JPS60199739A - Slip prevention unit for car - Google Patents

Abstract

PURPOSE:To prevent the deterioration of drivability by controlling a power transmission system between an engine and driving wheels to prevent the slip of the driving wheels occurring when an excessive engine brake is applied. CONSTITUTION:A slip prevention unit 5 detects whether a brake pedal is depressed based on a signal of a brake switch 3, a detects the slip state of driving wheels 10 based on signals of speed sensors 1, 2, when the driving wheels 10 are going to be locked even though the brake pedal is not depressed, it judges that the engine brake is excessive and commands a clutch control unit 6 to remove an electromagnetic fluid clutch 7, thus an excessive engine brake force is prevented from being transmitted to the driving wheels 10 and the slip due to the lock of the driving wheels 10 is avoided. Furthermore, the clutch control unit 6 cuts off the electromagnetic fluid clutch 7 not based on a signal of a clutch sensor 4 when a clutch cutoff command is inputted from the slip prevention unit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a slip prevention device for a vehicle that prevents slippage of drive wheels during engine braking of a vehicle.

(Prior art) Conventionally, this type of device is disclosed in Japanese Patent Application Laid-Open No. 58-857, for example.
As shown in No. 47, the adjustment device is actuated by the generation of both the output signal of the anti-skid device that detects wheel slippage and the non-braking signal of the brake sensor that detects that the brake is not activated, and the engine A device has been proposed that prevents wheel slip during engine braking by accelerating the engine and maintaining the engine acceleration until the above-mentioned slip disappears.

However, this device requires an adjustment device to adjust the operation of the engine, and by controlling the acceleration of the engine, it indirectly tries to prevent slippage of the drive wheels during engine braking, so the slippage There is a time delay from the time of detection until the rotation of the drive wheels increases via engine acceleration, which may result in vertical fluctuations in vehicle speed due to slip prevention control of the drive wheels during engine braking, and deterioration of drivability. There is a problem.

(Object of the Invention) The present invention has been made in view of the above-mentioned problem, and it quickly detects /l when detecting the slip of the driving wheels during engine braking. The objective is to prevent slippage of the drive wheels through smooth control, reduce vertical fluctuations in vehicle speed at that time, and prevent deterioration of drivability.

(Structure of the Invention) For this purpose, in the present invention, as shown in the basic configuration diagram in FIG. and a control means d for determining a slip state of the driving wheels due to a decrease in the speed of the driving wheels and generating a control signal when the non-braking state is detected based on the signal, A power control means e is provided to reduce the power transmitted between the drive wheels g of the vehicle and the engine 1 in response to a control signal, thereby preventing the drive wheels g from slipping during engine braking.

(Example) The present invention will be described below with reference to embodiments shown in the drawings.

FIG. 1 shows the configuration of a vehicle slip prevention device according to the present invention. In Fig. 1, 1 is a driving wheel speed sensor that detects the driving wheel speed, 2 is a driven wheel speed sensor that detects the driven wheel speed, 3 is a brake switch that detects whether the brake pedal is depressed, and 4 is a clutch pedal switch. A clutch sensor 5 uses a microcomputer to detect the amount of displacement,
A slip prevention device that prevents the drive wheels from locking; 6 a clutch control device that generates a clutch disengagement signal based on the signals from the clutch sensor 4 and the slip prevention device 5; 7 an electromagnetic fluid clutch; The power transmission system leading to the transmission 9 and the drive wheels 10 is switched between a connected state and a disconnected state. 11 is a throttle switch that detects whether or not the throttle valve of the engine 8 is closed.

Furthermore, in the slip prevention device 5, 51 is a central processing unit (CPU) that performs calculations such as slip determination,
52 is a counter that counts pulses +11 from each speed sensor 1, 2; 53 is an input device that inputs signals from each speed sensor 1, 2 and brake switch 3; 54 is a random counter for temporarily storing calculation results, etc. Access memory (R
AM), 55 is a read-only memory (ROM) that stores calculation programs and control data, and 56 is an output device that outputs a control signal to the clutch control device 6.

Next, the operation of the above configuration will be explained.

Now, the anti-slip device 5 detects whether the brake pedal is depressed from the signal of the brake switch 3, detects the slip state of the drive wheel 10 from the signals of each speed sensor 1, 2, and detects that the brake pedal is not depressed. However, driving wheels 10
When the engine brake is about to lock, the clutch control device 6 is commanded to disengage the electromagnetic fluid clutch 7 because the engine brake is excessive, and the excessive engine brake is transmitted to the drive wheels IO. to prevent the driving wheel 10
Avoid slippage due to locking. Further, the clutch control device 6 normally drives and controls the electromagnetic fluid clutch 7 based on the signal from the clutch sensor 4 to perform clutch operation, but when a clutch disengagement command is input from the slip prevention device 5, The electromagnetic fluid clutch 7 is disengaged regardless of the signal from the clutch sensor 4.

Next, the detailed operation of the anti-slip device 5 using a microcomputer will be explained with reference to the flowchart shown in FIG. First, when the process starts, in step 100 it is determined from the output of the brake switch 3 whether the brake pedal is depressed and the brake is in operation, and if the brake is in operation, the process proceeds to step 106; Then, the output device 56 instructs the clutch control device 6 to perform normal clutch control, and returns to step 00. On the other hand, if the brake is not in operation, step 101 is executed.
Proceed to. In step 101, the driving wheel speed Vw is calculated from the output of the driving wheel speed sensor 1, in step 102, the driven wheel speed VV is calculated from the output of the driven wheel speed sensor 2, and in step 103, the driven wheel speed Vv is multiplied by (K=0.5~
0.9, for example = 0.8) I, create a slip judgment level V, and in step 104 compare the driving wheel speed Vw with the slip judgment level V1- to determine if the driving wheel 1.0 is slipping. In other words, it is determined whether the drive wheels are about to lock. If VW≧vT and VW (VT is not established, that is, if the driving wheels 10 are not likely to lock, in step 106, the output device 56 instructs the clutch control device 6 to perform normal clutch control, Return to step 100.

On the other hand, if Vw > VT is established in step 104, and if the drive wheels 10 are about to lock, then in step 107, it is determined from the output of the throttle switch 11 whether the throttle valve is closed, If it is determined that the throttle valve is closed, the engine torque increases and the engine brake becomes smaller, and the process proceeds to step 106, where normal clutch control is performed on the clutch control device 6. A command is given from the output device 56 to do so, and the process returns to step 100. On the other hand, if it is determined in step 107 that the throttle valve is closed, the process proceeds to step 105, in which the clutch control device 6 is commanded to disengage the electromagnetic fluid clutch 7, Return to step 100.

Therefore, when the engine brake is excessive, the clutch is disengaged to prevent transmission of the engine brake force to the drive wheels 10, so locking of the drive wheels 10 can be avoided and safe driving is possible.

In the above-described embodiment, only the engagement and engagement of the clutch is controlled, but more precise control may be performed by controlling the amount of slippage of the clutch, that is, the degree of half-clutching.

Furthermore, although the clutch control device 6 controls the electromagnetic fluid clutch 7 using the clutch sensor 4, it may be an automatic clutch control device that operates the clutch according to vehicle speed, engine speed, shift operation, etc., and the clutch may be an electromagnetic fluid clutch. Alternatively, a hydraulic clutch may be used instead.

Further, although the clutch is controlled in the above embodiments, the same effect can be obtained by controlling the shift position of the transmission and shifting to the neutral position instead of disengaging the clutch.

(Effects of the Invention) As described above, in the present invention, slippage of the drive wheels due to excessive engine braking can be prevented by quick and smooth control during non-control times when the brake pedal is not depressed. Moreover, because the power transmission system between the engine and the drive wheels is directly controlled, the control response is fast, and therefore, it is possible to reduce vertical fluctuations in vehicle speed during control, and prevent deterioration of drivability. It has the excellent effect of being able to

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing its operation, and FIG. 3 is a basic configuration diagram showing the concept of the present invention. DESCRIPTION OF SYMBOLS 1... Drive wheel speed sensor, 2... Driven wheel speed sensor, 3... Brake switch, 5... Slip prevention device, 6... Clutch control device, 7... Electromagnetic fluid clutch, 8 ...Engine, 9...Transmission, 10...
driving wheels. Representative Patent Attorney Takashi Okabe

Claims (1)

[Claims] (1) A driving wheel speed detecting means for detecting the driving wheel speed, a driven wheel speed detecting means for detecting the driven wheel speed, and a brake detecting means for detecting the operating state of the brake of the vehicle, and a signal from the brake detecting means a control means for determining a slip state of the driving wheel due to a decrease in the driving wheel speed based on the driving wheel speed and the driven wheel speed when detecting a non-braking state, and generating a control signal; What is claimed is: 1. A slip prevention device for a vehicle, comprising: power control means for reducing power transmitted between a drive wheel and an engine of the vehicle. (2. In claim 1, the vehicle slip prevention device is characterized in that the power control means controls a clutch that connects and disconnects power transmission. .