WO2021136576A1

WO2021136576A1 - A drive belt comprising different types of transverse segments for a continuously variable transmission and a blanking process for manufacturing such transverse segments

Info

Publication number: WO2021136576A1
Application number: PCT/EP2019/025492
Authority: WO
Inventors: Dirk Jan DE KUYPER
Original assignee: Robert Bosch Gmbh
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2021-07-08

Abstract

The invention concerns a drive belt (50) comprising a ring stack (8) and a plurality of transverse segments (1) that each define a central opening (5) between a base part (10) and two pillar parts (11) thereof, whereof one pillar part (11-n) is provided with an undercut (7) relative to the other one pillar part (11-b) and whereof the other one pillar part (11-b) is provided with a side face (14) facing the central opening (5). According to the invention, at least three subtypes (la-lf; lla-llf) are incorporated in the drive belt (50) having contours that are mutually different in at least one design aspect thereof with the exception of, at least, the side faces (14) of the said other one pillar part (11-b) that coincides between two of said at least three subtypes (la-lf; lla-llf).

Description

A DRIVE BELT COMPRISING DIFFERENT TYPES OF TRANSVERSE SEGMENTS FOR A CONTINUOUSLY VARIABLE TRANSMISSION AND A BLANKING PROCESS FOR MANUFACTURING SUCH TRANSVERSE SEGMENTS

This invention relates to a drive belt for a continuously variable transmission with two pulleys and the drive belt. Such a transmission is commonly known and is, for example, applied in the drive train of passenger cars and other motor vehicles. In the transmission the drive belt runs around and between the pulleys that are each provided with two conical sheaves that define a V-groove wherein a respective circumference part of the drive belt is held. The width of the V-groove of the pulleys can be changed in mutually opposite directions, by moving the pulley sheaves towards, respectively away from one another, to control a radius at which the drive belt is (effectively) in friction contact with the respective pulleys, i.e. to control a speed ratio provided by the transmission within a continuous range between a smallest and a largest speed ratio.

A known type of drive belt comprises an essentially contiguous row of individual transverse segments made of steel that are mounted on and around the circumference of a ring stack composed of a number of flexible endless bands or rings that are mutually stacked, one around the other, and that are likewise made of steel.

In the above and below description, the axial, the radial and the circumference directions are defined relative to the drive belt when placed in a circular posture. A thickness direction and a thickness dimension of the transverse segments are defined in the said circumference direction, a height direction and a height dimension of the transverse segments are defined in the said radial direction and a width direction and a width dimension of the transverse segments are defined in the said axial direction. A thickness direction and a thickness dimension of the rings and of the ring stack are defined in the said radial direction, a width direction and a width dimension of the rings and of the ring stack are defined in the said axial direction and a length direction and a length dimension of the ring stack is defined in the said circumference direction.

The known flexible ring is provided with an essentially rectangular cross-section, albeit with rounded side surfaces, such that its thickness is much smaller than its width, typically by a factor of at least forty to one hundred or more. Also in absolute terms, the thickness of the ring is small and typically has a value of 185 to 200 micrometer, such that it can bend relatively easily in its circumference direction. In the ring stack, a number of such rings are arranged mutually concentric, i.e. are nested with minimal play, such that these share the load when the drive belt is operated in the transmission.

The known transverse segments each define a central opening that is open towards the radial outside of the drive belt and that accommodates and confines a respective circumference section of such ring stack, while allowing the transverse segment to move along the circumference thereof. This central opening is defined by and between a base part of the transverse segment that is located radially inward of the ring stack and two pillar parts thereof that respectively extend from a respective side of the base part in radial outward direction. The two pillar parts thus define respective axial boundaries of the central opening, whereas in radial inward direction the central opening it is bounded by the base part. In radially outward direction the central opening is at least partly closed by respective hook portions of the pillar parts that each extend axially towards the respectively other, i.e. axially opposite, pillar part at some distance away from the base part. This particular drive belt design is known from the international patent publication WO2018/210456-A1.

During operation in the transmission, the ring stack is tensioned by the transverse segments being urged in radial outward direction at the two pulleys by being clamped between the conical sheaves thereof. At these pulleys, the drive belt thus follows a curved trajectory, in which curved trajectory parts the transverse segments bear against the radial inside of the ring stack through, at least, a part of the surface of their base part that is located between the pillar parts, which surface part is denoted support surface hereinafter. Due to the said tensioning thereof at the pulleys, the ring stack extends essentially straight between the two pulleys, while guiding the transverse segments as these traverse from the one pulley to the other in such straight trajectory parts.

As seen in radial direction, an outer portion of the known transverse segment is provided with an essentially constant thickness, whereas a thickness of an inner portion thereof decreases in radially inward direction. In between the said inner and outer portions, a front surface of the transverse segment, facing in a circumference direction of the drive belt, includes a width-wise extending surface part that is curved in radial direction and that is often referred to in the art as a rocking edge or a tilting zone. The rocking edge allows successive transverse segments in the drive belt to mutually rotate about the axial direction, while these remain in contact at the rocking edge, whereby the drive belt as a whole follows a curved trajectory. Although the rocking edge can be located in the base part of the transverse segment, it is preferably located at least partly in the pillar parts thereof. In this case, the rocking edge consists of two separate sections that are mutually separated by the central opening and/or by a curved transition between the support surface and the front main body surface of the transverse segment that is recessed in thickness direction relative to the rocking edge. Via such relatively recessed transition, a flow of lubricant is allowed between the successive transverse segments from radial inside the drive belt to the radial inside of the ring stack for lubricating and/or cooling the relative movement between the transverse segments and the ring stack. For the same purpose, the rocking edge that is located in the base part is preferably interrupted, i.e. is split into two or more separate sections, by one or more channels or recessed areas in the front main body surface that intersect the rocking edge in height direction.

It is common practice in the art to provide the transverse segment with a protrusion projecting from the said front surface or from an oppositely facing rear surface thereof and with a corresponding, however somewhat larger cavity in its respectively opposite main surface. In the row of transverse segments in the drive belt, the protrusion of a first transverse segment is received in the cavity of a second, successive transverse segment, at least in part. Hereby, a mutual displacement of the respectively successive transverse segments perpendicular to the circumference direction of the drive belt is limited to a play of the protrusion inside the cavity. The protrusions and cavities thus serve to both mutually align the transverse segments in a row in the straight parts of the drive belt’s trajectory and to limit a rotation thereof in the said curved trajectory parts. In particular, at least a pitching (i.e. rotation about the axial direction) and a yawing (i.e. rotation about the radial direction) of the transverse segments and preferably also a rolling (i.e. rotation about the tangential direction) of the transverse segments relative to the ring stack is limited thereby. The known transverse segments each include two protrusions (and corresponding cavities), one provided in each of it pillar parts.

According WO2018/210456-A1 two types of transverse segments are included in the drive belt, each having an asymmetric design that is axially mirrored between the said two types. In particular, one of the two pillar parts of the transverse segment is provided with an undercut, i.e. pocket, in axial direction, merging with, i.e. contiguous to the central opening. In other words, the undercut or pocket is formed in the said one pillar part, opening to the central opening. Hereby, effectively, the width of the said one pillar part is locally reduced relative to the width of the opposite pillar part, at least at the radial level of the support surface. Furthermore, in a first of the said two types of transverse segment the undercut is provided in, for instance, the left-side pillar part and in a second of the said two types of transverse segments the undercut is then provided in the right-side pillar part. By the presence of the undercuts, the transverse segments can be mounted on the ring stack, by inserting the ring stack under the hook portion into the undercut. Thus, the first type of transverse segments, whereof the left-side pillar parts are provided with the undercut, are placed to the left axial side of the ring stack and are moved to the right with respect to the ring stack for mounting these. The second type of transverse segments, whereof the right- side pillar parts are provided with the undercut, are placed to the right axial side of the ring stack and are moved to the left with respect to the ring stack for mounting these. Further according to WO2018/210456-A1 the said two types of transverse segments are arranged mutually alternating in the row of transverse segments of the drive belt. In the thus assembled drive belt, the ring stack is contained in both axial directions every other transverse segments, in particular by arriving in contact with a side face facing the central opening of the respective pillar part without the undercut thereof.

It is well-known in the art that such an alternating sequence of two types of transverse segments in the drive belt produces more, at least more perceptible noise during operation of the transmission than a non-alternating ordering thereof, such as random, pseudo-random or predetermined sequence. Such a non-alternating sequence of the two types of transverse segments thus includes sets of two or more consecutive transverse segments of the same type in the said row thereof. Nevertheless, according to WO2018/210456-A1, the alternating sequence is preferred in order to optimally confine the ring stack in axial direction, i.e. to equally distribute and minimize the contact forces between the ring stack and the transverse segments in axial direction.

The present invention sets out to reconcile these two, seemingly contradicting technical desires of, on the one hand, the optimal axial confinement of the ring stack and, on the other hand, minimizing the noise produced during operation of the transmission.

According to the invention, such aim is relation by including an additional type of the transverse segments in the drive belt, which additional type of transverse segment differs from the said two types in terms of the contour, i.e. design, thereof with the exception of, at least, the said side face of the pillar part without the undercut that coincides with the corresponding side face of one of the two types of transverse segments. By such different design, a mass and/or stiffness, i.e. a dynamic behaviour of the transverse segment of the additional type will be different as well, in particular in its interaction with the transmission pulleys. By mixing-in this additional type of transverse segment between the two types of transverse segments, a non-alternating sequence thereof can be realized without necessarily compromising the said optimal, i.e. alternating left and right, axial confinement of the ring stack. As mentioned hereinabove, such a non-alternating transverse segment sequence advantageously reduces the operating noise of the transmission.

Obviously, more than one such additional type of transverse segment can be included in the drive belt, to increasingly differentiate between the dynamic behaviour of the transverse segments and to increasingly enable an irregular ordering thereof in the row of transverse segments of the drive belt. In particular in this respect, it is noted that the transverse segments are known to be simultaneously blanked in pairs, quadruplets or even octuplets. According to the present invention, at least two of such simultaneously blanked transverse segments are provided with the said undercut on the same side thereof, i.e. in the same left- or right-side pillar part thereof and with the same design of the said side face of the opposite pillar part that is without the undercut, while otherwise being provided with a different contour in accordance with the present invention. In this way, the present invention is implemented in a relatively simple and easily to be monitored manufacturing process. Preferably in this respect, all of the said simultaneously blanked transverse segments are provided with a (mutually) different contour. In the latter case, two machines are implemented for blanking the transverse segments of the drive belt, i.e. one machine for blanking transverse segments with the undercut in the left-side pillar part and the other machine for blanking transverse segments with the undercut in their right-side pillar part.

The above-described invention will now be explained further with reference to the drawing figures, whereof:

- figure 1 is a simplified and schematic side elevation of a known transmission with two pulleys and a drive belt consisting of a ring stack and a row of transverse segments mounted on the ring stack along the circumference thereof;

- figure 2 provides an example of the known drive belt including two transverse segments types/designs; and

- figure 3 provides five novel types of transverse segment in accordance with the present invention, i.e. as variants of one of the two known types thereof.

Figure 1 schematically shows, in a cross-section thereof, the central parts of a continuously variable transmission 51 for use in a driveline of, for example, passenger motor vehicles. This transmission 51 is well-known and comprises at least a first variable pulley 52, a second variable pulley 53 and a drive belt 50 fitted around these pulleys 52, 53. In the driveline, the first pulley 52 is coupled to and driven by a prime mover of the vehicle, such as an electric motor or a combustion engine, and the second pulley 53 is coupled to and drives a driven wheel of the vehicle, typically via a number of gears. The pulleys 52, 53 each typically comprise a first conical sheave that is fixed to a respective pulley shaft 54, 55 and a second conical sheave that is axially displaceable relative to such respective pulley shaft 54, 55 and that is fixed thereto in rotational direction. As appears from figure 1, the trajectory of the drive belt 50 in the transmission 51 includes two straight parts ST, where the drive belt 50 crosses over between the pulleys 52, 53 and two curved parts CT where the drive belt 50 is wrapped around the two pulleys 52, 53 while being accommodated between the conical sheaves thereof.

The drive belt 50 is composed of a ring stack 8 and a plurality of transverse segments 1 that are mounted on the ring stack 8 along the circumference thereof in an, at least essentially, contiguous row. For the sake of simplicity, only a few of the transverse segments 1 of the drive belt 50 are shown in figure 1, which transverse segments 1 are, moreover, not drawn to scale in relation to, for example, the diameter of the pulleys 52, 53. In the drive belt 50, the transverse segments 1 are movable along the circumference of the ring stack 8, which ring stack 8 is composed of a number of relatively thin and flexible endless steel bands or rings that are mutually nested, as can be seen more clearly in figure 2 that shows the ring stack 8 with eight individual rings.

During operation of the transmission 51, the transverse segments 1 of the drive belt 50 can be driven by the first pulley 52 in the direction of rotation thereof by friction. These driven transverse segments 1 push preceding transverse segments 1 in the circumference direction of the ring stack 8 and, ultimately, rotationally drive the second pulley 53, again by friction. In order to generate such friction (force) between the transverse segments 1 and the pulleys 52, 53, the said pulley sheaves of each pulley 52, 53 are urged towards each other, whereby these clamp the transverse segments 1 between them in the respective curved trajectory part CT of the drive belt 50. To this end, electronically controllable and hydraulically acting movement means (not shown) that act on the moveable pulley sheave of each pulley 52, 53 are provided in the transmission 51. These movement means also control respective radial positions R1 and R2 of the drive belt 50 at the pulleys 52, 53 and, hence, the speed ratio that is provided by the transmission 51 in the driveline between the pulley shafts 54, 55 thereof.

Also during operation of the transmission 51 drive belt 50, the transverse members are urged radial outward by being clamped between the conical pulley sheaves and are being forced into contact with the radial inside of the ring stack 8 that is tensioned thereby. Since, as mentioned hereinabove, in the drive belt 50 the transverse segments 1 can move relative to the ring stack 8 along the circumference thereof, the ring stack 8 is tensioned to a relatively low level in relation to a torque transmitted by the drive belt 50 between the pulleys 52, 53, at least compared to other types of drive belt.

In figure 2 a known example of the drive belt 50 is schematically illustrated. At the top of figure 2, the drive belt 50 is shown in cross-section and at the bottom of figure 2 the front elevations and a side elevations of only the transverse segments 1 thereof are included. On either axial side thereof, the transverse segments 1 are provided with a side face 12, which side faces 12 arrive in (friction) contact with the transmission pulleys 52, 53 and are mutually oriented at an angle that closely matches an angle that is defined by and between the conical pulley sheaves of the transmission pulleys 52, 53. In practice, these side or pulley contact faces 12 are either corrugated by a macroscopic profile or are provided with a rough surface structure (not shown), such that only the higher lying parts or peaks of the corrugation profile or of the surface roughness arrive in contact with the transmission pulleys 52, 53. This particular feature of the design of the transverse segments 1 provides that the friction between the drive belt 50 and the transmission pulleys 52, 53 is optimised by allowing cooling oil that is applied in the known transmission 51 to be accommodated in the lower lying parts or troughs of the corrugation profile or of the surface roughness.

Each transverse segment 1 includes a base part 10 and two pillar parts 11, whereof the base part 10 extends mainly in the axial direction of the drive belt 50 and whereof the pillar parts 11 extend mainly in the radial direction of the drive belt 50, each from a respective axial side of the base part 10. In its thickness direction, the transverse segment 1 extends between a front main body surface, i.e. front surface 2 and a rear main body surface, i.e. rear surface 3 thereof that are both oriented, at least generally, in the circumference direction of the drive belt 50. An opening 5 is defined centrally between the pillar parts 11 and the base part 10 of each transverse segment 1, wherein a circumference section of the ring stack 8 is accommodated. A radially outward facing surface part 15 of the base part 10, forming the radially inner boundary of the central opening 5, supports the ring stack 8 from the radial inside and is denoted support surface 15. This support surface 15 is typically convexly curved for promoting a preferred, centred alignment of the ring stack 8 during operation, i.e. rotation of the drive belt 50 in the transmission 51. In radial outward direction the central opening 5 is partly closed-off by respective hook portions 13 of the pillar parts 11. Each such hook portion 13 extends from a respective pillar part 11 generally in the direction of the respectively opposite pillar part 11. Thus, the hook portions 13 confine the ring stack 8 to the central opening 5 of the transverse segment 1 in radial outward direction.

Both pillar parts 11 of the transverse segment 1 are provided with a stud 6 that protrudes in thickness direction from the front surface 2 of the transverse segment 1 and with a corresponding cavity (not shown) in the opposite side of the respective pillar part 11, i.e. in the rear surface 3 of the transverse segment 1. In the drive belt 50, the studs 6 of a first transverse segment 1 are received in the cavities of a second, adjacent transverse segment 1. By this engagement of the studs 6 and the cavities of adjacent transverse segments 1, the transverse segments 1 mutually link to and align one another in the said row thereof in the drive belt 50 at least in the virtual plane oriented perpendicular to the circumference direction.

Also in the row of transverse segments 1 in the drive belt 50, at least a part of the front surface 2 of a first transverse segment 1 abuts against at least a part of the rear surface 3 of a second, adjacent transverse segment 1. Abutting transverse segments 1 are able to tilt relative to one another, while remaining in mutual contact at and through an axially extending, convexly curved surface part 4 of the front surfaces 3 thereof, which surface part 4 is denoted a rocking edge 4 hereinafter. Above, i.e. radially outward of such rocking edge 4, the transverse segment 1 has an essentially constant thickness, whereas below, i.e. radially inward of such rocking edge 4, the transverse segment 1 is tapered, i.e. has a thickness that decreases in radially inward direction (whether gradually, stepwise or by a combination thereof), to allow for the afore-mentioned relative tilting without interference between the respective base parts 10 of the abutting transverse segments 1. It is noted that, in the embodiment of the transverse segment 1 of figure 2, the rocking edge 4 consists of two axially separate, but radially aligned, sections located in the pillar parts 11. The rocking edge 4 can, however, also be located partly or holy in the base part 10. Moreover, although it is illustrated in figure 2 as a horizontal line, in practice the rocking edge 4 has an extend in radial direction.

In the illustrated example of the known drive belt 50, one pillar part 11-n of every transverse segment 1 is provided with an undercut 7, i.e. is more narrow radially inward of its respective hook portion 13, as compared to the other, opposite pillar part 11-b that is broader. Moreover, two types I, II of transverse segments 1 are included in the drive belt 50, whereof the respective undercuts 7, i.e. the narrower and broader pillar parts 11; 11-n, 11-b are respectively located on opposite axial sides of the transverse segments 1 of each such type I, II. In particular, a first type I of transverse segment 1 is provided with the undercut 7 on the left-side of its body part 10 (i.e. as seen in and defined relative to the front elevation thereof in figure 2), whereas for a second type II of transverse segment 1 such undercut 7 on the right-side of the body part 10.

The design feature of the undercut 7 of the transverse segments 1 is known to facilitate the assembly of the drive belt 50, while the axial confinement of the ring stack 8 can still be realised every other transverse segment 1 by alternating the said two types I, II of transverse segments 1 in the row of transverse segments 1 in the drive belt 50. In particular, the ring stack 8 is then alternatingly confined respectively to right and to the left by arriving in contact with the broader pillar part 11-b, in particular by a side face 14 thereof facing the central opening 5, of the transverse segments 1 of the first type I and of the second type II respectively. However, a disadvantage of such an alternating sequence of the transverse segment types I, II is that the minimal noise that is typically emitted as each transverse segment 1 enters between the pulley sheaves of the pulleys 52, 53 is amplified thereby, or, at least, becomes more perceptible to the human ear.

According to the present invention an improvement can be obtained in the above respect, i.e. the operating noise and/or the amplification thereof can be reduced, by differentiating at least one type I of the two main types I, II of transverse segments 1 into two or more subtypes la-lf, such as illustrated in figure 3 by way of example, while maintaining the alternating sequence of the two main transverse segment types I, II. In particular, the said subtypes la-lf of a main transverse segment type I, II share, at least, the design of the side face 14 of the broader pillar part 11-b, in particular the positioning thereof in relation to the support surface 15, while differing in at least one other design aspect. In this way, the strictly alternating sequence of only two transverse segment types I, II is broken, while the ring stack 8 is still confined alternatingly to the left and right axial directions by successive transverse segments 1.

Specifically, the transverse segment subtypes la-lf illustrated in figure 3 represent the differing design aspects of:

- the subtype lb having a concave bottom surface 20 of its base part 10 compared to the straight bottom surface of the subtype la that corresponds to the type I transverse segment design of figure 2;

- the subtype lc having two, axially symmetrically arranged, holes 21 in its base part 10, compared to the solid base part 10 of the subtype la;

- the subtype Id having a single, axially asymmetrically arranged, hole 22 in its base part 10 compared to the solid base part 10 of the subtype la;

- the subtype le having an undercut 23 of lesser axial extent compared to the undercut 7 of the subtype la; and

- the subtype If having an undercut 24 defined by a differently oriented side face 25 compared to the undercut 7 of the subtype la.

In relation to the subtype Id it is noted that this may be preferred over the subtype lc, because the asymmetrically arranged hole 22, for example in the illustrated axial position thereof, can at least partly compensate for an asymmetry in the axial weight distribution resulting from the undercut 7.

Preferably, both main types I, II of the transverse segments 1 are each differentiated into two or more subtypes la-lf, such that the drive belt 50 includes at least four different transverse segments 1. In this latter respect it is noted that the respective differing design aspect of the subtypes la-le of the said one main type I of transverse segment 1 illustrated in figure 3, can be correspondingly incorporated in the other one main type II of transverse segment 1, thus creating a respective subtype lla-llf of that other one main type II. Preferably, the sub-types la-lf; lla-llf of a respective main transverse segment type I, II are mutually arranged non-cyclically in the row of transverse segments 1 of the drive belt drive belt 50. For example, in case two subtypes la, lb; lla, lib per main transverse segment type I, II the following non-cyclic arrangement thereof:

... la, lla, lb, I la, lb, lib, lb, I la, la, lib, la, lib, lb, ... is preferred over either one of the two possible cyclic arrangements thereof: la, lla, lb, lib, etc. ..., la, lib, lb, lla, etc.

Obviously, the more subtypes la-lf are incorporated in the drive belt per main transverse segment type I, II, the longer a non-self-repeating sequence thereof can be.

The present invention, in addition to the entirety of the preceding description and all details of the accompanying figures, also concerns and includes all the features of the appended set of claims. Bracketed references in the claims do not limit the scope thereof, but are merely provided as non-binding examples of the respective features. The claimed features can be applied separately in a given product or a given process, as the case may be, but it is also possible to apply any combination of two or more of such features therein. The invention is not limited to the embodiments and/or the examples that are explicitly mentioned herein, but also encompasses amendments, modifications and practical applications thereof, in particular those that lie within reach of the person skilled in the relevant art.

Claims

1. A drive belt (50) for a continuously variable transmission and comprising a ring stack (8) and a plurality of transverse segments (1) that are mounted in a row along the circumference of the ring stack (8), whereto the transverse segments (1) each define a central opening (5) between a base part (10) and two pillar parts (11) thereof, which pillar parts (11) are respectively provided on a respective side of the base part (11), whereof one pillar part (11-n) is provided with an undercut (7) relative to the other one pillar part (11-b) and whereof a side face (14) of the other one pillar part (11-b) facing the central opening (5) arrives in contact with the ring stack (8) during operation in the transmission, of which transverse segments (1) two types (I, II) are mutually alternating incorporated in the drive belt (50) of which two types (I, II) the respective pillar parts (11-n, 11-b) are provided on mutually opposite sides of the base part (10) thereof, characterized in that, of at least one of the said two transverse segment types (I, II) at least two subtypes (la-lf; lla-llf) are incorporated in the drive belt (50) having contours that are mutually different in at least one design aspect thereof with the exception of, at least, the side faces (14) of the said other one pillar part (11-b) that coincide between the said at least two subtypes (la-lf; lla-llf).

2. The drive belt (50) according to claim 1, characterized in that, of both of the said two transverse segment types (I, II) at least two subtypes (la-lf, lla-llf) are incorporated in the drive belt (50) having contours that are mutually different in at least one design aspect thereof with the exception of, at least, the side faces (14) of the said other one pillar part (11-b) that coincide between the said at least two subtypes (la-lf, lla-llf).

3. The drive belt (50) according to claim 1 or 2, characterized in that, the said at least one different design aspect entails one or more of:

- the base part (10) of the transverse segment (1) having a concave bottom surface (20) versus a straight bottom surface,

- a hole (21, 22) being provided in the base part (10) of the transverse segment (1) versus a solid base part (10),

- the undercut (23) of the said one pillar part (11-n) having a different axial extent, or

- a side face (25) of the undercut (24) of the said one pillar part (11-n) being differently oriented.

4. The drive belt (50) according to claim 1, 2 or 3, characterized in that, the said subtypes (la-lf; lla-llf) of the two transverse segment types (I, II) are arranged in the said row thereof in a non-cyclical ordering.

5. A blanking process for blanking transverse segments (1) for a drive belt (50) for a continuously variable transmission and comprising a ring stack (8) and a plurality of transverse segments (1) that are mounted in a row along the circumference of the ring stack (8), whereto the transverse segments (1) each define a central opening (5) between a base part (10) and two pillar parts (11) thereof, which pillar parts (11) are respectively provided on a respective side of the base part (11), whereof one pillar part (11-n) is provided with an undercut (7) relative to the other one pillar part (11-b) and whereof a side face (14) of the other one pillar part (11-b) facing the central opening (5) arrives in contact with the ring stack (8) during operation in the transmission, characterised in that two or more such transverse segments (1) are blanked simultaneously, whereof the respective pillar parts (11-n, 11-b) are provided on the same side of the base part (10) thereof, characterized in that, these simultaneously blanked transverse segments (1) are mutually different in at least one design aspect thereof with the exception of, at least, the side faces (14) of the said other one pillar part (11-b) that mutually coincide.