# US 2018/0023670 A1 · Dual clutch transmission for a motor vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0023670 A1 - Document ID: US20180023670A1 - Status: Published application - Kind: A1 - Application number: 15/551,756 - Filed: 2016-01-20 - Published: 2018-01-25 - Earliest claimed: 2015-02-19 - Assignees: Audi AG - Applicants: Audi AG - Inventors: Steffen HUMMEL - Web page: https://patentgrep.com/patent/US20180023670A1 ## CPC - F16H 3/006: {power being selectively transmitted by parallel flow paths, e.g. dual clutch transmissions} - F16H 3/089: all of the meshing gears being supported by a pair of parallel shafts, one being the input shaft and the other the output shaft, there being no countershaft involved - F16H 2003/0803: {with countershafts coaxial with input or output shaft} - F16H 2003/0818: {comprising means for power-shifting} - F16H 2003/0822: {characterised by the arrangement of at least one reverse gear} - F16H 2003/0826: {wherein at least one gear on the input shaft, or on a countershaft is used for two different forward gear ratios} - F16H 2200/0078: the gear ratio comprising twelve or more forward speeds - F16H: GEARING ## Abstract A dual-clutch transmission for a motor vehicle, with gear wheel sets engageable via shift elements, with the gear wheel sets forming particularly precisely eight wheel planes, each of which is allocated to a first sub-transmission and a second sub-transmission, of which each sub-transmission has an input shaft and both sub-transmissions have a common output shaft. The input shafts, which are coaxial with respect to one another, can each be activated in an alternating manner via a power-shift clutch, and the even forward gears are allocated to the first sub-transmission and the odd forward gears are allocated to the second sub-transmission, which can be engaged upon a gear change by way of the shift elements. ## Claims ### Claim at position 1 1-17. (canceled) ### Claim 18 A dual-clutch transmission for a motor vehicle, comprising: with gear wheel sets engageable via first to seventh shift elements, with the gear wheel sets forming precisely eight first to eighth wheel planes in series in the axial direction from the input side to the output side of the dual-clutch transmission, each wheel plane being allocated to a first sub-transmission and to a second sub-transmission, of which the first sub-transmission has an input shaft and the second sub-transmission has a second input shaft and both sub-transmissions have a common output shaft, wherein the input shafts, which are coaxial with respect to one another, can each be activated in an alternating manner via a power-shift clutch, and the even forward gears are allocated to the first sub-transmission and the odd forward gears are allocated to the second sub-transmission, which can be engaged upon a gear shift by way of the first to seventh shift elements, wherein each wheel plane provides a direct gear as a forward gear, with which, when the first or second sub-transmission is activated, precisely one wheel plane is engaged in the torque flow extending through the activated first or second sub-transmission, and wherein the wheel planes additionally provide at least one torsion gear as a forward gear, in which precisely three wheel planes, which are combined in series, are engaged in the torque flow by the first to seventh shift elements, wherein a total of four torsion forward gears, with a total of eight wheel planes, can be provided, and in that three wheel planes engaged for each torsion gear are allocated either completely to the first sub-transmission or completely to the second sub-transmission, so that, with each engaged torsion forward gear, only the sub-transmission having three wheel planes engaged for the respective torsion gear is integrated into the torque flow, and the other sub-transmission is completely de-coupled from the torque flow. ### Claim 19 (depends on 18) The dual-clutch transmission according to claim 18, wherein precisely five shift elements, engageable on both sides in the axial direction, are provided for engaging the forward gears, and two shift elements are provided, which can be engaged on one side in the axial direction. ### Claim 20 (depends on 19) The dual-clutch transmission according to claim 19, wherein, of the five shift elements, which can be engaged on both sides, precisely four shift elements are arranged coaxially with respect to the input axis of the first and second input shafts, and precisely one shift element, which can be engaged on both sides, is arranged on the output shaft. ### Claim 21 (depends on 18) The dual-clutch transmission according to claim 18, wherein at least two of the shift elements can be actuated in order to engage all of the forward gears. ### Claim 22 (depends on 18) The dual-clutch transmission according to claim 18, wherein the first and second input shafts of the eight wheel planes are free of torsion-resistant gear wheels arranged thereupon, and in that the first input shaft has precisely one first shift element, which can be engaged on both sides in the axial direction, and the second input shaft has precisely one second shift element, which can be engaged on both sides in the axial direction, and in that the first input shaft can be linked to the first to fourth wheel planes of the first sub-transmission, or can be de-coupled therefrom, by means of the first shift element, and in that the second input shaft can be linked to the fifth to eighth wheel planes of the second sub-transmission, or can be de-coupled therefrom, by means of the second shift element. ### Claim 23 (depends on 22) The dual-clutch transmission according to claim 22, wherein a drive-side detached gear wheel of a first wheel plane, mounted on the first input shaft, and a drive-side hollow shaft of the first sub-transmission, coaxially mounted on the first input shaft is arranged on both sides of the first shift element in the axial direction, which can be coupled in an alternating manner to the first input shaft via the first shift element, and the drive-side hollow shaft of the first sub-transmission supports a fixed gear wheel of the second wheel plane and a fixed gear wheel of the third wheel plane. ### Claim 24 (depends on 23) The dual-clutch transmission according to claim 23, wherein a drive-side gear wheel of the fourth wheel plane is detachably mounted on the drive-side hollow shaft of the first sub-transmission, and the drive-side hollow shaft of the first sub-transmission can be linked to the detachably mounted drive-side gear wheel of the fourth wheel plane by way of a third shift element. ### Claim 25 (depends on 24) The dual-clutch transmission according to claim 24, wherein the fifth wheel plane, directly adjacent to the first sub-transmission in the axial direction, is allocated to the second sub-transmission, and in that the fifth wheel plane can be linked to the first sub-transmission by the third shift element. ### Claim 26 (depends on 25) The dual-clutch transmission according to claim 25, wherein the fifth wheel plane, which can be engaged on both sub-transmissions, is detachably mounted with its drive-side gear wheel on the second input shaft, and the drive-side gear wheel of the fifth wheel plane can be linked to the drive-side hollow shaft of the first sub-transmission by means of the third shift element. ### Claim 27 (depends on 22) The dual-clutch transmission according to one of claim 22, wherein a drive-side detached gear wheel of the eighth wheel plane which is mounted on the second input shaft, and a drive-side hollow shaft, which is coaxially mounted on the second input shaft is arranged on both sides of the second shift element of the second sub-transmission in the axial direction, and the detached gear wheel of the eighth wheel plane and the drive-side hollow shaft of the second sub-transmission can be linked, in an alternating manner, to the second input shaft via the second shift element, and the drive-side hollow shaft of the second sub-transmission supports at least one fixed gear wheel of the seventh wheel plane. ### Claim 28 (depends on 27) The dual-clutch transmission according to claim 27, wherein a drive-side gear wheel of the sixth wheel plane is detachably mounted on the drive-side hollow shaft of the second sub-transmission, and the drive-side hollow shaft of the second sub-transmission has a fourth shift element, with which the detachably mounted drive-side gear wheel of the sixth wheel plane can be linked to the drive-side hollow shaft of the second sub-transmission. ### Claim 29 (depends on 28) The dual-clutch transmission according to claim 28, wherein the drive-side gear wheel of the fifth wheel plane engageable on both sub-transmissions can be linked to the second sub-transmission by the fourth shift element. ### Claim 30 (depends on 18) The dual-clutch transmission according to claim 18, wherein the output-side gear wheels of the first and second wheel planes of the first sub-transmission are arranged, in a torsionally resistant manner, on an output-side hollow shaft of the first sub-transmission, which is rotatably mounted coaxially on the output shaft. ### Claim 31 (depends on 30) The dual-clutch transmission according to claim 30, wherein the output shaft has a fifth shift element, by means of which the output-side hollow shaft of the first sub-transmission or an output-side gear wheel of the third wheel plane can be linked in an alternating manner to the output shaft in the first sub-transmission. ### Claim 32 (depends on 18) The dual-clutch transmission according to claim 18, wherein the output-side gear wheels of the seventh and eighth wheel planes of the second sub-transmission are arranged, in a torsionally resistant manner, on an output-side hollow shaft of the second sub-transmission, which is rotatably mounted coaxially on the output shaft. ### Claim 33 (depends on 32) The dual-clutch transmission according to claim 32, wherein the output shaft has a sixth shift element, by means of which the output-side hollow shaft of the second sub-transmission can be linked to the output shaft. ### Claim 34 (depends on 26) The dual-clutch transmission according to claim 26, wherein the output-side gear wheel of the fifth wheel plane, which can be engaged on both sub-transmissions, is detachably mounted on the output shaft and can be linked to the output shaft by way of a seventh shift element.