JP4048032B2 - Fuel supply device and internal combustion engine equipped with the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel supply device for an automobile internal combustion engine and an internal combustion engine equipped with the same, and aims to improve the startability of the internal combustion engine and to reduce harmful substances discharged from the internal combustion engine, particularly HC. The present invention relates to a technique suitable for the above.
[0002]
[Prior art]
Promoting atomization of fuel spray injected by a fuel injection valve (injector) and reducing adhesion to the inner wall of an intake pipe as means for improving startability, improving fuel efficiency and purifying exhaust gas, particularly reducing HC in an internal combustion engine Is effective. Further, combustion stability can be achieved by atomizing the fuel spray.
[0003]
In order to supply fuel spray with increased atomization to an internal combustion engine, it is known to provide a fuel injection valve (injector) that is used auxiliaryly when starting the internal combustion engine. USP 5,482,023 specification and drawings describe a cold start fuel control system including a cold start fuel injector, a heater, and an idle speed control valve (hereinafter referred to as an ISC valve). In this system, a part of the air from the ISC valve (first air flow) is merged with the fuel injected from the cold start fuel injector. For this purpose, the opening of the air passage from the ISC valve is provided in an annular shape so as to surround the outlet of the cold start fuel injector. The fuel and the first air flow from the cold start fuel injector are put into a cylindrical heater arranged in a line on the downstream side of the cold start fuel injector immediately after the merge. On the other hand, an air passage through which a part of the air from the ISC valve flows is formed in the outer periphery of the heater, and the air (second air flow) flowing through this air passage is inside the heater at the outlet of the heater. It merges with the fuel spray that has passed through. The fuel discharged from the cold start fuel injector is promoted to vaporize when passing through the inside of the heater, and further vaporized by being mixed with the second air flow at the outlet of the heater.
[0004]
[Problems to be solved by the invention]
In the conventional system, by forming a mixing chamber for mixing fuel and air inside the cylindrical heater, the cold start fuel injector, the fuel injected from the cold start fuel injector and the first air flow from the upstream side are arranged. A mixing chamber configured inside the heater and the heater is arranged in a row, and constitutes one atomizer (atomizer) having the heater outlet as the outlet. This atomizer is an air-assisted atomizer using the energy of air flow, and is an internal mixing type atomizer that combines fuel and air inside the atomizer to mix gas and liquid. it is conceivable that.
[0005]
In this system, while the fuel is injected, the fuel spray always comes into contact with the inner wall surface of the mixing chamber, that is, the inner wall surface of the heater. For this reason, the burden of the heater in atomization of fuel spray becomes large, and the consumed electric power also becomes large.
[0006]
An object of the present invention is to provide a fuel spray injected from a liquid fuel injection valve. By spraying the fuel so as to be surrounded by the carrier gas Promotes atomization of With The purpose is to reduce the electric energy consumed by the heater and, in some cases, eliminate the need for the heater. Another object is to improve the reliability and durability of the heater by reducing the electric energy consumed by the heater.
[0007]
[Means for Solving the Problems]
The present invention includes a fuel atomization device that atomizes a fuel spray injected from a liquid fuel injection valve to cause atomization, and the atomized fuel spray is disposed downstream of the throttle valve in an intake pipe having a throttle valve. In the fuel supply device to be supplied, the fuel atomization device has an atomization that opens around the liquid fuel injection hole of the fuel injection valve and acts on the fuel spray injected from the liquid fuel injection hole to promote atomization. A first gas passage for injecting a gas, and a second gas for injecting a carrier gas into the fuel spray so as to surround the fuel spray whose atomization is promoted by the atomized gas, and generating an air-fuel mixture A passage and a heater installed so as to be positioned around the transport passage of the air-fuel mixture; The second gas passage has an annular opening that faces the injection direction of the fuel spray around a central axis that passes through the center of the liquid fuel injection hole of the fuel injection valve and is hypothesized in the fuel injection direction. By forming a gas passage formed on the outer side of a cylindrical guide extending toward the downstream so as to cover the outer periphery of the fuel spray so as to be formed on the outer side of the part, The atomization gas promotes atomization of the fuel spray, and the fuel spray promoted by atomization is transported so as to be surrounded by the carrier gas, thereby reducing the burden on the heater and reducing the amount of fuel adhering to the wall surface. is there.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the intake air is used as the atomized gas for promoting atomization of the fuel spray and the carrier gas for conveying the atomized fuel spray.
[0009]
FIG. 1 is a schematic diagram of an ignition type internal combustion engine equipped with a fuel supply device of the present invention and operated using gasoline as fuel.
[0010]
The internal combustion engine 1 includes a combustion chamber 54 disposed with a spark plug 53 facing, an intake hole 55 for taking a mixture of air and fuel into the combustion chamber 54, an intake valve 44 for opening and closing the intake hole 55, and a post-combustion And an exhaust valve 58 for opening and closing the exhaust hole 59. The internal combustion engine 1 further includes a water temperature sensor 56 that detects the temperature of engine cooling water at the side of the combustion chamber 54, and a rotation sensor (not shown) at the bottom, and is configured to detect the operating state. Yes.
[0011]
The intake system that takes in the combustion chamber 54 includes an air cleaner 46, an air flow sensor 11, a throttle valve 4 and a throttle sensor 52 that constitute an intake control device, and an intake pipe 5. The intake pipe 5 includes an intake manifold 3 and an intake manifold 47 connected to the intake hole 55. The intake manifold 47 branches from the intake manifold 3 toward a plurality of cylinders, but FIG. 1 shows one cylinder.
[0012]
The fuel supply device for the internal combustion engine 1 in this embodiment includes a first fuel supply device and a second fuel supply device. The first fuel supply device is configured by a first liquid fuel injection valve 2 provided upstream of the intake valve 44 of each cylinder and downstream of the intake manifold 3. The first liquid fuel injection valve 2 is attached to the wall portion of the intake manifold 47 and injects fuel toward the upstream side of the intake valve 44 that opens and closes the intake hole 55.
[0013]
The second fuel supply device 100 is installed upstream of the intake manifold 3 in the intake system. This second fuel supply device 100 is provided in the middle of an intake pipe 5 having a built-in throttle valve 4, intake bypass pipes 5a and 5b branched from the intake pipe 5 upstream of the throttle valve 4, and an intake bypass pipe 5b. The ISC valve 73 and a second liquid fuel injection valve 9 for injecting fuel in common to each cylinder are provided, and the atomization of the fuel spray 6 injected from the second liquid fuel injection valve 9 is bypassed by intake air. The air that has passed through the pipes 5a and 5b is promoted and an air-fuel mixture is generated and supplied to the intake manifold 3. The intake bypass pipes 5a and 5b may be configured so that the upstream part is formed in common and branches in the middle (downstream part). The second fuel supply device 100 mainly functions to supply fuel during the warm-up idling operation, the fuel supply amount is controlled by the second liquid fuel injection valve 9, and the intake air amount is the ISC valve 73. Control by.
[0014]
The first liquid fuel injection valve 2 is attached to the wall portion of the intake manifold 47 and injects fuel in the direction of the intake valve 44. The second liquid fuel injection valve 9 operates for a predetermined time when the internal combustion engine 1 is warmed up. The first and second liquid fuel injection valves 2 and 9 use electromagnetic fuel injection valves, and control the fuel injection amount based on the opening and closing times of the internal valves and valve seats. The fuel injection amount is controlled by an engine control unit (hereinafter referred to as an ECU) 57 according to the operation state such as the intake air amount detected by the signal from the sensor. The first and second liquid fuel injection valves 2 and 9 are upstream swirling fuel injection valves, and include a member (fuel swirling member) that imparts a swirling force to the fuel upstream of the valve seat. Injection is performed while swirling the fuel passing through the liquid fuel injection hole provided on the downstream side of the seat. This forms a cone-shaped fuel spray with excellent atomization.
[0015]
The intake air flow supplied to the internal combustion engine 1 is accurately measured and measured using the air flow sensor 11, the throttle valve 4, the throttle sensor 52, the ISC valve 73, and the like. The throttle valve 4 is an intake control member that changes the amount of air flowing in the intake pipe 5 by changing the ventilation area that is turned in the intake pipe 5 and projected onto the cross section of the intake pipe 5.
[0016]
The exhaust system includes an exhaust manifold 48, an oxygen concentration sensor 50 that measures the oxygen concentration in the exhaust gas, a three-way catalytic converter 51 for exhaust gas purification, a muffler muffler (not shown), and the like.
[0017]
The three-way catalytic converter 51 purifies NOx, CO, and HC exhausted from the internal combustion engine 1 operated near the theoretical air-fuel ratio with a high purification rate.
[0018]
Prior to the start of the internal combustion engine 1, the fuel supply system pressurizes the fuel (gasoline) 41 in the fuel tank 40 by the fuel pump 42, and the first fuel injection valve 2 and the second fuel injection through the filter 43. Pumped to the valve 9 at a predetermined pressure. The fuel pressure is adjusted by the pressure regulator 45 so that a constant pressure difference is obtained with respect to the intake pipe pressure.
[0019]
In the above configuration, in the combustion chamber 54, the mixture of the fuel injected from the first and second liquid fuel injection valves 2 and 9 and the intake air 10 is sucked in the suction stroke, and the sucked mixture is compressed in the compression stroke. After being compressed, the spark plug 53 is ignited and burned. The exhaust 26 discharged from the internal combustion engine 1 in the exhaust stroke is released from the exhaust system into the atmosphere.
[0020]
Next, the configuration of the second fuel supply apparatus 100 will be described in detail with reference to FIG. FIG. 2 is an enlarged vertical side view of the second fuel supply device 100.
[0021]
The downstream end of the intake bypass pipe 5a is connected to the pressure regulating chamber 101a, and the intake air 10a is supplied to the pressure regulating chamber 101a as atomized air. The intake bypass pipe 5b includes an ISC valve 73 in the middle thereof. The midway of the intake bypass pipe 5b includes its inlet and outlet sections. For example, an ISC valve 73 may be provided between the outlet section (downstream end) of the intake bypass pipe 5b and the pressure regulating chamber 101b. . The downstream end of the intake bypass pipe 5b is connected (communication) to the pressure regulating chamber 101b, and supplies the intake air 10b to the pressure regulating chamber 101b as carrier air. The pressure regulating chambers 101a and 101b are separated from each other by a partition wall 101c.
[0022]
The atomizer base member 102 is connected downstream of the pressure regulating chambers 101a and 101b. In this embodiment, the atomizer base member 102 is formed in a cylindrical shape, and a cylindrical throttle 17 and a heater 70 are connected to the downstream side thereof to form an air-fuel mixture generating chamber 140 on the inside thereof.
[0023]
The atomizer base member 102 includes an atomization gas passage 102a and a carrier gas passage 102b, and the pressure regulating chambers 101a and 101b communicate with the atomization gas passage 102a and the carrier gas passage 102b, respectively.
[0024]
The atomizer base member 102 is provided with a fuel injection valve fitting hole 102c connected to the upstream side of the air-fuel mixture generating chamber 140 on the inner side, and a gas-liquid mixed injection nozzle is disposed in the fuel injection valve fitting hole 102c. 130, the injection valve holder 120, and the second liquid fuel injection valve 9 are fitted concentrically so as to be sequentially located inside.
[0025]
The atomized gas passage 102 a communicates with the nozzle passage 103 provided in the gas-liquid mixing injection nozzle 130. The nozzle passage 103 is formed by an inner wall surface (inner circumferential surface) 133 of the gas-liquid mixing injection nozzle 130, an outer wall surface (outer circumferential surface) 121 of the injection valve holder 120, and a front end surface 24 a of the liquid injection nozzle 24 of the liquid fuel injection valve 9. The atomized gas passage 7, which is a configured annular gap, is communicated. The front end surface 24 a of the liquid injection nozzle 24 of the liquid fuel injection valve 9 has a liquid fuel injection hole (not shown) at the center thereof, and this front end surface 24 a is used as a part of the passage wall of the atomizing gas passage 7. As a result, the opening of the atomization gas passage 7 is brought close to the fuel injection hole of the liquid fuel injection valve 9, and the intake air 10a for atomization effectively acts on the start end of the fuel spray 6 injected from the liquid fuel injection valve 9. It is configured so that it can be made.
[0026]
Further, as will be described later, when a turning force is applied to the injected fuel in the liquid fuel injection valve 9, the turning radius of the fuel spray 6 increases as the distance from the fuel injection hole of the liquid fuel injection valve 9 increases. 7 is opened along the tip end surface 24a of the liquid injection nozzle 24 of the liquid fuel injection valve 9 close to the fuel injection hole, whereby the length of the atomized gas passage 7 in the radial direction can be increased. Ki This is advantageous when directing the atomized air flow. In addition, since the gas-liquid mixing injection hole 12 of the gas-liquid mixing injection nozzle 130 following the atomized gas passage 7 can be made smaller, the degree of design freedom with respect to other sizes of the gas-liquid mixing injection hole 12 is increased accordingly. Become.
[0027]
The gas-liquid mixing injection nozzle 130 has a gas-liquid mixing injection hole 12 at a position facing the front end surface 24a of the liquid fuel injection valve 9, and the downstream end of the atomized gas passage 7 is gas-liquid mixing injection from the opening. It communicates with an inner wall surface (inner circumferential surface) 134 of a cylindrical guide 131 extending downstream from the gas-liquid mixing injection nozzle 130 through the hole 12. The gas-liquid mixing injection hole 12 forms a thin-blade orifice, and the length of the parallel part of the gas-liquid mixing injection hole 12 with respect to the flow direction of the fuel spray 6 and the atomized air 10a flowing through the gas-liquid mixing injection hole 12 is set. We make it as small as possible. Further, the gas-liquid mixing injection hole 12 has a shape in which the passage cross-sectional area is enlarged toward the downstream, and is formed into a shape connected to the inner wall surface (inner peripheral surface) 134 of the guide 131 after being enlarged. The guide 131 is formed such that an inner peripheral surface 134 and an outer peripheral surface 135 thereof have a predetermined length L and are parallel to the flow direction.
[0028]
The carrier gas passage 102 b is a carrier that is an annular gap formed by the inner wall surface (inner circumferential surface) 150 of the atomizer base member 102, a part of the outer wall surface 132 of the gas-liquid mixing nozzle 130 and the outer wall surface 135 of the guide 131. The gas passage 8 is communicated.
[0029]
The atomizing gas passage 102a and the carrier gas passage 102b are structured to join upstream of the throttle 17 coupled to the atomizer base member 102 downstream through the atomizing gas passage 7 and the carrier gas passage 8 which are annular gaps, respectively. . The diaphragm 17 has a diaphragm shape in which the cross-sectional area of the passage decreases as it goes downstream. A cylindrical heater 70 in which a passage for the fuel spray 6 is formed inside is coupled to the inside of the throttle 17 further downstream. The heater 70 is installed so that its outlet communicates with the intake manifold 3.
[0030]
Basically, the fuel spray 6 injected from the liquid fuel injection valve 9 is atomized and gas-liquid mixed by the atomized air 10a, the carrier air 10b, and the heater 70 to efficiently generate an air-fuel mixture and downstream. Constitutes a fuel atomization device to be conveyed (supplied) to
[0031]
Next, the flow of the intake air 10 will be described.
[0032]
1 and 2, when the internal combustion engine 1 rotates, the intake pipe 5 including the intake manifold 3 has a predetermined negative pressure. The intake air 10 taken in from the outside due to the negative pressure in the intake pipe 5 is filtered by passing through the air cleaner 46, and then the intake air amount is measured by the air flow sensor 11 and reaches the upstream side of the throttle valve 4. . During start-up and idling operation, most of the intake air 10 flows into the intake bypass pipes 5a and 5b as atomized air 10a and carrier air 10b and reaches the ISC valve 73.
[0033]
The ISC valve 73 controls the flow rate of the carrier air 10b flowing through the intake bypass pipe 5b. Since the throttle valve 4 is closed (fully closed) when the internal combustion engine 1 is started and idling, the required flow rate of the intake air 10 is controlled by the ISC valve 73. Further, the flow rate of the carrier air 10b is extremely large relative to the flow rate of the atomized air 10a, and is a flow rate that can cover the amount of intake air required at the time of starting and idling. Therefore, the idling operation of the internal combustion engine 1 can be realized by controlling the flow rate of the carrier air 10b without controlling the flow rate of the atomized air 10a.
[0034]
Part of the intake air 10 flows into the combustion chamber 54 as intake air 10c due to leakage from a very small gap between the throttle valve 4 and the intake pipe 5 even when the throttle valve 4 is fully closed. . However, the amount of the intake air 10c is negligibly small compared to the amounts of the atomized air 10a and the carrier air 10b.
[0035]
In this embodiment, the intake bypass pipes 5a and 5b are respectively branched from the intake pipe 5. However, these paths may be combined into one path without being independent. In this case, the partition wall 101c that partitions the pressure regulating chambers 101a and 101b is omitted to form one pressure regulating chamber. Thereby, the atomization gas passage 102a and the conveyance gas passage 102b communicate with the same pressure regulating chamber. Further, the ISC valve 73 is provided in the middle of the intake bypass pipe combined into one. The middle of the intake bypass pipe includes an inlet portion and an outlet portion thereof. For example, an ISC valve 73 may be provided between the outlet portion (downstream end portion) of the intake bypass pipe and the pressure regulating chamber.
[0036]
In this embodiment, the supply pressure of the atomized air 10a at the time of start and idling is maintained at a predetermined pressure by the configuration of the intake bypass pipes 5a and 5b and the mounting position of the ISC valve 73. . When the intake bypass pipes 5a and 5b are combined into one bypass pipe, the carrier air 10b and the atomized air 10a are in a steady state in the carrier gas passage 8 and the atomized gas passage 7 by controlling the intake air amount of the ISC valve 73. It may not be supplied with. However, in the case of this embodiment, the flow rate of the carrier air 10b is controlled by the ISC valve 73, but since the atomized air 10a is not controlled, it can be supplied in a steady state. Therefore, the atomized air 10a can effectively act on the fuel spray 6, and the promotion of atomization can be stabilized.
[0037]
Next, the flow of the intake air 10a downstream of the ISC valve 73 will be described.
[0038]
The intake air 10b controlled by the ISC valve 73 flows into the pressure regulating chamber 101b having a predetermined space. The intake air 10b that has flowed into the pressure regulating chamber 101b flows into the carrier gas passage 102b as the carrier air 10b that mainly plays the role of conveying the fuel spray 6 downstream. The diversion ratio between the atomized air 10a and the carrier air 10b is determined by the ratio of the gas-liquid mixture injection holes 12 provided in the gas-liquid injection nozzle 130 and the passage sectional area of the carrier gas passage 102b.
[0039]
When the intake bypass pipes 5a and 5b are combined into one bypass pipe, the intake air controlled by the ISC valve 73 flows into one pressure regulation chamber having a predetermined space, and atomized air 10a. The carrier air 10b is divided into the atomized gas passage 102a and the carrier gas passage 102b, respectively. Here, also in this case, the diversion ratio between the atomized air 10a and the carrier air 10b is determined by the gas-liquid mixture injection hole 12 provided in the gas-liquid mixture injection nozzle 130 and the passage cross-sectional area ratio of the carrier gas passage 102b. The
[0040]
The atomized air 10 a flows into the atomized gas passage 7 through the nozzle passage 103. The atomized air 10a flowing through the atomized gas passage 7 is supplied so as to uniformly surround the entire circumference of the start end portion of the fuel spray 6 along the tip surface 24a of the liquid injection nozzle 24 as indicated by an arrow in FIG. After being merged, the gas passes through the gas-liquid mixing injection hole 12 and is injected into the guide 131 downstream of the gas-liquid mixing injection nozzle 130.
[0041]
The fuel spray 6 is supplied at a predetermined flow rate and flow rate so that the gas-liquid mixture injection nozzle 130 and the shape of the gas-liquid mixture injection hole 12 and the atomized air 10a uniformly surround the fuel spray 6 from the entire circumference. As a result, the gas-liquid mixture injection holes 12 are not attached to the gas-liquid mixture injection holes 12 and are efficiently supplied into the mixture generation chamber 140. Then, the atomized air 10 a and the fuel spray 6 supplied to the air-fuel mixture generation chamber 140 proceed to the throttle 17 through the guide 131. During this time, the atomized air 10 a joins the fuel spray 6 to promote atomization and gas-liquid mixing of the fuel spray 6.
[0042]
The carrier air 10b is supplied from the carrier gas passage 102b to the carrier gas passage 8 that is an annular gap, and is supplied from the rear end of the outer periphery of the guide 131 to the air-fuel mixture generation chamber 140. Flows so as to wrap the air 10 a from the outer periphery and reaches the throttle 17.
[0043]
The fuel spray 6, the atomized air 10 a, and the carrier air 10 b that have joined together while being squeezed by the restrictor 17 become smaller as the cross-sectional area of the passage in the restrictor 17 decreases downstream. In addition, the conveyance capacity is improved. Therefore, since the fuel spray 6 in which atomization and gas-liquid mixing are promoted by the atomized air 10a is conveyed so as to be wrapped from the entire circumference by the conveying air 10b, the amount of adhesion to the wall surface in each part Can be reduced and can be supplied into the cylindrical heater 70.
[0044]
Coarse particles are also present in the atomized and mixed fuel spray 6. The coarse particles are not transported to the combustion chamber 54 along the flow of the intake air (the atomized air 10a and the transported air 10b), and fall halfway and adhere to the inner wall surface of the intake pipe. In other words, coarse particles have a short flight distance. As a countermeasure, the coarse particles collide with the heater 70 or pass through the heater 70 to promote atomization and vaporization and reduce the amount of adhesion to the inner wall surface of the intake pipe.
[0045]
The effect of the length L of the guide 131 of the gas-liquid mixing injection nozzle 130 will be described.
[0046]
The fuel spray 6 injected from the upstream swirling liquid fuel injection valve 9 forms a cone-shaped spray, and atomization is promoted as it proceeds downstream. By increasing the length L of the guide 131, the outlet portion of the carrier air 10b (carrier gas passage 8) to the mixture generation chamber 140 is brought closer to the downstream portion where the atomization of the fuel spray 6 is further promoted. Can do. Accordingly, the carrier air 10b can be efficiently supplied into the air-fuel mixture generating chamber 140 at a predetermined flow rate, so that the carrying capacity for the fuel spray 6 is increased and the fuel spray 6 can be carried further downstream. Become.
[0047]
Further, by shortening the length L of the guide 131, the distance between the outlet of the carrier air 10b into the mixture generation chamber 140 and the fuel spray 6 is increased, and the supply of the carrier air 10b supplied to the fuel spray 6 is achieved. The speed is lowered, and the conveying capacity for the fuel spray 6 is lowered. However, when the flow of the carrier air 10b approaches the gas-liquid mixing injection hole 12, the effect of attracting the atomized air 10a and the fuel spray 6 that have passed through the gas-liquid mixing injection hole 12 is increased. This attraction effect acts to increase the amount of atomized air 10a and to stretch the liquid film portion of the fuel spray 6 immediately after injection injected from the liquid fuel injection valve 9, thereby further atomizing the fuel spray 6. Will effectively promote.
[0048]
From the viewpoint of promoting atomization of the fuel spray 6, the length L of the guide 131 is preferably short, and the length L is preferably zero.
[0049]
Accordingly, by setting the length L of the guide 131 according to the purpose, it is possible to easily change the position where the fuel spray 6 reaches the heater 70 and the like, so that it is possible to easily cope with various engines. .
[0050]
The heater 70 is energized when the internal combustion engine 1 is started, and the energization is stopped when a predetermined time has elapsed after the start. Thereby, useless energization to the heater 70 is eliminated, and power consumption is reduced.
[0051]
In this embodiment, since the atomized air 10a collides with the fuel spray 6 to promote atomization of the fuel spray 6, heat transfer between the intake air and the fuel spray 6 is improved. Further, since the atomization of the fuel spray 6 is promoted, most of the fuel spray 6 can reach the combustion chamber 54 along the flow in the intake pipe without colliding with the heater 70. Accordingly, the burden on the heater 70 is reduced, and power consumption can be suppressed. That is, since the current supplied to the heater 70 can be reduced, the reliability and durability of the heater 70 and related parts can be improved.
[0052]
As described above, according to this embodiment, the fuel spray 6 injected into the air-fuel mixture generation chamber 140 is vaporized by efficiently promoting atomization and gas-liquid mixing. Can be efficiently supplied into the intake manifold 3. The fuel spray 6 supplied into the intake manifold 3 passes through the intake manifold 3, is supplied as intake air (mixture) 10 f into the intake pipe downstream thereof, and is supplied to each combustion chamber 54. The
[0053]
In the combustion chamber 54, the fuel spray 6 that has been atomized and vaporized is supplied, so that the ignition timing, that is, the ignition timing of the spark plug 53 is delayed (retarded) while maintaining the stability of combustion. It becomes possible to make it. As a result, high-temperature exhaust gas 26 that does not perform expansion work can be generated in the exhaust manifold 48, and early warm-up and early activation of the three-way catalytic converter 51 can be realized. Exhaust gas 26 that has reached exhaust manifold 48 is exhausted to the outside through a muffler muffler (not shown) after purifying harmful substances such as HC generated during combustion by activated three-way catalytic converter 51.
[0054]
The attachment position and shape of the heater 70 are not limited to those illustrated in this embodiment, and a lattice heater may be disposed downstream of the fuel spray 6. In this case, vaporization of not only coarse particles present in the fuel spray 6 but also atomized fuel spray 6 can be promoted. Further, a plate heater may be disposed on the arrival wall surface of the fuel spray 6. Further, by providing heaters 71a and 71b in the intake bypass pipes 5a and 5b and heating the atomized air 10a and the carrier air 10b passing through the intake bypass pipes 5a and 5b, atomization, gas-liquid mixing, and vaporization are performed. Can be promoted.
[0055]
In this embodiment, when the idling speed is controlled by opening / closing control of the throttle valve 4, the intake air is supplied in a steady state via the bypass pipes 5a and 5b without using the ISC valve 73. It is possible.
[0056]
When the upstream swirl type liquid fuel injection valve 9 is used, the injected fuel behaves so as to swirl and promote atomization. Therefore, the action of promoting atomization by the atomized air 10a may be small, and the amount of atomized air 10a can be reduced. Accordingly, the amount of the conveyance air 10b can be increased to increase the conveyance force for the fuel spray 6.
[0057]
In this embodiment, fuel atomization means (atomizer) is provided inside the liquid fuel injection valve 9, and the atomized air 10 a merges with the fuel spray 6 outside the liquid fuel injection valve 9. That is, it can be said that the atomized air 10a constitutes an external mixing type atomizer (apparatus). The outlet of the liquid fuel injection hole of the liquid fuel injection valve 9 corresponds to the outlet of the atomizer. The fuel spray 6 injected from the external mixing type atomizer (liquid fuel injection valve 9) is a surrounding passage wall, for example, gas-liquid mixing injection hole 12, inner peripheral surface 134 and outer peripheral surface 135 of the guide 131, fine particles. Atomization and gas-liquid mixing are promoted without being constrained by the inner wall surface 150 of the atomizer base member 102, the diaphragm 17 and the inner wall surface (inner peripheral surface) of the heater 70, and the like. That is, the atomization and gas-liquid mixing of the fuel spray 6 are promoted without contacting the surrounding passage walls.
[0058]
The external mixing type atomizer in this embodiment is configured by fitting the liquid fuel injection valve 9, the injection valve holder 120, and the gas-liquid mixing injection nozzle 130 concentrically with the atomizer base member 102. Can improve productivity.
[0059]
Liquid fuel injection valve 9, atomization gas passage 7, gas-liquid mixing injection hole 12, carrier gas passage 8, inner peripheral surface 134 and outer peripheral surface 135 of guide 131, inner wall surface 150 of atomizer base member 102, throttle 17 and The inner wall surface (inner circumferential surface) of the heater 70 is disposed on the coaxial line.
[0060]
As described above, the atomizing means of the liquid fuel injection valve 9 includes a fuel passage that gives a velocity component in the axial direction (the central axis direction or the injection direction of the liquid fuel injection hole) and the tangential direction to the fuel spray 6 to be injected. It is realized by.
[0061]
The position of the passage wall surface surrounding the fuel spray 6 downstream of the liquid fuel injection hole of the liquid fuel injection valve 9 and the injection angle of the fuel spray 6 are set so as to form an interval between the passage wall surface and the outer edge of the fuel spray 6. is doing. The passage wall surface includes, for example, a downstream portion of the gas-liquid mixing injection hole 12 in the gas-liquid mixing injection nozzle 130, an inner peripheral surface 134 of the guide 131, an inner wall surface 150 of the atomizer base member 102, an inner wall surface of the throttle 17, and a heater. 70 inner wall surfaces and the like.
[0062]
From another viewpoint, the passage cross section (diameter) of the fuel spray 6 from the outlet (downstream end) of the atomizing gas passage 7 to the outlet (downstream end) of the carrier gas passage 8 is the atomizing gas passage 7. That is, it is formed larger than the passage cross section (diameter) of the fuel spray 6 at the annular outlet opening. Alternatively, the passage cross section (diameter) of the fuel spray 6 from the outlet (downstream end) of the atomizing gas passage 7 to the outlet (downstream end) of the carrier gas passage 8 may be configured to increase toward the downstream side.
[0063]
Further, this state may be regarded as a state in which an air layer is formed outside the outer edge of the fuel spray 6. This air layer is a layer in which the spray concentration is much thinner than the inside of the edge regarded as the outer edge of the fuel spray 6. Note that due to the effects of the atomized air 10a and the carrier air 10b, the injection angle of the fuel spray 6 may be smaller than the injection angle of the fuel injection valve 9 alone or in part. Therefore, the effects of the atomized air 10a and the carrier air 10b should be taken into consideration for the setting of the injection angle, the above-described holes, and the respective inner wall surfaces.
[0064]
In this embodiment, as shown in FIG. 2, the carrier gas passage 8 is provided with a carrier gas swirling member 200 for turning the carrier air 10b. As shown in FIG. 3, the carrier gas swirling member 200 includes a cylindrical portion 201 formed in a cylindrical shape and a plurality of fins 202 formed integrally with the cylindrical portion 201. The fin 202 is formed at a height t from the inner peripheral surface 204 of the cylindrical portion 201 in the inner peripheral direction, and is formed in a spiral shape in the axial direction along the inner peripheral surface 204 of the cylindrical portion 201. In FIG. 3, the outer wall surface 135 of the guide 131 of the gas-liquid mixing injection nozzle 130 is in contact with the portion indicated by the broken line 206, and the shaft is defined by the outer wall surface 135 of the guide 131, the fins 202, A spiral carrier gas passage 203 is formed in the direction. The carrier gas swirling member 200 is fixed by bringing its outer peripheral surface 205 into contact with the inner wall surface 150 of the atomizer base member 102. The number of fins 202 may be one as long as a sufficient turning force can be applied to the carrier air 10b.
[0065]
The carrier air 10b that has flowed into the carrier gas passage 203 passes through the carrier gas passage 203 and is given a turning force. The carrier air 10b swirls to form a vortex. The fuel spray 6 is conveyed while being constrained by the carrier air 10b supplied into the mixture generation chamber 140 along the inner wall surface 150 of the atomizer base member 102 while swirling. It is possible to reduce the amount of adhesion to the throttle 17 and the intake pipe inner wall surface by concentrating on the center (center) portion.
[0066]
In this embodiment, as shown in FIG. 2, the atomization gas passage member 7 is provided in the atomization gas passage 7 for applying rotation to the atomization air 10 a. As shown in FIG. 4, the atomized gas swirling member 22 is disposed on the surface of the atomized gas passage 7 facing the tip surface 24 a of the liquid injection nozzle 24 of the liquid fuel injection valve 9. The end surface 24a and the end surface 221 of the atomized gas swirling member 22 are in contact with each other. A circular hole 23 through which the fuel spray 6 and the atomized air 10a pass passes through the center of the atomized gas swirling member 22. In addition, the surface 221 of the atomized gas swirling member 22 is provided with a plurality of grooves 251 from which the atomized air 10 a is directed to the hole 23 from the outer periphery of the atomized gas swirling member 22. The direction of these grooves 251 is formed so as to be oriented in the direction eccentric from the central axis of the hole 23. In this embodiment, four grooves 251 are formed. A swirling passage 25 is formed by bringing the tip end surface 24a of the liquid injection nozzle 24 of the liquid fuel injection valve 9 into contact with a part of the vicinity of the hole 23 of the groove 251, and the swirling atomized air 10a is supplied to the hole 23. Configure as you can. A circle indicated by a broken line in FIG. 4A indicates a positional relationship in which the atomized gas swirling member 22 and the tip end surface 24a of the liquid injection nozzle 24 of the fuel injection valve 9 are in contact with each other.
[0067]
The atomized air 10 a passes from the atomized gas passage 7 through the swirl passage 25 formed by the groove 251 of the atomized gas swirling member 22. Since the atomized air 10a collides (combines) with the fuel spray 6 so as to be eccentric and swirl, the action of promoting atomization and gas-liquid mixing of the fuel spray 6 can be enhanced.
[0068]
The upstream revolving liquid fuel injection valve 9 that injects fuel while swirling is injected so that the fuel spray 6 itself revolves. In order to increase the atomization of the fuel spray 6 swirling and the promotion of gas-liquid mixing in this way, the atomized gas is ejected so as to spout the atomized air 10a swirling in the direction opposite to the swirling direction of the fuel spray 6. By configuring the swirl passage 25 of the swirl member 22, the atomized air 10 a may collide with the fuel spray 6 while swirling in the direction opposite to the swirl direction of the fuel spray 6.
[0069]
As shown in FIG. 2, the carrier air 10b may be configured to be blown into the intake manifold 3 from the position and direction of the arrow 10b ′ or 10b ″. In order to introduce into the intake manifold 3, the intake bypass pipe 5b is connected to the side wall 3a of the intake manifold 3 from the direction crossing the passage wall surface of the intake pipe 5 toward the intake pipe 5. Also, the arrow 10b " Thus, in order to introduce the carrier air 10b into the intake manifold 3, the intake bypass pipe 5 b is connected to the surface 3 b of the intake manifold 3 facing the fuel spray 6 in the injection direction of the fuel spray 6. The carrier air 10b ′, 10b ″ does not necessarily have to be introduced perpendicularly or parallel to the surface 3a, 3b of the fuel spray 6 or the intake manifold 3; The intake bypass pipe 5b may be communicated with the intake manifold 3 so as to merge with the fuel spray 6 at an angle.
[0070]
The carrier air 10b ′, 10b ″ is opposed to the fuel spray 6 from the front or is supplied from a direction with a predetermined angle, whereby the fuel spray 6 and the carrier air 10b ′, 10b ″ are The relative velocity of the collision can be increased, and the carrier air 10b ′, 10b ″ can be actively used for atomization of the fuel spray 6 and promotion of gas-liquid mixing. Also, the carrier air 10b ′, 10b. ”Is supplied to the collective intake pipe 3, it is possible to reduce the fuel spray 6 from adhering to the wall surface of the collective intake pipe 3.
[0071]
Next, the relationship between the average particle diameter of the fuel spray 6 supplied from the fuel supply apparatus 100 to the internal combustion engine 1 and the amount of atomized air 10a will be described with reference to FIG.
[0072]
In the figure, the vertical axis indicates the average particle diameter of the fuel spray 6 and indicates the average particle diameter at a position 60 mm downstream from the liquid injection hole of the fuel injection valve 9 in the injection direction. The horizontal axis represents the gas-liquid volume flow rate ratio, which is the volume flow rate ratio between the amount of fuel atomized (Ql) injected from the fuel injection valve 9 and the amount (Qa) of atomized air 10a passing through the gas-liquid mixture injection holes 12. (Qa / Ql) is shown. In the figure, the solid line shows the relationship between the average particle diameter and the gas-liquid volume flow rate ratio (Qa / Ql) in the intake pipe pressure during idling operation of the internal combustion engine 1. Here, the amount of the atomized air 10a is controlled by changing the area of the gas-liquid mixed injection hole 12 through which the atomized air 10a passes when the pressure in the intake pipe is constant. Further, in the figure, the solid line indicates that the amount of atomized fuel injected from the fuel injection valve 9 is constant and only the amount of atomized air 10a is changed.
[0073]
The average particle size of the fuel spray 6 is increased by increasing the gas-liquid volume flow rate ratio, that is, by increasing the amount of atomized air 10a, and thereafter during a predetermined flow rate ratio (Qa / Ql = about 700 to 2000), The average particle size is about 10 μm, and if the flow rate ratio is increased further, the average particle size tends to increase. This tends to be caused by the flow rate and flow rate ratio between the fuel spray 6 and the atomized air 10a passing through the gas-liquid mixing injection hole 12 and the supply positional relationship between the fuel spray 6 and the atomized air 10a. .
[0074]
From this result, in this embodiment, the region where the average particle size is the smallest and the gas-liquid volume flow rate ratio indicated by a circle surrounded by a broken line as small as possible is 1000 is adopted. Thereby, the amount of atomized air 10a can be reduced while ensuring the average particle size of the fuel spray 6 to about 10 μm. Accordingly, since more carrier air 10b passing through the carrier gas passage 8 can be secured, the carrier ability for the fuel spray 6 can be improved, and therefore the amount of adhesion to the inner wall surface of the intake pipe can be reduced. it can.
[0075]
According to SAE 99010792 “An Internally Heated Tip Injector to Reduce HC Emissions During Cold-Start”, if the particle size of the fuel spray is about 20 μm, the fuel spray can be carried on the air flow in the intake pipe and conveyed to the combustion chamber. it can. In this embodiment, even if the flow rate ratio is about Qa / Ql = 250 to 2750, the average particle size is about 20 μm or less, and about 30 to 40% of the particle size is 20 μm or less in the fuel spray is burned. It can be conveyed to the chamber, and the amount of adhesion to the inner surface of the intake pipe can be sufficiently reduced. The fuel spray that does not ride on the airflow in the intake pipe passes through the heater 70 or collides with the heater 70 to further promote atomization and vaporization, thereby reducing adhesion to the inner wall surface of the intake pipe. .
[0076]
Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, an exhaust gas recirculation (EGR) gas is used as a carrier gas for gas-liquid mixing and transporting the atomized gas and atomized fuel spray for promoting atomization of the fuel spray. This is the configuration to use.
[0077]
In the second embodiment, the EGR gas 27 that is a part of the exhaust gas 26 discharged from the internal combustion engine 1 is supplied to the atomized gas passage 7 and the carrier gas passage 8 by the exhaust bypass pipe 30, and the atomized EGR gas is supplied. 27a and the transport EGR gas 27b. For this purpose, the inlet side (upstream end) of the exhaust bypass pipe 30 is communicated with the exhaust manifold 48, and the outlet side (downstream end) of the exhaust bypass pipe 30 is connected via the ISC valve 73 and the pressure regulation chamber 101. The atomized gas passage 7 and the carrier gas passage 8 are communicated with each other.
[0078]
Next, airflow will be described. The EGR gas 27a supplied from the exhaust manifold 48 to the atomization gas passage 102a and the carrier gas passage 102b of the atomizer base member 102 through the exhaust bypass pipe 30, the ISC valve 73, and the pressure regulating chamber 101 is added by the exhaust pressure. It will flow under pressure. That is, as the internal combustion engine 1 is operated, the intake manifold 47 side becomes negative pressure and the exhaust manifold 48 side becomes positive pressure, so the pressurized EGR gas 27 is supplied to both the gas passages 102a and 102b. It will be.
[0079]
Other configurations such as the atomization gas passage 7 and the carrier gas passage 8 are the same as those in the first embodiment described above, and therefore, the same reference numerals are assigned and redundant description is omitted.
[0080]
Since the EGR gas 27 is a gas immediately after exhaust, it has a higher temperature and pressure than the intake air sucked from the outside. The heat and pressure of the EGR gas 27 work effectively for promoting atomization and vaporization of the fuel spray 6 injected from the second liquid fuel injection valve 9.
[0081]
In this embodiment, the intake air 10 supplied to the internal combustion engine 1 is controlled by opening / closing control of the throttle valve 4. The upstream and downstream of the throttle valve 4 are connected by a bypass pipe, and an ISC valve is connected to the bypass pipe. It can also be realized by arranging and controlling.
[0082]
In this embodiment, the EGR gas 27 is supplied to the atomizing gas passage 7 and the carrier gas passage 8. However, the EGR gas 27 is supplied to the carrier gas passage 8 and a part of the intake air 10 is atomized. A piping configuration for supplying the gasified gas passage 7 or a piping configuration for supplying the EGR gas 27 to the atomized gas passage 7 and supplying a part of the intake air 10 to the carrier gas passage 8 may be used.
[0083]
According to this embodiment, atomization and vaporization of the fuel spray 6 can be promoted using the high-temperature, high-pressure EGR gas 27, and the burden on the heater 70 can be further reduced.
[0084]
Next, a third embodiment of the present invention will be described with reference to FIGS.
[0085]
FIG. 7 shows an electronically controlled throttle body 300 incorporating the throttle valve 4, an intake manifold 3 positioned upstream of the intake manifold 47, and a fuel supply device disposed between the intake passage 303 and the intake passage 303. 1 is an external perspective view showing the configuration of 100. FIG. 8 shows the electronic control throttle body 300, the intake passage 303, the intake manifold 3, and the intake manifold 47 in FIG. 7 that are substantially centered along the intake passage 5 and are disposed in the electronic control throttle valve body 300. It is sectional drawing cut | disconnected along the surface perpendicular | vertical with respect to the throttle valve shaft 4a.
[0086]
The intake manifold 47 includes a fuel injection valve mounting portion 2a for installing the first liquid fuel injection valve 2 for each cylinder.
[0087]
The intake passage 5 in the electronically controlled throttle body 300 and the intake manifold 3 are communicated by an intake passage 304 in the intake passage portion 303. Further, the fuel supply device 100 is connected to the intake passage 304 of the intake passage portion 303, and the air-fuel mixture 10e generated by the fuel spray injected from the second liquid fuel injection valve 9 installed in the fuel supply device 100 is obtained. Communication is performed so as to supply the air into the intake passage 304 in the intake passage portion 303. The air-fuel mixture 10e supplied to the intake passage 304 flows into the intake manifold 3 downstream thereof, and then passes through the intake manifold 47 to be efficiently supplied as the air-fuel mixture 10f (intake air and fuel) into each combustion chamber. Is done.
[0088]
In the third embodiment, the injection direction of the fuel spray injected from the fuel injection valve 9 in the fuel supply device 100 is substantially the same as the axial flow direction of the intake passage 5 in the electronically controlled throttle body 300. Although the configuration is a right angle, the axial flow direction of the intake passage 5 and the injection direction of the fuel spray injected from the liquid fuel injection valve 9 in the fuel supply device 100 may be the same.
[0089]
The electronically controlled throttle body 300 includes a throttle valve 4 for controlling a desired intake air amount in accordance with the operating state of the internal combustion engine 1. That is, the intake air amount is controlled by the opening of the throttle valve 4. Further, a drive motor 301 for controlling the opening degree by driving the throttle valve 4, a drive mechanism for transmitting the power of the drive motor 301 into the cover 302 with a built-in throttle valve drive mechanism, and the throttle valve 4 A throttle positioning sensor 52 for detecting the opening is incorporated.
[0090]
The intake bypass pipe 5c of the fuel supply device 100 is communicated with the intake passage 5 upstream of the throttle valve 4 in the electronically controlled throttle body 300 through a bypass passage (not shown), and part of the intake air 10 is taken into the intake bypass. It is the structure supplied to the pipe | tube 5c.
[0091]
In the bypass pipe that connects the intake passage 5 upstream of the throttle valve 4 and the intake bypass pipe 5c, when the air flow rate is controlled precisely or when air is not supplied to the intake bypass pipe 5c. It is preferable to provide an air control valve for controlling the air flow rate.
[0092]
FIG. 9 is a longitudinal side view of the atomizing device portion of the fuel supply device 100 shown in FIGS. 7 and 8 cut along the injection direction of the fuel spray 6 injected from the liquid fuel injection valve 9.
[0093]
The intake bypass pipe 5c communicates with a pressure regulating chamber 101d formed in the atomizer base member 102d. The pressure regulating chamber 101d communicates with the inner wall surface 150b of the atomizer base member 102d, and the carrier gas passage 8 is an annular gap formed between a part of the inner wall surface 150b and the outer wall surface of the gas-liquid mixing nozzle 130b. Communicate with. The carrier gas passage 8 communicates with the mixture generation chamber 140 downstream of the atomizer base member 102d via the carrier gas metering unit 8a.
[0094]
Further, the side wall surface of the gas-liquid mixing / injecting nozzle 130 b has at least one or more nozzle passages 103 that are openings, and the inner and outer wall surfaces of the gas-liquid mixing / injecting nozzle 130 b are communicated with each other through the nozzle passage 103. The atomized gas passage 7 that is an annular gap is formed by the inner wall surface of the gas-liquid mixing injection nozzle 130b, the outer peripheral portion of the liquid fuel injection valve 9, and the front end surface of the liquid injection nozzle. The atomizing gas passage 7 communicates with a gas-liquid mixing injection hole 12 located downstream in the injection direction of the liquid fuel injection valve 9, and this gas-liquid mixing injection hole 12 is an air-fuel mixture downstream of the atomizing device base member 102c. Open to the generation chamber 140.
[0095]
The downstream side of the air-fuel mixture generation chamber 140 communicates with the intake passage 304 in the intake passage portion 303 on the downstream side of the throttle valve 4.
[0096]
A plurality of plate-shaped heaters (PTC heaters) are disposed in the heater portion 72 that is disposed on the downstream side of the atomizer base member 102c of the fuel supply device 100 and constitutes a part of the outer peripheral wall of the mixture generation chamber 140. ) 70a is disposed in a cylindrical shape so as to surround the outer edge of the fuel spray 6 along the inner wall surface. In addition, a plate-like heater 70b is disposed at a predetermined angle with respect to the injection axis direction of the fuel spray 6 in the downstream portion of the air-fuel mixture generation chamber 140, thereby efficiently vaporizing the fuel spray 6 The air-fuel mixture 10e is generated and guided into the intake passage 304 downstream of the throttle valve 4.
[0097]
In such a fuel supply device 100, the intake air 10d that is diverted from the intake air 10 upstream of the throttle valve 4 flows into the intake bypass pipe 5c through the bypass pipe (not shown), and flows into the pressure regulating chamber 101d. . Then, a part of the intake air 10d flowing into the pressure regulating chamber 101d is transferred to the transfer gas passage 8 constituted by a part of the inner wall surface 150b of the atomizer base member 102d and the outer wall surface of the gas-liquid mixing injection nozzle 130b. The fuel spray 6 injected from the liquid fuel injection valve 9 is supplied into the air-fuel mixture generation chamber 140 so as to wrap.
[0098]
On the other hand, the remainder of the intake air 10d that has flowed into the pressure regulating chamber 101d is atomized air 10a into the atomized gas passage 8 constituted by the inner wall surface of the gas-liquid mixing injection nozzle 130b, the outer peripheral portion and the tip of the liquid fuel injection valve 9. And the fuel spray 6 injected from the liquid fuel injection valve 9 is supplied (impacted) more efficiently than the entire circumference, and then passed through the gas-liquid mixing injection hole 12 and positioned downstream thereof. The mixture is supplied into the gas mixture generation chamber 140.
[0099]
With these configurations, the atomized air 10a and the carrier air 10b, the fuel spray 6 injected from the fuel injection valve 9 promotes atomization efficiently and is conveyed. Further, since the heater 70a is located in a cylindrical shape along the outer edge of the fuel spray 6 when passing through the air-fuel mixture generation chamber 140, the coarse particles outside the fuel spray 6 are efficiently atomized and vaporized. At the same time, droplets containing coarse particles that are difficult to atomize and transport by the atomized air 10a and the carrier air 10b can collide with the heater 70a to promote vaporization. Further, the heater 70 b disposed at a predetermined angle in the injection direction of the fuel spray 6 injected from the fuel injection valve 9 can change the traveling direction of the fuel spray 6, and the air-fuel mixture generated by the fuel spray 6. 10e can be efficiently supplied into the intake passage 304 on the downstream side of the throttle valve 4. Therefore, the air can be efficiently transferred to the intake manifold 47 and further to the respective combustion chambers (not shown) through the intake manifold 3 on the downstream side.
[0100]
Next, effects common to the above-described embodiments will be described with reference to FIG.
[0101]
In FIG. 10, (a) shows the ignition timing on the vertical axis and the particle size of the fuel spray supplied from the fuel supply device 100 on the horizontal axis. (B) shows the catalyst temperature on the vertical axis and the time on the horizontal axis. In the figure, the thin line represents the relationship between the catalyst temperature and the time when the internal combustion engine ignition timing is normal, and the thick line represents the retarded internal combustion engine ignition timing. It shows the relationship between catalyst temperature and time. (C) shows the total HC emission amount on the vertical axis, and the time on the horizontal axis. In the figure, the thin line represents the relationship between the HC total emission amount and time when the internal combustion engine ignition timing is normal, and the thick line represents the internal combustion engine. Represents the relationship between the total HC emission amount and time when the ignition timing of the retard is retarded.
[0102]
The entire circumference of the fuel spray 6 in which the intake air 10a or the EGR gas 27 is controlled by controlling the ISC valve 73 at a low temperature or normal temperature start, and a part of the atomized air 10a and the atomized EGR gas 27a is injected from the fuel injection valve 9 By causing the fuel sprays 6 to collide with each other, the atomization of the fuel spray 6 and the promotion of gas-liquid mixing are promoted, and then the fuel spray 6 is transported in order to suppress the adhesion of the fuel spray 6 to the inner surface of the intake pipe. By forming the flow of the carrier air 10b or the carrier EGR gas 27b and providing the heater 70 downstream thereof, atomization, gasification and vaporization are promoted, and the amount of adhesion to the wall surface can be reduced. it can.
[0103]
This is because the atomization of the fuel spray 6 can increase the surface area per mass of the fuel so that vaporization can be accelerated, and the followability to the air flow in the intake manifold 47 can be improved, and the atomized fuel can be improved. This is because the amount of fuel adhering to the inner wall surface of the intake pipe is reduced by forming the flow for transporting the spray 6. By reducing the amount of wall surface adhesion, the exhaust purification can be improved as well as the startability and fuel consumption of the internal combustion engine 1 can be improved.
[0104]
Further, by promoting atomization, gas-liquid mixing and vaporization of the fuel spray 6 supplied to the internal combustion engine 1, as shown in FIG. 10A, the ignition of the internal combustion engine 1 while maintaining the stability of combustion. The time can be delayed.
[0105]
By delaying (retarding) the ignition timing more than usual, high-temperature exhaust gas that does not perform expansion work can be generated, and as shown in FIG. 10B, the temperature of the catalyst of the three-way catalytic converter 51 is increased early. Can be heated to high temperatures. In the figure, the dotted line on the horizontal axis indicates the catalyst activation temperature, and it is possible to reach the catalyst activation temperature in a short time by increasing the catalyst temperature at an early stage.
[0106]
Due to the early activation of the catalyst of the three-way catalytic converter 51, as shown in the graph of FIG. 10 (c), the total HC emission amount is markedly reduced when the internal combustion engine 1 is started as compared with the case where the ignition timing is normal. can do. Note that not only HC but also NOx and CO can be reduced by the early warm-up of the three-way catalytic converter 51.
[0107]
As described above, by promoting atomization, gas-liquid mixing and vaporization of the fuel spray 6 injected from the fuel injection valve 9, the amount of adhesion to the inner wall surface of the intake pipe is reduced, and the internal combustion engine 1 can be started at low temperatures and at normal temperatures. Improvements in fuel consumption, fuel consumption, and exhaust purification can be realized.
[0108]
In each of the above-described embodiments, the configuration using the heater 70 has been described. However, if the atomization, gas-liquid mixing, and vaporization by the atomized gas and the carrier gas are sufficient, the heater 70 may be omitted. It is possible to implement.
[0109]
In each of the above-described embodiments, a so-called port injection engine in which the first liquid fuel injection valve 2 for injecting fuel into each cylinder is provided in the intake manifold 47 has been described as an example. The same effect can be obtained even when applied to a so-called in-cylinder injection engine that directly injects.
[0110]
【The invention's effect】
According to the present invention, The carrier air guided to the guide and supplied to the outside of the downstream part of the fuel spray conveys the fuel spray injected from the liquid fuel injection valve downstream from the outer periphery, thereby conveying the fuel spray downstream. Since atomization of fuel spray and gas-liquid mixing can be promoted to reduce the amount of wall surface adhesion, not only the startability and fuel consumption of the internal combustion engine can be improved, but also exhaust purification can be improved. In addition, since the heater is used in an auxiliary manner, the burden on the heater is reduced, electric energy consumed by the heater can be reduced, and in some cases, the heater can be made unnecessary. Further, by reducing the electric energy consumed by the heater, the reliability and durability of the heater can be improved.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a first embodiment of an internal combustion engine equipped with a fuel supply device of the present invention.
2 is an enlarged vertical side view of the fuel supply device shown in FIG. 1. FIG.
3 is a view (b) of the carrier gas swirling member in the fuel supply apparatus shown in FIG. 2 as viewed from the air flow direction, and a cross-sectional view taken along the line AA in (b).
4 is a diagram (a) viewed from the fuel injection direction of the atomized gas swirl member in the fuel supply device shown in FIG. 2, and a cross-sectional view taken along line AA in (a).
FIG. 5 is a diagram showing the relationship between the gas-liquid volume flow rate ratio and the average particle diameter of fuel spray when the pressure in the intake pipe is kept constant.
FIG. 6 is a schematic diagram showing a second embodiment of an internal combustion engine equipped with the fuel supply device of the present invention.
FIG. 7 is an external perspective view showing a third embodiment of an internal combustion engine equipped with the fuel supply device of the present invention.
8 is a longitudinal sectional view of the fuel supply device shown in FIG.
9 is a longitudinal side view of a part of the atomization device in the fuel supply device shown in FIG. 7. FIG.
FIG. 10 is a diagram for explaining the influence of atomization of fuel spray on exhaust purification.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... 1st liquid fuel injection valve, 3 ... Intake collecting pipe, 4 ... Throttle valve, 5 ... Intake pipe, 5a, 5b ... Intake bypass pipe, 6 ... Fuel spray, 7 ... Atomization gas passage , 8 ... carrier gas passage, 9 ... second liquid fuel injection valve, 10 ... intake air, 10a ... atomized air, 10b ... carrier air, 11 ... air flow sensor, 12 ... gas-liquid mixing injection hole, 17 ... throttle, 22 ... atomizing gas swirling member, 23 ... hole, 24 ... liquid injection nozzle, 24a ... tip surface, 25 ... swirling passage, 26 ... exhaust, 27 ... EGR gas, 27a ... atomized EGR gas, 27b ... transport EGR gas, 30 ... Bypass pipe, 40 ... Fuel tank, 41 ... Fuel, 42 ... Fuel pump, 43 ... Filter, 44 ... Intake valve, 45 ... Pressure regulator, 46 ... Air cleaner, 47 ... Intake manifold, 48 ... Exhaust manifold 50 ... oxygen concentration sensor, 51 ... three-way catalytic converter, 52 ... throttle sensor, 53 ... spark plug, 54 ... combustion chamber, 55 ... intake hole, 56 ... water temperature sensor, 57 ... ECU, 58 ... exhaust valve, 59 ... Exhaust hole, 70, 70a, 70b ... Heater, 73 ... ISC valve, 100 ... Fuel supply device, 101a, 101b ... Pressure regulation chamber, 102 ... Atomizer base member, 102a ... Atomizer gas passage, 102b ... Carrier gas Passage, 102c ... Fuel injection valve fitting hole, 103 ... Nozzle passage, 120 ... Injection valve holder, 121, 132, 135 ... Outer wall surface, 130 ... Gas-liquid mixed injection nozzle, 131 ... Guide, 133, 134, 150 ... Inside Wall surface, 140 ... mixture generation chamber, 200 ... carrier gas swiveling member, 201 ... cylindrical portion, 202 ... fin, 203 ... carrier gas passage, 204 ... inner peripheral surface, 205 The outer circumferential surface, 221 ... surface, 251 ... groove.

Claims (10)

A fuel supply comprising a fuel atomization device for atomizing a fuel spray injected from a liquid fuel injection valve by applying gas to the fuel spray, and supplying the atomized fuel spray downstream of the throttle valve in an intake pipe having a throttle valve In the device
The fuel atomization device is configured to inject first atomized gas that opens around the liquid fuel injection hole of the fuel injection valve and acts on the fuel spray injected from the liquid fuel injection hole to promote atomization. A gas passage, a second gas passage for injecting a carrier gas into the fuel spray so as to surround the fuel spray whose atomization is promoted by the atomized gas, and generating an air-fuel mixture; It is equipped with a heater installed so as to be located around the transport path ,
The second gas passage has an annular opening that faces the injection direction of the fuel spray around a central axis that passes through the center of the liquid fuel injection hole of the fuel injection valve and is hypothesized in the fuel injection direction. A fuel supply device comprising a gas passage formed outside a cylindrical guide extending downstream so as to cover the outer periphery of the fuel spray so as to be formed outside the portion .   2. The fuel supply apparatus according to claim 1, wherein an average particle size of the fuel spray is 20 [mu] m or less.   2. The fuel supply device according to claim 1, wherein the fuel atomization device has a ratio Qa / Ql of 250 to 2750, which is a ratio of the amount Ql of injected fuel and the amount Qa of atomized gas.   4. The fuel supply device according to claim 1, wherein the liquid fuel injection valve in the fuel atomization device includes a fuel passage for imparting axial and tangential velocity components to the fuel to be injected. .   5. The fuel supply device according to claim 4, wherein the first gas passage is formed with a tip end surface of the fuel injection valve as a part of a passage wall. 6. The liquid fuel injection hole according to claim 1, wherein the first gas passage opens annularly around a central axis that passes through the center of the liquid fuel injection hole of the fuel injection valve and is hypothesized in the fuel injection direction. the fuel supply system, characterized in that the gas passage flowing gas in a direction transverse to said central axis toward the.   7. The fuel supply apparatus according to claim 1, wherein the flow rate of the carrier gas flowing through the second gas passage is greater than the flow rate of the atomized gas flowing through the first gas passage.   8. The first gas passage and the second gas passage according to claim 1, wherein the first gas passage and the second gas passage are configured in common as one gas passage whose upstream end is branched from the intake pipe on the upstream side of the throttle valve. And a fuel supply device that is branched into two passages on the downstream side.   8. The method according to claim 1, wherein an upstream end of at least one of the first gas passage and the second gas passage is connected to an exhaust pipe of an internal combustion engine. Fuel supply device.   An internal combustion engine comprising the fuel supply device according to claim 1.

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