DE102021112680A1 - Link chain with a chain width for a belt drive - Google Patents

Abstract

The invention relates to a link chain (1) with a chain width (2) for a belt transmission (3), having at least the following components: - a large number of link plates (4); - a corresponding number of rocker pressure piece pairs (5), each comprising a first Cradle pressure piece (6) and a second cradle pressure piece (7), with a transverse extension in the direction of the chain width (2), with two fixed cradle pressure pieces (6) and two free cradle pressure pieces (7) being provided within each link plate (4), and with one Plate (4) has a radially outer longitudinal bracket (11) and a radially inner longitudinal bracket (12), each extending in the direction of travel of the chain (9), and two end side brackets (13,14) extending in the radial direction (10), with a guide hump (16) is formed on the radially outer longitudinal bracket (11) towards the free rocker pressure pieces (7) in such a way that a guide gap (17) towards the respective free rocker pressure piece (7) is formed. The link chain (1) is primarily characterized in that the guide gap (17) is enlarged at least in the direction of chain travel (9) as a result of a deformation of the link (4) by means of a stretching force (18). Link chain can be achieved and/or a link chain with a lower mass can be used.

Description

• - eine Vielzahl von Laschen;
• - eine korrespondierende Anzahl von Wiegedruckstückpaaren,

umfassend jeweils ein erstes Wiegedruckstück und ein zweites Wiegedruckstück, mit einer Quererstreckung in Richtung der Kettenbreite,
wobei innerhalb jeweils einer Lasche zwei feste Wiegedruckstücke und zwei freie Wiegedruckstücke vorgesehen sind, und
wobei jeweils eine Lasche einen radial-äußeren Längsbügel und einen radial-inneren Längsbügel mit jeweils Erstreckung in Kettenlaufrichtung, sowie zwei endseitige Seitenbügel mit Erstreckung in Radialrichtung aufweist,
wobei von dem radial-äußeren Längsbügel hin zu den freien Wiegedruckstücken ein Führungshöcker derart ausgebildet ist, dass ein Führungsspalt hin zu dem jeweiligen freien Wiegedruckstück gebildet ist. Die Laschenkette ist vor allem dadurch gekennzeichnet, dass der Führungsspalt zumindest in Kettenlaufrichtung infolge einer Verformung der Lasche mittels einer Reckkraft vergrößert ist. Die Erfindung betrifft weiterhin ein Umschlingungsgetriebe für einen Antriebsstrang, einen Antriebsstrang mit einem solchen Umschlingungsgetriebe, sowie ein Kraftfahrzeug mit einem solchen Antriebsstrang.The invention relates to a link chain with a chain width for a belt transmission, having at least the following components:

• - a variety of tabs;
• - a corresponding number of pairs of rocker pressure pieces,

each comprising a first rocker pressure piece and a second rocker pressure piece, with a transverse extension in the direction of the chain width,
two fixed cradle pressure pieces and two free cradle pressure pieces being provided within each tab, and
each plate has a radially outer longitudinal bar and a radially inner longitudinal bar, each extending in the direction of travel of the chain, as well as two end side brackets with an extension in the radial direction,
A guide hump is formed from the radially outer longitudinal bracket towards the free rocker pressure pieces in such a way that a guide gap is formed towards the respective free rocker pressure piece. The plate-link chain is primarily characterized in that the guide gap is enlarged at least in the direction of travel of the chain as a result of a deformation of the plate by means of a stretching force. The invention further relates to a belt transmission for a drive train, a drive train with such a belt transmission, and a motor vehicle with such a drive train.

Plate-link chains are known from the prior art as a belt device for belt-driven transmissions, for example a so-called CVT [engl.: continuous variable transmission], as a traction device. Such a CVT is for example from the DE 100 17 005 A1 known. Such a link chain is set up for the transmission of high torques and high speeds, as are known, for example, from engine construction for motor vehicles. Because the gear noises are unfamiliar and generally perceived as annoying, it is a constant challenge to create a link chain that has the lowest possible noise emissions. At the same time, however, a long service life for the link chain, freedom from replacement as far as possible over the service life of a motor vehicle, and a high level of efficiency are desired. A link chain with cradle pressure pieces is, for example, from the WO 2001/38755 A1 , WO 2013/135 483 A1 and the WO 2016/095913 A1 known. A tab comprises two end side brackets and a radially outer longitudinal bracket and a radially inner longitudinal bracket. Two pairs of cradle pressure pieces are connected to one another with a strap in a manner that transmits tensile force. In relation to a tab, the rocker pressure pieces on the side bracket are referred to as fixed rocker pressure pieces and the mutually adjacent rocker pressure pieces are referred to as free rocker pressure pieces. The free cradle pressure pieces seesaw on the respective fixed cradle pressure piece of the pair of cradle pressure pieces formed, transmitting compressive force, and thus move (freely) to the relevant bracket. Conversely, in a complementary bracket, which is connected via the pair of rocking pressure pieces to the bracket described above, the free rocking pressure piece is the fixed rocking pressure piece, ie the rocking pressure piece on the side bracket side in the complementary bracket.

Good guidance of the free rocker pressure piece is important for high chain strength. The goal is the smallest possible displacement of the rocker pressure pads in a joint. This does not result in any additional asymmetric strap loading, because the rocker contacts are arranged at the same height. In addition, the number of managers should be as small as possible. The executives are additional loads for the strap, which can lead to failure. In addition, so-called chafing points, i.e. guide points, can lead to failure of the link chain and thus the belt transmission due to wear phenomena.

Proceeding from this, the object of the present invention is to at least partially overcome the disadvantages known from the prior art. The features according to the invention result from the independent claims, for which advantageous configurations are shown in the dependent claims. The features of the claims can be combined in any technically meaningful way, whereby the explanations from the following description and features from the figures can also be used for this purpose, which include additional configurations of the invention.

• - eine Vielzahl von Laschen;
• - eine korrespondierende Anzahl von Wiegedruckstückpaaren,

umfassend jeweils ein erstes Wiegedruckstück und ein zweites Wiegedruckstück, mit einer Quererstreckung in Richtung der Kettenbreite,
wobei mittels der Vielzahl der Laschen die Wiegedruckstückpaare im Einsatz zum Übertragen einer Zugkraft zu einem geschlossenen Ring verkettet sind und so eine beidseits weisende Kettenlaufrichtung sowie eine Radialrichtung quer zu der Kettenlaufrichtung und quer zu der Kettenbreite definieren, wobei die Radialrichtung von innerhalb des Rings nach außerhalb des Rings weist, und
wobei jeweils eine Lasche zwei Wiegedruckstückpaare umschließt, sodass in einer Lasche in Kettenlaufrichtung jeweils zwei außenseitige, feste Wiegedruckstücke und zwei innenseitige, freie Wiegedruckstücke vorgesehen sind, und wobei jeweils eine Lasche einen radial-äußeren Längsbügel und einen radial-inneren Längsbügel mit jeweils Erstreckung in Kettenlaufrichtung, sowie zwei endseitige Seitenbügel mit Erstreckung in Radialrichtung aufweist, welche zum Übertragen einer Druckkraft auf das jeweilige feste Wiegedruckstück eingerichtet sind, und wobei von dem radial-äußeren Längsbügel hin zu den freien Wiegedruckstücken ein Führungshöcker derart ausgebildet ist, dass ein Führungsspalt hin zu dem jeweiligen freien Wiegedruckstück gebildet ist.The invention relates to a link chain with a chain width for a belt transmission, having at least the following components:

• - a variety of tabs;
• - a corresponding number of pairs of rocker pressure pieces,

each comprising a first rocker pressure piece and a second rocker pressure piece, with a transverse extension in the direction of the chain width,
the pairs of rocker pressure pieces being linked by means of the large number of brackets to form a closed ring when in use for transmitting a tensile force, and thus defining a chain running direction pointing on both sides and a radial direction transverse to the chain running direction and transverse to the chain width, the radial direction being from inside the ring to outside the ring, and
one plate in each case enclosing two pairs of rocker pressure pieces, so that two outer, fixed rocker pressure pieces and two inner, free rocker pressure pieces are provided in one plate in the direction of travel of the chain, and one plate in each case has a radially outer longitudinal bar and a radially inner longitudinal bar, each extending in the direction of chain travel , as well as two end side brackets extending in the radial direction, which are designed to transmit a compressive force to the respective fixed rocker pressure piece, and wherein a guide hump is formed from the radially outer longitudinal bracket towards the free rocker pressure pieces such that a guide gap towards the respective free cradle pressure piece is formed.

The plate-link chain is primarily characterized in that the guide gap is enlarged at least in the direction of travel of the chain as a result of a deformation of the plate by means of a stretching force.

Unless explicitly stated otherwise, ordinal numbers used in the description above and below only serve to clearly distinguish them and do not reflect any order or ranking of the components referred to. An ordinal number greater than one does not mean that another such component must necessarily be present.

The link chain proposed here is set up as a traction device for a belt transmission, for example for a CVT. In a belt transmission, a link chain forms a wrap-around section on the transmission shafts and two strands in between (together a ring), with one being a tight strand or load strand and the other being a slack strand. The link chain has a chain width and across this chain width a plurality of links are arranged adjacent to each other and form a link group. In use (in a belt drive) the chain width is aligned parallel to the orientation of the at least two transmission shafts. Therefore, the direction of the chain width is also referred to as axial and is constantly aligned in the same way during operation. The extension of the chain is referred to as the direction of travel of the chain, which, as described above, runs in the manner of a ring and changes its orientation during use via the movement of the link chain. The third spatial direction, which is perpendicular to the other two and points outwards from the inside of the closed ring formed, is referred to as the radial direction and changes its orientation together with the direction of travel of the chain. When the direction of chain travel is mentioned, it does not mean a single direction of rotation as in use, but the course of the plates and rocker pressure pieces on both sides in the closed ring, i.e. also the opposite direction to the actual direction of rotation in use.

In the direction of travel of the chain, a number of rocker pressure pieces corresponding to the number of plate groups are provided as rocker pressure piece pairs with a left rocker pressure piece (e.g. front in the direction of circulation) and a right (e.g. rear) rocker pressure piece when viewed from the side (axial top view), with the left rocker pressure piece having a plurality, for example of right lugs is in direct contact, the right rocker lug is in direct contact with a plurality of left lugs, and the two rocker lugs of the pair of rocker lugs are in direct contact with each other. The two rocker pressure pieces of the rocker pressure piece pair transfer the tensile force of the tabs to one another as a compressive force and roll off one another during the movement in a belt transmission, ie describe a rocking movement on one another. To accommodate the majority of the link plates, the rocker pressure pieces have a corresponding width, which generally defines the maximum width of the link chain, ie the chain width. In a CVT, for example, the ends of the rocker pressure pieces are designed obliquely and/or crowned in order to form an approximately parallel contact surface or a clearly defined, narrowly defined contact line or a narrowly defined contact point with the surfaces of the conical disk pairs. In a CVT, a torque is introduced into the plate link chain via the ends of the rocker pressure pads. The rocker pressure pieces are thus loaded on both sides with an axial compressive force. The tabs transmit the torque as a tensile load to the respective associated rocker pressure pieces, for example the immediately adjacent rocker pressure piece, at least on the currently free, i.e. not axially pressed, rocker pressure pieces (at least of the load strand). The cradle pressure pieces or cradle pressure piece pairs are thus linked by means of the multiplicity of straps in a manner that transmits tensile force.

Plates have a pair (radially inside and radially outside) of longitudinal bars, which are also referred to as plate bars, with the main extension or bridging direction in the chain running direction and a pair of side bars with the main extension or bridging direction in the radial direction. The side brackets and longitudinal brackets thus form a frame-shaped component. Most link chains have both long links and short links. In a few applications are only Kurzla mechanical or only long tabs provided. Both the short straps and the long straps each connect two pairs of rocker pressure pieces. In a link chain with both long links and short links, the rocker pressure piece pairs are spaced at different distances from one another in the course of the link chain in the chain direction, namely held at a shorter distance by means of the short links and held by means of the long links at a longer distance in comparison.

As already mentioned at the beginning, good guidance of the free rocker pressure piece is important for high chain strength. For this purpose, a corresponding guide hump is provided on the radially outer longitudinal bracket. A guide gap is formed between the guide hump and the respective free rocker pressure piece, which therefore defines a guide play. Due to the stretching, an unavoidable (plasticizing) cold deformation of the link chain as a result of a tensile load (stretching force) in the direction of chain travel, the link geometry changes. Although the guide gap changes in the prior art, the guide play is only minimally changed by the stretching. This is due to the fact that the constriction of the strap, resulting in a reduction in the guide play, and the pressing of the fixed first rocker pressure piece into the strap, with the result that the guide play is increased, compensate each other. So far, a tab was designed in this way. The constriction means a tab-inward bending or flow of the longitudinal straps, and here relevant the radially outer longitudinal strap, which encompasses the guiding hump. The pressing in of the fixed rocker pressure pieces causes an elongation of the area of the bracket framed by the side brackets, in which the two pairs of rocker pressure pieces are arranged. Both effects have an influence on the elongation of the chain as a result of stretching, i.e. applying a stretching force.

It is now proposed here that when the stretching force is applied, a guide play is increased in comparison to a state after all production steps have been completed. In comparison to the state of the art, the constriction of the tongue or the longitudinal bow is reduced. In one embodiment, a cross section of at least the radially outer longitudinal bracket is enlarged for this purpose. In one embodiment, a different tab material is used or the tab material is treated locally in the area of at least the radially outer longitudinal bow, so that increased stretching strength is achieved. Therefore, when stretching, the pressing of the fixed rocker pressure piece into the strap dominates over the constriction of the (radially outer) longitudinal bar. This increases the guide play of the free rocker pressure piece. The higher the stretching load, the more the guide play increases.

It is further proposed in an advantageous embodiment of the link chain that a contact surface is formed radially outwards between the fixed rocker pressure piece and the link.

In the case of previously known brackets, the aim is for point contact or line contact with an axial extension to be formed between the fixed rocker pressure piece and the bracket. This line contact thus defines the position and orientation of the compressive force resulting from the stretching force. For example, in the prior art, a line contact is formed such that a normal to the tangent on the infinitesimal surface portion of the fixed rocker pad in this line contact is about 8° [eight degrees of 360°]. The radial component of the resulting compressive force is therefore small to negligible.

Here it is now proposed that a flat contact, ie a contact surface, is formed, ie with an extension along the course of the surface of the fixed rocker pressure piece in the cross-sectional plane (spanned by the chain running direction and the radial direction). Thus the radial component of the resulting compressive force is larger than at the radial-inner beginning of the contact surface. Rather, the radial portion is determined in an approximate view as an arc section of a circle from a mean angle between the beginning and the end of the contact area. For example, the mean angle is about 60° [sixty degrees of 360°] from a baseline parallel to the chain running direction in the direction from the fixed rocker pin toward the contacting side bracket and rotating radially-outward toward the radial direction. For example, the start of the contact surface is selected at approximately 45° and the end at approximately 75°. The steeper the resulting mean angle, the less the effect of pinching. The larger the contact area, the lower the surface pressure and thus the probability of failure due to pitting. The end of the contact surface and also the radial portion is at a maximum of 90°.

It is also proposed in an advantageous embodiment of the plate-link chain that the contact surface extends over an angular range of more than 5°, preferably more than 20°, to the direction of travel of the chain.

As already explained above, in the case of previously known brackets, the aim is for line contact to be formed between the fixed rocker pressure piece and the bracket. In contrast to this, it is proposed here that a contact surface is formed which, for example, extends over an angular range of more than 5°. In a preferred off In one embodiment, the contact surface extends over more than 20°, for example over approximately 30°. The larger the contact area, the more precise the forming, even under manufacturing tolerances.

In an advantageous embodiment of the plate-link chain, it is also proposed that a reserve gap extending in the direction of travel of the chain be maintained between the corresponding side bracket and the fixed rocker pressure piece in the area of the central plane of the chain.
wherein the provision gap extends radially outwards to a region of the fixed rocker pressure piece which has a surface normal at an angle of more than 10°, preferably more than 30°, to the direction of travel of the chain.

Here it is proposed that the resulting compressive force on the fixed rocker pressure piece receives an increased radial component than when the fixed rocker pressure piece is attached with a (as previously known) flat line extending in the axial direction. In one embodiment, the fixed rocker pressure piece rests against the strap only in the transition (on the inside of the strap) from the side bracket in question into the longitudinal bracket before the stretching force is applied. This results in a reduction in the constriction of the (radially outer) longitudinal bar when the fixed rocker pressure piece is pressed into the shackle. The transition is an area in which an alignment of the normal on the contact surface of the relevant side bracket to the fixed rocker pressure piece changes from approximately the direction of travel of the chain to an inclined alignment, preferably from more than 10° [ten degrees of 360° with the base line as described above]. , particularly preferably more than 30°, up to an approximately radial alignment, preferably up to a maximum of approximately 75°, of the contact surface of the longitudinal bracket in question to the fixed rocker pressure piece. A mean angle (according to the above definition) of the surface normal or the compressive force resulting from the stretching force between the fixed rocker pressure piece and the transition is formed at about 60° [sixty degrees], for example. The steeper the resulting mean angle, the less the effect of pinching. The transition is, for example, arc-shaped, for example exactly or approximately a circular path. The provision gap is (at least before the stretching), for example, approximately lens-shaped (biconvex) with a center line between the curved outer lines (lens lines) approximately parallel to the extension of the relevant side bracket. After stretching, the holding gap is significantly reduced and the contact area is shifted and/or enlarged. The relationship between the contact area and the radial portion described here is therefore defined for before stretching.

It is also proposed in an advantageous embodiment of the plate-link chain that an average angle of the radially outer compressive force on the fixed rocker pressure piece to the direction of travel of the chain is greater than 10°, preferably greater than 30°, particularly preferably around 60°.

Here it is proposed that the resulting compressive force on the fixed rocker pressure piece receives an increased radial component than when the fixed rocker pressure piece is attached with a (as previously known) flat line extending in the axial direction. The average angle (according to the above definition) of the surface normal or the compressive force resulting from the stretching force between the fixed rocker pressure piece and the strap is more than 10° [ten degrees of 360°], preferably more than 30°, for example about 60° [sixty degrees ]. The steeper the resulting mean angle, the less the effect of pinching. In one embodiment, the mean angle is formed on a line contact between the fixed cradle and the tab, ie the angle of the corresponding tangent (see definition above). A contact surface is preferably formed, for example as suggested above.

It is also proposed in an advantageous embodiment of the link chain that the radially outer longitudinal bracket has such a radial extension that
the reduction in the guide gap in the direction of travel of the chain as a result of a constriction resulting from the stretching force is less than the increase in the guide gap in the direction of travel of the chain as a result of a displacement of the pair of rocker pressure pieces in the direction of travel of the chain resulting from the stretching force.

In this alternative or supplementary embodiment, the deformation of the radially outer longitudinal bracket, ie the (radial) constriction, is reduced in that the radial extent, ie the cross section in its radial extent, is increased compared to previously known solutions. This reduces the elongation of the link chain under a stretching force and thereby the amount of necking. (At least before stretching), the radial extension of the radially outer longitudinal bow is, for example, 1.6 mm [sixteenths of a millimeter] to 2.8 mm, with a distance between the pairs of rocker pressure pieces (based on the contact line of the two rocker pressure pieces, i.e. a division) of 4.5 mm [forty-five tenths of a millimeter] to 8 mm. The numerical values refer to a so-called short strap.

It is further proposed in an advantageous embodiment of the link chain, that the axially outer tabs are identical to the axially inner tabs.

In this particularly advantageous embodiment, it is proposed that not only the outer links, that is to say the axially outermost links in a link pack, be designed according to an embodiment according to the above description. In one embodiment, this is desired so that the outer links are subject to reduced wear.

In the embodiment proposed here, use is made of the fact that when the axially outer link of a link pack is stretched, there is greater guide play than in the axially inner link, because the axially outer link and especially the outer link are subject to higher stretching forces during stretching than the axial experience inner tabs. During operation, the task of guiding is therefore shifted to the axially inner tabs. This reduces the strain on the outer link plates that are relevant to failure as well as the wear and tear caused by the guide. This increases the chain strength.

In one embodiment, different tabs are used axially on the outside (or solely as outer tabs) than axially on the inside, namely axially on the outside according to the embodiment proposed here and axially on the inside with greater constriction behavior, for example in which, as is conventional, the deformation effects of stretching compensate for the guide gap and/or conventional tabs. In this way, the effect of reduced wear on the axially outer straps can be increased without reducing the guidance of the rocker pressure pieces.

• - eine Getriebeeingangswelle mit einem ersten Kegelscheibenpaar;
• - eine Getriebeausgangswelle mit einem zweiten Kegelscheibenpaar; und
• - eine Laschenkette nach einer Ausführungsform gemäß der obigen Beschreibung, mittels welcher das erste Kegelscheibenpaar mit dem zweiten Kegelscheibenpaar Drehmoment-übertragend verbunden ist,

wobei mittels eines regelbaren axialen Abstands der Kegelscheibenpaare eine Übersetzung zwischen der Getriebeeingangswelle und der Getriebeausgangswelle, bevorzugt stufenlos, veränderbar ist.According to a further aspect, a belt transmission for a drive train is proposed, having at least the following components:

• - A transmission input shaft with a first pair of conical pulleys;
• - A transmission output shaft with a second pair of conical pulleys; and
• - a link chain according to an embodiment according to the above description, by means of which the first pair of conical disks is connected to the second pair of conical disks in a torque-transmitting manner,

wherein a transmission ratio between the transmission input shaft and the transmission output shaft can be changed, preferably steplessly, by means of a controllable axial distance between the pairs of conical disks.

The belt transmission is set up for a drive train, for example a motor vehicle, and comprises at least a first pair of conical disks arranged on the transmission input shaft and a second pair of conical disks arranged on the transmission output shaft, as well as a belting means provided for torque transmission between the pairs of conical disks, namely the link chain described above. A pair of conical disks comprises two conical disks which are aligned towards one another with corresponding conical surfaces and can be moved axially relative to one another. The (first) conical disk, also known as a loose disk or displacement disk, can be displaced (axially displaced) along its shaft axis and the (second) conical disk, also known as a fixed disk, is fixed (axially fixed) in the direction of the shaft axis.

During operation of the belt transmission, the link chain is displaced in a radial direction (relative to the respective shaft axis) between an inner position (small effective circle) and an outer position (large effective circle) due to the conical surfaces of the conical disks by means of a relative axial movement of the conical disks of a conical disk pair. The plate-link chain thus runs on a changeable effective circle, i.e. with a changeable running radius. As a result, a different speed transmission and torque transmission from one pair of conical disks to the other pair of conical disks can be set, preferably steplessly.

With the plate-link chain proposed here, a small amount of wear can be achieved axially on the outside without or with little additional effort in terms of the material, that is to say no or a small increase in mass, or even a reduced mass. In this way, a longer service life of the link chain and thus of the belt transmission can be achieved and/or a link chain with a lower mass can be used.

According to a further aspect, a drive train is proposed, having at least one drive machine with a machine shaft, at least one consumer and a belt transmission according to an embodiment according to the above description,
wherein the machine shaft for torque transmission can be connected to the at least one consumer with, preferably steplessly, variable transmission by means of the belt transmission.

The drive train is set up to take a drive provided by a drive machine, for example an internal combustion engine and/or an electric drive machine, and via its machine shaft, for example the combustion engine shaft and/or the (electric) rotor shaft to transmit the given torque for use as required, i.e. taking into account the required speed and the required torque. One use is, for example, an electrical generator to provide electrical energy. In order to transfer the torque in a targeted manner and/or by means of a manual transmission with different gear ratios, the use of the belt transmission described above is particularly advantageous because a large ratio spread can be achieved in a small space and the drive machine can be operated with a small, optimal speed range. Conversely, inertial energy introduced by a drive wheel, for example, can also be absorbed by means of the belt transmission to an electric generator for recuperation, ie the electrical storage of braking energy, with a correspondingly configured torque transmission train. Furthermore, in a preferred embodiment, a plurality of drive machines are provided, which can be operated in series or parallel or decoupled from one another and whose torque can be made available as required by means of a belt transmission according to the above description. An application example is a hybrid drive, comprising an electric drive machine and an internal combustion engine.

With the belt transmission proposed here and the advantageous plate link chain, a small amount of wear can be achieved axially on the outside with little or no additional expense in terms of the material, ie no or a small increase in mass, or even a reduced mass. In this way, a longer service life of the link chain and thus of the belt transmission can be achieved and/or a link chain with a lower mass can be used.

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

Most motor vehicles nowadays have a front-wheel drive and some arrange the drive machine, for example an internal combustion engine and/or an electric drive machine, in front of the driver's cab and transversely to the longitudinal direction of the vehicle. The radial installation space is particularly small in such an arrangement and it is therefore particularly advantageous to use a small-sized belt transmission. The use of a belt transmission in motorized two-wheelers is similar, for which, in comparison to previously known two-wheelers, increased performance is always required with the same installation space. With the hybridization of the powertrains, this problem is getting worse.

This problem is exacerbated in the case of passenger cars in the small car class according to the European classification. The aggregates used in a passenger car in the small car class are not significantly smaller than in passenger cars in larger car classes. Nevertheless, the space available in small cars is much smaller. A comparable problem occurs in hybrid vehicles, in which a number of drive machines and clutches are provided in the drive train, so that the installation space is small overall.

With the drive train proposed here with the advantageous belt drive, a longer service life of the link chain and thus of the belt drive can be achieved and/or a link chain with a lower mass can be used.

Passenger cars are assigned to a vehicle class according to, for example, size, price, weight and performance, with this definition being subject to constant change according to market needs. In the US market, vehicles in the small and micro car classes are assigned to the subcompact car class according to European classification, and in the British market they correspond to the supermini or city car class. Examples of the subcompact 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 hybrid vehicles are the BMW 330e or the Toyota Yaris Hybrid. An Audi A6 50 TFSI e or a BMW X2 xDrive25e, for example, are known as mild hybrids.

• 1: eine Lasche mit einem Führungsspalt in einer Schnittansicht;
• 2: ein Umschlingungsgetriebe mit einer Laschenkette in einer perspektivischen Ansicht; und
• 3: ein Antriebsstrang in einem Kraftfahrzeug mit einem Umschlingungsgetriebe.

The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way restricted by the purely schematic drawings, it being noted that the drawings are not true to scale and are not suitable for defining size relationships. It is presented in

• 1 : a tab with a guide gap in a sectional view;
• 2 : a belt transmission with a link chain in a perspective view; and
• 3 : a drive train in a motor vehicle with a belt transmission.

In 1 a tab 4 with a guide gap 17 is shown in a sectional view. According to the illustration, the radial direction 10 runs from bottom to top, and the axial direction 40 runs perpendicularly to the radial direction 10 into the plane of the image. The direction of travel of the chain 9 runs horizontally perpendicularly to the axial direction 40 and to the radial direction 10 . In the illustration above, a radially outer longitudinal bracket 11 and below a radially inner longitudinal bracket 12 are provided, each with the main extension in the direction of travel 9 of the chain. In the illustration on the left (referred to as front here), a front side bracket 13 is provided and on the right a rear side bracket 14 . A frame is formed by the brackets and two rocker pressure piece pairs 5 are provided within the frame, only the (rear) rocker pressure piece pair 5 being shown here (for the sake of clarity). The free cradle pressure piece 7 is shown on the left and the fixed cradle pressure piece 6 on the right. The fixed rocker pressure piece 6 rests against the rear side bracket 14 and the free rocker pressure piece 7 is guided in this bracket 4 solely by means of a guide hump 16 of the radially outer longitudinal bracket 11 .

Between the fixed rocker pressure piece 6 and the rear side bracket 14 a (purely optional lens-shaped) reserve gap 22 is formed. As a result of the deformation of the tab 4 under the stretching force 18, this is not completely closed. The following applies to the fixed cradle 6 before stretching. It is in radial-outer contact only in the transition 41 between the (rear) side bracket 14 and the radially-outer longitudinal bracket 11 over an angular range 20 of about 30° here. The contact surface 19 (double-dotted dashed line) begins with respect to the base line 42 parallel to the chain running direction 9 and is defined as rotating radially outward (here counterclockwise, in the opposite fixed rocker pressure piece not shown) here at an inner angle 24 from about 45° and ends at an external angle 25 at about 75°. The mean angle 26 and thus the alignment of the (radially outer) compressive force 15 is approximately 60°. This is also the surface normal 23 to the corresponding tangent in this (middle) contact point of the contact surface 19.

In comparison, a conventional position and alignment of a line contact 43 is shown, with the conventional angle 44 being approximately 7° here. Compared to the conventional embodiment, the radial component 45 of the radially outer compressive force 15 is significantly increased. The constriction of at least the radially outer longitudinal bracket 11 is thus reduced. The effect of pressing the fixed rocker pressure piece 6 into the tab 4 dominates and the guide play is increased when stretching.

The tab 4 is shown in an overlay showing the shape of the tab 4 before stretching (solid line) with the shape of the tab 4 after stretching (dashed line). The stretching force 18 is transmitted (roughly) along the chain center plane 21 as a tensile force 8 , which results in a compressive force 15 between the fixed rocker pressure piece 6 and the rear side bracket 14 . Furthermore, the stretching force 18 results in a constriction of at least the radially outer longitudinal bracket 11, which is indicated by the constriction line 46 (exaggerated here for better understanding).

In 2 a belt transmission 3 with a link chain 1 is shown in a perspective view. The link chain 1 is connected in a torque-transmitting manner to a first pair of conical disks 29 and to a second pair of conical disks 30 . The first pair of conical disks 29 is connected to a transmission input shaft 28 and is rotatable about an input-side axis of rotation 47 in a torque-transmitting manner. The second pair of conical disks 30 is connected to a transmission output shaft 31 and is rotatable about an output-side axis of rotation 48 in a torque-transmitting manner. Both pairs of conical pulleys 29,30 each include a fixed pulley and a loose pulley whose spacing 32 can be regulated while maintaining a constant chain length such that the active circles for torque transmission by means of the link chain 1 are enlarged and reduced in opposite directions. The link chain 1 runs during operation (that is to say when the conical disk pairs 29, 30 rotate) along a running direction which corresponds to a direction of the chain running direction 9. The radial direction 10 runs perpendicularly to the chain travel direction 9 from the inside of the link chain 1 to the outside. The axial direction 40 runs perpendicularly to the radial direction 10 and perpendicularly to the direction of travel 9 of the chain. The link chain 1 has a chain width 2 parallel to the axial direction 40, which, by means of the controllable axial distance 32 on the conical disk pairs 29, 30, results in a resulting effective circle on the respective Pulley pairs 29.30 leads. A (stepless) translation by means of the belt transmission 3 of the transmission input shaft 28 and the transmission output shaft 31 is set with an output-side rotation axis 48 .

In 3 a drive train 27 in a motor vehicle 39 with a belt transmission 3 is shown. Motor vehicle 39 has a longitudinal axis 49 and an engine axis 50 , engine axis 50 being arranged in front of driver's cab 51 is. The drive train 27 comprises a first drive machine 33, which is preferably designed as an internal combustion engine 33 and is then connected to the belt transmission 3 in a torque-transmitting manner via an internal combustion engine shaft 35, for example. A second drive machine 34, which is preferably designed as an electric drive machine 34, is also connected via a rotor shaft 36, for example, to the belt drive 3 in a torque-transmitting manner. A torque for the drive train 27 is delivered simultaneously or at different times by means of the drive machines 33, 34 or via their machine shafts 35, 36. However, a torque can also be received, for example by means of the internal combustion engine 33 for engine braking and/or by means of the electric drive machine 34 for the recuperation of braking energy. On the output side, the continuously variable transmission 3 is connected to an output, shown purely schematically, so that a left-hand drive wheel 37 and a right-hand drive wheel 38 can be supplied with torque from the drive machine 33, 34 with variable translation.

With the link chain proposed here, a longer service life of the link chain can be achieved and/or a link chain with a lower mass can be used.

Reference List

1

tab chain

2

chain width

3

belt transmission

4

tab

5

rocker pressure piece pair

6

fixed cradle pressure piece

7

free cradle pressure piece

8th

traction

9

chain direction

10

radial direction

11

radial-outer longitudinal bar

12

radial-inner longitudinal bar

13

front side bar

14

rear side bar

15

radial-outer compressive force

16

guide bump

17

guide gap

18

stretching force

19

contact surface

20

angle range

21

chain center plane

22

lead gap

23

surface normal

24

inner angle

25

outer angle

26

middle angle

27

powertrain

28

transmission input shaft

29

first pair of pulleys

30

second pair of pulleys

31

transmission output shaft

32

Distance of the cone pulleys

33

internal combustion engine

34

electric drive machine

35

combustion shaft

36

rotor shaft

37

left drive wheel

38

right drive wheel

39

motor vehicle

40

axial direction

41

crossing

42

baseline

43

line contact

44

conventional angle

45

radial portion

46

constriction line

47

input-side rotation axis

48

output axis of rotation

49

longitudinal axis

50

motor axis

51

driver's cabin

QUOTES INCLUDED IN DESCRIPTION

This list of the documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 10017005 A1 [0002]
• WO 2001/38755 A1 [0002]
• WO 2013/135483 A1 [0002]
• WO 2016/095913 A1 [0002]

Claims (10)

Plate chain (1) with a chain width (2) for a belt transmission (3), having at least the following components: - a large number of plates (4); - A corresponding number of rocker pressure piece pairs (5), each comprising a first rocker pressure piece (6) and a second rocker pressure piece (7), with a transverse extension in the direction of the chain width (2), with the plurality of brackets (4) being used to connect the rocker pressure piece pairs (5 ) are linked to form a closed ring when used to transmit a tensile force (8) and thus define a chain running direction (9) pointing on both sides and a radial direction (10) transverse to the chain running direction (9) and transverse to the chain width (2), with the The radial direction (10) points from inside the ring to the outside of the ring, and in each case one bracket (4) encloses two pairs of rocker pressure pieces (5), so that in each bracket (4) in the chain running direction (9) there are two outside, fixed rocker pressure pieces (6) and two free cradle pressure pieces (7) on the inside are provided, and each tab (4) has a radially outer longitudinal bracket (11) and a radially inner longitudinal bracket (12) each with a first ckung in chain running direction (9), and two end side brackets (13,14) extending in the radial direction (10), which are designed to transmit a compressive force (15) to the respective fixed rocker pressure piece (6), and wherein from the radial outer longitudinal bracket (11) towards the free rocker pressure pieces (7), a guide hump (16) is designed in such a way that a guide gap (17) towards the respective free rocker pressure piece (7) is formed, characterized in that the guide gap (17) is at least is increased in the chain running direction (9) as a result of a deformation of the plate (4) by means of a stretching force (18). Link chain (1) after claim 1 , A contact surface (19) being formed radially outwards between the fixed rocker pressure piece (6) and the tab (4). Link chain (1) after claim 2 , wherein the contact surface (19) extends over an angular range (20) to the chain running direction (9) of more than 5 °, preferably more than 20 °. Plate-link chain (1) according to one of the preceding claims, wherein between the corresponding side bracket (13,14) and the fixed rocker pressure piece (6) in the area of the chain center plane (21) there is a reserve gap (22) extending in the direction of travel of the chain (9), wherein the reserve gap (22) extends radially outwards to an area of the fixed rocker pressure piece (6) which has a surface normal (23) at an angle (24) of more than 10°, preferably more than 30°, to the direction of travel of the chain ( 9) has. Plate-link chain (1) according to one of the preceding claims, wherein a mean angle (26) of the radially outer compressive force (15) on the fixed rocker pressure piece (6) to the direction of travel (9) of the chain is greater than 10°, preferably greater than 30° , particularly preferably at about 60 °. Link chain (1) according to any one of the preceding claims, wherein the radially outer longitudinal bracket (11) has such a radial extent that the reduction in the guide gap (17) in the chain direction (9) as a result of a constriction resulting from the stretching force (18) is less than the increase in the guide gap (17) in the chain direction (9) as a result of the stretching force (18) resulting in the shifting of the pair of rocker pressure pieces ( 5) in chain direction (9). Plate-link chain (1) according to one of the preceding claims, wherein the axially outer plates (4) are identical to the axially inner plates (4). Continuous transmission (3) for a drive train (27), having at least the following components: - A transmission input shaft (28) with a first pair of conical disks (29); - A transmission output shaft (31) with a second pair of conical pulleys (30); and - a link chain (1) according to one of the preceding claims, by means of which the first pair of conical disks (29) is connected to the second pair of conical disks (30) in a torque-transmitting manner, wherein by means of an adjustable axial distance (32) of Conical disk pairs (29,30) a translation between the transmission input shaft (28) and the transmission output shaft (31), preferably continuously variable, is variable. Drive train (27), having at least one drive machine (33,34) with a machine shaft (35,36), at least one consumer (37,38) and a belt transmission (3). claim 8 , wherein the machine shaft (35,36) can be connected to the at least one consumer (37,38) with a preferably steplessly variable transmission ratio for torque transmission by means of the belt transmission (3). Motor vehicle (39), with at least one driving wheel (37, 38) which is driven by a drive train (27). claim 9 can be driven to propel the motor vehicle (39).

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