DE102014224946B4 - Belting for a motor vehicle - Google Patents

Abstract

A belt transmission (1) for a motor vehicle (2), comprising at least the following components:
A first conical disk pair (3) on a first transmission shaft (4), the first conical disk pair (3) comprising a first control disk (5) and a first counter disk (6), the first control disk (5) being axially movable;
A second conical disk pair (7) on a second transmission shaft (8), the second conical disk pair (7) comprising a second control disk (9) and a second counter disk (10), the second control disk (9) being axially movable; and
A belting means (11), via which the first conical disk pair (3) and the second conical disk pair (7) can be connected in a torque-transmitting manner,
characterized in that
at least the first counter-disc (6) is axially movable from a zero operating position to a translation operating position to reduce a track offset (12) of the belt (11).

Description

The invention relates to a belt transmission for a motor vehicle, a method for reducing a track offset when changing a translation on a belt transmission, in particular for a belt transmission of a motor vehicle.

From the state of the art are known Umschlingungsgetriebe with which (at least partially) a stepless change in the translation (or reduction) is possible. These are therefore assigned to the group of continuously variable transmission, the CVT (Continuously Variable Transmission), or partly because of the dominance in the automotive sector under the CVTs alternatively referred to as CVT. The invention relates to Umschlingungsgetriebe, which have two conical disk pairs. Each pair of conical disks comprises two conical disks each. The conical disks are each aligned with their conical surface towards each other and displaceable relative to each other along their common axis of rotation, wherein a conical disk, the counter pulley, is axially fixed and the other conical disk, the control disk, is axially displaceable. About a common belt, for example, a transmission chain, the two conical disk pairs are connected to each other to transmit torque. The wrapping means migrates radially outwardly as the conical discs of a cone pulley pair are fed toward each other and radially inwardly as the conical disc pairs move away from each other. The cone pulley pairs are each moved in opposite directions, so that the circulation length for the belt means (almost) remains constant and thus the Umschlingungsmittelspannung (almost) kept constant. As a rule, therefore, the sum of the distances between the first conical disk pair and the second conical disk pair is (almost) constant.

Relative to a first pair of conical disks, a first transmission shaft, for example the transmission input shaft, is rotationally fixed and a second transmission shaft, for example a transmission output shaft, is rotationally fixed relative to a second pair of conical disks connected in a torque-transmitting manner by means of the belt. Depending on the selected distance of the conical disks relative to each other in relation to the selected distance of the other cone pulley pair, a ratio between the transmission shafts is adjustable. Such a belt transmission is for example from the DE 100 17 005 A1 known. In some applications, the belt transmission is combined with a conventional gearbox with fixed gear ratios, so that a larger transmission spread is achieved with a relatively smaller number of fixed gear ratios.

From the DE 197 01 859 A1 is another continuous transmission with a flexible belt means known, wherein the belt is guided over two pairs of cone pulley pairs whose relative distance determines the transmission ratio. A conical disk of one pair can be moved axially to the other conical disk to vary the position of the belt and thus the transmission ratio. The cone pulley is moved mechanically by means of a servo-driven lever or a servo screw drive. The thrust lever is driven by a hydraulic actuating cylinder. A screw drive has rotating servomotors, z. B. small electric motors with regulated end positions.

As a result of the always opposite changes in the distance between the two cone pairs in order to keep the chain tension constant, a so-called track offset occurs. That is, the center of the loop of the belt means is not located on a (common) wrapper plane which is (ideally) oriented perpendicular to the axes of rotation of the pulley pairs and gear shafts. This means that during one revolution the wrapping means (multiply) executes a deflection movement, which is aligned transversely to the running direction or transversely to the shortest connecting line, namely the distance, between the axes of rotation of the conical disk pairs. This movement leads to noise emissions as well as wear on the belt and the surfaces of the conical disks.

In order to minimize the track offset, it is customary to arrange the control disk of the cone pairs each mirrored. In this way, it is achieved that the maximum track offset is reduced in terms of amount (almost) by half in which a portion of the track offset is shifted into a negative range. This is on 1 and the related description. From the DE 102 09 513 A1 For this purpose, a geometric arrangement is known in which the track offset fluctuates around zero, so that from a new state to a (worn) old state, the center of the track offset as little as possible from zero.

A wrap-around gear can be characterized by the distance between parallel tangents of the counter disks or by the distance parallel to the axes of rotation at the average transmission diameter of the two conical disk pairs. These distances are optimized according to the prior art. This is for example in the JP 2011/112 112 A and the JP 2005/214 238 A shown. In the previously known solutions, however, the track offset is only minimized and not completely compensated.

In order to reduce the track offset at high load and high rotational speed in a continuously variable belt transmission is in the JP 2013-007 397 A proposed an adjustment mechanism for reducing the track offset, in which the output shaft is displaced as a whole.

On this basis, the present invention has the object of at least partially overcome the disadvantages known from the prior art. The object is solved with the features of the independent claims 1, 5 and 8. Advantageous embodiments are shown in the dependent claims. The features of the claims may be combined in any technically meaningful manner, and to this end, the explanations of the following description and features of the figures may be used, which include additional embodiments of the invention.

• – ein erstes Kegelscheibenpaar auf einer ersten Getriebewelle, wobei das erste Kegelscheibenpaar eine erste Steuerscheibe und eine erste Gegenscheibe umfasst, wobei die erste Steuerscheibe axial bewegbar ist;
• – ein zweites Kegelscheibenpaar auf einer zweiten Getriebewelle, wobei das zweite Kegelscheibenpaar eine zweite Steuerscheibe und eine zweite Gegenscheibe umfasst, wobei die zweite Steuerscheibe axial bewegbar ist; und
• – ein Umschlingungsmittel, über welches das erste Kegelscheibenpaar und das zweite Kegelscheibenpaar drehmomentübertragend verbindbar sind. Das Umschlingungsmittelgetriebe ist vor allem dadurch gekennzeichnet, dass zumindest die erste Gegenscheibe aus einer Null-Betriebslage heraus hin zu einer Übersetzungsbetriebslage axial bewegbar ist, um einen Spurversatz des Umschlingungsmittels zu reduzieren.

The invention relates to a belt transmission for a motor vehicle, wherein the belt transmission comprises at least the following components:

• A first conical disk pair on a first transmission shaft, wherein the first conical disk pair comprises a first control disk and a first counter disk, wherein the first control disk is axially movable;
• A second conical disk pair on a second transmission shaft, wherein the second conical disk pair comprises a second control disk and a second counter disk, wherein the second control disk is axially movable; and
• - An Umschlingungsmittel, via which the first cone pulley pair and the second cone pulley pair are connected to transmit torque. The belt transmission is primarily characterized in that at least the first counter-pulley is axially movable out of a zero operating position towards a Übersetzungsbetriebslage to reduce a track offset of the belt.

The belt drive claimed here is substantially set up such that the functions of known belt transmissions can be fulfilled as described above and are known from, for example, the prior art included. For this purpose, the first and second cone pulley pair are provided, in each of which a control disk is provided, by means of which the translation is variable, the chain tension (almost) is kept constant. Particularly preferably, the conventional construction is adopted, in which the control disks are each mirrored with respect to each other with respect to a Umschlingungsmittelebene arranged, which is not absolutely necessary in the present belt transmission. The axes of rotation of the cone pulley pairs are normally aligned on the belt center plane. This can cause minor technical deviations within the framework of the respectively selected manufacturing accuracy as well as due to dynamic material properties under load.

The wrapping means proposed here is preferably clamped by means of frictional connection between the respective conical disks of the cone pulley pairs, so that, for example, in a belt in embodiment with tabs and bolts, the driving force is transmitted frictionally or non-positively in Bolzenachsrichtung on the bolts of the belt. Such a configuration is particularly suitable for use in a motor vehicle, in the usual rotational speeds between 800 rev / min [revolutions per minute] to 8,000 rev / min and at the same time torques in the range of 50 Nm [Newton meters] to 1,000 Nm are to be transmitted. For other purposes and applications, other wrappers may be used.

In the case of the belt-type transmission proposed here, in contrast to the prior art, the first counter-disk is not axially fixed. On the contrary, the first counter-disc is out of a zero operating position, which is preferably formed by a stop, adapted to the state of translation of the cone pulley pairs axially displaceable, wherein the new (respectively adapted) position is referred to as Übersetzungsbetriebslage. In this case, the transmission operating position is preferably set up in such a way that the belt mean plane is always aligned perpendicular to the transmission shafts. For many applications, however, it is sufficient not to completely compensate for the track offset, but merely to reduce it, for example to 80% [percent], preferably 50%, particularly preferably 20% of a conventional track offset based on the design of the belt drive. In such, possibly economically optimal, embodiment for reducing the track offset angle, for example, the ideal Umschlingungsmittelebene, which is aligned perpendicular to the transmission shafts, of less than 10 arc seconds, preferably less than 5 arc seconds reached. If a complete compensation of the track offset can be achieved, it is preferred to achieve a track offset compensation which deviates from the ideal in terms of the control technology. In such an intermediate state, the angle of the belt mean plane to the ideal plane perpendicular to the transmission shafts is preferably below 10 Angular seconds, preferably less than 5 angular seconds.

The length of the axial distance, on which the first counter-disk is movable, corresponds to at least 20%, preferably 50%, particularly preferably 80% of the occurring track offset or even the total occurring track offset, particularly preferably plus an axial clearance to execute this compensation, for example, without impact to be able to or at least to ensure that a compensation in the specified extent at specified manufacturing tolerance is executable.

The zero operating position is an axial position of the first counter-disc, in which, based on the design of the cone pulley pair or the entire belt transmission no track offset compensation must take place, such as in 1 shown. The zero operating position is, for example, a position on a stop. It can also be in or near, that is, left or right, the center of the axial compensation path, but also arbitrary selectable. Starting from the invention, the zero operating position is therefore a special translation operating position, in which no tracking offset occurs even with an axially fixed counter-disk of the prior art.

• – zumindest ein axiales Hydrauliksystem;
• – zumindest ein Schneckentrieb; und
• – zumindest ein elektro-mechanischer Lineartrieb.

In a further advantageous embodiment of the belt drive, at least one of the following drive means is provided for moving the first counter-pulley:

• - at least one axial hydraulic system;
• - at least one worm drive; and
• - At least one electro-mechanical linear actuator.

Particularly preferably, an axial hydraulic system is used for the axial movability of the first counter-disk. This is particularly economical because in many applications for the axial mobility of the control discs also an axial hydraulic system is used. In a particularly preferred embodiment, therefore, no additional (hydraulic) units are needed. Preferably, the first mating disk is the same or similar to the associated control disk. Particularly preferably, the first mating disk is already at a distance from a possible stop in the zero operating position, so that the first mating disk is fully functional even in this state, because the necessary actuating pressure is built up, and also no adhesion effects or squeeze film Effects occur. An additional advantage is that an additional force measurement is not necessary, with which it is ensured that the force on the belt is sufficiently large and not too large. On the contrary, the axial force is preferably adjustable to the Umschlingungsmittelgetriebe means of the balance of power on the control of the control disc. The ratio of forces is preferably set geometrically (ratio of the axially acting hydraulic surfaces (piston surfaces) of the antagonist control disc and counter-disc).

In another advantageous embodiment, the first counter-disk is moved axially by means of a worm drive. It is particularly advantageous that a worm gear is self-locking buildable, so that no forces must be applied when the first mating disk has been transferred to a corresponding position (Übersetzungsbetriebslage).

In a further advantageous embodiment, an electromechanical linear drive is provided, in which the first counter-disc with magnetic effect, preferably in interaction with a spring bias, is movable. This can also be combined with discrete detent positions so that the forces in such positions are (almost) balanced. Such a construction is space-saving and simple and also quickly adjustable.

In addition, it is also possible to use a combination of the drive means, wherein preferably a drive means is arranged for holding a translation position.

In a further advantageous embodiment of the belt-type transmission, the first counter-disk is axially movable by means of a first hydraulic system, the first hydraulic system having a first piston surface, and wherein the first control disk is axially movable by means of a second hydraulic system, the second hydraulic system having a second piston surface the first piston surface is larger than the second piston surface, wherein preferably the first hydraulic system can be supplied by means of a separate pressure transducer.

The piston surfaces are the axially acting hydraulic surfaces, by means of which, multiplied by the applied pressure, the respective axial force for moving the control disk (second piston surface) or the counter-disk (first piston surface) can be generated. In a preferred embodiment, the first hydraulic system and the second hydraulic system are supplied via a common line and / or via a common pump. Particularly preferred two completely separate hydraulic systems are provided, in which both the lines and the pumps are separated from each other. As a result, deviations from the track offset compensation can be compensated quickly and easily.

In this embodiment, the first piston surface of the first counter-disc is larger than the second piston surface of the first control disc, which is prevented at pressures of the same magnitude that the force on the counter-disc is smaller than the force on the control disc, so that a change in the translation no Can cause track offset. Most preferably, the second piston surface is at most half as large as the first piston surface, most preferably less than a quarter of the first piston surface.

• – Verändern eines ersten Abstands zwischen dem ersten Kegelscheibenpaar;
• – Verändern eines zweiten Abstands zwischen dem zweiten Kegelscheibenpaar um den Betrag der Änderung des ersten Abstands in entgegengesetzter Richtung zum Verändern des ersten Abstands, sodass die Summe aus dem Betrag des ersten Abstands und dem Betrag des zweiten Abstands konstant bleibt. Das Verfahren kennzeichnet sich dabei vor allem dadurch, dass weiterhin die axiale Betriebslage der ersten Gegenscheibe derart verändert wird, dass das Umschlingungsmittel stets in einer Laufebene angeordnet ist, zu welcher die erste Getriebewelle und die zweite Getriebewelle senkrecht angeordnet sind.

According to a further aspect of the invention, a method for reducing a track offset when changing a gear ratio on a belt transmission according to an embodiment of the above description is proposed, which comprises at least the following steps:

• - changing a first distance between the first cone pulley pair;
• Changing a second distance between the second conical disk pair by the amount of change of the first distance in the opposite direction to changing the first distance, so that the sum of the first distance amount and the second distance amount remains constant. The method is characterized in particular by the fact that further the axial operating position of the first counter-disc is changed such that the belt is always arranged in a running plane to which the first gear shaft and the second gear shaft are arranged vertically.

According to this method, the operating position of the first counter-disc is always adapted to the translation, so that the track offset is (almost) zero. The method is in this case carried out with a control system, which naturally has a (small) time offset, so that in an intermediate position with a change in the translation and rapid translation changes, the compensation of the operating position of the first mating pulley remains behind an optimal balance. After a (short) latency, preferably in the millisecond range, and at a fixed ratio on the belt transmission, however, the running plane is preferably set very accurately, so that then the deviation from a respective (intermediate) target position is less than 5 arc seconds. For some applications, however, deviations of up to 10 arc seconds, for example for economic reasons, are sufficient. However, at no time is a deviation of 10 arcseconds, preferably 5 arcseconds, exceeded at any time.

In a further advantageous embodiment of the method, the position of the first mating pulley is hydraulically regulated, wherein preferably a compensating force is applied counter to the switching force of the first control disk aligned, wherein the compensating force is always greater than the switching force.

In this embodiment of the method, a belt transmission with a first piston surface is preferably used on the first counter-disk and a second piston surface on the first control disk, by means of which the positions are hydraulically adjustable. By this measure, it is possible to ensure that the balancing force is always greater than the switching force on the first control disk. However, configurations are also possible in which the compensating force is determined or the travel of the control disk and / or the counter-disk so that safe operation is possible, wherein at the same time a quick compensation can be carried out at a track offset.

According to a further aspect of the invention, a drive train is proposed, which has a drive unit with an output shaft and a belt transmission in an embodiment according to the above description, wherein the output shaft for torque transmission by means of the variable-speed transmission with at least one consumer is connectable.

The drive train is set up to transmit a torque supplied by a drive unit, for example an energy conversion machine, preferably an internal combustion engine or an electric motor, and output via its output shaft to at least one variable-speed and / or variable torque consumer. An exemplary consumer is at least one drive wheel of a motor vehicle and / or an electric generator for the provision of electrical energy. Conversely, a recording of an inertial energy introduced, for example, by a drive wheel (for example in coasting mode) can also be implemented. The at least one drive wheel then forms the drive unit, wherein preferably its inertial energy can be transmitted by means of the belt drive to an electric generator for recuperation, ie for the electrical storage of the braking energy, with a suitably configured drive train. Furthermore, in a preferred embodiment, a plurality of drive units are provided, which can be loaded as required by means of the belt drive, that is, such an adjustable proportion of applied torque is available for use. An example is a hybrid drive of electric motor and internal combustion engine for, for example, a motor vehicle. The wrap-around gear proposed here is particularly low-wear and low-noise. It also follows that there is an increased Life has. The belt transmission is operable by means of the method described above.

According to a further aspect of the invention, a motor vehicle is proposed, which has at least one drive wheel which can be driven by means of a drive train according to the above description.

Most motor vehicles today have a front-wheel drive and therefore preferably arrange the drive unit, for example an internal combustion engine or an electric motor, in front of the driver's cab and transversely to the main drive direction. The space is particularly small in such an arrangement and it is therefore particularly advantageous to use a belt drive small size. This means that wrapping means, preferably with chain links, should be used as small as possible. The belt transmission proposed here has a reduced (transverse) load on the belt and can therefore be executed with the same load and at least the same service life with a significantly smaller belt.

This problem is exacerbated in passenger cars of the small car class according to European classification. The units used in a passenger car of the small car class are not significantly reduced compared to passenger cars larger car classes. Nevertheless, the available space for small cars is much smaller.

Passenger cars are assigned to a vehicle class according to, for example, size, price, weight and power, and this definition is subject to constant change according to the needs of the market. In the US market, cars of the class small cars and microcars are classified according to European classification of the class of Subcompact Car and in the British market they correspond to the class Supermini or the class City Car. Examples of the micro car class are a Volkswagen up! or a Renault Twingo. Examples of the small car class are an Alfa Romeo Mito, Volkswagen Polo, Ford Fiesta or Renault Clio.

The above-described invention will be explained in detail in the background of the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is not limited by the purely schematic drawings in any way, it being noted that the drawings are not dimensionally accurate and are not suitable for the definition of size ratios. It is shown in

1 : a plot of the track offset over the translation;

2 : a belt drive with compensating counter-disc with common pressure supply;

3 : the geometric context for the characterization of a belt drive;

4 : a belt drive with separate pressurization;

5 : a first pair of conical disks with worm drive;

6 : a first pair of conical disks with electro-mechanical linear drive; and

7 : a powertrain in a motor vehicle.

In 1 is a diagram with a track offset axis 48 in millimeters and a gear ratio abscissa 47 with a gear ratio range between 2.4 and 0.4 an exemplary relationship between set gear ratio and resulting track offset 12 shown as a curve. The maximum track offset 12 is above 0.45 mm [millimeters] and the minimum track offset 12 at below -0.2 mm. At a gear ratio between 2.1 and 2.0 or at about 0.5, the track offset 12 zero. These points correspond in the present invention to a (assumed) otherwise same configuration of the belt drive the zero operating position. In the present invention, a track offset 12 of (near) zero. This is shown in the following figures.

In 2 is a belt drive 1 with a first cone pulley pair 3 and a second cone pulley pair 7 shown here, wherein here the belt 11 (see 4 ) is not shown. The first cone pulley pair 3 consists of a first control disc 5 and a first counter-disc 6 on a first gear shaft 4 together. The second cone pulley pair 7 is made up of a second control disc 9 and a second mating disk 10 on a second gear shaft 8th together. Here, the first transmission shaft is preferred 4 with a drive unit 24 (see 5 ) and the second transmission shaft 8th with the downforce. In this embodiment, the first piston surface 16 the first counter-disc 6 and the second piston surface 18 the first control disc 5 almost identical. For compression of the Information content is the first tax disc 5 and the second control disc 9 each shown in the minimum position and in the maximum position. This includes the positions of the control discs 5 and 9 each outside the transmission shafts 4 and 8th or respectively between the transmission shafts 4 and 8th together. In this example, the second mating disk is 10 fixed, but in principle can also be moved like the first counter-disc 6 be furnished. The first gear shaft 4 and the second transmission shaft 8th are with a center distance 31 spaced apart and have defined a transmission characteristic based on the track offset 12 on. In one approach, the parallel distance becomes 35 the opposite discs, here the first counter-disc 6 and the second mating disk 10 , with a disc tilt angle 34 sized. Preference is given to a mean effective diameter 32 respectively 33 each half distance 36 to the walking level 22 established. This geometric relationship is shown in the schematic overview in 3 detailed again.

In 3 a schematic representation of the characterizing geometric relationship of a belt transmission is shown, wherein the upper line and the lower line, the first transmission shaft 4 and the second transmission shaft 8th represent, which by the center distance 31 spaced apart from each other. The parallel distance 35 this results from the shortest distance to the parallel disc tangents under the disc inclination angle 34 , The distance 46 at the mean effective diameter 32 respectively 33 (see 2 ), ie the sum of the half-distances 36 (see 2 ) at the mean effective diameter 32 and 33 , is between the first mean effective radius 44 and the second mean effective radius 45 Are defined. The parallel distance 35 [B _L ] and the distance at the mean effective diameter 46 [B ₀ ] are by means of the disc inclination angle 34 [φ], the magnitude of the same mean effective radii 44 and 45 [r _M ] and the center distance 31 [a] linked together by the following mathematical relationship: B _L = (a - 2r _M ) sin φ + B ₀ cosφ respectively

In 4 is another configuration of a belt drive 1 shown in which a belt 11 in a neutral transmission position (central operating position), lowest transmission position or largest reduction position (on the first conical disk pair 3 and on the second cone pulley pair 7 the highest operating position) and highest translation position (on the first cone pulley pair 3 and on the second cone pulley pair 7 the lowest operating position) starting from the first gear shaft 4 is shown. That's a first distance 38 or a second distance 39 at highest translation and a first distance 40 or a second distance 41 at the lowest translation and again a first distance 20 or a second distance 21 associated with neutral translation. Here is the location of these distances 20 . 21 . 38 . 39 and 40 . 41 by means of the first counter-disc 6 which is axially movable, each set so that no track offset 12 occurs and therefore the transmission shafts 4 and 8th to the run levels 22 always aligned normally. Here, this is due to the first hydraulic system 13 with the balancing pressure 43 on the first piston surface 16 reached, which is the control pressure 42 on the second piston surface 18 counteracts. On the second piston surface 18 acts a second axial hydraulic system 17 one. This will be the walking level 22 offset exactly parallel. In this embodiment, the first axial hydraulic system 13 from a separate pressure transmitter 19 , for example a pump, which supplies a hydraulic fluid from a hydraulic reservoir 37 as required.

5 shows isolated a first conical disk pair 3 as it is for example in 4 is shown. Here is the first counter-disc 6 by means of a worm gear shown purely schematically 14 translatable into a required translation operation.

6 shows isolated a first conical disk pair 3 as it is for example in 4 is shown. Here is the first counter-disc 6 by means of a purely schematically illustrated electro-mechanical linear actuator 15 translatable into a required translation operation.

In 7 is a powertrain 23 comprising a drive unit 24 , shown here as an internal combustion engine, an output shaft 25 , a belt drive 1 and a torque transmitting connected left drive wheel 26 and right drive wheel 27 , shown schematically. The powertrain 23 is here in a motor vehicle 2 arranged, wherein the drive unit 24 with its motor axis 30 transverse to the longitudinal axis 29 in front of the driver's cab 28 is arranged.

With the belt transmission proposed here, the efficiency and the longevity is improved and at the same time the contact stability is increased. In addition, the running conditions are improved and the noise emission is reduced.

LIST OF REFERENCE NUMBERS

1

wrap-around

2

motor vehicle

3

first conical disk pair

4

first gear shaft

5

first control disk

6

first counter-disc

7

second cone pulley pair

8th

second transmission shaft

9

second control disk

10

second mating disk

11

endless

12

offtrack

13

first axial hydraulic system

14

worm drive

15

electro-mechanical linear actuator

16

first piston surface

17

second axial hydraulic system

18

second piston surface

19

separate pressure transmitter

20

first distance with neutral translation

21

second distance with neutral translation

22

running plane

23

powertrain

24

drive unit

25

output shaft

26

left drive wheel

27

right drive wheel

28

cab

29

longitudinal axis

30

motor axis

31

Wheelbase

32

first average effective diameter

33

second average effective diameter

34

Plate inclination angle

35

parallel distance

36

Half distance at the mean effective diameter

37

hydraulic reservoir

38

first distance with highest translation

39

second distance at highest translation

40

first distance with lowest translation

41

second distance with lowest translation

42

control pressure

43

balancing pressure

44

first average effective radius

45

second average effective radius

46

Distance at the mean effective diameter

47

Gear ratio abscissa

48

Off-track axis

Claims (8)

Belt transmission ( 1 ) for a motor vehicle ( 2 ), comprising at least the following components: - a first conical disk pair ( 3 ) on a first transmission shaft ( 4 ), wherein the first cone pulley pair ( 3 ) a first control disk ( 5 ) and a first counter-disk ( 6 ), wherein the first control disk ( 5 ) is axially movable; A second conical disk pair ( 7 ) on a second gear shaft ( 8th ), wherein the second cone pulley pair ( 7 ) a second control disk ( 9 ) and a second counter-disk ( 10 ), wherein the second control disk ( 9 ) is axially movable; and - a wrapping means ( 11 ), over which the first conical disk pair ( 3 ) and the second cone pulley pair ( 7 ) are torque-transmitting connectable, characterized in that at least the first counter-disc ( 6 ) is axially movable from a zero operating position to a translation operating position to a track offset ( 12 ) of the belt ( 11 ) to reduce. Belt transmission ( 1 ) according to claim 1, wherein at least one of the following driving means for moving the first counter-disc ( 6 ) is provided: - at least one axial hydraulic system ( 13 ); At least one worm drive ( 14 ); and at least one electro-mechanical linear drive ( 15 ). Belt transmission ( 1 ) according to claim 1 or 2, wherein the first counter-disc ( 6 ) by means of a first hydraulic system ( 13 ) is axially movable, wherein the first hydraulic system ( 13 ) a first piston surface ( 16 ), and wherein the first control disk ( 5 ) by means of a second hydraulic system ( 17 ) is axially movable, wherein the second hydraulic system ( 17 ) a second piston surface ( 18 ), wherein the first piston surface ( 16 ) larger than the second piston surface ( 18 ). Belt transmission ( 1 ) according to claim 3, characterized in that the first hydraulic system ( 13 ) by means of a separate pressure transducer ( 19 ) is available. Method for reducing a track offset ( 12 ) when changing a translation on a belt transmission ( 1 ) according to one of the preceding claims, comprising at least the following steps: - changing a first distance ( 20 ) between the first conical disk pair ( 3 ); Changing a second distance ( 21 ) between the second cone pulley pair ( 7 ) in the opposite direction to changing the first distance ( 20 ) and the amount of change in the first distance ( 20 ), so that the sum of the amount of the first distance ( 20 ) and the amount of the second distance ( 21 ) remains constant; characterized in that further the axial operating position of the first counter-disc ( 6 ) is changed such that the wrapping means ( 11 ) always in one level ( 22 ) is arranged, to which the first transmission shaft ( 4 ) and the second transmission shaft ( 8th ) are arranged vertically. Method according to claim 5, wherein the position of the first counter-disc ( 6 ) is hydraulically regulated, wherein a compensating force against the switching force of the first control disk ( 5 ) is applied aligned, wherein the balancing force is always greater than the switching force. Powertrain ( 23 ), comprising a drive unit ( 24 ) with an output shaft ( 25 ) and a belt transmission ( 1 ) according to one of claims 1 to 3, wherein the output shaft ( 25 ) for torque transmission by means of the belt drive ( 1 ) with a variable translation with at least one consumer ( 26 . 27 ) is connectable. Motor vehicle ( 2 ) comprising at least one drive wheel ( 26 . 27 ), which by means of a drive train ( 23 ) is drivable according to claim 7.

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