JPH11141360A - Variable cylinder controller of internal combustion engine with variable valve timing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the torque from abnormally lowering by giving the priority of the cylinder reduction to a bank where an abnormal variable valve timing mechanism (VVT) exists, in a case of the cylinder reduction. SOLUTION: When the cylinder reduction is instructed by the setting of the number above 1 as the number of cylinders to be reduced (nfc) by the traction control, the priority of the cylinder reduction is given to #2 cylinder, #4 cylinder and #6 cylinder belonging to a left bank when the abnormality is found in a left VVT ('YES' in S120), in a VVT (S130-S210), and the priority of the cylinder reduction is given to #1 cylinder, #3 cylinder and #5 cylinder belonging to a right bank when the abnormality is found in the right VVT ('NOI' in S120) (S220-S300). That is, the cylinder of which the torque output is deteriorated, is reduced with the priority on the basis of the abnormality of the VVT when the VVT is abnormal, so that the torque output is not suddenly lowered in the cylinder reduction process. Whereby the generation of the engine stall in the cylinder reduction can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable cylinder control apparatus for an internal combustion engine having a variable valve timing mechanism, and more particularly, to a valve timing of one or both of an intake valve and an exhaust valve in each of a plurality of banks provided in the internal combustion engine. The present invention relates to a variable cylinder control device for an internal combustion engine that includes a variable valve timing mechanism that adjusts the cylinder pressure and that performs a reduced-cylinder operation in accordance with an operating condition.

[0002]

2. Description of the Related Art In traction control, it is detected that a wheel has slipped, and the number of cylinders to be reduced in the internal combustion engine is determined based on the vehicle speed, the amount of intake air of the internal combustion engine, the degree of idling of the wheel, and the like. There is known a system for executing a fuel cut on a vehicle to reduce wheel idling.

[0003] In such an internal combustion engine having a plurality of banks, such as a V-type engine, a cylinder to be subjected to the cylinder reduction is appropriately selected and fuel cut is performed regardless of the affiliation of the bank. Was running.

[0004]

SUMMARY OF THE INVENTION In an internal combustion engine, the valve timing of an intake valve or an exhaust valve is adjusted,
In order to operate the internal combustion engine efficiently according to the operating state,
2. Description of the Related Art An internal combustion engine provided with a variable valve timing mechanism is known. Such a variable valve timing mechanism realizes efficient operation by providing a variable valve timing mechanism for each bank when there are a plurality of banks such as a V-type engine.

However, in the conventional cylinder reduction control, as described above, the cylinder to be reduced is appropriately set regardless of the bank and the cylinder reduction processing such as fuel cut is performed.
If any of the variable valve timing mechanisms fails, a case may occur where the cylinder to be initially subjected to cylinder reduction belongs to a bank to which the normal variable valve timing mechanism is attached.

When the cylinders belonging to the bank in which the normal valve timing is executed are initially reduced,
Since the output on the bank side where the torque is normally generated disappears, the ratio of the output on the bank side where the valve timing is not appropriate and the abnormally low torque is generated increases. For this reason, the torque output as a whole is abnormally reduced, and in the worst case, an engine stall may occur.

Conventionally, when a variable valve timing mechanism fails, a variable valve timing mechanism that has not failed is adapted to the valve timing of the malfunctioning valve in order to prevent torque fluctuation (Japanese Unexamined Patent Application Publication No. Hei. 63922
Is known, but there is no known solution to the above-described problem in the reduced cylinder processing.

According to the present invention, when cylinders are reduced, the cylinders in the bank in which the abnormal variable valve timing mechanism is provided are preferentially targeted for cylinder reduction, thereby preventing abnormal torque reduction. It is the purpose.

[0009]

According to a first aspect of the present invention, there is provided a variable cylinder control apparatus for an internal combustion engine having a variable valve timing mechanism.
Variable cylinder control for an internal combustion engine that includes a variable valve timing mechanism that adjusts the valve timing of one or both of an intake valve and an exhaust valve in each of a plurality of banks provided in the internal combustion engine, and that performs a reduced cylinder operation according to an operating condition An apparatus, comprising: a valve timing adjustment abnormality detecting means for detecting whether the variable adjustment of the valve timing in each of the variable valve timing mechanisms is abnormal; and detecting the abnormality by the valve timing adjustment abnormality detecting means. And a cylinder selecting means for preferentially selecting a cylinder belonging to a bank adjusted by the variable valve timing mechanism to be a target cylinder in the reduced cylinder operation.

As described above, the cylinder-reducing selecting means preferentially sets the cylinder belonging to the bank adjusted by the variable valve timing mechanism detected as abnormal to be the target of the cylinder reduction in the cylinder-reducing operation. Therefore, the cylinders having a normal torque output remain until all the abnormal cylinders are reduced, so that the torque does not decrease more than necessary during the cylinder reduction processing, and the internal combustion engine is brought into a desired operating state. Can be maintained and engine stall can be prevented.

For example, assuming that the internal combustion engine is used as an output engine for driving a vehicle, the driving condition is, for example, as follows.
It is an operating condition of one or both of the vehicle and the internal combustion engine. Thus, by applying the present invention to the internal combustion engine for driving the vehicle, even when the cylinder reduction process is performed, no abnormality occurs in the running of the vehicle. For example, the driving state of the vehicle is a degree of a vehicle speed, a degree of idling of wheels, and the like.
The operating state of the internal combustion engine is, for example, an intake air amount.

According to a third aspect of the present invention, the reduced cylinder selecting means may be configured as follows. That is, if the number of cylinders to be reduced is within the number of cylinders belonging to the bank being adjusted by the variable valve timing mechanism detected as abnormal by the valve timing adjustment abnormality detecting means, only the cylinders in the bank are adjusted. If the number of cylinders to be reduced exceeds the number of cylinders belonging to the bank being adjusted by the variable valve timing mechanism detected as abnormal by the valve timing adjustment abnormality detecting means, With respect to the number of cylinders exceeding, the cylinders belonging to the bank being adjusted by the variable valve timing mechanism, which is detected as not abnormal by the valve timing adjustment abnormality detecting means, are subjected to cylinder reduction.

Thus, the cylinder on the bank side having the abnormality can be preferentially subjected to the cylinder reduction. In addition,
The variable valve timing mechanism is not particularly limited. For example, a first rotating body interlocked with one of the two rotation axes and a second rotation body interlocked with the other of the two rotation axes. A two-rotation body, and a relative rotation between the first rotation body and the second rotation body may allow the rotation phase difference between the two rotation shafts to be variably set within an allowable range. Good. With such a configuration, the valve timing of the internal combustion engine can be switched steplessly.
Alternatively, for example, the valve timing may be switched in a stepwise manner by selecting and switching cams of the intake valve and the exhaust valve from a plurality of cams.

[0014]

FIG. 1 is a schematic configuration diagram showing a gasoline engine system to which the present embodiment is applied.

V-type six-cylinder engine 10 as an internal combustion engine
Includes a cylinder block 11 in which a plurality of cylinders are formed in a V-shape when viewed in the vertical direction of the drawing, a left cylinder head 12L and a right cylinder head 12R connected to an upper portion of the cylinder block 11, respectively. A cylinder group LS and a right cylinder group RS are formed. Hereinafter, these cylinder groups will be referred to as banks. As shown in FIG. 6, the second bank (# 2), the fourth (# 4), and the sixth (# 6) cylinder belong to the left bank LS, and the right bank RS has 1 cylinder.
The third (# 1), third (# 3) and fifth (# 5) cylinders belong.

The engine 10 includes a piston 13 that reciprocates substantially vertically in each cylinder of the cylinder block 11, and a lower end of each piston 13 is connected to a crankshaft 14. By moving up and down, the crankshaft 14 is rotated.

In the vicinity of the crankshaft 14,
A crank angle sensor 40 is provided. The crank angle sensor 40 includes a magnetic rotor (not shown) connected to the crankshaft 14 and an electromagnetic pickup (not shown). Here, teeth are formed at equal angles on the outer periphery of the rotor, and a pulse-like crank angle signal is generated each time the teeth pass in front of the electromagnetic pickup.

Further, after a reference position signal is generated by a cylinder discriminating sensor 42, which will be described later, the number of generated crank angle signals from the crank angle sensor 40 is measured, whereby ECU
At 70 (described later), the rotation speed (engine speed NE) of the crankshaft 14 is calculated.

The space defined by the inner walls of each cylinder block 11, the two cylinder heads 12L and 12R, and the top of the piston 13 functions as a combustion chamber 15 for burning an air-fuel mixture.
An ignition plug 16 for igniting the air-fuel mixture is disposed at the top of L and 12R so as to project into the combustion chamber 15. Distributors 18 are provided in the vicinity of the two exhaust-side camshafts 33L, 33R of the two cylinder heads 12L, 12R, respectively, and each distributor 18 is provided with the rotation of the two exhaust-side camshafts 33L, 33R. A cylinder discrimination sensor 42 for detecting a reference position signal generated at a predetermined rate is provided. The reference position signal is used for detecting the reference position of the crankshaft 14 and determining the cylinder.

Each ignition plug 16 is connected to a distributor 18 via a plug cord or the like (not shown). A high voltage output from the igniter 19 based on an ignition signal from an ECU 70 (described later) The gas is distributed to each spark plug 16 by each distributor 18 in synchronization with the crank angle.

The cylinder block 11 is provided with a water temperature sensor 43 for detecting a temperature (cooling water temperature) THW of the cooling water flowing through the cooling water passage. further,
Each of the two cylinder heads 12L and 12R has an intake port 22 and an exhaust port 32. The intake port 22 is connected to the intake passage 20, and the exhaust port 32 is connected to the exhaust passage 30. ing. Each intake port 22 of the cylinder head 12 has an intake valve 2
1 is disposed, and an exhaust valve 31 is disposed at each exhaust port 32.

Then, each intake valve 2 of the left bank LS
A left intake camshaft 23L for opening and closing the intake valve 21 is disposed above the right bank R.
Above each intake valve 21 of S, a right intake side camshaft 23R for opening and closing the intake valve 21 is arranged. Also, each exhaust valve 31 of the left bank LS
A left-side exhaust-side camshaft 33L for opening and closing the exhaust valve 31 is disposed above the right bank RS.
Above each exhaust valve 31, a right exhaust camshaft 33R for opening and closing the exhaust valve 31 is disposed.

Further, both intake side camshafts 23L, 23
At one end of the 3R, an intake-side timing pulley 27 is provided.
Are mounted, and both exhaust side camshafts 33L, 33
An exhaust-side timing pulley 34 is attached to one end of each R. And, each timing pulley 27, 3
4 is connected to the crankshaft 14 via a timing belt 35.

Therefore, when the engine 10 is operating,
Each camshaft 2 from the crankshaft 14 via a timing belt 35 and timing pulleys 27 and 34
The rotational driving force is transmitted to 3L, 23R, 33L, 33R, and the respective camshafts 23L, 23R, 33L, 33R rotate, whereby the respective intake valves 21 and the respective exhaust valves 31 are opened and closed. These valves 21, 31
Is synchronized with the rotation of the crankshaft 14 and the vertical movement of the piston 13, that is, in synchronization with a series of four strokes of the engine 10 including an intake stroke, a compression stroke, an explosion / expansion stroke, and an exhaust stroke. It is driven at the opening and closing timing.

Further, both intake side camshafts 23L, 2
In the vicinity of 3R, cam angle sensors 44L and 44R are provided, respectively.
Are provided, and each of the cam angle sensors 44L and 44R is
It is composed of a magnetic rotor (not shown) connected to both intake side camshafts 23L, 23R and an electromagnetic pickup (not shown). A plurality of teeth are formed at equal angles on the outer circumference of the magnetic rotor. For example, before the compression TDC of a predetermined cylinder, between 90 ° to 30 ° BTDC,
A pulse-like cam angle signal (displacement timing signal) accompanying the rotation of the intake camshaft 23 is detected.

In the gasoline engine system according to the present embodiment, since the opening / closing timing of the intake valve 21 is changed to change the valve overlap amount,
Variable valve timing mechanisms 50L and 50R (hereinafter, referred to as “VVT”) driven by hydraulic pressure are provided on the intake-side timing pulley 27 of the left bank LS and the right bank RS, respectively. These VVT50L, 50R are
Crankshaft 14 (intake side timing pulley 27)
This is a mechanism for changing the valve timing of the intake valve 21 continuously (steplessly) by changing the displacement angle of both the intake side camshafts 23L, 23R with respect to the rotation of.

Each of the VVTs 50L, 50R has a corresponding oil control valve 80L, 80L.
R (hereinafter referred to as “OCV”), an oil pump 64L,
64R and oil filters 66L and 66R are connected. In the present embodiment, the actuators of the VVTs 50L and 50R are configured by the OCVs 80L and 80R, the oil pumps 64L and 64R, and the like.

An air cleaner 24 is connected to the air intake side of the intake passage 20, and a throttle valve 26 that is opened and closed in conjunction with an accelerator pedal (not shown) is provided in the middle of the intake passage 20. ing. The intake air amount is adjusted by opening and closing the throttle valve 26.

In the vicinity of the throttle valve 26, a throttle sensor 4 for detecting a throttle opening TA is provided.
5 are provided. Further, the throttle valve 26
A surge tank 25 for suppressing intake pulsation is formed on the downstream side. The surge tank 25 is provided with an intake pressure sensor 46 for detecting an intake pressure PM in the surge tank 25. An injector 17 for supplying fuel to the combustion chamber 15 is provided near the intake port 22 of each cylinder. Each injector 17 is an electromagnetic valve that is opened by energization, and each injector 17 is supplied with fuel pumped from a fuel pump (not shown).

Therefore, when the engine 10 is operating,
The air filtered by the air cleaner 24 is taken into the intake passage 20, and fuel is injected from each injector 17 toward each intake port 22 at the same time as taking in the air. As a result, an air-fuel mixture is generated at the intake port 22, and the air-fuel mixture is sucked into the combustion chamber 15 with the opening of the intake valve 21 that is opened during the intake stroke.

The exhaust gas generated by the combustion in the combustion chamber 15 passes through a catalytic converter 28 provided in an exhaust passage 30 and is discharged into the atmosphere. In the present embodiment, the bypass passage 91 is provided so that the upstream side and the downstream side of the throttle valve 26 communicate with each other. An idle speed control valve (ISCV) 92 is provided in the bypass passage 91. When idling, the IS
By adjusting the opening of the CV 92, the amount of intake air flowing through the bypass passage 91 is controlled, whereby the engine speed (idling speed) during idling is controlled.

A wheel speed sensor 39 for detecting the rotational speed of each wheel (not shown) of the vehicle detects the rotational behavior of the wheel, and a brake actuator 93 for controlling the hydraulic pressure of the brake during traction control or the like is required. A control signal is output accordingly.

Next, the system configuration of the VVTs 50L and 50R will be described with reference to FIG. For convenience of explanation, FIG. 2 shows VVT50L in the left bank LS.
And the VVT 50R in the right bank RS, the cross section near the intake side camshaft 23 where the VVT 50 is disposed, and the entire control system of the VVT 50 are shown.

The control system of the VVT 50 includes a VVT 5
0, an OCV 80 for applying a driving force to the VVT 50,
An OCV based on input signals from various sensors such as a cam angle sensor 44 for detecting a cam angle signal and a cam angle sensor 44.
An ECU 70 for controlling the drive of the ECU 80 is provided.

The VVT 50 is disposed between the intake side camshaft 23 and the intake side timing pulley 27,
The intake camshaft 23 is rotatably supported between the cylinder head 12 and the bearing cap 51. An intake-side timing pulley 27 is mounted in the vicinity of the distal end of the intake-side camshaft 23 so as to be relatively rotatable, and an inner cap 52 is provided with a hollow bolt 53 and a pin 54 at the distal end of the intake-side camshaft 23. Are attached so as to be integrally rotatable.

A housing 56 having a cap 55 is attached to the intake-side timing pulley 27 by bolts 57 and pins 58 so as to be integrally rotatable. With this housing 56, the tip of the intake-side camshaft 23 and the inner The entire cap 52 is covered. Further, on the outer periphery of the intake-side timing pulley 27, a number of external teeth 27a for mounting the timing belt 35 are formed.

The intake-side camshaft 23 and the intake-side timing pulley 27 are connected by a ring gear 59 interposed between the housing 56 and the inner cap 52. The ring gear 59 has a substantially annular shape, and is housed in a space S surrounded by the intake-side timing pulley 27, the housing 56, and the inner cap 52 so as to be able to reciprocate in the axial direction of the intake-side camshaft 23. . A large number of teeth 59 are provided on the inner and outer circumferences of the ring gear 59.
a, 59b are formed.

Correspondingly, the outer periphery of the inner cap 52 and the inner periphery of the housing 56 have a number of teeth 52a,
56b are formed. These teeth 59a, 59b,
Both 52a and 56b are helical teeth whose tooth traces intersect with the axis of the intake-side camshaft 23 at a predetermined angle. That is, the teeth 52a and the teeth 59a mesh with each other, and the teeth 56b and the teeth 59b mesh with each other to form a helical spline.

The rotation of the intake-side timing pulley 27 is transmitted to the intake-side camshaft 23 via the housing 56 and the inner cap 52 due to the meshing of these. Also, each tooth 59a, 59b, 52a, 56
Since b is a helical tooth, when the ring gear 59 moves in the axial direction of the intake side camshaft 23, a twisting force is applied to the inner cap 52 and the housing 56, and the intake side camshaft 23 is attached to the intake side timing pulley 27. Move relative to

The space S has a first hydraulic chamber 60 at the distal end of the ring gear 59 and a second hydraulic chamber 61 at the proximal end of the ring gear 59 for moving the ring gear 59 in the axial direction.
have. The bearing cap 51 has a first hydraulic pressure supply hole 51a and a second hydraulic pressure supply hole 51b. The first camshaft 23 has a first
A first hydraulic supply path 62 that connects the hydraulic supply hole 51a to the first hydraulic chamber 60 and a second hydraulic supply path 63 that connects the second hydraulic supply hole 51b to the second hydraulic chamber 61 are formed. .

The lubricating oil sucked up from the oil pan 65 by the hydraulic pump 64 is supplied to each of the hydraulic pressure supply holes 51a and 51b through the oil filter 66 at a predetermined pressure. In addition, each hydraulic supply path 60, 6
In order to selectively supply the hydraulic pressure to each of the hydraulic chambers 60 and 61 through the hydraulic pressure supply hole 1, an OCV 8 is provided in each of the hydraulic pressure supply holes 51 a and 51 b.
0 is connected.

The OCV 80 is a four-port directional control valve for switching the lubricating oil flow direction by reciprocating a spool 84 in an axial direction by a plunger 83 driven by an electromagnetic actuator 81 and a coil spring 82. Then, the electromagnetic actuator 81
However, the duty is controlled to adjust the opening degree, and the magnitude of the hydraulic pressure supplied to each of the hydraulic chambers 60 and 61 is adjusted.

The casing 85 of the OCV 80 has a tank port 85t, an A port 85a, a B port 85b, and a reservoir port 85r. The tank port 85t is connected to the oil pan 65 via the hydraulic pump 64, and the A port 85a is connected to the first hydraulic supply hole 5
1a and the B port 85b are connected to the second hydraulic pressure supply hole 51b. The reservoir port 85r is connected to the oil pan 65.

The spool 84 is a cylindrical valve body.
It has four lands 84a for sealing the flow of the lubricating oil between the two ports, a passage 84b communicating between the two ports and allowing the flow of the lubricating oil, and two passages 84c.

In the VVT 50 having these configurations, OVT
When the drive of the CV 80 is controlled and the spool 84 is moved to the left in the drawing, the passage 84b
t and the A port 85a, and the first hydraulic pressure supply hole 51a
Is supplied with lubricating oil. Then, the first hydraulic pressure supply hole 51a
Is supplied to the first hydraulic chamber 60 via the first hydraulic pressure supply path 62, and the hydraulic pressure is applied to the distal end side of the ring gear 59.

At the same time, the passage 84c communicates between the B port 85b and the reservoir port 85r, and the lubricating oil in the second hydraulic chamber 61 is supplied to the second hydraulic supply passage 63, the second hydraulic supply hole 51b, and the OCV 80. Is discharged to the oil pan 65 through the B port 85b and the reservoir port 85r.

Accordingly, the ring gear 59 is moved while rotating to the base end side (right side in the drawing) by the hydraulic pressure applied to the front end side, and twist is given to the intake side camshaft 23 via the inner cap 52. . As a result, the rotational phase (displacement angle) of the intake side camshaft 23 with respect to the intake side timing pulley 27 (crankshaft 14) is changed (displaced), and the intake side camshaft 23 is shifted from the most retarded angle to the most advanced angle. To the intake valve 21
Is advanced.

The intake valve 21 whose valve opening timing has been advanced in this way is opened while the exhaust valve 31 is open, and the valve over which the intake valve 21 and the exhaust valve 31 are simultaneously opened. The lap period increases.
The movement of the ring gear 59 to the proximal end side is restricted by the ring gear 59 abutting on the intake-side timing pulley 27. When the ring gear 59 abuts on the intake-side timing pulley 27 and stops, the intake valve 21 is stopped. The valve opening timing is the earliest.

On the other hand, when the drive of the OCV 80 is controlled and the spool 84 is moved rightward in the drawing, the passage 84
b communicates between the tank port 85t and the B port 85b,
Lubricating oil is supplied to the second hydraulic pressure supply hole 51b. And
The lubricating oil supplied to the second hydraulic pressure supply hole 51b is supplied to the second hydraulic pressure chamber 61 via the second hydraulic pressure supply passage 63, and the hydraulic pressure is applied to the base end side of the ring gear 59.

At the same time, the passage 84c communicates the A port 85a with the reservoir port 85r, and the lubricating oil in the first hydraulic chamber 60 is supplied to the first hydraulic supply passage 62, the first hydraulic supply hole 51a, and the OCV 80. Is discharged to the oil pan 65 through the A port 85a and the reservoir port 85r.

Therefore, the ring gear 59 is moved while rotating to the distal end side (left side in the drawing) by the hydraulic pressure applied to the proximal end side, and the intake camshaft 23 is twisted in the opposite direction via the inner cap 52. Granted. As a result,
Intake side timing pulley 27 (crankshaft 14)
, The rotational phase (displacement angle) of the intake camshaft 23 is changed (displaced), and the intake camshaft 23 is displaced from the most advanced angle to the most retarded angle, and the valve opening timing of the intake valve 21 is changed. Is retarded.

By delaying the opening timing of the intake valve 21 in this manner, the valve overlap period during which the intake valve 21 and the exhaust valve 31 are simultaneously opened is shortened or set to zero. The ring gear 59
The ring gear 59 is moved toward the distal end side by the housing 56.
When the ring gear 59 comes into contact with the housing 56 and stops, the intake valve 21 is stopped.
Becomes the latest (the most retarded angle).

The valve timing of the intake valve 21 changed by the VVT 50 includes a cam angle signal (displacement timing signal) output from the cam angle sensor 44 and a crank angle signal (reference timing signal) output from the crank angle sensor 40. ).

That is, for example, after the displacement timing signal is input to the ECU 70, the first input crank angle signal is recognized as the reference timing signal, and the reference timing signal is input after the displacement timing signal is input. Is measured using the engine speed NE. Then, the actual displacement angle VTB of the intake-side camshaft 23 with respect to the crankshaft 14 is calculated by converting the time into a displacement angle using the relationship between the known time and the crank angle.

Next, a control system of the internal combustion engine according to this embodiment will be described with reference to a control block diagram shown in FIG. The control system of the internal combustion engine includes an electronic control unit 70 (EC
U) as a core. In the present embodiment, ECU 70 performs processing as valve timing adjustment abnormality detecting means (step S120 described later) and processing as reduced cylinder selecting means (steps S130 to S30 described later).
0).

The ECU 70 stores various control programs such as VVT control, ignition timing control, fuel injection control, traction control, and control at the time of failure, and an RO storing maps for calculating target values corresponding to various conditions.
M71. Also, the ECU 70 has a ROM 71
A CPU 72 for executing arithmetic processing based on the control program stored in the CPU 72, a RAM 73 for temporarily storing the arithmetic results of the CPU 72, data input from each sensor, and the like;
A backup RAM 74 and the like for holding various data stored in the RAM 73 when power supply is stopped are provided.

Then, the CPU 72, the ROM 71, and the RAM
73 and a backup RAM 74 include a bidirectional bus 75
And the input interface 76 and the output interface 77.

The input interface 76 includes a wheel speed sensor 39, a crank angle sensor 40, and a cylinder discrimination sensor 4.
2. The water temperature sensor 43, the left cam angle sensor 44L, the right cam angle sensor 44R, the throttle sensor 45, the intake pressure sensor 46, and the like are connected. If the signal output from each sensor is an analog signal, the signal is converted into a digital signal by an A / D converter (not shown) and then output to the bidirectional bus 75.

The output interface 77 includes an injector 17, an igniter 19, and OCVs 80L and 80.
R, ISCV 92, brake actuator 93, and other external circuits are connected.
The operation is controlled based on the calculation result of the control program executed in Step 2. The VVT 50L is controlled by driving and controlling the OCV 80L.
The control for 0R is executed independently by controlling the drive of the OCV 80R.

Next, at the time of the cylinder reduction process performed by the fuel cut accompanying the traction control, the VVT 50L, 50R in the valve timing control device VC is used.
The operation performed when the device has failed (failed) will be described.

FIG. 4 is a flowchart showing a "fuel injection timing routine" executed by the ECU 70, which is executed by interruption every predetermined crank angle in order to execute fuel injection at a suitable timing for each cylinder. . Note that steps in the flowchart corresponding to each process are denoted by “S
~ ".

When the processing shifts to this routine, first,
It is determined whether the number of reduced cylinders nfc is set (S
100). The number of reduced cylinders nfc is determined by the traction control schematically shown in the flowchart of FIG. In the traction control, the wheel slip at the time of starting the vehicle is determined based on the behavior of the wheel speed detected by the wheel speed sensor 39, and when excessive slip, that is, excessive idling, brake control (S400) is executed. And brake control (S40
If excessive slip cannot be suppressed even in step 0), the number of reduced cylinders nfc is set (S410). In the fuel injection timing routine, referring to the number of reduced cylinders nfc set in step S410 of the traction control,
The number of cylinders corresponding to the number of reduced cylinders nfc is reduced.

That is, when it is determined in step S100 that the number of reduced cylinders nfc = 0 (“N” in S100)
O "), since there is no need to reduce the number of cylinders, immediately step S1
When the routine proceeds to 10, if the current fuel injection target cylinder is a cylinder other than the fuel cut (F / C), fuel injection is performed on that cylinder. In this case, the fuel injection is always executed at any fuel injection timing for any cylinder because the number of reduced cylinders nfc = 0.

Next, if the number of reduced cylinders nfc is set to 1 or more in step S410 of the traction control ("YES" in S100), then the left bank L
It is determined whether the VVT 50L in S (also referred to as the left VVT 50L) is abnormal (S120). This determination is made as follows.

That is, the left target advance angle VTTL calculated based on the current operation state and the left actual advance value VTBL obtained from the detection value of the left cam angle sensor 44L are compared to determine the allowable value. It is determined whether there is a difference that exceeds. If it is within the allowable value, it is determined that there is no abnormality, and if it exceeds the allowable value, it is determined that there is an abnormality.

As a prerequisite for determining whether or not the left VVT 50L is abnormal, first, based on various signals input to the input interface 76, it may be determined whether or not a fail detection condition is currently satisfied. . Conditions for determining that the fail detection condition is satisfied include that the engine speed NE is equal to or higher than a predetermined speed, the cooling water temperature TH.
W is equal to or higher than a predetermined water temperature. And
If the fail detection condition is not satisfied, step S1
At 20, “NO” is determined, and if the fail detection condition is satisfied, it is determined whether the VVT 50 L is abnormal as described above.

If the left VVT 50L is not abnormal (S12)
It is determined whether the number of reduced cylinders nfc = 1 (S220). If the number of reduced cylinders nfc = 1 (S220)
"YES"), a fuel cut is set for the # 1 cylinder (S230). Next, the process proceeds to step S110 to perform fuel injection to the cylinder at the injection timing. If the # 1 cylinder is at the injection timing, the fuel injection is not performed to perform the cylinder reduction process. You. If it is another cylinder, fuel injection is performed.

In the example described above, “N
When it is determined to be "O", the case where the number of reduced cylinders nfc = 1 is used, but when the number of reduced cylinders nfc = 2, it is determined "NO" in step S220, and then whether the number of reduced cylinders nfc = 2 is satisfied. It is determined to be "YES" in the determination (S240), and the fuel cut is set for the # 1 cylinder and the # 3 cylinder (S240).
250). Next, the process proceeds to step S110 to perform fuel injection to the cylinder at the injection timing. If the # 1 cylinder or # 3 cylinder is at the injection timing, the fuel injection is not performed to reduce the fuel injection. Tube processing is performed. If it is another cylinder, fuel injection is performed.

If it is determined in step S120 that the number of reduced cylinders is nfc = 3, then if it is determined in steps S220 and S240 that the number of reduced cylinders is nfc = 3, then it is determined whether the number of reduced cylinders is nfc = 3. Is determined (S260), "YE
S ", and the fuel cut is set for the # 1, # 3 and # 5 cylinders (S270). Next, the routine proceeds to step S110, where fuel injection is performed for the cylinder at the injection timing.
When the # 3 cylinder or the # 5 cylinder is at the injection timing, the cylinder reduction processing is performed by not performing the fuel injection. If it is another cylinder, fuel injection is performed.

When it is determined "NO" in step S120, if the number of reduced cylinders nfc is 4, step S220 is performed.
"NO" in step S240 and step S260
Is determined, it is determined whether or not the number of reduced cylinders nfc = 4 (S2
80) is determined as "YES", and the fuel cut is set for the # 1, # 3, # 4 and # 5 cylinders (S290). Here, even if the fuel cut is preferentially set for the # 1 cylinder, # 3 cylinder, and # 5 cylinder belonging to the right bank RS, the number of reduced cylinders nfc remains one, so one is selected from the cylinders belonging to the left bank LS. Here, the fuel cut is set by selecting the # 4 cylinder.

Next, the routine proceeds to step S110, in which fuel injection is performed for the cylinder at the injection timing. However, if the # 1, # 3, # 4 or # 5 cylinder is at the injection timing, , The cylinder reduction process is performed by not performing the fuel injection. If it is another cylinder, fuel injection is performed.

If it is determined “NO” in step S120, and if the number of reduced cylinders nfc ≧ 5, the process proceeds to step S220.
Step S240, step S260 and step S
After the determination of “NO” at 280, the fuel cut is set for the # 1, # 3, # 4, # 5, and # 6 cylinders (S300). Here, even if the fuel cut is preferentially set for the # 1 cylinder, # 3 cylinder, and # 5 cylinder belonging to the right bank RS, the number of reduced cylinders nfc remains two, so two of the cylinders belonging to the left bank LS are selected. In this case, the fuel cut is set by selecting the # 4 cylinder and the # 6 cylinder.

Next, the routine proceeds to step S110, where fuel injection is performed for the cylinder at the injection timing. If the # 1, # 3, # 4, # 5 or # 6 cylinder is injected at the injection timing, If there is, the cylinder reduction process is performed by not performing the fuel injection. If it is another cylinder, fuel injection is performed.

As described above, when the left VVT 50L is not abnormal ("NO" in S120), that is, the VVT 50R (also referred to as the right VVT 50R) in the right bank RS is abnormal, or both the left VVT 50L and the right VVT 50R are normal. In this case, priority is given to cylinders # 1, # 3 and # 5 belonging to the right bank RS,
It is subject to cylinder reduction. If the number of reduced cylinders nfc still remains, a cylinder to be reduced is selected from the cylinders belonging to the left bank LS.

At the determination of step S120, the left VVT
If it is determined that 50L is abnormal ("Y" in S120)
ES "), it is determined whether or not the number of reduced cylinders nfc = 1 (S1).
30). If the number of reduced cylinders nfc = 1 (“Y” in S130)
ES "), a fuel cut is set for the # 2 cylinder (S140). Next, the process proceeds to step S110,
Fuel injection is performed on the cylinder at the injection timing. If the # 2 cylinder is at the injection timing, the fuel injection is not performed and the cylinder reduction process is performed. If it is another cylinder, fuel injection is performed.

In the above example, “Y
When ES is determined, the case where the number of reduced cylinders nfc is 1 is used, but when the number of reduced cylinders nfc is 2, after the determination is “NO” in step S130, the number of reduced cylinders nfc is 2 It is determined to be “YES” in the determination (S150), and the fuel cut is set for the # 2 cylinder and the # 4 cylinder (S160). Next, the process proceeds to step S110 to perform fuel injection to the cylinder at the injection timing.
If the # 2 cylinder or the # 4 cylinder is at the injection timing, the cylinder reduction process is performed by not performing the fuel injection. If it is another cylinder, fuel injection is performed.

When it is determined "YES" in step S120, if the number of reduced cylinders nfc = 3, step S130
And after it is determined "NO" in step S150,
When it is determined whether the number of reduced cylinders nfc = 3 (S170), “YE
S ", and the fuel cut is set for the # 2 cylinder, # 4 cylinder and # 6 cylinder (S180). Next, the routine proceeds to step S110, where fuel injection is performed for the cylinder at the injection timing.
When the # 4 cylinder or the # 6 cylinder is at the injection timing, the cylinder reduction process is performed by not performing the fuel injection. If it is another cylinder, fuel injection is performed.

When it is determined "YES" in step S120, if the number of reduced cylinders nfc is 4, step S13
0, "N" in step S150 and step S170.
After determining “O”, it is determined “YES” in the determination (S190) as to whether or not the number of reduced cylinders nfc = 4.
Fuel cut is set for three cylinders, # 4 cylinder, and # 6 cylinder (S200). Here, the left bank L
Even if the fuel cut is preferentially set for the # 2 cylinder, # 4 cylinder and # 6 cylinder belonging to S, the number of reduced cylinders nf
Since one c is left, 1 from the cylinder belonging to the right bank RS
In this case, the fuel cut is set by selecting the # 3 cylinder.

Next, the routine proceeds to step S110, in which fuel injection is performed for the cylinder at the injection timing. If the injection timing is for the # 2 cylinder, # 3 cylinder, # 4 cylinder or # 6 cylinder, the fuel injection is performed. , The cylinder reduction process is performed by not performing the fuel injection. If it is another cylinder, fuel injection is performed.

When it is determined “YES” in step S120, if the number of reduced cylinders nfc ≧ 5, step S13
0, “NO” in step S150, step S170, and step S190, then # 1 cylinder, #
Fuel cut is set for two cylinders, # 3 cylinder, # 4 cylinder, and # 6 cylinder (S210). Here, even if the fuel cut is preferentially set for the # 2 cylinder, # 4 cylinder and # 6 cylinder belonging to the left bank LS, the number of reduced cylinders nfc remains two, so two cylinders belonging to the right bank RS are selected. Here, the fuel cut is set by selecting the # 1 cylinder and the # 3 cylinder.

Next, the routine proceeds to step S110, in which fuel injection is performed for the cylinder at the injection timing. If the cylinder # 1, cylinder # 2, # 3, # 4, or # 6 is to be injected with the fuel at the injection timing. If there is, the cylinder reduction process is performed by not performing the fuel injection. If it is another cylinder, fuel injection is performed.

As described above, when left VVT 50L is abnormal ("YES" in S120), left bank L
The # 2, # 4, and # 6 cylinders belonging to S are prioritized and targeted for cylinder reduction. If the number of reduced cylinders nfc still remains, a cylinder to be reduced is selected from the cylinders belonging to the right bank RS.

According to the present embodiment in which the cylinder reduction process is executed in the manner described above, the following effects can be obtained. That is, as described above, when the number of cylinders to be reduced nfc is set to 1 or more by the traction control, and the number of cylinders to be reduced is instructed, in the fuel injection timing routine, if there is an abnormality in the left VVT 50L of the VVT 50, the left The # 2 cylinder, # 4 cylinder and # 6 cylinder belonging to the bank LS are preferentially targeted for cylinder reduction. If there is an abnormality in the right VVT 50R, the # 1 cylinder and # 3 belonging to the right bank RS.
Cylinders and # 5 cylinders are prioritized for cylinder reduction. Therefore, if there is an abnormality in the VVT 50, the VVT 50 is always
Since the cylinders are reduced from the cylinder side where the torque output is reduced due to the abnormality of, the torque output is not suddenly reduced during the cylinder reduction processing. Therefore, it is possible to prevent engine stall from occurring when the number of cylinders is reduced.

The present invention is not limited to the above-described embodiment, but may be implemented as follows, with a part of the configuration being appropriately changed without departing from the spirit of the invention. In the present embodiment, an example has been described in which the V-type engine 10 is employed as the internal combustion engine. However, any type of engine such as a horizontally opposed engine can be used as long as it has a plurality of banks. Further, the present invention can be applied not only to a gasoline engine but also to a diesel engine. The number of banks is not limited to two, but includes three or more.

In the present embodiment, the cylinder reduction processing accompanies traction control. However, the present invention can be applied to cylinder reduction processing in other control. In the present embodiment, the left and right VVTs 50L, 50R
Are normal, steps S220 to S30
0 is executed, and the # 1 cylinder, # 3 cylinder and # 5 cylinder belonging to the right bank RS are prioritized as cylinders to be reduced. In this way, when both the left and right VVTs 50L and 50R are normal. May prioritize any of the banks. Therefore, the # 2 cylinder, # 4 cylinder and # 6 cylinder belonging to the left bank LS may be preferentially targeted for cylinder reduction, or the priority by the bank may be stopped. , Each time the number of reduced cylinders nfc is increased, or each time a reduced cylinder is instructed, the left bank L
It is also possible to select cylinders alternately from S and the right bank RS and set them as cylinder reduction targets.

In this embodiment, the variable valve timing mechanism is a VV of the type in which the ring gear 59 moves.
Although T50 is adopted, other types of VVT (for example, vane type VVT) may be adopted. Also, OCV8
Instead of 0, another actuator may be used.

In the present embodiment, only the fuel injection in the banks LS and RS on the abnormal side is cut, but both the fuel injection and the ignition may be cut.

In the present embodiment, the ECU 70 has been described as executing a plurality of types of control as described above.
A different ECU may be configured for each control, and data communication may be performed between the ECUs via the in-vehicle LAN.

[0089]

According to the first aspect of the present invention, there is provided a variable cylinder control apparatus for an internal combustion engine having a variable valve timing mechanism, wherein the cylinder-reducing selecting means belongs to a bank adjusted by the variable valve timing mechanism which is detected as abnormal. Cylinders that have a normal torque output remain until all the abnormal cylinders are reduced. Thus, the internal combustion engine can be maintained in a desired operating state without any reduction in torque, and engine stall and the like can be prevented.

In the variable cylinder control device for an internal combustion engine with a variable valve timing mechanism according to the present invention, the internal combustion engine is used as an output engine for driving a vehicle. One or both operating conditions of the internal combustion engine. Therefore, even when the cylinder reduction processing is performed, no abnormality occurs in the running of the vehicle.

According to a third aspect of the present invention, the reduced cylinder selecting means belongs to a bank adjusted by a variable valve timing mechanism in which the number of reduced cylinders is detected as abnormal by the valve timing adjustment abnormality detecting means. If the number of cylinders is less than the number of cylinders, only the cylinders in the bank are targeted for cylinder reduction, and the variable valve timing mechanism, in which the number of cylinders to be reduced is detected as abnormal by the valve timing adjustment abnormality detecting means, is adjusted. If the number of cylinders exceeds the number of cylinders belonging to a certain bank, the exceeded number of cylinders belongs to the bank being adjusted by the variable valve timing mechanism that has been detected as not abnormal by the valve timing adjustment abnormality detecting means. Since cylinders are targeted for cylinder reduction, cylinders on the bank side having an abnormality can be preferentially targeted for cylinder reduction.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram illustrating a schematic configuration of a gasoline engine system according to an embodiment.

FIG. 2 is a schematic configuration diagram of a variable valve timing mechanism system.

FIG. 3 is a block diagram showing a control system of the ECU.

FIG. 4 is a flowchart showing a “fuel injection timing routine” executed by the ECU.

FIG. 5 is a flowchart showing “traction control” executed by the ECU.

FIG. 6 is an explanatory diagram showing the relationship between left and right banks and cylinders belonging to the banks.

[Explanation of symbols]

LS: left cylinder group (left bank), RS: right cylinder group (right bank), VC: valve timing control device, 1
0 ... V type engine, 11 ... Cylinder block, 12 ... Cylinder head, 12L ... Left cylinder head, 12R ...
Right cylinder head, 13 piston, 14 crankshaft, 15 combustion chamber, 16 spark plug, 17 injector, 18 distributor, 19 igniter, 20 intake passage, 21 intake valve, 22 intake port, 23 ... intake side camshaft, 23L ... left intake side camshaft, 23R ... right intake side camshaft,
24 air cleaner 25 surge tank 26 throttle valve 27 intake timing pulley 27a external teeth 28 catalytic converter 30 exhaust passage 31 exhaust valve 32 exhaust port 33L left exhaust camshaft , 33R: right side exhaust side cam shaft, 34: exhaust side timing pulley, 35: timing belt, 39
... wheel speed sensor, 40 ... crank angle sensor, 42 ... cylinder discrimination sensor, 43 ... water temperature sensor, 44 ... cam angle sensor,
44L: Left cam angle sensor, 44R: Right cam angle sensor, 45: Throttle sensor, 46: Intake pressure sensor,
50: Variable valve timing mechanism (VVT), 50L ...
Left VVT, 50R Right VVT, 51 Bearing cap, 51a First hydraulic supply hole, 51b Second hydraulic supply hole, 52 Inner cap, 52a Teeth, 53 Hollow bolt, 54 Pin, 55 Cap , 56 ... housing, 56b ... teeth, 57 ... bolt, 58 ... pin, 59 ... ring gear, 59a, 59b, 52a, 56b ... teeth, 60
... first hydraulic chamber, 61 ... second hydraulic chamber, 62 ... first hydraulic supply path, 63 ... second hydraulic supply path, 64 ... hydraulic pump, 64
L, 64R ... oil pump, 65 ... oil pan, 66 ...
Oil filter, 66L, 66R ... oil filter, 7
0: electronic control unit (ECU), 71: ROM, 72: C
PU, 73: RAM, 74: Backup RAM, 75
... bidirectional bus, 76 ... input interface, 77 ... output interface, 80, 80L, 80R ... oil control valve (OCV), 81 ... electromagnetic actuator, 82 ... coil spring, 83 ... plunger, 8
4 ... spool, 84a ... land, 84b, 84c ... passage, 85 ... casing, 85a ... A port, 85b ...
B port, 85r: reservoir port, 85t: tank port, 91: bypass passage, 92: idle speed control valve (ISCV), 93: brake actuator

Claims (3)

[Claims] An internal combustion engine having a variable valve timing mechanism for adjusting valve timing of one or both of an intake valve and an exhaust valve in each of a plurality of banks provided in an internal combustion engine, and performing a reduced cylinder operation according to an operating condition. An engine variable cylinder control device, comprising: a valve timing adjustment abnormality detection unit that detects whether variable adjustment of valve timing in each of the variable valve timing mechanisms is abnormal; and the valve timing adjustment abnormality detection unit. A cylinder belonging to a bank being adjusted by the variable valve timing mechanism that has been detected as being abnormal, and a cylinder-reducing selecting unit that preferentially targets the cylinder to be reduced in the cylinder-reducing operation. Variable cylinder control device for an internal combustion engine with a variable valve timing mechanism. 2. The vehicle according to claim 1, wherein the internal combustion engine is used as an output engine for driving a vehicle, and the operating condition is an operating condition of one or both of the vehicle and the internal combustion engine. A variable cylinder control device for an internal combustion engine with a variable valve timing mechanism according to claim 1. 3. The number of cylinders belonging to a bank controlled by a variable valve timing mechanism, wherein the number of cylinders to be reduced is detected as abnormal by the valve timing adjustment abnormality detecting means. If not, only the cylinders of the bank are targeted for cylinder reduction, and the number of cylinders to be reduced is determined to be the bank that is being adjusted by the variable valve timing mechanism that has been detected as abnormal by the valve timing adjustment abnormality detecting means. If the number of cylinders exceeds the number of cylinders, the number of cylinders that exceed the number of cylinders belonging to the bank that is being adjusted by the variable valve timing mechanism that is detected as not abnormal by the valve timing adjustment abnormality detection means is reduced. 3. An object for a cylinder.
A variable cylinder control device for an internal combustion engine having the variable valve timing mechanism described in the above.