EP2074338A1

EP2074338A1 - Bevel friction ring gear mechanism

Info

Publication number: EP2074338A1
Application number: EP07817567A
Authority: EP
Inventors: Werner Brandwitte; Christoph DRÄGER; Ulrich Rohs
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-09-22
Filing date: 2007-09-24
Publication date: 2009-07-01
Also published as: US20090305841A1; BRPI0715241B1; CN101542165A; CN101542165B; EP2434182A1; DE112007002840A5; BRPI0715241A2; JP2010504477A; JP5303789B2; WO2008034438A1; DE102007002581A1; KR20090059137A; US8187142B2

Abstract

In order to absorb loadings on friction faces in bevel friction ring gear mechanisms in an improved manner, the invention proposes a bevel friction ring gear mechanism having at least two friction cones which are arranged spaced apart from one another and a friction ring which is arranged displaceably in said spacing and transits a torque from one of the two friction cones to the other of the two friction cones, wherein at least one friction face varies axially and the axial variation of the friction face has a radius above 0.1 mm in at least two convex regions.

Description

bevel friction ring gearing

The invention relates to conical friction ring gear with at least two mutually spaced friction cones and arranged at this distance along friction surfaces on the Reibkegeln displaceable, a torque of one of the two friction cone on the other of the two friction cones transmitting friction ring, wherein at least one friction surface axially varied.

Such conical friction ring transmissions are well known, for example, from WO 2004/031615 A2, wherein the variation of the friction surface serves to equalize the surface pressure, which otherwise due to the strongly differing tread diameter, in particular with respect to conical friction ring, in which Friction ring encompasses at least one of the cones, also subject to very strong deviations. In this regard, the grooves disclosed in this document have proven particularly useful, which can be introduced in a targeted manner into a surface.

[03] In practice, however, it turns out that surfaces designed in this way wear out severely.

[04] It is therefore an object of the present invention to further develop a generic conical friction ring transmission such that wear of the friction surface is minimized.

[05] The object of the invention is arranged by a conical friction ring gear with at least two spaced apart friction cones and arranged at this distance along friction surfaces on the Reibkegeln, transferring a torque from one of the two friction cone on the other of the two friction cones Friction ring solved in which at least one friction surface varies axially and which is characterized in that the axial variation of the friction surface in at least two convex portions has a radius over 0.1 mm.

[06] Advantageously, the loads of the friction surface by such selected radii are much lower, so that the cone wear much less.

[07] In the present context, the term "convex areas" describes surface areas of the friction surface that are convexly shaped in a section. Accordingly, according to the invention, an axial variation is directed to an axial section in which convex areas are to be formed according to the invention Accordingly, in the context of the present invention, "convex areas" particularly describes those areas of the friction surface which form groove inlets, in particular also rounded groove inlets in the sense of the invention. Not to be covered by these variations of the envelope of the respective cone, such as for the friction ring in terms of its transmission ratio relevant variations of the friction surface, such as deviations from a strictly conical surface by a change in slope of the generatrix.

Since a friction surface is provided by means of the above-explained convex portions, which allows a friction ring to a substantially frictional connection, the present invention just does not detect further known from the prior art continuously variable transmission, in which a forces or torques Transmission does not take place due to a frictional connection between cones and a ring connecting the cone, but are used for the forces or torques transmission form-locking connections that arise between the cones and the ring. Examples with regard to bevel gears in which a force or torque transmission is achieved by means of positive connections, are well known from the prior art. [0002] German Patent DE 825 933 B describes a continuously variable transmission in which a hard rubber ring circulates in a gap between two roughened or grooved cones. It is obvious that the hard rubber ring, which is clamped between the two cones, engages in the grooves of the cones, and thereby a positive connection is achieved by means of the engaging into the individual grooves of the cones hard rubber ring. Thus, this invention differs fundamentally from the prior art, moreover, the problem of preventing a critical surface pressure between mutually rubbing components of a conical-friction ring gear is neither recognized nor described.

[10] The situation is similar in the case of the transmission system described in US Pat. No. 6,908,406 B2, in which an elastic ring is squeezed between two notched cones in such a way that the two cones notched on their surfaces are in operative contact by means of the crimped ring , However, a transmission of forces or torques between the components corresponding to one another does not take place on the basis of frictional connections but essentially on account of form-fit connections between the components. Thus, US Pat. No. 6,908,406 B2 likewise does not disclose a conical-friction-ring transmission in which a transmission of forces or torques between a friction ring and friction cones takes place frictionally.

[11] A positive connection for the transmission of forces or torques between two bevel gears also makes use of the continuously variable transmission disclosed in DE 195 07 525 A1, in which a corresponding operative contact between the two bevel gears is achieved by means of a self-contained helical spring loop , In particular, a force transmission with respect to bevel gears caused by friction elements should now be achieved here by means of bevel gears and by means of helical spring loops engaging in the bevel gears. Since the bevel gears of the continuously variable transmission described there with their teeth form-fitting with the Coil spring loops change act, the conical friction ring according to the invention, however, provides a friction connection between the friction ring and the friction cones, also the disclosed in the published patent DE 195 07 525 Al object does not affect the present conical friction ring gear.

Another infinitely adjustable bevel gear is known from the patent US 6,139,465, in which by means of a clamped between two rotating cones ring, the two cones are positively connected with each other. In order to ensure or reinforce this positive connection between the ring and the cones, the cones are additionally equipped with columns in the longitudinal direction on their surfaces. Again, there can be no talk of a conical friction ring, since parts of the ring shown there engages in the surface provided with columns at least one of the cone.

Another continuously variable transmission with similarly shaped cones is described in US Pat. No. 6,955,624 B2. However, here is a circulating belt is not clamped between two cones of the continuously variable transmission. Rather, the rotating belt is tensioned by means of the two cones, in which the belt spans the two cones. In order to transmit forces or torques between the individual transmission components, ie belts and cones, substantially slip-free, the conical surfaces are provided with longitudinal grooves and the belt surface with transverse grooves, so that the rotating belt engage particularly well in the grooved O- surfaces of the two cones can and thereby a secure positive connection is achieved.

Also with regard to the documents FR 1.375.048 and FR 1.386.314 continuously variable bevel gears are described, the friction surfaces are grooved so that between two spaced-apart cones, an elastic belt are squeezed and the squeezed belt particularly intimately in grooves of the conical surface can intervene, so that a slip-free form-fitting connection between the cones and the elastic belt is made. Except for a rotational body example shown in FIG. 10 of the last-mentioned French publication, all rotational bodies further shown there are equipped with continuously adjustable transmissions with longitudinal slots which extend in the longitudinal extent along the axis of rotation of the rotational bodies. The rotary bodies shown in FIG. 10, however, comprise circumferential gaps and teeth into which a toothed belt can engage, in order to achieve a good positive engagement with the rotary bodies. However, a transmission of forces and torques between the belt and the cylindrical or conical rotatable bodies which can be formed as a result of a frictional connection is naturally ruled out.

For all of the above reasons, all illustrated continuously variable transmissions are not conical friction ring transmissions in the sense of the present invention, in which a transmission of forces or torques is achieved only by means of frictionally engaged connections. Because of the form-fitting connections described therein, it is not just conical-friction-ring transmissions which are characterized in that a frictional connection can form between a friction ring and friction cones. In this case, in particular a fluidic friction connection can be formed between the friction ring and the friction cones. In this context, a traction and / or a cooling fluid can be arranged in particular between the friction ring and the friction cones in a proper operating state, so that the respective surfaces are in direct contact only in special operating states, for example in start-up or standstill situations.

Particularly in the case of a fluidic frictional connection by means of traction or cooling fluids between the friction ring and the friction cones, the convex regions according to the invention are advantageous, since the fluid is partially displaced by the convex regions, as a result of which the surface pressure can be suitably adapted. [17] Another particularly preferred embodiment provides that the friction surface has radial circumferential grooves for forming an axial variation. In particular, with such on a friction cone radially encircling grooves succeeds structurally simple to vary a friction surface in your axial longitudinal extent almost arbitrarily.

[18] Structurally simple such an axial surface variation can be achieved if the friction surface for forming an axial variation radially encircling grooves having differently shaped groove depths and / or groove widths.

[19] Depending on the design of the friction ring / friction cone connection, the axial variation of the friction surface in the convex areas may have a radius of more than 0.5 mm, preferably more than 1 mm. As a result, with sufficient slot sharpness, the load on the groove inlets can advantageously be further reduced.

It is understood that combinations of different axial variations can also be realized on a friction surface of only one of the two cones.

[21] Also, the area of the friction surface which serves to realize a first speed range can have substantially smaller radii in its convex portions than is the case in regions of the friction surface which form a middle speed range or the highest speed range.

[22] 'In order to obtain even more favorable stress curves within the cone material in concave areas of the friction surface and to be able to realize optimal transmission ratios, in particular when using a traction or cooling fluid, it is advantageous if the axial variation of the friction surface in concave areas Radius over 0.01 mm, preferably over 0.05 mm. It is understood that such a configuration concave area in the friction surface is also advantageous independently of the other features of the present invention. [23] Concave areas on a friction surface are realized, for example, by rounded groove surfaces.

In addition, the object of the invention is also arranged by a conical friction ring gear with at least two spaced cones and arranged at this distance along friction surfaces on the Reibkegeln displaceable, a torque of one of the two cones on the other of the two cones transmitting friction ring in which at least one friction surface varies axially and which is characterized in that the axial variation of the friction surface in at least two convex regions has a radius over one hundredth of the width B of the friction ring.

Although it has been shown that a local consideration of the friction surface in terms of convex and concave areas already bring considerable advantages over the friction surfaces of the prior art. However, it is particularly advantageous if the radii of the convex or concave regions of the friction surface are also adapted to the conditions of the friction ring used, in particular to the width of the friction ring used.

This is partly due to the fact that the friction ring caused by the stresses on the friction surface, especially when a traction and / or cooling fluid is used.

A related embodiment provides that the axial variation of the friction surface in the convex areas has a radius over five hundredths, preferably over one-tenth, of the width of the friction ring.

[28] For the reasons already explained above, it is also advantageous if the axial variation of the friction surface in concave regions has a radius over one thousandths of a width, preferably over five hundredths, of the width of the friction ring Accordingly, independently of the other features of the present invention is inventive.

By not too low radii in concave areas beyond the uniformity of torque transmission can be increased with respect to variations in the thickness of the traction fluid or other medium between the friction ring and cone.

In addition to the design of the radii of the convex or concave areas, it is advantageous if the axial areas between two grooves are chosen to be sufficiently solid, since these form the actually viable area of the friction surface. In this context, at least in axial regions with medium and / or high cone diameter, the grooves can be spaced apart from one another less than one third of the width of the friction ring. By limiting the groove spacing follows a smoother running under load changes. It is understood that the groove distances explained above are also advantageous independently of the other features of the present invention for generic conical friction ring gears.

[31] It should be noted at this point that, when choosing the ratios between groove depths and groove widths on the one hand and a friction ring width, on the other hand, it should ideally be ensured that, with regard to a characteristic stress distribution in the previously described Hertzian pressure, a first stress ellipse of a first stress ellipse convex portion and another voltage ellipse of another by a groove thereof separated and adjacent convex portion do not converge in the groove bottom of the groove. Thus, unwanted voltage peaks in the region of a groove, in particular a groove bottom, can be prevented, whereby the wear of a friction surface can be further reduced. Furthermore, it should be striven that the stress ellipses are chosen as large as possible, so that occurring stresses distributed over a large area and thus can be introduced into a Reibkegelwerkstoff compatible.

Moreover, it is advantageous if the friction surface has radially extending elevations for forming an axial variation. Even by means of such radial circumferential elevations a friction surface can be easily varied axially in design terms.

A structurally particularly preferred embodiment provides that radially encircling elevations of the friction surface are formed by convex regions of the friction surface. In particular, in such an embodiment, the convex areas correspondingly rotate radially on a friction surface.

[35] A particularly advantageous interplay between such circumferential convex areas and the circumferential grooves may result if a respective elevation of the friction surface forming a convex area is arranged between two grooves of the friction surface. By such an interplay between the elevations and the grooves, a friction surface can be made particularly rich in variation.

[36] Advantageously, grooves and elevations on the friction surface form a groove profile of the friction surface, which varies axially. On a groove profile of this type, a friction ring can rub off in a particularly wear-resistant manner and with suitably selected changes in the surface pressure.

[37] In this case, it is advantageous if the elevations of the groove profile form peaks of the friction surface, wherein these wave peaks can advantageously be designed as convex regions with a radius of over 0.1 millimeter.

[38] A further particularly advantageous embodiment of the present invention provides that the friction ring in interaction with a friction cone always covers at least two or more elevations of one of the friction surfaces. Covered the Friction ring at least two or more surveys, the risk is almost excluded that the friction ring can tip into an existing groove or runs restless. Advantageously, this can also prevent that a convex region of the friction surface is subjected to extremely unfavorable, which would result in increased wear of the friction surface.

A particularly effective measure to ensure the smoothness between the friction ring and one of the friction surfaces with increasing Reibkegeldurchmesser, can be seen therein, as the width of the wave crests decreases with increasing groove width.

[40] Further advantages, objects and characteristics of the present invention will be explained with reference to the following description of the appended drawing, in which a construction of a conical friction-ring transmission as well as exemplarily differently designed surfaces are shown.

[41] It shows

FIG. 1 schematically shows an arrangement of a first cone, a second cone and a friction ring,

2 shows schematically the design of a friction surface in a region for realizing a low gear of a transmission,

FIG. 3 schematically shows the design of a friction surface in a region for realizing a middle gear range of a transmission,

4 shows schematically the design of a friction surface in a region for realizing a highest gear range of a transmission, and

Figure 5 schematically shows an input cone with three axial surface variations for a conical friction ring gear.

The arrangement 1 shown in Figure 1 shows the main components of a conical-friction ring transmission comprising a first cone 2, a second cone 3 and a The first cone 2 encompassing friction ring 4. The conical friction ring 4 in the present case has a width B. Both cones 2 and 3 are spaced apart by a distance 5, wherein the cone 2 rotates about a rotation axis 6 and the cone 3 about a rotation axis 7. In order to change the transmission ratio of the conical-friction-ring transmission, the friction ring 4 is displaced axially relative to the cones 2 and 3 according to the double arrow 8 along the axes of rotation 6, 7 and thus also axially to the cones 2, 3. In this case, the portion 9 of the friction ring 4 which is in direct contact with the cones 2, 3 moves accordingly within the gap 5 according to the direction of movement 8.

In order to make the power transmission between the friction ring 4 and the cones 2, 3 as well as the loads on a friction surface 10 of the first cone 2 and on the friction surface 11 of the second cone 3 as low as possible, vary the friction surfaces 10, 11 along the axial Longitudinal extent 12 of both cones 2, 3, so that this results in an axial variation of the friction surfaces 10, 11 results.

[44] By way of example, the said axial variation is described below with reference to FIGS. 2 to 4.

In this case, the surface region 13 illustrated in FIG. 2 shows a friction surface 10, 11 of the conical-friction ring transmission from FIG. 1 in a first or very low gear range. The surface region 14 from FIG. 3 is a friction surface 10, 11 in a central passage region, whereas the surface region 15 according to FIG. 4 represents a highest transition region of a friction surface 10, 11.

[46] The surface area 13 essentially has grooves (not visible here for reasons of drawing) with a very small depth. The resulting wave crests have a radius of R34.08 (the radius R is in mm) or R33 and have a distance of 2.2 mm from each other. The distance is in this embodiment between a first vertex (not explicitly here plotted) of a first wave crest and a second crest of a second wave crest.

[47] Grooves 16 are already more pronounced in the surface region 14. Wave crests 17 (numbered here only as an example) are also 2.2 mm apart. In the surface region 14, the grooves 16 have a depth 18 of 0.17 mm and their rounded groove bottom 19 have a radius R0.39. The wave crests 17 have a width 20 of about 1.4 mm, wherein they have rounded Nuteinläufe 21, which have a radius R13,2.

[48] The surface area 15 comprises grooves 25 with rounded groove bottoms 26 with values R0.6 and a groove depth 27 of 0.28 mm. Between the individual grooves 25 extend wave peaks 28, which are also spaced 2.2 mm apart. The wave crests here have a radius R5,8 and a width 29 of 1 mm, which extend from a rounded groove inlet to an adjacent rounded groove inlet.

Due to the surface configured in this way, the ring on the one hand runs much quieter and can transmit a relatively high torque with justifiable contact forces. Also, the life of the friction surface is significantly extended over known friction surfaces.

The friction cone 110 shown in FIG. 5 is an input friction cone 130 of a conical-friction ring transmission not shown here in detail, which can rotate about an axis of rotation 106 of a drive shaft of the conical-friction-ring transmission not shown here.

[51] The input friction cone 130 is designed as a truncated cone 131 with a first edge region 132 and a second edge region 133. The input friction cone 130 is further provided with a friction surface 110 that varies along the axial longitudinal extent 112 of the input friction cone 130. For this purpose, the friction surface 110 is roughly divided into three friction surface variations 135, 136 and 137. [52] The first friction surface variation 135 forms a first gear range 138, in which a friction ring (not shown explicitly here, but see FIG. 1, reference numeral 4) is located when the conical friction ring transmission is switched, for example, into a starting situation of a vehicle.

[53] The second friction surface variation 136 is followed by a middle gear region 139 at the first gear region 138, and then, with the third friction surface Variation 137, a highest gear region 140.

Starting from the highest gear range 140 and viewing the third Reibflächenvariation 137 can be seen with respect to a detailed view 141 of the third Reibflächenvariation 137 grooves 125 alternately with wave peaks 128, on the one hand radially encircling the Eingangsreibkegel 130 and on the other hand axially adjacent to each other along the axial longitudinal extent 112 of the input friction cone 130 are arranged.

The wave peaks 128 are formed by elevations 142, which also form convex areas 143 at the input cone 130 with a radius C3. In the area of the third friction surface variation 137, the wave peaks 128 have a width (b) 129 which can be selected as a function of the desired surface pressure between the friction ring and the friction surface 110.

[56] The friction ring mentioned here has a width (a) 144 which is chosen so that the friction ring is always in contact with two wave crests 128 and the friction ring is not in danger of tipping into one of the grooves 125 and thereby the convex portions 143, in particular groove slots 121, damage.

By means of a groove depth 127, the groove volume can be structurally simply varied, which in turn allows the amount of traction fluid which is present between the friction ring and the input friction cone 130 to be varied. A radius in the region of groove bottoms 126 is selected in this exemplary embodiment as a function of the ring width (a) 144, the radius in the region of the groove bottoms 126 corresponding to approximately one third of the friction ring width (a) 144.

If the second friction surface variation 136 of the second gear region 139 of the input friction cone 130 is considered in a further detail view 150, it can be seen well that the grooves 116 running around the friction surface 110 have, first, a smaller groove depth 118 and, secondly, a smaller radius as the radii of the groove bases 126 have on the third Reibflächenvariation 137.

[60] In this embodiment, the radius in the region of the groove bottoms 119 is one fifth of the friction ring width (a) 144.

The grooves 116 also alternate in the region of the second friction surface variation 136 with corresponding circumferential wave crests 117, which are formed by further elevations 151 rotating on the input friction surface 110. The wave crests 117 have a slightly greater width (b) 120 than the crests 128 of the third friction surface variation 137 in the region of the second friction surface variation 136. Further convex regions 153 on the friction surface 110 of the input friction cone 130 are formed by means of the elevations 151 and the wave crests 117 formed thereby provided. These further convex portions 153 have a radius C2, which can be chosen as explained below.

By means of the further convex regions 153 thus formed, it is immediately possible to provide rounded groove inlets 121, with which the wave peaks 117 can be rounded off into the described groove bottoms 119.

[63] With regard to the first friction surface variation 135, the friction surface 110 has graphically no circumferential grooves that can be represented meaningfully, which is why these grooves are not numbered either (see third detail view 161). These circumferential grooves in the region of the first friction surface variation 135 have only a very small depth, which is substantially smaller than the groove depths 118 and 127. With these grooves, alternating wave peaks (also not numbered here) are in the area of the first friction surface variation 135 a radius Cl on.

The radii C 1, C 2, C 3 of all wave crests 117, 128 of the friction surface 110 are presently dependent on the forces or torques to be transmitted, the friction cones / friction ring geometries used and the permissible surface pressures which exist between the friction ring and the friction surface 110 exist, selected.

[66] The widths (b) of the wave crests can also be selected from the surface pressure or from the contact surface to be provided between the friction ring and the friction surface 110.

[67] The ring width (a) 144 of the friction ring can be chosen according to the desired application, however, the ring width (a) 144 should cover at least two of the wave crests, thus avoiding the risk of the friction ring creeping in, especially in one of the larger ones circumferential grooves 116, 125 to prevent.

LIST OF REFERENCE NUMBERS

1 arrangement 116 grooves

2 first friction cone 117 peaks

3 second friction cone 118 groove depth

4 encompassing friction ring 35 119 groove bases

5 distance 120 wave width

6 first rotation axis 121 groove inlets

7 second rotation axis 125 grooves

8 Direction of movement 126 Slot reasons

9 section 40 127 groove depths

10 first friction surface 128 peaks

11 second friction surface 129 shaft widths

12 axial longitudinal extension 130 input friction cone

13 first surface area 131 truncated cone

14 second surface area 45 132 first edge area

15 third surface area 133 second edge area

16 grooves 135 first friction surface variation

17 wave peaks 136 second friction surface variation

18 groove depth 137 third friction surface variation

19 groove bases 50 138 first gear area

20 width 139 second passage area

21 groove inlets 140 highest gear range

25 grooves 141 first detailed view

26 groove surfaces 142 surveys

27 groove depth 55 143 convex areas

28 peaks 144 friction ring width

29 width 151 more detail view

102 first friction cone 152 further elevations

106 axis of rotation 153 further convex areas

110 friction surface 60 161 third detail view

112 axial longitudinal extent

Claims

claims:

1. A conical friction ring transmission with at least two spaced-apart friction cones (2, 3, 102) and with a spacing (5) along friction surfaces (10, 11, 110) arranged displaceably on the friction cones (2, 3; , a torque of one of the two friction cone (2, 3, 102) on the other of the two friction cones (2, 3, 102) transmitting friction ring (4), wherein at least one friction surface varies axially, characterized in that the axial variation of the friction surface (10, 11; 110) has a radius (C1, C2, C3) over 0.1 mm in at least two convex areas (143, 153).

2. conical friction ring transmission according to claim 1, characterized in that the axial variation of the friction surface (10, 11, 110) in the two convex portions (143, 153) has a radius (Cl, C2, C3) over 0.5 mm, preferably over 1 mm.

3. conical friction ring transmission according to claim 1 or 2, characterized in that the axial variation of the friction surface (10, 11) in at least two concave areas (19, 26, 119, 126) has a radius greater than 0.01 mm, preferably greater than 0.05 mm, has.

4. conical friction ring gear, in particular also according to one of the preceding claims, with at least two spaced-apart friction cones (2, 3, 102) and one in this distance (5) along friction surfaces (10, 11, 110) on the friction cones (2, 3, 102) displaceably arranged, a torque of one of the two friction cone (2, 3, 102) on the other of the two friction cone (2, 3, 102) transmitting friction ring (4), wherein at least one friction surface (10, 11; axially varied, characterized in that the axial variation of the friction surface (10, 11, 110) in at least two convex portions (19, 26, 119, 126) a radius (Cl, C2, C3) more than one-hundredth of the width (B; a, 144) of the friction ring (4).

5. conical friction ring transmission according to one of the preceding claims, characterized in that the axial variation of the friction surface (10, 11, 110) in the convex areas (143, 153) has a radius (Cl, C2, C3) more than five hundredths, preferably more than one tenth of the width (B; a, 144) of the friction ring (4).

6. Conical friction ring transmission according to one of the preceding claims, characterized in that the axial variation of the friction surface (10, 11, 110) in at least two concave areas (19, 26, 119, 126) has a radius of one thousandth, preferably more than five Hundredth of a width (B; a 144) of the friction ring (4).

7. conical friction ring transmission according to one of the preceding claims, characterized in that the convex portions (143, 153) between two ends (132, 133) of a Reibkegels (2, 3, 102) are arranged.

8. conical friction ring transmission according to one of the preceding claims, characterized in that the convex portions (143, 153) in force and / or torque transmission areas of the friction cone (2, 3, 102) are arranged.

9. Conical friction ring transmission according to one of the preceding claims, characterized in that the friction surface (10, 11, 110) for forming an axial variation (135, 136, 137) radially encircling grooves (16, 25, 116, 125).

10. coned-friction-ring transmission according to one of the preceding claims, characterized in that the friction surface (10, 11, 110) for forming an axial variation (135, 136, 137) radially recirculating grooves (16, 25, 116, 125) with different loan having trained groove depths (18, 27, 118, 127) and / or groove widths.

11. Conical friction ring transmission according to one of the preceding claims, characterized in that at least in axial regions (14; 15; 138, 139, 140) with medium and / or high tapered diameter (16; 25; 116, 125) less than one third of the Width (B, a, 144) of the friction ring (4) are spaced apart.

12. conical friction ring transmission according to one of the preceding claims, characterized in that a circumferential groove (16, 25; 116, 125) of a friction surface (10, 11, 110) of two convex portions (143, 153) is limited.

13. Conical friction-ring transmission according to one of the preceding claims, characterized in that the friction surface (10, 11, 110) has radially extending elevations (142, 152) for forming an axial variation (135, 136, 137).

14. Conical friction ring transmission according to one of the preceding claims, characterized in that radially encircling elevations (142, 152) of the friction surface (10, 11, 110) of convex areas (143, 153) of the friction surface (10, 11, 110) are formed.

15. Conical friction ring transmission according to one of the preceding claims, characterized in that a respective convex portion (143, 153) forming elevation (142, 152) of the friction surface (10, 11, 110) between two grooves (16, 25, 116, 125 ) of the friction surface (10, 11, 110) is arranged.

16. conical friction ring transmission according to one of the preceding claims, characterized in that grooves (16, 25; 116, 125) and elevations (142, 152) on the friction surface (10, 11, 110) a groove profile of the friction surface (10, 11; ), which varies axially.

17. conical friction ring transmission according to claim 15, characterized in that the elevations (142, 152) of the groove profile wave crests (17, 28, 117, 128) of the friction surface (10, 11, 110) form.

18. conical friction-ring transmission according to one of the preceding claims, characterized in that the friction ring (4) in interaction with a friction cone (2,

3; 102) always covers at least two or more elevations (142, 152) of one of the friction surfaces (10, 11, 110).

19. conical friction ring transmission according to one of the preceding claims, characterized in that with increasing groove width, the width (120, 129) of the wave crests (17, 28, 117, 128) is reduced.

20. Conical friction ring transmission according to one of the preceding claims, characterized in that between the friction ring (4) and the friction cones (2, 3, 102) is substantially a friction connection, preferably only a fluidic friction connection.

21. Conical friction-ring transmission according to one of the preceding claims, characterized in that a traction and / or a cooling fluid is arranged between the friction ring (4) and the friction cones (2, 3, 102) in an operating state.