DE102005037923A1 - Spherical disk-shaped enveloping gear system e.g. for vehicle, has conical disk on power input side and pair of conical disks on output side, each disk pair has axially fixed disk and axially movable disk - Google Patents

Abstract

The system has a conical disk on a power input side and a pair of conical disks on an output side, each disk pair has an axially fixed disk and an axially movable disk. The disks are carried on shafts on respective shafts on the power input side and on the output side. An endless torque-transmitter extends between and passes around each disk pair for transmitting torque between them. The axially movable disk has a slide seat positioned inwardly and adjacent to its associated shaft, and an axially movable disk has a slide seat positioned radially outwardly of an inner slide seat, for minimizing axially movable disk tilting relative to its associated shaft when the transmission is under load. The axially movable pulley includes three slide seats and the radially outwardly positioned slide seat forms part of a centrifugal oil cover. The slide seats are provided on a conical disk pair on the power input side and the conical disk pair on the output side. An independent claim is included for a method for production, and a vehicle comprising such a gear system.

Description

The invention relates to an automatic transmission in the form of a conical-pulley, as it is for example from the DE 10 2004 015 215 and other publications, as well as a method for its production and a vehicle equipped therewith.

automatic transmission in the broader sense, identifier converters whose instantaneous translation is itself independent dependent on from current or expected operating conditions, such as partial load, Thrust and environmental parameters, such as temperature, air pressure, Humidity, gradually or continuously changed. They include such Identification transformers operating on an electric, pneumatic, hydrodynamic, hydrostatic Principle or on a principle mixed from these principles based.

The Automation refers to a variety of functions, such as the approach, the translation choice, the nature of the translation change in different operating situations, where under type of translation change to For example switching one step at a time, skipping be understood by switching stages and the speed of adjustment can.

Of the Desired for comfort, safety and reasonable construction costs the degree of automation d. H. how many functions run independently.

In As a rule, the driver can intervene manually in the automatic sequence or him for limit individual functions.

Automatic transmissions in the narrower sense, as they are used today mainly in vehicle construction, usually have the following structure:
On the drive side of the transmission there is a starting unit in the form of a controllable clutch, for example a wet or dry friction clutch, a hydrodynamic clutch or a hydrodynamic converter.

To A hydrodynamic converter often uses a lock-up clutch in parallel with the pump and turbine part connected by direct power transmission increases the efficiency and by defined slip at critical Speeds dampening the vibration.

The Starting unit drives a mechanical, stepless or stepped Change gearbox having a forward / reverse drive unit, a main, range, Split group and / or a variator may contain. Gear transmission groups depending on the requirements of smoothness, space and transmission options, in countershaft or planetary design with straight or helical gearing designed.

The Output element of the mechanical transmission, a shaft or a Gear, drives directly or indirectly via intermediate shafts or a Intermediate stage with a constant gear ratio to a differential gear, which can be designed as a separate transmission or an integrated Part of the automatic transmission is. Basically, the gear is suitable for longitudinal and Cross installation in the vehicle.

to Adjustment of the translation In the mechanical transmission are hydrostatic, pneumatic and / or provided electrical actuators. A hydraulic pump after works the principle of repression, supplies pressure oil for the Starting unit, in particular the hydrodynamic unit, for the hydrostatic Control elements of the mechanical transmission and for the lubrication and cooling of the System. Depending on the required pressure and delivery volume gear pumps, Screw pumps, vane pumps and piston pumps, the latter mostly in radial design, in question. In practice, gear pumps and radial piston pumps have for this Purpose enforced, the gear pumps because of their low Construction costs and the radial piston pump because of the higher pressure levels and provide better controllability benefits.

The Hydraulic pump can be anywhere on the gearbox one constantly arranged by the drive unit driven main or secondary shaft be.

It Are stepless automatic transmissions known, consisting of a starting unit, a planetary reversing gear as a forward / reverse drive unit, a hydraulic pump, a variator, an intermediate shaft and a differential. Of the Variator in turn consists of two conical disk pairs and one Encircling. Each conical disk pair consists of one in axially displaceable second conical disk. Between these Cone pairs of discs is running the belt, for example a push belt, a Pull chain or a belt. about the adjustment of the second conical disk changes the running radius of the Umschlingungsorgans and thus the translation of the stepless Automatic transmission.

Infinitely variable automatic transmissions require a high pressure level to the conical disks of the variator in all operating points with the desired To be able to adjust speed and also with a sufficient base pressure largely wear-free to transmit the torque.

at For motor vehicles, the need for comfort is generally very high, especially with regard to acoustics. The driver and the inmates want especially in motor vehicles of the upscale category no disturbing noises coming out the operation of the aggregates of the motor vehicle arise. The internal combustion engine and other units such as gearbox but produce sounds that largely disturbing could be felt. For example, it can be used with continuously variable transmissions when using a link chain to make a noise, because such a link chain due to their construction with tabs and bolt in the operation of the transmission a repetitive shock by the impact of the bolts on the conical disks of the gearbox generated. Acoustic effects usually occur in CVT transmissions this impulse ("impact") as a suggestion attributed. This acoustic excitation then generates resonances at the natural frequencies of the gearbox (FE modes) or waves (torsional modes, bending modes).

One further acoustic effect comes from the CVT chain, which in the tense Strand or strand can swing like a page, which z. B. by a slide is obstructable. Torsional friction vibrations are for example, as plucking at frequencies of 10 Hz of couplings known here. When the friction coefficient under slip change such is that the coefficient of friction drops, plucking is excited. in this connection is primary in automatic transmissions the steel-paper coefficient of friction relevant.

A The invention is based sub-task is the acoustics to improve such a transmission and thus the comfort in particular the noise comfort a vehicle equipped with such a transmission to improve. Another sub-problem underlying the invention is that after the analysis of high-frequency, strong CVT oscillations and the hanging together with it clarification the corresponding mechanisms of action to present suitable countermeasures around these vibrations, predominantly in the acoustic field in of the order of 400-600 Hz, to minimize or possibly to prevention. A further sub-task of the invention is increase the durability of components and thus the service life to extend such an automatic transmission. Another subtask the invention is based, the torque transmission capability To increase such a transmission or greater forces through the components of the Transmission transmitted to be able to. Besides - such a additional subtask - should Such a transmission can be manufactured economically.

The Task parts are characterized by those set forth in the claims as well as in the Description also in connection with the figures explained invention solved with their developments.

Out The analysis results in a simulative understanding of Type of vibration, which is a movement of the chain in the loop coupled with a tilting and / or bending the respective distance disc acts. Determining for the frequency of the vibrations are first the chain mass and the total tilting and bending stiffness of the windscreens. This rigidity is understood including the disc spreading in itself, tilting of disks, deflection of waves due to their elasticity and the inclination the waves due to different Lagersteifigkeiten. Farther are the Reibwertniveau and the Reibwertverlauf as well as the speed and the translation Determining frequency.

These Insights are surprising in that because vibrations of the chain in the loop, so during their Clamping in the pulley set, so far not described and also the previously held opinion that in the sheets of frictional contact with the Conical disks inhibits such oscillations, contradicts.

Also an influence of the CVT oil on such friction vibrations is not yet described, so that these oils So far only on high and temporally stable coefficient of friction and low wear developed were.

It Although it is known that the sliding CVT cone pulleys (Wegscheiben) a tilting play between shaft and distance disc one Influence on the efficiency has, however, are so far no swinging Bending, tilting or wobbling movements of the windscreens described.

In CVT transmissions in the form of belt pulley belt transmissions with a belt, in particular with chain, the conical disks of the variator are deformed by the contact forces against the belt. These contact forces are required, on the one hand to prevent slippage of the chain in the transmission of torque and on the other hand to adjust the translation of the variator and thus the transmission and change. The wedge-shaped gap, which form the halves of the conical disk, is thereby changed under load. Taking into account the shape of the conical disks and the position of the correspond the load application points of the belt, the wedge gap is then deformed most from the non-loaded position when the resulting from the contact force against the belt is largest and the corresponding force application points are located radially outward, ie the largest possible diameter. In a CVT in the form of a conical pulley, the force application points of the belt or the chain or the thrust belt are largely determined by the translation of the variator. It should also be noted that the points of application of force do not act on the conical disks over the entire circumference of 360 °, but only in an angular range which is limited by the corresponding ratio and thus smaller. This results in an asymmetrical arrangement of the cone pulley halves, as will be explained in more detail later.

By this uneven plate and the uneven load sharing within the belt, is the belt means when passing the loop on the conical disk a radial Movement forced towards the center of the shaft. hereupon also has the direction of rotation influence, since the conditions are dependent on whether the considered of chain Part of the load strand or the return strand is.

ever bigger the Load, the more pronounced occur these deformations and the greater the frictional forces and Friction paths that arise as a result. This friction leads to efficiency losses and wear and tear also works as an excitation mechanism for Friction vibration. The friction vibrations can turn, for example by structure-borne sound excitations, Sounds produce.

Of the for the Interpretation most critical case for the effects described above are when starting with a bevel gear given at the output side cone pulleys. In the starting process is namely the load from the drive maximum, as well as the contact pressure on the belt by the appropriate translation slow. Through this translation is the belt or the chain on the output side Cone pulleys radially maximum far outside. By this burden the driven side pulleys are strongly deformed or very strongly pushed apart, so that the wedge gap becomes very large, resulting in maximum friction and friction forces.

According to the invention contributes to the solution of Task and to improve transmissions according to the prior art, in which, for example, the four conical disks geometric terms Plate shape and stiffness similar accomplished are a conical-pulley transmission with drive-side and output side cone pulley pairs, each a solid disk and a Wegscheibe, each on a drive side and a driven-side shaft and arranged via a belt are connectable, wherein the conical-pulley a stiffness-optimized variator has.

Farther contributes to solution the task and to improve transmissions according to the prior art a conical-pulley transmission with drive-side and output side cone pulley pairs, each a solid disk and a Wegscheibe, each on a drive side and a driven-side shaft and arranged via a belt for torque transmission can be connected, wherein a sliding seat at least one spacer in the radially inner region and at least one sliding seat at least a travel disc is arranged in the radially outer region thereof.

In the wave near sliding seat arrangements, as they are, for example, in 1 and in the 8a and 8b are shown, the length of the entire set of discs is determined inter alia by the length of the conical disk and the subsequent components, the sliding seats have an effect on the conical disk length. If one of the sliding seats displaced radially outward, the following components can be arranged under the sliding seat, so that they come to lie radially within the radially outer sliding seat, whereby axial space can be saved. In this space radially within this sliding seat can accommodate, for example, the storage of the pulley set, a part of the housing with the rotary inlets for fluid supply of the respective pulley set, a hydraulic pump or a drive unit for a hydraulic pump.

Farther is it possible, for example, the newly added space in the inner area for a transfer case to use an all-wheel arrangement.

It can be particularly advantageous in a conical-pulley transmission according to the invention, if the travel disc has two sliding seats, while it may be advantageous, for example in terms of rigidity, if the travel disc has three sliding seats, as z. In 10 shown and described in this context.

It may also be advantageous if a centrifugal oil hood is formed using the radially outer sliding seat, where can be obtained by, for example, in the radially inner region additional space.

at a conical-pulley transmission according to the invention can the sliding seat assembly on the drive side and / or output side cone pulley pair be provided.

There the additional necessary axial space length the sliding seat, which consists of an extension of the sliding seat Seal results, is not space-defining, the radial Outside arranged sliding seat by an axially adjacent him arranged Seal to be sealed.

Generally it can be in a conical-pulley transmission according to the invention be beneficial to the storage of the travel disc radially inside of the radially outside to arrange arranged sliding seat.

Advantageous z. B. in terms of manufacturing design it may be when the radially outside arranged sliding seat using a component formed which is connected to the path plate, this connection a welded joint can be.

In addition, can a centrifugal oil hood are formed using this component, the to the speed-dependent Fliehölkompensation can be used, with two centrifugal oil chambers can be formed to an even higher centrifugal oil compensation to reach.

Especially it can be advantageous if the rigidity acts radially outward Force at the output side pulley set much larger than at drive side executed is, where it can prove to be an advantage when the stiffness is executed by a factor of 1.2 to 1.6 larger.

It may also be advantageous if the output side plate a much higher one Stiffness than the drive-side deflection plate.

at a conical-pulley transmission according to the invention can It may be advantageous if the driven side pulleys a geometrically much more massive conical disk than the drive side Have conical disks.

Farther it may be appropriate if the output side plate a geometrically much massive Cone pulley neck as the drive-side deflection plate has.

It may prove to be advantageous if the output side windscreen a geometrically much more massive cone disc plate than the has output side fixed disk.

From Advantage may be, if the drive-side travel disc a geometrically much more solid cone disc plate than the drive-side fixed disc having.

It may also be useful if the output side plate a smaller on average leadership game has as the drive-side deflection plate.

Farther It may be advantageous if the output side plate a significantly longer large leadership seat has as the drive-side deflection plate.

Appropriately it should be, if at least one spacer disc at least one piece with you executed Having sealing career.

It may also be advantageous if at least one shim two having directly connected sealing raceways.

ever according to embodiment it may be appropriate to manufacture the sealing raceway by machining or without cutting.

Farther can in collapsed condition in addition to the at least one sealing point a free area may be provided, which can serve as a dirt room.

at a conical-pulley transmission according to the invention It may be advantageous if the output side plate a cylindrical conical disc neck, wherein the conical disc neck can serve as spring centering, and / or if the conical disk neck has a half-round groove, which can serve as a spring system.

Generally It may be advantageous if the output-side spacer a radially far outside Compression spring has.

Farther It may be advantageous if the output side plate at least has an attached sheet metal part, which serves as a sealing career for at least a seal can serve.

Dependent z. B. of the design of the variator, the spring cylindrical, waisted or tapered be.

Generally It may be advantageous if the driven-side fixed disk a significantly higher rigidity has as the drive-side fixed disk.

It may be particularly advantageous if the variator is constructed according to the double piston principle, as for example in the DE 103 54 720.7 is described.

to solution The problem may require more than one of the most influenceable ones Parameters to be considered and so z. B. certain properties of the oil with certain mechanical configurations to combine.

• – Viskoses bzw. hydraulisches Medium in Form von Öl,
• – Oberflächenbeschaffenheit der Kontaktbereiche zwischen Kegelscheibe und Umschlingungsmittel,
• – Geometrie zumindest einer Kegelscheibe,
• – Dämpfung zumindest einer Kegelscheibe,
• – Führung zumindest einer Kegelscheibe.

To solve the problem can also contribute a conical-pulley with drive-side and output side cone pulley pairs, each having a fixed disk and a spacer, which are each arranged on a drive-side and an output-side shaft and connectable via a belt connection for torque transmission, wherein at least one of the listed factors in terms the acoustics of the transmission is optimized:

• Viscous or hydraulic medium in the form of oil,
• Surface texture of the contact areas between conical disk and belt,
• Geometry of at least one conical disk,
• Damping of at least one conical disk,
• - Guide at least one cone pulley.

there It may be advantageous if an oil with a Reibgeschwindigkeitsunempfindlichen coefficient of friction Use finds. Furthermore, it may be advantageous, the contact surfaces between To optimize conical disk and belt, z. B. in terms their topography.

From Advantage may still be, at least one stiffness-optimized To provide cone pulley and / or at least a damped conical disk. It may also prove advantageous, at least one radial Outside guided To integrate conical disk into the gearbox.

Farther The invention relates to a method for producing a inventive transmission.

Of Furthermore, the invention relates to a vehicle with a transmission according to the invention.

The Invention will be described below with reference to schematic drawings, for example explained in more detail.

It represent:

1 a partial view of a belt pulley,

2 a substantially the 1 corresponding representation of a further embodiment,

3 and 4 Charts about friction value relationships,

5 and 6 schematic design possibilities of windscreens,

7 schematically the unbalanced dish of a cone pulley,

8a a conical-pulley transmission with geometrically similar conical disk sets,

8b a conical-pulley transmission with stiffness-optimized conical disk sets,

9 and 10 Embodiments of output side cone pulley pairs,

11 and 12 a drive-side conical disk set,

13 an enlarged view of the area XIII in 11 .

14 an output side cone pulley set,

15 a partial view of a driven side cone pulley set.

1 shows only a portion of a conical pulley, namely the driven by a drive motor, such as an internal combustion engine drive or input side of the conical pulley belt drive 1 , In a fully executed conical-pulley transmission, this input-side part is assigned a complementarily designed output-side part of the continuously variable conical-pulley belt transmission, both parts being connected via a belt in the form of a link chain, for example 2 are connected to each other for torque transmission. The conical-pulley transmission 1 has a wave on the input side 3 on, in the illustrated embodiment in one piece with a fixed conical disk or fixed disk 4 is trained. This axially fixed conical disk 4 located in the axial longitudinal direction of the shaft 3 an axially displaceable cone pulley or spacer disc 5 neighboring.

In the presentation after 1 is the link chain 2 on the drive side cone pulley pair 4 . 5 shown in a radially outer position, which results from the fact that the axially displaceable cone pulley 5 is shifted in the drawing in the direction to the right and this displacement movement of the axially displaceable cone pulley 5 to a movement of the link chain 2 leads radially outward, resulting in a ratio change of the transmission in the fast.

The axially displaceable cone pulley 5 can be moved in a conventional manner in the plane of the drawing to the left, in which position the link chain 2 is located in a radially inner position (denoted by the reference numeral 2a is provided), in which a translation of the conical-pulley transmission 1 slow down.

The provided by a drive motor not shown torque is in the in 1 shown drive-side part of the belt pulley belt transmission via a on the shaft 3 stored gear 6 initiated, which on the shaft 3 via a rolling bearing in the form of an axial and radial forces receiving ball bearing 7 is stored, which is on the shaft 3 over a disc 8th and a shaft nut 9 is determined. Between the gear 6 and the axially displaceable cone pulley 5 there is a torque sensor 10 arranged, the one with an axially fixed expanding disc 11 and an axially displaceable expansion disc 12 provided Spreizscheibenkonfiguration 13 assigned. Between the two spreader discs 11 . 12 For example, rolling elements are in the form of the illustrated balls 14 arranged.

One over the gear 6 initiated torque leads to the formation of a rotation angle between the axially fixed expansion disc 11 and the axially displaceable expanding disc 12 , resulting in an axial displacement of the expanding disc 12 leads, and because of this arranged on ramps on which the balls 14 accumulate and so provide an axial displacement of the expansion discs to each other.

The torque sensor 10 has two pressure chambers 15 . 16 of which the first pressure chamber 15 is provided for an application of pressure medium as a function of the introduced torque and the second pressure chamber 16 is supplied with pressure medium, depending on the ratio of the transmission.

For generating the contact force with which the link chain 2 between the axially fixed conical disk 4 and the axially displaceable cone pulley 5 a normal force is applied to a piston / cylinder unit 17 provided the two pressure chambers 18 . 19 has. The first pressure room 18 serves the translation-dependent change of the loading of the link chain 2 and the second pressure chamber 19 serves in conjunction with the torque-dependent controlled pressure chamber 15 of the torque sensor 10 to increase or decrease the contact force with which the link chain 2 between the conical disks 4 . 5 is charged.

The wave 3 has three channels for supplying pressure medium to the pressure chambers 20 , via which pressure medium is fed into the pressure chambers from a pump, not shown. Via an outlet-side channel 21 can the pressure fluid from the shaft 3 drain and recycled the cycle.

The admission of pressure chambers 15 . 16 . 18 . 19 leads to a torque and translation-dependent displacement of the axially displaceable conical disk 5 on the wave 3 , The wave 3 has to accommodate the displaceable cone pulley 5 centering 22 acting as a sliding seat for the displaceable cone pulley 5 serve.

As it is based on the 1 is easily apparent possesses the conical-pulley 1 in the area of the bearing points of the conical disk 5 on the wave 3 in each case a noise damping device 23 , For this purpose, the noise damping device may comprise a ring body and a damping insert or consist only of a damping insert.

In the 1 Reference numerals used also refer to the substantially comparable features of the other figures. The figures are therefore to be regarded as a unity. For the sake of clarity, only the reference numerals are used in the other figures, which over those of 1 go out.

In 2 is now the middle of the three channels 20 in opposite 1 modified form designed. It can be seen that these are the central channel 20 forming hole 24 as a blind hole from the 1 and 2 is made on the right side, is significantly shorter than in 1 , Such blind holes are expensive to manufacture and require a very high degree of accuracy in manufacturing. The production costs and the requirements in terms of process reliability increase overproportional with the length. The shortening of such a hole thus has a favorable z. B. on the manufacturing costs.

In the area of the bottom of this hole 24 branches the cross hole 25 from which several can be arranged distributed around the circumference. In the case shown, this transverse bore 25 shown as a radial bore; However, it can also be manufactured at a different angle than inclined bore. The hole 25 penetrates the lateral surface of the shaft 3 at a location that is independent of the operating state, ie z. B. of the set ratio, in an area that is always on the path plate 5 is covered.

By laying the cross hole 25 in the overlap area of the path plate 5 can the wave 3 be made shorter axially, which space can be saved. Also, by shortening the shaft 3 also result in a load reduction.

The mouth of the channel or the transverse bore 25 can, for example, in the area of the recess 26 , the centering surface 22 the shaft is adjacent to be arranged. This can be particularly advantageous when the teeth 27 that the way-plate 5 axially displaceable but non-rotatable with the shaft 3 connects, for example, is highly stressed by the torque transmission.

In many cases, however, the burden of toothing 27 not the most critical design criterion, leaving the mouth of the hole 25 can be placed in the field of this gearing, as in 2 is shown. Due to the arrangement of the transverse bore 25 in the teeth 27 instead of in the turn 26 , there is an advantage in that there is a larger moment of resistance, whereby the bending stress is reduced in the edge fiber. In addition, the moment of inertia is greater at this point, while the critical fiber through the cross hole 25 is disturbed, remains at about the same radius. This results in a significant reduction of the stresses in the critical area around the mouth of the transverse bore 25 between the teeth of the gearing 27 , The supply of hydraulic fluid is at the 1 and 2 identical, because the pressure chambers 15 and 19 communicate with each other and the path plate 5 connecting bores 28 which has the area of gearing 27 with the pressure room 19 connect. In the figures is the path plate 5 in its extreme left position corresponding to the Anfahrübersetzung or the Underdrive shown. Becomes the path plate 5 Now turn right towards the hard disk 4 shifted, so there is always a part of the cavity or the chamber 29 above the mouth of the transverse bore or the channel 25 so that the required fluid supply as well as in 1 is always guaranteed. As well as in 1 is there for the pressure room 16 two switching states, that of the axial position of the spacer plate 5 depend. In the illustrated position are the control bores 30 exposed so that it is related, with a stopper 31 axially closed channel 20 and the pressure chamber connected to it via a channel, not shown 16 are depressurized or have only ambient pressure. Will now be the path plate 5 on the hard disk 4 To move, it passes over the tax holes 30 , where from a certain way the chamber 29 over the mouths of the tax holes 30 to come to rest. In the chamber 29 However, there is a dependent on the moment high pressure, which then on the tax holes 30 and the channel 20 also in the pressure chamber 16 is brought so that there is also high pressure. In this way, two switching states are realized, which control the contact force translation-dependent.

Furthermore, in 2 a plate spring 32 provided in the unpressurized state of the transmission 1 the path plate 5 brings in a predetermined axial position, whereby a translation of the transmission 1 can be set, which prevents excessive load, for example when towing the vehicle.

The 3 shows two diagrams showing the coefficient of friction over the sliding speed depending on the contact pressure. In this case, the sliding velocity is shown on the abscissa and the coefficient of friction on the ordinate. The dashed line is to be seen as a reference value and represents a friction coefficient, which may be, for example, μ = 0.12. As can be seen from both figures, the coefficient of friction is a function of the sliding speed, which tends to decrease with increasing sliding speed.

As already stated above leads for example at clutches a falling with increasing sliding speed Frictional value to plucking and thus to reduce comfort. It is therefore to strive for this Reibwertabfall over the speed as possible to keep low.

The in 3 Course shown occurs at the contact point between the rocker pressure pieces of the chain and acting together with them contact surfaces of the conical disks. The chain or the belt is loaded both in the direction by the torque to be transmitted, as well as transversely to the direction mainly by the pressing force. This contact force must be chosen so that the torque to be transmitted can be brought with sufficient certainty against slipping on the other pulley set.

The respective distance of the curves in the ordinate direction represents the spread of the coefficient of friction as a function of the contact or Kon Diplomatic squeeze. The lower line stands for low contact pressure and the upper one for a high contact pressure.

At the Comparison of the previous embodiment according to the upper one Diagram and the embodiment of the invention according to the lower diagram you notice that first the scattering range, which limit the two curves, smaller is, which results in a lower dependence of the coefficient of friction of the just applied contact pressure or contact pressure results. Different expressed is the embodiment according to the invention (lower diagram) less sensitive to contact pressure changes.

Next is the 3 it can be seen that the curves in the lower diagram are flatter, with the result that the coefficient of friction dependence on the sliding speed is lower. Due to this flatter negative gradient of the friction coefficient above the sliding speed, a more stable behavior of the friction coefficient is achieved. It is less problematic if the curves move in parallel from top to bottom or vice versa, as if they would change in their inclination, since each change in inclination represents a greater dependence of the coefficient of friction on the sliding speed.

Such a clearly defined coefficient of friction over the sliding speed and over the contact pressure, as in the lower diagram of 3 shown, results in a suppression of the vibration, which is excited by the Reibwertverlauf the steel-steel contact between the belt and chain pulleys and pulleys. By using a corresponding oil with such Reibwertverlauf the vibration can be combated immediately at the place of their formation.

The diagrams in 4 are essentially built like those in 3 , but do not show the dependence on the oil used, but that of the surface characteristics. That in conjunction with 3 in terms of interpretation and improvement This also applies to 4 . d , H. the lower diagram documents a significant improvement in the ratios.

The upper diagram of the 4 shows the conditions on a polished surface, while the lower diagram of the figure represents the coefficient of friction as a function of sliding speed and contact pressure at surface characteristics according to the invention. These surface characteristics are z. B. can be produced by a finishing process, the friction parameters have the right course and keep this over a longer period. For example, noise phenomena occur on smoother surfaces immediately, while at rougher surfaces later, at best, never occur. Such an improvement in noise performance is also achievable by reducing the contact force or contact pressure.

investigations with simulations and measurements showed that the vibration behavior and thus the noise behavior through an increased Tilting rigidity of the axially movable disks or distance disks This is particularly, but not exclusively, with regard to the output side windscreen applies. As a general rule that resulted in an increased Flexural rigidity with which the unfolding of the conical disks, in particular the output side cone pulley set, is reduced in terms of of the noise reduced significant amplitude of vibration. A comparable effect can be increased by an damping be reached at this point.

In the 5 and 6 are now schematically illustrated profiles each of a path plate, in each case only the upper half of the rotationally symmetrical profile is shown.

The 5 shows in the schematic embodiments a) to e) in each case a stiffening of the disc itself 5 and 6 each schematically a part of the driven side, axially movable disk or washer 33 shown, with comparable designs also on the drive side plate 5 can be transmitted.

In the 5a illustrated path plate 33 has in her the belt 2 facing away from several distributed over the circumference arranged stiffening ribs 34 on, which is a pushing away of the radially outwardly projecting part of the disc 33 Reduce under axial load or prevent at best, thereby counteracting a gap of the disc pair.

The path plate 33 according to 5b has a configuration in which the radially outwardly projecting region of the spacer disk 33 is reinforced so that its wall thickness increases radially outward. This is achieved by an appropriate design of the belt 2 reached away from the contour of the disc. The course of this contour, which is shown here continuously, can also be modified such that the wall thickness increases in several stages.

For stiffening the path plate 33 in the axial direction can also radially outside a stiffening collar 35 be appropriate, as in 5c is shown. 5d shows in addition to the radially outer arranged Verstreifungskragen 35 another one stiffening collar 36 , which is arranged radially further inside and thus may optionally also serve as a separation between two pressure chambers.

In the 5c and 5d are the stiffening collars 35 and 36 shown as separate parts or circular rings, with the distance plate 33 to connect. 5e now shows one way, the stiffening collar 35 and / or the stiffening collar 36 integral with the path plate 33 execute, with a production-friendly design can be taken into account in an advantageous manner.

In the 5f and 5g a stiffening of the connection of the disc to the shaft is shown. Here's the hub first 37 the path plate 33 with the radially outwardly projecting part of the path plate 33 over a stiffening ring 38 connected, so that a deformation of this area is at least reduced. Furthermore, again stiffening ribs 34 provided on the one hand with the stiffening ring 38 and on the other hand with the hub 37 the path plate 33 are connected.

In the 6a to 6e are principal damping options for the output side, axially movable disc or spacer 33 shown, but also on the drive side, axially movable disc or washer 5 are applicable.

6a shows first a subdivision of the hub 37 in individual lamellae, this lamella packet is compressed by the contact pressure, which is applied via the hydraulic medium, and thus causes a damping.

In 6b is additionally the stiffening collar 35 designed as a disc pack, which in turn is compressed by the contact pressure. According to 6c can also be the radially inner stiffening collar 36 be designed as a plate pack, said stiffening collar 36 in turn can be used as a separation between different pressure chambers. Alternatively, in one embodiment according to 6c also the hub 37 again be divided into individual slats.

In the 6d and 6e are each springs 39 shown, the additional radial contact pressure increase the friction between the individual disk cylinders, which at the same time the damping effect is increased. Also in 6e it would be possible the hub 37 to execute as a disk set.

In the 6f and 6g another approach is shown, which is to change the direction of tilting of the path plate. In the usual guidance of the travel disc over its radially inner region or via its hub 37 shows the radially outer portion of this spacer plate the largest deflection in the tilt direction. In order to counteract this, it is possible in principle to guide the travel plate on the outside, so that it has radially outer regions on the outer guide 40 is present and therefore can not avoid it. A tilting would then in the radially inner region of the path plate 33 against which measures could be taken as described. However, it should be noted that tilting or distortion of the spacer 33 between the guides is avoided.

In 7 is schematically the output side plate 33 shown, wherein on the drive-side deflection plate 5 comparable effects occur. The respect to the output side plate 33 The statements made thus also apply to the drive-side deflection plate 5 ; For the sake of clarity, the processes and features below are merely based on the path plate 33 described.

The path plate 33 consists of two main areas, namely the cone disc plate 42 and the cone pulley neck or the hub 37 , The path plate 33 is rotationally fixed, but axially displaceable on the output shaft 41 stored and transmits so from the belt 2 introduced torque on the output, so for example via a differential gear and flanged drive shafts, ultimately on the drive wheels of the motor vehicle.

In 7 are out of scale two contours of the path plate 33 represented, namely, the contour A, which represents the undeformed, unloaded state, and on the other hand, the contour B, the representative of the under the action of the force F, deformed state representative. It should be noted that the unloaded, undeformed state according to contour A, as is apparent from the sketch, is rotationally symmetric.

The force F shown by the arrow arranged radially on the outside is the reaction force of the belting means on the sum of the contact forces described above for torque transmission and transmission gear ratio adjustment. At the point of application of the force F shown and along an arcuate segment extending over parts of the circumference of the path plate 33 extends, so lies the belt 2 while on the opposite side (shown below) the wrapping means 2 from the path plate 33 is not touched, because the belt 2 extending toward the complementary pulley set.

As it turned out 7 results, the contour change from contour A to contour B results not only from a deformation of the cone pulley 42 . but also from a tilting of the entire cone pulley 33 , Would only be a deformation of the cone pulley plate 42 occur, contour A and contour B would be virtually identical on the unloaded side shown below.

From the illustration it follows, however, that on the loaded side the deformed contour B is deflected in the direction of the force F acting on it (in the figure to the right), while on the unloaded side in the direction opposite to the force F (in FIG 7 to the left).

This deflection results from the tilting of the entire path plate 33 , because on the one hand the cone pulley neck or the hub 37 also has only a limited rigidity and on the other by the axial displaceability of the conical disk or washer 33 not on their whole, with the wave 41 interacting length can be performed. In addition, for the axial mobility of a certain leadership game between the hub 37 and the wave 41 required, however, on the other hand, a tilting of the spacer 33 promotes. In this case, the tilting is the more pronounced, the greater the game is performed.

Both the deformation and the tilting results from the resulting from the force F, with respect to the respective conical disk rotating bending moment, the (with the same force) with increasing radius on which the belt 2 runs, increases.

Due to this tilting and the uneven deformation of the spacer 33 and the uneven load distribution within the belt 2 becomes the wrapper 2 when passing the loop on the conical disk imposed a radial movement, wherein the chain or the belt means 2 radially inward in the direction of the shaft 41 emotional. Depending on load and deformations, the frictional forces and friction paths that arise here rise sharply. This results in a lower efficiency and increased wear on the interacting surfaces. Furthermore, it has been found that this is an excitation mechanism for frictional vibrations, which in turn can generate noise by structure-borne sound excitations.

In the 8a and 8b is each the variator 43 represented with the drive-side conical disk set 44 and the driven side cone pulley set 45 , where in 8b one opposite a variator 43 according to 8a stiffness-optimized variator 43 is shown.

The drive-side conical disk set 44 each has a fixed disk 4 and a path plate 5 on, via a belt in the form of a link chain 2 with the respective path plate 33 and hard disk 46 the driven-side pulley set 45 are connected.

The in the 8a and 8b used reference numerals 47 to 56 have the following meaning:

47

Input side Wegscheibenhalsdurchmesser

48

output side Wegscheibenhalsdurchmesser

49

drive side Wegscheibentellerbreite

50

drive side Hard disk plate width

51

output side Hard disk plate width

52

output side Wegscheibentellerbreite

53

Length of the drive-side, small sliding seat

54

Length of the drive-side, large sliding seat

55

Length of the output side, large sliding seat

56

Length of the output side, small sliding seat.

In the variator 43 according to 8a are the drive side and output side shroud neck diameter 47 and 48 practically the same design, so have comparable diameter and thus comparable strength. Furthermore, it should be noted that the drive-side and output-side windscreen and Festscheibentellenterbreit 49 . 50 . 51 and 52 about comparable size, so that the geometric design of the respective conical disks 4 . 5 . 33 and 46 and thus their strength is comparable in magnitude. Also the input and output side large and small sliding seats 53 . 54 . 55 and 56 are made comparable in their length, so that in this respect also geometrically comparable conditions prevail, in particular as regards the support of the respective path plate on the shaft connected to it.

Deviating from this is the stiffness-optimized variator 43 according to 8b designed. The output side shroud neck diameter 48 is designed significantly larger than the drive-side end pulley neck diameter 47 , Wherein the output-side spacer disc diameter at the same time as a guide diameter for the pressure spring arranged on it 57 is executed. The compression spring 57 is in 8b cylindrically shown while under 8a can also be tailored. A conical design of the compression spring 57 is also possible.

From the enlarged output side spacer disc diameter 48 results in an increased rigidity of the driven side plate 33 , as a result of this an increased resistance moment against bending is achieved.

Furthermore, it follows from the illustration according to 8b in that the driven-side conical disk set 45 is made significantly stiffer than the drive-side conical disk set 44 , A comparison shows that the output-side fixed disc width 51 is larger than the drive-side fixed disc width 50 , Furthermore, the output-side disk drive width is 52 considerably larger than the drive-side travel disc width 49 , Also, the respective output-side sliding seat length of the large and the small sliding seat 55 and 56 is considerably greater than the length of the corresponding sliding seats of the drive-side pulley set 44 using the reference numbers 53 and 54 are provided.

This results in an increased rigidity of the driven pulley set 45 opposite the drive-side pulley set 44 on the one hand, the strength of the conical disks 33 and 46 , due to their lusher dimensioning. On the other hand results due to the better support on the increased sliding seat lengths 55 and 56 a better protection against tilting under load by the traction means 2 ,

To further increase the tipping rigidity can be the play with which the distance disc 33 on the sliding seats 55 . 56 axially displaceable on the shaft, but rotatably, is stored, minimized, thus also a tendency to tilt the washer 33 counteract.

• – abtriebsseitiger Scheibensatz 45 wird durch die Geometrie der Kegelscheiben 43 und 46 gegenüber dem antriebsseitigen Kegelscheibensatz 44 verstärkt,
• – die Wegscheiben 33 und 5 werden gegenüber den Festscheiben 4 und 46 verstärkt,
• – die Schiebesitzlängen 55 und 56 werden abtriebsseitig gegenüber den antriebsseitigen Schiebesitzlängen 54 und 53 vergrößert,
• – der abtriebsseitige Wegscheibenhaltsdurchmesser 48 wird gegenüber dem antriebsseitigen Wegscheibenhalsdurchmesser 47 vergrößert,
• – Ausgestaltung des abtriebsseitigen großen Schiebesitzes 55 der Wegscheibe 33 so, dass er in Underdrive-Position (bei radial außen laufendem Umschlingungsmittel 2) eine möglichst große Führungslänge aufweist.

In summary, the following designs serve to optimize the stiffness of the variator 43 :

• - driven pulley set 45 is determined by the geometry of the conical disks 43 and 46 opposite the drive-side conical disk set 44 strengthened
• - the path plates 33 and 5 be opposite the hard disks 4 and 46 strengthened
• - the sliding seat lengths 55 and 56 be on the output side with respect to the drive side sliding seat lengths 54 and 53 increased
• - The output-side disk stop diameter 48 is opposite to the drive-side travel disc throat diameter 47 increased
• - Design of the output side large sliding seat 55 the path plate 33 so that it is in the underdrive position (with the belt running radially outwards 2 ) has the largest possible guide length.

In principle, it would be possible, the entire variator 43 to modify accordingly, so with massive conical disks and enlarged sliding seat lengths, etc. to provide, but z. B. set by the available space and the weight of the transmission limits.

9 shows two possible embodiments of the output side cone pulley set 45 , wherein in the lower half of a built-up according to the simple piston principle pulley set is shown, while in the upper half a constructed according to the double piston principle pulley set is shown, as for example in the DE 103 54 720.7 is described.

At the Double piston principle stand for the contact pressure and adjustment of separate pistons available while at Single piston principle only one piston / cylinder unit the corresponding force introduces into the pulley set.

The basic construction of the disc set 45 according to 9 is as previously particularly associated with 8b described. For the design with regard to the strength optimization, the above applies.

Compared to the previously described embodiments has here the compression spring 57 a larger diameter, making their point of attack on the path plate 33 radially further out comes to rest. Among other things, this arrangement provides the advantage that more installation space is available around the cone pulley neck or the hub 37 to thicken or geometrically stronger form and increase in diameter. The resulting strength gain is already described above. When in 9 As shown above, the double piston principle results in a modified arrangement of the compression spring 57 in that it is displaced from the radially inner pressure chamber into the radially outer pressure chamber. That the compression spring 57 radially inside supporting sheet metal part 58 is stuck with the path plate 33 connected and serves with its the spring 57 opposite side as a sealing raceway for the seal 59 , However, this sealing career can also, for example, in connection with 8th shown, in one piece with the path plate 33 be educated. This one-piece with the path plate 33 trained part would then turn with its radially outer region of the compression spring 57 radially inward holders. With internal compression spring 57 This part can form radially inside and outside each a sealing career.

10 shows further possible embodiments of the output side conical disk set 45 , to which in particular with regard to the rigidity optimization, the previously described also to meets. The output side plate 33 is, as previously described, initially on two sliding seats 55 and 56 on the wave 41 supported. Compared with the embodiments shown so far, the centrifugal oil hood 60 significantly strengthened and solidified, so that the distance disc 33 additionally via the sliding seat 62 on the flange part 61 is supported. Should a seal in the area of this sliding seat 62 This may be required by the seal 63 ( 10 above). Thus, the path plate points 33 three sliding seats 55 . 56 and 62 on which it is supported against the shaft. Such a support has a far greater rigidity, so that such a design contributes to solving the problem underlying the invention.

11 schematically shows a drive-side conical disk set 44 with a starting element schematically represented by a dot-dash line 64 , the torque sensor 10 and the belt in the form of the link chain 2 , The radial position of the link chain 2 depends on the size of the wedge gap, the translation dependent between the fixed disk 4 and the path plate 5 is increased or decreased by the fact that the distance disc 5 from the hard disk 4 away or moved axially thereto. In the upper half is that position of the spacer 5 shown, which causes the largest possible translation of the transmission into the slow (underdrive). For this purpose, the distance between the fixed disk 4 and path plate 5 maximum, that is the distance disc 5 is in her in 11 extremely left position. In contrast, in the lower half of the maximum translation in the fast (overdrive) is shown, in between the fixed disk 4 and path plate 5 the distance is minimal, so that the link chain 2 running on the largest possible diameter. This is the pathway 5 shown in their extreme right position.

The path plate 5 is opposite the hard disk 4 rotatably, but added axially movable. This recording takes place on the one hand by the gearing 27 and on the other hand by the two sliding seats 65 and 66 , where the first sliding seat 65 is disposed radially inward, while the second sliding seat 66 in the radially outer region of the path plate 5 radially outside the storage 67 is realized.

A comparison, especially with 8a , shows that by laying the second sliding seat 66 radially outward, as in 11 shown, radially inside and thus save overall axial space. In this space, for example, a part of the housing base 68 be arranged in the channels 20 can be accommodated, for fluid supply, for example, for the translation-dependent setting of the pulley set 44 serve. Another advantage of the arrangement of the second sliding seat 66 radially outward is that the distance disc 5 can be better supported against tilting, whereby the rigidity of the pulley set increases and any resulting disadvantages can be avoided or at least reduced, as already described above.

In 12 is shown schematically as in the area radially within the sliding seat 66 and storage 67 a hydraulic pump indicated by the dot-dash line 69 can be arranged. The hydraulic pump 69 in turn serves to provide the pressurized hydraulic medium for adjusting and pressing the conical disc sets. The hydraulic pump 69 This is done via a drive shaft 69a driven, in turn, in the area of the starting element 64 is driven and coaxial in the shaft 3 of conical disk set 44 can be arranged.

13 shows the detail according to XIII in 11 in an enlarged view. As can be seen from the synopsis of 11 to 13 gives, is the length of the sliding seat 66 due to its arrangement radially outside not space-defining, so that it is possible, despite the large load-bearing length of the sliding seat 66 , the seal 70 the actual sliding seat 66 axially adjacent or in the axial extension of the sliding seat 66 without the length of the sliding seat 66 to shorten decisively. The relatively large length of the sliding seat 66 In turn, for example, has a favorable effect on the rigidity properties of the travel plate and thus of the entire variator. The seal 70 is required because on the one hand the sliding seat 66 must have a certain amount of play to ensure the axial displacement, and on the other on the seal 70 opposite side of the sliding seat 66 a hydraulic pressure prevails, which results from the adjustment and contact pressure of the conical disk, while on the sliding seat 66 opposite side of the seal 70 practically ambient pressure prevails, resulting in a strong pressure gradient results.

In 14 is a driven cone pulley set 45 shown, in turn, a radially inner sliding seat 65 and a second radially outwardly disposed sliding seat 66 having. The second sliding seat 66 is doing so using the centrifugal oil hood 60 formed, on the one hand on the sliding seat 66 supported on the substructure and on the other hand by means of the weld 71 with the output side plate 33 connected is. The in the Fliehölkammer 72 located oil causes a speed-dependent Fliehölkompensation. In the area radially inside the sliding seat 66 by the displacement of the sliding seat 66 radially outward is formed, for example, a transfer case 73 an all-wheel arrangement are housed in 14 is shown schematically by the dashed line. That in the transfer case 73 introduced torque is divided by this on two output shafts, one of which, for example, the front wheels, and the other can drive the rear wheels of the vehicle.

In the 15 illustrated embodiment substantially corresponds to the according 14 , in which case for further speed-dependent Fliehölkompensation in addition to the Fliehölkammer 72 another centrifugal oil chamber 74 is trained.

1

cone pulley

2

link chain

2a

radial inner position of the link chain

3

wave

4

hard disk

5

movable disk

6

gear

7

ball-bearing

8th

disc

9

shaft nut

10

torque sensor

11

axial fixed spreading disc

12

axial movable spreading disc

13

Spreizscheibenkonfiguration

14

roll

15

first pressure chamber

16

second pressure chamber

17

Piston / cylinder unit

18

first pressure chamber

19

second pressure chamber

20

(three) channels (Feed)

21

channel (Outlet side)

22

centering

23

Silencing device

24

(Central) drilling

25

Cross holes)

26

recess

27

gearing

28

connecting bores

29

Cavity / chamber

30

drillings

31

Plug

32

Belleville spring

33

movable disk (Output side)

34

stiffening rib

35

stiffening collar (Outside)

36

stiffening collar (Inside)

37

hub

38

stiffening ring

39

feather

40

external guide

41

wave (Output side)

42

Conical flange plate

43

variator

44

Input side (Cone) pulley set

45

output side (Cone) pulley set

46

hard disk output side

47

Wegscheibenhalsdurchmesser drive side

48

Wegscheibenhalsdurchmesser output side

49

width of the disk drive plate on the drive side

50

width of the fixed disk drive side

51

width of the disk plate on the output side

52

width of the disk plate on the output side

53

Sliding seat length small drive side

54

Sliding seat length large on the drive side

55

Sliding seat length on the large output side

56

Sliding seat length small output side

57

compression spring

58

sheet metal part (Seal face)

59

poetry

60

centrifugal oil cover

61

flange

62

sliding seat

63

poetry

64

starting element

65

first sliding seat

66

second sliding seat

67

storage

68

mounting support

69

hydraulic pump

70

poetry

71

Weld

72

Fliehölkammer

73

Transfer Case

74

(Further) Fliehölkammer

Claims (12)

Conical pulley belt transmission ( 1 ) with drive-side and output-side cone pulley pairs, each having a fixed disk ( 4 . 46 ) and a path plate ( 5 . 33 ), each on a drive-side and a driven-side shaft ( 3 . 41 ) and via a belt ( 2 ) are connectable to the torque transmission, characterized in that a sliding seat ( 65 ) at least one path plate ( 5 . 33 ) in its radially inner region and at least one sliding seat ( 66 ) at least one path plate ( 5 . 33 ) is arranged in its radially outer region. Tapered belt transmission according to claim 1, characterized in that the distance disc ( 5 . 33 ) has two sliding seats. Tapered belt transmission according to claim 1, characterized in that the distance disc ( 5 . 33 ) has three sliding seats. Conical pulley belt transmission according to one of the preceding claims, characterized in that, taking into account the radially outer sliding seat ( 66 ) a centrifugal oil Hood ( 60 ) is formed. Tapered belt transmission according to one of the preceding claims, characterized in that the sliding seat arrangement ( 65 . 66 ) on the drive-side and / or driven-side cone pulley pair ( 44 . 45 ) is provided. Conical pulley belt transmission according to one of the preceding claims, characterized in that the radially outer sliding seat ( 66 ) by an axially adjacent thereto arranged seal ( 70 ) is sealed. Tapered belt transmission according to one of the preceding claims, characterized in that the bearing ( 67 ) of the path plate ( 5 . 33 ) radially within the radially outer sliding seat ( 66 ) is arranged. Conical pulley belt transmission according to one of the preceding claims, characterized in that the radially outer sliding seat ( 66 ) using a component ( 60 ) formed with the spacer ( 5 . 33 ) connected is. Tapered belt transmission according to claim 8, characterized in that the connection is a welded joint ( 71 ). Tapered belt transmission according to one of claims 8 or 9, characterized in that the component ( 60 ) forms a Fliehölhaube. Conical pulley belt transmission according to one of the preceding claims, characterized by two centrifugal oil chambers ( 72 . 74 ). Vehicle, characterized by a gearbox after one of the preceding claims.