Internal-combustion engines – With heating means
Reexamination Certificate
2000-06-29
2002-06-04
Argenbright, Tony M. (Department: 3747)
Internal-combustion engines
With heating means
C123S567000
Reexamination Certificate
active
06397807
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an internal combustion engine having a combustion heater and, more particularly, to an internal combustion engine having a combustion heater for introducing a combustion gas into an intake system of the internal combustion engine in order to speed up warm-up of the internal combustion engine.
2. Related Background Art
An internal combustion engine mounted in a vehicle such as an automobile, etc. is constructed to operate at a high efficiency within a predetermined temperature range. The reason is that an engine fuel such as gasoline, a light oil, etc. is hard to evaporate at, e.g., a low temperature with the result that there arise troubles such as a starting characteristic is impaired and so on, because of the difficulty of igniting those fuels, and hence those troubles should be prevented.
Further, as known well, an interior of a car room can be warmed by utilizing the heat evolved in the internal combustion engine when the engine works, but can not be warmed if a heating value is insufficient.
Such being the case, for instance, Japanese Patent Application Laid-Open Publication No. 60-79149 discloses a technology of utilizing the combustion heat of the combustion heater incorporated into the internal combustion engine for the purpose of speeding up warm-up of the engine and enhancing a performance of a car room interior warming device.
According to this technology, a high-temperature combustion gas of the combustion heater is introduced into an intake pipe of the internal combustion engine, and intake air of the engine is heated by this combustion gas, thereby facilitating actuation of the engine even when the internal combustion engine is in a low-temperature state.
The combustion gas emitted from the combustion heater is, however, an exhaust gas emitted when burning the fuel. The exhaust gas has a less oxygen content than an oxygen content in the air before being used for the combustion.
Therefore, as by the technology disclosed in the above Publication, when introducing the combustion gas into the intake pipe, if scheming to increase a ratio of the combustion gas contained in the intake air flowing through the intake pipe by augmenting the quantity of the combustion gas, though the warm-up of the engine is speeded up, a ratio of oxygen content in the intake air might decrease on the contrary.
As explained above, when the ratio of the oxygen content in the intake air decreases, a quantity of the combustion within the cylinders is restricted, resulting in such a state that the starting characteristic of the internal combustion engine might decline. The situation being so, if reducing the ratio of the combustion gas introduced into the intake pipe in order to ensure the oxygen quantity, this might in turn lead to an insufficient warm-up of the engine, and the starting characteristic is still impaired.
Especially at the engine starting time, since a crank shaft is rotated by an engine start assisting device such as a starter motor, etc., the engine speed is as low as, e.g., 100-200 rpm, and there is a small amount of intake air sucked into the cylinders from the atmospheric air via the intake pipe. Accordingly, there increases the ratio of the combustion gas in almost all intake air taken-in.
Therefore, the intake air containing the combustion gas at such a high ratio is absolutely unable to be used as engine intake air, and, in an extreme case, there is a possibility that the engine does not work.
SUMMARY OF THE INVENTION
It is a primary object of the present invention, which was devised under such circumstances, to provide an internal combustion engine having a combustion heater for raising a temperature of intake air of the internal combustion engine by introducing a combustion gas evolved when burning a fuel into the internal combustion engine and utilizing the heat held by the combustion gas, whereby a starting characteristic of the internal combustion engine is enhanced by positively replenishing oxygen to attain a sufficient oxygen content in the engine intake air while improving warm-up of the internal combustion engine.
To accomplish the above object, the present invention adopts the following means.
(1) An internal combustion engine having a combustion heater for raising a temperature of intake air of the internal combustion engine by utilizing combustion heat held by a combustion gas emitted when burning a fuel, and a combustion gas introducing passageway, through which a combustion gas discharge port of the combustion heater is connected to an engine intake passageway, for introducing the combustion gas into the intake passageway, comprising an oxygen supplying device for supplying oxygen to the engine intake air having become the intake air containing the combustion gas when the combustion gas is introduced via the combustion gas introducing passageway into the engine intake passageway, and an oxygen supply quantity control unit for controlling a quantity of oxygen supplied by the oxygen supplying device, and wherein the oxygen supply quantity control unit executes, at the engine starting time or before the engine starting time and also introducing the combustion gas into the engine intake passageway at that time, an augmentation control of augmenting the quantity of oxygen supplied to the engine intake air by the oxygen supplying device, the oxygen content in the engine intake air that is decreased due to the introduction of the combustion gas into the intake passageway, is supplemented under the augmentation control, and this supplement makes the engine intake air the intake air with oxygen content effective in enhancing a starting characteristic of the internal combustion engine.
Herein, what can be exemplified as “the oxygen supply quantity control unit” may be an ECU (electronic control unit) serving as an engine control unit for controlling operations of the whole internal combustion engine. In this case, an optimum oxygen content corresponding to an operation state of the internal combustion engine can be supplied under the control by the ECU.
The term “the engine starting time” implies a state where a crank shaft is rotated by an engine start assisting device such as, e.g., a starter motor or the like which is attached to the engine body, and a piston makes a reciprocating motion within the cylinder, namely in a cranking state, thereby the internal combustion engine eventually becomes independent enough to start its operation without depending on the starter motor.
The term “before the engine starting time” indicates the time before or preferably immediately before the engine (crank shaft) is rotated by the engine starting assisting device such as the starter motor, etc.
The term “starting characteristic” is, as a matter of course, a condition of how the internal combustion engine works and implies how easily the internal combustion engine independently starts operating.
The term “the intake air with oxygen content effective in enhancing the starting characteristic of the internal combustion engine” indicates a value obtained beforehand by a test performed for every internal combustion engine.
(2) The oxygen supplying device supplies the engine intake passageway with the oxygen through the combustion gas introducing passageway.
(3) The oxygen supplying device may be an air blow device capable of making an air quantity variable, and the air blow device may be an air blow fan for supplying the combustion heater with the air for combustion.
(4) The air blow fan includes a fan, a driving unit for rotationally driving the fan, and a fan rotational speed control device for controlling the rotational speed of the fan by controlling an operation of the driving unit. The fan rotational speed control device sets, at the engine starting time or before the engine starting time, the rotational speed of the fan higher than that in operation other than the starting time of the internal combustion engine. What can be exemplified as the fan rotational speed control device may
Argenbright Tony M.
Harris Katrina B.
Kenyon & Kenyon
Toyota Jidosha & Kabushiki Kaisha
LandOfFree
Internal combustion engine having combustion heater does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Internal combustion engine having combustion heater, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Internal combustion engine having combustion heater will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2934838