JP3925550B2 - Intake control device for fuel injection engine - Google Patents

Description

  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.

  In general, in an internal combustion engine such as an in-vehicle engine, a piston is provided in a cylinder block so as to be reciprocally movable, and the piston is connected to a crankshaft of the internal combustion engine via a connecting rod. The reciprocating movement of the piston is converted into the rotation of the crankshaft by the connecting rod.

  A cylinder head is attached to the cylinder block, and a combustion chamber is provided between the cylinder head and the head of the piston. The cylinder head is provided with an intake passage and an exhaust passage communicating with the combustion chamber. The intake passage is provided with a throttle valve for controlling the amount of air flowing through the passage, and an injector for injecting fuel into the intake passage toward the combustion chamber. The cylinder head is provided with a spark plug for igniting the mixed gas in the combustion chamber.

  In the intake stroke of the internal combustion engine, air is sucked into the intake passage toward the combustion chamber, fuel is injected from the injector, and the combustion chamber is filled with a mixed gas composed of the air and fuel. Thereafter, in the compression stroke of the internal combustion engine, the mixed gas in the combustion chamber is compressed by the movement of the piston. The compressed mixed gas is ignited by an ignition plug and explodes. Due to the explosive force, the piston moves in the opposite direction to move the internal combustion engine to the explosion stroke. Thereafter, in the exhaust stroke of the internal combustion engine, the exhaust gas in the combustion chamber is discharged to the outside through the exhaust passage by the movement of the piston.

  In the engine configured as described above, in recent years, a method of performing optimal intake control by providing a sub-throttle valve in the intake passage and opening and closing the sub-throttle valve according to the operating state of the engine is known for intake control. ing.

For example, as disclosed in Japanese Utility Model Publication No. 3-116740, an optimal intake air can be obtained by arranging a first throttle valve and a second throttle valve in the intake passage and performing air control based on the engine temperature. There has been proposed a control system. According to this method, since the intake air is controlled by providing the bypass passage, it is possible to prevent the engine stall from occurring even when the second throttle valve is fully closed.
In addition, as disclosed in Japanese Utility Model Publication No. 5-3231, the first throttle valve and the second throttle valve are arranged in the intake passage, and the two throttle valves are interlocked by a link mechanism. It has been proposed that the second throttle valve is forcibly fully closed in a state where the first throttle valve has reached the fully open position. According to this method, when the first throttle valve interlocked with the accelerator has trouble and becomes uncontrollable, and the first throttle valve reaches the fully open position, the second throttle valve is forcibly fully closed. Since the engine can be stopped, safety can be ensured.
Japanese Utility Model Publication No. 3-116740 Japanese Utility Model Publication No. 5-3231

However, in the system employing the second throttle valve, that is, the so-called sub-throttle valve as described above, a motor is generally used as a drive actuator for the sub-throttle valve, and this motor controls the sub-throttle valve. It is currently used only for things.
Further, the sub-throttle valve is effective when the main throttle valve is in the middle to high opening state of the engine, and cannot be effective when the main throttle valve is closed.

  Also known is a method of performing FID (first idle) at the time of engine start by controlling the bypass passage area with cooling water and wax, but idling while maintaining the engine speed at a high speed until the water temperature rises. There is a problem that operation is performed and controllability is poor. Furthermore, there is a problem that it is necessary to secure a bypass passage, resulting in an increase in cost and weight.

  On the other hand, as a problem of the conventional engine, in the case of a method in which the FID lever is manually operated at the time of cold start of the engine, even after the warm-up operation is finished, the lever is forgotten to be returned and left in the FID state for normal operation. There is a problem that it is not preferable for the engine and the environment.

  The present invention has been made in view of the above-described conventional problems, and is a fuel injection type capable of realizing the first idle automatic control with a simple configuration by combining the control of the sub-throttle valve and the FID control in the intake control. An object of the present invention is to provide an intake control device for an engine.

The present invention relates to an intake air control system for a fuel injection engine, and is a fuel injection engine having an injector for injecting fuel, and a throttle body to which the injector is attached is provided with a throttle grip operated by a driver. In an intake control device for a fuel-injection engine comprising a main throttle valve that opens and closes and a sub-throttle valve that opens and closes by driving a motor in accordance with the operating state of the engine, the engine includes a water temperature sensor that detects a cooling water temperature of the engine, An electronic control unit that inputs a detection value from the water temperature sensor and controls the opening and closing of the sub-throttle valve, and the electronic control unit has a predetermined time when the water temperature that is input when the engine is started is lower than a set value. During this time, the sub-throttle valve is opened by motor driving, Wherein the opening a predetermined angle of the main throttle valve to transmit the rotation in the opening direction of the throttle valve to the main throttle valve.

As described above, according to the intake control apparatus for a fuel injection engine according to claim 1 of the present invention, the engine inputs a water temperature sensor for detecting the cooling water temperature of the engine and a detection value from the water temperature sensor. And an electronic control unit that controls the opening and closing of the sub-throttle valve. The electronic control unit opens the sub-throttle valve by driving the motor when the water temperature input at the time of starting the engine is lower than a set value. Since the rotation of the throttle valve in the opening direction is transmitted to the main throttle valve to open the main throttle valve at a predetermined angle, when the main throttle valve is in a closed state, the sub-throttle valve is opened by driving the motor. Open the main throttle valve at a slight angle.

Accordingly, the sub-throttle valve is opened by driving the motor for a certain period of time during cold start of the engine where the water temperature input at engine start is lower than the set value, and the rotation of the sub-throttle valve in the opening direction is transmitted to the main throttle valve. Thus, the main throttle valve can be opened by a small angle. As a result, the main throttle valve can be forcibly opened at a minute angle, so that the first idle control can be automatically performed with the main throttle valve opened from the fully closed state by a minute angle.

  Therefore, the choke valve, the choke lever, and the operating cable used at the time of cold starting of the conventional engine can be eliminated. This eliminates the trouble of manually operating the choke lever and prevents forgetting to return the choke. Furthermore, it is possible to reliably perform the starting operation when the engine is cold.

  Furthermore, by providing a water temperature sensor that detects the cooling water temperature and an electronic control device that controls the opening and closing of the sub-throttle valve, it is possible to detect the cooling water temperature at the start of the engine and perform the first idle for a certain period of time. It is possible to improve the engine startability and to achieve an excellent effect of avoiding forgetting to return the choke.

  According to the present invention, even when the throttle grip is closed in the high rotation range and the main throttle valve is fully closed, the main throttle valve is maintained at a minute angle open state by opening the sub throttle valve. Therefore, the amount of air supplied into the combustion chamber can be increased to prevent the air-fuel mixture from becoming rich in advance, and the generation of unburned gas can be suppressed. That is, it is possible to suppress the occurrence of irregular combustion during exhaust. Therefore, there is an excellent effect that it is possible to suppress the occurrence of irregular combustion during exhaust during the deceleration in the high engine speed range.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 to 6 show an example of an embodiment of the present invention. FIG. 1 shows an overall configuration of a motorcycle equipped with an engine that employs an intake control device for a fuel injection engine according to an embodiment of the present invention. 2 is a partially sectional side view showing the configuration of the engine, FIG. 3 is a plan view showing the configuration of the throttle body in the intake control device, FIG. 4 is a view as seen from the arrow A in FIG. 3 is a view as seen from the direction of arrow B in FIG. 3, and FIG. 6 is a view taken along the line CC of FIG.

  In the present embodiment, as shown in FIG. 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 rotatable left and right. On the other hand, a swing arm 9 extending rearward and pivotally supporting the rear wheel 8 is supported on the pivot shaft 7 installed at the center of the vehicle body frame 2 so as to be pivotable up and down. It is buffered and suspended by a suspension mechanism (not shown) provided at the base end.

  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.

  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.

  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.

  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.

  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.

  The engine 30 is a four-cylinder four-cycle engine, and as shown in FIG. 2, a piston 33 is provided in a cylinder block 32 so as to be able to reciprocate. The piston 33 is connected to the output of the engine 30 via a connecting rod 34. It is connected to a crankshaft 35 that is a shaft. 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.

  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.

  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.

  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 is disposed upstream of the intake manifold 45.

  As shown in FIGS. 2 to 6, four throttle bodies 50 are arranged in parallel corresponding to each cylinder, and a main throttle valve 51 that opens and closes in conjunction with the operation of the throttle grip 70. A sub-throttle valve 52 that opens and closes by driving a motor in accordance with the operating state of the engine and a fuel injection valve 53 for injecting fuel are provided. The sub-throttle valve 52 is disposed upstream of the main throttle valve 51 in the air flow direction, and the fuel injection valve 53 is disposed downstream of the main throttle valve 51 in the air flow direction.

  The main throttle valve 51 is integrally attached to a rotation shaft 55 that is rotatably attached to the throttle body 50. As shown in FIG. 4, a main throttle pulley 56 for operating the main throttle valve 51 is provided integrally with the rotating shaft 55 at one end 55 a of the outer periphery of the throttle body 50 of the rotating shaft 55. It has been. A throttle position sensor 57 for confirming the operating state of the main throttle valve 51 is provided at the other end 55 b of the outer periphery of the throttle body 50 of the rotating shaft 55.

  The main throttle pulley 56 is operated via a throttle wire (not shown) that is pushed and pulled in conjunction with the operation of the throttle grip 70 operated by the driver, and opens and closes the main throttle valve 51. . By adjusting the opening degree of the main throttle valve 51, the amount of air taken into the combustion chamber 36 is adjusted.

  The sub-throttle valve 52 is integrally attached to a rotation shaft 58 that is rotatably attached to the throttle body 50. A cam lever 60 for transmitting the operation of the sub-throttle valve 52 is disposed at one end 58 a of the outer periphery of the throttle body 50 of the rotating shaft 58. The other end 58 b of the outer periphery of the throttle body 50 of the rotating shaft 58 is connected to the drive motor 54 of the sub-throttle valve 52. The motor 54 is installed behind the position where the intake passage 47 of the engine 30 on the inner surface of the main frame 2b is disposed.

  A stopper cam 61 for rotating the main throttle pulley 56 is rotatably installed adjacent to the main throttle pulley 56 on one side of the outer periphery of the throttle body 50, and the stopper cam 61 and the cam lever An intermediate cam 64 is rotatably installed adjacently to 60.

  The stopper cam 61 has a contact portion 61a protruding at a position facing a part of the intermediate cam 64, and a main throttle valve at a position facing the stopper portion 56a formed integrally with the main throttle pulley 56. The operation part 61b is formed to protrude. A fast idle adjustment bolt 61c is attached to the main throttle valve operating portion 61b, and a contact position with the stopper portion 56a is set in accordance with a protruding amount of the fast idle adjustment bolt 61c, so that a cold start is performed. The opening degree of the main throttle valve 51 during the first idle control is adjusted.

  A valve position adjusting bolt 66 is provided opposite to the stopper portion 56a of the main throttle pulley 56. When the main throttle valve 51 is fully closed, the stopper portion 56a and the valve position adjusting bolt 66 come into contact with each other, and the main throttle The opening degree of the valve 51 is adjusted.

  The intermediate cam 64 has an outer peripheral end portion 64a protruding substantially parallel to the cam lever 60, and a cam operating portion 64b contacting the contact portion 61a of the stopper cam 61 protruding in an arc shape. . One end portion 64 a of the cam lever 60 and one end portion 60 a of the cam lever 60 are slidably connected via a link bar 62. That is, the cam lever 60, the link bar 62, and the intermediate cam 64 constitute a link mechanism 65.

Next, operations of the main throttle valve 51 and the sub throttle valve 52 of the intake air control apparatus according to the present embodiment will be described with reference to the drawings.
7A is a throttle body configuration diagram showing the state of the link mechanism when the sub-throttle valve is fully closed, and FIG. 7B is a throttle body configuration showing the operation of the link mechanism when the sub-throttle valve is fully open. FIG.

First, when the engine is stopped, as shown in FIG. 7A, the sub-throttle valve 52 is in a fully closed state, and the sub-throttle valve 52 is arranged substantially horizontally in the drawing. Further, the cam operating portion 64 b of the intermediate cam 64 is disposed at a position where it does not contact the contact portion 61 a of the stopper cam 61.
At this time, the main throttle valve 51 is in a fully closed state, and the stopper portion 56a positions the main throttle valve 51 in contact with the valve position adjusting bolt 66.
The stopper portion 56a and the first idle adjustment bolt 61c are not in contact with each other.

  Next, when the engine is cold started, as shown in FIG. 7B, the sub-throttle valve 52 is fully opened, and the sub-throttle valve 52 rotates approximately 90 degrees counterclockwise and is shown in the figure. It is opened in a substantially vertical state. As a result, the cam lever 60 swings approximately 90 degrees counterclockwise, and the link bar 62 is pulled toward the cam lever 60 side. Then, the one end portion 64a of the intermediate cam 64 swings counterclockwise toward the cam lever 60, whereby the intermediate cam 64 rotates, and the cam operating portion 64b swings counterclockwise substantially to the upper right as shown in the figure. Move.

At this time, the cam operating portion 64b contacts the contact portion 61a, and further rotates upward, whereby the stopper cam 61 rotates approximately 15 degrees clockwise. The main throttle valve operating portion 61b swings clockwise toward the stopper portion 56a, the first idle adjustment bolt 61c and the stopper portion 56a come into contact with each other, and the stopper portion 56a swings a small angle counterclockwise. To do. As a result, the main throttle valve 51 rotates counterclockwise in a direction that opens a minute angle.
In this way, by opening the sub throttle valve 52 at the time of cold engine start, the main throttle valve 51 can be opened at a minute angle (for example, approximately 1 degree) necessary for the first idle.

  Then, after idling is performed for a predetermined time after the engine is started, the sub-throttle valve 52 is rotated clockwise and returned to a substantially horizontal position again. Along with this, the intermediate cam 64 swings clockwise, the contact between the cam operating portion 64b and the contact portion 61a is released, and the stopper cam 61 is returned counterclockwise under the urging force of the return spring 67. . Then, when the first idle adjustment bolt 61c is returned, the stopper portion 56a is returned clockwise until it comes into contact with the valve position adjustment bolt 66. In this way, the main throttle valve 51 can be brought into a normal operation state.

Since it is configured as described above, according to the present embodiment, the main throttle valve 51 and the sub-throttle valve 52 are interlocked by the link mechanism 65, so that the main throttle can be configured only by an angle required for first idle with a simple configuration. The valve 51 can be opened.
Further, since the first idle adjustment bolt 61c is provided on the stopper cam 61, the opening angle of the main throttle valve 51 at the time of the first idle can be finely adjusted.
Furthermore, by adjusting the first idle adjusting bolt 61c, not only the opening degree of the main throttle valve but also the opening start time can be arbitrarily set.

  Further, according to the present embodiment, the engine state at the time of starting the engine is detected by the water temperature sensor, and the first idle is performed for a certain period of time, so that the choke lever is not required and the startability of the engine is improved. Improvements can be made.

Further, according to the present embodiment, the cam lever 60, the stopper cam 61 and the intermediate cam 64 are gathered adjacent to one side of the throttle body 50, so that the entire throttle body can be reduced in size without increasing the size of each component. Moreover, the operability of the valve can be improved.
In addition, since the motor for driving the sub-throttle valve and the throttle position sensor are arranged on the same side of the throttle body, the harnesses related to electrical equipment can be integrated and workability can be improved, and the surroundings of the apparatus can be simplified.

  Further, according to the present embodiment, the amount of forced rotation of the main throttle valve 51 by the stopper cam 61 can be arbitrarily performed while the sub throttle valve 52 is kept fully open during the idling operation during the fast idle control. During idling, the main throttle valve 51 is closed, so that even if the sub-throttle valve 52 is fully opened, there is no influence. Accordingly, the amount of forced rotation by the cam can be finely adjusted in this state.

  In this embodiment, a link mechanism is adopted as the interlocking mechanism between the main throttle valve and the sub-throttle valve. However, the present invention is not limited to this. For example, a chain is used for the interlocking mechanism. It may be one in which each throttle valve is interlocked, or one in which the operation of each throttle valve is transmitted using a gear.

1 is an overall side view showing the overall configuration of a motorcycle equipped with an engine that employs an intake control device for a fuel injection type engine according to an embodiment of the present invention. It is a fragmentary sectional side view which shows the structure of the said engine. It is a top view which shows the structure of the throttle body in the said intake control apparatus. It is A arrow directional view of FIG. FIG. 4 is a view taken in the direction of arrow B in FIG. 3. It is CC sectional view taken on the line of FIG. (A) is a throttle body configuration diagram showing the state of the link mechanism when the sub-throttle valve is fully closed, and (b) is a throttle body configuration diagram showing the operation of the link mechanism when the sub-throttle valve is fully open. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Motorcycle 2 Body frame 30 Engine 50 Throttle body 51 Main throttle valve 52 Subthrottle valve 53 Fuel injection valve (injector)
54 Motor 55 Main throttle valve rotation shaft 56 Main throttle pulley 57 Throttle position sensor 58 Sub throttle valve rotation shaft 60 Cam lever 61 Stopper cam 62 Link bar 64 Intermediate cam 65 Link mechanism 70 Throttle grip 100 Intake control device

Claims (1)

A fuel injection type engine having an injector for injecting fuel, a throttle body to which the injector is attached, a main throttle valve that is opened and closed by a throttle grip operated by a driver, and a motor according to an operating condition of the engine In an intake control device for a fuel injection engine comprising a sub-throttle valve that opens and closes by driving,
The engine includes a water temperature sensor that detects a cooling water temperature of the engine, and an electronic control unit that inputs a detection value from the water temperature sensor and controls opening and closing of the sub-throttle valve,
The electronic control unit opens the sub-throttle valve by driving the motor for a certain period of time when the water temperature input at the time of engine start is lower than a set value , and rotates the sub-throttle valve in the opening direction. An intake control device for a fuel injection engine, wherein a main throttle valve is opened at a predetermined angle by transmitting to a valve.

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