JPH0388928A - Control device for air suction amount of engine - Google Patents

Abstract

PURPOSE:To prevent temporary blowing-up by giving a different value to the increment of the suction air amount during decelerative operation in the case with downward shift, from the value in the otherwise case, suppressing quick drop of the engine revolving speed even during downward shift, and lowering the revolving speed mildly. CONSTITUTION:While an incremental amount control means 36 is performing incremental control of the suction air amount upon making initial setting of a dashpot amount to a specified value X, a shift sensing means 29 senses downward shift to No.1 gearing position from No.2 gearing position where the gear ratio is put onto the deceleration side, and the dashpot amount is set to zero compulsorily, and the increment of the suction air amount is restricted small by the use of a restricting means 37. During decelerative operation, i.e., downward shift is made by an automatic transmission according to the deceleration, and the dashpot amount after downward shift into the No.1 gearing position is set compulsorily to zero in case there is downward shift to the No.1 from No.2 position when the dashpot amount is damped. Thus the engine revolving speed lowers smoothly without temporary blowing-up even at the time of downward shift into the No.1 position.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in an engine intake air amount control device that controls the intake air amount of an engine when transitioning to an idling operating state.

(Prior Art) Conventionally, as an intake air amount control device for this type of engine, as disclosed in, for example, Japanese Unexamined Patent Publication No. 55-60636, a passage bypassing a throttle valve is provided in the intake passage of the engine. When the engine transitions to idling operation due to deceleration, the amount of intake air flowing through the bypass passage is increased, suppressing the sudden drop in engine speed that accompanies deceleration, reducing shock and effectively preventing engine stalling. There are known methods to prevent this.

(Problem to be Solved by the Invention) However, when the engine is in deceleration operation, a downshift may be performed in the transmission connected to the engine. For this reason, in the conventional system described above, the intake air amount increase control and downshifting may overlap during deceleration operation.
As a result, the engine speed does not only gradually decrease, but increases, resulting in a shortcoming that the engine speed temporarily increases.

The present invention has been made in view of the above, and its purpose is to temporarily reduce the rotational speed even when there is a downshift in the transmission during intake air volume increase control during deceleration operation. The advantage is that the engine speed can be gradually lowered without causing engine racing.

(Means for Solving the Problems) In order to achieve the above object, the present invention sets the increase in the amount of intake air during deceleration operation to a value that differs between when there is a downshift and when there is no downshift. shall be.

That is, the specific solution of the present invention, as shown in FIG. 1, includes an air amount adjusting means 30 that adjusts the intake air amount of the engine, a deceleration detecting means 35 that detects when the engine is decelerating, An intake air amount control device for an engine, comprising: an increase control means 36 that controls the air amount adjustment means 30 to increase the amount of intake air of the engine so as to reduce shock during deceleration operation detected by the deceleration detection means 35. Assuming that. Then, while the intake air amount is being increased by the two speed change detection means for detecting the speed change state of the transmission connected to the engine and the intake air amount control means 36, the speed change detection means 29 changes the speed ratio to the deceleration side. A restricting means 37 is provided for restricting the increase in intake air amount to a small amount when downshifting is detected.

(Function) With the above configuration, in the present invention, the intake air amount is basically increased by a predetermined amount by the increase control means 36 during deceleration operation of the engine, so that a sudden drop in engine speed is suppressed and a shock is prevented. reduced.

At that time, if there is a downshift in the transmission,
The increase in the amount of intake air is limited by the limiting means 37 to a smaller amount than in the case without downshifting, and as a result, the extent to which the sudden drop in engine speed is suppressed is moderate, so that the engine speed does not temporarily increase. This effectively prevents temporary spikes in rotational speed.

(Effects of the Invention) As explained above, according to the engine intake air amount control device of the present invention, even if there is a downshift while the intake air amount is increased during deceleration operation, the engine speed Since the degree to which the sudden decline in numbers can be suppressed can be adjusted appropriately,
The engine speed can be gradually lowered, and a temporary spike in the engine speed can be prevented.

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

FIG. 2 shows the overall configuration of an engine intake air amount control device according to the present invention. In the figure, 1 is an engine, 2 is a combustion chamber whose volume is variable by a piston 4 slidably inserted into a cylinder 3 of the engine 1, and 5 is connected to the atmosphere at one end via an air cleaner 6. The other end is the combustion chamber 2
An intake passage 7 communicates with the combustion chamber 2 to supply intake air to the engine 1, and an exhaust passage 7 communicates with the combustion chamber 2 at one end and communicates with the atmosphere to discharge exhaust gas. A throttle valve 8 for controlling the amount of intake air, and a fuel injection valve 9 for injecting fuel into the engine 1 downstream of the throttle valve 8 are disposed in the middle of the intake passage 5. In addition, the intake passage 5
An intake valve 10 is disposed at the opening of the exhaust passage 7 to the combustion chamber 2, and an exhaust valve 11 is disposed at the opening of the exhaust passage 7 to the combustion chamber 2.

Further, upstream and downstream of the throttle valve 8 of the intake passage 5,
A bypass passage 15 that bypasses the throttle valve 8 is provided, and a bypass passage 1 is provided in the middle of the bypass passage 15.
A control valve 16 for increasing or decreasing the passage area of the bypass passage 15 is disposed, and by adjusting the passage area of the bypass passage 15 by the control valve 16, the amount of bypass air flowing through the bypass passage 15 is increased or decreased, thereby increasing or decreasing the amount of bypass air flowing through the bypass passage 15. An air amount adjusting means 30 is configured to adjust the amount of intake air.

Then, during deceleration operation of engine 1, the amount of bypass air is increased (hereinafter referred to as dashpot).
This will prevent a sudden drop in engine speed.

Furthermore, 17 is an automatic transmission connected to the output shaft 1a of the engine 1. The automatic transmission 17 has internally the following:
A torque converter 18 having a pump 18a, a stator 18b, and a turbine 18c; for example, a four-speed forward drive connected to an output shaft (turbine shaft 18d) of the converter 18;
A transmission gear mechanism 19 with one reverse gear is provided.

In addition, 20 is an air flow sensor that measures the amount of intake air on the upstream side of the throttle valve 8 in the intake passage 5 of the engine 1;
1 is an intake air temperature sensor that detects the intake air temperature near the air flow sensor 20; 22 is an opening sensor that detects the opening of the throttle valve 8; 23 is an idle switch that detects when the throttle valve 8 is fully closed; A crank angle sensor 25 detects the crank angle of the engine 1, a cooling water temperature sensor 25 detects the engine cooling water temperature, and 26 detects the engine rotation speed from the operating state of a distributor that distributes high voltage to the cylinders in the explosion stroke. It is a rotation speed sensor. Therefore, the detection signals of each of the sensors 20 to 26 are internally
It is input to an engine controller 27 equipped with a PU, etc., and the controller 27 controls the passage area of the bypass passage 15, that is, the amount of bypass air, using the control valve 16.

In addition, in the figure, reference numeral 28 denotes an automatic transmission controller that controls the automatic transmission 17, and the controller 28 controls a plurality of electromagnetic valves of a hydraulic control circuit (not shown) included in the transmission mechanism 19. It has a function of controlling the SOL and automatically changing gears according to the vehicle speed and the opening degree of the throttle valve 8. The controller 28 has a function as a speed change detection means 29 that self-detects the speed change state of the speed change mechanism 19 through internal speed change control, and also has a function of transmitting the speed change state signal to the engine controller 27. Be prepared.

Next, the control valve 1 by the engine controller 27 is
The operation control of No. 6 will be explained based on the control flow shown in FIG.

After the engine starts and the engine speed, idle switch state, and shift state signal from the automatic transmission controller 28 are read in step S1, the dashpot execution enable flag PIDP (originally PIDP-0) is read in step S2.
Initially, it is PIDP-0, so in steps S3 and S4, the engine speed Ne and the state of the idle switch 23 are determined, respectively, and Ne
<A (A is the set rotational speed to start the dashpot), and if the idle switch 23 is turned ON for the first time, it is determined that the throttle valve opening is fully open and deceleration operation is in progress. In step S5, the dashpot executable flag FIDP-1 is set.

After that, the engine speed Ne is determined again in step S6, and when A>Ne due to the decrease in the engine speed, the shift state signal from the automatic transmission controller 28 changes from the second speed to the first speed in step S7. (shift execution flag FAT-0)
only, the dashpot execution flag FD is set in step S8.
After setting P to FDP-1, the dashpot amount (increase in the amount of air flowing through the bypass passage 15) is determined in step S9.
is initially set to a predetermined value X.

After that, the idle switch 23 is turned ON in step SIo.
Only when the state is maintained and the throttle valve opening is fully open, if the shift execution flag FAT-0 is not in the shift state in step S11, the dashpot amount is slightly attenuated from the initial value X in step SI2 ffi K I DGDP to MW
Then, in step S+3, dashpot ff1x becomes x-
After repeating step 5IO-S+3 until the value becomes 0, the dashpot executable flag PIDP is set in step SI4.
and dashpot execution flag FDP to FIDP-0,
The process returns to FDP-0 and returns to step S1.

On the other hand, in step S9 above, the dashpot amount is xIiii
! Even if the idle switch 23 is OFF in step SIO and the throttle valve opening is no longer fully closed, or the shift execution flag FAT-1 is set and the transmission 1
When the downshift from the second speed to the first speed is performed in step S7, the dashpot amount is reset to a zero value in step S+5.

Therefore, in the control flow of FIG. 3 above, step S
3 and S4 constitute a deceleration detecting means 35 that determines that the engine speed is Ne>A and the throttle valve opening is fully closed, and detects when the engine is in decelerated operation. Also, step S6* Ss ~SIO,S+
According to No. 21 913, during deceleration operation detected by the deceleration detection means 35, the control valve 16 of the air amount adjustment means 30 is controlled to increase the amount of bypass air in the bypass passage 15, thereby increasing the amount of intake air of the engine. It constitutes an increase control means 36. Further, in steps Sl+ and SI5 of the same control flow, while the increase control means 36 is initially setting the dashpot amount to a predetermined value X and increasing the intake air amount, the speed change detection means 29 detects When the downshift from 2nd gear to 1st gear is detected and the shift execution flag FAT becomes FAT-1, the dashpot amount is forcibly set to zero and the intake air is reduced. Limiting means 37 configured to limit the increase in amount to a small amount
It consists of

Therefore, in the above embodiment, as shown in FIG. 4, the engine speed Ne is the dashpot execution speed A.
During deceleration operation in which the throttle valve opening is fully open and the idle switch 23 is turned OFF in a situation where the engine speed exceeds 1, the dashpot amount is initialized to the predetermined value X when the engine speed Ne decreases to the dashpot execution speed A. Set.

Then, as long as the throttle valve opening remains fully open and the automatic transmission 17 does not change gears, the dashpot amount is attenuated from the initial value ff1KIDGDP.
It gradually decreases. As a result, even if the throttle valve opening is fully closed, the engine speed No. will be suppressed from a sudden drop and will fall smoothly by the amount of increase in bypass air amount.

Now, during the deceleration operation described above, the automatic transmission 17 performs a downshift in accordance with the deceleration, and when the dashpot amount is attenuated, for example, if there is a downshift from 2nd speed to 1st speed. Conventionally, the dashpot amount continues to gradually attenuate, as shown by the broken line in the figure. However, in this embodiment, the dashpot amount after downshifting to 1st gear is forcibly set to zero, so even if there is a downshifting to 1st gear, the engine The rotational speed smoothly decreases as shown by the solid line in the figure without causing any temporary increase.

In the above embodiment, the dashpot amount was forcibly set to zero during downshifting, but the present invention is not limited to this, and the point is to limit the increase in intake air amount during deceleration operation to a small value. Just do it.

Further, in the above embodiment, a case where the transmission is an automatic transmission 17 has been described, but it goes without saying that a manual transmission may also be used.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 to 4 show an embodiment of the present invention, in which FIG. 2 is an overall configuration diagram, FIG. 3 is a flowchart showing control of the amount of bypass air by the controller, and FIG. 4 is an explanatory diagram of the operation. 1... Engine, 8... Throttle valve, 15...
Bypass passage, 16... Control valve, 17... Automatic transmission, 19... Transmission mechanism, 23... Idle switch, 27... Engine controller, 28... Automatic transmission controller, Two...speed change detection means, 3o
...Air amount adjustment means, 35...Deceleration detection means, 36
...Increase control means, 37...Limiting means. Two other people...Engine 8...Throttle valve 15...Bypass passage 16...Control valve 17...One automatic transmission...Transmission mechanism 23...Idle switch 27... Engine river controller 28...Output transmission controller 29...Speed change detection means 30...Air amount 2J adjustment means 35...Deceleration detection means 36...Increase control means 37...Limiting means first Figure 4 Time

Claims (1)

[Claims] (1) Air amount adjusting means for adjusting the intake air amount of the engine; deceleration detecting means for detecting when the engine is decelerating; an increase control means for controlling the air amount adjustment means to increase the amount of air; a shift detection means for detecting a gear change state of a transmission connected to the engine; and during the increase control of the intake air amount by the increase control means An intake air amount control device for an engine, comprising a limiting means for limiting an increase in intake air amount to a small amount when the speed change detection means detects a downshift in which the speed ratio is on the decelerating side.