DC power, and then is converted by booster converter  200  to attain a voltage that is appropriate for the charging of battery  130 . Battery  130  is charged with the power thus converted. 
     Inverter  140  drives motor generator MG 2 . Motor generator MG 2  assists engine  450  to drive front wheels  20 R and  20 L. In the braking operation, motor generator MG 2  performs a regenerative operation to convert rotation energy of the wheels to electric energy. The electric energy thus obtained returns to battery  130  via inverter  140  and booster converter  200 . 
     Battery  130  is a battery assembly including a plurality of battery units B 0 -Bn connected in series together. System main relays SR 1  and SR 2  are arranged between booster converter  200  and battery  130  for interrupting a high voltage when the vehicle is not operating. 
     Hybrid vehicle  10  further includes an ignition (which may also be referred to as “IG” hereinafter) switch  88  that is an input unit receiving a vehicle start request instruction from a driver, an air conditioner  90 , a door lock  92 , a navigation system  94 , an electrically-operated stabilizer  96 , headlamps  98 , engine  450 , inverter  140 , booster converter  200  and a control device  300  controlling these electric devices and units. IG switch  88  may be formed of a push button or a rotary switch, and is not particularly restricted. 
     Hybrid vehicle  10  further includes a socket  160  that is a connection unit for connecting a plug  1040  arranged at an end of a charge cable  1020  extending from an external charging device  1000 , a coupling determination sensor  180  arranged in socket  160  for sensing a coupling determination element  1060  of plug  1040  and thereby recognizing the connection of plug  1040  to socket  1040 , and a charge inverter  120  (i.e., an inverter for charging) that receives the AC power from external charging device  1000  via socket  160 . Charge inverter  120  is connected to battery  130 , and supplies the DC power for charging to battery  130 . Coupling determination sensor  180  may be of any type and may be configured, e.g., to detect a magnet on the plug side, to be of a push button type (i.e., to be pushed in when the plug is plugged) or to detect a connection resistance of a power supply path. When plug  1040  is connected to socket  160 , coupling determination sensor  180  transmits a plug connection signal to control device  300 . 
     In this embodiment, external charging device  1000  supplies the electric power to battery  130  via charge inverter  120 . However, the manner of the external charging is not restricted to this. For example, battery  130  may be charged by supplying the electric power of external charging device  1000  through a neutral point of motor generator MG 1  or MG 2 . 
     In this embodiment, as shown in  FIG. 2 , the vehicle is equipped with battery  130  that is the power storage device on a high voltage side as well as a battery  132  that is a power storage device on a low voltage side for supplying an electric power to accessories. Battery  130  is connected to a DC-DC converter  250  via a high-voltage power line  134 . Battery  132  is connected to DC-DC converter  250  via a low-voltage power line  136 . A load  150  is connected in parallel to DC-DC converter  250  and battery  132 . 
     DC-DC converter  250  receives an input power from battery  130 , and outputs a voltage that is set. Battery  132  is charged with the power supplied from DC-DC converter  250 , and supplies the power to load  150 . 
     In this embodiment, load  150  is formed of, e.g., air conditioner  90 , door lock  92 , navigation system  94 , electrically-operated stabilizer  96 , headlamps  98  and the like, but is not restricted to these electric devices. 
     Low-voltage power line  136  includes a power supply system of the accessory (which will be referred to as the “ACC” hereinafter) as well as respective power supply systems of IG 1 , IG 2  and PLG. 
     When the driver operates IG switch  88  to turn on a relay of the ACC, an activation signal is transmitted to the electric devices connected to the power supply system of the ACC, and the power of battery  132  is supplied to the electric devices of the power supply system to activate them. The electric devices of the power supply system of the ACC include, e.g., a radio, an audio device and/or the like, but are not restricted to them. 
     When the driver operates IG switch  88  to turn on the relays of IG 1  and IG 2 , the activation signals are transmitted to electric devices connected to the power supply systems of IG 1  and IG 2 , respectively. The electric devices of the power supply systems of IG 1  and IG 2  include, e.g., the electric devices already specified as an example of load  150 , but are not restricted to them. 
     As shown in  FIG. 3 , control device  300  of the vehicle according to the embodiment includes a power supply ECU (Electronic Control Unit)  320  and an HV-ECU  330 . A communication line  325  is connected to power supply ECU  320  and HV-ECU  330 . Power supply ECU  320  receives an IG switch signal supplied from IG switch  88 , a plug connection signal supplied from coupling determination sensor  180  and a charge determination signal supplied from HV-ECU  330  via communication line  325 . 
     Power supply ECU  320  is connected to relays  302 ,  304  and  306  corresponding to communication lines  322 ,  324  and  326  of the power supply systems of the ACC, IG 1  and IG 2 , respectively. 
     For example, when the driver operates IG switch  88  to perform an operation corresponding to the activation request for the electric devices connected to the power supply system of the ACC, power supply ECU  320  turns on relay  302  in response to an IG switch signal provided from IG switch  88 . When relay  302  is turned on, the power is supplied from battery  132  to the electric devices connected to the power supply system of the ACC according to the activation signal transmitted via communication line  322  so that each electric device is activated. 
     When the driver operates IG switch  88  to perform an operation corresponding to the activation request for the electric devices connected to the power supply systems of IG 1  and IG 2 , power supply ECU  320  turns on relays  304  and  306  in response to the IG switch signal provided from IG switch  88 . When relays  304  and  306  are turned on, the electric power of battery  132  is supplied to the electric devices connected to the power supply systems of IG 1  and IG 2  according to the activation signals transmitted via communication lines  324  and  326  so that these electric devices are activated. In this embodiment, the power supply systems of load  150  include the two power supply systems of IG 1  and IG 2 . However, this is not restrictive, and the power supply system of load  150  may be formed on one power supply system including IG 1  and IG 2 . 
     Further, power supply ECU  320  is connected to relay  308  corresponding to a communication line  328  of the power supply system of the PLG. The invention has the following distinctive feature. When power supply ECU  320  detects the connection of charge cable  1020  to socket  160  of plug  1040 , power supply ECU  320  transmits an activation signal via communication line  328  to the predetermined electric device group related to the charging by external charging device  1000 , and thereby controls the activation of the electric device group. 
     More specifically, when power supply ECU  320  receives the plug connection signal from coupling determination sensor  180 , it turns on relay  308 . When relay  308  is turned on, the power of battery  132  is supplied to the electric devices connected to the power supply system of the PLG to turn on them according to the activation signal transmitted via communication line  328 . 
     In this embodiment, the electric devices connected to the power supply system of the PLG are HV-ECU  330  and navigation system  94 . However, the device may be a device other than navigation system  94  provided that the electric device operates in connection with the charging. For example, it may be an indicator such as LEDs (Light Emitting Diodes) arranged on an install panel for indicating that the charge is being performed. 
     Navigation system  94  is connected to communication lines  322  and  328  via diodes to form an OR circuit  310 , respectively. OR circuit  310  activates navigation system  94  in response to the turn-on of relay  308  or  302 . 
     HV-ECU  330  is connected via a relay  350  to a power supply line  360  of the power supply system of the electric devices that relate to the operations of MG 1  and MG 2  and will be referred to as the “hybrid devices” hereinafter. HV-ECU  330  is connected to power supply line  360  via a power supply line  362 . The hybrid devices include, e.g., inverter  140 , booster converter  200 , a battery ECU  340  and charge inverter  120 , but are not restricted to these electric devices. 
     Inverter  140  is provided with a cooling pump  142  for circulation in a cooling system cooling inverter  140 , and cooling pump  142  operates according to the operation of inverter  140 . Battery ECU  340  controls an operation quantity of a cooling fan  342  that supplies a cooling air to battery  130 . 
     HV-ECU  330  is activated by the activation signal from power supply ECU  320  when relay  306  or  308  is turned on. When HV-ECU  330  is activated, relay  350  is turned on. When relay  350  is turned on, the hybrid devices are activated according to activation signals transmitted to the respective hybrid devices. In this operation, the power is supplied to the hybrid devices via power supply line  360 , and the power is also supplied to HV-ECU  330  via power supply line  362 . 
     A charge-time-dedicated communication line  336  (i.e., a communication line dedicated to communications during the charging operation) connects HV-ECU  330  to navigation system  94 . Further, charge-time-dedicated communication line  336  and a communication line  338  branching from charge-time-dedicated communication line  336  connect HV-ECU  330  to each hybrid device. 
     For example, during the charging by external charging device  1000 , battery ECU  340  or HV-ECU  330  transmits the charge information indicating a state of charge (e.g., SOC (State Of Charge) of battery  130  to navigation system  94  via charge-time-dedicated communication lines  336  and  338 : Navigation system  94  displays the state of charge of battery  130  based on the received charge information. Alternatively, navigation system  94  may be configured to display, on its display unit, the state of charge of battery  130  based on a display control signal transmitted via charge-time-dedicated communication lines  336  and  338  from battery ECU  340  or HV-ECU  330 . 
     HV-ECU  330  may be configured to control the hybrid devices to decrease the load quantity of the electric load during the operation of the hybrid devices or to stop the functions unrelated to the charging during the operation of the hybrid devices, when the connection of plug  1040  of charge cable  1020  is detected. In the following description, the above manner of the control will be referred to as the “load control”. 
     For example, HV-ECU  330  may be configured to reduce as far as possible the operation quantity of cooling pump  142  of the cooling system arranged in inverter  140  or to stop the operation of cooling pump  142  according to the operation state (e.g., temperature of cooling water or the like) thereof. Alternatively, HV-ECU  330  may be configured to reduce as far as possible the operation quantity of cooling fan  342  of battery  130  of which operation quantity is controlled by battery ECU  340 , or to stop the operation of cooling fan  342  according to the state of battery  130  (e.g., temperature of battery  130  or the like). 
     Further, HV-ECU  330  may control the output voltage of DC-DC converter  250  to become lower than the output voltage in the ordinary operation. HV-ECU  330  is merely required to control DC-DC converter  250  such that the output voltage may become lower than the voltage attained in the ordinary operation. For example, when the output voltage of DC-DC converter  250  is  13 . 5  V in the ordinary operation and HV-ECU  330  detects the connection of plug  1040  of charge cable  1020 , DC-DC converter  250  may be controlled to output a predetermined voltage lower than 13.5 V. 
     In this embodiment, cooling pump  142 , cooling fan  342  and DC-DC converter  250  have been described as an example of the form of the load control. However, the electric load is not restricted to them provided that the load control is performed on the electric load that is not related to the charging by external charging device  1000 . For example, it is merely required to reduce the operation quantity of the electric load that is not related to the charging or to stop the operation thereof, depending on the manner or type of the charging. 
       FIG. 4  is a functional block diagram of control device  300  of the vehicle according to the embodiment. Power supply ECU  320  includes an input interface (which will be referred to as an “input I/F” hereinafter)  500 , a processing unit  510 , a storage unit  530  and an output interface (which will be referred to as an “output I/F” hereinafter)  540 . 
     Input I/F  500  receives an IG switch signal provided from IG switch  88 , a plug connection signal provided from coupling determination sensor  180  and a charge determination signal provided from HV-ECU  330 , and transmits them to processing unit  510 . Processing unit  510  includes a connection determining unit  512  and a relay control unit ( 1 )  514 . 
     Connection determining unit  512  determines whether charge cable  1020  is connected or not, according to the plug connection signal. Connection determining unit  512  may be configured to turn on a connection determination flag when it determines that charge cable  1020  is connected, and to turn off the connection determination flag when it determines that charge cable  1020  is not connected (i.e., is disconnected). 
     When the connection of charge cable  1020  is determined, relay control unit ( 1 )  514  produces a control signal for turning on relay  308 , and transmits the produced control signal to relay  308  via output I/F  540 . 
     Further, when relay control unit ( 1 )  514  receives the charge determination signal indicating the completion of the charging of battery  130 , it produces the control signal for turning off relay  308 , and transmits the produced control signal to relay  308  via output I/F  540 . 
     Relay control unit ( 1 )  514  may be configured to produce the control signal that turns on relay  308  when the communication determination flag is turned on. When relay  308  is turned on, the activation signal is transmitted via a communication line  334  to HV-ECU  330 . When relay  308  is turned off in response to completion of the charging of battery  130 , HV-ECU  330  stops after it stops the hybrid devices. 
     In this embodiment described above, each of connection determining unit  512  and relay control unit ( 1 )  514  is implemented by software and particularly by executing a program stored in storage unit  530  by processing unit  510 , i.e., a CPU (Central Processing Unit). However, these may be implemented by hardware. The above program is stored on a recording medium for carrying them on the vehicle. 
     Storage unit  530  stores various kinds of information, programs, thresholds, maps and the like. When necessary, processing unit  510  reads or stores such data from/in storage unit  530 . 
     HV-ECU  330  includes an input I/F  550 , a processing unit  560 , a storage unit  570  and an output I/F  580 . Input I/F  500  receives an SOC signal provided from battery ECU  340  and the activation signal provided from power supply ECU  320 , and transmits them to processing unit  510 . Processing unit  560  includes a relay control unit ( 2 )  562 , a load control unit  564 , a voltage setting unit  566 , a converter control unit  568  and a charge completion determining unit  572 . 
     When relay control unit ( 2 )  562  receives the activation signal from power supply ECU  320  via input I/F  550 , it produces a control signal turning on relay  350 , and transmits the produced control signal to relay  350  via output I/F  580 . Further, when relay control unit ( 2 )  562  enters a state in which it does not receive the activation signal from power supply ECU  320 , it stops the operations of the hybrid devices, produces the control signal turning off relay  350  and transmits the produced control signal to relay  350  via output I/F  580 . 
     Load control unit  564  executes load control. For example, load control unit  564  produces the load control signal to reduce the operation quantity of cooling pump  142  that operates according to the operation of inverter  140 , or to stop the operation of cooling pump  142 . Load control unit  564  transmits the produced load control signal to cooling pump  142  via output I/F  580  and charge-time-dedicated communication line  338 . Further, load control unit  564  may be configured to produce the load control signal to reduce the operation quantity of cooling fan  342  (i.e., the operation quantity controlled by battery ECU  340 ), or to stop the operation of cooling fan  342 . 
     Voltage setting unit  566  sets the output voltage of DC-DC converter  250 . For example, when voltage setting unit  566  receives the activation signal from communication line  334  via input I/F  550 , it sets the output voltage of DC-DC converter  250  to a predetermined voltage lower than the ordinary output voltage. 
     Converter control unit  568  produces the control signal corresponding to the set voltage, and transmits the produced control signal to DC-DC converter  250  via output I/F  580 . 
     Charge completion determining unit  572  determines whether external charging device  1000  has completed the charging of battery  130  or not, based on the SOC signal provided from battery ECU  340 . For example, charge completion determining unit  572  determines whether the quantity of charge of battery  130  is equal to or larger than a predetermined quantity of charge, or not. Further, charge completion determining unit  572  produces the charge determination signal indicating a result of the determination, and transmits the produced charge determination signal to power supply ECU  320  via output I/F  580  and communication line  325 . 
     In this embodiment described above, each of relay control unit ( 2 )  562 , load control unit  564 , voltage setting unit  566 , converter control unit  568  and charge completion determining unit  572  is implemented by software and particularly by executing a program stored in storage unit  570  by processing unit  560 , i.e., the CPU. However, these may be implemented by hardware. The above program is stored on a recording medium for carrying them on the vehicle. 
     Storage unit  570  stores various kinds of information, programs, thresholds, maps and the like. When necessary, processing unit  560  reads or stores such data from/in storage unit  570 . 
     Referring to  FIG. 5 , description will be given on the control structure of the program executed by control device  300  of the vehicle according to the embodiment. When the program is executed, control device  300  implements the activation control sequence of the electric devices in the state where charge cable  1020  is connected. 
     In a step (which will be referred to as “S” hereinafter)  100 , power supply ECU  320  determines whether plug  1040  of charge cable  1020  is connected to socket  160  or not. More specifically, when power supply ECU  320  receives the plug connection signal from coupling determination sensor  180 , it determines that plug  1040  is connected to socket  160 . When it is determined plug  1040  is connected to socket  160  (YES in S 100 ), the process proceeds to S  102 . Otherwise (NO in S 100 ), the process proceeds to S 110 . 
     In S 102 , power supply ECU  320  turns on relay  308 . When relay  308  is turned on, the activation signal is transmitted via communication line  334  to HV-ECU  330 . 
     In S 104 , HV-ECU  330  implements the load control. In S 106 , HV-ECU  330  changes the set voltage of DC-DC converter  250  to a predetermined voltage lower than the ordinary output voltage. In S 108 , HV-ECU  330  controls the output voltage of DC-DC converter  250  to attain the set voltage. 
     In S 110 , power supply ECU  320  will be on standby until a predetermined time elapses. More specifically, power supply ECU  320  measures the elapsed time by a timer or the like. Thus, power supply ECU  320  resets a count to an initial value, and then starts to increment the count by a predetermined value. Power supply ECU  320  returns the processing to S 100  when the count attains a value corresponding to a predetermined elapsed time. The predetermined elapsed time is not particularly restricted. 
     Based on the structure and flowchart described above, control device  300  of the vehicle according to the embodiment performs the operation corresponding to the start control sequence as described below. 
     When the vehicle is at rest and IG switch  88  is off, coupling determination sensor  180  transmits the plug connection signal to power supply ECU  320  of control device  300  when plug  1040  of charge cable  1020  is connected to socket  160 . When power supply ECU  320  receives the plug connection signal, it determines that plug  1040  is connected to socket  160  (YES in S 100 ). 
     At this time, power supply ECU  320  turns on relay  308 . In response to the turn-on of relay  308 , the activation signal is transmitted to HV-ECU  330  via communication line  334 . Further, the activation signal is transmitted to navigation system  94  via communication line  328 . Navigation system  94  is activated by receiving the power from battery  132  in response to the reception of the activation signal. At this time, navigation system  94  displays the state of charge of battery  132  charged by external charging device  1000 . 
     HV-ECU  330  is activated in response to reception of the activation signal, and turns on relay  350  to execute the load control corresponding to the external charging (S 104 ). Further, HV-ECU  330  changes the set voltage of DC-DC converter  250  to a voltage lower than the ordinary output voltage (S 106 ), and controls DC-DC converter  250  to output the voltage equal to the voltage thus set (S 108 ). When the plug connection signal is not received (NO in S 100 ), HV-ECU  330  will be on standby until a predetermined time elapses (S 110 ). 
     Referring to  FIG. 6 , description will be given on the control structure of the program executed by control device  300  of the vehicle according to the embodiment. By executing the program, control device  300  implements an end control sequence of the electric devices at the time of disconnection of charge cable  1020 . 
     In S 200 , power supply ECU  320  determines whether plug  1040  of charge cable  1020  is disconnected from socket  160  or not. More specifically, when power supply ECU  320  enters the state in which it does not receive the plug connection signal from coupling determination sensor  180 , power supply ECU  320  determines that plug  1040  is disconnected. When power supply ECU  320  keeps the state in which it receives the plug signal, power supply ECU  320  determines that plug  1040  is disconnected. When power supply ECU  320  determines that plug  1040  is disconnected from socket  160  (YES in S 200 ), the process proceeds to S 204 . Otherwise (NO in S 200 ), the process proceeds to S 202 . 
     In S 202 , power supply ECU  320  determines whether it receives the charge determination signal indicating the completion of charging of battery  130  from HV-ECU  330  or not. When power supply ECU  320  receives the charge determination signal indicating the completion of charging (YES in S 202 ), the process proceeds to step S 204 . Otherwise (NO in S 202 ), the process returns to S 200 . 
     In S 204 , power supply ECU  320  turns off relay  308 . This stops the electric devices that were activated when plug  1040  was connected to socket  160  and relay  308  was turned on. More specifically, when power supply ECU  320  turns on relay  308 , HV-ECU  330  stops the operations of the hybrid devices, and then turns off relay  350  to stop the operation of HV-ECU  330  itself. 
     Based on the structure and flowchart described above, control device  300  of the vehicle according to the embodiment performs the operation corresponding to the end control sequence as described below. 
     It is assumed that plug  1040  of charge cable  1020  is connected to socket  160 . 
     When the state in which plug  1040  is connected to socket  160  is kept (NO in S 200 ) and HV-ECU  330  issues the charge determination signal indicating the completion of charging of battery  130  (YES in S 202 ), relay  308  is turned off (S 204 ). When plug  1040  is disconnected from socket  160  (YES in S 200 ), relay  308  is turned off (S 204 ). 
     When relay  308  is turned off, HV-ECU  330  stops relay  350  to stop the operation of HV-ECU  330  itself after it stops the operations of the hybrid devices. 
     In the control device for the vehicle according to the embodiment, as described above, when the connection of the plug of the charge cable is detected, the power supply ECU transmits the activation signal via the communication line to perform the activation control on the electric device group related to the charging by the external charging device. Thereby, the control device can start only the electric devices related to the charging while keeping the electric devices not related to the charging at rest. Therefore, wasting of the electric power can be suppressed. Consequently, it is possible to reduce the power consumption in the external charging device or the battery, and further to reduce the charge time required for charging the power storage device by the external charging device. Since it is not necessary to employ the power supply device controlling the supplied power for each of the electric devices related to the charging, the space for mounting the electric devices is not restricted. Accordingly, it is possible to provide the control device and the control method for the vehicle that ensure the mounting space, selectively operate the electric devices related to the charging of the power storage device when the external charging is performed, and thereby reduce the power consumption during the external charging and the charge time of the power storage device. 
     Further, the activation signal is provided to the electric devices (the navigation system in this embodiment) via the OR circuit from the communication line corresponding to the power supply system of the ACC and the communication line corresponding to the power supply system dedicated to the charge operation. Thereby, in addition to the ordinary time when the vehicle is activated, the electric devices can be activated when the external charging device charges the power storage device. 
     Further, the electric devices related to the charging by the external charging device are connected together by the charge-time-dedicated communication line. During the external charging, the electric devices related to the charging are active so that it is possible to suppress the occurrence of the communication error due to no response in the communication operation. Accordingly, it is not necessary to set an error mask or the like for avoiding the communication error for each of the electric devices. 
     When the connection of the plug of the charge cable is detected, the load control is performed on the electric devices to reduce the load quantity of the electric load during the operation of the electric devices. Thereby, the power consumption of the external charging device or the battery can be reduced during the external charging. 
     When the connection of the plug of the charge cable is detected, the control is performed to lower the output voltage of the DC-DC converter so that the power consumption of the resistive load or the like such as a heater can be reduced. 
     Further, when the plug is disconnected from the socket or the charging of the battery on the high voltage side is completed, the electric devices related to the charging in the external charging operation are stopped so that the power consumption of the battery can be small. 
     The control device for the vehicle according to the embodiment is not particularly restricted to the structure shown in  FIG. 3 . For example, as shown in  FIG. 7 , control device  300  may not employ communication lines  336  and  338  in  FIG. 3 , and alternatively may employ a local communication line  352  connecting HV-ECU  330  to the navigation system as well as a communication line  354  that is arranged independently of local communication line  352  for connecting HV-ECU  330  to the hybrid devices. This structure can achieve substantially the same effect as the structure of control device  300  shown in  FIG. 3  by the substantially same operations. 
     Alternatively, control device  300  may include, e.g., an ECU  400  having the functions of power supply ECU  320  and HV-ECU  330  in an integrated function as shown in  FIG. 8  instead of power supply ECU  320  and HV-ECU  330  in  FIG. 3 . Further, instead of communication lines  336  and  338  in  FIG. 3 , it may include local communication line  352  connecting an integrated ECU  400  to the navigation system as well as communication line  354  arranged independent of local communication line  352  for connecting integrated ECU  400  to the hybrid devices. This structure can achieve substantially the same effect as the structure of control device  300  shown in  FIG. 3  by the substantially same operations. 
     In this embodiment described above, when the plug of the charge cable is connected to the socket, the plurality of electric devices mounted on the vehicle are controlled to activate the group of the electric devices related to the external charging. However, the control device may be configured to activate the electric devices related to the charging in response to the detection of a change in position of a member that is operated in charging by the external charging device. For example, when a cover member is arranged for the socket, an electric device group related to the external charging in the plurality of electric devices mounted on the vehicle may be activated when the cover member opens. 
     &lt;Second Embodiment&gt; 
     The control device for the vehicle according to the second embodiment will be described below. The control device for the vehicle according to the embodiment differs from that according to the first embodiment already described in the structure of control device  300 . Other structures are the same as those of the vehicle equipped with the control device according to the embodiment already described. The same portions bear the same reference numbers and achieve the same functions. Therefore, description thereof is not repeated. 
     As shown in  FIG. 9 , control device  300  of this embodiment includes a PM-(Power Management-) ECU  600 , an IG power supply relay  602  and an HV+PLG power supply relay  604 . The vehicle is equipped with a plurality of electric devices, which include an electric device group  700  that is activated in response to reception of the activation signal transmitted according to an activation operation, e.g., on IG switch  88  of the vehicle, and an electric device group  800  related to the charging by external charging device  1000 . The plurality of electric devices may be configured to include at least one electric device that belongs to both electric device groups  700  and  800 . 
     PM-ECU  600  receives the IG switch signal from IG switch  88 , and also receives the plug connection signal from coupling determination sensor  180 . 
     PM-ECU  600  is connected to IG power supply relay  602  corresponding to the power supply system of the IG and a HV+PLG power supply relay  604  corresponding to the power supply systems of the hybrid devices and the PLG. PM-ECU  600  may be configured to connect further to a relay (not shown) corresponding to the power supply system of the ACC. 
     For example, when the driver performs, on IG switch  88 , an operation corresponding to the activation request for the electric device connected to the power supply system of the IG, PM-ECU  600  receives the IG switch signal from IG switch  88 , and thereby PM-ECU  600  transmits the control signal to turn on IG power supply relay  602  and HV+PLG power supply relay  604 . 
     In response to the reception of the on signal from PM-ECU  600 , the state of power supply from battery  132  to the electric devices of the IG power supply system is changed by IG power supply relay  602  from a non-supply state to a supply state. Therefore, when IG power supply relay  602  is turned on, the power is supplied from battery  132  to electric devices  704  and  706  connected to electric device group  700  connected to the power supply system of the IG so that electric devices  704  and  706  are activated. 
     Further, HV+PLG power supply relay  604  changes collectively the states of power supply from battery  132  on the lower voltage side to respective electric devices  804 ,  806  and  808  of electric device group  800  to the supply state or the non-supply state. Electric devices  804 ,  806  and  808  include the hybrid devices (i.e., the electric devices related to the operation of MG 1  and MG 2 ) as well as the electric devices (e.g., navigation system  94 ) connected to the power supply system of the PLG. Therefore, when HV+PLG power supply relay  604  is turned on, battery  132  supplies the power to the hybrid devices and the electric devices connected to the PLG power supply system to activate them. 
     When the position change of the member that is operated for the charging by external charging device  1000  is detected, PM-ECU  600  controls HV+PLG power supply relay  604  to change the non-supply state to the supply state. 
     In this embodiment, when PM-ECU  600  receives the plug connection signal from coupling determination sensor  180 , it transmits the control signal to turn on HV+PLG power supply relay  604 . 
     PM-ECU  600  is connected to electric devices  704  and  706  of electric device group  700  via a communication bus  702 . Further, PM-ECU  600  is connected to electric devices  804 ,  806  and  808  of electric device group  800  via a communication bus  802 . 
     PM-ECU  600  has a gateway  606  connected to both communication buses  702  and  802 , and inhibits the data transfer between communication buses  702  and  802  when it receives the plug connection signal. 
     When PM-ECU  600  receives the plug connection signal from coupling determination sensor  180 , it performs the load control on the hybrid devices. The control manner of the load control is substantially the same as that already described in the first embodiment, and therefore description thereof is not repeated. 
       FIG. 10  is a functional block diagram of control device  300  of the vehicle according to this embodiment. PM-ECU  600  includes an input I/F  610 , a processing unit  620 , a storage unit  640  and an output I/F  650 . 
     Input I/F  610  receives the IG switch signal provided from IG switch  88  and the plug control signal provided from coupling determination sensor  180 , and transmits them to processing unit  620 . 
     Processing unit  620  includes a connection determining unit  622 , a relay control unit ( 1 )  624 , a gateway inhibit processing unit  626 , a load control unit  628 , a charge completion determining unit  630  and a relay control unit ( 2 )  632 . 
     Connection determining unit  622  determines whether charge cable  1020  is connected or not, based on the plug connection signal. For example, connection determining unit  622  may be configured to turn on a connection determination flag when it detects the connection of charge cable  1020 , and to turn off the connection determination flag when it detects the disconnection of charge cable  1020 . 
     When the connection of charge cable  1020  is detected, relay control unit ( 1 )  624  produces the control signal turning on HV+PLG power supply relay  604 , and transmits the produced control signal to HV+PLG power supply relay  604  via output I/F  650 . 
     Relay control unit ( 1 )  624  may be configured to produce the control signal turning on HV+PLG power supply relay  604  when the connection determination flag is turned on. 
     When the connection of charge cable  1020  is detected, gateway inhibit processing unit  626  inhibits the data transfer between communication buses  702  and  802  in gateway  606 . Gateway inhibit processing unit  626  may be configured to inhibit the data transfer between communication buses  702  and  802  when the connection determination flag is on. 
     Load control unit  628  implements the load control when the connection of charge cable  102  is detected. 
     Charge completion determining unit  630  determines whether the charging of battery  130  by external charging device  1000  is completed or not. For example, charge completion determining unit  630  determines whether the quantity of charge of battery  130  is equal to or larger than a predetermined quantity of charge or not. For example, charge completion determining unit  630  may be configured to determine whether the quantity of charge of battery  130  is equal to or larger than the predetermined quantity of charge or not, based on information that is received from the battery ECU (not shown) and relates to the quantity of charge of battery  130 . Alternatively, the SOC of battery  130  may be estimated using an open-circuit voltage of battery  130 , an integrated value of the charge/discharge current or the like, and charge completion determining unit  630  may determine whether the quantity of charge of battery  130  is equal to or larger than the predetermined quantity of charge, or not. 
     For example, charge completion determining unit  630  may be configured to turn on the completion determination flag when it determines that the charging of battery  130  is completed. 
     When charge completion determining unit  630  determines that the charging of battery  130  is completed, relay control unit ( 2 )  632  produces the control signal that turns off HV+PLG power supply relay  604 , and transmits the produced control signal to HV+PLG power supply relay  604  via output I/F  650 . 
     Relay control unit ( 2 )  632  may be configured to produce the control signal turning off HV+PLG power supply relay  604 , e.g., when the completion determination flag is turned on. 
     In this embodiment described above, each of connection determining unit  622 , relay control unit ( 1 )  624 , gateway inhibit processing unit  626 , load control unit  628 , charge completion determining unit  630  and relay control unit ( 2 )  632  is implemented by software and particularly by executing a program stored in storage unit  640  by processing unit  620  that is the CPU. However, these may be implemented by hardware. The above program is stored on a recording medium for carrying them on the vehicle. 
     Storage unit  640  stores various kinds of information, programs, thresholds, maps and the like. When necessary, processing unit  620  reads or stores such data from/in storage unit  640 . 
     Referring to  FIG. 11 , description will be given on the control structure of the programs executed by PM-ECU  600  that is the control device for the vehicle according to the embodiment. 
     In S 300 , PM-ECU  600  determines whether plug  1040  of charge cable  1020  is connected to socket  160  or not. More specifically, when PM-ECU  600  receives the plug connection signal from coupling determination sensor  180 , it determines that plug  1040  is connected to socket  160 . When PM-ECU  600  determines that plug  1040  is connected to socket  160  (YES in S 300 ), the process proceeds to  5302 . Otherwise (NO in S 300 ), the process proceeds to S 308 . 
     In  5302 , PM-ECU  600  turns on HV+PLG power supply relay  604 . In S 304 , PM-ECU  600  executes the gateway inhibit processing. Thus, PM-ECU  600  inhibits the data transfer between communication buses  702  and  802 . 
     In S 306 , PM-ECU  600  implements the load control. In  5308 , PM-ECU  600  keeps the standby state until a predetermined time elapses. More specifically, PM-ECU  600  measures the elapsed time by a timer or the like. Thus, PM-ECU  600  resets the count to an initial value, and then starts to increment the count by a predetermined value. PM-ECU  600  returns the processing to S 300  when the count attains a value corresponding to a predetermined elapsed time. The predetermined elapsed time is not particularly restricted. 
     Based on the structure and flowchart described above, control device  300  of the vehicle according to the embodiment performs the operation corresponding to the start control sequence as described below. 
     In the state where the vehicle is at rest and IG switch  88  is off, coupling determination sensor  180  transmits the plug connection signal to PM-ECU  600  when plug  1040  of charge cable  1020  is connected to socket  160 . When PM-ECU  600  receives the plug connection signal, it determines that plug  1040  is connected to socket  160  (YES in S 300 ). 
     At this time, PM-ECU  600  turns on HV+PLG power supply relay  604  (S 302 ). In response to the turn-on of HV+PLG power supply relay  604 , the activation signal is transmitted to the electric devices of electric device group  800  via communication bus  702 . For example, navigation system  94  is activated by receiving the power from battery  132  in response to the reception of the activation signal. At this time, navigation system  94  displays the state of charge of battery  132  charged by external charging device  1000 . 
     After PM-ECU  600  turns on HV+PLG power supply relay  604 , it inhibits the data transfer at gateway  606  between communication buses  702  and  802  (S 304 ). Thereby, the activation of the electric devices not related to the charging is suppressed. 
     PM-ECU  600  implements the load control corresponding to the external charging (S 306 ). When the plug connection signal is not received (NO in S 300 ), it will be on standby until a predetermined time elapses (S 308 ). 
     Referring to  FIG. 12 , description will be given on the control structure of the program executed by control device  300  of the vehicle according to the embodiment. By executing the program, control device  300  implements the end control sequence of the electric devices at the time of disconnection of charge cable  1020 . 
     In S 400 , PM-ECU  600  determines whether plug  1040  of charge cable  1020  is disconnected from socket  160  or not. More specifically, when PM-ECU  600  enters the state in which it does not receive the plug connection signal from coupling determination sensor  180 , PM-ECU  600  determines that plug  1040  is disconnected. When the state in which PM-ECU  600  receives the plug connection signal is kept, it determines that plug  1040  is not disconnected. When PM-ECU  600  determines that plug  1040  is disconnected from socket  160  (YES in S 400 ), the process proceeds to S 404 . Otherwise (NO in S 400 ), the process returns to S 400 . 
     In S 402 , PM-ECU  600  determines whether the charging of battery  130  is completed or not. When it determines that the charging is completed (YES in S 402 ), the process proceeds to S 404 . Otherwise (NO in S 402 ), the process returns to S 400 . 
     In S 404 , PM-ECU  600  turns off HV+PLG power supply relay  604 . At this time, PM-ECU  600  turns off the electric devices that were activated when plug  1040  was connected to socket  160  and HV+PLG power supply relay  604  is turned on. 
     Based on the structure and flowchart described above, control device  300  of the vehicle according to the embodiment performs the operation corresponding to the end control sequence as described below. 
     It is assumed that plug  1040  of charge cable  1020  is connected to socket  160 . When the state in which plug  1040  is connected to socket  160  is kept (NO in S 400 ) and it is determined that the charging of battery  130  is completed (YES in S 402 ), HV+PLG power supply relay  604  is turned off (S 404 ). When plug  1040  is disconnected from socket  160  (YES in S 400 ), HV+PLG power supply relay  604  is turned off (S 404 ). 
     In addition to the effect offered by the control device for the vehicle according to the first embodiment, the control device for the vehicle according to the second embodiment can operate such that the power supply states of the group of electric devices related to the charging by the external charging device are collectively set by the HV+PLG power supply relay to the state for supplying the power and the state not supplying it, as described above, Therefore, as compared with the case where an independent relay of the like is arranged for each electric device, it is possible to suppress the increase in mass, and it is possible to prevent deterioration in mountability of other parts on the vehicle that may be caused by provision of the plurality of relays. Accordingly, the space for mounting the electric devices can be ensured. 
     In addition to the load control, the second embodiment may be configured to change the set voltage of the DC-DC converter, as is done in the control device for the vehicle of the first embodiment already described. Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the scope of the present invention being interpreted by the terms of the appended claims.