JPH11245802A - Braking force holding device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a braking force holding device that maintains braking assistance even when an unexpected computer reset occurs. SOLUTION: A holding means 8 for holding a brake operation force applied to a brake from a brake pedal, a computer for operating the holding means 8 from a time when the vehicle stops to a moment when the vehicle starts moving, and whether the computer has been normally reset. A non-volatile memory for storing information as to whether an abnormal reset has been performed, and an instantaneous interruption protection means for activating the holding means 8 according to the information stored in the memory when the computer is started up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking force holding device that performs braking assistance under computer control, and more particularly to a braking force holding device that maintains braking assistance even when an unexpected computer reset occurs. .

[0002]

2. Description of the Related Art A brake operation on a slope start is one of the operations requiring skill for a driver. If there is a device that assists braking when starting on a slope, the burden on the driver is reduced. As this kind of device, when a driver depresses a brake pedal, the brake is held until the moment when the vehicle starts even after the brake pedal is released. This can be realized, for example, by providing a holding unit for holding the applied brake operating force in a transmission system between the brake pedal and the brake. The moment when the vehicle stops or the vehicle starts moving is determined by combining various parameters such as various pedals, gear positions, and vehicle speed. Therefore, the computer activates the holding means.

[0003]

However, since the holding means is not operated for a long time, a so-called normally-off type holding means which operates when energized and is deactivated when not energized is used. It is suitable. Such holding means are deactivated when the computer is reset. If the computer is reset due to a power interruption or noise while the holding means is operating, the holding means will also be inactive. Then, for example, when the power supply is momentarily interrupted while the vehicle is stopped on a slope by the holding means, the holding means is deactivated. If the brake pedal is already released at this momentary interruption, the computer does not operate the holding means even if the power is restored, because the combination of the specifications does not indicate the operation of the holding means. In other words, the braking assistance that was operated before the momentary interruption is lost.

It is an object of the present invention to solve the above-mentioned problems and to provide a braking force holding device in which braking assistance is maintained even when an unexpected computer reset occurs.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a holding means for holding a brake operating force applied to a brake from a brake pedal, and a means for starting the vehicle with the holding means when the vehicle stops. A computer that operates until the moment, a non-volatile memory that stores information on whether the computer has been reset normally or abnormally, and operates the holding unit according to the information stored in the memory when the computer starts up. Instantaneous interruption protection means.

The instantaneous interruption protection means stores abnormal reset information in the memory in advance after starting the computer, and stores the normal reset information in the memory only when a power-off command is issued from the key switch to the computer. It may be stored.

[0007]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

As shown in FIG. 1, a braking force holding device according to the present invention includes a stroke sensor 1 for detecting a stroke position from the disengagement of a clutch to a contact, a hydraulic switch 2 for detecting a rise in hydraulic pressure for moving the clutch, A foot brake switch (stop lamp switch) 3 for detecting depression / release of a brake pedal, a neutral switch 4 for detecting whether or not a shift gear position is in a neutral position, a parking brake switch 5 for detecting pulling / release of a parking brake, and opening / closing a door. Door switch 6 to detect,
A speed sensor 7 for detecting a vehicle speed, an electromagnetic valve 8 provided in the middle of a hydraulic system for transmitting a brake pedal operation to a brake, and a controller 9 containing a computer for controlling the electromagnetic valve 8 in accordance with a combination of the above-mentioned specifications. , A braking force holding function off switch 10 for selecting use / non-use of the braking force holding function, a braking force holding function reset switch 11 for stopping the braking force holding function, and a braking force holding function adjusting switch 12 for adjusting the braking force holding function. Consists of

The electromagnetic valve 8 constitutes holding means for holding the brake operation force applied from the brake pedal to the brake. As shown in FIG. 2, the electromagnetic valve 8 is provided in the middle of a hydraulic system 23 that transmits the operation of the brake pedal 21 to the brake 22. This electromagnetic valve 8 operates when energized and operates in one direction (solid line arrow).
This is a so-called one-way valve that allows only oil flow and allows bidirectional (dashed arrow) oil flow if no current is supplied.

A computer built in the controller 9 operates the holding means composed of the electromagnetic valve 8 from the time when the vehicle stops to the moment when the vehicle starts moving. Further, the controller 9 has a non-volatile memory (for example, E ² PROM) for storing information on whether the computer has been reset normally or abnormally. Instantaneous interruption protection means for operating the holding means according to the information stored in the memory when the computer is started,
Consists of computer software.

FIG. 3 shows a power supply system of the vehicle.

As shown in FIG. 3, a key switch 32 (IGN) is provided between a power supply circuit 31 of the controller 9 equipped with the computer and a battery (BATT) of the vehicle.
Position) is inserted. This key switch 32
A contact 34 of the power holding relay 33 is provided in parallel with the power supply. The coil 35 of the power holding relay 33 is driven by a controller. That is, when the driver turns on the key switch 32, the key switch 32
The power is supplied to the controller 9 via the controller 9, and when the computer is started up, the coil 35 of the power supply holding relay 33 is energized. Thereafter, even if the key switch 32 is turned off, the power of the controller 9 is maintained, and the computer detects that the key switch 32 has been turned off, and stops the energization of the coil of the power holding relay 33, whereby the controller 9 is turned off. The power will be cut off.

The normal operation of the braking force holding device according to the present invention will be described.

The start of the holding operation is determined by the logical product of the following specifications.

The transmission gear is in neutral.

The foot brake is depressed.

[0017] The vehicle is stopped.

The parking brake is released.

That is, the neutral switch 4 detects neutral, the foot brake switch 3 detects depression of the brake pedal, the speed sensor 7 detects almost zero vehicle speed, and the parking brake switch 5
Only when has detected the release of the parking brake, it is considered that the starting operation has been started. The logical product does not hold when the vehicle is traveling or the vehicle is parked with the parking brake applied.

The moment when the vehicle starts moving is determined by the logical product of the following specifications.

The clutch is connected more than the half clutch.

The transmission gear position is not neutral.

That is, when the stroke position detected by the stroke sensor 1 is between the half clutch position and the clutch fully engaged position and the neutral switch 4 detects that it is not neutral, it is regarded that the vehicle has started to start.

The braking force holding function off switch 10,
If the logic of the braking force holding function reset switch 11, the braking force holding function adjusting switch 12, the door switch 6, the hydraulic switch 2 and the like is a combination that does not allow the control of the electromagnetic valve 8, the logical product is not satisfied. Regardless, the electromagnetic valve 8 is not controlled. When the start operation is interrupted, for example, when the parking brake is applied or the key switch is returned to the ACC or OFF position, the electromagnetic valve 8 is deactivated.

When the driver depresses the brake pedal to stop the vehicle, the computer turns on the electromagnetic valve 8 after recognizing the complete stop. When the brake pedal 21 is depressed, a brake operation force is applied to the brake 22. However, since the electromagnetic valve 8 is operated, oil flow in a direction to loosen the brake operation force is not allowed, and the brake pedal 21 is depressed. Even after being released, the brake operation force is maintained. Thereafter, when the clutch starts to be engaged, the computer recognizes the moment when the vehicle starts, and deactivates the electromagnetic valve 8. Since the electromagnetic valve 8 is deactivated, the oil flow in the direction to loosen the brake operation force is allowed, and the brake is released because the driver has already released the brake pedal 21. In this way, a smooth start is achieved. The driver can easily switch from the brake pedal to the accelerator pedal, and in the case of starting on a slope, the parking brake operation is not required, so that the burden is reduced.

Next, a description will be given of a malfunction operation when the power supply is momentarily interrupted during starting.

It is assumed that an instantaneous interruption has occurred due to an instantaneous drop in the battery voltage or poor contact of the connection terminals of the power supply system. A momentary interruption resets the computer once. When the power is restored, the computer starts up but does not recognize the vehicle stop because the logical product is not established. Therefore, the electromagnetic valve 8 remains de-energized, and the oil flow in the direction to loosen the brake operation force is allowed. The brake is released. Therefore, when the vehicle starts on a slope, the vehicle may be likely to retreat. Since the driver cannot recognize that the momentary interruption has occurred, the driver has a distrust of the braking force holding function when such a situation occurs.

In the present invention, the following software processing is performed.

As shown in FIG. 4B, when the key switch is turned off, an end flag indicating normal end is set (the end flag indicating abnormal end is erased). This end flag is stored in the nonvolatile memory. After that, the power holding relay 33 is stopped, and the power of the controller 9 is cut off.

As shown in FIG. 4A, when the key switch 32 is turned on (or when the power is restored), the computer first reads the end flag from the non-volatile memory and sets the end flag. Determine whether it indicates normal termination. If abnormal termination, the electromagnetic valve 8 is operated. If the operation ends normally, the electromagnetic valve 8 is not operated. After this processing, the computer sets an end flag indicating an abnormal end (turns off the end flag indicating a normal end). This end flag is stored in the nonvolatile memory. Thereafter, normal operation starts.

As a result, even if the power is turned off at an unexpected timing, an end flag indicating an abnormal end is stored in advance in the nonvolatile memory, so that the end flag is left. Only when the key switch is turned off
An end flag indicating normal end is stored. If the power is momentarily interrupted during the start of the hill, when the power is restored and the computer starts up, the electromagnetic valve 8 is actuated immediately upon the determination of abnormal termination, and the brake operating force applied until immediately before the momentary interruption is maintained. You. Then, at the moment when the vehicle starts, the electromagnetic valve 8 is deactivated and the brake is released, so that a smooth hill start is achieved as in the case where there is no instantaneous interruption.

In the above-described embodiment, the present invention is applied to a manual clutch type vehicle in which a clutch pedal is operated. However, an automatic clutch type in which the clutch is controlled by a computer and an automatic / manual clutch switching mode are provided. Of course, it can also be applied to possible vehicles. In addition, the present invention can be applied to both automatic and manual selection of a transmission gear.

[0033]

The present invention exhibits the following excellent effects.

(1) Even if the power supply is momentarily interrupted while stopping on a slope,
When the power is restored, the brake operation force applied until immediately before the instantaneous interruption is maintained, so that a smooth hill start is achieved in the same manner as when there is no instantaneous interruption.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a braking force holding device according to an embodiment of the present invention.

FIG. 2 is a hydraulic diagram of a brake hydraulic system according to the present invention.

FIG. 3 is a power supply system diagram of a vehicle according to the present invention.

FIG. 4 is a flow chart of a process executed by the instantaneous interruption protection means of the present invention, wherein (a) shows a computer startup process and (b) a computer termination process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stroke sensor 3 Foot brake switch 5 Parking brake switch 7 Speed sensor 8 Solenoid valve 32 Key switch

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Junichi Imai 8 Tsuzura, Fujisawa-shi, Kanagawa Prefecture Isuzu Motors Fujisawa Plant (72) Inventor Kazuhiko Kobayashi 4-1-1 Uedanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Inside Transtron Co., Ltd. (72) Inventor Hiroyuki Arai 4-1-1, Kamikodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Transtron Co., Ltd.

Claims (2)

[Claims] 1. A holding means for holding a brake operating force applied to a brake from a brake pedal, a computer for operating the holding means from a time when the vehicle is stopped to a moment when the vehicle starts moving, and a state where the computer is reset normally or abnormally. A non-volatile memory for storing information on whether the memory has been reset, and an instantaneous interruption protection means for activating the holding means in accordance with the information stored in the memory when the computer is started up. Power holding device. 2. The instantaneous interruption protection means stores abnormal reset information in the memory in advance after starting the computer, and stores the normal reset information only when a power-off command is issued to the computer from a key switch. 2. The braking force holding device according to claim 1, wherein the braking force is stored in a memory.