JP2013204528A - Intake control device of multi-cylinder engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a throttle control device that can efficiently perform an idling control and deal with a limp home mode by devising a control of two system throttles.SOLUTION: An intake control device of a multi-cylinder engine includes an interlocking mechanism for interlockingly operating a mechanical throttle operation system and an electrical throttle operation system. The interlocking mechanism has a mechanism for interlockingly operate mechanical throttle valves 21 in an open direction thereof by a rotational operation of electrical throttle valves 22 in an open direction thereof, while operating the rotational operation of the electrical throttle valves 22 in the open direction independently of the rotational operation of the mechanical throttle valves 21 in the open direction. The interlocking mechanism has a mechanism for holding the mechanical throttle valves 21 at an idling opening of the entire multi-cylinder engine in a state where the electrical throttle valves 22 are kept substantially fully closed. The electrical throttle control system follows a throttle opening of the mechanical throttle control system obtained by an opening sensor 34.

Description

  The present invention relates to intake control of a multi-cylinder engine, and more particularly to a throttle control device in a multi-cylinder engine having two systems of an electric throttle and a mechanical throttle.

  Conventionally, a multi-cylinder engine that performs cylinder deactivation control has two systems, an electric throttle and a mechanical throttle, and if inconvenience occurs in the electric throttle, fuel cut as a fail process is regulated to avoid engine stop Japanese Patent Application Laid-Open No. 2004-228867 proposes a technique for performing engine control by operating a mechanical throttle in order to cope with limp home (F / S).

JP 2005-282464 A

According to the engine intake control described above, there are two systems of throttle operation, but in normal engine control, only electronic throttle control is executed. The idling speed control tends to require a fine throttle valve opening as the number of cylinders increases, making control difficult.
Further, since the mechanical throttle is used as a dedicated mechanism corresponding to the limp home (F / S), it is considered that the system efficiency is not good.

  The present invention has been proposed in view of the above circumstances. By devising the control of the two systems of throttles, idling control can be simplified and limp home (F / S) correspondence can be efficiently performed. It aims at providing a throttle control device.

In order to achieve the above object, the present invention provides a throttle valve provided in each of the first intake system and the second intake system of the multi-cylinder engine, and the accelerator operation of the driver by the first throttle valve (21). An intake control apparatus for a multi-cylinder engine having a mechanical throttle operating system that operates in conjunction with the engine and an electric throttle operating system that operates the second throttle valve (22) by means of an actuator (35). It is characterized by including.
An interlocking mechanism that interlocks the mechanical throttle operating system and the electric throttle operating system is provided.
The interlocking mechanism causes the first throttle valve (21) to interlock in the opening direction by rotating the second throttle valve (22) in the opening direction of the electric throttle operation system. The opening operation of the second throttle valve (22) includes a lost motion mechanism that operates independently of the opening operation of the first throttle valve (21) in the throttle operation system.
Further, the first throttle valve (21) of the mechanical throttle operating system is set to the multi-cylinder in a state where the electric slot operating system maintains the second throttle valve (22) substantially fully closed. It has a mechanism that maintains the idling opening of the entire engine.
The mechanical throttle operating system includes an opening sensor (34) for detecting the throttle opening of the first throttle valve (21), and the actuator (35) is output from the opening sensor (34). Is driven to cause the throttle opening of the second throttle valve (22) to follow the throttle opening of the first throttle valve (21).

  According to a second aspect of the present invention, in the intake control apparatus for a multi-cylinder engine according to the first aspect, the throttle opening at which the multi-cylinder engine is in a fully closed position when the multi-cylinder engine is idling is determined by the first throttle valve (21 ) Is controlled so as to coincide with the throttle opening of the second throttle valve (22) of the electric throttle operation system.

  According to a third aspect of the present invention, in the multi-cylinder engine intake control device according to the first aspect, the engine throttle control system controls engine output until the multi-cylinder engine is out of an idling state and reaches a low output region, and the electric throttle control The system side is characterized in that it performs control to maintain the fully closed state.

  According to a fourth aspect of the present invention, in the intake control apparatus for a multi-cylinder engine according to the first aspect, when a high output of the multi-cylinder engine is required, the mechanical throttle operation system side is preferentially driven, and then the electric throttle operation system The drive control which the side follows follows.

  According to a fifth aspect of the present invention, in the multi-cylinder engine intake control apparatus according to the first aspect, the multi-cylinder engine is an in-line or V-type four-cylinder and is controlled by grouping every two cylinders.

  According to a sixth aspect of the present invention, in the intake control apparatus for a multi-cylinder engine according to the first aspect, when an abnormality is detected in the electric throttle operation system, the engine is controlled by the mechanical throttle operation system.

  According to the configuration of the first aspect of the present invention, the interlocking mechanism for interlockingly operating the first throttle valve (21) in the opening direction by the rotational operation in the opening direction of the second throttle valve (22) of the electric throttle operation system is provided. Thus, the mechanical throttle operation is detected by the opening sensor (34) of the throttle valve opening while the first throttle valve (21) of the mechanical throttle operation system is driven by the electric throttle operation system. The actuator (35) causes the second throttle valve (22) of the electric throttle operation system to follow mechanically.

  On the other hand, when the second throttle valve (22) of the electric throttle operating system is in a fully closed state, the first throttle valve (21) of the mechanical throttle operating system is opened slightly the same as the second throttle valve (22). Therefore, the second throttle valve (22) is not controlled by the minute opening in the idling state, and the idling speed can be controlled by the mechanical throttle valve opening with a relatively small opening. It is possible to realize idling in a cylinder with an increased combustion state.

  Further, when the throttle opening at idling changes due to secular change, the first throttle valve (21) of the mechanical throttle operating system can be interlocked and controlled in the opening direction by the actuator (35). Idling stability can be ensured.

Furthermore, even if an abnormality occurs in the electric throttle operation system (failure), the first throttle valve (21) of the mechanical throttle operation system is independent of the second throttle valve (22) in the opening direction. Since it is an interlocking mechanism capable of rotating, the first throttle valve (21) can be mechanically operated to maintain the minimum driving operation against the failure of the electric throttle operation system. it can.
Therefore, in contrast to controlling all the intake systems of the multi-cylinder engine with the actuator (35), it is possible to realize good control in idling control and fail control.

  According to the configuration of the second aspect, when the multi-cylinder engine is in the idling state, the second throttle valve (22) of the electric throttle operation system is set with respect to the throttle opening of the first throttle valve (21) of the mechanical throttle operation system. ), The engine rotation stability is improved during idling without throttle operation.

  According to the third aspect of the present invention, the engine output is controlled only by the first throttle valve (21) of the mechanical throttle operation system until the low output region is released from the idling state. A torque feeling of a two-cylinder engine can be obtained.

  According to the fourth aspect of the present invention, when a high output is required, the second throttle valve of the electric throttle operating system (with respect to the throttle opening of the first throttle valve (21) of the mechanical throttle operating system). 22) By performing control that the side follows, the feeling of engine blow-up on the high output side is improved.

  According to the configuration of claim 5, the four-cylinder engine is grouped into two cylinders, and the output of the two-cylinder engine can be obtained from the idling state to the low output region, and the output of the four-cylinder engine can be obtained when the high output is requested. Thus, efficient output characteristics suitable for two-wheeled vehicles can be obtained.

  According to the configuration of the sixth aspect, the engine can be controlled by the mechanical throttle operation system when an abnormality is detected in the electric throttle operation system. Therefore, the intake control system considering the limp home (F / S) correspondence, can do.

FIG. 3 is an explanatory side sectional view of a cylinder head and its vicinity in an intake control device for a multi-cylinder engine of the present invention. (A)-(c) is a model figure which shows the structure of the intake control apparatus of the multicylinder engine which concerns on one Embodiment of this invention. 1 is a schematic control system block diagram of an intake control device for a multi-cylinder engine of the present invention. It is a graph which shows the output characteristic curve obtained with the intake control apparatus of the multicylinder engine of this invention. (A)-(c) is a model figure which shows the structure of the intake control apparatus of the multicylinder engine which concerns on other embodiment of this invention.

  An example of an embodiment of an intake control device for a multi-cylinder engine of the present invention will be described with reference to the drawings. An intake control device for a multi-cylinder engine according to an embodiment of the present invention is applied to, for example, a water-cooled 4-stroke in-line 4-cylinder engine mounted on a motorcycle. The in-line four-cylinder engine is arranged so that four cylinders are arranged in the vehicle width direction (front and back direction in FIG. 1).

  Four cylinder bores (cylinders) 3 are formed in the cylinder block 2 of the engine 1 in the rear surface direction of FIG. 1, and pistons 4 are inserted into the cylinder bores 3 so as to be movable up and down. The cylinder head 5 that is coupled to the cylinder block 2 is formed with a combustion chamber 6 that is recessed facing the top surface of the piston 4, and an intake port 7 and an exhaust port 8 that open to the combustion chamber 6. However, two of them are formed.

  The two intake ports 7 extend obliquely upward from the opening of the combustion chamber 6 to the rear, and the two exhaust ports 8 extend obliquely upward from the opening of the combustion chamber 6 to the front. The opening of the intake port 7 to the combustion chamber 6 is performed by opening and closing the valve body of the intake valve 9 that slides up and down, and the opening of the exhaust port 8 to the combustion chamber 6 is exhausted up and down to slide. This is performed by opening and closing the valve body of the valve 10. An intake pipe 11 is communicated with each intake port 7 and is adjusted by adjusting the opening (throttle opening) of a throttle valve 20 that is mounted in the intake pipe 11 and operates to close the intake passage by the rotation of the valve shaft 12. The amount of air to the port 7 is adjusted. In addition, an injector 13 for performing fuel injection is disposed on the downstream side of the throttle valve 20 of the intake pipe 11.

Next, a characteristic configuration of the multi-cylinder engine intake control apparatus of the present invention will be described with reference to a model diagram of an intake pipe portion of the engine (four cylinders) shown in FIG. 2, parts having the same configuration as in FIG. 1 are denoted by the same reference numerals.
The plurality of intake pipes 11 constituting the multi-cylinder (four-cylinder) engine are divided into a first intake system that controls two cylinders and a second intake system that controls the remaining two cylinders (every two cylinders). To be divided). Disc-shaped first throttle valves 21 and 21 are arranged in each intake pipe 11 constituting the first intake system, and each disc-like second pipe constituting the second intake system is provided with a disc-like second one. Throttle valves 22 and 22 are arranged.

The first intake system by the first throttle valve 21 constitutes a mechanical throttle operation system that is operated in conjunction with the driver's accelerator operation. The throttle valves (first throttle valves) 21 and 21 are connected by a valve shaft 12A. The valve shaft 12A protrudes through the side wall of the intake pipe 11, and a disc-shaped operation plate 31 is mounted on the end thereof. ing. Two open and closed wires 32 and 33 extending from a throttle grip (not shown) are wound around the circumference of the working plate 31 in opposite directions, and the tips of the wires are wound around the working plate 31. It is bound.
The operation plate 31 is biased by a spring (not shown) in a direction in which the integrated throttle valves 21 and 21 close the intake passage of the intake pipe 11 via the valve shaft 12A.

Therefore, when the opening side throttle wire 32 is pulled by the accelerator operation of the throttle grip and the closing side throttle wire 33 is pushed, the operating plate 31 rotates against the urging force of the spring, and the throttle plate integrated with the operating plate 31 is operated. The valves 21 and 21 rotate in a direction to open the intake passage, and the inclination (throttle opening) of the throttle valve 21 with respect to each intake pipe 11 is adjusted. Therefore, a mechanical throttle operation system is configured in which the throttle opening of the throttle valve 21 is controlled via the throttle wires 32 and 33 by adjusting the throttle grip.
Further, an APS sensor (accelerator position sensor) 34 that detects the throttle valve opening degree by detecting the rotation state of the valve shaft is disposed on the valve shaft 12A side of the operation plate 31.

The second intake system by the second throttle valve 22 constitutes an electric throttle operation system that is operated by an actuator by electrical control.
Each throttle valve (second throttle valve) 22, 22 is connected by a valve shaft 12 </ b> B, and its end is fixed to the rotating shaft of a TBW motor (actuator) 35. Therefore, the throttle opening is adjusted by tilting the throttle valve 22 with respect to the intake pipe 11 by the rotation of the valve shaft 12B.

Each throttle valve (second throttle valve) 22 of the electric throttle operation system has its throttle opening detected by a throttle valve opening sensor 41 mounted in the vicinity of the rotating shaft of a TBW motor (actuator) 35. The throttle valve opening is controlled by the TBW motor 35 driven by the feedback driving means, and the second throttle valve is controlled to be fully closed when the throttle opening is slightly opened.
Further, the second throttle valve 22 follows the throttle opening degree of the first throttle valve 21 by driving the TBW motor 35 by the output of the APS sensor 34 that detects the opening degree of the first throttle valve 21 described above. Is made.

The disc portion 51 attached to the end of the valve shaft 12A of the mechanical throttle operation system and the disc portion 52 attached to the end of the electric throttle operation system are opposed to each other, and each circle An interlocking mechanism is formed on the plate portion by forming projections 53 and 54 protruding perpendicularly to the disk surface near the outer periphery where they can come into contact with each other.
In the interlocking mechanism, when the disk portion 52 of the electric throttle operation system rotates in the clockwise direction (throttle valve open side), and the disk portion 51 of the mechanical throttle operation system rotates in the counterclockwise direction (throttle The projections 53 and 54 are configured to come into contact with each other when rotating to the valve closing side.
The disk portion 51 of the mechanical throttle operation system is configured to include a lost motion mechanism that can rotate independently of the electric throttle operation system in the clockwise direction (throttle valve opening side). The disk portion 52 of the electric throttle operation system can rotate independently of the mechanical throttle operation system in the counterclockwise direction (throttle valve closing side). The valve 22 is fully closed when the throttle opening is slightly opened.

Next, the operation of the mechanical throttle operation system and the electric throttle operation system in the intake control device described above will be described.
(When idling)
When the throttle grip accelerator is not operated, the closing throttle wire 33 is pulled by the biasing force of the spring and the opening throttle wire 32 is pushed, so that the throttle valve 21 integrated with the operating plate 31 and the valve shaft 12A is integrated. , 21 rotate in the direction to close the intake passage (counterclockwise direction), and the throttle valve 21 operates in the direction in which the intake passage of each intake pipe 11 is closed. 53 abuts on the protrusion 54 provided on the disc portion 52 of the electric throttle operation system, so that the disc portion 52 follows and rotates, and the rotation is restricted in the fully opened state of the electric throttle operation system. (FIG. 2A).

In the fully closed state of the electric throttle operation system, the second throttle valves 22 and 22 are held in a slightly opened state by the control of the TBW motor 35, so that the first throttle valve 21 and 21 is also held at the same throttle opening as the second throttle valves 22 and 22 (the projection 54 serves as a stopper mechanism for the projection 53), and this throttle opening is equal to the idling opening of the entire multi-cylinder engine. Become.
That is, the throttle opening at which the multi-cylinder engine is in the fully closed position in the idling state is the throttle opening of the first throttle valve 21 of the mechanical throttle operation system, and the throttle opening of the second throttle valve 22 of the electric throttle operation system. Control to match the throttle opening is performed.

  When the mechanical throttle operating system and the electric throttle operating system are operated independently, the amount of leakage due to the throttle valve position of the mechanical throttle operating system is mechanically determined, so the electric throttle operating system (TBW side output) The output balance between cylinders is lost and the stability of idling speed is deteriorated. However, as described above, the throttle valve of the mechanical throttle operating system is an electric throttle when idling. By adopting a structure that can maintain the same throttle opening as the throttle valve of the operation system, it is possible to ensure the stability of the idling rotational speed.

(When the throttle is open)
When the accelerator operation of the throttle grip is performed, the opening-side throttle wire 32 is pulled and the closing-side throttle wire 33 is pushed, so that the operation plate 31 rotates against the urging force of the spring and is integrated with the operation plate 31. The throttle valves 21 and 21 rotate in a direction (clockwise direction) to open the intake passage, and the inclination (throttle opening) of the throttle valve 21 with respect to each intake pipe 11 is adjusted. At this time, the mechanical throttle operation system can rotate independently regardless of the electric throttle operation system (FIG. 2B).

(TBW following)
When the throttle opening of the first throttle valve 21 or 21 of the mechanical throttle operation system is adjusted by the accelerator operation of the throttle grip, the throttle opening is detected by the APS sensor 34 and the TBW motor 35 is controlled. Then, the throttle opening degree of the second throttle valves 22 and 22 is made to follow the throttle opening degree of the first throttle valves 21 and 21 (FIG. 2C).

FIG. 3 shows an outline of a control system block diagram of a control device for controlling a throttle valve by a mechanical throttle operation system and an electric throttle operation system.
The TBW motor 35 is driven and controlled by an electronic control unit ECU 80 mounted on the vehicle. The throttle control means 81 of the ECU 80 controls the throttle opening of the first throttle valves 21 and 21 of the mechanical throttle operation system based on the detection value of the opening sensor 34 that detects the operation amount of the throttle grip, and the opening sensor The throttle opening degree of the second throttle valves 22 and 22 is controlled by the detected value 34. Further, when the TBW motor 35 is driven, feedback control is performed by inputting the detection value of the throttle valve opening sensor 41.
In the throttle control means 81, when the accelerator operation of the throttle grip is small (low output side) (the multi-cylinder engine leaves the idling state up to the low output range), the engine output is controlled by the mechanical throttle operation system to be electrically operated. The throttle operating system side is controlled to be kept in a fully closed state. If the throttle grip accelerator operation is higher than a predetermined value (high output side), the mechanical throttle operating system side is driven preferentially, and then the electric throttle Drive control that the operation system side follows is performed.

  Further, the ECU 80 includes abnormality determining means 82 for determining whether or not the electric throttle operation system is functioning normally and whether or not there is an abnormality in the control system, and when the abnormality determining means 82 determines that there is an abnormality. In addition, there is a fail process execution means 83 for executing a fail process (corresponding to limp home) of the electric throttle operation system.

  Each detection signal is input to the abnormality determining means 82 from the throttle valve opening sensor 41, the vehicle speed sensor 42, the engine speed sensor 43, and the throttle grip opening sensor 34, and the presence or absence of abnormality is determined.

FIG. 4 is a graph showing torque characteristics with respect to the throttle opening (TH) by the accelerator operation of the throttle grip.
The output for two cylinders with respect to the throttle opening (TH) of the throttle grip of the first throttle valve 21 and 21 by manual operation (by wire) of the mechanical throttle operation system is a torque curve (manual cylinder output) Characteristic). The output for two cylinders with respect to the throttle opening (TH) of the throttle grip of the second throttle valve 22, 22 by the TBW motor 35 of the electric throttle operation system is a torque curve (TBW cylinder output characteristic) like a one-dot chain line. Is obtained. Since the output characteristic is obtained so that the TBW cylinder output follows the manual cylinder output, the entire four-cylinder engine can obtain the output characteristic shown by a solid line obtained by adding both.

From this graph, the electric throttle is controlled by controlling the engine output with a mechanical throttle operation system until the low output side where the throttle opening (TH) of the throttle grip is small, that is, until the multi-cylinder engine leaves the idling state and reaches the low output range. By controlling the operation system to be in the fully closed state, the output is determined only by manual driving, so that a two-cylinder torque feeling can be obtained.
When a high output of a multi-cylinder engine is required, the mechanical throttle operation system side is driven preferentially, and then the drive control that the electric throttle operation system side follows is performed. Since the throttle operation system is driven, it is possible to obtain a torque feeling having a feeling of blowing up like a 4-cylinder.

  In the above-described structure, mechanically controlled throttle valves 21 and 21 are provided in the intake pipe 11 connected to the first cylinder # 1 and the second cylinder # 2 to make them normal operating cylinders. By providing electrically controlled throttle valves 22 and 22 in the intake pipe 11 connected to the No. 3 cylinder # 3 and No. 4 cylinder # 4, the No. 3 cylinder # 3 and No. 4 cylinder are provided when an abnormality occurs in the TBW motor 35. It is possible to set # 4 as a cylinder that can be deactivated, and to perform engine control by a mechanical throttle operation system (regulating fuel cut as a fail process to avoid engine stop).

FIG. 5 shows another embodiment, which is applied to a V-type four-cylinder engine in which cylinders are arranged in a V shape. 5, the same parts as those in FIG. 2 are denoted by the same reference numerals.
Four cylinders are grouped by two, and a disk part 51 is formed at the end of the valve shaft 12A of the mechanical throttle operating system, and a disk plate 52 is formed at the end of the valve shaft 12B of the electric throttle operating system. To do. A wire-side disc portion 61 is attached to the tip of an operating shaft 37 formed on the operating plate 31 that rotates in response to a wire operation. The disc portion 52 mounted on the end of the valve shaft 12B of the electric throttle operation system faces the wire-side disc portion 61 so as to face each other, and is perpendicular to the disc surface of the disc portion 52. The protrusions 63 provided on the wire-side disk part 61 are formed so as to be able to contact the protruding protrusions 54 near the outer periphery of each disk part, and the wire-side disk part 61 and the disk part 51 The link mechanism 70 that rotates in the same direction in conjunction with each other is provided between the mechanical throttle operation system and the electric throttle operation system. The link mechanism 70 is pivotally supported between a support part 71 formed on the disk part 51 and a support part 72 formed on the wire-side disk part 61 so that both ends are rotatable with respect to each support part. The long connecting body 73 is formed.

When the disk portion 52 of the electric throttle operation system rotates in the clockwise direction (throttle valve opening side), the interlocking mechanism 70 contacts the protrusion 54 and the protrusion 63 so that the electric throttle operation system disk The rotation of the part 52 rotates the disk part 51 of the mechanical throttle operation system via the wire side disk part 61 and the link mechanism 70. Further, when the disk portion 51 of the mechanical throttle operation system rotates in the counterclockwise direction (the throttle valve closing side), the protrusions 63 and 54 are connected to each other via the link mechanism 70 and the wire side disk portion 61. Comes into contact with each other, and the disk portion 52 of the electric throttle operation system rotates.
The disk portion 51 of the mechanical throttle operation system can be rotated independently in the clockwise direction (throttle valve opening side) regardless of the electric throttle operation system. The electric throttle operation system disk portion 52 can rotate independently of the mechanical throttle operation system in the counterclockwise direction (throttle valve closing side), but the TBW motor 35 controls the throttle valve 22. When the throttle opening is slightly opened, the valve is fully closed.
In this example, the APS sensor 34 is configured to detect the throttle opening degree of the first throttle valve 21 by detecting the rotation state of the operating shaft 37.
Also in the configuration of this example, as in the structure of FIG. 2, the torque characteristics with respect to the throttle opening by the throttle grip accelerator operation can obtain the output characteristics shown in FIG.

  In each example described above, a four-cylinder engine has been described as an example. However, the present invention can be applied to a multi-cylinder engine that can divide a cylinder into a plurality of groups, such as a six-cylinder or eight-cylinder engine, or an odd-cylinder engine. .

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Cylinder block, 3 ... Cylinder bore (cylinder), 4 ... Piston, 5 ... Cylinder head, 6 ... Combustion chamber, 7 ... Intake port, 8 ... Exhaust port, 9 ... Intake valve, 10 ... Exhaust valve, DESCRIPTION OF SYMBOLS 11 ... Intake pipe, 12 ... Valve shaft, 21 ... 1st throttle valve, 22 ... 2nd throttle valve, 32, 33 ... Throttle wire, 34 ... APS sensor (opening sensor), 35 ... TBW motor (actuator) 41 ... throttle valve opening sensor, 51, 52 ... disc, 53, 54 ... projection, 61 ... wire side disc, 63 ... projection, 70 ... link mechanism, 80 ... ECU, 81 ... throttle control Means 82... Abnormality judgment means 83. Fail processing execution means.

Claims (6)

A throttle valve provided in each of the first intake system and the second intake system of the multi-cylinder engine, and a mechanical throttle operation system that operates the first throttle valve (21) in conjunction with the accelerator operation of the driver. And an intake control device for a multi-cylinder engine including an electric throttle operation system that operates the second throttle valve (22) by an actuator (35).
An interlocking mechanism that interlocks the mechanical throttle operating system and the electric throttle operating system;
The interlocking mechanism is
By rotating the second throttle valve (22) in the opening direction of the electric throttle operating system, the first throttle valve (21) is interlocked in the opening direction, and the mechanical throttle operating system is The first throttle valve (21) includes a lost motion mechanism in which the opening operation of the second throttle valve (22) is independently performed with respect to the rotation operation of the second throttle valve (21);
In a state where the electric slot operation system maintains the second throttle valve (22) substantially fully closed, the first throttle valve (21) of the mechanical throttle operation system is set to the entire multi-cylinder engine. Has a mechanism for maintaining the idling opening of
The mechanical throttle operating system is
An opening sensor (34) for detecting the throttle opening of the first throttle valve (21) is provided, and the actuator (35) is driven by the output of the opening sensor (34) to drive the second throttle valve. An intake control device for a multi-cylinder engine, wherein the throttle opening of (22) is made to follow the throttle opening of the first throttle valve (21).   The throttle opening at which the multi-cylinder engine is in the fully closed position in the idling state is the throttle opening of the first throttle valve (21) of the mechanical throttle operating system, and the second throttle of the electric throttle operating system. The intake control apparatus for a multi-cylinder engine according to claim 1, wherein control is performed so as to match the throttle opening of the throttle valve (22).   2. The control according to claim 1, wherein the engine output is controlled by the mechanical throttle operation system until the multi-cylinder engine leaves the idling state and reaches a low output region, and the electric throttle operation system side is controlled to be fully closed. Intake control device for multi-cylinder engines.   2. The intake of a multi-cylinder engine according to claim 1, wherein when a high output of the multi-cylinder engine is required, the mechanical throttle operation system side is driven preferentially, and thereafter drive control that the electric throttle operation system side follows is performed. Control device.   The multi-cylinder engine intake control device according to claim 1, wherein the multi-cylinder engine is an in-line or V-type four-cylinder and performs control by grouping every two cylinders.   The intake control apparatus for a multi-cylinder engine according to claim 1, wherein when the abnormality of the electric throttle operation system is detected, the engine is controlled by the mechanical throttle operation system.