JPH0231779B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle engine centralized control system, and more particularly to a vehicle engine centralized control system suitable for centrally controlling an engine and a driving force transmission device.

A vehicle engine central control device is used to centrally control fuel injection, ignition timing, gear ratio, etc. However, even with vehicles equipped with this type of device, if you try to start the vehicle when the road surface is slippery due to snow or rain, or if you try to accelerate the vehicle while driving. In this case, it is not possible to perform control to prevent the driving wheel torque from exceeding the road friction force, causing the tires to slip and the vehicle from sliding in the vertical or horizontal direction.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a vehicle engine centralized control device that can quickly perform control to prevent the vehicle from slipping in the vertical or lateral direction.

The present invention, which has been made to achieve the above object, includes: a front wheel speed sensor that detects vehicle speed based on the rotation of the front wheels; a rear wheel speed sensor that detects the vehicle speed based on the rotation of the rear wheels; slip detection means for detecting slip in the driving wheels when the difference between the vehicle speed detection signal from the wheel speed sensor exceeds a predetermined value; and engine control and gear shifting for reducing engine torque when slip is detected by the slip detection means. A transmission torque suppressing means for reducing the torque transmitted from the engine to the drive wheels by controlling the gear shift of the machine to a high speed gear with a low gear ratio, and when wheel slip is no longer detected by the slip detecting means, an engine control canceling means for canceling the engine control by the transmission torque suppressing means; and after a predetermined period of time has elapsed after the engine control is canceled by the engine control canceling means, the gear stage of the transmission is lowered one gear at a time to a lower gear side. The present invention provides a central engine control device for a vehicle, comprising: a shift control canceling means for returning the shift gear to a normal gear position;

In the vehicle engine centralized control device of the present invention configured as described above, first, the slip detection means detects when the difference between the vehicle speed detection signal of the front wheel speed sensor and the vehicle speed detection signal of the rear wheel speed sensor exceeds a predetermined value. Detects drive wheel slip. When a slip is detected by the slip detection means, the transmission torque control means executes engine control to reduce the engine torque and shift control to change the gear position of the transmission to a high speed position with a low gear ratio. Reduces the torque transmitted from the to the drive wheels.

Furthermore, when the transmission torque from the engine to the drive wheels is reduced by the operation of the transmission torque suppressing means and the slip detection means no longer detects wheel slip, the engine control canceling means controls the engine control to reduce the engine torque. is released, and when a predetermined period of time has elapsed thereafter, the shift control canceling means lowers the gear position of the transmission one step at a time to the lower gear side and returns to the normal gear position.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a block diagram of a preferred embodiment of the present invention.

In Figure 1, 2 is the CPU, ROM, RAM,
A control unit consisting of I/O and various registers,
A fuel injection amount control system 6, an ignition timing control system 8, and a gear ratio control system 10 are controlled by detection signals from a sensor group 4 that detects various information regarding vehicle functions.

The sensor group 4 includes front wheel speed sensors 12 and 14 that detect the vehicle speed based on the rotation of the front wheels, rear wheel speed sensors 16 and 18 that detect the vehicle speed based on the rotation of the rear wheels, a water temperature sensor 20, an intake air temperature sensor 22, and a throttle sensor. 24 mag is included. Front wheel speed sensor 1
2 and 14 are sensors that detect the vehicle speed by the rotation of the left and right front wheels, respectively, and the rear wheel speed sensor 1
Sensors 6 and 18 detect the vehicle speed based on the rotation of the left and right rear wheels, respectively.

In this embodiment, the conditions for the tire slipping include vehicle speed detection signals obtained by the front wheel speed sensors 12 and 14 and the rear wheel speed sensor 1.
6 and 18 exceeds a predetermined value (for example, 20 km/h). In addition, in this embodiment, four sensors are provided, namely, front wheel speed sensors 12 and 14 and rear wheel speed sensors 16 and 18, so that tire slip can be reliably detected even if any of the four tires slips. is provided.

Detection signals from the vehicle speed sensors 12 and 14 and the rear wheel speed sensors 16 and 18 are supplied to the control section 2, respectively.

The control unit 2 receives detection signals from various sensors in the sensor group 4 and performs various calculations to control the fuel injection amount control system 6, the ignition timing control system 8, and the gear ratio control system 10.
outputs a control signal for controlling the The control unit 2 also receives detection signals from the front wheel speed sensors 12, 14 and the rear wheel speed sensors 16, 18, and when the difference between these vehicle speed detection signals exceeds a predetermined value, it determines that the tire has slipped, and stops the engine from running. It outputs a control signal to reduce the torque transmitted to the drive wheels.

In this embodiment, as a control signal for reducing the torque transmitted from the engine to the drive wheels,
A control signal for performing fuel cut is output to the fuel injection amount control system 6, and a control signal for minimizing the gear ratio of the gears of the transmission is output to the gear ratio control system 10.

In addition, in this embodiment, the front wheel vehicle speed sensor 1
Vehicle speed detection signal by 2, 14 and rear wheel vehicle speed sensor 1
The vehicle speed detection signals 6 and 18 are the average vehicle speed signals of the front wheel speed sensors 12 and 14 and the average vehicle speed signals of the rear wheel speed sensors 16 and 18, respectively.

Further, the control signal that minimizes the speed ratio is a control signal that sets the gear position to the high speed position. For example, if the gear is configured with four forward speeds, this is the control signal that sets the gear position to the fourth speed.

The present embodiment has the above-mentioned configuration.Next, the slip detection processing routine will be explained based on the flowchart shown in FIG.

First, in step 100, the rear wheel speed sensor 1
6 and 18, the vehicle speed of the rear wheels is detected, and in step 102, the front wheel speed sensors 12 and 14 detect the vehicle speed of the front wheels. The detection signals of the front wheel speed sensors 12, 14 and the rear wheel speed sensors 16, 18 are supplied to the control section 2, and the average vehicle speed of the rear wheels and the average vehicle speed of the front wheels are calculated in step 104 and step 106, and then in step 108. The vehicle speed difference between the front wheels and the rear wheels is calculated.

Next, the process moves to step 110, where it is determined whether or not there was a previous slip. This determination is made at predetermined intervals, for example, every 5 milliseconds. At step 110
If the determination is NO, the process moves to step 112 and the vehicle speed difference is determined. That is, it is determined whether the vehicle speed difference is greater than or equal to a predetermined value. step 112
If the determination is NO, it means that there is no slip, and the slip detection routine ends. If the determination in step 112 is YES, the process moves to step 114, where a control signal for performing a fuel cut is output. At this time, in step 116, a flag is set in the register of the control section 2 for controlling when a slip occurs. Subsequently, at step 118, a control signal for prohibiting downshifting is output to the gear ratio control system 10, and the slip detection processing routine is completed.

If the determination in step 110 is YES, the process moves to step 120, where it is determined whether the vehicle speed difference is less than or equal to a predetermined value. If YES is determined in step 120, no slip will occur, so
The process moves to step 122, where a control signal for injecting a predetermined amount of fuel is output to the fuel injection amount control system 6. Subsequently, in step 124, a control signal enabling downshift execution is output to the gear ratio control system 10, and the slip detection processing routine is completed.

If the determination in step 120 is NO, it means that a slip has occurred, and the process moves to step 126.
Here, it is determined whether or not a fuel cut has been performed. If the determination in step 126 is NO, the process moves to step 114, and the processes of steps 114, 116, and 118 are performed in the same manner as described above. If the determination in step 126 is YES, the process moves to step 128, where the engine speed is below a predetermined speed (for example,
800 rotations or less).
If the determination in step 128 is NO, the slip detection processing routine ends. If the determination in step 128 is YES, the process moves to step 122, where steps 12 and 124 are performed in the same manner as described above, and the slip detection processing routine is completed.

As described above, in this embodiment, the average vehicle speed of the rear wheels and the average vehicle speed of the front wheels are detected, and when the difference between these vehicle speeds exceeds a predetermined vehicle speed, it is determined that a slip has occurred and a fuel cut is performed. When the vehicle speed of the front and rear wheels falls below a predetermined vehicle speed due to the fuel cut, normal fuel injection is performed. Further, even if the vehicle speed difference does not become less than a predetermined value after the fuel cut is performed, normal fuel injection is performed when the engine speed becomes less than the predetermined speed.

Next, the shift position determination routine will be explained based on the flowchart shown in FIG.

First, in step 200, vehicle speed detection signals from the throttle sensor 24, which detects the opening degree of the throttle, and the vehicle speed sensor, which detects the vehicle speed, are supplied to the control section 2, and the shift position required during normal driving is calculated. Ru. In addition, the vehicle speed detection signal in this case is the rear wheel vehicle speed sensor 16, 18 described above.
The detection signal is used. Then step
The process moves to 202, where it is determined whether or not there was a previous slip. For this determination, the determination in step 110 shown in FIG. 2 is used. Step 202
If NO is determined in step 204, the control signal for the shift position calculated in step 200 is output to the gear ratio control system 10, and the shift position determination routine ends.

If YES is determined in step 202, the process moves to step 206, where it is determined whether or not to shift down. The determination at step 206 uses the processes at step 118 and step 124 shown in FIG. The signal is output to the ratio control system 10, and the shift position determination routine ends.

If the determination in step 206 is YES, the process proceeds to step 210, where it is determined whether a certain period of time has elapsed since the fuel cut was restored. Here, if the determination is NO, the shift position determination routine ends, and if the determination is YES, the routine moves to step 212. In step 212, if the shift position is 4th gear, calculation is performed to set the shift position to 3rd gear, and step 214 is performed.
Move to.

In step 214, it is determined whether the shift position calculated in step 212 is larger than the shift position calculated in normal driving. For example, if the shift position obtained in step 212 is 3rd gear and the shift position obtained through normal driving is 2nd gear, then
It is judged as YES. If the determination in step 214 is YES, the process moves to step 216, where the control signal for the shift position determined in step 212 is output to the gear ratio control system 10, and the shift position determination routine ends. NO in step 214
If it is determined that
0, and the shift position determination routine ends.

As described above, in this embodiment, when a slip is detected, a control signal is output that shifts the gear to a high-speed shift position. Further, even after the slip is released, a shift position control signal is output that sequentially changes from high speed to low speed, resulting in the shift position required for normal driving.

As explained above, according to the present invention, there is an excellent effect that slips at the time of starting the vehicle or slips at the time of acceleration while running can be promptly prevented and the vehicle can run safely. In addition, after slip suppression, engine control is first released, and then after a predetermined period of time has elapsed, the gear position is lowered one step at a time to the lower gear side, and the gear position is returned to the normal gear position. The torque transmitted to the drive wheels will gradually increase,
After the control is restored, slips can be prevented from occurring again.

In other words, even if slips no longer occur due to engine control and shift control, if these controls are subsequently restored at the same time, the torque transmitted to the drive wheels will rise rapidly, potentially causing large slips to occur again. However, in the present invention, after a predetermined period of time has passed after the end of engine control, the gear is shifted to a lower gear.
By lowering the gear position step by step and returning to the normal gear position, the torque transmitted to the drive wheels is prevented from increasing rapidly, and slippage does not occur again when control is restored.

Further, even if the slip occurs again during the return of the gear position, the engine control and shift control are executed again, so the slip can be suppressed in a short time. In other words, hydraulic pressure is normally used to change gears, and shift control takes time due to response delays in the hydraulic system, so if control is restored from shift control, the drive wheels will It is not possible to quickly reduce the torque transmitted to
In the present invention, the gear position is restored after engine control is released, so when slip occurs again, the engine control can quickly suppress the torque transmitted to the drive wheels, thereby shortening the time it takes to occur. You will be able to do this.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a flowchart for explaining a slip detection processing routine, and FIG. 3 is a flowchart for explaining a shift position determination routine. be. 2... Control unit, 4... Sensor group, 6... Fuel injection amount control system, 8... Ignition timing control system, 10... Gear ratio control system, 12, 14... Front wheel speed sensor, 1
6,18...Rear wheel speed sensor.

Claims (1)

[Scope of Claims] 1. A front wheel speed sensor that detects vehicle speed based on the rotation of the front wheels; a rear wheel speed sensor that detects the vehicle speed based on the rotation of the rear wheels; a vehicle speed detection signal from the front wheel speed sensor and a vehicle speed detection signal from the rear wheel speed sensor. slip detection means for detecting slip in the driving wheels when the difference between the signal and the signal exceeds a predetermined value; and when slip is detected by the slip detection means, engine control is performed to reduce the engine torque, and the gear position of the transmission is changed to a gear. transmission torque suppressing means that performs gear change control to switch to a high speed gear with a low ratio to reduce the torque transmitted from the engine to the driving wheels; and when the slip detection means no longer detects wheel slip, the transmission torque suppressing means an engine control canceling means for canceling the engine control; and after a predetermined period of time has elapsed after the engine control is canceled by the engine control canceling means, the gear position of the transmission is lowered one gear at a time to the lower gear side to return to the normal gear position. 1. A vehicle engine centralized control device comprising: gear change control canceling means for returning to normal mode.