JP4193534B2 - Differential limit control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of a differential limiting control device applied to a vehicle equipped with an anti-lock brake system (hereinafter abbreviated as “ABS”) and a differential limiting system.
[0002]
[Prior art]
Conventionally, a differential limiting control device applied to a vehicle equipped with an ABS and a differential limiting system reduces the clutch engagement force to zero when it is determined that the ABS has started operating while driving in a four-wheel drive state. That is, control is performed such that the two-wheel drive state is achieved by completely releasing the clutch, the state is maintained while the ABS is in operation, and the clutch is engaged when it is determined that the operation of the ABS has ended (see, for example, Patent Document 1). ).
[0003]
[Patent Document 1]
Japanese Patent No. 2600717 (Step 103 and Step 104 in FIG. 4).
[0004]
[Problems to be solved by the invention]
In ABS, when the wheel speed of a certain wheel is greatly reduced with respect to the vehicle body speed due to a change in running resistance in an uneven road surface state or sandy ground (for example, “1 wheel grip, The wheel speed may fall below the ABS control start threshold value, and therefore ABS control may intervene even when the brake pedal is not depressed. .
[0005]
In this case, the conventional differential limiting control device proceeds to step 104 when it is determined that the ABS is operating in step 103 in FIG. 4, and in step 104, the clutch engagement force is set to zero. Therefore, there is a problem that the two-wheel drive state may occur and the running performance and the acceleration performance may not be ensured even though the original four-wheel drive state is desired to be continued.
[0006]
The present invention has been made paying attention to the above problems, and the antilock brake system malfunctioned due to disturbance such as a change in running resistance while preventing control interference between the antilock brake control and the differential limit control . when if the driver is determined to be the driving force request, and aims to provide a differential limiting control apparatus capable of ensuring the original traveling performance and acceleration due to the differential limiting control continued To do.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention,
An anti-lock brake system that monitors the brake lock status of each wheel by comparing the vehicle speed and the wheel speed, and controls the brake fluid pressure to each wheel based on the determination that the brake lock tendency is present;
A differential limiting system that calculates a differential limiting amount that is equal to or greater than a predetermined initial differential limiting amount, and controls a differential limiting means that limits the differential between the front and rear wheels, the left and right wheels, or the left and right front and rear wheels based on the differential limiting amount ; ,
In vehicles equipped with
Anti-lock brake operation determining means for determining whether the anti-lock brake system is operating;
Driving force request determining means for determining a driving force request by a driver;
During anti-lock brake inoperative, the differential command to obtain the differential limiting amount calculated by the restriction system outputs to the differential limiting means, during the anti-lock braking, zero difference when the driver driving force request is not while for outputting a command to obtain a dynamic limit amount to the differential limiting means, at the time of driving force demand and the differential limiting control means for outputting a command to obtain the differential limiting amount calculated by the differential limiting system to the differential limiting means ,
Have
[0008]
【The invention's effect】
Therefore, in the differential limiting control device of the present invention, when the anti-lock brake is in operation and the driving force is requested, the differential limiting control means obtains the differential limiting amount calculated by the differential limiting system. since command is output to the differential limiting means, an anti-lock while achieving prevention control interference between the brake control and the differential limiting control, the disturbance such as changes in the running resistance antilock brake system malfunction the case, When it is determined that the driver is requesting the driving force, it is possible to secure the original running performance and acceleration performance by continuing the differential limiting control.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for realizing a differential limiting control device of the present invention will be described based on a first example and a second example shown in the drawings.
[0010]
(First embodiment)
First, the configuration will be described.
FIG. 1 is an overall system diagram showing a rear wheel drive-based four-wheel drive vehicle to which the differential limiting control device of the first embodiment is applied.
In FIG. 1, 1 is an engine, 2 is an automatic transmission, 3 is a rear propeller shaft, 4 is a rear differential, 5 and 6 are rear drive shafts, 7 is a left rear wheel, 8 is a right rear wheel, and 9 is a truss clutch. (Differential limiting means for front and rear wheels) 10 is a front propeller shaft, 11 is a front differential, 12 and 13 are front drive shafts, 14 is a front left wheel, and 15 is a front right wheel, and these constitute a drive system.
[0011]
The engine 1 is subjected to fuel injection control or the like according to a command from the engine controller 16, and the automatic transmission 2 is subjected to gear shift control or the like according to a command from the automatic transmission controller 17.
[0012]
The front / rear differential limiting system that controls the engagement of the transfer clutch 9 includes a front / rear differential limiting actuator 19 and a differential limiting controller 20 that outputs a fastening command or a release command to the front / rear differential limiting actuator 19. Configured.
[0013]
As the transfer clutch 9, for example, an electromagnetic multi-plate clutch, a hydraulic multi-plate clutch, or the like is applied, and it has a front-rear differential limiting function that limits the differential between the left and right rear wheels 7 and 8 and the left and right front wheels 14 and 15 by fastening. At the same time, the engine driving torque is transmitted from the left and right rear wheels 7 and 8 to the left and right front wheels 14 and 15 through the transfer clutch 9 by fastening at the time of driving, and the driving torque is distributed to the four wheels.
[0014]
Information from an accelerator opening sensor 21 (accelerator opening detecting means), a longitudinal acceleration sensor 22, a mode changeover switch 23, and the like is input to the differential limiting controller 20. The mode changeover switch 23 is means for manually switching between the 2WD fixed mode, the 4WD fixed mode, and the auto mode. When the 4WD fixed mode of the mode switch 23 is selected during traveling, four-wheel drive traveling is ensured with the front and rear wheel drive torque distribution ratio being substantially equally distributed regardless of the traveling conditions. Further, when the auto mode of the mode changeover switch 23 is selected during traveling, the driving torque distribution ratio of the front and rear wheels is variably controlled according to, for example, the front and rear wheel rotational speed difference, the accelerator opening, the front and rear acceleration, and the like.
[0015]
In FIG. 1, 30 is a brake pedal, 31 is a booster, 32 is a master cylinder, 33 and 34 are master cylinder hydraulic pipes, 35 is an ABS actuator, 36 is a left rear wheel cylinder hydraulic pipe, and 37 is a right rear wheel. Cylinder hydraulic pipe, 38 is a front left wheel cylinder hydraulic pipe, 39 is a front right wheel cylinder hydraulic pipe, 40 is a rear left wheel cylinder, 41 is a rear right wheel cylinder, 42 is a front left wheel cylinder, and 43 is The right front wheel wheel cylinder 44 is a brake controller, which constitutes an anti-lock brake system that brakes the wheels 7, 8, 14, and 15 with brake hydraulic pressure.
[0016]
The ABS actuator 35 is composed of an oil pump, a solenoid valve, and the like. During normal braking, the ABS actuator 35 is connected to each of the wheels 7, 8, via two brake hydraulic systems divided corresponding to the master cylinder hydraulic pipes 33, 34. Brake fluid pressure is supplied to 14 and 15. At the time of ABS operation, the brake fluid pressure is controlled by three modes of pressure reduction, holding, and pressure increase so as to suppress braking lock of each wheel 7, 8, 14, and 15.
[0017]
Information from a brake switch 45 (brake operation detecting means), a left front wheel speed sensor 46, a right front wheel speed sensor 47, a left rear wheel speed sensor 48, a right rear wheel speed sensor 49, and the like is input to the brake controller 44. .
[0018]
Then, the braking lock status of each wheel is monitored by comparing the estimated vehicle body speed and the wheel speed. When the wheel speed of at least one wheel falls below the ABS control start threshold, an ABS operation flag is set, The ABS operation flag is kept on until the wheel speed exceeds the ABS control end threshold.
[0019]
The engine controller 16, the automatic transmission controller 17, the differential limiting controller 20, and the brake controller 44 are connected to each other by a bidirectional communication line 50 that exchanges information.
[0020]
Next, the operation will be described.
[0021]
[ABS operation compatible differential restriction control processing]
FIG. 2 is a flowchart showing the flow of the ABS operation compatible differential restriction control process executed by the differential restriction controller 20 of the first embodiment. Each step will be described below (differential restriction control means).
[0022]
In step S1, the accelerator opening is detected based on the sensor signal from the accelerator opening sensor 21, and the process proceeds to step S2.
[0023]
In step S2, it is determined whether or not the accelerator opening detected in step S1 exceeds zero. If YES, the process proceeds to step S3. If NO, the process proceeds to step S4.
[0024]
In step S3, “driving force request determination flag” = 1 is set based on the determination that the accelerator opening degree> 0 in step S2, and the process proceeds to step S5.
[0025]
In step S4, the “driving force request determination flag” is set to 0 based on the determination that the accelerator opening is 0 in step S2, and the process proceeds to step S5. Steps S1 to S4 correspond to driving force request determination means.
[0026]
In step S5, an ABS operation flag is received from the brake controller 44, and the process proceeds to step S6.
[0027]
In Step S6, it is determined whether or not the received ABS operation flag is ABS operation flag = 1. If YES (ABS is operating), the process proceeds to Step S7. If NO (ABS is not operating), Step S9 is performed. Migrate to Steps S5 and S6 correspond to anti-lock brake operation determining means.
[0028]
In step S7, it is determined whether or not the “driving force request determination flag” is 0. If YES (no driving force requested), the process proceeds to step S8. If NO (driving force requested), the process proceeds to step S9. To do.
[0029]
In step S8, the fastening torque ΔT, which is the front / rear differential limiting amount, is set to ΔT = 0, and the process proceeds to return.
[0030]
In step S9, a command for obtaining the fastening torque ΔT calculated as the front-rear differential limit amount is output to the front-rear differential limit actuator 19, and the process proceeds to return.
For example, when the 4WD fixed mode is selected, a command for obtaining the fastening torque ΔT or the maximum fastening torque ΔTmax calculated according to the drive source torque is output. When the auto mode is selected, a command for obtaining the fastening torque ΔT calculated based on the accelerator opening Acc, the front and rear wheel rotational speed difference ΔN, and the like is output.
[0031]
[When ABS is not operating]
When the ABS is not operating, in the flowchart of FIG. 2, the flow proceeds from step S 1 → step S 2 → step S 3 (or step S 4) → step S 5 → step S 6 → step S 9. In step S 9, a command for obtaining the fastening torque ΔT calculated as the front / rear differential limiting amount is output to the front / rear differential limiting actuator 19.
[0032]
Therefore, when the 4WD fixed mode is selected, a command for obtaining a fastening torque ΔT in which the transfer clutch 9 does not slip due to the transmission torque is output to the front / rear differential limiting actuator 19, and the drive torque distribution for the four wheels is almost equally distributed. A rigid four-wheel drive state is realized, and off-road running performance on rough roads, sandy grounds, etc. is secured.
[0033]
When the auto mode is selected, for example, as shown in FIG. 3, a command for obtaining a fastening torque ΔT calculated so as to increase as the accelerator opening Acc increases is output to the front-rear differential limiting actuator 19. In other words, in response to an accelerator depression operation at the time of starting or intermediate acceleration, the drive torque distribution shifts in the four-wheel equal distribution direction, and high acceleration performance with suppressed drive slip is ensured.
[0034]
[Normal ABS operation]
At the time of low μ road braking, sudden braking operation, etc., and during normal ABS operation that suppresses braking lock, in the flowchart of FIG. 2, step S1, step S2, step S4, step S5, step S6, step S7, The flow proceeds to step S8. In step S7, it is determined that “driving force request determination flag” = 0 because it is a brake operation when the accelerator is released, and in step S8, a command for obtaining the engagement torque ΔT = 0. Is output to the front-rear differential limiting actuator 19.
[0035]
First, when the engagement of the transfer clutch 9 is maintained during the ABS operation, for example, when one of the four braking wheels is locked, all four wheels are locked by the action of limiting the differential between the front and rear wheels. The braking wheel will be locked.
[0036]
On the other hand, when the ABS operation flag is set at the time of low μ road braking or sudden braking operation, the transfer clutch 9 is engaged and released, the front and rear wheel differential is allowed, and the left and right rear wheels 7 , 8 and the left and right front wheels 14, 15 are blocked from transmitting braking torque. For this reason, when the front-rear differential restriction control and the ABS operation control compete, the ABS operation control is prioritized and the front-rear differential restriction control is temporarily stopped (transfer clutch 9 is released), thereby reducing the pressure, holding, and increasing. It is possible to ensure normal ABS operation that suppresses braking lock independently for each wheel that controls the brake fluid pressure by three pressure modes.
[0037]
[At the time of ABS malfunction]
When the vehicle is traveling on an uneven road surface, sandy land, or the like, and when the ABS malfunctions due to a change in travel resistance, in the flowchart of FIG. 2, step S1, step S2, step S3, step S5, step S6, step S7, step S9. Although the ABS operation flag is set in step S6, the process proceeds from step S7 to step S9 according to the driving force request ("driving force request determination flag" = 1) by the accelerator depression operation. In step S 9, a command for obtaining the fastening torque ΔT calculated as the front / rear differential limiting amount is output to the front / rear differential limiting actuator 19.
[0038]
Here, “ABS malfunction due to change in running resistance” will be described. For example, as shown in FIG. 4, when traveling on an uneven road, the wheel speed decreases at the concave bottom portion and the convex top portion, and increases at the inclined portion connecting the concave bottom portion and the convex top portion. It shows the characteristics of repeating low wheel speed and high wheel speed. In other words, while the vehicle speed Vcar is decelerated or constant at a constant gradient, the wheel speed is lower than the ABS operation start threshold in the region where the wheel speed is low, so the brake pedal is not depressed. Regardless, an ABS activation flag may be set and ABS control may intervene.
[0039]
Therefore, when the ABS is malfunctioning due to a change in running resistance even when traveling on uneven road surface conditions or sandy ground, the transfer clutch 9 is applied with the engagement torque calculated as the front / rear differential limiting amount, similar to when the ABS is not activated. The four-wheel drive state is maintained while being fastened by ΔT.
[0040]
For example, when traveling on rough roads or sandy grounds where the 4WD fixed mode is selected, the rigid 4 whose drive torque distribution for the four wheels is almost equal even though the ABS operation flag is set due to the ABS malfunction. The wheel drive state is maintained as it is, and off-road running performance is ensured on uneven roads and sandy ground.
[0041]
[Front / back differential limiting effect when running on sand]
FIG. 5 is a time chart showing the front-rear differential limiting action during sandy travel. Hereinafter, the front-rear differential limiting action will be described with reference to FIG.
[0042]
First, when the 4WD fixed mode is selected and travel is started by depressing the accelerator at the time point t0, the clutch engagement force suddenly increases to the maximum level from the time point t0, and a rigid four-wheel drive state is set. For this reason, the driving torque transmitted to each wheel becomes excessive, the wheel speed increases with respect to the vehicle body speed from the time point t0 to the time point t1, and a four-wheel wheel spin state is reached at the time point t1.
[0043]
In this “4-wheel wheel spin state”, the transition from the time point t1 to the time point t2 is reached. At the time point t2, the wheel speed of one of the four wheels is greatly reduced with respect to the estimated vehicle body speed due to the change in running resistance. When the “one-wheel grip, three-wheel wheel spin state” is reached, the wheel speed of the grip wheel falls below the ABS control start threshold value, and the ABS operation flag is set.
[0044]
Then, the ABS operation flag remains set from time t2 to time t3 when the wheel speed of the grip wheel exceeds the ABS control end threshold value.
[0045]
Therefore, although the brake pedal is not depressed, ABS control intervenes, and in the prior art, the clutch is released as shown by the dotted line characteristics based on the determination that the ABS is operating.
[0046]
In contrast, in the present invention, since the accelerator pedal is kept depressed from the time t2 when the ABS operation flag is set to the time t3, the “driving force request determination flag” = 1 is set. In the flowchart of FIG. 2, the flow proceeds to step S1, step S2, step S3, step S5, step S6, step S7, and step S9, and the rigid four-wheel drive state by clutch engagement is maintained, and at time t3 As is clear from the subsequent estimated vehicle body speed characteristics increasing in the acceleration direction, the ability to run on sand is ensured.
[0047]
Next, the effect will be described.
In the differential limiting control device of the first embodiment, the effects listed below can be obtained.
[0048]
(1) The braking lock state of each wheel 7, 8, 14, 15 is monitored by comparing the vehicle speed and the wheel speed, and each wheel 7, 8, 14, 15 is determined based on the judgment that the brake locking tendency is present. It is determined whether or not the ABS is operating in a vehicle equipped with an ABS that controls the brake hydraulic pressure to the vehicle and a front / rear differential limiting system that controls the transfer clutch 9 that limits the differential between the front and rear wheels. ABS operation determination steps S5 and S6, driving force request determination steps S1 to S4 for determining a driving force request by the driver, and the difference calculated by the front-rear differential limiting system during the ABS operation and when the driving force is requested. Differential limiting control means for outputting a command to obtain the dynamic limit amount ΔT to the transfer clutch 9, so that the driver can drive even if the ABS malfunctions due to disturbance such as a change in running resistance When it is determined that the request can be ensured original traveling performance and acceleration due to the differential limiting control continues.
[0049]
(2) The differential limiting control means outputs a command for obtaining a zero differential limiting amount to the transfer clutch 9 when the ABS is operating and there is no driving force request. It is possible to achieve both the prevention of control interference and the securing of running performance and acceleration when ABS malfunctions.
[0050]
(3) In the ABS operation determination steps S5 and S6, the ABS operation flag that is set based on the determination that the ABS is in a braking lock tendency is received by the front-rear differential limiting system, and the ABS operation determination is performed based on the flag determination. Therefore, it is not necessary to make an ABS operation determination by the differential limit controller 20, and it is possible to easily determine that the ABS is operating with good response.
[0051]
(4) The accelerator opening sensor 21 for detecting the accelerator opening is provided, and the driving force request determination steps S1 to S4 determine that the driving force is requested when the accelerator opening exceeds zero. Compared to determination of driving force request based on longitudinal acceleration, engine speed, engine torque, etc., the driving force request of the driver can be determined most reliably and most easily.
[0052]
(Second embodiment)
The second embodiment is an example applied to a four-wheel drive vehicle with a front wheel drive base, and is an example in which a brake non-operation is added to the drive force request determination.
[0053]
That is, as shown in FIG. 6, the left and right front wheels 14 and 15 are normally driven wheels that are directly driven by the engine 1, and the left and right rear wheels 7 and 8 are clutch-engaged drive wheels that are driven by fastening of the truss clutch 9. Only the structural difference. Other configurations are the same as those of the first embodiment shown in FIG.
[0054]
Next, the operation will be described.
[0055]
[ABS operation compatible differential restriction control processing]
FIG. 7 is a flowchart showing the flow of the ABS operation compatible differential restriction control process executed by the differential restriction controller 20 of the second embodiment. Each step will be described below (differential restriction control means).
[0056]
In step S1 ′, the accelerator opening is read based on the sensor signal from the accelerator opening sensor 21, and the switch signal from the brake switch 45 is read, and the process proceeds to step S2.
[0057]
In step S2, it is determined whether or not the accelerator opening read in step S1 ′ exceeds zero. If YES, the process proceeds to step S10, and if NO, the process proceeds to step S4.
[0058]
In step S10, it is determined whether or not the brake is not operated based on the brake signal read in step S1 ′. If YES, the process proceeds to step S3. If NO, the process proceeds to step S4.
[0059]
In step S3, based on the determination that the accelerator opening degree> 0 in step S2 and the brake is not operated in step S10, “driving force request determination flag” = 1 is set, and the process proceeds to step S5.
[0060]
In step S4, based on the determination that the accelerator opening is 0 in step S2 or the brake operation is in step S10, "driving force request determination flag" is set to 0, and step S5 Migrate to Steps S1 ′, S2, S10, S3, and S4 correspond to the driving force request determination unit of the second embodiment. Steps S5 to S9 in FIG. 7 are the same as steps S5 to S9 in FIG.
[0061]
[Driving force request judgment]
In the case of the second embodiment, the accelerator opening degree> 0 and the “driving force request determination flag” = 1 is set based on the determination that the brake is not operated, and the accelerator opening degree = 0. Based on this determination or when it is determined that the brake is being operated, “driving force request determination flag” = 0.
[0062]
That is, when the ABS malfunctions, the ABS operation flag is set even though the brake pedal is not depressed as described above, so that the brake operation condition is added to the accelerator operation condition as a driving force request determination condition. It is possible to determine the driving force request at the time of ABS malfunction more accurately. Since other operations are the same as those in the first embodiment, description thereof is omitted.
[0063]
Next, the effect will be described.
In the differential limiting control device of the second embodiment, the following effects can be obtained in addition to the effects (1), (2), and (3) of the first embodiment.
[0064]
(5) The accelerator opening sensor 21 for detecting the accelerator opening and the brake switch 45 for detecting the brake operation are provided, and the driving force request determination steps S1 ′, S2, S10, S3, and S4 have the accelerator opening. Since it is determined that the driving force is requested when it exceeds zero and the brake is not operated, it is possible to determine the driving force request at the time of ABS malfunction more accurately than in the first embodiment. .
[0065]
The differential limiting control device of the present invention has been described based on the first embodiment and the second embodiment. However, the specific configuration is not limited to these embodiments, and the scope of the claims is as follows. Design changes and additions are allowed without departing from the spirit of the invention according to each claim.
[0066]
For example, in the first embodiment and the second embodiment, an example of application to a four-wheel drive vehicle that employs a transfer clutch that is a front-rear differential limiting means has been shown, but between left and right front wheels and left and right rear wheels that are drive wheels. The present invention can be applied to a vehicle that employs a differential limiting clutch that is a left / right differential limiting means, and front / rear / left / right differential limiting means having both a transfer clutch and a differential limiting clutch are employed. The present invention can also be applied to a wheel drive vehicle.
[0067]
In the first embodiment and the second embodiment, the example of the driving force request determining means using the “accelerator opening” as the driving force request determining means is shown. However, as described below, A “longitudinal acceleration sensor value” or the like may be used.
[0068]
(1) In the case of the calculated body acceleration, the engine torque is estimated from the engine speed, accelerator opening, and engine torque map, the gear ratio information from the transmission controller is received, and the input / output speed and torque of the torque converter are received. The torque converter amplification factor is estimated from the converter map, and the vehicle body acceleration is calculated using these estimated values. If the vehicle body acceleration calculated value is equal to or greater than a set value (for example, 0.05 G), the driving force is requested. Judge.
[0069]
(2) In the case of the longitudinal acceleration sensor value, when the longitudinal acceleration sensor value calculated from the sensor signal from the longitudinal acceleration sensor 22 is a set value (for example, 0.05 G) or more, it is determined that the driving force is requested.
[Brief description of the drawings]
FIG. 1 is an overall system diagram showing a differential limiting control device according to a first embodiment;
FIG. 2 is a flowchart showing the flow of an ABS operation compatible differential restriction control process executed by the differential restriction controller of the first embodiment;
FIG. 3 is a diagram showing an example of a clutch engagement torque map with respect to an accelerator opening degree in the first embodiment device.
FIG. 4 is an explanatory diagram of a mechanism that causes an ABS malfunction when traveling on an uneven road.
FIG. 5 is a time chart showing a differential limiting control action when an ABS malfunction occurs during sandy traveling.
FIG. 6 is an overall system diagram showing a differential limiting control device of a second embodiment.
FIG. 7 is a flowchart showing a flow of an ABS operation compatible differential limit control process executed by the differential limit controller of the second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Engine 2 Automatic transmission 3 Rear propeller shaft 4 Rear differential 5, 6 Rear drive shaft 7 Left rear wheel 8 Right rear wheel 9 Truss clutch (Differential limiting means for front and rear wheels)
DESCRIPTION OF SYMBOLS 10 Front propeller shaft 11 Front differential 12, 13 Front drive shaft 14 Left front wheel 15 Right front wheel 16 Engine controller 17 Automatic transmission controller 19 Front / rear differential limiting actuator 20 Differential limiting controller 21 Accelerator opening sensor (accelerator opening detecting means)
22 Longitudinal acceleration sensor 23 Mode selector switch 30 Brake pedal 31 Booster 32 Master cylinder 33, 34 Master cylinder hydraulic pipe 35 ABS actuator 36 Left rear wheel wheel cylinder hydraulic pipe 37 Right rear wheel wheel cylinder hydraulic pipe 38 Left front wheel wheel cylinder Hydraulic pipe 39 Right front wheel wheel cylinder Hydraulic pipe 40 Left rear wheel wheel cylinder 41 Right rear wheel wheel cylinder 42 Left front wheel wheel cylinder 43 Right front wheel wheel cylinder 44 Brake controller 45 Brake switch (brake operation detection means)

Claims (4)

An anti-lock brake system that monitors the brake lock status of each wheel by comparing the vehicle speed and the wheel speed, and controls the brake fluid pressure to each wheel based on the determination that the brake lock tendency is present;
A differential limiting system that calculates a differential limiting amount that is equal to or greater than a predetermined initial differential limiting amount, and controls a differential limiting means that limits the differential between the front and rear wheels, the left and right wheels, or the left and right front and rear wheels based on the differential limiting amount ; ,
In vehicles equipped with
Anti-lock brake operation determining means for determining whether the anti-lock brake system is operating;
Driving force request determining means for determining a driving force request by a driver;
During anti-lock brake inoperative, the differential command to obtain the differential limiting amount calculated by the restriction system outputs to the differential limiting means, during the anti-lock braking, zero difference when the driver driving force request is not while for outputting a command to obtain a dynamic limit amount to the differential limiting means, at the time of driving force demand and the differential limiting control means for outputting a command to obtain the differential limiting amount calculated by the differential limiting system to the differential limiting means ,
A differential limiting control device comprising: In the differential limiting control device according to claim 1 ,
The anti-lock brake operation determining means receives an anti-lock brake operation flag that is set based on a determination that the anti-lock brake system side has a braking lock tendency, in the differential limiting system, and determines the anti-lock brake operation based on the flag determination. A differential limiting control device characterized by performing an operation determination. In the differential limiting control device according to claim 1 or 2 ,
Accelerator opening detection means for detecting the accelerator opening is provided,
The driving force request determination means determines that the driving force is requested when the accelerator opening exceeds zero. In the differential limiting control device according to claim 1 or 2 ,
An accelerator opening detecting means for detecting the accelerator opening; and a brake operation detecting means for detecting a brake operation;
The differential limiting control device according to claim 1, wherein the driving force request determining means determines that the driving force is requested when the accelerator opening exceeds zero and when the brake is not operated.

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