Patent Publication Number: US-2021172509-A1

Title: Transmission series

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National Phase Application under 35 U.S.C. § 371 of International Application No. PCT/EP2019/063273, filed on May 23, 2019, and claims benefit to German Patent Application No. DE 10 2018 210 131.0, filed on Jun. 21, 2018. The International Application was published in German on Dec. 26, 2019 as WO 2019/242976 under PCT Article 21(2). 
    
    
     FIELD 
     The invention relates to a series of transmissions that each have a first planetary stage and a second planetary stage. 
     BACKGROUND 
     The construction and manufacture of transmissions requires a considerable effort in terms of investment and resources. Many providers therefore strive to cover as many applications as possible with a single transmission type. However, this leads to the transmission being overdimensioned in applications with low loads. An overdimensioned transmission in turn offers potential for cost savings. 
     In view of this background information, the development of a transmission series seems appropriate. On the one hand, a production series makes it possible to use components in different transmissions of the series. On the other hand, the transmissions of the series can be adapted to specific applications. Both factors have a cost-saving effect. 
     In the field of wind turbines, however, conventional types of transmission series could not be established so far. The use of series is difficult here, since the plant manufacturers specify highly deviating interfaces between the system and the transmission. Furthermore, a strongly varying band width of load cases has to be covered. 
     The publication DE 100 28 046 A1 discloses a series of revolving transmissions whose transmissions differ by varying tooth widths. The transmissions may be executed as multi-stage. However, the variation in the tooth widths affects only a single transmission stage. 
     SUMMARY 
     In an embodiment, the present invention provides a series of transmissions. The series includes a first transmission and a second transmission. The transmissions each have a first planetary stage and a second planetary stage. The first planetary stage and the second planetary stage each have a ring gear, a planetary carrier with one or more planetary gears and a sun gear. A width of the planetary gears of the first planetary stage of the first transmission is smaller than a width of the planetary gears of the first planetary stage of the second transmission. A width of the planetary gears of the second planetary stage of the first transmission is smaller than a width of the planetary gears of the second planetary stage of the second transmission. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be described in even greater detail below based on the exemplary figures. The invention is not limited to the exemplary embodiments. All features described and/or illustrated herein can be used alone or combined in different combinations in embodiments of the invention. The features and advantages of various embodiments of the present invention will become apparent by reading the following detailed description with reference to the attached drawings which illustrate the following: 
         FIG. 1  shows a first transmission diagram; 
         FIG. 2  shows a second transmission diagram; and 
         FIG. 3  shows a transmission series. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure provides transmissions for wind turbines that avoid inherent disadvantages of solutions known from the prior art. In particular, costs should be reduced without impairing technical properties. 
     A series is defined as a plurality of individual devices. The series according to the present disclosure consists of transmissions, preferably transmissions for wind turbines, and comprises at least one first transmission and one second transmission. 
     Each transmission of the series has a first planetary stage and a second planetary stage. The second planetary stage is connected downstream from the first planetary stage. This means that the first planetary stage is arranged in a torque flow from an input to an output of the transmission upstream of the second planetary stage. A torque is transmitted from the first planetary stage to the second planetary stage. 
     A planetary stage is a transmission stage with a ring gear, a sun gear, a planetary carrier and one or more, preferably structurally identical, planetary gears. The planetary gears are rotatably supported in the planetary carrier and respectively mesh with the ring gear and/or the sun gear. Two of the three components sun gear, planetary carrier and ring gear are rotatably mounted. The third component is arranged to be rotationally fixed. 
     The width of the planetary gears of the first planetary stage of the first transmission is smaller than the width of the planetary gears of the first planetary stage of the second transmission. 
     The width of a gear is a designation for the width of its teeth. This in turn refers to the spatial extent of the teeth in the axial direction, that is to say along an axis of rotation of the gear. This is based on the assumption that all teeth of the gear are of equal width. 
     According to the present disclosure, the width of the planetary gears of the second planetary stage of the first transmission is also smaller than the width of the planetary gears of the second planetary stage of the second transmission. As a result, the transmissions of the series can be adapted particularly well to the occurring load cases. In particular, an excessively powerful design of individual planetary stages, which is accompanied by unnecessarily high costs, can be avoided. 
     In a preferred refinement, the number of planetary gears of the first planetary stage of the first transmission corresponds to the number of planetary gears of the first planetary stage of the second transmission. This makes it possible to use identical planetary carriers in the first planetary stage of the first transmission and in the first planetary stage of the second transmission. 
     In general, two components are structurally identical if they are the same apart from manufacturing tolerances. In particular, all physical parameters of the components, such as the dimensions or the material properties, coincide within the scope of manufacturing tolerances. Components of the same type are characterized in that they are interchangeable with one another. 
     In a preferred refinement, the number of planetary gears of the second planetary stage of the first transmission also corresponds to the number of planetary gears of the second planetary stage of the second transmission. Identical planetary carriers can thereby be realized in the second planetary stage of the first transmission and in the second planetary stage of the second transmission. 
     In a further preferred refinement, the number of planetary gears of the first planetary stage of the first transmission corresponds to the number of planetary gears of the second planetary stage of the first transmission. The same applies preferably to the number of planetary gears of the first planetary stage of the second transmission and the number of planetary gears of the second planetary stage of the second transmission. 
     In addition to the first transmission and the second transmission, the series is preferably further developed with a third transmission and a fourth transmission. The third transmission and the fourth transmission also each have a first planetary stage and a second planetary stage. The width of the planetary gears of the first planetary stage of the third transmission is smaller than the width of the planetary gears of the first planetary stage of the fourth transmission. Similarly, the width of the planetary gears of the second planetary stage of the third transmission is smaller than the width of the planetary gears of the second planetary stage of the fourth transmission. 
     In a preferred refinement, the width of the planetary gears of the first planetary stage of the third transmission corresponds to the width of the planetary gears of the first planetary stage of the first transmission. Thus, for example, the sun gears and the ring gears of the first planetary stages of the first transmission and of the third transmission can be configured identically. In particular, it is possible to use identical planetary gears in the first planetary stages of the first transmission and of the third transmission. 
     In a preferred refinement, the width of the planetary gears of the second planetary stage of the third transmission corresponds to the width of the planetary gears of the second planetary stage of the first transmission. This allows the use of identical ring gears, sun gears and in particular planetary gears in the second planetary stages of the first transmission and of the third transmission. 
     In a preferred refinement, the width of the planetary gears of the first planetary stage of the fourth transmission corresponds to the width of the planetary gears of the first planetary stage of the second transmission. In this way, identical ring gears, sun gears and in particular planetary gears can be used in the first planetary stages of the second transmission and of the fourth transmission. 
     Finally, in a preferred refinement, the width of the planetary gears of the second planetary stage of the fourth transmission corresponds to the width of the planetary gears of the second planetary stage of the second transmission, so that once again identical ring gears, sun gears and especially planetary gears can be used. 
     In a further preferred refinement, the number of planetary gears of the first planetary stage of the third transmission corresponds to the number of planetary gears of the first planetary stage of the fourth transmission. Consequently, identical planetary carriers can be used for the first planetary stages of the third transmission and of the fourth transmission. 
     In a preferred refinement, the number of planetary gears of the second planetary stage of the third transmission and the number of planetary gears of the second planet stage of the fourth transmission also coincide, so that identical planetary gears can be used in the second planetary stages of the third transmission and of the fourth transmission. 
     In a preferred refinement, the number of planetary gears of the first planetary stage of the third transmission corresponds to the number of planetary gears of the second planetary stage of the third transmission. The same applies preferably to the number of planetary gears of the first stage of the fourth transmission and the number of planetary gears of the second planetary stage of the fourth transmission. 
     In contrast, the number of planetary gears of the first planetary stage of the third transmission in a preferred refinement is greater than the number of planetary gears of the first planetary stage of the first transmission. Similarly, in preferred refinements, the number of planetary gears of the second planetary stage of the third transmission is greater than the number of planetary gears of the second planetary stage of the first transmission, the number of planetary gears of the first planetary stage of the fourth transmission is greater than the number of planetary gears of the first planetary stage of the third transmission and/or the number of planetary gears of the second planetary stage of the fourth transmission is greater than the number of planetary gears of the second planetary stage of the second transmission. 
     In a preferred refinement, the transmissions of the series have, in addition to the first planetary stage and the second planetary stage, a third transmission stage, which is preferably designed as a planetary stage. This is preferably connected downstream of the second planetary stage; i.e., is found in a torque flow which runs from the input to the output of the transmission downstream of the second planetary stage. In particular, the second planetary stage can be arranged axially between the first planetary stage and the third transmission stage. 
     In preferred refinements, the third transmission stages of the first transmission and of the second transmission and/or the third transmission stages of the third transmission and of the fourth transmission are identical in their design. 
     Preferred exemplary embodiments of the invention are shown in the figures. Here, matching reference numbers indicate identical or functionally identical features. 
     The diagrams in  FIGS. 1 and 2  represent the transmission  101  with a first planetary stage  103 , a second planetary stage  105 , and a third planetary stage  107 . The transmission  101  further has an input shaft  109  and an output shaft  111 . 
     The input shaft  109  is non-rotatably connected to a rotatable planetary carrier  113  of the first planetary stage  103 . The first planetary stage  103  also has a ring gear  115 , planetary gears  117  and a sun gear  119 . The planetary gears  117  are rotatably supported in the planetary carrier  113  and mesh with the ring gear  115  and the sun gear  119 . The ring gear  115  is arranged in a rotationally fixed manner and the sun gear  119  is rotatable. 
     Via a first intermediate shaft  121 , the sun gear  119  of the first planetary stage  103  is connected non-rotatably to a rotatable planetary carrier  123  of the second planetary stage  105 . The design of the second planetary stage  105  corresponds to the design of the first planetary stage  103 . Correspondingly, the second planetary stage  105  has a rotationally fixed ring gear  125 , planetary gears  127  that are rotatably supported in the planetary carrier  123 , and a rotatable sun gear  129 . The planet gears  127  are rotatably supported within the planetary carrier  123  and mesh with the ring gear  125  and the sun gear  129 . 
     In accordance with  FIG. 1 , the sun gear  129  of the second planetary stage  105  is connected to a planetary carrier  133  of the third planetary stage  107  in a non-rotatable manner via an intermediate shaft  131 . The design of the third planetary stage  107  according to  FIG. 1  corresponds to the design of the first planetary stage  103  and the second planetary stage  105 . Accordingly, the third planetary stage  107  has a rotationally fixed ring gear  135 , planetary gears  137  and a rotatable sun gear  139 . The planetary gears  137  are rotatably supported in the planetary carrier  133  and mesh with the ring gear  135  and the sun gear  139 . The sun gear  139  is non-rotatably connected with the output shaft  111 . 
     The transmission  101  shown in  FIG. 2  differs from the transmission shown in  FIG. 1  by the design of the third planetary stage  107 . Here, the ring gear  135  is rotatably supported and connected to the sun gear  129  of the second planetary stage  105  in a non-rotatable manner via the second intermediate shaft  131 . The planetary carrier  133  is arranged in a non-rotatable manner. 
       FIG. 3  outlines a transmission series. The transmissions contained in the series can be constructed approximately as shown in  FIG. 1 or 2 . 
     The series comprises six transmissions with three different mountings  301 ,  303 ,  305  of planetary gears  117 ,  127 ,  137 . From each mounting  301 ,  303 ,  305 , varying the width of the planetary gears  117 ,  127  of the first planetary stage  103  and the second planetary stage  105 , results in two different transmissions. 
     The first mounting  301  provides a transmission  101  having five planetary gears  117  in the first planetary stage  103 , five planetary gears  127  in the second planetary stage  105  and three planetary gears  137  in the third planetary stage  107 . The set  301  includes two transmissions  101  with the first mounting  301 . These differ by the width of the planetary gears  117  of the first planetary stage  103  and the planetary gears  127  of the second planetary stage  105  such that both the planetary gears  117  of the first planetary stage  103  and the planetary gears  127  of the second planetary stage  105  have a narrower design in one of the two transmissions than they have in the other. The third planetary stages  107  of the two transmissions are identical in construction. 
     The second mounting  303  provides a transmission  101  having six planetary gears  117  in the first planetary stage  103 , six planetary gears  127  in the second planetary stage  105 , and four planetary gears  137  in the third planetary stage  107 . The set  301  contains two transmissions  101  with the second mounting  303 . These differ by the width of the planetary gears  117  of the first planetary stage  103  and the planetary gears  127  of the second planetary stage  105  such that both the planetary gears  117  of the first planetary stage  103  and the planetary gears  127  of the second planetary stage  105  have a narrower design in one of the two transmissions than they have in the other. The third planetary stages  107  of the two transmissions are identical in construction. 
     The third mounting  305  provides a transmission  101  having seven planetary gears  117  in the first planetary stage  103 , seven planetary gears  127  in the second planetary stage  105 , and five planetary gears  137  in the third planetary stage  107 . The set  301  includes two transmissions  101  with the third mounting  305 . These differ by the width of the planetary gears  117  of the first planetary stage  103  and the planetary gears  127  of the second planetary stage  105  such that both the planetary gears  117  of the first planetary stage  103  and the planetary gears  127  of the second planetary stage  105  have a narrower design in one of the two transmissions than they have in the other. The third planetary stages  107  of the two transmissions are identical in construction. 
     While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. It will be understood that changes and modifications may be made by those of ordinary skill within the scope of the following claims. In particular, the present invention covers further embodiments with any combination of features from different embodiments described above and below. 
     The terms used in the claims should be construed to have the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article “a” or “the” in introducing an element should not be interpreted as being exclusive of a plurality of elements. Likewise, the recitation of “or” should be interpreted as being inclusive, such that the recitation of “A or B” is not exclusive of “A and B,” unless it is clear from the context or the foregoing description that only one of A and B is intended. Further, the recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise. Moreover, the recitation of “A, B and/or C” or “at least one of A, B or C” should be interpreted as including any singular entity from the listed elements, e.g., A, any subset from the listed elements, e.g., A and B, or the entire list of elements A, B and C. 
     LIST OF REFERENCE CHARACTERS 
       101  Transmission 
       103  First planetary stage 
       105  Second planetary stage 
       107  Third planetary stage 
       109  Input shaft 
       111  Output shaft 
       113  Planetary carrier 
       115  Ring gear 
       117  Planetary gear 
       119  Sun gear 
       121  Intermediate shaft 
       123  Planetary carrier 
       125  Ring gear 
       127  Planetary gear 
       129  Sun gear 
       131  Intermediate shaft 
       133  Planetary carrier 
       135  Ring gear 
       137  Planetary gear 
       139  Sun gear 
       301  First mounting 
       303  Second mounting 
       305  Third mounting