JPS63309746A - Controller for slip of driving wheel - Google Patents

Abstract

PURPOSE:To prevent after-fire and improve performance by suspending the fuel supply in the first prescribed period in the excessive slip state of a driving wheel and increasing the fuel supply in the second prescribed period after the stop of fuel feed. CONSTITUTION:A vehicle 1 is set, for example, into front wheel drive type, and speed sensors 21-24 are installed individually onto the right and left driving wheels 11 and 12 and the right and left trailing wheels 13 and 14. Each detection signal supplied from the speed sensors 21-24 is calculation-processed in an ECU 35, and a plurality of fuel injection valves 36 of an engine 31 are controlled according to the result, and the excessive slip state of each driving wheel 13, 14 is controlled. In this device, in the first prescribed period in the excessive slip state of each driving wheel 13, 14, the fuel injection from each injection valve 36 is suspended. In the second prescribed period after the stop of the fuel injection, the fuel quantity supplied from each fuel injection valve 36 is increased.

Description

[Detailed description of the invention]

(Field of Application of Industry-1-) The present invention relates to a drive wheel slip control device for a vehicle, and particularly to a control device that performs appropriate slip control when the drive wheels transition to an excessive slip state. (Prior art and its problems) In general, when a vehicle starts or accelerates, the driving force of the drive wheels is affected by the friction force between the tires and the road surface [friction coefficient between the tires and the road surface x the load on the drive wheels of the vehicle weight (11 (Cargo City)], the drive wheels will slip, but the slip ratio λ representing the degree of slip is calculated by the following equation (1), where Vw is the circumferential speed of the drive wheels and V is the speed of the vehicle. λ = (Vw - V) / Vw - (]) Depending on this slip ratio λ, the frictional force between the tire and the road surface (that is, the limit value of the driving force of the drive wheels) changes as shown in Figure 8. , this frictional force reaches its maximum at a predetermined value λ0.Furthermore, the frictional force between the tires and the road surface is the frictional force in the direction of vehicle travel (vertical direction), but the frictional force in the lateral direction (lateral force) is As shown by the dotted line in the figure, the slip ratio decreases as the slip ratio λ increases.Based on this point, the longitudinal friction force between the tires and the road surface is maximized to maximize the vehicle drive efficiency, and For example, Japanese Patent Publication No. 52-35837 discloses a slip prevention device for preventing a vehicle from rolling sideways by suppressing a decrease in lateral frictional force as much as possible. The wheel speed is controlled to prevent excessive wheel slippage by changing the driving torque of the engine by switching the ignition device on and off or switching the supply and cutoff of fuel f1 to the engine. Because of this, the engine's driving force always suddenly decreases immediately after the drive wheels shift from normal slip to excessive slip, causing the occupants to experience a shock, resulting in poor drivability.
1 ■ It had a problem. In addition, although the engine's combustion characteristics change depending on the engine speed, the conventional device described above does not control the engine's combustion characteristics accordingly. It is difficult to properly control
By controlling the amount of unburned fuel, 1 liter of unburned fuel is
'・1 is likely to be burned, and when a three-way catalyst is installed in the tJl gas system as a tll gas conversion device, the temperature of the three-way catalyst must be -1-JT. Performance deteriorates. Furthermore, since the amount of engine driving force differs depending on the size of the engine load, as in the above fjf technology, the engine load and 7+! ': When performing slip control in relation to When set to 1, the control is insufficient in high-load operating conditions, and therefore the drive wheel slip ratio can be adjusted to the desired value over the entire range of engine loads, resulting in good drivability. The problem is that it cannot be guaranteed. (Objective of the Invention) The present invention has been made in order to solve the problems of the prior art described in "-", which include the occurrence of afterfire when the drive wheels shift to an excessive slip state, and the three-way catalyst of the IJI gas system. It is an object of the present invention to provide a drive wheel slip control device that can prevent performance deterioration of a three-way catalyst caused by temperature JJ and improve engine drivability. (Means for Solving the Problems) In order to achieve the above objects, the present invention provides a fuel supply means for supplying fuel to an engine according to the operating state of the engine, and a means for controlling excessive slip of drive wheels of a vehicle. In a drive wheel slip control device comprising an excessive slip detection means for detecting an excessive slip state, and an engine output reduction means for reducing engine output when the excessive slip detection means detects an excessive slip state, the engine output reduction means is configured to fuel supply stop means for stopping the supply of fuel oil from the fuel supply means for a first predetermined period when an excessive slip condition is detected;
The fuel when the excessive slip state is detected (second predetermined period after the end of supply stop, 0; (Embodiment) Hereinafter, embodiments of the present invention will be explained with reference to the drawings. Fig. 1 shows a vehicle equipped with the driving wheel slip control device of the present invention. 1, the vehicle 1 is, for example, a front wheel drive type, with front wheels 11.12 serving as driving wheels driven by an internal combustion engine 31, and rear wheels 13.14 serving as driven wheels. As will be clear from the following description, the present invention can be applied to rear-wheel drive vehicles in exactly the same way.) +'+ij Driving wheels 11, I2 and driven wheels 13.1
4 includes six drive wheel speed sensors 21, 22 and driven wheel speed sensors 23, 24, and the left and right drive wheel speeds ω'11 are determined by the drive wheel speed sensors 21, 22.
,ωF+! is detected, and the driven wheel speed sensor 2
According to 3.24, the left and right driven wheel speed ωI! 14, ωI! P
are detected, and these detection signals are input to an electronic control unit (hereinafter referred to as rECUJ) 35. In this embodiment, the ECU 35 constitutes an excessive slip detection means, a fuel supply stop means, and a fuel oil '1 reduction means. 1EcU35 is the left and right driving wheel speed ωFL as described later.
, ωFR is selected and the formula (1)
Let the driving wheel speed Vw be the driving wheel speed ωI on the same side as the driving wheel speed ωFL or ωFR selected in 1. 1. Alternatively, by setting ωRR to the vehicle speed V in the above equation (1), calculate the slip rate λ using the following equation (c).Furthermore, the ECU 35 calculates the amount of change (differential value) of the slip ratio λ.This amount of change ^ is a digital value. In the control, the difference for each calculation processing cycle is used instead.In addition, the transmission 16 interposed between the engine 31 and the drive wheels 11 and 2 is equipped with a sensor (not shown), and the The transmission signal is input to the ECU 35.The ECU 35 controls the output of the engine 31 using a fuel supply control device, which will be described later.
The slip state of the drive wheels 11, 12 is controlled by controlling the torque of the drive wheels 11, 12. FIG. 2 is an overall configuration diagram of the n1j memory combustion 1"l II supply sub-control device, and the internal combustion engine 31 has, for example, six cylinders (M
Furthermore, an intake pipe 32 is connected to the engine 31. A throttle body 33 is installed in the middle of the intake pipe 32, and a throttle valve 33' is provided inside.
l+) sensor 34 is connected to convert the opening degree of the throttle valve r33' into an electrical signal and send it to the ECU 35. 1. Between the engine 31 and the throttle body 33 of the intake pipe 32, there is a fuel 1'1 injection pipe (fuel supply) to each cylinder fσ, and to the 1st flow side of the intake valve (not shown) of each air 1i'li. means) 36 are provided. The fuel injection valve 36 is connected to a fuel 1'-1 pump (not shown) and electrically connected to the 1zCU 35, and the valve opening time of the fuel 1'-1 injection valve r36 is controlled by a signal from the ECU 35. . On the other hand, the throttle valve 33' of the throttle body 33
The intake pipe absolute pressure (PH^) is connected to the downstream side of the intake pipe through a pipe 37.
A sensor 38 is installed, and this absolute pressure sensor 38
The absolute pressure signal converted into an electrical signal by the EC
Sent to U35. The engine 31 body has an engine cooling water temperature sensor (hereinafter referred to as "
Go W Senza) 39 was established (Zurare, Go W Sen 1)
39 consists of a thermistor, etc., and is inserted into the circumferential wall of the engine cylinder filled with cooling water, and the detected water temperature signal is transmitted to the ECU.
35. An engine rotation speed sensor (hereinafter referred to as rNe sensor) 40 is mounted around a camshaft (not shown) or crankshaft of the engine, and the Ne sensor 40 is set at a predetermined crank angle position every 120° rotation of the engine crankshaft. The crank angle position signal pulse (hereinafter referred to as "'I" II) is a pulse at a crank angle position before a predetermined crank angle with respect to the dead center (TI) C) at the start of the intake chamber 111' of each cylinder. "), and this T'DC signal pulse is
Sent to 5. A three-way catalyst 42 is disposed in the υ1 trachea 4I of the engine 31, and performs a purifying action on 1-IC, Go, and NOx components in the exhaust gas. 0 on the upstream side of the three-way catalyst 42 in the exhaust pipe 41
A 2 sensor 43 is inserted, and this sensor 43 detects the oxygen concentration in the exhaust gas and supplies a 02 concentration signal to the 1ECU 35. Furthermore, the ECU 35 has i'l:J driving wheel speed sensor 2.
1.22, the driven wheel speed sensor force 23, 24, and other parameter sensors 44, such as the sensor for detecting the gear ratio of the transmission 16, are connected, and each of these pressure sensors The value is supplied to the ECU 35. 17, CtJ35 is various sensors (Nii drive wheel speed sensor 1.22, driven wheel speed 11 sensor 2: 3.24)
and +'+f transmission (including the 6th sensor force) Rokuryoku Shinkyu waveform is shaped, the voltage level is corrected to a predetermined level,
An input circuit 35a having functions such as converting analog signal values into digital signal values, a central processing circuit (hereinafter referred to as rc);
PIJ") 35b, a storage means 35c for storing various calculation programs and calculation results executed by the CPU 35b, and an output circuit 35d for supplying a drive signal to the fuel injection valve r36. Each time the TDC signal pulse is input, the CPU 35b calculates the fuel injection time Tou'r of the fuel injection valve 36 based on the following formula in response to engine parameter signals from the various sensors described above supplied via the input circuit 35a. do. TOUT= TiX (KTW −KPA −KSTB
-Kwot ・1(LS ・I(AST-Krn-K
o2) 10 (TACC+TIDL) = 43) Here, TI is a reference value for the injection time of the fuel injection valve 36, and is determined according to the engine rotational speed Ne and the absolute pressure in the intake pipe 1) RA. Krw is a water temperature increase coefficient applied for the purpose of ensuring an appropriate air-fuel ratio for early warm-up when warming up the engine 31, and is determined according to the engine water temperature Tw. KPA is an atmospheric pressure correction coefficient determined according to atmospheric pressure. K.S.
TB is a correction coefficient for slip control, which is determined according to the slip ratio λ, the slip rapid change amount λ, etc., as described later. KWOT is the enrichment coefficient of the air-fuel mixture when the throttle is fully open, KLS is the lean coefficient of the mixture when the throttle is fully closed, and KAS is the fuel increase coefficient after starting. pH is a + load correction coefficient determined according to the change in the absolute pressure Pn△ in the intake pipe, and 1 (02 is the 02 feedback correction coefficient determined according to the output of 43.'I '8c,'l''IIIL is)lli positive variable square number, 1); The first is the acceleration increase variable applied when the engine 31 accelerates, the latter is the idle applied when J3 is in the idle area of the engine 31. It is a correction variable. The CPU 351) sets the fuel injection valve p36 corresponding to the cylinder in which the intake stroke of the engine 31 starts based on the fuel injection time 1''outT obtained as described in -1- above.
A drive signal for adjusting II, /ffl is supplied to the fuel injection valve p3G via the output circuit 35d. FIG. 3 is a logic circuit diagram showing the (1η configuration) of the main part of the CPU 35L+ in FIG.
9 is the detected driven wheel speed ωF! shi, the average of ωPR @(coP
t±ωgFri/2 is calculated, and the average multiplex discrimination circuit 50 outputs an output signal representing the average value (ωRL + ωR1ri/2) and a judgment value VhrN (for example, 5 km/h) indicating whether the vehicle speed is extremely low.
), and if it is determined that the latter is larger, that is, if the average vehicle speed is lower than the discrimination value VMIN, a high level signal (hereinafter referred to as "1-1 signal") is In this case, the low level signal (hereinafter referred to as rL times signal)
is output to the drive wheel speed selection circuit 5). The driving wheel speed selection circuit 51 selects the detected driving wheel speed ωFL, 6.
) Among F and R, when the output signal from the average overlap discrimination circuit 50 is an I-(signal, that is, when the vehicle speed is in an extremely low speed range, the one with the smaller value, that is, the one indicating a low wheel speed is selected. When the output signal is the L signal, that is, when the vehicle speed is not in the extremely low speed range, the larger value
That is, the one showing a higher wheel speed is selected (high selection method), and the selected detected driving wheel speed (zl F L
Alternatively, let ωFR be the driving wheel speed Vw in the above equation (1). The driven wheel speed selection circuit 52 selects the detected driven wheel speed ωI! 11,
Among ωRR, the one on the same side as the detected driving wheel speed ωFL or 0)FR selected by the tf'l nQ Ig driving wheel speed selection circuit 51 is selected, and the selected detected driven wheel speed ωR is selected.
Let L or ωRR be the vehicle speed V in the above equation (1). By the output signals from these selection circuits 51 and 52,
The slip rate calculating circuit 53 calculates the slip rate λ based on the 0;j notation (2). A differentiation circuit 54 calculates a differential value of the slip ratio based on the output signal from the slip ratio calculation circuit 53. Further, the setting circuit 60 sets the transmission 16 to 0iit.
Based on the gear ratio, a correction coefficient + and a correction variable G+ corresponding to the first threshold value λ1 of the slip ratio are added to the gear ratio output from the sensor obtained. 1 to the threshold value λ2 of 2. ); 2 and correction variable C2 for the jF coefficient, and correction coefficient rl and correction variable F+ for determining the first slip ratio change amount base value λl;
Based on the second slip ratio change amount, a correction coefficient r2 and a supplementary variable F2 are set according to the 1: value ^2. Note that the correction coefficients r1, F2 and the correction variables F1, F2 are corrected and set according to the control delay from the time when an operation command is issued to the fuel supply control device until the device actually operates. The first speed calculation circuit 61 receives an output signal representing the vehicle speed V from the driven wheel speed selection circuit 52, and sets a correction coefficient of 1 and a correction variable 01 according to the first threshold value λ1 of the slip ratio from the setting circuit 60. A first predetermined speed value VRI is determined based on the output signal represented by the following equation. VR+= +V+C, + - (4) The relationship between the slip rate and the first threshold value λ1 at this time is:
λ+=(VR+-V)/VRI. Furthermore, the first speed calculation circuit 61 calculates the calculated first predetermined speed value Vg+
and the first speed lower limit value Vc+, and the larger value of both is set as the first base 711; speed value corresponding to the first threshold value ^1 of the slip ratio. Further, the second speed calculation circuit 62 responds to the output signal from the driven wheel speed selection circuit 52 and the second threshold value λ2 of the slip ratio from the setting circuit 60, similarly to the first speed calculation circuit 61 of nIJ. 2 and the correction variable C? The second predetermined speed (1
1'(V l!2 is determined, and the second predetermined speed value VC5
! 2 and the second speed limit value VC2, the larger value is set as the second base 41 corresponding to the second threshold value λ2 of the slip ratio:
Let it be the speed value. ■! ! 2- to 2V + C2 (5) The first correction circuit 65 receives the output signal from the driven wheel speed selection circuit 52 and the first correction signal determined for each gear ratio from the setting circuit 60.
Correction coefficient r1 according to the slip rate change speed basic value 1+
and the output signal representing the correction variable F1, the following equation (6) is obtained.
Based on the first slip ratio change amount reference value ^1, the vehicle speed V
Correct accordingly. ^+=r-+V+F+ (6) Similarly to the first correction circuit 65 described in i'lij, the second correction circuit 66 receives the output signal from the driven wheel speed selection circuit 52 and the setting circuit 60. Correction coefficient r according to the second slip ratio change speed base 41J value ^2 determined for each gear ratio
2 and the complementary i[゛The output signal representing the variable 112 is based on the following equation (7), the second slip ratio change reference value λ2
is corrected according to the vehicle speed V. ^2=r2V4-F2- (7) - The first slip rate mentioned above. Second threshold value λ1. λ
2 and 1st. Second slip ratio changing claw reference value λ1. λ2
are λ1×^2 and λ1〈λ at any gear ratio.
It is set so that the following relationship 2 is satisfied. The excessive λ determination circuit 55 receives the output signal l from the differentiating circuit 54,
The output signal representing the second base 1111i value λ2 from the second correction circuit 66 is compared with the differential value λ of the slip ratio.
When it is determined that the value is larger than the reference value λ2, the OR circuit 56
11 signals are output via the signal, and in other cases, an L signal is output. The first predictive control determination circuit 58 compares the output signal from the differentiating circuit 54 and the output signal representing the first base r111 value 1 from the first correction circuit 66, and calculates the differential value λ of the slip ratio.
When it is determined that is thicker than the first reference value ^1, AND
An II times signal is output to the circuit 59, and in other cases, an L signal is output. The second child 4 (11 control determination circuit 63 compares the output signal from the drive shaft speed selection circuit 51 and the output signal from the first speed calculation circuit 61, and determines whether the drive wheel speed Vw is the first of the slip ratios. The first group 71g corresponding to the threshold value λ1 of
When it is determined that the speed is greater than the speed value, 1 is sent to the AND circuit 59.
-1 signal, otherwise,

[, outputs a signal. When the A N D circuit 59 receives the 14 signals from both the first and second predictive control determination circuits 58 and 63, the A N D circuit 59 performs an OR operation.
11 signals are outputted via the circuit 56. The excessive λ determination circuit 64 compares the output signal from the drive wheel speed selection circuit 51 and the output signal from the second speed calculation circuit 62, and determines that the drive wheel speed Vw is at the second threshold value λ2 of the slip ratio. When it is determined that the speed is greater than the second reference speed value corresponding to , the I-1 signal is outputted via the OR circuit 56. As shown above, i) ^>x2 (excessive slip rate speed prevention), (ii) i>;c= and λ>λ1 (predictive control)
or (iii) λ>λ2 (excessive slip rate 11/j
If any of the conditions in Jl2) is satisfied, It Shinsou is output via the OR circuit 56, and in this case, a twisting cut (hereinafter referred to as [Fuconil cut]) as described later is performed.
By executing this and reducing the torque of the drive wheels 1] and 12, the slip ratio λ or the slip ratio change speed λ is decreased, and the slip ratio λ is controlled to a desired value. Below, OR
The II-fold signal output from the circuit 56 is called a fuel cut signal (FCM signal) ((b) (1) in FIG. 5), and the driving range of the vehicle 1 where the fuel cut I signal is in the on state is a fuel cut signal. It is called the area ((C) in Figure 5) (
])). The signals of the first and second predictive control determination circuits 58 and 63 are also output to an OR circuit 67, and the OR circuit 67
and when at least one of the output signals of the second predetermined δ1 control determination circuits 58 and 63 is an I+ times signal, that is, ^>
J1 signal is output when either the condition λ1 or λ〉oil is satisfied. Hereinafter, the signal output from the OR circuit 67 will be referred to as a standby signal (STB signal).
(b) (2) in the figure, the driving area of the vehicle 1 in which the standby signal is in the on state and the -11 fuconyl cut signal is in the off state is the standby area ((c in Fig. 5)).
(2)), the area other than the standby area and the fuconyl cut area is referred to as the off-standby area ((c)(3) in Figure 5).The standby area is the off-standby area. Setting conditions (i>λl or λ
〉λ1) and setting conditions for the fuconyl cut region (〉λ1)
As is clear from the above (I JI λ〉λ1, etc.), immediately before the vehicle 1 transitions from the off-standby area, which is the normal driving area, to the fuel cut area where fuel cut is to be performed, or vice versa, This corresponds to the operating region ((a) and (C) in FIG. 5). The purpose of setting such an operating region is to appropriately control the amount of fuel supplied to the engine 31 in the region as described later, and to control the air-fuel mixture when passing between the normal operating region and the fuel cut region. By appropriately changing the air-fuel ratio, the driving force of the engine 31, etc., it is possible to increase the temperature of the three-way catalyst 42 and help generate afterfire, and also to prevent driving shock.
This is to improve drivability by I and the like. Also, the j-th Jl (speed determination circuit 68) (speed setting circuit 5
Output (R, first predetermined value V+
(for example, 12 km/h), and when the latter is greater than the former, that is, when V>Vl holds, a first multiplex discrimination signal (FCM+ signal) is output. Furthermore, the second vehicle speed determination circuit 69 also has the same function as the first vehicle speed determination circuit 68.
Similarly, a signal representing the vehicle speed V and the first predetermined value V1
A reference signal representing a larger second predetermined value V2 (for example, 20 km/h) is compared, and when V<V2 is established, a second multiplex determination signal (FCM2 signal) is output. FIG. 4 is a control program for performing slip control according to the generation states of the fuel cut signal, standby signal, etc. outputted by the logic circuit of FIG. 3 and other operating parameters, and this program 4J: T D
Executed every time a C signal pulse occurs. First, in step 401, it is determined whether a standby signal is input. If the answer is negative (No), that is, the standby signal is not input and therefore the vehicle 1 is in the off-standby region, the step/
Proceeding to I02, it is determined whether the second flag FLGpcr2 is equal to O or not. This second flag F L C;
FCT2 is set to 1 in step 9, which will be described later, when a standby signal is input, that is, when the vehicle @1 is in the standby region or the fuel cut region, and when the vehicle 1 is in the off-standby region, This is set to O in step 6, which will be described later. If the answer to step 402 is negative (No), that is, the second flag FLG FcT2 is equal to 1, and therefore the current loop is the loop immediately after transitioning to the off-standby region, the process proceeds to step /103. In this step 403, the timer T and TRC consisting of down counters are set to Tyc (for example, 2.0 seconds) for a predetermined period of time, and are started. Then, in step 40
In step 4, it is determined whether the engine speed Ne is greater than a predetermined number of times NeTIIC (for example, 2.300 rpm). The answer to this step 404 is 11 constant (Yes), that is, Ne
〉NeT+! When c holds true, the process proceeds to step 405, where the third control variable CLJ rer3 is set to a fifth predetermined number of times N4 (for example, 2), and then step 406
In J3, the slip control correction coefficient KSTB is set to a lean predetermined value X5TB2 (for example, 0
, 8) (section A of (d) (3) in FIG. 5). Next, the process proceeds to step 406a, where the water temperature increase coefficient Krw is set to a predetermined value KTILIO, and then step 411 described below
Proceed to. FIG. 7 shows the predetermined value KTI depending on the engine water temperature Tt+r.
An example of a KTILIO table for setting LIO is shown. That is, according to the figure, the predetermined value Krwo is one of three boundary values TIL11 to Tw* at an engine water temperature of 1゛W.
(e.g. -10°C1+20°C and +50°C respectively)
From the relationship, if the engine water temperature Tw is less than Tw+ or Tw
3 or more, the first predetermined value KTuro+ (for example, 1.00) is set, and when it is Tw+ or more and less than Tll+2, the second predetermined value KTWO2 (for example, 0.90) is set to 1゛W.
2 or more and less than ITw3, the third predetermined value KTIL10
3 (for example, 0.95). When the answer to the step 407I is negative (No), that is, when the engine rotation speed Ne≦predetermined rotation speed Neyic holds true, the process proceeds to step 407, and the third control-23=value O is set in the variable CU FCT3. Then, in step 408, the slip control correction variable KsrB is set to 1.
．． Set to 0 (section B of (d) (3) in FIG. 5), and proceed to step 4]1. If the answer to the step 402 is affirmative (Yes), that is, the second flag FLC; It is determined whether the third control variable CUrcr* is equal to O. If the answer to this step 409 is negative (No), that is, the third control variable CLIrcT:+ is not equal to O, then in step 410 the third control variable CUrcr* Count number of CUFCT3
subtract the value l from , then execute step 406 and proceed to step old1. When the answer to step 409 is affirmative (Yes), that is, the third control variable C: UFCT3 is equal to O, step 408 (1);j is executed and the process proceeds to step old 1. As shown in -1- below, when the engine speed Ne is large immediately after the vehicle shifts to the off-standby region, the 1i positive coefficient K S T g for slip control is changed to the fifth 1' ID C number of times equal to the predetermined number of times N+ is set to a value smaller than the subsequent normal value (
(d) (1) in Figure 5). As a result, the air-fuel mixture supplied to the engine 31 is made lean at the beginning of the release of the fuel cut, and the output of the engine 31 is reduced compared to the normal output in this region, so that the shock caused by the rapid recovery of the driving torque is reduced. It can be prevented. Furthermore, the reason why two-part lean is not performed when the engine speed Ne is small is to prevent engine stall. Note that instead of the two-part lean process, control may be performed to delay the ignition timing. Engine 31 due to delay in ignition timing
Since the output is reduced, in this case as well, the same effect as in lean storage can be obtained. Next, the process advances to step old 1, and the timer T set in step 403, the count value T of TRC, TRC7'
Determine whether J<0. This answer is negative (N
o), that is, the count value T, 'J'RC is not equal to O, and therefore the predetermined time Ll'l! after transitioning to the off-standby region! If e has not elapsed, the third flag F L G is set in step old 2 and step 413.
FCT3 and the fourth flag FLGFCT4 are each set to l, and the process proceeds to step old 6, which will be described later. If the answer to step 411 is affirmative (Yes), that is, the timer values T, T''RC are equal to 0, and therefore the predetermined time LTRC has elapsed since the transition to the off-standby region, in step 414 and step old 5, the rc13 to the third flag P L, fourth flag F l
, G FCT4 to O respectively, and then proceed to step 416. In step old 6, the second flag F L G FCT
2 is set to O, and then the first flag FLGpcT+ is set to O in step 7, the process proceeds to step 418, and the slip control correction coefficient KSrn set in step 406 or step 408 is calculated using the equation (3).
is applied to calculate the fuel f1 injection time 1'01JT, perform fuel injection based on the injection time 'T' o UT,
Exit this program. If the answer to step 401 is 11r (Yes), that is, the standby signal is input and the vehicle is in either the standby region or the fuel cut region, the process proceeds to step 9, where the second Set flag FLGFCT2 to 1. Next, the process proceeds to step 420, where a predetermined value X5TB for the standby area and a predetermined value Xr*c for the fuel cut area are set.
, the first and second predetermined times N01N1 are selected from the X5rn table, the Xr*c table, the NO child table, and the N1 table stored in the storage means 35c, respectively, according to the engine rotation speed Ne. Figures 6(a) to 6(d) show examples of these tables.
It is divided into five areas by e, and teX5T for each area.
B, XTRC, No. and N1 are each set as constant values. That is, the boundary values of the engine speed Ne are Ne+, Ne2, Ne3, and Ne4 (for example, 2.300.2.800.3, respectively) in descending order of the engine speed Ne.
300 and 4,800 rpm), engine speed Ne is less than Ne1, Ne+ or more than JxNe2, Ne2
J2 less than Ne3, NCl3 or more but less than Ne4, and Neq
Hereinafter, the areas 1 will be referred to as areas I, ①, III, IV, and V, respectively. The predetermined values X5TB for the standby region are XST+11, X5Tl+2, X, 5T113, X5 in order from the region I side, that is, from the low rotation region side, for regions 1 to V.
TB4 and X5TB5 (e.g. 0.50.0 each
．． 60.0.80.0.80 and 1.70) are set. Similarly, the predetermined value XTRC1 for the fuel cut region and the second predetermined number of times N01N+ are also set to the region 1-V.
On the other hand, in order from the region I side, all values for XTlIC are smaller than 1 (7) XTIICl ~ X, TlI
C5 (for example 0.35.0.40.0.40.
0.45 and O), but for NO, No+~No5(
For example, 1.2.3.4 and 255, respectively), and for N1, N++ to N15 (for example, 1.2.3.4 and 255, respectively).
3 and O) are set. These tables are based on engine characteristics and three-way catalyst 4.
It can be set in various ways depending on the type of item 2, etc. Next, the process proceeds to step /121, where it is determined whether or not a fuel cut signal is being input. This answer is negative (N
o), that is, the fuel cut signal is not input,
Therefore, when the vehicle is in the standby area, the process proceeds to step 422, where it is determined whether the third flag FLGpcr* is equal to 0 or not. If the answer to this step 422 is affirmative (Yes), that is, the third flag FLGpcr3 is equal to O, the fourth flag FLGFCT4 is set to 0 in step 423, and if the answer is negative (No), that is, the third flag FLGFCT3 is equal to 1. If it is equal to , the fourth flag FLGpcr is set to 1 in step 424, and then the process proceeds to step 425. In this step 425, all correction coefficients other than the atmospheric pressure correction coefficient KP^ among the correction coefficients applied to the equation (3) are set to 1.0, and all correction variables are set to O. This cancels these correction coefficients and correction variables. This makes it possible to eliminate the influence of fluctuations in these correction coefficients and correction variables on the fuel injection time T''OUT, so in steps 426 and 427 described later, the slip control correction coefficient sTl'I and the water temperature increase coefficient K
Coupled with the fact that rw is set again, engine 3
The air-fuel mixture supplied to No. 1 can be adjusted to the optimum desired air-fuel ratio. Therefore, the 4Jl output of unburned lyL fuel 1'1 is reduced, thereby preventing the occurrence of afterfire and performance deterioration of the three-way catalyst 42 due to the temperature of the three-way catalyst 12. In addition, the atmospheric pressure correction coefficient KP
The reason why ^ is not canceled is because this coefficient is set to t'JIl in order to prevent the air-fuel ratio of the mixture supplied to the engine 3I from changing due to changes in atmospheric pressure, so it is not canceled even in the standby region. This is because it is necessary to apply this coefficient in the same way as in the standby area. Next, the process proceeds to step 426, where the slip control correction coefficient K
syn is set to the predetermined value X STB for the standby area set in step 420 ((
d) Section C of (3)). During the transition between the off-standby area, which is a normal operating area, and the fuel cut area, where a fuel cut is performed as described later, the engine 3
The air-fuel ratio of the air-fuel mixture supplied to the three-way catalyst 42 is likely to fluctuate, and as a result, the combustion characteristics of the engine 31 become unstable, and a large amount of unburned fuel U1 is emitted, causing the temperature of the three-way catalyst 42 to decrease by -1. -H and afterfire are likely to occur. Further, the fuel characteristics of the engine 31 vary depending on the engine rotation speed Ne. Furthermore, in the low rotational speed range of the engine 31, a resonance phenomenon related to the suspension of the vehicle body occurs, which tends to deteriorate driveability. Therefore, as described above, by using the predetermined value X5TB for the standby region set according to the engine speed Ne as the slip control correction coefficient, the temperature of the three-way catalyst can be adjusted over the entire range of the engine speed. The occurrence of shoulders and afterfire can be prevented, and drivability can be improved. Note that the predetermined value X5TR for the standby area is set to the high rotation side (
In region V) of FIG. 6, the air-fuel mixture is enriched to 1.0 or more, but this is because the cooling effect of the three-way catalyst 42 is reduced by the heat of vaporization of the unburned components that increases as the air-fuel mixture becomes richer. This is because the temperature is accelerated and the temperature can be prevented from rising. Predetermined value X5 for this high rotation side standby area
Conversely, the air-fuel mixture may be made lean by setting TR to a value less than 1.0 depending on the type of the three-way catalyst 42, etc. Next, the process proceeds to step 427, where the water temperature increase coefficient 1 (TILI) canceled in step 425 is set to the predetermined value K TWO described above. As a result, the air-fuel mixture supplied to the engine 31 in the standby region can be made lean. , coupled with the cancellation of the correction coefficient and variable in step 425, the occurrence of afterfire and the performance deterioration of the three-way catalyst 42 due to the temperature of the three-way catalyst 42 can be prevented when the engine 31 is at a low temperature. Next, step 41 of the above step 418 can be prevented.
Then, the slip control complementary coefficient KSrs and the water temperature increase coefficient KTW set in steps 426 and 427 are applied to inject fuel 1/1, and the program ends.The answer to step 421 is 1 is set (Yes), that is, when the fuel cutoff (1 to 1) is input and the vehicle is in the fuel cutoff area, the process proceeds to step 428, and the fourth flag FLGFC4 is set to O.
Determine whether it is equal to or not. The answer to this step 428 is affirmative (Yes), that is, the fourth flag FLGrcrq is 0.
, the third flag FTG Fcr3 is set to 1 in step 429, and then step 4
At step 30, the first flag FLGFCTI is set to 1, and step 431 is further executed to perform a fuel cut (one section of (d) and (3) in FIG. 5), and this program ends. . The fourth flag FLGrcT4 is set to the value O in step 411 and step /115 described in 0]1.
As is clear from the above, this is the case when the timer r is equal to the timer value T of the TRC, and TRCIJ<O. That is, +17
゜The vehicle is in the off-standby area for a predetermined period of time, rl! If the state shifts to the fuel cut I region after c or more of ■1, the answer to step 428 is affirmative (Yes), and the fuel cut is continued. When the vehicle enters the fuel cut region, if the vehicle has remained in the off-standby region for a long time, the previous slip ratio may be excessive slip during acceleration from O or an extremely low value close to 0. Since it is expected that the fluctuation range and rate of change of the slip ratio λ will become large, by continuing the fuel cut as described above, the driving force of the engine 31 will be reliably kept at a low level of 1, and the slip ratio λ will be increased. The rate λ can be quickly converged to a desired value. Note that it is also possible to set conditions different from those described above as the condition fl for continuing the fuel cut. For example, when the throttle valve 33' changes from a fully closed state to an open state, or when the rate of change of the throttle valve opening OT11 turns -1 - around a predetermined value, the immediate drive wheels 11, +
When the slip condition in step 2 is excessive and it is determined that the slip condition is correct,
Fuconyl cutting may be continued for a certain period of time, thereby achieving the same effect as described above. When the answer to step 428 is negative (No), that is, the fourth flag F L G FCT4 is equal to 1, the process proceeds to step 432 and the first flag F L G r
Determine whether er 1 is equal to O. This first flag FLC; F(:Tl is 1);
As is clear from the knob/117 and the step knob 430, it is set to 1 when a fuel cut is executed in the fuel cut region, and is set to O in the pond region. If the answer to step 432 is affirmative (Yes), that is, the first flag FLGFcT+ is equal to O, and therefore the current loop is the loop immediately after transitioning to the fuel cut region, the process proceeds to step 433, where the F CM 2 signal is input. It is determined whether the heavy speed V of the vehicle is smaller than a second predetermined value v2. If the answer to this step 433 is affirmative (Yes), that is, the F CM 2 signal is input, and therefore V (V 2 is established), the process proceeds to step 434, and the step 42
The fourth predetermined number of times N3 is added to the second predetermined number of times N+ selected at 0.
(for example, 1) and then proceeds to step 435. In step 435, it is determined whether or not the FCM+ signal is being input, that is, whether the vehicle speed (2) of the vehicle is smaller than the first predetermined value V+. This answer is affirmative (Yes), i.e. F
CM + signal is input, so ■〈Vl
is established, the process advances to step 436, and the third predetermined number of times is selected from the first predetermined number No.
A predetermined number of times N2 (for example, 1) is subtracted, and the process then proceeds to step 437. The answer to step 435 is negative (No), that is, FCM+
When the signal is not operated manually and V2V5 holds true, and the answer to Step 433 of 01J is negative (
No), that is, the F CM 2 belief has not been manually performed, and therefore, if V2V5 is established, the process proceeds to step 437. In other words, V Only corrections are made respectively,
When V2V5 holds true, hli for both predetermined times
The market will not be held. In step 437 of 111j, the first control variable CUr
Set the first predetermined number of times No. selected in step lii+ in step 120 and supplemented with 1F in step 436 in step 43:i::j to cr+, and then in step 43
Proceed to step 8. 1) (The answer to step 432 of item j is 1 and 1Z (No), that is, the first flag F L Grcll is equal to 1. Therefore, this loop is the second and subsequent loop after moving to the fuel cut area. Sometimes, the process proceeds directly to step 438, i.e., ``double steps 432-4''.
Route 37 is executed only once immediately after transition to the fuel cut area. In the step 438, the first control variable F:1Ip
1' determines whether cr+ is equal to O or not. If the answer is negative (No), that is, CUFCTI is not O, the process proceeds to step 439, where the second control variable CUFCT2 is set to
n; Set the second predetermined number of times N1 selected in step 420 or corrected in step 434. Then, in step 440, the value 1 is subtracted from the first control variable Cure month, and further in step 430
Then, step 431 is executed to perform a fuel cut (section E+ of (cl) (3) in FIG. 5), and this program is ended. If the answer to step 438 is affirmative (Yes), that is, the first control variable CUFCTI is equal to O, the process proceeds to step 441, where it is determined whether the second control variable CUFCTI is equal to O or not. If the answer to step 441 is negative (No), that is, CUpcr2 is not O, the process proceeds to step 442, where the value 1 is subtracted from this second control variable CUFCT2. Next, the process advances to step 443 and 01j
As in step 425, all complementary i1E coefficients and correction variables are canceled. Next, the complement for nullip control i [
: As the coefficient KSn+, ]) The predetermined value for the fuel cut region selected in step 420 of 1j.
In step 445, the water temperature increase 11r coefficient KTII+ is set to 1.
Set to 0. Further, step 8 of step 01j is executed, and these correction coefficients and correction variables are applied to the equation (3) to perform fuel injection, and this program ends. If step 441 of step 441 is constant (Yes), that is, the second control variable CU rcr2 is equal to O, the process proceeds to step 446, and 1) step 43 of step ii is similarly set to the first control variable CUFCTI. 1 predetermined number of times N
Set O, then execute steps 440, 430 and 431, cut the fuel, and end this program. As described above, even when the vehicle is in the fuel cut region, when the fourth flag FLGpcTq is equal to 1, the fuel cut is not continued, but the number of times T''DC is equal to the first predetermined number No. Execution of the fuel cut and cancellation of the fuel cut for a number of TDCN equal to the second predetermined number of times N1 are alternately repeated (section L of (cl) (3) in FIG. 5).Fourth flag FLG
As is clear from step 411 and old 3, FCT4 is set to 1 when the time the vehicle remains in the off-standby area before transitioning to the fuel cut area is less than the predetermined time tTpe, or when 429.
As is clear from 422, 424, etc., this is a case where the vehicle transitions from the fuel cut area to the standby area and returns to the fuel cut area again without transitioning to the off standby area. In other words, this is a case where slip control is performed at relatively short time intervals, and in such a case, the variation range and rate of change of the slip ratio λ are small, so it is difficult to execute and release the fuel cut as described above. By performing each with a predetermined number of I' I) C,
It is possible to prevent driving shock caused by a sudden decrease in the driving l/lux of the engine 31, and to improve drivability. Also, in this case, when the fuel cut is released, the engine 3
The air-fuel ratio of the air-fuel mixture supplied to step 1 is 0;
At 20, the engine speed Ne is 1.1. : In the standby 11'l region, the predetermined value X5TR for the standby region, which is set as the slip control complementary coefficient Ks [■ 11η rotation number N
Similarly to the setting according to e, it is possible to prevent the temperature of the two-way catalyst 42 and the occurrence of afterfire over the entire range of the engine speed Ne, and also to improve driveability. can. Furthermore, as described above, the first predetermined number of times No. and the second predetermined number of times N1 that determine the GoI]C number ratio for executing and canceling the fuel cut are basically the same as the engine rotation speed N (+). Since it is set as follows, the predetermined 4i' (X T e<
It is possible to obtain the same effect as in the case described above in which : is set according to the engine speed Ne. In this embodiment, the first and second predetermined times NO and N1 are set according to the engine rotation speed Ne, but the invention is not limited to this, and the detected slip state of the vehicle, for example, the slip rate λ or the amount of change in slip rate may be set depending on the person. That is, the larger the slip ratio or the amount of change in slip ratio λ, the more it is necessary to reduce the driving torque of the engine 31.
Alternatively, by setting the first predetermined number of times NO or the second predetermined number of times N1 according to the amount of change in slip ratio, the air-fuel ratio of the air-fuel mixture is controlled to an appropriate value by directly reflecting the slip state of the vehicle. I can do it. Therefore, by being able to appropriately avoid reducing the driving force (of the engine 31),
The slip ratio λ or the slip ratio change amount λ can be quickly converged to a desired value. Furthermore, a predetermined value X for the standby region, STB, a predetermined value Xrgc for the fuel cut region, and a first predetermined number of times No.
Alternatively, instead of setting the second predetermined number of times N1 according to the engine speed Ne, or in addition to this, it may be set according to the engine load, for example, the intake pipe absolute pressure 1)RΔ or the throttle valve opening 0T11. That is, the amount of decrease in the driving force of the engine 31 due to slip control is
Since the air-fuel ratio of the mixture varies depending on the size of the load, if the air-fuel ratio of the air-fuel mixture is set to suit high-load operating conditions, it will be over-controlled in low-load operating states, but it will be set to suit low-load operating states. If this happens, there will be insufficient control in high-load operating conditions. Therefore, the predetermined value X5T
By setting the predetermined number of times No. or N1 of R, XTlIC1 according to the engine load, air-fuel ratio control for slip control can be appropriately performed over the entire load range of the engine 31, and good drivability can be ensured. can. In this case, engine speed Ne and intake pipe absolute pressure 1"
When setting the predetermined value X5TI+, etc. in 11j by both R and R, set the predetermined value X5TR, etc. to the engine rotation speed Ne.
It is of course possible to create a map based on the intake pipe absolute pressure []B^, and the period for executing and canceling the fuel cut can be set in various ways.
The predetermined number of times No. and the second predetermined number N1 of 1 on the driven wheel side
It may be set according to the f-wheel speed. In addition, the ratio of the execution and cancellation periods of the fuel cut is determined by T D as described above.
Instead of using the C number ratio, it is also possible to use a time ratio depending on the operating state of the engine 31, or to use a fixed value when simplifying the control device. (Effects of the Invention) As described in detail below in 11, the present invention provides a driving wheel slip control device in which the engine output reducing means reduces the amount of fuel from the fuel and old co-supply means for a first predetermined period when an excessive slip condition is detected. :
a fuel supply stop f stage in which the fuel supply is stopped at step F1, and a fuel t1 reduction in which the fuel supplied from the fuel supply means is reduced during a second predetermined period after the end of the fuel supply stop when the excessive slip state is detected. Therefore, when the driving wheels shift to an excessive slip state, the driving shock caused by the sudden decrease in the engine driving torque is avoided and the driving f'l is reduced.
: Can be increased. In addition, by setting the ratio between the first predetermined time and the second predetermined time and/or the low M value of kl fuel t1 according to the engine speed, the engine speed can be maintained over the entire range of the engine speed. It stabilizes the combustion characteristics and reliably reduces the amount of unburned fuel, reducing the occurrence of afterfire and the temperature of the three-way catalyst in the exhaust system.
It is possible to prevent performance deterioration of the three-way catalyst caused by 11. Furthermore, by setting the reduction value of the ratio and/or fuel)'1 according to the absolute pressure in the intake pipe, the slip ratio of the driving wheels can be quickly controlled to a desired value over the entire engine load range, so that the driving speed can be improved. You can further improve your sexual performance. In addition, the slip rate of the driving wheels and/or
Alternatively, by setting the amount of change in the slip ratio at the same time, the slip ratio of the drive wheels can be quickly controlled to a desired value by directly reflecting the slip state, so that drivability can be improved. be effective.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a vehicle equipped with a drive wheel slip control device made by Kiyoake, Fig. 2 is a block diagram of a fuel supply control device that controls the torque of the drive wheels, and Fig. 3 is a logic diagram of the peripheral part of ECLJ35. A circuit diagram, FIG. 4 is a flowchart of a control program for performing slip control, and FIG. 5 is a diagram showing the relationship between the slip rate or the amount of change in slip rate, the output signal from the logic circuit diagram in FIG. 3, and slip control. , FIG. 6 is a diagram showing a table of predetermined values and predetermined times applied to the control program of FIG. 4.5, FIG. 7 is a diagram showing a table of predetermined values KTWO of the water temperature increase coefficient KTILI, and FIG. FIG. 3 is a characteristic diagram of the frictional force between a tire and a road surface with respect to a slip rate.・Vehicle, 11.12...1μ driving wheel, 2j, 22...
Drive wheel speed sensor, 23.24...driven wheel speed sensor,
31...Engine, 35...Electronic control unit I-(ECU), 36...Fuel injection valve, 38...Intake pipe absolute pressure sensor, 40...Engine rotation speed sensor.

Claims (1)

[Claims] 1. A fuel supply means for supplying fuel to the engine according to the operating state of the engine, an excessive slip detection means for detecting an excessive slip state of the drive wheels of the vehicle, and the excessive slip detection means In the driving wheel slip control device, the driving wheel slip control device includes an engine output reduction means that reduces the output of the engine when an excessive slip condition is detected, wherein the engine output reduction means is configured to perform a first predetermined period of time when the excessive slip condition is detected.
a fuel supply stop means for stopping fuel supply from the fuel supply means; and a fuel supply stop means for reducing the amount of fuel supplied from the fuel supply means for a second predetermined period after the end of the stop of the fuel supply when the excessive slip state is detected. A drive wheel slip control device comprising: weight reduction means. 2. The driving wheel slip control device according to claim 1, wherein the ratio between the first predetermined period and the second predetermined period depends on the operating state of the engine. 3. The driving wheel slip control device according to claim 2, wherein the parameter representing the operating state of the engine is at least one of engine speed and intake pipe absolute pressure. 4. The drive wheel slip control device according to claim 1, wherein the ratio between the first predetermined period and the second predetermined period depends on a slip state of the drive wheel. 5. The driving wheel slip control device according to claim 4, wherein the parameter representing the slip state of the driving wheel is at least one of a slip ratio and a slip ratio change amount. 6. The driving wheel slip control device according to claim 1, wherein the fuel reduction value by the fuel reduction means depends on the operating state of the engine. 7. The driving wheel slip control device according to claim 6, wherein the parameter representing the operating state of the engine is at least one of engine speed and intake pipe absolute pressure.