JP3166425B2 - Self-diagnosis device of anti-skid control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for self-diagnosis of an anti-skid control device of a vehicle for controlling a brake pressure at the time of braking to prevent a locked state of wheels from occurring, and more particularly to an anti-skid control device. The present invention is suitable for self-diagnosis of components, such as an actuator, a motor, and a pump, which are desirably performed when the vehicle starts running.

[0002]

2. Description of the Related Art A conventional anti-skid control device (only A
Although various types have been developed, the basic configuration is to provide an inflow valve, an outflow valve, a pressure pump, etc. between the wheel cylinder and the master cylinder provided on the wheels. By operating this actuator, the fluid pressure acting on the wheel cylinder is increased or decreased, thereby controlling the brake pressure, that is, the braking force. At that time, the wheel speed and the vehicle speed are detected or calculated, the wheel speed or the vehicle speed is determined so that the slip ratio obtained from the both becomes within a predetermined range, and the braking force is applied so as to achieve the wheel speed or the vehicle speed. In many cases, control is performed to prevent wheel locking while obtaining sufficient deceleration.

The inflow valve, outflow valve, pressurizing pump and the like provided in the actuator are controlled by signals from a controller. That is, the inflow valve and the outflow valve act as valves when the solenoid valve is energized or de-energized by a signal from the controller. Further, the pressurizing pump operates as a pump when the drive motor is driven to rotate or non-rotatably by a signal from the controller.

[0004] Since such a vehicle anti-skid control device controls the braking force related to the important performance of the vehicle, it goes without saying that any abnormality is not allowed. Therefore, the self-diagnosis function of this anti-skid control device is provided to diagnose the components and circuits, and when an abnormality is detected, the operation of the anti-skid control device is stopped and the occupant recognizes it by a warning light etc. There has been proposed a self-diagnosis device for performing this. Although what and when to diagnose the anti-skid control device using this self-diagnosis device is not specified in Japan, the solenoid valve of the actuator, the drive motor, and other detectors such as wheel speed sensors are also specified. Diagnosis is generally performed at the time of start, that is, at the start of running (“Study on Automotive ABS”, Sankaido Publishing). The diagnosis of the solenoid valve and the drive motor of the actuator at the time of starting the running of the vehicle is performed for various reasons. That is, unlike other electronic circuits and power supply circuits,
In these actuators, it is necessary to confirm that the operation is normal by forcibly driving the solenoid valve or to confirm that the operation is normal by rotating the drive motor. However, after the power was turned on and before the vehicle started,
When the self-drive diagnosis (self-drive check) of these actuators is performed while the brake pedal is being depressed, the operation noise and pedal vibration generated with the increase and decrease of the hydraulic fluid pressure increase in the S / N ratio. This can be harsh. Further, when the vehicle is stopped on a slope or the like, the brake fluid pressure may be reduced and the vehicle may start moving.

Therefore, when it is detected or calculated that the vehicle has started running, a self-drive check of the actuator is performed. At least at present, it is from 2 to 4 km / h that the controller can confirm the wheel speed, that is, that the vehicle has started running, via the wheel speed sensor. Therefore, the self-actuation of the actuator is actually performed at 5 to 6 km / h. Checks have been made.

However, when the solenoid valve is forcibly driven or the drive motor is forcibly rotated in such a low-speed running state and a state in which the brake pedal is depressed, that is, during braking, the hydraulic fluid pressure is greatly reduced. Changes occur, which may be detected as operating noise or pedal vibration,
There is a risk that they may cause deterioration of the quality of the vehicle.

Therefore, there has been proposed a self-diagnosis apparatus described in, for example, Japanese Patent Application Laid-Open No. 63-46962, in which a self-drive check is performed only when the brake is not operated, that is, when the brake is not applied. In the self-diagnosis device of the anti-skid control device, regardless of the vehicle speed, it is determined that the brake is not operated, for example, by opening and closing a brake lamp switch, that is, when the brake lamp switch is OFF, it is determined that the vehicle is not braking. The self-drive check is performed only during this non-braking operation. In the self-diagnosis device of this anti-skid control device, at least at the time of non-braking when the master cylinder pressure is not increased, the actuator and the drive motor are forcibly driven or rotated, so that the brake fluid pressure does not significantly change. This makes it possible to avoid the noise and vibration problems.

[0008]

However, it is conceivable that the brake pedal is kept depressed at the start of running due to so-called creep, which is seen, for example, in vehicles equipped with an automatic transmission mechanism.
Since it is not determined that the vehicle is in the non-braking state at the time of a so-called ON failure, it is assumed that the self-diagnosis device cannot perform a self-drive check before the vehicle speed reaches, for example, 10 km / h at which normal anti-skid control is performed. Is done.

The present invention has been developed in view of these problems. For example, at a vehicle speed below 10 km / h, a self-drive check can be performed only during non-braking to suppress noise and vibration. And the vehicle speed is 10km / h
It is an object of the present invention to provide a self-diagnosis device for an anti-skid control device that can perform a self-drive check irrespective of braking and non-braking, and can satisfy a request.

[0010]

The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, for example,
Since the vehicle speed of m / h is a vehicle speed region in which the normal anti-skid control is executed, even if the self-drive check is performed at the vehicle speed of 10 km / h, the noise and vibration are not seen from the S / N ratio. Also found that it was not so problematic. Even if the value of 10 km / h is changed, as long as the vehicle speed is such that the noise or vibration of the self-drive check does not matter so much, before the normal anti-skid control is executed, The self-diagnosis must be compulsorily completed in the vehicle speed range, so in the lower vehicle speed range, the self-diagnosis is performed only during non-braking to suppress noise and vibration as much as possible. The above requirements can be satisfied by making the self-diagnosis complete.

The self-diagnosis device of the anti-skid control device of the present invention, as shown in the conceptual diagram of FIG. 1, controls the brake pressure at the time of braking to prevent the locked state of the wheels from occurring. A vehicle speed detecting means for detecting or calculating a vehicle speed in the front-rear direction of the vehicle, and a signal from the vehicle speed detecting means, the vehicle speed having reached a predetermined vehicle speed set in advance after the vehicle starts running. When the vehicle speed reaches the predetermined vehicle speed, a signal from the non-braking self-diagnosis means for performing self-diagnosis of the anti-skid control device only when the vehicle is not braking, and a signal from the vehicle speed detecting means. Unconditional self-diagnosis means for performing self-diagnosis of the anti-skid control device regardless of when braking is not performed.

The predetermined vehicle speed may define the self-diagnosis timing of the anti-skid control device, or may be set in a speed range in which the operation noise and the pedal vibration do not matter even if the self-drive check is performed. May be done.

[0013]

In the self-diagnosis device of the anti-skid control device according to the present invention, as shown in the conceptual diagram of FIG. 1, the vehicle speed detecting means detects the vehicle speed in the front-rear direction, and the signal from the vehicle speed detecting means detects the vehicle speed. When the vehicle speed has not reached a predetermined vehicle speed after the vehicle starts running, that is, for example, 2 to 4 km from which a controller can read a signal from the wheel speed sensor provided as a detector for detecting the wheel speed. / H to, for example, the above 10 km / h, for example, 5 to 6 km / h, the non-braking self-diagnosis means performs self-diagnosis of the actuator and the drive motor by the self-drive check, for example, and the brake lamp switch It is performed only during non-braking, which is determined when it is OFF, and the vehicle speed is set in advance by a signal from the vehicle speed detecting means. Wherein the predetermined vehicle speed, i.e. the 10k was
m / h, the unconditional self-diagnosis means performs a self-diagnosis of the actuator and the drive motor by the self-drive check regardless of the non-braking state or the braking state. Even if the vehicle is equipped with a crane and starts due to creep or when the brake lamp switch is turned on, a predetermined 10 km / h
Then, self-diagnosis of the anti-skid control device is completed by either self-diagnosis means during non-braking or unconditional,
Accordingly, the presence / absence of an abnormality, that is, turning on / off of the warning lamp is performed. Further, the predetermined speed is 10 km /
h or a speed range in which the operation noise and pedal vibrations associated with the self-drive check are not bothersome, and therefore, they do not cause deterioration of the quality of the vehicle.

[0014]

2 to 4 show an embodiment of an anti-skid control device using the self-diagnosis device of the present invention.
Here, it is assumed that the content of the control regarding the prevention of the locking of the wheels of the anti-skid control device for the vehicle is well known.
The self-diagnosis, in particular, the control of the self-drive check, in which the operation is confirmed by substantially driving the actuator or the drive motor or the like, will be described in detail.

First, FIG. 2 briefly shows the overall configuration of the anti-skid control device. Reference numeral 2 denotes a disk brake device mounted on the vehicle, and reference numeral 4 denotes an anti-skid control device for four-wheel independent control of the brake device. The brake device 2 includes a brake pedal 6, a master cylinder 8, a wheel cylinder 10FL of front left to rear right wheels 9FL to 9RR.
10 to 10 RR.

The anti-skid control device 4 includes wheel speed sensors 11FL to 11RR for detecting the rotation state of the wheels.
An ABS warning light 12 for warning an abnormality of the anti-skid control device, a brake lamp switch 13 for lighting a brake lamp, and the wheel speed sensors 11FL to 11FL.
A controller 15 for instructing anti-skid control at the time of braking based on a detection value from 11RR, and a wheel cylinder 10FL-
Actuator 16FL for adjusting each hydraulic pressure of 10RR
~ 16RR.

The wheel speed sensors 11FL to 11RR are constituted by electromagnetic pickups provided at predetermined positions of the wheels 9FL to 9RR, and each output a sine wave AC voltage signal having a frequency proportional to the rotation speed of each wheel. The ABS warning light 12 is provided on, for example, an instrument panel or the like, and is turned on by a lighting signal from the controller 15 when any abnormality is detected in the anti-skid control device. Make the control device recognize that there is an abnormality. The brake lamp switch 13 is, for example, attached to a brake pedal 6, at the time of the brake pedal with turning on the brake lamp, and outputs a braking signal S _B to indicate that a braking.

On the other hand, the actuators 16FL to 16FL
Each of the RRs includes, as shown in FIG. 3, an inflow valve 42 connected between the master cylinder 8 and the wheel cylinder 10FL (〜１０10RR), and a wheel cylinder 10FL (〜１０10R).
R), an accumulator 46 for accumulating pressure and an oil pump 48 for collecting hydraulic oil connected to the output side of the outlet valve 44, and a check valve 50 between the oil pump 48 and the master cylinder 8. And

Of these, the inflow valve 42 and the outflow valve 44
The solenoid valve is a normally-closed solenoid valve whose opening and closing are controlled by hydraulic control signals EV and AV from the controller 15, respectively. In the pressure increasing mode, the control signal EV is turned on, and the control signal A
By turning off V, the inflow valve 42 is opened and the outflow valve 44 is closed, and the operating oil pressure from the master cylinder 8 is applied via the inflow valve 42 to the wheel cylinder 10FL (up to 1).
0RR), so that the wheel cylinder pressure increases. In the pressure reduction mode, the control signal EV is turned off and the control signal AV is turned on, so that the inflow valve 42 is closed,
The outflow valve 44 is opened and the wheel cylinder 10FL
The working oil pressure within (〜１０10 RR) can be recovered to the master cylinder 8 side, and as a result, the wheel cylinder pressure decreases. Further, in the holding mode, by turning off both the control signals EV and AV, the inflow valve 42 and the outflow valve 44 are set to the “closed” state, and the operating oil pressure in the wheel cylinder 10FL (〜１０10RR) can be contained. As a result, the pressure can be maintained. The control signal MR is turned on during the anti-skid control, whereby the oil pump 48 is driven.

The controller 15 has at least A /
Input interface circuit having D conversion function, central processing unit (CPU), storage device (ROM, RAM), D / A
It comprises a microcomputer having an output interface circuit and the like having a conversion function. This controller 1
5, the details of the anti-skid control by the wheel speed sensors 11FL to 11FL are not described here.
This is performed by executing a program stored in the storage device in advance based on the wheel speed detection values W _{FL to} W _{RR from RR} . Specifically calculates a pseudo vehicle speed V _ref from the wheel speed detected value W _FL to _W-RR, for example the difference between the pseudo vehicle speed V _ref and the wheel speed detected value W _FL to _W-RR predetermined slip ratio (1-
The respective wheel speeds falling within the range of β) are calculated, and the hydraulic fluid pressure to each of the wheel cylinders 10FL to 10RR is increased or reduced to control the braking force on each wheel so as to achieve the wheel speed.
As a result, locking of the wheels is reliably prevented while obtaining sufficient deceleration. However, these anti-skid controls do not operate unless an ABS enable signal is transmitted by a self-drive check described later.

On the other hand, since such an anti-skid control device operates a braking force, which is an important traveling performance of the vehicle, there must be no abnormality. For this purpose, self-diagnosis is performed by a self-diagnosis device to detect each abnormality of each member or circuit constituting the anti-skid control device. For example, a self-diagnosis of the microcomputer is performed at the initial diagnosis at the time of power-on, specifically, whether the CPU operates correctly, confirmation of data contents of the ROM and RAM areas and update storage operations thereof, A / D,
Confirmation of the D / A conversion function, confirmation of each communication function, and the like are performed. In addition, the constant diagnosis during running includes power supply voltage monitoring, comparison and confirmation of the calculation results of the microcomputer, runaway monitoring of the microcomputer, and confirmation of the contents of the program. At the time of starting, that is, at the start of traveling, the operation of the actuator is confirmed, specifically, the function diagnosis of the solenoid valves constituting the inflow valve 42 and the outflow valve 44, and the operation of the oil pump 48 and its drive motor are confirmed. this house,
The operation of the actuator at the start of traveling is checked, for example, by forcibly driving the solenoid valves constituting the inflow valve 42 and the outflow valve 44 to confirm the operation control, or by actually rotating the drive motor to rotate the solenoid. And oil pump 48
The so-called self-drive check is performed to confirm that the discharge pressure from is normal. Specifically, the control signals AV, EV, and MR are applied to the actuators 16FL to 16FL.
The output is performed sequentially to 16RR, so that the inflow valve 42, the outflow valve 44, and the oil pump 48 are driven.

The reason why this self-drive check is performed at the start of traveling is as described above. In the present embodiment, the brake lamp switch is OFF during the period from the start of traveling to the vehicle speed of 10 km / h. The self-drive check is performed only at the time of braking, and when the vehicle speed reaches 10 km / h, the self-drive check is compulsorily performed regardless of braking or non-braking. Note that the self-drive check at the time of non-braking is at least currently possible to determine that the vehicle has started running only from the vehicle speed of 2 to 4 km / h at which the microcomputer can read the detection value from the wheel speed sensor. The speed is set at 5 to 6 km / h where the pseudo vehicle speed _Vref is large. The self-diagnosis by the self-drive check is performed collectively for the actuators of each wheel according to the program shown in the flowchart of FIG. 4 and stored in the microcomputer in advance.

This program is started when the power is turned on. First, in step S1, the pseudo vehicle speed _Vref is read. Next, the process proceeds to step S2, where it is determined whether the read pseudo vehicle speed _Vref is 5-6 km / h or more. If the pseudo vehicle speed _Vref is 5-6 km / h or more, the process proceeds to step S3. If not, go to step S
Move to 1.

[0024] In step S3, whether the brake lamp switch 13 is OFF, the words braking signal S _B
Is determined, and if the brake lamp switch 13 is OFF, it is determined that no braking is being performed, and the process proceeds to step S4. If not, the process proceeds to step S5. In step S5, the pseudo vehicle speed V _ref which read is equal to or at 10 km / h or more, when the pseudo vehicle speed V _ref is 10 km / h or more, the process proceeds to step S4, otherwise In this case, the process proceeds to step S1.

In step S4, the control signal A
V, EV, and MR are assigned to each of the actuators 16FL to 16RR.
To check the function of each solenoid valve and the operation of the oil pump and drive motor, and perform a self-drive check. Next, proceeding to step S6, it is determined from the contents of the self-drive check performed in step S4 whether or not all diagnostic contents are normal. If no abnormality is detected in all functions, the process proceeds to step S7. The process proceeds to step S8 otherwise.

In step S7, the actuator 1
Since 6FL to 16RR are normal, it is determined that anti-skid control may be performed, and an ABS operation enable signal is output to terminate the program relating to the self-drive check. On the other hand, in step S8, the actuator 16
Since an abnormality is detected in FL to 16RR, it is determined that the anti-skid control is not to be performed, a lighting signal for turning on the ABS warning light is output, and the program related to the self-drive check ends.

According to the self-diagnosis apparatus, for example, when the vehicle speed reaches 10 km / h when the vehicle equipped with the automatic transmission mechanism starts due to creep, or when the brake lamp switch 13 is turned ON, the vehicle speed is 10 km. /
Since the self-drive check is forcibly performed at h, the self-diagnosis is completed before the normal anti-skid control is performed. Further, since the vehicle speed region of 10 km / h is a region where normal anti-skid control is executed, a self-drive check is performed during braking, and the wheel cylinder pressure and the master cylinder pressure are increased and decreased. Even if the operation noise or the pedal vibration is generated, it is not so much that the occupant is worried, so that the quality of the vehicle does not deteriorate. Before the vehicle reaches 10 km / h, a self-drive check is performed only during non-braking, so that operation noise and pedal vibrations are suppressed to maintain the quality of the vehicle, and to minimize the initial running time. By performing the self-diagnosis at, the reliability of the anti-skid control device is improved.

In this embodiment, the brake lamp switch is turned off for the judgment of non-braking, but
Other criteria may be used. In order to detect the vehicle speed, a pseudo vehicle speed obtained from the wheel speed is used. However, as shown on an instrument panel, the vehicle speed is usually obtained from the rotational speed of the output shaft of the transmission mechanism, or the longitudinal acceleration is obtained. A value obtained by appropriately detecting or calculating by, for example, integrating the acceleration value from the sensor may be used.

Further, in this embodiment, the compulsory self-diagnosis timing of the self-drive check is set to 10 km / h. However, the operation noise at the time of braking by the self-drive check, the pedal vibration, and the like may be used in a vehicle speed range where the driver is not concerned. For example, it is possible to set any vehicle speed. In addition, the self-drive check at the time of non-braking in this embodiment is performed at a vehicle speed of 2 to 4 km / h or more at a vehicle speed of 5 to 6 km / h at which wheel speed can be detected. Before reaching the predetermined speed set in the vehicle speed region where noise and pedal vibration do not matter, if the operation noise of the self-drive check at the time of non-braking is in the vehicle speed region where care is not taken, the self-check at the time of the non-braking will be performed. The driving check may be performed at any time. For example, when the start of traveling of the vehicle is detected by a longitudinal acceleration sensor or the like, specifically, 0 km
/ H can be performed in a vehicle speed range close to / h.

In this embodiment, the self-drive check of the actuators of each wheel is collectively performed. However, if the actuators of each wheel are individually checked,
Operation noise and pedal vibration can be further reduced. Further, in this embodiment, the anti-skid control is not executed unless the ABS operation enable signal is output. However, the fail-safe may be performed when an abnormality is detected while the anti-skid control is being executed. .

[0031]

As described above, according to the self-diagnosis device of the anti-skid control device of the present invention, braking is performed at a predetermined speed set in a vehicle speed region where noise and vibration accompanying self-diagnosis at the time of braking do not matter.・ Because the self-diagnosis is forcibly performed regardless of non-braking, and the self-diagnosis is performed only during non-braking after the vehicle starts running at a speed below this predetermined speed, when starting by creep in vehicles equipped with an automatic transmission mechanism Or even when the brake lamp switch is on,
At the predetermined speed, the self-diagnosis is surely completed, and the deterioration of the quality of the vehicle due to the operation noise and the pedal vibration can be suppressed.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a self-diagnosis device of an anti-skid control device of the present invention.

FIG. 2 is a schematic configuration diagram showing an embodiment of an anti-skid control device including the self-diagnosis device of the present invention.

FIG. 3 is a configuration diagram of an actuator used in the anti-skid control device of FIG. 2 and to be diagnosed by a self-diagnosis device.

FIG. 4 is a flowchart showing a self-diagnosis performed by the self-diagnosis device of FIG. 2;

[Explanation of symbols]

 2 is a brake device 4 is an anti-skid control device 6 is a brake pedal 8 is a master cylinder 9FL-9RR is a wheel 10FL-10RR is a wheel cylinder 11FL-11RR is a wheel speed sensor 12 is an ABS warning light 13 is a brake lamp switch 15 is a controller 16FL 16RR is an actuator 42 is an inflow valve 44 is an outflow valve 48 is an oil pump

Continuation of the front page (56) References JP-A-6-199221 (JP, A) JP-A-50-44379 (JP, A) JP-A-2-303965 (JP, A) JP-A-52-115986 (JP) JP-A-63-71468 (JP, A) JP-A-4-193661 (JP, A) JP-A-63-46962 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) B60T 8/88

Claims (1)

(57) [Claims] 1. A self-diagnosis device for an anti-skid control device for controlling a brake pressure during braking to prevent occurrence of a locked state of a wheel, comprising: vehicle speed detection means for detecting or calculating a vehicle speed in a front-rear direction of the vehicle; Non-braking self-diagnosis means for performing a self-diagnosis of the anti-skid control device only during non-braking, when the vehicle speed does not reach a predetermined vehicle speed set in advance after the vehicle starts running, based on a signal from the vehicle speed detecting means; When the vehicle speed reaches the predetermined vehicle speed set by the signal from the vehicle speed detection means,
A self-diagnosis device for an anti-skid control device, comprising: unconditional self-diagnosis means for performing a self-diagnosis of the anti-skid control device regardless of whether braking or non-braking.