JP2014185611A - Control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of an internal combustion engine capable of early warming-up of a catalyst without increasing noise.SOLUTION: A control device of an internal combustion engine includes a power generator generating power by using power of an internal combustion engine, a catalyst for purifying an exhaust gas of the internal combustion engine, and a warming-up determination control portion for determining whether warming-up of the catalyst is necessary or not in starting an intake amount regulation valve for regulating an amount of intake air supplied to the internal combustion engine, and the internal combustion engine. The control device further includes a power generation amount regulation control portion for increasing a power generation amount of the generator when the necessity of the warming-up of the catalyst is determined, and a regulation valve control portion for controlling the intake amount regulation valve so that a rotating speed of the engine is kept at a target rotating speed when the power generation amount of the generator is increased.

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine that warms the catalyst to a predetermined temperature when the catalyst is in a cold state.

2. Description of the Related Art Conventionally, as an internal combustion engine control device, an exhaust pipe provided with a catalyst for purifying exhaust gas is known.
Since the catalyst purification effect is not exhibited until the temperature of the catalyst reaches a predetermined temperature, for example, immediately after the internal combustion engine is started, exhaust gas is not purified.
Therefore, what is disclosed in Patent Document 1 below is a control for warming up the catalyst, and after the ignition retarding process for delaying the ignition timing in the spark plug from the previous state is started by the ignition means, the catalyst is fed into the combustion chamber. A control device for an internal combustion engine having the ignition means and the intake means so as to start an intake air amount increase process for increasing the amount of air is disclosed.
According to this, the so-called afterburning occurs due to the ignition timing delay, and the catalyst is warmed up early.

JP 2004-124826 A

By the way, in the control apparatus of the conventional internal combustion engine, what is disclosed in the above-mentioned Patent Document 1 is that in order to increase the amount of air sent to the catalyst for the purpose of early warming up of the catalyst, The target rotational speed of the internal combustion engine is set high, and the rotational speed of the internal combustion engine becomes higher than that in the case where the catalyst warm-up control is not executed, and there is a disadvantage that noise increases.
Further, in a conventional control device for an internal combustion engine, there is a technique for reducing power consumption by controlling a fuel pump by a PWM method using a controller in order to improve fuel consumption.
Although there is a technique (for example, the above-mentioned Patent Document 1) of increasing the rotational speed of the internal combustion engine for the purpose of early catalyst activation immediately after the start of the internal combustion engine, the engine noise increases when the rotational speed of the internal combustion engine is increased. Since there is a problem with noise, there is a demand for dealing with an engine load rather than a rotation.

  An object of the present invention is to provide a control device for an internal combustion engine that can perform early warm-up of a catalyst without increasing noise.

  Therefore, in order to eliminate the above-described disadvantages, the present invention provides a generator that generates electric power using the power of the internal combustion engine, a catalyst for purifying exhaust gas of the internal combustion engine, and an intake air amount supplied to the internal combustion engine. An internal combustion engine control device comprising: an intake air amount adjustment valve that adjusts the warming-up amount; and a warm-up determination control unit that determines whether or not the catalyst needs to be warmed up when the internal combustion engine is started. When it is determined that it is necessary, the power generation amount adjustment control unit that increases the power generation amount of the generator, and when the power generation amount of the generator is increased, the rotational speed of the internal combustion engine becomes the target rotational speed, And an adjustment valve control unit that controls the intake air amount adjustment valve.

According to the present invention, when the catalyst needs to be warmed up at the time of starting, the power generation amount adjustment control unit increases the power generation amount of the generator connected to the internal combustion engine and applies a load to the internal combustion engine.
As a result, the rotational speed of the internal combustion engine decreases.
At this time, the adjustment valve control unit increases the opening of the intake air amount adjustment valve so that the rotation speed of the internal combustion engine becomes the target rotation speed.
With the above configuration, the rotational speed of the internal combustion engine is maintained at the target rotational speed, the increase in noise can be prevented, and the intake air amount can be increased. Sent.
Therefore, the catalyst is warmed up early without increasing noise.

FIG. 1 is a control flowchart of the control device for the internal combustion engine. (Example) FIG. 2 is a system configuration diagram of the control device for the internal combustion engine. (Example) FIG. 3 is a time chart of the control device for the internal combustion engine. (Example) FIG. 4 is a graph showing the difference between the technique of the present invention and the conventional technique in the relationship between the rotational speed of the internal combustion engine and time. (Example)

  Embodiments of the present invention will be described below in detail with reference to the drawings.

1 to 4 show an embodiment of the present invention.
In FIG. 2, reference numeral 1 denotes an internal combustion engine control device.
The control device 1 for the internal combustion engine includes a control means 2 that functions as a central processing unit, and a catalyst (not shown) for purifying the exhaust gas of the internal combustion engine.
Then, on the input side of the control means 2, an accelerator pedal sensor 3 that detects a depression state of an accelerator pedal (not shown) (also referred to as “operation state”), and a depression state of a brake pedal (not shown) (“operation state”) In other words, a brake pedal sensor 4 that detects the operation state of a side brake (not shown), and a crank angle sensor 6 that detects the rotational speed of the internal combustion engine are connected.
Further, on the output side of the control means 2, a generator 7 for generating electric power using the power of the internal combustion engine, an intake air amount adjusting valve 8 comprising a throttle valve for adjusting the intake air amount supplied to the internal combustion engine, A fuel pump 9 for sending the fuel in the fuel tank to the internal combustion engine and an air conditioner fan 10 are connected.
The control means 2 includes a warm-up determination control unit 11 that determines whether or not the catalyst needs to be warmed up when the internal combustion engine is started.

The control means 2 of the control device 1 for the internal combustion engine includes a power generation amount adjustment control unit 12 that increases the power generation amount of the generator 7 when it is determined that the catalyst needs to be warmed up, and the generator 7. And an adjusting valve control unit 13 for controlling the intake air amount adjusting valve 8 so that the rotational speed of the internal combustion engine becomes a target rotational speed when the amount of power generation is increased.
Specifically, as shown in FIG. 2, the control means 2 includes an idling stop control unit 14, the power generation amount adjustment control unit 12, the adjustment valve control unit 13, the warm-up determination control unit 11, and the like. A timer 15 and a memory 16 are provided.

The control means 2 determines whether or not the catalyst needs to be warmed up based on whether or not the idling stop control unit 14 has an idling stop history.
When determining whether the catalyst needs to be warmed up, attach a temperature sensor directly to the catalyst and determine whether the catalyst needs to be warmed up based on the detection signal of the attached temperature sensor. Is also possible.
At this time, the idling stop history of the idling stop control unit 14 causes the internal combustion engine to stop when the idling stop control unit 14 satisfies a preset idling stop condition, and this situation is stored in the memory 16. I remember it.
The idling stop condition is, for example, that the vehicle speed is equal to or lower than a set value, the brake pedal is depressed, the brake is in operation, and the catalyst has been warmed up. It ’s fine.
Then, the control means 2 of the control device 1 of the internal combustion engine confirms the idling stop history of the idling stop control unit 14, and determines that the catalyst has already been warmed up when there is an idling stop history, On the contrary, when there is no idling stop history, it is determined that the catalyst is not warmed up.

When determining the starting state of the internal combustion engine, the control means 2 detects the rotational speed of the internal combustion engine based on an output value that is a detection signal from the crank angle sensor 6, and changes the rotational speed of the internal combustion engine. A measure to confirm is adopted.
However, in addition to the measures described above, it is also possible to detect the internal state of the accelerator pedal by the detection signal from the accelerator pedal sensor 3 or the release state of the brake pedal by the detection signal from the brake pedal sensor 4. It is possible to determine the starting state of the engine.
The control means 2 also determines whether or not the rotational speed of the internal combustion engine has reached a preset target rotational speed based on a detection signal from the crank angle sensor 6.

The control means 2 of the control device 1 for the internal combustion engine controls the power generation amount adjustment control unit 12 to increase the power generation amount of the generator 7 when it is determined that the catalyst needs to be warmed up. .
Actually, the control means 2 switches the electric load from the off state to the on state, thereby increasing the power consumption.
At this time, as an electrical load, there is a measure for driving the fuel pump 9 or the fan 10 for an air conditioner.
When the power generation amount of the generator 7 is increased by the power generation amount adjustment control unit 12, the rotational speed of the internal combustion engine is suppressed by an electric load. Therefore, the rotational speed of the internal combustion engine is indicated by a solid line in FIG. As described above, the intake air amount adjusting valve 8 is controlled by the adjusting valve control unit 13 so that the target rotational speed is set to a low state in advance.

As a result, when the catalyst needs to be warmed up at the start, the power generation amount adjustment control unit 12 increases the power generation amount of the generator 7 connected to the internal combustion engine and applies an electric load to the internal combustion engine. .
As a result, the rotational speed of the internal combustion engine decreases.
At this time, the adjustment valve control unit 13 increases the opening of the intake air amount adjustment valve 8 so that the rotation speed of the internal combustion engine becomes the target rotation speed.
According to the configuration described above, the rotational speed of the internal combustion engine is maintained at the target rotational speed, an increase in noise can be prevented, and the intake air amount can be increased. Many are sent to the catalyst.
Therefore, the catalyst is warmed up early without increasing noise.

In addition, the adjustment valve control unit 13 is configured to control the intake air amount adjustment valve 8 to increase the intake air amount after the power generation amount adjustment control unit 12 increases the power generation amount.
That is, when the power generation amount adjustment control unit 12 does not increase the power generation amount, the adjustment valve control unit 13 does not control the intake amount adjustment valve 8 to increase the intake amount.
Thus, if configured as described above, the intake air amount adjusting valve 8 is controlled before the amount of power generation is increased, and the rotational speed of the internal combustion engine can be prevented from exceeding the target rotational speed, thereby preventing an increase in noise. it can.

Further, the power generation amount adjustment control unit 12 is configured to gradually increase a duty ratio for controlling the fuel pump 9 that supplies fuel to the internal combustion engine to increase the power generation amount.
That is, the duty ratio for controlling the fuel pump 9 is adjusted so as to gradually increase from 80% to 90%, for example.
With this configuration, the power consumption of the fuel pump 9 is gradually increased, so that the rotational speed of the internal combustion engine does not drop suddenly, and engine stall can be prevented.

Furthermore, the control means 2 of the control device 1 for the internal combustion engine determines whether or not the elapsed time from the start measured by the timer 15 is equal to or longer than a set time as shown in FIG.
The control means 2 of the control device 1 for the internal combustion engine considers that the catalyst has been warmed up when the elapsed time from the start is equal to or longer than the set time.
Thereby, by setting the set time, the control time by the control means 2 of the control device 1 of the internal combustion engine is not made long, and the deterioration of exhaust gas and the deterioration of fuel consumption are appropriately avoided.
In addition, when starting control measured by the timer 15 is started in the control means 2 of the control device 1 of the internal combustion engine, conventionally, as shown by a one-dot chain line in FIG. The fuel pump 9 is controlled only at a duty ratio of 100%.
On the other hand, in the present invention, the fuel pump 9 is controlled at a duty ratio of 100% until the elapsed time becomes equal to or longer than the set time after the start control measured by the timer 15 is started.

  Next, a description will be given along the control flowchart of the control device 1 for the internal combustion engine shown in FIG.

When the control program of the control device 1 for the internal combustion engine is started (101), the process proceeds to the determination (102) as to whether or not the catalyst needs to be warmed up.
In this determination (102), the control means 2 determines whether or not the catalyst needs to be warmed up based on the presence or absence of the idling stop history by the idling stop control unit 14.
Then, the control means 2 confirms the idling stop history of the idling stop control unit 14, determines that the catalyst has already been warmed up when there is a history, and conversely, if there is no history, the catalyst Judge that it is before warm-up.
In the determination (102) of whether or not it is necessary to warm up the catalyst, if the determination (102) is NO, the process proceeds to a return (107) described later.
If the determination whether the catalyst needs to be warmed up (102) is YES, the process proceeds to determination (103) as to whether the internal combustion engine has been started.
In this determination (103), the control means 2 detects the rotational speed of the internal combustion engine based on the output value that is the detection signal from the crank angle sensor 6, and confirms the fluctuation of the rotational speed of the internal combustion engine. Further, the start state of the internal combustion engine is determined based on a measure for detecting the depression state of the accelerator pedal based on the detection signal from the accelerator pedal sensor 3 or the release state of the brake pedal based on the detection signal from the brake pedal sensor 4. .
In the determination (103) of whether or not the internal combustion engine is started, if the determination (103) is NO, the process proceeds to return (107).
If the determination (103) on whether or not the internal combustion engine has been started is YES, the routine proceeds to determination (104) on whether or not the rotational speed of the internal combustion engine has reached the target rotational speed.
In this determination (104), the control means 2 determines whether or not the rotational speed of the internal combustion engine has reached a preset target rotational speed based on the detection signal from the crank angle sensor 6.
Then, in the determination (104) of whether or not the rotational speed of the internal combustion engine has reached the target rotational speed, if the determination (104) is YES, the routine proceeds to return (107).
If the determination (104) of whether or not the rotational speed of the internal combustion engine has reached the target rotational speed is NO, the routine proceeds to processing (105) for increasing or decreasing the power generation amount of the generator 7.
In this process (105), the power generation amount of the power generator 7 is controlled by the power generation amount adjustment control unit 12. In practice, the control means 2 switches the electrical load from the off state to the on state. , Increase power consumption.
At this time, when the power generation amount of the generator 7 is increased by the power generation amount adjustment control unit 12, the rotational speed of the internal combustion engine is suppressed by an increase in the electric load, so that the rotational speed of the internal combustion engine is lowered. The intake valve 8 is controlled by the adjusting valve control unit 13 so that the target rotational speed is set in advance.
After the process (105) for increasing or decreasing the power generation amount of the generator 7 described above, the routine proceeds to a determination (106) as to whether or not the elapsed time since the start of the internal combustion engine is equal to or longer than a set time.
In this determination (106), it is determined by the control means 2 of the control device 1 of the internal combustion engine whether or not the elapsed time from the start measured by the timer 15 is equal to or longer than a set time as shown in FIG. When the elapsed time from the start is equal to or longer than the set time, the catalyst is considered warmed up.
In the determination (106) of whether or not the elapsed time since the start is equal to or longer than the set time, if this determination (106) is NO, whether the rotational speed of the internal combustion engine has reached the target rotational speed. It returns to judgment (104) of no.
If the judgment (106) on whether or not the elapsed time from the start is equal to or longer than the set time is YES, the routine proceeds to return (107).

  The present invention is not limited to the above-described embodiments, and various application modifications can be made.

For example, in the embodiment of the present invention, the internal combustion engine control apparatus is configured to increase the power generation amount of the generator by turning on the electrical load when the catalyst needs to be warmed up. It is also possible to adopt a special configuration that is adopted for a vehicle that is performing power generation suppression control.
That is, a vehicle that performs power generation prohibition and / or power generation suppression control after starting is aimed at improving fuel efficiency.
For this reason, when the catalyst needs to be warmed up, that is, when the condition for determining the catalyst activity is satisfied, normal power generation is performed to increase the electrical load and promote early activation of the catalyst, thereby reducing harmful exhaust gas. It can also be a policy.

DESCRIPTION OF SYMBOLS 1 Control apparatus of an internal combustion engine 2 Control means 3 Accelerator pedal sensor 4 Brake pedal sensor 5 Side brake sensor 6 Crank angle sensor 7 Generator 8 Intake amount adjustment valve 9 Fuel pump 10 Air conditioner fan 11 Warm-up determination control part 12 Electric power generation amount Adjustment control unit 13 Adjustment valve control unit 14 Idling stop control unit 15 Timer 16 Memory

Claims (3)

  A generator that generates electric power using the power of the internal combustion engine, a catalyst for purifying exhaust gas of the internal combustion engine, an intake air amount adjustment valve that adjusts an intake air amount supplied to the internal combustion engine, and at the start of the internal combustion engine And a warm-up determination control unit that determines whether or not the catalyst needs to be warmed up. When it is determined that the catalyst needs to be warmed up, the power generation amount of the generator is determined. A power generation amount adjustment control unit for increasing, and an adjustment valve control unit for controlling the intake air amount adjustment valve so that the rotation speed of the internal combustion engine becomes a target rotation speed when the power generation amount of the generator is increased. A control apparatus for an internal combustion engine, characterized by comprising:   2. The control apparatus for an internal combustion engine according to claim 1, wherein the adjustment valve control unit controls the intake air amount adjustment valve to increase the intake air amount after the power generation amount adjustment control unit increases the power generation amount. .   3. The internal combustion engine according to claim 1, wherein the power generation amount adjustment control unit gradually increases a duty ratio for controlling a fuel pump that supplies fuel to the internal combustion engine to increase the power generation amount. Engine control device.

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