JP2015168411A - Vehicle brake control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle brake control device which can improve the determination accuracy of a split road.SOLUTION: A vehicle brake control device comprises: determination information acquisition means (wheel deceleration acquisition means 112, lateral acceleration acquisition means 113) which acquires split road determination information; determination means (split road determination means 140) which determines that a road is the split road at which friction coefficients of a road surface on which wheels are grounded are differ from each other at a prescribed value or larger at the left and right when it is determined that at least one determination condition is satisfied on the basis of the split road determination information and a split road determination threshold; outside air temperature acquisition means 114 which acquires an outside air temperature; and threshold setting means 120 which sets the split road determination threshold so that the road becomes difficult to be determined as the split road by the determination means, compared with the case that the outside air temperature is not higher than a prescribed temperature, when the outside air temperature is higher than the prescribed temperature.

Description

  The present invention relates to a vehicle brake control device that can determine whether or not the friction coefficient of a ground contact surface of a wheel is a split road with different left and right.

  Conventionally, as a vehicle brake control device capable of determining a split road, the maximum value of wheel deceleration (negative value) is equal to or greater than a first threshold value, and the difference in wheel deceleration between the left and right wheels is a second threshold value. When it is above, what determines that it is a split road is known (refer to patent documents 1).

JP 2013-132973 A

  By the way, at normal temperature, the possibility of becoming a split road is lower than at low temperatures where the road surface freezes. However, in the prior art, since the determination condition is always constant regardless of the state of the outside air temperature, it has been desired to further improve the determination accuracy.

  Therefore, an object of the present invention is to provide a vehicle brake control device that can improve the determination accuracy of a split road.

  In order to solve the above-described problem, a vehicle brake control device according to the present invention includes a determination information acquisition unit that acquires split road determination information, and at least one determination condition based on the split road determination information and the split road determination threshold. A determination means for determining that the friction coefficient of the ground contact surface of the wheel is different from the left and right by a predetermined difference, an outside air temperature acquisition means for acquiring the outside air temperature, and the outside air temperature is higher than the predetermined temperature. Threshold value setting means for setting the split road determination threshold so that it is less likely to be determined by the determination means as being a split road than when the outside air temperature is equal to or lower than the predetermined temperature when the temperature is high. To do.

  According to this configuration, for example, it is difficult to determine that the road is a split road at a normal temperature that is higher than a low temperature such that the road surface is frozen, so that the determination accuracy of the split road can be improved.

  In the above-described configuration, the split road determination information includes a difference between left and right wheel decelerations, and the split road determination threshold includes a first threshold corresponding to the difference between the left and right wheel decelerations, The condition is that the difference between the left and right wheel decelerations is greater than the first threshold, and the threshold setting means is configured such that when the outside air temperature is higher than a predetermined temperature, the outside air temperature is equal to or lower than the predetermined temperature. The first threshold value may be set to a larger value than the case.

  According to this, it is possible to improve the split road determination accuracy using the difference between the left and right wheel decelerations.

  In the configuration described above, the split road determination information includes a maximum value among a plurality of wheel decelerations, the split road determination threshold includes a second threshold corresponding to the maximum value, and the determination condition is The maximum value is larger than the second threshold value, and the threshold value setting means is configured such that when the outside air temperature is higher than the predetermined temperature, the second threshold value is higher than when the outside air temperature is equal to or lower than the predetermined temperature. May be set to a large value.

  According to this, the determination accuracy of the split road using the wheel deceleration can be improved.

  In the above configuration, the split road determination information includes a lateral acceleration, the split road determination threshold includes a third threshold corresponding to the lateral acceleration, and the determination condition is that the lateral acceleration is the third acceleration. When the outside air temperature is higher than the predetermined temperature, the threshold value setting means sets the third threshold value to a smaller value than when the outside air temperature is equal to or lower than the predetermined temperature. It may be configured.

  According to this, it is possible to improve the split road determination accuracy using the lateral acceleration.

  According to the present invention, it is possible to improve the split road determination accuracy.

It is a lineblock diagram of vehicles provided with a brake control device for vehicles concerning an embodiment. It is a block diagram which shows the structure of a hydraulic unit. It is a block diagram which shows the structure of a control part. It is a flowchart which shows operation | movement of a control part. It is a time chart which shows an example of the determination method of a split road.

Next, embodiments will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, the vehicle brake control device A according to the present embodiment is a device that appropriately controls the braking force applied to each wheel W of the vehicle CR. The vehicle brake control device A mainly includes a hydraulic unit 10 provided with an oil passage and various parts, and a control unit 100 for appropriately controlling various parts in the hydraulic unit 10.

  Each wheel W is provided with a wheel brake FL, RR, RL, FR, and each wheel brake FL, RR, RL, FR is braked by a hydraulic pressure supplied from a master cylinder MC as a hydraulic pressure source. Is provided. Master cylinder MC and wheel cylinder H are each connected to hydraulic unit 10. In normal times, the brake hydraulic pressure generated in the master cylinder MC in response to the depression force of the brake pedal BP (driver's braking operation) is supplied to the wheel cylinder H after being controlled by the control unit 100 and the hydraulic unit 10. Is done.

  The control unit 100 includes a pressure sensor 91 for detecting the pressure of the master cylinder MC, a wheel speed sensor 92 for detecting the wheel speed of each wheel W, a temperature sensor 93 for detecting the outside air temperature, and the vehicle CR in the left-right direction. A lateral acceleration sensor 94 that detects such acceleration (hereinafter referred to as lateral acceleration) is connected. The control unit 100 includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and an input / output circuit, and inputs from the sensors 91 to 94 and the ROM The control is executed by performing various arithmetic processes based on the programs and data stored in. Details of the control unit 100 will be described later.

  As shown in FIG. 2, the hydraulic unit 10 is disposed between the master cylinder MC and the wheel brakes FL, RR, RL, FR. The two output ports M1, M2 of the master cylinder MC are connected to the inlet port 10a of the hydraulic unit 10, and the outlet port 10b is connected to each wheel brake FL, RR, RL, FR. In normal times, the oil pressure path of the brake pedal BP is transmitted to the wheel brakes FL, RR, RL, and FR because the oil passage communicates from the inlet port 10a to the outlet port 10b in the hydraulic unit 10. It has become so.

  The hydraulic pressure unit 10 is provided with four inlet valves 1, four outlet valves 2, and four check valves 1a corresponding to the wheel brakes FL, RR, RL, FR. The hydraulic unit 10 is also provided with a reservoir 3, a pump 4, and an orifice 5a in each of the hydraulic pressure paths 11 and 12 corresponding to the output ports M1 and M2 of the master cylinder MC. The hydraulic unit 10 is provided with a common motor 6 for driving the pumps 4.

  The inlet valve 1 is a normally open proportional solenoid valve provided between each wheel brake FL, RR, RL, FR and the master cylinder MC. The inlet valve 1 is normally opened to allow the brake hydraulic pressure to be transmitted from the master cylinder MC to the wheel brakes FL, RR, RL, FR. In addition, the inlet valve 1 is blocked by the control unit 100 when the wheel W is about to be locked, thereby cutting off the hydraulic pressure transmitted from the brake pedal BP to each wheel brake FL, RR, RL, FR.

  The outlet valve 2 is a normally closed electromagnetic valve provided between each wheel brake FL, RR, RL, FR and the reservoir 3. Although the outlet valve 2 is normally closed, the hydraulic pressure applied to the wheel brakes FL, RR, RL, FR is applied to the reservoir 3 by being released by the control unit 100 when the wheel W is about to be locked. Let it go.

  The check valve 1a is connected to each inlet valve 1 in parallel. This check valve 1a is a valve that only allows the brake fluid to flow from the wheel brakes FL, RR, RL, FR side to the master cylinder MC side, and the inlet valve when the input from the brake pedal BP is released. Even when 1 is closed, the flow of brake fluid from each wheel brake FL, RR, RL, FR side to the master cylinder MC side is allowed.

The reservoir 3 has a function of temporarily storing brake fluid that is released when each outlet valve 2 is opened.
The pump 4 is provided between the reservoir 3 and the master cylinder MC, and has a function of sucking the brake fluid stored in the reservoir 3 and returning the brake fluid to the master cylinder MC through the orifice 5a. ing.

  The inlet valve 1 and the outlet valve 2 control the brake fluid pressure of the wheel cylinders H of the wheel brakes FL, RR, RL, FR by the control unit 100 controlling the open / close state. For example, in a normal state where the inlet valve 1 is open and the outlet valve 2 is closed, if the brake pedal BP is depressed, the hydraulic pressure from the master cylinder MC is transmitted to the wheel cylinder H as it is, and the pressure is increased. When the valve 1 is closed and the outlet valve 2 is opened, the brake fluid flows out from the wheel cylinder H to the reservoir 3 side to be in a reduced pressure state, and when both the inlet valve 1 and the outlet valve 2 are closed, the brake fluid pressure is increased. It becomes a holding state to be held.

Next, details of the control unit 100 will be described.
The control unit 100 is a device that performs control to stabilize the vehicle by controlling the hydraulic unit 10 and applying the braking force set to each wheel brake FL, RR, RL, FR. Therefore, as shown in FIG. 3, the control unit 100 includes a vehicle speed acquisition unit 111, a wheel deceleration acquisition unit 112 and a lateral acceleration acquisition unit 113 as an example of a determination information acquisition unit, and an outside air temperature acquisition unit 114. , Threshold setting means 120, antilock brake control means 130, split road determination means 140 as determination means, differential pressure setting means 150 as an example of braking force difference setting means, control execution means 160, storage means 190 mainly.

  The vehicle speed acquisition unit 111 acquires wheel speed WS information (pulse signal of the wheel speed sensor 92) from the wheel speed sensor 92, and calculates the vehicle speed V by a known method based on the information of the wheel speed WS. It is a means to acquire. The calculated vehicle speed V is output to the antilock brake control means 130.

  The wheel deceleration acquisition unit 112 is a unit that calculates and acquires the wheel deceleration WD of each wheel W based on the information on the wheel speed WS acquired from each wheel speed sensor 92. Specifically, the wheel deceleration acquisition unit 112 calculates the wheel deceleration WD of the wheel W by subtracting the previous wheel speed WS from the current wheel speed WS. That is, when the vehicle is decelerated, the wheel deceleration WD is a negative value.

  Then, the wheel deceleration acquisition means 112 calculates the wheel deceleration WD (the wheel deceleration of the wheel with the least deceleration) that is the maximum value WDmax among the calculated plurality of wheel decelerations WD as the split road determination information. And the maximum value WDmax of the wheel deceleration WD is output to the split road determination means 140. Further, the wheel deceleration acquisition unit 112 determines the difference between the wheel deceleration WD of the left and right front wheels (hereinafter also referred to as the wheel deceleration difference ΔD) and the wheel deceleration difference ΔD of the left and right rear wheels as split road determination information. And the wheel deceleration difference ΔD is output to the split road determination means 140.

  The lateral acceleration acquisition unit 113 is a unit that acquires the lateral acceleration SA from the lateral acceleration sensor 94. The acquired lateral acceleration SA is output to the split road determination unit 140 as split road determination information.

  The outside air temperature acquisition unit 114 is a unit that acquires the outside air temperature T from the temperature sensor 93. The acquired outside air temperature T is output to the threshold setting means 120.

  The threshold setting means 120 is a means for setting a split road determination threshold used for determination by the split road determination means 140 based on the outside air temperature T output from the outside air temperature acquisition means 114. Specifically, the storage unit 190 stores a low temperature threshold value used when the outside air temperature T is equal to or lower than a predetermined temperature, and a normal temperature threshold value used when the outside air temperature T is higher than the predetermined temperature. When the outside air temperature T is equal to or lower than the predetermined temperature, 120 reads the low temperature threshold value from the storage unit 190 and outputs the low temperature threshold value to the split road determination unit 140. When the outside air temperature T is higher than the predetermined temperature, the threshold setting unit 120 reads the room temperature threshold from the storage unit 190 and outputs the room temperature threshold to the split road determination unit 140.

  Here, the predetermined temperature can be set to a temperature at which the road surface freezes, for example. The room temperature threshold is set to a value that makes it difficult for the split road determination means 140 to determine that the road is a split road than the low temperature threshold. Further, three room temperature thresholds and three low temperature thresholds are set in correspondence with three determination conditions (to be described later) in the split road determination unit 140.

  The anti-lock brake control means 130 determines, for each wheel W, whether or not to execute the anti-lock brake control by a known method based on the wheel speed WS and the vehicle speed V, and the liquid during the anti-lock brake control. This is means for determining for each wheel W an instruction for pressure control (instruction on whether the hydraulic pressure in the wheel cylinder H is to be in a pressure-increasing state, a holding state, or a pressure-reducing state). Information indicating that the anti-lock brake control is to be executed is output to the split road determination unit 140, and the determined hydraulic pressure control instruction is output to the control execution unit 160.

  The split road determination means 140 is a means for determining whether or not the split road has a friction coefficient different from the left and right by a predetermined amount or more when the antilock brake control is executed. Specifically, the split road determination unit 140 determines whether or not all three determination conditions are satisfied based on the split road determination information and the split road determination threshold, and splits when all three determination conditions are satisfied. It is determined that the road.

  Specifically, the split road determination unit 140 determines that at least one of the wheel deceleration difference ΔD of the left and right front wheels and the wheel deceleration difference ΔD of the left and right rear wheels output from the wheel deceleration acquisition unit 112 is a wheel deceleration difference. When it is larger than the corresponding first threshold value TH1, it is determined that the first determination condition is satisfied.

  Further, the split road determination unit 140 determines that the second value TH2 of the wheel deceleration WD output from the wheel deceleration acquisition unit 112 is greater than the second threshold value TH2 corresponding to the maximum value WDmax. It is determined that the determination condition is satisfied. Here, the second threshold value TH2 is set to a negative value because the wheel deceleration WD is calculated as a negative value when the vehicle is decelerated.

  In the second determination, it is determined whether or not the deceleration is occurring. When the deceleration is not greater than the predetermined wheel deceleration (that is, the second threshold TH2), the second determination condition is satisfied. It is judged to satisfy. Therefore, for example, when the wheel deceleration is calculated as a positive value, the second threshold is set as a positive value, and the minimum value of the wheel deceleration is smaller than the second threshold corresponding to the minimum value. May be set as the second determination condition.

  Further, the split road determination unit 140 determines that the third determination condition is satisfied when the lateral acceleration SA output from the lateral acceleration acquisition unit 113 is smaller than the third threshold value TH3 corresponding to the lateral acceleration SA. .

  And each threshold value TH1-TH3 is suitably set according to the outside temperature T by the threshold value setting means 120 mentioned above. Specifically, the storage unit 190 includes a low temperature first threshold value TH11 for setting as the first threshold value TH1 when the outside air temperature T is equal to or lower than a predetermined temperature, and a first value when the outside air temperature T is higher than the predetermined temperature. The first threshold value TH12 for room temperature for setting as the threshold value TH1 is stored. The normal temperature first threshold TH12 is set to a value larger than the low temperature first threshold TH11.

  The storage unit 190 also includes a low temperature second threshold TH21 for setting as the second threshold TH2 when the outside air temperature T is equal to or lower than a predetermined temperature, and a second threshold when the outside air temperature T is higher than the predetermined temperature. A second threshold value TH22 for room temperature for setting as TH2 is stored. The room temperature second threshold TH22 is set to a value larger than the low temperature second threshold TH21.

  The storage unit 190 also includes a low temperature third threshold value TH31 for setting as the third threshold value TH3 when the outside air temperature T is equal to or lower than a predetermined temperature, and a third threshold value when the outside air temperature T is higher than the predetermined temperature. A third threshold value TH32 for room temperature for setting as TH3 is stored. The room temperature third threshold TH32 is set to a value smaller than the low temperature third threshold TH31.

  When the split road determination unit 140 determines that the road is a split road, it outputs information indicating that to the differential pressure setting unit 150.

  The differential pressure setting means 150 is a means for setting a braking force difference that is a difference between the braking force of the wheel brake on the high friction coefficient side and the braking force of the wheel brake on the low friction coefficient side on the split road. In the present embodiment, a differential pressure DP that is a difference between the brake fluid pressure of the wheel brake on the high friction coefficient side and the brake fluid pressure of the wheel brake on the low friction coefficient side is set as a value corresponding to the braking force difference.

  In addition, what is necessary is just to employ | adopt a well-known method as the setting method of a differential pressure, for example, can set a differential pressure based on a vehicle speed or a steering angle.

  When the differential pressure DP is set by receiving information indicating that the road is a split road from the split path determination unit 140, the differential pressure setting unit 150 outputs the set differential pressure DP to the control execution unit 160. Further, the differential pressure setting means 150 does not set the differential pressure DP when the information indicating that the road is a split road is not received from the split road determination means 140.

  Based on the hydraulic pressure control instruction determined by the anti-lock brake control means 130 and the differential pressure DP set by the differential pressure setting means 150, the control execution means 160 uses a known method to cause the wheel brakes FL, RR, RL, It is means for controlling the brake fluid pressure of FR. Specifically, for the wheel brake that executes the antilock brake control, the hydraulic pressure unit 10 is controlled based on the hydraulic pressure control instruction determined by the antilock brake control means 130. Also, when it is determined that the road is split, if the difference between the brake fluid pressure of the wheel brake on the high friction coefficient side and the brake fluid pressure of the wheel brake on the low friction coefficient side is likely to exceed the differential pressure DP The hydraulic pressure unit 10 is controlled such that the brake fluid pressure of the wheel brake on the high friction coefficient side becomes a value obtained by adding the differential pressure DP to the brake fluid pressure of the wheel brake on the low friction coefficient side. The specific control of the hydraulic unit 10 is well known and will not be described in detail. However, in brief, the current output to the inlet valve 1 and the outlet valve 2 is adjusted, and the motor 6 is turned on as necessary. It controls to drive and drive the pump 4.

  The storage unit 190 is a unit that stores the low-temperature threshold value and the normal-temperature threshold value, as well as programs, constants, maps, calculation results, and the like necessary for the operation of the control unit 100 as appropriate.

Next, a split road determination method by the control unit 100 will be described in detail with reference to FIG.
As shown in FIG. 4, the control unit 100 first determines whether or not the outside air temperature T is higher than a predetermined temperature (S1). When the outside air temperature T is equal to or lower than the predetermined temperature in step S1 (NO), the control unit 100 sets the split road determination threshold value as a low temperature threshold value (S2). Specifically, in step S2, the control unit 100 sets the first threshold value TH1 used in the first determination condition to the first threshold value TH11 for low temperature, and sets the second threshold value TH2 used in the second determination condition to the second threshold value TH21 for low temperature. And the third threshold value TH3 used in the third determination condition is set as the low temperature third threshold value TH31.

  When the outside air temperature T is higher than the predetermined temperature in step S1 (YES), the control unit 100 sets the split road determination threshold value to the room temperature threshold value (S3). Specifically, in step S3, the control unit 100 sets the first threshold value TH1 used in the first determination condition as the first threshold value TH12 for normal temperature, and sets the second threshold value TH2 used in the second determination condition as the second threshold value TH22 for normal temperature. And the third threshold value TH3 used in the third determination condition is set to the third threshold value TH32 for room temperature.

  After step S2 or step S3, the control unit 100 determines whether or not the wheel deceleration difference ΔD between the left and right front wheels or the left and right rear wheels is greater than the first threshold value TH1 (S4). When it is determined in step S4 that the wheel deceleration difference ΔD is larger than the first threshold value TH1 (YES), the control unit 100 determines whether or not the maximum value WDmax of the wheel deceleration WD is larger than the second threshold value TH2. Is determined (S5).

  If it is determined in step S5 that the maximum value WDmax of the wheel deceleration WD is larger than the second threshold value TH2 (YES), the control unit 100 determines whether the lateral acceleration SA is smaller than the third threshold value TH3. (S6). When it is determined in step S6 that the lateral acceleration SA is smaller than the third threshold value TH3 (YES), that is, when it is determined that all three determination conditions are satisfied, the control unit 100 determines that the road is a split road. Then, the flag F indicating the split road is set to 1, and this control is finished.

  When it is determined NO in any of steps S4 to S6, that is, when it is determined that one of the three determination conditions is not satisfied, the control unit 100 determines that the road is not a split road, and flag F Is set to 0, and this control is terminated.

  Next, an example of a split road determination method when the vehicle CR travels on a road surface that is not a split road at normal temperature will be described in detail with reference to FIG.

  As shown in FIGS. 5A and 5E, when the driver depresses the brake pedal BP (time t1), the brake fluid pressure in each wheel cylinder H (for example, the brake fluid pressures PL and PR for the left and right front wheels). As the pressure increases, each wheel speed (for example, the wheel speeds WSL and WSR of the left and right front wheels) gradually decreases. When the wheel speed WSL of the left front wheel of the left and right front wheels becomes smaller than a predetermined value with respect to the vehicle speed V (time t2), antilock brake control is started for the left front wheel, and the brake in the wheel cylinder H of the left front wheel is started. The hydraulic pressure PL is reduced.

  When the anti-lock brake control is started (time t2), the control unit 100 determines whether or not the currently traveling road surface is a split road. In the example of FIG. 5, it is assumed that the maximum value WDmax of the wheel deceleration, the wheel deceleration difference ΔD between the left and right front wheels, and the lateral acceleration SA change as shown in FIGS.

  In this case, for example, when the split road determination threshold is fixed to a constant value regardless of the outside air temperature as in the past (for example, when the three thresholds TH1, TH2, TH3 are fixed to the low temperature thresholds TH11, TH21, TH31), Since all three determination conditions are satisfied at time t2, it is erroneously determined that the road is a split road. Specifically, at time t2, as shown in FIG. 5C, the first determination condition is satisfied by satisfying the wheel deceleration difference ΔD> the first threshold value TH1 (= TH11), which is shown in FIG. 5B. Thus, the second determination condition is satisfied when the maximum value WDmax of the wheel deceleration WD> the second threshold value TH2 (= TH21), and as shown in FIG. 5D, the lateral acceleration SA <the third threshold value TH3. By satisfying (TH31), the third determination condition is satisfied. When it is determined that the road is a split road in this way, as indicated by a broken line in FIG. 5E, a differential pressure is set in the control after time t2, and the brake fluid pressure Pr of the right front wheel is set to the left side. It is limited to a value obtained by adding a differential pressure to the brake fluid pressure PL of the front wheel.

  On the other hand, in the present embodiment, the control unit 100 determines that the outside air temperature T acquired from the temperature sensor 93 is higher than the predetermined temperature at the normal temperature, and therefore, shown in FIGS. As described above, the control unit 100 sets the three threshold values TH1, TH2, and TH3 to the room temperature threshold values TH12, TH22, and TH32. As a result, at time t2, it is not determined that the road is a split road (in the example of FIG. 5, all three determination conditions are not satisfied).

  Specifically, at time t2, as shown in FIG. 5C, the first determination condition is not satisfied because the wheel deceleration difference ΔD <the first threshold value TH1 (= TH12), and FIG. As shown in FIG. 5D, the maximum value WDmax of the wheel deceleration WD <the second threshold value TH2 (= TH22), so that the second determination condition is not satisfied, and the lateral acceleration SA> third as shown in FIG. The third determination condition is not satisfied when the threshold value TH3 (TH32) is reached. If it is not determined that the road is a split road in this way, as indicated by a thick solid line in FIG. 5E, in the control after time t2, the differential pressure is not set, and the brake hydraulic pressure PR of the right front wheel is set to It can be increased without being limited by the differential pressure.

According to the above, the following effects can be obtained in the present embodiment.
Since it is difficult to determine that the road is a split road at a normal temperature that is higher than a low temperature at which the road surface freezes, it is possible to improve the determination accuracy of the split road.

In addition, this invention is not limited to the said embodiment, It can utilize with various forms so that it may illustrate below.
In the above embodiment, the split road determination conditions are three. However, the present invention is not limited to this, and at least one determination condition may be provided.

  In the above-described embodiment, all the threshold values of the plurality of determination conditions are set according to the outside air temperature. However, the present invention is not limited to this, and the threshold value of at least one determination condition out of the plurality of determination conditions is excluded. You may make it set according to temperature.

  In the above embodiment, the wheel deceleration is treated as a negative value, but the present invention is not limited to this, and the wheel deceleration may be treated as a positive value. In this case, the second threshold value is set as a positive value, and the condition that the minimum value of the wheel deceleration is smaller than the second threshold value corresponding to the minimum value may be set as the second determination condition. Further, in this case, the threshold value setting means may be configured to set the second threshold value to a smaller value when the outside air temperature is higher than the predetermined temperature than when the outside air temperature is equal to or lower than the predetermined temperature. .

  In the above-described embodiment, the vehicle brake control device A using the brake fluid is illustrated, but the present invention is not limited to this. For example, an electric brake device that generates a braking force by an electric motor without using the brake fluid. It may be a vehicle brake control device for controlling.

112 Wheel deceleration acquisition means 113 Lateral acceleration acquisition means 114 Outside air temperature acquisition means 120 Threshold setting means 140 Split road determination means

Claims (4)

Determination information acquisition means for acquiring split road determination information;
Determining means for determining that the friction coefficient of the ground contact surface of the wheel is different from the left and right by a predetermined distance or more when it is determined that at least one determination condition is satisfied based on the split road determination information and the split road determination threshold; A vehicle brake control device comprising:
Outside temperature acquisition means for acquiring outside temperature;
When the outside air temperature is higher than the predetermined temperature, the threshold setting means for setting the split road determination threshold so that the determination means makes it difficult to determine that the outside air temperature is equal to or lower than the predetermined temperature. A vehicle brake control device. The split road determination information includes a difference between left and right wheel decelerations,
The split road determination threshold includes a first threshold corresponding to the difference between the left and right wheel decelerations,
The determination condition is that a difference between the left and right wheel decelerations is larger than the first threshold value.
The threshold value setting unit sets the first threshold value to a larger value when the outside air temperature is higher than a predetermined temperature than when the outside air temperature is equal to or lower than the predetermined temperature. Vehicle brake control device. The split road determination information includes a maximum value among a plurality of wheel decelerations,
The split road determination threshold includes a second threshold corresponding to the maximum value,
The determination condition is that the maximum value is larger than the second threshold value,
The threshold value setting means sets the second threshold value to a larger value when the outside air temperature is higher than a predetermined temperature than when the outside air temperature is equal to or lower than the predetermined temperature. Item 3. The vehicle brake control device according to Item 2. The split road determination information includes lateral acceleration,
The split road determination threshold includes a third threshold corresponding to the lateral acceleration,
The determination condition is that the lateral acceleration is smaller than the third threshold value,
The threshold value setting means sets the third threshold value to a smaller value when the outside air temperature is higher than a predetermined temperature than when the outside air temperature is equal to or lower than the predetermined temperature. Item 4. The vehicle brake control device according to any one of item 3.

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