Rocker assembly, drive train, transmission, driveline, and vehicle

Abstract

A rocker assembly for coupling links of a drive chain includes a first elongate pin extending between two ends in a longitudinal direction and a second elongate pin extending between two ends in the longitudinal direction. The two ends of the first elongate pin are configured to force-transferringly cooperate with two opposing cones of a pair of pulleys. The first elongate pin has a longitudinal contact surface that, in operation, rolls on opposing longitudinal surfaces of the second elongate pin. The first elongate pin has a longitudinal protrusion positioned at a side of the first elongate pin closest to an inner side of the rocker assembly, and the longitudinal protrusion is configured to engage and guide the second elongate pin.

Description

TECHNICAL FIELD

[0001] The present invention relates to a rocker assembly for coupling links of a transmission chain, to a transmission chain comprising said rocker assembly, to a transmission comprising said transmission chain, including a continuously variable transmission, to a drive train for a mechanical device comprising said transmission, and to a vehicle comprising said transmission. BACKGROUND

[0002] EP 2 034 215 B1 (EP'215) discloses a rocker assembly for coupling links of a transmission chain, wherein each rocker assembly has in operation an inner side at the inboard side of the transmission chain and an outer side at the outboard side of the transmission chain. Each rocker assembly comprises a first elongated pin extending in longitudinal direction between two ends and a second elongated pin extending in longitudinal direction between two ends. The two ends of the first elongated pin are configured to cooperate in force transmitting manner with two opposite cone discs of a pair of pulleys. The first elongated pin has a curved longitudinal contact surface which in operation rolls on an opposite longitudinal surface of the second elongated pin. EP'215 further discloses a transmission chain comprising a plurality of links coupled to each other by said rocker assemblies, wherein each link of the plurality of links comprises a first opening and a second opening through which the rocker assembly extends.

[0003] In the transmission chain disclosed by EP'215 (see Figs. 1-3), the first elongated pin 20 is confined in the first opening 16 of a first link 12 and can oscillate within the contour of the second opening of an adjacent second link 12' through which the rocker assembly 14 extends. The second elongated pin 22 can oscillate within the contour of the first opening 16 of the first link 12 through which the rocker assembly 14 extends and is confined in the second opening of the adjacent second link 12". Of course, the second opening 18 of the first link 12 confines the second pin 22' of a second rocker assembly 14'. The first pin 20' of this second rocker assembly 14' can oscillate within the contour of the second opening 18 of the first link 12. The two contours described above are configured to correspond to the envelope of the path described by the rolling motion of the first and second elongated pins relative to each other. Fig. 3 shows the motion of the second pin 22 of the first rocker assembly 14 in the first opening 16 and of the first pin 20' of the second rocker assembly 14 in the second opening 18. SUMMARY

[0004] A disadvantage of the transmission chain of EP'215 is that the oscillation of the second elongated pin causes friction in the contour thereof in the link during use of the transmission chain. As a result, energy is lost and the friction and accompanying wear eventually lead to damage of the link and thus of its adjacent links and eventually to a rupture of the transmission chain during high loads.

[0005] It is an object of the present invention to provide a transmission chain that alleviates the above-mentioned problems. To this end, the present invention provides a rocker assembly for coupling links of a transmission chain according to claim 1. More particularly, the present invention provides a rocker assembly for coupling links of a transmission chain, wherein the rocker assembly has an inner side at the inboard side of the transmission chain and an outer side at the outboard side of the transmission chain in operation. Each rocker assembly comprises a first elongated pin extending between two ends in a longitudinal direction and a second elongated pin extending between two ends in a longitudinal direction. The two ends of the first elongated pin are configured to cooperate in force transmitting manner with two opposing cones of a pair of pulleys. The first elongated pin has a longitudinal contact surface that rolls over an opposing longitudinal surface of the second elongated pin in operation. When viewed in a cross-sectional plane perpendicular to the longitudinal direction, at least one of the longitudinal contact surface and the opposing longitudinal surface comprises a curved portion. The first elongated pin has a longitudinal protrusion positioned at a side of the first elongated pin closest to the inner side of the rocker assembly, and the longitudinal protrusion is configured to engage and guide the second elongated pin.

[0006] Due to this construction, the force transmitting contact between the pins and the links only occurs via contact surfaces between the links and the pins that are stationary relative to each other. During use, the only contact surfaces that move relative to each other and transmit forces thereon during use are the surfaces of the pins of the rocker assembly. In particular, the force transmitting surfaces that move relative to each other are the longitudinal contact surface of the first elongated pin and the opposing longitudinal surface of the second elongated pin, and the surfaces of the longitudinal protrusion configured to engage and guide the second elongated pin. As a result, the wear of the links through which the rocker assembly extends is minimized, as no friction occurs between the rocker assembly and the links, in view of the contact surfaces between these components not moving relative to each other. This construction also facilitates the transmission of forces from the second elongated pin to the links, and from the links to the first elongated pin, and facilitates the distribution of forces within the links. In view of the above, the risk of chain breakage is reduced.

[0007] The present invention also provides a transmission chain according to claim 12. More particularly, the present invention provides a transmission chain comprising a plurality of links coupled to each other by a rocker assembly according to the present invention. Each link of the plurality of links comprises at least one opening defining a first retaining profile and a second retaining profile, wherein the rocker assembly extends through the at least one opening.

[0008] The effects and advantages of the transmission chain according to the present invention are the same as the effects and advantages of the rocker assembly according to the present invention.

[0009] The present application further provides a transmission comprising the transmission chain according to the present application, a drive train comprising a mechanical device for the transmission according to the present application, and a vehicle comprising the transmission according to the present application. The effects and advantages of the transmission, the drive train and the vehicle according to the present application are the same as those of the transmission chain and the rocker assembly according to the present application.

[0010] The present application will be further clarified by a consideration of the drawings. The embodiments can be applied separately from each other or in combination with each other. BRIEF DESCRIPTION OF DRAWINGS

[0011] Fig. 1 shows a perspective view of a part of a prior art transmission chain.

[0012] Fig. 2 shows a side view of a part of a prior art transmission chain in a straight and a curved configuration.

[0013] Fig. 3 shows a prior art transmission chain link with a first and a second rocker assembly.

[0014] Figure 4 A side view of one example of a rocker assembly according to the present application is shown.

[0015] Figure 5 A part of a chain of a transmission chain link according to the present application is shown, comprising a rocker assembly for cooperating with a pin of a rocker assembly according to the present application, wherein a first pin of a first rocker assembly is in a first opening and a second pin of a second rocker assembly is in a second opening. Figure 4 Figure 4 Figure 4

[0016] Figure 6 A part of a chain of a transmission chain link according to the present application is shown, comprising a rocker assembly in a straight configuration and a curved configuration. Figure 4 Figure 5

[0017] Figure 7 A part of a chain of a transmission chain link according to the present application is shown, comprising a rocker assembly in a straight configuration and a curved configuration. Figure 4 Figure 5

[0018] Figure 8 A side view of another example of a rocker assembly according to the present application is shown.

[0019] Figure 9 A part of a chain of a transmission chain link according to the present application is shown, comprising a rocker assembly for cooperating with a pin of a rocker assembly according to the present application, wherein a first pin of a first rocker assembly is in a first opening and a second pin of a second rocker assembly is in a second opening.

[0020] Figure 10 ​​​​​​​A view of a longitudinal side and end of one example of a second elongated pin according to the present invention is shown.

[0021] Figure 11 Another example of a rocker assembly according to the present invention is shown.

[0022] Figure 12 Another example of a drive chain link according to the present invention is shown, including two openings for cooperating with Figure 11 a rocker assembly of Figure 11 a first pin of a first rocker assembly of Figure 11 a second pin of a second rocker assembly of

[0023] Figure 13 A portion of a chain of a rocker assembly and drive chain link according to the present invention is shown, in a straight configuration, including Figure 11 and Figure 12 a first pin of a first rocker assembly of

[0024] Figure 14 A portion of a chain of a rocker assembly and drive chain link according to the present invention is shown, in a curved configuration, including Figure 11 and Figure 12 a first pin of a first rocker assembly of

[0025] Figure 15 One example of a drive chain link according to the present invention is shown, including a single opening for cooperating with Figure 4 a rocker assembly of Figure 4 a first pin of a first rocker assembly of Figure 4 a second pin of a second rocker assembly of

[0026] Figure 16 One example of a drive chain link according to the present invention is shown, including a single opening for cooperating with Figure 11 a rocker assembly of Figure 11 a first pin of a first rocker assembly of Figure 11 a second pin of a second rocker assembly of

[0027] Figure 17 A cross-sectional view of a transmission according to the present invention is shown, including two pulleys, each pulley including two opposing cones.

[0028] Figure 18 A schematic, partially cross-sectional view of one example of a drive chain between two cones of a pulley according to the present invention is shown.

[0029] Figure 19 A schematic, partially cross-sectional view of another example of a drive chain between two cones of a pulley according to the present invention is shown. DETAILED DESCRIPTION

[0030] In this application, like or corresponding features are denoted by like or corresponding reference signs. The description of the various embodiments is not limited to the examples shown in the drawings and the reference signs used in the detailed description and claims are not intended to limit the description of the embodiments but are included to clarify the embodiments by reference to the examples shown in the drawings.

[0031] Generally, the present invention relates to a rocker assembly 14 for coupling links 12 of a drive chain 10. The rocker assembly 14 has an inner side 38 in an inboard direction side 40 of the drive chain 10 and an outer side 42 in an outboard direction side 44 of the drive chain 10 in operation. The rocker assembly 14 includes a first elongated pin 20 extending in a longitudinal direction between two ends 46, 48 (see Figures 16-18 ) and a second elongated pin 22 extending in a longitudinal direction between two ends. The two ends 46, 48 of the first elongated pin 20 are configured to force transmittingly cooperate with two opposing sheaves 58, 60 of a pair of pulleys 54, 56. Examples of the rocker assembly 10 according to the present invention are shown in Figure 4 , Figure 8 and Figure 11 . These figures are side views of the rocker assembly 14, i.e. viewed in the longitudinal direction of the rocker assembly 14. The first elongated pin 20 has a longitudinal contact surface 21 which in operation rolls on an opposing longitudinal surface 23 of the second elongated pin 22. When viewed in a cross-sectional plane perpendicular to the longitudinal direction, at least one of the longitudinal contact surface 21 and the opposing longitudinal surface 23 comprises a curved portion. The first elongated pin 20 has a longitudinal protrusion 24 positioned at a side 26 of the first elongated pin 20 closest to the inner side 38 of the rocker assembly 14 and the longitudinal protrusion 24 is configured to engage and guide the second elongated pin 22.

[0032] Both the first elongated pin 20 and the second elongated pin 22 preferably have a constant cross-section between their opposing ends 46, 48, 50, 52. Elongated pins 20, 22 with a constant cross-section can be manufactured in long lengths by a rolling process and with high precision and relatively low cost. After the rolling process, the desired length of the elongated pins 20, 22 between their respective ends 46, 48, 50, 52 can be obtained by standard machining operations.

[0033] Further effects and advantages of the rocker assembly 14 have been described in the summary section and are hereby incorporated by reference.

[0034] In an embodiment, examples of which are shown in Figures 4-9As shown in Fig. 1 1, the first elongated pin 20 further comprises a second longitudinal protrusion 34 positioned at a side of the first elongated pin 20 closest to the outer side 42 of the rocker assembly 14 and configured to engage and guide the second elongated pin 22.

[0035] The second longitudinal protrusion 34 has the effect that the second elongated pin 22 engages the first elongated pin 20 at a side closest to the outer side 42 of the rocker assembly 14. The second elongated pin 22 has no moving contact points with the links 12 in the transmission chain 10 and can thus prevent friction and wear resulting therefrom between the second pin 22 and the links 12.

[0036] In an embodiment, the first elongated pin 20 is longer than the second elongated pin 22.

[0037] Due to this configuration, both ends 46, 48 of the first elongated pin 20 can engage with two opposite conical discs 58, 60, while the ends 50, 52 of the second elongated pin 18 do not. This enables the pulleys 54, 56 to transmit force to the transmission chain 10 via the first elongated pin 20 and not via the second elongated pin 22. This also allows the second elongated pin 22 to have a play in its longitudinal direction relative to the first elongated pin 20 when the first elongated pin engages the two opposite conical discs 58, 60 of one of the pulleys 54, 56 in a force transmitting manner.

[0038] In an embodiment, an example of which is shown in Figure 10 As shown in Fig. 1 1, the second elongated pin 22 comprises a groove 68 configured to hold hydraulic fluid to lubricate the rocker assembly 14. The hydraulic fluid can comprise oil.

[0039] The groove 68 enables hydraulic fluid to flow between the longitudinal contact surface 21 and the opposite longitudinal surface 23 and can form a protective film there, which can reduce friction between said surfaces. Furthermore, the hydraulic fluid can also act as a coolant. An example of such a hydraulic fluid is oil.

[0040] In an embodiment, the longitudinal contact surface 21 of the first elongated pin 20 comprises, when viewed in a cross-sectional plane, a curved portion having an involute shape. Additionally or alternatively, the opposite longitudinal surface 23 of the second elongated pin 20 comprises, when viewed in a cross-sectional plane, a curved portion having an involute shape.

[0041] The result of the involute shape is that the curvature of each point along the curved portion is not the same. The involute shape can be chosen such that the curvature is smallest at the edge of the curved portion closest to the inner side 38 of the rocker assembly 14 and largest at the edge of the curved portion closest to the outer side 42 of the rocker assembly 14. This involute shape facilitates the rolling of the longitudinal contact surface 21 over the opposing longitudinal surface 23, thereby reducing the impact noise of the sprocket contact.

[0042] In an embodiment, one of the longitudinal contact surface 21 and the opposing longitudinal surface 23 having the curved portion, when viewed in a cross-sectional plane, also comprises a first flat portion adjacent to the curved portion. The other of the longitudinal contact surface 21 and the opposing longitudinal surface 23, when viewed in a cross-sectional plane, comprises a first opposing flat portion configured to directly oppose the first flat portion. Further, one of the longitudinal contact surface 21 and the opposing longitudinal surface 23 having the curved portion, when viewed in a cross-sectional plane, can comprise a second flat portion adjacent to the curved portion and opposite to the first flat portion. The other of the longitudinal contact surface 21 and the opposing longitudinal surface 23, when viewed in a cross-sectional plane, can comprise a second opposing flat portion configured to directly oppose the second flat portion.

[0043] The first flat portion of the longitudinal contact surface 21 and the first opposing flat portion of the opposing longitudinal surface 23 can be engaged and together act as a stop for the rolling motion of the second elongated pin 22 relative to the first elongated pin 20. The stop creates a first extreme position for the rolling motion of the second elongated pin 22 relative to the first elongated pin 20. Likewise, the second flat portion of the longitudinal contact surface 21 and the second opposing flat portion of the opposing longitudinal surface 23 can be engaged and together act as a stop for the rolling motion of the second elongated pin 22 relative to the first elongated pin 20. The stop creates a second extreme position for the rolling motion of the second elongated pin 22 relative to the first elongated pin 20. The rolling motion of the second elongated pin 22 relative to the first elongated pin 20 is thus limited within the two extreme positions.

[0044] In an embodiment, the end surface of each of the two end portions 50, 52 of the second elongated pin 22 has a spherical, a crown or a straight shape.

[0045] The end surfaces of the two ends 52, 52 can be perpendicular or inclined to the longitudinal direction of the second elongated pin 22. When inclined, they can for example be parallel to the contact surface of the cone disc 58, 60 of one or both of the pulleys 54, 56. Figure 18 Examples of straight shapes parallel to the contact surface of the cone disc 58, 60 are shown in Fig. 5.

[0046] In an embodiment, the end surface of each of the two ends 46, 48 of the first elongated pin 20 has a crown shape.

[0047] The end surface of each of the two ends 46, 48 of the first elongated pin 20 is a surface configured to engage with two opposite cones 58, 60 of a pair of pulleys 54, 56. It is these end surfaces that facilitate the force transmitting manner of cooperation. The crown end surface can be an elliptical crown surface with a first radius of curvature and a second radius of curvature. The first radius of curvature can be in a first direction, which can be parallel to a radial direction of the cones 58, 60 to be engaged. The second radius of curvature can be in a second direction, which can be parallel to a tangent of the cones 58, 60 to be engaged. This crown shape with these two radii of curvature is very suitable to improve the Hertz contact surface between the first elongated pin 20 and the two opposite cones 58, 60 of the pulleys 54, 56 to be engaged.

[0048] The present invention also relates to a transmission chain 10 comprising a plurality of links 12 coupled to each other by rocker assemblies 14 according to the present invention. Each link 12 of the plurality of links 12 comprises at least one opening 16, 18 defining a first retaining profile and a second retaining profile. The rocker assembly 14 extends through the at least one opening 16, 18.

[0049] The transmission chain 10 forms a loop transmission chain 10 which is closed in itself. In operation, the transmission chain 10 will be wrapped around two pulleys 54, 56, transmitting force from a first pulley 54 of the two pulleys 54, 56 to a second pulley 56 of the two pulleys 54, 56. The first pulley 54 forms a prime mover and exerts a force on the ends of one or more first elongated pins 20 which are in contact with the cones 58, 60 of the first pulley 54. These first elongated pins 20 will exert a force on the second elongated pins 22 of their respective rocker assemblies 14, thereby pushing these second elongated pins 22 forward. These second elongated pins 22 exert a force on the second retaining profiles through which they extend, thereby pushing the links 12 forward. Because the links 12 are pushed by the second elongated pins 22, the first retaining profiles push against the first elongated pins 20 extending through said first retaining profiles.

[0050] All links 12 can be equal to each other. However, this is not necessary. For example, the distance from the first retaining profile to the second retaining profile on each link 12 can be different. As a result of the different distances between the first retaining profile and the second retaining profile, the pitch of the rocker assemblies in the transmission chain 10 can also be different. By randomly varying this pitch, the monotonous running frequency of the rocker assemblies 14 in the pulleys 54, 56 can be prevented, resulting in a reduction of impact noise.

[0051] Further effects and advantages of the transmission chain 10 have been described in the summary and are hereby incorporated by reference.

[0052] In an embodiment, examples of which are shown in Figure 5 、 9 and 12, the at least one opening 16, 18 comprises a first opening 16 and a second opening 18. A first retaining profile defines the first opening 16, while a second retaining profile defines the second opening 18. In the alternative, examples of which are shown in Figure 15 and 16 , the at least one opening 16, 18 comprises a single opening defined by a first retaining profile and a second retaining profile.

[0053] The first retaining profile retains the first rocker assembly 14, while the second retaining profile retains the second rocker assembly 14'. The first retaining profile and the second retaining profile do not necessarily extend completely around the rocker assemblies 14, 14' they retain. It is sufficient that they extend only partially around the rocker assemblies 14, 14' to retain them. This means that the middle part of the link 12 between the first opening 16 and the second opening 18 can be omitted without impeding the function of the first retaining profile and the second retaining profile. The at least one opening 16, 18 can thus comprise one or two openings 16, 18.

[0054] In an embodiment, examples of which are shown in Figure 5 、 9 , 12, 15 and 16, the first elongated pin 20 is non-rotatably enclosed by the first retaining profile, such that in operation the first retaining profile prevents the first elongated pin 20 from moving relative to the link 12 in a direction from the inwardly directed side 40 towards the outwardly directed side 44 of the transmission chain 10 and in the longitudinal direction of the transmission chain 10.

[0055] The first retaining profile is located to the left of the single opening 16, 18 or the first opening 16, the first retaining profile forms a form-closed engagement with the first elongated pin 20, preventing movement relative to the link 12. The effect is that the first elongated pin 20 remains in place during operation. This is advantageous for transmitting forces from the link 12 to the first elongated pin 20 and distributing forces within the link 12. Relative movement between the first elongated pin 20, 20' and the first retaining profile of the link 12, 12' is prevented, thereby avoiding associated friction that would otherwise cause wear of the link 12, 12'.

[0056] In an embodiment, examples of which are shown in Figure 5 、 9As shown in 12, 15, and 16, the second elongated pin 22 has a profile complementary to the second retaining profile, such that, in operation, the second retaining profile prevents the second elongated pin 22 from moving relative to the link 12 in the direction from the inward direction side 40 of the drive chain 10 toward the outward direction side 44 and in the longitudinal direction of the drive chain 10. The second elongated pins 22, 22' may include longitudinal cams 28, 28' configured to engage with corresponding grooves 30 in one side of the second retaining profile of the link 12. Alternatively, as in Figure 8 and 9 As shown in the example, the second elongated pins 22, 22' may include longitudinal grooves 70, 70' configured to engage with a corresponding protrusion 72 on one side of the second retaining profile of the link 12.

[0057] Advantageously, such as in Figure 5 and Figure 11 As depicted, longitudinal cams 28, 28' or grooves 70 are arranged on the opposite sides of the second elongated pins 22, 22' relative to the longitudinal surface 23. Similarly, the effect is that the combination of cams 28 and grooves 30, or alternatively, the combination of grooves 70 in the second elongated pin 22 and protrusions 72 on link 12, allows the second elongated pin 22 to be held in place relative to link 12 during operation. This is advantageous for transmitting force from the second elongated pin 22 to link 12 and distributing force within link 12. The second pins 22, 22' are statically confined in the second openings 18, 18' of the links 12, 12', thereby avoiding relative movement and associated friction that would otherwise cause wear on the links 12, 12'.

[0058] As an alternative, the second retaining profile may have a groove 82 on the side adjacent to the outer side 42 of the rocker assembly 14 (see [reference]). Figure 16 The groove is configured to restrict the second elongated pin 22. A similar retaining effect can be achieved in the combination of the longitudinal protrusions 28, 28' on the second elongated pins 22, 22' and the groove 30 on the second retaining profile side of the link 12, and / or the combination of the groove 70 in the second elongated pin 22 and the protrusion 72 on the link 12, that is, allowing the second elongated pins 22, 22' to remain in place relative to the link 12 during operation.

[0059] In one embodiment, a groove 32 is provided on the side 36 adjacent to the outer side 42 of the first retaining profile 14 (see...). Figure 12 The groove is configured to restrict the first elongated pin 20 to form a closed engagement between the link 12 and the first elongated pin 20.

[0060] The effect is that the first elongated pin 20 remains in place during assembly of the chain. Thus, the first elongated pin 20 remains in place even during assembly of the chain, i.e. in the absence of chain tension forces in the longitudinal direction of the drive chain 10.

[0061] In one embodiment, the first elongated pin 20 is prevented from moving in its longitudinal direction through a retaining profile of the chain link 12 through which the first elongated pin 20 extends by means of a transition fit. Alternatively, as shown in the example of Figure 18 the first elongated pin 20 is prevented from moving in its longitudinal direction through a first retaining profile of the chain link 12 through which the first elongated pin 20 extends by means of a clip or a clasp 64 attachable to both end portions 46, 48 of the first elongated pin 20 or, preferably, a retaining extension 66 welded to both end portions 46, 48 of the first elongated pin 20 by spot welding. In Figure 18 an example of this is shown in Fig. 6. Although retaining extensions 66 are drawn on both the upper and lower side of the first elongated pin 21, only one is needed per end portion 46, 48. Furthermore, the longitudinal protrusion 24 can comprise a curved end portion 74, 76 at both ends 46, 48 of the first elongated pin 20, which curved end portions 74, 76 curve towards the outer side 42 of the rocker assembly 14. In Figure 19 an example of this is shown in Fig. 6. The curved end portions 74, 76 can be configured to engage with the end portions 52, 52 of the second elongated pin 22, such that engagement of the end portions 52, 52 of the second elongated pin 22 with the curved end portions 74, 76 can prevent the second elongated pin 22 from moving in its longitudinal direction through a retaining profile through which the second elongated pin 22 extends. The end portions 50, 52 of the second elongated pin 22 can comprise chamfered edges 78, 80 configured to engage with the curved end portions 74, 76. Alternatively, the second elongated pin 22 can be prevented from moving in its longitudinal direction through a second retaining profile of the chain link 12 through which the second elongated pin 22 extends by means of a clip or a clasp 64 attachable to both end portions 50, 52 of the second elongated pin 22 or, preferably, a retaining extension 66 welded to both end portions 50, 52 of the second elongated pin 22 by spot welding.

[0062] If a force applied to the first elongated pin 20 or the second elongated pin 22 tries to induce movement in their respective longitudinal direction, the above described retaining means will prevent such movement. The clip or the circlip 64 or the retaining extension 66 attached to the end portions 46, 48, 50, 52 of the elongated pins 20, 22 can abut against the outer link 12, preventing any further movement of the elongated pins 20, 22. Of course, the clip or the circlip 64 or the retaining extension 66 can be placed such that a small movement or play in the longitudinal direction is allowed. For the second elongated pin 22, the play can be chosen such that, instead of abutting against the placed clip or circlip 64 or retaining extension 66, the travel in the longitudinal direction is limited against one of the cone discs 58, 60 of the pulley 54, 56. The slope of the chamfered end portions 78, 80 can also be chosen such that a small movement or play in the longitudinal direction is allowed. Such play prevents a statically indeterminate structure within the transmission chain 10. Any of the above described retaining means for the first elongated pin 20, 22 can be used in combination with any of the above described retaining means for the second elongated pin 22.

[0063] The present invention further relates to a transmission 62 comprising the transmission chain 10 according to the present invention, to a drive train for a machine comprising the transmission 62 according to the present invention, and to a vehicle comprising the transmission 62 according to the present invention. The transmission 62 can be implemented as a continuously variable transmission (CVT), as shown in Figure 17

[0064] The effects and advantages of the transmission 62, the drive train and the vehicle have been described in the summary section and are hereby incorporated by reference. In summary, the main advantage is that the rocker assembly 14, 14' does not exert a frictional force on the links 12, 12', thereby avoiding wear of the links 12, 12' and reducing the likelihood of breakage of the chain 10.

[0065] The various embodiments described above can be used independently of each other and can be combined with each other in various ways. The reference signs used in the detailed description and in the claims do not limit the description of the embodiments nor the claims. The reference signs are only used to clarify.

[0066] Legend

[0067] 10 - transmission chain

[0068] 12 - link

[0069] 14 - rocker assembly

[0070] 16 - first opening

[0071] 18 - second opening

[0072] 20 - first elongated pin

[0073] ​21 - longitudinal contact surface

[0074] 22 - second elongated pin

[0075] 23 - opposite longitudinal surface

[0076] 24 - longitudinal protrusion

[0077] 26 - side of first elongated pin closest to inner side of rocker assembly

[0078] 28 - longitudinal cam of second elongated pin

[0079] 30 - recess in one side of second retaining profile 32 - recess in one side of first retaining profile adjacent outer side of rocker assembly 34 - second longitudinal protrusion

[0080] 36 - side of first retaining profile adjacent outer side of rocker assembly

[0081] 38 - inner side (of rocker assembly)

[0082] 40 - side of transmission chain in inward direction

[0083] 42 - outer side (of rocker assembly)

[0084] 44 - side of transmission chain in outward direction

[0085] 46 - first end of first elongated pin

[0086] 48 - second end of first elongated pin

[0087] 50 - first end of second elongated pin

[0088] 52 - second end of second elongated pin

[0089] 54 - pulley

[0090] 56 - pulley

[0091] 58 - cone of pulley

[0092] 60 - cone of pulley

[0093] 62 - transmission

[0094] 64 - clip or circlip 64

[0095] 66 - retaining extension

[0096] 68 - groove

[0097] 70 - longitudinal recess (in the second elongated pin) 72 - corresponding protrusion 74 - curved end portion (of the longitudinal protrusion). 76 - curved end portion (of the longitudinal protrusion). 78 - chamfered end portion (of the second elongated pin) 80 - chamfered end portion (of the second elongated pin) 82 - recess in one side (of the second retention profile)

Claims

1. A rocker assembly (14) for coupling a link (12) of a drive chain (10), wherein the rocker assembly (14) has an inboard side (38) and an outboard side (42) in operation, the inboard side (38) being on an inboard direction side (40) of the drive chain (10), the outboard side (42) being on an outboard direction side (44) of the drive chain (10), wherein, The rocker assembly (14) comprises: a first elongated pin (20) extending in a longitudinal direction between two first pin ends (46, 48); and a second elongated pin (22) extending in a longitudinal direction between two second pin ends (50, 52), wherein the two first pin ends (46, 48) of the first elongated pin (20) are configured to force-transmitingly cooperate with two opposing sheaves (58, 60) of a pair of pulleys (54, 56), wherein the first elongated pin (20) has a longitudinal contact surface (21) that, in operation, rolls on an opposing longitudinal surface (23) of the second elongated pin (22), wherein at least one of the longitudinal contact surface (21) and the opposing longitudinal surface (23) comprises a curved portion when viewed in a cross-sectional plane perpendicular to the longitudinal direction, wherein the first elongated pin (20) has a longitudinal protrusion (24) positioned at a side (26) of the first elongated pin (20) closest to an inner side (38) of the rocker assembly (14) and configured to engage and guide the second elongated pin (22), and wherein the first elongated pin (20) is longer than the second elongated pin (22).

2. The rocker assembly of claim 1, wherein, The first elongated pin (20) further comprises a second longitudinal protrusion (34) positioned at a side of the first elongated pin closest to an outer side (42) of the rocker assembly and configured to engage and guide the second elongated pin (22).

3. The rocker assembly of claim 1 or 2, wherein, The second elongated pin (22) comprises a groove (68) configured to hold hydraulic fluid to lubricate the rocker assembly (14).

4. The rocker assembly of claim 3, wherein, The hydraulic fluid comprises oil.

5. The rocker assembly of claim 1 or 2, wherein, The longitudinal contact surface (21) of the first elongated pin (20) comprises a curved portion having an involute shape when viewed in the cross-sectional plane.

6. The rocker assembly of claim 1 or 2, wherein, The opposing longitudinal surface (23) of the second elongated pin (22) comprises a curved portion having an involute shape when viewed in the cross-sectional plane.

7. The rocker assembly of claim 1 or 2, wherein, One of the longitudinal contact surface (21) and the opposing longitudinal surface (23) having a curved portion further comprises a first flat portion adjacent to the curved portion when viewed in the cross-sectional plane, and wherein the other of the longitudinal contact surface (21) and the opposing longitudinal surface (23) comprises a first opposing flat portion configured to be directly opposite to the first flat portion when viewed in the cross-sectional plane.

8. The rocker assembly of claim 7, wherein, The longitudinal contact surface (21) having a curved portion and one of the opposing longitudinal surfaces (23) comprise, when viewed in the cross-sectional plane, a second flat portion adjacent to the curved portion and opposite to the first flat portion, and wherein the other of the longitudinal contact surface (21) and the opposing longitudinal surface (23) comprise, when viewed in the cross-sectional plane, a second opposing flat portion configured to be directly opposite to the second flat portion.

9. The rocker assembly of claim 1 or 2, wherein, The distal end surface of each of the two second pin ends (50, 52) of the second elongated pin (22) has a spherical, a crowned or a straight line shape.

10. The rocker assembly of claim 1 or 2, wherein, The distal end surface of each of the two first pin ends (46, 48) of the first elongated pin (20) has a spherical, a crowned or a straight line shape.

11. A drive chain (10) comprising a plurality of chain links (12) coupled to each other by a rocker assembly (14) according to any of the preceding claims, wherein each chain link (12) of the plurality of chain links (12) comprises at least one opening (16, 18) defining a first retention profile and a second retention profile, wherein the rocker assembly (14) extends through the at least one opening (16, 18).

12. The transmission chain of claim 11, wherein, The at least one opening (16, 18) comprises a first opening (16) and a second opening (18), wherein the first retention profile line delimits the first opening (16) and the second retention profile line delimits the second opening (18).

13. The drive chain as claimed in claim 11, characterized in that The at least one opening (16, 18) comprises a single opening, which is delimited by the first retention profile and the second retention profile.

14. A transmission chain according to any one of claims 11-13, characterized in that The first elongated pin (20) is irrotatably enclosed by the first retention profile, such that in operation the first retention profile prevents the first elongated pin (20) from moving relative to the chain link (12) in a direction from an inboard direction side (40) of the drive chain (10) towards an outboard direction side (44) and in a longitudinal direction of the drive chain (10).

15. A transmission chain according to any one of claims 11-13, characterized in that The second elongated pin (22) has a profile complementary to the second retention profile, such that in operation the second retention profile prevents the second elongated pin (22) from moving relative to the chain link (12) in a direction from an inboard direction side (40) of the drive chain (10) towards an outboard direction side (44) and in a longitudinal direction of the drive chain (10).

16. The transmission chain of claim 15, wherein, The second elongated pin (22) comprises a longitudinal cam (28) configured to engage with a corresponding cam groove (30) in one side of the second retention profile of the chain link (12).

17. The drive chain as claimed in claim 15, wherein, The second elongated pin (22) comprises a longitudinal groove (70) configured to engage with a corresponding protrusion (72) in one side of the second retention profile of the chain link (12).

18. The drive chain as claimed in claim 15, wherein, The second holding contour is provided with a second pin groove (82) on a side adjacent to an outer side (42) of the rocker assembly (14), the second pin groove (82) being configured to restrict the second elongated pin (22).

19. The transmission chain according to any one of claims 11-13, characterized in that, The first holding contour is provided with a first pin groove (32) on a side (36) adjacent to an outer side (42) of the rocker assembly (14), the first pin groove (32) being configured to restrict the first elongated pin (20) to form a form-closed engagement between the link (12) and the first elongated pin (20).

20. The transmission chain according to any one of claims 11-13, characterized in that, The first elongated pin (20) extending through the holding contour is prevented from moving in its longitudinal direction through the holding contour of the link (12) by means of a transition fit.

21. The transmission chain according to any one of claims 11-13, characterized in that, The first elongated pin (20) extending through the first holding contour of the link (12) is prevented from moving in its longitudinal direction through the first holding contour by means of a clip or a circlip (64) attachable to both first pin ends (46, 48) of the first elongated pin (20) or a retaining extension (66) welded to both first pin ends (46, 48) of the first elongated pin (20).

22. The transmission chain according to any one of claims 11-13, characterized in that, The longitudinal protrusion (24) comprises curved end portions (74, 76) at the first pin ends (46, 48) of the first elongated pin (20), the curved end portions (74, 76) being curved towards the outer side (42) of the rocker assembly (14), and wherein the curved end portions (74, 76) are configured to engage with second pin ends (50, 52) of the second elongated pin (22) such that the engagement of the second pin ends (50, 52) of the second elongated pin (22) with the curved end portions (74, 76) prevents the second elongated pin (22) extending through the holding contour from moving in its longitudinal direction through the holding contour.

23. The chain as set forth in claim 22, wherein, The two second pin ends (50, 52) of the second elongated pin (22) comprise chamfered edges (78, 80) configured to engage with the curved end portions (74, 76).

24. The transmission chain according to any one of claims 11-13, characterized in that, The second elongated pin (22) extending through the second holding contour of the link (12) is prevented from moving in its longitudinal direction through the second holding contour by means of a clip or a circlip (64) connectable to both second pin ends (50, 52) of the second elongated pin (22) or a retaining extension (66) welded to both second pin ends (50, 52) of the second elongated pin (22).

25. A transmission (62) comprising a transmission chain (10) according to any one of claims 11-24.

26. The transmission (62) of claim 25, characterized by The transmission is implemented as a continuously variable transmission.

27. A drive train of a mechanical device comprising a transmission (62) according to claim 25 or 26.

28. A vehicle comprising a transmission (62) according to claim 25 or 26. The second holding contour is provided with a second pin groove (82) on a side adjacent to an outer side (42) of the rocker assembly (14), the second pin groove (82) being configured to restrict the second elongated pin (22). The first holding contour is provided with a first pin groove (32) on a side (36) adjacent to an outer side (42) of the rocker assembly (14), the first pin groove (32) being configured to restrict the first elongated pin (20) to form a form-closed engagement between the link (12) and the first elongated pin (20). The first elongated pin (20) extending through the holding contour is prevented from moving in its longitudinal direction through the holding contour of the link (12) by means of a transition fit. The first elongated pin (20) extending through the first holding contour of the link (12) is prevented from moving in its longitudinal direction through the first holding contour by means of a clip or a circlip (64) attachable to both first pin ends (46, 48) of the first elongated pin (20) or a retaining extension (66) welded to both first pin ends (46, 48) of the first elongated pin (20). The longitudinal protrusion (24) comprises curved end portions (74, 76) at the first pin ends (46, 48) of the first elongated pin (20), the curved end portions (74, 76) being curved towards the outer side (42) of the rocker assembly (14), and wherein the curved end portions (74, 76) are configured to engage with second pin ends (50, 52) of the second elongated pin (22) such that the engagement of the second pin ends (50, 52) of the second elongated pin (22) with the curved end portions (74, 76) prevents the second elongated pin (22) extending through the holding contour from moving in its longitudinal direction through the holding contour. The two second pin ends (50, 52) of the second elongated pin (22) comprise chamfered edges (78, 80) configured to engage with the curved end portions (74, 76). The second elongated pin (22) extending through the second holding contour of the link (12) is prevented from moving in its longitudinal direction through the second holding contour by means of a clip or a circlip (64) connectable to both second pin ends (50, 52) of the second elongated pin (22) or a retaining extension (66) welded to both second pin ends (50, 52) of the second elongated pin (22).

25. A transmission (62) comprising a transmission chain (10) according to any one of claims 11-24. The transmission is implemented as a continuously variable transmission.

27. A drive train of a mechanical device comprising a transmission (62) according to claim 25 or 26.

28. A vehicle comprising a transmission (62) according to claim 25 or 26.

Images