# US 11,306,628 B2 · Continuous variable valve duration apparatus and engine provided with the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,628 B2 - Document ID: US11306628B2 - Status: Granted - Kind: B2 - Application number: 17/113,012 - Filed: 2020-12-05 - Published: 2021-12-09 - Granted: 2022-04-19 - Earliest claimed: 2020-06-09 - Assignees: Hyundai Motor Company; Kia Motors Corporation - Applicants: Hyundai Motor Company; Kia Motors Corporation - Inventors: Hyeon Woo Kim; Kyoung Pyo Ha; Back Sik Kim; Jong Gu Kim - Web page: https://patentgrep.com/patent/US11306628B2 ## CPC - F01L 13/0063: {by modification of cam contact point by displacing an intermediate lever or wedge-shaped intermediate element, e.g. Tourtelot} - F01L 1/047: Camshafts - F01L 1/0532: {the cams being directly in contact with the driven valve} - F01L 1/356: making the angular relationship oscillate {, e.g. non-homokinetic drive} - F01L 13/0015: {for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque} - F01L 2001/0473: {Composite camshafts, e.g. with cams or cam sleeve being able to move relative to the inner camshaft or a cam adjusting rod} - F01L 2001/0475: {Hollow camshafts} - F01L 2001/0476: {Camshaft bearings} - F01L 2301/00: Using particular materials - F01L 2810/03: Reducing vibration - F01L 2810/04: Reducing noise - F01L 2820/032: Electric motors - F01L: CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES ## Abstract A continuously variable valve duration apparatus includes a camshaft, a cam unit on which a cam is formed, a guide bracket including an upper guide boss, an internal wheel configured to transmit rotation of the camshaft to the cam unit, a wheel housing in which the internal wheel is rotatably inserted, wherein a guide thread is formed in a portion of the wheel housing, and of which a guide shaft is formed to be movably inserted into the upper guide boss, a worm wheel to which an internal thread engaging with the guide thread is formed in the worm wheel, and to which an external thread is formed thereon, a control shaft on which a control worm engaged with the external thread is formed, and an upper bushing mounted on a lower portion of the upper guide boss to support the guide shaft. ## Claims ### Claim 1 A valve duration control apparatus comprising: a camshaft; a cam unit on which a cam is formed, wherein the camshaft is inserted into the cam unit; a guide bracket including an upper guide boss; an internal wheel configured to transmit a rotation of the camshaft to the cam unit; a wheel housing in which the internal wheel is rotatably inserted, wherein a guide thread is formed in a portion of the wheel housing, and wherein the wheel housing includes a guide shaft movably inserted into the upper guide boss; a worm wheel to which an internal thread engaging with the guide thread is formed in the worm wheel, wherein an external thread is formed on the worm wheel; a control shaft including a control worm engaged with the external thread; and an upper bushing mounted on a lower portion of the upper guide boss to support the guide shaft. ### Claim 2 (depends on 1) The valve duration control apparatus of claim 1, wherein the guide bracket further includes a lower guide boss, and wherein the wheel housing includes a guide rod inserted into the lower guide boss to guide a movement of the wheel housing. ### Claim 3 (depends on 2) The valve duration control apparatus of claim 2, further including a lower bushing mounted on a lower portion of the lower guide boss to support the guide rod. ### Claim 4 (depends on 2) The valve duration control apparatus of claim 2, wherein a center portion of the internal wheel is aligned to deviate from an imaginary line connecting the upper guide boss and the lower guide boss. ### Claim 5 (depends on 1) The valve duration control apparatus of claim 1, further including an insert mounted between the wheel housing and the guide bracket. ### Claim 6 (depends on 5) The valve duration control apparatus of claim 5, wherein the insert is fixed to one of the wheel housing and the guide bracket. ### Claim 7 (depends on 5) The valve duration control apparatus of claim 5, wherein the insert is made of plastic material. ### Claim 8 (depends on 5) The valve duration control apparatus of claim 5, wherein a cross-section of the insert is formed in a “U” shape. ### Claim 9 (depends on 1) The valve duration control apparatus of claim 1, wherein a control shaft hole that supports the control shaft is formed at the guide bracket. ### Claim 10 (depends on 9) The valve duration control apparatus of claim 9, further including a control shaft bearing mounted on the control shaft hole to support rotatably the control shaft. ### Claim 11 (depends on 1) The valve duration control apparatus of claim 1, further including a thrust bearing mounted on the upper guide boss to support the worm wheel. ### Claim 12 (depends on 1) The valve duration control apparatus of claim 1, further including a stepped surface formed at the guide bracket to prevent a rotation of the wheel housing. ### Claim 13 (depends on 1) The valve duration control apparatus of claim 1, further including: a first sliding hole and a second sliding hole respectively formed at the internal wheel; a cam slot formed at the cam unit; a roller wheel connected to the camshaft and rotatably inserted into the first sliding hole; and a roller cam slidably inserted into the cam slot and rotatably inserted into the second sliding hole. ### Claim 14 (depends on 13) The valve duration control apparatus of claim 13, wherein the roller cam includes: a roller cam body slidably inserted into the cam slot; a cam head rotatably inserted into the second sliding hole; and a protrusion formed in a longitudinal direction of the camshaft and configured to inhibit the roller cam from being removed from the internal wheel. ### Claim 15 (depends on 14) The valve duration control apparatus of claim 14, wherein the roller wheel includes: a wheel body slidably connected to the camshaft; and a wheel head rotatably inserted into the first sliding hole. ### Claim 16 (depends on 15) The valve duration control apparatus of claim 15, further including: a camshaft oil hole formed within the camshaft in a longitudinal direction of the camshaft; a body oil hole formed at the wheel body of the roller wheel and fluidically-communicating with the camshaft oil hole; and an oil groove formed at the wheel head of the roller wheel and fluidically-communicating with the body oil hole. ### Claim 17 (depends on 1) The valve duration control apparatus of claim 1, wherein the cam unit includes a first cam portion and a second cam portion which are mounted corresponding to a cylinder and an adjacent cylinder respectively, and wherein the internal wheel includes a first internal wheel and a second internal wheel of transmitting the rotation of the camshaft to the first cam portion and the second cam portion, respectively. ### Claim 18 (depends on 17) The valve duration control apparatus of claim 17, wherein the first internal wheel and the second internal wheel are rotatably connected to each other. ### Claim 19 (depends on 17) The valve duration control apparatus of claim 17, further including first and second bearings internally mounted within the wheel housing and supporting the first internal wheel and the second internal wheel respectively. ### Claim 20 (depends on 1) An engine mounted with including the valve duration control apparatus of claim 1.