# US 11,306,631 B2 · Systems and methods for crankcase system diagnostics > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,631 B2 - Document ID: US11306631B2 - Status: Granted - Kind: B2 - Application number: 16/816,039 - Filed: 2020-03-11 - Published: 2021-09-16 - Granted: 2022-04-19 - Earliest claimed: 2020-03-11 - Assignees: Ford Global Technologies, LLC - Applicants: Ford Global Technologies, LLC - Inventors: Robert Roy Jentz; Matthew Carpenter; Michael Stephen Sweppy; Adam Joseph Krach - Web page: https://patentgrep.com/patent/US11306631B2 ## CPC - F01M 13/0011: {Breather valves} - B01D 45/08: by impingement against baffle separators - B60K 6/24: characterised by the combustion engines - B60K 6/26: characterised by the motors or the generators - B60K 6/28: characterised by the electric energy storing means, e.g. batteries or capacitors - B60Q 9/00: Arrangement or adaptation of signal devices not provided for in one of main groups B60Q1/00 - B60Q7/00 {, e.g. haptic signalling} - F01M 11/03: Mounting or connecting of lubricant purifying means relative to the machine or engine; Details of lubricant purifying means (filters B01D) - F01M 13/04: having means for purifying air before leaving crankcase, e.g. removing oil - F02M 25/06: adding lubricant vapours - F02M 35/09: Clogging indicators {; Diagnosis or testing of air cleaners (sensors therefore F02M35/10373)} - F02M 35/10222: {Exhaust gas recirculation [EGR]; Positive crankcase ventilation [PCV]; Additional air admission, lubricant or fuel vapour admission} - F02M 35/1038: {for temperature or pressure} - F01M 2013/0083: {Crankcase pressure} - F01M 2250/64: Number of revolutions - Y02T 10/12: Improving ICE efficiencies - F01M: LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - B60Q: ARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Methods and systems are provided for assessing a state of a vent hose that fluidically couples a crankcase of an engine to an engine air intake system. In one example, a method may include sealing the crankcase from the vent hose, initiating cranking of the engine, monitoring a series of pressure pulsations during a monitoring window duration via a pressure sensor positioned between a crankcase oil separator and the vent hose, and indicating a presence of degradation associated with the vent hose based on the series of pressure pulsations and the monitoring window duration. In this way, diagnosis of a state of the vent hose may be reliably assessed without crankcase pressures confounding pressure measurements as recorded via the pressure sensor. ## Claims ### Claim 1 A method comprising: sealing a crankcase of an engine from a vent hose that is part of a positive crankcase ventilation system; initiating cranking of the engine and monitoring a series of pressure pulsations during a monitoring window duration via a pressure sensor positioned between a crankcase oil separator and the vent hose; and indicating a presence or an absence of degradation based on the series of pressure pulsations and the monitoring window duration, wherein the monitoring window ends when the crankcase of the engine is no longer fully sealed from the vent hose or when the engine reaches a predetermined engine speed. ### Claim 2 (depends on 1) The method of claim 1, wherein the vent hose fluidically couples the crankcase to an air intake system of the engine. ### Claim 3 (depends on 1) The method of claim 1, wherein the pressure sensor is included on a side of the crankcase near the vent hose and the crankcase oil separator. ### Claim 4 A method comprising: sealing a crankcase of an engine from a vent hose that is part of a positive crankcase ventilation system; initiating cranking of the engine and monitoring a series of pressure pulsations during a monitoring window duration via a pressure sensor positioned between a crankcase oil separator and the vent hose; and indicating a presence or an absence of degradation based on the series of pressure pulsations and the monitoring window duration, wherein the crankcase oil separator includes one or more sealing flaps that close responsive to a pressure differential between the crankcase and the vent hose being within a predetermined threshold of a zero pressure differential; and wherein sealing the crankcase of the engine from the vent hose comprises the one or more sealing flaps closing based on the pressure differential between the crankcase and the vent hose being within the predetermined threshold of the zero pressure differential. ### Claim 5 (depends on 1) The method of claim 1, wherein the monitoring window begins when the engine cranking is initiated. ### Claim 6 (depends on 4) The method of claim 4, wherein the monitoring window ends when the crankcase of the engine is no longer fully sealed from the vent hose. ### Claim 7 (depends on 1) The method of claim 1, wherein sealing the crankcase of the engine from the vent hose includes commanding closed a valve positioned to selectively fluidically couple the crankcase to the vent hose. ### Claim 8 (depends on 1) The method of claim 1, further comprising indicating a restriction in an intake air filter of the engine responsive to the series of pressure pulsations exceeding a pressure pulsation threshold during the monitoring window duration. ### Claim 9 (depends on 8) The method of claim 8, further comprising indicating an extent of the restriction in the air intake filter as a function of another extent by which the series of pressure pulsations exceed the pressure pulsation threshold during the monitoring window duration. ### Claim 10 A system for vehicle, comprising: a crankcase of an engine including oil; an oil separator with one or more sealing flaps that selectively fluidically couple the crankcase to an air intake system of the engine by way of a vent hose that is part of a positive crankcase ventilation system; a crankcase pressure sensor positioned between the vent hose and the oil separator; and a controller with computer readable instructions stored on non-transitory memory that, when executed under conditions where the one or more sealing flaps are fully closed thereby sealing the crankcase from the vent hose, cause the controller to: via the crankcase pressure sensor, monitor an air intake system pressure profile during a monitoring window; infer a presence of degradation associated with the vent hose based on a relationship between a magnitude of the air intake system pressure profile and a duration of the monitoring window; and command mitigating action responsive to the presence of degradation. ### Claim 11 (depends on 10) The system of claim 10, further comprising a cam cover; and wherein the crankcase pressure sensor is positioned at a location between the vent hose and the oil separator. ### Claim 12 (depends on 10) The system of claim 10, wherein the controller stores further instructions to indicate that the presence of degradation includes the vent hose being disconnected from either or both of the air intake system and the crankcase; and wherein taking mitigating action includes setting a malfunction indicator light to alert an operator of the vehicle of a request to service the vehicle. ### Claim 13 (depends on 12) The system of claim 12, further comprising an onboard energy storage device that supplies power to a motor capable of propelling the vehicle; and wherein the controller stores further instructions to take mitigating action to operate the motor to propel the vehicle as frequently as possible in lieu of operation of the engine in response to the presence of degradation associated with the vent hose. ### Claim 14 (depends on 10) The system of claim 10 wherein the positive crankcase ventilation system is a dual-flow system capable of bi-directional fluid flow through the crankcase. ### Claim 15 (depends on 10) The system of claim 10, further comprising an air intake filter positioned in the air intake system upstream of a point where the vent hose is connected to the air intake system; and wherein the controller stores further instructions to indicate that the air filter is clogged in response to the air intake system pressure profile exceeding a pressure threshold during the monitoring window. ### Claim 16 (depends on 10) The system of claim 10, wherein the controller stores further instructions to initiate the monitoring window when the engine begins to rotate from a stopped position; and conclude the monitoring window when the one or more sealing flaps are no longer fully closed. ### Claim 17 A method for determining a state of a crankcase vent hose, comprising: assessing a state of the crankcase vent hose in response to a flap of an oil separator being in a closed position; not assessing the state of the crankcase vent hose in response to the flap of the oil separator being in an open position; and providing an indication of degradation in response to the assessed state of the crankcase vent hose. ### Claim 18 (depends on 17) The method of claim 17, wherein the oil separator is included in a crankcase from which stems the crankcase vent hose; and wherein the crankcase vent hose is sealed from the crankcase when the flap of the oil separator is in the closed position. ### Claim 19 (depends on 17) The method of claim 17, wherein assessing the state of the crankcase vent hose is based on a pressure profile obtained during a predetermined monitoring window, the pressure profile obtained via a crankcase pressure sensor positioned between the oil separator and the vent hose.