JPH08104216A - Brake control device for automobile - Google Patents

Abstract

PURPOSE: To obtain an accurate initial value at ignition-on time, even without providing an exclusive temperature sensor, relating to a temperature of an arbitrary brake system element. CONSTITUTION: At off time of an ignition switch 70, a sensor value of a water temperature sensor 61, brake oil temperature and a solenoid temperature during measuring in a brake actuator 40 are stored in a data memory 51. On the other hand, at on time of this switch 70, based on a cooling coefficient of an engine water temperature determined by a sensor value stored in the data memory 51 of the water temperature sensor 61, present sensor value of this sensor 61 and a present sensor value of an outside air temperature sensor 62, a lapse of time from off to on of this switch 70 is calculated. Based on the cooling coefficient of a brake oil temperature and solenoid temperature determined by the calculated lapse of time, brake oil temperature stored in the data memory 51, solenoid temperature and a present sensor value of the outside air temperature sensor 62, a present temperature of these brake oil temperature and solenoid temperature are estimated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake control device for an automobile, and more particularly, to force execution of the brake control when the temperature of a brake system element, which temperature rises with the execution of the brake control, exceeds a predetermined temperature. Such as canceling
The present invention relates to improvement of a device that changes the control content.

[0002]

As is well known, when a brake system of an automobile is overheated, a so-called vapor lock phenomenon occurs in which brake fluid (oil) vapor accumulates in brake pipes, wheel cylinders, etc. and the brake does not work. Performance deteriorates.

Therefore, conventionally, when the temperature of a brake system element, which temperature rises with the execution of brake control such as traction control, exceeds a predetermined temperature, the execution of the brake control is forcibly released to prevent such vapor lock phenomenon. We try to prevent the occurrence.

As an example thereof, Japanese Patent Laid-Open No. 58-16 is available.
In the device described in Japanese Patent Publication No. 948, a dedicated temperature sensor is provided in the brake disc, and when a temperature of the brake disc detected through the temperature sensor exceeds a predetermined temperature, an alarm lamp is turned on or brake control is executed. Emergency measures such as forced cancellation are taken.

[0005]

When the temperature of the brake system element such as the above-mentioned brake disc can be directly detected through the temperature sensor, the temperature of the brake system element can be always accurately grasped. It is certainly possible to release the brake control in a stable manner.

However, the use of such a dedicated temperature sensor itself causes an increase in cost and makes the brake control device expensive. In addition, since the number of brake system elements in which the temperature sensor can be arranged is naturally limited, the temperature of an element desirable for performing the above-mentioned brake control, including release, is not always monitored.
In the brake system, the temperatures of the elements such as the solenoid and the brake fluid that form the brake actuator are more important, and it is more desirable that the temperatures of these elements can be monitored.

The present invention has been made in view of such circumstances, and it is possible to always accurately grasp the temperature of an arbitrary brake system element without using a temperature sensor, regardless of the state of the vehicle. An object is to provide a brake control device for an automobile.

[0008]

In order to achieve such an object, according to the invention as set forth in claim 1, when the temperature of a brake system element which rises in temperature with execution of the brake control exceeds a predetermined temperature, the brake control is performed. As a brake control device of a vehicle for changing the control content of the vehicle, an initial temperature estimating means for estimating an initial temperature of the brake system element associated with ignition on based on a temporal transition of an arbitrary state quantity of the vehicle is provided. .

Further, in the invention according to claim 2, in the structure according to claim 1, the initial temperature estimation means is a storage means for storing a state quantity measurement value of the vehicle at the time of ignition off, and the state. The measured value stored in the storage means of the quantity and the value measured at the time of ignition-on of the same state quantity, and calculating means for calculating an initial temperature of the brake system element accompanying the ignition-on. Configure.

Further, in the invention according to claim 3, in the structure according to claim 2, the initial stage is focused on that the vehicle is usually provided with a fluid temperature sensor used for engine control or the like. Temperature estimation means, storage means for storing the sensor value of the fluid temperature sensor and the brake system element temperature at the time of ignition off,
Compute the elapsed time from the previous ignition off to the current ignition on based on the sensor value stored in the storage means of the fluid temperature sensor and the sensor value of the fluid temperature sensor at the time of ignition on 1 calculating means, and 2nd calculating means for calculating an initial temperature of the brake system element when the ignition is turned on, based on the calculated elapsed time and the brake system element temperature stored in the storage means. Compose with.

According to the invention of claim 4, in the configuration of claim 2, the vehicle is also
Paying attention to the fact that at least two first and second fluid temperature sensors used for engine control and the like are already installed, the initial temperature estimation means is set to a sensor value of the first fluid temperature sensor when the ignition is off. And a storage means for storing the temperature of the brake system element, a sensor value stored in the storage means of the first fluid temperature sensor, a sensor value of the first fluid temperature sensor when the ignition is on, and A first calculation for calculating the elapsed time from the previous ignition OFF to the current ignition ON based on the cooling coefficient of the first fluid temperature determined by the sensor value when the second fluid temperature sensor is ON. Means and the calculated elapsed time,
Based on the brake system element temperature stored in the storage means and the cooling coefficient of the brake system element temperature determined by the sensor value at the time of ignition on of the second fluid temperature sensor, the ignition on of the brake system element is performed. And a second calculation means for calculating the initial temperature at the time.

In the invention according to claim 5, in the structure according to any one of claims 1 to 4, the brake system element whose initial temperature is estimated is one of a solenoid and a brake oil which constitute a brake actuator. Both.

[0013]

When trying to measure the temperature of an arbitrary brake system element without using a dedicated temperature sensor, the problem is how to set the initial value when the ignition of the vehicle is turned on.

For example, when the initial value is set to "0" (reset), the state when the ignition is turned off last time is canceled and before the temperature of the brake system element to be measured reaches a predetermined temperature, the above-mentioned value is set. There is a possibility of falling into vapor lock. In this case, if the time from when the ignition was turned off last time until the time when the ignition is turned on this time is long enough, it does not matter so much, but if the time is short, such as when restarting due to an engine stall, etc. There is a large gap between the actual temperature of the element and the measured temperature, which tends to cause these inconveniences.

On the other hand, it may be considered that the temperature of the brake system element at the time of ignition off is stored in a non-volatile memory and this stored temperature is set as an initial value at the time of ignition on. However, in that case, conversely, if the time from the previous ignition off to the ignition on this time is short, it does not matter so much, but when the time is sufficiently long, the actual temperature of the brake system element still remains. There is a large gap between the measured temperature and the temperature. Then, in this case, there is a disadvantage that the brake control is unnecessarily quickly released, although the actual temperature of the brake system element is not so high.

Therefore, as in the invention according to claim 1, the initial temperature estimating means for estimating the initial temperature of the brake system element accompanying the ignition on based on the time transition of the arbitrary state quantity of the vehicle is provided. Get By doing so, it becomes possible to accurately set the initial value when the ignition is turned on through the estimation means.

That is, as the state quantity of the automobile, the temperature of engine cooling water, torque converter oil, various lubricating liquids, etc. changes with time in a predetermined correlation with the actual temperature of the brake system element. Therefore, if the temperature changes of those state variables are monitored and the temperature of the brake system element associated with the ignition is turned on, an accurate initial value for that temperature of the vehicle can be obtained. Will be able to get.

Incidentally, when the accurate initial value is determined at the time of turning on the ignition, the subsequent temperature of the brake system element can be accurately measured based on the execution time of the brake control and the like.

Further, in this case, the brake system element which is the object of temperature measurement is arbitrary, and the element desired as the object of measurement can be freely selected. Further, according to the invention described in claim 2, the initial temperature estimating means is (A) a storage means for storing a state quantity measurement value of the vehicle when the ignition is off. (B) Computation for comparing the measured value of the state quantity stored in the storage means with the value of the same state quantity measured at the time of ignition-on to calculate the initial temperature of the brake system element accompanying the ignition-on. means. With such a configuration, it becomes possible to estimate the initial temperature of the brake system element by accurately grasping the temporal transition thereof based on the comparison of the state quantities of the vehicle.

By the way, such an automobile is usually equipped with a fluid temperature sensor such as a cooling water temperature sensor used for engine control, and the state quantity and the like can be monitored by the sensor value of the sensor. You can do it.

Therefore, as in the invention according to claim 3, as the initial temperature estimating means, specifically, (a) the sensor value of the fluid temperature sensor and the brake system element temperature at the time of ignition off are stored. Means of storage. (B) Based on the sensor value stored in the storage means of the fluid temperature sensor and the sensor value of the fluid temperature sensor when the ignition is turned on, the elapsed time from the previous ignition off to the current ignition on is shown. First computing means for computing. (C) Second calculating means for calculating an initial temperature of the brake system element when the ignition is turned on, based on the calculated elapsed time and the brake system element temperature stored in the storage means. Can be configured to include each.

With this configuration, the elapsed time from the ignition off to the ignition on, that is, the cooling time can be easily obtained by the first computing means, and the temperature (initial temperature) of the brake system element after the cooling time can be calculated. This can also be easily obtained through the second calculating means.

Further, it is generally considered that the cooling water temperature and the temperature of the brake system element are naturally cooled and finally converged to the outside air temperature. An outside air temperature sensor that measures the outside air temperature is also usually installed in the vehicle in advance.

Therefore, for example, a temperature sensor for measuring the fluid temperature having a strong correlation with the temperature of the brake system element, such as the cooling water temperature sensor, is used as the first fluid temperature sensor, and the outside temperature sensor is used as an objective comparison standard. The temperature sensor for measuring the fluid temperature is defined as the second fluid temperature sensor, and the initial temperature estimating means further comprises: (a ') the first temperature when the ignition is off. Storage means for storing the sensor value of the fluid temperature sensor and the brake system element temperature. (B ') The sensor value stored in the storage means of the first fluid temperature sensor, the sensor value of the first fluid temperature sensor when the ignition is on, and the ignition value of the second fluid temperature sensor A first calculation means for calculating the elapsed time from the previous ignition off to the current ignition on, based on the cooling coefficient of the first fluid temperature determined by the sensor value in. (C ') The calculated elapsed time, the brake system element temperature stored in the storage means, and the second
Second computing means for computing an initial temperature of the brake system element when the ignition is turned on, based on a cooling coefficient of the brake system element temperature which is determined by a sensor value of the fluid temperature sensor when the ignition is turned on. In addition, it is possible to perform a more accurate calculation of the cooling time (elapsed time from ignition off to ignition on) and the temperature of the brake system element (initial temperature) after this cooling time. become able to.

On the other hand, in these configurations, the brake system element which is the object of temperature measurement is arbitrary, and the desired element can be freely selected, as described above. According to the invention of claim 1, the brake system element that is the object of this temperature measurement is one or both of the solenoid and the brake fluid that constitute the brake actuator. Then, it becomes possible to directly estimate and measure the temperature of the most important factor in determining the state of the brake system. In order to estimate and measure the temperatures of these elements, it is sufficient to obtain the cooling characteristics for each of these elements, the temperature rise characteristics associated with the execution of brake control, and the like through experiments in advance.

[0026]

1 and 2 show an embodiment of a vehicle brake control device according to the present invention.

The device of this embodiment is a device for forcibly canceling the execution of the brake control when the brake oil temperature and the solenoid temperature, which increase in temperature with the execution of the brake control, exceed a predetermined temperature. It is configured as a device capable of suitably estimating the initial values of the oil temperature and the solenoid temperature when the ignition is turned on.

First, the configuration of the apparatus of this embodiment will be described with reference to FIGS. 1 and 2. In FIG. 1, reference numerals 11L and 11R are wheel speed sensors arranged corresponding to the left and right driving wheels 10L and 10R, respectively, and reference numerals 21L and 21R are respectively left and right rolling wheels 2.
It is a wheel speed sensor arranged corresponding to 0L and 20R.

These wheel speed sensors 11L and 11R,
Each of 21L and 21R is configured by a known electromagnetic pickup sensor including a signal rotor that rotates in synchronization with the corresponding wheel, and a pickup coil that is fixedly arranged facing the rotor. The outputs of the wheel speed sensors 11L and 11R, 21L and 21R are all taken into the electronic control unit 50 described later.

Further, in FIG. 1, reference numerals 12L and 1
2R is a wheel cylinder arranged corresponding to the left and right driving wheels 10L and 10R, respectively, and 22L and 22R are wheel cylinders arranged corresponding to the left and right rolling wheels 20L and 20R, respectively. .

These wheel cylinders 12L and 12
R, 22L, and 22R are also well-known members that are hydraulically driven according to the depression of the brake pedal 31 that constitutes the brake mechanism 30 to apply a braking force to the corresponding wheels.

The brake actuator 40 is arranged corresponding to the drive wheels 10L and 10R which are differentially connected via the differential 13, based on the hydraulic pressure supplied through the accumulator and pump 41. This is also a well-known member for individually driving the wheel cylinders 12L and 12R.

The brake actuator 40 has a hydraulic circuit that is hydraulically controlled by the electronic control unit 50, and detects a slip of a predetermined amount or more of the drive wheels 10L and 10R. When the traction control is executed, the brake hydraulic pressure corresponding to the duty and cycle of the control pulse CP output from the electronic control unit 50 is applied to the wheel cylinders 12L, 12 described above.
Supply to R. As a result, drive wheels 10L, 10R
In that case, even if the brake mechanism 30 is not operated,
The braking force corresponding to the duty and cycle of the control pulse CP is applied.

FIG. 2 shows an example of such a brake actuator 40. In the brake actuator 40, the hydraulic pressure used for the brake control (traction control) is stored in the accumulator 41a.

The pressure of the accumulator 41a is kept constant under the supervision of the pressure sensor 42.
That is, the electronic control unit 50 operates the pump 41b to restore the pressure of the accumulator 41a when the pressure detected by the pressure sensor 42 falls below the set value.

On the other hand, brake control (traction control)
Is executed, the hydraulic pressure switching solenoid valves 43, 44,
And 45 are turned on by the electronic control unit 50.
When the solenoid valve 43 is turned on in this manner, it shuts off the pressure between the wheel cylinders 12L and 12R and the master cylinder 32.

When the solenoid valve 44 is also turned on, the pressure from the accumulator 41a is guided to the wheel cylinders 12L and 12R. And solenoid valve 45
Is also turned on so that the hydraulic pressure (brake oil) that is no longer needed in the brake control is discharged to the reservoir 33.

Through these actions of the solenoid valves 43, 44, and 45, the pressure of the accumulator 41a is applied to the wheel cylinders 12L and 12R, and the rotation of the drive wheels 10L and 10R engaged with the pressure is suppressed.

In this state, the electronic control unit 50 controls the hydraulic pressure control solenoid valves 46 and 47 to the pressure increasing mode, the holding mode or the pressure reducing mode to control the hydraulic pressure applied to the wheel cylinders 12L and 12R.

By the way, as described above, when the brake system is overheated due to the execution of the brake control, a so-called vapor lock phenomenon is caused and the braking performance is deteriorated.

Therefore, the brake actuator 4
At 0, it is necessary to directly monitor the brake oil temperature and forcibly terminate the execution of the brake control when the oil temperature exceeds a predetermined temperature in order to prevent such vapor lock phenomenon from occurring. Is desirable.

Further, such overheating of the brake system is also caused by the solenoids constituting the solenoid valves 43 to 47. That is, when the energization of the exciting coil is continued for a long time when the solenoid is driven, heat generated by Joule heat is naturally accumulated, and in the worst case, the exciting coil may be disconnected. It can cause. In this way, when the exciting coil is disconnected, it is of course impossible to control those solenoid valves thereafter.

Therefore, the brake actuator 40
In this case, it is possible to directly monitor the temperature of the solenoids constituting the solenoid valves 43 to 47 and to forcibly terminate the execution of the brake control even when the temperature of the solenoids exceeds a predetermined temperature. It is desirable to prevent disconnection of the exciting coil.

Therefore, in the apparatus of this embodiment, the brake fluid temperature and the solenoid temperature are directly monitored. Moreover, in the device of the embodiment, a dedicated temperature sensor is not used to measure the brake fluid temperature and the solenoid temperature, and when setting the initial values at the time of ignition ON of those temperatures, The sensor value of the temperature sensor used for engine control, air conditioning control, etc. is used.

That is, as also shown in FIG. 1, in the apparatus of the embodiment, the sensor value of the water temperature sensor 61 for detecting the cooling water temperature of the engine 60 and the sensor value of the outside air temperature sensor 62 for detecting the outside air temperature are electronically measured. It is also taken into the control device 50, and through the electronic control device 50, (1) the sensor value of the water temperature sensor 61 when the IG (ignition) switch 70 is turned off, and the measured values of the brake fluid temperature and the solenoid temperature. Backup RAM
Etc. are stored in the data memory 51, which is assumed to be a non-volatile memory such as. (2) When the IG switch 70 is turned on, the braking at the simultaneous points is performed based on the temperature values stored in the data memory 51 and the sensor values of the water temperature sensor 61 and the outside air temperature sensor 62 at that time. Estimate oil temperature and solenoid temperature. In this manner, the initial value setting for the brake fluid temperature and the solenoid temperature is executed.

3 and 4 respectively show an electronic control unit 5
Fig. 3 shows an initial value estimation procedure and an estimation mode for the brake fluid temperature and the solenoid temperature according to 0,
Hereinafter, with reference to FIGS. 3 and 4, the method of estimating the initial values by the apparatus of the embodiment will be described in detail.

The procedure or the mode of estimating the initial value shown in FIGS. 3 and 4 is different, and the brake oil temperature and the solenoid temperature are common.
Therefore, in FIG. 3 and FIG. 4, for convenience, both the brake fluid and the solenoid are shown as “monitoring targets” by using a common expression. Further, in the following description, the term “monitoring target” refers to both the brake fluid and the solenoid.

If the IG switch 70 is turned on, the electronic control unit 50 determines so-called ignition on (step 100) and sequentially executes the processes listed below.

(1) First, the engine water temperature A and the monitoring target temperature D stored in the data memory 51 are read (step 101). Both of these temperatures A and D are
Immediately before the IG switch 70 is turned off, it is measured by the water temperature sensor 61 and the electronic control unit 50 is used.
Is the temperature calculated (measured) through. In addition, these temperatures correspond to the temperature A shown in FIG. 4B and the temperature D shown in FIG. 4C, respectively.

(2) Next, the sensor value B of the water temperature sensor 61 and the sensor value TT of the outside air temperature sensor 62 at that time are input (step 102). The sensor value B of the water temperature sensor 61 corresponds to the temperature B shown in FIG. 4B and 4C show the cooling characteristics of the engine water temperature and the monitored temperature when the outside air temperature TT is constant (const), respectively. The gradient changes depending on. That is, the sensor value TT of the outside air temperature sensor 62
The gradient is specified by each of them, and the value of C or C ′ which becomes the cooling coefficient is specified. In the apparatus of the embodiment, the cooling characteristics illustrated in FIGS. 4B and 4C are registered in advance in the electronic control unit 50 as a map for each outside air temperature TT.

(3) Thus, the electronic control unit 50 which reads the engine water temperature A and the temperature D to be monitored at the time of the previous ignition off, and inputs the engine water temperature B and the outside air temperature TT at this time of the ignition on.
Calculates the elapsed time ΔT from the ignition off to the ignition on as ΔT = f (A, B, C) based on the engine water temperature map (step 103). In the same equation, the value C is the above-mentioned cooling coefficient of the engine water temperature map determined by the outside air temperature TT. Also, the elapsed time ΔT calculated in this way
Is the time corresponding to the off time ΔT of the IG switch 70 additionally shown in FIG.

(4) The electronic control unit 50 which has calculated the elapsed time ΔT then sets the initial value E of the temperature to be monitored as E = f (ΔT, D, C ′) based on the elapsed time ΔT, and It is calculated based on the monitored temperature map (step 104). Also in the same equation, the value C ′ is the above-mentioned cooling coefficient of the monitoring target temperature map determined by the outside air temperature TT. The initial value E thus calculated is the initial value when the ignition is turned on with respect to the brake fluid temperature and the solenoid temperature estimated in the apparatus of the embodiment, and is a temperature corresponding to the temperature E shown in FIG. 4C. Become. Of course, in reality, the values of the brake fluid temperature and the solenoid temperature are different.

(5) The electronic control unit 50, which has thus obtained the initial value E for the temperature to be monitored, sets this in an appropriate memory, and the wheel speed sensors 11L and 11R,
Well-known normal brake control based on the outputs of 21L and 21R is started (step 105).

(6) As a part of the brake control, the electronic control unit 50 then determines the temperature F of the monitoring target each time based on the execution time of the braking control with respect to the set initial value E of the monitoring target temperature. It is calculated (step 106), and it is monitored whether the calculated temperature F exceeds a predetermined temperature set in advance for these monitoring targets (step 107).

(7) In this monitoring, when it is judged that the temperature F to be monitored has not reached the above-mentioned predetermined temperature,
That is, when it is determined that both the brake fluid temperature and the solenoid temperature are in safe temperature ranges, the data memory registration engine water temperature A ← engine water temperature sensor value B data memory registration monitoring target temperature D ← monitoring target temperature measurement (calculation) ) As the value F 1, the registered contents in the data memory 51 are updated (step 108). It should be noted that such processing in steps 105 to 108 is repeatedly executed at a cycle of, for example, 5 to 6 ms (milliseconds) until the IG switch 70 is turned off, that is, until the electronic control unit 50 determines that the ignition is off. (Step 109).
Further, since the registered contents in the data memory 51 are updated in this manner, the engine water temperature sensor value B and the monitored temperature measurement (calculation) value F are set when the ignition is off.
The latest values of the above-mentioned values at that time are stored in the data memory 51 as the temperatures A and D, respectively.

(8) On the other hand, in the monitoring in step 107, when it is determined that the temperature F to be monitored exceeds the predetermined temperature, that is, either the brake fluid temperature or the solenoid temperature is dangerous. If it is determined that the temperature has risen to the temperature, the braking control in progress is forcibly terminated (step 110). As described above, the safety of the brake system described above is maintained through the processing by the electronic control unit 50.
Although detailed illustration is omitted in FIG. 3 for the sake of convenience, if the brake control is forcibly terminated before the ignition is turned off, the temperature of the monitoring target that has exceeded at least the predetermined temperature is then exceeded. Until is low enough
The "normal brake control" shown as step 105 is maintained in a so-called wait state.

As described above, in the brake control apparatus of this embodiment, the initial values of the brake fluid temperature and the solenoid temperature when the ignition is turned on are estimated as the temperatures correlated with the temporal transition of the engine water temperature. Therefore, for the brake oil temperature and the solenoid temperature, it is possible to set accurate initial values according to the respective conditions of the vehicle without using a dedicated temperature sensor for them.

Therefore, even when the brake control is executed thereafter, the brake fluid temperature and the solenoid temperature can always be accurately grasped, and the timing for forcibly canceling the execution of the brake control is also improved. It will also be possible to always set properly.

In the apparatus of the embodiment, the engine water temperature, the brake fluid temperature, and the solenoid temperature change with time, that is, their cooling characteristics (cooling coefficient) after the ignition is turned off are related to the outside air temperature. Since the corrected time is used to obtain the elapsed time ΔT and the initial value E, the accuracy of the obtained values is naturally high and is closer to the actual value.

However, with respect to these cooling characteristics, it is possible to estimate a realistic initial temperature for realizing the above-mentioned brake control and forced release thereof, without necessarily making correction by the outside air temperature. In that case, the initial value estimating function according to the device of the above embodiment can be realized by a simpler and smaller-scale algorithm. In this case, the elapsed time ΔT is map-calculated as ΔT = f (A, B), and the initial value E is map-calculated as E = f (ΔT, D).

In the apparatus of this embodiment, the brake fluid and the solenoid are taken as the brake system elements whose temperature is to be monitored, but the selection is arbitrary. As described above, the temperatures of these brake fluids and solenoids are important factors in determining the state of the brake system, but the brake system elements to be monitored in the present invention are not limited to these elements. .
In order to estimate and measure the temperature of the selected brake system element, the cooling characteristics of each element and the temperature rise characteristics associated with the execution of brake control, etc. must be obtained through preliminary experiments. As mentioned above, it is sufficient.

Further, in the apparatus of the embodiment, the temperature of the engine cooling water (engine water temperature) is adopted as the state quantity of the vehicle which correlates with the cooling characteristic of the brake system element, but the selection of these state quantities is also arbitrary. is there. Besides, for example, the temperature of the torque converter oil, the temperature of various lubricating liquids, and the like can be appropriately adopted. And even in that case, the initial temperature of the brake system element is estimated in a manner according to the above-described embodiment.

In the apparatus of the embodiment, when the temperature F to be monitored exceeds the predetermined value, the execution of the brake control is forcibly released, but it may be sufficient to appropriately change the control content of the brake control. It is not always necessary to cancel the execution (for example, shifting to intermittent control).

[0064]

As described above, according to the present invention, the temperature of an arbitrary brake system element can be adjusted according to the respective conditions of the vehicle when the ignition is turned on, without using a dedicated temperature sensor. You will be able to get the exact initial value of.

Therefore, the temperature of the brake system element can always be accurately grasped, and by extension, the timing at which the execution of the brake control is forcibly released can always be properly set.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a vehicle brake control device of the present invention.

FIG. 2 is a hydraulic circuit diagram showing an example of a brake actuator configuration.

FIG. 3 is a flowchart mainly showing an initial temperature estimation procedure of the apparatus of the embodiment.

FIG. 4 is a time chart showing an aspect of estimating an initial temperature of the apparatus of the embodiment.

[Explanation of symbols]

10 (10L, 10R) ... drive wheel, 11 (11L, 11
R) ... Wheel speed sensor (driving wheel speed sensor), 12 (1
2L, 12R) ... Drive wheel wheel cylinder, 13 ... Differential, 20 (20L, 20R) ... Rolling wheel, 21
(21L, 21R) ... Wheel speed sensor (rolling wheel speed sensor), 22 (22L, 22R) ... Rolling wheel wheel cylinder, 30 ... Brake mechanism, 31 ... Brake pedal, 32
... master cylinder, 33 ... reservoir, 40 ... brake actuator, 41 ... accumulator and pump, 42
... pressure sensor, 43-47 ... solenoid valve (solenoid), 5
0 ... Electronic control device, 51 ... Data memory, 60 ... Engine, 61 ... Water temperature sensor, 62 ... Outside air temperature sensor, 70 ... I
G switch.

Claims (5)

[Claims] Claim: What is claimed is: 1. A brake control device for a vehicle, wherein when the temperature of a brake system element, the temperature of which increases with execution of the brake control, exceeds a predetermined temperature, the brake control device for the vehicle changes the control content of the brake control. A brake control device for an automobile, comprising: an initial temperature estimating means for estimating an initial temperature of the brake system element when the ignition is turned on, based on the temporal transition of. 2. The initial temperature estimating means stores a state quantity measurement value of the vehicle at the time of ignition off, and a state quantity of the state quantity measurement value stored in the storage means. The brake control device for an automobile according to claim 1, further comprising: a calculation unit that compares a value measured when the ignition is turned on to calculate an initial temperature of the brake system element when the ignition is turned on. 3. The vehicle is already provided with a fluid temperature sensor for detecting an arbitrary fluid temperature, and the initial temperature estimation means is configured to detect a sensor value of the fluid temperature sensor and a temperature of the brake system element at the time of ignition off. Based on the storage means to be stored, the sensor value stored in the storage means of the fluid temperature sensor, and the sensor value of the fluid temperature sensor at the time of ignition on, from the previous ignition off to the current ignition on A first calculating means for calculating the elapsed time of the brake system element, and an initial temperature of the brake system element when the ignition is turned on, based on the calculated elapsed time and the brake system element temperature stored in the storage means. 3. The vehicle brake system according to claim 2, further comprising: The control device. 4. The vehicle is already provided with a first fluid temperature sensor for detecting an arbitrary first fluid temperature and a second fluid temperature sensor for detecting an arbitrary second fluid temperature. The initial temperature estimation means is a storage means for storing a sensor value of the first fluid temperature sensor and the brake system element temperature at the time of ignition off, and a storage means for the first fluid temperature sensor. Based on the cooling value of the first fluid temperature determined by the sensor value of the first fluid temperature sensor when the ignition is on, and the sensor value of the second fluid temperature sensor when the ignition is on, A first calculation means for calculating an elapsed time from when the ignition was turned off last time to when the ignition is turned on this time; the calculated elapsed time; Based on the braking system element temperature stored in the means and the cooling coefficient of the brake system element temperature determined by the sensor value of the second fluid temperature sensor when the ignition is turned on. The brake control device for an automobile according to claim 2, further comprising: a second calculation unit that calculates an initial temperature. 5. The brake control device for a vehicle according to claim 1, wherein the brake system element for which the initial temperature is estimated is one or both of a solenoid and a brake oil that form a brake actuator.