US20100147847A1 - Method of controlling operational venting of a plastics fuel tank and plastics fuel tank - Google Patents

Method of controlling operational venting of a plastics fuel tank and plastics fuel tank Download PDF

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Publication number
US20100147847A1
US20100147847A1 US12/639,378 US63937809A US2010147847A1 US 20100147847 A1 US20100147847 A1 US 20100147847A1 US 63937809 A US63937809 A US 63937809A US 2010147847 A1 US2010147847 A1 US 2010147847A1
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US
United States
Prior art keywords
fuel tank
valve
venting
operational venting
operational
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US12/639,378
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English (en)
Inventor
Klaus Gebert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kautex Textron GmbH and Co KG
Original Assignee
Kautex Textron GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kautex Textron GmbH and Co KG filed Critical Kautex Textron GmbH and Co KG
Assigned to KAUTEX TEXTRON GMBH & CO. KG reassignment KAUTEX TEXTRON GMBH & CO. KG ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: GEBERT, KLAUS
Publication of US20100147847A1 publication Critical patent/US20100147847A1/en
Abandoned legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • 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
    • B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
    • B60K15/03—Fuel tanks
    • B60K15/035—Fuel tanks characterised by venting means
    • B60K15/03519—Valve arrangements in the vent line
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • 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
    • B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
    • B60K15/03—Fuel tanks
    • B60K15/035—Fuel tanks characterised by venting means
    • B60K15/03504—Fuel tanks characterised by venting means adapted to avoid loss of fuel or fuel vapour, e.g. with vapour recovery systems
    • B60K2015/03514—Fuel tanks characterised by venting means adapted to avoid loss of fuel or fuel vapour, e.g. with vapour recovery systems with vapor recovery means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • 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
    • B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
    • B60K15/03—Fuel tanks
    • B60K15/035—Fuel tanks characterised by venting means
    • B60K2015/03561—Venting means working at specific times
    • B60K2015/03571—Venting during driving

Definitions

  • the invention relates to a method of controlling operational venting of a plastics fuel tank and to a plastics fuel tank for a motor vehicle with means for inward and outward venting during fuel discharge (operational venting), having at least one operational venting valve between at least one operational venting point and a fuel vapor filter, the operational venting valve taking the form of a pressure maintaining valve.
  • Non-integrated venting systems normally use separate venting paths for operational venting and refueling venting of the fuel tank.
  • Operational venting of a fuel tank means removing from the tank fuel vapor which arises as a result of surging movements of the fuel, caused by the vehicle's motion and temperature changes, whereas refueling venting of the fuel tank involves conveying the gas volume displaced by the inflowing liquid out of the tank into the atmosphere via a fuel vapor filter, the fuel vapor filter, which conventionally takes the form of an activated carbon filter, becoming fouled with hydrocarbons and waste gas from which all hydrocarbons have been removed being released into the atmosphere.
  • Defouling or back-flushing of the fuel vapor filter normally takes place during driving cycles of the motor vehicle, the combustion air for the internal combustion engine being drawn in via the fuel vapor filter, so resulting in defouling and back-flushing of the fuel vapor filter.
  • venting valves take the form of pressure maintaining valves, which are electrically switchable in order to be able to bring about pressure equalization with the atmosphere prior to initiation of a refueling process.
  • This is conventionally achieved by electrically switched venting valves.
  • the overpressure of the fuel tank admissible as a function of the design of the fuel tank may be for example of an order of 400 mbar, the maximum admissible partial vacuum being around 100 mbar.
  • the object is initially achieved by a method of controlling operational venting of a plastics fuel tank in which the volume of the plastics fuel tank is kept within a predetermined differential range relative to ambient pressure by means of at least one operational venting valve with pressure maintaining function, at least an upper limit of the differential pressure range defining a maximum admissible overpressure being varied as a function of the ambient temperature.
  • the invention proposes ambient temperature-dependent pressure regulation of the fuel tank, whereby account is reliably taken of the changes to the inherent rigidity of the fuel tank arising as a function of the ambient temperature.
  • ambient temperature may be understood for the purposes of the present invention as also meaning the system temperature, i.e. the temperature of the fuel tank determined for example by the conveyance of hot diesel fuel.
  • the fuel in a number of fuel feed systems with fuel return is likewise known to undergo a degree of heating, which contributes to heating of the overall fuel tank system.
  • the upper limit of the differential pressure range is lowered if the ambient temperature exceeds at least a predetermined upper limit, and the upper limit of the differential pressure range is raised if the ambient temperature falls below at least a predetermined lower limit.
  • the upper and lower limits may coincide. However, a lower limit may be provided which deviates from the upper limit, so as to provide switching hysteresis for control system purposes.
  • a preferred variant of the method provides the use of at least one operational venting valve with a temperature-dependent opening and closing characteristic.
  • the admissible differential pressure relative to ambient temperature may amount to between 0 and 500 mbar.
  • the method is particularly preferably performed using an operational venting valve switchable without current and in a temperature-dependent manner.
  • the object underlying the invention is additionally achieved by a plastics fuel tank with means for inward and outward venting during fuel discharge (operational venting), having at least one operational venting valve between at least one operational venting point and a fuel vapor filter, the operational venting valve taking the form of a pressure maintaining valve and the plastics fuel tank being distinguished in that the operational venting valve has an ambient temperature-dependent switching characteristic.
  • the invention should be understood such that the design of the plastics fuel tank may exhibit any desired degree of complexity, wherein operational venting points may be provided at different levels depending on the contour of the plastics fuel tank at a plurality of locations at the top in the installation position. Operational venting systems of the above-described type may be provided at each venting point or also in a central venting manifold.
  • the operational venting valve takes the form of a valve which switches automatically without current.
  • This configuration is particularly advantageous when venting control is to be performed without the vehicle battery. It is conceivable, for example, for the vehicle to be exposed to relatively high ambient temperatures in a repainting chamber, for example, without its battery installed.
  • the valve spring may consist for example of a shape memory alloy, i.e. a “memory metal”. These are alloys which are seemingly able to “remember” an earlier shape despite subsequent severe deformation. A change in shape, once imposed on the material, may be undone for example by heating. The materials used here are then conveniently those which allow a 2-way memory effect, i.e. said metals return to the initial shape on cooling.
  • the operational venting valve comprises at least one valve body held in the closed position under spring loading, at least one valve spring having a temperature-dependent spring constant.
  • the closure force of the operational venting valve may amount to around 100% for example up to an ambient temperature or system temperature of around 50° C., which may correspond to a maximum admissible overpressure of around 400 mbar relative to atmospheric pressure.
  • the closure force of the venting valve may approach 0%, for example, such that the fuel tank is in effect pressureless.
  • the valve spring may take the form of a bimetallic spring.
  • the spring constant of the valve spring varies in accordance with ambient temperature, whereby a temperature-dependent switching characteristic is achieved with the simplest means.
  • the latter comprises a refueling venting means which makes use of a switchable venting path separate from the operational venting.
  • the plastics fuel tank according to the invention conveniently takes the form of a plastics fuel tank for a hybrid motor vehicle.
  • FIG. 1 is a schematic, highly simplified representation of a fuel tank according to the invention.
  • FIG. 2 is a highly simplified, schematic representation of an operational venting valve according to the invention.
  • the fuel tank 1 takes the form of a plastics fuel tank and is provided in a known manner with a filler neck 2 , a refueling vent line, not shown, and at least one operational vent line 3 .
  • the operational vent line 3 communicates via one or more venting points 4 with the equalizing volume 5 of the fuel tank, which is naturally located at the top in the installation position.
  • the equalizing volume 5 is the free gas volume in the fuel tank 1 situated above the liquid volume 6 , which ensures that no liquid hydrocarbons enter the venting system in the event of a change in the volume of the fuel.
  • the operational vent line 3 connected to the equalizing volume 5 is connected to a fuel vapor filter 7 via an operational venting valve 6 .
  • the fuel vapor filter 7 may be constructed in a known manner as an activated carbon filter with one or more volumes containing sorbents.
  • the operational venting valve 6 takes the form of a valve with pressure maintaining function, such that it is ensured that a certain differential pressure range relative to ambient pressure is maintained within the plastics fuel tank 1 . This serves in particular to reduce the tendency of the liquid hydrocarbons to pass into the gaseous phase. In this way it is ultimately possible, in particular in hybrid vehicles, to provide fuel vapor filters with a fouling capacity which does not fundamentally exceed the fouling capacity of a conventional fuel vapor filter despite shorter defouling cycles.
  • the fuel tank 1 according to the invention may be provided with an operational venting valve at each of a plurality of venting points 4 .
  • FIG. 2 is a simplified representation of an example of such an operational venting valve 6 .
  • the outward venting path 8 is closed by means of an outward venting valve 10 and the inward venting path 9 by means of an inward venting valve 11 .
  • the outward venting valve 10 comprises a valve body 10 a , which is held in the closed position by means of a bimetallic spring 10 b .
  • the bimetallic spring 10 b has a spring constant which is designed such that the valve body 10 a is lifted by an overpressure of ⁇ 400 mbar in relation to ambient pressure acting from the side of the equalizing volume 5 off the valve seat designated 10 c and opens up the operational vent line 3 as far as the fuel vapor filter 7 .
  • the spring constant of the bimetallic spring 10 b changes such that the valve body 10 a is lifted from the valve seat 10 c at a lower internal tank pressure, in order to counteract temperature-induced deformation of the plastics fuel tank 1 .
  • the inward venting valve 11 provided in the parallel inward venting path 9 likewise comprises a valve body 11 a , which takes the form of a ball.
  • the valve body 11 a is pressed by means of a compression spring 11 b into the valve seat 11 c , this corresponding to the normal position of the inward venting valve.
  • the inward venting valve 11 opens for example under an atmospheric overpressure of around 100 mbar or with a partial vacuum in the tank of around 100 mbar.
  • outward venting valve also to display an ambient temperature-dependent switching characteristic.
  • a differential pressure range of around ⁇ 100 mbar to +400 mbar, relative to atmospheric pressure is maintained inside the plastics fuel tank 1 by means of one or more operational venting valves 6 , configured as described above.
  • the closing force of the outward venting valve 10 determines the maximum admissible upper limit of the differential pressure range.
  • the closing force of the inward venting valve 11 determines the maximum admissible lower limit of the differential pressure range.
  • the upper limit is variable as a function of ambient temperature due to the properties of the bimetallic spring 10 b of the outward venting valve 10 . At a relatively high ambient temperature the pretension, with which the valve body 10 a is pressed into the valve seat 10 c , is lower, such that in this way temperature-dependent control functioning without current is brought about.

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Cooling, Air Intake And Gas Exhaust, And Fuel Tank Arrangements In Propulsion Units (AREA)
US12/639,378 2008-12-16 2009-12-16 Method of controlling operational venting of a plastics fuel tank and plastics fuel tank Abandoned US20100147847A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102008062243.5 2008-12-16
DE102008062243A DE102008062243A1 (de) 2008-12-16 2008-12-16 Verfahren zur Betriebsentlüftungssteuerung an einem Kunststoff-Kraftstoffbehälter sowie Kunststoff-Kraftstoffbehälter

Publications (1)

Publication Number Publication Date
US20100147847A1 true US20100147847A1 (en) 2010-06-17

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US12/639,378 Abandoned US20100147847A1 (en) 2008-12-16 2009-12-16 Method of controlling operational venting of a plastics fuel tank and plastics fuel tank

Country Status (4)

Country Link
US (1) US20100147847A1 (ja)
EP (1) EP2199138A2 (ja)
JP (1) JP2010143570A (ja)
DE (1) DE102008062243A1 (ja)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102555784A (zh) * 2010-12-21 2012-07-11 F.波尔希名誉工学博士公司 用于机动车辆的压力储箱系统
CN103635682A (zh) * 2011-06-30 2014-03-12 奥迪股份公司 用于运行燃料系统的方法以及燃料系统
US20160016462A1 (en) * 2013-03-07 2016-01-21 Volkswagen Aktiengesellschaft Method for operating a hybrid vehicle
US9447755B2 (en) 2011-06-30 2016-09-20 Audi Ag Method for operating a fuel system, and fuel system

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010055313A1 (de) 2010-12-21 2012-06-21 Audi Ag Verfahren zum Betreiben eines Kraftstoffsystems sowie Kraftstoffsystem
DE102017125283A1 (de) * 2017-10-27 2019-05-02 Alfmeier Präzision SE Ventilsystem für einen Kraftstofftank

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3769952A (en) * 1971-11-16 1973-11-06 Daimler Benz Ag Installation for venting a fuel tank of a motor vehicle provided with expansion tank
US4112891A (en) * 1976-10-21 1978-09-12 General Motors Corporation Temperature compensated internal combustion engine ignition spark vacuum advance system
US4142677A (en) * 1977-06-27 1979-03-06 Tom Mcguane Industries, Inc. Fuel vapor vent valve
US4231342A (en) * 1979-01-29 1980-11-04 General Motors Corporation Diesel fuel heat recovery system and control valve therefor
US5337721A (en) * 1992-08-25 1994-08-16 Aisan Kogyo Kabushiki Kaisha Fuel vapor processing apparatus
US5477829A (en) * 1994-08-08 1995-12-26 Ford Motor Company Automotive returnless fuel system pressure valve
US5715797A (en) * 1995-06-28 1998-02-10 Nippondenso Co., Ltd. Fuel supply system for internal combustion engine and method of adjusting it
US6039030A (en) * 1998-04-06 2000-03-21 Siemens Automotive Corporation Fuel system containing a shape memory alloy
US6360729B1 (en) * 2000-07-20 2002-03-26 Ford Global Technologies, Inc. Active fuel system bladder
US6453885B1 (en) * 1999-12-18 2002-09-24 Delphi Technologies, Inc. Vapor removal fuel containment fuel tank
US20030184023A1 (en) * 2002-04-02 2003-10-02 Nippon Piston Ring Co., Ltd. Piston ring
US6837219B2 (en) * 2003-02-04 2005-01-04 Airtex Products Ported pressure relief valve
US20050241693A1 (en) * 2004-04-30 2005-11-03 Conception Et Developpement Michelin S.A. Gaseous fuel vehicle and automatic vent system
US20060249125A1 (en) * 2005-05-04 2006-11-09 Reddy Sam R Control of induction system hydrocarbon emissions
US7267108B2 (en) * 2005-04-18 2007-09-11 Ford Global Technologies, Llc Fuel system pressure relief valve with integral accumulator
US7441545B1 (en) * 2007-12-12 2008-10-28 Robert Bosch Gmbh Fuel pressure relief valve

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US5036023A (en) * 1989-08-16 1991-07-30 At&T Bell Laboratories Rapid thermal processing method of making a semiconductor device
JP2003113953A (ja) * 2001-10-04 2003-04-18 Kyosan Denki Co Ltd 通気弁構造
DE102007034824A1 (de) * 2007-07-26 2009-01-29 Bayerische Motoren Werke Aktiengesellschaft Betriebsverfahren für ein Tankentlüftungssystem eines Kraftfahrzeugs sowie entsprechendes Tankentlüftungssystem

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3769952A (en) * 1971-11-16 1973-11-06 Daimler Benz Ag Installation for venting a fuel tank of a motor vehicle provided with expansion tank
US4112891A (en) * 1976-10-21 1978-09-12 General Motors Corporation Temperature compensated internal combustion engine ignition spark vacuum advance system
US4142677A (en) * 1977-06-27 1979-03-06 Tom Mcguane Industries, Inc. Fuel vapor vent valve
US4231342A (en) * 1979-01-29 1980-11-04 General Motors Corporation Diesel fuel heat recovery system and control valve therefor
US5337721A (en) * 1992-08-25 1994-08-16 Aisan Kogyo Kabushiki Kaisha Fuel vapor processing apparatus
US5477829A (en) * 1994-08-08 1995-12-26 Ford Motor Company Automotive returnless fuel system pressure valve
US5715797A (en) * 1995-06-28 1998-02-10 Nippondenso Co., Ltd. Fuel supply system for internal combustion engine and method of adjusting it
US6039030A (en) * 1998-04-06 2000-03-21 Siemens Automotive Corporation Fuel system containing a shape memory alloy
US6453885B1 (en) * 1999-12-18 2002-09-24 Delphi Technologies, Inc. Vapor removal fuel containment fuel tank
US6360729B1 (en) * 2000-07-20 2002-03-26 Ford Global Technologies, Inc. Active fuel system bladder
US20030184023A1 (en) * 2002-04-02 2003-10-02 Nippon Piston Ring Co., Ltd. Piston ring
US6837219B2 (en) * 2003-02-04 2005-01-04 Airtex Products Ported pressure relief valve
US20050241693A1 (en) * 2004-04-30 2005-11-03 Conception Et Developpement Michelin S.A. Gaseous fuel vehicle and automatic vent system
US7267108B2 (en) * 2005-04-18 2007-09-11 Ford Global Technologies, Llc Fuel system pressure relief valve with integral accumulator
US20060249125A1 (en) * 2005-05-04 2006-11-09 Reddy Sam R Control of induction system hydrocarbon emissions
US7441545B1 (en) * 2007-12-12 2008-10-28 Robert Bosch Gmbh Fuel pressure relief valve

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102555784A (zh) * 2010-12-21 2012-07-11 F.波尔希名誉工学博士公司 用于机动车辆的压力储箱系统
US9381804B2 (en) 2010-12-21 2016-07-05 Dr. Ing. H.C.F. Porsche Aktiengesellschaft Pressure tank system for a motor vehicle
CN103635682A (zh) * 2011-06-30 2014-03-12 奥迪股份公司 用于运行燃料系统的方法以及燃料系统
US9382878B2 (en) 2011-06-30 2016-07-05 Audi Ag Method for operating a fuel system and fuel system
US9447755B2 (en) 2011-06-30 2016-09-20 Audi Ag Method for operating a fuel system, and fuel system
US20160016462A1 (en) * 2013-03-07 2016-01-21 Volkswagen Aktiengesellschaft Method for operating a hybrid vehicle
US9643484B2 (en) * 2013-03-07 2017-05-09 Volkswagen Aktiengesellschaft Method for operating a hybrid vehicle

Also Published As

Publication number Publication date
JP2010143570A (ja) 2010-07-01
EP2199138A2 (de) 2010-06-23
DE102008062243A1 (de) 2010-06-24

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AS Assignment

Owner name: KAUTEX TEXTRON GMBH & CO. KG,GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:GEBERT, KLAUS;REEL/FRAME:023666/0675

Effective date: 20091127

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION