Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
  • F01L9/20—Valve-gear or valve arrangements actuated non-mechanically by electric means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B1/00—Engines characterised by fuel-air mixture compression
  • F02B1/02—Engines characterised by fuel-air mixture compression with positive ignition
  • F02B1/04—Engines characterised by fuel-air mixture compression with positive ignition with fuel-air mixture admission into cylinder

Definitions

• the invention relates to a method for operating an internal combustion engine according to the preamble of claim 1.
• Such an internal combustion engine is known for example from DE-OS 302k 109.
• the one or more gas exchange valves of the internal combustion engine are held in their closed position by an electromagnet being excited and attracting an armature plate.
• a spring system presses in the opening direction of the valve, so that when the electromagnets are switched off, the spring system becomes effective and the valve opens.
• the electromagnet is switched on, however, the force of the electromagnet is large enough to hold the armature plate in the closed position of the valve despite being acted upon by the spring system.
• the invention has for its object to operate an internal combustion engine equipped with a generic gas exchange valve such that the energy expenditure is lower.
• the valve is subjected to a force which additionally pushes it into its valve seat and thus in the closing direction. During the application of this force can thus' the th through the Magne ⁇ expended holding force is reduced since the magnet must compensate only the spring force minus the action by the cylinder pressure on the valve plate force now.
• the current flow through the electromagnet is controlled, the degree of current flow being dependent on the internal cylinder pressure.
• the internal cylinder pressure is difficult to measure as a direct measured variable, but empirical values are available which make statements about the time course of the internal cylinder pressure. It is therefore appropriate, according to a preferred embodiment, to control the current flow through the electromagnet in a time-dependent manner, the magnitude of the current flow resulting from the empirically determined course of the internal pressure in the cylinder during a combustion process or compression process.
• the ignition timing is a suitable parameter for synchronizing the time course of the current flow through the electromagnet, since the ignition increases the internal pressure due to the ignition of the mixture inside the cylinder.
• the ignition point thus defines the starting point for the chronological sequence of the internal cylinder pressure.
• Fig. 2 is a working diagram for a reciprocating engine in the four-stroke principle to explain the invention.
• the method according to the invention can be used in an internal combustion engine as disclosed in DE-OS 30 24 109.
• the following is essential for the valve arrangement:
• a cylinder head 10 closes the cylinder interior 12 from above, in which the combustion processes, as take place in an internal combustion engine, take place in a known manner.
• a valve 14 is provided, which is shown in FIG. 1 in the open position, ie lifted off the valve seat.
• the valve 14 carries on its valve stem 16 an armature plate 18 which can oscillate back and forth between the pole faces of a magnet 20 and a magnet 22 in the axial direction of the valve stem 16.
• the valve 14 is closed. However, the valve 14 is not moved by one attraction on the pole face of the magnet to the pole face of the other magnet by magnetic attraction, but a spring system 24, 25, 26, 27 is provided, the springs 24 and 25 being the armature plate 18 push away from the contact position on the pole face of the magnet 22, while the springs 26 and 27 push the anchor plate 18 away from the contact position on the pole faces of the magnet 20.
• the zero point of this spring system is such that when the magnets 20 and 22 are not energized, the armature plate 18 is located approximately in the middle between the pole faces of the magnets 20 and 22.
• the magnet 20 is therefore energized in order to keep the armature plate 18 in contact with the pole face of the magnet 20, although the armature plate 18 with the force of the spring 26 and 27 is applied, which intend to push the anchor plate 18 away from the pole face. If the current is now switched off by the magnet 20, the armature plate 18 is accelerated by the springs 26 and 27, which is braked after contact with the springs 24 and 25, but extends so far that the armature plate 18 at least almost until it touches the pole face of the magnet 22. If the magnet 22 is now energized at this time, the armature plate 18 is held by the pole faces of the magnet 22, the valve 14 closes.
• the size of the current must be dimensioned so that the force of the springs 24 and 25 is compensated for.
• FIG. 2 shows the working diagram of a four-stroke internal combustion engine, in a known manner an ignitable mixture is drawn in in cycle I, in cycle II, which is between 180 ° and 360 ° crankshaft angle, that is between bottom dead center and top Dead center, the mixture is compressed to be ignited shortly before reaching top dead center.
• cycle I in cycle II, which is between 180 ° and 360 ° crankshaft angle, that is between bottom dead center and top Dead center
• the mixture is compressed to be ignited shortly before reaching top dead center.
• the internal pressure reaches up to 40 bar; in diesel internal combustion engines, it can be significantly higher, for example three times the value.
• the burned mixture is expelled in work cycle IV.
• the current flow will not be controlled depending on the absolute value of the crankshaft angle, but rather the control will try to be synchronized with the ignition point.
• the reduction of the holding current through the coil of the electromagnet 22 can start at a certain point in time after the ignition point, best expressed in degrees crankshaft angle, since this measure is independent of the number of revolutions, and, depending on the engine properties, can then be maintained for about 100 ° crankshaft angle. * It is possible to control the temporal course of the current during these 100 ° crankshaft angles, or to lower it only to a lower value.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Valve Device For Special Equipments (AREA)
• Output Control And Ontrol Of Special Type Engine (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6275009

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (17)

Citations (2)

Family Cites Families (9)

• 1985
  • 1985-07-05 DE DE19853524024 patent/DE3524024A1/de not_active Withdrawn
• 1986
  • 1986-06-24 ES ES556519A patent/ES8706898A1/es not_active Expired
  • 1986-06-25 US US07/019,242 patent/US4846120A/en not_active Expired - Lifetime
  • 1986-06-25 JP JP61503632A patent/JPS62502056A/ja active Granted
  • 1986-06-25 EP EP86904140A patent/EP0229792B1/de not_active Expired
  • 1986-06-25 DE DE8686904140T patent/DE3660557D1/de not_active Expired
  • 1986-06-25 WO PCT/EP1986/000376 patent/WO1987000239A1/de not_active Ceased

Patent Citations (2)

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