CN100460717C - Multi-speed transmission and powertrain for transmitting power from a power source - Google Patents

Abstract

A multi-speed transmission for transmitting power from a power source includes a torque converter and a dual clutch which may be arranged as a dual input clutch or a dual output clutch. To combine the smoothness and ratio-enhancing effects of a torque converter with the low spin losses associated with synchronizers employed in a dual-clutch design, the torque converter and dual clutch are employed along with synchronizers and multiple meshing gears for multiple The speed ratio transmits torque from the input member to the output member.

Description

Multi-speed transmission and powertrain for transmitting power from a power source

Cross References to Related Applications

This application claims the benefit of prior US application Ser. No. 60/571,761, filed May 17, 2004, which is hereby incorporated by reference in its entirety.

technical field

The present application relates to a multi-speed dual-clutch transmission capable of being connected to a torque converter.

Background technique

Dual input clutch transmissions have been designed with friction start clutches to connect the vehicle engine with selectively engageable gears in the countershaft transmission. Dual input clutch transmissions are designed to allow engine power to be distributed through a power path with an input clutch on it engaged. Dual-input clutch power transmissions are typically designed as countershaft-type transmissions (i.e., countershaft transmissions) in which engagement of a first input clutch forms a power path from an input shaft through a first countershaft to an output shaft, a second Engagement of the input clutch creates a power path through the second countershaft to the output shaft. Synchronizers engage the gears on the layshaft to complete the flow of power to the output shaft. Countershaft designs and other transmission configurations that employ synchronizers to selectively engage gears on shafts provide relatively low rotational losses, thereby improving overall operating efficiency.

Clutches of planetary gear transmissions have been employed in the art as friction starting devices that provide starting slip in connecting a set of interconnected planetary gear sets to an input shaft that is connected to an engine to drive from The input shaft transmits power to the output shaft. One such power transmission with a friction-activated torque transfer mechanism is disclosed in commonly assigned U.S. Patent No. 6,471,616, issued October 29, 2002 to Paul D. Stevenson, which is incorporated herein by reference in its entirety .

In addition, a torque converter is also used in the art, which is connected to a planetary gear set or a countershaft gear set in a transmission to transmit power from a power source, such as an engine, to an output shaft. A torque converter adds torque between the engine and transmission to change speed. The fluid coupling of the torque converter enables smooth shifting during launch, shifting and coasting. A torque converter clutch may or may not be used to connect the engine to the transmission (bypassing the torque converter) and thereby increase the overall efficiency of the transmission. Commonly assigned U.S. Patent No. 6,729,993, issued May 4, 2004 to Norman Kenneth Bucknor et al., discloses an example of a drive train comprising an engine, a torque converter, and a transmission with three planetary gear sets that The patent literature is incorporated herein by reference in its entirety.

Contents of the invention

By utilizing a torque converter with a dual clutch transmission, the present invention combines the smoothness and ratio increasing effects of a torque converter with the low spin losses associated with synchronizing devices of a dual clutch design. For a conventional dual clutch transmission, one torque converter and two shift clutches are used instead of one damper and two launch clutches. The shift clutch can be more compact and requires less heat dissipation and cooling than the launch clutch . Therefore, it can be cheaper and lighter than a launch clutch, since the torque converter provides some of the heat sinking capacity that is required for the launch clutch. It should be noted that a damper may be employed in a torque converter, but such a damper may be smaller than would be required in an engaged friction launch clutch, since the torque converter's own inertia provides a portion of the required inertial capacity.

A powertrain with a torque converter and dual shift clutch design is particularly beneficial for vehicles with low power-to-weight ratios because the torque converter provides greater heat dissipation than conventional friction-launch clutches. Vehicles with low engine speed to vehicle ratios (i.e., low N/V, where N is engine speed in revolutions per minute (rmp) and V is mph ) in the form of vehicle speed), may be more suitable for designs having a torque converter with a double shift clutch. In addition, the relatively low spin losses of synchronizers and the large ratios that can be applied in high gears can improve fuel economy relative to other driveline designs. The use of a torque converter with a torque boost can allow the use of gear ratios with a small gradient or fewer gear ratios for the same implementation.

Thus, a multi-speed transmission is provided to transmit power from the power source. The transmission includes an input member and an output member and a torque converter operably connected between the input member and a power source to provide fluid coupling therebetween. The transmission also includes first and second shafts and a plurality of synchronizers and a plurality of meshing gears. One or more of the input member, the output member and the first and second shafts have some gears continuously connected thereto and rotate therewith. Other gears can be selectively connected and rotated with other gears through the selective engagement of the synchronizing device. Shaft and/or input or output element turns.

The transmission also includes first and second clutches alternately selectively engageable to operatively connect the first and second shafts with the input member or the output member, respectively. The first and second clutches may be referred to as dual shift clutches. When the dual shift clutch is engaged to operatively connect the first shaft and the second shaft with the input member, it refers to the dual input clutch. Similarly, when the first and second clutches are engaged to operatively connect the first and second shafts with the output member, it is referred to as a dual output clutch. As described above, the input member is operatively connected to the output member through meshing gears to transmit power from the power source to the output member by selectively engaging the clutch and synchronizing device. The power source may be a conventional internal combustion engine, but may also be a hybrid engine, a diesel engine or another form of power source.

In one aspect of the invention, the transmission includes a torque converter clutch engageable to form a mechanical connection between the power source and the input member to bypass the torque converter and operatively create a direct connection between the power source and the input member. one-to-one ratio.

A variety of different transmission configurations can employ a combination torque converter and dual shift clutch. For example, in a typical countershaft design, the first and second shafts can be spaced apart and substantially parallel to the input and output members . Alternatively, the first and second axes may be coaxial. Regardless of the countershaft or co-shaft design, alternating engagement of the first and second shift clutches is effective to connect the first and second shafts to either the input member or the output member. The operative connection of the first and second shafts to the input member or the output member by the first and second clutches may be a direct connection or an indirect connection, i.e. where the connection is through meshing gears Yes, in a particular example, meshing gears may refer to transmission gears.

The input member, output member and first and second intermediate shafts may be physically arranged with each other to form two or three or more shafts. For example, the input and output elements may be aligned with each other to form a shaft. Alternatively, the first and second shafts, input member and output member may be arranged to form three or more shafts. For example, in a dual input clutch design, the first and second shafts may be arranged as spaced countershafts and parallel to aligned input and output members, thereby forming three shafts.

The above and other features and advantages of the present invention will be further clarified in the following detailed description of the best mode for carrying out the invention with reference to the accompanying drawings.

Description of drawings

1 is a schematic diagram of a first embodiment of a vehicle having a powertrain including an engine, a torque converter, and a transmission with a dual input clutch;

2 is a schematic diagram of a second embodiment of a vehicle having a powertrain including an engine, a torque converter, and a transmission with a dual input clutch;

3 is a schematic diagram of a third embodiment of a vehicle having a powertrain including an engine, a torque converter, and a transmission with a dual input clutch;

4 is a schematic diagram of a fourth embodiment of a vehicle having a powertrain including an engine, a torque converter, and a transmission with a dual output clutch;

5 is a schematic diagram of a fifth embodiment of a vehicle having a powertrain including an engine, a torque converter, and a transmission with a dual output clutch; and

6 is a schematic diagram of a sixth embodiment of a vehicle with a powertrain including an engine, a torque converter, and a transmission with a dual input clutch.

Detailed ways

First embodiment: double input clutch, intermediate shaft designed on three shafts

Referring to the drawings, wherein like reference numerals represent like or corresponding parts throughout the several views, a vehicle 10 with a powertrain 12 is shown in FIG. 1 . Powertrain 12 includes a power source or engine 14 , a torque converter 16 and a transmission 15 . Torque converter 16 is connected to engine 14 and transmission input member 18 via turbine 22 . Selectable engagement of torque converter clutch 20 allows direct coupling of engine 14 to input shaft 18 , bypassing torque converter 16 . The input element 18 is generally a shaft, which may also be referred to herein as an input shaft. The torque converter clutch 20 is preferably electrically controlled and augmented with multiple clutch plates to provide high clutch torque capability, thereby enabling the torque converter clutch 20 to transmit high torque. The torque converter 16 includes a turbine 22 , a pump 24 and a stator 26 . The torque converter stator 26 is connected to the housing 30 through a typical one-way clutch not shown. A damper 28 is operatively connected to the engaged torque converter clutch 20 to absorb shock.

The input transfer gearset 32 includes a first transfer gear 34 , a second transfer gear 36 and a third transfer gear 38 . The third transmission gear 38 is connected with the input shaft 18 and rotates together. The first transmission gear 34 and the third transmission gear 38 mesh with each other. The first transmission gear 34 can rotate around the first intermediate shaft 40 . The first transfer gear 34 is selectively engageable with the first countershaft 40 via the first shift clutch 42 . Similarly, the second transfer gear 36 intermeshes with the third transfer gear 38 . The second transfer gear 36 is rotatable about a second intermediate shaft 44 . The second transfer gear 36 is selectively engaged with the second countershaft 44 through the second shift clutch 46. In particular, the first and second shift clutches 42 and 46 are respectively located on different shafts (that is, as shown in FIG. 1 In the embodiment, respectively, the first intermediate shaft 40 and the second intermediate shaft 44). Transmission 15 includes three main shafts and an auxiliary shaft I for idler 86 . As shown in Figure 1, the input shaft 18 and the output shaft 84 are aligned with each other to form an axis. The first and second intermediate shafts 40 and 44 lie on two separate shafts parallel to the input and output shafts 18 and 84.

Within the scope of the present invention, a shift clutch may be connected to the input shaft and engageable with the concentric first and second shafts to transmit torque from the engine to the first and second shafts, as hereinafter described in FIGS. 3 and 6 This will be described in more detail in the illustrated embodiment. However, placing the shift clutches on parallel countershafts 40 and 44 allows the clutches to be placed close to a stationary transmission housing (not shown, but substantially surrounding the transmission 15) so that a non-rotating shift piston can be used in the shift clutch. In the case of a combined torque converter and double shift clutch, other shaft configurations are possible, such as the "delta configuration " (ie a triangular structure having an input element and an output element arranged at one corner of the triangle, which together with first and second intermediate axes arranged at the other two corners form said triangular structure).

Referring again to FIG. 1 , the powertrain 12 also includes first, second, third, fourth, fifth and sixth respectively meshed gears 48 , 50 , 52 , 54 , 56 and 58 . First, third and fifth meshing gears 48 , 52 and 56 are respectively rotatable about and selectively engageable with the first countershaft 40 . Similarly, second, fourth and sixth meshing gears 50, 54 and 58 are respectively rotatable about and selectively engageable with second countershaft 44. Seventh/reverse gear 60 is also rotatable about The second countershaft 44 rotates and is selectively engageable with the second countershaft 44 .

A first synchronizer 62 is selectively engageable to connect the first meshing gear 48 with the first countershaft 40 . A second synchronizer 64 is selectively engageable to connect the second meshing gear 50 with the second countershaft 44 such that the second meshing gear 50 rotates with the second countershaft 44 . The third synchronizer 66 is selectively engageable to connect the third meshing gear 52 with the first countershaft 40 so that the third meshing gear 52 rotates with the first countershaft 40. The fourth synchronizer 68 is selectively engageable The fourth meshing gear 54 is connected with the second countershaft 44 so that the fourth meshing gear 54 rotates together with the second countershaft 44 . A fifth synchronizer 70 is selectively engageable to connect the fifth meshing gear 56 with the first countershaft 40 such that the fifth meshing gear 56 rotates with the first countershaft 40 . A sixth synchronizer 72 is selectively engageable to connect the sixth meshing gear 58 with the second countershaft 44 such that the sixth meshing gear 58 rotates with the second countershaft 44 . A seventh synchronizer 74 is selectively engageable to connect the reverse gear 60 with the second countershaft 44 so that the reverse gear 60 rotates with the second countershaft 44 .

The eighth meshing gear 76, the ninth meshing gear 78, the tenth meshing gear 80 and the eleventh meshing gear 82 are respectively continuously connected with the output element 84 and rotate together therewith. In this embodiment, the output element 84 is a shaft and may refer to the output shaft. The output shaft 84 is connected to the final drive mechanism 85. The eighth meshing gear 76 meshes with the first meshing gear 48 and the second meshing gear 50. The ninth meshing gear 78 meshes with the third meshing gear 52 and the fourth meshing gear 54. The tenth meshing gear 80 meshes with the fifth meshing gear 56 and the sixth meshing gear 58 . The idler gear 86 rotates about an axis I substantially parallel to the output shaft 84 and the second intermediate shaft 44 . The idler gear 86 intermeshes with the reverse gear 60 and the eleventh meshing gear 82 .

Transmission 15 is capable of providing six forward speed ratios and one reverse speed ratio. Within the scope of the invention, the dual clutch transmission can provide a different number of forward gear ratios, for example five or seven. By way of example, a transmission having seven forward speed ratios requires only one additional gear, which is connected to the first countershaft 40 through an additional synchronizer. The added gear will intermesh with the eleventh meshing gear 82 . Each meshing gear is designed with a specific number of teeth to create a desired torque ratio gradient between adjacent torque ratios and affect the overall attainable speed ratio within the transmission 15 . (Torque converter 16 also has a ratio-enhancing effect on the overall speed ratio).

To establish the reverse gear ratio, the seventh synchronizer 74 is engaged. Additionally, the second shift clutch 46 is engaged. With the second shift clutch 46 and the seventh synchronizer 74 engaged, torque is transferred in the opposite direction from the input shaft 18 to the output shaft 84 . Torque is transferred from input shaft 18 to second countershaft 44 via meshing second transfer gear 36 and third transfer gear 38 . Torque is transferred from second countershaft 44 via seventh meshing or reverse gear 60 , idler gear 86 and the eleventh meshing gear 82 are transmitted to the output shaft 84 . The idler gear 86 reverses the direction of rotation between the seventh/reverse gear 60 and the eleventh meshing gear 82 , thereby reversing the direction of rotation between the input shaft 18 and the output shaft 84 .

To shift from the reverse gear ratio to the first forward speed ratio, the first synchronizer 62 is preselected (ie, engaged) prior to shifting from the second shift clutch 46 to the first shift clutch 42 . Next, when the second shift clutch 46 is disengaged, the first shift clutch 42 is engaged. The seventh synchronizer then separates.

In the first forward speed ratio, torque is transferred from the input shaft 18 to the first countershaft 40 via the meshing first transfer gear 34 and third transfer gear 38 . Torque is transferred from the first countershaft 40 to the output shaft 84 via the meshing first meshing gear 48 and eighth meshing gear 76 .

To shift from the first forward speed ratio to the second forward speed ratio, the second synchronizer 64 is preselected during the first forward speed ratio. Then when the second shift clutch 46 is engaged, the first shift clutch 46 is engaged. Gear clutch 42 is disengaged. The first synchronizer 62 is then disengaged. With the second shift clutch 46 and the second synchronizer 64 engaged, torque is transferred from the input shaft 18 to the second countershaft 44 via the meshing third transfer gear 38 and the second transfer gear 36 . Torque is transferred from the second countershaft 44 to the output shaft 84 via the meshing second meshing gear 50 and the eighth meshing gear 76 to achieve the second forward speed ratio.

Since the second shift clutch 46 is not engaged during the first forward speed ratio, preselection of the second synchronizer 64 does not affect the first forward speed ratio. In transmission 15, the synchronizer required for the latter ratio is preselected during the preceding ratio. This preselection allows dynamic shifting to occur. "Dynamic shifting" means that the output torque is still present during the transition of the clutch to the next gear ratio.

To shift from the second forward speed ratio to the third forward speed ratio, the third synchronizer 66 is preselected (ie, engaged) during the second forward speed ratio. Then when the first shift clutch 42 is engaged , the second shift clutch 46 is disengaged. The second synchronizer 64 is then disengaged. With the engagement of the first shift clutch 42 and the third synchronizer 66, torque is transmitted from the input shaft 18 to the first intermediate transfer gear 34 through the meshed third transfer gear 38. shaft 40. Torque is transferred from the first countershaft 40 to the output shaft 84 via the meshing third meshing gear 52 and ninth meshing gear 78 to achieve the third forward speed ratio.

To shift from the third forward speed ratio to the fourth forward speed ratio, the fourth synchronizer 68 is preselected (ie, engaged) during the third forward speed ratio. The second shift clutch 46 is then engaged when the first shift clutch 42 is disengaged. The third synchronizer 66 is then disengaged. With the engagement of the second shift clutch 46 and the fourth synchronizer 68 , torque is transferred from the input shaft 18 to the second countershaft 44 via the engaged second transfer gear 36 and third transfer gear 38 . Torque is transferred from the second countershaft 44 to the output shaft 84 via the fourth meshing gear 54 and the ninth meshing gear 78 to achieve the fourth forward speed ratio.

To shift from the fourth forward speed ratio to the fifth forward speed ratio, the fifth synchronizer 70 is preselected (ie, engaged) during the fourth forward speed ratio. Then when the first shift clutch 42 is engaged, the second shift clutch 46 is disengaged. The fourth synchronizer 68 is then disengaged. With the first shift clutch 42 engaged, torque is transferred from the input shaft 18 via the engaged first transmission The gear 34 and the third transfer gear 33 are transmitted to the first countershaft 40 . Engaged fifth synchronizer 70 allows torque to be transferred from first countershaft 40 to output shaft 84 via fifth meshing gear 56 and tenth meshing gear 80 to achieve the fifth forward speed ratio.

To shift from the fifth forward speed ratio to the sixth forward speed ratio, the sixth synchronizer 72 is preselected (ie, engaged) during the fifth forward speed ratio. The second shift clutch 46 is then engaged when the first shift clutch 42 is disengaged. The fifth synchronizer 70 is then disengaged. With the engagement of the second shift clutch 46 and the sixth synchronizer 72 , torque is transmitted from the input shaft 18 to the second countershaft 44 via the engaged second transfer gear 36 and third transfer gear 38 , and from the second intermediate Shaft 44 is transmitted via sixth and tenth meshing gears 58 , 80 to output shaft 84 for a sixth forward speed ratio.

The eighth, ninth, ten and eleventh gears are the first set, each being continuously connected to the output shaft 84. The first transfer gear 34 and the first, third and fifth meshing gears 48, 52, 56 respectively are the second set , each of which is selectively connected to the first shaft 40 . The second transfer gear 36 and the second, fourth, sixth and seventh meshing gears 50 , 54 , 58 , 60 are a third set, each selectively connected to the second shaft 44 .

Second embodiment: double input clutch, intermediate shaft designed on three shafts, torque converter Clutch outside the torque converter

Referring to FIG. 2 , there is shown a vehicle 10' having a powertrain 12' similar to the powertrain 12 shown in FIG. 1 . The powertrain 12' differs from that shown in FIG. 1 in that the torque converter clutch 20' is moved outside of the torque converter 16'. Additionally, each component of the vehicle 10' operates in substantially the same manner as a correspondingly numbered component of the vehicle shown in FIG. 1 . As mentioned above, this rearrangement of the torque converter clutch allows room for maneuvering to allow for increased clutch plate size and/or number in the torque converter clutch and to avoid the effects of torque converter pressure on the torque converter clutch .

Third embodiment: double input clutch, coaxial shaft designed on two shafts

Referring to FIG. 3 , there is shown a vehicle 110 having a powertrain 112 including a torque converter 16 and a transmission 115 . The engine 14 and torque converter 16 are connected to an input shaft 18 in the same manner as in FIG. 1 . Dual input clutches 142 and 146 are alternately and selectively engageable to provide torque from input shaft 18 to first and second shafts 140 and 144 , respectively. The first, third and fifth meshing gears 148, 152, 156 are selectively engaged with the first shaft 140 via first, third and fifth synchronizing devices 162, 166, 170 respectively. The second, fourth and sixth The meshing gears 150, 154, 158 are respectively rotatable around the second countershaft 144, and are selectively engaged with the second countershaft 144 via the second, fourth and sixth synchronizing devices 164, 168 and 172 respectively. In addition, the seventh Or reverse gear 160 may be selectively engaged with second shaft 144 via seventh synchronizer 174. Eighth, ninth, ten, eleven, twelve, thirteen and fourteen meshing gears 176, 178, 180, 182, 175 , 177 and 179 are respectively continuously connected to an output element 184 which is connected to final drive mechanism 85 . In this embodiment, output member 184 is a shaft and may be referred to as an output shaft. Idler gear 186 is rotatable about axis I and intermeshes with seventh/reverse gear 160 and eleventh meshing gear 182 .

The eighth to fourteenth gears 175 , 176 , 177 , 178 , 179 , 180 , 182 are a first set, which are continuously connected to the output shaft 84 . The first, third and fifth gears 148, 152, 156 are a second set, each selectively connected to the first shaft 140. The second, fourth, sixth and seventh gears 150, 154, 158, 160 are a third set, Each is optionally connected to a second shaft 144.

The input shaft 18 and coaxial first and second countershafts 140, 144 form a first shaft. The output shaft 184 forms a second shaft spaced from the first shaft.

Clutches 142, 146 and synchronizers 162, 164, 166, 168, 170, 172, and 174 are selectively engageable to transmit torque from input shaft 18 through meshing gears to output shaft 184 and to establish a plurality of speed ratios, as will be appreciated by those skilled in the art This can be best understood based on the description of clutch and synchronizer engagement in FIG. 1 .

Fourth embodiment: double output clutch, coaxial shaft designed on two shafts

Referring to FIG. 4, there is shown a vehicle 210 having a powertrain 212 including a torque converter 16 and a transmission 215. The torque converter 16 is connected to the engine 14 and input in the same manner as described with reference to FIG. Between the shafts 18. The transmission 215 includes a plurality of meshing gears, some of which are continuously connected to the input shaft 18 and transmit rotation to one of the first shaft 240 or the coaxial second shaft 244 depending on the engagement of the synchronizer. Torque. The dual output clutches 242 , 246 are alternately selectively engageable with the first and second shafts 240 , 244 , respectively, to transmit torque to the output member 284 and the final drive mechanism 85 . In this embodiment, output member 284 is a shaft and may be referred to as an output shaft.

The first meshing gear 248 meshes with a twelfth meshing gear 275 , which is selectively engaged (ie, interconnected for rotation) with the first shaft 240 via the first synchronization device 262 . The third meshing gear 252 is continuously connected to the input shaft 18 and meshes with a thirteenth meshing gear 277 which is selectively meshed with the first shaft 240 via the third synchronizer 266 . The fifth meshing gear 256 is continuously connected to the input shaft 18 and meshes with the fourteenth meshing gear 279 which is selectively engaged with the first shaft 240 via the fifth synchronization device 270. The seventh meshing gear 260 is continuously connected to the input shaft 18 and meshed with the idler 286, which rotates around the idler axis 1. The idler gear 286 also meshes with an eleventh meshing gear 282 which is selectively meshable with the second shaft 244 via the seventh synchronizer 274 . The second meshing gear 250 is continuously connected to the input shaft 18 and meshes with an eighth meshing gear 276 which is selectively meshed with the second shaft 244 via the second synchronizer 264 . The fourth meshing gear 254 is continuously connected to the input shaft 18 and meshes with a ninth meshing gear 278 which is selectively meshed with the second shaft 244 via the fourth synchronizer 268 . The sixth meshing gear 258 is continuously connected to and rotates with the input shaft 18 . The sixth meshing gear 258 meshes with the tenth meshing gear 280 which is selectively meshable with the second shaft 244 via the sixth synchronization device 272 .

First, second, third, fourth, fifth, sixth and seventh gears 248 , 250 , 252 , 254 , 256 , 25 and 260 respectively belong to the first group and are continuously connected to the input shaft 18 . The twelfth, thirteenth and fourteenth gears 275 , 277 and 279 respectively belong to the second group, wherein each gear can be selectively connected to the first shaft 240 . Eighth, ninth, tenth and eleventh gears 276 , 278 , 280 and 282 belong to the third group, wherein each gear can be selectively connected to the second shaft 244 .

The input shaft 18 forms a first shaft. The coaxial first and second shafts 240, 244 and the output shaft 284 form a second shaft.

output clutches 242, 246 and synchronizers 262, 264, 266, 268, 270, 272 and 274 are selectively engageable to form six forward speed ratios and one reverse speed ratio in a manner similar to that described with reference to FIG. This is easily understood by those skilled in the art.

Fifth embodiment: double output clutch, intermediate shaft designed on three shafts

Referring to FIG. 5 , a vehicle 310 is shown having a powertrain 312 . Powertrain 312 includes engine 14, torque converter 16, transmission 315 having input shaft 18 and output member 384, and final drive 385. Torque converter 16 is connected to the engine in the same manner as previously described with reference to FIG. 14 and input shaft 18.

The eighth meshing gear 376 , the thirteenth meshing gear 377 , the ninth meshing gear 378 , the tenth meshing gear 380 and the fourteenth meshing gear 379 are continuously connected to the input shaft 18 and rotate together with the input shaft 18 . The first and second countershafts 340 , 344 are respectively spaced from and substantially parallel to the input shaft 18 . The first meshing gear 348 meshes with the eighth meshing gear 376 and is selectively connectable to the first shaft 340 via the first synchronization device 362 . The third meshing gear 352 meshes with the thirteenth meshing gear 377 and can be selectively connected to the first shaft 340 via the third synchronization device 366 . The fifth meshing gear 356 meshes with the tenth meshing gear 380 and can be selectively connected to the first shaft 340 via the fifth synchronization device 370. The idler gear 386 rotates around the idler axis I and meshes with the eighth meshing gear 376. A seventh meshing gear 360 also meshes with an idler gear 386 and is optionally connectable to the second shaft 344 via a seventh synchronizer 374 . The second meshing gear 350 meshes with the thirteenth meshing gear 377 and can be selectively connected to the second shaft 344 via the second synchronization device 364 . The fourth meshing gear 354 meshes with the ninth meshing gear 378 and is selectively connectable to the second countershaft 344 via the fourth synchronization device 368 . The sixth meshing gear 358 meshes with the fourteenth meshing gear 379 and can be selectively connected to the second shaft 344 via the sixth synchronizing device 372 . The first and second clutches 342, 346 respectively form dual output clutches and, when selectively engageable, transmit torque from the first and second shafts 340, 344, respectively. The first clutch 342 is selectively engageable to transfer torque from the first shaft 340 to a sixteenth meshing gear 383 which meshes with a seventeenth meshing gear 387 representing the final drive ring gear. The seventeenth meshing gear 387 may refer to the final drive ring gear and meshes with the output differential gear 389 to transmit torque to the output member 384 . The second clutch 346 is selectively engageable to transfer torque from the second shaft 344 to the fifth meshing gear 381 .

The eighth, ninth, tenth, thirteenth and fourteenth gears 376, 378, 380, 377 and 379 respectively belong to the first group, wherein each gear is continuously connected to the input shaft 18 and rotates with the input shaft 18 The first, third and fifth gears 348 , 352 and 356 respectively belong to the second group, wherein each gear is selectively connectable to the first shaft 340 . The second, fourth, sixth and seventh gears 350 , 354 , 358 and 360 respectively belong to the third group, wherein each gear is selectively connectable to the second shaft 344 .

The input shaft 18 forms a first shaft. The first and second shafts 340 , 344 form second and third shafts, respectively, spaced from and parallel to the input shaft 18 . The output element 384 is on the fourth axis.

Clutches 342 and 346 and synchronizers 362, 364, 366, 368, 370, 372 and 374 are selectively engageable to transmit torque between input shaft 18 and output member 384 to provide six forward speed ratios and one The reverse gear ratio is well understood by those skilled in the art based on the description of clutch and synchronizer engagement with reference to FIG. 1 .

Sixth Embodiment: Dual Input Clutch, Coaxial Shaft Formed on Three Shafts

Referring to FIG. 6 , there is shown a vehicle 410 having a powertrain 412 . The powertrain includes engine 14 and torque converter 16 connected between engine 14 and input shaft 18 in the same manner as described with reference to FIG. 1. The powertrain also includes transmission 415 having dual input clutches 442, 446 and A plurality of meshing gears and synchronizers selectively engageable to transfer torque from the input shaft 18 to the output member 484 . The first and second clutches 442, 446 are alternately engageable to transfer torque from the input shaft 18 to the first and second shafts 440, 444, respectively.

The thirteenth meshing gear 477, the twelfth meshing gear 475 and the tenth meshing gear 480 are continuously connected on the first shaft 440 and rotate together with the first shaft 440. The eighth meshing gear 476 and the ninth meshing gear 478 are continuously connected at The second shaft 444 is on and rotates with the second shaft 444 . The second meshing gear 450 meshes with the eighth meshing gear 476 and is selectively connectable to the third shaft 443 via the second synchronization device 464 . The fourth meshing gear 454 is meshed with the ninth meshing gear 478, and can be selectively connected to the third shaft 443 via the fourth synchronization device 468. The third meshing gear 452 is meshed with the thirteenth meshing gear 477, and can be Optionally connected to the third shaft 443 via the third synchronizing device 466. The first meshing gear 448 meshes with the twelfth meshing gear 475 and can be selectively connected to the third shaft 443 via the first synchronizing device 462 . The sixteenth meshing gear 483 is continuously connected to the shaft 443 and meshes with the seventeenth meshing gear 487 (final drive ring gear), which in turn meshes with the differential gear 489 for transmission to the output member 484 torque.

The sixth meshing gear 458 meshes with the ninth meshing gear 478 and is selectively connectable to the fourth shaft 445 via a sixth synchronizer 472 . Fifth meshing gear 456 meshes with tenth meshing gear 480 and is selectively connectable to fourth shaft 445 via fifth synchronizer 470. Seventh or reverse gear 460 rotates about fourth shaft 445 and is connectable via A seventh synchronizer 474 is optionally connected to the fourth shaft 445 . The first idler gear 486A is continuously connected to a shaft rotating about the axis I and meshes with the seventh meshing gear 460 when the second clutch 446 is engaged. The second idler gear 486B meshes with the twelfth meshing gear 475, and although not shown in the drawing in the two-dimensional arrangement of FIG. 486A and is capable of transmitting torque between the first shaft 440 and the fourth shaft 445 when the first clutch 442 and the seventh synchronizer 474 are engaged. The fifteenth meshing gear 481 is continuously connected to the fourth shaft 445, and although not shown in the two-dimensional schematic diagram of FIG. and output member 484 transmit torque, as will be well understood by those skilled in the art. The fifteenth meshing gear 481 , the sixteenth meshing gear 483 , the seventeenth meshing gear 487 and the differential gear 489 together form the final drive mechanism 485 .

The tenth, twelfth and thirteenth gears 480 , 475 and 477 belong to the first group respectively, wherein each gear is continuously connected to the first shaft 440 . First, second, third and fourth gears 448 , 450 , 452 and 454 respectively belong to the second group, wherein each gear can be selectively connected to the third shaft 443 . The fifth, sixth and seventh gears 456, 458 and 460 respectively belong to the third group, each of which can be selectively connected to the fourth shaft 445. The eighth and ninth meshing gears 476, 478 are continuously connected to the fourth shaft 445. On the second axis 444.

The input shaft and the coaxial first and second shafts 440, 444 form a first shaft. The third and fourth shafts 443, 445 respectively form second and third shafts spaced from and parallel to the input shaft 18. The output element 484 is located on the fourth axis.

While the best mode for carrying out the invention has been described in detail, those familiar with the art to which this invention relates will recognize other alternative designs and embodiments for carrying out the invention which fall within the scope of the appended claims Inside.

Claims (19)

1. A multi-speed transmission for transmitting power from a power source, the transmission comprising: input element; output element; a torque converter operatively connected between said input member and a power source to form a fluid coupling therebetween; first axis; second axis; It is characterized in that it also includes: seven selectively engageable synchronizers; a plurality of meshing gears, some of which are continuously connected for rotation therewith with one of said input member, output member, first shaft and second shaft; selectable engagement of a respective one of said synchronizing means to selectively interconnect the other one of said input member, output member, first and second shafts; first and second clutches alternately selectively engageable to operatively connect said respective first and second shafts with one of said input member and said output member; and The clutch selectively engages the synchronizing device, operatively connects the input member and the output member through the meshing gear, so as to convert the power source from the power source in six forward speed ratios and one reverse speed ratio. The incoming power is transmitted to the output element. 2. The multi-speed transmission of claim 1, further comprising: A torque converter clutch is operably engageable to form a mechanical connection between a power source and the output member, the mechanical connection bypassing the torque converter. 3. The multi-speed transmission of claim 1 wherein, in an intermediate shaft design, said first and second shafts are spaced apart and substantially parallel to said input member and said output member. 4. The multi-speed transmission of claim 3, wherein alternately selectable engagement of said first and second clutches respectively operatively connects said input member to said first and second shafts connected. 5. The multi-speed transmission of claim 3, wherein alternately selectable engagement of said first and second clutches respectively operatively connects said first and second shafts to said output member connected. 6. The multi-speed transmission of claim 1 wherein said first and second shafts are coaxial. 7. The multi-speed transmission of claim 6, wherein alternately selectable engagement of said first and second clutches respectively operatively connects said input member to said first and second shafts connected. 8. The multi-speed transmission of claim 6, wherein alternately selectable engagement of said first and second clutches respectively operatively connects said first and second shafts to said output member connected. 9. The multi-speed transmission of claim 1, wherein the input member, output member, first shaft and second shaft are arranged to form two shafts. 10. The multi-speed transmission of claim 1, wherein the input member, output member, first shaft and second shaft are arranged to form at least three shafts. 11. A powertrain comprising: power source; input element; a torque converter operatively connected between the power source and the input member; an output element axially offset from and collinear with said input element; first axis; second axis; It is characterized in that it also includes: fifteen meshing gears, fourteen of which are each concentric with one of said input member, output member, first shaft, and second shaft; seven synchronizers each selectively engageable to connect a respective one of said gears with one of said input member, output member, first shaft and second shaft; alternately selectively engageable first and second clutches for operatively connecting said first and second shafts with one of said input member and output member, respectively; and The clutch selectively engages the synchronizer to transmit torque from the input member to the output member through the meshing gears in six forward speed ratios and one reverse speed ratio. 12. The powertrain of claim 11, further comprising: A torque converter clutch is operably engageable to form a mechanical connection between a power source and the output member, the mechanical connection bypassing the torque converter. 13. The powertrain of claim 11 wherein, in an intermediate shaft design, said first and second shafts are spaced apart and substantially parallel to said input member and said output member. 14. The powertrain of claim 13, wherein alternately selectable engagement of said first and second clutches operably connects said input member with said first and second shafts, respectively. 15. The powertrain of claim 13, wherein alternately selectable engagement of said first and second clutches respectively operatively connect said first and second shafts with said output member. 16. The powertrain of claim 11 wherein said first and second shafts are coaxial. 17. The powertrain of claim 16, wherein alternately selectable engagement of said first and second clutches operably connects said input member with said first and second shafts, respectively. 18. The powertrain of claim 16, wherein alternately selectable engagement of said first and second clutches respectively operatively connects said first and second shafts with said output member. 19. A powertrain comprising: power source; input element; a torque converter operatively connected between the power source and the input member; output element; first axis; second axis; It is characterized in that it also includes: fifteen gears, each of said gears intermeshes with at least one other of said gears, wherein said output member has a first set of four gears of said fifteen gears continuously connected thereto for rotation therewith, A second set of four gears of the fifteen gears and a third set of five gears of the fifteen gears are selectively interconnectable with the first shaft and the second shaft, respectively, so as to accompany them One of the fifteen gears is continuously connected to and rotates with the input member, and the other of the fifteen gears is connected to one of the first set of said gears and the third set of said gears. one of the gears meshes with the idler; seven synchronizers, each of which is selectively engageable to connect one of said gears in said second or third set with one of said first and second shafts to follow rotate together; alternately selectively engageable first and second clutches for operatively connecting said first and second shafts, respectively, with said input member; and The clutch selectively engages the synchronizing device to transmit torque from the input member to the output member in various speed ratios through the meshing gears.

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