Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application is a divisional application of U.S. patent application Ser. No. 11/746,396, filed May 9, 2007, which, in turn, claims the benefit of U.S. provisional patent application Ser. No. 60/895,411, filed on Mar. 16, 2007. The disclosure of the above application is incorporated herein by reference. 
    
    
     FIELD 
     The invention relates generally to a multiple speed transmission having a plurality of planetary gear sets and a plurality of torque transmitting devices and more particularly to a transmission having eight or more speeds, four planetary gear sets and a plurality of torque transmitting devices. 
     BACKGROUND 
     The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art. 
     A typical multiple speed transmission uses a combination of a plurality of torque transmitting mechanisms, planetary gear arrangements and fixed interconnections to achieve a plurality of gear ratios. The number and physical arrangement of the planetary gear sets, generally, are dictated by packaging, cost and desired speed ratios. 
     While current transmissions achieve their intended purpose, the need for new and improved transmission configurations which exhibit improved performance, especially from the standpoints of efficiency, responsiveness and smoothness and improved packaging, primarily reduced size and weight, is essentially constant. Accordingly, there is a need for an improved, cost-effective, compact multiple speed transmission. 
     SUMMARY 
     A transmission is provided having an input member, an output member, a plurality of planetary gear sets, and a plurality of torque-transmitting mechanisms. The plurality of planetary gear sets each have a sun gear member, a planetary carrier member, and a ring gear member. 
     In one aspect of the present invention, four of the gear sets are simple planetary gear sets. 
     In another aspect of the present invention, two of the plurality of torque transmitting mechanisms are brakes. 
     In another aspect of the present invention, three of the torque transmitting mechanisms are friction clutches. 
     Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
         FIG. 1A  is a schematic diagram of a transmission according to the principles of the present invention; 
         FIG. 1B  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 1A ; 
         FIG. 1C  is a schematic diagram of another arrangement of the transmission according to the principles of the present invention; 
         FIG. 1D  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 1C ; 
         FIG. 2A  is a schematic diagram of still another arrangement of the transmission according to the principles of the present invention; 
         FIG. 2B  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 2A ; 
         FIG. 3A  is a schematic diagram of still another arrangement of the transmission according to the principles of the present invention; 
         FIG. 3B  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 3A ; 
         FIG. 4A  is a schematic diagram of still another arrangement of the transmission according to the principles of the present invention; 
         FIG. 4B  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 4A ; 
         FIG. 5A  is a schematic diagram of still another arrangement of the transmission according to the principles of the present invention; 
         FIG. 5B  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 5A ; 
         FIG. 6A  is a schematic diagram of still another arrangement of the transmission according to the principles of the present invention; 
         FIG. 6B  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 6A ; 
         FIG. 7A  is a schematic diagram of still another arrangement of the transmission according to the principles of the present invention; and 
         FIG. 7B  is a chart showing feasible locations of the torque transmitting devices for the arrangement of the transmission shown in  FIG. 7A . 
     
    
    
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. 
     Referring now to  FIG. 1A , an embodiment of a multi-speed or eight speed transmission is generally indicated by reference number  10 . The transmission  10  is illustrated as a rear-wheel drive or longitudinal transmission, though various other types of transmission configurations may be employed. The transmission  10  includes a transmission housing  11 , an input shaft or member  12 , and an output shaft or member  14 . The input member  12  is continuously connected to an engine (not shown) or to a turbine of a torque converter (not shown). The output member  14  is continuously connected with a final drive unit (not shown) or transfer case (not shown). 
     The transmission  10  includes a first planetary gear set  16 , a second planetary gear set  18 , a third planetary gear set  20 , and a fourth planetary gear set  22 . The planetary gear sets  16 ,  18 ,  20  and  22  are connected between the input member  12  and the output member  14 . In a preferred embodiment of the present invention, the planetary gear set  16  includes a sun gear member  24 , a ring gear member  26 , and a planet carrier member  28  that rotatably supports a set of planet or pinion gears  30  (only one of which is shown). The pinion gears  30  are configured to intermesh with the sun gear member  24  and the ring gear member  26 . The sun gear member  24  is connected for common rotation with a first shaft or intermediate member  32  and a second shaft or intermediate member  34 . It should be appreciated that the first intermediate member  32  is connected for common rotation with the second intermediate member  34  and that the intermediate members  32  and  34  may form one single shaft or multiple shafts through one or more members of the planetary gear sets, as seen throughout the several views. The ring gear member  26  is connected for common rotation with a third shaft or intermediate member  36 . The planet carrier member  28  is connected for common rotation with a fourth shaft or intermediate member  38 . 
     The planetary gear set  18  includes a sun gear member  42 , a ring gear member  44 , and a planet carrier member  46  that rotatably supports a set of planet or pinion gears  48 . The pinion gears  48  are configured to intermesh with the sun gear member  42  and the ring gear member  44 . The sun gear member  42  is connected for common rotation with the second intermediate member  34 . The ring gear member  44  is connected for common rotation with a fifth shaft or intermediate member  50 . The planet carrier member  46  is connected for common rotation with the input member  12 . 
     The planetary gear set  20  includes a sun gear member  52 , a ring gear member  54 , and a carrier member  56  that rotatably supports a set of planet or pinion gears  58 . The pinion gears  58  are configured to intermesh with the sun gear member  52  and the ring gear member  54 . The sun gear member  52  is connected for common rotation with the fifth shaft or intermediate member  50  and with a sixth shaft or intermediate member  51 . It should be appreciated that the fifth intermediate member  50  is connected for common rotation with the sixth intermediate member  51  and that the intermediate members  50  and  51  may form one single shaft or multiple shafts through one or more members of the planetary gear sets, as seen throughout the several views. The ring gear member  54  is connected for common rotation with a seventh shaft or intermediate member  60 . The planet carrier member  56  is connected for common rotation with an eighth shaft or intermediate member  62 . It should be appreciated that the eighth intermediate member  62  is connected for common rotation with the output member  14  and that the eighth intermediate members  62  and the output member  14  may form one single shaft or multiple shafts through one or more members of the planetary gear sets, as seen throughout the several views. 
     The planetary gear set  22  includes a sun gear member  72 , a ring gear member  74 , and a planet carrier member  76  that rotatably supports a set of planet or pinion gears  78 . The pinion gears  78  are configured to intermesh with the sun gear member  72  and the ring gear member  74 . The sun gear member  72  is connected for common rotation with a ninth shaft or intermediate member  64  and a tenth shaft or intermediate member  66 . It should be appreciated that the ninth intermediate member  64  is connected for common rotation with the tenth intermediate member  66  and that the intermediate members  64  and  66  may form one single shaft or multiple shafts through one or more members of the planetary gear sets, as seen throughout the several views. The ring gear member  74  is connected for common rotation with the fourth intermediate member  38 . The planet carrier member  76  is connected for common rotation with the output member  14  and with the eighth intermediate member  62 . 
     The transmission  10  includes a variety of torque-transmitting mechanisms or devices including a first intermediate clutch C 1 , a second intermediate clutch C 2 , a third intermediate clutch C 3 , a first brake B 1  and a second brake B 2 . The first intermediate clutch C 1  is selectively engagable to connect the input member  12  to the tenth intermediate member  66 . Alternatively, the first intermediate clutch C 1  may be connected to the input member  12  through the planet carrier member  46 , as seen throughout the several views. The second intermediate clutch C 2  is selectively engagable to connect the sixth intermediate member  51  to the ninth intermediate member  64 . The third intermediate clutch C 3  is selectively engagable to connect the seventh intermediate member  60  to the ninth intermediate member  64 . The brake B 1  is selectively engagable to connect the first intermediate member  32  to the transmission housing  11  to restrict rotation of the first intermediate member  32  relative to the transmission housing  11 . Finally, the brake B 2  is selectively engagable to connect the third intermediate member  36  to the transmission housing  11  to restrict rotation of the third intermediate member  36  relative to the transmission housing  11 . 
     The transmission  10  is capable of transmitting torque from the input member  12  to the output member  14  in at least eight forward torque ratios and one reverse torque ratio. Each of the forward torque ratios and the reverse torque ratio are attained by engagement of one or more of the torque-transmitting mechanisms (i.e. first intermediate clutch C 1 , second intermediate clutch C 2 , third intermediate clutch C 3 , brake B 1  and brake B 2 ). Those skilled in the art will readily understand that a different speed ratio is associated with each torque ratio. Thus, eight forward speed ratios may be attained by the transmission  10 . 
     The transmission housing  11  includes a first end wall  102 , a second end wall  104 , and a third wall  106 . The third wall  106  interconnects between the first and second end walls  102  and  104  to provide a space or cavity  108  in which planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are located. Further, the cavity  108  has a plurality of areas or Zones A, B, C, D, E, and F in which the plurality of torque transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  will be specifically positioned, in accordance with the preferred embodiments of the present invention. 
     As shown in  FIG. 1A  and throughout the several views, Zone A is defined by the area or space bounded: axially on the left by the first end wall  102 , on the right by planetary gear set  16 , radially inward by a reference line “L” which is a longitudinal line that is axially aligned with the input shaft  12 , and radially outward by a reference line “M” which is a longitudinal line that extends adjacent an outer diameter or outer periphery of the planetary gear sets  16 ,  18 ,  20 , and  22 . While reference line “M” is illustrated as a straight line throughout the several views, it should be appreciated that reference line “M” follows the outer periphery of the planetary gear sets  16 ,  18 ,  20 , and  22 , and accordingly may be stepped or non-linear depending on the location of the outer periphery of each of the planetary gear sets  16 ,  18 ,  20 , and  22 . Zone B is defined by the area bounded: axially on the left by planetary gear set  16 , axially on the right by the planetary gear set  18 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone C is defined by the area bounded: axially on the left by the planetary gear set  18 , axially on the right by the planetary gear set  20 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone D is defined by the area bounded: axially on the left by the planetary gear set  20 , axially on the right by the planetary gear set  22 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone E is defined by the area bounded: axially on the left by the planetary gear set  22 , axially on the right by the second end wall  104 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone F is defined by the area bounded: axially on the left by the first end wall  102 , axially on the right by the second end wall  104 , radially inward by reference line “M” and radially outward by the third wall  106 . As will be described and illustrated hereinafter, planetary gear sets  16 ,  18 ,  20 , and  22  will change positions within the transmission cavity  108 , however, the Zones described above will not change and will remain the same as shown throughout the Figures. 
     In the arrangement of the transmission  10  shown in  FIG. 1A , the planetary gear sets  16 ,  18 ,  20 , and  22  are longitudinally arranged in the following order from left to right:  16 - 18 - 20 - 22 . Specifically, the planetary gear set  16  is disposed closest to the wall  102 , the planetary gear set  22  is disposed closest to the wall  104 , the planetary gear set  18  is adjacent the planetary gear set  16 , and the planetary gear set  20  is disposed between the planetary gear sets  18  and  22 . The torque-transmitting mechanisms are intentionally located within specific Zones in order to provide advantages in overall transmission size, packaging efficiency, and reduced manufacturing complexity. In the particular example shown in  FIG. 1A , the torque-transmitting mechanism C 1  is disposed within Zone C, the torque-transmitting mechanisms C 2  and C 3  are disposed within Zone D, and the torque-transmitting mechanisms B 1  and B 2  are disposed within Zone F. 
     However, the present invention contemplates other embodiments where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 1B . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     With reference to  FIG. 1C , an alternate embodiment of the multi-speed transmission is indicated by reference number  10 B. The transmission  10 B includes the planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2 . The various components and connecting shafts that are identical with the transmission  10  in  FIG. 1A  have the same numerical designation. 
     The transmission  10 B includes the planetary gear sets  16 ,  18 ,  20 , and  22  longitudinally arranged identically to the arrangement shown in  FIG. 1A . However, in the particular example shown in  FIG. 1C , the torque-transmitting mechanisms C 1  and C 2  are disposed within Zone B. As in the previous embodiment, the torque-transmitting mechanism C 3  is disposed within Zone D and the torque-transmitting mechanisms B 1  and B 2  are disposed within Zone F. 
     Additionally, the present invention contemplates other embodiments of transmission  10 B where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 1D . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     Turning now to  FIG. 2A , still another embodiment of the multi-speed transmission is indicated by reference number  200 . The transmission  200  includes the planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2 . The various components and connecting shafts that are identical with the transmission  10  in  FIG. 1A  have the same numerical designation in  FIG. 2A . 
     The transmission  200  includes the planetary gear sets  16 ,  18 ,  20 , and  22  longitudinally arranged in the following order from left to right:  18 - 20 - 16 - 22 . Specifically, the planetary gear set  18  is disposed closest to the wall  102 , the planetary gear set  22  is disposed closest to the wall  104 , the planetary gear set  20  is adjacent the planetary gear set  18 , and the planetary gear set  16  is disposed between the planetary gear sets  20  and  22 . The torque-transmitting mechanisms are intentionally located within specific Zones in order to provide advantages in overall transmission size, packaging efficiency, and reduced manufacturing complexity. In the particular example shown in  FIG. 2A , the torque-transmitting mechanisms C 1  and C 2  are disposed within Zone A, the torque-transmitting mechanism C 3  is disposed within Zone C, and the torque-transmitting mechanisms B 1  and B 2  are disposed within Zone F. 
     However, the present invention contemplates other embodiments of the transmission  200  where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 2B . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     With reference to  FIG. 3A , still another embodiment of the multi-speed transmission is indicated by reference number  300 . The transmission  300  includes the planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2 . The various components and connecting shafts that are identical with the transmission  10  in  FIG. 1A  have the same numerical designation in  FIG. 3A . 
     The transmission  300  includes the planetary gear sets  16 ,  18 ,  20 , and  22  longitudinally arranged identically to the arrangement shown in  FIG. 2A . However, the input shaft  12  is arranged such that it crosses the boundary between Zones A and F. In the particular example shown in  FIG. 3A , the torque-transmitting mechanisms C 1  and C 2  are disposed within Zone A, the torque-transmitting mechanism C 3  is disposed within Zone C, and the torque-transmitting mechanisms B 1  and B 2  are disposed within Zone F. 
     However, the present invention contemplates other embodiments of the transmission  300  where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 3B . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     With reference to  FIG. 4A , still another embodiment of the multi-speed transmission is indicated by reference number  400 . The transmission  400  includes the planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2 . The various components and connecting shafts that are identical with the transmission  10  in  FIG. 1A  have the same numerical designation in  FIG. 4A . 
     The transmission  400  includes the planetary gear sets  16 ,  18 ,  20 , and  22  longitudinally arranged in the following order from left to right:  18 - 16 - 20 - 22 . Specifically, the planetary gear set  18  is disposed closest to the wall  102 , the planetary gear set  22  is disposed closest to the wall  104 , the planetary gear set  16  is adjacent the planetary gear set  18 , and the planetary gear set  20  is disposed between the planetary gear sets  16  and  22 . The torque-transmitting mechanisms are intentionally located within specific Zones in order to provide advantages in overall transmission size, packaging efficiency, and reduced manufacturing complexity. In the particular example shown in  FIG. 4A , the torque-transmitting mechanisms C 1  and C 2  are disposed within Zone A, the torque-transmitting mechanism C 3  is disposed within Zone C, and the torque-transmitting mechanisms B 1  and B 2  are disposed within Zone F. 
     However, the present invention contemplates other embodiments of the transmission  400  where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 4B . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     With reference to  FIG. 5A , still another embodiment of the multi-speed transmission is indicated by reference number  500 . The transmission  500  includes the planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2 . The various components and connecting shafts that are identical with the transmission  10  in  FIG. 1A  have the same numerical designation in  FIG. 5A . 
     The transmission  500  includes the planetary gear sets  16 ,  18 ,  20 , and  22  longitudinally arranged in the following order from left to right:  18 - 16 - 22 - 20 . Specifically, the planetary gear set  18  is disposed closest to the wall  102 , the planetary gear set  20  is disposed closest to the wall  104 , the planetary gear set  16  is adjacent the planetary gear set  18 , and the planetary gear set  22  is disposed between the planetary gear sets  16  and  20 . The torque-transmitting mechanisms are intentionally located within specific Zones in order to provide advantages in overall transmission size, packaging efficiency, and reduced manufacturing complexity. In the particular example shown in  FIG. 5A , the torque-transmitting mechanisms C 1  and C 2  are disposed within Zone A, the torque-transmitting mechanism C 3  is disposed within Zone D, and the torque-transmitting mechanisms B 1  and B 2  are disposed within Zone F. 
     However, the present invention contemplates other embodiments of the transmission  500  where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 5B . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     With reference to  FIG. 6A , still another embodiment of the multi-speed transmission is indicated by reference number  600 . The transmission  600  includes the planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2 . The various components and connecting shafts that are identical with the transmission  10  in  FIG. 1A  have the same numerical designation in  FIG. 6A . 
     The transmission  600  includes the planetary gear sets  16 ,  18 ,  20 , and  22  longitudinally arranged in the following order from left to right:  20 - 18 - 16 - 22 . Specifically, the planetary gear set  20  is disposed closest to the wall  102 , the planetary gear set  22  is disposed closest to the wall  104 , the planetary gear set  18  is adjacent the planetary gear set  20 , and the planetary gear set  16  is disposed between the planetary gear sets  18  and  22 . The torque-transmitting mechanisms are intentionally located within specific Zones in order to provide advantages in overall transmission size, packaging efficiency, and reduced manufacturing complexity. In the particular example shown in  FIG. 6A , the torque-transmitting mechanisms C 1 , C 2 , B 1 , and B 2  are disposed within Zone F, and the torque-transmitting mechanism C 3  is disposed within Zone A. 
     However, the present invention contemplates other embodiments of the transmission  600  where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 6B . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     With reference to  FIG. 7A , still another embodiment of the multi-speed transmission is indicated by reference number  700 . The transmission  700  includes the planetary gear sets  16 ,  18 ,  20 , and  22  and the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2 . The various components and connecting shafts that are identical with the transmission  10  in  FIG. 1A  have the same numerical designation in  FIG. 7A . 
     The transmission  700  includes the planetary gear sets  16 ,  18 ,  20 , and  22  longitudinally arranged in the following order from left to right:  20 - 22 - 18 - 16 . Specifically, the planetary gear set  20  is disposed closest to the wall  102 , the planetary gear set  16  is disposed closest to the wall  104 , the planetary gear set  22  is adjacent the planetary gear set  20 , and the planetary gear set  18  is disposed between the planetary gear sets  22  and  16 . The torque-transmitting mechanisms are intentionally located within specific Zones in order to provide advantages in overall transmission size, packaging efficiency, and reduced manufacturing complexity. In the particular example shown in  FIG. 7A , the torque-transmitting mechanisms C 1 , C 2 , and C 3  are disposed within Zone B, the torque-transmitting mechanism B 1  is disposed within Zone F, and the torque-transmitting mechanism B 2  is disposed within Zone E. 
     However, the present invention contemplates other embodiments of the transmission  700  where the torque-transmitting mechanisms C 1 , C 2 , C 3 , B 1 , and B 2  are disposed in the other Zones. The feasible locations of the torque-transmitting devices C 1 , C 2 , C 3 , B 1 , and B 2  relative to the Zones are illustrated in the chart shown in  FIG. 7B . An “X” in the chart indicates that the present invention contemplates locating the particular torque-transmitting device in any of the referenced Zones. 
     The description of the invention is merely exemplary in nature and variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

Technology Category: 2