JPS61157728A - Racing preventive device or driving wheel - Google Patents

Abstract

PURPOSE:To prevent racing of a driving wheel, by deciding the racing through a control unit on the basis of a signal from a rotary speed sensor detecting a speed of the driving wheel and closing in accordance with a condition of the racing a throttle valve through a control of the positive pressure by a solenoid valve. CONSTITUTION:When a vehicle is driven running, an engine 9 equipping a supercharger 1 always detects a rotary speed of a driving and a driven wheel respectively by sensors 30, 31. And when a difference between the rotary speeds by each sensor 30, 31 increases to a preset value or more, a device, deciding the difference as the racing, outputs a signal in accordance with a speed of the racing from a subtraction circuit 33 while a duty signal, increasing its duty value larger as the racing increases larger, from a comparator circuit 35. In this way, a solenoid valve 24 opens applying a positive pressure based from the supercharge pressure to a control chamber 20a of an actuator 20 so as to close a throttle valve 21. Accordingly, the engine, restricting by the throttle valve 21 the suction of air pressurized by a compressor 1a of the supercharger 1 and decreasing an output of the engine, enables the racing to be eliminated.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a drive wheel slip prevention device for a vehicle such as an automobile, and more particularly to a device that controls engine output when the drive wheels idle.

[Background of the invention]

When the vehicle suddenly starts or accelerates, the drive wheels may spin. This is determined by whether the drive tires rotate tightly against the road surface when the vehicle is running, or whether they slide on the road surface, and there is something called the adhesion force of the drive wheels that determines whether there is skidding or not. . This adhesion force Fa is expressed by the following equation based on the adhesion coefficient μ between the road surface and the tire and the load W applied to the drive wheel. Fa=μ・W In addition, the driving force Fe acting on the driving wheels is expressed by the following formula using the entrainment output torque T, the gear ratio 1.power transmission efficiency η, and the tire effective diameter.Fe=Ni・T・1・η/D Therefore, it can be said that idling of the driving wheels occurs when the state of Fe>Fa is reached due to a decrease in the adhesion coefficient μ or an excessively low engine output torque.Such idling of the driving wheels occurs when the driving force This results in loss of fuel efficiency, worsening of fuel efficiency, and deterioration of acceleration performance, and changes in attitude such as understeer, oversteer, and poor straightness while turning or going straight, impairing safety.

[Conventional technology]

So conventionally, the driver's accelerator work was done. The drive wheels are operated to prevent them from spinning by means of clutch engagement, etc., and currently, automobiles do not have a system to prevent them from spinning. Here, in order to directly prevent the above-mentioned wheel slip, it is possible to detect the adhesive force of the driving wheels and limit the engine output so that the driving force does not become larger than that. However, such a method cannot be adopted because the adhesion coefficient μ between the tire and the road surface varies depending on various factors and is difficult to actually measure. In addition, conventional methods for limiting engine output include those that retard the ignition timing as shown in Japanese Patent Application Laid-open No. 57-49070, and dual carburetors as shown in Japanese Patent Application Laid-Open No. 49-65425. A device that closes the secondary side of
-As shown in Japanese Patent Publication No. 141020, the wastegate is controlled according to operating conditions such as rotation speed and accelerator operation, and as shown in Japanese Patent Application Laid-open No. 156929/1984, the amount of fuel injection is reduced depending on acceleration, etc. , etc., but these take engine safety measures, fuel economy savings, etc. into consideration.

[Problems that the invention attempts to solve] In the case of the above-mentioned conventional systems in which the slip prevention is dependent only on the driver's operation, there is always a possibility of slipping, and there are problems such as the driver not noticing the slipping, or difficulty in accelerating to prevent it. be. Particularly on snowy, rainy, dirt, or other road surfaces, spinning is likely to occur, and it is desirable to take measures to ensure safety. [Means to solve the problem]

In view of the above-mentioned points, it is an object of the present invention to provide a drive wheel idling prevention device that controls engine output so that idling of the driving wheels does not continue. The means for this purpose is to install a throttle valve equipped with a diaphragm actuator in the intake system downstream of the supercharger compressor of a supercharged engine, and an operation chamber that closes the throttle valve using the positive pressure of the actuator. , which communicates with the downstream side of the compressor through a passage having a positive pressure control solenoid valve and communicates with the atmosphere through a passage with an orifice to form an engine output reduction mechanism, which reduces at least the rotational speed of the driving wheels. The control unit determines idling based on a signal from a rotation sensor that detects the idling, and the solenoid valve performs positive pressure control depending on the idling state.

[Function 1] Based on the above configuration, the rotation sensor detects at least the rotation speed of the drive wheels to constantly determine whether or not there is idling.
If idling occurs, the solenoid valve applies positive pressure based on the supercharging pressure to the actuator operation chamber and closes the throttle valve, reducing the output of the supercharged engine and thus preventing the drive wheels from idling. is avoided initially. [Embodiment 1] Hereinafter, one embodiment of the present invention will be specifically described based on the drawings. In the drawings, a supercharged engine to which the present invention is applied will be described. Reference numeral 1 indicates a supercharger, and the suction side of a compressor 1a is connected to an air cleaner 3 via a duct 2.
The air 70 immediately downstream of the meter 4 is connected to the air 70, and its discharge side is connected to the intake pipe 5. Throttle body 7 with throttle valve G
, communicates with the engine body 9 via the intake manifold 8. Further, an exhaust pipe 10 from the engine body 9 is configured to communicate with the turbine 1b of the supercharging l11, and supercharging is performed by driving the supercharger with exhaust energy at a predetermined engine speed or higher. There is. On the other hand, an exhaust bypass passage 11 is connected to the turbine 1b of the supercharger 1 in a detour manner, and a wastegate valve 13 having a diaphragm actuator 12 is installed in the bypass passage 11. The actuator 12 opens the wastegate valve 13 using boost pressure.
The operation chamber 12a communicates with a boost pressure boat 15 on the downstream side of the compressor via a passage 14, and forms a boost pressure control device 16. In the above configuration, a throttle valve 21 including a diaphragm actuator 20 is provided as an engine output reduction mechanism in the middle of the intake pipe 5 on the downstream side of the compressor of the supercharger 1. The actuator 20 closes the throttle valve 21 with positive pressure, and its operation chamber 20a communicates with a positive pressure port 23 on the downstream side of the compressor via a passage 22, and a solenoid valve 24 for pressure control is provided in the middle of the passage 22. is provided. The operation chamber 20a further communicates with an atmospheric port 27 on the upstream side of the compressor via a passage 26 having an orifice 25, and is configured to determine the degree of closing of the throttle valve 21 in accordance with the positive pressure controlled by the solenoid valve 24. It has become. It also has rotation sensors 30, 31 that detect the rotation speed of the driving wheel and the driven wheel, and these rotation sensors 30 and 31 are connected to a subtraction circuit 33 in the control unit 32, and when the difference in rotation speed is equal to or greater than a set value, In this case, it is determined that the drive wheels are spinning, and a signal with a value corresponding to the magnitude is output. The subtraction circuit 33 is connected to a comparison circuit 35 via an integration circuit 34, and a triangular wave generation circuit 36 is also connected to this comparison circuit 35, so that the greater the slippage, the greater the duty value will be output. The comparison circuit 35 is connected to the solenoid valve 24 via the driving transistor 37. Next, the operation of the idling prevention device configured as described above will be explained. First, when the vehicle is running, the rotational speeds of the driving wheels and driven wheels are constantly detected by the rotational sensors 30 and 31, and if the rotational speeds of both wheels substantially match and no slip occurs, the subtraction circuit 33 of the control unit 32 The output is very small, so the comparison circuit 35 outputs a signal with a duty value of 0%. Therefore, the solenoid valve 24 is fully opened, and the operating chamber 20a of the actuator 20 is brought to atmospheric pressure, thereby fully opening the throttle valve 21. Therefore, by driving the supercharger 1 during high-load operation, all of the air pressurized by the compressor 1a is sucked into the engine body 9, thereby generating a predetermined high engine output. When a predetermined supercharging pressure is reached in this supercharging zone, the actuator 12 opens the wastegate valve 13 to release a portion of the exhaust gas, thereby controlling the supercharging pressure to be substantially constant. On the other hand, in the above-mentioned high-load operation, when the engine output is high during supercharging, if the difference in the rotation speed detected by the rotation sensor 30. The comparison circuit 35 outputs a duty signal having a larger duty value as the idle speed increases. Therefore, the solenoid valve 24 opens in response to the duty signal, and positive pressure based on the supercharging pressure is applied to the operation chamber 20a of the actuator 20, and accordingly, the throttle valve 21
The valve closes in such a way that the greater the slip, the more it closes. Therefore, the intake of air pressurized by the compressor 1a of the supercharger 1 is restricted by the throttle valve 21, and the engine output is reduced, and accordingly, the driving force of the drive wheels is also reduced, thereby eliminating the idling. Note that when the throttle valve 21 is closed, the supercharging pressure immediately downstream of the compressor 1a of the supercharger 1 increases. Therefore, the amount of exhaust gas released by the wastegate valve 13 increases and the supercharging pressure decreases, which also causes the engine output to decrease. Although one embodiment of the present invention has been described above, it is not limited to the above embodiment. Judgment of slippage can also be made based on the rotational acceleration and angular acceleration of the drive wheels, and if necessary, it can be applied not only to two-wheel drive vehicles but also to four-wheel drive vehicles. Effects of the Invention As is clear from the above description, according to the present invention, slipping of the drive wheels during sudden start and acceleration is prevented at an early stage, and IR
Especially in snow, rain, and ice burns. This eliminates changes in the vehicle's posture on roads such as dirt, increasing safety. There is less loss of driving force, worse fuel efficiency, and abnormal tire wear, resulting in improved acceleration performance.It is highly effective when applied to supercharged engines that have high engine output and are prone to spinning of the drive wheels. Since it is configured to restrict intake of pressurized air by the supercharger during idling, it is possible to effectively reduce engine output and eliminate idling.The throttle valve is operated with positive pressure based on the supercharging pressure. Since the engine output is reduced according to the idle state, control is easy and the output performance does not deteriorate due to an excessive reduction in the engine output.

[Brief explanation of drawings]

The drawings do not show one embodiment of the apparatus according to the present invention, but are block diagrams. DESCRIPTION OF SYMBOLS 1... Supercharger, 1a... Compressor, 5... Intake pipe, 9... Engine body, 20... Actuator, 21... Throttle valve, 22. 26... Passage, 24・
... Solenoid valve, 25... Orifice, 30.3
1... Rotation sensor, 32... Control unit, 33.
... Subtraction circuit, 34 ... Integration circuit, 35 ... Comparison circuit, 3G ... Triangular wave generation circuit.

Claims (1)

[Claims] A throttle valve equipped with a diaphragm actuator is installed in the intake system downstream of the supercharger compressor of a supercharged engine, and a positive pressure control solenoid valve is installed in the operation chamber that closes the throttle valve using the positive pressure of the actuator. The compressor communicates with the downstream side of the compressor through a passage having A drive wheel slip prevention device characterized in that a control unit determines whether the wheel is slipping based on a signal, and positive pressure control is performed using the solenoid valve according to the slipping state.