# US 10,871,086 B2 · Rocker arm having oil release valve that operates as an accumulator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,871,086 B2 - Document ID: US10871086B2 - Status: Granted - Kind: B2 - Application number: 16/729,679 - Filed: 2019-12-30 - Published: 2020-04-30 - Granted: 2020-12-22 - Earliest claimed: 2015-05-18 - Assignees: Eaton Corporation - Applicants: Eaton Srl - Inventors: Nicola Andrisani - Web page: https://patentgrep.com/patent/US10871086B2 ## CPC - F01L 1/18: Rocking arms or levers - F01L 1/24: by fluid means, e.g. hydraulically - F01L 9/10: by fluid means, e.g. hydraulic - F01L 13/06: for braking - F01L 13/065: {Compression release engine retarders of the "Jacobs Manufacturing" type} - F01L 2760/003: for switching to compressor action in order to brake - F01L: CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES ## Abstract An exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode can include a rocker shaft and a rocker arm. The rocker shaft can define a pressurized oil supply conduit. The rocker arm can receive the rocker shaft and is configured to rotate around the rocker shaft. The rocker arm can have an oil supply passage defined therein. A valve bridge can engage a first exhaust valve and a second exhaust valve. An accumulator assembly can be disposed in the rocker arm and includes an accumulator piston that translates within the accumulator piston housing between closed and open positions. A predetermined amount of oil is stored in the accumulator assembly. ## Claims ### Claim 1 An exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode, the exhaust valve rocker arm assembly comprising: a rocker shaft that defines a pressurized oil supply conduit; a rocker arm that receives the rocker shaft and is configured to rotate around the rocker shaft, the rocker arm having an oil supply passage and an accumulator piston housing defined therein; a valve bridge that engages a first exhaust valve and a second exhaust valve; a hydraulic lash adjuster assembly disposed on the rocker arm having a first plunger body and a second plunger body having an opening, the first plunger body movable relative to the second plunger body between a first position in the engine braking mode and a second position in the combustion mode, wherein in the first position, the first plunger body extends rigidly for cooperative engagement with the valve bridge; a check valve disposed on the rocker arm and having an actuator that selectively releases pressure in the hydraulic lash adjuster, the check valve having a check ball positioned between the first and second plunger bodies, wherein the check ball is offset from the opening permitting oil to flow through the opening during the combustion mode; and an accumulator assembly disposed in the rocker arm and including an accumulator piston that translates within the accumulator piston housing between closed and open positions, the accumulator assembly configured to store a predetermined amount of oil when the first plunger body moves toward the second position, wherein the accumulator assembly further comprises: an accumulator spring that biases the accumulator piston toward the closed position, wherein in the closed position, oil is inhibited from entering the accumulator piston housing. ### Claim 2 (depends on 1) The exhaust valve rocker assembly of claim 1 wherein in the engine braking mode, pressurized oil is communicated through the pressurized oil supply conduit, through the rocker arm oil supply passage and against the actuator such that the first plunger occupies the first position and acts on the valve bridge during rotation of the rocker arm to a first angle opening the first exhaust valve a predetermined distance while the second exhaust valve remains closed. ### Claim 3 (depends on 1) The exhaust valve rocker assembly of claim 1 wherein the hydraulic lash adjuster assembly is at least partially received by a first bore defined on the rocker arm. ### Claim 4 (depends on 1) The exhaust valve rocker assembly of claim 1 wherein the second plunger body is at least partially received by the first plunger body, wherein the second plunger body defines a valve seat. ### Claim 5 (depends on 4) The exhaust valve rocker assembly of claim 4 wherein the check valve is disposed between the first and second plunger bodies. ### Claim 6 (depends on 5) The exhaust valve rocker assembly of claim 5 wherein the check ball selectively seats against the valve seat on the second plunger body. ### Claim 7 (depends on 6) The exhaust valve rocker assembly of claim 6 wherein the actuator further comprises a needle having a longitudinal pin portion and a disk portion, wherein in the engine braking mode, pressurized oil acts against the disk portion moving the longitudinal pin portion a distance away from the check ball. ### Claim 8 (depends on 7) The exhaust valve rocker assembly of claim 7 wherein the disk portion of the actuator is received in a second bore defined in the rocker arm, wherein the first and second bores are collinear. ### Claim 9 (depends on 1) The exhaust valve rocker assembly of claim 1 wherein rotation of the rocker arm to a second predetermined angle disconnects the oil supply passage from the pressurized oil supply conduit. ### Claim 10 (depends on 1) The exhaust valve rocker assembly of claim 1, further comprising a spigot disposed on the rocker arm, wherein in the engine braking mode, subsequent to the opening of the first valve the predetermined distance, further rotation of the rocker arm causes the spigot to move the valve bridge and open the second valve while further opening the first valve. ### Claim 11 (depends on 10) The exhaust valve rocker assembly of claim 10 wherein the spigot is configured to slidably translate along a passage defined in the rocker arm prior to moving the valve bridge. ### Claim 12 An exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode, the exhaust valve rocker arm assembly comprising: a rocker shaft that defines a pressurized oil supply conduit; a rocker arm that receives the rocker shaft and is configured to rotate around the rocker shaft, the rocker arm having an oil supply passage and an accumulator piston housing defined therein; a valve bridge that engages a first exhaust valve and a second exhaust valve; a first plunger body movable between a first position and a second position, wherein in the first position, the first plunger body extends rigidly for cooperative engagement with the valve bridge; a second plunger body having an opening, the first plunger body moveable relative to the second plunger body; a check ball that seats against the opening precluding oil from flowing through the opening in the engine braking mode and that is offset from the opening permitting oil to flow through the opening in the combustion mode; an actuator that selectively releases pressure acting against the first plunger body; and an accumulator assembly disposed in the rocker arm and including an accumulator piston that translates within the accumulator piston housing between closed and open positions, the accumulator assembly configured to store a predetermined amount of oil when the first plunger body moves toward the second position, wherein the accumulator assembly further comprises: an accumulator spring that biases the accumulator piston toward the closed position. ### Claim 13 (depends on 12) The exhaust valve rocker assembly of claim 12 wherein in the engine braking mode, pressurized oil is communicated through the pressurized oil supply conduit, through the rocker arm oil supply passage and against the actuator such that the first plunger occupies the first position and acts on the valve bridge during rotation of the rocker arm to a first angle opening the first exhaust valve a predetermined distance while the second exhaust valve remains closed. ### Claim 14 (depends on 12) The exhaust valve rocker assembly of claim 12 wherein rotation of the rocker arm to a second predetermined angle disconnects the oil supply passage from the pressurized oil supply circuit. ### Claim 15 (depends on 12) The exhaust valve rocker assembly of claim 12 wherein the rocker shaft further defines a vent channel, and wherein rotation of the rocker arm to a third predetermined angle connects the oil supply passage to the vent channel releasing the oil pressure from the actuator. ### Claim 16 (depends on 12) The exhaust valve rocker assembly of claim 12, further comprising a spigot disposed on the rocker arm, wherein in the engine braking mode, subsequent to the opening of the first valve the predetermined distance, further rotation of the rocker arm causes the spigot to move the valve bridge and open the second valve while further opening the first valve. ### Claim 17 (depends on 12) The exhaust valve rocker assembly of claim 12, wherein the second plunger body is at least partially received by the first plunger body, wherein the second plunger body defines a valve seat. ### Claim 18 (depends on 17) The exhaust valve rocker assembly of claim 17 wherein a check valve is disposed between the first and second plunger bodies, the check valve further comprising the check ball that selectively seats against the valve seat on the second plunger body. ### Claim 19 (depends on 12) The exhaust valve rocker assembly of claim 12 wherein the actuator further comprises a needle having a longitudinal pin portion and a disk portion, wherein in the engine braking mode, pressurized oil acts against the disk portion moving the longitudinal pin portion a distance away from the check ball. ### Claim 20 (depends on 19) The exhaust valve rocker assembly of claim 19 wherein the disk portion of the actuator is received in a second bore defined in the rocker arm, wherein the first and second bores are collinear.