WO2019120369A1

WO2019120369A1 - Belt-drive transmission for a drivetrain

Info

Publication number: WO2019120369A1
Application number: PCT/DE2018/100942
Authority: WO
Inventors: Bernhard Walter
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2017-12-20
Filing date: 2018-11-20
Publication date: 2019-06-27
Also published as: DE102018104379A1; DE112018006499A5

Abstract

The invention relates to a belt-drive transmission (1) for a drivetrain (2) comprising at least the following components: - a first and a second cone pulley pair (3, 4) each with an axis of rotation (5, 6) and each having a pulley diameter (7, 8), each comprising an axially fixed pulley (9, 10) and each comprising an axially displaceable free pulley (11, 12), wherein a radius of action (15) can be adjusted in each case; - a belt (17) for the variable ratio transmission of a torque between the first cone pulley pair (3) and the second cone pulley pair (4); - a first and a second axial actuator (18), by means of which the first or the second axial distance (13, 14) can be adjusted, wherein in each case an axial pulley/actuator distance (22, 23) from the respective fixed-pulley side surface (24, 25) of the respective maximum radius of action (52, 53) to the respective maximum axial end (26, 27) of the respective axial actuator (18, 19) is formed on the outer side (28, 29) facing away from the respective cone pulley pair (3, 4). The belt-drive transmission (1) is primarily characterized in that the ratio of the respective pulley diameter (7, 8) to the corresponding pulley/actuator distance (22, 23) on the two cone pulley pairs (3, 4) is greater than or equal to 1.75. The belt-drive transmission according to the invention has particularly small overall dimensions and is therefore particularly economical.

Description

Umschlinqunqsqetriebe for a Antriebsstranq

The invention relates to a belt drive for a drive train, comprising at least the following components:

a first and second cone pulley pair, each having a rotation axis and each having a disc diameter, each having an axially fixed

Fixed disk and each an axially displaceable loose disk, each one active circle is adjustable;

a wrapping means for translationally transmitting a torque between the first conical disk pair and the second

Conical pulley;

a first and second axial actuator, by means of which the first

or the second axial distance is adjustable, wherein in each case an axial disc-actuator distance from the respective disk-side surface of the respective maximum effective circle is formed to the respective maximum axial end of the respective Axialaktors on the outer side facing away from the respective conical disk pair.

The belt transmission is mainly characterized in that the ratio of the respective pulley diameter to the corresponding pulley-actuator distance is equal to or greater than 1.75 in both pulley pairs.

From the state of the art are Umschlingungsmittel-variators, as in continuously variable transmissions, as a belt drive or as CVT (Engl.

continuous variable transmission) is used. Such a variator has an input side cone pulley pair and an output side

Conical disk pair whose distance is adjustable in opposite directions, so that the running radii of a pressed between the cone pulley pairs

Umschlingungsmittels change and thus the translation is infinitely adjustable. The radii of rotation determine the respective active circle. The active circuit is, for example, at a center line of a circulation contact line with radial expansion, So a circulation contact surface, between belt and respective

Defined conical disk.

A pair of conical disks is shortened in the prior art also referred to as conical disks (plural) and a single conical disk of a conical disk pair as a conical disk half. For better clarity, often one of the

Cone pulley pairs as input disk set and the other cone pulley pair referred to as output disk set. This depends on the installation situation, wherein the input disk set with a drive machine, ie the drive,

torque transmitting connectable or connected and the

Output disk set with a consumer, ie the output,

torque transmitting connectable or connected. But because of the

Torque curve reversible for most applications, so in both

Directions is transferable, the functional context, unless explicitly pointed out to the contrary, is also valid vice versa. That is, the

Input disk set can be considered as output disk set and vice versa. By way of example, the variator can also be installed in the reverse direction, with expert adjustments possibly being made to peripheral components. A peripheral component is, for example, the actuator or a slide rail for damping the belt.

The pairs of conical disks each have a conical disk (fixed disk) fixedly connected to a shaft and a shaft that is non-rotatable but axially displaceable with the shaft

Cone disk (loose disk) on. The adjustment of the axial distance, or the displacement of the loose washers, can be done in different ways, for example by means of a respective electro-mechanical actuator or by means of a respective hydraulically actuated piston unit or cylinder unit. Both devices for moving the loose disks are referred to here as Axialaktor.

As a belt, for example, a push belt, a V-belt and a chain are known. There is a constant need to provide compactly constructed belt transmissions with an axially small installation space. This is necessary, for example, for a hybrid transmission and / or front-transverse internals, because in these cases the available installation space is particularly small due to the at least one additional electric machine compared to a pure combustion engine drive.

On this basis, the present invention has the object, at least partially overcome the known from the prior art disadvantages. The features of the invention will become apparent from the independent claims, to which advantageous embodiments are indicated 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 can be added, which comprise additional embodiments of the invention.

a first conical disk pair with a first axis of rotation and with a first disk diameter, comprising an axially fixed first fixed disk and an axially displaceable first floating disk, wherein a first active circle is adjustable by means of a variable first axial distance between the first fixed disk and the first floating disk;

a second conical disk pair with a second axis of rotation and with a second disk diameter, comprising an axially fixed second fixed disk and an axially displaceable second floating disk, wherein a second active circuit is adjustable by means of a variable second axial distance between the second fixed disk and the second loose disk;

a looping means for translationally transmitting a torque between the first active circle of the first conical disk pair and the second active circle of the second conical disk pair;

a first axial actuator by means of which the first axial distance is adjustable, wherein an axial first disc-actuator distance from the first disk-side surface of the first maximum effective circle to the maximum axial first end the first axial actuator is formed on the first outer side facing away from the first conical disk pair;

a second axial actuator, by means of which the second axial distance is adjustable, wherein an axial second disc-actuator distance from the second disk-side surface of the second maximum effective circle is formed to the maximum axial second end of the second Axialaktors on the second conical disk pair facing away from the second outer side;

a first shaft, which with the first cone pulley pair

torque transmitting connected and having a first sliding seat for the first floating disk; and

a second shaft, which with the second cone pulley pair

torque transmitting connected and having a second sliding seat for the second floating disk.

In the following, reference will be made to the associated, ie either first or second, axis of rotation if the axial direction, radial direction or the direction of rotation and corresponding terms are used without explicit reference. Ordinal numbers used in the preceding and following description, unless explicitly stated to the contrary, are for the purpose of distinctness only and do not represent any order or ranking of the designated components. As a rule, one of the first wave and the first one is for better clarity

Rotary axis associated component as a first component and corresponding to a second shaft and the second axis of rotation associated component referred to as a second component. If this rule is deviated, it is explicitly pointed out. Components that bear the same name but are provided with different ordinals have the same or similar functions, but are not necessarily identical. The first cone pulley pair is rotatable about the first axis of rotation and

For example, designed as input disk set. The first cone pulley pair has a first pulley diameter, which is determined in conjunction with a cone angle by the desired transmission spread. Suitable cone angles are known from the prior art and are designed accordingly by the person skilled in the art. The disk diameter therefore represents a reference to which a belt transmission is to be interpreted accordingly,

for example, with respect to the maximum absorbable forces with increasing disk diameter at the same input torque increasing

Torque load. As the torque load increases, not only the load on the conical disks per se increases, but also on the belt, which is then to be designed with a larger (radial or transverse to the direction) thickness and / or a larger (axial) width. Furthermore, the actuator forces increase because a higher axial clamping is required for holding and / or enlarging the adjacent effective circle.

The second conical disk pair is rotatable about the second axis of rotation and designed, for example, as an output disk set. The second cone pulley pair has a second pulley diameter, which is determined in conjunction with a cone angle by the desired transmission spread. For this purpose, the previous description is transferable accordingly. The disc diameter is further for the first cone pulley pair with

and for the second

Conical disk pair designated D ₂ .

Preferably, the two cone pulley pairs are designed with symmetric active circuits, so that therefore a translation spread of a minimum

Reduction, for example, with the divisor 2, via a 1: 1 translation (at the same circle of action) to a magnitude equal to maximum maximum ratio, for example, corresponding to the factor 2, ranges. Alternatively, the

Conical pulley pairs designed with different pulley diameter, so that, for example, a spread spread includes only a reduction range or a range of translations. In order to allow a most economical construction, each conical disk pair has an axially fixed fixed disk. The fixed disks of the two pairs of conical disks are to be arranged axially relative to one another in such a way that the axial offset, that is to say a course inclined to the axes of rotation, of the

Belting over the entire axial travel of the two

Conical pulley pairs, resulting from the respective adjustable axial distance, is as small as possible. The hard disks are preferred each on the

arranged opposite side of the belt, that is, when the first fixed disk is arranged on the left of the belt, the second fixed disk is arranged on the right of the belt.

The axially displaceable loose disks are axially displaceable relative to the fixed disks, so that the variable axial distance is established. As a result of the

Cone angle and the fixed width of the belt means adjusts itself to the axial distance a circle of action. The active circuits are preferably adjusted to each other in such a way that the belt is always stretched without a

Zugmittelspanner is necessary. That is, the circulation length is kept constant in accordance with the length of the belt. So if the first active circle increases, the second active circle decreases and vice versa. Radial outside is the respective maximum effective circle, which at maximum at one of the two

Tapered cone pairs and rests with minimal translation of the other cone pulley pair.

To actuate the belt drive an axial actuator is provided for each cone pulley pair, which acts electro-mechanically, so for example with a spindle, or hydraulically or pneumatically. By means of the axial actuator, the axial distance of the associated cone pulley pair is adjustable. Because hydraulic systems are often already used in the environment of a belt transmission, hydraulic operation is often preferred. However, more and more an electric hydraulic through which allows operation of the belt drive with a higher efficiency, if not permanently a pressure must be kept, but only with a change in the transmission ratio, a hydraulic fluid must be supplied with pressure. Because the axial actuator for an economical embodiment on the side of

Losscheibe is arranged, resulting in a fixed size, a disk-actuator distance, which is defined by the back of the actuator to the fixed disk. More precisely, of the respective fixed disk is the (one) end of the disk-actuator distance from the disk-side surface of the (previously described) maximum effective circle, ie a circular line about the respective axis of rotation, which can be brought on the radially outermost with the belt means in contact lying with the taper angle surface. This is preferably the radially outermost

(permissible) center line of the belt on the concerned

Conical pulley. The said back, so the (other) end of the disc-actuator distance, is a maximum axial end of the relevant Axialaktors on the side facing away from the respective conical disk pair outside. For one

hydraulic actuator, this end of the disc-actuator distance is the limit of the adjusting cylinder or Anpresszylinders, or in other words the outer surface of the bottom of a cylinder, which forms the pressure chamber for the pressure-dependent axially movable axial piston. The axial piston is connected to transmit power to the idler pulley or formed integrally with the idler pulley. And it is the part of the outer surface which is axially farthest from the fixed disk. For a mechanical actuator, this is the (corresponding maximum spaced apart) back, for example, an actuator housing or a housing for a lubricant for the sliding seat of the respective

Idler pulley. In both cases, this disc-actuator distance of

Conical pulley pair of the desired length of a travel, so at a selected cone angle of the desired ratio spread, depending.

Thus, this measure is in proportion to the

Disc diameter Di or D ₂ , short D _{1 2.} The disc-actuator distance is in the following for the first cone pulley pair as

and for the second

Conical disk pair as L ₂ , abbreviated as L _{1 2} , respectively.

So is the largest distance between the outside, facing away from the conical disk, limit of

Adjusting cylinder on the input disk set and the fixed disk of the

Input disk set on the side facing the belt. L ₂ is therefore the same measure on the output disk set. The belt transmission further comprises a first shaft and a second shaft, via which a torque can be absorbed and / or released. If, for example, the first conical disk pair is an input disk set, the first shaft is an input shaft, which is connected to a drive machine

torque transmitting connected. The second wave is then one

Output shaft, which is connected to an output torque-transmitting. In some cases, in some embodiments, a fixed or variable, preferably discretely switchable, translation gear is connected upstream or downstream.

The loose washers are connected to transmit torque to the respective shaft with relative axial movement free. This is achieved for example by means of a spline, so that an axial movement is free but a torque is transferable. Furthermore, in each case a pair of sliding seats is provided, by means of which the loose disk is axially supported against the rolling load introduced by the wrapping means. The sliding seat pair has actuator side one, first and second, sliding seat and Umschlingungsmittelseitig another, third

or fourth, sliding seat on. The sliding seats with odd

Ordinals are at the first wave and the sliding seats with straight

Ordinal numbers are located at the second shaft and those with odd ordinal numbers form the respective pair of sliding seats for storage on the first shaft and those with even ordinal numbers form the relevant one

Sliding seat pair for storage on the second shaft. The sliding seats are preferably designed as a hydrodynamic or hydrostatic sliding bearing.

The belt transmission is mainly characterized in that the ratio of the respective pulley diameter D _{1 2} to the corresponding pulley-actuator distance L _{1 2 is} equal to or greater than 1.75 [one hundred and seventy-five hundredths], for example 2.3 [twenty-three Tenth], is. The maximum achievable ratio is at least 2.5 [twenty five tenths] or above. This ratio, in short, expresses a particularly short axial

L i L ₂ L ₂

Length of each conical disk pair, because the disk diameter D _{1 2 is} greater than the disk-actuator distance L _{1 2.} According to the prior art, no ratio above 1, 70 [one hundred and seventy hundredth] is known. Thus, this embodiment are too heavy for many applications, too uneconomical and / or simply do not fit in the available axial space, so instead, for example, a discretely shiftable transmission gear is used, but which compared to a transmission with continuously variable translation on the queried dynamic, so

Speed-dependent, power spectrum disadvantageously large carbon dioxide emissions for an internal combustion engine or disadvantageously large demand for electrical energy for an electrical machine causes.

Various geometric characteristics of a belt transmission are defined as follows:

The total axial length L _{0 of} the belt transmission is the axial distance between the outside, the cone pulley pair facing away, limitation of the adjusting cylinder on the input disk set (drive) and the outside, the

Facing away from cone pulley pair, limitation of adjusting cylinder on

Output disk set (output); because they are arranged opposite each other of the belt, so right and left of it.

With L _x is to be adapted to a torque to be transmitted width of

Of course, where L _{x is of} course both on the

Input disk set as well as the output disk set is present. L _x thus corresponds to the disk distance L _var at maximum extended actuator, so the lowest allowable distance between the loose disk and fixed disk and maximum

Knitting circle. Due to the opposing axial movement of the cone _{pulley pairs} decreases in a fixed functional dependence on the increase of L _{varl 2} , and vice versa. The functional relationship is determined by the geometric conditions on the belt transmission and is for example straighter

Conical inclination non-linear and proportional with suitably curved cone inclination. The disk diameter D ₁ is the (outer) diameter of the first conical disk pair, for example, the input disk set, and the

Disc diameter D ₂ is the (outer) diameter of the second

Conical pulley pair, for example, according to the Ausgangsscheibensatzes. The (inner) diameter of the loose disk facing the end of the

Festscheibenwelle, or the large (third or fourth) sliding seat, the first cone pulley pair, for example the

Input disk set, d _lt and d ₂ is the corresponding measure in the second cone pulley pair, for example, according to the Ausgangsscheibensatz. In addition, this diameter is referred to as a sliding seat diameter.

It is as described above, a relationship between the lengths L _0, L ₂ and L _lt diameters d _lt _lt d D _2, D ₂ of the conical disk pairs. As a result, belt transmissions of different overall size can be compared or set in relation to each other.

The belt transmission proposed here has, in addition to the above

Ratio, also prefers a difference ratio of the difference of the

Disc diameter {D _{1 2} ) and the sliding seat diameter (d _{1 2} ) to the disc-actuator distance (L _{1 2} ) greater than 1, 18 [one hundred and eighteen hundredths] and less than 1, 7, for example 1, 54 [one hundred and fifty-four hundredths] , this means:

(1 )

1,18; respectively

(2) 1.7 1.18.

These difference ratios are preferred in the input disk set and

Output disk set, preferably within a tolerance of ± 2%, equal.

Particularly preferred

and L ₂ , preferably within a tolerance of ± 2%, equal. In an embodiment in which the input disk set and the

Output disc set are designed according to the above proviso, a ratio of the axial total length L _{0 of} the belt transmission is independent of the width L _{x of} the belt given, because this width L _x depends significantly on the torque to be transmitted:

for example, at 21, 3 [two hundred and thirteen tenths], or at identical execution of the two disc sets:

According to the state of the art, a value of 27.65 [two thousand seven hundred sixty-five hundredths] has hitherto been maintained.

According to an advantageous embodiment of the belt transmission, the first sliding seat and / or the second sliding seat at the same time form the

Transmission of torque by the respective loose disc are centered in an axial first overlap region with the respective axial actuator alone by means of the respective sliding seat formed as a spline.

Furthermore, in an advantageous embodiment of the sliding seat of the loose disk for torque-driven, designed by means of a toothing. Conventionally, a, so-called small, sliding seat axially Aktorseitig and another, so-called large, sliding seat side disc provided. The two

Sliding seats form a bearing in the form of a plain bearing against the tensile force of the belt on the cone pulley pair, or on the

Idler pulley. The sliding bearing is preferably designed low friction as hydrodynamic or hydrostatic sliding bearing. Furthermore, a spline is conventionally provided for the torque transmission, which is often placed between the two sliding seats. Here it is now proposed to form the spline at the same time as a sliding seat, so that as a result of the integration of this function axial space is gained. This is achieved by the fact that the toothing is designed in such a way that such a slight radial clearance is provided by way of the tooth tip, tooth root contact and / or tooth flank contact, that sliding is not prevented, but adequate centering is achieved. Preference is given to a guide over the tooth head

or the corresponding tooth base in each case only one of both at the tooth pairing of the spline for the Zahnkopf-Zahngrund- contact established. That is, for example, the internal teeth has on their teeth in each case a tooth head, which is adapted for radial contact with a corresponding tooth root of the external toothing of the spline. In the teeth of the external teeth but then the respective tooth head for such a large radial distance to the corresponding tooth base of

Internal teeth set up that only the aforementioned tooth heads are brought into contact with the internal teeth. As a result, there is no double fit. In contact here means that these contact partners, preferably on one

Lubricant film, sliding against each other.

This spline preferably replaces the actuator-side, so-called small, sliding seat. In this embodiment, the axial rear wall of the actuator, preferably the pressure chamber, directly adjoins this spline.

As an alternative or in addition, the large sliding seat preferably adjoins the splined end of the splined side preferably directly on the spline side.

According to an advantageous embodiment of the belt drive both conical disk pairs are purely electro-mechanically, hydraulically or pneumatically actuated.

According to this embodiment is in an advantageous embodiment of a mechanical biasing element, for example, a compression spring in

Output disk set, omitted. As a result, the structure is axially more compact and less expensive. It should be noted that with the waiver of one Mechanical biasing element is not understood here that no strained, for example, employees employed in O arrangement, storage is provided. On the contrary, a tense storage is often favorable for a small axial space requirement and the (intrinsic) travel of the tense storage is usually not relevant space. For a suitable biasing element, however, a minimal axial spring travel is maintained. By dispensing with this biasing element, therefore, axial space is obtained. That means the concerned

Losscheibe at an axial actuator in a powerless state, such as unpressurized filling of the pressure chamber, indifferent, so free to move, is. So far, it has been desired that the belt transmission is automatically transferred with the system off in the lowest gear ratio, comparable to the first gear of a (discrete) gearbox. The least translation is from the

Considered drive side to the output side and refers to the

Rpm ratio. This is for example in a motor vehicle an advantageous state when the motor vehicle is to be pushed in the workshop with the system off. This was done by means of a compression spring on

Guaranteed output disc set. It has now been found that such a function is not necessary, on the one hand being provided in many applications, a releasable torque coupling, which is solved for a corresponding need. In an electrified drive train, for example, a purely electric drive train or a hybrid drivetrain comprising an internal combustion engine, often alone the electric machine is permanently, ie fixed, connected to the output. As long as no electric current flows in the electric machine, the resistance is so low there that a low gear ratio is not required to move a motor vehicle with the system off by hand. It is also not necessary to solve a torque clutch. If an internal combustion engine is present, this is, for example, normally detached from the drive train and / or connected solely via a torque converter with the output. The resistance of the internal combustion engine is therefore not relevant or very low.

According to an advantageous embodiment of the belt drive, the first axial actuator and the second axial actuator are hydraulically actuated and in the

Cooperation with a first pressure surface of the first floating disk of the first Axial distance is variable or in cooperation with a second pressure surface of the second floating disk, the second axial distance is variable, wherein radially inward at least one of the sliding seats and radially outside the corresponding floating disk is axially sealed to the respective fixed disk.

In this advantageous embodiment, a leakage of lubricant and / or hydraulic fluid is significantly reduced. This is advantageous not only in terms of reducing consumption or lubricant sales, but allows a dry version of the belt transmission. This makes it possible to arrange without intermediate housing electrical components, in particular an electric motor, axially and / or radially close to the cone pulley pairs, and thus to gain axial and / or radial space. In previously known belt transmissions, an outflow of hydraulic fluid via the large sliding seat is accepted as well as provided on the outer circumference of the loose disk, so the piston surface in the pressure cylinder, only a piston ring with circumferential gap. About this gap, which holds a resilient fit between loose disc and pressure cylinder, falls to a significant outflow of hydraulic fluid. Thus, the turnover of hydraulic fluid is very high. The seals, so the sliding seat seal and the piston seal are according to the present proposal as a closed rings, ie without circumferential gap, for example, as O-rings executed. The leakage is very low. At the hydraulic

Embodiment is the hydraulic pressure system and adjustment system with the actuator, for example, by means of a (known) full hydraulics operable. Alternatively, a so-called electric pump actuator (EPA) can be used. Such an electric pump actuator consists essentially of a pump, which is driven by a controlled electric motor, and a local control unit. The pump is usually designed as a reversing pump. Pump, electric motor, eventually required valves and the control electronics and control electronics with sensors (angle sensors, rotation sensors and pressure sensors) are all in one

housed common transmission housing. This creates a compact unit, which is flexible at different positions on a transmission or to a

Clutch operation is mountable. There are only two connections for

Pressure medium, namely suction connection and pressure connection, whose function in a reversing change, as well as connections for a power supply and possibly a higher-level control necessary. If such an electric pump actuator for actuating the cone pulley pair, or the

Variators used, it is advantageous to provide a sealed sliding seat and leak-free main seals. Since the electric pump actuator does not have a large pump sump, but only a small reservoir, by means of the seal towards the fixed disk, preferably at the so-called large sliding seat, the required amount of the hydraulic medium to be delivered

reducible or the performance of the electric pump actuator can be reduced.

Cooperation with a first pressure surface of the first idler pulley, the first axial distance is variable or in cooperation with a second pressure surface of the second idler pulley, the second axial distance is variable, arranged at least one cone pulley pair an opening for a hydraulic fluid for the respective Axialaktor axially overlapping with the respective sliding seat is.

By the opening for the intake and / or discharge of hydraulic

Liquid is integrated into the sliding seat, axial space is gained. In addition, a good lubrication of the corresponding sliding seat is preferably achieved. This is particularly advantageous for the above-mentioned embodiment, in which the (small) sliding seat at the same time comprises the spline and thus the opening is arranged in the region of the spline. Because there is the largest inflow pressure at the opening, this ensures that the spline is always adequately supplied with lubricant, namely the hydraulic fluid.

Particularly preferably, the opening is arranged axially between the splines and the (large) third and fourth sliding seat, so that both sliding seats of the respective shaft are optimally supplied with lubricant.

According to an advantageous embodiment of the belt drive, the first axial actuator and the second axial actuator are hydraulically actuated and in the Cooperation with a first pressure surface of the first floating disk, the first axial distance is variable or in cooperation with a second pressure surface of the second floating disk, the second axial distance is variable, the two pressure surfaces are the same size.

Particularly preferred are the pressure surfaces for adjusting the disc spacing or for pressing on both disc sets, so on

Input disk set and the output disk set the same size. In addition, the sheet metal parts and the travel plates, so the loose wheels, the two disc sets are identical, so that can be reduced with common parts costs. In addition, the same or similar is for both cone pulley pairs

Measuring electronics can be used, so that particularly preferably a common system for controlling and can be used. This has cost advantages and also prefers space advantages, because it can be dispensed with a double version of the transmitter.

According to an advantageous embodiment of the belt transmission, the first and second axial actuators and the first and second idler pulleys are identical in construction.

Thus, the axial actuators and the loose washers of the two disc sets are identical, so that costs can be reduced due to a high number of identical parts. According to one embodiment, the two cone pulley pairs and, most preferably, other components such as seals, bearings and

Gear housing, identical on both disc sets, so that corresponding cost advantages and development advantages and control advantages in operation can be achieved.

According to an advantageous embodiment of the belt transmission

overlap the two axial actuators radially outward with the other conical disk pair radially and axially adjacent to the other fixed disk.

It is desirable to keep the distance between the cone pulley pairs as low as possible, which not only brings advantages in terms of space, but this is also the shortest possible means of belt can be used. With a short Belting means is the rotating mass and the noise resulting from the chain oscillation, perceived as disturbing. Here it is now proposed that the two cone pulley pairs are brought radially almost to contact, so that only a small radial gap remains, which is a

ensures contactless operation under all design loads.

The same applies to the axial distance, which is reduced to an equally small gap. The gap dimensions may vary depending on the load, depending on the load.

According to a further aspect, the invention relates to a drive train, comprising a drive unit with an output shaft, at least one consumer and a belt transmission according to an embodiment according to the above

Description, wherein the output shaft for torque transmission by means of the belt drive is connectable to the at least one consumer with continuously variable transmission,

wherein preferably the drive unit comprises at least one electric machine, wherein at least one of the electric machines is integrated in a transmission housing of the belt transmission.

The powertrain is configured to be one of a power plant, for

Example of an internal combustion engine or an electric motor, provided and output via its output shaft torque for use

to be transferred according to demand, ie taking into account the required speed and the required torque. One use is, for example, an electrical generator for providing electrical energy. In order to selectively transmit the torque and / or by means of a gearbox with different ratios, the use of the belt transmission described above is particularly advantageous because a large spread in a small space is achievable. Conversely, a recording of an inertial energy introduced by, for example, a drive wheel, which then forms a drive unit in the above definition, is also applied to one by means of the belt drive

electric generator for recuperation, so the electrical storage of braking energy, with a correspondingly equipped

Torque transmission train can be implemented. Furthermore, in a preferred Embodiment provided a plurality of drive units, which are operable in series or in parallel or decoupled from each other and their torque by means of a belt transmission according to the above

Description can be made available as needed. Examples are hybrid drives of electric motor and internal combustion engine, but also multi-cylinder engines in which individual cylinders (groups) are switchable.

The belt transmission proposed here has a particularly small overall size and can therefore be used economically in a large number of different drive trains.

According to a further aspect, the invention relates to a motor vehicle, comprising at least one drive wheel, which by means of a drive train after a

Embodiment according to the above description is drivable.

Most motor vehicles today have a front-wheel drive and sometimes 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 direction of travel. The radial space is especially small in such an arrangement and it is therefore particularly advantageous to use a belt drive small size. Similarly, the use of a belt transmission in motorized two-wheeled, for which a significantly increased performance at

constant space is required.

This problem is exacerbated in passenger cars of the small car class according to European classification. The used aggregates in one

Passenger cars of small car class are not significantly reduced compared to passenger cars larger car classes. Nevertheless, the available space for small cars is much smaller. In the motor vehicle proposed here with the drive train described above such a small space is required that the belt transmission exceeds not only in terms of its efficiency over the total speed range, but also in terms of its space requirements a conventional (discrete) manual transmission. 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 Ka + or Renault Clio. Well-known full hybrids in the small car class are the BMW i3, the Audi A3 e-tron or the Toyota Yaris Hybrid.

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

Fig. 1: a compact construction Umschlingungsgetriebe; and

Fig. 2: a hybrid powertrain in a motor vehicle with

Variable transmission.

Fig. 1 shows a compact belt transmission 1, or such a variator, with a trained example as input disk set first cone pulley pair 3 with a first axis of rotation 5, comprising a first fixed disk 9 and a first floating disk 11, as well as an example

Output disk set formed second conical disk pair 4 with a second axis of rotation 6 and with a second fixed disk 12 and a second

Losscheibe 12. The two fixed disks 9 and 10 are each axially fixed and rotationally fixed, that is unsolvable torque transmitting, here for example in one piece, for example, formed as an input shaft first shaft 30 or a formed for example as an output shaft second shaft 31. The two conical disk pairs 3 and 4 are executed by means of a chain here as a chain Belting means 17 with continuously variable transmission

connected torque transmitting. The idler pulleys 11 and 12 are axially displaceable relative to the respective fixed disk 9 or 10 and have for this purpose an axially displaceable connection to the first shaft 30

or to the second shaft 31. Here, in the illustration on the left, a (smaller) first sliding seat 32 is formed at the first shaft 30, which at the same time forms the first spline 36. Likewise, in the illustration on the right, a (smaller) second sliding seat 33 is formed in the second shaft 31, which at the same time forms the second spline 37. These sliding seats 32 and 33 are thus adapted for torque driving and for axial displacement of the respective loose washers 11 and 12. Each axially adjacent to the fixed disk 9 or 10 is a (large) third sliding seat 34 with the first

Sliding seat diameter 79 and fourth sliding seat 35 formed with the second sliding seat diameter 80. This is axially towards the respective

Fixed disk 9 or 10 by means of a first sliding seat seal 64 and a second sliding seat seal 65 toward the

Strapping 17 sealed. Furthermore, on the outer circumference of

Losscheiben 11 and 12, a first piston seal 66 and a second piston seal 67 are provided. For this purpose, the optional sealing elements, more precisely, the first sliding seat seal 64 and the first piston seal 66 and the second sliding seat seal 65 and the second piston seal 67, are provided, which are designed for example as an O-ring. This seal is advantageous for use in an electrified drive, so that an electric drive does not have to be housed separately, but thereby already a sufficiently dry environment is created. For example, this allows one

to integrate electric drive in a gearbox of the variator.

For axially moving the first idler pulley 11, a hydraulic first axial actuator 18 is provided here, which has a first pressure chamber 57, also (first).

Cylinder space, between the (back) first pressure surface 20 of the first floating disk 11 and the first pressure cylinder 59 with a first cylinder bottom 61 includes. Via a first opening 38, the first pressure chamber 57 can be pressurized by means of a hydraulic fluid. This is the first one

Axial distance 13 adjustable, which defines here at the maximum first active circuit 52 is. In the illustrated state, the first axial distance 13 corresponds to the width 81 of the belt 17, because here the maximum first active circle 52 is set, and the axial distance 13 is thus shown in its minimum length, so that the present first effective circle 15 corresponds to the first maximum effective circle 52 ,

For axial movement of the second floating disk 12, a hydraulic second axial actuator 19 is provided here, which a second pressure chamber 58, also called (second) cylinder space between the (rear) second pressure surface 21 of the second floating disk 12 and the second pressure cylinder 60 with a second

Cylinder bottom 62 includes. Via a second opening 39, which is here formed in a second overlapping region 55 axially overlapping with the first spline 36, the second pressure chamber 58 can be pressurized by means of a hydraulic fluid. As a result, the second axial distance 14 is adjustable, which is defined here at the maximum second active circle 53. In the illustrated state, the second axial distance 14 is wider than the belt 17 and is

Corresponding to the first conical disk pair 3 shown in its maximum length, so that therefore the present second active circuit 16 is minimal.

By means of the pressure chambers 57 and 58, the respective axial distance 13th

or 14 between the associated fixed disk 9 or 10 and the respective floating disk 11 or 12 adjustable, and the contact pressure, so the friction force to the respective surfaces of the respective fixed disk 9, 10 and loose disk 11, 12 of the belt 17 between the conical disk pairs 3 and 4 adjustable ,

Characteristics of the belt drive 1 are the first pulley diameter 7 (Di) and the second pulley diameter 8 (D ₂ ), which in

Interaction with the first sliding seat diameter 79 (di) or with the second sliding seat diameter 80 (d ₂ ) defines the transmission spread at a selected cone angle of the conical disk pairs 3 and 4. The size of the sliding seat diameter 79, 80 (d _{1 2} ) is determined for example by the torque to be transmitted. Furthermore, in conjunction with the width of the belt 17 (L _x ), this results in the first axial _distance 13 (L _varl ) and the second one

_{Axial distance} 14 (L _var2 ) for the first _{effective circle} 15 and the second Active circuit 16. In order to be able to operate this ratio spread, the first axial actuator 18 or the second axial actuator 19 must have a corresponding actuating length, which is in the first disk-actuator distance 22 (L _x ) or the second disk-actuator distance 23 (FIG. L ₂ ) precipitates. The first disk-actuator spacing 22 is formed between the first end 26, which is formed by the first outer side 28 here on the first cylinder bottom 61, and the first disk-side surface 24 at the first maximum effective circle 52. The second disc-actuator distance 23 is between the second end 27, which is formed by the second outer side 29 here on the second cylinder bottom 62, and the second disc-side surface 25 at the second maximum

Active circuit 53 formed. The disc-actuator distances 22 and 23 are therefore

unchangeable. The two cone pulley pairs 3 and 4 are now, preferably for a minimal restriction of the belt 17 over the entire

Translation spread, fixed to each other, so that a

Total construction length 56 (L ₀ ). As a result of the above measures, this is axially particularly compact. In addition, due to the radial overlap 63 of the respective fixed disk 9, 10 and the respective other axial actuator 19 and 18, here even with the floating disk 10 and 9, a high radial compactness is achieved.

In Fig. 2 is a drive train 2, which is designed here as a hybrid powertrain, shown schematically in a motor vehicle 44. The drive train 2 is here arranged transversely to the longitudinal axis 48 behind the driver's cab 47 of the motor vehicle 44. The powertrain 2 includes an internal combustion engine 50 having a

Verbrennerwelle 72, which here forms the drive unit 40, which is continuously connected by means of a belt transmission 1, that is continuously, translating with the output formed here by the left drive wheel 45 and a right drive wheel 46. Here is advantageously one

Dual mass flywheel 73 interposed, so excessive

Rotationsunctions are damped out before the torque is passed into the belt transmission 1. Furthermore, a hybrid module 51 is provided with a module shaft 70, the module axis 86 is arranged here parallel to the motor shaft 49. And last (optional) is still an electric drive machine 42 is provided with a rotatable about the rotor axis 69 rotor shaft 78, which here also (optionally) is arranged parallel to the motor shaft 49, the first

Conical disk pair 3 and the second conical disk pair 4 are connected to each other by means of a belt 17 to transmit torque and housed in a common gear housing 43, wherein here preferably the pumping device together with the (respective) electric drive in the

Gear housing 43 is arranged. Here, optionally by means of a chain drive 74, the second cone pulley pair 4 with, optionally here by means of a

Planetary gear 71 translated module shaft 70 permanently or separable, for example, by means of the hybrid clutch 75, torque transmitting connected. The hybrid module 51 and / or the internal combustion engine 40 are separably connected by means of the hybrid clutch 75 with a differential 77 torque transmitting. The electric drive machine 42 is connected to its rotor shaft 78 by means of a spur gear 76, here (optional) permanently connected to the differential 77 torque transmitting. A longitudinal arrangement is also possible, in particular with the belt transmission 1 shown in FIG. 1, as well as a coaxial arrangement of at least two of the machines 40, 42 and 51.

The belt transmission proposed here has a particularly small size and is therefore particularly economical.

Reference list of belt transmissions

powertrain

first conical disk pair

second cone pulley pair

first axis of rotation

second axis of rotation

first disc diameter

second disc diameter D ₂

first hard disk

second hard disk

first loose disk

second loose disk

first axial _distance L _varl

second axial _distance L _var2

first circle of action

second circle of action

endless

first axial actuator

second axial actuator

first printing surface

second printing surface

first disc-actuator distance

second disc-actuator distance L ₂

first disk-side surface second disk-side surface first end

second end

first outside

second outside

first wave

second wave

first sliding seat second sliding seat

third sliding seat

fourth sliding seat

first spline second spline first opening

second opening

power unit

drive shaft

electric machine

gearbox

motor vehicle

left drive wheel

right drive wheel

cab

longitudinal axis

motor axis

Internal combustion engine

hybrid module

first maximum active circle second maximum effective circle first overlapping zone second overlapping zone Total structural length L ₀

first pressure chamber

second pressure chamber

first impression cylinder

second pressure cylinder first cylinder bottom

second cylinder bottom radial overlap

first sliding seat seal second sliding seat seal first piston seal second piston seal

module axis

rotor axis

module shaft

planetary gear

Verbrennerwelle

Dual Mass Flywheel

chain level

hybrid clutch

Spur gears

differential

rotor shaft

first sliding seat diameter

second sliding seat diameter d ₂ width of the belt L _x

Claims

claims

1. belt transmission (1) for a drive train (2), comprising at least the following components:

a first conical disk pair (3) with a first axis of rotation (5) and with a first disk diameter (7), comprising an axially fixed first stationary disk (9) and an axially displaceable first idler disk (11), wherein by means of a variable first axial distance (13 ) between the first fixed disk (9) and the first loose disk (11), a first active circuit (15) is adjustable;

a second conical disk pair (4) with a second rotation axis (6) and with a second disk diameter (8), comprising an axially fixed second fixed disk (10) and an axially displaceable second floating disk (12), wherein by means of a variable second axial distance (14 ) between the second

Fixed disk (10) and the second loose disk (12), a second active circuit (16) is adjustable;

- A wrapping means (17) for translationally transmitting a torque between the first active circuit (15) of the first

Conical pulley pair (3) and the second active circuit (16) of the second

Cone pulley pair (4);

- A first axial actuator (18), by means of which the first axial distance (13) is adjustable, wherein an axial first disc-actuator distance (22) from the first disk-side surface (24) of the first maximum effective circle (52) to the maximum axial first end (26) of the first axial actuator (18) is formed on the first conical disk pair (3) facing away from the first outer side (28);

- A second axial actuator (19), by means of which the second axial distance (14) is adjustable, wherein an axial second disc-actuator distance (23) from the second disk-side surface (25) of the second maximum

Active circle (53) to the maximum axial second end (27) of the second axial actuator (19) on the second conical disk pair (4) facing away from the second outer side (29) is formed;

a first shaft (30) connected to the first conical disk pair (3)

having a torque transmitting connected and a first sliding seat (32) for the first floating disk (11); and a second shaft (31), which is connected to transmit torque to the second conical pulley pair (4) and has a second sliding seat (33) for the second loose pulley (12),

characterized in that

in both conical disk pairs (3,4) the ratio of the respective

Disc diameter (7,8) to the corresponding disc-actuator distance (22,23) is equal to or greater than 1, 75.

2. belt transmission (1) according to claim 1, wherein the first sliding seat (32) and / or the second sliding seat (33) at the same time form the torque transmission by the respective loose disk (11, 12) in an axial first

Intersection region (54,55) with the respective axial actuator (18,19) alone by means of the respective as a spline (36,37) formed

Sliding seat (32,33) are centered.

3. belt transmission (1) according to claim 1 or 2, wherein both

Conical pulley pairs (3,4) purely electro-mechanically, hydraulically or pneumatically actuated.

4. belt transmission (1) according to any one of the preceding claims, wherein the first axial actuator (18) and the second axial actuator (19) are hydraulically actuated and in cooperation with a first pressure surface (20) of the first

Losscheibe (11) the first axial distance (13) is variable or in cooperation with a second pressure surface (21) of the second floating disk (12) of the second axial distance (14) is variable, wherein radially inside at least one of the sliding seats (34,35) and radially outside the corresponding loose disk (11, 12) is sealed axially towards the respective fixed disk (9,10).

5. belt transmission (1) according to any one of the preceding claims, wherein the first axial actuator (18) and the second axial actuator (19) are hydraulically actuated and in cooperation with a first pressure surface (20) of the first

Losscheibe (11) the first axial distance (13) is variable or in cooperation with a second pressure surface (21) of the second floating disk (12) of the second axial distance (14) is variable, wherein at least one cone pulley pair (3,4) an opening (38,39) for a hydraulic fluid for the respective axial actuator (18,19) axially overlapping with the respective sliding seat (32,33) is arranged.

6. belt transmission (1) according to one of the preceding claims, wherein the first axial actuator (18) and the second axial actuator (19) are hydraulically actuated and in cooperation with a first pressure surface (20) of the first

Losscheibe (11) the first axial distance (13) is variable or in cooperation with a second pressure surface (21) of the second floating disk (12) of the second axial distance (14) is variable,

wherein the two pressure surfaces (20,21) are the same size.

A belt transmission (1) according to any preceding claim, wherein the first and second axial actuators (18, 19) and the first and second

Losscheiben (11, 12) are identical.

8. belt transmission (1) according to any one of the preceding claims, wherein the two axial actuators (18,19) radially overlap radially with the other conical disk pair (4,3) radially and axially adjacent to the respective other fixed disk (10,9).

9. powertrain (2), comprising a drive unit (40) with a

Output shaft (41), at least one consumer (45,46) and a

The belt transmission (1) according to one of the preceding claims, wherein the output shaft (41) for transmitting torque by means of

Belt transmission (1) can be connected to the at least one consumer (45, 46) with a continuously variable transmission,

wherein preferably the drive unit (40) at least one electrical

Machine (42), wherein at least one of the electrical machines (42) in a transmission housing (43) of the belt transmission (1) is integrated.

10. Motor vehicle (44), comprising at least one drive wheel (45,46) which by means of a drive train (2) according to claim 9 is drivable.