JP2899076B2 - Vehicle traction control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a traction control device that reduces a driving force when a driving wheel slips, thereby eliminating the slip, and in particular, a shift shock reduction unit of an automatic transmission. The present invention relates to a traction control device for a vehicle provided.

(Prior Art) Generally, the driving force of a vehicle is controlled by adjusting the engine output by a driver's accelerator operation or the like. However, the driving force transmitted to the driving wheels is excessive with respect to the road surface friction coefficient. In order to prevent the slip of the drive wheels due to the traction control device, a traction control device that automatically controls the driving force in the suppression direction in addition to the control by the operation of the driver as described above has been put to practical use.

In this case, as a method of controlling the driving force by this device, for example, a braking system is used to apply a braking force to a wheel having an excessive driving force by using a brake system as disclosed in Japanese Patent Application Laid-Open No. 57-22948. There are a system, a system for lowering the output torque of the engine, and a system using both of them. Also,
As a method of reducing the output torque of the engine, there are a method of correcting and controlling the ignition timing to the retard side, a method of correcting the opening of the throttle valve in a decreasing direction, and the like.

On the other hand, in a vehicle equipped with an automatic transmission, a shift shock, particularly the generation of a large peak torque due to an inertial force due to a rapid change in the rotational speed of each part at the end of a shift operation at the time of an upshift, deteriorates ride comfort. There is a problem.

To cope with this problem, for example,
As disclosed in Japanese Patent No. 96129, the shift shock or the shift shock is reduced by reducing the amount of fuel supplied to the engine during an upshift or by correcting the ignition timing to a retard side to reduce the engine output torque. There is one that suppresses the peak torque.

(Problems to be Solved by the Invention) By the way, the control for suppressing the shift shock as described above minimizes the decrease amount of the engine output torque and avoids the deterioration of the running feeling due to the decrease in the torque as much as possible. However, the shift shock is performed so as to be surely suppressed. Therefore, the amount of decrease in the torque may be controlled in accordance with, for example, a characteristic according to the throttle opening of the engine corresponding to the magnitude of the shift shock.

However, if this characteristic is fixed, or if the amount of decrease in the engine output torque during shifting is constant, there is a situation in which the slip of the drive wheels is likely to occur as in the case where the above-described traction control is performed. In this case, the amount of decrease in the engine output torque is relatively insufficient with respect to the magnitude of the shift shock, and the peak torque of the shift shock causes the drive wheels to slip, thereby impairing the slip elimination effect of the traction control. Will be. Also,
To prevent this, if the amount of decrease in the engine output torque during shifting is set to a large value in advance, the engine output torque will unnecessarily decrease during shifting in a normal operating state where traction control is not performed. As a result, the running feeling as described above is deteriorated.

Thus, the present invention reliably prevents a drive wheel from slipping at the time of shifting during traction control in a vehicle in which traction control and shift shock reduction control are performed, while avoiding deterioration in feeling during shifting during normal operation. Thus, an object is to improve the controllability of the traction control.

(Means for Solving the Problems) In order to solve the above problems, the present invention is characterized in that it is configured as follows.

First, the traction control device for a vehicle according to the invention described in claim 1 of the present application (hereinafter, referred to as a first invention) controls a predetermined driving force adjustment function so as to eliminate the slip when the drive wheels slip. Traction control means for suppressing driving force, and shift shock reduction for reducing engine output torque by controlling an engine output torque adjustment function different from the above-described drive force adjustment function so as to reduce shift shock during shifting of the automatic transmission. Means, and when the shift operation of the automatic transmission is performed during the operation of the traction control means, the reduction amount of the engine output torque by the shift shock reduction means is made smaller than the reduction amount during the shift in the normal operation state. Is also provided, wherein a correction means for increasing the size is also provided.

Further, a traction control device for a vehicle according to the invention described in claim 2 (hereinafter, referred to as a second invention) controls the throttle opening of the engine and the ignition timing so as to eliminate the slip when the drive wheels slip. Traction control means for suppressing the driving force of the automatic transmission, and shift shock reduction means for reducing the engine output torque by correcting the fuel supply amount so as to reduce the shift shock during shifting of the automatic transmission. When a shift operation of the automatic transmission is performed during the operation of the means, a correction means is provided for increasing a reduction amount of the fuel supply amount by the shift shock reduction means as compared with a shift in a normal operation state. And

Further, the traction control device for a vehicle according to the invention described in claim 3 (hereinafter referred to as a third invention) is characterized in that, in the first invention or the second invention, the shift shock reduction means at the time of shifting during the operation of the traction control means. Is set to a larger value as the throttle opening is larger.

Further, the traction control device for a vehicle according to the invention described in claim 4 (hereinafter referred to as a fourth invention) also has a first traction control device.
The invention or the second invention is characterized in that the reduction amount of the engine output torque by the shift shock reduction means during the shift operation during the operation of the traction control means is set to a larger value as the slip amount of the drive wheels increases.

(Operation) According to the above configuration, in any one of the first to fourth aspects of the present invention, when shifting while the traction control unit is operating, the reduction amount of the engine output torque by the shift shock reducing unit is controlled by the shift in the normal operation state. Therefore, when shifting in a normal driving state, deterioration of the running feeling due to unnecessarily lowering the engine output torque is avoided, and during traction control in which the slip of the drive wheels is likely to occur. At the time of gear shifting, the engine output torque is sufficiently reduced with respect to the magnitude of the gear shift shock, and slip of the drive wheels due to an insufficient amount of the reduction is reliably prevented.

(Example) Hereinafter, an example of the present invention will be described. In the following embodiment, when the driving wheel slips due to excessive driving force, the driving force is suppressed by applying a braking force to the driving wheel and the output torque of the engine is reduced as traction control. Accordingly, the driving force suppression control is performed.

As shown in FIG. 1, in the vehicle according to this embodiment, left and right front wheels 1 and 2 are driven wheels, left and right rear wheels 3 and 4 are driving wheels, and the output torque of the engine 5 is The power is transmitted to left and right rear wheels 3 and 4 via a propeller shaft 7, a differential device 8 and left and right drive shafts 9 and 10.

Each of the wheels 1 to 4 has a disk 11a to 14a that rotates integrally with the wheel, and a caliper 11b to 14b that brakes the rotation of the disk 11a to 14a by receiving a supply of braking pressure. Are provided, and a brake control system 20 for performing a braking operation of these brake devices 11 to 14 is provided.

The system 20 includes a booster 22 that uses a hydraulic booster that increases the depression force of a brake pedal 21 by a driver, and a master that generates a braking pressure in accordance with the depression force that is increased by the booster 22. And a cylinder 23. The brake pressure supply pipes 24, 25 for the front wheels led from the master cylinder 23 are connected to the calipers 11b, 12b of the brake devices 11, 12 in the left and right front wheels 1, 2, respectively. The front wheels 1 and 2 are braked by the applied braking force.

Further, the booster 22 includes a working pressure supply pipe 27 that supplies a working pressure from a pump 26, a working fluid return pipe 29 that returns excess working fluid generated by the booster 22 to a reservoir tank 28, and Are connected, and the first
The brake pressure supply pipe 30 and the second brake pressure supply pipe 31 branched from the pump discharge side of the working pressure supply pipe 27 are provided with electromagnetic first and second on-off valves 32 and 33, respectively. A one-way valve 34 is provided in the first brake pressure supply pipe 30 in parallel with the first on-off valve 32. Further, the first and second brake pressure supply pipes 3
0 and 31 are joined at a point X, and the left and right rear wheels 3,
The brake pressure supply pipes 35, 36 for the rear wheels are guided to the calipers 13b, 14b of the brake devices 13, 14 in 4, and on these brake pressure supply pipes 35, 36, electromagnetic on-off valves 37, 38, and electromagnetic relief valves 39 and 40 are also installed.

And, each of the on-off valves 32, 33, 37, 38 and the relief valve 39,
A traction control unit (hereinafter, referred to as TRCU) 50 for controlling the control valve 40 is provided, and the braking control signal a, b, c from the TRCU 50 opens the first opening / closing valve 32 as shown in FIG. The valve 33 is closed and the brake pressure supply pipes 35, 3 for the rear wheels
6 When the on-off valves 37, 38 are open, the booster 22
The braking pressure corresponding to the depressing force of the brake pedal 21 generated by the first brake pressure supply pipe 30 and the rear wheel brake pressure supply pipe 3
Brake devices 13 and 14 on left and right rear wheels 3 and 4 via 5,36
Are supplied to the calipers 13b, 14b, and the rear wheels 3, 4 are respectively braked by a braking force corresponding to these braking pressures.

Also, the TRCU 50 outputs wheel speed signals d, e, f, and g from wheel speed sensors 51 to 54 that detect the rotation speeds of the wheels 1 to 4, respectively.
And braking control for slipping of the rear wheels 3 and 4 is performed based on these signals d to g. When performing this control, the first on-off valve 32 is closed and the second on-off valve is closed.
33 opens and the operating pressure generated by the pump 26 increases the booster 22
The pressure is directly supplied to the rear-wheel braking pressure supply pipes 35 and 36 as a braking pressure without passing through the motor. Then, each of the wheel speed sensors 51
When the slip of the rear wheels 3 and 4 is detected from the signals d to g from the signals 54 to 54, that is, the rotation speeds of the rear wheels 3 and 4 as driving wheels are higher than the rotation speeds of the front wheels 1 and 2 as driven wheels. When it is detected that it has become large, the braking pressure supply pipes 35, 3
By opening and closing the on-off valves 37, 38 and the relief valves 39, 40 on the 6 by duty control, a braking force is applied to the rear wheels 3, 4 with a braking pressure according to a slip state.

In this embodiment, the control for suppressing the driving force when the rear wheels 3 and 4 slip is performed by controlling the ignition timing and controlling the throttle opening in addition to the control for applying the braking force as described above. The control is also performed by a control for lowering the output torque of the engine 5.
In response to the traction operation signal h from the engine 50, the engine 5
An engine control unit (hereinafter, referred to as an ECU) 60 for controlling the ignition timing and the throttle opening so as to reduce the output torque of the engine is provided.

The ECU 60 sets an ignition timing based on an engine speed and a throttle opening detected by a sensor (not shown), and ignites ignition plugs 61... 61 provided in each cylinder of the engine 5 at the ignition timing. The ignition timing control signal i is output to the igniter 62. The signal i causes the ignition plugs 61... 61 of the respective cylinders to be ignited through the ignition coil 63 and the distributor 64 at a timing corresponding to the operation state. In some cases, the ECU 60 corrects the ignition timing in the retard direction in accordance with a preset characteristic, whereby the engine output torque is reduced.

The ECU 60 is provided with an accelerator pedal operated by a driver when the traction operation signal h is input.
A throttle opening adjustment mechanism 68 interposed between a throttle valve 65 and a throttle valve 67 provided in an intake passage 66 of the engine 5.
Output a throttle control signal j. Normally, the throttle opening adjustment mechanism 68 opens and closes the throttle valve 67 in accordance with the amount of depression of the accelerator pedal 65.
When the control signal j is received from the ECU, the opening degree of the throttle valve 67 is reduced with a predetermined characteristic with respect to a constant accelerator pedal depression amount, whereby the engine output torque is also reduced. become.

Further, the ECU 60 calculates a fuel supply amount for each cylinder based on the intake air amount and the rotation speed of the engine 5, and controls the fuel injection valves 69 provided for each cylinder so as to achieve the calculated supply amount. A fuel control signal k is output to 69.

On the other hand, in the automatic transmission 6, switching of the gear position and operation of a lock-up clutch (not shown) are controlled by an automatic transmission control unit (hereinafter, referred to as ATCU) 70. The ATCU 70 sets a shift speed in accordance with an operation state indicated by, for example, the vehicle speed of the vehicle and the throttle opening of the engine 5, and is provided in the hydraulic control device 71 of the automatic transmission 6 so as to achieve the shift speed. The lock-up solenoid is locked to the lock-up solenoid valve 73 in the hydraulic control device 71 so as to output a shift control signal l to the gear-change solenoid valves 72... An up control signal m is output.

The ATCU 70 outputs a shift signal n to the ECU 60 at the time of shifting gears according to the shift control signal l, that is, at the time of shifting, and the ECU 60 receives the fuel injection valve 69 when the shift signal n is input. The fuel control signal k is output so as to decrease the fuel supply amount of the fuel cell 69..., Whereby the engine output torque is reduced according to a predetermined characteristic during gear shifting.

Next, the specific operation of the engine output torque reduction control during gear shifting by the ECU 60 will be described with reference to the flowchart shown in FIG.

First, ECU 60 determines whether or not the traction actuation signal h is input from TRCU50 in step S _1, the signal h
When but not entered, that is, when in the normal operating state, in step S _2, the preset map shown in FIG. 3, the engine output torque during the gear shift in the normal operation state shown by the solid line Read the decrease. This map is set such that the larger the throttle opening, the larger the amount of decrease in the output torque.

Then, ECU 60 determines whether the shift signal n is input from ATCU70 Step S _3. Then, perform the steps S ₄ when the signal n is input, the fuel injection valves 69 ...
69 outputs a fuel control signal k, only the engine output torque amount read from the map in the step S ₂ reduces the fuel supply amount to decrease.

As a result, the engine output torque is reduced during gear shifting, and shift shock is reduced. In this case, the shift shock increases as the throttle opening at that time increases, but the amount of reduction in the engine output torque increases accordingly, so that the shift shock is always effectively reduced. . In particular, since the amount of decrease in the engine output torque in this case is relatively small as shown in FIG. 3, deterioration of the feeling at the time of gear shifting caused by reducing the torque more than necessary is avoided. .

On the other hand, when the traction operation signal h is input from the TRCU 50 to the ECU 60, the ECU 60 performs a retard correction of the ignition timing, a decrease correction of the throttle opening, and the like in order to eliminate the slip of the rear wheels 3, 4. together, step S ₅ from step S ₁
To read the amount of decrease in the engine output torque during gear shifting during the traction control indicated by the broken line in the map of FIG. In this case, the amount of decrease in engine output torque during shifting during this traction control is set to increase as the throttle opening increases and as the slip amount of the rear wheels 3 and 4 increases. , Is set to be larger than the amount of reduction at the time of shifting during the normal operation.

Then, ECU 60, together with the shift signal n from ATCU70 in step S ₆ is determined whether or not the input, executes step S ₇ when the signal n is input, the step S ₅
The fuel control signal k is output to the fuel injection valves 69... 69 to reduce the fuel supply amount so that the engine output torque is reduced by the amount read in. The number is larger than during normal operation.

As a result, when traction control is performed,
In other words, when the rear wheels 3 and 4, which are the drive wheels, are likely to slip, the engine output torque is sufficiently reduced with respect to the magnitude of the shift shock during shifting, and the shift shock is reduced. Is effectively reduced, and at the same time, the slip of the rear wheels 3, 4 due to the peak torque of the shift shock caused by the relative shortage of the engine output torque is reliably prevented.

(Effects of the Invention) As described above, according to the traction control device of the present invention, in a vehicle in which the engine output torque is reduced during a gear shift to reduce the gear shift shock, the engine for reducing the gear shift shock is provided. Since the amount of decrease in the output torque is made larger during shifting in the traction control state than during shifting in the normal operation state, the drive wheel due to a shift shock during shifting during traction control in which the drive wheel is likely to slip. Is reliably prevented, and at the time of gear shifting in the normal operation state, deterioration of the traveling feeling due to unnecessarily lowering the engine output torque is avoided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention. FIG. 1 is a system diagram of a traction control device, FIG. 2 is a flowchart showing a control operation at the time of shifting, and FIG. It is an explanatory view of a map used in. 3, 4 ... drive wheels (rear wheels), 5 ... engine, 6 ... automatic transmission, 50 ... traction control means (traction control unit: TRCU), 60 ... shift shock reduction means, correction means (engine control unit: ECU)

Continuation of the front page (51) Int.Cl. ⁶ identification code FI F02D 43/00 301 F02D 43/00 301H 301K F02P 5/15 F02P 5/15 F (72) Inventor Takayuki Sakai Shinchi 3 Fuchu-cho, Aki-gun, Hiroshima Prefecture No. 1 Inside Mazda Co., Ltd. (56) References JP-A-2-40035 (JP, A) JP-A-57-22948 (JP, A) JP-A-56-96129 (JP, A) JP-A-3 -202646 (JP, A) JP-A-64-16446 (JP, A) Patent 2526706 (JP, B2) JP 7-99096 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB Name) F02D 29/00-29/06 F02D 41/00-41/40 F02D 43/00-45/00

Claims (4)

(57) [Claims] A traction control means for controlling a predetermined driving force adjusting function to suppress a driving force so as to eliminate the slipping of a driving wheel, and to reduce a shift shock at the time of shifting of an automatic transmission. A shift shock reducing means for controlling an engine output torque adjusting function different from the driving force adjusting function to reduce the engine output torque, and a shift operation of the automatic transmission during the operation of the traction control means. A traction control device for a vehicle, further comprising a correction means for increasing an amount of decrease in engine output torque by the shift shock reduction means as compared with a shift in a normal operation state. 2. A traction control means for controlling a throttle opening of an engine and an ignition timing to suppress a driving force so as to eliminate a slippage of a driving wheel, and reducing a shift shock during a shift of an automatic transmission. Transmission shock reduction means for correcting the fuel supply amount to reduce the engine output torque, and when the automatic transmission performs a shift operation while the traction control means is operating. A traction control device for a vehicle, further comprising a correction unit that increases a correction amount of a decrease in a fuel supply amount by a shift shock reduction unit compared with a shift in a normal operation state. 3. The method according to claim 1, wherein the reduction amount of the engine torque by the shift shock reducing means during shifting while the traction control means is operating is set to a larger value as the throttle opening increases. Item 3. A traction control device for a vehicle according to item 2. 4. The system according to claim 1, wherein the reduction amount of the engine output torque by the shift shock reduction unit during the shift operation during the operation of the traction control unit is set to a larger value as the slip amount of the drive wheels increases. The traction control device for a vehicle according to claim 1 or 2.