Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/0047—Layout or arrangement of systems for feeding fuel
  • F02M37/0052—Details on the fuel return circuit; Arrangement of pressure regulators
  • F02M37/0058—Returnless fuel systems, i.e. the fuel return lines are not entering the fuel tank
• • 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
  • B60K15/06—Fuel tanks characterised by fuel reserve systems
  • B60K15/061—Fuel tanks characterised by fuel reserve systems with level control
• • 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
  • B60K15/077—Fuel tanks with means modifying or controlling distribution or motion of fuel, e.g. to prevent noise, surge, splash or fuel starvation
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
  • G01F23/14—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measurement of pressure
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
  • G01F23/14—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measurement of pressure
  • G01F23/18—Indicating, recording or alarm devices actuated electrically
• • 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
  • B60K2015/0321—Fuel tanks characterised by special sensors, the mounting thereof
  • B60K2015/03217—Fuel level sensors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D33/00—Controlling delivery of fuel or combustion-air, not otherwise provided for
  • F02D33/003—Controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus ; Failure or leakage prevention; Diagnosis or detection of failure; Arrangement of sensors in the fuel system; Electric wiring; Electrostatic discharge
  • F02D33/006—Controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus ; Failure or leakage prevention; Diagnosis or detection of failure; Arrangement of sensors in the fuel system; Electric wiring; Electrostatic discharge depending on engine operating conditions, e.g. start, stop or ambient conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/0076—Details of the fuel feeding system related to the fuel tank
  • F02M37/0082—Devices inside the fuel tank other than fuel pumps or filters
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/04—Feeding by means of driven pumps
  • F02M37/08—Feeding by means of driven pumps electrically driven
  • F02M37/10—Feeding by means of driven pumps electrically driven submerged in fuel, e.g. in reservoir
  • F02M37/106—Feeding by means of driven pumps electrically driven submerged in fuel, e.g. in reservoir the pump being installed in a sub-tank
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/8158—With indicator, register, recorder, alarm or inspection means
  • Y10T137/8326—Fluid pressure responsive indicator, recorder or alarm

Definitions

• the invention relates to a level measuring device for a fuel tank of a motor vehicle according to the preamble of claim 1.
• Such a fill level measuring device is known from DE 39 14 637 AI.
• This fill level measuring device has a measuring tube arranged in the fuel tank, which extends from the bottom of the fuel tank to at least the height of the maximum fill level of the fuel tank and is conveyed into the fuel.
• the level measuring device also has a differential pressure sensor, which is connected with its one measuring input to the lower end of the measuring tube and with its other measuring input is exposed to the liquid pressure at the bottom of the fuel tank.
• the measuring tube has an overflow opening which is arranged at least at the level of the maximum fill level of the fuel tank. The measuring tube can be emptied through an opening located near the bottom of the fuel tank or a valve to the level of the current fill level of the fuel tank.
• the fill level is determined in an evaluation device from the difference between the output signals of the differential pressure sensor with the measuring tube filled up to the overflow opening and with the current fill level of the Fuel tank emptied measuring tube.
• the delivery of fuel into the measuring tube takes place via a return line through which fuel that is not used by the internal combustion engine of the motor vehicle is returned to the fuel tank. The one through the
• Return line fuel flowing may be heated so that there is a temperature difference between the fuel in the measuring tube and the fuel in the fuel tank, which in turn results in a difference in the density of the fuel in the measuring tube compared to the density of the fuel in the fuel tank, which leads to Errors in the output signals of the differential pressure sensor.
• fuel delivery systems are also known in which there is no return flow from the internal combustion engine to
• Fuel tank is present, so that the known level measuring device can not be used.
• the fill level measuring device according to the invention for a fuel tank of a motor vehicle has the advantage that the fuel fed into the measuring tube is not heated and that use in fuel delivery systems without return is possible.
• FIG. 1 shows a fuel tank of a motor vehicle with the level measuring device arranged therein according to a first embodiment with a filled measuring tube
• FIG. 2 shows the fuel tank with the level measuring device with an empty measuring tube
• FIG. 3 shows the fuel tank with the level measuring device according to a second embodiment.
• a fill level measuring device 12 is arranged, which serves to determine the fill level of the fuel tank 10, which is shown in a known manner on a display instrument 34 arranged in the driver's field of vision.
• the fill level measuring device 12 has a vertically extending measuring tube 14 arranged in the fuel tank 10, the cross section of which is considerably smaller than the cross section of the fuel tank 10.
• the measuring tube 14 can be made of plastic or metal, for example, and extends from the bottom 16 of the fuel tank 10 to close to the ceiling 18. Near its upper end 20, the measuring tube 14 has an overflow opening 22 which opens into the fuel tank 10.
• the fill level measuring device 12 also has a differential pressure sensor 24 arranged in the fuel tank 10.
• the differential pressure sensor 24 has two measurement inputs
• a measuring input 26 being connected to the lower end 30 of the measuring tube 14 and thus being acted upon by the hydrostatic pressure of the liquid column in the measuring tube 14.
• the other measuring input 28 of the differential pressure sensor 24 is connected to the bottom 16 of the fuel tank 10 and thus acted upon by the hydrostatic pressure of the liquid column in the fuel tank 10.
• the signal output of the differential pressure sensor 24 is connected to an evaluation device 32, which in turn controls the display instrument 34.
• a micro-mechanical pressure sensor which is particularly inexpensive, is preferably used as the differential pressure sensor 24.
• a delivery unit 40 is arranged in the fuel tank 10, through which fuel is delivered from the fuel tank 10 to the injection system 44 of an internal combustion engine 46 of the motor vehicle.
• the conveyor unit 40 has a pump part 41 and a drive part 42, which is preferably designed as an electric motor.
• the delivery unit 40 is held in a manner not shown in the fuel tank 10, wherein a pot 48 can be provided in the fuel tank 10, from which the delivery unit 40 sucks fuel.
• the pot ensures that the delivery unit 40 can deliver sufficient fuel even when the fuel tank 10 is low.
• Fuel can be conveyed from the fuel tank 10 into the pot 48 by a jet pump or another pump.
• Operation of the internal combustion engine 46 is not continuously operated with the same delivery rate, but rather the operation of the delivery unit 40 is controlled or regulated in such a way that the amount of fuel consumed in the current operating state of the internal combustion engine 46 is conveyed through this.
• the electrical power supplied to the drive part 42 of the conveyor unit 40 or the electrical voltage applied to it can be varied. Due to this demand-controlled operation of the conveyor unit 40, there is no return for the Internal combustion engine 46 requires unused fuel in the fuel tank 10.
• a pressure regulator 45 is arranged in the fuel tank 10 which has an inlet which is connected to the pressure side of the delivery unit 40 and which has an outlet which is connected to the injection system 44 Internal combustion engine 46 is connected, and which has a return 47 which opens into the fuel tank 10.
• the pressure regulator 45 adjusts an at least approximately constant fuel pressure in the injection system 44. In this embodiment, too, no return line from the internal combustion engine 46 to the fuel tank 10 is required.
• the pressure regulator 45 can, for example, together with the delivery unit 40
• Fuel tank 10 may be held or, as shown in FIG. 1, on a cover 38 closing an opening 36 of the fuel tank 10.
• Fuel line 50 for connection to the injection system 44 From the fuel line 50 or directly from the pressure side of the delivery unit 40, for example from a connection piece 52 of the delivery unit 40, a further fuel line 54 branches off into the measuring tube 14
• Level measuring device 12 opens near its lower end 30.
• the fuel line 54 opening into the measuring tube 14 has a substantially smaller cross-section than the fuel line 50 leading to the injection system 44.
• the fuel line 54 opening into the measuring tube 14 is thus throttled relative to the fuel line 50 leading to the injection system 44, so that one of the delivery unit 40 much larger amount of fuel is delivered to the injection system 44 than in the measuring tube 14. If the delivery unit 40 is operated, it delivers fuel to the injection system 44 via the fuel line 50 and delivers fuel into the measuring tube 14 via the fuel line 54.
• the measuring tube 14 is filled with fuel until it lo in height
• Overflow opening 22 is, as shown in Figure 1. With further fuel delivery into the measuring tube 14, the fuel flows back into the fuel tank 10 via the overflow opening 22. When the delivery unit 40 is operating, a fuel column with the defined height lo is thus set in the measuring tube 14, which has a defined hydrostatic pressure at the first measuring input 26 Differential pressure sensor 24 causes. The second measurement input 28 of the differential pressure sensor 24 is the one through the fuel column with the height h of the fuel in
• Fuel tank 10 exposed to hydrostatic pressure.
• the current height h of the fuel column in the fuel tank 10 is the fill level of the fuel tank 10.
• the output signal u (t) of the differential pressure sensor 24 is therefore proportional to the
• the output signal u (t) of the differential pressure sensor 24 is fed to the evaluation device 32, which determines the output signal h (t) from it according to the following equation:
• g is the acceleration due to gravity
• t> the density of the fuel
• k the transmission factor (sensitivity) of the differential pressure sensor 24.
• uo is the output signal of the differential pressure sensor 24 for the condition that the height of the liquid column in the measuring tube 14 is equal to the height h of the fuel in the fuel tank 10 is. This state occurs when the conveyor unit 40 is not operating becomes. In this case, the measuring tube 14 runs empty from the level of the fuel to the overflow opening 22 at the height lo up to the current height h of the fuel in the fuel tank, as shown in FIG. 2.
• FIGS. 1 and 2 show the fill level measuring device 12 according to a first embodiment, in which, when the delivery unit 40 is switched off, fuel can flow out of the measuring tube 14 through the fuel line 54 and the delivery unit 40 into the fuel tank 10.
• the measuring tube 14 near its lower end 30 or the fuel line 54 has a small opening 56 through which fuel can flow out of the measuring tube 14 into the fuel tank 10.
• the opening 56 is dimensioned in such a way that less fuel can flow through it in a certain time unit than fuel is conveyed into the measuring tube 14 by the delivery unit 40 during its operation in this time unit.
• the output signal uo of the differential pressure sensor present in this state 24 represents its offset. This offset is subject to a certain drift during the life of the differential pressure sensor 24, which would impair the accuracy of the level measurement. This offset is taken into account in the evaluation device 32 in accordance with the equation given above, so that it does not lead to errors in the determination of the fill level.
• the output signal uo of the differential pressure sensor 24 can in each case be determined after the delivery unit 40 has been switched off and stored in the evaluation device 32. After each shutdown of the conveyor unit 40, the for Output signal uo stored value can be updated.
• the fill level signal h (t) determined by the evaluation device 32 is continuously displayed on the display device, not shown.
• FIG. 3 shows the fill level measuring device 12 according to a second exemplary embodiment, the basic structure being the same as in the first exemplary embodiment.
• a valve 60 is arranged in the fuel line 54 between the delivery unit 40 and the measuring tube 14.
• the valve 60 is between a first position shown in solid lines in FIG. 3, in which it connects the measuring tube 14 to the delivery unit 40 via the fuel line 54, and a second position, shown in FIG. 3 with dashed lines, in which the fuel line 54 opens and connects the measuring tube 14 to the fuel tank 10, switchable.
• the valve 60 can be designed as a solenoid valve that is electrically switchable. The switchover of the valve 60 between its two positions can be controlled by the evaluation device 32. Normally, the valve 60 is in the operation of the delivery unit 40 in the position in which the measuring tube 14 is connected to the delivery unit 40 and thus is filled with fuel up to the level lo, so that by the
• the current fill level h of the fuel tank 10 can be determined.
• the valve 60 is switched to its other position in order to connect the measuring tube 14 to the fuel tank 10 and to determine the output signal uo of the differential pressure sensor 24 and thus to compensate for the zero point drift. This switchover of the valve 60 can not only take place when the internal combustion engine 46 is switched off Conveyor unit 40 take place, but also during the operation of the conveyor unit 40th
• valve 60 can also be designed in such a way that the one in this position
• Fuel line 54 is released and the fuel line 54 is blocked in its other position.
• an opening 14 is provided in the fuel line 54 between the valve 60 and the measuring tube 14 or in the region of the lower end 30 of the measuring tube 14 in order to enable the measuring tube 14 to be emptied.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• General Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Physics & Mathematics (AREA)
• Sustainable Energy (AREA)
• Transportation (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• General Engineering & Computer Science (AREA)
• Cooling, Air Intake And Gas Exhaust, And Fuel Tank Arrangements In Propulsion Units (AREA)
• Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=7851559

Family Applications (1)

Country Status (8)

Families Citing this family (20)

Family Cites Families (6)

• 1997
  • 1997-12-11 DE DE19755056A patent/DE19755056A1/de not_active Withdrawn
• 1998
  • 1998-06-26 KR KR1019997006891A patent/KR20000070642A/ko not_active Application Discontinuation
  • 1998-06-26 CN CN98802456A patent/CN1105295C/zh not_active Expired - Fee Related
  • 1998-06-26 BR BR9807571-3A patent/BR9807571A/pt not_active IP Right Cessation
  • 1998-06-26 EP EP98937410A patent/EP0966655A1/de not_active Withdrawn
  • 1998-06-26 WO PCT/DE1998/001746 patent/WO1999030115A1/de not_active Application Discontinuation
  • 1998-06-26 US US09/341,660 patent/US6164325A/en not_active Expired - Fee Related
  • 1998-06-26 JP JP52960299A patent/JP2001511258A/ja active Pending

Non-Patent Citations (1)

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