Planetary gear system for a gas turbine engine

Planetary gear system for a gas turbine engine

Abstract 
A planetary gear drive for use in gas turbine engine is provided including a gearbox housing connected to the motor housing, and a ring gear fixed to the interior of the gearbox housing in a cavity defined therein. A first stage planetary gear set is provided in the housing and including a first sun gear coupled to an engine output shaft, and the first planetary gear carrier is rotatably mounted in the housing. First planetary pinion gears are supported by the first bearing and gear mesh with the first sun gear and the ring gear. A second planetary gear stage is provided within the housing and comprising a second gear Sun Along with the first planetary carrier. The second planetary gear set includes a second stage planet carrier coupled to a propeller shaft. The second carrier supports planetary pinion gears meshing with the ring gear and the second gear weapon. The first or second planetary gear carriers can be redeemed for a similar carrier with planetary pinion gear arrangement effective to provide reverse rotation of the propeller shaft.Description 
Background of the Invention1. Field of the InventionThe present invention relates to a planetary gear system, and more particularly to a planetary gear system is used in gas turbine engines.Dos. Description of the Prior Art 
In the field of propulsion propeller aircraft gas turbine and specifically which use two or more motors, is

desirable in some aircraft propellers on each side of the fuselage rotating in opposite directions. Since the turbine engine has a standard rotation direction, which is necessary for those applications to provide different gear reduction transmissions to a specific pair of gas turbine engines used on the same aircraft. Often, this means that the turbine engine has a reverse transmission can have a gearbox that is heavier than the standard rotation transmission in the other motor. Moreover, the gear ratios are usually different and thus the rotational speed of each motor is different. Since the transmission of each motor in a pair in a plane is of a different design, the reliability of the transmission may be different, requiring different parts, etc.As can be seen, the standard rotational requirements identical motor reverse rotation transmission is used for feeding a single aircraft propeller requires a substantial inventory since transmissions are intended to be mounted in the manufacturing plant instead of the field.Furthermore, each of the aircraft engines must be regulated independently in the light of the difference in weight occasions rpm propeller and due to the different transmissions.SUMMARY OF THE INVENTIONAn object of the present invention to provide a planetary gear transmission for use in gas turbine engines that can be adapted from the standard rotation to reverse rotation by replacing interchangeably support one of the transmission stages .It is a further object of the present invention to provide a motor with a planetary gear transmission that can be converted from a standard rotation to reverse rotation with minimum inventory and wherein the conversion standard for rotation reverse rotation can be performed in the field.It is a further object of the present invention to provide a planetary gear transmission having the two-stage reduction, where the planet stages or may be changed by a similar planetary gear stage that provides a reverse rotation without changing the relationship of transmission gear or the weight thereof.In one construction according to the present invention provides a planetary gear transmission for use in gas turbine engines, including a housing gearbox connected to the motor housing and a ring gear fixed to the inside of the housing into a cavity defined thereby. A first stage planetary gear set is provided in the housing, including a first sun gear coupled to an engine output shaft and a first planet carrier rotatably mounted in the housing. First planetary pinion gears are supported by the first carrier and mesh with the first sun gear and the ring gear. A second stage planetary gear set is provided within the housing and comprises a second sun gear coupled to the first planet carrier. The second stage planetary gear set includes a second planetary carrier coupled to a propeller shaft. The second carrier supports planetary pinion gears meshing with the ring gear and the second sun gear. The first or second planetary carrier is exchangeable for a similar vehicle with a pinion planetary gear arrangement effective for providing the reverse rotation of the propeller shaft.More specifically, the first and second planetary carriers are arranged to rotate the propeller shaft in the standard or the same direction as the motor shaft, and a first or second carrier is provided with additional similar planetary gears meshing with the sun gear pinion gear and ring gear to provide rotation to the respective planetary carrier. Similar to the carrier, the planetary pinion gears are smaller and engaged with the sun gear, while the supplementary pinion planetary gears mesh with the ones with the ring gear.Similarly planet carrier with planetary pinion gears and the pinion gears is complementary radial dimension and the same mass as the planet carrier being replaced, so that the total mass of the planetary gear transmission adapted to reverse rotation is the same as the mass of the transmission planetary gear arranged rotation standard. Moreover, in the planetary carrier similar, the planetary pinion gears and supplementary gears are selected so that the effective transmission ratio of the planetary gear transmission resulting for the reverse rotation is the same as the gear arrangement standard rotating planetary transmission.The advantages of the above provision are substantial. Therefore, a gas turbine engine for driving a propeller may become standard in the field of reverse rotation and vice versa. All that is required is the provision of planetary carriers that correspond to either the first or second stage and adapted to provide reverse rotation as described above. The housing can be divided into the ring gear so that the removal of part of the housing, the first and second planetary stages are exposed, allowing the exchange of the respective planetary carriers. This allows aircraft operators to maintain a small inventory of spare engines and / or complete transmissions. Moreover, since a pair of motors with transmissions described herein, but on the contrary, be balanced in terms of mass and in terms of the propeller rpm resulting simplifies the implementation of a plane torque.Another enhancement is included in this document is the provision of the provisions of auxiliary gear should become planetary gear transmission is reversed. Auxiliary units and accessories are generally perpendicular to the axis of the main propeller and each includes an attachment shaft mounted in suitable bearings and driven bevel gears, one of which is mounted on the attachment shaft and the other of which is mounted on the propeller shaft. In the case of reversing the rotation of the propeller shaft, the bevel gear disposed on the drive shaft 180 rotates must be reversed in its normal direction.Has been the practice to mount such bevel gears in the drive shaft in a manner that does not allow axial expansion or contraction of the drive shaft, although the deflection of the same are compensated. In the present invention, the bevel gear is mounted on the propeller shaft via a spline connection and the shell is supported by suitable bearings.BRIEF DESCRIPTION OF THE DRAWINGSHaving thus generally described the nature of the invention, reference is now made to the accompanying drawings, showing by way of illustration a preferred embodiment thereof, and in which:. Figure 1 is an axial view taken through the planetary gear transmission of the second stage for converting the reverse rotation;. Figure 2 is a schematic view of the planetary gears of the first stage slightly taken along line 2 - 2 of FIG. 1;. Figure 3 is a schematic view of the planetary gears of the second stage of a bit taken along line 4-4 in Fig. 1 but showing the planetary gears rotatably arranged standard;. Figure 4 is a somewhat schematic view along line 4-4 in Fig. 1, showing the gears in the arrangement of FIG. 1 for reverse rotation;. Figure 5 is a fragmentary axial cross section of a further detail of the present invention;. Figure 6 is a fragmentary view similar to FIG. 5 showing the state of the art;. 7 is a partial axial cross section of a detail of another embodiment of the present invention, and. Figure 8 is a fragmentary schematic view of the planetary gear along line 2 - 2 of FIG. 1 showing the first stage in a reverse rotation.Description of the Preferred Embodiments

Referring now to the drawings and especially to FIG. 1, there is shown the gear box of a gas turbine engine adapted to drive a propeller. The planetary gear assembly 10 which forms the gear box includes a housing assembly 12 formed by brackets 14 and 16 are joined along the flanges 18 and 20 by bolts 22. A ring gear 24 extends around the cavity formed by the housing assembly 12 and includes a flange 26 which is securely held between the flanges 18 and 20 of the shells 14 and 16 by bolts 22. The ring gear 24 has a first stage portion 28 with helical grooves and a second portion of the stage 30 with the gear teeth. An output shaft 32 of the gas turbine engine 1 is shown schematically at one end thereof and a propeller shaft 34 is illustrated at the other end of the housing.A planetary gear 36 is coupled to the output shaft 32. The sun gear includes a cylindrical extension 38, as shown in Fig. 1. A first phase of the integrated carrier 40 is provided in the first stage, and includes a cylindrical extension 42 mounted in housing 16 by bearings 43. The first stage carrier 40 includes a pair of hubs 44 and 48. Within the hub 44 is provided an oil passage 46 to lead lubricating oil to the gears, as will be described.In the first stage, as shown in Fig. 2, three gears 64 mounted on a support 40.The gear 64 is mounted in the following manner: A sprocket bolt 50 extends between the hubs 44 and 48 and presses as cylindrical magazine 60. A bolt 70 secures the magazine 60 to the hubs 44 and 48 and also coupled to the covers 52 and 54, respectively. Is the bolt head 58 and nut 56 press against the end caps 54 and 52 which in turn is compressed axially in the bolt 60. This magazine 60 is slightly longer than the width of the centers 44 and 48. Therefore, the hubs 44 and 48 are not pre-loaded. Each gear 64 is mounted in a journal bearing 60 and bearing metal 62 is provided to allow the gear 64 to rotate with minimal friction in the journal 60. Lubricating passageway 46 enter the space formed by the cylindrical magazine 60 and caps 52 and 54 and passes through the filters 68 through conduits 66 in the journal 60 in the bearing metal.Each of the three gears 64 having gear teeth 72 which mesh with the sun gear 36 and ring gear 74. The ring gear 74 is part of the ring gear 28 helically grooved to allow the ring gear 74 to have axial movement, so that as the load increases or decreases, which in turn reacts in the diaphragm Hydraulic 65.A splined coupling 76 is provided in the center of the first stage and extends into the second stage area. The engagement groove 76 includes a splined coupling segment 78 of the extension 48 of the support hub 40.A sun gear 82 is provided in the second stage with internal rifling 83 engaged by the gear segment 80 of the coupling 76.The second stage is shown in Fig. 1 provides for reverse rotation. Therefore, the gears 94 are provided with gears 96 and 94 engage the ring gear portion 30, on one hand, and meshing with gears 96, on the other side. The planetary gears 96 engage the sun gear 82.86 shows the support in the second stage assembly so that the combination of the reverse rotation gear. The gears are mounted on the holder 86 in a manner identical to the assembly described with respect to the gears 64 and carrier 40. The support 86 includes hubs 88 and 90 on 92.Gear 96, shown in Fig. 1 are identified with identical numbers to the numbers used in relation to gear 64, but raised by 100. As shown, the two carriers 86 and 40 are cantilever type carrier, and the carrier 86 has a slotted extension 87 to the propeller shaft 34.. Figure 3 illustrates the second stage of the standard rotation configuration 96a includes five gears mesh 30 and the sprocket 82. Therefore, in the standard rotation, a sun gear 36 rotates the planetary gears 64 against the stationary ring gear 74, causing the carrier 40 to rotate in the same direction as the sun gear.Link jagged 76 transfers This rotation of the sun gear 82. If the second stage is composed of gears 96a, as shown in Fig. 3, below, similarly sun gear 82 rotates the gears 96a against the ring gear 30, causing the bracket 86 to rotate in the same direction as the sun gear 84 and the output shaft 32. If however, reverse rotation is required, the second stage carrier 86 is replaced by a carrier 86 having a combination of gears illustrated by the gears 94 and 96. The gears 94 and 96 are selected to be reasonably equivalent to the weight of the gear 96a from ten gear must be provided with a reverse configuration instead of the five gears in the standard configuration of the rotation of the figure. Three. Moreover, the gears are selected so that the transmission ratio is the same whether it is the standard configuration of rotation of the figure. 3 to the configuration of the reverse rotation of the figure. April. The carriers 86 are identical, except that the machining is different in the region of the gears. Therefore, one physically the same for the reverse rotation, except for the additional machining required because the added amount of gearing.In the case of reverse rotation of the configuration as shown in FIGS. 1 and 4, the sun gear 82 rotates gear 96 which in turn rotates gear 94 in the reverse direction against the sun gear 36 and the resulting rotation is reversed such that the carrier 86 rotates in a reverse direction to the sun gear 82 and the output shaft 32. Since the carrier 86 is connected by spline to the propeller shaft 34, the shaft 34 will rotate in the same direction as the carrier 86 which is opposite to the rotation axis 32.Two-stage transmission is shown in Fig. 1 significantly reduces the rotation thereof for high torque. For example, where the output shaft of the gas turbine may rotate at 30,000 rpm, the propeller shaft 34, given the configuration shown in this application, to rotate at approximately 1600 rpmIn operation, it is noted that although the second stage has been described in terms of normal or reverse rotation, it may be that the first phase is used for providing reverse rotation. In fact, it is even easier to use in the first stage of the first stage in this case has only three gears and therefore the configuration otherwise be fixed gears. . Figure 8 shows the planetary gears arranged to reverse the rotation of the first stage. Therefore, the gears 65 and 67 replace gear 64 in this case.In any case, when changing the rotation of a motor, in particular, the pins 22 are removed to thereby separate the housing 14 of the housing 16. The ring gear 24 can be easily removed from the first stage, due to the splined connection between the ring gear 74 and the ring gear segment 28. The carrier 86 or 40, as the case may be, then, is replaced with a standard configuration or vice versa.As shown in the figure. 5, there is an attachment shaft 228 which is driven by the propeller shaft 34. If given the configuration of the rotation shaft 34, the drive shaft must be amended 228 accessories. Therefore, the bevel gear 222 which is mounted in a bearing 214 via bearings 212 on the housing assembly 210, must be removed and turned 180 which is mounted in bearing 214 in the case of the present invention is driven by a toothed ring 216 mounted on the shaft 34 via the lock nut 218 which threads onto the thread 220. The toothed ring 216 must also be changed in the case of reverse rotation. A toothed ring 216 is provided with slots 224 which engages with the bevel gear 222. The bevel gear 222 has teeth 226 which mesh with teeth 234 on the sprocket 230 fixed to shaft 228 through the cylindrical extension 232 and the articulated bearing sleeve 233.One advantage of this configuration is that the bevel gear 222 is mounted on the housing and the shaft 34 as has been done previously, as shown in Fig. 6 showing the prior art. In this case, the bevel gear 250, as shown, is mounted directly on the shaft 34. Any axial expansion or retraction of the shaft causes the bevel gear 250 to join or loosen against the sprocket 254. In the present invention, the slots 224 allow axial play in relation to the bevel gear 222.. Figure 7 of the drawings shows another embodiment of the gears 94 and 96. Empirically, it has been determined that the ratio of length to diameter of a gear should not exceed 0860. This relationship takes into account the deviation of tooth contact, reliability, durability, etc. To overcome this engagement and to comply with the relation mentioned above, the gears 96 and 94 may be bent, as shown in Figure . 7, for example, the gears 294a and 294b may be, but not necessarily, separated by a spacer 295. Since the gear cylinder is mounted on the magazine 60 in the case of FIG. 1 and 260 in the case of FIG. 7, the rest of the gear assembly does not change although the actual gear cylinder can be duplicado.DescripciónBackground of the Invention1. Field of the InventionThe present invention relates to a planetary gear system, and more particularly to a planetary gear system is used in gas turbine engines.Dos. Description of the Prior ArtIn the field of propulsion propeller aircraft gas turbine and specifically which use two or more motors, is desirable in some aircraft propellers on each side of the fuselage rotating in opposite directions. Since the turbine engine has a standard rotation direction, which is necessary for those applications to provide different gear reduction transmissions to a specific pair of gas turbine engines used on the same aircraft. Often, this means that the turbine engine has a reverse transmission can have a gearbox that is heavier than the standard rotation transmission in the other motor. Moreover, the gear ratios are usually different and thus the rotational speed of each motor is different. Since the transmission of each motor in a pair in a plane is of a different design, the reliability of the transmission may be different, requiring different parts, etc.As can be seen, the standard rotational requirements identical motor reverse rotation transmission is used for feeding a single aircraft propeller requires a substantial inventory since transmissions are intended to be mounted in the manufacturing plant instead of the field.Furthermore, each of the aircraft engine must be regulated independently in the light of the difference in times different propellers rpm due to the different weight transmissions.SUMMARY OF THE INVENTIONAn object of the present invention to provide a planetary gear transmission for use in gas turbine engines that can be adapted from the standard rotation to reverse rotation by replacing interchangeably support one of the transmission stages .It is a further object of the present invention to provide a motor with a planetary gear transmission that can be converted from a standard rotation to reverse rotation with minimum inventory and wherein the conversion standard for rotation reverse rotation can be performed in the field.It is a further object of the present invention to provide a planetary gear transmission having the two-stage reduction, where the planet stages or may be changed by a similar planetary gear stage that provides a reverse rotation without changing the relationship of transmission gear or the weight thereof.In one construction according to the present invention provides a planetary gear transmission for use in gas turbine engines, including a housing gearbox connected to the motor housing and a ring gear fixed to the inside of the housing into a cavity defined thereby. A first stage planetary gear set is provided in the housing, including a first sun gear coupled to an engine output shaft and a first planet carrier rotatably mounted in the housing. First planetary pinion gears are supported by the first carrier and mesh with the first sun gear and the ring gear. A second stage planetary gear set is provided within the housing and comprises a second sun gear coupled to the first planet carrier. The second stage planetary gear set includes a second planetary carrier coupled to a propeller shaft. The second carrier supports planetary pinion gears meshing with the ring gear and the second sun gear. The first or second planetary carrier is exchangeable for a similar vehicle with a pinion planetary gear arrangement effective for providing the reverse rotation of the propeller shaft.More specifically, the first and second planetary carriers are arranged to rotate the propeller shaft in the standard or the same direction as the motor shaft, and a first or second carrier is provided with additional similar planetary gears meshing with the sun gear pinion gear and ring gear to provide rotation to the respective planetary carrier. Similar to the carrier, the planetary pinion gears are smaller and engaged with the sun gear, while the supplementary pinion planetary gears mesh with the ones with the ring gear.Similarly planet carrier with planetary pinion gears and the pinion gears is complementary radial dimension and the same mass as the planet carrier being replaced, so that the total mass of the planetary gear transmission adapted to reverse rotation is the same as the mass of the transmission planetary gear arranged rotation standard. Moreover, in the planetary carrier similar, the planetary pinion gears and supplementary gears are selected so that the effective transmission ratio of the planetary gear transmission resulting for the reverse rotation is the same as the gear arrangement standard rotating planetary transmission.The advantages of the above provision are substantial. Therefore, a gas turbine engine for driving a propeller may become standard in the field of reverse rotation and vice versa. All that is required is the provision of planetary carriers that correspond to either the first or second stage and adapted to provide reverse rotation as described above. The housing can be divided into the ring gear so that the removal of part of the housing, the first and second planetary stages are exposed, allowing the exchange of the respective planetary carriers. This allows aircraft operators to maintain a small inventory of spare engines and / or complete transmissions. Moreover, since a pair of motors with transmissions described herein, but on the contrary, be balanced in terms of mass and in terms of the propeller rpm resulting simplifies the implementation of a plane torque.Another enhancement is included in this document is the provision of the provisions of auxiliary gear should become planetary gear transmission is reversed. Auxiliary units and accessories are generally perpendicular to the axis of the main propeller and each includes an attachment shaft mounted in suitable bearings and driven bevel gears, one of which is mounted on the attachment shaft and the other of which is mounted on the propeller shaft. In the case of reversing the rotation of the propeller shaft, the bevel gear disposed on the drive shaft 180 rotates must be reversed in its normal direction.Has been the practice to mount such bevel gears in the drive shaft in a manner that does not allow axial expansion or contraction of the drive shaft, although the deflection of the same are compensated. In the present invention, the bevel gear is mounted on the propeller shaft via a spline connection and the shell is supported by suitable bearings.BRIEF DESCRIPTION OF THE DRAWINGSHaving thus generally described the nature of the invention, reference is now made to the accompanying drawings, showing by way of illustration a preferred embodiment thereof, and in which:. Figure 1 is an axial view taken through the planetary gear transmission of the second stage for converting the reverse rotation;. Figure 2 is a schematic view of the planetary gears of the first stage slightly taken along line 2 - 2 of FIG. 1;. Figure 3 is a schematic view of the planetary gears of the second stage of a bit taken along line 4-4 in Fig. 1 but showing the planetary gears rotatably arranged standard;. Figure 4 is a somewhat schematic view along line 4-4 in Fig. 1, showing the gears in the arrangement of FIG. 1 for reverse rotation;. Figure 5 is a fragmentary axial cross section of a further detail of the present invention;. Figure 6 is a fragmentary view similar to FIG. 5 showing the state of the art;. 7 is a partial axial cross section of a detail of another embodiment of the present invention, and. Figure 8 is a fragmentary schematic view of the planetary gear along line 2 - 2 of FIG. 1 showing the first stage in a reverse rotation.Description of the Preferred EmbodimentsReferring now to the drawings and especially to FIG. 1, there is shown the gear box of a gas turbine engine adapted to drive a propeller. The planetary gear assembly 10 which forms the gear box includes a housing assembly 12 formed by brackets 14 and 16 are held together along the flanges 18 and 20 by bolts 22. A ring gear 24 extends around the cavity formed by the housing assembly 12 and includes a flange 26 which is securely held between the flanges 18 and 20 of the shells 14 and 16 by bolts 22. The ring gear 24 has a first stage portion 28 with helical grooves and a second portion of the stage 30 with the gear teeth. An output shaft 32 of the gas turbine engine 1 is shown schematically at one end thereof and a propeller shaft 34 is illustrated at the other end of the housing.A planetary gear 36 is coupled to the output shaft 32. The sun gear includes a cylindrical extension 38, as shown in Fig. 1. A first phase of the integrated carrier 40 is provided in the first stage, and includes a cylindrical extension 42 mounted in housing 16 by bearings 43. The first stage carrier 40 includes a pair of hubs 44 and 48. Within the hub 44 is provided an oil passage 46 to lead lubricating oil to the gears, as will be described.In the first stage, as shown in Fig. 2, three gears 64 mounted on a support 40.The gear 64 is mounted in the following manner: A sprocket bolt 50 extends between the hubs 44 and 48 and presses as cylindrical magazine 60. A bolt 70 secures the magazine 60 to the hubs 44 and 48 and also coupled to the covers 52 and 54, respectively. Is the bolt head 58 and nut 56 press against the end caps 54 and 52 which in turn is compressed axially in the bolt 60. This magazine 60 is slightly longer than the width of the centers 44 and 48. Therefore, the hubs 44 and 48 are not pre-loaded. Each gear 64 is mounted in a journal bearing 60 and bearing metal 62 is provided to allow the gear 64 to rotate with minimal friction in the journal 60. Lubricating passageway 46 enter the space formed by the cylindrical magazine 60 and caps 52 and 54 and passes through the filters 68 through conduits 66 in the journal 60 in the bearing metal.Each of the three gears 64 having gear teeth 72 which mesh with the sun gear 36 and ring gear 74. The ring gear 74 is part of the ring gear 28 helically grooved to allow the ring gear 74 to have axial movement, so that as the load increases or decreases, which in turn reacts in the diaphragm Hydraulic 65.A splined coupling 76 is provided in the center of the first stage and extends into the second stage area. The engagement groove 76 includes a splined coupling segment 78 of the extension 48 of the support hub 40.A sun gear 82 is provided in the second stage with internal rifling 83 engaged by the gear segment 80 of the coupling 76.The second stage is shown in Fig. 1 provides for reverse rotation. Therefore, the gears 94 are provided with gears 96 and 94 engage the ring gear portion 30, on one hand, and meshing with gears 96, on the other side. The planetary gears 96 engage the sun gear 82.86 shows the support in the second stage assembly so that the combination of the reverse rotation gear. The gears are mounted on the holder 86 in a manner identical to the assembly described with respect to the gears 64 and carrier 40. The support 86 includes hubs 88 and 90 on 92.Gear 96, shown in Fig. 1 are identified with identical numbers to the numbers used in relation to gear 64, but raised by 100. As shown, the two carriers 86 and 40 are cantilever type carrier, and the carrier 86 has a slotted extension 87 to the propeller shaft 34.. Figure 3 illustrates the second stage of the standard rotation configuration 96a includes five gears mesh 30 and the sprocket 82. Therefore, in the standard rotation, a sun gear 36 rotates the planetary gears 64 against the stationary ring gear 74, causing the carrier 40 to rotate in the same direction as the sun gear.Link jagged 76 transfers This rotation of the sun gear 82. If the second stage is composed of gears 96a, as shown in Fig. 3, below, similarly sun gear 82 rotates the gears 96a against the ring gear 30, causing the bracket 86 to rotate in the same direction as the sun gear 84 and the output shaft 32. If however, reverse rotation is required, the second stage carrier 86 is replaced by a carrier 86 having a combination of gears illustrated by the gears 94 and 96. The gears 94 and 96 are selected to be reasonably equivalent to the weight of the gear 96a from ten gear must be provided with a reverse configuration instead of the five gears in the standard configuration of the rotation of the figure. Three. Moreover, the gears are selected so that the transmission ratio is the same whether it is the standard configuration of rotation of the figure. 3 to the configuration of the reverse rotation of the figure. April. The carriers 86 are identical, except that the machining is different in the region of the gears. Therefore, one physically the same for the reverse rotation, except for the additional machining required because the added amount of gearing.In the case of reverse rotation of the configuration as shown in FIGS. 1 and 4, the sun gear 82 rotates gear 96 which in turn rotates gear 94 in the reverse direction against the sun gear 36 and the resulting rotation is reversed such that the carrier 86 rotates in a reverse direction to the sun gear 82 and the output shaft 32. Since the carrier 86 is connected by spline to the propeller shaft 34, the shaft 34 will rotate in the same direction as the carrier 86 which is opposite to the rotation axis 32.Two-stage transmission is shown in Fig. 1 significantly reduces the rotation thereof for high torque. For example, where the output shaft of the gas turbine may rotate at 30,000 rpm, the propeller shaft 34, given the configuration shown in this application, to rotate at approximately 1600 rpmIn operation, it is noted that although the second stage has been described in terms of normal or reverse rotation, it may be that the first phase is used for providing reverse rotation. In fact, it is even easier to use in the first stage of the first stage in this case has only three gears and therefore the configuration otherwise be fixed gears. . Figure 8 shows the planetary gears arranged to reverse the rotation of the first stage. Therefore, the gears 65 and 67 replace gear 64 in this case.In any case, when changing the rotation of a motor, in particular, the pins 22 are removed to thereby separate the housing 14 of the housing 16. The ring gear 24 can be easily removed from the first stage, due to the splined connection between the ring gear 74 and the ring gear segment 28. The carrier 86 or 40, as the case may be, then, is replaced with a standard configuration or vice versa.As shown in the figure. 5, there is an attachment shaft 228 which is driven by the propeller shaft 34. If given the configuration of the rotation shaft 34, the drive shaft must be amended 228 accessories. Therefore, the bevel gear 222 which is mounted in a bearing 214 via bearings 212 on the housing assembly 210, must be removed and turned 180 which is mounted in bearing 214 in the case of the present invention is driven by a toothed ring 216 mounted on the shaft 34 via the lock nut 218 which threads onto the thread 220. The toothed ring 216 must also be changed in the case of reverse rotation. A toothed ring 216 is provided with slots 224 which engages with the bevel gear 222. The bevel gear 222 has teeth 226 which mesh with teeth 234 on the sprocket 230 fixed to shaft 228 through the cylindrical extension 232 and the articulated bearing sleeve 233.One advantage of this configuration is that the bevel gear 222 is mounted on the housing and the shaft 34 as has been done previously, as shown in Fig. 6 showing the prior art. In this case, the bevel gear 250, as shown, is mounted directly on the shaft 34. Any axial expansion or retraction of the shaft causes the bevel gear 250 to join or loosen against the sprocket 254. In the present invention, the slots 224 allow axial play in relation to the bevel gear 222.. Figure 7 of the drawings shows another embodiment of the gears 94 and 96. Empirically, it has been determined that the ratio of length to diameter of a gear should not exceed 0860. This relationship takes into account the deviation of tooth contact, reliability, durability, etc. To overcome this engagement and to comply with the relation mentioned above, the gears 96 and 94 may be bent, as shown in Figure . 7, for example, the gears 294a and 294b may be, but not necessarily, separated by a spacer 295. Since the gear cylinder is mounted on the magazine 60 in the case of FIG. 1 and 260 in the case of FIG. 7, the rest of the gear assembly does not change even cylinder gear itself can be duplicated.