Abstract:
A procedure for the control and regulation of a clutch of an automatic stepless transmission for a motor vehicle in which an electronic control device, via a first or second regulation circuit, determines the behavior of the clutch during three driving conditions and wherein a stepless gear ratio change is carried out from a first into a second gear ratio. In accord with the invention, for the control and the regulation of the clutch during the first driving condition, the first regulation circuit is employed, the size of the regulation thereof being equivalent to the actual value of the motor speed of rotation (n_MOT_IST). During the second driving condition, a second regulating circuit is employed, the size of the regulation thereof being equivalent to the actual value of a difference in speeds of rotation (dnK_IST) of the clutch and during the third driving condition, the clutch is subjected to a controlled pressure value dependent upon various value influences.

Description:
FIELD OF THE INVENTION 
     The invention concerns a procedure for control and adjustment of a clutch in a stepless, automatic transmission in which an electronic control apparatus with two regulation circuits determines the adjustment of the clutch. The invention further concerns an apparatus for the execution of the procedure for the control and adjustment of a clutch in a motor vehicle transmission. 
     BACKGROUND OF THE INVENTION 
     By the term, “clutch”, within the concept of the invention, it is to be understood that a “start-up” clutch is meant. Under this classification are to be found clutches which are positioned between an internal combustion motor and an automatic transmission, also torque converter, bypass clutches as well as such clutches and brakes in automatic transmissions which can be employed both for start-up and for shifting. 
     In particular, the invention concerns wet start-up clutches which can be integrated into an automatic transmission. The majority of such clutches, however, are installed as a component assembly on the input side of the transmission. However, as a start-up element for an automatic stepless transmission, especially in a CVT, these wet clutches are also placed as a component assembly on the output side of the transmission. 
     Normally, clutches and brakes in automatic transmissions or in automatic stepped transmissions are electro-hydraulically activated, and operate independently of intervention by the shifting elements. The said clutches and brakes then perform as a gear position shifting means, or as gear change clutches in an assembly, or start-up clutches or yet as converter bypass clutches. To enable this service, usually an electronic transmission control apparatus acts specifically for an individual vehicle, while processing transmission and driving demands which are dependent upon the driving condition. These specifics can include axle gear ratios, transmission gear ratios, motor torque, motor rotation speed, throttle pedal position, or the like. The acquired data, as input, is processed in an electronic control apparatus and, by means of actuators and hydraulic valves, then converted into hydraulic control pressures designated for corresponding clutches. This latter data input would include clutch related signals, such as pressure control for pressure regulation or pressures during a gear change, and/or speed of rotation control during slip operation, all of which are transmitted to a hydraulic control apparatus and by means of actuators and hydraulic valves care converted to hydraulic control pressures for the corresponding clutch. 
     A procedure for the control of a start-up clutch, along with other matters, has been made known by DE 44 09 122 A1. The start-up control comprises, in this case, two phases. In a first phase, the input speed of rotation of the clutch is directed to a set-speed of rotation, wherein this set speed of rotation is determined by the driver&#39;s demand for power and a current mode of driving is determined. In the second phase, the difference between the input side and the output side speeds of rotation of the clutch is reduced to a set value of zero. 
     DE 39 37 976 discloses a procedure for the control of a clutch which serves for clutch non-interaction due to vibration disturbance. The slippage in the clutch changes, in this case, and is dependent upon speed-of-rotation-equalization as determined at the transmission output. 
     EP 0 214 989 B2 again makes known the use of a clutch integrated in an automatic transmission as a start-up element. 
     DE 198 40 573, of the applicant which up to now has not been published, describes a procedure for the control and regulation of a clutch in a stepless, automatic transmission for a motor vehicle according to which, the clutch control and regulation occurs during two driving conditions by means of a first control circuit. The degree of this control corresponds to the actual value of a difference in speed of rotation of the clutch. The first condition corresponds to a start-up process and the second condition corresponds to driving with a variable ratio arrangement. 
     From the likewise non-published DE 198 40 572 of the Applicant, a process for the control and regulation of a clutch in an automatic stepped transmission with traction interruption, that is to say, in an automatic stepped transmission which can shift in accord with the load is made known. With this method, during three conditions of driving (enumerated below), control is effected by means of a first regulating circuit. The degree of regulation, or-control, corresponds to the actual value of a difference in speeds of rotation of the clutch. The first condition of driving relates to a start-up process. The second condition of driving pertains to driving with a constant gear ratio. The third condition comes into play when load shifting, that is to say, a change of the ratio is initiated by a first into a second gear step of the automatic drive. 
     SUMMARY OF THE INVENTION 
     Given the above description of the state of the technology, the present invention has the purpose of making available a procedure for the control and regulation of a clutch in a stepless transmission for a motor vehicle along with an apparatus for the execution of said procedure for the control and regulation of a clutch, and to further develop the same with consideration given to the manifold usages of a single clutch, especially to achieve an improved quality of regulation and control-dynamics, in connection with an automatic stepped-transmission. 
     The object of the invention is to be found advantageously therein in that, during the first condition of driving, a first regulation circuit is employed for the control and regulation of the clutch. The degree of regulation corresponds to the actual value of the speed of rotation of the motor n_MOT_IST and corresponds to the input speed of rotation of the clutch. During the second condition of driving, a second regulating circuit is used, the degree of regulation being equivalent to the actual value of the difference in rotational speeds of the clutch dnK_IST. Finally, during the third condition of driving, the clutch is subjected to controlled values of pressure which, in turn, are influenced by various factors. The three conditions of driving correspond, in the above, to a first condition comprising a start-up procedure when under a threshold vehicle driving speed during a traction operation, a second condition marked by driving the vehicle at a speed above the start-up procedure, i.e., above a threshold driving speed with a positive or a negative torque during a traction or a compression mode, as well as driving under a vehicle threshold speed with negative torque at the output, and a third condition, wherein the start-up condition differentiates itself from the other driving conditions in that the driving speed is less than a threshold value and the vehicle motor can stall under this said threshold value. 
     By means of the procedure in accord with the invention, a better reaction of the transmission control advantageously is achieved in regard to load shifting, especially upon letting up on the fuel feed in the third condition since, in this case, the control still performs an empty action upon the pressure at the clutch although no adjustment takes place. 
     Further, the difference in speeds of rotation over the clutch is not brought back to a value of zero. The advantageous consequence of this is that a non-interaction vibration between the motor and the transmission is achieved. 
     In an advantageous development of the invention, the proposal is made that the change in gear ratio in a stepless automatic transmission is principally determined by a third regulating circuit, and that the first and third, or second and third regulating circuits are bound together by means of a non-interacting network, which exhibits a first and a second signal path, respectively. More advantageously, it is proposed here, that for the change of the ratio from a first to a second gear ratio, an individual regulating circuit is employed, namely, the third circuit. 
     For this case, as for the situation during the ratio-change, the two regulating circuits, which find themselves in action, are bound to one another by a non-interacting network which advantageously allows that these two said regulating circuits do not interfere with one another during their functioning. 
     The proposal extends itself further in that during a gear ratio change from a first to a second gear ratio, the automatic transmission, during the first condition of driving, the first regulating circuit, by means of the non-interacting network, influences the third regulating circuit by means of a first signal path and in that the third regulating circuit, by a non-interacting means of the non-interaction network via a second regulation circuit, acts on the first regulation circuit. 
     In the case of a ratio change from a first to a second gear ratio during the second driving condition, the second regulating circuit acts by means of the non-interacting network, by way of the first signal path, on the third regulating circuit. At the same time the third regulating circuit acts, by means of the non-interacting circuit through a second signal path on the second regulating circuit. 
     In a development of the invention, the proposal is made to calculate the pressure level pAK of the clutch from an offset value pAK_OFF and a cumulative value pSUM. The cumulative value PSUM is principally determined by the sum of the controlled torque MK(ST) of the clutch, the regulated summated torque MK(RE)′ of the clutch, and the disengaged load shift torque MLS_ENT. 
     The controlled torque MK(ST) is principally derived from the dynamic torque of the clutch, i.e., MDYN_K and the motor torque MMOT. 
     The regulated summated torque MK(RE)′ of the clutch is determined from the dynamic motor torque MDYN_MOT and a regulated torque MK(RE). 
     The regulated torque MK(RE) in the first condition of driving is principally computed from set/actual comparison of one of the motor speeds of rotation n_MOT equivalent values and a load specific signal DKI of a driver by a device for increasing or decreasing the load. 
     The gear-ratio-dependent set difference in speeds of rotation dn_SW(i) for a start-up gear stage of the automatic transmission is determined, in the second condition of driving, by means of a characteristic field KF(i). This characteristic curve presents an arrangement of load specific signals of the driver DKI and an output speed of rotation nAB of the clutch. 
     The regulated torque in the second condition of driving MK(RE) is principally drawn out of the set/actual comparison of the speeds of rotation difference dnK_SW, dnK_IST of the clutch and a load specific signal initiated by a driver by a device for increasing or decreasing the load. 
     Advantageously the regulator contains a limited integrator, to which is fed as input the deviation from regulation from the set/actual comparison of the rotational speeds dnK_SW, dnK_IST of the clutch, the displacement speed of the load signal DKI and the relation of the actual to set values of the difference in rotational speeds, i.e., dnK_IST/dnK_SW of the clutch. 
     The set value of the difference in speed of rotation of the clutch dnK_SW advantageously arises from the addition of a set-value-offset dnLS_SW and a gear ratio dependent difference in rotational speed at the clutch dn_SW(i). 
     Advantageously, in the case of a transition from the first or third condition of driving to the second condition of driving, the set value of the difference in rotational speeds dnK_SW is conducted through a filter, this especially being a dynamic delay member, whereby, as the starting value of the delay member is set at the actual value of the difference in speeds of rotation, namely, dnK_IST. 
     In the second condition, there is an increase in the set value offset of the difference in speeds of rotation, dnLS_SW of the clutch, during a gear ratio change from a first into a second gear ratio stage of the automatic transmission. 
     The characteristic fields are here so formulated, that, at a vehicle speed v less than a threshold value GW, an increased difference in the speeds of rotation dn_SW(i) of the clutch arises. By this action, an effective prevention of stalling during non-start-up gear positions, that is, for example, while driving at a constant ratio of the automatic transmission is achieved. 
     Advantageously, also in the second condition of driving, at a vehicle speed v less a threshold value GW, an increased difference in speeds of rotation dn_SW(i) of the clutch is considered to be a deterrent to stalling. When this is done, the increased difference in rotational speeds dn_SW(i) is input as larger than the difference from the most minimal speed of rotation of the internal combustion motor nMOT_MIN and the output speed of rotation nAB of the clutch. 
     In the third condition of driving, the pressure level pAK of the clutch arises from a pressure value, which is dependent upon one or several of the following values: throttle flap position; brake activity; brake pressure; motor torque and load shifting or the like, and wherein the pressure value is a controlled value. 
     More advantageously, an apparatus is made available for the execution of a procedure for the control and regulation of a clutch in a stepless automatic transmission for a motor vehicle. This apparatus provides an electronic control system with a first and a second regulating circuit, whereby the degree of regulation of the first regulating circuit is equivalent to the actual value of the motor speed of rotation and the degree of regulation of the second regulation circuit is equivalent to-the actual value of a difference in speeds of rotation at the clutch. 
     Furthermore, a third circuit of regulation is provided which is connected with the first and the second circuits of regulation through a non-interacting net work, and wherein the third regulating circuit determines the load shifting. 
     Further the non-interacting network exhibits a first and a second signal path, respectively, between the first and the third regulation circuit and also between the second and the third regulation circuit. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described, by way of example, with reference to the accompanying drawings in which: 
     FIG. 1 is a general overview of the first and second regulating circuits; 
     FIG. 2 is a function block diagram  5  of set value signals; 
     FIG. 3 is a function block  6  of the regulator; and 
     FIG. 4 is a characteristic field for non-start-up gear ratios. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a panoramic overview of the two regulation circuits. Reference number  3  denotes the first regulation circuit for control and regulation of clutch  2 . Reference number  4  identifies the second regulation circuit for control and regulation of a stepless transmission. A variator is depicted in FIG. 1 by the reference number  33 . 
     As to clutch  2 , it is to be understood, in keeping with the invention, that a start-up clutch is referred to. This can be located on the input side of the stepless 
     Both the first, as well as the second regulation circuits  3 ,  4  are supplied by  17  with signal data. The input data from  17  comprises the signal of a load demand from the driver this being severally, the throttle flap data DKI, or its gradient, the torque of an internal combustion motor (not shown), which drives the stepless transmission  1 , and the input/output rotational speeds of the clutch  2 . The first regulation circuit comprises the blocks: set value signal  5 , regulator  6 , factor  7 , weight ratio  8 , absolute value  9  and constant  10 . The set value signal  5  delivers as output values, the set value of the difference of the speeds of rotation dnK_SW of the clutch  2  and the controlled torque MK(ST) of the clutch  2  as well as the dynamic motor torque MDYN_MOT. The inner structure of the set value signal  5  is explained in connection with FIG.  2 . At the regulator  6 , lie the input values  17 , the regulator set value as well as the actual values. In the first condition, the regulator set value represents the motor set value of speed of rotation n_MOT_SW and the actual value of the motor speed of rotation n_MOT_IST. In the second condition, the regulator set value represents the set difference of speeds of rotation at the clutch  2  dnK_SW and the actual value of the actual difference in speed of rotation at the clutch  2  dnK_IST. The inner structure of the regulator  6  is explained below in connection with FIG.  3 . The output values of the regulator  6  is the regulated motor torque MK(RE) of the clutch  2 . From the regulated torque MK(RE)′ of the clutch  2  and from the dynamic motor torque MDYB_MOT the regulated cumulative torque MK(RE)′ is derived at summation point A. At summation point B, this amount will be added to the controlled torque MK(ST) which is derived from the set value signal  5  of the clutch  2  and the non-interacting torque M_CVT of the stepless transmission. From this sum, the absolute value is formed, by means of the function block  9 , and the result is weighted with a constant by function block  10 . The output value is a summated pressure pSUM. A pressure offset pAK_OFF is superimposed onto this summated pressure pSUM, at summation point C. The pressure level which is evolved therefrom, namely pAK, is the effective pressure acting upon the clutch  2 . The second regulation circuit  4  comprises: set value signal  11 , regulator  12 , factor  13 , weight ratio  14  and the product of motor inertial torque times the factor  13 . The second regulation circuit  4  determines the running of the stepless change. From the input values  17 , the function block set value signal  11  determines the set value n_SW of the stepless change, and the controlled portion of the set value of the stepless transmission Y_ST. The set value n_SW is compared with the actual value n_IST of the stepless change at the summation point D. The actual value n_IST arises from the output values of the stepless transmission  1 . The regulation deviation, which generates itself is the input value of the regulator  12 . The regulator output value Y_RG is added to the dynamic torque portion Y_MDYN, from the set value signal  11 , at the summation point E. From this the regulated portion Y_(RE)′ arises. This is added to the controlled portion Y_ST and to the disengaged portion Y_ENT at the summation point F. From this sum, an actuating variable value for the stepless transmission is formed. The result is the actuating variable Y_GES for the variator  33 . 
     The first and second regulatory circuits  3 ,  4  are bound together through a non-interacting network The non-interacting network contains a first signal path, in which the function block  7  and the function block  8  are placed. The input value of the first signal path is the regulated cumulative torque MK(RE)′. This is multiplied by a factor, namely function block  7 . This factor is empirically adjusted. The result of this operation, in function block  8 , is biased with the weight ratio of the motor weight to the weight of the transmission. The output value, on this account, is then the non-interacting part Y-ENT of the clutch  2 . The second signal path of the non-interacting network possesses the function blocks  13  and  14 , the input values of which make up the regulated portion Y_(RE)′ of the stepless shift. The output value of the second signal path is the non-interacting torque of the stepless ratio M_ENT. 
     The inner structure of the set-value signal  5  shown in FIG.  2  and the described input signals from  17  are directed thereto. In the function block  18 , termed, “Set value management”, the input value of the speed of rotation of the internal combustion motor, throttle flap position DKI, and the torque of the said internal combustion motor provide a rough set-value of the difference in speeds of rotation of the clutch  2 . This value is conducted to filter  19 , which is generally a PT- 1  member with a slope limitation, and is filtered at this point. One output value of the filter  19  is a set value dnk_SW which represents the difference in speeds of rotation of the clutch  2 . This set value is made available at the output port of the set value signal  5 . A second output value of the filter  19  is directed to the function block  20  which represents the input of the motor inertial torque θ-MOT and subsequently modified by a factor  23 A. The output is then the dynamic torque of the internal combustion motor MDYN_MOT. From the output speed of rotation nAB of the clutch, by means of the function block  21 , the angular speed gradient dω/dt is determined. The result is multiplied with the motor inertia torque θ-MOT and with the actual ratio of the automatic step transmission represented by “i” in the function block  22 . The product, i.e., the output value, is the dynamic torque MDYN_K at the clutch  2 . The following equation now holds true: 
     
       
           MDYN   —   K=f (θ MOT,i,i/dt,ω,dω/dt ) 
       
     
     where: 
     
       
         
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 MDYN_K: 
                 dynamic moment of clutch 
               
               
                   
                 θ-MOT: 
                 Inertial torque of internal combustion motor 
               
               
                   
                 i: 
                 actual gear ratio stage 
               
               
                   
                 d ω/dt 
                 gradient (slope) of the angular speed at clutch 
               
               
                   
                 di/dt 
                 actual gear ratio gradient (slope), and 
               
               
                   
                 ω 
                 Angular speed at clutch. 
               
               
                   
                   
               
             
          
         
       
     
     At the summation point E, this dynamic torque of the clutch  2  is combined with the torque MMOT from the internal combustion motor. This result is then added to the previously computed dynamic torque of the internal combustion motor MDYD_MOT, at the summation point F. The result thereof is weighted with a tuning factor in the function block  23 , the output magnitude of which is the controlled torque (MK(ST) of the clutch  2 . 
     In FIG. 3 is shown the inner structure of the regulator  6 . Input to the regulator  6  comprises the data from  17  as well as the set value dnK_SW, and the actual value dnK_IST, both concerning the difference of the speeds of rotation of the clutch  2 . The function block  24  forms an absolute value from the actual value dnK_IST. This absolute value is then the input value for the divider  27  and for the summation point G. At the divider  27 , the set value dnK_SW, i.e., the difference of speeds of rotation of the clutch  2 , is delivered as a second input. The resulting quotient is conducted to the function block  28 , the characteristic line of dynamic depressing. By means of this characteristic line, in the case of very small slippage amounts, for example, less than 10 revolutions, the input value of the integrator  31  is artificially increased. By this means, an additional ramplike pressure reduction is achieved. The point of application arises from the ratio of the actual to the set value of the difference in speed of rotation of the clutch  2 . The input value designated “throttle flap data” DKI is the input signal for a dT 1 -member, this being filter block  29 . The output signal of this filter is then the input signal for the characteristic line “Open Quick!”, i.e., block  30 . By means of this characteristic line, which is dependent upon the load desire of the driver, that is, the driver&#39;s selected rate of change in making a rapid gas retraction, the input value to the integrator  31  is artificially increased. By this action, an additional ramp shaped pressure reduction is achieved. The pressure reduction can be altered by the characteristic line. 
     At the summation point G, the set value dnK_SW is added to the absolute value—which was which was formed in function block  24 —of actual value of difference in rotational speeds of clutch  2 . The result of this is then conducted, in parallel, wherein one portion is runs through a function block P-part  25  and another portion runs through function block I-part  26 . The output value of the P-part  25  acts upon the summation point H. The output value of the function block  26  is conducted to the limited integrator  31 . The output value of the said limited integrator  31  now joins the P-part (i.e., the proportional portion) from function block  25  at summation point H. The result from summation point H is conducted to the function block, action factor  32 . By means of this action factor, the direction is determined, in which directional sense the actual regulated torque is to act. This is necessary for the determination of the non-interacting portion Y_ENT. 
     In FIG. 4, a gear-ratio-dependent characteristic field KH(i) is shown. By means of this field KF(i), the difference of rotational speeds dn_SW(i) is determined for non-start-up ratios of the stepless transmission. The characteristic field contains a defined zone between the limiting curves F 1  and F 2 . The limiting curve F 2  represents 0% and the limiting curve F 1  represents 100% of the throttle flap information DKI. A point C is marked on the limiting line F 1 . This excess height of the speed of rotation, value n(c) so acts, that the clutch is retained in a slipping condition, so that an active vibratory disengagement occurs. Within the characteristic curve is presented a cross-hatched area. This area serves for the protection against stalling, that is, upon small output speeds of rotation nAB the clutch  2  is biased with a defined set value of the difference in rotational speeds. The protection for stalling can also be computed by the following relationship: 
     
       
           dnK   —   SW ( i&gt;NMOT   —   MIN−nAB ) 
       
     
     where: 
     NMOT_MIN is the minimum rotational speed of the internal combustion motor; and NAB is the output speed of rotation of the clutch  2 . 
     For various zones of gear ratios, corresponding characteristic fields exist. The transition from a first KF( 1 ) to a second KF(i) is done during the change of the stepless transmission  1 . 
     The sequence of the procedure, in accord with the invention, is as follows: 
     First Condition 
     The start-up is carried out by means of regulation of the motor speed of rotation. The vehicle sets itself into motion up to a point exceeding the lower limit of the threshold of difference in rotational speeds of the clutch  2 . That is to say, after exceeding the basic speed of the transition point of the second condition. 
     Second Condition 
     Now the difference in speeds of rotation of the clutch is regulated. The set value is taken from the characteristic field corresponding to the gear ratio. In order to achieve a smooth transition, the actual differential speed of rotation dnK_IST is input to the filter installed after the set value generator as a starting value. In this way, a continuous changing of the actual difference of rotational speeds is achieved and therewith a smooth run of clutch torque is assured. 
     If now a stepless gear change is initiated, then a change is made from the characteristic field KF(i 1 ) to a characteristic field KF(i 2 ) in accord with FIG.  4 . During the stepless change, a non-interacting part M_CVT is added to controlled torque MK(ST) and regulated cumulative torque MK(RE)′ by means of the non-interacting network via the second signal path. Via the first signal path, a non-interacting part Y_ENT of the clutch  2  is added to the variator which is to make the change. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 Reference Number and Item List 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                  1 
                 stepless transmission or CVT 
               
               
                  2 
                 clutch 
               
               
                  3 
                 first regulation circuit 
               
               
                  4 
                 second regulation circuit 
               
               
                  5 
                 set value signal 
               
               
                  6 
                 regulator 
               
               
                  7 
                 factor 
               
               
                  8 
                 computation block, weight relationship 
               
               
                  9 
                 absolute value, a converter 
               
               
                 10 
                 a constant 
               
               
                 11 
                 set value signal 
               
               
                 12 
                 regulator 
               
               
                 13 
                 factor 
               
               
                 14 
                 computation block, weight relationship 
               
               
                 17 
                 input values 
               
               
                 18 
                 set value management 
               
               
                 19 
                 filter 
               
               
                 20 
                 inertial torque 
               
               
                 21 
                 computation block, i.e. dOmega/dt 
               
               
                 22 
                 computation block 
               
               
                 23, 23A 
                 factor 
               
               
                 24 
                 absolute value 
               
               
                 25 
                 P-part 
               
               
                 26 
                 I-part 
               
               
                 27 
                 divider 
               
               
                 28 
                 characteristic field, dynamic reduction 
               
               
                 29 
                 dT1-member (filter) 
               
               
                 30 
                 characteristic line (Open Quick!) 
               
               
                 31 
                 limited integrator. 
               
               
                 32 
                 action factor 
               
               
                 33 
                 variator 
               
               
                 dn_SW(i) 
                 gear ratio dependent difference in rotational speeds 
               
               
                 dnK_SW 
                 set value difference in rotational speeds at clutch 
               
               
                 dnK_IST 
                 actual value difference in rotation speeds at clutch 
               
               
                 MK(ST) 
                 controlled motor torque 
               
               
                 MK(RE) 
                 regulated torque at clutch 
               
               
                 MK(RE)′ 
                 regulated cumulative torque at clutch 
               
               
                 pAK-OFF 
                 pressure off-set start-up clutch 
               
               
                 PSUM 
                 summated pressure 
               
               
                 PAK 
                 pressure level at clutch 
               
               
                 MDYN_K 
                 dynamic torque at clutch 
               
               
                 pLS_OFF 
                 pressure off-set, load shifting 
               
               
                 nEIN 
                 input side speed or rotation at clutch 
               
               
                 nAB 
                 output side speed of rotation at clutch 
               
               
                 n_MOT_SW 
                 set value speed of rotation of motor 
               
               
                 n_MOT_IST 
                 actual speed of rotation of motor 
               
               
                 n-MOT_MIN 
                 minimal speed of rotation of internal 
               
               
                   
                 combustion motor 
               
               
                 Y_ST 
                 controlled portion of the actuating variable of 
               
               
                   
                 the variator 
               
               
                 Y_RE 
                 regulated portion of the actuating variable of 
               
               
                   
                 the variator 
               
               
                 Y_REI 
                 sum of the portions Y-RE and Y-MDYN 
               
               
                 Y_ENT 
                 non-interactive portion of the actuating variable of 
               
               
                   
                 the variator 
               
               
                 Y_MDYN 
                 set gradient portion of the actuating variable of 
               
               
                   
                 the variator 
               
               
                 Y_GES 
                 actuating variable for variator 
               
               
                 Y_RG 
                 output value of regulator 
               
               
                 MMOT 
                 motor torque 
               
               
                 MDYN_MOT 
                 dynamic motor torque 
               
               
                 M-CVT 
                 non-interactive torque of the variator regulation 
               
               
                 DKI 
                 throttle flap data = load position 
               
               
                 dnLS_SW 
                 set value-offset 
               
               
                 Theta_MOT 
                 motor inertial torque 
               
               
                 i-CVT 
                 actual variator ratio 
               
               
                 il, i2 
                 stage of ratio 
               
               
                 KF(i) 
                 characteristic field 
               
               
                 v 
                 velocity (speed) of vehicle 
               
               
                 GW 
                 threshold vehicle speed