# US 11,111,965 B2 · Clutch unit for automatic transmission > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,111,965 B2 - Document ID: US11111965B2 - Status: Granted - Kind: B2 - Application number: 16/854,705 - Filed: 2020-04-21 - Published: 2021-07-08 - Granted: 2021-09-07 - Earliest claimed: 2020-01-08 - Assignees: Hyundai Motor Company; Kia Corporation - Applicants: Hyundai Motor Company; Kia Motors Corporation - Inventors: Kang Hoon Lee; Sung Hoon Park; Jae Young Jeon; Wonseok Oh - Web page: https://patentgrep.com/patent/US11111965B2 ## CPC - F16D 13/52: Clutches with multiple lamellae {; Clutches in which three or more axially moveable members are fixed alternately to the shafts to be coupled and are pressed from one side towards an axially-located member (F16D13/385 takes precedence)} - F16D 13/70: Pressure members, e.g. pressure plates, for clutch-plates or lamellae; Guiding arrangements for pressure members {(clutch flywheels comprising two or more masses with a rotational damper F16F15/12)} - F16D 3/06: specially adapted to allow axial displacement - F16D 25/0638: with more than two discs, e.g. multiple lamellae - F16D 25/082: {the line of action of the fluid-actuated members co-inciding with the axis of rotation} - F16H 57/10: Braking arrangements - F16H 63/3026: {comprising friction clutches or brakes (band brake actuating mechanisms F16H63/3003)} - F16H 57/0479: {Gears or bearings on planet carriers} - F16H 57/0484: {with variable gear ratio or for reversing rotary motion} - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - F16H: GEARING ## Abstract A clutch unit of an automatic transmission having first and second rotation elements may include a spline gear connected to the first rotation element, a clutch drum having an internal circumference spline-engaged with the spline gear to be movable in an axial direction, a clutch hub fixedly connected to a second rotation element, a plurality of clutch plates spline-engaged with the clutch drum, a plurality of clutch disks alternatingly disposed between the plurality of clutch plates and spline-engaged with the clutch hub, a supporting portion fixed to a transmission housing of the automatic transmission and configured to support the plurality of clutch plates, and a piston disposed in an interior of the transmission housing to form a hydraulic pressure chamber with the transmission housing, configured to have a rolling contact with the clutch drum interposing a bearing, and configured to transmit a pressurizing force to the plurality of clutch plates and the clutch disks through the clutch drum. ## Claims ### Claim 1 A clutch unit for an automatic transmission having a first rotation element and a second rotation element, the clutch unit comprising: a spline gear fixedly connected to the first rotation element and including spline teeth at an external circumference of the spline gear; a clutch drum having an internal circumference spline-engaged with the spline teeth of the spline gear to be movable in an axial direction of the clutch drum; a clutch hub fixedly connected to the second rotation element; a plurality of clutch plates spline-engaged with an internal circumference of the clutch drum; a plurality of clutch disks alternatingly mounted between the plurality of clutch plates and spline-engaged with an external circumference of the clutch hub; a supporting portion fixed to a transmission housing of the automatic transmission and having an end portion to support the plurality of clutch plates; and a piston mounted in an interior of the transmission housing to form a hydraulic pressure chamber with the transmission housing, configured to have a rolling contact with the clutch drum in which a first bearing is mounted between the piston and the clutch drum, and configured to transmit a pressurizing force to the plurality of clutch plates and the clutch disks through the clutch drum. ### Claim 2 (depends on 1) The clutch unit of claim 1, wherein a second bearing is mounted between the transmission housing and the spline gear. ### Claim 3 (depends on 1) The clutch unit of claim 1, wherein the clutch drum includes a pressurizing surface that pressurizes the plurality of clutch plates along the axial direction thereof. ### Claim 4 (depends on 1) The clutch unit of claim 1, further including a plurality of wave elastic members each being mounted between an adjacent pair of the plurality of clutch plates to provide a restoring force. ### Claim 5 (depends on 1) The clutch unit of claim 1, wherein a third bearing is mounted between the supporting portion and the plurality of clutch plates. ### Claim 6 (depends on 1) The clutch unit of claim 1, wherein at least one sealing member is mounted between the transmission housing and the piston so that the hydraulic pressure chamber is closed and sealed by the at least one sealing member. ### Claim 7 A clutch unit of an automatic transmission, the clutch unit comprising: a clutch drum connected to a first rotation element of the automatic transmission; a clutch hub connected to a second rotation element of the automatic transmission; a friction member set mounted between the clutch drum and the clutch hub; a piston pressurizing the friction member set by a hydraulic pressure, wherein the clutch drum is spline-engaged with a spline gear fixedly connected to the first rotation element, to be movable in an axial direction of the clutch drum, and is configured to pressurize the friction member set in the axial direction, wherein the friction member set is rolling-supported in the axial direction by a supporting portion fixed to a transmission housing of the automatic transmission, and wherein the piston mounted in an interior of the transmission housing to form a hydraulic pressure chamber with the transmission housing without relatively rotating with respect to the transmission housing has a rolling contact with the clutch drum. ### Claim 8 (depends on 7) The clutch unit of claim 7, wherein the friction member set includes: a plurality of clutch plates spline-engaged with an internal circumference of the clutch drum; and a plurality of clutch disks alternatingly mounted between the plurality of clutch plates and spline-engaged with an external circumference of the clutch hub. ### Claim 9 (depends on 8) The clutch unit of claim 8, further including a plurality of wave elastic members each being mounted between an adjacent pair of clutch plates. ### Claim 10 (depends on 8) The clutch unit of claim 8, wherein a first bearing is mounted between the supporting portion and the plurality of clutch plates. ### Claim 11 (depends on 7) The clutch of claim 7, wherein a second bearing is mounted between the transmission housing and the spline gear. ### Claim 12 (depends on 7) The clutch of claim 7, wherein a third bearing is mounted between the piston and the clutch drum. ### Claim 13 (depends on 7) The clutch unit of claim 7, wherein at least one sealing member is mounted between the transmission housing and the piston so that the hydraulic pressure chamber is closed and sealed by the at least one sealing member.