Transverse section for a transmission belt and a transmission belt for a continuously variable transmission

Abstract

The invention relates to a transverse segment (10) of a drive belt (6) for a continuously variable transmission of the belt and pulley type, the drive belt (6) comprising a row of these transverse segments (10) mounted on a ring stack (9) consisting of a plurality of mutually nested rings. The transverse segment (10) is provided with a protrusion (40) protruding from its front surface (11) and a corresponding cavity (41) on its rear surface (12). According to the invention, an offset is provided between the protrusion (40) and the cavity (41) in the radial direction of the drive belt (6), so that in a row of transverse segments (10) in the drive belt (6), these transverse segments (10) will tilt backwards due to the protrusion (40) being forced into the cavity (41).

Description

Technical Field

[0001] The present invention relates to a transverse segment intended to form part of a drive belt for a continuously variable transmission having two pulleys and a drive belt. This type of drive belt is known from International Patent Application Publication WO 2015 / 063132 A1 and comprises a row of metal transverse segments mounted on a plurality of interlocking continuous metal belts, i.e., flat, thin rings. The transverse segments define grooves for accommodating and restraining corresponding circumferential segments of the ring stack, while enabling the transverse segments to move circumferentially along the stack. This particular type of drive belt is also known as a push belt or push belt. Background Art

[0002] In the following description, the axial, radial, and circumferential directions are defined relative to the belt when it is placed in a circular manner outside the transmission. Furthermore, the thickness dimension of the transverse segments is defined in the circumferential direction of the belt, the height dimension of the transverse members is defined in the radial direction, and the width dimension of the transverse segments is defined in the axial direction.

[0003] Conventional transverse segments each include a base portion, a middle portion, and a top portion. The middle portion of the transverse segment extends radially, interconnecting the base and top portions of the transverse segment. Between the base and top portions of the transverse segment, and on either side of the middle portion, corresponding grooves are defined for accommodating corresponding ring stacks of the drive belt. At each groove, its radially outward-facing bottom surface contacts and supports the ring stack in a radially outward direction. These bottom surfaces of the grooves associated with the base portion of the transverse segment are hereinafter referred to as bearing surfaces.

[0004] In a row of transverse segments of a drive belt, at least a portion of a front main surface (facing the direction of belt rotation) of a transverse segment abuts at least a portion of a rear main surface (facing rearward relative to the direction of belt rotation) of a corresponding preceding transverse segment in the row, while at least a portion of a rear main surface of a transverse segment abuts at least a portion of a front main surface of a corresponding subsequent transverse segment. At least one of these front and rear main surfaces of the transverse segment, for example the front main surface, includes an axially extending convex curved surface portion. This curved surface portion divides the front main surface into a radially outward surface portion and a radially inward surface portion oriented at an angle (obliquely) relative to each other. Adjacent transverse segments in the drive belt can tilt relative to each other while maintaining mutual contact at this curved surface portion, which is hereinafter referred to as an oblique edge, but is also referred to as a rocking edge in the prior art. The oblique edge enables the row of transverse segments of the drive belt to follow the local curvature of the ring stack imposed by the drive pulley.

[0005] The transverse segments are further provided with a protrusion, or stud, protruding from their front body surface and a cavity, or hole, recessed into their rear body surface. Within a row of transverse segments of the drive belt, the protrusion of a subsequent transverse segment is at least partially located within the cavity of the preceding transverse segment, thereby preventing independent displacement of adjacent transverse segments in a plane perpendicular to the circumferential direction of the drive belt, or at least limiting such independent displacement to the play of the stud within the cavity. Typically, the protrusion and cavity have similar overall shapes, for example, being predominantly cylindrical with a slight taper, or narrowing. However, because the protrusion is to be received within the cavity, the protrusion is somewhat smaller than the cavity, such that, in the drive belt, there is a gap in every direction between the outer periphery of the protrusion and the inner periphery of the cavity. In particular, in the case of a predominantly cylindrical protrusion, the height and diameter of the protrusion are smaller than the depth and diameter of the cavity.

[0006] Regarding the clearance of the protrusion within the cavity, JP2000-179626A teaches that, in order to suppress wear, a smaller clearance is provided at the bottom side of the protrusion than at its top side. In particular, in the case of a generally cylindrical shape, this clearance setting is achieved by positioning the protrusion somewhat lower than the cavity in a transverse section, whereby the centerline of the protrusion is positioned radially inward relative to the centerline of the cavity.

[0007] For the sake of completeness, it should be noted that an alternative design to the type of drive belt currently under consideration is known in the art, for example from International Patent Publication WO2018 / 210456-A1. This alternative drive belt design comprises only a single ring stack located in a single central opening in each transverse segment. This central opening is open to the radially outer side of the drive belt and is in turn defined between a base portion of the transverse segment and two columnar portions extending radially outward from a respective side of the base portion. In addition, transverse segments of this type are also typically provided with the above-mentioned protrusion-cavity pair, which is centrally arranged in the base portion and / or, in the case of two, is provided in each columnar portion.

[0008] During operation of these known drive belts, as seen in the direction of rotation of the belt during transmission, a relatively preceding transverse section rotates relative to a subsequent transverse section when it passes from a straight path portion of the belt between the pulleys into a curved path portion of the belt on the pulleys. In particular, in said curved path portion, the transverse sections are oriented relative to each other at an angle of inclination α, which is determined by the radius of curvature Rr of the curved path portion and the thickness t of the transverse section - or at least can be estimated as follows:

[0009] α[deg]=(180·t) / (π·Rr) (1)

[0010] In this relatively rotated orientation of two successive transverse segments, the two successive transverse segments can maintain mutual contact at the inclined edge of the succeeding transverse segment. Because this inclined edge is defined by a convex curve rather than a sharp edge, it can be geometrically deduced that as the successive transverse segments rotate relative to each other, the preceding transverse segment not only rolls off the inclined edge of the succeeding transverse segment but also slides radially outward on this inclined edge. While this radial sliding could theoretically cause some wear on the inclined edge and some in-belt friction losses, in practice, these effects are minimal. Summary of the Invention

[0011] However, according to the present invention, this radial slip leads to another, previously unnoticed, effect. The invention is based on the observation that by reducing this radial slip, the friction between the transverse segments and the pulleys is unexpectedly increased, also in their rotational direction, i.e., in the tangential direction. This additional effect is, of course, highly advantageous, as it enables the transmission to transmit higher torques or operate with lower normal forces between the drive belt and pulleys.

[0012] According to the present invention, an advantageous method for reducing the aforementioned radial slippage of the transverse segments is to arrange them relative to each other in a rearwardly tilted position relative to their ring stack in the straight path portion of the drive belt. This is achieved by positioning the protrusions low on the transverse segments, sufficiently low that the radially inner side, i.e., the bottom side, of the protrusions is positioned radially inwardly, i.e., below, the radial inner side of the cavities. This measure causes the transverse segments to tilt rearward within the rows of transverse segments in the drive belt, even when traveling in an otherwise straight line between the pulleys, as the protrusions are forced into the (higher-positioned) cavities. Consequently, the transverse segments enter the pulleys in this rearwardly tilted orientation, thereby advantageously reducing their radial slippage and / or advantageously increasing their tangential friction with the pulleys.

[0013] Another effect of the rearward inclination of the transverse segments is that the noise generated by the operation of the transmission belt, and in particular by the contact of the transverse segments with the pulleys, is advantageously reduced (by up to 10 dB). This unexpected but highly advantageous side effect of the invention can be attributed to the fact that the rearwardly inclined transverse segments enter the pulley more gradually than transverse segments oriented substantially perpendicular to the ring stack, i.e., oriented radially relative to the pulley when entering the pulley, so that the initial contact therebetween is more instantaneous.

[0014] Specifically, in the case where the protrusion and cavity are generally (substantially / substantially) cylindrical, according to the present invention, the centerline of the protrusion is positioned radially inward relative to the centerline of the cavity by an amount greater than the radial clearance between the protrusion and the cavity, CLO. This radial clearance can be approximated as half the difference between the (inner) diameter Dh of the cavity and the (outer) diameter Dp of the protrusion, so that the required centerline offset CLO is defined as follows:

[0015] CLO>0.5·(Dh-Dp) (2)

[0016] It should be noted that since the cavity and the protrusion are usually slightly conical, ie slightly conical, the diameters of the cavity Dh and the protrusion Dp are respectively compared at equal distances from the front body surface perpendicular to the rear body surface of the transverse section.

[0017] With the centerline offset CLO according to equation (2), when entering the curved track portion on the pulley, the transverse segment is tilted rearwardly relative to the radial direction at an inclination angle β which is determined—or at least estimated—as follows.

[0018] β=arctan((CLO-0.5·(Dh-Dp)) / t) (3)

[0019] In a preferred embodiment of the present invention, the upper and lower bounds for this tilt angle β are defined as follows:

[0020] (180·t) / (π·Rmax)≤β[deg]≤(180·t) / (π·Rmin) (4)

[0021] Here, Rmin represents the minimum radius of the curved track portion of the transmission belt that occurs in the transmission, and Rmax represents its maximum radius.

[0022] However, it is more preferable that the tilt angle β is equal to or less than half of the upper limit defined by equation (4). After all, the tilt angle halfway between the upper and lower limits already reduces the average value of the radial slip. Even more preferably, the tilt angle β is set equal to the lower limit defined by equation (4) to minimize any unwanted side effects of the present invention, such as a force acting on the protrusion to tilt the lateral segment backward.

[0023] For example, for a typical drive belt with an Rr_max value of 77 mm and a t value of 1.5 mm, the present invention specifies that the tilt angle β is preferably 1 degree. Combined with the typical radial clearance between the protrusion and the cavity of 0.025 mm, equation (3) specifies a centerline offset CLO of 0.050 mm. In this regard, practical values ​​for the centerline offset CLO range from 0.035 mm to 0.100 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention described above and its basic technical working principle will now be further described with reference to the accompanying drawings, in which:

[0025] - Figure 1 A schematic perspective view of a continuously variable transmission having a drive belt running over two pulleys is provided;

[0026] - Figure 2 A schematic cross-sectional view of a conventional drive belt in its circumferential orientation is provided;

[0027] - Figure 3 A schematic width-oriented view of a transverse segment of a conventional drive belt is provided;

[0028] - Figure 4 Schematically shows a circuit comprising a circuit according to the present invention. Figure 5 and Figure 6 The linear track portion of the drive belt of the novel transverse segment shown in;

[0029] - Figure 5 is a front view of a novel transverse segment according to the invention in a schematic cross-sectional view of a drive belt oriented along its circumference;

[0030] - Figure 6 yes Figure 5 An enlarged view of a detail of the novel transverse section is shown;

[0031] - Figure 7 The basic working principle of the present invention is schematically shown;

[0032] - Figure 8 is a diagram illustrating the beneficial technical effects brought about by the present invention compared with the known technology; and

[0033] - Figure 9 Relative to Figure 5 Alternatively, the invention is shown implemented in the basic design of a drive belt.

[0034] It is particularly noted that these drawings are schematic and, in particular, not drawn to scale. DETAILED DESCRIPTION

[0035] Figure 1A continuously variable transmission, such as that used in a motor vehicle between its main engine and drive wheels, is schematically illustrated. The continuously variable transmission is generally designated by reference numeral 1. The continuously variable transmission 1 comprises two pulleys 2, 3 and a drive belt 6 disposed in a closed loop around the pulleys 2, 3. Each pulley 2, 3 is provided with a pulley shaft 4 and two pulley sheaves 7, 8. The first pulley sheave 7 is fixed to the pulley shaft 4 of the respective pulley 2, 3, and the second pulley sheave 8 is axially movable relative to the pulley shaft 4 while being rotationally fixed. During operation of the transmission 1, the drive belt 6 is clamped at each pulley 2, 3 by and between the respective pulley sheaves 7, 8 at a running radius Rr. By moving the pulley sheaves 7, 8 of the pulleys 2, 3 toward or away from each other, the running radius Rr can be varied to change the speed ratio of the transmission.

[0036] The drive belt 6 comprises two sets of continuous belts or rings which are radially nested in each other, hereinafter referred to as the ring nesting set 9. The transverse sections 10 of the drive belt 6 are arranged on the ring nesting set 9 so as to form a substantially continuous row along its entire circumference, which for the sake of simplicity is Figure 1 Only a portion of these transverse segments 10 is shown.

[0037] The transverse segments 10 are arranged to be movable relative to the ring stack 9, at least in the circumferential direction of the ring stack 9. Thus, torque can be transmitted between the transmission pulleys 2, 3 by means of friction, with the transverse segments 10 pressing against each other and pushing each other forward in the direction of rotation of the pulleys 2, 3, along the circumferential direction of the ring stack 9. The transverse segments 10 of the drive belt 6 and (the rings of) the ring stack 9 are typically made of steel. This particular type of transmission 1 and its general operation are known per se.

[0038] exist Figure 2 In FIG, an exemplary embodiment of a drive belt 6 is shown in a cross-sectional view, which is oriented in its longitudinal or circumferential direction C, ie perpendicular to the width or axial direction A and the height or radial direction R of the drive belt 6. Figure 3 In the figure, only Figure 2 A side view of the transverse section 10 in the axial direction A.

[0039] exist Figure 2 , a ring stack 9 is shown in cross-section and a transverse section 10 of a drive belt 6 is shown in front view. The ring stack 9 in this case consists of five individual flat, thin and flexible annular rings 5, which are concentrically stacked on one another in the radial direction Rr to form the respective ring stack 9. In practice, however, these ring stacks 9 usually include more than five annular rings 5, for example nine or twelve or even possibly more annular rings 5.

[0040] exist Figure 2 and Figure 3 , the transverse segment 10 is shown as comprising, in succession in the radial direction Rr, a generally trapezoidal base portion 13, a relatively narrow middle portion 14, and a generally triangular top portion 15. On either side of the middle portion 14, grooves 33 are defined between the base portion 13 and the top portion 15, wherein the ring assemblies 9 are received in the grooves 33. At each groove 33, a radially outwardly facing bearing surface 42 of the base portion 13 contacts the radially inner side of the corresponding ring stack 9 during operation.

[0041] The front main surface of the transverse segment 10 is generally indicated by the reference numeral 11, and the rear main surface of the transverse segment 10 is generally indicated by the reference numeral 12. In the drive belt 6, at least a portion of the front main surface 11 of the transverse segment 10 abuts at least a portion of the rear main surface 12 of the corresponding subsequent transverse segment 10, and at least a portion of the rear main surface 12 of the transverse segment 10 abuts at least a portion of the front main surface 11 of the corresponding preceding transverse segment 10.

[0042] The transverse section 10 receives the clamping force exerted between the sheaves 7, 8 of each pulley 2, 3 via its contact surfaces 37, one such contact surface 37 being provided at each axial side of the transverse section 10. These contact surfaces 37 diverge from one another in the radially outward direction so as to define an acute angle therebetween, which is referred to as the belt angle and closely matches the pulley angle θ defined between the pulley sheaves 7 , 8 of the pulleys 2 , 3 .

[0043] The transverse segment 10 is provided with a protrusion 40 protruding from its front main surface 11 and a corresponding cavity 41 provided in its rear main surface 12. In the drive belt 6, the protrusion 40 of the subsequent transverse segment 10 is at least partially located in the cavity 41 of the preceding transverse segment 10, thereby preventing or at least limiting relative displacement between these successive transverse segments 10 in a plane perpendicular to the circumferential direction C of the drive belt 6. In the accompanying drawings, the protrusion 40 and the cavity 41 are depicted as cylindrical, however, protrusions 40 and cavities 41 of different shapes are also known. In particular, it is customary in the art to give them a slight taper, i.e., a narrowing. In any case, a nominal gap of between 10 and 30 microns is generally provided between the outer periphery of the protrusion 40 and the inner periphery of the cavity 41 (i.e., symmetrically in all directions).

[0044] At the front face 11 of the transverse segment 10, an inclined edge 18 is defined. The inclined edge 18 is represented by a convexly curved area of ​​the front body surface 11 which separates, in the radial direction Rr, two sections of said front body surface 11 which are oriented at an angle (obliquely) relative to each other, so that the transverse segment 10 narrows radially inwards below the inclined edge 18, i.e. in relation to the inclined edge 18. An important function of the inclined edge 18 is to provide mutual pushing contact between consecutive transverse segments 10 when said transverse segments 10 are in a slightly rotated, i.e. inclined, position relative to each other at the pulleys 2, 3. Figure 2 In the embodiment of the design, the inclined edge 18 is located in the base portion 13 of the transverse section 10, but it is also known to position the inclined edge 18 at least partially in the middle portion 14 of the transverse section 10 (see Figure 9 ).

[0045] An important function of the inclined edge 18 is to provide mutual pushing contact between rows of adjacent transverse segments 10 of the drive belt 6 when these segments are in a slightly rotated, i.e., tilted, position relative to each other at the pulleys 2, 3. Specifically, as the leading transverse segment 10 of a pair of successive transverse segments 10 enters between the two pulley sheaves 7, 8 of the pulleys 2, 3, the leading transverse segment 10 rotates relative to the following transverse segment 10 of the pair that has not yet entered the pulleys 2, 3, while the rear surface 12 of the leading transverse segment 10 maintains contact at the inclined edge 18 on the front surface 11 of the following transverse segment 10. Because the radius of curvature of the inclined edge 18 of the following transverse segment 10 is non-zero, the axially oriented contact line between the following transverse segments 10 shifts radially inward as the rotation of the following transverse segments 10 relative to each other increases. Since the inclined edge 18 of the subsequent transverse segment 10 is convexly curved, while the rear surface 12 of the preceding transverse segment 10 is flat, this radial inward displacement is different for these transverse segments 10. Therefore, in order to keep the consecutive transverse segments 10 aligned in the radial direction R, sliding occurs between them when the transverse segments 10 rotate relative to each other. Although this sliding movement is only minimal, after reducing it according to the present invention, a significant beneficial effect on the transmission performance is observed (see Figure 8 ).

[0046] According to the invention, by placing the transverse section 10 in a rearwardly inclined position in the straight section, i.e. the straight track portion, of the drive belt 6, Figure 4As shown in , the above-mentioned sliding movement can be advantageously reduced. Here, the protrusion 40 of the transverse segment 10 is positioned lower relative to its cavity 41, that is, radially inward, until the radial inner side, that is, the bottom side of the protrusion 40 is positioned radially inward, that is, below, relative to the radial inner side of the cavity 41. The new transverse segment design is as follows Figure 5 In this case, when the projections 40 of the respective subsequent transverse segments 10 are forced into the (higher) cavities 41 of the respective preceding transverse segments 10, these transverse segments 10 are forced to tilt backwards relative to the circumferential direction C, i.e. relative to the ring stack 9, when they are pressed together in the rows of transverse segments 10 of the drive belt 6.

[0047] Furthermore, according to the present invention, particularly in the case of its cylindrical shape as shown, Figure 6 As shown in detail in FIG, an offset CLO can be applied in a radially inward direction between the center line CA40 of the protrusion 40 and the center line CA41 of the cavity 41, which offset CLO exceeds half the value of the difference between the diameters of the cavity 41 and the protrusion 40, that is, exceeds the nominal gap therebetween.

[0048] exist Figure 7 In FIG. 1 , the effect of the rearward tilting of the transverse section 10 is shown, which is the basic working principle of the present invention. Figure 7 Figures AF respectively show the front surface 11 with the inclined edge 18 and the support surface 42 of the subsequent transverse segment 10a at the location of the base portion 13, and the rear surface 12 and the support surface 42 of the preceding transverse segment 10b at the location of the base portion 13. Figure 7 The top row of images A, B, and C illustrate conventional transverse segments 10, specifically the contact between two consecutive transverse segments 10a, 10b. In image A, consecutive transverse segments 10a, 10b are shown aligned parallel to one another, substantially perpendicular to the circumferential direction C of the drive belt 6 in its straight path portion. In a vertical arrangement, the consecutive transverse segments 10a, 10b contact one another via at least a first, axially oriented line of contact LC1 at the upper end of the inclined edge 18 of the subsequent transverse segment 10a. In image B, the consecutive transverse segments 10a, 10b are shown tilted relative to one another in a curved path portion of the drive belt 6 at the pulleys 2, 3. In this tilted arrangement, the consecutive transverse segments 10a, 10b contact one another via a second, axially oriented line of contact LC2, extending within the extension of the inclined edge 18 of the subsequent transverse segment 10a, i.e., radially inward of the first, axially oriented line of contact LC1.

[0049] However, Figure 7The tilting between the successive transverse segments 10a, 10b shown in Figures A and B cannot be a pure rolling-off of the (flat) rear surface 12 of the preceding transverse segment 10b on the (convexly curved) inclined edge 18 of the following transverse segment 10a, but must be accompanied by a sliding movement. Otherwise, i.e., in the case of a pure rolling-off movement, as shown in Figure C, the bearing surface 42 of the preceding transverse segment 10b would be radially further away from the second contact line LC2-10b than the bearing surface of the following transverse segment 10a (LC2-10a), which is not permitted by the pulleys 2, 3, wherein the sheaves 7, 8 exert a common radial positioning on the transverse segments 10 in the corresponding curved path portion of the drive belt 6.

[0050] However, according to the present invention, it is possible and preferred to reduce the above-mentioned sliding movement by making the radially inward displacement of the contact line between consecutive transverse segments 10a, 10b equal. Figure 7 The bottom row of pictures D, E and F show a novel transverse segment 10 that achieves this equalization.

[0051] In Figure D, two consecutive, novel transverse segments 10a, 10b are depicted arranged parallel to one another in a straight portion of the belt 6, with a first line of contact LC1 between them. Unlike the known belt 6, these novel transverse segments 10a, 10b are tilted rearward at an angle β relative to the circumferential direction C of the belt 6. In Figure E, these novel transverse segments 10a, 10b are shown tilted relative to one another in a curved portion of the belt 6 at the pulleys 2, 3, with a second line of contact LC2 between them. As shown in Figure F, the bearing surfaces 42 of these novel transverse segments 10a, 10b are located at corresponding radial distances relative to this second line of contact LC2, advantageously eliminating the need for sliding movement, or at least net sliding movement, between the transverse segments 10a, 10b. In particular, the rearward tilting of the novel transverse segments 10 increases the radial distance between the first and second lines of contact LC1, LC2 on the inclined edge 18, while decreasing this radial distance on the rear surface 12.

[0052] In addition, Figure 7 , particularly in Figure F thereof, illustrates another feature of the transverse segment 10 according to the present invention. Specifically, the support surface 42 of the novel transverse segment 10 is preferably oriented at an angle of less than 90 degrees relative to its rear surface 12. In this manner, the rearward tilt of the transverse segment 10 in the straight path portion of the drive belt 6 is at least partially compensated, thereby approaching the preferred orientation of the support surface 42 parallel to the ring stack 9. In this regard, the support surface 42 is preferably oriented at 90 degrees minus the tilt angle β.

[0053] exist Figure 8 The beneficial technical effects brought about by the present invention compared with the known technology are shown in FIG. Figure 8 Graph showing a parameter S which is inversely proportional to the efficiency with which the drive belt 6 can transmit the torque T between the pulleys 2 , 3 , versus the amount of the torque T transmitted. Figure 8 The dotted line CB in FIG. 5 represents the measurement results obtained using the conventional drive belt 6, and the solid line NB represents the measurement results obtained using the new drive belt 6 according to the present invention. Figure 8 It is intuitively shown that the new drive belt 6 performs better in substantially the entire torque T range, and its efficiency advantage increases with the increase of torque T. Figure 8 It is observed that the novel drive belt 6 can transmit a higher maximum torque T to a certain extent than the conventional drive belt 6 .

[0054] It should be pointed out that the present invention is not limited to Figures 1 to 6 The basic design of the transverse segments 10 shown in FIG has two ring stacking groups 9 located on both sides of the middle part 14. Rather, the present invention is applicable to any type of drive belt 6 comprising transverse segments 10 that are individually and movably mounted on at least one ring stacking group 9. In this respect, Figure 9 A different type of drive belt 6 is shown, which, in cross section, comprises only one ring nesting group 9. In this case, the transverse segment 10 is provided with a single central cutout 16, located between two cylindrical portions 17 extending radially outward from either axial side of its base portion 13. Each of these cylindrical portions 17 includes a hook portion 18 projecting above the central opening 5, for retaining the ring nesting group 9 in the central cutout 16. Furthermore, each cylindrical portion 17 is provided with a protrusion 40 and a recess 41, wherein, according to the invention, the protrusion 40 is lowered on the respective cylindrical portion 17 until the bottom edge of the protrusion 40 is below the bottom edge of the cavity 41.

[0055] In addition to all the details described above and all the details of the drawings, the present disclosure also relates to and includes all the features of the claims. Reference numerals in parentheses in the claims do not limit the scope of the claims but are merely intended to provide non-limiting examples of the corresponding features. The claimed features may be applied individually to a given product or process, as the case may be, but any combination of two or more of these features is also possible.

[0056] The invention set forth in this disclosure is not limited to the embodiments and / or examples explicitly mentioned herein, but encompasses modifications, changes, and practical applications of the embodiments and / or examples within the scope accessible to those skilled in the art.

Claims

1. A transverse section (10) for a drive belt (6), the drive belt (6) being provided with a ring-piece stacking group (9) consisting of a plurality of belts embedded in each other and a plurality of transverse sections (10) movably arranged in a row on the ring-piece stacking group (9), the transverse section (10) defining a groove (33) for accommodating the ring-piece stacking group (9), the groove (33) being defined in a radially inward direction by a bearing surface (42) of a base portion (13) of the transverse section (10) for supporting the radial inner side of the ring-piece stacking group (9), the transverse section (10) further comprising a portion (15; 17) positioned radially outward relative to the ring-piece stacking group (9) when incorporated into the drive belt (6), in which a protrusion (40) is provided on the front surface (11) of the transverse section (10) and a cavity (41) is provided on the oppositely positioned rear surface (12) of the transverse section (10), characterized in that The protrusion (40) is positioned radially inwardly on the front surface (11) relative to the position of the cavity (41) on the rear surface (12) such that the radial inner side of the protrusion (40) is positioned radially inwardly relative to the radial inner side of the cavity (41).

2. The transverse section (10) according to claim 1, characterized in that The protrusion (40) and the cavity (41) of the transverse section (10) have a generally cylindrical shape, wherein the outer diameter of the protrusion (40) is smaller than the inner diameter of the cavity (41), and the center line (CA40) of the protrusion (40) is positioned radially inward relative to the center line (CA41) of the cavity (41) so that the mutual spacing between the center line (CA40) of the protrusion (40) and the center line (CA41) of the cavity (41) in the radial direction is greater than half the difference in diameter between the protrusion (40) and the cavity (41).

3. The transverse section (10) according to claim 2, characterized in that The spacing in the radial direction has a value in the range of 0.035 mm to 0.100 mm.

4. Transverse segment (10) according to any one of the preceding claims, characterized in that The transverse segment (10) is provided with an inclined edge (18) in the form of a region on its front surface (11) which is convexly curved in the radial direction and extends perpendicularly to the radial direction along the width of the transverse segment (10).

5. The transverse section (10) according to any one of claims 1 to 3, characterized in that The angle between the support surface (42) of the transverse section (10) and the rear surface (12) is less than 90 degrees.

6. A drive belt (6) comprising a ring stack (9) consisting of a plurality of belts nested in one another, and transverse segments (10) according to any one of the preceding claims, which are arranged movably in a row of transverse segments (10) on the ring stack (9), the projections (40) of the transverse segments (10) being located in the cavities (41) of the corresponding adjacent transverse segments (10) in the row of transverse segments (10), characterized in that At least in the straight section of the drive belt (6), the transverse section (10) is tilted rearward relative to the ring stack (9), so that the angle (β) between the rear surface (12) of the transverse section (10) and the ring stack (9) is less than 90 degrees.

7. The transmission belt (6) according to claim 6, characterized in that The angle between the support surface (42) of the transverse section (10) and the rear surface (12) is equal to 90 degrees minus the angle (β) at which the transverse section is tilted rearward relative to the ring stack (9).

Images