Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N11/00—Starting of engines by means of electric motors
  • F02N11/08—Circuits specially adapted for starting of engines
  • F02N11/087—Details of the switching means in starting circuits, e.g. relays or electronic switches
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/22—Safety or indicating devices for abnormal conditions
  • F02D2041/228—Warning displays
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2400/00—Control systems adapted for specific engine types; Special features of engine control systems not otherwise provided for; Power supply, connectors or cabling for engine control systems
  • F02D2400/11—After-sales modification devices designed to be used to modify an engine afterwards
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N11/00—Starting of engines by means of electric motors
  • F02N11/08—Circuits specially adapted for starting of engines
  • F02N11/0814—Circuits specially adapted for starting of engines comprising means for controlling automatic idle-start-stop
  • F02N11/0818—Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode
  • F02N11/0825—Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode related to prevention of engine restart failure, e.g. disabling automatic stop at low battery state
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2250/00—Problems related to engine starting or engine's starting apparatus
  • F02N2250/02—Battery voltage drop at start, e.g. drops causing ECU reset

Definitions

• the invention relates to a method for driving a starter relay in a motor vehicle, wherein the starter relay is controlled by an engine control unit for starting a motor and the engine control unit is reset at a collapse of a battery voltage.
• the starter relay is actuated again and thereby supplies the starter with working voltage.
• this usually leads to a renewed collapse of the electrical system and a repetition of the process until the battery is finally empty.
• These cycles take about 250 ms, so they are not interpreted by the user of the motor vehicle as a malfunction. The user merely realizes that the engine is not starting although there is still enough battery capacity for about 10 to 20 starts.
• engine control units which are voltage-resistant to a drop in the supply voltage to 6 V, ie, that they still work properly at this low voltage and the starter relay is held in the attracted state to activate the starter.
• additional circuits under the term “power boost circuit” are known, which compensate for a drop in the operating voltage up to 4.5 V and allow a correct startup.
• these voltage-resistant motor control units or the additional power-boost circuits are In the purchase very expensive, which is why they are often omitted for cost reasons.
• the object is achieved in that the starter relay is driven such a second start that a starter starts an engine of the motor vehicle.
• the essence of the invention is that as soon as due to the collapse of the battery voltage, an engine control unit automatically shuts off or resets this is registered by an additionally present in the motor vehicle electronic circuit. As soon as the on-board voltage has recovered after usually 250 ms or the usual operating voltage is present again and the engine control unit re-activates the starter relay, this circuit is activated to prevent the starter relay from being reset due to a re-collapsing on-board voltage and the subsequent shutdown of the engine control unit becomes. With this additional circuit, the starter relay is controlled such that it remains in any case in the attracted state and thus the starter is still supplied with operating voltage, even if the engine control unit turns off. For this purpose, the necessary working voltage is supplied to the starter relay of the circuit.
• this additional circuit can be configured in any manner that can be carried out by a person skilled in the art, but this is preferably done as described below.
• This circuit can be present, for example, as an additional electronic component in the motor vehicle, inter alia, as a circuit in the vehicle electronics. In principle it is but also possible to implement this circuit in an existing engine control unit hardware and / or software.
• the advantage of the invention is that the method can be carried out in a simple manner with a cost-effective circuit and can be dispensed with expensive additional circuits.
• By controlling the starter relay a proper execution of a startup process is ensured even with an automatic reset of the engine control unit with decreasing battery capacity.
• the control of the starter relay with a known to those skilled flip / flop circuit that switches between two states back and forth.
• This circuit can either be provided as a separate circuit in the engine electronics or integrated in the engine control unit but also in another element of the vehicle electronics.
• a suitably dimensioned flip-flop circuit, which controls the starter relay even when the engine control unit is reset so that the starter is still supplied with operating voltage, can be designed by the skilled person in a suitable manner.
• the circuit is designed such that when terminating the boot process, z. B. when the ignition key is turned back after the start of the user back to the normal operating position, is reset to its original output value, in particular the starter relay no longer from the flip / flop circuit to control.
• a corresponding signal can be forwarded, for example, from the ignition lock via data bus architectures in the motor vehicle to the circuit or the engine control unit.
• the flip / flop circuit for controlling the starter relay an optical and / or acoustic display, wherein the display means are controlled for example by a central control unit for controlling all functions in the motor vehicle, which in turn is connected via data buses to the circuit.
• a voice message "low battery” may be output.
• a corresponding message can be output on a display of an on-board computer or a flashing or flashing signal.
• the already existing battery light may flash several times to alert the user to the weakening battery. This can then recharge the battery either by a long drive on the highway or visit a workshop to change the battery.
• An important advantage of the invention is that, by the timely information (warning) of the user, the overall electronic system - especially the engine control units - designed less voltage resistant and thus both defines the warning areas and costs can be saved. By using the available information also a consumer shutdown and thus a simplified battery management is possible.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)
• Control Of Direct Current Motors (AREA)

Applications Claiming Priority (1)

Publications (2)

Family

ID=35511961

Family Applications (1)

Country Status (2)

Cited By (4)

Family Cites Families (5)

• 2004
  • 2004-10-07 DE DE200410048808 patent/DE102004048808A1/de not_active Withdrawn
• 2005
  • 2005-08-11 EP EP05017448A patent/EP1645752A3/fr not_active Withdrawn

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