Patent Publication Number: US-2017350486-A1

Title: Power shift transmission for an agricultural machine

Description:
This application claims priority from German patent application serial no. 10 2016 209 942.6 filed Jun. 7, 2016. 
     FIELD OF THE INVENTION 
     The invention concerns a powershift transmission for agricultural machines. 
     BACKGROUND OF THE INVENTION 
     DE 10 2010 061 919 A1 discloses a powershift transmission for agricultural machines, with a splitter group designed for powershifting by means of friction clutches. 
     SUMMARY OF THE INVENTION 
     The purpose of the present invention is to develop further powershift transmissions for agricultural machines having a powershiftable splitter group, in such manner that they can be constructed simply and inexpensively for the application for which they are intended, 
     This objective is achieved with a powershift transmission for agricultural machines, of the type concerned, which also embodies the characterizing features specified in the principal claim. 
     According to the invention, the powershift transmission for agricultural machines comprises a first transmission part in the form of a splitter group, which cooperates with a second transmission part in the form of a multi-speed transmission such that the second transmission part in the form of a multi-speed transmission has shiftable forward gears and at least one shiftable reversing gear, and the splitter group in the first transmission part is designed for powershifting and cooperates with the gearwheels and clutches in such manner that the rotational direction of the output shaft of the splitter group remains the same regardless of the gear ratio engaged in the splitter group. This makes it possible to connect to the output shaft of the splitter group, a standard multi-speed transmission, which can be designed in accordance with the driving speed and traction force needs to suit the agricultural machine concerned, for example a tractor. 
     In a further development of the invention it is possible to design the multi-speed transmission so that its shifts can be automated and/or are completely powershiftable. By designing the powershiftable splitter group and the multi-speed transmission as independent components of the powershift transmission, a modular assembly can be produced whose modules can be combined according to need. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further characteristics emerge from the description of the figures, which show. 
         FIG. 1 . A powershift transmission with a first part and a second part; 
         FIG. 2 : A powershift transmission with a first part and a second part; and 
         FIG. 3 : A powershift transmission with a first part and a second part. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1 : 
     The powershift transmission consists of a first part  1  and a second part  2 . 
     The first part  1  comprises a powershiftable splitter group  3  and the second part  2  comprises a multispeed transmission  4 . The multispeed transmission  4  has a number of gears that can be engaged for forward driving and a number of gears that can be engaged for driving in reverse. The input shaft  5  of the splitter group  3  can be connected to a drive motor, for example an internal combustion engine. A spur gear  6  is connected coaxially and in a rotationally fixed manner to the input shaft  5 . On the input shaft  5 , a spur gear  7  is fitted and able to rotate. A spur gear  9  is connected coaxially and in a rotationally fixed manner to the output shaft  8 . A spur gear  10  is fitted and able to rotate on the output shaft  8 . By means of a clutch  11  the spur gear  10  can be connected to a spur gear  15 . By means of a clutch  12  the output shaft can be connected to the spur gear  15 . By means of a clutch  14  the spur gear  6  can be connected to a spur gear  16 . By means of a clutch  13  the spur gear  7  can be connected to the spur gear  16 . The spur gear  6  is in meshing connection with the spur gear  10 . The spur gear  7  is in meshing connection with the spur gear  9  and the spur gear  15  is in meshing connection with the spur gear  16 . By actuating the clutch  14  in the closing direction, actuating the clutch  13  in the opening direction and actuating the clutch  12  in the closing direction, the rotation of the input shaft  5  is transmitted to the output shaft  8 . By actuating the clutches  13  and  14  in the closing direction and actuating the clutches  11  and  12  in the opening direction, a further gear is engaged. By actuating the clutch  14  in the opening direction, the clutch  11  in the closing direction, the clutch  13  in the closing direction and the clutch  12  in the opening direction, another gear is engaged. By actuating the clutches  11  and  12  in the closing direction and the clutches  13  and  14  in the opening direction a further gear is engaged. During the gearshifts the rotational direction of the input shaft  5  and the output shaft  8  remains unchanged. The multi-speed transmission  4  has friction clutches  17  and shifting elements  18 , such that by means of the shifting elements  18  the various gear ratios are engaged. Since the rotational direction of the input shaft  5  and the output shaft  8  always remains the same, standard multi-speed transmissions can be connected to the output shaft  8 . For that purpose the multi-speed transmission  4  has a drive input shaft  19 , which is connected in a rotationally fixed manner to the output shaft  8  or is made integrally therewith. Furthermore, the multi-speed transmission  4  has a drive output shaft  20  which, for example, can be connected to a rear axle of a tractor. 
       FIG. 2 : 
     The first part of  FIG. 2  is identical to the first part of  FIG. 1 . In the multi-speed transmission  4  shifts are made between various gear ratios by means of a shifting element  21  and the reversing gears are engaged by means of the shifting element  22 . By virtue of the friction clutches  17  additional powershifts can be carried out. 
       FIG. 3 : 
     The first part of  FIG. 3  is identical to the first part  1  of  FIG. 1 . The multi-speed transmission  4  has friction clutches  17  and shifting elements  18  by means of which various gear ratios can be engaged. These gear ratios can be engaged in the forward driving direction by means of the clutch  23  and in the reverse driving direction by means of the crutch  24 . 
     INDEXES 
     
         
           1  First part 
           2  Second part 
           3  Sputter group 
           4  Multispeed transmission 
           5  Input shaft 
           6  Spur gear 
           7  Spur gear 
           8  Output shaft 
           9  Spur gear 
           10  Spur gear 
           11  Clutch 
           12  Clutch 
           13  Clutch 
           14  Clutch 
           15  Spur gear 
           16  Spur gear 
           17  Friction clutch 
           18  Shifting element 
           19  Drive input shaft 
           20  Drive output shaft 
           21  Shifting element 
           22  Shifting element 
           23  Clutch 
           24  Clutch