JPH0261344A - Slow driving controller for internal combustion engine - Google Patents

Abstract

PURPOSE:To make constant braking torque addable to a load device irrespective of shift speed of a transmission by controlling the opening of an intake control valve installed in a passage bypassing a throttle valve according to an engine driving state and a reduction gear ration of the transmission at the time of starting the slow driving of an engine. CONSTITUTION:An intake control valve M4 is installed in an intake passage M3 bypassing a throttle valve M2 of an internal combustion engine M1, and this intake control valve M4 is opened up to the specified opening being set according to an engine driving state at time of a start of slow driving when at least the throttle valve 2 becomes fully closed, and thenit is controlled so as to be closed by degrees. In this case, there is provided with a reduction gear detecting mean M8 detecting a reduction gear ratio of a transmission M7 which transmits turning torque of the engine M1 to a load device M6. Then, opening of the intake control valve M2 being controlled by the intake control means M5 is constituted so as to be compensated by a compensating means M9 according to the detected reduction gear ratio.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention opens an intake control valve provided in an intake passage that bypasses a throttle valve during deceleration operation of an internal combustion engine to obtain a dashpot effect. The present invention relates to a deceleration operation control device for an internal combustion engine.

[Conventional Technique 1: ■In an internal combustion engine, when the throttle valve is fully closed and deceleration is started, a large negative pressure is generated in the intake passage downstream of the throttle valve, causing the fuel adhering to the intake passage wall to dissipate.・The air-fuel mixture may be drawn into the combustion chamber at once and become overrich, causing afterburn, or the volumetric efficiency may decrease and the proportion of residual gas in the combustion chamber may increase, making misfires more likely to occur. In some cases, the internal combustion engine may stop. Therefore, in order to solve this conventional problem, a valve is installed in the intake passage that bypasses the throttle valve to control the opening degree of the passage.When the internal combustion engine is decelerating, this valve is opened to secure the amount of intake air, and then By gradually closing the throttle valve, the effect is similar to that of a dashpot installed on the throttle valve.

Furthermore, when the throttle valve is fully closed and the internal combustion engine enters deceleration operation, the internal combustion engine is motored by the inertia torque on the load device side, and braking torque is applied to the load device side as an engine brake. However, when the output torque of the internal combustion engine decreases sharply at the start of deceleration operation, torsional vibration occurs in the power transmission shaft due to the deviation between the inertia torque on the load device side and the output torque of the internal combustion engine.
Furthermore, the internal combustion engine itself may vibrate around its output shaft. Conventionally, the output torque of the internal combustion engine is smoothly reduced by controlling the valve opening at the start of deceleration operation according to the operating state of the internal combustion engine before deceleration (intake pipe pressure, rotational speed, etc.). It is also considered to prevent vibrations from occurring in the internal combustion engine or its power transmission system due to a drastic decrease in output torque (Japanese Patent Laid-Open No. 55-60636)
issue.

JP-A-58-176441, JP-A-59-11904
No. 0, etc.).

[Problems to be Solved by the Invention] By the way, the output shaft of an internal combustion engine is usually provided with a transmission, and a load device is driven through the transmission. In other words, in devices such as automobiles that use an internal combustion engine as a power source, a transmission is installed between a load device such as a drive wheel and the internal combustion engine, and the gear position of the transmission is changed according to the driving state of the load device. In other words, by automatically or manually changing the reduction ratio), the load device can be driven stably.

However, in the conventional control device described above, the valve opening at the start of deceleration operation was uniformly controlled regardless of the gear position of the transmission, which caused vibrations in the internal combustion engine and power transmission system when the reduction ratio of the transmission was large. There was a problem that if the reduction ratio of the transmission was small, the engine brake would not work and the load device could not be decelerated smoothly.

That is, if the above-mentioned valve opening degree is first adapted to a state where the reduction ratio of the transmission is low, then when the reduction ratio of the transmission is high, 1 torque of H and IJ motion transmitted to the load device via the transmission will be reduced. becomes too large, causing vibrations in the internal combustion engine and power transmission system, and in automobiles, surges occur.

Otherwise, unpleasant back-and-forth vibrations of the vehicle body, such as hiccups, occur, resulting in a problem that the running stability of the vehicle is impaired.

Conversely, if the above valve opening is adapted to a state where the reduction ratio of the transmission is high, if the reduction ratio of the transmission is low, ζ
If the braking torque transmitted to the load device via the transmission is too small, the effectiveness of engine braking becomes poor, and the deceleration performance of the vehicle decreases.

Therefore, the present invention provides a device for controlling the opening and closing of an intake passage that bypasses a throttle valve during deceleration operation of an internal combustion engine.
The purpose of this invention is to enable smooth deceleration of a load device while suppressing vibrations occurring in the internal combustion engine or power transmission system, regardless of the gear position of the transmission.

[Means for solving the problem] That is, the configuration of the present invention made to achieve the above object is as follows:
As illustrated in FIG. 1, an intake control valve M4 is provided in an intake passage M3 that bypasses a throttle valve M2 of an internal combustion engine M1 and adjusts the opening degree of the intake passage M3; At the start of deceleration operation of the internal combustion engine M1, the intake control valve M5 opens the intake control valve M2 to a predetermined opening degree set according to the operating state of the internal combustion engine M1, and then gradually closes the intake control valve M5. In the deceleration operation control device for an internal combustion engine, a speed change aM transmits rotational torque of the internal combustion engine M1 to a load device M6.
a reduction ratio detection means M8 for detecting a reduction ratio of 7; and a correction means M9 for correcting the intake control valve opening controlled by the intake control flat stage M5 according to the detected reduction ratio. The gist of this paper is a deceleration operation control device for an internal combustion engine, which is characterized by:

[Operations] In the internal combustion engine deceleration operation control device of the present invention configured as described above, at the start of deceleration operation of the internal combustion engine M1,
The intake passage M4 that bypasses the throttle valve M2 is not only opened to a predetermined opening degree that is set according to the operating state of the internal combustion engine M1, but also the opening degree is corrected according to the reduction ratio of the transmission M7. be done. As a result, it becomes possible to control the braking torque transmitted to the load device M6 via the gear change IM7 at a constant level regardless of the gear position of the transmission M7 at the start of deceleration operation of the internal combustion engine, and the internal combustion engine or its power It becomes possible to smoothly decelerate the load device at a desired deceleration rate while suppressing vibrations generated in the transmission system.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

First, FIG. 2 is a schematic configuration diagram showing the configuration of an automobile internal combustion engine 2 and its peripheral devices to which the present invention is applied.

In the figure, reference numeral 4 crosses an intake pipe that sucks air through an air cleaner 6, and this intake pipe 4 includes, from upstream, an intake air temperature sensor 8 that detects the intake air temperature, and a throttle valve that controls the amount of intake air. 10, a throttle opening sensor 12 that detects the opening of the throttle valve 10, a surge tank 14 that suppresses intake pulsation, an intake pressure sensor 16 that detects the internal pressure (intake pipe pressure) P, and an internal combustion engine. 2
A fuel injection valve is provided for supplying fuel to the engine.

In addition, a bypass passage 4a that bypasses the throttle valve 10 is formed in the intake pipe 4, and this bypass passage/
la! This is an idle speed control valve (hereinafter referred to as rscv) for controlling the idle rotation speed of the internal combustion engine 2 and the vehicle deceleration during deceleration operation by adjusting the amount of intake air when the throttle valve 10 is fully closed. 20 are provided.

On the other hand, 22 is an exhaust pipe, and from the oxygen concentration in the exhaust gas, the internal combustion engine 2
The air-fuel ratio sensor 24 detects the air-fuel ratio of the fuel mixture supplied to the air-fuel mixture, and the exhaust gas. A three-way catalytic converter 26 is provided for purification.

In addition, the internal combustion engine 2 has sensors for detecting its operating state, including the above-mentioned intake temperature sensor 8, throttle opening sensor 12, intake pressure sensor 16, and air-fuel ratio sensor 24. A rotation speed sensor 30 detects the rotation speed of the internal combustion engine 2, a crank angle sensor 32 detects the fuel injection timing and ignition time to the internal combustion engine 2 based on the rotation of the distributor 2, and a crank angle sensor 32 detects the cooling water temperature of the internal combustion engine 2. Water temperature sensor 34 to detect
, and a vehicle speed sensor 35 for detecting vehicle speed. -/Fliction Control 9R is for applying high voltage from the igniter 36 to the spark plug of each cylinder at a predetermined ignition timing.

Next, the detection signals from each of the above-mentioned sensors are input manually to the electronic control circuit 40. The electronic control circuit 40 drives the fuel injection valve 18 and the igniter 36 based on the detection signals from the above-mentioned sensors to control the fuel injection amount and ignition time to the internal combustion engine 2, and also controls the opening degree of the l5CV 200 to control the internal combustion engine. This is for performing the idle rotation speed control and deceleration control of No. 2, and is configured as a logic operation circuit centered on a microcomputer, as is well known.

That is, the electronic control circuit 40 includes a central processing unit (CPU) 4 that executes various calculation processes for controlling the internal combustion engine 1 according to a preset control program.
2. A read-only memory (ROi'Vl) 44 in which control programs and initial data necessary for executing various arithmetic processes by the CPU 42 are recorded, and various data necessary for executing various arithmetic processes by the same random access memory (RAM) 46, which is temporarily read and written;
A human-powered boat 48 for manually inputting detection signals from the above-mentioned sensors, and an output boat 50 for outputting drive signals to the fuel injection valve 18, l5CV 20, igniter 36, etc. are provided, and these parts are controlled to the operating state of the internal combustion engine 2. The drive can be controlled accordingly.

In the electronic control circuit 40 configured in this way, the basic fuel injection amount and basic ignition time of the internal combustion engine 2 are determined based on the intake pipe pressure PM and the rotational speed NE detected by the intake pressure sensor 22 and the rotational speed sensor 32, respectively. determine the fuel injection amount and ignition time by correcting each calculated basic control amount based on the detection results from other sensors, and drive and control the fuel injection valve 1B and the igniter 36.
Fuel injection control and ignition timing control are repeatedly executed in the following steps, and during idling operation of the internal combustion engine 2 in which the throttle valve 10 is fully closed and the vehicle speed is 0, the rotational speed NE of the internal combustion engine 2 is set to a predetermined idle rotational speed. Idle rotation speed control is executed to control the opening degree of 15CV20 so that Deceleration control of the internal combustion engine 2 will be explained.

First, when the internal combustion engine 2 is accelerated from a steady state at time T1 and then decelerated at time T2, the acceleration/deceleration G applied to the vehicle body in the longitudinal direction changes as shown in FIG. 3 due to changes in the torque of the internal combustion engine 2. Also, when the operating state of the internal combustion engine 2 shifts from acceleration (or steady) operation to deceleration operation in this way,
If the amount of change ΔG in the acceleration/deceleration G shown in the figure is too large, large vibrations will occur in the internal combustion engine 2 and the power transmission system, causing the vehicle body to vibrate significantly in the longitudinal direction and worsening the ride comfort of the vehicle.

Therefore, in this embodiment, the amount of change Δ
G is controlled to a predetermined amount. That is, in this embodiment, the control law for l5CV20 is determined by the procedure described below, and as a result, when the vehicle starts decelerating, the internal combustion engine 2 is controlled so that the amount of change ΔG in acceleration/deceleration acting on the vehicle body always becomes a predetermined value ΔGc. The output torque is controlled.

First, the amount of change △G in acceleration/deceleration G during vehicle deceleration is calculated using the following formula (1
), it can be described as the sum of vehicle acceleration ΔG1 before deceleration and vehicle deceleration ΔG2 after deceleration.

ΔG=ΔG1+ΔG2 (1) Vehicle acceleration ΔG1 is calculated from the output torque T of the internal combustion engine 2, the reduction ratio of the transmission that transmits the rotation of the internal combustion engine 2 to the drive wheels, and the vehicle weight M using the following formula. (2) It can be written as ΔGl';T-/M (2) Vehicle deceleration ΔG2 is the motoring torque t transmitted from the drive shaft side to the internal combustion engine 2 and the reduction ratio of the transmission. From this and the vehicle weight M, it can be written as shown in the following equation (3).

ΔG2t-/M (3) Furthermore, the output torque T of the internal combustion engine 2 is determined by the intake pipe pressure PM of the internal combustion engine 2 (or the intake air ff1Q per revolution of the internal combustion engine 2).
/NE), and the motoring torque t is approximately proportional to the rotational speed NE of the internal combustion engine 2, so the above (2) and (
Equation 3) can be written as the following equations (4) and (5), respectively.

ΔG 1 : f (PM) φ K/M
...(4)ΔG2嬌g (NE)・K/
M...(5) However, f (PM) : Function of intake pipe pressure PM g (NE) : Function of rotational speed NE Next, the bypass passage in which l5CV20 is installed is narrow, and the intake air flowing inside is at the sonic speed (constant speed ), so l
Intake air 4i, Q flowing into internal combustion engine 2 via 5CV20
is proportional to l5CV2 (1 opening degree (hereinafter referred to as rscv opening degree)) S. Therefore, the output torque TiqC of the internal combustion engine 2 generated when the throttle valve 10 is closed and the internal combustion engine 2 enters deceleration operation is , as in the following equation (6) <S/
It is proportional to NE, and the acceleration generated in the vehicle body due to this generated torque, 〇isc, can be described as shown in the following equation (7).

T isc # Q/ N Ea: S/ N E
−=(6) Therefore, as mentioned above, the amount of change Δ in the vehicle acceleration speed G when the internal combustion engine 2 enters deceleration operation
In order to control G to a predetermined value △Gc, it is best to set △G15c above to the following equation (8), △G15c=Δ
G-△Gc...(8) For this, l5
It can be seen that the opening degree S of the CV 20 can be controlled as shown in the following equation (9).

5ocNE (T+ t-C/K),', S = A◆NE (f(PM)+g(NE)
-C/K)-...(9) However, C: constant (=ΔGc-M
), A: Proportionality constant, that is, l5CV20 at the start of deceleration operation
It is better to set the opening degree S to a larger value as the reduction ratio of the transmission becomes larger, the rotational speed NE of the internal combustion engine 2 becomes larger, or the intake pipe pressure PM becomes higher.

Therefore, in this embodiment, l5CV20 is controlled to the opening degree determined based on the above equation (9) until the internal combustion engine 2 enters deceleration operation, and when the throttle valve 10 is fully closed and deceleration operation begins, the vehicle acceleration/deceleration is , G changes to △Gc, and then gradually closes the I5CV20 until it reaches the reference opening Sm1n during idling operation, thereby preventing vehicle body vibration during deceleration operation. This makes it possible to obtain excellent deceleration performance.

Hereinafter, in order to control the l5CV opening degree S in this way, CP
The l5CV opening degree calculation process executed at U42 will be explained along the flowchart shown in FIG. Furthermore, this l5CV
When the l5CV opening degree S is set in the opening calculation process, the l5CV20 is drive-controlled in an unillustrated l5CV drive process so that the opening degree of the I5CV20 becomes the set l5CV opening degree S.

The l5CV opening degree calculation process is executed by the CPU 42 at predetermined time intervals (8 m5ec- in this embodiment). When the process is started, step 100 is first executed, and the intake pressure sensor 161 rotation speed sensor 30° Then, the intake pipe pressure PM, rotational speed NE, and vehicle speed SPD detected by the vehicle speed sensor 35 are read. Then, in the following step 110, the torque proportional term f (PM) in the above equation (9) is calculated based on the intake pipe pressure) Calculate the proportional term g (NE). Here, in step 110 and step 120, FIGS.
A map as shown in the figure is used. This MA represents the relationship between intake pipe pressure 1'M and output torque T, and the relationship between rotational speed NE and motoring torque t, respectively.
It is determined in advance through experiments or the like and stored in the ROM 44.

Next, in step 130, the gear position of the transmission is detected based on the rotational speed NE and vehicle speed SPD read in step 100, and a reduction ratio K is set in accordance with the detected gear position. In other words, the relationship between the rotational speed NE of the internal combustion engine 2 and the vehicle speed SPD differs depending on the gear position of the transmission, as shown in FIG. 7, and the reduction ratio of each gear position is set to a predetermined value in advance. Therefore, the gear position of the transmission is determined from the relationship between the rotational speed NE and the vehicle speed SPD, and the reduction ratio K is set in accordance with the gear position. Once the reduction ratio K of the transmission is set in this way, the process proceeds to step 140, where the reduction ratio is calculated from the preset constant C (9).
) is calculated, and the process proceeds to step 150, where the l5CV opening degree S' is calculated using the above equation (9).

Next, in step 160, the currently set l5CV
Opening degree S (1!II, actual I SCV opening degree at the moment)
is multiplied by a predetermined value B smaller than 1 (for example, 0.95'), and the value is calculated as the l5CV opening degree S, followed by step 17.
0, it is determined whether the (g difference (S-5") between the set l5CV opening S and the rscv opening S obtained in step 150 is a negative value. Then, if this deviation is negative If it is determined that I S
Opening degree S' obtained in step 150 above by CV opening degree
After setting, the process proceeds to step 190, and if not, the process directly proceeds to step 190.

In steps 160 to 180, the rscv opening S obtained in step 150 is compared in magnitude with the value obtained by multiplying the current l5CV opening S by a predetermined value B, and the larger one is set as the l5CV opening. I am trying to set it as S.

In other words, during acceleration operation or constant current operation of the internal combustion engine 2,
rsc is set according to the above formula (9) according to the operating state.
The v opening S opening becomes a value greater than the current l5CV opening S, but when the internal combustion engine 2 enters deceleration operation, the current rscv opening S opens as the intake pipe pressure PM and rotation speed NE decrease. The l5CV opening degree S becomes smaller than the throttle valve 10.
During sudden deceleration when the rscv is fully closed, the l5CV opening S' becomes significantly smaller than the previously determined rscv opening, and this value S'
If the output torque of the internal combustion engine is used as is, the output torque of the internal combustion engine will suddenly decrease, so here, by suppressing the rate of decrease of the l5CV opening degree S after the start of deceleration operation to a predetermined value B, l5CV20 is gradually closed, and thereby the internal combustion engine This prevents the output torque from decreasing suddenly.

Next, in step 190, I
Determine whether the SCV opening degree has fallen below the reference opening degree S min during idling operation. If S - S min, the process moves to step 200 and after setting the SCV opening degree S opening degree m1n, the process is once terminated; otherwise, the process is once terminated. In other words, this step 1
90 and step 200, the l5CV opening degree S during deceleration operation is determined to prevent the internal combustion engine 2 from closing too much during deceleration operation and causing the internal combustion engine 2 to stop when the internal combustion engine 2 enters idling operation. The minimum opening degree is secured as the reference opening degree Sm1n during idling operation.

In the internal combustion engine control device of this embodiment configured as described above, for example, as shown in FIG.
When the torque valve 10 is opened and the internal combustion engine 2 shifts from idling operation to acceleration operation, the torque proportional term f (PM) and the rotation speed proportional term g (NE) increase as the intake pipe pressure PM and rotation speed NE increase. , l5CV20 is the above (9)
■SC■Opening degree S calculated using the formula is controlled.

Therefore, when the internal combustion engine 2 starts decelerating operation, l5
The CV opening degree S can be precisely controlled. In addition, the l5CV opening degree at this time is set to a larger value according to the reduction ratio K of the transmission, as the reduction ratio K becomes larger, according to the above equation (9), so the vehicle body acceleration/deceleration at the start of deceleration operation is It is possible to control the amount of change in G ΔG to be constant regardless of the reduction ratio of the transmission, which prevents vehicle body vibration from occurring due to differences in the reduction ratio of the transmission, or deterioration of the deceleration performance of the vehicle. Nor.

Next, during this acceleration operation, the throttle valve 10 is fully closed, and after the internal combustion engine 2 shifts to deceleration operation, the intake pipe pressure P
M, torque proportional term f (PM
), the rotational speed proportional term g(NE) suddenly decreases, and the above (
9) The l5CV opening degree S' calculated using formula also decreases rapidly, but at this time, the l5CV20 is controlled to the l5CV opening degree S obtained by multiplying the rscv opening degree S by the opening constant value B every 8 m5ec. be done. As a result, l5CV after the start of deceleration operation
The opening degree S is the standard opening degree during idling operation S +n i n
This makes it possible to suppress a sudden decrease in the intake air amount and smoothly reduce the vehicle speed.

In this way, according to this embodiment, the IS at the start of deceleration operation is
Control can be performed so that optimum deceleration characteristics are always obtained depending on the CV opening degree, the operating state of the internal combustion engine 2, and the gear ratio of the transmission, and vibrations occurring in the internal combustion engine or power transmission system are suppressed. This makes it possible to prevent unpleasant vibrations such as surges and jerks from occurring in the vehicle body. In addition, since the vibration of the internal combustion engine (rotational vibration around the output shaft) can be suppressed, the mounting system of the internal combustion engine 2 can be made softer and the internal combustion engine 2 can be
The vibration and noise caused by the operation of the machine can be reduced.

Here, in the above embodiment, at the start of deceleration driving, l5
Although the configuration was configured to control the CV opening degree S, the l5CV opening degree S was determined and the l5CV20 was controlled so that the deceleration ΔG2 of the vehicle body at the start of deceleration driving shown in FIG. 3 became a predetermined value. The same effect as above can be obtained.

In this case, △G15c described by the above equation (7) is changed to the following equation (
8) Since the slippage is good as shown in ', ΔG15c=
ΔG−ΔG c −(8)′15The arithmetic expression for calculating the CV opening degree S is as shown in the following equation (9)′.

5OcNE (t -C/K),', 5=A-NE (g(NE) -C/K)
...(9)' [Effects of the Invention] As detailed above, according to the deceleration operation control device for an internal combustion engine of the present invention, at the start of deceleration operation of the internal combustion engine, the intake passage that bypasses the throttle valve is It is now possible to control according to the operating state of M1 and the reduction ratio of the transmission, and apply a constant braking torque to the brake system regardless of the gear position of the transmission, and to apply a constant braking torque to the internal combustion engine or its power transmission system. It becomes possible to smoothly decelerate the load device at a desired deceleration rate while suppressing generated vibrations. In addition, it is possible to suppress the vibrations of the internal combustion engine that occur during deceleration operation, that is, the rotational vibrations around the output shaft of the internal combustion engine, so the mounting system of the internal combustion engine can be made softer, which allows the internal combustion engine to reduce vibrations that occur due to the combustion of the fuel mixture. It also becomes possible to reduce vibration and noise.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a schematic configuration diagram showing an internal combustion engine for an automobile and its peripheral equipment, and FIG. A diagram showing the acceleration/deceleration G, FIG. 11 is a flowchart showing the ISCV opening calculation process executed by the electronic control circuit, and FIG. 5 is a map used to calculate the torque proportional term f (PM). Figure 6 is a diagram representing the map used to calculate the rotational speed proportional term g (NE), and Figure 7 is a diagram representing the map used to calculate the rotational speed proportional term g (NE). FIG. 8 is a diagram showing the relationship between the rotational speed NE and the vehicle speed SPD, and a time chart explaining the operation of the embodiment. Ml, 2... Internal combustion engine M2.10... Throttle valve M3... Intake passage (4a... Bypass passage) M4
...Intake control valve (20...ISCV) M5...
Intake control means M6...Load device M7...Transmission
M8... Reduction ratio detection means M9... Correction means 16-
...Intake pressure sensor 30...Rotational speed sensor 1no 35.
...Vehicle speed sensor 40...Electronic control circuit agent Tsutomu Sadatsu (and 2 others), patent attorney Go to Figure 1 Figure 3 Figure 5 Figure P ■ Figure 6 E

Claims (1)

[Scope of Claims] An intake control valve that is provided in an intake passage that bypasses a throttle valve of an internal combustion engine and adjusts the opening degree of the intake passage; , an intake control means for opening the intake control valve to a predetermined opening degree set according to the operating state of the internal combustion engine, and then gradually closing the intake control valve; a reduction ratio detection means for detecting a reduction ratio of a transmission that transmits rotational torque of the transmission to a load device; and a correction means for correcting an intake control valve opening controlled by the intake control means in accordance with the detected reduction ratio. A deceleration operation control device for an internal combustion engine, comprising: