Abstract:
A method for calibrating a vehicle system having multiple interconnected components including an electronic control unit, the method including the attachment of an unpowered, semiconductor-based transponder unit that responds to a radio signal to each component of the system, the encoding of the transponder unit with data pertaining to the component, the excitation of the transponder unit using a radio scanner in order to read the data of the transponder unit and the writing of data into the electronic control unit after the component has been installed in the vehicle system.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   The present application is the U.S. national stage application pursuant to 35 U.S.C. §371 of International Application No. PCT/DE02/04077 filed Nov. 2, 2002, which application claims benefit of United Kingdom Patent Application No. 0127067.7, filed Nov. 10, 2001. 
   BACKGROUND OF THE INVENTION 
   The present invention relates to vehicle systems, for example, an automated transmission system or an automated gear shift system for a motor vehicle. 
   Automated transmission systems for motor vehicles, such as in British Patents 2308413, 2354296, 2354295, 2358443, 0105186.1, 0029453.8, 0026423.4, 0025848.3, 0025847.5, 0029454.6, 0025000.1, 0024999.5, 0026178.4, 0027640.2, 0028310.1, 0031624.0, 0103312.5, whose content is expressly incorporated in the disclosure content of the present invention, include various components, for example an hydraulic pressure supply unit, a valve unit, a gear shift mechanism and an electronic control unit, which are installed in the vehicle either as original equipment or as upgrades and even as spare parts installed during maintenance of the vehicles. 
   In order to function correctly, the various components for the system must be calibrated, and the electronic control unit must be programmed using the important identifiers of the components. This may be performed after installation of the system in the vehicle. However, it is desirable for individual components to be pre-calibrated by means of bench tests and the identifier of each component to be entered in the control unit when the system is installed or when a component in the system is replaced. 
   It is also desirable for each component of the system to be identified to ensure that the correct part is installed in the system and to offer protection from imitation parts. 
   Bar coding of the various components of the system has previously been used for this purpose, the various bar codes being read using a scanner when the system is installed in the vehicle and the data being entered in the electronic control unit. 
   This method of marking the various components of the system has the disadvantage that the bar code must be visible so it is possible to scan them. This is not always possible when the system is installed in the vehicle. Moreover, it is easy for the bar codes to be covered with dirt or to detach from the components. 
   The present invention provides an improved method for calibrating such systems. 
   According to one aspect of the present invention, a method for calibrating a vehicle system comprising multiple interconnected components, among them an electronic control unit, includes the attachment to each component of the system of an unpowered, semiconductor-based electronic transponder unit that responds to a radio signal, encoding of the transponder unit with data that pertains to the component, and excitation of the transponder unit using a radio scanner to read the data from the transponder unit and write the data into the electronic control unit after the component has been installed in the vehicle system. 
   Using the electronic marking means according to the present invention, the radio scanner only needs to be disposed in the vicinity of the transducer in order to read the data and thereby overcomes the difficulty of reading data from unfavorably positioned components. Furthermore, the transponders may also be read, even if they are heavily soiled. Electronic, semiconductor-based transponders of the type used are also capable of storing more data than are able to be represented in a bar code. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is then described, only as an example, with reference to the accompanying drawings, of which: 
       FIG. 1  diagrammatically shows a semi-automatic transmission system of a motor vehicle; 
       FIG. 2  shows a gear shift mechanism and the associated selection gate of the transmission system that is represented in  FIG. 1 ; 
       FIG. 3  diagrammatically shows the hydraulic actuation system of the transmission system represented in  FIG. 1 ; 
       FIG. 4  shows a diagrammatic cross-sectional view of the main control valve of the hydraulic actuation system represented in  FIG. 3  in an excited second position; 
       FIG. 5  shows a view similar to  FIG. 4  of the main control valve in an excited third position; 
       FIG. 6  shows a view similar to  FIG. 4  of the main control valve in an excited fourth position; 
       FIG. 7  shows a diagrammatic cross-sectional view of the gear shift control valve of the hydraulic actuation system represented in  FIG. 3  in an excited third position; 
       FIG. 8  shows a view similar to  FIG. 7  of the gear shift control valve in an excited third position; 
       FIG. 9  shows a view similar to  FIG. 7  of the gear shift control valve in an excited fourth position; and 
       FIG. 10  is a block diagram of the transmission system represented in  FIGS. 1 to 9  adapted to be calibrated according to the method of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  of the accompanying drawings shows an engine  10  having a starter and an associated starter circuit  10   a  that is coupled by the main drive friction clutch  14  via a transmission shaft  15  to a multi-speed, synchronized transmission of the type having a countershaft  12 . The engine is supplied with fuel via a throttle  16 , the throttle including a throttle slide valve  18 , that is actuated by the gas pedal  19 . The invention is equally applicable for gasoline or diesel engines having electronic or mechanical fuel injection. 
   Clutch  14  is actuated by a release fork  20 , which on its part is actuated by a hydraulic slave cylinder  22  that is controlled by the clutch actuator control means  38 . 
   A gear selection lever  24  operates in a shift gate  50  having two legs  51  and  52  that are connected by a transverse track  53 , which extends between the end of leg  52  and a position between the ends of leg  51 . Control gate  50  defines five positions: “R” at the end of leg  52 , “N” in the center between the ends of transverse track  53 , “S” at the junction point of leg  51  and transverse track  53 , and “+” and “−” at the ends of leg  51 . In leg  51  lever  24  is aligned at the outset with central position “S”. The “N” position of selection lever  24  corresponds to neutral; “R” corresponds to the selection of reverse gear; “S” corresponds to the selection of a forward drive mode; the brief movement of the lever into the “+” position represents a command that causes the transmission to shift up one gear step; and the brief movement of the gear selection lever  24  into the “−” position represents a command that causes the transmission to shift down one gear step. 
   The positions of lever  24  are detected by a series of sensors, such as microswitches or optical sensors, that are disposed around shift gate  50 . The signals of the sensors are fed to an electronic control unit  36 . An output of control unit  36  controls a gear engagement mechanism  25 , which engages the gear ratios of transmission  12  according to the movement of selection lever  24  by the driver of the vehicle. 
   In addition to the signals of gear selection lever  24 , control unit  36  receives signals from: Sensor  19   a , which indicates the degree to which gas pedal  19  is depressed; sensor  30 , which indicates the degree to which throttle control valve  18  is opened; sensor  26 , which indicates the engine speed; sensor  42 , which indicates the speed of the driven clutch plate; and sensor  34 , which indicates the position of the clutch slave cylinder. 
   Control unit  36  uses the signals of these sensors to control the actuation of clutch  14  when starting out from the idle position and when changing gears, as is described, for example, in the descriptions of European patents 0038113, 0043660, 0059035 and 0101220 and WIPO patent 092/13208, whose contents are expressly incorporated in the disclosure content of the present invention. 
   In addition to the aforementioned sensors, control unit  36  also still receives signals from a vehicle speedometer  57 , from ignition lock  54  and from brake switch  56 , which is associated with the main braking system of the vehicle, for example, foot brake  58 . 
   A buzzer  55  is connected to control unit  36  in order to warn the driver of the vehicle, or to indicate to him if certain operating conditions are occurring. In addition to or instead of buzzer  55 , a flashing warning light or other display means may be used. A gear indicator  60  is also provided to indicate the selected gear. 
   As described in  FIG. 2 , the gear engagement mechanism  25  includes three shift rails  111 ,  112 ,  113  that are mounted parallel to each other for movement in an axial direction. Each shift rail  111 ,  112 ,  113  is connected in a standard way via a shift fork and a synchronizer to two of the gear ratios of transmission  12 , so the movement of shift rails  111 ,  112 ,  113  in an axial direction causes the engagement of one of the gears and the axial movement of shift rails  111 ,  112 ,  113  in the opposite axial direction causes the engagement of the other gear. 
   Typically, first and second gear are assigned to shift rail  111 , so the axial movement of shift rail  111  in a first direction engages first gear, or the axial movement of shift rail  111  in a second direction engages second gear; third and forth gears are assigned to shift rail  112 , so the axial movement of shift rail  112  in a first direction engages third gear or the axial movement of shift rail  112  in a second direction engages fourth gear; and fifth gear and reverse are assigned to shift rail  113 , so the axial movement of shift rail  113  in the first direction engages fifth gear, while the axial movement of shift rail  113  in the second direction engages the reverse gear. 
   A selection device element  110  is mounted for a movement in a select direction X transverse to the axes of shift rails  111 ,  112 ,  113  and in a shift direction Y, which represents an axial movement with respect to shift rails  111 ,  112 , and  113 . Selection device element  110  may be moved from there in a selected direction X along a neutral plane A-B, so it may be indexed with one of shift rails  111 ,  112  and  113  and engage in a selected shift rail. Selection device element  110  may then be moved in a shift direction Y in order to move the occupied shift rail  111 ,  112 ,  113  axially in one of the two directions to engage one of the gears that are associated with them. 
   As illustrated in  FIG. 3 , selection device element  110  is movable in selected direction X by means of a first actuator  114  that is actuated by fluid pressure along neutral plane A-B, as illustrated in  FIG. 2 , in order to align selection device element  110  with one of shift rails  111 ,  112  or  113  and thereby select a gear pair that is assigned to the shift rail. Selection device element  110  may then be moved in shift direction Y by means of a fluid-pressure operated actuator  115 , in order to move shift rail  111 ,  112  or  113  axially in one of the two directions to engage one of the gears assigned thereto. 
   Actuators  114  and  115  each comprise a double-acting ram with pistons  116  and  117 , respectively, which divide the actuators into two working chambers  118 ,  119 , working chambers  118 ,  119  being disposed on opposite sides of each piston  116 ,  117 . Engagement rods  114   a ,  115   a  extend from one side of piston  116  and  117 , respectively, and are operatively connected to selection device element  110  for movement thereof in the select and shift directions X and Y, respectively. As a result of the connection of engagement rods  114   a  to X and Y, the working surface of pistons  116 ,  117 , that faces working chamber  118  is smaller than the working surface of pistons  116 ,  117  that faces working chamber  119 . 
   A solenoid-controlled main control valve  120  comprises a housing  122 , which defines a valve cylinder  124 . A piston valve  126  is disposed within valve cylinder  124  in such a manner as to be able to slide, piston valve  126  having three axially spaced surrounding ribs  128 ,  130 ,  132  that engage the valve cylinder in such a manner as to seal it. A solenoid  134  acts at one end of piston valve  126  so that when solenoid  134  is excited, piston valve  126  moves axially within valve cylinder  124  against a load that is exerted by a compression spring  136 , which on its part acts on the opposite end of piston valve  126 . 
   An inlet  138  into valve cylinder  124  of valve  120  is connected to a spring accumulator  275 . Spring accumulator  275  comprises a piston  285  that is sealed in a cylinder  286  in such a manner that it is movable. A spring  287  acts on one side of piston  285  biasing it to one end of cylinder  286 . An electrically driven pump  223  is provided in order to charge accumulator  275  via a check valve  276 , supplying fluid to the side of piston  285  that is away from spring  287 , whereupon spring  287  is compressed and the fluid is placed under pressure. The side of piston  285  from which spring  287  acts is vented and serves as a fluid equalizing vessel  278  for the system. A pressure transducer  282  is provided between spring accumulator  275  and inlet  138  of main valve  120  in order to measure the accumulator pressure and transmit signals corresponding to the pressure to control unit  36 . 
   An outlet  140  from valve cylinder  124  is connected to equalizing vessel  278 . A first opening  142  of valve cylinder  124  is connected to working chambers  118  of select and shift actuators  114 ,  115  and selectively connected to working chambers  119  via select and shift valves  144 ,  146 , and a second opening  148  is connected to clutch slave cylinder  22 . A pressure relief valve  280  is provided between the outlet of pump  223  and equalizing vessel  278  in order to ensure that the pressure that is supplied by pump  223  does not exceed a maximum predetermined value. 
   Select and shift valves  144 ,  146  are both solenoid-controlled valves, each of which has a housing  150  by which a valve cylinder  151  is defined having a piston valve  152  that is installed in valve cylinder  151  such a manner as to be able to slide. Piston valve  152  has three axially spaced ribs  154 ,  156 ,  158 , the ribs engaging with valve cylinder  151  in such a manner as to seal it. An axial bore  160  opens at end  162  of piston valve  152  and provides the connection to a transverse bore  164 , transverse bore  164  opening between ribs  154  and  156  of piston valve  152 . A solenoid  166  acts on an end  168  of piston valve  152  that is away from end  162  so that, upon excitation of solenoid  166 , piston valve  152  moves axially within valve cylinder  151  against a load that is exerted by a compression spring  170 , which on its part acts on end  162  of piston valve  152 . 
   An inlet  172  of valve cylinder  151  is connected to opening  142  of main control valve  120 . An outlet  174  from valve cylinder  151  is connected to equalizing vessel  278 . Opening  178  of select valve  144  is connected to second working chamber  119  of select actuator  114 , and opening  178  of shift valve  146  is connected to second working chamber  119  of shift actuator  115 . 
   The structure and operation of valves  144  and  146  and actuator  114  and  115  are identical to that which is represented in  FIGS. 7 to 9 . 
   If the transmission is engaged in a gear and clutch  14  is engaged, solenoids  134  and  166  are not excited, and valves  120 ,  144  and  146  are in the idle positions that are represented in  FIG. 3 . In this position, clutch slave cylinder  22  is connected via opening  148  and outlet  140  of main control valve  120  to equalizing vessel  278 ; working chambers  118  of select and shift actuators  114 ,  115  are connected to equalizing vessel  278  via inlet  172 , ports  164 ,  160  and outlet  174  of select and shift valves  144 ,  146 ; and working chambers  119  of select and shift actuators  114 ,  115  are connected to equalizing vessel  278  via opening  178  and outlet  174  of select and shift valves  144 ,  146 . Consequently, there is a movement neither of clutch slave cylinder  22  nor of select and shift actuators  114 ,  115 . 
   If a gear change is initiated, for example, by the driver of the vehicle moving gear selection lever  24  for a moment into the “+” position, or by automatic initiation, solenoid  134  is excited in order to move piston valve  126  of main control valve  120  into a second position, as illustrated in  FIG. 4 . In this second position, working chambers  118  of both the select and shift actuators  114 ,  115  and inlets  172  of both select and shift valves  144 ,  146  are connected to spring accumulator  275  via opening  142  and inlet  138 . In this second position, clutch slave cylinder  22  is connected to equalizing vessel  278 . 
   Simultaneously with the excitation of solenoid  134 , in order to move main control valve  120  into the second position represented in  FIG. 4 , solenoids  166  of select and shift valves  144 ,  146  are excited in order to move piston valve  152  into a zero position, as represented in  FIG. 7 . In this second position, rib  158  of piston valve  152  closes opening  178 , whereupon working chamber  119  is closed and an hydraulic lock is developed that hinders the movement of select and shift actuators  114  and  115 , although working chambers  118  thereof are connected to spring accumulator  275  via main control valve  120 . The connection of opening  172  to outlet  174  via valve cylinder  160  and  164  is also closed. 
   Another excitation of solenoid  134  into a third position, as represented in  FIG. 5 , then closes the connection between the clutch slave cylinder and the equalizing vessel and opens the connection between the clutch slave cylinder and spring accumulator  275 , release fork  20  being actuated to disengage clutch  14 . 
   When clutch  14  is disengaged, solenoid  134  of main control valve  120  may be excited in order to move the main control valve back into the fourth position, as illustrated in  FIG. 6 . In this fourth position, opening  148  is separated from inlet  138  and outlet  140 , so clutch  14  is held firmly in the disengaged position. Solenoids  166  of the select and shift valves  144 ,  146  may then be selectively excited, select and shift valves  144 ,  146  being moved between the third and fourth positions in order to disengage the gear that is selected at this moment and engage a new gear. 
   The excitation of solenoid  166  to move select and shift valve  144 ,  146  into a third position, as illustrated in  FIG. 8 , in which working chamber  119  is connected to equalizing vessel  278  while working chamber  118  is connected to accumulator  275 , creates a pressure differential across pistons  116  and  117  that causes engagement rods  114   a ,  115   a  to extend. The excitation of solenoid  166  to move select and shift valve  144 ,  146  into the fourth position, as represented in  FIG. 9 , in which both working chambers  118  and  119  are connected to spring accumulator  275 , causes engagement rods  114   a ,  115   a  to retract because of the different working surfaces of pistons  116  and  117 . Consequently, selection device element  110  may be moved by suitable control solenoids  166  of select and shift valves  144 ,  146  in order to engage the desired gear. 
   Potentiometers  226  and  227  are connected to engagement rods  114   a  or  115   a , respectively, in order to provide signals that designate the position of the associated engagement rods. The signals of potentiometers  226  and  227  are fed to control unit  36  in order to provide an indication of the position of engagement rods  114   a  and  115   a  for each of the gear ratios of transmission  12  and also to designate the position of engagement rods  115   a  when selection device element  110  is located in neutral plane A-B from  FIG. 2 . The transmission system may thus be calibrated so predetermined position signals that come from potentiometers  226  and  227  correspond to the engagement of each of the gears of transmission  12 . 
   Measurements of potentiometers  226  and  227  may therefore be used by a closed loop control system to control valves  144  and  146  in order to move engagement rods  114   a  and  115   a  to the predetermined positions to engage the desired gear. 
   When the desired gear has been engaged, solenoids  166  of select and shift valves  144 ,  146  are excited in order to move valves  144 ,  146  back into their zero positions, openings  178  being closed and a hydraulic locking being produced that prevents a movement of actuators  114 ,  115 . 
   Solenoid  134  of main control valve  120  may then be excited in order to move main control valve  120  out of its fourth position into its second position, whereupon fluid may be conducted back from clutch slave cylinder  22  into equalizing vessel  278 , which enables re-engagement of clutch  14 . Main control valve  120  may be switched between the third and second position so clutch  14  is re-engaged in a controlled manner, for example, as disclosed in European patents 0038113; 0043660; 0059035; 0101220 or WIPO patent 92/13208. 
   When clutch  14  has been re-engaged, solenoid  134  of main control valve  120  may be de-energized, so it returns to the idle position that is illustrated in  FIG. 3 . Solenoids  166  of select and shift valves  144 ,  146  may be de-energized in a similar manner. The movement of select and shift valves  144 ,  146  into the idle position, which is illustrated in  FIG. 3 , opens working chamber  119  to equalizing vessel  278 , whereupon the pressure built up therein is relieved. 
   As illustrated in  FIG. 10 , accumulator  275 , equalizing vessel  278 , pump  223 , check valve  276 , pressure relief valve  280  and pressure sensor  282  are typically accommodated together within a common housing as an hydraulic power unit  300 , which may be disposed at a distance from the vehicle engine where the environment is less harsh and the components are more accessible. Gear engagement actuators  114 ,  115  and gear engagement control valves  144 ,  146  are also typically joined within a common housing as a gear engagement actuator unit  302 , which may be attached to transmission  12 . Electronic control unit  36  may form a part of the hydraulic power unit or, alternatively, may represent an independent component of the system. 
   Control unit  36  is electrically connected to hydraulic power unit  300 , gear engagement actuator unit  302  and clutch actuator  22 , so suitable control signals may be transmitted between the different units and electronic control unit  36  in order to control, for example, the operation of pump  223 , main control valve  120  and gear engagement valves  144 ,  146  and to receive response messages from the different sensors  282 ,  226 ,  227  that are associated with components  120 ,  114 ,  115 . 
   Furthermore, control unit  36  is also connected via vehicle CAN bus  304  to the electronic control units of other systems of the vehicle, for example, to engine management control unit  306  and brake control unit  308 . In this way, electronic control unit  36  is able to transmit signals to engine management control unit  306  in order to control engine speed when starting out from the idle phase and when changing gears and also in order to receive signals from engine management control unit  306 , which provides information about the throttle position, engine speed, etc. Electronic control unit  36  may also receive signals from brake management control unit  308  from the wheel speed sensors that are related to the speed of the vehicle. 
   As illustrated in  FIG. 10 , each unit  300 ,  302 ,  36 ,  22  that comprises the transmission system has an unpowered, semiconductor-based transponder unit  310 , which is embedded in unit  300 ,  302 ,  36 ,  22 . Where units  300 ,  302 ,  36 ,  22  have parts that are made out of plastic, for example housings or covers, transponder units  310  may be set into these parts. Alternatively, transponder units  310  may be disposed in recesses that are configured in a housing of components  300 ,  302 ,  36 ,  22  and cast therein using a suitable heat-resistant or chemically resistant mixture. 
   Transponder units  310  are typically semiconductor components that are connected to an RF antenna and a tuning capacitor and sealed in a capsule. The semiconductor components are able to store an alphanumeric code comprising 10 to 15 positions and respond to a radio signal of a scanner  312  in order to transmit the alphanumeric code that was picked up from scanner  312 . When encoding in the hexadecimal system, a ten-place alphanumeric code provides a quantity of 160 bits, and, when encoding using the complete United Kingdom alphabet, there are 360 bits that may be assigned in groups to represent values that corresponds to the varying identification information and operating parameters of various units  300 ,  302 ,  36 ,  22 . 
   For example: 
   
     
       
             
             
             
           
         
             
                 
             
           
           
             
               Bits 
                0–3 
               may provide a value that identifies the unit as, for example, 
             
             
                 
                 
               a control unit (36), an hydraulic power unit (300) or a gear 
             
             
                 
                 
               engagement control unit (302); 
             
             
                 
                6–4 
               the production week number; 
             
             
                 
                8–7 
               weekday; 
             
             
                 
               12–9 
               positions/equipment number ID. 
             
             
                 
             
           
        
       
     
   
   This information may be used in order to confirm that the correct unit  300 ,  302 ,  36 ,  22  was installed in the system and the unit  300 ,  302 ,  36 ,  22  is an original and not an imitation. 
   Moreover, the semiconductor component may be encoded with information that relates to the operating parameters of units  300 ,  302 ,  36 ,  22  to which they are attached. While the various units  300 ,  302 ,  36 ,  22  are being produced in order to provide prescribed nominal operating features, these parameters will differ from unit to unit based on manufacturing tolerances. To optimize the operation of the transmission system, it is necessary to measure these parameters and to program control unit  36  with the measured parameters. This can be done at the end of the assembly line when the transmission system has been installed in the vehicle. However, this creates problems related to accuracy and quality control. 
   Using the method that is covered by the present invention, each unit  300 ,  302 ,  36 ,  22  of the transmission control system may be tested on the test bench after it has been assembled and transponder unit  310  has been encoded with information related to the operating parameters. 
   For example, for hydraulic power unit  300 , transponder unit  310  may be encoded with values that correspond to the following parameters: 
   
     
       
             
             
             
             
           
         
             
                 
                 
             
           
           
             
                 
               Bits 
               29–13 
               Operating pressure of pressure relief valve; 
             
             
                 
                 
               24–21 
               Zero current of the main control valve solenoid; 
             
             
                 
                 
               28–25 
               Minimum charge pressure of the accumulator; 
             
             
                 
                 
               32–29 
               Pressure sensor calibration factor; 
             
             
                 
                 
               36–33 
               Pump capacity; etc. 
             
             
                 
                 
             
           
        
       
     
   
   In addition to the unit identification and the operating data, when units  300 ,  302 ,  36 ,  22  are installed in the vehicle, transponder units  310  may also be encoded for security purposes with vehicle information data, for example of the VI numbers. 
   After installation of the various units  300 ,  302 ,  36 ,  22  in a vehicle, transponder units  310  of the various units  300 ,  302 ,  36 ,  22  may be scanned using a hand-held radio scanner  312 , which excites transponder units  310  and reads the codes that are transmitted by transponder units  310 . This enables accurately checking that the correct units  300 ,  302 ,  36 ,  22  have been installed in the vehicle. Moreover, hand-held radio scanner  312  are connected to vehicle CAN bus  304  so that the critical operating parameters of the various units  300 ,  302 ,  36 ,  22  may be written directly into the electronic control unit  36  via vehicle CAN bus  304 . 
   The method of the present invention in further processing allows effective programming of electronic control unit  36  after the installation of the system in a vehicle or the recalibration of electronic control unit  36  if a unit  300 ,  302 ,  36 ,  22  of the system is replaced during maintenance of the vehicle. 
   While the invention has been described with reference to a motor vehicle transmission system, the invention is of course applicable to other vehicle systems, which include a number of units, an electronic control unit being among them, and which must be put together to form a system, for example, the engine management control system or brake control system. 
   The patent claims submitted along with the application are formulation proposals without prejudice for the attainment of further patent protection. The applicant reserves the right to claim additional feature combinations that so far are only disclosed in the description and/or drawings. 
   References used in the dependent claims point to the further development of the subject matter of the main claim by the features of each dependent claim; they are not to be understood as renunciation of the attainment of a separate, concrete protection for the feature combinations of the referred dependent claims. 
   Because the subject matter of the dependent claims may form separate and independent inventions with respect to the state of the art on the priority date, the applicant reserves the right to make them the subject matter of independent claims or separation statements. They may furthermore also include independent inventions that have a configuration independent of the subject matter of prior dependent claims. 
   The exemplary embodiments are not to be understood as a limitation of the invention. Rather, numerous amendments and modifications are possible within the context of the present publication, especially such variants, elements and combinations and/or materials as may be inferred by one skilled in the art with regard to the resolution of the problem using, for example, a combination or modification of individual features or elements or methodological steps that are described in connection with the general description and embodiments as well as the claims and that are contained in the drawings and, using combinable features, lead to a new subject matter or to new methodological steps or methodological sequences, even if they pertain to manufacturing, testing and operating method.