JP5921713B2 - Drive belt for a continuously variable transmission having a transverse member with a contact area - Google Patents

Description

  The present invention relates to a drive belt for a continuously variable transmission having two pulleys. Each pulley comprises two pulley sheaves, the pulley sheaves having at least partly conical surfaces for sandwiching the drive belt. A known drive belt has an endless carrier. The endless carrier includes a pair of flexible metal rings stacked and a plurality of transverse members. These transverse members form a substantially continuous row along the circumference of the endless carrier, each transverse member being recessed to open towards the axial side or side of the drive belt Part is defined. An endless carrier is disposed in the recessed portion. Such a drive belt with a generally C-shaped transverse member is known, for example, from EP-A-0014013, in particular from FIG.

  The known transverse member comprises a base portion located radially inward or below the recessed portion, a connecting portion located on the closed axial side of the recessed portion, and a radially outward portion of the recessed portion. Or a top portion located above. A so-called tilted edge is provided in the base portion on the main surface in front of the transverse member. The tilting edge forms a transition between the radially outward section or head section of the transverse member and the tapered or tapered radially inward section or bottom section. Such tapered bottom sections and tilting edges allow adjacent lateral members in the drive belt to tilt with respect to each other on the curved track portion of the transmission drive belt.

  Furthermore, the main surface of the transverse member is provided with a protrusion. This protrusion is inserted into a hole provided in the opposing major surface of the adjacent transverse member in the drive belt. Thus, such protrusions and holes serve to align the plurality of transverse members with each other in the row of transverse members.

  In addition, on both axial sides of the base portion, the transverse member is provided with a pulley contact surface for contact with a pulley sheave surface for forming frictional contact with the pulley.

  During operation of the drive belt in the transmission, the transverse members press against each other from the driven pulley of the transmission toward the drive pulley along the circumference of the endless carrier. Thereby, the front major surface of each subsequent transverse member contacts the rear major surface of each preceding transverse member, and exerts a pressing force on such preceding transverse member during travel. In known transverse members, the entire head section is responsible for such pressing contact. During such operation, vibration is generated in the drive belt, that is, in the track portion of the drive belt extending from the drive pulley to the driven pulley. This vibration is disadvantageous because it creates noise and / or mechanical stress.

  According to the present invention, vibrations can be advantageously reduced by providing precisely defined contact between the transverse members in the track portion of the drive belt. In particular, according to the invention, the contact between the transverse members is realized by at least two contact areas. These contact areas are part of the main surface of the transverse member. In addition, one such contact area is disposed radially outward from the tilted edge at the base portion of each lateral member, and the second contact area is at the top portion of each lateral member. It is arranged in the vicinity of the upper part of the transverse member. As an alternative according to the invention, the radial separation of the two contact areas should be maximized at least within the constraints determined by the geometry of the transverse member and the manufacturing process.

  The contact area according to the invention protrudes relative to another part of the relevant main surface (i.e. the part surrounding the contact area). Thus, in these contact areas, the thickness of the transverse member is greater than at the location of another part of the associated major surface. However, such a large thickness is small in absolute value, typically as small as 5-10 and as large as about 100 micrometers. Furthermore, for reasons of well-known drive belt designs, particularly as described in EP-A-1061285, the thickness in the contact area at the top portion of the transverse member is preferably that of the transverse member. Somewhat greater than the thickness in the contact area located in the base portion.

  In a detailed aspect of the invention, the surface area of the contact region at the top portion of the transverse member is the same as the surface area of the contact region at the base portion of the transverse member or the surface area of the contact region at the base portion of the transverse member. Bigger than.

  In a detailed aspect of the invention, the two contact areas each extend to the axial side of the transverse member.

  In a more detailed aspect of the invention, the contact area located in the base part of the transverse member is composed of two parts. Each such contact area portion is arranged with respect to each axial side of the transverse member. In particular, these two contact area portions of the base portion are separated from each other at an axial position that coincides with the axial position on the closed side of the recess. In particular, the protrusions and holes are provided in the base part between these two contact area parts. Preferably, the radial position of the protrusion at least partially overlaps the radial position of the tilting edge. Therefore, the tilting edge is partially interrupted by the protrusion.

  Preferably, one of the contact area portions provided in the base portion is disposed below the recessed portion and extends over most or all of the axially extending length of the recessed portion. Yes.

  In a more detailed aspect of the invention, the contact area located at the top part of the transverse member is also composed of two parts. Each such contact region portion is also arranged with respect to each axial side portion of the transverse member.

  All the above detailed descriptions of the technical means related to the invention contribute directly or indirectly to the drive belt to improve the stability in the track portion of the drive belt.

  The present invention is based on the technical insight that without the above-mentioned defined contact areas, each located at a high point, i.e. protruding areas, occur irregularly in each transverse member of the drive belt. As a result, the (initial) contact points between the lateral members change irregularly along the circumference of the drive belt, and the above-described harmful vibration is likely to occur. However, the use of the means according to the invention ensures that the contact between the transverse members is essentially uniform across the drive belt in a relatively simple and reliable manner.

  The present invention will be described in detail below with reference to the accompanying drawings.

It is a perspective view which cuts off and shows the transmission which has a pulley and a drive belt partially. FIG. 4 is a front view of a generally C-shaped transverse member of the drive belt, showing the front profile of the transverse member. FIG. 3 is a side view of the transverse member shown in FIG. 2. FIG. 3 shows the known transverse member shown in FIG. 2 assembled to a drive belt. 1 shows a first embodiment of a generally C-shaped transverse member according to the present invention. FIG. FIG. 6 shows a second embodiment of a generally C-shaped transverse member according to the present invention. FIG. 6 shows a third embodiment of a generally C-shaped transverse member according to the present invention.

  FIG. 1 schematically shows a central portion of a continuously variable transmission used, for example, in a drive unit of a passenger car. This transmission is known per se and has at least first and second drive wheels or pulleys 1, 2 and a drive belt 3. The drive belt 3 is accommodated between the conical sheaves 4 and 5 of the pulleys 1 and 2. At least one sheave 4 of each pulley 1, 2 is movable in the axial direction along each pulley shaft 6, 7. For this purpose, electronically controllable and hydraulically acting movement means are generally accommodated in the transmission. The movement means are not shown. The operation of this movement means results in an axial movement of the movable sheave 4 and thus an adjustment of the radial position R of the drive belt 3 between the sheaves 4, 5 of the pulleys 1, 2. The driving force of the pulleys 1 and 2 is transmitted by friction at the contact between the pulley sheaves 4 and 5 and the driving belt 3.

  The known drive belt 3 is composed of an endless carrier 31 and a plurality of transverse members 32. The plurality of lateral members 32 are assembled to the carrier 31 in a substantially continuous row along the circumference of the carrier 31. The transverse member 32 is supported by the drive belt 3 so as to be freely movable along the circumference of the drive belt 3.

  FIG. 2 is an enlarged view of the transverse member 32 as seen in the circumferential direction L of the drive belt 3, and FIG. 3 is a side view of the transverse member 32 as seen from the right side to the left side in FIG.

  The known transverse member 32 is formed in a shape similar to the Roman letter “C”, ie, generally C-shaped. The known transverse member 32 has a recessed portion 33 disposed at the center. The recessed portion 33 is open toward one axial side portion of the lateral member 32. Thus, the known transverse member 32 has three main parts 34, 35, 36. The first portion or the base portion 34 of these main portions is located below or inward of the recessed portion 33 when viewed in the radial direction R. The second portion or the connecting portion 35 of the main portion is located side by side with the recessed portion 33 when viewed in the axial direction A. The third portion or the top portion 36 of the main portion is located radially outward of the recessed portion 33. In the drive belt 3, an endless carrier 31 is disposed in the recessed portion 33.

  At both ends in the axial direction of the base portion 34, pulley contact surfaces 37 for forming frictional contact with the pulley sheaves 4, 5 are provided. These pulley contact surfaces 37 of the transverse member 32 are oriented at a predetermined angle φ with respect to each other, this angle φ being defined between the conical sheaves 4, 5 of the pulleys 1, 2. Which coincides with the angle φ (FIG. 1).

  A so-called tilted edge 18 is provided on the base portion 34 of the transverse member 32 on the main surface 39 in front of the transverse member 32. The tilting edge 18 forms a transition between the radially outer section or head section of the transverse member 32 and the tapered radially inner section or bottom section. Such tilting edge 18 and the tapered bottom section allow the transverse member 32 of the drive belt 3 to tilt relative to each other in the curved track portion of the drive belt 3 of the transmission.

  Further, the main surface 39 in front of the lateral member 32 is provided with a protrusion 40 at the top portion 36 of the lateral member 32. In the drive belt 3, the protrusion 40 is inserted into a hole 41 provided in the opposing surface of the adjacent lateral member 32, that is, the rear main surface 38. Such protrusions 40 and holes 41 serve to align the transverse members 32 with each other in the above-described row of transverse members 32.

  Finally, FIG. 4 shows a cross section of a known transmission. The drive belt 3 is shown sandwiched between pulley sheaves 4, 5 (slightly shown). The continuous transverse members 32 ′, 32 ″ of the drive belt 3 are inverted (in the axial direction). In other words, the recess 33 of such continuous transverse members 32 ′, 32 ″ is driven The belt 3 is open toward the opposite axial sides of the belt 3. In FIG. 4, the lateral member 32 ″ located on the rear side is indicated by a broken line and is located behind the lateral member 32 ′ located on the front side. The transverse members 32, 32 ′, 32 ″ , The endless carrier 31 of the transverse members 32, 32 ′, 32 ″ is completely surrounded in the plane of FIG. 4, that is, in the axial direction A and radial direction R of the drive belt 3. ing.

  FIG. 4 shows a typical structure of the endless carrier 31. The carrier 31 includes rings that are overlapped in the radial direction.

  FIG. 5 schematically shows a first embodiment of the present invention. In the first embodiment of the invention, the front main surface 39 of the transverse member 32 is designed to have two so-called contact areas 50, 60. These contact areas 50, 60 are indicated by hatching lines and are raised relative to the remaining other parts of the front main surface 39. In other words, at the location of the contact areas 50, 60, the thickness of the lateral member 32, that is, the distance or spacing between the front major surface 39 and the rear major face 38 of the lateral member 32 is the area 50, 60. 60 is larger than the outside.

  According to the present invention, the lower contact area 50 is provided in the base portion 34 of the transverse member 32, ie below the recessed portion 33 defined by the transverse member. It is located above the tilting edge 18. Another or upper contact area 60 is provided in the top portion 36 of the transverse member 32 in the vicinity of the radial upper portion of the transverse member 32. The two contact areas 50, 60 extend over the entire axial dimension of the transverse member 32. Furthermore, according to the present invention, the surface area of the upper contact area 60 is at least the same as the surface area of the lower contact area 50.

  In the drive belt 3, the transverse member 32 contacts the preceding transverse member at least initially at the contact areas 50, 60 of the transverse member 32. According to the invention, the precisely defined and clearly positioned contact areas 50, 60 provide a stable contact between successive transverse members 32, 32 ′, 32 ″ of the drive belt 3. However, vibrations are advantageously suppressed.

  In practice, the large thickness in the contact areas 50, 60 may be limited to tens of micrometers. This thickness is small compared to the nominal thickness of the transverse member 32 which is about 1.5 mm. Further, in practice, the boundary line between the contact areas 50 and 60 does not need to be clearly formed, and can be formed as a stepped inclined surface. According to the proposed definition, those portions of the front major surface 39 that are lower than the highest area of the associated contact area 50, 60 and less than 10 micrometers are located on each contact area 50, 60. It is considered to be a part.

  FIG. 7 schematically shows a third embodiment of the present invention. Also in this third embodiment of the present invention, the upper contact area 60 consists of two separated parts 60a, 60b, and the lower contact area 50 consists of two separated parts 50a, 50b. ing. Such contact area portions 50 a, 50 b, 60 a, 60 b are respectively arranged with respect to the respective axial side portions of the transverse member 32. The contact region portions 50a and 50b of the base portion 34 are separated from each other at an axial position that matches the axial position on the closed side of the recessed portion 33. Further, the protrusion 40 and the hole (not shown) are not provided in the top portion 36 of the lateral member 32, but are provided in the base portion 34 between the contact region portions 50a and 50b. . According to the invention, the projections 40 provided on the base part 34 have a mainly rectangular shape and at least radially and at least partially overlap the tilting edge 18. Of course, the hole (not shown) has a shape that can accommodate such a rectangular protrusion of the base portion 34 and overlaps the tilting edge 18.

Claims (9)

A transverse member for a drive belt to be used (3) in a continuously variable transmission with two driving wheels (1,2) (32), wherein between the two drive wheels (1, 2) The drive belt (3) is housed, the transverse member (32) is generally C-shaped and defines a centrally located recess (33), which is The lateral member (32) is open toward one axial side portion, and the lateral member (32) includes a base portion (34) disposed below the recessed portion (33). And a connecting portion (35) arranged side by side with the recessed portion (33) and a top portion (36) disposed above the recessed portion (33), and the transverse member (32) includes a transition between the top section of the transverse member (32) and the tapered bottom section. In tilting edges forming (18) is provided a transverse member for a drive belt for use in a continuously variable transmission (32),
The main surface (39) of the transverse member (32) is provided with at least two contact areas (50, 60), which are separate from the main surface (39). The lower contact area (50) of the at least two contact areas is disposed on the base part (34) above the tilting edge (18). An upper contact area (60) of the at least two contact areas is disposed on the top portion (36) in the vicinity of the upper portion of the transverse member (32) ;
The lower contact area (50) is composed of two parts (50a, 50b), and each part (50a, 50b) is arranged on each axial side part of the transverse member (32). Has been
The two portions (50a, 50b) of the lower contact area (50) are separated from each other at an axial position coinciding with the axially closed side of the recessed portion (33);
A transverse member for a drive belt used in a continuously variable transmission.   The surface area of the upper contact area (60) is the same as the surface area of the lower contact area (50) or is larger than the surface area of the lower contact area (50). Item 2. The transverse member according to Item 1.   The transverse member according to claim 1 or 2, wherein the lower contact area (50) and the upper contact area (60) extend to an axial side of the transverse member (32).   The upper contact area (60) is composed of two parts (60a, 60b), and each part (60a, 60b) is disposed on each axial side of the transverse member (32). The transverse member according to any one of claims 1 to 3. A protrusion (40) is provided between the two portions (50a, 50b) of the lower contact area (50), and the protrusion (40) precedes the drive belt (3). 5. The transverse member according to claim 1 , wherein the transverse member is accommodated in a recess (41) provided in a major surface (38) facing the transverse member (32). The protrusion (40) is mainly rectangular and is partially positioned alongside the tilting edge (18), the tilting edge (18) being partially interrupted by the protrusion (40). The transverse member of claim 5 . One portion (50b) of the lower contact area (50) is disposed below the recessed portion (33), and the extending length of the recessed portion (33) in the axial direction is large. 7. A transverse member according to any one of the preceding claims, extending partly or entirely. Said contact region (50, 60) and / or contact touch area portion (50b, 60, 60a, 60b), only relatively 5-100 micrometers relative to another portion of said major surface associated (39) The transverse member according to any one of claims 1 to 7 , which protrudes. Drive belt (3) comprising an endless carrier (31) and a plurality of transverse members (32) according to any one of claims 1 to 8 , wherein said endless carrier (31) Is accommodated in the recessed portion (33) of the transverse member (32), and the base portion (34) of the transverse member (32) is in the radial direction of the endless carrier (31). A drive belt, which is arranged on the inside.

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