JP4178889B2 - Intake control device for fuel injection engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an intake control device for an engine, and more particularly to an intake control device for a fuel injection engine having a throttle valve.
[0002]
[Prior art]
A conventional fuel injection device of a fuel injection type engine has a plurality of injectors disposed in a fuel intake passage (for example, a throttle body). For example, a fuel injection device injects fuel with a throttle valve almost fully open. One injector is disposed closer to the throttle valve, and a second injector is disposed downstream of the first injector to inject fuel with a small throttle valve opening (see, for example, Patent Document 1). The injector is arranged on the upstream side of the rotation center of the throttle valve so that the fuel injection direction collides with the upstream side of the throttle valve when fully opened, and the downstream side of the air-fuel mixture flow path is perpendicular to the one surface of the throttle valve. (For example, refer to Patent Document 2).
[0003]
The fuel injection device of the above-described example is equipped with two injectors in one throttle body, so that an optimum fuel supply is performed by a plurality of injectors according to the engine speed.
[0004]
As another configuration of the fuel injection device, a flow rate adjustment valve that is driven to open and close by a stepping motor is arranged upstream of the throttle valve to change the intake passage area, and the step motor is supplied to the intake flow rate by an external drive mechanism control means. Is controlled so that the increase speed of the engine becomes slower than the increase speed of the intake flow rate according to the opening speed of the throttle valve (see, for example, Patent Document 3), or an air valve is provided upstream of the throttle valve, The fuel injection direction is aligned with the upstream side of the throttle valve in the fully open position (see, for example, Patent Document 4), and two throttle valves are provided in the intake passage, and the downstream throttle valve In some cases, an injector is disposed at a position closer to the upstream side than (see, for example, Patent Document 5).
[0005]
The fuel injection devices disclosed in Patent Documents 3 to 5 described above are provided with a plurality of throttle valves, flow rate adjusting valves, and air valves in the throttle body, thereby adjusting the intake flow rate to alleviate the delay in fuel response. ing.
[0006]
[Patent Document 1]
JP-A-6-117314 (page 2-3, FIG. 1)
[Patent Document 2]
JP 7-139453 A (page 3-4, FIG. 1)
[Patent Document 3]
Japanese Patent Laid-Open No. 11-241636 (page 2-7, FIG. 2)
[Patent Document 4]
JP 62-38873 A (page 4-8, FIG. 1)
[Patent Document 5]
Japanese Utility Model Publication No. 3-116743 (page 5-9, FIG. 2)
[0007]
[Problems to be solved by the invention]
However, in the arrangement of the injectors of the fuel injection device as disclosed in Patent Documents 1 and 2, the injection state of the upstream injector on the high speed side is not significantly different from the injector on the low speed side, and in order to improve the combustion efficiency Furthermore, there is a problem that it is necessary to improve atomization and atomization of fuel.
[0008]
In addition, the configuration of the fuel injection device as disclosed in Patent Documents 3 to 5 controls the air that is sucked in, and does not control the injected fuel. It did not improve the condition of the fuel that was made.
[0009]
The present invention has been made in view of the above-described conventional problems, and reduces the deviation of the air-fuel mixture concentration and improves the atomization / homogenization of the injected fuel to improve the engine output and the exhaust purification. Thus, it is an object of the present invention to provide an intake control device for a fuel injection type engine that achieves both transient response of the engine and improved output.
[0010]
[Means for Solving the Problems]
The present invention provides a high rotation region injector and a low rotation region injector as fuel injection units for injecting fuel supplied from a fuel pump into an intake passage, and a flow rate adjusting unit for controlling the intake flow rate of the intake passage. In an intake control device for a fuel injection engine having a main throttle valve and a sub-throttle valve in a throttle body,
The sub-throttle valve is disposed on the intake upstream side of the main throttle valve that opens and closes in conjunction with the operation of the throttle grip, and is opened and closed by a motor drive in accordance with the operating state of the engine.
The low rotation region injector is disposed so that the intake port is located on the downstream side of the intake of the rotation axis of the main throttle valve and on the extension of the fuel injection angle range,
The high rotation region injector is substantially perpendicular to the intake passage on the side of the throttle body opposite to the low rotation region injector across the rotation shaft of the sub throttle valve, and is directed to the sub throttle valve rotation shaft. The fuel is injected so that the fuel directly collides with the surface of the sub-throttle valve located on the intake downstream side and the sub-throttle valve rotation shaft .
[0011]
According to this configuration, the upstream side of the injector and the high rotation region injector of the engine, since the downstream side of the injector and the low rotation region injector, be made compatible with improving improving the engine output transient response it can.
According to the injector for the high rotation region on the upstream side , the path to the combustion chamber is long and the mixing time can be made relatively long, so that the injected fuel collides with the throttle valve and is pulverized to improve atomization and make it even more uniform. As a result, combustion efficiency is improved, and engine output and exhaust purification (reduction of HC) can be achieved.
[0012]
According to the low-speed region injector on the downstream side , since the path to the combustion chamber is short and the arrival time of the fuel is short, the transient response is good.
Further, by disposing the upstream high rotation region injector and the downstream low rotation region injector at opposite positions (opposite sides), the deviation of the mixture concentration can be reduced.
[0014]
Further, the high-speed region for the injector, the sub-throttle valve rotating shaft while the opposite side of the substantially orthogonal to the intake passage in the throttle body side across the rotation shaft and the low speed region injector of the sub-throttle valve is arranged to direct, since the fuel injection such that fuel directly impinges on the surface and the sub-throttle valve rotating shaft located on the intake downstream side of the sub-throttle valve, fuel injected sub throttle valve body and the sub By colliding with the throttle valve rotation shaft , fine fuel droplets having a large injection amount (injection time is long) collide with each other, so that the miniaturization is promoted and the atomization of the fuel can be promoted.
[0015]
In particular, when the main throttle valve is rapidly opened to the full opening in the low engine speed range, more ideal air-fuel mixture can be supplied by promoting atomization, and transient response and engine output can be improved.
[0016]
Further, the present invention is such that the throttle body is tilted with respect to the cylinder axial direction of the engine and connected to the cylinder head, an air cleaner is disposed above the throttle body and the cylinder head, and the throttle body and the cylinder head are disposed below the air cleaner. It is preferable that the downstream injector is accommodated in a V-shaped space formed between the upstream injector and the upstream injector at a position facing the downstream injector on the opposite side of the V-shaped space across the throttle body. .
[0017]
According to this configuration, by storing the downstream injector toward the combustion chamber in a narrow space, a space for storing the upstream injector can be created.
Further, by arranging the upstream injector close to the air cleaner, a space is created around the engine wall surface (cylinder head, cylinder block, crankcase) below the air cleaner, and other equipment can be mounted.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 to 4 show an example of an embodiment of the present invention, and FIG. 1 shows an overall configuration of a motorcycle equipped with an engine employing an intake control device for a fuel injection engine according to an embodiment of the present invention. 2 is a partial side view showing the configuration of the engine in which the intake control device is incorporated, FIG. 3 is an explanatory view showing the operation of the intake control device when the throttle valve is in an idle state, and FIG. It is explanatory drawing which shows the operation | movement when the throttle valve is fully opened in the said intake control device.
[0019]
In the present embodiment, as shown in FIG. 1, an intake control device 100 according to the present invention is adopted in an engine 30 mounted on a motorcycle 1.
In the motorcycle 1, a front fork 4 that pivotally supports the front wheel 3 is provided on the front head of the body frame 2 by a handle bar 5 so as to be able to turn left and right. A swing arm 9 extending rearward and pivotally supporting the rear wheel 8 is supported on the pivot shaft 7 so as to be pivotable up and down. The swing arm 9 is a suspension mechanism (not shown) provided at the base end thereof. ) Is buffered and suspended.
[0020]
The vehicle body frame 2 has a pair of left and right main frames 2b extending in a vehicle body longitudinal direction rearward and downward from the head pipe 2a, and the main frame 2b is disposed at a lower front portion of the vehicle body frame 2. The engine 30 is suspended so that the cylinder head 31 is disposed therebetween. The power of the engine 30 is transmitted to the rear wheel 8 by the chain 11.
[0021]
The engine 30 includes a water temperature sensor (not shown) that detects the cooling water temperature of the engine, and an electronic control device (not shown) that inputs a detection value from the water temperature sensor and controls the opening and closing of a sub-throttle valve 52 described later. The intake control device 100 is provided.
The electronic control unit is configured to fully open the sub-throttle valve 52 for a certain period of time when the water temperature input when starting the engine is lower than a set value.
[0022]
An air cleaner 12 is disposed on the engine 30. A fuel pump 16 is disposed behind the air cleaner 12. An exhaust pipe 13 is connected to the front portion of the engine 30 and extends downward from the lower side of the engine 30 toward the lower side of the engine 30. Further, the exhaust pipe 13 extends from the lower side of the engine 30 to the right side in the vehicle body width direction. The exhaust muffler 14 is connected adjacent to the rear wheel 8.
[0023]
Further, the front side of the vehicle body frame 2 is directed from the front side to the rear side so as to cover the meters and electrical components disposed in front of the handlebar 5 and to cover the sides and lower sides of the engine 30 and peripheral parts. A cowling 20 is formed integrally with the vehicle body frame 2. The front cowling 20 is a molded product of synthetic resin.
[0024]
A radiator 17 is provided in front of the engine 30, and the radiator 17 is connected to a cooling water pump 18 provided on a side portion of the engine 30 via a cooling water hose 19. A fuel tank 21 is installed on the upper part of the engine 30, and a seating seat 22 is detachably mounted on the rear part of the fuel tank 21. The lower part and the periphery of the rear part of the seating seat 22 are covered with a rear frame cover 23. The rear frame cover 23 is a molded product of synthetic resin.
[0025]
The engine 30 is a four-cylinder, four-cycle fuel injection engine. As shown in FIG. 2, a piston 33 is provided in a cylinder block 32 so as to be able to reciprocate, and the piston 33 is connected via a connecting rod 34. It is connected to a crankshaft 35 that is an output shaft of the engine 30. The reciprocating movement of the piston 33 is converted into rotation of the crankshaft 35 by the connecting rod 34. A cylinder head 31 is provided at the upper end of the cylinder block 32.
[0026]
A combustion chamber 36 is provided between the cylinder head 31 and the piston 33, and an intake port 37 and an exhaust port 38 communicating with the combustion chamber 36 are provided in the cylinder head 31. The intake port 37 and the exhaust port 38 are provided with an intake valve 39 and an exhaust valve 40, respectively.
[0027]
An intake camshaft 41 and an exhaust camshaft 42 for opening and closing the intake valve 39 and the exhaust valve 40 are rotatably supported on the cylinder head 31. The intake camshaft 41 and the exhaust camshaft 42 are connected to the crankshaft 35 via a timing belt (not shown), and the rotation of the crankshaft 35 is transmitted to the intake camshaft 41 and the exhaust camshaft 42 by the timing belt. It has become so. When the intake camshaft 41 rotates, the intake valve 39 is driven to open and close, and the intake port 37 and the combustion chamber 36 are communicated / blocked. When the exhaust camshaft 42 rotates, the exhaust valve 40 is driven to open and close, and the exhaust port 38 and the combustion chamber 36 are communicated / blocked.
[0028]
An intake manifold 45 and an exhaust manifold 46 are connected to the intake port 37 and the exhaust port 38, respectively. An intake passage 47 is formed in the intake manifold 45 and the intake port 37, and an exhaust passage 48 is formed in the exhaust manifold 46 and the exhaust port 38. The intake passage 47 is provided to the rear of the engine 30, and the exhaust passage 48 is provided to the front of the engine 30. A throttle body 50 constituting the intake air control device 100 is disposed upstream of the intake manifold 45.
[0029]
The throttle body 50 is connected to the cylinder head 31 while being inclined with respect to the axial direction of the cylinder block 32. An air cleaner 12 is disposed above the throttle body 50 and the cylinder head 31, and a V-shaped space 12 a is formed below the air cleaner 12 between the throttle body 50 and the cylinder head 31.
[0030]
Further, as shown in FIGS. 3 and 4, the throttle body 50 is a sub-throttle that opens and closes as an intake flow rate adjusting means by motor driving (not shown) upstream of the intake passage in accordance with the operating condition of the engine. A valve 52 is disposed, and a main throttle valve 51 that opens and closes in conjunction with the operation of the throttle grip 70 is disposed on the downstream side, and an upstream injector 53a and a downstream side serve as fuel injection means for injecting fuel. An injector 53b is provided.
[0031]
The sub-throttle valve 52 includes a rotating shaft 52s orthogonal to the intake passage, and is disposed upstream of the throttle body 50 in the air flow direction.
The main throttle valve 51 includes a rotating shaft 51 s that is orthogonal to the intake passage, and is disposed in parallel to the sub-throttle valve 52 on the downstream side in the air flow direction from the sub-throttle valve 52.
[0032]
The upstream injector 53a is disposed at a position facing the rotation shaft 52s of the sub-throttle valve 52 and orthogonal to the intake passage, and the downstream injector 53b is offset downstream from the upstream injector 53a. It is arranged at the position.
[0033]
Further, the downstream injector 53b is inclined by 20 ° to 40 ° facing the intake port 37 of the cylinder head 31 toward the combustion chamber side at a position opposite to the upstream injector 53a across the main throttle valve 51. The intake port 37 is positioned on the extension of the injection angle range of the downstream injector 53b.
[0034]
In appearance, as shown in FIG. 2, the downstream injector 53b is disposed so as to be housed in a V-shaped space 12a formed between the throttle body 50 and the cylinder head 31 below the air cleaner 12. The upstream injector 53a is arranged at a position opposite to the V-shaped space 12a across the throttle body 50 and facing the downstream injector 53b.
[0035]
Next, the operation of the intake control device for the fuel injection engine according to this embodiment will be described.
First, when the engine is idling or in a low load state, as shown in FIG. 3, the main throttle valve 51 is substantially fully closed, and is disposed substantially horizontally in the drawing. At this time, the sub-throttle valve 52 is opened by a predetermined amount.
[0036]
The downstream injector 53b controls the injection amount without being affected by the main throttle valve 51 and the sub-throttle valve 52. For example, even when the valve opening of the main throttle valve 51 is small, an appropriate empty The fuel ratio can be obtained.
[0037]
When the valve opening of the main throttle valve 51 is increased to some extent, atomization is promoted by the fuel injection by the sub-throttle valve 52 and the upstream injector 53a, and the intake is performed well without being obstructed by the main throttle valve 51. Can do.
[0038]
Further, the fuel injected from the downstream injector 53b can be directly injected into the combustion chamber 36 within the injection angle range because the downstream injector 53b is arranged facing the intake port 37. Become.
[0039]
Next, when the engine is in a high speed / high load state, for example, when the throttle is fully opened, as shown in FIG. 4, the main throttle valve 51 and the sub throttle valve 52 rotate approximately 90 degrees and are arranged substantially parallel to the intake flow direction. It is installed and is fully open.
[0040]
The upstream injector 53a faces the sub-throttle valve 52 substantially vertically, and is mounted so that the axis of the injector 53a and the injection shaft are directed upward from the horizontal when mounted on the vehicle, generally along the bottom surface of the air cleaner 12. .
Fuel injected from the upstream side injector 53a, the sub-throttle valve 52 clash fine splash each other fuel further impinges on the body and the pivot shaft 52s, is promoted miniaturization, atomization of fuel is promoted In addition, the air-fuel mixture can be made uniform.
[0041]
As shown in FIG. 4, the fuel injected from the upstream injector 53a burns in a long path through the upstream injector 53a side separated by the sub throttle valve 52 and the main throttle valve 51 in the intake passage. It is supplied to the chamber 36.
[0042]
On the other hand, since the downstream injector 53b is disposed toward the intake port 37, fuel injection can be performed without being influenced by the main throttle valve 51 main body and the rotating shaft 51s.
[0043]
The fuel injected from the downstream injector 53b is separated by the sub-throttle valve 52 and the main throttle valve 51 in the intake passage, and is injected in a state inclined to the downstream injector 53b side into which fresh air flows. Furthermore, it becomes possible to inject directly into the combustion chamber 36 within the injection angle range.
[0044]
In this way, by arranging the upstream injector 53a and the downstream injector 53b at positions facing each other across the two throttle valves, the fuel is injected without being biased. Uniformity can be promoted.
[0045]
With the above-described configuration, according to the intake control device 100 of this embodiment, one throttle body 50 is provided with two throttle valves, that is, the sub throttle valve 52 on the upstream side and the main throttle valve 51 on the downstream side. In addition, since the two upstream injectors 53a and the downstream injectors 53b are disposed, and the directions of the two injectors are disposed as described above, the control of the intake air and the atomization of the injected fuel are performed. Promotion can be realized at the same time.
[0046]
Thereby, the combustion of fuel is improved, the engine output is improved, and HC can be reduced.
[0047]
Further, according to the present embodiment, since the upstream injector 53a is disposed orthogonal to the sub-throttle valve 52, when the injection amount is large (injection time is long), the injected fuel collides with the sub-throttle valve 52. Further, the fine fuel droplets collide with each other and the miniaturization is promoted, and the atomization of the fuel can be promoted.
[0048]
Further, according to the present embodiment, since the upstream injector 53a is disposed opposite to the sub throttle valve 52 on the upstream side of the intake passage of the throttle body 50, the path to the combustion chamber 36 is long and the mixing time is relatively long. Because it can be taken longer, the injected fuel collides with the throttle valve and is pulverized, resulting in improved atomization and further uniformization, improving combustion efficiency, improving engine output and purifying exhaust (reducing HC). Can be planned.
[0049]
Further, according to the present embodiment, the downstream injector 53b is disposed on the downstream side of the main throttle valve 51 on the downstream side of the intake passage of the throttle body 50 so as to be directed to the intake port 37, so that the path to the combustion chamber 36 is provided. The transient response is good because it is short and the arrival time of the fuel is short.
[0050]
Further, according to the present embodiment, since all the injectors can be attached to the throttle body 50 and unitized, the assembly is easy, and the downstream injector 53b is formed between the throttle body 50 below the air cleaner 12 and the cylinder head 31. Since the upstream injector 53a is disposed at a position opposite to the downstream injector 53b on the opposite side of the V-shaped space 12a with the throttle body 50 interposed therebetween, The accompanying fuel piping and harnesses (both not shown) can be disposed in the vicinity of the bottom surface of the air cleaner 12 and the upstream side of the throttle body 50 together with the injector. That is, they can be concentrated and arranged close to the drive motor of the sub throttle valve 52 on the upstream side and its harness, and the throttle lever and throttle cable of the main throttle valve 51 on the downstream side driven by the throttle grip. The degree of freedom in handling can be increased. Therefore, it is possible to save space, and it is possible to mount other fittings by effectively using the space below the air cleaner 12.
[0051]
The intake control device for a fuel injection engine according to the present invention is not limited to the illustrated example described above, and can be variously modified without departing from the scope of the present invention. In this embodiment, the upstream injector 53a is mainly used in the high speed region, and the downstream injector 53b is mainly used in the low speed region and the air-fuel ratio correction, etc., thereby improving the excellent transient characteristics, responsiveness, engine output and It is also possible to reduce HC at the same time.
[0052]
【The invention's effect】
As described above, according to the intake control device for a fuel injection type engine of the present invention, the deviation of the mixture concentration is reduced and the atomization / homogenization of the injected fuel is improved to improve the engine output and the exhaust gas. It has an excellent effect that it can improve the purification and achieve both the transient response of the engine and the improvement of the output.
[0053]
Specifically, according to the present invention, as a flow rate adjusting means, a sub-throttle valve on the intake upstream side having a rotating shaft orthogonal to the intake passage and opened / closed by a motor drive according to the operating state of the engine, and orthogonal to the intake passage A main throttle valve on the downstream side of the intake air that is provided in parallel with the sub-throttle valve and opens and closes in conjunction with the operation of the throttle grip, and the injector for the low rotation range includes the main throttle intake port on the extension of the fuel injection angle range a intake downstream of the rotation shaft of the valve is disposed so as to be positioned, the high rotation region injector is the rotation axis of the sub-throttle valve sandwiched therebetween to directing the sub-throttle valve pivot shaft as well as the intake passage substantially perpendicular to the opposite side of the throttle body side with the low rotation region injector Is disposed so as, as the fuel injection such that fuel directly impinges on the surface and the sub-throttle valve rotating shaft located on the intake downstream side of the sub-throttle valve, the rotation region of the engine, the upstream high By controlling the fuel injection of the low-range injector and the low-range injector on the downstream side, fuel atomization is promoted and the mixture is made uniform, improving engine output and purifying exhaust (reducing HC) Can be achieved.
Furthermore, since the upstream injector is an injector for a high engine speed range and the downstream injector is an injector for a low engine speed range, both transient response and engine output can be improved.
[Brief description of the drawings]
FIG. 1 is an overall side view showing an overall configuration of a motorcycle on which an engine employing an intake control device for a fuel injection type engine according to an embodiment of the present invention is mounted.
FIG. 2 is a partial cross-sectional side view showing a configuration of an engine in which the intake control device is incorporated.
FIG. 3 is an explanatory diagram showing an operation when the throttle valve in the intake control device is in an idle state.
FIG. 4 is an explanatory diagram showing an operation when the throttle valve is fully opened in the intake control device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Motorcycle 12 Air cleaner 12a Space 30 Engine 36 Combustion chamber 37 Intake port 47 Intake passage 50 Throttle body 51 Main throttle valve 51s, 52s Rotating shaft 52 Sub throttle valve 53a Upstream injector 53b Downstream injector 100 Intake control device

Claims (2)

High-revolution region injectors and low-revolution region injectors as fuel injection means for injecting fuel supplied from the fuel pump into the intake passage, and main throttle valve as flow rate adjusting means for controlling the intake air flow rate in the intake passage And an intake control device for a fuel injection engine having a throttle body with a sub-throttle valve,
The sub-throttle valve is disposed on the intake upstream side of the main throttle valve that opens and closes in conjunction with the operation of the throttle grip, and is opened and closed by a motor drive according to the operating state of the engine.
The low rotation region injector is disposed such that an intake port is positioned on an extension of the fuel injection angle range on the intake downstream side of the rotation axis of the main throttle valve,
The high rotation region injector is substantially perpendicular to the intake passage on the side of the throttle body opposite to the low rotation region injector across the rotation shaft of the sub throttle valve and is directed to the sub throttle valve rotation shaft. An intake control device for a fuel injection type engine, wherein the fuel injection is performed so that the fuel directly collides with a surface located on the intake downstream side of the sub-throttle valve and the rotation shaft of the sub-throttle valve. . Tilt the throttle body with respect to the cylinder axis direction of the engine and connect it to the cylinder head.
An air cleaner is disposed above the throttle body and cylinder head,
A downstream injector is housed in a V-shaped space formed between the throttle body and the cylinder head below the air cleaner;
2. The intake control device for a fuel injection engine according to claim 1, wherein the upstream injector is disposed at a position opposite to the V-shaped space on the opposite side of the V-shaped space across the throttle body.

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