# US 8,770,156 B2 · Cold start system for a motor vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,770,156 B2 - Document ID: US8770156B2 - Status: Granted - Kind: B2 - Application number: 12/353,207 - Filed: 2009-01-13 - Published: 2010-07-15 - Granted: 2014-07-08 - Earliest claimed: 2009-01-13 - Assignees: Honda Motor Co., Ltd. - Applicants: M. Christine Theis; Reuben Bergsten - Inventors: M. Christine Theis; Reuben Bergsten - Web page: https://patentgrep.com/patent/US8770156B2 ## CPC - F02M 37/0088: {Multiple separate fuel tanks or tanks being at least partially partitioned} - F02M 37/0052: {Details on the fuel return circuit; Arrangement of pressure regulators} - F02D 41/0025: {Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures} - F02D 41/064: {at cold start (F02D41/067 takes precedence)} - Y10T 137/2534: Liquid level response - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A system and method for controlling a fuel system for a cold start of an engine is disclosed. An auxiliary fuel tank includes a separating device configured to separate a mixed fuel into a first fuel and a second fuel. A valve may be controlled to allow the flow of the first fuel to an engine of a motor vehicle to enable a cold start of the engine. ## Claims ### Claim 1 An auxiliary fuel tank for a motor vehicle, comprising: a tank body; an intake line configured to deliver a mixed fuel to the tank body; a separating device disposed within the tank body and configured to separate the mixed fuel into a first fuel and a second fuel; a first compartment formed within the tank body and configured to store the first fuel; a second compartment formed within the tank body and configured to store the second fuel, the first compartment sharing at least one wall with the second compartment and the separating device being disposed between the first compartment and the second compartment such that the separating device divides the tank body into the first compartment and the second compartment; a first fuel path configured to deliver the first fuel directly from the first compartment to an engine of the motor vehicle during a cold start; a sensor system configured to detect fuel level information of the first fuel in the first compartment; a first valve configured to control the inflow of the mixed fuel from the intake line; and wherein the first valve is controlled according to the fuel level information. ### Claim 2 (depends on 1) The auxiliary fuel tank according to claim 1, wherein the first fuel path comprises a first fuel line and a second fuel line. ### Claim 3 (depends on 2) The auxiliary fuel tank according to claim 2, further comprising a second valve connecting the first fuel line to the second fuel line and the second fuel line to a third fuel line extending from a primary fuel tank, the second valve configured to control outflow of the first fuel from the first compartment of the auxiliary fuel tank to the engine and outflow of the mixed fuel from the primary fuel tank to the engine. ### Claim 4 (depends on 3) The auxiliary fuel tank according to claim 3, wherein the second valve has a first position in which the first fuel is allowed to flow from the first compartment to the engine and the mixed fuel is blocked from flowing from the primary fuel tank to the engine and the second valve has a second position in which the mixed fuel is allowed to flow from the primary fuel tank to the engine and the first fuel is blocked from flowing from the first compartment to the engine. ### Claim 5 (depends on 1) The auxiliary fuel tank according to claim 1, wherein the sensor system comprises a low level sensor associated with a low level of the first fuel in the first compartment and wherein the sensor system comprises a high level sensor associated with a high level of the first fuel in the first compartment. ### Claim 6 (depends on 5) The auxiliary fuel tank according to claim 5, wherein the first valve is controlled to allow mixed fuel to enter the first compartment from the primary fuel tank when the low level sensor is triggered and wherein the first valve is controlled to prevent mixed fuel from entering the first compartment from the primary fuel tank when the high level sensor is triggered. ### Claim 7 A cold start system for a motor vehicle, comprising: a primary fuel tank configured to store a mixed fuel and an auxiliary fuel tank configured to receive a portion of the mixed fuel from the primary fuel tank; a separating device disposed within the auxiliary fuel tank for separating the mixed fuel into a first fuel and a second fuel; the auxiliary fuel tank including a first compartment formed within the auxiliary fuel tank and configured to store the first fuel; the auxiliary fuel tank including a second compartment formed within the auxiliary fuel tank and configured to store the second fuel, the first compartment sharing at least one wall with the second compartment and the separating device being disposed between the first compartment and the second compartment such that the separating device divides the auxiliary fuel tank into the first compartment and the second compartment; the primary fuel tank and the auxiliary fuel tank being further connected to a valve that controls flow to an engine of the motor vehicle; the valve including a first position wherein the first compartment is in fluid communication with the engine and wherein the primary fuel tank is blocked from fluid communication with the engine; the valve including a second position wherein the primary fuel tank is in fluid communication with the engine and wherein the first compartment is blocked from fluid communication with the engine; and wherein the valve is disposed in the first position whenever the engine temperature is below a predetermined temperature and wherein the valve is disposed in a second position whenever the engine temperature is above the predetermined temperature. ### Claim 8 (depends on 7) The cold start system according to claim 7, wherein the auxiliary fuel tank has a fuel path configured to deliver the first fuel directly from the first compartment to the engine. ### Claim 9 (depends on 7) The cold start system according to claim 7, wherein the separating device permits one-way fluid communication of the second fuel from the first compartment to the second compartment. ### Claim 10 (depends on 8) The cold start system according to claim 8, wherein a return line is connected to the second compartment and the primary fuel tank, wherein the return line provides fluid communication between the second compartment and the primary fuel tank, and wherein the valve is configured to block and unblock the fuel path between the auxiliary fuel tank and the engine. ### Claim 11 (depends on 10) The cold start system according to claim 10, wherein the second fuel from the second compartment is returned to the primary fuel tank using the return line. ### Claim 12 (depends on 10) The cold start system according to claim 10, wherein the fuel path includes a first fuel line and a second fuel line, the valve connecting the first fuel line to and through the second fuel line. ### Claim 13 (depends on 7) The cold start system according to claim 7, wherein the first position is associated with a cold start condition of the engine and the second position is associated with a non-cold start condition of the engine. ### Claim 14 (depends on 10) The cold start system according to claim 10, wherein a third fuel line is connected to the primary fuel tank and the valve such that fluid flows from the primary fuel tank to the second fuel line when the valve is in the second position. ### Claim 15 A method of operating a cold start system for a motor vehicle, comprising the steps of: delivering a portion of a mixed fuel from a primary fuel tank to an auxiliary fuel tank having a chamber divided into a first compartment and a second compartment by a membrane; wherein the first compartment of the auxiliary fuel tank shares at least one wall with the second compartment of the auxiliary fuel tank; using the membrane to separate the mixed fuel into a first fuel disposed in the first compartment of the auxiliary fuel tank and a second fuel disposed in the second compartment of the auxiliary fuel tank; receiving information related to a current engine temperature; comparing the current engine temperature with a predetermined engine temperature; placing the first compartment of the auxiliary fuel tank in fluid communication with an engine and blocking fluid communication between the primary fuel tank and the engine whenever the current engine temperature is less than the predetermined engine temperature; and placing the primary fuel tank in fluid communication with the engine and blocking fluid communication between the auxiliary fuel tank and the engine whenever the current engine temperature is above the predetermined engine temperature. ### Claim 16 (depends on 15) The method according to claim 15, wherein the step of placing the first compartment of the auxiliary fuel tank in fluid communication with the engine includes delivering the first fuel directly from the first compartment of the auxiliary fuel tank to the engine. ### Claim 17 (depends on 16) The method according to claim 16, wherein the step of placing the first compartment of the auxiliary fuel tank in fluid communication with the engine includes moving a valve to a first position from a second position. ### Claim 18 (depends on 15) The method according to claim 15, wherein the step of receiving information related to a current engine temperature includes a step of receiving information related to a current fuel level of the auxiliary fuel tank. ### Claim 19 (depends on 18) The method according to claim 18, wherein the step of receiving information related to the current fuel level is followed by a step of placing the auxiliary fuel tank in fluid communication with the primary fuel tank and thereby allowing mixed fuel to flow from the primary fuel tank to the auxiliary fuel tank whenever the current fuel level is low. ### Claim 20 (depends on 17) The method according to claim 17, wherein the step of placing the primary fuel tank in fluid communication with the engine includes moving the valve from the first position to the second position. ### Claim 21 A cold start system for a motor vehicle, comprising: a primary fuel tank configured to store a mixed fuel and an auxiliary fuel tank disposed within the primary fuel tank, the auxiliary fuel tank configured to receive a portion of the mixed fuel from the primary fuel tank; a membrane for separating the mixed fuel into a first fuel and a second fuel, the membrane being disposed between the auxiliary fuel tank and the primary fuel tank such that the membrane forms a boundary between the auxiliary fuel tank and the primary fuel tank; the membrane allowing the second fuel to pass from the auxiliary fuel tank to the primary fuel tank and the membrane preventing the mixed fuel from passing from the primary fuel tank to the auxiliary fuel tank; a first fuel path configured to deliver the first fuel directly from the auxiliary fuel tank to an engine; and wherein the primary fuel tank is in fluid communication with the engine when the engine temperature is above a predetermined engine temperature and wherein the auxiliary fuel tank is in fluid communication with the engine when the engine temperature is below a predetermined engine temperature.