# US 9,752,660 B2 · Planetary gear train of automatic transmission for a vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,752,660 B2 - Document ID: US9752660B2 - Status: Granted - Kind: B2 - Application number: 14/947,281 - Filed: 2015-11-20 - Published: 2017-03-16 - Granted: 2017-09-05 - Earliest claimed: 2015-09-14 - Assignees: Hyundai Motor Company - Applicants: Hyundai Motor Company - Inventors: Hyun Sik Kwon; Jae Chang Kook; Seongwook Ji; Wonmin Cho; Wookjin Jang; Seong Wook Hwang - Web page: https://patentgrep.com/patent/US9752660B2 ## CPC - F16H 3/66: composed of a number of gear trains without drive passing from one train to another - F16H 2003/445: {without permanent connection between the input and the set of orbital gears} - F16H 2200/006: the gear ratios comprising eight forward speeds - F16H 2200/201: with three sets of orbital gears - F16H 2200/2046: with six engaging means - F16H 2200/2097: comprising an orbital gear set member permanently connected to the housing, e.g. a sun wheel permanently connected to the housing - F16H: GEARING ## Abstract A planetary gear train of an automatic transmission for a vehicle may include an input shaft receiving torque of an engine, an output shaft, a first planetary gear set, a second planetary gear set, a third planetary gear set, six friction elements disposed to selectively connect rotation elements of the planetary gear sets with each other and selectively connect the rotation elements with a transmission housing, a first rotation shaft selectively connected to the input shaft, a second rotation shaft, a third rotation shaft selectively connected to at least one of the input shaft and the transmission housing, a fourth rotation shaft selectively connected to the second rotation shaft, a fifth rotation shaft selectively connected to the second rotation shaft, a sixth rotation shaft directly connected to the transmission housing, and a seventh rotation shaft selectively connected to the second rotation shaft, and directly connected to the output shaft. ## Claims ### Claim 1 A planetary gear train of an automatic transmission for a vehicle, comprising: an input shaft receiving torque of an engine; an output shaft outputting changed torque of the engine; a first planetary gear set including first, second, and third rotation elements; a second planetary gear set including fourth, fifth, and sixth rotation elements; a third planetary gear set including seventh, eighth, and ninth rotation elements; six friction elements disposed to selectively connect the rotation elements with each other and selectively connect the rotation elements with a transmission housing; a first rotation shaft including the first and ninth rotation elements and selectively connected to the input shaft; a second rotation shaft including the second rotation element; a third rotation shaft including the third rotation element and selectively connected to at least one of the input shaft and the transmission housing; a fourth rotation shaft including the fourth rotation element and selectively connected to the second rotation shaft; a fifth rotation shaft including the fifth and seventh rotation elements and selectively connected to the second rotation shaft; a sixth rotation shaft including the sixth rotation element and directly connected to the transmission housing; and a seventh rotation shaft including the eighth rotation element and selectively connected to the second rotation shaft, and directly connected to the output shaft. ### Claim 2 (depends on 1) The planetary gear train of claim 1, wherein: the first planetary gear set is a single-pinion planetary gear set, in which the first rotation element is a first sun gear, the second rotation element is a first planet carrier, and the third rotation element is a first ring gear, the second planetary gear set is a single-pinion planetary gear set, in which the fourth rotation element is a second sun gear, the fifth rotation element is a second planet carrier, and the sixth rotation element is a second ring gear, and the third planetary gear set is a single-pinion planetary gear set, in which the seventh rotation element is a third sun gear, the eighth rotation element is a third planet carrier, and the ninth rotation element is a third ring gear. ### Claim 3 (depends on 1) The planetary gear train of claim 1, wherein the six friction elements comprise: a first clutch selectively connecting the input shaft and the first rotation shaft; a second clutch selectively connecting the input shaft and third rotation shaft; a third clutch selectively connecting the second rotation shaft and the seventh rotation shaft; a fourth clutch selectively connecting the second rotation shaft and the fourth rotation shaft; a fifth clutch selectively connecting the second rotation shaft and the fifth rotation shaft; and a first brake selectively connecting the third rotation shaft and the transmission housing. ### Claim 4 (depends on 3) The planetary gear train of claim 3, wherein shift speed stages achieved by selectively operating the six friction elements comprise: a first forward speed stage achieved by simultaneous operation of the first and fifth clutches and the first brake; a second forward speed stage achieved by simultaneous operation of the first and fourth clutches and the first brake; a third forward speed stage achieved by simultaneous operation of the first, fourth, and fifth clutches; a fourth forward speed stage achieved by simultaneous operation of the first, third, and fourth clutches; a fifth forward speed stage achieved by simultaneous operation of the first, second, and fourth clutches; a sixth forward speed stage achieved by simultaneous operation of the second, third, and fourth clutches; a seventh forward speed stage achieved by simultaneous operation of the second, third, and fifth clutches; an eighth forward speed stage achieved by simultaneous operation of the second, fourth, and fifth clutches; and a reverse speed stage achieved by simultaneous operation of the first and third clutches, and the first brake. ### Claim 5 A planetary gear train of an automatic transmission for a vehicle, comprising: an input shaft receiving torque of an engine; an output shaft outputting changed torque; a first planetary gear set being a single-pinion planetary gear set, and including first, second, and third rotation elements; a second planetary gear set being a single-pinion planetary gear set, and including fourth, fifth and sixth rotation elements; and a third planetary gear set being a single-pinion planetary gear set, and including seventh, eighth and ninth rotation elements; a first rotation shaft including the first and ninth rotation elements and selectively connected to the input shaft; a second rotation shaft including the second rotation element; a third rotation shaft including the third rotation element and selectively connected to the input shaft or the transmission housing; a fourth rotation shaft including the fourth rotation element and selectively connected to the second rotation shaft; a fifth rotation shaft including the fifth and seventh rotation elements and selectively connected to the second rotation shaft; a sixth rotation shaft including the sixth rotation element and directly connected to the transmission housing; a seventh rotation shaft including the eighth rotation element and selectively connected to the second rotation shaft, and directly connected to the output shaft; a first clutch selectively connecting the input shaft and the first rotation shaft; a second clutch selectively connecting the input shaft and third rotation shaft; a third clutch selectively connecting the second rotation shaft and the seventh rotation shaft; a fourth clutch selectively connecting the second rotation shaft and the fourth rotation shaft; a fifth clutch selectively connecting the second rotation shaft and the fifth rotation shaft; and a first brake selectively connecting the third rotation shaft and the transmission housing. ### Claim 6 (depends on 5) The planetary gear train of claim 5, wherein: the first planetary gear set is a single-pinion planetary gear set, in which the first rotation element is a first sun gear, the second rotation element is a first planet carrier, and the third rotation element is a first ring gear, the second planetary gear set is a single-pinion planetary gear set, in which the fourth rotation element is a second sun gear, the fifth rotation element is a second planet carrier, and the sixth rotation element is a second ring gear, and the third planetary gear set is a single-pinion planetary gear set, in which the seventh rotation element is a third sun gear, the eighth rotation element is a third planet carrier, and the ninth rotation element is a third ring gear. ### Claim 7 (depends on 5) The planetary gear train of claim 5, wherein shift speed stages achieved by selectively operating the five clutches and the one brake comprise: a first forward speed stage achieved by simultaneous operation of the first and fifth clutches and the first brake; a second forward speed stage achieved by simultaneous operation of the first and fourth clutches and the first brake; a third forward speed stage achieved by simultaneous operation of the first, fourth, and fifth clutches; a fourth forward speed stage achieved by simultaneous operation of the first, third, and fourth clutches; a fifth forward speed stage achieved by simultaneous operation of the first, second, and fourth clutches; a sixth forward speed stage achieved by simultaneous operation of the second, third, and fourth clutches; a seventh forward speed stage achieved by simultaneous operation of the second, third, and fifth clutches; an eighth forward speed stage achieved by simultaneous operation of the second, fourth, and fifth clutches; and a reverse speed stage achieved by simultaneous operation of the first and third clutches, and the first brake. ### Claim 8 A planetary gear train of an automatic transmission for a vehicle, comprising: an input shaft receiving torque of an engine; an output shaft outputting changed torque; a first planetary gear set being a single-pinion planetary gear set, and including first sun gear, a first ring gear, and a first planet carrier as rotation elements; a second planetary gear set being a single-pinion planetary gear set, and including a second sun gear, a second ring gear and a second planet carrier as rotation elements; and a third planetary gear set being a single-pinion planetary gear set, and including a third sun gear, a third ring gear and a third planet carrier as rotation elements; a first rotation shaft including the first sun gear and the third ring gear and selectively connected to the input shaft; a second rotation shaft including the first planet carrier; a third rotation shaft including the first ring gear and selectively connected to the input shaft or a transmission housing; a fourth rotation shaft including the second sun gear and selectively connected to the second rotation shaft; a fifth rotation shaft including the second planet carrier and the third sun gear and selectively connected to the second rotation shaft; a sixth rotation shaft including the second ring gear and directly connected to the transmission housing; a seventh rotation shaft including the third planet carrier and selectively connected to the second rotation shaft and directly connected to the output shaft; and six friction elements disposed to selectively connect the rotation elements with each other and selectively connect the rotation elements with a transmission housing. ### Claim 9 (depends on 8) The planetary gear train of claim 8, wherein the six friction elements comprise: a first clutch selectively connecting the input shaft and the first rotation shaft; a second clutch selectively connecting the input shaft and third rotation shaft; a third clutch selectively connecting the second rotation shaft and the seventh rotation shaft; a fourth clutch selectively connecting the second rotation shaft and the fourth rotation shaft; a fifth clutch selectively connecting the second rotation shaft and the fifth rotation shaft; and a first brake selectively connecting the third rotation shaft and the transmission housing. ### Claim 10 (depends on 9) The planetary gear train of claim 9, wherein shift speed stages achieved by selectively operating the six friction elements comprise: a first forward speed stage achieved by simultaneous operation of the first and fifth clutches and the first brake; a second forward speed stage achieved by simultaneous operation of the first and fourth clutches and the first brake; a third forward speed stage achieved by simultaneous operation of the first, fourth, and fifth clutches; a fourth forward speed stage achieved by simultaneous operation of the first, third, and fourth clutches; a fifth forward speed stage achieved by simultaneous operation of the first, second, and fourth clutches; a sixth forward speed stage achieved by simultaneous operation of the second, third, and fourth clutches; a seventh forward speed stage achieved by simultaneous operation of the second, third, and fifth clutches; an eighth forward speed stage achieved by simultaneous operation of the second, fourth, and fifth clutches; and a reverse speed stage achieved by simultaneous operation of the first and third clutches and the first brake.