Flat chain and tapered belt drive

Abstract

This invention relates to a flat link chain (1) for a tapered belt drive with infinitely adjustable transmission ratio. According to the invention, each link group (30) of the flat link chain has exactly thirty-three chain plates (2) of a predetermined chain plate width (b1) with a width (B), wherein the intermediate link (3-2) places the chain plate (2) at chain plate positions one (KLP1), five (KLP5), eight (KLP8), eleven (KLP11), fourteen (KLP14), seventeen (KLP17), twenty (KLP20), twenty-three (KLP23), twenty-six (KLP26), twenty-nine (KLP29), and thirty-three (KLP33), wherein the first link (3-1) adjacent to the intermediate link (3-2) is at chain plate positions three (KLP3), four (KLP4), nine (KLP9), twelve (KLP3), and thirty-three (KLP33). Chain plates (2) are placed at KLP12, 15, 18, 21, 24, 27, 28 and 32, and the second chain link (3-3) adjacent to the middle chain link (3-2) is placed at chain plate positions (KLP) 2 (KLP2), 6 (KLP6), 7 (KLP7), 10 (KLP10), 13 (KLP13), 16 (KLP16), 19 (KLP19), 22 (KLP22), 25 (KLP25), 30 (KLP30) and 31 (KLP31).

Description

Technical Field

[0001] This invention relates to a flat-ring chain for a tapered belt drive with stepless adjustment of the transmission ratio. The flat-ring chain comprises swaying hinges connecting individual chain links formed by assemblies of multiple chain plates, which are configured as pairs of swaying pressure members pushed into the openings of the chain plates. These swaying pressure members have rolling surfaces that support each other. Here, three chain links arranged adjacent to each other in the circumferential direction of the flat-ring chain form a link group. The flat-ring chain is formed by multiple link groups placed directly adjacent to each other in the circumferential direction, wherein, viewed over the entire width of the flat-ring chain, the chain plates are symmetrically arranged within the link group relative to the midpoint of the link group. This invention also relates to a tapered belt drive for a motor vehicle with stepless adjustment of the transmission ratio. Background Technology

[0002] Flat link chains are used as belt mechanisms in mechanically adjustable continuously variable transmissions (CVTs) of motor vehicles. Mechanically adjustable CVTs can achieve stepless adjustment of the gear ratio without interruption of traction. Flat link chains have chain plates arranged side-by-side connected by a pressure member. In chains currently available on the market, axial locking of the pressure member is achieved via a locking element, such as a short metal wire.

[0003] The following properties characterize flat-ring chains (or CVT flat-ring chains or CVT chains):

[0004] The CVT chain achieves low energy consumption and excellent driving dynamics. This is made possible by the swing-hinged joint structure of the CVT chain, which enables a small circle of rotation on the conical disc, thereby achieving a high transmission shift range.

[0005] High torque can be transmitted using CVT chains. Optionally, thicker catch plates can be used in the outer areas of the line to distribute the load evenly.

[0006] The element is characterized by low internal friction loss caused by the rolling of the rocking pressure element, thereby ensuring good transmission efficiency.

[0007] With its optional earth-shaped end face implemented using a rocking pressure element, the CVT chain is insensitive to track misalignment. Combined with the optional arched conical discs, it reduces the additional component of track misalignment that inevitably occurs during adjustments. Furthermore, the CVT chain is insensitive to disc deformation under load, angular errors, and relative torsion between the fixed and movable conical discs. Therefore, ball guides are not required for the axially movable conical discs.

[0008] When using a CVT chain, a low axial force is achieved at the main sprocket assembly. This allows operation at low hydraulic pressure on a given cylinder surface, another advantage in terms of transmission efficiency.

[0009] The circuit can be implemented as a three-plate assembly, thereby enabling a short basic segmentation. In the short links, only the bow-shaped part of the plate is located between adjacent hinged parts.

[0010] The length of the second slab allows for the calculation and optimization of the division order of the long and short slabs to achieve favorable acoustic performance.

[0011] A flat-ring chain for a continuously variable transmission (CVT) for a motor vehicle is known from EP 2 587 091 B1, wherein the element assembly of the flat-ring chain is composed of three chain elements that follow each other, wherein the arrangement pattern in the corresponding element assembly is the same, and the number of links in the three link units contained in each element assembly is 9, 8 or 8 respectively. Summary of the Invention

[0012] The objective of this invention is to provide a continuously variable transmission (CVT) with a flat-ring chain or a CVT that is further optimized in terms of wear characteristics. Advantageously, this invention should achieve reduced loads on the chain plates and the oscillating pressure components.

[0013] In the flat link chain constructed according to the present invention, the rocking hinge members connected by the links formed by the lap plate group having multiple chain plates are configured as pairs of rocking pressure members pushed into the gaps in the chain plates. The rocking pressure members have rolling surfaces that support each other, wherein three links arranged adjacent to each other in the circumferential direction of the flat link chain form a link group. Here, the flat link chain is formed by multiple link groups placed directly connected in the circumferential direction, wherein, viewed over the entire width of the flat link chain, the chain plates are symmetrically arranged within the link group relative to the midpoint of the link group. According to the present invention, each link group of the flat link chain has a width of exactly thirty-three chain plates, the chain plates having a predetermined chain plate width. Here, the intermediate links occupy the first, fifth, eighth, eleventh, fourteenth, seventeenth, twentieth, twenty-third, twenty-sixth, twenty-ninth, and thirty-third chain plate positions. Furthermore, the first link, directly adjacent to the intermediate link, occupies the chain plate positions of the third, fourth, ninth, twelfth, fifteenth, eighteenth, twenty-first, twenty-fourth, twenty-seventh, twenty-eighth, and thirty-second chain plate positions. Finally, the second link, directly adjacent to the intermediate link (in the other direction), occupies the chain plate positions of the second, sixth, seventh, tenth, thirteenth, sixteenth, nineteenth, twenty-second, twenty-fifth, thirtieth, and thirty-first chain plate positions. This achieves the following advantages: the individual chain plates of the flat link chain of different widths, as well as the oscillating pressure components, experience significantly reduced loads. The lap force can be very evenly distributed through the structure described above, thereby reducing the load on each component and thus achieving an extended service life of the flat link chain under the same load (torque transmission). Alternatively, a flat-ring chain with this modified structure can also transmit higher torque without changing its service life.

[0014] First, the various elements of the claimed inventive subject matter are set forth in the order in which they are presented in the claims or their meaning thereof, and particularly preferred designs of the inventive subject matter are described below.

[0015] Chain plates are a fundamental component of flat link chains. A chain plate is a long, plate-like plate having one or more through openings in its surface for threading and accommodating so-called rocker pressure members (also called pressure members or rocker members).

[0016] The swaying pressure element is also a fundamental component of the flat link chain, besides the chain plate. The swaying pressure element and the through-hole through which the swaying pressure element guides the chain plate together form what is called the swaying hinge. The swaying hinge structure of the flat link chain allows for a small rotational circle on the conical disc, thereby enabling a high gearbox shifting range.

[0017] A component or structural design that prevents the chain plate from migrating axially from the pressure member is called a locking element. In the simplest case, the pressure member is locked at least at its axial end using welded metal wires or the like.

[0018] Other advantageous embodiments of the invention are given in the dependent claims. Features listed individually in the dependent claims can be combined with each other in a technically meaningful manner and can define other embodiments of the invention. Furthermore, the features given in the claims are described and set forth in detail in the specification, wherein other preferred embodiments of the invention are shown.

[0019] According to an advantageous design of the invention, in at least a plurality of directly adjacent link positions directly transverse to the longitudinal extension direction of the chain, within a link of a flat link chain, the link plate for one link position is formed by a unique link plate, such that within the link group, there exists a link plate having a first link plate width and a link plate having a second link plate width different from the first link plate width. The advantage of this design is that the load on the components of the flat link chain, and especially the total frictional loss between the link plates of the flat link chain, is further reduced.

[0020] According to another preferred improvement of the invention, each link group can be formed by eighteen chain plates with a minimum chain plate width, thereby further optimizing the cost of component installation and storage.

[0021] Furthermore, the objective of this invention is achieved by a tapered belt drive device with infinitely adjustable transmission ratio, the tapered belt drive device comprising a first pair of tapered discs disposed on a first shaft and a second pair of tapered discs disposed on a second shaft, and a flat ring chain disposed for transmitting torque between the first pair of tapered discs and the second pair of tapered discs, wherein the flat ring chain is configured according to the invention as described above.

[0022] Advantageously, the conical disks of the first and second conical disk pairs each have the following conical disk angles: the conical disk angles are greater than seven degrees and less than thirteen degrees, particularly between nine and eleven and a half degrees. This achieves a combined effect with the optimization of the flat ring chain constructed according to the invention.

[0023] Furthermore, the tapered disc belt drive can be improved as follows: the tapered discs of the first tapered disc pair and the second tapered disc pair are formed of carburized steel named CrMo or CoNiMo, which also benefits the low wear of the flat ring chain constructed according to the invention and the tapered discs of the drive.

[0024] According to another preferred design of the tapered belt drive, the tapered belt drive together with its tapered disc pair is configured to be driven at a speed of approximately 4000 rpm to 6500 rpm on the drive side and at a speed of approximately 12000 rpm on the driven side, thereby ensuring the following operation: within said operation, wear-reduced operation of the flat ring chain can be achieved.

[0025] Finally, the invention can also be advantageously implemented as follows: the drive conical disc pair is configured to transmit a torque of at least 150 Nm. The conical disc pair is advantageously optimized for a torque range up to a maximum of 460 Nm. Attached Figure Description

[0026] The present invention and its technical field are described in detail below with reference to the accompanying drawings. It should be noted that the invention should not be limited to the embodiments shown. In particular, unless otherwise explicitly stated, it is also possible to extract sub-aspects of the facts set forth in the drawings and combine them with other components and knowledge in this specification and / or the drawings. It should be particularly noted that the drawings and the relationships of size shown are merely illustrative. The same reference numerals denote the same objects, so that supplementary descriptions from other drawings may be used where necessary.

[0027] The attached diagram shows:

[0028] Figure 1 A partial view of a flat-ring chain according to the prior art is shown in a perspective view.

[0029] Figure 2 The upper diagram shows a partial top view of a conventional flat-ring chain, and the lower diagram shows a cross-sectional view of a rocking pressure element along the flat-ring chain, wherein the construction and name of the various elements of the flat-ring chain are discussed based on the schematic diagram.

[0030] Figure 3 The basic structure of the link assembly is illustrated in a top view, with three individual links shown in the upper part of the view and the connection of the three links as a link assembly consisting of the three links shown in the lower part of the view.

[0031] Figure 4 A partial view of the flat-ring chain constructed according to the present invention is shown, and

[0032] Figure 5A schematic diagram illustrates a CVT transmission unit with a tapered belt drive connected to the powertrain of a hybrid vehicle. Detailed Implementation

[0033] Figure 1 A flat link chain 1 for a mechanically adjustable continuously variable transmission (CVT) for a motor vehicle, according to the prior art, is shown. The flat link chain 1 includes a plurality of chain plates 2, a plurality of rocker pressure members 5, and a plurality of locking elements 50, wherein the rocker pressure members 5 for hingedly connecting the chain plates 2 transversely to the longitudinal direction of the flat link chain 1 are provided in the openings 20 of the chain plates 2 to form rocker hinge members 4, and wherein the chain plates 2 are arranged in such a way that they are kept locked via the locking elements 50 to prevent axial migration relative to the rocker pressure members 5.

[0034] Figure 2 The upper diagram shows a partial top view of a conventional flat link chain 1, and the lower diagram shows a cross-sectional view of the rocking pressure member 5 along the rocking hinge 4 of the flat link chain 1. The construction and names of the various elements of the flat link chain 1 should be explained according to the diagrams. In the upper diagram, it is clearly seen how the individual links 3; 3-1, 3-2, 3-3 are arranged sequentially within the flat link chain 1 to form various link groups 30, and how link groups 30 of the same construction are arranged sequentially to form the flat link chain 1.

[0035] In the lower diagram, it can be clearly seen that the chain plates 2 are positioned at corresponding adjacent chain plate positions KLP from the first chain plate position KLP1 to the last chain plate position KLPn, along the width B of the chain plate assembly. Here, the width B of the chain plate assembly approximately corresponds to the internal spacing between the two locking elements 50 at the shown rocker pressure member 5. Similarly, the outer chain width b shown approximately corresponds to the axial length of the rocker pressure member 5—measured along its central axis.

[0036] Figure 3The basic structure of the link group 30 is schematically shown in a top view. Here, three individual links 3; 3-1, 3-2, 3-3 are shown in the upper view, and the connection of the three links 3-1, 3-2, 3-3 is shown in the lower view in the form of the link group 30 formed by the three links 3-1, 3-2, 3-3 as part of the flat ring chain 1. Here, the individual links 3 are connected or joined to each other via a rocking hinge 4 - formed by two pressure members 5 of adjacent links 3 - which passes through an opening 20 in the link plate 2 of the link 3. The flat ring chain 1 consists of a plurality of link groups 30 of the same construction arranged in sequence and connected to each other. It is illustrated in the lower view that the flat ring chain 1 has a plurality of link plates 2 in its width (strap group width) B extending transversely to the longitudinal direction of the flat ring chain 1. Here, each link plate 2 is associated with a link plate position KLP when viewed in the width B of the flat ring chain 1 - shown here by link plate positions from the first link plate position "one" KLP1 (lower edge) to the last link plate position "n" KLPn (upper edge).

[0037] In the region of the axial end of the rocking pressure member 5, the rocking pressure member respectively has a locking element 50, via which the lateral loss of the link plate 2 is prevented.

[0038] Figure 4 A partial top view shows the flat ring chain 1 constructed according to the invention. The shown flat ring chain 1 constitutes a conical pulley belt drive 100 (see Figure 5 ) for a motor vehicle that can infinitely adjust the transmission ratio. Here, the rocking hinge 4 connecting the individual links 3 formed by the strap group having a plurality of link plates 2 is configured as a rocking pressure member 5 that is pushed in pairs into the void 20 of the link plate 2, and the rocking pressure member has rolling surfaces W that support each other ( Figure 1Three links 3 arranged adjacent to each other in the circumferential direction of the flat link chain 1 form a link group 30, wherein the flat link chain 1 is formed by multiple link groups 30 placed directly connected in the circumferential direction, and wherein, viewed over the entire width of the flat link chain 1 or the width B of the plate group, the plate 2 is symmetrically arranged within the link group 30 with respect to the midpoint P of the link group 30. Each link group 3; 3-1, 3-2, 3-3 has exactly thirty-three plate widths B of the predetermined plate width b1, wherein the intermediate link 3-2 of the link group 30 places the predetermined plate width b1 of the plate 2 at the plate positions one KLP1, five KLP5, eight KLP8, eleven KLP11, fourteen KLP14, seventeen KLP17, twenty KLP20, twenty-three KLP23, twenty-six KLP26, twenty-nine KLP29, and thirty-three KLP33. The first link 3-1, directly adjacent to the intermediate link 3-2, has link plates 2 at link plate positions 3KLP3, 4KLP4, 9KLP9, 12KLP12, 15KLP15, 18KLP18, 21KLP21, 24KLP24, 27KLP27, 28KLP28, and 32KLP32. The second link 3-3, directly adjacent to the intermediate link 3-2 (in another direction), has link plates 2 at link plate positions 2KLP2, 6KLP6, 7KLP7, 10KLP10, 13KLP13, 16KLP16, 19KLP19, 22KLP22, 25KLP25, 30KLP30, and 31KLP31. Each link group 3 is formed here by thirty-three link plates 2 of the same link plate width b1.

[0039] Figure 5A CVT transmission unit with a tapered belt drive 100 is schematically illustrated and connected to the powertrain of a hybrid vehicle. The tapered belt drive 100 (also referred to as a gearbox) includes: a first pair of tapered discs 300 having a first tapered disc 301 configured as a fixed disc and a second tapered disc 302 configured as a displacement disc, axially movable; and a second set of tapered discs 500 having a first tapered disc 501 configured as a fixed disc and a second tapered disc 502 configured as a displacement disc, axially movable; and a belt mechanism configured as a flat ring chain 1 connecting the two sets of tapered discs 300; 500. The CVT transmission unit also includes an actuator unit AE, by means of which the displacement discs 302; 502 of the first and second sets of tapered discs 300; 500 can be axially adjusted, allowing a desired gear ratio to be set between the first and second sets of tapered discs 300; 500. The first set of tapered discs 300 can be driven via an electric motor EM and / or an internal combustion engine BKM. Here, between the internal combustion engine BKM and the driven transmission, the electric motor EM is connected to the powertrain via a disengagement clutch located on the internal combustion engine side and a disengagement clutch located on the transmission side. The second conical disc assembly 500 is connected to the drive shaft of the motor vehicle via the transmission unit. The actuator unit AE is controlled via a control unit (not shown).

[0040] Figure 5 Furthermore, it is shown that the conical disks 301 and 302 of the first conical disk pair 300 and the conical disks 501 and 502 of the second conical disk pair 500 have conical disk angles θ1 and θ2, respectively. The conical disk angles are advantageously greater than seven degrees and less than thirteen degrees, and are particularly preferably between nine degrees and eleven and a half degrees.

[0041] This invention is not limited to the embodiments shown in the figures. Therefore, the above description should not be considered limiting but rather explanatory. The following claims should be understood as meaning that the mentioned features exist in at least one embodiment of the invention. This does not exclude the presence of other features. If the claims and the above description define "first" and "second" features, the names are used to distinguish two features of the same type, without specifying a priority order.

[0042] List of reference numerals

[0043] 1. Flat ring chain

[0044] 2 chain plates

[0045] 20. Empty space

[0046] 3 links

[0047] 3-1 First Link

[0048] 3-2 Second Linkage

[0049] 3-3 Third link

[0050] 30-link group

[0051] 4. Swing hinge

[0052] 5. Swinging pressure component

[0053] W rolling surface

[0054] 50 Locking elements

[0055] 100 Conical Belt Drive

[0056] 200 First shaft (conical belt drive)

[0057] 300 First conical disk pair

[0058] 301 First conical disk pair of first conical disks

[0059] 302 The first conical disk paired with the second conical disk

[0060] 400 Second Shaft (Conical Belt Drive)

[0061] 500 Second Conical Disk Pair

[0062] 501 The first conical disk of the second conical disk pair

[0063] 502 The second conical disk of the second conical disk

[0064] KLP chain plate position

[0065] B. Width of the chain plate assembly

[0066] b. Average width of the pressure component

[0067] θ1, θ2 Conical disk angles

[0068] BKM internal combustion engine

[0069] EM motor

[0070] AE actuator unit

[0071] P is the midpoint or symmetric point (used for point symmetry of chain segment groups).

Claims

1. A flat ring chain (1) for a tapered belt drive device with infinitely adjustable transmission ratio, - The rocker hinge (4) of the flat ring chain, which connects the individual links (3) formed by the lap plate assembly having multiple chain plates (2), is configured as a pair of rocker pressure members (5) pushed into the gaps (20) of the chain plates (2), the rocker pressure members having rolling surfaces (W) that support each other. -In which three links (3; 3-1, 3-2, 3-3) arranged adjacent to each other in the circumferential direction of the flat ring chain (1) form a link group (30). -The flat ring chain (1) is formed by multiple chain segment groups (30) placed directly connected in the circumferential direction. -And wherein, viewed over the entire width of the flat link chain (1), the chain plate (2) is arranged symmetrically within the link group (30) relative to the midpoint (P) of the link group (30). Its features are, - Each link group (30) has exactly thirty-three chain plates (2) with a width (B), said chain plates having a predetermined chain plate width (b1). -Among them, the intermediate links (3-2) are placed on the chain plates (2) at chain plate positions (KLP) one (KLP1), five (KLP5), eight (KLP8), eleven (KLP11), fourteen (KLP14), seventeen (KLP17), twentieth (KLP20), twenty-three (KLP23), twenty-six (KLP26), twenty-nine (KLP29) and thirty-three (KLP33). -The first link (3-1) adjacent to the intermediate link (3-2) has a link plate (2) placed at link plate positions (KLP) three (KLP3), four (KLP4), nine (KLP9), twelve (KLP12), fifteen (KLP15), eighteen (KLP18), twenty-one (KLP21), twenty-four (KLP24), twenty-seven (KLP27), twenty-eight (KLP28), and thirty-two (KLP32). -The second link (3-3) adjacent to the intermediate link (3-2) has a link plate (2) placed at link plate positions (KLP) two (KLP2), six (KLP6), seven (KLP7), ten (KLP10), thirteen (KLP13), sixteen (KLP16), nineteen (KLP19), twenty-two (KLP22), twenty-five (KLP25), thirty (KLP30) and thirty-one (KLP31).

2. The flat ring chain (1) according to claim 1, Its features are, In at least a plurality of directly adjacent chain plate positions (KLP), within a link (3, 3-1, 3-2, 3-3) of the flat ring chain (1), the chain plate (2) is formed by a single chain plate (2) having an increased chain plate width (b2).

3. The flat ring chain (1) according to claim 1, Its features are, Each link group (30) is formed by eighteen links (2) with a minimum link width (b1).

4. A tapered belt drive device (100) with infinitely adjustable transmission ratio, the tapered belt drive device comprising a first pair of tapered discs (300) disposed on a first shaft (200) and a second pair of tapered discs (500) disposed on a second shaft (400), and a flat ring chain (1) for transmitting torque between the first pair of tapered discs (300) and the second pair of tapered discs (500), Its features are, The flat ring chain (1) is constructed according to any one of claims 1 to 3 above.

5. The tapered belt drive device (100) according to claim 4, Its features are, The conical disks (301, 302) of the first conical disk pair (300) and the conical disks (501, 502) of the second conical disk pair (500) have the following conical disk angles (θ1, θ2): the conical disk angles are greater than seven degrees and less than thirteen degrees.

6. The tapered belt drive device (100) according to claim 5, characterized in that, The angle of the conical disk is between nine degrees and eleven and a half degrees.

7. The tapered belt drive (100) according to any one of claims 4 to 6, Its features are, The conical disks (301, 302) of the first conical disk pair (300) and the conical disks (501, 502) of the second conical disk pair (500) are formed of carburized steel named 15CrMo5 or 17CoNiMo6.

8. The tapered belt drive device (100) according to any one of claims 4 to 6 above, Its features are, The drive cone pair (300) is configured to be driven at speeds up to a maximum of 12,000 rpm.

9. The tapered belt drive device (100) according to any one of claims 4 to 6, Its features are, The drive cone pair (300) is configured to transmit a torque of at least 150 Nm.

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