JP2006188987A - Combustion improver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combustion improver in low temperature starting, particularly using strong oxidation reaction power of an oxygen negative ion, for largely reducing a fuel increase quantity characteristic of starting, by sufficiently promoting combustion even at the low temperature in starting, not by a means such as a temperature rise in an internal combustion engine itself and a temperature rise in suction air. <P>SOLUTION: This combustion improver is characterized by being constituted so that an oxygen negative ion discharge part of an oxygen negative ion generator is connected to an intake manifold upstream part of the internal combustion engine, and the oxygen negative ion generator operates when the internal combustion engine is in warming-up operation, and the oxygen negative ion generator stops when the internal combustion engine is not in the warming-up operation, and being constituted so that an oxygen negative ion is mixed in intake air in at least the warming-up operation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a combustion improving apparatus at low temperature start in an internal combustion engine that promotes combustion of the internal combustion engine and suppresses harmful unburned HC emission as much as possible during warm-up operation immediately after start, and particularly oxygen negative ions. TECHNICAL FIELD The present invention relates to a combustion improving apparatus at a low temperature start using the strong oxidation reaction power of.

  During the warm-up operation immediately after the start of the internal combustion engine, the temperature of the cylinder inner wall and the intake air of the internal combustion engine is low. The fuel is injected. For this reason, a large amount of harmful unburned HC is discharged together with the exhaust gas, and these treatments are a major issue. As a prior art, there is Patent Document 1, and combustion of a combustion heater for raising the temperature of an engine cooling water for use in promoting warm-up of the engine after warming the engine cooling water and exchanging heat at the in-vehicle heater portion in severe cold It has a combustion heater configured to introduce gas directly into the internal combustion engine main body via a bypass passage or to be sent to an intake system via another passage and be introduced into the internal combustion engine together with intake air as combustion gas mixed air Techniques relating to internal combustion engines are presented.

  However, in the above technique, since the combustion gas of the combustion heater is used, the vaporization of the fuel is promoted by the temperature rise and the mixture formation effect is improved. However, the combustion gas is added to the air or the mixture. The concentration is lowered, resulting in deterioration of combustion. Furthermore, there is a drawback that the apparatus such as a combustion heater and a bypass passage is enlarged as a whole.

JP 2000-45770 A

  The present invention is intended to improve the above-mentioned drawbacks of the prior art, and is not a means for increasing the temperature of the internal combustion engine itself or for increasing the temperature of the air-fuel mixture or intake air. Without increasing the size of the system, it can sufficiently promote combustion even at low temperatures at the time of starting, and greatly reduce the amount of fuel specific to starting, especially by utilizing the strong oxidation reaction force of oxygen negative ions The present invention relates to the realization of a high-performance combustion improvement device at the time of cold start.

  The combustion improving apparatus according to claim 1 is characterized in that in the combustion improving apparatus for an internal combustion engine, an oxygen negative ion generator is provided in the intake system of the internal combustion engine so that oxygen negative ions are mixed into the intake air. It is.

In general, oxygen negative ions defined by O ⁻ , O ²⁻ , O ₂ ⁻ , O ₃ ⁻ , and O _n ⁻ are known to have an oxidation capacity about 10,000 times that of oxygen molecules. Yes. Therefore, the ignition limit is expanded, and ignition is possible even with a leaner air-fuel mixture. In addition, since the combustion speed after ignition is high, the effect of promoting fuel vaporization can be expected. As a matter of course, neither the deterioration of combustion nor the increase in size of the apparatus due to the mixing of the combustion gas, which is a drawback of the prior art, is caused.

  According to a second aspect of the present invention, preferably, the oxygen negative ions are mixed at least during the warm-up operation of the internal combustion engine.

  Oxygen negative ions are known to have an oxidation capacity approximately 10,000 times that of oxygen molecules. Therefore, the ignition limit is expanded, and ignition is possible even with a leaner air-fuel mixture. With this configuration, particularly during the warm-up operation at the time of start-up, combustion at a low temperature can be promoted, and the tendency of fuel increase peculiar to start-up can be greatly reduced.

  According to a third aspect of the present invention, the oxygen negative ion generator provided in the intake system is characterized in that an oxygen negative ion release portion of the oxygen negative ion generator is connected to an upstream portion of the intake manifold.

  With this configuration, the oxygen negative ion generator of the compactly configured oxygen negative ion generator is only connected to the upstream portion of the intake manifold without complicatedly incorporating the oxygen negative ion generator into the internal combustion engine. As a result, the entire apparatus can be simply and compactly configured. Since the generated oxygen minus ions have a lifetime of several seconds, it is sufficiently possible to keep the ion state until the start of combustion in the internal combustion engine.

  The apparatus according to claim 4 is characterized in that the oxygen negative ion generator includes a container, an alumina cement constituent material in which at least a part is disposed in the container, and an outer surface of the container is an oxygen negative ion generator, and the alumina A heater for heating the cement component, an oxygen supply electrode formed on at least a part of an inner surface of the alumina cement component, a gas containing at least oxygen gas supplied to the oxygen supply electrode, and the oxygen negative ions An oxygen negative ion extraction electrode installed in the container apart from the generation unit, and a power source capable of applying a voltage higher than the oxygen supply electrode to the oxygen negative ion extraction electrode is there.

  The conventional oxygen negative ion generator requires a high vacuum device and an energy source for discharge, and thus has disadvantages such as an increase in size and power consumption. On the other hand, in a compact type, Although there was a drawback that the amount of oxygen negative ions produced was very small, this configuration eliminates the need for a high vacuum device or an energy source for discharge, and allows compact oxygen and oxygen from alumina cement. Negative ions can be generated stably and continuously. As a result, stable and continuous combustion can be ensured during the warm-up operation at the time of cold start.

  According to a fifth aspect of the present invention, the oxygen negative ion generator includes an internal combustion engine warm-up state detection unit, and the internal combustion engine is warming up based on detection data from the warm-up state detection unit. When it is determined that the power source and the heater drive switch is turned on, and when it is determined that the internal combustion engine is not warming up, the control means for controlling the drive switch to turn off. To do.

  In general, the combustion promotion effect by oxygen negative ions is expected only in a limited operating state, particularly during warm-up operation. Therefore, with this configuration, oxygen negative ions can be generated only when it is confirmed that the engine is warming up, and generation of wasted oxygen negative ions is prevented, resulting in unnecessary consumption. Generation of electric power can be suppressed.

  According to a sixth aspect of the invention, the detection data is a cooling water temperature of the internal combustion engine.

The warm-up operation is performed to increase the temperature of the cylinder inner wall of the internal combustion engine and the intake air. Therefore, it is extremely reasonable and accurate to determine whether or not the engine is in the warm-up operation based on the cooling water temperature state of the internal combustion engine.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 conceptually shows the overall configuration of the internal combustion engine system, and oxygen minus is present in the intake pipe 4 of the internal combustion engine (engine) 1, specifically, in the intake pipe 4 at a position immediately upstream of the intake manifold. The whole image figure of the combustion improvement apparatus in the internal combustion engine which connected the oxygen-negative ion discharge | release part 3 of the ion generator 2 which concerns on this invention is shown.

  FIG. 2 is an enlarged view of the oxygen negative ion generator 2 shown in FIG. Reference numeral 2 denotes an oxygen negative ion generator, an alumina cement constituent 5 that can contain oxygen negative ions, a container 8 that holds the alumina cement constituent 5, a heater 9 that heats the alumina cement constituent 5, and an alumina cement. An oxygen supply electrode 6 provided in the structure 5, a gas 12 containing at least oxygen gas supplied to the oxygen supply electrode 6, and an extraction electrode 10 for extracting oxygen negative ions from the alumina cement structure 5; And a power source 11 that can apply a higher voltage to the extraction electrode 10 than the oxygen supply electrode 6.

  As shown in FIG. 2, the alumina cement structure 5 is formed as a cylindrical body having one end closed by, for example, pressure molding and firing, and the closed one end side is disposed in the container 8. Yes. An oxygen supply electrode 6 is formed on at least a part of the inner surface of the alumina cement structure 5, and a gas 12 containing at least oxygen gas is supplied to the oxygen supply electrode 6 as will be described later. Electrons are supplied from the power supply 11. The oxygen supply electrode 6 is formed, for example, by applying a metal paste inside the alumina cement structure 5 and sintering it, and is formed porous so that the supplied oxygen can react with the alumina cement. Further, the outer surface of the closed end of the alumina cement constituting body 5 in the container 8 is an oxygen negative ion generating portion 7. Furthermore, the alumina cement structure 5 is heated to 650 ° C. or more by the heater 9 and is not shown in the figure, but the temperature of the alumina cement is controlled by using an appropriate temperature sensor conventionally used.

  The container 8 is made of stainless steel, glass or the like, and the internal atmosphere is kept in a vacuum or filled with an inert gas such as argon, but is preferably kept dry.

  As shown in the drawing, the extraction electrode 10 is arranged at a predetermined distance d from the oxygen negative ion generator 7. Further, the extraction electrode 10 is made of a stainless steel plate or the like, and a hole is provided at the center thereof so that the generated oxygen negative ions can pass.

  The power source 11 is a power source that applies a voltage higher than that of the oxygen supply electrode 6 to the extraction electrode 10 in order to extract the oxygen negative ions 14 from the alumina cement, and may be either direct current or alternating current. Reference numeral 13 denotes a drive switch for turning on / off the power.

Next, a method for generating oxygen negative ions will be described. As a first step, it is preferable that the alumina cement constituting body 5 is heated by the heater 9 and heated to 650 ° C. or higher, for example, 700 to 810 ° C. When the temperature of the alumina cement constituent 5 is at least 650 ° C. or more, as a second stage, the switch 13 of the power source 11 is turned on, so that the voltage between 100 and 2500 V is provided between the extraction electrode 10 and the oxygen supply electrode 6. While applying a voltage, the gas 12 containing oxygen gas is supplied to the oxygen supply electrode 6. For this reason, electrons are supplied from the oxygen supply electrode 6 and exchange of electrons occurs between the O ⁻ , O ²⁻ , and O ₂ ⁻ ions contained in the alumina cement, and so-called ion conduction occurs. As a result, oxygen negative ions 14 are generated from the oxygen negative ion generator 7 and released to the outside, and pass through the hole of the extraction electrode 10. On the other hand, the amount of oxygen negative ions stored in the alumina cement decreases because of the release of oxygen negative ions from the oxygen negative ion generator 7, but the gas 12 containing oxygen gas is used as the oxygen supply electrode. 6 is supplied to the alumina cement and reacts to compensate for the decrease.

Next, the relationship between the amount of oxygen negative ions generated and the temperature of the alumina cement will be described. According to the experimental data when the applied voltage is 375 V, oxygen negative ions start to be generated when the temperature of the alumina cement component 5 is approximately 650 ° C., and the current density starts to increase linearly when the temperature exceeds 700 ° C. At 810 ° C., the current density of oxygen negative ions was 0.25 μA / cm ² .

Further, the relationship between the amount of oxygen negative ions generated and the applied voltage will be described. According to the experimental data when the temperature of the alumina cement component 5 is 800 ° C., oxygen negative ions are generated when the electric field strength is 35 V / cm, 0.1 μA / cm ² is generated at 100 V / cm, and around 500 V / cm. The current density started to increase linearly from 1100, 1700, and 2130 V / cm, and were 1, ² , 2.7 μA / cm ² , respectively.

  Further, the current density of the generated oxygen negative ions by the oxygen negative ion generator 2 according to the present invention is about 2000 times or more compared with the current density of the generated oxygen negative ions by the solid electrolyte material YSZ (stabilized zirconia) of the conventional example. It has become.

  By the way, conventionally, during the warm-up operation immediately after starting the internal combustion engine, the temperature of the cylinder inner wall and the intake air of the internal combustion engine is low, so that the injected fuel is not sufficiently vaporized and the air-fuel ratio is improved even a little. More fuel injection than usual is performed. For this reason, a large amount of harmful unburned HC is discharged to the outside together with the exhaust gas.

  In order to solve this problem, it depends on how to shorten the start-up time in order to prevent HC from being discharged from the internal combustion engine as much as possible at the time of start-up, and how to make complete combustion at the time of start-up.

  The present invention relates to a combustion improving device at a low temperature start in an internal combustion engine that promotes combustion of the internal combustion engine and suppresses harmful unburned HC emission as much as possible during the warm-up operation immediately after the start. The present invention relates to a combustion improving apparatus at the time of low temperature start using the strong oxidation reaction force of oxygen negative ions generated by the oxygen negative ion generator 2 described above.

  FIG. 4 shows the relationship between the air-fuel ratio and the combustion speed when oxygen negative ions are mixed into the intake air using the combustion improving apparatus according to the present invention and when oxygen negative ions are not mixed into the intake air. It is the image figure which showed. As is apparent from the figure, in all cases, the combustion speed is the highest when the air-fuel ratio is 1.0, but all the empty air is less when oxygen negative ions are mixed in the intake air than when the air is not mixed. It can be seen that the combustion speed is overwhelmingly high at the fuel ratio.

  On the other hand, a large amount of HC is a problem during the warm-up operation, and in the steady operation state, the conventional exhaust gas treatment centering on the DPF can sufficiently cope. Therefore, as a matter of course, it is not necessary to always generate oxygen negative ions and mix them with the intake air during operation, and it is wasteful by managing and controlling so that oxygen negative ions can be generated only during the warm-up operation. Oxygen negative ions are prevented from being generated, and as a result, generation of useless power consumption is suppressed.

  FIG. 3 is a flowchart relating to operation control of the oxygen negative ion generator 2 by an ECU (not shown), and will be described along the respective stage numbers S1 to S5. At the same time when the internal combustion engine (engine) 1 is started, the oxygen negative ion generator 2 is started, and the engine operating state data such as the engine speed and the fuel injection amount and the engine coolant temperature data are measured in the engine system. It is always transferred to the ECU (S1, 2).

  Next, during the warm-up operation, the ECU compares the preset engine coolant temperature, which is the criterion for the warm-up operation, and the coolant temperature data transferred from the engine system every moment. If it is determined (S3), the switch 13 of the power source 11 and the switch of the heater 9 (not shown) are turned on, and oxygen negative ions are generated (S4). On the other hand, when it is determined that the warm-up operation is not being performed, the switch 13 of the power supply 11 and the switch of the heater 9 are turned off, and the generation of oxygen negative ions is stopped (S5). In addition, it is preferable that the cooling water temperature of the engine, which is a predetermined criterion for the warm-up operation, is 60 ° C.

Thus, since this invention is the above structures, there exist the following effects.
In general, oxygen negative ions defined by O ⁻ , O ²⁻ , O ₂ ⁻ , O ₃ ⁻ , and O _n ⁻ are known to have an oxidation capacity about 10,000 times that of oxygen molecules. Yes. Therefore, the ignition limit is expanded, and ignition is possible even with a leaner air-fuel mixture. In particular, during the warm-up operation at the start, combustion at a low temperature can be promoted, and the fuel increase specific to the start can be greatly reduced. Further, since the combustion speed after ignition is high, an effect of promoting fuel vaporization can be expected. As a matter of course, neither the deterioration of combustion nor the increase in size of the apparatus due to the mixing of the combustion gas, which is a drawback of the prior art, is caused.
Furthermore, the oxygen negative ion generator of the compactly constructed oxygen negative ion generator is only connected to the upstream side of the intake manifold without complicatedly incorporating the oxygen negative ion generator into the internal combustion engine. Can be simply and compactly configured. Since the generated oxygen minus ions have a lifetime of several seconds, it is sufficiently possible to maintain the ion state until the start of combustion in the internal combustion engine.
In addition, it is possible to generate oxygen negative ions only when it is confirmed that the engine is warming up, preventing generation of wasted oxygen negative ions, and consequently suppressing generation of wasted power consumption. it can.

1 is a schematic configuration diagram of an internal combustion engine system that incorporates a combustion improving apparatus according to an embodiment of the present invention. 1 is an overall configuration diagram of an oxygen negative ion generator in an embodiment of the present invention. It is a flowchart about the operation control regarding the oxygen negative ion generator of the combustion improvement apparatus in embodiment of this invention. It is the image figure which showed the relationship between the combustion speed of the combustion improvement apparatus in embodiment of this invention, and an air fuel ratio.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Oxygen negative ion generator 3 Oxygen negative ion discharge part 4 Intake pipe 5 Alumina cement component 6 Oxygen supply electrode 7 Oxygen negative ion generator 8 Container 9 Heater 10 Extraction electrode 11 Power supply 12 Gas containing oxygen gas 13 Switch 14 Oxygen negative ion

Claims (6)

  A combustion improving apparatus for an internal combustion engine comprising an oxygen negative ion generator in an intake system of the internal combustion engine so that oxygen negative ions are mixed into the intake air.   The combustion improving apparatus according to claim 1, wherein the oxygen negative ions are mixed at least during the warm-up operation of the internal combustion engine.   The combustion improvement apparatus according to claim 1 or 2, wherein the oxygen negative ion generator provided in the intake system has an oxygen negative ion generator connected to an upstream portion of the intake manifold.   The oxygen negative ion generator includes a container, an alumina cement constituent material at least part of which is disposed in the container and having an outer surface serving as an oxygen negative ion generator, and a heater for heating the alumina cement constituent material. An oxygen supply electrode formed on at least a part of the inner surface of the alumina cement constituent material, a gas containing at least an oxygen gas supplied to the oxygen supply electrode, and the oxygen negative ion generating part spaced apart from the above 4. An oxygen negative ion extraction electrode installed in a container, and a power source capable of applying a higher voltage than the oxygen supply electrode to the oxygen negative ion extraction electrode. Combustion improvement apparatus as described in one.   The oxygen negative ion generator includes a warm-up state detection unit for the internal combustion engine, and when the internal combustion engine is determined to be in a warm-up operation based on detection data from the warm-up state detection unit, 5. A control means for turning on the drive switch of the heater and turning off the drive switches when it is determined that the internal combustion engine is not warming up. The combustion improvement apparatus as described in one.   6. The combustion improving apparatus according to claim 5, wherein the detected data is a cooling water temperature of the internal combustion engine.

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