AU2009101343A4

AU2009101343A4 - Toothed wheel and drum drive

Info

Publication number: AU2009101343A4
Application number: AU2009101343A
Authority: AU
Inventors: Zili Wu
Original assignee: SEW Eurodrive GmbH and Co KG
Current assignee: SEW Eurodrive GmbH and Co KG
Priority date: 2008-11-03
Filing date: 2009-10-16
Publication date: 2011-02-24
Anticipated expiration: 2017-10-16
Also published as: EP2347148B1; AU2009101343A8; WO2010060505A1; FI2347148T4; EP2347148A1; EP2347148B2

Description

Toothed wheel and drum drive Description The invention concerns a gear and a drum drive. 5 In the case of transmissions driving gear parts are known which are engaged with a further gearing. From US 5 890 814 a drum drive is known, wherein support rings are mounted on 10 the drum at radial distances from it. A further gearing is separately applied. Therefore the object of the invention is to provide a drum, that is greater than the machine tools available for the manufacture of a gearing, in particular gear cutting machines, or the gearing that can be produced with such machines. 15 According to the invention this objective is achieved with a gear having the features of claim 1 and a drum drive having the features of claim 11. The important features of the invention are that it is a gear, composed from 20 geared segments, in particular ring segments, the teeth of which is formed from the teeth of the segments, wherein each adjacent segment is joined by bolts, in particular wherein in the circumferential directions the segments have radially orientated faces at both ends, said faces having drilled holes to accommodate the bolts of the bolted joints, in particular wherein the drilled holes are tangentially 25 orientated. It is an advantage of the invention that the gear can be easily manufactured and its quality can be controlled to a great degree. 30 According to an advantageous configuration the bolted assembly comprises at least two locating bolts and at least two fastening bolts, in particular at least three or four fastening bolts, in particular whereby the fastening bolts are studs. The advantage in this case is that the alignment and the firm joining can be carried out in sequence. 24889791 (GHMatters) P85650AU 2 According to an advantageous configuration the gear is composed of N segments, in particular ring segments, wherein the number N is between 7 and 25. According to an advantageous configuration the gearing of the gear has a module m and 5 each segment, in particular ring segment, has z number of teeth, wherein the product z x m has a value in the range of between 340 mm and 440 mm. The module is in particular between 10 and 100 mm. The advantage in this case is, that a particularly high load and torque can be transmitted. 10 In the case of an advantageous configuration the gear has a module, wherein * in the case of a module of 20 mm each ring segment has between 17 and 22 teeth, 15 " in the case of a module of 25 mm each ring segment has between 13 and 17 teeth, " in the case of a module of 30 mm each ring segment has between 11 and 14 20 teeth, e in the case of a module of 40 mm each ring segment has between 8 and 10 teeth. 25 The advantage in this case is that a particularly high load and torque can be transmitted. According to an advantageous configuration of the ring segment is, that the ring segment has a protrusion, in particular a shoulder, extending in the circumferential 30 direction. It is an advantage in this case that a particularly accurate alignment of the segments relative one another is possible. It is also an advantage of the invention, that after assembling the ring segments into a ring the entire ring can be rotated and thus by means of an at least linearly 2488979_1 (GHMatters) P85850 AU 3 deflectable distance measuring means, like a measuring stylus, the radial and/or axial deviations from an ideal value can be determined. In this manner a ring segment that, for example, radially protrudes too far or is radially too deep, can be moved until it is positioned in the tolerated range. The moving is preferably carried 5 out by slightly loosening the fastening bolts and then by means of tapping the ring segment is moved. The fastening bolts are subsequently retightened. According to an advantageous configuration the protrusion is provided radially at a distance that is smaller than the gearing provided on the ring segment, in 10 particular at a radial distance that is smaller than the root circle of the gear. In this case it an advantage that an uninterrupted, by the gearing, rotation of the ring and a determination of the radial deviations is possible. According to an advantageous configuration the teeth are involute teeth. In this 15 case it is an advantage that the teeth can be simply and cost-effectively produced using known machine tools. According to an advantageous configuration the gearing is made from ADI. In this case it is an advantage that a particularly long service life of the teeth can be 20 achieved and, in addition, great forces can be transmitted in very compact spaces, therefore, when compared with the outside diameter of the drum or the outside diameter of the gear, composed by assembling the ring segments, a very small driving gear can be used as part of the gear drive. 25 According to an advantageous configuration the protrusion projects axially from the surrounding surface area of the ring segment. In this case it is an advantage that in this manner not only axial movements but also radial deviations can be determined. The protrusion should be a ground surface, whereby in particular a ground cylindrical body section is to be provided and an axially protruding face. 30 According to an advantageous configuration it has at the end faces, situated in the circumferential direction, tangential drilled holes, i.e. in the circumferential direction, into which in particular fastening bolts can be introduced to join it with a further similar ring segment. In this case it is an advantage that the ring, 2488979_1 (GHMatters) P85850AU 4 composed from ring segments, has a complete gearing that in the region of the transition between the ring segments does not have any significant interrupting regions. 5 According to an advantageous configuration the ring segment has a sword-like shape below the teeth. In this case it is an advantage that a firm carrier-capable support can be joined, that also forms the ring composed from the ring segments. According to an advantageous configuration in the sword-like regions axially 10 extending holes are provided to introduce the fastening bolts, with which the ring segment can be secured on a carrier part, in particular a drum, ring or ring segment. In this case it is an advantage that the ring segment can be executed with few bracings or other reinforcements requiring material, since the shaping for the ring is ensured by the drum or by some other supporting part. Consequently 15 the ring itself does not have to retain its shape. According to an advantageous configuration the ring segment is formed integrally with the teeth, faces and sword-like region. In this case it is an advantage that a stable and secure fastening can be carried out in a simple manner. 20 According to an advantageous configuration the protrusion on an axially projecting surface area and/or on a surface area with a radial normal is so finish machined, that the concentricity can be determined by means of a measuring stylus, in particular to determine the concentricity error, in particular to improve the 25 alignment of the ring segments relative one another. In this case it is an advantage that concentricity error can be determined along the entire circumference of the gear and thus the alignment of the segments relative one another can be detected and corrected. 30 According to an advantageous configuration the protrusion is at a radial distance that is smaller than the teeth provided on the ring segment, in particular at a radial distance smaller than the root circle of the gear. 24889791 (GHMatters) P85650AU 5 According to an advantageous configuration the protrusion projects axially from the surrounding surface area of the ring segment, while the teeth are provided radially outward on the ring segment. In this case it is an advantage that the concentricity error can be carried out a distance from the gearing. 5 According to an advantageous configuration radially below the teeth the ring segment has a sword-like joining area, so that the joining area of the ring segments with one another is at a greater radial distance than the joining area of the ring segments with a part, like the drum or shaft, driven by a gear. In this case 10 it is an advantage that great torques and forces are allowed within the ring segments joined. According to an advantageous configuration the ring segments have a connecting web area connecting the faces, in which area cut-outs are provided to pass 15 through joining bolts that join the ring segment with the part to be driven, so that the joining area of the ring segments with one another and the joining area of the ring segments with the part driven by the gear, like the drum or shaft, overlap at least a common partial radial distance area, therefore are provided in particular essentially radially at the same radial distance. In this case it is an advantage that 20 with little material great strength can be achieved and great torques can be transmitted since they are transmitted, at the same radial distance. According to an advantageous configuration the connecting web area has at least one cut-out, in particular at least one oval cut-out, or, viewed in the axial direction, 25 an asymmetrical and one or more symmetrical cut-outs. In this case it is an advantage particularly in the case of an oval cut-out that great stability can be achieved with small mass. According to an advantageous configuration the connecting web area has a 30 plurality of symmetrical cut-outs provided successively in the circumferential direction, that are separated by essentially radially extending intermediate webs, while in the intermediate webs axially extending holes are provided for fastening on the part to be driven. In this case it is an advantage that each intermediate web has to transmit only a small portion of the torque and despite this with little 2488979_1 (GHMatters) P85650 AU 6 material a great overall torque can be transmitted if many intermediate webs and cut-outs are provided in each segment. According to an advantageous configuration the ring segment is formed integrally 5 with the teeth, faces and sword-like region, in particular the connecting web area. In this case it is an advantage that a stable supporting a ring segment can be produced with a little material. Important features of the drum drive are that it comprises a drum and a driving 10 gearing part, while on the external circumference of the drum ring segments are provided, while the ring segments have teeth, while the driving gearing part is engaged by the teeth and the drum is at least partially mounted over the gearing part. 15 It is important in this case that the weight of the drum can be extended over the driving gearing part. This is particularly facilitated by the use of ADI as material for the gearing. This makes the supporting capacity so great, that the entire mounting of the drum will be possible. 20 In this case it is an advantage that the gearing can be driven by the driving gearing part. In particular this gearing part can be executed much smaller than the gearing formed from the composed ring segments. The outside diameter of the driving gearing part is at least five times smaller than the outside diameter of the gearing formed from the composed ring segments. In this manner a drum or a 25 corresponding cylindrical object can be driven in a simple manner. The particular advantage of using the ring segments is also that the machine tool used for the manufacture of the gearing can be correspondingly small, in particular the machine tool is smaller than the gearing formed from the composed ring segments. Consequently, by joining with the drum the drum can be used as 30 supporting and form-shaping part. For this reason the ring segments can be also manufactured with thin walls with fewer reinforcements and braces. Even weight saving cut-outs may be provided. 2488979_1 (GHMatters) P85450.AU 7 At the same time the shaping depends on the drum and great temperature fluctuations are to be avoided, since due to the rigid joining of the ring segments with the drum the change of the shape also affects the gearing formed by the combined ring segments. 5 According to an advantageous configuration the driving gearing part is engaged by the composed gearing formed by the teeth of the ring segments. In this case it is an advantage that a rotating movement of a large heavy part is made possible without it having a continuous interruption-free integrally manufactured gearing. 10 According to an advantageous configuration on the external circumference of the drum at least one first ring or at least ring segments, composed in the circumferential direction and forming a first ring is provided, in particularly joined with the drum by welding. In this case it is an advantage that stresses and 15 vibrations in the circumferential direction are somewhat dampened. According to an advantageous configuration further ring segments are provided, which in the circumferential direction are composed to form a further ring and are joined with the first ring or corresponding ring segments, in particular by welding. 20 In this case it is an advantage that also for the rigid fastening of the gearing formed from the composed ring segments. On the parts provided on the drum can be produced from segments. According to an advantageous configuration the ring segments having a gearing 25 are joined with the first and/or further ring segments, in particular in a force-locked manner, in particular by bolts. In this case it is an advantage that the parts with teeth can be fastened on the ring segments, which on the drum surface radially protrude and consequently represent a less complicated fastening possibility for the axially aligned fastening bolts. On this occasion the ring segments are 30 preferably welded to the surface of the drum. According to an advantageous configuration holes are provided in the ring segments that can be joined, into which bolts are introduced to align the ring segments with one another. In this case it is an advantage that an alignment can 2488979_1 (GHMalters) P85850.AU 8 be simply carried out. The bolts are preferably provided in the holes in such a manner, that a small tolerance range is available for the relative movement of the ring elements. Thus a fine adjustment is possible, by tapping for example, with subsequent tightening of the fastening bolts. 5 According to an advantageous configuration in the sword-like region at least one cut-out is provided to reduce the mass of the ring segment, in particular wherein in the circumferential direction the cut-out is at a distance from the circumferential position of the fastening region, in particular corresponding holes. In this case it is 10 an advantage that axial cut-outs are provided. According to an advantageous configuration further ring segments are provided, which in the circumferential direction are composed into a further ring and are joined with the first ring or corresponding ring segments, in particular by welding. 15 According to an advantageous configuration holes are provided in the ring segments that can be joined, into which bolts are introduced to align the ring segments with one another. 20 According to an advantageous configuration in the sword-like region at least one cut-out is provided to reduce the mass of the ring segment, in particular wherein in the circumferential direction the cut-out is at a distance from the circumferential position of the fastening region, in particular corresponding holes. 25 Further advantages become obvious from the sub-claims. 2488979_1 (GHMatlers) P85850 AU 9 List of reference numerals 1 Ring segment 2 Gear 3 Oval cut-out 20 Holes for locating bolts 21 Holes for fastening bolts 22 Retaining area 23 Connecting web area 30 Holes for aligning 31 Hole 32 Gearing/Teeth 33 Asymmetrical cut-out 34 Symmetrical cut-out 35 Intermediate webs of the connecting web area 40 Shoulder 50 Ring segment 51 Fastening bolt 52 Ring segment 53 Drum 60 Ring segment 61 Fastening bolt 2488979_1 (GHMatters) PB558O.AU 10 In the following the invention is explained based on illustrations: Fig.1 shows an arrangement according to the invention with a plurality of ring segments 1. 5 Fig.2 shows a ring segment 1 in an oblique view. Fig.3 shows a similarly constructed ring segment 1 in side view. 10 Fig.4 shows an associated sectioned view. Fig.5 shows a schematic section through the arrangement, comprising the fastening means on a drum. 15 Fig.6 shows an alternative execution. Fig.7 shows a further large gear, composed from sixteen ring segments 1, wherein each ring segment has 14 teeth. 20 Fig.8 shows a detail of the joint of two ring segments of Fig.7. Fig.1 shows ring segments 1 with external gearing and joined with one another, that are fastened together on a drum to be driven. The ring segments 1 together form a gear, therefore a large gear, driven by a smaller gear 2. This gear 2 is 25 connected by form-locking with a drive shaft of a transmission (not illustrated). Thus an electric motor of low capacity, provided on the driving side of the transmission, is able to drive the large gear. The ring segments are joined by means of bolts with the ring segments adjacent 30 to them in the circumferential direction and fastened on the ring segments, which in turn are fastened on the drum. For the joining of two ring segments 1, adjacent in the circumferential direction, locating bolts are provided, whereby these serve for their alignment, and four fastening bolts, with which the ring segments to be joined in the circumferential direction are pressed together. 2488979_1 (GHMatters) P8585O.AU 11 A ring segment 1 is illustrated in detail in Fig.2. On both end regions, provided in the circumferential direction, the ring segment has retaining areas 22, that are provided with drilled holes, into which the locating 5 bolts 20 and the joining bolts 21 [sic], positioned radially lower, respectively, can be introduced. Both retaining areas are joined with one another by means of a connecting web area 23. Each ring segment 1 has an oval cut-out 3 in the connecting web area 23, that 10 has a mass-reducing effect without considerably influencing the strength and stability of the ring segment 1. For this purpose the oval cut-out of each ring segment 1 is longer in the circumferential direction than in the radial direction. The geared region is provided with the teeth 32 radially outside, adjacent to the 15 retaining areas 22 and the connecting web area 23. The ring segment is preferably manufactured in one piece from ADI or GGG-steel casting. The connecting web area 23 protrudes sword-like radially inwards. This protruding area enables a joining with the drum to be driven. For this purpose preferably 20 joining bolts 4 and corresponding holes (not illustrated in Fig.2) are provided in the axial direction in the protruding area and in the drum. The joining with the drum is carried out by means of the axially orientated joining bolts 4 below that radial distance, which is used for joining the ring segments 1 25 with one another. Fig.3 shows an enlarged illustration of a further similar ring segment 1, wherein the gearing 32 is provided on the external edge. In addition, holes 30 for alignment and holes 31 for fastening are shown. By using ADI or GGG-steel 30 casting, respectively, for material, due to the settling of the bolts the loss of pre tensioning force is smaller and consequently the joining can be more securely affected. This because now greater forces are possible. A particularly advantageous effect is in this case that when compared with other hardened steels, ADI or GGG-steel casting are more elastic and harder. 2488979_1 (GHMatter) P8S55AU 12 In contrast to the execution shown in Fig.2, the ring segment 1 has in this case more cut-outs (33, 34), provided successively in the circumferential direction. Viewed in the circumferential direction, at the front and the rear an asymmetrical cut-out 33 and between them symmetrical cut-outs 34, are provided. Thus holes 5 30 for aligning can be provided without considerably influencing the stability. The connecting web area 35 is not completely illustrated. The axially extending holes 31, provided in the connecting web area 35, are intended for axially orientated joining bolts for joining with the drum. 10 Thus the joining with the drum on approximately at the same radial distance enables the joining of the ring segments 1 with one another. As it is shown in Fig.4, the ring segments 1 have a shoulder 40 extending in the 15 circumferential direction, so that after assembling the ring segments 1 a shoulder is formed in the circumferential direction of the large gear formed in this manner, on which shoulder a measuring means, for example a measuring stylus, can be provided, that during the rotation of the gear is deflected only due to deviations from the circular shape caused by manufacture or deviations caused by incorrect 20 alignments of the ring segments 1. For this purpose surfaces, bordering the shoulder, ground or machined precisely by other means, are provided. Therefore in particular a precisely machined annular surface, bordering the shoulder, is provided, on which the measuring stylus detects deviations in the radial direction, and a further precisely machined annular surface, bordering the shoulder, on 25 which the measuring stylus detects the deviations in the axial direction. Thus after loosening the fastening bolts, which join the ring segments 1, an adjustment is possible, for example by moving them by means of tapping. After adjustment the fastening bolts are again tightened. The basic alignment of the ring 30 segments relative one another is, however, achieved by the locating bolts provided in the holes 20. Compared with steel, ADI is a very hard material, but it is elastic. 2488979_1 (GHMattes) P85850.AU 13 Because not only the geared area, but also the entire ring segment is manufactured from ADI, by means of the fastening bolts, provided in the holes 21, a slight elastic deformation of the retaining area of the ring segments can be achieved and consequently the distance of the centres of the ring segments can 5 be altered relative one another. Thus an equalisation or at least a reduction of incorrect tolerances can be achieved by further tightening the fastening bolts. Thus even deviations from a few pm up to 10 pm can be equalised. The production of the gearing 32 of the ring segments relative the face of the ring 10 segments is carried out as accurately as possible. In this manner a gear can be manufactured by aligning and joining ring segments, the gearing of which in the joining area of the ring segments has possibly small deviations from an ideal gearing. 15 The gearing is preferably an involute gearing. Fig.5 shows an example of a possible fastening for the ring segments 1 on the drum. In this case on the external circumference of the drum 53 two ring segments 52 are provided, welded parallel to one another, to which, in turn, two 20 further parallel ring segments 50 are welded. By means of the fastening bolts 51, passing through the drilled holes in the ring segment 50, the ring segment 50 is bolted on, while on that end of the bolt which is opposite the head of the bolt, a nut is provided. 25 At the same time the ring segments 51 are at distance from one another that is smaller than that between the ring segments 52 and at a greater radial distance than the ring segments 52. In this manner the possibility of deflection of the ring segments 50 in the axial direction of the ring segments is improved during fastening of the ring segments 1. 30 Fig.6 shows an alternative embodiment. In this case again a pair of parallel ring segments 60 are provided on the external circumference of the drum 53, joined by welding with the drum 53. The ring segment 1 is bolted by means of fastening bolts 61. 24589791 (GHMatterS) PB50AU 14 Two ring segments 1, adjacent in the circumferential direction, are joined on the faces visible in Fig.6, through the holes (20, 21). For this purpose the holes 20 are intended for locating bolts and the holes 21 for fastening bolts. In this case the locating bolts fill in the holes 20 completely, so that the relative alignment of the 5 ring segments relative one another is carried out by aligning the holes 20 with the locating bolts inserted into them. The four fastening bolts do not completely fill the holes 21, due to which there is a clearance present in these holes. By using ADI or GGG-steel casting, a strong tightening force by the fastening bolts is allowed. The loss of the pre-tensioning force is reduced by the settling of the bolts and thus 10 a stable joint is achieved. In particular, however, the influencing of the distances of the centres of gravity of the ring segments 1 relative one another can be carried out, in particular within some pm or even some 10 pm. The aim of the execution according to Fig.7 is the provision of a segmented large 15 gear of a new type, that is easy to produce and the quality of which can be controlled to a great extent. The new segmented large gear comprises 7 to 25 segments, whereby the adjacent segments are joined with one another by means of bolts. Fig.7 shows an 20 example with 16 segments, while each segment has 14 teeth. In Fig.8 the joining area of two segments is illustrated in detail. In this case the segments have on both their end regions, provided in the circumferential direction, radially orientated faces that have drilled holes to accommodate the bolts of the bolted joint, in particular when the drilled holes are tangentially orientated. In this case in the 25 drilled holes 20, situated at a greater radial distance, a locating bolt for the purpose of alignment, and in the drilled holes 21, situated further inward, a fastening bolt each is provided. Therefore the bolts are tangentially orientated. The invention has the following advantages: 30 1. Simple casting operation; since each individual segment is very small, the quality of the castings can be better controlled. Cooling cracks can be avoided. 2488979_1 (GHMatts) P85650 AU 15 2. No special machining equipment is required; since the individual segments are relatively small, as a rule, existing equipment can be used. The manufacturer does not have to procure further special equipment for this purpose, so that production costs can be reduced. 5 3. More convenient transport: the segments, individually and together, can be simply moved in the factory and at the venue of application of this gear. No special vehicle is required for their transport. A segmented large gear can be easily transported in a standard container. 10 4. The quality can be better controlled: because the individual segments are very small, possible rejects can be immediately removed without causing large expenses. In addition the large gear is combined only from those segments which are free of cooling cracks and other defects. 15 5. Simplified exchange of segments: if an individual segment is defective due to an unexpected reason, it can be removed from the large gear without any problem and promptly replaced by a new segment, so that the plant concerned can be operational as soon as possible. 20 6. Quick delivery: the large gears are produced first as individual segments and then assembled into a large gear module. This accelerates the production and guarantees a quick and reliable delivery of the products. 25 The basis of ADI casting materials (austempered ductile iron) is cast iron with spherical graphite. The ADI material is produced by multi-stage heat treatment. According to further embodiments according to the invention the ring segments are heat treated. 30 According to further embodiments according to the invention the drum, with its large gear, is mounted on two driving gears, the centrelines of which are aligned parallel with the axis of the drum and extend in a plane that is provided below the drum. In this case both driving gears are provided in a first axial position. If the 2488979_1 (GHMatters) P85650.AU 16 same arrangement, comprising the gear fastened on the drum and two corresponding gears, are arranged in another axial position, even a total mounting of the entire drum is possible. In this case the gears fastened on the drum are executed according to the embodiments of the figures. 5 24889791 (GHMatters) P55650.AU

Claims

1. A driving arrangement, with a driven part, in particular a drum or a shaft, and with a driving gear composed from geared segments, in particular ring 5 segments, the teeth of said gear, in particular the teeth provided on the external circumference, is formed and/or composed from the teeth of the segments, wherein each adjacent, in the circumferential direction, segment is joined by bolts, in particular wherein the segments have radially orientated faces at both ends in the circumferential direction, in particular in the retaining 10 areas 22, said faces having drilled holes to accommodate the bolts of the bolted connection, in particular wherein the drilled holes are tangentially orientated, wherein the end regions are joined by means of a connecting web area, in particular wherein the driving part has a smaller diameter than the driven part. 15

2. A gear according to at least one of the preceding claims, characterised in that the bolted joint comprises at least two locating bolts and at least two fastening bolts, in particular at least three or four fastening bolts, in particular wherein the fastening bolts are studs. 20

3. A gear according to at least one of the preceding claims, characterised in that the gear is composed of N segments, in particular ring segments, wherein the number N is between 7 and 25, and/or that the gearing of the gear has a module m and each segment, in particular ring segment, has z number of 25 teeth, wherein the product z x m has a value in the range of between 340 mm and 440 mm, in particular wherein the module is between 10 and 100 mm.

4. A gear according to at least one of the preceding claims, characterised in that the gear has a module, wherein 30 * in the case of a module of 20 mm each ring segment has between 17 and 22 teeth, * in the case of a module of 25 mm each ring segment has between 13 and 17 teeth, 24889791 (GHMatterS) P85650.AU 18 * in the case of a module of 30 mm each ring segment has between 11 and 14 teeth, e in the case of a module of 40 mm each ring segment has between 8 and 10 teeth. 5

5. A gear according to at least one of the preceding claims, characterised in that the ring segment has a protrusion, in particular a shoulder, extending in the circumferential direction and/or that the protrusion on an axially projecting surface area and/or on a surface area with a radial normal is so finish 10 machined, that the concentricity can be determined by means of a measuring stylus, in particular to determine the concentricity error, in particular to improve the alignment of the ring segments relative one another, and/or that the protrusion is at a radial distance that is smaller than the teeth provided on the ring segment, in particular at a radial distance smaller than the root circle of the 15 gear, and/or that the protrusion projects axially from the surrounding surface area of the ring segment, while the teeth are provided radially outward on the ring segment.

6. A gear according to at least one of the preceding claims, characterised in that 20 the teeth are involute teeth and/or that the gearing is made from ADI or GGG casting.

7. A gear according to at least one of the preceding claims, characterised in that on its end faces, situated in the circumferential direction, it has tangential 25 drilled holes, i.e. in the circumferential direction, into which in particular fastening bolts can be introduced to join it with a further similar ring segment.

8. A gear according to at least one of the preceding claims, characterised in that the ring segment has a sword-like shaped connecting web area below the 30 teeth, so that the connecting web area of the ring segments are at a radial distance that is greater than the connecting web area of the ring segments with a part, like drum or shaft, driven by the gear, or that the ring segment has a connecting web area joining the faces, in which connecting web area cut-outs are provided to pass through joining bolts that join the ring segment with the 2488979_1 (GHMattes) P85650.AU 19 part to be driven, so that the joining area of the ring segments with one another and the joining area of the ring segments with the part driven by the gear, like the drum or shaft, overlap at least a common partial radial distance area, therefore are provided in particular essentially radially at the same radial 5 distance.

9. A gear according to at least one of the preceding claims, characterised in that in the connecting web area axially extending holes are provided to introduce the fastening bolts, with which the ring segment can be secured on a carrier 10 part, in particular a drum, ring or ring segment, and/or that the connecting web area has at least one cut-out, in particular at least one oval cut-out, or, viewed in the axial direction, an asymmetrical and one or more symmetrical cut-outs, and/or that the connecting web area has a plurality of symmetrical cut-outs provided successively in the circumferential direction, that are separated by 15 essentially radially extending intermediate webs, while in the intermediate webs axially extending holes are provided for fastening on the part to be driven.

10. A gear according to at least one of the preceding claims, characterised in that 20 the ring segment is formed integrally with the teeth, faces and sword-like region, in particular connecting web area.

11. A drum drive, comprising a drum and a driving gear part, wherein on the external circumference of the drum ring segments are provided, each of which 25 is fastened on the drum, wherein the ring segments form a gearing of a gear, in particular wherein the gear and/or the ring segments are constructed according to any one of claims 1 to 10, wherein the driving gearing part is engaged by the teeth and the drum is at least partially mounted over the gearing part. 30

12. A drum drive according to claim 11, characterised in that the driving gearing part is engaged by the composed gearing formed by the teeth of the ring segments. 2488979_1 (GHManers) P85650.AU 20

13. A drum drive according to any one of claims 11 or 12, characterised in that on the external circumference of the drum at least one first ring or at least ring segments composed in the circumferential direction and forming a first ring are provided, in particular joined with the drum by welding, and/or that further 5 ring segments are provided that are combined in the circumferential direction to form a further ring and are joined with the first ring or the corresponding ring segments, in particular by welding, and/or that the ring segments having a gearing are joined with the first and/or further ring segments, in particular in a force-locked manner, in particular by bolts. 10

14. A drum drive according to any one of claims 11 or 13, characterised in that holes are provided in the ring segments which can be joined with one another, into which bolts are introduced to align the ring segments with one another.

15 15. A drum drive according to any one of claims 11 or 14, characterised in that in the sword-like region at least one cut-out is provided to reduce the mass of the ring segment, in particular wherein in the circumferential direction the cut-out is at a distance from the circumferential position of the fastening region, in particular corresponding holes. 20 2488979_1 (GHMatters) P85650.AU