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
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/45—Sensors specially adapted for EGR systems
  • F02M26/48—EGR valve position sensors
• • 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
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/52—Systems for actuating EGR valves

Definitions

• the invention relates to an exhaust gas recirculation system of an internal combustion engine with an exhaust gas recirculation valve having a housing with an inlet for the supply of exhaust gas of the internal combustion engine and at least one outlet for the return of a portion of the exhaust gas into the combustion air supply of the internal combustion engine, wherein a connection between the inlet and the at least one outlet of a valve body can be released or interrupted and an actuating system with actuator and valve body is provided, wherein the actuator moves the valve body to enable the connection between the inlet and the at least one outlet or interrupt, according to the features of the preamble of claim 1.
• Exhaust gas recirculation is used to reduce nitrogen oxides that are produced during combustion of fuel in internal combustion engines, such as gasoline or diesel engines. This reduction is necessary in order to comply in particular with the emission limit values prescribed today. In diesel engines, they also serve to reduce noise, whereas in gasoline engines due to the exhaust gas recirculation to reduce fuel consumption is possible. At high combustion temperatures arise in the engine increasingly polluting nitrogen oxides. In order to reduce this, the combustion temperature must be lowered, so that a part of the exhaust gas of the Internal combustion engine is therefore mixed in the partial load range via a connection to the intake of the internal combustion engine sucked fresh air.
• exhaust gas recirculation valve external exhaust gas recirculation
• exhaust gas recirculation installed outside the engine, which has an inlet to which the exhaust gas of the internal combustion engine is supplied and which has a valve body, as a function of which the exhaust gas is supplied to the intake tract of the internal combustion engine, so that the part of the exhaust gas in the partial load range of the intake fresh air can be mixed.
• exhaust gas recirculation exhaust gas recirculation valves are already known to which the exhaust gas is supplied from the combustion tract of the internal combustion engine, wherein by means of the exhaust gas recirculation valve, a portion of the exhaust gas via one or two outlets of the exhaust gas recirculation valve is supplied to the Ansaus Tha the internal combustion engine.
• These exhaust gas recirculation valves have an actuator, which is operated by a control unit in dependence on the parameters of the internal combustion engine. It can thus be regulated in which amount the exhaust gas recirculation valve supplied to the exhaust tract of the internal combustion engine can be supplied.
• Known exhaust gas recirculation valves have a housing having an inlet, wherein one or two outlets are further provided.
• the inlet for the exhaust gas and the outlet or the two outlets are arranged approximately at right angles to each other, wherein within the housing by a movable actuator piston rod is mounted on the spaced apart two discs are arranged in the interior of the cylindrical Housing are arranged movable.
• Older exhaust gas recirculation valves consist of bypass flap and exhaust gas recirculation valve. They thus include the sensors for detecting the position of the valve body within the exhaust gas recirculation valve as well as two actuators. This effort is reflected in the costs.
• valve flaps valve body
• actuators such as pressure cans or vacuum cans
• the valve flap is arranged on a piston, this of an actuator such.
• an electric or hydraulic actuator is moved.
• PLCD displacement sensors permanent magnetic linear contactless displacement
• the object is therefore to provide a measuring system for an exhaust gas recirculation system of an internal combustion engine which measures the direct position of the valve body or the position of the actuator in the exhaust gas recirculation system.
• the valve body in a generic exhaust gas recirculation system, is associated with a magnetic measuring system having a sensor element to detect the position of a magnet located in the positioning system linear contact.
• the magnetic measuring system is designed such that it is realized as Relativweg measurement.
• the choice of the magnetic measuring system has the advantage that it detects linearly the position of a magnet located in the adjustment system without contact. In this case, conventionally absolute measuring sensors and conventional magnets are out of consideration because of the large temperature differences in the total exhaust gas recirculation system.
• the magnetic measuring system which is used according to the invention is based on an angle-measuring sensor principle.
• the appropriate selection of the Magnets, the arrangement of the components, the geometry with large distances, the integration of the magnet in the adjustment system and the application area in the high-temperature region of the engine compartment of vehicles are of particular advantage here.
• the required high accuracy can thus be achieved even with extreme temperature differences between the sensor element and the exhaust gas recirculation system.
• the magnet is arranged on a piston of the pressure-reducing or vacuum-formed actuator of the exhaust gas recirculation system and the magnet is associated with a magnetic sensor element.
• the magnet is introduced in a direction of magnetization suitable for the movement of the piston.
• the adjustment paths of the system are in the order of magnitude, for example, from 1 mm (millimeters) to 50 mm (millimeters). If the magnet arranged on the piston is moved by the actuator, the angles of the magnetic field vectors change relative to the magnetic sensor element, for example a Hall element, so that the angle-measuring sensor principle can be realized on the basis of this arrangement.
• the change in the angle of the magnetic field vectors can be evaluated via a downstream control unit with suitable algorithms, so that, for example, for an engine control of an engine of a vehicle always the exact measure or the exact position of the position of the actuator and its elements in the exhaust gas recirculation system is known. It is also advantageous that compared to the known system cheaper magnets can be used and temperature fluctuations (temperature drifts) cause no deterioration of the signal quality. As magnets come, for example, conventional Permanent magnets into consideration, whereby plastic magnets which are magnetizable, come into consideration.
• the advantages of the measuring system according to the invention are that operating temperature ranges up to 160 degrees Celsius can be realized and that large temperature differences are possible within the system.
• the measurement accuracy is approximately 0.1 mm, with mechanical tolerances (manufacturing or assembly tolerances) are negligible.
• the measuring system according to the invention for the exhaust gas recirculation system is not only used there but generally in actuators and sensors with linear motion in a more difficult environment application, for example in special adjustment systems in the engine, exhaust, axle or powertrain of vehicles.
• the calibration for eliminating installation tolerances can for example take place in that the actuator moves with the piston and the magnet thereon in a first position, preferably first stop or end position, and detects this position and a corresponding signal is generated. Subsequently, the piston is moved to a second position, preferably the second stop or end position, and in turn generates a signal for this position.
• the two detected signals are detected in the downstream control unit and thus provide the absolute path or one depending on the algorithm
• Adjustment range that can be normalized. Due to this standardization, it is possible to take into account or eliminate the installation tolerances, as well as the later occurring possible aging of the magnet, so that this measuring system is very versatile.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Exhaust-Gas Circulating Devices (AREA)
• Fluid-Driven Valves (AREA)

Applications Claiming Priority (1)

Publications (2)

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ID=41279444

Family Applications (1)

Country Status (2)

Cited By (2)

Family Cites Families (4)

• 2009
  • 2009-08-28 EP EP09011029A patent/EP2159405A3/fr not_active Withdrawn
  • 2009-08-28 DE DE102009039019A patent/DE102009039019A1/de not_active Withdrawn

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