Patent Publication Number: US-6656077-B2

Title: Family of multi-speed transmission mechanisms having input clutches and three planetary gearsets

Description:
TECHNICAL FIELD 
     This invention relates to multi-speed transmissions and, more particularly, to a family of transmissions having three planetary gearsets and five torque-transmitting mechanisms. 
     BACKGROUND OF THE INVENTION 
     Passenger vehicles include a powertrain that is comprised of an engine, multi-speed transmission, and a differential or final drive mechanism. The multi-speed transmission increases the overall operating range of the vehicle by permitting the engine to operate through its torque range a number of times as the transmission ratios are interchanged. The number of forward speed ratios that are available in a transmission determines the number of ratio interchanges that can occur and therefore the number of times the engine torque range can be repeated. 
     Early automatic transmissions had two speed ranges. This severely limited the overall speed range of the vehicle and therefore required a relatively large engine that could produce a wide speed and torque range. This resulted in the engine operating at a specific fuel consumption point, during cruising, other than the most efficient point. Therefore, manually shifted (countershaft transmissions) were the most popular. 
     With the advent of three and four speed automatic transmissions, the automatic shifting (planetary gear) transmission increased in popularity with the motoring public. These transmissions improve the operating performance and fuel economy of the vehicle. The increased number of speed ratios reduces the step size between ratios and therefore improves the shift quality of the transmission by making the ratio interchanges substantially imperceptible to the operator under normal vehicle acceleration. 
     It has been suggested that the number of forward speed ratios be increased to five and even six speeds. This has been accomplished in many heavy truck powertrains. Six speed transmissions are disclosed in U.S. Pat. No. 4,070,927 issued to Polak on Jan. 31, 1978; U.S. Pat. No. 5,106,352 issued to Lepelletier on Apr. 21, 1992; U.S. Pat. No. 5,542,889 issued to Pierce et al. on Aug. 6, 1996; U.S. Pat. No. 5,599,251 issued to Beim and McCarrick on Feb. 4, 1997; U.S. Pat. No. 6,071,208 issued to Koivunen on Jun. 6, 2000; U.S. Pat. No. 6,083,135 issued to Baldwin et al. on Jul. 4, 2000; and European Patent Application No. EP 1 033 510 A1 published Jun. 9, 2000. 
     Six speed transmissions offer several advantages over four and five speed transmissions, including improved vehicle acceleration and improved fuel economy. While many trucks employ six-speed transmissions, such as Polak, passenger cars are still manufactured, for the main part, with three and four speed automatic transmissions, and relatively few five or six speed devices due to the size and complexity of these transmissions. The Polak transmission provides six forward speed ratios with three planetary gearsets, two clutches, and three brakes. The Koivunen and Beim patents utilize six torque transmitting devices including four brakes and two clutches to establish the six forward speed ratios and one reverse ratio. The Lepelletier and the EP publications each employ three planetary gearsets, three clutches and two brakes to provide six forward speed ratios and one reverse ratio. One of the planetary gearsets in each of these publications is positioned and operated to establish two fixed speed input members for the remaining two planetary gearsets. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an improved family of six-speed planetary transmissions having five torque-transmitting mechanisms and three planetary gearsets. 
     In one aspect of the present invention, each of the three planetary gearsets has three members comprising any one of a sun gear member, a ring gear member, or a planet carrier assembly member. 
     In another aspect of the present invention, the planet carrier assembly member may be either a single pinion or double pinion planetary assembly member. 
     In another aspect of the present invention, the first member of the first planetary gearset is continuously interconnected through an interconnecting member with a first member of the second planetary gearset. 
     In yet another aspect of the present invention, a second interconnecting member continuously interconnects a first member of the third planetary gearset with either the first or second member of the second planetary gearset. 
     In still another aspect of the present invention, the second member of the first planetary gearset, or the third member of the second planetary gearset, is continuously connected with a stationary member of the transmission, such as a transmission housing. 
     In yet still another aspect of the present invention, the transmission output shaft is continuously connected with at least one member of one of the planetary gearsets. 
     In a further aspect of the present invention, a first of the torque-transmitting mechanisms connects an input shaft of the transmission with at least one member of one of the planetary gearsets. 
     In yet a further aspect of the present invention, a second of the torque-transmitting mechanisms selectively interconnects the input shaft with another member of the one of the planetary gearsets or with one of the interconnecting members. 
     In a still further aspect of the present invention, a third of the torque-transmitting mechanisms selectively interconnects a member of the planetary gearsets with the input shaft or another member of one of the planetary gearsets. 
     In a yet still further aspect of the present invention, a fourth of the torque-transmitting mechanisms selectively interconnects a member of the first second or third planetary gearset with another member of the planetary gearsets. 
     In another aspect of the present invention, a fifth of the torque-transmitting mechanisms operates as either a clutch or a brake to selectively interconnect a member of one of the planetary gearsets with the output shaft, or another member of one of the planetary gearsets, or selectively interconnects a member of one of the planetary gearsets with the transmission housing. 
     In a further aspect of the present invention, the five torque-transmitting mechanisms are selectively actuated in combinations of three to establish at least six forward speed ratios and one reverse speed ratio between the transmission input shaft and the transmission output shaft. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic representation of a powertrain incorporating one of the family members of the present invention. 
     FIG. 2 is a truth table and chart depicting some of the operating characteristics of the transmission family member shown in FIG.  1 . 
     FIG. 3 is a schematic representation of a powertrain incorporating another family of the present invention. 
     FIG. 4 is a truth table and chart depicting some of the operating characteristics of the family member shown in FIG.  3 . 
     FIG. 5 is a schematic representation of a powertrain incorporating another family of the present invention. 
     FIG. 6 is a truth table and chart depicting some of the operating characteristics of the family member shown in FIG.  5 . 
     FIG. 7 is a schematic representation of a powertrain incorporating another family of the present invention. 
     FIG. 8 is a truth table and chart depicting some of the operating characteristics of the family member shown in FIG.  7 . 
     FIG. 9 is a schematic representation of a powertrain incorporating another family of the present invention. 
     FIG. 10 is a truth table and chart depicting some of the operating characteristics of the family member shown in FIG.  9 . 
     FIG. 11 is a schematic representation of a powertrain incorporating another family of the present invention. 
     FIG. 12 is a truth table and chart depicting some of the operating characteristics of the family member shown in FIG.  11 . 
    
    
     DESCRIPTION EXEMPLARY EMBODIMENTS 
     Referring to the drawings, wherein like characters represent the same or corresponding parts throughout the several views, there is seen in FIG. 1 a powertrain  10 , having a conventional engine and torque converter  12 , a planetary transmission  14 , and a conventional final drive mechanism  16 . The planetary transmission  14  includes an input shaft  17 , a planetary gear arrangement  18 , and an output shaft  19 . The planetary gear arrangement  18  includes three planetary gearsets  20 ,  30 , and  40 , and five torque-transmitting mechanisms  50 ,  52 ,  54 ,  56 , and  58 . 
     The planetary gearset  20  includes a sun gear member  22 , a ring gear member  24 , and a planet carrier assembly member  26 . The planet carrier assembly member  26  includes a plurality of pinion gears  27  rotatably mounted on a planet carrier  29  and disposed in meshing relationship with both the sun gear member  22  and the ring gear member  24 . 
     The planetary gearset  30  includes a sun gear member  32 , a ring gear member  34 , and a planet carrier assembly member  36 . The planet carrier assembly member  36  includes a plurality of pinion gears  37  rotatably mounted on a planet carrier  39  and disposed in meshing relationship with both the sun gear member  32  and the ring gear member  34 . 
     The planetary gearset  40  includes a sun gear member  42 , a ring gear member  44 , and a planet carrier assembly member  46 . The planet carrier assembly member  46  includes a plurality of pinion gears  47  rotatably mounted on a planet carrier  49  and disposed in meshing relationship with both the sun gear member  42  and the ring gear member  44 . 
     Each of the planetary gearsets  20 ,  30 , and  40  shows only a single pinion gear, however, as is well known in the art, the planet carrier of each of the planet carrier assembly members will support a plurality of pinion gear members, usually three or four, depending on the torque loads that are to be encountered in the planetary gearset. The torque-transmitting mechanisms  50 ,  52 ,  54 , and  56  are rotating type torque-transmitting mechanisms, commonly termed clutches. The torque-transmitting mechanism  58  is a stationary type torque-transmitting mechanism, commonly termed a brake. 
     The planet carrier assembly member  26  and the planet carrier assembly member  36  are continuously interconnected by an interconnecting member  70 . The planet carrier assembly member  36  and the ring gear member  44  are continuously interconnected by an interconnecting member  72 . The sun gear member  22  is continuously connected with a transmission housing  60 . The sun gear member  42  is continuously connected with the output shaft  19 . 
     The input shaft  17  is selectively connectible with the sun gear member  32  through the torque-transmitting mechanism  50 , and selectively connectible with the planet carrier assembly member  46  through the torque-transmitting mechanism  52 . The sun gear member  32  and ring gear member  24  are selectively interconnectible through the torque-transmitting mechanism  54 . The planet carrier assembly member  46  and the ring gear member  34  are selectively interconnectible through the torque-transmitting mechanism  56 . The ring gear member  34  is selectively connectible with the transmission housing  60  through the torque-transmitting mechanism  58 . 
     As seen in the truth table of FIG. 2, the torque-transmitting mechanisms are engaged in combinations of three to establish six forward speed ratios and one reverse speed ratio between the input shaft  17  and the output shaft  19  through the planetary gear arrangement  18 . Also given in the truth table is a numerical example of the speed ratios that are available through the planetary gear arrangement  18  when the ring gear/sun gear tooth ratios of the planetary gearsets  20 ,  30 , and  40  are equal to the example ring gear/sun gear tooth ratios given as R 1 /S 1 , R 2 /S 2 , and R 3 /S 3 , respectively. 
     Further information provided in FIG. 2 is the ratio steps between adjacent forward speed ratios as well as the ratio step between the reverse and first forward speed ratio. 
     As will be noted from the truth table, each of the single step forward interchanges is of the single transition variety, and each of the double step forward interchanges is of the single transition variety. That is, on an interchange from first-to-second ratios, only a single torque-transmitting mechanism is swapped. For example, again on the first-to-second interchange, the torque-transmitting mechanisms  50  and  52  are swapped while the torque-transmitting mechanisms  54  and  56  remain engaged. 
     The reverse speed ratio is established with the engagement of the torque-transmitting mechanisms  50 ,  56 , and  58 . This combination of engagements connects the input shaft  17  with the sun gear member  32 , and the ring gear member  34  and planet carrier assembly member  46  with the transmission housing  60 . The planet carrier assembly member  36  and ring gear member  44  are rotated at a speed determined by the speed of the sun gear member  32  and the ring gear/sun gear tooth ratio of the planetary gearset  30 . The sun gear member  42  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  44  and the ring gear/sun gear tooth ratio of the planetary gearset  40 . The numerical value of the reverse speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  30  and  40 . 
     The first forward speed ratio is established with the engagement of the torque-transmitting mechanisms  50 ,  54 , and  56 . During the first forward speed ratio, the sun gear member  32  and the ring gear member  24  are driven by the input shaft  17 . The sun gear member  22  is held stationary continuously by the transmission housing  60 . The planet carrier assembly member  26 , the planet carrier assembly member  36 , and ring gear member  44  are rotated at a speed determined by the speed of the ring gear member  24  and the ring gear/sun gear tooth ratio of the planetary gearset  20 . The ring gear member  34  and planet carrier assembly member  46  are rotated at a speed determined by the speed of the sun gear member  32 , the speed of the planet carrier assembly member  36 , and the ring gear/sun gear tooth ratio of the planetary gearset  30 . The sun gear member  42  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  44 , the speed of the planet carrier assembly member  46 , and the ring gear/sun gear tooth ratio of the planetary gearset  40 . The numerical value of the first forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  20 ,  30 , and  40 . 
     The second forward speed ratio is established with the engagement of the torque-transmitting mechanisms  52 ,  54 , and  56 . During the second forward speed ratio, the planet carrier assembly member  46  and ring gear member  34  are rotated in unison with the input shaft  17 . The sun gear member  32  and ring gear member  24  are rotated at a speed determined by the speed of the ring gear member  34 , the speed of the planet carrier assembly member  36 , and the ring gear/sun gear tooth ratio of the planetary gearset  30 . The planet carrier assembly member  26 , planet carrier assembly member  36 , and ring gear member  44  are rotated at a speed determined by the speed of the ring gear member  24  and the ring gear/sun gear tooth ratio of the planetary gearset  20 . The sun gear member  42  and therefore output shaft  19  are rotated at a speed determined by the speed of the planet carrier assembly member  46 , the speed of the ring gear member  44 , and the ring gear/sun gear tooth ratio of the planetary gearset  40 . The numerical value of the second forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  20 ,  30 , and  40 . 
     The third forward speed ratio is established with the engagement of the torque-transmitting mechanisms  50 ,  52 , and  56 . During the third forward speed ratio, the sun gear member  32 , planet carrier assembly member  46 , and ring gear member  34 , are all driven by the input shaft  17  directly. This results in the planetary gearsets  30  and  40  rotating in unison with the input shaft  17 , such that the output shaft  19  also rotates in unison with the input shaft  17  and therefore the third forward speed ratio is a direct drive having a numerical value of one. 
     The fourth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  50 ,  52 , and  54 . During the fourth forward speed ratio, the sun gear member  32 , ring gear member  24 , and planet carrier assembly member  46 , are all rotated in unison with the input shaft  17 . The planet carrier assembly member  26 , planet carrier assembly member  36 , and ring gear member  44  are rotated at a speed determined by the speed of the ring gear member  24  and the ring gear/sun gear tooth ratio of the planetary gearset  20 . The sun gear member  42  and therefore output shaft  19  are rotated at a speed determined by the speed of the planet carrier assembly member  46 , the speed of the ring gear member  44 , and the ring gear/sun gear tooth ratio of the planetary gearset  40 . The numerical value of the fourth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  20  and  40 . 
     The fifth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  50 ,  52 , and  58 . During the fifth forward speed ratio, the sun gear member  32  and planet carrier assembly member  46  are rotated in unison with the input shaft  17 . The ring gear member  34  is held stationary by the torque-transmitting mechanism  58 . The planet carrier assembly member  36  and ring gear member  44  are rotated at a speed determined by the speed of the sun gear member  32  and the ring gear/sun gear tooth ratio of the planetary gearset  30 . The sun gear member  42  and therefore output shaft  19  are rotated at a speed determined by the speed of the planet carrier assembly member  46 , the speed of the ring gear member  44 , and the ring gear/sun gear tooth ratio of the planetary gearset  40 . The numerical value of the fifth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  30  and  40 . 
     The sixth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  52 ,  54 , and  58 . During the sixth forward speed ratio, the planet carrier assembly member  46  is rotated in unison with the input shaft  17  and the ring gear member  34  is held stationary. The ring gear member  24  and sun gear member  32  are rotated at a speed determined by the speed of the planet carrier assembly member  26  and the ring gear/sun gear tooth ratio of the planetary gearset  20 . The planet carrier assembly member  26 , planet carrier assembly member  36 , and ring gear member  44  are rotated at a speed determined by the speed of the sun gear member  32  and the ring gear/sun gear tooth ratio of the planetary gearset  30 . The sun gear member  42  and therefore output shaft  19  are rotated at a speed determined by the speed of the planet carrier assembly member  46 , the speed of the ring gear member  44 , and the ring gear/sun gear tooth ratio of the planetary gearset  40 . The numerical value of the sixth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  20 ,  30 , and  40 . 
     It should be noted that the ring gear member  24 , sun gear member  32 , ring gear member  34 , and planet carrier assembly member  46  are not continuously interconnected with other members of the planetary gear arrangement  18  except through the torque-transmitting mechanisms. These members are all termed as noncontinuously connected members. 
     A powertrain  110 , shown in FIG. 3, includes the conventional engine and torque converter  12 , a planetary transmission  114 , and the final  10  drive mechanism  16 . The planetary transmission  114  includes the input shaft  17 , a planetary gear arrangement  118 , and the output shaft  19 . The planetary gear arrangement  118  includes three planetary gearsets  120 ,  130 , and  140 , and five torque-transmitting mechanisms  150 ,  152 ,  154 ,  156 , and  158 . All of the torque-transmitting mechanisms are of the rotating type. 
     The planetary gearset  120  includes a sun gear member  122 , a ring gear member  124 , and a planet carrier assembly member  126 . The planet carrier assembly member  126  includes a plurality of pinion gears  127  rotatably mounted on a planet carrier  129  and disposed in meshing relationship with both the sun gear member  122  and the ring gear member  124 . 
     The planetary gearset  130  includes a sun gear member  132 , a ring gear member  134 , and a planet carrier assembly member  136 . The planet carrier assembly member  136  includes a plurality of pinion gears  137  rotatably mounted on a planet carrier  139  and disposed in meshing relationship with both the sun gear member  132  and the ring gear member  134 . 
     The planetary gearset  140  includes a sun gear member  142 , a ring gear member  144 , and a planet carrier assembly member  146 . The planet carrier assembly member  146  includes a plurality of pinion gears  147  rotatably mounted on a planet carrier  149  and disposed in meshing relationship with both the sun gear member  142  and the ring gear member  144 . 
     The sun gear member  122  and ring gear member  134  are continuously interconnected by an interconnecting member  170 . The sun gear member  132  and sun gear member  142  are continuously interconnected by an interconnecting member  172 . The output shaft  19  is continuously connected with the planet carrier assembly member  146 . The planet carrier assembly member  136  is continuously connected with the transmission housing  60 . 
     The input shaft  17  is selectively connectible with the planet carrier assembly member  126  through the torque-transmitting mechanism  150 , and selectively connectible with the ring gear member  144  through the torque-transmitting mechanism  152 . The planet carrier assembly member  126  is selectively interconnectible with the interconnecting member  170  through the torque-transmitting mechanism  154 . The ring gear member  124  is selectively interconnectible with the interconnecting member  172  through the torque-transmitting mechanism  156 . The ring gear member  124  is also selectively connectible with the output shaft  19  through the torque-transmitting mechanism  158 . 
     As seen in FIG. 4, the torque-transmitting mechanisms  150 ,  152 ,  154 ,  156 , and  158  are selectively connected in combinations of three to establish six forward speed ratios and one reverse speed ratio between the input shaft  17  and the output shaft  19  through the planetary gear arrangement  118 . Those skilled in the art will recognize that each of the single step and double step forward interchanges are of the single transition variety. The truth table of FIG. 4 also provides a numerical example of the speed ratios that are available in the planetary gear arrangement  118  when the ring gear/sun gear tooth ratios of the planetary gearsets  120 ,  130 , and  140  are equal to those given as R 1 /S 1 , R 2 /S 2 , and R 3 /S 3 , respectively. Also given in FIG. 4 is the numerical value of the ratio steps between adjacent forward speed ratios as well as between the reverse and first forward speed ratio. 
     The reverse speed ratio is established with the engagement of the torque-transmitting mechanisms  150 ,  152 , and  154 . During the reverse speed ratio, the planetary gearset  120  and ring gear member  134  are rotated in unison with the input shaft  17  as is the ring gear member  144 . The sun gear members  132  and  142  are rotated at a speed determined by the speed of the ring gear member  134  and the ring gear/sun gear tooth ratio of the planetary gearset  130 . The planet carrier assembly member  146  and therefore output shaft  19  are rotated at a speed determined by the speed of the sun gear member  142 , the speed of the ring gear member  144 , and the ring gear/sun gear tooth ratio of the planetary gearset  140 . The numerical value of the reverse speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  130  and  140 . 
     The first forward speed ratio is established with the engagement of the torque-transmitting mechanisms  152 ,  154 , and  158 . During the first forward speed ratio, the planetary gearset  120 , the ring gear member  134 , and the planet carrier assembly member  146  rotate in unison with the output shaft  19 . The sun gear members  132  and  142  are rotated at a speed determined by the speed of the ring gear member  144 , the speed of the planet carrier assembly member  146 , and the ring gear/sun gear tooth ratio of the planetary gearset  140 . The ring gear member  134 , and therefore the planet carrier assembly member  146 , and output shaft  19  are rotated at a speed determined by the speed of the sun gear member  132  and the ring gear/sun gear tooth ratio of the planetary gearset  130 . The numerical value of the first forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  130  and  140 . 
     The second forward speed ratio is established with the engagement of the torque-transmitting mechanisms  152 ,  154 , and  156 . During the second forward speed ratio, the planetary gearsets  120  and  130 , and sun gear member  142  are held stationary. The planet carrier assembly member  146  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  144  and the ring gear/sun gear tooth ratio of the planetary gearset  140 . The numerical. value of the second forward speed ratio is determined by the ring gear/sun gear tooth ratio of the planetary gearset  140 . 
     The third forward speed ratio is established with the engagement of the torque-transmitting mechanisms  152 ,  156 , and  158 . During the third forward speed ratio, the planetary gearset  140  and therefore output shaft  19  are driven in unison with the input shaft  17  resulting in a direct drive for the third forward speed ratio having a numerical value of one. 
     The fourth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  150 ,  152 , and  156 . During the fourth forward speed ratio, the sun gear member  122  and ring gear member  134  are rotated at a speed determined by the speed of the planet carrier assembly member  126 , the speed of the ring gear member  124 , and the ring gear/sun gear tooth ratio of the planetary gearset  120 . The sun gear members  132  and  142 , and ring gear member  124  are rotated at a speed determined by the speed of the ring gear member  134  and the ring gear/sun gear tooth ratio of the planetary gearset  130 . The planet carrier assembly member  146  and therefore output shaft  19  are rotated at a speed determined by the speed of the sun gear member  142 , the speed of the ring gear member  144 , and the ring gear/sun gear tooth ratio of the planetary gearset  140 . The numerical value of the fourth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  120 ,  130 , and  140 . 
     The fifth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  150 ,  156 , and  158 . During the fifth forward speed ratio, the sun gear member  122  and ring gear member  134  are rotated at a speed determined by the speed of the planet carrier assembly member  126 , the speed of the ring gear member  124 , and the ring gear/sun gear tooth ratio of the planetary gearset  120 . The sun gear members  132  and  142 , ring gear member  124 , planet carrier assembly member  146 , and output shaft  19  are rotated at a speed determined by the speed of the ring gear member  134  and the ring gear/sun gear tooth ratio of the planetary gearset  130 . The numerical of the fifth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  120  and  130 . 
     The sixth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  150 ,  152 , and  158 . During the sixth forward speed ratio, the sun gear member  122 , and ring gear member  134  are rotated at a speed determined by the speed of the planet carrier assembly member  126 , the speed of the ring gear member  124 , and the ring gear/sun gear tooth ratio of the planetary gearset  120 . The sun gear members  132  and  142  are rotated at a speed determined by the speed of the ring gear member  134  and the ring gear/sun gear tooth ratio of the planetary gearset  130 . The planet carrier assembly member  146  and therefore output shaft  19  are rotated at a speed determined by the speed of the sun gear member  142 , the speed of the ring gear member  144 , and the ring gear/sun gear tooth ratio of the planetary gearset  140 . The numerical value of the sixth forward speed ratio is established by the ring gear/sun gear tooth ratios of all three planetary gearsets  120 ,  130 , and  140 . 
     The planet carrier assembly member  126 , ring gear member  124 , and ring gear member  144 , are noncontinuously connected members of the planetary gear arrangement  118 . 
     A powertrain  210 , shown in FIG. 5, includes the engine and torque converter  12 , a planetary transmission  214 , and the final drive mechanism  16 . The planetary transmission  214  includes the input shaft  17 , a planetary gear arrangement  218 , and the output shaft  19 . The planetary gear arrangement  218  includes three planetary gearsets  220 ,  230 , and  240 , and five rotating type torque-transmitting mechanisms  250 ,  252 ,  254 ,  256 , and  258 . 
     The planetary gearset  220  includes a sun gear member  222 , a ring gear member  224 , and a planet carrier assembly member  226 . The planet carrier assembly member  226  includes a plurality of pinion gears  227  rotatably mounted on a planet carrier  229  and disposed in meshing relationship with both the sun gear member  222  and the ring gear member  224 . 
     The planetary gearset  230  includes a sun gear member  232 , a ring gear member  234 , and a planet carrier assembly member  236 . The planet carrier assembly member  236  includes a plurality of pinion gears  237  rotatably mounted on a planet carrier  239  and disposed in meshing relationship with both the sun gear member  232  and the ring gear member  234 . 
     The planetary gearset  240  includes a sun gear member  242 , a ring gear member  244 , and a planet carrier assembly member  246 . The planet carrier assembly member  246  includes a plurality of pinion gears  247  rotatably mounted on a planet carrier  249  and disposed in meshing relationship with both the sun gear member  242  and the ring gear member  244 . 
     The sun gear member  222  and sun gear member  232  are continuously interconnected by an interconnecting member  270 . The ring gear member  234  and sun gear member  242  are continuously interconnected by an interconnecting member  272 . The planet carrier assembly member  226  is continuously connected with the output shaft  19 . The planet carrier assembly member  236  is continuously connected with the transmission housing  60 . The ring gear member  244 , the planet carrier assembly member  246 , and the ring gear member  224  are noncontinuously interconnected members. 
     The input shaft  17  is selectively connectible with the ring gear member  224  through the torque-transmitting mechanism  250 , and selectively connectible with the planet carrier assembly member  246  through the torque-transmitting mechanism  252 . The ring gear member  244  is selectively connectible with the interconnecting member  270  through the torque-transmitting mechanism  254 , selectively connectible with the output shaft  19  through the torque-transmitting mechanism  256 , and selectively connectible with the planet carrier assembly member  246  through the torque-transmitting mechanism  258 . 
     The truth table of FIG. 6 describes the engagement of the torque-transmitting mechanisms to establish six forward speed ratios and one reverse speed ratio between the input shaft  17  and the output shaft  19  through the planetary gear arrangement  218 . Also given in the truth table of FIG. 6 is an example of the numerical values for the speed ratios when the ring gear/sun gear tooth ratios of the planetary gearsets  220 ,  230 , and  240  are as given in R 1 /S 1 , R 2 /S 2 , and R 3 /S 3 , respectively. Also given in FIG. 6 is the ratio steps between adjacent forward speed ratios as well as between the reverse and first forward speed ratio. As will be noted in the truth table, each of the single step forward interchanges and the double step forward interchanges are of the single transition variety. 
     The reverse speed ratio is established with the engagement of the torque-transmitting mechanisms  250 ,  252 , and  258 . During the reverse speed ratio, the planetary gearset  240  is rotated as a single unit along with the ring gear member  234  and the input shaft  17 . The sun gear members  232  and  222  are rotated at a speed determined by the speed of the ring gear member  234  and the ring gear/sun gear tooth ratio of the planetary gearset  230 . The planet carrier assembly member  226  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  224 , the speed of the sun gear member  222 , and the ring gear/sun gear tooth ratio of the planetary gearset  220 . The numerical value of the reverse speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  230  and  220 . 
     The first forward speed ratio is established with the engagement of the torque-transmitting mechanisms  250 ,  256 , and  258 . During the first forward speed ratio, the planetary gearset  240  rotates in unison with the ring gear member  234 . The sun gear members  222  and  232  are rotated at a speed determined by the speed of the ring gear member  224 , the speed of the planet carrier assembly member  226 , and the ring gear/sun gear tooth ratio of the planetary gearset  220 . The ring gear member  234  and planet carrier assembly member  226 , as well as output shaft  19 , are rotated at a speed determined by the speed of the sun gear member  232  and the ring gear/sun gear tooth ratio of the planetary gearset  230 . The numerical value of the first forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  220 , and  230 . 
     The second forward speed ratio is established with the engagement of the torque-transmitting mechanisms  250 ,  254 , and  258 . During the second forward speed ratio, the ring gear member  224  is connected with the input shaft  17  and the sun gear member  222  is effectively connected with the transmission housing  60  through the planetary gearsets  230  and  240 . The planet carrier assembly member  226  and, therefore, output shaft  19  are rotated at a speed determined by the speed of the ring gear member  224  and the ring gear/sun gear tooth ratio of the planetary gearset  220 . The numerical valve of the second forward speed ratio is determined by the ring gear/sun gear tooth ratio of the planetary gearset  220 . 
     The third forward speed ratio is established with the engagement of the torque-transmitting mechanisms  250 ,  254 , and  256 . During the third forward speed ratio, the planetary gearset  220  is rotated in unison with the input shaft  17  resulting in the output shaft  19  also rotating in unison with the input shaft  17 . The third forward speed ratio is a direct drive having a numerical value of one. 
     The fourth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  250 ,  252 , and  254 . During the fourth forward speed ratio, the sun gear member  242  and ring gear member  234  are rotated at a speed determined by the speed of the planet carrier assembly member  246 , the speed of the ring gear member  244 , and the ring gear/sun gear tooth ratio of the planetary gearset  240 . The sun gear members  232  and  222  are rotated at a speed determined by the speed of the ring gear member  234  and the ring gear/sun gear tooth ratio of the planetary gearset  230 . The planet carrier assembly member  226  and therefore output shaft  19  are rotated at a speed determined by the speed of the sun gear member  222 , the speed of the ring gear member  224 , and the ring gear/sun gear tooth ratio of the planetary gearset  220 . The numerical value of the fourth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  220 ,  230 , and  240 . 
     The fifth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  252 ,  254 , and  256 . During the fifth forward speed ratio, the sun gear member  242  and ring gear member  234  are rotated at a speed determined by the speed of the planet carrier assembly member  246 , the speed of the ring gear member  244 , and the ring gear/sun gear tooth ratio of the planetary gearset  240 . The sun gear member  232 , ring gear member  244 , and planet carrier assembly member  226 , as well as output shaft  19 , are rotated at a speed determined by the speed of the ring gear member  234  and the ring gear/sun gear tooth ratio of the planetary gearset  230 . The numerical value of the fifth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  230  and  240 . 
     The sixth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  250 ,  252 , and  256 . During the sixth forward speed ratio, the sun gear member  242  and ring gear member  234  are rotated at a speed determined by the speed of the planet carrier assembly member  246 , the speed of the ring gear member  244 , and the ring gear/sun gear tooth ratio of the planetary gearset  240 . The sun gear members  232  and  222  are rotated at a speed determined by the speed of the ring gear member  234  and the ring gear/sun gear tooth ratio of the planetary gearset  230 . The planet carrier assembly member  226  and therefore output shaft  19  are rotated at a speed determined by the speed of the sun gear member  222 , the speed of the ring gear member  224 , and the ring gear/sun gear tooth ratio of the planetary gearset  220 . The numerical value of the sixth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  220 ,  230 , and  240 . 
     A powertrain  310 , shown in FIG. 7, includes the engine and torque converter  12 , a planetary transmission  314 , and the final drive mechanism  16 . The planetary transmission  314  includes the input shaft  17 , a planetary gear arrangement  318 , and the output shaft  19 . The planetary gear arrangement  318  includes three planetary gearsets  320 ,  330 , and  340 , and five rotating type torque-transmitting mechanisms  350 ,  352 ,  354 ,  356 , and  358 . 
     The planetary gearset  320  includes a sun gear member  322 , a ring gear member  324 , and a planet carrier assembly member  326 . The planet carrier assembly member  326  includes a plurality of pinion gears  327  rotatably mounted on a planet carrier  329  and disposed in meshing relationship with both the sun gear member  322  and the ring gear member  324 . 
     The planetary gearset  330  includes a sun gear member  332 , a ring gear member  334 , and a planet carrier assembly member  336 . The planet carrier assembly member  336  includes a plurality of pinion gears  337  rotatably mounted on a planet carrier  339  and disposed in meshing relationship with both the sun gear member  332  and the ring gear member  334 . 
     The planetary gearset  340  includes a sun gear member  342 , a ring gear member  344 , and a planet carrier assembly member  346 . The planet carrier assembly member  346  includes a plurality of pairs of meshing pinion gears  347  and  348  that are rotatably mounted on a planet carrier  349  and disposed in meshing relationship with the sun gear member  342  and the ring gear member  344 , respectively. 
     The sun gear members  322  and  332  are continuously interconnected by an interconnecting member  370 . The ring gear member  334  and sun gear member  342  are continuously interconnected by an interconnecting member  372 . The output shaft  19  is continuously connected with the planet carrier assembly member  326 . The planet carrier assembly member  336  is continuously connected with the transmission housing  60 . 
     The input shaft  17  is selectively interconnectible with the ring gear member  324  through the torque-transmitting mechanism  350 , and selectively interconnectible with the ring gear member  344  through the torque-transmitting mechanism  352 . The planet carrier assembly member  346  is selectively connectible with the interconnecting member  370  through the torque-transmitting mechanism  354 , selectively connectible with the output shaft  19  through the torque-transmitting mechanism  356 , and selectively connectible with the ring gear member  344  through the torque-transmitting mechanism  358 . The ring gear member  324 , the planet carrier assembly member  346 , and the ring gear member  344  are noncontinuously interconnected members. 
     The truth table of FIG. 8 describes the engagement combinations and sequencing of the torque-transmitting mechanisms to establish a reverse speed ratio and six forward speed ratios between the input shaft  17  and the output shaft  19  through the planetary gear arrangement  318 . The truth table also provides an example of numerical values for the speed ratios when the ring gear/sun gear tooth ratios of the planetary gearsets  320 ,  330 , and  340  are as shown in the ratios R 1 /S 1 , R 2 /S 2 , and R 3 /S 3 , respectively. FIG. 8 also has a chart that describes the ratio steps between the adjacent forward speed ratios and between the reverse and first forward speed ratio when the example ring gear/sun gear tooth ratios are utilized. 
     The reverse speed ratio is established with the engagement of the torque-transmitting mechanisms  350 ,  352 , and  358 . During the reverse speed ratio, the planetary gearset  340  and ring gear members  324  and  334  are driven in unison with the input shaft  17 . The sun gear members  332  and  322  are rotated at a speed determined by the speed of the ring gear member  334  and the ring gear/sun gear tooth ratio of the planetary gearset  330 . The planet carrier assembly member  326  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  324 , the speed of the sun gear member  322 , and the ring gear/sun gear tooth ratio of the planetary gearset  320 . The numerical value of the reverse speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  330  and  320 . 
     The first forward speed ratio is established with the engagement of the torque-transmitting mechanisms  350 ,  356 , and  358 . During the first forward speed ratio, the sun gear members  332  and  322  are rotated at a speed determined by the speed of the ring gear member  334  and the ring gear/sun gear tooth ratio of the planetary gearset  330 . The planet carrier assembly member  326  and therefore output shaft  19  are rotated at a speed determined by the speed of the sun gear member  322 , the speed of the ring gear member  324 , and the ring gear/sun gear tooth ratio of the planetary gearset  320 . The numerical value of the first forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  320  and  330 . 
     The second forward speed ratio is established with the engagement of the torque-transmitting mechanisms  350 ,  354 , and  358 . During the second forward speed ratio, the sun gear member  322  is grounded through the combination of engagements of the torque-transmitting mechanisms  354  and  358 , and the grounded member  336  of the planetary gearset  330 . The planet carrier assembly member  326  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  324  and the ring gear/sun gear tooth ratio of the planetary gearset  320 . The numerical value of the second forward speed ratio is determined by the ring gear/sun gear tooth ratio of the planetary gearset  320 . 
     The third forward speed ratio is established with the engagement of the torque-transmitting mechanisms  350 ,  354 , and  356 . During the third forward speed ratio, the planet carrier assembly member  326  and sun gear member  322  are interconnected through the torque-transmitting mechanisms  354  and  356 . The planetary gearset  320  therefore rotates in unison with the input shaft  17 , which results in a 1:1 ratio between the input shaft  17  and the output shaft  19 . The numerical value of the third forward speed ratio is one. 
     The fourth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  350 ,  352 , and  354 . During the fourth forward speed ratio, the sun gear member  342  and ring gear member  334  are rotated at a speed determined by the speed of the ring gear member  344 , the speed of the planet carrier assembly member  346 , and the ring gear/sun gear tooth ratio of the planetary gearset  340 . The sun gear members  332  and  322  are rotated at a speed determined by the speed of the ring gear member  334  and the ring gear/sun gear tooth ratio of the planetary gearset  330 . The planet carrier assembly member  326  and therefore output shaft  19  are rotated at a speed determined by the speed of the sun gear member  322 , the speed of the ring gear member  324 , and the ring gear/sun gear tooth ratio of the planetary gearset  320 . The numerical value of the fourth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  320 ,  330 , and  340 . 
     The fifth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  352 ,  354 , and  356 . During the fifth forward speed ratio, the sun gear member  342  and ring gear member  334  are rotated at a speed determined by the speed of the ring gear member  344 , the speed of the planet carrier assembly member  346 , and the ring gear/sun gear tooth ratio of the planetary gearset  340 . The sun gear member  332 , planet carrier assembly member  346 , planet carrier assembly member  326 , and output shaft  19  are rotated at a speed determined by the speed of the ring gear member  334  and the ring gear/sun gear tooth ratio of the planetary gearset  330 . The numerical value of the fifth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  330  and  340 . 
     The sixth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  350 ,  352 , and  356 . During the sixth forward speed ratio, the ring gear member  334  and sun gear member  342  are rotated at a speed determined by the speed of the ring gear member  344 , the speed of the planet carrier assembly member  346 , and the ring gear/sun gear tooth ratio of the planetary gearset  340 . The sun gear members  332  and  322  are rotated at a speed determined by the speed of the ring gear member  334  and the ring gear/sun gear tooth ratio of the planetary gearset  330 . The planet carrier assembly member  326  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  324 , the speed of the sun gear member  322 , and the ring gear/sun gear tooth ratio of the planetary gearset  320 . The numerical value of the sixth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  320 ,  330 , and  340 . 
     A powertrain  410 , shown in FIG. 9, includes the engine and torque converter  12 , a planetary transmission  414 , and the final drive mechanism  16 . The planetary transmission  414  includes the input shaft  17 , a planetary gear arrangement  418 , and the output shaft  19 . The planetary gear arrangement  418  includes three planetary gearsets  420 ,  430 , and  440 , and five rotating type torque-transmitting mechanisms  450 ,  452 ,  454 ,  456 , and  458 . 
     The planetary gearset  420  includes a sun gear member  422 , a ring gear member  424 , and a planet carrier assembly member  426 . The planet carrier assembly member  426  includes pairs of meshing pinion gears  427  and  428  rotatably mounted on a planet carrier  429  and disposed in meshing relationship with both the sun gear member  422  and the ring gear member  424 , respectively. 
     The planetary gearset  430  includes a sun gear member  432 , a ring gear member  434 , and a planet carrier assembly member  436 . The planet carrier assembly member  436  includes a plurality of pinion gears  437  rotatably mounted on a planet carrier  439  and disposed in meshing relationship with both the sun gear member  432  and the ring gear member  434 . 
     The planetary gearset  440  includes a sun gear member  442 , a ring gear member  444 , and a planet carrier assembly member  446 . The planet carrier assembly member  446  includes a plurality of pinion gears  447  rotatably mounted on a planet carrier  449  and disposed in meshing relationship with both the sun gear member  442  and the ring gear member  444 . 
     The sun gear member  422  and ring gear member  434  are continuously interconnected by an interconnecting member  470 . The sun gear member  432  and sun gear member  442  are continuously interconnected by an interconnecting member  472 . The planet carrier assembly member  436  is continuously connected with the transmission housing  60 . The output shaft  19  is continuously connected with the planet carrier assembly member  446 . The ring gear member  424 , the planet carrier assembly member  426 , and ring gear member  444  are noncontinuously interconnected members. 
     The input shaft  17  is selectively interconnectible with the ring gear member  424  through the torque-transmitting mechanism  450 , and selectively interconnectible with the ring gear member  444  through the torque-transmitting mechanism  452 . The ring gear member  424  is selectively interconnectible with the interconnecting member  470  through the torque-transmitting mechanism  454 . The planet carrier assembly member  426  is selectively interconnectible with the interconnecting member  472  through the torque-transmitting mechanism  456 , and selectively connectible with the output shaft  19  through the torque-transmitting mechanism  458 . 
     The truth table of FIG. 10 describes the engagement combinations and sequencing for the torque-transmitting mechanisms in order to establish six forward speed ratios and one reverse speed ratio between the input shaft  17  and the output shaft  19  through the planetary gear arrangement  418 . The truth table also provides a numerical example of the speed ratios that are possible with the planetary gear arrangement  418  when the ring gear/sun gear tooth ratios of the planetary gearsets  420 ,  430 , and  440  are selected as shown in R 1 /S 1 , R 2 /S 2 , and R 3 /S 3 , respectively. Also described in FIG. 10 is a numerical example of the ratio steps between adjacent forward speed ratios and between the reverse and first forward speed ratio when the given ring gear/sun gear tooth ratios are utilized. 
     The reverse speed ratio is established with the engagement of the torque-transmitting mechanisms  450 ,  452 , and  454 . During the reverse speed ratio, the ring gear member  434  is driven by the input shaft  17 . The sun gear members  432  and  442  are rotated at a speed determined by the speed of the ring gear member  434  and the ring gear/sun gear tooth ratio of the planetary gearset  430 . The planet carrier assembly member  446  and output shaft  19  are rotated at a speed determined by the speed of the sun gear member  442 , the speed of the ring gear member  444 , and the ring gear/sun gear tooth ratio of the planetary gearset  440 . The numerical value of the reverse speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  430  and  440 . 
     The first forward speed ratio is established with the engagement of the torque-transmitting mechanisms  452 ,  454 , and  458 . During the first forward speed ratio, the sun gear members  442  and  432  are rotated at a speed determined by the speed of the ring gear member  444 , the speed of the planet carrier assembly member  446 , and the ring gear/sun gear tooth ratio of the planetary gearset  440 . The ring gear member  434 , planetary gearset  420 , and planet carrier assembly member  446 , as well as output shaft  19 , are driven at a speed determined by the speed of the sun gear member  432  and the ring gear/sun gear tooth ratio of the planetary gearset  430 . The numerical value of the first forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  430  and  440 . 
     The second forward speed ratio is established with the engagement of the torque-transmitting mechanisms  452 ,  454 , and  456 . During the second forward speed ratio, the sun gear member  442  is held stationary. The ring gear member  444  is driven by the input shaft  17 . The planet carrier assembly member  446  and output shaft  19  are rotated at a speed determined by the speed of the ring gear member  444  and the ring gear/sun gear tooth ratio of the planetary gearset  440 . The numerical value of the second forward speed ratio is determined by the ring gear/sun gear tooth ratio of the planetary gearset  440 . 
     The third forward speed ratio is established with the engagement of the torque-transmitting mechanisms  452 ,  456 , and  458 . The third forward speed ratio is a direct drive wherein the input shaft  17  and output shaft  19  are rotated in unison. Therefore, the numerical value of the third forward speed ratio is one. 
     The fourth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  450 ,  452 , and  456 . During the fourth forward speed ratio, the sun gear member  422  and ring gear member  434  are rotated at a speed determined by the speed of the ring gear member  424 , the speed of the planet carrier assembly member  426 , and the ring gear/sun gear tooth ratio of the planetary gearset  420 . The sun gear members  432  and  442  are rotated at a speed determined by the speed of the ring gear member  434  and the ring gear/sun gear tooth ratio of the planetary gearset  430 . The planet carrier assembly member  446  and output shaft  19  are rotated at a speed determined by the speed of the sun gear member  442 , the speed of the ring gear member  444 , and the ring gear/sun gear tooth ratio of the planetary gearset  440 . The numerical value of the fourth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  420 ,  430 , and  440 . 
     The fifth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  450 ,  456 , and  458 . During the fifth forward speed ratio, the planetary gearset  440  rotates as a unit with the output shaft  19 . The sun gear member  422  and ring gear member  434  are rotated at a speed determined by the speed of the ring gear member  424 , the speed of the planet carrier assembly member  426 , and the ring gear/sun gear tooth ratio of the planetary gearset  420 . The sun gear members  432  and  442 , and therefore output shaft  19 , are rotated at a speed determined by the speed of the ring gear member  434  and the ring gear/sun gear tooth ratio of the planetary gearset  430 . The numerical value of the fifth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  420  and  430 . 
     The sixth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  450 ,  452 , and  458 . During the sixth forward speed ratio, the sun gear member  422  and ring gear member  434  are rotated at a speed determined by the speed of the ring gear member  424 , the speed of the planet carrier assembly member  426 , and the ring gear/sun gear tooth ratio of the planetary gearset  420 . The sun gear members  432  and  442  are rotated at a speed determined by the speed of the ring gear member  434  and the ring gear/sun gear tooth ratio of the planetary gearset  430 . The planet carrier assembly member  446  and therefore output shaft  19  are rotated at a speed determined by the speed of the ring gear member  444 , the speed of the sun gear member  442 , and the ring gear/sun gear tooth ratio of the planetary gearset  440 . The numerical value of the sixth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  420 ,  430 , and  440 . 
     A powertrain  510 , shown in FIG. 11, includes the engine and torque converter  12 , a planetary transmission  514 , and the final drive mechanism  16 . The planetary transmission  514  includes the input shaft  17 , a planetary gear arrangement  518 , and the output shaft  19 . The planetary gear arrangement  518  includes three planetary gearsets  520 ,  530 , and  540 , and five rotating type torque-transmitting mechanisms  550 ,  552 ,  554 ,  556 , and  558 . 
     The planetary gearset  520  includes a sun gear member  522 , a ring gear member  524 , and a planet carrier assembly member  526 . The planet carrier assembly member  526  includes pairs of meshing pinion gears  527  and  528  rotatably mounted on a planet carrier  529  and disposed in meshing relationship with both the sun gear member  522  and the ring gear member  524 , respectively. 
     The planetary gearset  530  includes a sun gear member  532 , a ring gear member  534 , and a planet carrier assembly member  536 . The planet carrier assembly member  536  includes a plurality of pinion gears  537  rotatably mounted on a planet carrier  539  and disposed in meshing relationship with both the sun gear member  532  and the ring gear member  534 . 
     The planetary gearset  540  includes a sun gear member  542 , a ring gear member  544 , and a planet carrier assembly member  546 . The planet carrier assembly member  546  includes a plurality of pinion gears  547  rotatably mounted on a planet carrier  549  and disposed in meshing relationship with both the sun gear member  542  and the ring gear member  544 . 
     The sun gear member  542  and ring gear member  524  are continuously interconnected by an interconnecting member  570 . The sun gear member  532  and ring gear member  544  are continuously interconnected by an interconnecting member  572 . The planet carrier assembly member  546  is continuously connected with the transmission housing  60 . The output shaft  19  is continuously connected with the planet carrier assembly member  526 . The sun gear member  522 , the planet carrier assembly member  526 , and ring gear member  534  are noncontinuously interconnected members. 
     The input shaft  17  is selectively interconnectable with the sun gear member  522  through the torque-transmitting mechanism  550 , and selectively interconnectable with the planet carrier assembly member  536  through the torque-transmitting mechanism  552 . The planet carrier assembly member  536  is selectively interconnectable with the interconnecting member  570  through the torque-transmitting mechanism  554 . The ring gear member  534  is selectively interconnectable with the sun gear member  522  through the torque-transmitting mechanism  556 , and selectively connectible with the output shaft  19  through the torque-transmitting mechanism  558 . 
     The truth table of FIG. 12 describes the engagement combinations and sequencing for the torque-transmitting mechanisms in order to establish six forward speed ratios and one reverse speed ratio between the input shaft  17  and the output shaft  19  through the planetary gear arrangement  518 . The truth table also provides a numerical example of the speed ratios that are possible with the planetary gear arrangement  518  when the ring gear/sun gear tooth ratios of the planetary gearsets  520 ,  530 , and  540  are selected as shown in R 1 /S 1 , R 2 /S 2 , and R 3 /S 3 , respectively. Also described in FIG. 12 is a numerical example of the ratio steps between adjacent forward speed ratios and between the reverse and first forward speed ratio when the given ring gear/sun gear tooth ratios are utilized. 
     The reverse speed ratio is established with the engagement of the torque-transmitting mechanisms  550 ,  552 , and  556 . During the reverse speed ratio, the sun gear member  522  and planetary gearset  530  rotate in unison with the input shaft  17 . The sun gear member  542  is rotated at a speed determined by the speed of the ring gear member  544  and the ring gear/sun gear tooth ratio of the planetary gearset  540 . The planet carrier assembly member  526  and output shaft  19  are rotated at a speed determined by the speed of the sun gear member  522 , the speed of the ring gear member  524 , and the ring gear/sun gear tooth ratio of the planetary gearset  520 . The numerical value of the reverse speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  520  and  540 . 
     The first forward speed ratio is established with the engagement of the torque-transmitting mechanisms  550 ,  554 , and  558 . During the first forward speed ratio, the sun gear member  532  and ring gear member  544  are rotated at a speed determined by the speed of the planet carrier assembly  536 , and the ring gear/sun gear tooth ratio of the planetary gearset  540 . The ring gear member  534  and output shaft  19  are driven at a speed determined by the speed of the sun gear member  532 , the speed of the planet carrier assembly  536  and the ring gear/sun gear tooth ratio of the planetary gearset  530 . The speed of the planet carrier assembly  536  is determined by the speed of the planet carrier assembly  526 , the speed of the sun gear member  522  and the ring gear/sun gear tooth ratio of the planetary gearset  520 . The numerical value of the first forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  520 ,  530  and  540 . 
     The second forward speed ratio is established with the engagement of the torque-transmitting mechanisms  550 ,  554 , and  556 . During the second forward speed ratio, both the sun gear member  522  and ring gear member  534  are driven by the input shaft  17 . The speed of the sun gear member  532  and ring gear member  544  is determined by the speed of the planet carrier assembly member  536  and the ring gear/sun gear tooth ratio of the planetary gearset  540 . The speed of the planet carrier assembly  536  is determined by the speed of the ring gear member  534 , the speed of the sun gear member  532 , and the ring gear/sun gear tooth ratio of the planetary gearset  530 . The speed of the output shaft  19  is determined by the speed of the ring gear member  524 , the speed of the sun gear member  522 , and the ring gear/sun gear tooth ratio of the planetary gearset  520 . The numerical value of the second forward speed ratio is determined by the ring gear/sun gear tooth ratio of all three planetary gearsets  520 ,  530  and  540 . 
     The third forward speed ratio is established with the engagement of the torque-transmitting mechanisms  550 ,  556 , and  558 . The third forward speed ratio is a direct drive wherein the input shaft  17  and output shaft  19  are rotated in unison. Therefore, the numerical value of the third forward speed ratio is one. 
     The fourth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  552 ,  554 , and  556 . During the fourth forward speed ratio, the input shaft  17  drives the planet carrier assembly  536 , the sun gear member  542  and the ring gear member  524 . The speed of the sun gear member  532  and the ring gear member  544  is determined by the speed of the planet carrier assembly  536  and the ring gear/sun gear tooth ratio of the planetary gearset  540 . The ring gear member  534  and the sun gear member  522  are both rotated at a speed determined by the speed of the sun gear member  532 , the speed of the planet carrier assembly  536  and the ring gear/sun gear tooth ratio of the planetary gearset  530 . The planet carrier assembly member  526  and output shaft  19  are rotated at a speed determined by the speed of the sun gear member  522 , the speed of the ring gear member  524 , and the ring gear/sun gear tooth ratio of the planetary gearset  520 . The numerical value of the fourth forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  520 ,  530 , and  540 . 
     The fifth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  552 ,  554 , and  558 . During the fifth forward speed ratio, the planet carrier assembly  536  and the sun gear member  542  rotate at the speed of the input shaft  17 . The sun gear member  532  and ring gear member  544  are rotated at a speed determined by the speed of the planet carrier assembly  536  and the ring gear/sun gear tooth ratio of the planetary gearset  540 . The speed of the ring gear member  534 , and therefore output shaft  19 , is determined by the speed of the sun gear member  532 , the speed of the planet carrier assembly  536  and the ring gear/sun gear tooth ratio of the planetary gearset  530 . The numerical value of the fifth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  530  and  540 . 
     The sixth forward speed ratio is established with the engagement of the torque-transmitting mechanisms  552 ,  556 , and  558 . During the sixth forward speed ratio, the sun gear member  542 , the planetary gear set  520 , and therefore the output shaft  19 , rotate in unison with the ring gear member  534 . The speed of the ring gear member  544  is determined by the speed of the sun gear member  542  and the ring gear/sun gear tooth ratio of the planetary gearset  540 . The ring gear member  534  is rotated at a speed determined by the speed of the sun gear member  532 , the speed of the planet carrier assembly  536  and the ring gear/sun gear tooth ratio of the planetary gearset  530 . The numerical value of the sixth forward speed ratio is determined by the ring gear/sun gear tooth ratios of the planetary gearsets  530  and  540 . 
     The seventh forward speed ratio is established with the engagement of the torque-transmitting mechanisms  550 ,  552  and  558 . During the seventh forward speed ratio, the planet carrier assembly  536  and the sun gear member  522  are both driven by the input shaft. The ring gear member  544  and sun gear member  532  rotate at a speed determined by the speed of the sun gear member  542  and the ring gear/sun gear tooth ratio of the planetary gearset  540 . The speed of the ring gear member  534  and output shaft  19  is determined by the speed of the planet carrier assembly  536 , the speed of the sun gear member  532 , and the ring gear/sun gear tooth ratio of the planetary. gearset  530 . The ring gear member  524  rotates at a speed determined by the speed of the sun gear member  522 , the planet carrier assembly  526 , and the ring gear/sun gear tooth ratio of the planetary gearset  520 . Therefore, the seventh forward speed ratio is determined by the ring gear/sun gear tooth ratios of all three planetary gearsets  520 ,  530  and  540 . 
     From the above descriptions of the family members, it should now be apparent that each family member has a member of the first planetary gearset continuously interconnected with a member of the second planetary gearset, and the second planetary gearset has a member continuously interconnected with a member of the third planetary gearset. Also, either the first planetary gearset or second planetary gearset has a member continuously connect with the transmission housing. The transmission output shaft is continuously connected with a member of either the first or third planetary gearset. Two input clutches are utilized to interconnect the transmission input shaft with members of the first, second, or third planetary gearset. 
     Two other rotating type torque-transmitting mechanisms are employed to interconnect members of the planetary gearsets to either provide a drive connection or a lock up connection within a single planetary gearset. A fifth of the torque-transmitting mechanisms is employed to selectively interconnect members of the three planetary gearsets to the output shaft, to the housing, or to a member of one of the planetary gearsets.