Abstract: A method is provided for heating components of a vehicle having a first electric drive unit, a second electric drive unit, and an inverter system for supplying the electric drive units with alternating current. The first electric drive unit produces a first torque and the second electric drive unit produces a second torque, where a sum of the first and second torques is a driving torque. For producing a desired driving torque the first electric drive unit is operated as a generator and the second electric drive unit is operated as a motor so that a total current flow is produced in the inverter system that is greater than a total current flow that would be produced in the inverter system when both electric drive units are operated as motors to produce the desired driving torque.

Abstract: A method for ensuring a desired shifting state in a shiftable electric drivetrain (16) of a vehicle (15) is characterized in that the method includes an ascertaining process during which it is ensured that the desired shifting state corresponds to an actual shifting state.

Abstract: A method for operating a motor vehicle (1) having at least one driven axle (3) with a locking differential (10a), where when the motor vehicle (1) is driving and the locking differential (10a) concerned is engaged on at least one driven axle (3), it is checked whether the motor vehicle is driving round a curve. If it is found that the motor vehicle is driving round a curve, the engaged locking differential (10a) is actuated to disengage it and it is checked whether the locking differential (10a) concerned has in fact been disengaged. If it is found that the locking differential (10a) concerned has not been disengaged, the wheel of the driven axle (3) concerned on the outside of the curve is braked.

Abstract: The present invention relates to a method for resolving a tooth-on-tooth position of a positive-locking shifting element of an automated manual transmission, in which gear steps of the automated manual transmission are changed by means of a pressure-medium-actuated shift actuator. If, during a change of a gear step of the automated manual transmission, a tooth-on-tooth position occurs at the interlocking shifting element, then the control of the pressure-medium-actuated shift actuator is varied in such manner as to resolve the tooth-on-tooth position. A control unit for carrying out the method is also disclosed.

Abstract: A method for operating a motor vehicle drive train having a drive aggregate, an automated group transmission connected between the drive aggregate and a drive output, and a disconnect clutch connected between the drive aggregate and the group transmission. The group transmission has a plurality of sub-transmissions, including a main transmission, a splitter group upstream from the main transmission, and a range group downstream from the main transmission. When the disconnect clutch cannot be shifted to carry out a shifting operation in the group transmission, an emergency shifting program is activated. Shifting from a current gear to a target gear is carried out automatically, as a function of input rotation speed of the group transmission or as a function of rotation speed of the drive aggregate, while the disconnect clutch is closed and where the main transmission and/or the range group participate exclusively, but not the splitter group.

Abstract: A method for operating a motor vehicle (1) having at least one driven axle (3) with a locking differential (10a), where when the motor vehicle (1) is driving and the locking differential (10a) concerned is engaged on at least one driven axle (3), it is checked whether the motor vehicle is driving round a curve. If it is found that the motor vehicle is driving round a curve, the engaged locking differential (10a) is actuated to disengage it and it is checked whether the locking differential (10a) concerned has in fact been disengaged. If it is found that the locking differential (10a) concerned has not been disengaged, the wheel of the driven axle (3) concerned on the outside of the curve is braked.

Abstract: A method for operating a drive train of a motor vehicle, where the drive train includes a drive aggregate, a group transmission connected between the drive aggregate and a drive output, and a separating cutch connected between the drive aggregate and the group transmission. If a speed is lower than a limit value, the separating clutch is opened and for transmission preselection one or all the other sub-transmission(s) is/are changed to a friction-force-locking condition. The separating clutch is then at least partially closed and the drive aggregate is brought to a defined rotation speed. When a friction-force-locking group transmission is required, it is checked whether a starting gearshift or a driver-desired shift for the group transmission is called for and the target rotation speed of the drive aggregate is checked. Depending on the results, the sub-transmission can be synchronized by a transmission brake or by the drive aggregate.

Abstract: A method for operating a motor vehicle drive train having a drive aggregate, an automated group transmission connected between the drive aggregate and a drive output, and a disconnect clutch connected between the drive aggregate and the group transmission. The group transmission has a plurality of sub-transmissions, including a main transmission, a splitter group upstream from the main transmission, and a range group downstream from the main transmission. When the disconnect clutch cannot be shifted to carry out a shifting operation in the group transmission, an emergency shifting program is activated. Shifting from a current gear to a target gear is carried out automatically, as a function of input rotation speed of the group transmission or as a function of rotation speed of the drive aggregate, while the disconnect clutch is closed and where the main transmission and/or the range group participate exclusively, but not the splitter group.

Abstract: A method for operating a drive train of a motor vehicle, where the drive train includes a drive aggregate, a group transmission connected between the drive aggregate and a drive output, and a separating cutch connected between the drive aggregate and the group transmission. If a speed is lower than a limit value, the separating clutch is opened and for transmission preselection one or all the other sub-transmission(s) is/are changed to a friction-force-locking condition. The separating clutch is then at least partially closed and the drive aggregate is brought to a defined rotation speed. When a friction-force-locking group transmission is required, it is checked whether a starting gearshift or a driver-desired shift for the group transmission is called for and the target rotation speed of the drive aggregate is checked. Depending on the results, the sub-transmission can be synchronized by a transmission brake or by the drive aggregate.

Abstract: The present invention relates to a method for resolving a tooth-on-tooth position of a positive-locking shifting element of an automated manual transmission, in which gear steps of the automated manual transmission are changed by means of a pressure-medium-actuated shift actuator. If, during a change of a gear step of the automated manual transmission, a tooth-on-tooth position occurs at the interlocking shifting element, then the control of the pressure-medium-actuated shift actuator is varied in such manner as to resolve the tooth-on-tooth position. A control unit for carrying out the method is also disclosed.

Abstract: A method of operating a motor vehicle drive-train having a drive aggregate, a group transmission and a drive output. The aggregate can couple an input shaft of the transmission which includes main, splitter and range groups. To carry out a shift, a target gear and target rotational speed of the aggregate are calculated for the shift to be carried out. After the initiation of the shift a load reduction is first carried out, then a group of the transmission is disengaged in order to shift the transmission to neutral, after which a group of the transmission is synchronized and to shift out of neutral, the synchronized group is engaged, and then the load is again built up. Initiation of the shift, after calculating the target gear and the target rotational speed, occurs at a point in time when complete performance of a shift is not yet possible.

Abstract: A method of operating a motor vehicle drive-train having a drive aggregate, a group transmission and a drive output. The aggregate can couple an input shaft of the transmission which includes main, splitter and range groups. To carry out a shift, a target gear and target rotational speed of the aggregate are calculated for the shift to be carried out. After the initiation of the shift a load reduction is first carried out, then a group of the transmission is disengaged in order to shift the transmission to neutral, after which a group of the transmission is synchronized and to shift out of neutral, the synchronized group is engaged, and then the load is again built up. Initiation of the shift, after calculating the target gear and the target rotational speed, occurs at a point in time when complete performance of a shift is not yet possible.

Abstract: A method of controlling the gear shifting of an automatic range-change transmission, which is arranged between a drive engine and a final drive in a drive train of a motor vehicle and includes at least one multi-stage main transmission, a two-stage front-mounted group upstream of the main transmission, and a transmission brake. The main transmission can be shifted, via unsynchronized clutches, and the front-mounted group can be shifted, via synchronized clutches. Upon upshifting in the range-change transmission including at least one change of a transmission ratio stage of the front-mounted group, synchronization of the front-mounted group is effected via actuation of the synchronized clutch of the front-mounted group and supportingly via at least intermittently parallel actuation of the transmission brake. Actuation of the transmission brake, for supporting the synchronization of the front-mounted group, is effected on the basis of a prevailing driving or operating situation.

Abstract: A method for shift control of an automated auxiliary transmission that is mounted in a drive train of a motor vehicle between a drive motor (AM) and a final drive, and includes at least one multi-step main gearing (HG) and one two-step front-mounted group (VG) connected upstream of the main gearing (HG), and with which the main gearing (HG) can be shifted via unsynchronized clutches and the front-mounted group can be shifted via synchronized clutches. Depending on the currently existing driving or operating situation, a gear change is performed in the auxiliary transmission through a change in the transmission ratio step (G1, G2, G3) of the main gearing (HG) while maintaining the currently engaged transmission ratio step (K1, K2) in the front-mounted group (VG).

Abstract: A method of controlling the gear shifting of an automatic range-change transmission, which is arranged between a drive engine and a final drive in a drive train of a motor vehicle and includes at least one mufti-stage main transmission, a two-stage front-mounted group upstream of the main transmission, and a transmission brake. The main transmission can be shifted, via unsynchronized clutches, and the front-mounted group can be shifted, via synchronized clutches. Upon upshifting in the range-change transmission including at least one change of a transmission ratio stage of the front-mounted group, synchronization of the front-mounted group is effected via actuation of the synchronized clutch of the front-mounted group and supportingly via at least intermittently parallel actuation of the transmission brake. Actuation of the transmission brake, for supporting the synchronization of the front-mounted group, is effected on the basis of a prevailing driving or operating situation.

Abstract: A method for shift control of an automated auxiliary transmission that is mounted in a drive train of a motor vehicle between a drive motor (AM) and a final drive, and includes at least one multi-step main gearing (HG) and one two-step front-mounted group (VG) connected upstream of the main gearing (HG), and with which the main gearing (HG) can be shifted via unsynchronized clutches and the front-mounted group can be shifted via synchronized clutches. Depending on the currently existing driving or operating situation, a gear change is performed in the auxiliary transmission through a change in the transmission ratio step (G1, G2, G3) of the main gearing (HG) while maintaining the currently engaged transmission ratio step (K1, K2) in the front-mounted group (VG).

Abstract: A method of controlling an automated transmission with positioning cylinders (6, 8, 20) controlled by shift valves or venting valves (10, 12, 16, 18, 22, 24). At least one cut-off valve (4) is positioned in front of the shift or venting valves and a control device controls the valves while pressure pipes, which follow the cut-off valve (4), are connected with one another following the cut-off valve (4). Due to the fact that the cut-off valve (4), for reasons of design simplicity and cost, is generally designed as a simple 2/2 way valve which only allows pressure increase but not pressure reduction, the method provides control of the shift valves or ventilation or venting valves (16, 18), of a non activated positioning cylinder (8), so that the pressure pipe system is connected with an outflow pipe (14) for a pressure reduction in the pressure pipe system (30, 32, 34).

Abstract: A method of controlling and regulating a transmission brake which, for the purpose of synchronization, determines a target rotational speed of a shaft to be synchronized on the basis of an actual rotational speed of a transmission shaft, and controls a transmission brake such that the determined target rotational speed is set for the shaft that is to be synchronized. The transmission brake also carries out additional functions. These functions require no, or only minimal, additional hardware complexity in a cost-neutral way, but considerably increase the functional and practical value of the transmission brake. The comfort and speed of shifting operations, the protection or, as the case may be, the detection of error states in sensors, a clutch, a main clutch or a motor control are improved, and undesirable transmission states avoided. It is also possible to account for and influence other conditions, such as the operation of ancillary devices.

Abstract: A method of performing a shift operation in an automatic transmission with at least one form-locking shifting transmission part of a vehicle, with which, during a shift to a target gear (GZIEL), a rotational speed synchronization, between the transmission input rotational speed and the output side rotational speed, is performed. When a different rotational direction is detected between the transmission input and the transmission output, the rotational speed of the transmission input is reduced to a minimum and the target gear (GZIEL) is only shifted when the remaining rotational speed difference, between the rotational speed of the transmission input and the rotational speed of the transmission output can be at least substantially synchronized by the form-locking shift element.

Abstract: A method of eliminating a tooth-on-tooth position at an interlocking shifting element. The tooth-on-tooth position is eliminated by operating at least one actuator such that, during a first operating attempt the actuator is operated using a defined target parameter, after which it is checked whether as a result of the operation of the actuator the tooth-on-tooth position has been eliminated. If the tooth-on-tooth position is not eliminated, then repeating subsequent operating attempts of operation of the actuator, each time with an increased target parameter, until, after the corresponding operation of the actuator, the tooth-on-tooth position is eliminated by the m-th operating attempt. For elimination of a subsequent tooth-on-tooth position, the target parameter defined for the first elimination attempt is adapted such that the subsequent tooth-on-tooth position is eliminated by an n-th attempt.