Planetary mechanism

Thursday 19 September 2013

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 Planetary mechanism

Abstract
A planetary gear having a planetary gear as an input, a fixed ring gear, a planet carrier as an output, the first planetary gear supported by the planetary carrier and meshing with the sun gear and second planetary gears supported by the planet carrier and meshing with the ring gear. A first rotational axis of each first planetary gear is provided closer to a rotation axis of the planet carrier of the planetary gear of a second axis of rotation of each second planetary gear. The torque is transmitted from the first planetary gear of the second planet gears.
Description 
Planetary gear systemThe present invention relates to a planetary gear system .The planetary gear system , such as the transmission mechanism for converting the rotation speed or torque required torque or speed of rotation of the output shaft of the prime mover , and is used the machine tool and transportation means such as a helicopter or vehicle in many cases.Helicopter , the speed of rotation of the gas turbine engine , while a ten thousand revolutions per minute, the speed of rotation of the main rotor is rotated one hundred per minute. In the planetary gear system for helicopters, is while suppressing weight gain , to achieve a large reduction ratio is important.U.S. Patent No. 5472386 discloses a planetary gear system for helicopters. A shaft for supporting a sun gear , a first planetary gear which engages the sun gear , a second planetary gear , a second planetary gear and a first planetary gear , the planetary gear is fixed to engage with the second planetary gear comprises a ring gear .Patent No.U.S. 4856377 , Discloses a planetary gear system for a gas turbine engine . In the planetary gear system , the vehicle comprises a second gear and first gear. Sun gear turns the first gear , the first gear to rotate the second gear . As a result , the carrier rotates in the opposite direction to the sun gear .The purpose of the present invention is to provide a planetary gear system can achieve a greater reduction ratio while suppressing the increase in weight.A sun gear as an input, a gear ring fixed to the planet carrier as an output , is supported on the planet carrier , a first planetary gear that meshes with the sun gear , the planetary gear system according to the present invention , the planet carrier are supported, and includes a second planetary gear meshing with the ring gear . The first axis of rotation of the first planetary gear is arranged at the planetary carrier axis of rotation of the planet carrier near the second axis of rotation of the second planetary gear described above . The torque is transmitted to the second planetary gear of said first planetary gear.The direction of the torque of the planetary carrier about an axis of rotation that acts on the planetary carrier via the first planetary gear of the sun gear , the planetary acting on the planetary carrier via the second planetary gear of said gear ring the torque direction of the rotation axis of carrier to be the same, the torque is transmitted to the second planetary gear is preferred that the first planetary gear . The ring gear is an internal gear .The planetary gear system according to the present invention, which is supported by the planet carrier , further comprising a third sun gear meshing with the second planetary gear and said first preferred planetary gear .Is smaller than the pitch circle diameter of the third planetary gear is preferably the pitch circle diameter of the first planetary gear.Is smaller than the pitch circle diameter of the second planetary gear is preferably the pitch circle diameter of the first planetary gear.The second rotational axis of a third axis of rotation of the third planetary gear , the first rotation axis and above the rotational axis of the sun gear of the sun gear may be disposed in the same plane is preferred . The central axis of the ring gear is arranged coaxially with the axis of rotation of the sun gear .The planetary gear system according to the present invention, which is supported by the planet carrier , further comprising a fourth gear meshing with the planetary ring gear is preferable. The torque is transmitted to the fourth sun gear of the first planetary gear.Preferred is the planetary gear system according to the present invention, a shaft that is rotatably supported on the planet carrier , further comprising a third planetary gear. The third planetary gear and the second planetary gear described above is coupled to the shaft. The torque is transmitted through the third planetary gear to the second planetary gear of said first planetary gear. Pitch diameter of the second planetary gear is smaller than the pitch circle diameter of the third planetary gear.Preferred is the planetary gear system according to the present invention, a shaft that is rotatably supported on the planet carrier , further comprising a third planetary gear. The third planetary gear and said first sun gear is coupled to the shaft . The torque is transmitted through the third planetary gear to the second planetary gear of said first planetary gear. Pitch circle diameter of the third planetary gear is smaller than the pitch circle diameter of the first planetary gear.The planetary gear system according to the present invention , further comprising a shaft which is rotatably supported to the planet carrier , a third planetary gear coupled to the shaft , and a fourth planetary gear is preferably coupled to the shaft . Since the first planetary gear through fourth planetary gears sequentially and above the third planetary gear , the torque is transmitted to the second planetary gear described above . Pitch circle diameter of the fourth planetary gear is smaller than the diameter of the pitch circle of the third gear .The planetary gear system according to the present invention, which is supported by the planet carrier , further comprising a third sun gear meshing with the former being preferred planetary gear . The torque is transmitted through the third planetary gear to the second planetary gear of said first planetary gear. Pitch circle diameter of the first planetary gear is smaller than the pitch circle diameter of the third planetary gear.Preferred is the planetary gear system according to the present invention, a shaft that is rotatably supported on the planet carrier , further comprising a third planetary gear. The third planetary gear and the second planetary gear described above is coupled to the shaft. The torque is transmitted through the third planetary gear to the second planetary gear of said first planetary gear. Pitch diameter of the second planetary gear is smaller than the pitch circle diameter of the third planetary gear.Preferred is the planetary gear system according to the present invention, a shaft that is rotatably supported on the planet carrier , further comprising a third planetary gear. The third planetary gear and the second planetary gear described above is coupled to the shaft. The direction of the torque of the planetary carrier about an axis of rotation that acts on the planetary carrier via the first planetary gear of the sun gear , the planetary acting on the planetary carrier via the second planetary gear of said gear ring the direction of torque of the carrier rotation axis to be the same , the torque is transmitted through the third planetary gear to the second planetary gear of said first planetary gear. The crown is an external gear .The torque is transmitted from the helicopter's engine to the planetary gear is the output torque to the helicopter main rotor of the planet carrier is preferred .According to the present invention there is provided a planetary gear system can achieve a greater reduction ratio while suppressing the increase in weight.

The above object of the present invention , other objects, effects and features will be more apparent from the description of embodiments in conjunction as attached drawings .Figure 1 shows a planetary gear system according to a first embodiment of the present invention. Figure 2A is a top view of a planetary gear system according to a first embodiment. 2B is a side view of a planetary gear system according to a first embodiment. Figure 3A is a top view of a planetary gear system according to the second comparative example . 3B is a side view of a planetary gear system according to the second comparative example . 4A is a top view of a first modification of the planetary gear system according to Embodiment 1. 4B is a side view of a first modification of the planetary gear system according to Embodiment 1. Figure 5A shows a second modification of the planetary gear system according to Embodiment 1. 5B shows a third modification of the planetary gear system according to Embodiment 1 . Figure 6 shows a planetary gear system according to a second embodiment of the present invention. Figure 7 is a top view of a planetary gear system according to a third embodiment of the present invention. Figure 8 is a side view of a planetary gear system according to Embodiment 3 . Figure 9 shows a first modification of the planetary gear system according to Embodiment 3 . Figure 10 shows a second modification of the planetary gear system according to Embodiment 3 . Figure 11 shows a third modification of the planetary gear system according to Embodiment 3 . Figure 12 shows a fourth modification of a planetary gear system according to Embodiment 3 . Figure 13 shows a fifth modification of a planetary gear system according to Embodiment 3 . Figure 14 shows a sixth modification of a planetary gear system according to Embodiment 3 . Figure 15 illustrates a seventh modification of the planetary gear system according to Embodiment 3 . Figure 16 is a top view of a planetary gear system according to a fourth embodiment of the present invention. Figure 17 is a side view of a planetary gear system according to Embodiment 4 . Figure 18A is a top view of a planetary gear system according to a fifth embodiment of the present invention. Figure 18B is a side view of a planetary gear system according to Embodiment 5 . Figure 19 shows a helicopter that has a planetary gear system in accordance with an exemplary embodiment of the present invention.With reference to the accompanying drawings , will be described below planetary gear system according to an exemplary embodiment of the present invention.(Embodiment 1)A ring gear 12 and the sun gear 11 as an input, a fixed one, a planet carrier 13 as an output, the planetary mechanism 10 with reference to Figure 1, according to the first embodiment of the present invention, the support 13 comprising a planetary gear 14 is supported. Y is arranged on the same straight line with the axis of the sprocket 12 and the axis of rotation of the sun gear 11. Is a cylindrical gear such as a worm gear or a spur gear , the ring gear 12 is engaged. The ring gear 12, the pitch circle diameter is larger than the sun gear 11. The gear 14 includes a gear 17 engaging the planetary gears 15 engaging the sun gear 11, a planetary gear 16 engaging the ring gear 12, a planetary gear 16 and planetary gears 15. 17 is disposed in the same plane between the planetary gear 15. Each sun gear 11 , the planetary gears 17 through 15 is a cylindrical gear such as a worm gear or a spur gear , and is an external gear . The planetary gear 16 is arranged inside the ring gear 12. 13th axes of rotation of the planet carrier 13 and the axis of rotation of the sun gear 11 is arranged on the same straight line. Or gear 15 of the planet carrier 13 rotates each planetary 17 (rotation) . 15a rotate the planetary gear shaft 15 , the rotation axis 16a of the planetary gears 16 , 17a axis of rotation of gear 17 , 13a and the axes of rotation of the planet carrier 13 are parallel. Spin axis 15a is arranged in the vicinity of ( the rotation axis of the sun gear 11) rotation axis 13a of rotation axis 16A.When the rotation to the planetary gear 15, sun gear 11 gives a driving force to the sun gear 15 , the planetary gear 15 is allowed to rotate a planetary gear 17 , the planetary gear 17 causes rotation of a planet gear 16 . At this time, the planetary gear 16 carries the sprocket 12 , planetary gear 16 receives a reaction force from the ring gear 12. As a result, rotates in the same direction as the planet carrier 13 and sun gear 11, together with the planet carrier 13 rotates through the sun gear 17 is 15 ( revolution ) .Here , 16 and the planetary gear 15 such that rotation in the same direction , the torque is transmitted through the gear 17 to the planetary gear 16 of the planetary gear 15. Therefore, the direction of the torque acting on the planet carrier 13 through the planetary gear 15 of the planetary gear 11 and the direction of torque acting on the planet carrier 13 through the planetary gear 16, the ring gear 12 is the same . Therefore, the reduction ratio in the planetary gear system 10 is large. Reduction ratio of the planetary gear system 10 is determined by the pitch circle diameter of the crown 12 and the pitch circle diameter of the sun gear 11. Here, the torque applied to the planetary carrier 13 through the planetary gear 16, ring gear 12 is based on the reaction force .Indeed according to the present embodiment will be described with reference to FIG 2A, 2B, 3A, 3B, and 4A and 4B .Figure 2A shows a top view of the planetary mechanism 90 in general. Planetary gear system 90 includes a planetary gear 93 meshing with the sun gear 91, ring gear 92 , ring gear 92 and sun gear 91 . As shown in Figure 2B, the tooth width of the common planetary gear 93 and sun gear 91 is indicated by W 1.3A shows a top view of the planetary gear system 94 . Planetary gear system 94 includes a planetary gear 97 meshing with the sun gear 95 , ring gear 96 , ring gear 96 and sun gear 95 . Pitch diameter of the sun gear 91 and the gear 95 is equal , the pitch diameter is larger than the crown 92 crown 96 . For ( pitch diameter of the pitch diameter circle / sun gear 95 of the crown 96) diameter ratio planetary gear system 94 is larger than ( pitch diameter pitch circle diameter / sun gear 91 of the crown 92) relationship diameter of the planetary gear system 90 , the reduction ratio is greater than the planetary gear system 90 is a planetary mechanism 94 .Moreover, it is necessary to match the spacing of the ring gear 96 and sun gear 95 pitch circle diameter of the planetary gear 97, the planetary gear 97 is increased. As a result, provides the number of the planetary gears 97 capable of planetary gear system 94 is less than the number of the planetary gears 93 capable of planetary gear system 90 is provided . Since the tangential force acting on the planetary gear 97 to a total number of the planetary gear 97 is small becomes large, larger than the width W of the tooth 1 , the width W of the tooth 2 common planetary gear 97 and the gear Solar 95 is shown in figure 3B imperative. Large tooth width W 2 , the weight of the planetary gear system 94 also increases.Figure 4A shows a top view of a planetary gear system 10A according to a first modification of the present exemplary embodiment . Planetary gear system 10A includes a planet carrier 13 and sun gear 11, a ring gear 12 , not shown, drive gear 14 which is supported by the planet carrier 13. Pitch diameter of gear 95 and sun gear 11 is equal pitch diameter of the crown 96 and the crown 12 is equal . The gear 14 includes a planetary gear 15 engaging the sun gear 11 and a planetary gear 16 engaging the ring gear 12. The torque is transmitted through the gear 17 to the planetary gear 16 of the planetary gear 15. Since the role that meshes with the ring gear 12 and the paper engages the sun gear 11, which is shared by the planetary gear 16 and 15, the planetary gears 10A, can be provided with a gear unit 14 of a number . Therefore shows suppression of increase in tooth width W 3 of the common 15 and 17 the planetary gears and the sun gear 11 in FIG 4B are possible.Therefore, according to the present embodiment , it is possible to achieve a large reduction ratio while suppressing the increase in weight of the planetary gear system .In the present embodiment, the rotation axis 15a of the planetary gears 17 and 15 and 16 included in the same gear 14 , 17a and 16a is the plane containing the ( axis of rotation of the sun gear 11) 13a the axis of rotation of the planet carrier 13 is preferably provided . Since the gear unit 14 is connected by the shortest distance between the ring gear 12 and the sun gear 11 , it is possible to ease the gear unit 14.In the present embodiment, it is possible to transmit torque to the sun gear 16 of the planetary gear 15 through the planetary gears of the odd number (three or more ) instead of the gear 17 .Figure 5A shows a planetary gear system 10B according to a second modification of the present exemplary embodiment . 10B planetary gear system includes a ring gear 12 and the sun gear 11 as an input, a fixed one, a planet carrier 13 as an output , the drive gear 14B that is supported by the planet carrier 13. A planetary gear 15B engaging the sun gear 11, a planetary gear 16B engaging the ring 12 , gear 14B 17B includes a planetary gear 16B engaging the sun gear and the planetary gear 15B . 15B, 17B through the planetary gears are arranged in the same plane. Planetary gear 16B is disposed within the ring gear 12. Axis of rotation of the planetary gear 15B is arranged near the axis ( rotation axis of the sun gear 11) of rotation of planetary support 13 to the axis of rotation of the planetary gears 16B. As shown in Figure 5A , the entire rotation axis of the planetary gear 15B ~ 17B can not be disposed in a plane containing the axis of rotation of the planet carrier 13. In some cases, due to a limitation in the number of teeth 17B, is a planetary gear arrangement or 15B.Figure 5B shows a planetary gear system 10C according to a third modification of the present exemplary embodiment . Planetary gear system 10C includes a ring gear 12 and the planetary gear 11 as an input to a fixed planet carrier 13 as an output, the gear 14C which is supported by the planet carrier 13. 14C gearbox includes a planetary gear 15C engaging the sun gear 11, a planetary gear 15C 17C plurality participation planetary gear , and a planetary gear provided plurality 16C corresponding to each planetary gear 17C . 17C through 15C planetary gears are arranged in the same plane. I meshes each of the planetary gears 16C plurality of the ring gear 12 and the planetary gears corresponding 17C . Each planetary gear 16C is arranged inside the ring gear 12. Axis of rotation of the planetary gear 15C is arranged in the vicinity of ( the rotation axis of the sun gear 11) axis of rotation of the planet carrier 13 to the axis of rotation of each planetary gear 16C . In the 14C gear , routes of power between the crown 12 and the sun gear 11 is branched . The strength of such a divergence , acts on the teeth of each ring gear 12 , the planetary gears 17C and 16C is small, avoiding damage to the teeth.second EmbodimentA ring gear 22 and sun gear 21 as an entrance, a fixed planet carrier 23 as an output, the planetary mechanism 20 with reference to Figure 6 , according to the second embodiment of the present invention, the support 23 comprising a planetary gear 24 is supported. Y is arranged on the same straight line with the axis of the sprocket 22 and the axis of rotation of the sun gear 21. Is a cylindrical gear such as a worm gear or a spur gear , the ring gear 22 is meshed . The ring gear 22, the pitch circle diameter is larger than the sun gear 21. The gear 24 includes a planetary gear 27 engaging the planetary gear 25 meshes with the sun gear 21 , a planetary gear 26 meshing with the ring gear 22 , a planetary gear 26 and planetary gears 25 . 27 is arranged in the same plane through the planetary gear 25 . The planetary gear 26 is arranged inside the ring gear 22. Each sun gear 21 , the planetary gears 27 through 25 is a cylindrical gear such as a worm gear or a spur gear , and is an external gear . 23rd axes of rotation of the planet carrier 23 and the axis of rotation of the sun gear 21 is arranged on the same straight line. O planetary gear 25 and the planet carrier 23 rotates each of the 27 (rotation) . Rotation axis 25a of the planetary gears 25 , 26a axis of rotation of the planetary gear 26 , the rotation axis 27a of the planetary gears 27 , 23a and the axes of rotation of the planet carrier 23 are parallel. Rotational axis 25a is disposed in the vicinity of ( the rotation axis of the sun gear 21) rotation axis 23a of rotation axis 26th .

When the rotation to the planetary gear 25, sun gear 21 gives a driving force to the planetary gear 25 , the planetary gear 25 is allowed to rotate a planetary gear 27 , the planetary gear 27 causes rotation of a planet gear 26 . At this time, the planetary gear 26 carries the sprocket 22 , planetary gear 26 receives a reaction force from the ring gear 22. As a result, rotates in the same direction as the planet carrier 23 and sun gear 21 , planet carrier 23 with the rotation 27 through the planetary gear 25 is ( revolution ) .Here , 26 and the planetary gear 25 so that rotation in the same direction , the torque is transmitted through the planetary gear 27 to the planetary gear 26 of the planetary gear 25 . Therefore, the direction of the torque acting on the planet carrier 23 through the planetary gear 25 of the planetary gear 21 and the direction of torque acting on the planet carrier 23 through the planetary gear 26, the ring gear 22 is the same. Therefore, the reduction ratio in the planetary gear system 20 is large. Here, the torque applied to the planetary carrier 23 through the planetary gear 26, ring gear 22 is based on the reaction force .Planetary gear system 20 includes a multiple gear 24 . As the number of drive gear 24 is great , it reduces the force acting on the teeth of each sun gear 27, 21, the ring gear 22 , through planetary gears 25 , avoiding damage to teeth.27 and the planetary gear 26 is arranged outside the planetary gear 25 . That is, the planetary gears 27 and 26 is disposed away from the sun gear 21 than the planetary gear 25 . Since the pitch circle diameter of the planetary gear 25 is smaller than the pitch circle diameter of the planetary gear 27 , which increases the number of drive gear 24 is easy. The pitch circle diameter of the planetary gear 25 is smaller than the pitch circle diameter of the planetary gear 26 also makes it easy to increase the number of gear unit 24.The planetary gear 26 is arranged outside the planetary gear 27. That is, the planetary gear 26 is positioned away from the sun gear 21 than the planetary gear 27. The pitch circle diameter of the planetary gear 27 is smaller than the pitch circle diameter of the planetary gear 26 is preferable in terms of increasing the number of gear unit 24.Can increase the number of gear unit 24 which is easy to be apparent from a comparison of Figure 6 and Figure 1.( Embodiment 3 )A ring gear 32 and sun gear 31 as an input, the fixed planetary gear system 30 with reference to Figure 7 , according to the third embodiment of the present invention includes a gear unit 34 . The axis of the sprocket 32 and the axis of rotation of the sun gear 31 to be disposed in the same straight line , the ring gear 32 and sun gear 31 is arranged at different levels. Is a cylindrical gear such as a worm gear or a spur gear , the ring gear 32 is meshed . The ring gear 32, the pitch circle diameter is larger than the sun gear 31. I meshes with planetary gears 38 and the planetary gear 35 involving 31 , a planetary gear 36, the ring gear share 32, and homologs , and the planetary gear 36 rotates ( rotates ) , the gear 34 includes a planetary gear 38 and the planetary gear 35 include a planetary gear 37 . Each sun gear 31, 38 through the planetary gear 35 is a cylindrical gear such as a worm gear or a spur gear , and is an external gear . Planetary gear 36 is disposed within the crown 32 .With reference to Figure 8, the planetary mechanism 30 includes a planetary carrier 33 as an output. Company Planet 33 , to support the gear 34 . Rotating shafts 33a of the planet carrier 33 and the axis of rotation of the sun gear 31 is arranged on the same straight line. O planetary gear 35 to the planet carrier 33 rotates each of the 38 (rotation) . The planetary gear 38 and the planetary gear 36 is coupled to shaft 39 . Planet carrier 33, to support the rotating shaft ( rotatably ) 39. Planet carrier 33 is disposed between the planetary gears 38 and 35, 37 and the planetary gear 36 . And planetary gears 38 and 35 and 37 , the planetary gear 36, and are organized at different levels.Spin axis 35a of the planetary gear 35, the rotation axis 36a of the joint 38 and the planetary gear 36, the rotation axes 37 of the planetary gear 37a , 33a and the axes of rotation of the planet carrier 33 are parallel. Rotational axis 35a is disposed in the vicinity of ( the rotation axis of the sun gear 31) axis of rotation 33a that the rotation axis 36a .When the rotation to the planetary gear 31, sun gear 35 gives a driving force to the planetary gear 35, the planetary gear 35 is allowed to rotate a planetary gear 37, the planetary gear 37 causes rotation of a planet gear 38 . Planetary gear 38 and rotates, the planetary gear 36 also rotates in counterparts and planetary gears 38 . At this time, the planetary gear 36 carries the sprocket 32, planetary gear 36 receives a reaction force from the ring gear 32 . As a result, rotates in the same direction as the planet carrier 33 and sun gear 31 , the planetary gear 38 through the planetary gear 35 rotates ( revolves ) both planet carrier 33 .Here , 36 and the planetary gear 35 such that rotation in the same direction , the planetary gear 36 of the planetary gear 35, the torque is transmitted through the planetary gear 37 , the shaft 39 and the planetary gears 38 . Therefore, the direction of the torque acting on the planet carrier 33 through the planetary gear 35 of the planetary gear 31 and the direction of torque acting on the planet carrier 33 through the planetary gear 36 of the ring gear 32 is the same. Therefore, the reduction ratio in the planetary gear system 30 is large. Here, the torque applied to the planetary carrier 33 through the planetary gear 36 ring gear 32 is based on the reaction force .Pitch diameter D 36 of the planetary gear 36 is smaller than the pitch diameter D 38 of the planetary gear 38 , to contribute to increase the percentage reduction of the planetary gear system 30.Is possible to make different from each other dimensions of the teeth of the planetary gears 38 and 36 .It is possible to arrange any number of any gear position a pair of planetary gears engaging with the shafts.A ring gear 32 and sun gear 31 as an entrance, a fixed planet carrier 33 as an output planetary gear system 30A with reference to Figure 9 , according to a first modification of the present exemplary embodiment , the planet carrier 33 comprising a drive gear 34A is supported. A planetary gear 35A engaging the sun gear 31, a planetary gear 36A engaging the ring gear 32, a planetary gear 38A counterparts with planetary gear 36A rotates ( revolves ) 34A gear meshing with the planetary gears gears 38A and 35A 37A included a planetary planetary gears. Each 38A is an external gear and the cylindrical gear or planetary gear 35A , the planetary carrier 33 rotates (rotation) . Planetary gear 38A and 36A of the planetary gears are coupled to the shaft 39A . The planetary gears 36A, the pitch circle diameter is smaller than the planetary gears 38A . Company Planet 33 , to support the ( rotating ) rotatable shaft 39A . 35A through 38A of the planetary gear is disposed on the same side of the planet carrier 33 . Planetary gears 35A, 37A and 38A , the planetary gear 36A , and arranged staggered. Planetary gear 36A is disposed within the ring gear 32 .A ring gear 32 and sun gear 31 as an entrance, a fixed planet carrier 33 as an output, the planetary gear system 30B with reference to Figure 10 , according to a second modification of this form of exemplary embodiment, the planet carrier 33 I 34B comprises a computer unit that is compatible . A planetary gear 35B meshing with the sun gear 31 , a planetary gear 36B meshing with the ring gear 32 and the planetary gear 37B engaging the planetary gear 35B , homologs with the planetary gear 37B rotates , drive gear (rotation ) 34B , 36B planetary gear and a planetary gear 38B engage with. 38B each is an external gear and the cylindrical gear or planetary gear 35B to the planet carrier 33 rotates (rotation) . The planetary gear 38B and the planetary gear 37B are coupled to the shaft 39B . Pitch circle diameter is smaller than the planetary gear 38B planetary gear 37B . Company Planet 33 , to support the ( rotating ) rotatable shaft 39B . And gear 37B and 35B and 38B and 36B planetary planetary gear , and are organized at different levels. Planetary gear 36B is disposed within the ring gear 32 .A ring gear 32 and sun gear 31 as an entrance, a fixed plaet carrier 33 as an output, the planetary gear system 30C by reference to Figure 11 , according to a third modification of this form of exemplary embodiment, the planet carrier 33 comprising a drive gear 34C which is compatible . A planetary gear 35C coupling the sun gear 31 , planetary gear coupling 36C ring gear 32, a planetary gear 37C to 35C counterparts with planetary gear rotates ( turns ) 36C 34C gear meshes with the planet gears and 37C planetary gear I and a planetary gear 38C . Each of the 38 C is an external gear and the cylindrical gear or planetary gear 35C , the planetary carrier 33 rotates (rotation) . Planetary gear 37 ° C and 35 ° C of planetary gears are coupled to a shaft 39C . Pitch circle diameter is smaller than the planetary gear 37C planetary gear 35C . Company Planet 33 , to support the rotating shaft 39C (rotation ) . A planetary gear 35C and 38C through 36C of ​​the planetary gear and arranged staggered. Planetary gear 36C is disposed within the ring gear 32 .A ring gear 32 and sun gear 31 as an input, a fixed one, a planet carrier 33 as an output, the planetary gear 30D with reference to Figure 12, according to a fourth modification of the present exemplary embodiment , the planet carrier 33 comprising a gear 34D which is compatible . A planetary gear 35D meshes with the gear 31, a planetary gear 36D meshes with the crown gear 32 ' , and the planetary gear 35D - 35D counterparts planetary gear with planetary gear 35D rotates (rotation) 34D gear, the planetary gear engages ' and planetary gear 37D - planetary gear 37D and 37D counterparts , a planetary gear 37D rotates (rotation) to engage , and a planetary gear 36D ' that homologues with the planetary gear 36D rotates (rotation) . Each planetary gear 35D ~ 37D , the 35D - 37D ~ ' is an external gear and the spur gear to the planet carrier 33 rotates ( turns ) . Planetary gear 35D ' and 35D planetary gear is coupled to a shaft 39D . Planetary gear planetary gear 37D and 37D ' 39D axis ' are coupled . ' It . 35D planetary gear is coupled to a shaft 39D " ' planetary gear 36D and 36D pitch diameter planet gear is smaller than the planetary gear 35D , the pitch circle diameter is smaller than the planetary gear 37D planetary gear 37D ' . planetary support 33 pitch diameter is larger than the 36D supports planetary gear (rotating ) rotatable shaft 39D ~ 39D " planetary gear 36D . As shown in Figure 12, the planetary gear 35D ~ 37D , 35D ' ~ 37D ' are arranged staggered. Planetary gear 36D , and is disposed within the ring gear 32 .Planetary gear system 30A ' with reference to Figure 13, according to a fifth modification of the present embodiment corresponds to a combination of the configuration of a planetary gear system 10C to the configuration of the planetary gear system 30A. 30A planetary gear system ' includes a ring gear 32 and sun gear 31 as input to the fixed planet carrier 33 as a 34A gearbox output which is supported by the planet carrier 33' includes a. Gear 34A 'a planetary gear 35A engaging the sun gear 31 , planetary gears 37A plurality of planetary gears meshing 35A, a planetary gear 38A of the plurality of provided corresponding to each planetary gear 37A , the planetary gears 38a provided so as to correspond to , and a planetary gear 36A engaging the ring gear 32 . A planetary gear 36A which meshes with planet gears 37A corresponding homologs corresponding to the rotation of the planetary gears 38A and ( turns). Each 38A is an external gear and the cylindrical gear or planetary gear 35A , the planetary carrier 33 rotates (rotation) . Planetary gear 38A and the planetary gear 36A are coupled to the shaft. Planet carrier 33, to support the rotating shaft ( rotationally ) . The planetary gears 36A, the pitch circle diameter is smaller than the planetary gears 38A . Planetary gears 35A, 37A and 38A , the planetary gear 36A , and arranged staggered. Each planetary gear 36A is arranged inside the ring gear 32 .Planetary gear system 30B ' with reference to Figure 14, according to a sixth modification of the present embodiment corresponds to a combination of the configuration of a planetary gear system 10C to the configuration of the planetary gear system 30B. Planetary gear system 30B 'includes a ring gear 32 and sun gear 31 as an input to a fixed planet carrier 33 as an output gear 34B that is supported by the planet carrier 33' includes a. The gear 34B ", a planetary gear 35B engaging the sun gear 31 , a planetary gear 35B 37B plurality participation planetary gear , a planetary gear 38B is provided for each planetary gear 37 , corresponding to each planet gear 38B and plurality of planetary gears 36B which are provided with . A planetary gear 37 that corresponds to rotation of the planetary gear counterparts 38B is ( rotation). 36B Each planetary gear meshes with the ring gear 32 and planetary gears for 38B . 38B each is an external gear and the cylindrical gear or planetary gear 35B to the planet carrier 33 rotates (rotation) . The planetary gear 38B and the planetary gear 37B are coupled to the shaft. Planet carrier 33, to support the rotating shaft ( rotationally ) . Pitch circle diameter is smaller than the planetary gear 38B planetary gear 37B . And gear 37B and 35B and 38B and 36B planetary planetary gear , and are organized at different levels. Each planetary gear 36B is arranged inside the ring gear 32 .Planetary gear system 30C ' with reference to Figure 15 , according to a seventh modification of the present embodiment corresponds to a combination of the configuration of a planetary gear system 10C to the configuration of the planetary gear system 30C . Planetary gear system 30C ' includes the ring 32 and sun gear 31 as an input to a fixed planet carrier 33 as an output gear 34C which is supported by the planet carrier 33' includes a. The gear unit 34C ' , a planetarium gear 35C engaging the sun gear 31 , a planetary gear 37C that homologous with the planetary gear 35C rotates ( turns ), a plurality of planetary gears 38C which are provided to correspond to the planetary gear 37 ° C, and each provided a plurality of planetary gears 36C which correspond to the planetary gear 38C . Each of the 38 C is an external gear and the cylindrical gear or planetary gear 35C , the planetary carrier 33 rotates (rotation) . Planetary gear 37 ° C and 35 ° C planetary gear are coupled to the shaft. Planet carrier 33, to support the rotating shaft ( rotationally ) . Pitch circle diameter is smaller than the planetary gear 37C planetary gear 35C . Each planet gear meshes with 38C 37C corresponding planetary gear . 36C Each planetary gear meshes with the ring gear 32 and 38 º C corresponding planetary gear . Each of the 38 C is an external gear and the cylindrical gear or planetary gear 35C , the planetary carrier 33 rotates (rotation) . A planetary gear 35C and 38C through 36C of ​​the planetary gear and arranged staggered. Each planetary gear 36C is arranged inside the ring gear 32 .In 30D through '30C ' 30A , making different from each other tooth thickness of the two planetary gear which engages with a common axis are possible via the planetary gear system 30A.( Embodiment 4 )A ring gear 42 and sun gear 41 as an input, a fixed one, a planet carrier 43 as an output, the planetary mechanism 40 with reference to Figure 16 , according to the fourth embodiment of the present invention, the support 43 which comprises a planetary gear 44 is supported. Y is arranged on the same straight line with the axis of the sprocket 42 and the axis of rotation of the sun gear 41 . Is a cylindrical gear such as a worm gear or a spur gear , the ring gear 42 is meshed . The ring gear 42, the pitch circle diameter is larger than the sun gear 41 . The gear 44 includes a chain 65 which engages a planetary gear 45 meshing with the sun gear 41, a planetary gear 46 meshing with the sprocket 42, a sprocket 61, a sprocket 62, the sprocket 62 and the wheel gear 61 . Each sun gear 41, planetary gears 46 and 45 is a cylindrical gear such as a worm gear or a spur gear , and is an external gear . Planetary gear 46 is disposed within the crown 42 . Rotating shafts 43a of the planet carrier 43 and the axis of rotation of the sun gear 41 is arranged on the same straight line.Referring to Figure 17, the gear 61 and the planetary gear 45 is coupled to the shaft 51, the gear 62 and the planetary gear 46 is coupled to shaft 52 . Planet carrier 43 rotatably supporting the shaft 52 and 51. By 43 rotation planetary gear carrier counterparts planetary gear 61 and 45, ( turns). By 43 rotation planetary gear carrier counterparts 62 and the planetary gear 46 ( rotation).Rotating shaft 45a of the common gear 61 and the planetary gear 45, the axis 46a of rotation of the common gear 62 and the planetary gear 46, 43a and the axes of rotation of the planet carrier 43 are parallel. Spin axis 45a is arranged near the rotation axis 43a ( the axis of rotation of the sun gear 41) than the spin axis 46a .When thereby rotating the planetary gear 45 sun gear 41 gives a driving force to the planetary gear 45, the sprocket 61 rotates with the planetary gear counterparts 45 thereby rotating the sprocket 62 via a chain 65, the planetary gear 46 is also a sprocket 62 rotates counterparts me . At this time, the planetary gear 46 has the ring gear 42, planetary gear 46 receives a reaction force from the ring gear 42 . As a result, rotates in the same direction as the planet carrier 43 and sun gear 41, the planetary gear 45, the planetary gear 46, the sprocket 62 and the sprocket 61 is rotated ( revolved ) together planet carrier 43 .
Here , 46 and the planetary gear 45 such that rotation in the same direction, the planetary gear 46 of the planetary gear 45, the torque is transmitted through the shaft 51, the sprocket 61 , the chain 65 , the sprocket 62, a shaft 52 . Therefore, the direction of the torque acting on the planet carrier 43 through the planetary gear 45 of the planetary gear 41 and the direction of torque acting on the planet carrier 43 through the planetary gear 46 of the ring gear 42 is the same. Therefore, the reduction ratio in the planetary gear system 40 is large. Here, the torque applied to the planetary carrier 43 through the planetary gear 46 ring gear 42 is based on the reaction force .Planetary gear system 40 includes a multiple gear 44 . As the number of drive gear 44 is great , it reduces the force acting on the teeth of each sun gear 41, ring gear 42 , planetary gears 46 and 45, 62 and sprocket 61 .You can do differently from each other dimensions of the teeth of the planet gears 46 and 45 .( Embodiment 5 )Like previous embodiments , it is preferred in terms of placement inside the ring gear of the planetary gear engaging the ring gear to increase the reduction ratio , but to some extent the reduction ratio of the arrangement can be reversed crown gear and the sun gear is premium may increase .A ring gear 72 and sun gear 71 as an input, a fixed one, a planet carrier 73 as an output, the planetary mechanism 70 with reference to Figure 18A , according to a fifth embodiment of the present invention, the support 73 which comprises a planetary gear 74 is supported. To be on the same straight line with the axis of the sprocket 72 and the axis of rotation of the sun gear 71, ring gear 72 and sun gear 71 is provided at different levels. A cylindrical gear such as a worm gear or spur gear , ring gear 72 is an external gear . The ring gear 72, the pitch circle diameter is larger than the sun gear 71 . A planetary gear 75 meshing with the sun gear 71, a planetary gear 76 meshes with the crown gear 72, meshes with the sun gear 75, gear unit 74 includes a planetary gear 77 with the planetary gear counterparts 76 rotates ( turns). Planetary gear 76 is disposed outside of the crown 72 . Each sun gear 71, 77 through the planetary gear 75 is a cylindrical gear such as a worm gear or a spur gear , and is an external gear . Axis of rotation of the planet carrier 73 and the axis of rotation of the sun gear 71 is arranged on the same straight line. To the planet carrier 73 rotates the sun gear 75 ( turns). Planetary carrier 73 for rotation of the planetary gear counterparts 77 and the planetary gear 76 (rotation) . Spin axis of the planetary gear 75, the rotation axis of the joint 77 and the planetary gear 76 and the rotation axis of the planetary carrier 73 are parallel. Axis of rotation of the planetary gear 75 is arranged in the vicinity of ( the rotation axis of the sun gear 71) axis of rotation of the planet carrier 73 to the axis of rotation of the common planetary gear 77 and planetary gears 76 .With reference to Figure 18B , the planetary gear 77 and the planetary gear 76 is coupled to shaft 79 . Pitch circle diameter is smaller than the planetary gear 77 to the planetary gear 76 . Company Planet 73, supports the (rotation ) can rotate the shaft 79 . 77 and the planetary gear 75, the planetary gear 76, and disposed at different levels.When the rotation to the planetary gear 75 sun gear 71 gives a driving force to the planetary gear 75, the planetary gear 75 causes rotation of a planet gear 77 . Planetary gear 77 and rotates , the planetary gear 76 also rotates counterparts and planetary gears 77 . At this time, the planetary gear 76 that carries the ring gear 72, planetary gear 76 receives a reaction force from the ring gear 72 . As a result, rotates in the same direction as the planet carrier 73 and sun gear 71, the planetary gear 77 through the planetary gear 75 rotates ( revolves ) in both the planet carrier 73 .Here , 76 and the planetary gear 75 for rotation in opposite directions, the planetary gear 76 of the planetary gear 75 , torque is transferred through the shaft 79 and the planetary gears 77 . Since ring gear 72 is an external gear and the direction of torque acting on the planet carrier 73 through the planetary gear 75 of the planetary gear 71, the direction of the torque acting on the planet carrier 73 through the sun gear 76 of the ring gear 72 is the same door . Therefore, the reduction ratio in the planetary gear system 70 is large. Here, the torque applied to the planetary carrier 73 through the planetary gear 76 ring gear 72 is based on the reaction force .

Is possible to make different from each other dimensions of the teeth of the planetary gears 77 and 76.Figure 19 shows a helicopter that includes a planetary gear system 10 . A motor 2 , a rotary cutter ( main rotor ) 3, helicopter, comprises a 4 transmission for transmitting power ( torque ) to rotate the sheet 3 of engine 2 . Transmission 4 comprises a planetary gear system 10 . Planetary gear system 10 is housed in the transmission casing 4 (not shown). Four transmission housing , rotatably supporting the planet carrier 13 and the gear 11. The ring gear 12 is fixed to the transmission casing 4 . Sun gear 11 is mechanically connected to output shaft of the motor 2. Planet carrier 13 is mechanically connected to rotor 3. Power ( torque ) is transmitted from the engine 2 to the sun gear 12, the power ( torque ) is output to the drive 3 from the planet carrier 13.Instead of planetary gear system 10, the chopper may be provided in one of the planetary gear system as described above .
Issues described above can be combined . Also be used as a planetary gear bevel gears , to tilt the axis of rotation of planetary support with respect to ( revolution axis ) the axis of rotation of the planetary gear .As an effect of the common planetary gear system according to the exemplary embodiment , the following points may be mentioned. Since the role that meshes with the ring gear meshing with the role the sun gear , which is shared by the planetary gear planetary mechanism different, can be provided with a gear unit of a number. Therefore, it is possible to achieve high reduction ratio while suppressing the increase in weight of the planetary gear system .

Accordingly, a suitable transport means requires lighter planetary gear system according to the embodiment is particularly suitable for helicopters.Having described the invention with reference to embodiments, the present invention is not intended to be limited to the above embodiment . It is possible to make various modifications to the embodiments described above .This application claims priority based on Japanese Patent Application No. 2008-37620 filed on February 19, 2008, which application is incorporated herein in its entirety for disclosure.