JP2554865B2 - Method for controlling throttle valve opening of vehicle engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an accelerator pedal that detects the opening degree of a throttle valve of a vehicle engine connected to a transmission through a clutch by an accelerator pedal position sensor. The present invention relates to a throttle valve opening control method for controlling according to the amount of depression.

(Prior Art) Conventionally, instead of mechanically interlocking the throttle valve of the engine with the accelerator pedal to open and close, the amount of depression of the accelerator pedal is detected by a position sensor, and the throttle valve is depressed by a pulse motor or the like. It is known that the valve is opened to an opening corresponding to the amount.

(Problems to be solved by the invention) By the way, in a high rotation type engine, that is, an engine in which the intake and exhaust valve has a large overlap so that a high torque can be obtained even in a high rotation range, the output torque of the engine in the low rotation range is As a result, there is a problem that it is difficult for a driver with a low degree of skill to control the accelerator and the clutch when starting.
In this case, in the case of mechanically interlocking the throttle valve with the accelerator pedal, the opening degree of the throttle valve is uniquely determined according to the depression amount of the accelerator pedal, but the opening degree of the throttle valve is determined by the position sensor of the accelerator pedal. With a signal that is electrically controlled by the signal from, it is possible to open the throttle valve to an opening different from the opening corresponding to the amount of depression of the accelerator pedal depending on the program. In a state where engine stall occurs, it is desirable to increase the throttle valve opening so that smooth start can be achieved.

An object of the present invention is to provide a control method that meets such a demand.

(Means for Solving Problems) In order to achieve the above object, the present invention detects the opening degree of a throttle valve of a vehicle engine connected to a transmission through a clutch by a position sensor of an accelerator pedal. In a system that is controlled according to the amount of depression of the accelerator pedal, when the vehicle is started, the rotational speeds of the input shaft and the output shaft of the clutch are detected, and the amount of change in the rotational speed of the output shaft is a predetermined value. When the number of revolutions of the output shaft is lower than the number of revolutions of the input shaft, the throttle valve is opened larger than the opening corresponding to the depression amount of the accelerator pedal by a predetermined addition value, and The addition value is variably set according to the change amount of the rotation speed of the output shaft and the gear ratio.

(Operation) The condition that the amount of change in the rotational speed of the output shaft of the clutch is greater than or equal to the specified value and the condition that the rotational speed of the output shaft is lower than the rotational speed of the input shaft satisfy the condition of the output shaft in the semi-clutch state. Is driven from the engine side and the vehicle starts to move.At this time, a large load acts on the engine and the throttle valve is opened to an opening degree corresponding to the depression amount of the accelerator pedal. In the case of, the engine stall is likely to occur due to insufficient depression of the accelerator pedal,
According to the present invention, the throttle valve is opened to an opening larger than the opening to increase the output torque of the engine, and even if the accelerator pedal is not sufficiently depressed, the engine stall does not occur and the starting operation becomes easy.

(Embodiment) Referring to FIG. 1, (1) shows a vehicle engine connected to a transmission (2) through a clutch (3), and (4) shows a control circuit composed of a micro computer. The throttle valve (5) of the engine (1) is opened and closed by the pulse motor (6) operated by the output from the control circuit (4).

The control circuit (4) outputs an output signal from a position sensor (8) that detects the amount of depression of the accelerator pedal (7) (hereinafter referred to as Θ _p ) and the opening degree of the throttle valve (5) (hereinafter referred to as Θ _th . Output signal from the opening sensor (9) for detecting
Each rotation speed sensor (10 ₁ ) (10 ₁ ) (10) that detects the rotation speed of the input shaft (3a) of the clutch (3) (hereinafter referred to as N ₁ ) and the rotation speed of the output shaft (3b) (hereinafter referred to as N ₂ ) ₂ ) output signal from
An output signal from a vehicle speed sensor (11) that detects the number of rotations on the output side of the transmission (2), that is, a vehicle speed (hereinafter referred to as V), and a sensor (12) that detects a shift position of the transmission (2). In response to the signal, an opening command signal for the throttle valve (5) is output in accordance with the program shown in FIG. 2, and the pulse motor (6) is operated so that Θ _th becomes a command value (hereinafter referred to as "command value"). It works as expected.

In the following, this program will be described. First, Θ _p , Θ _th , N ₁ , N ₂ , V is input in S1, it is determined in S2 whether V is less than Vmin which is an extremely low speed, and the determination result is " If YES, rewrite flag F to 1 in S3 to S4, and if NO, directly S4.
Then, it is determined whether F = 1 in S4. If the determination result is "YES", the process proceeds to S5 to determine whether Θ _th is larger than a predetermined value A, and the determination result is "NO. , The shift position is read in S6, and then in S7, the change amount of N ₂ , that is, the difference ΔN ₂ between the value N _{2n of} N ₂ input this time and the value N _{2n-1 of} N ₂ input last time
After determining, the process proceeds to S8, and it is determined whether or not ΔN ₂ is equal to or more than the predetermined value B. If the determination result is “YES”, the process proceeds to S9 and N
_It is judged whether ₂ is lower than N ₁ , and the judgment result is "Y
If “ES”, proceed to S10. Here, the value of B is comparatively equivalent to the change amount of N ₂ when the clutch (3) starts to be connected in a semi-clutch state and the output shaft (3b) starts to be driven by torque transmission from the engine (1) side. It is assumed that the value is set to a small value, and when the accelerator pedal (7) is not stepped on too much at the time of starting and the vehicle is in a half-clutch state, S2, S3, S4, S5, S
If the shift position read in S6 is 1st speed, then S10 to S11, and if it is 2nd speed, S1
From 0 to S12 to S13, and if it is the third speed or higher, the process proceeds from S12 to S14 to set the addition value ΔΘ, and then at S15, Θ _p
Is calculated by adding ΔΘ to, then Θ _th becomes larger than the opening corresponding to Θ _p by ΔΘ, and the engine torque increases to increase the accelerator pedal (7).
Engine stall due to insufficient pedaling is prevented.

By the way, when the clutch (3) is connected relatively quickly,
As ΔN ₂ increases, the load acting on the engine (1) also increases and engine stalls easily occur.
Since a larger engine torque is required when starting at the first speed than when starting at the first speed, ΔΘ is changed in accordance with ΔN ₂ at the first speed, for example, as shown by line a in FIG. It is desired to change the value as shown in the line b in the figure so that it becomes a value larger than the first speed at the first speed, so at the time of starting the first speed, the value of ΔΘ is calculated from the first table in which the characteristics of the a line are written in S11. At the time of reading or starting from the 2nd speed, from the second table in which the characteristics of the b line are written in S13, △
The value of Θ was read out and this value was added to Θ _p .

It should be noted that the vehicle is started in the third or higher speed stage when the vehicle can be started with a light load such as a downhill. In this case, S14
Was set to a constant and relatively small value Θ ₁ .

The clutch (3) is directly connected after the start operation is completed.
When N ₁ = N ₂ , it is determined to be “NO” in S9, the process proceeds to S17,
Is set equal to Θ _p , and then the flag F is rewritten to 0 in S18, and then the process proceeds to S16, where the value equal to Θ _p set in S17 is output, and Θ _th is controlled to the opening corresponding to Θ _p , After that, as the vehicle speed increases, it is determined to be "NO" in S2 and proceed directly to S4, where it is determined to be "NO" and proceed to S17, S18, S16, which is repeated and Θ _th is the opening corresponding to Θ _p. Maintained at.

If Θ _th is larger than A, S5
Is judged as “YES” in S17 and the process proceeds to S17, and further clutch (3)
Even when the valve is in the disconnected state, it is determined to be “NO” in S8 and the process proceeds to S17, where Θ _th is controlled to the opening corresponding to Θ _p, and the unnecessary opening of the throttle valve (5) does not occur.

(Effects of the Invention) As described above, according to the present invention, the engine stall due to insufficient depression of the accelerator pedal at the time of starting can be reliably prevented, and the starting operation can be facilitated. Further, according to the present invention, it is possible to prevent unnecessary control of the throttle valve before the output shaft starts to be driven, and the addition value is variably set according to the change amount of the output shaft rotation speed and the gear ratio. Therefore, it is possible to prevent engine stall even in a starting mode with a different gear ratio.In addition, when the accelerator pedal depression amount is reduced on a downhill road, etc., the basic opening corresponding to the depression amount decreases and the throttle valve opens accordingly. Since the frequency is reduced, it is possible to perform control that properly incorporates the driver's intention.

[Brief description of drawings]

FIG. 1 is a block diagram of a control device used for carrying out the method of the present invention, FIG. 2 is its flow chart, and FIG. 3 is a diagram showing the relationship between the added value and the amount of change in the output shaft rotation speed. (1) …… Vehicle engine, (2) …… Transmission (3) …… Clutch, (3a) …… Input shaft (3b) …… Output shaft, (4) …… Control circuit (5) …… Slot valve, (7) …… Accelerator pedal (8) …… Accelerator position sensor (9) …… Slottle valve opening sensor (10 ₁ ) …… Input shaft speed sensor (10 ₂ ) …… Output Axis speed sensor

Claims (1)

(57) [Claims] 1. A throttle valve of a vehicle engine, which is connected to a transmission through a clutch, is controlled in accordance with a depression amount of an accelerator pedal detected by a position sensor of the accelerator pedal. When the vehicle starts moving, the rotational speeds of the input shaft and the output shaft of the clutch are detected, and the amount of change in the rotational speed of the output shaft is equal to or greater than a predetermined value and the rotational speed of the output shaft is the rotational speed of the input shaft. When it is lower, the throttle valve is opened larger than the opening degree corresponding to the depression amount of the accelerator pedal by a predetermined addition value, and the addition value is changed with the change amount of the rotation speed of the output shaft and the gear shift. A throttle valve opening control method for a vehicle engine, which is variably set according to the ratio.